• Animal cells and systems
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• v.13 no.4
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• pp.363-370
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• 2009

Since vitamin $D_3$ is an important regulator of osteoblastic differentiation, a presently-established vitamin $D_3$-entrapped calcium phosphate film (VCPF) was evaluated for hard tissue engineering. The entrapped vitamin $D_3$ more rapidly induced bone nodule formation. To characterize the cellular events leading to regulations including faster differentiation, signal transduction pathways were investigated in osteoblastic MG63 cells at a molecular level. Major signaling pathways for MG63 cell proliferation including phosphatidylinositol-3-kinase, extracellular signal-regulated kinase, c-Jun N-terminal kinase and focal adhesion kinase pathways were markedly down-regulated when cells were cultured on calcium phosphate film (CPF) and VCPF. This agreed with our earlier observations of the immediate delay in proliferation of MG63 cells upon culture on CPF and VCPF. On the other hand, the p38 mitogen-activated protein kinase (p38 MAPK) and protein kinase A (PKA) pathways were significantly up-regulated on both CPF and VCPF. CPF alone could simulate differential behaviors of MG63 cells even in the absence of osteogenic stimulation and entrapment of vitamin $D_3$ within CPF further amplified the signal pathways, resulting in continued promotion of MG63 cell differentiation. Interplay of p38 MAPK and PKA signaling pathways likely is a significant event for the promotion of differentiation and mineralization of MG63 cells.

• International Journal of Oral Biology
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• v.30 no.1
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• pp.23-30
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• 2005

Bone remodeling is a process controlled by the action of two major bone cells; the bone forming osteoblast and the bone resorbing osteoclast. In the process of osteoclastogenesis, stromal cells and osteoblast produce RANKL, OPG, and M-CSF, which in turn regulate the osteoclastogenesis. During the bone resorption by activated osteoclasts, extracellular $Ca^{2+}/{PO_4}^{2-}$ concentration and degraded organic materials goes up, providing the hypertonic microenvironment. In this study, we tested the effects of hypertonicity due to the degraded organic materials on osteoclastogenesis in co-culture system. It was examined the cellular response of osteoblastic cell in terms of osteoclastogenesis by applying the sucrose, and mannitol, as a substitute of degraded organic materials to co-culture system. Apart from the sucrose, mannitol, and NaCl was tested to be compared to the effect of organic osmotic particles. The addition of sucrose and mannitol (25, 50, 100, 150, or 200 mM) to co-culture medium inhibited the number of tartrate-resistant acid phosphatase (TRAP) positive multinucleated cells induced by 10 nM $1{\alpha},25(OH)_2vitaminD_3$ ($1{\alpha},25(OH)_2D_3$). However, NaCl did exert harmful effect upon the cells in this co-culture system, which is attributed to DNA damage in high concentration of NaCl. To further investigate the mechanism by which hypertonicity inhibits $1{\alpha},25(OH)_2D_3$-induced osteoclastogenesis, the mRNA expressions of receptor activator of nuclear factor (NF)-kB ligand (RANKL) and osteoprotegerin (OPG) were monitored by RT-PCR. In the presence of sucrose (50 mM), RANKL mRNA expression was decreased in a dose-dependent manner, while the change in OPG and M-CSF mRNA were not occurred in significantly. The RANKL mRNA expression was inhibited for 48 hours in the presence of sucrose (50 mM), but such a decrement recovered after 72 hours. However, there were no considerable changes in the expression of OPG and M-CSF mRNA. Conclusively, these findings strongly suggest that hypertonic stress down-regulates $1{\alpha},25(OH)_2D_3$-induced osteoclastogenesis via RANKL signal pathway in osteoblastic cell, and may playa pivotal role as a regulator that modulates osteoclastogenesis.

