RESUMO
<p><b>Objective</b>To investigate the effects of fosfomycin tromethamine (FT) on the expressions of tumor necrosis factor-α (TNF-α), interleukin-8 (IL-8), and interleukin-6 (IL-6) in the prostate tissue of the rats with chronic bacterial prostatitis (CBP).</p><p><b>METHODS</b>We randomly divided 70 male SD rats into 7 groups of equal number: blank control, CBP model control, positive control, 14 d low-dose FT, 7 d low-dose FT, 14 d high-dose FT, and 7 d high-dose FT. The CBP model rats in the latter five groups were treated intragastrically with levofloxacin at 100 mg/kg/d for 30 days and FT at 200 mg/kg/d for 14 and 7 days and at 300 mg/kg/d for 14 and 7 days, respectively. Then we collected the prostate tissue from the animals for determination of the levels of TNF-α, IL-8 and IL-6 by ELISA.</p><p><b>RESULTS</b>Compared with the blank controls, the CBP model rats showed significantly increased levels of TNF-α (［19.83 ± 6.1］ vs ［32.93 ± 6.21］ ng/g prot, P <0.01), IL-8 (［8.26 ± 0.52］ vs ［16.2 ± 2.84］ ng/g prot, P <0.01) and IL-6 (［1.55 ± 0.11］ vs ［2.51 ± 1.06］ ng/g prot, P <0.05) in the prostate tissue. In comparison with the CBP model controls, the levels of TNF-α and IL-8 were remarkably decreased in the groups of positive control (［20.54 ± 5.78］ ng/g prot, P <0.01; ［12.43 ± 4.02］ ng/g prot, P <0.05), 14 d low-dose FT (［21.95 ± 6.48］ ng/g prot, P <0.01; ［11.11 ± 2.86］ ng/g prot, P <0.01), 7 d low-dose FT (［23.8 ± 6.93］ ng/g prot, P <0.05; ［12.43 ± 4.02］ ng/g prot, P <0.05), 14 d high-dose FT (［19.97 ± 2.58］ ng/g prot, P <0.01; ［8.83 ± 1.32］ ng/g prot, P <0.01), and 7 d high-dose FT (［21.97 ± 3.38］ ng/g prot, P <0.01; ［12.68±1.97］ ng/g prot, P <0.05). No statistically significant differences were observed between the positive control and FT groups in the contents of TNF-α, IL-8 or IL-6 (P >0.05). The expression of IL-6 was markedly reduced in the 14 d high-dose FT group as compared with the model controls (［1.76 ± 0.46］ vs ［2.51 ± 1.06］ ng/g prot, P<0.05) but exhibited no significant difference between the CBP model control and the other groups (P >0.05).</p><p><b>CONCLUSIONS</b>Fosfomycin tromethamine inhibits the expressions of TNF-α, IL-8 and IL-6 in the prostate tissue, suppresses its inflammatory reaction, promotes the repair of damaged prostatic structure, and thus contributes to the treatment of chronic bacterial prostatitis in rats.</p>