• Journal of Veterinary Science
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• 제24권5호
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• pp.69.1-69.11
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• 2023

Background: Kalkitoxin (KT) is an active lipopeptide isolated from the cyanobacterium Lyngbya majuscula found in the bed of the coral reef. Although KT suppresses cell division and inflammation, KT's mechanism of action in vascular smooth muscle cells (VSMCs) is unidentified. Therefore, our main aim was to investigate the impact of KT on vascular calcification for the treatment of cardiovascular disease. Objectives: Using diverse calcification media, we studied the effect of KT on VSMC calcification and the underlying mechanism of this effect. Methods: VSMC was isolated from the 6 weeks ICR mice. Then VSMCs were treated with different concentrations of KT to check the cell viability. Alizarin red and von Kossa staining were carried out to examine the calcium deposition on VSMC. Thoracic aorta of 6 weeks mice were taken and treated with different concentrations of KT, and H and E staining was performed. Real-time polymerase chain reaction and western blot were performed to examine KT's effect on VSMC mineralization. Calcium deposition on VSMC was examined with a calcium deposition quantification kit. Results: Calcium deposition, Alizarin red, and von Kossa staining revealed that KT reduced inorganic phosphate-induced calcification phenotypes. KT also reduced Ca⁺⁺-induced calcification by inhibiting genes that regulate osteoblast differentiation, such as runtrelated transcription factor 2 (RUNX-2), SMAD family member 4, osterix, collagen 1α, and osteopontin. Also, KT repressed Ca²⁺-induced bone morphogenetic protein 2, RUNX-2, collagen 1α, osteoprotegerin, and smooth muscle actin protein expression. Likewise, Alizarin red and von Kossa staining showed that KT markedly decreased the calcification of ex vivo ring formation in the mouse thoracic aorta. Conclusions: This experiment demonstrated that KT decreases vascular calcification and may be developed as a new therapeutic treatment for vascular calcification and arteriosclerosis.

• Preventive Nutrition and Food Science
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• 제18권2호
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• pp.92-97
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• 2013

The calcification of vascular smooth muscle cells (VSMCs) is considered one of the major contributors for vascular disease. Phosphate is known as the inducer for VSMC calcification. In this study, we assessed whether phosphate affected cell viability and fetuin-A, a calcification inhibitor protein, both which are related to VSMC calcification. Also, VSMC viability by zinc level was assessed. The results showed that phosphate increased Ca and P deposition in VSMCs (A7r5 cell line, rat aorta origin). This phosphate-induced Ca and P deposition was consistent with the decreased A7r5 cell viability (P<0.05), which implies phosphate-induced calcification in A7r5 cells might be due to the decreased VSMC cell viability. As phosphate increased, the protein expression of fetuin-A protein was up-regulated. A7r5 cell viability decreased as the addition of cellular zinc level was decreased (P<0.05). The results suggested that zinc deficiency causes the decreased cell viability and it would be the future study to clarify how zinc does act for VSMC cell viability. The results suggest that the decreased VSMC viability by high P or low Zn in VSMCs may be the risk factor for vascular disease.

• International Journal of Oral Biology
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• 제33권1호
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• pp.33-43
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• 2008

In the process of bone remodeling, mineral phase of bone is dissolved by osteoclasts, resulting in elevation of calcium concentration in micro-environment. This study was performed to explore the effect of high extracellular calcium ($Ca{^{2+}}_e$) on mineralized nodule formation and on the expression of progressive ankylosis (Ank), plasma cell membrane glycoprotein-1 (PC-1) and osteopontin by primary cultured mouse calvarial cells. Osteoblastic differentiation and mineralized nodule formation was induced by culture of mouse calvarial cells in osteoblast differentiation medium containing ascorbic acid and ${\beta}$-glycerophosphate. Although Ank, PC-1 and osteopontin are well known inhibitors of mineralization, expression of these genes were induced at the later stage of osteoblast differentiation during when expression of osteocalcin, a late marker gene of osteoblast differentiation, was induced and mineralization was actively progressing. High $Ca{^{2+}}_e$(10 mM) treatment highly enhanced mRNA expression of Ank, PC-1 and osteopontin in the late stage of osteoblast differentiation but not in the early stage. Inhibition of p44/42 MAPK activation but not that of protein kinase C suppressed high $Ca{^{2+}}_{e^-}$induced expression of Ank, PC-1 and osteopontin. When high $Ca{^{2+}}_e$(5 mM or 10 mM) was present in culture medium during when mineral deposition was actively progressing, matrix calcifiation was significantly increased by high $Ca{^{2+}}_e$. This stimulatory effect was abolished by pyrophosphate (5 mM) or levamisole (0.1-0.5 mM), an alkaline phosphatase inhibitor. In addition, probenecid (2mM), an inhibitor of Ank, suppressed matrix calcification in both control and high $Ca{^{2+}}_{e^-}$treated group, suggesting the possible role of Ank in matrix calcification by osteoblasts. Taken together, these results showed that high $Ca{^{2+}}_e$ stimulates expression of Ank, PC-1 and osteopontin as well as matrix calcification in late differentiation stage of osteoblasts and that p44/42 MAPK activation is involved in high $Ca{^{2+}}_{e^-}$induced expression of Ank, PC-1 and osteopontin.

