|
- <html>
- <head>
- <title>Calcium and Disease: Hypertension, organ calcification, & shock, vs. respiratory energy</title>
- </head>
- <body>
- <h1>
- Calcium and Disease: Hypertension, organ calcification, & shock, vs. respiratory energy
- </h1>
-
- <p>
- <em>
- SOME CONTEXTS In biology and biochemistry, calcium is the substance most often studied, so it is
- significant that researchers still speak of a calcium paradox. There are several such paradoxes: As
- bones lose calcium, the soft tissues calcify; when less calcium is eaten, blood calcium may increase,
- along with calcium in many organs and tissues; if an organ such as the heart is deprived of calcium for
- a short time, its cells lose their ability to respond normally to calcium, and instead they take up a
- large, toxic amount of calcium. Magnesium deficiency and calcium deficiency have some similar symptoms
- (such as cramping), but magnesium is antagonistic to calcium in many systems. It is the basic protective
- calcium blocker. Inflammation leads to excessive uptake of calcium by cells, and is a factor in obesity,
- depression, and the degenerative diseases. Protein deficiency is an important cause of deranged calcium
- metabolism. Vitamins K, E, and A are important in regulating calcium metabolism, and preventing
- osteoporosis. Aspirin (with antiestrogenic and vitamin E-like actions) is protective against bone
- resorption and hypercalcemia.
- </em>
- <hr />
- It is extremely important to realize that calcium deposits in soft tissues become worse when the diet is <em
- >low in calcium.</em> Persons suffering from arthritis, bursitis, scleroderma, hardening of the arteries and
- any abnormality where calcium deposits or spurs may cause pain are often afraid to eat foods rich in
- calcium. Actually they can never improve until their calcium and magnesium intakes are adequate. Not
- infrequently physicians tell individuals with kidney stones to avoid all milk, thereby causing stones to
- form even more rapidly. Such calcium deposits can also occur when vitamin E is undersupplied. After
- open-heart surgery, when both magnesium and vitamin E are drastically needed and could easily be given, the
- calcification of heart muscles often becomes so severe that it can cause death within a few days. Pages
- 171-172,<em>
- Lets Eat Right to Keep Fit,</em> Adelle Davis, Signet, 1970.
-
- <hr />
-
- Almost all biologists think of the organism as a machine, regulated by information according to innate
- programs. When it comes down to the details, their explanations sometimes make Rube Goldbergs imaginary
- contraptions seem elegant. At their best, they usually rely on some mysterious things called ionic pumps,
- that perform active transport, powered by little motors, under instructions from molecules that act on their
- specific receptors. When things get unmanageable, the biologists speak of paradoxes. Calcium is the most
- studied of all regulatory molecules, so it isnt surprising that there is more than one calcium paradox. But
- there are ways of looking at the organism, focusing on energy metabolism, that dont involve the <em>ad
- hoc</em> theory of calcium pumps, and that make it easy to keep things in context. Ionized atoms and
- molecules behave in orderly ways, in relation to their size and their electrical charge. Organic material,
- even when its dead, selectively binds certain metal ions, and excludes others. The living organism produces
- a stream of metabolic products, such as carbon dioxide or lactic acid, which interact specifically with each
- other and with the metal ions, modifying their concentrations inside cells and in the body fluids. This
- movement of ions can be called active transport, without invoking the mysterious machinery of membrane
- pumps. Chemical changes produced inside cells, for example by respiration, create different electrical
- charges in different compartments (inside and outside of capillaries, for example) which affect the
- movements of water and ions, by simple physical processes, not by molecular pumps. The result of these
- passive and active processes is that each kind of ion has a characteristic concentration in each
- compartment, according to the metabolic energy state of the organism. Magnesium and potassium are mainly
- intracellular ions, sodium and calcium are mainly extracellular ions. When cells are excited, stressed, or
- de-energized, they lose magnesium and potassium, and take up sodium and calcium. The mitochondria can bind a
- certain amount of calcium during stress, but accumulating calcium can reach a point at which it inactivates
- the mitochondria, forcing cells to increase their inefficient glycolytic energy production, producing an
- excess of lactic acid. Abnormal calcification begins in the mitochondria. When cells are stressed or dying,
- they take up calcium, which tends to excite the cells at the same time that it inhibits their energy
- production, intensifying their stress. A cramp or a seizure is an example of uncontrolled cellular
- excitation. Prolonged excitation and stress contribute to tissue inflammation and fibrosis. Gross
- calcification generally follows the fibrosis that is produced by inflammation. Arteries, kidneys, and other
- organs calcify during aging. At the age of 90, the amount of calcium in the elastic layer of an artery is
- about 35 times greater than at the age of 20. Nearly every type of tissue, including the brain, is
- susceptible to the inflammatory process that leads through fibrosis to calcification. The exception is the
- skeleton, which loses its calcium as the soft tissues absorb calcium. These observations lead to some
- simplifying ideas about the nature of aging and disease. Some people who know about the involvement of
- calcium in aging, stress, and degeneration suggest eating a low calcium diet, but since we all have
- skeletons, dietary calcium restriction cant protect our cells, and in fact, it usually intensifies the
- process of calcification of the soft tissues. Statistics from several countries have clearly shown that the
- mortality rate (especially from arteriosclerotic heart disease, but also from some other diseases, including
- cancer) is lower than average in regions that have hard water, which often contains a very large amount of
- either calcium or magnesium. Many studies have shown that dietary calcium (or vitamin D, which increases
- calcium absorption) can have very important antiinflammatory effects. About 25 years ago, David McCarron
- noticed that the governments data on diet and hypertension showed that the people who ate the most salt had
- the lowest blood pressure, and those who ate the least salt had the highest pressure. He showed that a
- calcium deficiency, rather than a sodium excess, was the most likely nutritional explanation for
- hypertension. Hans Selye found that some steroids contribute to inflammation and calcification. Animals
- could be sensitized to develop calciphylaxis, an intense, localized interaction of inflammation and
- calcification. In the 1970s, Constance Martin pointed out that, up to that time, estrogen was known to
- increase soft tissue calcium, but hadnt been shown to improve bone calcification and strength. Oxygen
- deprivation, cyanide poisoning, x-irradiation, and all other sorts of injury also increase the calcium
- content of soft tissues. One of Selyes colleagues, G. Jasmin, showed that magnesium deficiency causes
- inflammation. A deficiency of either calcium or magnesium can stimulate the parathyroid glands to produce
- more hormone (parathyroid hormone, PTH), which increases calcium absorption, but also removes calcium from
- the bones. This hormone, responding to a dietary calcium or magnesium deficiency, is an important factor in
- causing cells to take up too much calcium, and its excess is associated with many inflammatory and
- degenerative diseases. Interleukin-6 (IL-6), an inflammatory cytokine which increases with aging, is
- commonly considered to have an important role in the multiple processes of atrophy in old age. One of the
- things which can increase the production of IL-6 is the parathyroid hormone (PTH), which increases the
- amount of calcium circulating in the blood, partly by causing it to be removed from the bones; IL-6
- stimulates the process of calcium removal from bones. Some of the interactions of hormones and other
- regulatory chemicals are interesting, even though they are normally treated as if they were parts of a
- machine that operates according to a hidden program written in the genes. Prolactin, which is increased
- under the influence of estrogen or serotonin, causes the body to lose calcium (drawing it from the bones),
- and it stimulates the secretion of PTH, which compensates for the calcium loss by increasing its
- mobilization from bones. Prolactins action on bone is at least partly by increasing IL-6 formation; IL-6
- stimulates the release of prolactin. Serotonin and IL-6 stimulate each others secretion, and PTH and
- serotonin each stimulate the others release.. PTH (like estrogen and serotonin) inhibits cellular
- respiration and activates glycolysis, lowering the ATP level and shifting the cells metabolism toward the
- production of lactic acid rather than carbon dioxide. PTH also causes bicarbonate to be lost in the urine.
