Yoneda Masato, Wada Koichiro, Katayama Kazufumi, Nakajima Noriko, Iwasaki Tomoyuki, Osawa Emi, Mukasa Koji, Yamada Yasuhiko, Blumberg Richard S, Sekihara Hisahiko, Nakajima Atsushi
The Third Department of Internal Medicine, Yokohama City University School of Medicine, 3-9 Fuku-ura, Kanazawa, Yokohama, Japan.
Biochem Pharmacol. 2004 Dec 1;68(11):2283-9. doi: 10.1016/j.bcp.2004.07.044.
Dehydroepiandrosterone (DHEA), one of the major androgens secreted by the adrenal cortex, has been shown to have potential immunoreguratory properties. In this study, we examined the effect of DHEA in a mouse model of hepatitis. Mice were treated with DHEA and injected with concanavalin A (Con A) or lipopolysaccharide (LPS)/D-galactosamine (GalN). Cytokine expression was measured by quantitative RT-PCR and ELISA. Apoptosis was detected by the TUNEL method and by DNA fragmentation analysis. In the DHEA-treated mice, the serum levels of ALT and expression of inflammatory mediators were significantly decreased. The number of apoptotic cells was also much lower than that observed in control, untreated mouse liver tissue. There were fewer tumor necrosis factor-alpha (TNF-alpha)-induced apoptotic cells in H4IIE hepatoma cells treated with DHEA than in non-treated cells. DHEA decreased the expression levels of mRNA transcripts encoding TNF-alpha and iNOS. These results suggest that DHEA can reduce T-cell-mediated injury in the liver as manifest by inhibition of the expression of several inflammatory mediators and hepatocyte apoptosis. DHEA should, thus, be considered as a novel candidate for the therapy of liver injury.
脱氢表雄酮(DHEA)是肾上腺皮质分泌的主要雄激素之一,已被证明具有潜在的免疫调节特性。在本研究中,我们在肝炎小鼠模型中检测了DHEA的作用。用DHEA处理小鼠,并注射刀豆蛋白A(Con A)或脂多糖(LPS)/D-半乳糖胺(GalN)。通过定量RT-PCR和ELISA测量细胞因子表达。通过TUNEL法和DNA片段化分析检测细胞凋亡。在DHEA处理的小鼠中,血清ALT水平和炎症介质表达显著降低。凋亡细胞数量也远低于未处理的对照小鼠肝组织中观察到的数量。用DHEA处理的H4IIE肝癌细胞中,肿瘤坏死因子-α(TNF-α)诱导的凋亡细胞比未处理细胞少。DHEA降低了编码TNF-α和诱导型一氧化氮合酶(iNOS)的mRNA转录物的表达水平。这些结果表明,DHEA可以减轻肝脏中T细胞介导的损伤,表现为抑制几种炎症介质的表达和肝细胞凋亡。因此,DHEA应被视为肝损伤治疗的新候选药物。