Effects of insulin resistance on myometrial growth.

To observe the effects of insulin resistance on gonadal steroid hormone stimulation and the myometrial growth of female rats in order to elucidate the relationship between insulin resistance and the development of uterine leiomyomas. We divided 180 nonpregnant female Wistar rats into three groups as follows: group A, as the control group; group B, as the "model by exogenous sex hormone" group; and group C, as the "model by exogenous sex hormone plus insulin-resistance" group. All the animals were raised for 16 weeks. Uterine coefficient and homeostasis model assessment of insulin resistance (HOMA-IR) index were calculated. Myometrial depth and expression levels of the oestrogen receptor (ER), progesterone receptor (PR), and proliferating cell nuclear antigen (PCNA) were measured. HOMA-IR index, serum oestrogen level, uterine coefficient, and myometrial depth were lower in group B than in group C (P < 0.05). The expression levels of ER, PR, and PCNA were higher in group C than in group B (P < 0.05). An auxo-action of insulin resistance in myometrial growth was observed when exogenous oestrogen and progesterone were administered to the female rats in this study. Thus, we suspected that insulin resistance may affect the development of uterine leiomyomas.

[Influence of heat shock factor 1 gene transfection on the expression of inflammatory mediators in macrophages induced by burn serum].

OBJECTIVE: To investigate the influence of heat shock factor1 (HSF1) on gene expression of inflammatory mediators in RAW264.7 murine macrophage cells induced by burn serum. METHODS: Sera were separated from blood of normal rats and rats with severe burns, and the recombinant vector pcDNA3. 1/HSF1 was constructed. RAW264.7 macrophages were divided into non-transfection group, vacant vector group (with burn and normal sera stimulation, respectively after vacant vector transfection) and recombinant vector group (with burn and normal sera stimulation, respectively after recombinant vector transfection). Some recombinant vector transfected macrophages without serum stimulation were prepared for the determination of HSF 1 expression with Western blotting. The mRNA expressions of TNF-alpha, HMGB 1 and IL-10 were determined with RT-PCR. RESULTS: The cell line attained after recombinant vector transfection was comparatively stable,with partial activation of HSF 1. Burn sera markedly upregulated TNF-alpha, HMGB1 mRNA expression (0.910 +/- 0.100, 0.860 +/- 0.020, respectively), but downregulated IL-10 expression (0.430 +/- 0.010, respectively) in normal macrophages, while these genes maintained in a very low level in normal macrophages with normal serum stimulation . macrophages with recombinant vector transfection and burn serum stimulation could obviously inhibit the expression of TNF-alpha and HMGB 1, but enhance the IL-10 gene expression (0.130 +/- 0.100, 0.450 +/- 0.020 , 0.450 +/- 0.020, respectively )when compared with that with vacant vector transfection and burn serum stimulation (0.800 +/- 0.050, 0.880 +/- 0.030, 0.420 +/- 0.010, respectively). CONCLUSION: HSF1 can inhibit the expression of some pro-inflammatory mediators in macrophages after a severe burns, indicating that appropriate upregulation of anti-inflammatory mediators might exert protective effects on the organism.