- Since the formation of carbon dioxide lowers the intracellular pH, and the formation of lactic acid raises
- it (through the reaction of NADH with pyruvate), the proteins in the cell become more strongly negatively
- charged under the influence of oxygen deprivation, or under the influence of these hormones. In the cell
- with high pH and increased negative electrical charge, the positively charged calcium ion is absorbed into
- the cytoplasm. The calcium can enter from the relatively concentrated external fluid, but it can also be
- released from acidic intracellular stores, the way serotonin is released by a disturbance of pH. There are
- several other pro-inflammatory substances, such as the cytokines, that have a similar effect on cellular
- energy systems. The antimetabolic actions of PTH mimic those seen in aging and diabetes, and surgical
- removal of the parathyroid glands has been known to eliminate diabetes. PTH can cause diuresis, leading to
- loss of blood volume and dehydration, hypertension, paralysis, increased rate of cell division, and growth
- of cartilage, bone, and other tissues. Simply eating an adequate amount of calcium and magnesium can
- alleviate many problems related to stress and aging that are considered serious, such as heart arrhythmia,
- pancreatitis, and tissue calcification. The antiinflammatory, anti-allergy actions of calcium and magnesium
- are well established, and there is clear evidence that obesity and various emotional disturbances can result
- from their deficiency. Chronically high PTH can produce anemia, by a variety of mechanisms. Since a very low
- sodium diet increases the loss of magnesium, by increasing aldosterone synthesis, simply increasing the
- amount of sodium in the diet can help some people to balance their minerals and minimize stress. During
- fasting and other intense stress, the kidneys destroy a large amount of protein to form ammonia to maintain
- their ability to excrete acids, so using a large amount of the alkaline minerals can reduce the protein
- catabolism. A diet of milk and fruit, or milk and meat, provides a nutritional balance with generous amounts
- of calcium and magnesium. Leafy vegetables are a very rich source of magnesium, but they are also a
- potential source of large amounts of lead and other toxins. In 1960, many people, including the
- U.S.government, were advocating the use of a largely vegetarian diet for children, because of the amount of
- radioactive strontium in milk. I compared the amount of strontium in a diet of vegetables that would provide
- the necessary quantity of calcium and protein, and it was clear that vegetables were the worst source of
- radioactive strontium, because their ratio of strontium to calcium was much higher than the ratio in milk.
- The cows were concentrating calcium and protein from the contaminated plant foods, eliminating much of the
- strontium. This principle still applies to the toxins that are currently found in the U.S. food supply. Milk
- has many protective effects besides providing calcium. Many babies are being given milk substitutes (health
- food drinks) made from soy or rice, with terrible consequences. The same products used by adults have less
- disastrous effects in the short term, but are still likely to contribute to degeneration and dementia. Much
- of the intracellular magnesium is complexed with ATP, and helps to stabilize that molecule. If cellular
- energy production is low, as in hypothyroidism, cells tend to lose their magnesium very easily, shifting the
- balance toward the lower energy molecule, ADP, with the release of phosphate. ADP complexes with calcium,
- rather than magnesium, increasing the cells calcium content. Increased intracellular calcium, in association
- with excess nitric oxide and excitatory amino acids, is involved in several neurodegenerative diseases,
- including ALS, Alzheimers disease, Parkinsons disease, Huntingtons chorea, and epilepsy. Magnesium,
- nicotine, progesterone, and many other substances are known to protect against excitotoxic calcium overload,
- but there is no coherent effort in the health professions to make rational use of the available knowledge.
- Respiration and carbon dioxide are the basic antagonists of the PTH. At birth, a baby has practically no
- PTH, probably because of the high intrauterine concentration of carbon dioxide, but within a few days the
- PTH rises. Increased carbon dioxide favors bone formation, and decreased bicarbonate favors the loss of
- calcium from bone (Canzanello, et al., 1995; Bushinsky, et al, 2001). The use of sodium bicarbonate can
- stimulate bone formation. A low protein diet, similar to that eaten by a large proportion of women (0.8 g/kg
- of body weight) increases PTH, and so probably contributes to the development of osteoporosis and the
- diseases of calcification. In an extreme protein deficiency, there is a shift towards inflammation,
- serotonin excess, and excessive clotting, which might be related to the effect of the milder, more common
- protein deficiency. Many people advocate a low protein diet, specifically to prevent or treat osteoporosis,
- but the cultures that traditionally have had extremely high protein diets, such as the Masai, are very
- healthy. Recent studies (see Bell and Whiting, 2002) are emphasizing the importance of animal protein in
- preventing osteoporosis. Traditional meat-eating cultures efficiently use the whole animal, including blood,
- skin, bones, and the various organs, rather than just the muscles. That diet is favorable for calcium
- regulation, because it provides more vitamin A, D, E, and K, calcium, and gelatin, and less of the
- pro-inflammatory amino acids, tryptophan and cysteine. Most loss of calcium from bones occurs during the
- night. PTH tends to cycle with prolactin, which increases during the night, along with cortisol and the
- other stress hormones. These nocturnal hormones probably account for the morning stiffness seen in many
- rheumatic conditions, connective tissue diseases, and in aging. Progesterone, which increases the carbon
- dioxide content of the tissues, is remarkably able to inhibit the actions of most of the inflammatory and
- catabolic mediators, and to protect against degenerative calcification and osteoporosis. It also protects
- against abnormal clotting. PTH increases platelet calcium concentration, and under some conditions can
- produce inappropriate coagulation. Aspirin inhibits the actions of PTH, helping to prevent the calcification
- of inflamed tissues, and it inhibits the loss of calcium from bones. Aspirin decreases the release of IL-6.
- A protein called the PTH-related protein (PTHrP) has the same functions as PTH, but can be produced in any
- tissue. It is responsible for the hypercalcemia of cancer, and is apparently involved in the frequent
- metastasis of breast cancer to the bones. With only a small change in the theory of the nature of a living
- organism, recognizing the importance of the interactions of metabolites and structural substances,
- controlled by energetic metabolism, real progress could be made in understanding disease and health. The
- most important calcium paradox is that medical journals (e.g.,
- <em>International J. of Cardiology, </em>
- Dec., 2002) are still promoting the idea that eating too much calcium causes hardening of the arteries and
- other diseases of calcification.
-
- <h3>REFERENCES</h3>
- </p>
- <p>
- <strong>
- J Am Soc Nephrol 1994 Apr;4(10):1814-9. A role of parathyroid hormone for the activation of cardiac
- fibroblasts in Uremia.</strong> Amann K, Ritz E, Wiest G, Klaus G, Mall G. Thus, PTX abolished and PTH
- restored intermyocardiocytic changes of experimental uremia. These observations argue for a permissive role
- of PTH for fibroblast activation and the genesis of the cardiac fibrosis of uremia.
- </p>
- <p>
- Clin Endocrinol (Oxf) 1976 May;5(3):291-3. Recurrent hormone dependent chorea: effects of oestrogens and
- progestogens. Barber PV, Arnold AG, Evans G.
