Taurine Increases Bone Density in Rats

Abstract

The effects of dietary taurine supplementation on bone mineral density in ovariectomized rats.

This study was performed to evaluate the effect of a diet rich in taurine (2.0 g/100 g) on bone metabolism in ovariectomized (OVX) rats. All rats were fed deionized water during the experimental period. Bone mineral density (BMD) and bone mineral content (BMC) of spine and femur were measured. Serum and urinary calcium and phosphorus content were determined. The levels serum osteocalcin and alkaline phosphatase (ALP) were used to assess bone formation. The rate of bone resorption was measured by the deoxypyridinoline (DPD) crosslink immunoassay and corrected for creatinine. Urinary Ca and P excretion, serum osteocalcin content, and the crosslink value were not significantly different between the Sham groups. The taurine supplemented, Sham group had higher spinal and femur BMC than those of the untreated control group, but the difference was not statistically significant. However, the taurine supplemented, Sham group had significantly higher spine and femur BMC per weight than those of the untreated control group. Within the OVX group, the taurine supplemented group had a lower crosslink value than the casein group. The taurine supplemented, OVX group had higher femur bone mineral content per weight than those of the control, OVX group, but the difference was not statistically significant. A study examining the long-term effect of taurine supplementation in humans is warranted.

Choi MJ, DiMarco NM
Adv. Exp. Med. Biol. 2009
PMID: 19239165

Review: Nutrients Involved in Maintaining Healthy Bone

Abstract

Update on nutrients involved in maintaining healthy bone.

Osteoporosis is a leading cause of morbidity and mortality in the elderly and influences quality of life, as well as life expectancy. Currently, there is a growing interest among the medical scientists in search of specific nutrients and/or bioactive compounds of natural origin for the prevention of disease and maintenance of bone health. Although calcium and vitamin D have been the primary focus of nutritional prevention of osteoporosis, a recent research has clarified the importance of several additional nutrients and food constituents. Based on this review of the literature, supplementation with vitamins B, C, K, and silicon could be recommended for proper maintenance of bone health, although further clinical studies are needed. The results of studies on long-chain polyunsaturated fatty acids, potassium, magnesium, copper, selenium, and strontium are not conclusive, although studies in vitro and in animal models are interesting and promising.

Rondanelli M, Opizzi A, Perna S, Faliva MA
Endocrinol Nutr Apr 2013
PMID: 23273614

Garlic Oil Prevents Bone Loss in Ovariectomized Rats

Abstract

Role of peritoneal macrophages and lymphocytes in the development of hypogonadal osteoporosis in an ovariectomized rat model: possible phytoestrogenic efficacy of oil extract of garlic to preserve skeletal health.

This study was to examine whether skeletal health deterioration in the hypogonadal situation is a consequence of an alteration in the functional status of peripheral mononuclear cells and its amelioration, if any, by an oil extract of garlic. The results suggest that hypogonadism-induced oxidative stress of peritoneal macrophages and lymphocytes could be reduced by supplementation with an oil extract of garlic. However, estrogen deficiency did not cause any significant change in DNA fragmentation of peritoneal macrophages. The hypogonadism-induced increase in the serum levels of IL-6 and TNF-alpha were significantly reduced by an oil extract of garlic. Further, such supplementation could revive the hypogonadism-induced decrease in serum estrogen titer and counter-balance the increase in bone turnover as determined by low bone tensile strength and alterations in bone related biochemical variables such as urinary calcium, hydroxyproline, calcium to creatinine ratio and serum tartrate resistant acid phosphatase activity (TRAP). The garlic oil supplemented partial recovery of the serum estrogen titer in hypogonadal rats was found to be persistently associated with reduced oxidative stress of peritoneal macrophages and lymphocytes, reduced serum interleukins and better preservation of bone mass. This study proposes that the hypogonadism-induced bone loss has a direct correlation with the functional status of lymphocytes and peritoneal macrophages, and garlic can prevent this.

Mukherjee M, Das AS, Das D, Mukherjee S…
Phytother Res Nov 2007
PMID: 17600860

Garlic Oil Prevents Bone Mineral Loss in Rats

Abstract

Role of oil extract of garlic (Allium sativum Linn.) on intestinal transference of calcium and its possible correlation with preservation of skeletal health in an ovariectomized rat model of osteoporosis.

