Steroid changes adipokine concentration in the blood and bone marrow fluid.

Our previous study has shown that plasminogen activator inhibitor 1 (PAI-1) gene expression and secretion from bone marrow adipocytes increased markedly with dexamethasone administration. The purpose of the present study was to measure the secretion of various adipokines from human bone marrow and blood, and investigate how adipokine secretion changes in a steroid environment. Human blood and bone marrow fluid were collected from a steroid treatment group and a control group during hip replacement surgery, and an enzyme-linked immunosorbent assay (ELISA) was used to measure the adiponectin, leptin, and PAI-1 levels. Adiponectin and leptin showed no significant differences between bone marrow and blood levels, but PAI-1 was significantly higher in bone marrow. The steroid treatment group had higher levels of leptin and PAI-1 in both the blood and bone marrow than the control group. PAI-1 was present at high concentrations in the bone marrow and increased by steroid treatment. High levels of PAI-1 in bone marrow may influence intraosseous hemodynamics and may induce necrotic bone disorders.

Pravastatin reduces steroid-induced osteonecrosis of the femoral head in SHRSP rats.

BACKGROUND AND PURPOSE: Although the definite cause of steroid-induced osteonecrosis of the femoral head (ONFH) is unknown, peripheral circulatory failure, lipid metabolism disturbance, and increased oxidative stress are considered to be possible causes. We investigated whether pravastatin as a statin treatment reduces (1) the incidence of ONFH, (2) the adipocyte area, and (3) bone marrow changes in the femoral head. METHODS: We divided up 81 thirteen-week-old spontaneously hypertensive stroke-prone (SHRSP)/Izm male rats into 4 groups: a control group (group C), a group given pravastatin (group P), a group given steroid (group S), and a group given both pravastatin and steroid (Group PS). The steroid was administered at 15 weeks of age. Pravastatin, as a statin, was administered in the drinking water for 4 weeks. The rats were killed when 17 weeks old. Osteonecrosis was diagnosed based on histopathological examination. Oxidative stress was assessed from immunostaining. RESULTS: The incidence of histological osteonecrosis was lower in the groups given pravastatin. The percentage of adipocyte area in the bone marrow was lower in the PS group than in the S group. Immunohistochemical staining for oxidative stress showed that staining was less in the PS group than in the S group. Pravastatin had no effect on the blood-derived biochemical findings on lipid metabolism. However, it reduced the incidence of steroid-induced ONFH in these SHRSP rats. We presume that this occurred by reducing oxidative stress and by reducing the percentage of adipocyte area in the femoral heads. INTERPRETATION: Our data suggest that pravastatin may be effective in reducing steroid-induced ONFH.

Pentosan reduces osteonecrosis of femoral head in SHRSP.

Increased oxidative stress is considered one of the main causes of steroid-induced osteonecrosis of the femoral head (ONFH). The aim of this study was to evaluate the effects of a steroid hormone and pentosan polysulfate sodium (pentosan), a heparin analog, in stroke-prone spontaneously hypertensive rats (SHRSP) as a model of ONFH. One hundred twenty-three 13-week-old male SHRSP/Izm rats were divided into four groups: a control group (group C), pentosan-administered group (group P), steroid-administered group (group S), and group administered pentosan plus steroid (group PS). Methylprednisolone acetate, as the steroid hormone, at a dose of 4 mg (15 mg/kg) was administered at 15 weeks of age. Pentosan at a dose of 3 mg/day/kg was continuously administered intraperitoneally from 13 weeks of age for 4 weeks. Rats were sacrificed at 17 weeks of age, and heart blood and both femora were collected. Triglyceride levels were significantly lower in group PS than in group S, indicating that pentosan improves lipid metabolism. The incidence of histologic ONFH was significantly lower in group P, at 14.8% (10/71 femoral heads), than in group C, at 30.4% (17/56 femoral heads), and significantly lower in group PS, at 40.8% (29/71 femoral heads), than in group S, at 91.3% (42/46 femoral heads), indicating that pentosan markedly inhibits ONFH. Immunohistochemical staining for oxidative stress showed that the stainability was significantly lower in group PS than in group S. Pentosan seems to reduce the incidence of ONFH in SHRSP by improving lipid metabolism and decreasing oxidative stress.

Sodium pentosan polysulfate resulted in cartilage improvement in knee osteoarthritis--an open clinical trial.