- </p>
- <p>
- Biochem Biophys Res Commun 2001 Feb 23;281(2):277-81. <strong>17 beta-estradiol increases Ca(2+) influx and
- down regulates interleukin-2 receptor in mouse thymocytes.</strong> Azenabor AA, Hoffman-Goetz L.
- </p>
-
- <p>
- Nutr Rev 2002 Oct;60(10 Pt 1):337-41. Elderly women need dietary protein to maintain bone mass. Bell J,
- Whiting SJ. Researchers who conducted a recent prospective study of older adults reported that animal
- protein had a protective role for bone, especially in elderly women, whereas plant protein was negatively
- associated with bone mineral density. Other studies confirm the beneficial effect of increasing dietary
- protein intake in older women to reduce bone mineral density loss and risk of fracture, suggesting that
- emphasis should be placed on promoting adequate protein intake in elderly women.
- </p>
- <p>
- Am J Physiol Renal Physiol 2001 Dec;281(6):F1058-66. Metabolic, but not respiratory, acidosis increases bone
- PGE(2) levels and calcium release. Bushinsky DA, Parker WR, Alexander KM, Krieger NS. A decrease in blood pH
- may be due to either a reduction in bicarbonate concentration ([HCO(3)(-)]; metabolic acidosis) or to an
- increase in PCO(2) (respiratory acidosis). In mammals, metabolic, but not respiratory, acidosis increases
- urine calcium excretion without altering intestinal calcium absorption, indicating that the additional
- urinary calcium is derived from bone. In cultured bone, chronic metabolic, but not respiratory, acidosis
- increases net calcium efflux (J(Ca)), decreases osteoblastic collagen synthesis, and increases osteoclastic
- bone resorption. Metabolic acidosis increases bone PGE(2) production, which is correlated with J(Ca), and
- inhibition of PGE(2) production inhibits this acid-induced J(Ca). Thus metabolic, but not respiratory,
- acidosis induces the release of bone PGE(2), which mediates J(Ca) from bone.
- </p>
- <p>
- J Clin Endocrinol Metab 1991 Jan;72(1):69-76. Circadian variation in ionized calcium and intact parathyroid
- hormone: evidence for sex differences in calcium homeostasis. Calvo MS, Eastell R, Offord KP, Bergstralh EJ,
- Burritt MF. Serum intact PTH levels showed a significant circadian pattern in both sexes (P less than or
- equal to 0.001).
- </p>
- <p>
- J Lab Clin Med 1995 Jul;126(1):81-7. Effect of chronic respiratory acidosis on calcium metabolism in the
- rat. Canzanello VJ, Kraut JA, Holick MF, Johns C, Liu CC, Madias NE. Chronic metabolic acidosis typically
- results in hypercalciuria and negative calcium balance. The impact of chronic respiratory acidosis on
- calcium metabolism has been less well studied. To address this issue, metabolic balance and static bone
- histomorphometric data were obtained during a 14-day exposure of rats to 10% CO2 (blood pH 7.33, PaCO2 83 mm
- Hg) and were compared with pair-fed controls. All rats were fed a 0.8% calcium diet. Urinary calcium
- excretion (mg/period, mean +/- SEM) was increased during both week 1 and week 2 (16 +/- 3 vs 9 +/- 1 and 16
- +/- 2 vs 9 +/- 1, CO2 group vs controls, respectively [p < 0.05]). Net intestinal calcium absorption
- (intake minus fecal excretion) was increased throughout the period of hypercapnia (week 1, 213 +/- 19 mg vs
- 135 +/- 15 mg; week 2, 135 +/- 16 mg vs 43 +/- 14 mg; and cumulatively, 344 +/- 27 mg vs 178 +/- 20 mg, CO2
- group vs controls [p < 0.01]). As a consequence of the marked increment in intestinal calcium absorption
- during hypercapnia, mean net calcium balance was more positive than that of controls throughout the study
- (week 1, 197 +/- 18 mg vs 126 +/- 15 mg; week 2, 120 +/- 15 mg vs 34 +/- 15 mg; and cumulatively, 317 +/- 25
- mg vs 159 +/- 20 mg, CO2 group vs controls, respectively [p < 0.01]). There were no significant
- differences in calcium intake, plasma total calcium, immunoreactive parathyroid hormone, 25-hydroxyvitamin
- D, or creatinine clearance between the two groups.
- </p>
-
- <p>
- Mov Disord 1991;6(4):355-7. An unusual cause of recurrent chorea. Caviness JN, Muenter MD. Lee Silverman
- </p>
- <p>
- Bone 2000 Jan;26(1):79-85. <strong>
- Correlation of estradiol, parathyroid hormone, interleukin-6, and soluble interleukin-6 receptor during
- the normal menstrual cycle.</strong> Chiu KM, Arnaud CD, Ju J, Mayes D, Bacchetti P, Weitz S, Keller ET.
- <strong><hr /></strong>
- <hr />
- <strong>These data demonstrate that IL-6 and PTH fluctuate with E2, and serum II-6 is associated with PTH
- levels during the menstrual cycle.
- </strong>
- </p>
- <p>
- J Cell Sci 2002 Feb 1;115(Pt 3):599-607. pH-dependent regulation of lysosomal calcium in macrophages.
- Christensen KA, Myers JT, Swanson JA. Average free calcium concentration in macrophage lysosomes was
- 4-6x10(-4) M, less than half of the extracellular calcium concentration, but much higher than cytosolic
- calcium levels. pH-dependent reductions of lysosomal calcium concentrations appeared to result from calcium
- movement out of lysosomes into cytoplasm, since increases in cytosolic calcium levels could be detected upon
- lysosome alkalinization.
- </p>
- <p>
- Adv Neurol 1979;26:123-33. Ovarian steroid hormones and cerebral function. Cogen PH, Zimmerman EA.
- </p>
- <p>
- J Bone Miner Res 1996 Oct;11(10):1419-29. Stimulation of neonatal mouse calvarial bone resorption by the
- glucocorticoids hydrocortisone and dexamethasone. Conaway HH, Grigorie D, Lerner UH. In vitro stimulation of
- bone resorption was observed with the glucocorticoids hydrocortisone and dexamethasone. The 45Ca release
- stimulated by 1 microM hydrocortisone and 0.1 microM dexamethasone was also inhibited by 10 microM
- progesterone in a competitive manner and by 1 microM of the antiglucocorticoid RU38486, both of which are
- modulators of glucocorticoid binding.
- </p>
- <p>
- J Physiol 2002 Mar 15;539(Pt 3):791-803. MgATP counteracts intracellular proton inhibition of the
- sodium-calcium exchanger in dialysed squid axons. DiPolo R, Beauge L. The increase in Ca(2+)(i) affinity
- induced by ATP at acid pH (6.9) can be mimicked by a rise in pH(i) from 6.9 to 7.3 in the absence of the
- nucleotide.
- </p>
- <p>
- J Maine Med Assoc 1977 Oct;68(10):370-1 Quadriparesis as an unusual manifestation of hypercalcemia. Dyro FM.
- </p>
- <p><hr /></p>
-
- <p>
- Hypertension 1986 Jun;8(6):497-505. Effects of calcium infusion on blood pressure in hypertensive and
- normotensive humans. Ellison DH, Shneidman R, Morris C, McCarron DA. Together, these data provide evidence
- for interactions between dietary sodium intake and the cardiovascular response to calcium. They confirm that
- hypertensive subjects exhibit enhanced parathyroid gland function even when dietary factors are controlled,
- and they suggest that these subjects are more sensitive to the cardiovascular effects of short-term calcium
- infusion.
