Curcumin Can Inhibits hepatitis B virus Replication
用姜黄素处理HBV稳定转染的HepG2.2.15细胞株，ELISA检测HBV表面抗原(HBsAg)和e抗原(HBeAg)表达水平。用Southern blot和real-time PCR分别检测细胞内HBV DNA复制中间体和cccDNA。用Western blot检测组蛋白H3和H4的乙酰化水平。通过染色质免疫沉淀(ChIP)检测H3/ h4结合的cccDNA。采用去乙酰化酶抑制剂木鳖碱A和丁酸钠对姜黄素的作用机理进行了研究。此外，我们还与姜黄素一起测试了针对HBV的短干扰RNA (siRNAs)。
姜黄素治疗导致HBsAg和HBeAg表达的时间和剂量依赖性降低，细胞内HBV DNA复制中间体和HBV cccDNA显著降低。治疗后20μmol 2 d / L姜黄素,乙肝表面抗原在HepG2.2.15细胞和cccDNA的水平减少了57.7%(P < 0.01)和75.5%(P < 0.01),分别与摘要细胞水平。同时，使用姜黄素治疗组蛋白H3乙酰化水平的时间和剂量依赖性降低，同时H3和h4结合的cccDNA水平降低。此外，去乙酰化酶抑制剂trichostatin A和丁酸钠可以阻断姜黄素的作用。此外，转染以HBV为靶点的siRNAs增强了姜黄素的抑制作用。
Curcumin inhibits hepatitis B virus infection by down-regulating cccDNA-bound histone acetylation
AIM To investigate the potential effect of curcumin on hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) and the underlying mechanism.
A HepG2.2.15 cell line stably transfected with HBV was treated with curcumin, and HBV surface antigen (HBsAg) and e antigen (HBeAg) expression levels were assessed by ELISA. Intracellular HBV DNA replication intermediates and cccDNA were detected by Southern blot and real-time PCR, respectively. The acetylation levels of histones H3 and H4 were measured by Western blot. H3/H4-bound cccDNA was detected by chromatin immunoprecipitation (ChIP) assays. The deacetylase inhibitors trichostatin A and sodium butyrate were used to study the mechanism of action for curcumin. Additionally, short interfering RNAs (siRNAs) targeting HBV were tested along with curcumin.
Curcumin treatment led to time- and dose-dependent reductions in HBsAg and HBeAg expression and significant reductions in intracellular HBV DNA replication intermediates and HBV cccDNA. After treatment with 20 μmol/L curcumin for 2 d, HBsAg and cccDNA levels in HepG2.2.15 cells were reduced by up to 57.7% (P < 0.01) and 75.5% (P < 0.01), respectively, compared with levels in non-treated cells. Meanwhile, time- and dose-dependent reductions in the histone H3 acetylation levels were also detected upon treatment with curcumin, accompanied by reductions in H3- and H4-bound cccDNA. Furthermore, the deacetylase inhibitors trichostatin A and sodium butyrate could block the effects of curcumin. Additionally, transfection of siRNAs targeting HBV enhanced the inhibitory effects of curcumin.
Curcumin inhibits HBV gene replication via down-regulation of cccDNA-bound histone acetylation and has the potential to be developed as a cccDNA-targeting antiviral agent for hepatitis B. Key Words: Curcumin, Hepatitis B virus, Covalently closed circular DNA, Histone deacetylation Core tip: We showed that curcumin inhibited hepatitis B virus (HBV) replication and expression via reductions in covalently closed circular DNA-bound histone acetylation. Furthermore, siRNAs targeting HBV acted synergistically with curcumin, resulting in enhanced inhibition of HBV.
World J Gastroenterol. Sep 14, 2017; 23(34): 6252-6260
Published online Sep 14, 2017. doi: 10.3748/wjg.v23.i34.6252