• Biomedical Science Letters
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• v.9 no.1
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• pp.15-19
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• 2003

Parathyroid hormone has clearly emerged as the most promising new anabolic treatment for osteoporosis by increasing the activation of osteoblast. It is known that chlorella increases both bone mineral density (BMD) and the rate of bone formation. The purpose of the present study was to determine whether the chlorella dietary supplementation could effect the thyroid or parathyroid hormones associated with increased BMD and bone formation. Twenty-two postmenopausal woman were treated for four month with 4 gm of chlorella dietary supplementation per day, then assessed serum calcium,25 OH vitamin D$_3$, thyroid hormone and parathyroid hormone before and after treatment. The mean 25 OH vitamin D$_3$ and parathyroid hormone were shown to marked increases by 193% and 265% respectively, in contrast to decreases by 9.4%, 37%, 33% and 14% in serum calcium, triiodo-thyroxine, free thyroxine and thyroxine stimulation hormone. In conclusion, treatment of postmenopausal women with chlorella dietary supplementation resulted in an increase in BMD and bone formation through enhancement of parathyroid hormone and 25 OH vitamin D$_3$, and a decrease in thyroid hormones.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.5
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• pp.261-267
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• 2002

The aim of the present study was to investigate the interaction of $estradiol-17{\beta}-bovine$ serum albumin $(E_2-BSA)$ and calcitropic hormones, such as parathyroid hormone, calcitonin, and vitamin D, in regulation of $Ca^{2+}$ uptake in primary cultured renal proximal tubule cells. Statistically significant increase in $Ca^{2+}$ uptake was found from 2 hours after $(E_2-BSA)\;(10^{-9}\;M)$ treatment, while $estradiol-17{\beta}\;(10^{-9}\;M)$ did not affect. Treatment of the cells with $(E_2-BSA)\;(10^{-9}\;M)$ together with parathyroid hormone (PTH) $(10^{-8}\;M),$ vitamin D $(10^{-8}\;M),$ or calcitonin $(10^{-8}\;M)$ significantly stimulated $Ca^{2+}$ uptake by 32.50%, 29.30%, or 27.75%, respectively, compared with the control. However, calcitropic hormones did not exhibit any synergistic effect on the E2-BSA-induced stimulation. $E_2-BSA$ significantly increased cAMP generation and PKC activity. The stimulatory effect of cotreatment of $E_2-BSA$ and PTH or vitamin D was blocked by SQ22536 (an adenylate cyclase inhibitor) and staurosporine (a PKC inhibitor), but the effect of cotreatment of $E_2-BSA$ and calcitonin was not blocked. Furthermore, 8-Br-cAMP and TPA (an artificial PKC promoter) increased $Ca^{2+}$ uptake by 25.51% and 16.47%, respectively, compared with the control. In conclusion, $E_2-BSA$ combined with calcitropic hormones regulated $Ca^{2+}$ uptake partially via cAMP and PKC-dependent mechanisms in renal proximal tubule cells.

• Proceedings of the Korean Magnetic Resonance Society Conference
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• 2000.01a
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• pp.28-28
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• 2000

• Journal of Nutrition and Health
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• v.29 no.9
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• pp.943-949
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• 1996

Bone mineral density depends largely on the status of dietary minerals such as Ca, P, Mg, and F and proteins, physical activities, parathyroid hormone(PTH), calcitonin(CT), and vitamin D. The decrease of bone density often results in bone fractures and osteoporosis which is prevalent among postmenopausal women. This study was intended to examine the role of parathyroid hormone, calcitonin and cholecaliferol in bone density of mice that were fed different dual photon energy beams. We have measured three major parts of the bone : whole body, head and femur. The results are summarized as follows : 1) Bone mineral density (BMD) was more increased by feeding high Ca diet compared to that of the low Ca diet. 2) Both PTH and Vit D3 enhanced BMD in all of the different Ca levels. 3) When the dietary Ca was deequate CT showed a synergistic effect with PTH in boosting bone density, while CT+Vit D3 showed a negative effect. 4) CT tended to inhibit the effect of increasing bone density by PTH and Vit D3 in medium and low Ca groups. 5) The effect of increasing bone density by PTH in the head of mouse increased when dietary Ca was lower : The increment of bone density by PTH in high, medium, and low Ca was 3%, 8%, 19%, respectively. 6) Femur bone density was affected significantly by dietary Ca levels than hormones. The above observations indicate that bone mineral density can be improved by high dietary Ca and hormone injections including PTH, CT and cholecalciferol, and thus proper dietary and hormonal treatment may be used in preventing bone fractures and osteoporosis.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.80-86
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• 1996