• 한국임상약학회지
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• 제24권3호
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• pp.199-205
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• 2014

Objectives: Current studies are debating on the association of vascular calcification and the benefit of treatment to lower serum phosphorus level in patients with chronic kidney disease. The aim of this study was to evaluate the association of mortality and risk of vascular calcification in patients with CKD who were taking phosphate binders. Methods: This study was conducted through retrospective medical chart review for 420 patients aged 18 years and older who were admitted for chronic kidney disease. Results: Vascular calcification was not statistically significantly associated with increased mortality in patients with CKD [16.7% vs. 19.2%; 95% CI; 0.388 to 1.818 (p=0.656)]. Intervention of calcium-based phosphate binders was not significantly associated with vascular calcification in patients with CKD [9.1% vs. 12.5%; 95% CI; 0.364 to 1.358 (p=0.292)]. Ca x P product ${\geq}55mg^2/dL^2$ was not significantly associated with increased 1 year mortality in patients with CKD [25.4% vs. 17.5%; 95% CI; 0.851 to 3.013 (p=0.142)]. Intervention of sevelamer was significantly associated with reduced 1 year mortality in patients with CKD than that of patients who did not take sevelamer [6.3% vs. 25.3%; 95% CI; 0.044 to 0.880 (p=0.020)]. Conclusion: There was not a statistically significant association between vascular calcification and phosphate binder's use. But phosphate binder use was significantly associated with decreased mortality in patients with CKD.

• 동의생리병리학회지
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• 제22권1호
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• pp.142-147
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• 2008

This study was purpose to investigate that Gucheokbogol-tang(GBT), mainly used in osteoporosis, has possible regulatory effect on bone regeneration by operating in proliferation and calcification of osteoblast. So that, their cytotoxicity and proliferation was investigated with MTT by ELISA, and morphological change was observed by optical microscope and electron microscope. And activation of alkaline phosphates(ALP) which is secreted in early stage of bone formation was measured, and accumulation of $Ca^{2+}$ in the process of calcification was investigated by alizaline red S assay(ARS). The results were as follows: The MG-63 cell, originated from human cell was activated in $10^{-5}$ treated group, and the level of ALP was also increased in the treated group, highest on the third day. And from the outcome of ARS assay of calcification process in the Gucheokbogol-tang(GBT) treated group for 21days. These results suggested that Gucheokbogol-tang(GBT) is effective in proliferation and calcification of osteoblast.

• Childhood Kidney Diseases
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• 제12권2호
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• pp.239-244
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• 2008

말기 신부전으로 투석을 받는 환자의 결막과 각막에 골 외 석회 침착이 발생할 수 있다. 결막과 각막의 석회 침착은 대부분 장기간 혈액 투석을 받은 성인에서 보고되고 있으며, 신대체 요법의 기간, 높은 혈청 Ca$\times$P 등과 연관되는 것으로 알려져 있다. 저자들은 31개월째 복막 투석을 받고 있는 10세 여아에서 발생한 심한 결막과 각막의 석회 침착이 각막 주변부 상피세포 제거와 EDTA 투여로 호전된 경험을 하였기에 보고하는 바이다.

• 대한치과의사협회지
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• 제12권4호
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• pp.269-273
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• 1974

This present investigation was concerned with the content of ash, Mg, Ca, K and N'a of bone, cartilage, incisor teeth and molar teeth in rats of different weights. The results obtained were summarized as follows. 1. Cartilage is the most adequate model for the study in vivo of mechanisms concerned with normal calcification. 2. The percentage of inorganic material in cartilage rose from approx 13% of the dry weight in 5g rat to 46% in the tissue from rats weighing 134g 3. There was no marked change in the content of ash, Ca, Mg, K and Na after eruptions due to the increasing weight.

