Abstract. Matrix metalloproteinases (MMPs) play an important role in degeneration of the matrix associated with bone and cartilage. Regulation of osteoclast activity is essential in the treatment of bone disease, including osteoporosis and rheumatoid arthritis. Polyphenols in green tea, particularly epigallocatechin-3-gallate (EGCG), inhibit MMPs expression and activity. However, the effects of the black tea polyphenol, theaflavin-3,3′-digallate (TFDG), on osteoclast and MMP activity are unknown. Therefore, we examined whether TFDG and EGCG affect MMP activity and osteoclast formation and differentiation in vitro. TFDG or EGCG (10 and 100 μM) was added to cultures of rat osteoclast precursors cells and mature osteoclasts. Numbers of multinucleated osteoclasts and actin rings decreased in polyphenol-treated cultures relative to control cultures. MMP-2 and MMP-9 activities were lower in TFDG-and EGCG-treated rat osteoclast precursor cells than in control cultures. MMP-9 mRNA levels declined significantly in TFDG-treated osteoclasts in comparison to control osteoclasts. TFDG and EGCG inhibited the formation and differentiation of osteoclasts via inhibition of MMPs. TFDG may suppress actin ring formation more effectively than EGCG. Thus, TFDG and EGCG may be suitable agents or lead compounds for the treatment of bone resorption diseases.

Mineral and bone disorders including osteoporosis are common in dialysis patients and contribute to increased morbimortality. However, whether denosumab and alendronate are effective and safe treatments in hemodialysis patients is not known. Thus, we conducted a prospective, three-center study of 48 hemodialysis patients who were diagnosed as having osteoporosis and had not received anti-osteoporotic agents previously. Participants were randomized to either denosumab or intravenous alendronate, and all subjects received elemental calcium and calcitriol during the initial 2 weeks. The primary endpoint was the percent change in lumbar spine bone mineral density (LSBMD) at 12 months of treatment. The secondary endpoints included the following: change in BMD at other sites; change of serum bone turnover markers (BTM), coronary artery calcium score (CACS), ankle-brachial pressure index (ABI), brachial-ankle pulse wave velocity (baPWV), flow mediated dilation (FMD), and intima-media thickness at the carotid artery (CA-IMT); change from day 0 to day 14 in serum levels of Ca and P; time course of serum calcium (Ca), phosphorus (P), and intact parathyroid hormone (i-PTH); new fractures; and adverse events. Initial supplementation with elemental calcium and calcitriol markedly ameliorated the decrease of serum corrected calcium (cCa) levels induced by denosumab during the first 2 weeks, whereas serum cCa levels in the alendronate group were increased. Denosumab and alendronate markedly decreased serum levels of BTM and increased LSBMD at 12 months compared with baseline. However, no significant differences were found in the changes in LSBMD between the two groups. The serum cCa, P, and i-PTH levels in the two groups were maintained within the appropriate range. In contrast to the anti-osteoporotic effects, no significant differences after 12 months of treatment were found in the CACS, CA-IMT, ABI, baPWV, and FMD compared with pretreatment in both groups. Denosumab and alendronate treatment improved LSBMD, reduced BTM, and appeared to be safe in hemodialysis patients with osteoporosis. Ca ¼ calcium; P ¼ phosphate; ALP ¼ alkaline phosphatase; PTH ¼ parathyroid hormone; TRACP-5b ¼ tartrate-resistant acid phosphatase 5b; t-PINP ¼ total-type I collagen N-terminal propeptide; BAP ¼ bone-specific ALP; Hs-CRP ¼ high-sensitivity C-reactive protein; CACS ¼ coronary artery calcium score; CA-IMT ¼ intima-media thickness at the carotid artery; ABI ¼ ankle brachial pressure index; baPWV ¼ brachial-ankle pulse wave velocity; FMD ¼ flow mediated dilation.Data are presented as mean AE SD (range from 25th to75th percentile) or n (%). Journal of Bone and Mineral ResearchEFFECTS OF ANTI-OSTEOPOROTIC AGENTS IN HEMODIALYSIS PATIENTS 5 ISERI ET AL.

Rats with dwarfism accompanied by skeletal abnormalities, such as shortness of the limbs, tail, and body (dwarf rats), emerged in a Jcl-derived Sprague-Dawley rat colony maintained at the Institute for Animal Experimentation, St. Marianna University Graduate School of Medicine. Since the dwarfism was assumed to be due to a genetic mutation based on its frequency, we bred the dwarf rats and investigated their characteristics in order to identify the causative factors of their phenotypes and whether they could be used as a human disease model. One male and female that produced dwarf progeny were selected, and reproduction was initiated by mating the pair. The incidence of dwarfism was 25.8% among the resultant litter, and dwarfism occurred in both genders, suggesting that it was inherited in an autosomal recessive manner. At 12 weeks of age, the body weights of the male and female dwarf rats were 40% and 57% of those of the normal rats, respectively. In soft X-ray radiographic and histological examinations, shortening and hypoplasia of the long bones, such as the tibia and femur, were observed, which were suggestive of endochondral ossification abnormalities. An immunohistochemical examination detected an aggrecan synthesis disorder, which might have led to delayed calcification and increased growth plate thickening in the dwarf rats. We hypothesized that the principal characteristics of the dwarf rats were systemically induced by insufficient cartilage calcification in their long bones; thus, we named them cartilage calcification insufficient (CCI) rats.

BackgroundAnthropometric indices of central obesity, waist circumference (WC), conicity index (CI), and a-body shape index (ABSI), are prognostic indicators of cardiovascular (CV) risk. The association of CI and ABSI with other CV risk indices, markers of nutritional status and inflammation, and clinical outcomes in chronic kidney disease (CKD) stage 5 (CKD5) patients was investigated.MethodsIn a cross-sectional study with longitudinal follow up of 203 clinically stable patients with CKD5 (median age 56 years; 68% males, 17% diabetics, 22% with CV disease, and 39% malnourished), we investigated CI and ABSI and their associations with atherogenic index of plasma (AIP), Framingham CV risk score (FRS), Agatston scoring of coronary artery calcium (CAC) and aortic valve calcium (AVC), handgrip strength (HGS), high sensitivity C-reactive protein (hsCRP) and interleukin-6 (IL-6). CV events (CVE) and all-cause mortality during up to 10-years follow up were analyzed by multivariate survival analysis of restricted mean survival time (RMST).ResultsChronic kidney disease patients with middle and highest CI and ABSI tertiles (indicating greater abdominal fat deposition), compared to those with the lowest CI and ABSI tertiles, tended to be older, more often men and diabetic, had significantly higher levels of hsCRP, IL-6, AIP, FRS, CAC and AVC scores. CI and ABSI were positively correlated with CAC, FRS, AIP, hsCRP and IL-6. Both CI and ABSI were negatively correlated with HGS. In age-weighted survival analysis, higher CI and ABSI were associated with higher risk of CVE (Wald test = 4.92, p = 0.027; Wald test = 4.95, p = 0.026, respectively) and all-cause mortality (Wald test = 5.24, p = 0.022; Wald test = 5.19, p = 0.023, respectively). In RMST analysis, low vs. high and middle tertiles of CI and ABSI associated with prolonged CVE-free time and death-free time, and these differences between groups increased over time.ConclusionAbdominal fat deposit indices, CI and ABSI, predicted CV outcomes and all-cause mortality, and were significantly associated with the inflammatory status in CKD patients.