- </p>
- <p>
- Yale J Biol Med 1996 Sep-Dec;68(5-6):215-7. Diplopia associated with hyperparathyroidism: report of a case.
- Forman BH, Ciardiello K, Landau SJ, Freedman JK. A patient with hypercalcemia due to primary
- hyperparathyroidism presented with diplopia that resolved with surgical removal of his parathyroid adenoma
- and normalization of his serum calcium values. No previous report of this feature of hyperparathyroidism has
- been reported.
- </p>
- <p>
- J Nutr Sci Vitaminol (Tokyo) 1985 Dec;31 Suppl:S15-9. <strong>Aging and calcium as an environmental
- factor.</strong>
- Fujita T Calcium deficiency is a constant menace to land-abiding animals, including mammals. Humans enjoying
- exceptional longevity on earth are especially susceptible to calcium deficiency in old age. Low calcium and
- vitamin D intake, short solar exposure, decreased intestinal absorption, and falling renal function with
- insufficient 1,25(OH)2 vitamin D biosynthesis all contribute to calcium deficiency, secondary
- hyperparathyroidism, bone loss and possibly calcium shift from the bone to soft tissue, and from the
- extracellular to the intracellular compartment, blunting the sharp concentration gap between these
- compartments. The consequences of calcium deficiency might thus include not only osteoporosis, but also
- arteriosclerosis and hypertension due to the increase of calcium in the vascular wall, <strong>amyotrophic
- lateral sclerosis and senile dementia due to calcium deposition
- </strong>in the central nervous system, <strong>and a decrease in cellular function, because of blunting of
- the difference in extracellular-intracellular calcium, leading to diabetes mellitus, immune deficiency
- and others (Fig. 6)
- </strong>
- </p>
- <p>
- Ann N Y Acad Sci 1990;587:371-5. Cytokines and osteoporosis. Fujita T, Matsui T, Nakao Y, Shiozawa S, Imai
- Y. Conditions associated with immune dysfunction such as aging, corticosteroid therapy, and rheumatoid
- arthritis are associated with osteoporosis, which is also more common in females than in males, like most of
- the autoimmune-collagen diseases. Peripheral lymphocyte subsets CD4/CD8 were higher in patients with senile
- osteoporosis than in the age-matched controls, and returned to normal after 1 month of 1 alpha(OH)vitamin D3
- treatment. Plasma interferon reflecting macrophage function decreased with advance in age and increased in
- response to 1 alpha(OH)D3 treatment. As one of the immunoregulators, vitamin D tends to stimulate the
- macrophage-natural killer system and suppress the lymphocyte system, stimulating TGF beta and TNF alpha
- activity. Senile osteoporosis of low turnover thus appears to be associated with vitamin D deficiency, low
- macrophage function, high CD4 lymphocyte proportion, low IL-1 and high IL-2 activity, low IFN alpha and high
- IFN gamma activity, and low TGF beta and TNF alpha activity.
- </p>
-
- <p>
- Contrib Nephrol 1991;90:206-11. <strong>
- Calcium, parathyroids and aging.
- </strong>
- Fujita T Calcium is unique in its distribution in living organisms with an extremely high hard and soft
- tissue and extra- intracellular concentration gradient. Calcium<strong>
- deficiency through stimulating parathyroid hormone secretion tends to blunt such a difference by
- paradoxically increasing the calcium concentration in the soft tissue and intracellular compartment.
- Since aging is associated with the</strong> progressive aggravation of calcium deficiency, such blunting
- also progresses with aging. The dysfunction, damage and death of cells occurring in all diseases<strong>
- is always associated with a blunting of the extra- and intracellular calcium components. Calcium
- supplement especially with highly biologically available active absorbable calcium, was associated with
- the suppression of parathyroid</strong>
- hormone secretion and the normalization of a such blunting <strong>of intercompartmental distribution of
- calcium examples in hypertension and diabetes mellitus with evident improvement of clinical
- manifestations and laboratory tests.
- </strong>
- </p>
- <p>
- Presse Med 2001 Apr 7;30(13):653-8. [Hypovitaminosis D: a major worldwide public health problem]
- Gannage-Yared MH, Tohme A, Halaby G. Mild to moderate hypovitaminosis D causes secondary hyperparathyroidism
- increasing the risk of fracture, particularly femoral neck fracture. Vitamin D would also have an
- antiinflammatory and anticancer effect. Hypovitaminosis D is frequently observed in Europe in the elderly,
- particularly in the institutionalized population, but is also seen in otherwise healthy younger adults. An
- estimated 40% of the young European population has some degree of hypovitaminosis D. Finally, the beneficial
- effect of moderate sun exposure on cutaneous vitamin D synthesis (and psychological well-being) must not be
- overlooked.
- </p>
- <p>
- Mol Med 1996 Mar;2(2):204-10. <strong>
- Parathyroid hormone-related protein is induced during lethal endotoxemia and contributes to
- endotoxin-induced mortality in rodents.</strong> Funk JL, Moser AH, Strewler GJ, Feingold KR, Grunfeld
- C. Parathyroid hormone-related protein (PTHrP) is a ubiquitous and highly conserved vasoactive peptide whose
- role and regulation in normal physiology remain an enigma. Recently, we demonstrated that low-dose endotoxin
- (LPS) induces intrasplenic, but not systemic, levels of PTHrP; and that tumor necrosis factor, a
- pro-inflammatory cytokine, is the major mediator of this effect. We have therefore hypothesized that, with
- higher, lethal doses of endotoxin, PTHrP could be induced in multiple tissues to such a degree that it could
- contribute to the lethality of septic shock. In response to a near-lethal dose of endotoxin, PTHrP mRNA
- levels increased acutely in every vital organ examined (spleen, lung, heart, kidney, and liver). Circulating
- levels of PTHrP also increased, peaking 2 hr after administration of high-dose endotoxin. These<strong>
- results suggest that PTHrP belongs to the cascade of pro-inflammatory cytokines induced during lethal
- endotoxemia that is responsible for the toxic effects of</strong> LPS.
- </p>
- <p><hr /></p>
- <p>
- Calcif Tissue Int 1990 May;46(5):294-9. Effective therapy of glucocorticoid-induced osteoporosis with
- medroxyprogesterone acetate. Grecu EO, Weinshelbaum A, Simmons R. The results lend support to the hypothesis
- of a progesterone-glucocorticoid competitive antagonism at the bone level, though other possibilities can be
- entertained, and suggest MPA as an effective therapy for glucocorticoid-induced osteoporosis in men.
- </p>
-
- <p>
- Proc Soc Exp Biol Med 1986 Mar;181(3):438-42. <strong>Forskolin-induced bone resorption in neonatal mouse
- calvaria in vitro.</strong> Gunasekaran S, Hall GE, Kenny AD <strong>Lactic acid release was increased
- during the 96 hr of incubation in proportion to the calcium release in the media.</strong>
-
- J Endocrinol 2000 Feb;164(2):129-38. <strong>Estrogen mediates the sex difference in post-burn
- immunosuppression.</strong> Gregory MS, Duffner LA, Faunce DE, Kovacs EJ. Previous studies in our
- laboratory have demonstrated that cell-mediated immune function was suppressed in female, but not male, mice
- at 10 days after burn injury and was mediated,<strong>
- in part, by increased production of interleukin-6 (IL-6).