• Journal of Nutrition and Health
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• v.51 no.4
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• pp.287-294
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• 2018

Purpose: This study was conducted to evaluate the association between serum 25-hydroxyvitamin D (25(OH)D) levels and dental caries experience in Korean adolescents based on the 2010 ~ 2014 Korean National Health and Nutrition Examination Surveys. Methods: The study subjects were 2,655 Korean adolescents aged 10 to 18 years. Subjects were classified into four groups according to their serum 25(OH)D levels. We used logistic regression to evaluate the relationship between vitamin D and for dental caries experience after adjusting for age, household income level, recipient of basic livelihood, tooth brushing and visiting dental clinics. Result: Multiple logistic regression analysis showed that serum 25(OH)D insufficiency (20 ng/mL ${\leq}25(OH)D$ < 30 ng/mL) was associated with increased odd ratios (ORs) for dental caries experience in boys (OR = 2.577, 95% CI = 1.013-6.557), compared with serum 25(OH)D sufficiency (25(OH)D ${\geq}30ng/mL$). Conclusion: The serum 25(OH)D levels were found to be related to risk of dental caries experience in Korean adolescent boys.

• The korean journal of orthodontics
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• v.27 no.2
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• pp.335-347
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• 1997

Vitamin D is known to exert its action by activating DNA and RBA within target cells to produce proteins and enzymes that can be used in bone resorption process. Particularly, the active form of vitmain D, 1,25-dihydroxycholecalciferol $[1,25-(OH)_2D_3]$, is considered to be one of the most potent stimulators of osteoclatic acitivity in vitro. The purpose of this study was to evaluate the effect of 1,25-Dihydroxyvitamin $D_3$ on the avtivity of periodotal ligament cells and, the experimental tooth movement. Human periodontal ligament cells were collected from the first premolar tooth extracted for the orthodontic treatment, and were incubated in the environment of $37^{\circ}C$, 5% $CO_2$ and 95% humidity. Microtitration(MIT) assay was done at 10, 25, 50 and 100ng/ml of 1,25-Dihydroxyvitamin $D_3$. 21 Sprague-Daft rats were divided into a control gmup(3), and experimental groups(18) where 100g of force from helical spring was applied across the maxillary incisors 1,25-Dihydroxyvitamin $D_3$ was injected into periodontal ligament at the mesial or distal surface of maxillary incisors so that we can compare the control side and the experimental side. Expreimental groups were sac rifled at 12, 24, 36, 48, 72hours and 7 days after force application, respectively. And the obtained tissues were evaluated histologically. The observed results were as follows. 1. The activity of periodontal ligament cells in l0ng/ml or 25ng/ml of 1,25-Dihydroxyvitamin $D_3$ 1,25-Dihydroxyvitamin $D_3$ was not significantly different to the control at the cultivation of 1, 2 and 3 days. 2. The activity of periodontal ligament cells was significantly increased at 3 days in 50 ng/ml of 1,25-Dihydroxyvitamin $D_3$ and 2, 3 days in 100g/ml of 1,25-Dihydroxyvitamin $D_3$. 3. Up to 7 days after force application, there was no difference in osteoblastic activity, tearing of periodontal ligament and proliferation of capillary at tension side between 1,25-Dihydroxyvitamin $D_3$ injection side and the control side. 4. The osteoclastic activity and the resorption of alveolar bone was greater in 1,25-Dihydroxyvitamin $D_3$ injection side than the control side at 36 hours after force application.

• Journal of Animal Science and Technology
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• v.45 no.3
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• pp.455-462
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• 2003

A study was conducted to determine the effects of feeding a diet containing no Ca supplement (limestone) during the late finishing period on growth, marbling and serum 1,25-dihydroxy vitamin $D_3$ level in Korean native cattle. Twenty-four steers (20${\sim}$24 mo of age) were divided into two groups of 12 each: one group assigned to a control diet (concentrates containing 2.5% limestone) and the other to a diet containing no calcium supplement. They were allowed to have free access to diets (concentrates and orchard grass hay) and water during the entire feeding period (223 d). Serum $Ca^{2+}$, Ca and P concentrations were not influenced by diets, but serum 1,25-dihydroxy vitamin $D_3$ concentrations determined 2 or 6 mo after the beginning of feeding the experimental diets were higher (P<0.01) in steers fed the diet without Ca supplement than in those fed the control diet (78.3 vs 51.7 and 80.3 vs 51.1 pg/mL, respectively). Steers fed the diet without Ca supplement tended to have a higher intake of concentrates, but a lower intake of hay, compared to those fed the control diet. Average daily gain was higher (P<0.05) in steers fed the diet without Ca supplement than in those fed the control diet. Feeding the diet without Ca supplement remarkably (P<0.01) increased the marbling score (5.1 vs 2.2) and the muscle (M. longissimus dorsi) fat content (10.2 vs 6.7%) with a concomitant decrease in moisture content (67.6 vs 70.4%), compared to feeding the control diet. Ribeye area was increased (77.2 vs 82.8 $cm^2$) with the diet without Ca supplement, compared to the control diet (P<0.05). Meat color, pH and water-holding capacity in longissimus muscle were not different between the two groups. The Warner-Brazler Shear (WBS) force of the longissimus muscle was slightly (P=0.08) lower in steers fed the diet without Ca supplement than in steers fed the control diet (2.9 vs 3.2 kg/1.27-cm diameter core). Sensory evaluation showed that feeding the diet without Ca supplement slightly (P<0.05) improved tenderness (4.9 vs 4.5) and flavor (4.9 vs 4.6), compared to feeding the control diet, but juiciness was not affected by diets. Results showed that deletion of Ca supplement from finishing diets is beneficial, increasing growth and marbling partly through an increased energy intake and induced 1,25-dihydroxy vitamin $D_3$ synthesis that may increase intracellular $Ca^{2+}$ concentration and in turn fat synthesis.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3339-3344
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• 2015

