[Analysis of genes related to female bone peak and osteoporosis based on bioinformatics].

OBJECTIVE: To explore and verify the genes related to female peak bone mass(PBM) and osteoporosis (OP) based on bioinformatics. METHODS: Using GEO data, DNA microarray technology to conduct genome-wide analysis of adult female monocytes with high and low PBM. Cluster analysis, GO enrichment and KEGG analysis were used to analyze the differential genes, and the interaction network of differential genes was further analyzed. OP rat model was established and femur neck tissue staining was performed to further verify the expression of differential genes. RESULTS: A total of 283 genes were obtained by differential gene screening. Compared with the high PBM samples, 135 genes were up-regulated and 148 genes were down-regulated in the low PBM samples. A total of 7 pathways and 12 differential genes were enriched, and there were differences in the expression of several genes involved in mineral absorption and transport, cellular immunity and other aspects. Among them, voltage-gated Ca2+ channel 1.3(CaV1.3) encoded by CACNA1D gene was significantly enhanced in the femoral neck tissue of OP rat model. CONCLUSION: The above results suggest that the difference in the expression level of CaV1.3 gene may lead to the occurrence of OP in women with low PBM, which provides us with a potential target for the prevention and treatment of OP.

Prevalence and possible risk factors of low bone mineral density in untreated female patients with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by chronic inflammation. Different studies have shown decreased bone mineral density (BMD) in patients with SLE. The objective of this study was to investigate the prevalence and possible risk factors of low BMD in untreated female patients with SLE in Chinese population. A total of 119 untreated female patients with SLE were included. BMD was measured at lumbar spine and at total hip by dual-energy X-ray absorptiometry. The associations between decreased BMD and demographic variables, clinical variables, and bone metabolism variables were analyzed. These SLE patients had the following characteristics: mean age was 32.6 ± 11.9 years, mean disease duration was 22.1 ± 34.5 months, and mean SLEDAI was 11.4 ± 5.4. Osteopenia was present in 31.1% of the patients and osteoporosis in 8.5%. A significant negative association between low density lipoprotein cholesterol (LDL-c) and BMD at the lumbar spine (correlation coefficient = -0.242; P = 0.023) and total hip (correlation coefficient = -0.259; P = 0.019) was shown. These results seem to indicate that increased LDL-c may be an important risk factor for low BMD at lumbar spine and total hip in untreated female SLE patients.

[Role of glucocorticoid receptor in the pathogenesis of systemic lupus erythematosus].

OBJECTIVE: To investigate the expressions of GRα mRNA and GRß mRNA in the peripheral blood mononuclear cells (PBMCs) of systemic lupus erythematosus (SLE) patients, in order to reveal the role of GR mRNA in the pathogenesis of SLE and analyze the relationship between GR mRNA and SLEDAI score, dsDNA, cardiovascular involvement. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) technique was applied to semiquantitatively analyze GRα mRNA and GRß mRNA expressions in 104 SLE patients and 56 volunteers. RESULTS: The level of GRα mRNA was lower in the SLE group (the relative level was 1.24±0.97)than in the control group (the relative level was 2.31±1.42, P<0.05), and the level of GRß mRNA was higher in the SLE group(the relative level was 0.61±1.23) than in the control group(the relative level was 0.18±0.21, P<0.05). The level of GRα was lower in the active group (the relative level was 0.68±0.40) than in the inactive group(the relative level was 1.65±1.06, P<0.01), but the level of GRß was higher in the active group(the relative level was 0.88±1.56) than in the inactive group(the relative level was 0.24±0.23, P<0.01); GRα mRNA was related negatively to the SLEDAI score and dsDNA, but GRß mRNA was related positively to the SLEDAI score and dsDNA(P<0.01).The level of GRα mRNA was lower in the dsDNA positive group(the relative level was 0.89±0.66) than in the dsDNA negative group (the level was 1.54±1.10), the level of GRß mRNA was higher in the dsDNA positive group (the relative level was 0.95±1.60) than in the dsDNA negative group (the relative level was 0.22±0.21). The level of GRß mRNA and the value of GRß mRNA/ GRα mRNA was obviously higher in the SLE group with cardiac involvement (the relative level was 1.02 ±1.76, the valve of GRß / GRα was 1.10±2.02)than in the SLE group without cardiac involvement (the relative level was 0.28±0.31, the valve of GRß / GRα was 0.32±0.32, P<0.05), and the level of GRα mRNA wasn't significant in the two groups (P>0.05). CONCLUSION: The levels of GRα mRNA and GRß mRNA maybe play an important role in the pathogenesis of SLE. And the levels of GRα mRNA and GRß mRNA are related to the activity of SLE. The level of GRß mRNA and the value of GRß mRNA/ GRα mRNA are related with cardiovascular involvement in SLE.