- </strong>
- Increased circulating<strong>
- concentrations of E(2) corresponded with suppressed delayed-type hypersensitivity (DTH) and
- splenocyte-proliferative responses, and increased circulating concentrations of IL-6 in female mice
- after burn. Ovariectomy
- </strong>restored the suppressed DTH response and decreased IL-6 concentrations, and administration of
- exogenous E(2) to both ovariectomized females and intact male mice resulted in a suppressed DTH response. In
- addition, in vitro <strong>treatment with E(2) suppressed splenocyte proliferation in a macrophage-dependent
- manner and enhanced macrophage production of IL-6.</strong>
- </p>
-
- <p>
- Calcif Tissue Int 1990 May;46(5):294-9. Effective therapy of glucocorticoid-induced osteoporosis with
- medroxyprogesterone acetate. Grecu EO, Weinshelbaum A, Simmons R.
- </p>
- <p>
- Nephron 1982;30(3):237-9. Elevated thrombocyte calcium content in uremia and its correction by 1 alpha(OH)
- vitamin D treatment. Gura V, Creter D, Levi J.
- </p>
- <p>
- Fortschr Med 1985 Mar 28;103(12):328-30. <strong>
- [Antiallergic effect of oral calcium.</strong> A clinico-experimental study] [Article in German] Haas
- PJ. Randomized Controlled Trial
- </p>
- <p>
- Acta Univ Carol Med Monogr 1972;53:427-32. The possible role of platelets as trigger in intravascular
- coagulation associated with acute hyperparathyroidism. Hilgard P, Hohage R, Schmitt W, Minne H, Ziegler R.
- </p>
-
- <p>
- Sci Total Environ 1986 Oct;54:207-16. Chemical qualities of water that contribute to human health in a
- positive way. Hopps HC, Feder GL. The chemical substances in water that make positive contributions to human
- health act mainly in two ways: (i) nutritionally, by supplying essential macro and micro elements that the
- diet (excluding water) may not provide in adequate amounts (for example, Mg, I and Zn); and (ii) by
- providing macro and micro elements that inhibit the absorbtion and/or effects of toxic elements such as Hg,
- Pb and Cd. In this context, the inverse relationship between hard water and cardiovascular disease will be
- discussed. Specific data relating hardness and Mg and Ca content of potable waters to specific geographic
- regions of the U.S.A. will be presented. These data show a strong positive correlation between low Mg
- content and decreased longevity, and between high Ca and Mg content and increased longevity. In the regions
- considered, increased longevity correlates strongly with decreased cardiovascular mortality, and the
- decreased longevity with increased cardiovascular mortality.
- </p>
- <p>
- Calcif Tissue Res 1977 Oct 20;23(3):241-4.<strong>
- Proliferation of osteoclasts in rat bone following bleeding and femoral fractures.</strong> Johnell O,
- Hulth A This rise in the osteoclast population might be due to an increased parathyroid activity released by
- the trauma, but other factors may be involved. Both bleedings and fractures in rats are followed by
- hypercalcemia. Brain Behav Immun 2000 Mar;14(1):49-61. <strong>Modulation of IL-6 production during the
- menstrual cycle in vivo and in vitro.</strong> Konecna L, Yan MS, Miller LE, Scholmerich J, Falk W,
- Straub RH. Premenopausal female patients with chronic inflammatory diseases demonstrate changes in disease
- activity during the MC. <strong><hr /></strong>
- <hr />
-
- Kidney Int Suppl 1983 Dec;16:S204-7. <strong>Pathogenesis of the anemia of uremia: role of secondary
- hyperparathyroidism.</strong> Massry SG PTH may participate in the genesis of the anemia of uremia
- through at least<strong>
- three pathways. These include inhibition of erythropoiesis, shortening survival of RBCs and inducing
- fibrosis of bone marrow cavity.
- </strong>
- </p>
- <p>
- Braz J Med Biol Res 2002 Feb;35(2):229-36. Parathyroid hormone secretion in chronic human endogenous
- hypercortisolism. Lanna CM, Paula FJ, Montenegro RM Jr, Moreira AC, Foss MC. Osteoporosis is a common
- manifestation of Cushing's syndrome, but the mechanisms responsible for this abnormality have not been
- defined. Patients with CH showed an increased PTH response to the hypocalcemic stimulus compared to
- controls.
- </p>
- <p>
- Am J Clin Nutr 2000 Jul;72(1):168-73. <strong>
- A threshold for low-protein-diet-induced elevations in parathyroid hormone.</strong>
-
- Kerstetter JE, Svastisalee CM, Caseria DM, Mitnick ME, Insogna KL. <strong>
- Elevations in PTH developed by day 4 of the diets containing 0.7 and 0.8 g protein/kg but not during the
- diets containing 0.9 or 1.0 g protein/kg.</strong>
- Our data suggest that in young healthy women consuming a well-balanced diet, the current recommended dietary
- allowance for protein (0.8 g/kg) results in short-term perturbations in calcium homeostasis.
- </p>
- <p>
- J Endocrinol 1995 Sep;146(3):421-9. Effect of oral calcium supplementation on intracellular calcium and
- plasma renin in men. Lijnen P, Petrov V. Oral calcium supplementation in these men was also accompanied by a
- reduction in the plasma concentration of intact parathyroid hormone and 1,25-dihydroxyvitamin D3, an
- increase in 24-h urinary calcium excretion but no change in the plasma total Ca2+ concentration, serum
- ionized Ca2+ level and plasma phosphate or 25-hydroxyvitamin D3.
- </p>
- <p>
- Clin Sci (Lond) 1996 Sep;91(3):313-8. Effects of mineral composition of drinking water on risk for stone
- formation and bone metabolism in idiopathic calcium nephrolithiasis. Marangella M, Vitale C, Petrarulo M,
- Rovera L, Dutto F. The increase in overall calcium intake due to different drinking water induced modest
- increases in calcium excretion, whereas oxalate excretion tended to decrease. The changes in oxalate
- excretion during any one study period compared with another were significantly related to those in calcium
- intake. Citrate excretion was significantly higher with the high-calcium, alkaline water. 4. Parathyroid
- hormone, calcitriol and markers of bone resorption increased when patients were changed from the
- high-calcium, alkaline to the low-calcium drinking water. 5. We suggest that overall calcium intake may be
- tailored by supplying calcium in drinking water. Adverse effects on bone turnover with low-calcium diets can
- be prevented by giving high-calcium, alkaline drinking water, and the stone-forming risk can be decreased as
- effectively as with low-calcium drinking water.
- </p>
- <p>
- J Endocrinol 1998 Feb;156(2):231-5. Calcium blood level modulates endogenous nitric oxide action: effects of
- parathroidectomy in patients with hyperparathyroidism. Martina V, Bruno GA, Brancaleoni V, Zumpano E,
- Tagliabue M, Fornengo R, Gasparri G, Pescarmona GP. In primary hyperparathyroidism (H-PTH) an increase in
- platelet free calcium levels is present. After surgery, together with the normalization of calcium levels,
- NO production also returned to normal values.
- </p>
-
- <p>
- Hypertension 1980 Mar-Apr;2(2):162-8. Enhanced parathyroid function in essential hypertension: a homeostatic
- response to a urinary calcium leak. McCarron DA, Pingree PA, Rubin RJ, Gaucher SM, Molitch M, Krutzik S.
- Recent reports . . . suggest that increased parathyroid gland function may be one of the more common
- endocrine disturbances associated with hypertension. Compared to a second age- and sex-matched normotensive
- population, the hypertensives demonstrated a significant (p less than 0.005) relative hypercalciuria. For
- any level of urinary sodium, hypertensives excreted more calcium. These preliminary data suggest that
- parathyroid gland function may be enhanced in essential hypertension.