Parathyroid hormone(PTH) is known to stimulate bone resorption and to inhibit bone collagen synthesis. In contrast, as the evidence of stimulation of bone formation by PTH has recently been observed, the study on the role of PTH involved in osteoporosis draws remarkable attention. This study has dealt with the role of alkaline phoshatase(AP), a marker enzyme for bone formation and osteoblast action, Animals(BALS/cmice) were divided into three dietary groups(high and medium Ca and Ca-free) and hormones including PTH, calcitonin(CT), cholecalciferol(citamin D) were i.p. injected. AP in the serum and liver was measured using Sigma 221 alkaline buffer solutions containing 9mM of p-nitrophenyl phoshate. Enzume was reacted at 37$^{\circ}C$ for 10 minutes and the reaction was stopped by 1.8ml of 0.1N NaOH and measured at 410nm. We found that serum and liver AP activity was increased by low dietary Ac. Compared to the control, and serum Ap activity was enhanced by PTH and vitamin D regardless of the dietary Ca. On the other hand, liver AP activity was inhibited by OTH and vitamin D at all levels of dietary Ca. CT inhibited the action of PTH and vitamin D in the serum. But, the inhibition of PTH and vitamin D action by CT was not observed in the liver, unlike in the case of serum.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.677-684
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• 1999

This study has dealt the effect of Ca regulating hormones and dietary Ca levels on Ca metabolism. Animals(BALB/c mice) were divided into three dietary groups(high and medium Ca and Ca free) and hormones including parathyroid hormone(PTH), calcitonin(CT), cholecalciferol(Vit D) were i.p. injected. After feeding experimental diets for five weeks, mice were anaethetized and sacrificed by heart puncture. We found that femur growth of mouse was slightly increased by high dietary Ca without showing statistical significance comparing to low dietary Ca group. The combination of PTH and CT showed the same effect when dietary Ca was high. At the same time, total mineral retention in bone was most affected by dietary Ca. In general, high Ca diet elevated Ca level in the serum. When dietary Ca was low, PTH stimulated Ca release from the bone into the serum, which was shown to be inhibited by CT treatment. Comparing to the control, PTH, Vit D and CT together tended to inhibit serum Ca level at high and medium dietary Ca. PTH and Vit D inhibited Ca reserve in the liver at all dietary levels of Ca. Both PTH and Vit D stimulated bone Ca retention when dietary Ca was low, but this effect was reversed when dietary Ca was high. When PTH, Vit D and CT were administered together, bone Ca level was greatly enhanced at low dietary Ca than at high dietary Ca, which suggests that these hormonal cooperation is needed for proper bone density maintenance especially when dietary minerals are not sufficient.

• Clinical and Experimental Reproductive Medicine
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• v.18 no.2
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• pp.197-199
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• 1991

The role of estrogen in calcium metabolism has not been well documented. To further investigate the effects of endogenous estrogen on the calcium regulating hormones in women, we correlated the changes of estrogen level with those of calcium regulating hormones during ovulation induction in 12 hypogonadal and 8 normally menstruating women. During ovulation induction, the serum leveles of estradiol rose from 40.0 to 831.0pg/ml. There were no significant changes in the serum leveles of total calcium, inorganic phosphorus, parathyroid hormone, calcitonin. However, 1, $25-(OH)_2D_3$ rose significantly from 31.0 to 47.2pg.ml as the endogenous $E_2$ increaed (p<0.005).