• Journal of Periodontal and Implant Science
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• 제38권sup2호
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• pp.273-298
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• 2008

Purpose: The aim of this review is to introduce a novel bone-graft material for hard-tissue regeneration based on the calcium phosphate glass(CPG). Materials and Methods: CPG was synthesized by melting and subsequent quenching process in the system of CaO-$CaF_2-P_2O_5$-MgO-ZnO having a much lower Ca/P ratio than that of conventional calcium phosphates such as HA or TCP. The biodegradability and bioactivity were performed. Effects on the proliferation, calcification and mineralization of osteoblast-like cells were examined in vitro. Influence in new bone and cementum formations was investigated in vivo using calvarial defects of Sprague-Dawley rats as well as 1-wall intrabony defect of beagle dogs. The application to the tissue-engineered macroporous scaffold and in vitro and in vivo tests was explored. Results: The extent of dissolution decreased with increasing Ca/P ratio. Exposure to either simulated body fluid or fetal bovine serum caused precipitation on the surface. The calcification and mineralization of osteoblast-like cells were enhanced by CPG. CPG promoted new bone and cementum formation in the calvarial defect of Sprague-Dawley rats after 8 weeks. The macroporous scaffolds can be fabricated with $500{\sim}800{\mu}m$ of pore size and a three-dimensionally interconnected open pore system. The stem cells were seeded continuously proliferated in CPG scaffold. Extracellular matrix and the osteocalcin were observed at the $2^{nd}$ days and $4^{th}$ week. A significant difference in new bone and cementum formations was observed in vivo (p<0.05). Conclusion: The novel calcium phosphate glass may play an integral role as potential biomaterial for regeneration of new bone and cementum.

• 대한치과보철학회지
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• 제33권2호
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• pp.317-334
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• 1995

The purpose of this study was to compare the bone formation, maturation around HA-and titaniumcoated dental implants in dog. 5 hydroxyapatite coated IMZ implants and 5 titanium coated IMZ implants were placed into the previously extracted site in the mandible of 5 adults dogs. All dogs were injected intravenously Tetracycline, Alizalin red S, and Calcein for bone fluorescent labelling, After the experimental period of 16weeks, the dogs were sacrificed and tissue samples around the implants were obtained. Microscopic observations(ligth, polariged and fluorescence microscope), morphometric analysis, line profile with EPMA, and quantitative analysis for Ca,P, and Ti were performed. The results were as follows ; 1. Bone maturations around the implants were relatively lower than those of natural teeth. No significant differences in bone maturation and remodeling patterns were observed between the two implants groups. 2. Calcification of bone surrounding the implants was initiated in 8-11 weeks for HA-coated implants, while it took 11 weeks or more for Ti-coated implants. 3. Bone-to-implants contact ratio of 82.63% was recorded for HA-coated group and 72.25% for titanium coated group, with no significant difference between the two groups. 4. Bone around the implants exhibited reduced quantity of Ca and P in the $100{\mu}m$ region relative to natural teeth, while the rest of the regions showed no statistical differences. No significant differences were found between the two implant groups. 5. There was a separation of HA layer from the implant core and subsequent infiltration of inflammatory cells into the resulting space in the HA-coated implants, and evidences of phagocytosis of HA particles by macrophages. Bone calcification was more rapid around HA-coated implants compared to titanium-coated implants, but HA coated implants did not show any significant differences either in the degree of calcification or the bone-to-implant contact ratio over Ti coated implants. HA coated implants may have complications associated with HA absorption and separation of HA layer from the implant core.

• Journal of Nutrition and Health
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• 제44권2호
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• pp.101-111
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• 2011

It is controversial whether low calcium intake, commonly associated with osteoporosis, results in calcium accumulation in soft tissues. This study was conducted to investigate the effects of low calcium (Ca) and oxalate (ox) intake on soft-tissue Ca deposits and bone metabolism in ovariectomized (ovx) rats. Eight week old female Sprague-Dawley rats were ovariectomized and divided into four groups. The rats were fed experimental diets containing low (0.1%, w/w) or normal (0.5%, w/w) Ca with or without sodium oxalate (1%, w/w); Sham/NCa, Ovx/NCa, Ovx/LCa, Ovx/NCa-ox, Ovx/LCa-ox for 6 weeks. All ovx rats showed a remarkable increase in body and tissue weight, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, blood urea nitrogen, alkaline phosphatase, and decreases in weight, ash, and Ca contents, as well as bone breaking force compared to those in sham rats. Serum Ca concentration was not significantly affected by dietary Ca levels or ox intake. Kidney Ca, ox acid content, and microscopic Ca deposition increased remarkably in the Ovx/LCa-ox group compared to those in the other groups. Ca content in the spleen and aorta also increased significantly, but the weight contents, Ca, bone breaking force, and Ca and oxalic acid in feces decreased significantly in the Ovx/LCa-ox group. Serum parathyroid hormone levels were not significantly different among the groups. These results indicate that low Ca intake decreased bone mineral content and increased Ca deposits in soft tissues, which was aggravated by ox intake in ovx rats. Thus, high ox intake may result in a kidney disorder in patients with osteoporosis who eat a low Ca diet.