The present study was undertaken to examine the effects of an oil extract of garlic on the in vivo intestinal transference of calcium, and also to verify its role in maintaining the bone mineral content and bone tensile strength in an ovariectomized rat model of osteoporosis. The results suggest that, in this experimental model, oil extract of garlic promotes intestinal transference of calcium by modulating the activities of both intestinal alkaline phosphatase and Ca(2+) activated ATPase. Also the observed low bone mineral content and low bone tensile strength in these rats were significantly restored by garlic oil supplementation. Further, garlic oil supplementation was able to revive partially the bilateral ovariectomy-induced decrease in the serum estrogen titer. The serum parathyroid hormone level, however, was found unaltered in these rats. The garlic oil supplemented partial recovery in serum estrogen titer in bilaterally ovariectomized rat was found to be persistently associated with enhanced calcium transference and better preservation of bone mineral content. The results of this study propose that the phytoestrogenic efficacy of an oil extract of garlic prevents ovarian hormone deficiency induced bone mineral loss possibly by promoting intestinal transference of calcium through the partial revival of the serum estrogen titer.

Mukherjee M, Das AS, Das D, Mukherjee S…
Phytother Res May 2006
PMID: 16619371

Garlic < Lovastatin < Estrogen Effective in suppressing Bone loss in Ovariectomized Rats

Abstract

Effects of garlic oil on postmenopausal osteoporosis using ovariectomized rats: comparison with the effects of lovastatin and 17beta-estradiol.

The purpose of this study was to examine the antiosteoporosis effects of garlic oil in an ovariectomized (Ovx) rat model of osteoporosis and to compare its efficacy with lovastatin (a synthetic hypocholesterolemic drug) and 17beta-estradiol (a potent antiosteoporotic agent). Animals were divided into five groups: sham-operated control, ovariectomized, ovariectomized supplemented with lovastatin, ovariectomized supplemented with garlic oil and ovariectomized supplemented with 17beta-estradiol. In our study, the development of a high rate of bone turnover and osteoporosis in the ovariectomized animals were confirmed by significant alterations of serum alkaline phosphatase activity, serum tartrate-resistant acid phosphatase activity, urinary excretion of calcium, phosphate, hydroxyproline and urinary calcium to creatinine ratio, when compared with the sham-operated control group. Supplementation of these animals with either garlic oil or lovastatin or 17beta-estradiol, in addition to their hypocholesterolemic effect, could counterbalance all these changes. The results revealed that all three compounds significantly protected the hypogonadal bone loss as reflected by higher bone densities and higher bone mineral contents than the ovariectomized group of animals. The results emphasize that, like 17beta-estradiol, the hypocholesterolemic compounds garlic oil and lovastatin are also effective in suppressing bone loss owing to estrogen deficiency and their efficacy in the order of lower to higher is garlic < lovastatin < 17beta-estradiol.

Mukherjee M, Das AS, Das D, Mukherjee S…
Phytother Res Jan 2006
PMID: 16397916

Garlic Oil Reverses Bone Loss in Ovariectomized Rats

Abstract

Prevention of bone loss by oil extract of garlic (Allium sativum Linn.) in an ovariectomized rat model of osteoporosis.

The effects of oil extract of garlic (Allium sativum Linn.) on different primary and secondary osteoporotic marker changes were tested in an ovariectomized rat model of osteoporosis. Experiments were performed on three different rat models: sham-operated control, ovariectomized and ovariectomized supplemented with garlic oil. In ovariectomized group, there has been a significant increase in different relative organ weights compared to sham-operated control, while the uterine weight was found to be decreased. Supplementation with oil extract of garlic could effectively reverse these changes. Also low bone densities that developed in the ovariectomized group were significantly recovered in the garlic oil supplemented group. In our study, the development of high rate of bone turnover and osteoporosis in the ovariectomized animals were confirmed by significant alteration of serum alkaline phosphatase activity, serum tartrate resistant acid phosphatase activity, urinary excretion of calcium, phosphate, hydroxyproline and urinary calcium to creatinine ratio, when compared with the sham-operated control group. Garlic oil extract supplementation, apart from its unique influence in lowering blood cholesterol, could also prevent ovariectomy-induced rise in all the above-mentioned marker changes. The results of this study emphasize that oil extract of garlic possibly has a positive role in suppressing ovariectomy-induced bone resorption.

Mukherjee M, Das AS, Mitra S, Mitra C
Phytother Res May 2004
PMID: 15173999

Ghrelin Stimulates Bone Formation in Rat Osteoblasts

Abstract

Ghrelin directly regulates bone formation.