• Journal of Nutrition and Health
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• v.40 no.4
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• pp.320-326
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• 2007

An important related question is whether arginine has influence bone metabolism. The effect of arginine supplements on bone markers and related hormones were studied in young female Sprague-Dawley rats fed either an arginine supplemented diet or control diet. Twenty four rats (body weight 83${\pm}$5 g) were randomly assigned to one of two groups, consuming casein or casein with supplemented arginine diet. All rats were fed on experimental diet and deionized water ad libitum for 9 weeks. Bone formation was measured by serum osteocalcin and alkaline phosphatase (ALP) concentrations. And bone resorption rate was measured by deoxypyridinoline (DPD) crosslinks immunoassay and corrected for creatinine. Serum osteocalcin, growth hormone, estrogen, insulin-like growth factor-1 (IGF-1), parathyroid hormone (PTH) and calcitonin were analyzed using radioimmunoassay kits. The weight gain and mean food intake were not affected regardless of diets. The rats fed arginine-supplemented diet had not significantly different in ALP, osteocalcin, crosslinks value, PTH, estradiol, and IGF-1 compared to those fed casein diet group. The arginine-supplemented group had significantly higher growth hormone and calcitonin than casein group. This study suggests that arginine is beneficial for bone formation in growing female rats. Therefore exposure to diet which rich in arginine early in life may have benefits for bone formation and osteoporosis prevention.

• Journal of Oral Medicine and Pain
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• v.25 no.1
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• pp.53-62
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• 2000

Bone marrow culture systems are widely used to differentiate osteoclast-like cells in vitro using several osteotropic hormones. In this study, we isolated and cultured the mouse bone marrow cells with or without some osteotropic hormones such as parathyroid hormone(PTH), prostaglandin $E_2(PGE_2)$ and $l,25(OH)_2-vitamin$ $D_3$(Vit. $D_3$). We confirmed the formation of osteoclast-like cells morphologically and functionally by the expression of tartrate-resistant acid phosphatase(TRAP) and by their capability to resorb dentin slices. We also studied the effects of transforming growth $factor-{\beta}(TGF-{\beta})$ and epidermal growth factor(EGF) on the Vit. $D_3-induced$ osteoclast-like cell formation. In control, a few multinucleated cells were formed whereas PTH and $PGE_2$ increased the number of multinucleated cells. PTH, $PGE_2$ and Vit. $D_3$ induced the formation of TRAP-positive multinucleated cells. After culture of mouse bone marrow cells on the dentin slices with or without osteotropic hormones, giant cells with diverse morphology were found on the dentin slices under the scanning electronmicroscopy. After removing the attached cells, resorption pits were identified on the dentin slices, and the shape of resorption pits was variable. EGF increased the osteoclast-like cell formation induced by Vit. $D_3$, however, $TGF-{\beta}$ showed biphasic effect, which at low concentration, increased and at high concentration, decreased the osteoclast-like cell formation induced by Vit. $D_3$.

• Journal of Oral Medicine and Pain
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• v.49 no.2
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• pp.40-42
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• 2024

Hyperparathyroidism (HPT) is a significant condition marked by the overproduction of parathyroid hormones, affecting both systemic health and orofacial regions. Predominantly, secondary HPT associated with chronic kidney disease (CKD) is critical because of its link to widespread conditions such as diabetes and hypertension. This short article highlights the vital role of dental professionals in identifying HPT through panoramic radiography, which can reveal critical orofacial signs such as brown tumors, altered dental development, and specific bone changes. With the CKD prevalence expected to increase alongside an aging population, the importance of early detection of HPT and its manifestations in dental settings cannot be overstated. Dental practitioners play a crucial role in the early detection of HPT, emphasizing the importance of being knowledgeable about its orofacial manifestations.