Background: This case-control study aimed to determine if there were any associations between the two single nucleotide polymorphisms (SNPs) in Gc, rs7041 (Asp416Glu) and rs4588 (Thr420Lys) and 3 common cancers (breast, lung and colorectal) in Thai patients. Materials and Methods: Two hundred and eighty two colorectal, 101 breast and 113 lung cancer patients were recruited from one institute during 2011-2013. The controls were age-matched volunteers who had a negative history of index cancers. In addition, vitamin D levels were compared among different genotypes in the 2 SNPs. Results: The minor allele frequencies of rs7041 (G) and rs4588 (A) were 0.32 and 0.24, respectively. Under the dominant model, the study found significant associations between minor-allele genotypes of the SNP rs7041 (TG/GG) and lung cancer (odds ratio [OR] 1.78, 95% CI 1.05-3.03). When subgroup analysis was performed according to sex and age at diagnosis, the study found that the minor-allele genotypes of rs7041 (TG/GG) were significantly associated with colorectal cancer in patients whose age at diagnosis was more than 60 years (OR 1.67, 95%CI 1.06-2.61) and the minor-allele genotypes of rs4588 (CA/AA) were significantly associated with colorectal cancer in males aged 60 years or less (OR 2.34, 95%CI 1.25-4.37). When SNP combinations (rs7041-rs4588) were examined, the TT-CA combination had a significant protective association with lung cancer (OR 0.44, 95% CI 0.22-0.85). On evaluation of serum 25(OH)D levels in 205 individuals without cancer (males 144, females 61), the proportion of subjects with low serum vitamin D (< 20 ng/ml) in those harboring CA or AA genotypes of rs4588 (41.7%) was significantly higher than the CC genotype (15.5%, p-value < 0.01). Conclusions: Genetic polymorphisms in Gc were associated with lung and colorectal cancers in Thai patients. Lower serum 25(OH)D in minor variants of rs4588 may explain this association.

• Journal of Acupuncture Research
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• v.23 no.2
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• pp.103-111
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• 2006

Objectives : Deer antler Water Extract(DAE), prepared from the pilose antler of Cervus korean TEMMINCK var. mantchuricus Swinhoe (Nokyong), a traditional immuno-suppressive and immuno-activating Korean herbal-acupuncture, is thought to play an important role in human bone remodeling. Methods : To determine whether DAE can induce the differentiation of resting zone chondrocytes(RC) or not, confluent cell cultures were pretreated for 24, 36, 48, 72, and 120hrs with DAE. At the end of pretreatment, the media were replaced with new media containing $10^{-10}{\sim}10^{-8}M\;1,25-(OH)_2D_3$ and the cells incubated for an additional 24hrs. Results : This second treatment was chosen because prior studies had shown that only the more mature growth zone chondrocytes(GC) respond to this vitamin $D_3$ metabolite. The effect of DAE pretreatment on cell maturation was confirmed by measuring alkaline phosphatase (ALPase)-specific activity. Changes in matrix protein synthesis were examined by measuring collagen synthesis, as well as $^{35}SO_4$ incorporation into proteoglycans. When RC cells were pretreated for 120h with DAE, treatment with $1,25-(OH)_2D_3$ caused a dose-dependent increase in ALPase-specific activity and collagen synthesis, however, the proteoglycan production was not affected. RC cells pretreated with $1,25-(OH)_2D_3$ responded like RC cells that had not received any pretreatment. Conclusion : These results indicate that DAE directly regulates the maturation of RC chondrocytes into GC chondrocytes. Therefore it was indicated that DAE may play a significant role in regulating chondrocyte maturation during endochondral ossification.