To clarify the role of ghrelin in bone metabolism, we examined the effect of ghrelin in vitro and in vivo. Ghrelin and its receptor, GHS-R1a, were identified in osteoblasts, and ghrelin promoted both proliferation and differentiation. Furthermore, ghrelin increased BMD in rats. Our results show that ghrelin directly affects bone formation.
Ghrelin is a gut peptide involved in growth hormone (GH) secretion and energy homeostasis. Recently, it has been reported that the adipocyte-derived hormone leptin, which also regulates energy homeostasis and opposes ghrelin’s actions in energy homeostasis, plays a significant role in bone metabolism. This evidence implies that ghrelin may modulate bone metabolism; however, it has not been clarified. To study the role of ghrelin in skeletal integrity, we examined its effects on bone metabolism both in vitro and in vivo.
We measured the expression of ghrelin and growth hormone secretagogue receptor 1a (GHS-R1a) in rat osteoblasts using RT-PCR and immunohistochemistry (IHC). The effect of ghrelin on primary osteoblast-like cell proliferation was examined by recording changes in cell number and the level of DNA synthesis. Osteoblast differentiation markers (Runx2, collagen alpha1 type I [COLI], alkaline phosphatase [ALP], osteocalcin [OCN]) were analyzed using quantitative RT-PCR. We also examined calcium accumulation and ALP activity in osteoblast-like cells induced by ghrelin. Finally, to address the in vivo effects of ghrelin on bone metabolism, we examined the BMD of Sprague-Dawley (SD) rats and genetically GH-deficient, spontaneous dwarf rats (SDR).
Ghrelin and GHS-R1a were identified in osteoblast-like cells. Ghrelin significantly increased osteoblast-like cell numbers and DNA synthesis in a dose-dependent manner. The proliferative effects of ghrelin were suppressed by [D-Lys(3)]-GHRP-6, an antagonist of GHS-R1a, in a dose-dependent manner. Furthermore, ghrelin increased the expression of osteoblast differentiation markers, ALP activity, and calcium accumulation in the matrix. Finally, ghrelin definitely increased BMD of both SD rats and SDRs.
These observations show that ghrelin directly stimulates bone formation.

Fukushima N, Hanada R, Teranishi H, Fukue Y…
J. Bone Miner. Res. May 2005
PMID: 15824852

Phenytoin Inhibits Osteoblasts In Vitro and In Vivo; Low Doses Increase Osteoblasts In Vitro

Abstract

Long-term anticonvulsant therapy leads to low bone mineral density–evidence for direct drug effects of phenytoin and carbamazepine on human osteoblast-like cells.

Anticonvulsant therapy causes changes in calcium and bone metabolism and may lead to decreased bone mass with the risk of osteoporotic fractures. The two widely used antiepileptic drugs phenytoin and carbamazepine are recognized to have direct effects on bone cells. The aim of our study was to measure the influence of long-term treatment with antiepileptic drugs on bone mineral density (BMD) and to look on direct effects of carbamazepine and phenytoin on human osteoblast-like cells. BMD was measured by dual-energy X-ray absorptiometry. Markers of bone formation and bone resorption were determined in serum and urine. Data of 59 patients were compared to 55 age and sex matched controls. Direct effects of phenytoin and carbamazepine on human osteoblast-like cells were investigated in experimental studies. BMD in the lumbar spine region (L2 through L4) was significantly lower in the patient group as compared to controls (p < 0.0004). At femoral sites BMD was lower in patients, but this difference did not reach statistical significance. The decrease in BMD at both sites was dependent on the duration of therapy. Excretion of pyridinoline crosslinks was markedly increased in the patients. 25-hydroxy-vitamin D3 and 1,25-dihydroxy-vitamin D3 were significantly decreased in patients. Proliferation rate of human osteoblast-like cells was increased by phenytoin in low doses. Both, phenytoin and carbamazepine inhibited cell growth at concentrations equivalent to therapeutic doses for the treatment of epileptic diseases. Our clinical and experimental data indicate that long-term treatment with anticonvulsant drugs leads to a lower BMD. The experimentally observed decrease in bone cell proliferation might be clinically associated with impaired new bone formation. Beside alterations in calcium and vitamin D homeostasis leading to osteomalazia, direct effects of anticonvulsant drugs on bone cells may contribute to the damaging effects on the skeletal system.

Feldkamp J, Becker A, Witte OW, Scharff D…
Exp. Clin. Endocrinol. Diabetes 2000
PMID: 10768830

Phenytoin Inhibits Osteoclasts in Mice

Abstract

Diphenylhydantoin inhibits osteoclast differentiation and function through suppression of NFATc1 signaling.

