menaquinone-6 and Glomerulonephritis

Although vitamin K2 has been shown to prevent prednisolone-induced loss of bone mineral density of the lumbar spine in patients with chronic glomerulonephritis, the magnitude of this effect remains to be clarified. The aim of this prospective study is to compare the protective effect of vitamin K2 with that of vitamin D3 on prednisolone-induced loss of bone mineral density in patients with chronic glomerulonephritis.. Sixty patients (28 men, 32 women) were randomly divided into 4 groups (n = 15 each group): control (group C), vitamin D3 alone (alfacalcidol, 0.5 microg/d; group D), vitamin K2 alone (menatetrenone, 45 mg/d; group K), and vitamins D3 plus K2 (group D + K). Alfacalcidol and menatetrenone therapy were started at the same time as prednisolone. Bone mineral density of the lumbar spine (L2 to L4) was determined by means of dual-energy X-ray absorptiometry, and various biochemical parameters of calcium and bone homeostasis were assessed before and at the end of week 8 of treatment.. Treatment with prednisolone alone caused loss of bone mineral density, which could be fully prevented in groups D, K, and D + K. However, marked reductions in levels of several biochemical markers of both bone formation and resorption also were observed in all groups. The preventive effect in groups K and D + K on loss of bone mineral density induced by prednisolone was similar to that in group D. The elevation in serum calcium levels observed in group D was attenuated in group D + K.. Protective effects of vitamin K2 or vitamins D3 and K2 on prednisolone-induced loss of bone mineral density are similar to that of vitamin D3.

Topics: Adolescent; Adult; Bone Density; Bone Resorption; Cholecalciferol; Chronic Disease; Female; Glomerulonephritis; Glucocorticoids; Humans; Lumbar Vertebrae; Male; Middle Aged; Parathyroid Hormone; Prednisolone; Prospective Studies; Vitamin K 2

Glucocorticoid-induced osteoporosis has been reported to be caused by enhanced bone resorption and suppressed bone formation. To clarify whether administration of vitamin K, which enhances bone formation, prevents prednisolone-induced loss of bone mineral density (BMD), a randomized, prospective, controlled study was conducted on 20 patients with chronic glomerulonephritis scheduled for treatment with prednisolone. All patients were initially treated with 0.8 mg/kg body weight/day of prednisolone (maximum of 40 mg) for 4 weeks, tapering to 20 mg/day over approximately 6 weeks. Ten patients received prednisolone alone (Group 1), and the other 10 patients received prednisolone plus 15 mg of menatetrenone, vitamin K, three times per day (Group 2). BMD of the lumbar spine measured by dual-energy X-ray absorptiometry (DXA) and biochemical markers of bone metabolism in blood and urine were evaluated before and 10 weeks after administration of prednisolone alone or with menatetrenone. In Group 1, treatment with prednisolone significantly reduced BMD of the lumbar spine from 1.14 +/- 0.12 to 1.10 +/- 0.11 g/cm2 (P = 0.0029). Serum intact osteocalcin and procollagen type I C-peptide (PICP) concentrations, biochemical markers of bone formation, were markedly reduced. A biochemical marker of bone resorption, urinary excretion of deoxypyridinoline, was significantly reduced. In Group 2, prednisolone-induced reduction of BMD was prevented by menatetrenone administration (1.09 +/- 0.09 to 1.07 +/- 0.07 g/cm2, P = 0.153). Menatetrenone prevented reduction of PICP concentration by prednisolone but not in serum intact osteocalcin concentration and urinary excretion of deoxypyridinoline. Thus, treatment with prednisolone resulted in loss of BMD of the lumbar spine associated with suppression of both bone formation and bone resorption. Menatetrenone is a useful agent in preventing prednisolone-induced loss of BMD.

Topics: Absorptiometry, Photon; Adolescent; Adult; Anti-Inflammatory Agents; Bone Density; Calcium; Chronic Disease; Drug Therapy, Combination; Female; Glomerulonephritis; Hemostatics; Humans; Male; Middle Aged; Osteoporosis; Phosphates; Prednisolone; Vitamin K; Vitamin K 2