- </p>
- <p>
- Am J Med 1987 Jan 26;82(1B):27-33. The calcium paradox of essential hypertension. McCarron DA, Morris CD,
- Bukoski R. Three disparate observations--that calcium mediates vascular smooth muscle contraction, that
- calcium channel blockers lower blood pressure, and that increased dietary calcium intake can also ameliorate
- hypertension--constitute somewhat of a paradox. This evidence, and the paradoxical therapeutic efficacy of
- both calcium channel blockers and supplemental dietary calcium, can be integrated into a single theoretic
- construct.
- </p>
- <p>
- Am J Hypertens 1995 Oct;8(10 Pt 1):957-64. Regulation of parathyroid hormone and vitamin D in essential
- hypertension. Young EW, Morris CD, Holcomb S, McMillan G, McCarron DA. The maximal stimulated PTH level was
- significantly higher in hypertensive than normotensive subjects in the absence of measured differences in
- serum ionized calcium concentration, serum 1,25(OH)2-vitamin D concentration, and creatinine clearance.
- </p>
- <p>
- J Clin Invest 1995 Apr;95(4):1933-40. <strong>
- The diurnal rhythm of bone resorption in the rat. Effect of feeding habits and pharmacological
- inhibitors.</strong> Muhlbauer RC, Fleisch H. This paper shows that, in rats, bone mass can be<strong>
- increased by feeding habits per se. . . . we previously found a peak of bone resorption following food
- administration. We now demonstrate that dividing the solid and liquid intake into portions blunts this
- peak ....
- </strong>
-
- Whether bone mass in humans is also under the control of dietary habits is not known. <strong>If so, an
- increased meal frequency may be used to prevent osteoporosis.
- </strong>Nephron 2001 Dec;89(4):384-90. <strong>Prolonged dietary calcium restriction: a diagnostic approach
- in idiopathic Hypercalciuria.</strong> Muller D, Eggert P.
- </p>
- <p><hr /></p>
-
- <p>
- J Appl Physiol 2001 Jun;90(6):2094-100. Effects of hypercapnia and hypocapnia on [Ca2+]i mobilization in
- human pulmonary artery endothelial cells. Nishio K, Suzuki Y, Takeshita K, Aoki T, Kudo H, Sato N, Naoki K,
- Miyao N, Ishii M, Yamaguchi K. Hypocapnic alkalosis caused a fivefold increase in [Ca2+]i compared with
- hypercapnic acidosis. The hypocapnia-evoked increase in [Ca2+]i was decreased from 242 +/- 56 to 50 +/- 32
- nmol/l by the removal of extracellular Ca2+. The main mechanism affecting the hypocapnia-dependent [Ca2+]i
- increase was thought to be the augmented influx of extracellular Ca2+ mediated by extracellular alkalosis.
- Hypercapnic acidosis caused little change in PGI2 production, but hypocapnic alkalosis increased it
- markedly.
- </p>
- <p>
- Clin Nephrol 2002 Mar;57(3):183-91.. Bone involvement in idiopathic hypercalciuria. Misael da Silva AM, dos
- Reis LM, Pereira RC, Futata E, Branco-Martins CT, Noronha IL, Wajchemberg BL, Jorgetti V. A negative
- correlation was observed between IL-6 levels and Z score of the femoral neck. Bone involvement was detected
- in a young population with nephrolithiasis demonstrating that a strict follow-up is necessary in order to
- control hypercalciuria.
- </p>
- <p>
- Am J Physiol Heart Circ Physiol 2002 Jul;283(1):H193-203. CaMKII-dependent reactivation of SR Ca(2+) uptake
- and contractile recovery during intracellular acidosis. Nomura N, Satoh H, Terada H, Matsunaga M, Watanabe
- H, Hayashi H. In hearts, intracellular acidosis disturbs contractile performance by decreasing myofibrillar
- Ca(2+) response, but contraction recovers at prolonged acidosis.
- </p>
- <p>
- J R Soc Health 1998 Apr;118(2):103-6. Lessons to be learned: a case study approach. Primary
- hyperparathyroidism simulating an acute severe polyneuritis. Olukoga A. The case is presented of a 65 year
- old lady with recent onset of neuromuscular manifestations, comprising paraparesis, areflexia and unsteady
- gait, along with episodes of slurring of speech and diplopia, later confirmed to be due to severe
- hypercalcaemia--which itself was caused by primary hyperparathyroidism.
- </p>
-
- <p>
- Nippon Ronen Igakkai Zasshi 1989 May;26(3):216-22. <strong>[Calcium and magnesium metabolism in the
- aged]</strong>
- [Article in Japanese] Ouchi Y, Orimo H Although serum calcium concentration remains constant during ageing,
- the plasma<strong>
- concentration of calcium regulating hormones has been known to show dramatic change with ageing. The
- plasma concentration of parathyroid hormone increases with ageing, whereas plasma concentrations of
- calcitonin and active vitamin D metabolite decrease with ageing.</strong> On the other hand, the
- incidence of <strong>soft tissue calcification is known to increase with ageing.
- </strong>
- </p>
- <p>
- J Clin Endocrinol Metab 1978 Sep;47(3):626-32. Calcium-regulating hormones during the menstrual cycle.
- Pitkin RM, Reynolds WA, Williams GA, Hargis GK. In six subjects with cycle lengths of 27-31 days, PTH levels
- rose progressively through the follicular phase to a peak at or slightly before the LH surge, then fell
- progressively through the luteal phase; peak PTH levels were 30-35% above early follicular and late luteal
- values. One subject experienced a prolonged (44 day) ovulatory cycle characterized by three distinct PTH
- peaks, each of which coincided with elevations in plasma estradiol level.
- </p>
- <p>
- Muscle Nerve 1982 Jan;5(1):26-32. <strong>
- Hereditary polymyopathy and cardiomyopathy in the Syrian hamster. II. Development of heart necrotic
- changes in relation to defective mitochondrial function.</strong> Proschek L, Jasmin G <strong>Since the
- mitochondrial respiratory pattern and calcium overload parallel the cardiac degeneration, it is inferred
- that the cell energy depletion is a functional consequence of an abnormal calcium influx.</strong>
-
- Eur J Endocrinol 1998 Oct;139(4):433-7. <strong>Changes in cytochrome oxidase activity in brown adipose
- tissue during oestrous cycle in the rat.</strong>
- Puerta M, Rocha M, Gonzalez-Covaleda S, McBennett SM, Andrews JF. <strong>
- The involvement of oestradiol in such a cycle is suggested by the fact that oestradiol treatment
- decreased COX activity to values similar to those found in proestrus.
- </strong>
- </p>
- <p>
- Am J Hypertens 1999 Dec;12(12 Pt 1-2):1217-24. Modification of intracellular calcium and plasma renin by
- dietary calcium in men. Petrov V, Lijnen P. Our data show that the increase in PARA [plasma renin activity]
- observed in men during oral calcium supplementation is accompanied by a reduction in the intracellular free
- and total Ca2+ concentration in platelets and erythrocytes and by a decrease in the plasma concentration of
- intact parathormone and 1,25-dihydroxyvitamin D3.
- </p>
- <p>
- Arthritis Rheum 2001 Oct;44(10):2338-41. <strong>
- Association of osteoporosis and cardiovascular disease in women with systemic lupus
- erythematosus.</strong> Ramsey-Goldman R, Manzi S. These results demonstrate an association between
- decreased BMD and both an increased carotid plaque index and presence of coronary artery calcification in a
- small cohort of young women with lupus.