Diphenylhydantoin (DPH) is widely used as an anticonvulsant drug. We examined the effects of DPH on osteoclast differentiation and function using in vivo and in vitro assay systems. Transgenic mice overexpressing a soluble form of RANKL (RANKL Tg) exhibited increased osteoclastic bone resorption. Injection of DPH into the subcutaneous tissue overlying calvaria of RANKL Tg mice suppressed the enhanced resorption in the calvaria. In co-cultures of mouse osteoblasts and bone marrow cells, DPH inhibited lipopolysaccharide (LPS)-induced osteoclast formation. DPH affected neither the mRNA expression of RANKL and osteoprotegerin nor the growth of mouse osteoblasts in culture. On the other hand, DPH inhibited the RANKL-induced formation of osteoclasts in cultures of mouse bone marrow-derived macrophages (BMMphis) and of human peripheral blood-derived CD14(+) cells. DPH concealed LPS-induced bone resorption in mouse calvarial organ cultures and inhibited the pit-forming activity of mouse osteoclasts cultured on dentine slices. DPH suppressed the RANKL-induced calcium oscillation and expression of nuclear factor of activated T cells c1 (NFATc1) and c-fos in BMMphis. Moreover, DPH inhibited the RANKL-induced nuclear localization and auto-amplification of NFATc1 in mature osteoclasts. Both BMMphis and osteoclasts expressed mRNA of a T-type calcium channel, Cav3.2, a target of DPH. Blocking the expression of Cav3.2 by short hairpin RNAs significantly suppressed RANKL-induced osteoclast differentiation. These results suggest that DPH inhibits osteoclast differentiation and function through suppression of NFATc1 signaling. The topical application of DPH may be a therapeutic treatment to prevent bone loss induced by local inflammation such as periodontitis.

Koide M, Kinugawa S, Ninomiya T, Mizoguchi T…
J. Bone Miner. Res. Aug 2009
PMID: 19292614

Phenytoin Stimulates Osteoblast Markers in Rat Cells

Abstract

Stimulatory effects of phenytoin on osteoblastic differentiation of fetal rat calvaria cells in culture.

Phenytoin (diphenylhydantoin, DPH), an anticonvulsant drug for epileptic patients, has several adverse effects, including calvarial thickening and coarsening of the facial features, which occur with chronic DPH therapy. While previous studies have demonstrated that DPH has an anabolic action on bone cells in vivo and in vitro, the basis of these effects is not fully understood. In this study, the effect of DPH on osteoblastic differentiation of fetal rat calvaria (RC) cells in culture was investigated by measuring bone nodule (BN) formation, cell growth, alkaline phosphatase (ALPase) activity, collagen synthesis, and expression of osteocalcin (OC) and osteopontin (OP) mRNAs. Continuous treatment of RC cells with DPH for 18 days dose-dependently increased the mineralized BN number by 1.2-1.7-fold at concentrations of 12.5-200 micromol/L DPH. Cell growth was not affected at the same concentrations of DPH. ALPase activity was stimulated by DPH (1.1-1.9-fold) dose-dependently and was maintained at higher levels in DPH-treated cells throughout the experimental period. DPH increased mineralized and unmineralized BN formations both in the presence and the absence of 10(-8) mol/L dexamethasone (Dex). Expression of OC and OP mRNAs was markedly augmented by DPH on days 12-24 and on days 12-18, respectively. While control mRNA levels of OC and OP increased with time, the increases in DPH-treated cells were greater than those of the controls and the stimulatory effects were dose-dependent. Type I collagen was also influenced by DPH; mRNA level was enhanced and the percentage of collagen synthesized was increased significantly, by 200 micromol/L DPH. When DPH was added in three different culture stages, days 1-6 (growth), days 7-12 (matrix development), and days 13-18 (mineralization), BN formation was influenced primarily on days 1-6 and secondarily on days 7-12, but not on days 13-18, suggesting that DPH increased BN formation by enhancing not only the proportion of osteoprogenitor cells in the early stage but also the proportion of functional osteoblasts in the middle stage within mixed-cell populations. Moreover, such increases were detected in conditions of both Dex(+) and Dex(-). These findings demonstrate that DPH stimulates osteoblast-associated markers such as BNs, ALPase, OC, OP, and type I collagen by continuously affecting the stages of growth and matrix development in RC cells, and suggests that the stimulatory effects by DPH may possibly be induced independent of those by Dex.

Ikedo D, Ohishi K, Yamauchi N, Kataoka M…
Bone Dec 1999
PMID: 10593409