Mineral bone disorder and osteoporosis in hemodialysis patients

Abstract Background: Bone disease is common in patients undergoing hemodialysis. It is the result of bone turnover abnormalities and the decrease of bone mineral density (BMD). We aimed to determine the usefulness of serum bone turnover markers and BMD measurement by dual-energy x-ray absorptiometry (DXA) in hemodialysis patients. Methods: We conducted a cross-sectional study including 90 hemodialysis for more than 12 months. Bone mineral density was assessed by DXA. Peripheral blood samples were obtained from each patient before dialysis in a fasting state within a week of the DXA. Biochemical variables of calcium and phosphate were measured. One bone formation marker (bone-specific alkaline phosphatase (bAP), one bone resorption marker (carboxy-terminal telopeptides of type 1 collagen (CTX)) were measured. Total alkaline phosphatase (TAP), intact parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23) which is a bone-derived hormone were also measured. Results: CTX values were 6.25 times higher than the normal limit of the assay. Bone alkaline phosphatase levels were less than 10 ng/mL in 28.8% of cases. 23% of patients have osteoporosis and 45% have osteopenia. Femoral BMD had negative correlations with age and PTH levels. FGF23 levels were significantly increased in patients with osteoporosis affecting the lumbar. The levels of bAP and CTX showed a positive correlation. Both circulating bAP and CTX levels showed also positive correlations with PTH levels. Fractures, observed in 12.2% of cases, were associated with low PTH values and the existence of osteoporosis. Conclusions: Our study showed that osteoporosis and fracture are common in dialysis patients. The reduced BMD was associated with advanced age and elevated levels of PTH. Markers of bone turnover and FGF23 may play a role in the diagnosis of bone disease in hemodialysis patients. DXA measurement is necessary for the monitoring for bone loss.(AU)

Differential immunohistochemical expression of type I collagen and matrix metalloproteinase 2 among major salivary glands of young and geriatric mice

Abstract Objective This study aimed to demonstrate the immunohistochemical changes associated with MMP-2 and type 1 collagen separately for the first time in the major salivary glands (the parotid, submaxillary, and sublingual glands) that occur with aging in mice. Material and Methods Fourteen Balb/c white mice (50-80 g) were used in this study. The animals were divided into two equal groups. Group I consisted of young animals (2-month-old) (n=7) and Group II consisted of older animals (18-month-old) (n=7). After routine histological follow-ups, Hematoxylin-eosin (H&E), Masson's Trichrome staining and immunohistochemical staining was performed for type I collagen and MMP-2. Results We observed that there were age-related decreases in the number of acinar cells, increase in eosinophilic zymogen granules in cells, collagen accumulation in fibrotic areas and dilatation in interlobular ducts. Also, while type I collagen and MMP-2 immunoreactivity were moderate in the salivary glands of the young mice, they were high in the salivary glands of the old mice (p=0.001). In the H-score assessment, MMP-2 immunoreactivity was lower at a significant level in young mice than in old mice (p=0.001). Conclusions This study showed that anatomical, physiological and morphological abnormalities occur in all three major salivary glands as a natural consequence of aging.

The Influence of Age, Ethnicity and Body Anthropometry on the Level of Serum Osteocalcin and Terminal-C Telopeptides of Type I Collagen in Men / Jurnal Sains Kesihatan Malaysia

Bone turnover markers (BTMs) are useful in the assessment of bone health status. However, the infl uence of age, ethnicity and body anthropometry on the level of BTMs in men remains understudied. This study aimed to determine the infl uence of these factors on the level of BTM, namely osteoclacin (OC) and C-terminal telopeptides of type 1 collagen (CTX-1) among Malay and Chinese men (N = 407) aged 20 years and above in Klang Valley. The subjects were recruited using purposive sampling method. Their height, body weight and body mass index were measured. Their blood was collected in the morning for serum OC and CTX-1 analysis using enzyme-linked immunoasorbent assays. Results showed that OC and CTX-1 levels were signifi cantly higher in Malay compared to Chinese men (p 0.005). There were signifi cant and negative correlations between OC and body mass index and weight, which were signifi cant for men aged 20-39 years only (p 0.05). As a conclusion, levels of BTMs in Malaysian men could be infl uenced by age, ethnicity and body anthropometry. Thus, these factors should be taken into consideration in the evaluation of bone health status of men using BTMs

Relationships of Serum Leptin Levels with Bone Metabolism in the Childhood Obesity / 대한소아소화기영양학회지

PURPOSE: The aim of this study was to evaluate the influence of leptin on biochemical markers of bone metabolism in childhood obesity. METHODS: A total of 50 male children (25 obese and 25 controls) were recruited from the pediatric outpatient clinic at the Chosun University Hospital from November 1st 2005 to May 30th 2006. BMI, body fat percentage, serum leptin, bone-specific alkaline phosphatase (B-ALP), C-terminal propeptide of type 1 collagen (CICP), total deoxypyridinoline crosslinks (total DPD) were measured. The correlations of leptin with BMI, body fat percentage, B-ALP, CICP, total DPD were analyzed by Pearson's correlation. In a multiple stepwise regression analysis, leptin after correction for body weight was evaluated if there was a correlation with biochemical markers of bone formation and resorption respectively. RESULTS: The leptin levels of the obese group were significantly higher than those of the control group (p=0.012). In the obese group, the leptin level was significantly positively correlated with the BMI (r=0.551, p=0.01) and the percentage of body fat (r=0.584, p=0.018). In the obese group, of bone markers, B-ALP (r=-0.613, p=0.026) and CICP (r=-0.583, p=0.037) were negatively correlated with leptin. B-ALP (r=-0.728, p=0.007) and CICP (r=-0.684, p=0.014) were negatively correlated with leptin when corrected for body weight. In the control group, bone markers were not correlated with leptin. In the multiple stepwise regression analyses, there was a negative correlation between the leptin and B-ALP (Y=-39.653X+356.341, p=0.026), CICP (Y=-13.437X+116.013, p=0.037) respectively in the obese group. CONCLUSION: Leptin was a significant factor in the bone formation but not in bone resorption in childhood obesity.

The Effects of Polyethylene(UHMWPE) Particles on MG63 Osteoblastlike Cells / 대한정형외과연구학회지

We performed an in vitro study to determine the effects of ultra high molecular weight polyethylene (UHMWPE) particles on the cell proliferation, matrix synthesis(type I collagen mRNA), and cytokines production(interleukin-lbeta and prostaglandin E2) of MG63 osteoblastlike cells. UHMWPE wear particles were isolated from osteolysis tissue of 8 patients during revision hip arthroplasties. Sub-micron UHMWPE powders were also isolated from fabricated virgin UHMWPE powders. Group I (control culture) contained no UHMWPE particles. In group II andIII, the UHMWPE wear particles and the UHMWPE powders were added to cultures of MG63 osteoblastlike cells with the different concentration of 0.2mg/ml, 0.02mg/ml, 0.002mg/ml, and 0.0002mg/ml. The average diameter of the retrieved UHMWPE particles was 0.4micrometa(ranged, 0.1 to 1.4 micrometa), and that of the fabricated UHMWPE powders was 0.6micrometa(ranged, 0.1 to 2.3micrometa). In group II and III, the UHMWPE particles induced an increase in osteoblastlike cell growth(p0.05). The release of IL-lbeta was higher in group II than in group III(p<0.05). These data support the hypothesis that direct suppression and cytokines release of MG63 osteoblastlike cells by UHMWPE particles may play a role in particle-mediated osteolysis.