- </p>
-
- <p>
- Am J Hypertens 1994 Dec;7(12):1052-7. Dietary calcium reduces blood pressure, parathyroid hormone, and
- platelet cytosolic calcium responses in spontaneously hypertensive rats. Rao RM, Yan Y, Wu Y.
- </p>
- <p>
- J Clin Endocrinol Metab 2002. May;87(5):2008-12 Potassium citrate prevents increased urine calcium excretion
- and bone resorption induced by a high sodium chloride diet. Sellmeyer DE, Schloetter M, Sebastian A.
- </p>
- <p>
- J Allergy Clin Immunol 1990 Dec;86(6 Pt 1):881-5 <strong>1,25-Dihydroxyvitamin D3 potentiates the decreased
- response of lymphocytes from atopic subjects to agents that increase intracellular cyclic adenosine
- monophosphate.</strong> Ravid A, Tamir R, Liberman UA, Rotem C, Pick AI, Novogrodsky A, Koren R. Eur J
- Endocrinol 2002 May;146(5):635-42. <strong>Diurnal rhythm of plasma 1,25-dihydroxyvitamin D and vitamin
- D-binding protein in postmenopausal women: relationship to plasma parathyroid hormone and calcium and
- phosphate metabolism.</strong> Rejnmark L, Lauridsen AL, Vestergaard P, Heickendorff L, Andreasen F,
- Mosekilde L. <strong>With the disclosure of a diurnal rhythm of total plasma 1,25(OH)(2)D, all major
- hormones and minerals related to calcium homeostasis have now been shown to exhibit diurnal variations.
- </strong>
- </p>
-
- <p>
- Magnes Res 1999 Dec;12(4):257-67. Magnesium deficiency-induced osteoporosis in the rat: uncoupling of bone
- formation and bone resorption. Rude RK, Kirchen ME, Gruber HE, Meyer MH, Luck JS, Crawford DL. Magnesium
- (Mg) intake has been linked to bone mass and/or rate of bone loss in humans. Experimental Mg deficiency in
- animal models has resulted in impaired bone growth, osteopenia, and increased skeletal fragility.
- </p>
- <p>
- Schweiz Med Wochenschr 1994 Jun 25;124(25):1122-8. <strong>[Hypercalcemia]</strong> Schmid C. <strong>Severe
- hypercalcemia is mainly caused by inappropriately high concentrations of compounds which promote bone
- resorption, in particular PTH, PTHrP, or 1,25 (OH)2D3. The major consequences are impaired central
- nervous system and kidney function (polyuria/dehydration);
- </strong>
- the latter, in turn, aggravate hypercalcemia via decreased fluid intake, mobility, and renal calcium
- clearance.
- </p>
- <p>
- J Neurophysiol 2002 May;87(5):2209-24. Intracellular pH response to anoxia in acutely dissociated adult rat
- hippocampal CA1 neurons. Sheldon C, Church J. During perfusion with HCO/CO(2)- or HEPES-buffered media (pH
- 7.35) at 37 degrees C, 5- or 10-min anoxic insults were typified by an intracellular acidification on the
- induction of anoxia, a subsequent rise in pH(i) in the continued absence of O(2), and a further internal
- alkalinization on the return to normoxia. Reducing extracellular pH from 7.35 to 6.60, or reducing ambient
- temperature from 37 degrees C to room temperature, also attenuated the increases in steady-state pH(i)
- observed during and after anoxia and reduced rates of pH(i) recovery from acid loads imposed in the
- immediate postanoxic period. The results suggest that a Zn(2+)-sensitive acid efflux mechanism, possibly a
- H(+)-conductive pathway activated by membrane depolarization, contributes to the internal alkalinization
- observed during anoxia in adult rat CA1 neurons. The rise in pH(i) after anoxia reflects acid extrusion via
- the H(+)-conductive pathway and also Na(+)/H(+) exchange, activation of the latter being mediated, at least
- in part, through a cAMP-dependent signaling pathway.
- </p>
- <p>
- Am J Physiol Heart Circ Physiol 2002 Dec;283(6):H2518-26. pH-induced changes in calcium: functional
- consequences and mechanisms of action in guinea pig portal vein. Smith RD, Eisner DA, Wray S. The effects of
- changing extracellular (pH(o)) and intracellular pH (pH(i)) on force and the mechanisms involved in the
- guinea pig portal vein were investigated to better understand the control of tone in this vessel. When pH(o)
- was altered, the effects on force and calcium were the same irrespective of whether force had been produced
- spontaneously by high-K depolarization or by norepinephrine; alkalinization increased tone, and
- acidification reduced it. Because pH(o) changes also lead to changes in pH(i), we determined whether the
- effects on force could be explained by these induced pH(i) changes. It was found, however, that only with
- spontaneous activity did intracellular alkalinization increase force. In depolarized preparations, force was
- decreased, and, with norepinephrine, force was initially decreased and then increased. Thus the effects of
- pH(o) cannot be explained solely by changes in pH(i). The role of the sarcoplasmic reticulum (SR) and
- surface membrane Ca(2+)-ATPase on the mechanism were investigated and shown not to be involved. Therefore,
- it is concluded that both pH(o) and pH(i) can have powerful modulatory effects on portal vein tone, that
- these effects are not identical, and that they are likely to be due to effects of pH on ion channels rather
- than the SR or plasma membrane Ca(2+)-ATPase.
- </p>
-
- <p>
- Biochem Biophys Res Commun 2002 May 10;293(3):974-8. Arachidonic acid increases intracellular calcium in
- erythrocytes. Soldati L, Lombardi C, Adamo D, Terranegra A, Bianchin C, Bianchi G, Vezzoli G.. Since
- arachidonic acid and other polyunsaturated fatty acids influence the activities of most ion channels, we
- studied their effects on the erythrocyte Ca(2+) influx. AA (5-50 microM) and EPA (20-30 microM) stimulated a
- concentration-dependent increase in [Ca(2+)](i), deriving from extracellular calcium (1 mM), without
- affecting the intra- and extracellular pH and membrane voltage. We conclude that AA could activate an
- erythrocyte voltage-independent Ca(2+) transport via an intermediate product of cyclooxygenase pathway...
- </p>
- <p>
- BMJ 1991 Mar 30;302(6779):762. Hormone replacement therapy induced chorea. Steiger MJ, Quinn NP. University
- Department of Clinical Neurology, Institute of Neurology, London.
- </p>
- <p>
- Nippon Naibunpi Gakkai Zasshi 1991 Dec 20;67(12):1319-38. [Cation metabolism and the effects of circulating
- factors in pregnancy induced hypertension] Takashima M, Morikawa H, Yamasaki M, Mochizuki M. These data
- suggest that the increase of p-[Ca2+]i and r-[Na+]i in PIH is important in the initiation and maintenance of
- hypertension by influencing peripheral vascular resistance, and also various factors in the serum of PIH
- women may contribute to the accumulation of intracellular ionized calcium in patients with PIH.
- </p>
- <p>
- Hear Res 2001 Apr;154(1-2):81-7. Effects of gentamicin and pH on [Ca2+]i in apical and basal outer hair
- cells from guinea pigs. Tan CT, Lee SY, Yao CJ, Liu SH, Lin-Shiau SY. By means of fura-2
- microspectrofluorimetry, we measured the intracellular calcium concentration ([Ca2+]i) of OHCs bathed in
- Hanks' balanced salt solution (pH 7.40) during either a resting state or high K+-induced depolarization.