BACKGROUND: Pentosan polysulfate sodium (pentosan) is a semi-synthetic drug manufactured from beech-wood hemicellulose by sulfate esterification of the xylopyranose hydroxyl groups. From in vitro and animal model studies, pentosan has been proposed as a disease modifying osteoarthritis drug (DMOAD). The objective of this study was to assess the efficacy, safety, and patient satisfaction in patients with mild radiographic knee osteoarthritis (OA) findings and OA-associated symptoms and signs. METHODS: Twenty patients were assessed clinically at Nagasaki University Hospital. The radiographic indications of OA were grade 1 to 3 using the Kellgren-Lawrence Grading System (K/L grade). Pentosan used in this study was manufactured and supplied in sterile injectable vials (100 mg/ml) by bene GmbH, Munich, Germany. The study was a single-center, open-label trial. Treatment consisted of 6 weekly subcutaneous injections (sc) of pentosan (2 mg/kg). Patients were clinically assessed at entry and 1 to 8, 11, 15, 24 & 52 weeks post treatment. The results were analyzed using one way ANOVA and Dunnett's method. RESULTS: Hydrarthroses were reduced quickly in all cases. The clinical assessments, i.e., knee flexion, pain while walking, pain after climbing up and down stairs, etc, were improved significantly and these clinical improvements continued for almost one year. The dose used in this study affected the blood coagulation test, but was within safe levels. Slightly abnormal findings were noted in serum triglycerides. CONCLUSIONS: Pentosan treatment in twenty patients with mild knee OA seemed to provide improvements in clinical assessments and C2C level of cartilage metabolism.

Revision with impacted bone allografts and the Kerboull cross plate for massive bone defect of the acetabulum.

We retrospectively reviewed 31 hips with massive bone defect because of aseptic loosening of the acetabulum treated with impacted bone allografts with the Kerboull-type acetabular device. Mean age at surgery was 67.9 years, and mean duration of follow-up was 6.3 years. Thickness of the bone graft was evaluated by postoperative radiography. Seven hips showed radiological failure associated with 6 breakages of the device, and 24 hips showed stability on follow-up radiographs. Of the 13 hips showing a bone graft thickness of greater than 20 mm on follow-up radiographs, 7 were classified as failure group. If an acetabular reinforcement device with a bone graft of more than 20 mm thickness is necessary, then a structural allograft should be considered in the weight-bearing area of the support ring in addition to the morselized bone graft.

Osteonecrosis of femoral head in the stroke-prone spontaneously hypertensive rats, especially old rats.

The average life span of stroke-prone spontaneously hypertensive rats (SHRSP) is about eight months. Male SHRSPs at 40 weeks old were used to study the idiopathic osteonecrosis of the femoral head (ION). The control group showed about 40% old necrosis and 20% early necrosis. The group administered with steroid hormone showed an increasing degeneration of adipocyte in the bone marrow, and 20% fresh necrosis was recognized. Furthermore, we observed the adipocyte change as well as early necrosis occurring among old necrosis sites. The study of aged rats may provide further understanding into the pathogenesis of ION.

Osteonecrosis in stroke-prone spontaneously hypertensive rats: effect of glucocorticoid.

BACKGROUND: High-dose administration of a steroid hormone has been associated with a major risk of osteonecrosis. In this study we investigated the effects of a steroid hormone on the incidence of osteonecrosis of the femoral head in stroke-prone spontaneously hypertensive rats/Nagasaki (SHRSP/Ngsks). METHODS: A total of 71 SHRSP/Ngsks were divided into two groups: a control group (C group, n = 40) and a steroid hormone group (S group, n = 31) given 5 mg (about 20 mg/kg) of methylprednisolone acetate during the 17th week of age. We compared the groups' laboratory data, histological appearance, incidence of osteonecrosis, and expression of oxidative stress on immunohistochemical analysis using the monoclonal antibodies anti-4HNE and anti-8OHdG. RESULTS: The S group showed an increase in total cholesterol, with the amounts of high-density lipoprotein, low-density lipoprotein, and triglycerides all significantly higher than in the C group. Histological examination showed that the frequency of necrosis of the femoral head was significantly higher in the S group (95.2%) than in the C group (51.2%). Most of the histological features of the osteonecrosis demonstrated typical features of a similar sort in the two groups. However, the S group showed bone marrow spaces in the femoral head that were occupied by an increased number of adipocytes and that were swollen, partially degenerative, and necrotic. On immunohistochemical analysis, the stains of anti-4HNE and anti-8OHdG antibody were stronger in the S group than in the C group. CONCLUSIONS: This study confirmed, to a remarkable degree, the suspicion that the administration of steroid hormone increases the number of adipocytes in marrow. Fat degeneration and necrosis, considered early signs of osteonecrosis, were also observed. It has been hypothesized that osteonecrosis is produced by the ischemic change accompanying compartment pressure load in marrow, where fat degeneration, necrosis, and endothelial cell injury might occur together with oxidative stress.