• Childhood Kidney Diseases
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• v.7 no.2
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• pp.234-238
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• 2003

Fanconi syndrome is a generalized functional disorder of the proximal tubule of the kidney and is characterized by aminoaciduria, glycosuria, hyperphosphaturia, dehydration, rickets, and growth failure. Nephrocalcinosis and hypercalciuria are rare manifestations of Fanconi syndrome. There is no case report of Fanconi syndrome complicated with nephrocalcinosis and hypercalciuria in Korea. A 6-year-old boy presented with genu valgum and waddling gaits for about 3 years. There was no family history of renal disease and his physical examination was normal except for genu valgum and corrected cleft lip and palate. Laboratory investigations showed generalized aminoaciduria, glycosuria, hyperphosphaturia, hypercalciuria, and low-molecular weight proteinuria including ${\beta}$-microglobulin. Serum 25-OH vitamin $D_3$ was within the normal range, and $1,25-(OH)_2$ vitamin $D_3$ was elevated. Bilateral renal medullary hyperechogenicity was demonstrated by ultrasonography. Analysis of the CLCN5 gene revealed no mutation. Here we describe a boy with Fanconi syndrome complicated with nophrocalcinosis and discuss the differential diagnosis.

• Journal of Nutrition and Health
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• v.47 no.2
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• pp.89-98
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• 2014

Purpose: Association of low intake of calcium (Ca) and inadequate vitamin D (VD) status with higher prevalence rates of obesity has been reported. This study was conducted in order to investigate the effects of different levels of whey Ca and VD intake on lipid metabolism in growing rats. Methods: A total of 56 five-week-old male Sprague-Dawley rats were divided into seven groups and fed for five weeks. Ca groups were divided into three levels, low, normal, and high (0.25%, 0.5%, 1%). VD subgroups in the low and high Ca groups were divided into three levels, low, normal, and high (10 IU, 1,000 IU, and 5,000 IU). The effects of Ca and VD on each group were evaluated by two way ANOVA. Results: Significantly higher amounts of abdominal fat, visceral fat, and epididymal fat were observed in the Low-Ca groups than in the Normal-Ca and High-Ca groups. Serum leptin levels of Low-Ca groups were higher than those of Normal-Ca and High-Ca groups. The highest serum parathyroid hormone concentration was observed in the low Ca low VD group. The levels of serum 25(OH)D were significantly increased with increasing dietary VD levels. Significantly higher serum levels of triglycerides, total cholesterol, and HDL-cholesterol were observed in the low Ca groups than in the normal Ca and high Ca groups. Conclusion: These results indicate that low calcium intake increased serum lipid level and body fat amount.

• The Korean Journal of Food And Nutrition
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• v.6 no.3
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• pp.219-230
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• 1993

This research aims to study the changes In gastrointestinal function attributed to aging In human. The thresholds for recognition and detection of flavors became elevated and salivary gland acinar cells decreased in the old age. But most esophageal function remained relatively Intact. Although gastric emptying time has been slowed with aging, the total intestinal transit time did not differ. Atropic gastritis due to H. pylori in old man decreased secretion of acid and Intrinsic factor and absorbability of calcium and iron. Pancreatic secretion is droned in older persons. Prevalence of gallstones rised with age. Liver size and portal blood flow decreased significantly with age. Mucosal surface area has been reported to be slightly diminished in the aging man. Glucose transporters decreased and Insulin tolerance Increased. Absorption of aromatic amino acid is diminished with age. Dietary protein In that aging human increased fecal nitrogen excretion. Vitamin A tolerance increased. Vitamin D receptor concentration decreased and resistance to 1,25-(OH)2D3 action increased. Permeability of aging small Intestine Increased. Zinc balance dirt not differ Copper absorption appeared not to be significantly affected by age. Neurotensin secretion decreased thus slowed colonic peristaltic movements and Intestinal mucosal growth.