- While gentamicin and extracellular acidification (pH 7.14) can separately attenuate this increase in [Ca2+]i
- in both types of OHCs, their suppressive effects are additive in basal OHCs, but not in apical OHCs.
- </p>
-
- <p>
- Biochem Pharmacol 1983 Jan 15;32(2):355-60. Induction of mast cell secretion by parathormone. Tsakalos ND,
- Theoharides TC, Kops SK, Askenase PW. The biologically active fragment of human parathormone (PTH) and
- intact bovine PTH were found to induce secretion of both serotonin and histamine from rat peritoneal mast
- cells in vitro. Intradermal injection of PTH induced immediate increases in vascular permeability suggesting
- that PTH could induce mast cell secretion in vivo. These results demonstrate that elevated levels of PTH can
- induce mast cell secretion in vitro and in vivo and suggest a possible role for mast cells in the
- pathophysiology of non-allergic disease states.
- </p>
- <p>
- J Neurol Sci 1989 Feb;89(2-3):189-97. Hyperestrogenemia in neuromuscular diseases. Usuki F, Nakazato O,
- Osame M, Igata A. The cases, comprising bulbospinal muscular disease of the Kennedy-Alter-Sung type,
- Kugelberg-Welander disease, amyotrophic lateral sclerosis, and Duchenne muscular dystrophy, were all
- euthyroid males. The baseline levels of serum estrone were significantly higher in all of the patients than
- in age-matched normal subjects. Serum baseline testosterone, LH and FSH levels were all essentially normal,
- except low FSH levels in Duchenne muscular dystrophy.
- </p>
- <p>
- MMW Munch Med Wochenschr 1976 Oct 22;118(43):1395-8. <strong>[Oral application of calcium and vitamin D2 in
- allergic bronchial asthma</strong>] Utz G, Hauck AM. Within 60 minutes after application, a
- statistically significant reduction of airway resistance (Rt) and intrathoracic gas volume (IGV), as well as
- an increase of forced exspiratory one second volume (FEV1) and forced inspiratory one second volume (FIV1)
- was observed, in comparison with placebo. <strong>It is concluded that calcium, given orally in combination
- with calciferol, causes a decrease of airway obstruction in patients with allergic bronchial asthma.
- </strong>J Urol 1994 Oct;152(4):1226-8. <strong>Urinary incontinence due to idiopathic hypercalciuria in
- children.
- </strong>Vachvanichsanong P, Malagon M, Moore ES. In addition to being the most common cause of
- microhematuria in children, our study demonstrates that idiopathic<strong>
- hypercalciuria is also frequently associated with urinary incontinence of all types.
- </strong>Magnes Trace Elem 1991-92;10(2-4):281-6. <strong>Relation of magnesium to osteoporosis and calcium
- urolithiasis.</strong> Wallach S Magnesium influences mineral metabolism in hard and soft tissues
- indirectly through hormonal and other modulating factors, and by direct effects on the processes of bone
- formation and resorption and of crystallization (mineralization). Its causative and therapeutic
- relationships to calcium urolithiasis (CaUr) are controversial despite an association between low urinary Mg
- and CaUr. Recent studies have also found a tendency to low serum and/or lymphocyte Mg levels in CaUr.
- Despite earlier studies demonstrating an inhibitory effect of Mg supplementation on experimental CaUr in
- animals and in spontaneous CaUr in humans, at least two properly controlled clinical trials of Mg
- supplementation have failed to demonstrate a beneficial effect on CaUr frequency. With regard to the
- skeleton, experimental studies have shown that Mg depletion causes a decrease in both osteoblast and
- osteoclast activity with the development of a form of 'aplastic bone disease'. At the same time, bone salt
- crystallization is enhanced by Mg deficiency. Conversely, Mg excess impairs mineralization with the
- development of an osteomalacia-like picture, and may also stimulate bone resorption independently of
- parathyroid hormone. Whether or not Mg depletion may be a causal factor in human osteoporosis is also
- controversial, and there are conflicting reports as to the Mg content of osteoporotic bone. Small decreases
- in serum and/or erythrocyte Mg in osteoporotic patients have been reported, and one author has noted
- improved bone mineral density with a multinutrient supplement rich in Mg. The extant data are sparse and
- indicate a clear need for more rigorous study.
- </p>
- <p>
- Semin Dial 2002 May-Jun;15(3):172-86 Calciphylaxis: emerging concepts in prevention, diagnosis, and
- treatment. Wilmer WA, Magro CM. Several recent reports demonstrate that prolonged hyperphosphatemia and/or
- elevated calcium x phosphorus products are associated with the syndrome. Protein malnutrition increases the
- likelihood of calciphylaxis, as does warfarin use and hypercoagulable states, such as protein C and/or
- protein S deficiency.
- </p>
- <p>
- J Clin Lab Anal 1998;12(3):145-9. A proposal for standardizing urine collections for bone resorption markers
- measurement. Zaninotto M, Bernardi D, Ujka F, Bonato P, Plebani M. The findings suggest that nocturnal
- collection and first morning void samples provide the most reliable data on the rate of bone degradation,
- possibly showing bone loss not only in osteopenic patients but also in women with a low T-score.
- </p>
-
- <p>
- Am J Physiol Renal Physiol 2001 Aug;281(2):F366-73. Increased CO(2) stimulates K/Rb reabsorption mediated by
- H-K-ATPase in CCD of potassium-restricted rabbit. Zhou X, Nakamura S, Xia SL, Wingo CS.
- </p>
- <p>
- Sci Total Environ 1981 Apr;18:35-45 Water hardness and mortality in the Netherlands. Zielhuis RL, Haring BJ.
- The hypothesis that the Ca and Mg deficiency in areas with soft drinking water increases the risk of I.H.D.
- death rate was supported by the finding that food loses more Ca and Mg when it is cooked in soft water as
- compared to cooking in hard water. However, investigation of a group of 17 municipalities of which mortality
- and water quality data are known for three periods, 1958-1962, 1965-1970 and 1971-1977, showed that the
- inverse statistical relation between I.H.D. Mortality and water hardness still existed but with decreasing
- significance of correlation coefficients.
- </p>
- <p>
- J Clin Endocrinol Metab 1980 Dec;51(6):1274-8. Serotonin stimulates adenosine 3',5'-monophosphate
- accumulation in parathyroid adenoma. Zimmerman D, Abboud HE, George LE, Edis AJ, Dousa TP. Since cAMP acts
- as a mediator of parathyroid hormone (PTH) release, our results suggest that serotonin could be one of the
- factors regulating PTH secretion and/or contributing to PTH hypersecretion in various forms of primary
- hyperparathyroidism.
- </p>
- <p>
- Cas Lek Cesk 1997 Jul 30;136(15):459-63. <strong>
- [New drugs with positive effects on bones]
- </strong>
-
- [Article in Czech] Zofkova I, Kanceva RL. Magnesium influences bone in different ways. <strong>It activates
- osteoblasts, increases bone mineralization, and enhances the sensitivity of target tissues (incl. bone)
- to PTH and 1,25(OH)2 vitamin D3,</strong> Under certain conditions however, magnesium can stimulate bone
- resorption. A more potent factor than magnesium is stroncium, which not only activates osteoblats but
- decreases the number of osteoclasts, thus abolishing bone resorption and enhancing formation. <strong>
- Bicarbonates are also favourable for bone. NaHCO3 together with potassium citrate stimulates osteoblasts
- and enhances bone mineralisation.</strong>
-
- © Ray Peat Ph.D. 2009. All Rights Reserved. www.RayPeat.com
- </p>
- </body>
- </html>
|