Effect of calcitonin or the anabolic steroid Decadurabolin on serum beta 2 microglobulin in osteoporotic postmenopausal women.

beta 2-Microglobulin (beta 2m) is a small polypeptide of 99 amino acids with a molecular weight of 11.800. It is found in serum, on the surface of almost all mammalian cells and is part of the surface antigen of the cell membrane of human lymphocytes. Moreover, the heavy chain of major histocompatibility complex class I molecules normally associates in the membrane with beta 2m. According to Canalis, et al this polypeptide is a bone derived growth factor. In our study, serum beta 2m, osteocalcin bone Gla-protein (BGP) and calcium phosphorous metabolism were evaluated in a group of 18 osteoporotic women. Nine were treated with an anabolic steroid, DecaDurabolin and 9 with salmon calcitonin (sCT) for 3 months. The same variables were evaluated in a control group (6 osteoporotic women) treated with oral Ca (1,500 mg/day for 3 months). A significant increase in serum beta 2m and BGP (p < 0.001) was observed after anabolic steroid while a significant decrease in serum beta 2m and BGP (p < 0.01) was observed after sCT. No significant variation for serum beta 2m and BGP was observed in the control group. No significant variation of calcium-phosphorous metabolism was observed in either the control group or the treated group. BGP variations suggest that anabolic steroid stimulates bone formation while a decrease in BGP observed after sCT suggests that this hormone depresses bone turnover via a block in osteoclast activity. Moreover it could be suggested that anabolic steroid and sCT affect beta 2m producing cells.

Post biliopancreatic bypass arthritis. Dermatitis syndrome.

A case of arthritis dermatitis syndrome observed after a biliopancreatic bypass for morbid obesity is described. The syndrome had begun 10 days after surgery and involved the knees, ankles, elbows and wrists and erythema nodosum on the legs. After 15 days treatment with sulfasalazine and steroid the symptoms disappeared. The immunologic aetiology of the disease was postulated and the observation of the syndrome, for the first time, after a biliopancreatic bypass suggested that the manifestation of the disease is independent of the kind of the surgical procedures used for the treatment of the morbid obesity.

Osteoblast-osteoclast relationships in bone resorption: osteoblasts enhance osteoclast activity in a serum-free co-culture system.

Osteoblast-osteoclast relationships in bone resorption are unclear. We investigated whether osteoblasts constitutively influence osteoclast activity. We employed a serum-free co-culture system in which chicken osteoclasts and chick calvaria or, alternatively, isolated chick osteoblasts were cultured in two different compartments separated by a 0.45 micron porous membrane permeable to soluble molecules. Osteoclastic bone resorption, evaluated by release of 3H-proline from prelabeled bone fragments, was significantly enhanced by bone cells resident in the calvaria, as well as by isolated osteoblasts. Stimulation was specific, since periosteal cells, or skin fibroblasts, failed to mimic osteoblast activity. Conditioned medium from osteoblast cultures stimulated osteoclast function in a similar manner, indicating that paracrine signals, capable of crossing the porous membrane separating the two compartments, are released by the bone forming cells.

Mixed sclerosing bone dystrophy with features resembling osteopoikilosis and osteopathia striata.

A 64-year old man, presenting pain in his back and left sciatalgia, was found to have a mixed sclerosing bone dystrophy with features resembling osteopoikilosis and osteopathia striata. Oval and round densities were found in the humeral heads, elbows, wrists, hands, pelvis, knees, feet. Striata densities were in the diaphyses of metacarpal and metatarsal bones. Bone scan was negative. Standard biochemical examinations of the blood and urine were negative. According to our investigations no evidence of osteopoikilosis other sclerosing bone dystrophies were found in the family of our patient. These data were discussed.

The importance of vitamin C for hydroxylation of vitamin D3 to 1,25(OH)2D3 in man.

The effects of vitamin C on 1,25(OH)2D3 synthesis in humans were evaluated; the study included 20 females. They were divided into 2 groups. The first of the 10 subjects (age range 55-71) received ascorbic acid at a dose of 150 mg/die i.v. for 10 days; the second 10 subjects (age range 55-69) received a placebo i.v. for 10 days. In a later study (after a 30-day washout) the same two groups were tested for the second time with ascorbic acid at a dose of 1,000 mg/die i.v. for 10 days and placebo i.v. for 10 days. Serum calcium and phosphorus, serum Ca++, serum proteins, blood and urinary pH, serum 25(OH)D3 and 1,25(OH)2D3, serum PTH, urinary hydroxyprolin were tested before and after the treatments. In the first study a significant increase in serum 1,25(OH)2D3 was observed after ascorbic acid while no significant variation was observed for the other parameters. In the second study, a significant increase in serum Ca++ and a significant decrease in serum 1,25(OH)2D3 were observed after ascorbic acid while no significant variation was observed for the other parameters. The authors conclude that ascorbic acid promotes 1,25(OH)2D3 synthesis at a paraphysiologic dose (150 mg/die) in humans but this synthesis is inhibited at higher doses (1,000 mg/die). The latter effect by Ca++ or by an effect of ascorbate on 1 alpha-hydroxylase enzyme could be mediated.