RESUMEN
Peripheral blood mononuclear cells (PBMCs) constitute the main extrahepatic place of, hepatitis C virus (HCV) replication. We aimed to determine the impact of CHC infection and microRNA-, 122 expression on cholesterol expression in PBMCs. HCV RNA strand, intracellular cholesterol, HMGCoA, reductase and miR-122 expression in PBMC were determined in 54 CHC patients. The study shows that significant decrease of intracellular cholesterol level in PBMC (p=0.000000), accompanied by serum hypocholesterolemia is the characteristic feature of chronic hepatitis C infection. Although, microRNA-122 expression was detectable in PBMCs of CHC patients (52.5%), the alteration of intracellular cholesterol level was independent of miR-122 expression.
Asunto(s)
Colesterol/análisis , Hepatitis C Crónica/patología , Leucocitos Mononucleares/química , Adulto , Colesterol/sangre , Femenino , Hepacivirus/genética , Humanos , Hidroximetilglutaril-CoA Reductasas/análisis , Masculino , MicroARNs/análisis , MicroARNs/genética , ARN Viral/análisis , ARN Viral/genética , Adulto JovenRESUMEN
A tight relationship has been revealed between cellular microRNAs (miRNAs) and the course of hepatitis C virus (HCV) replication in human hepatoma cells. Although the detection of the antigenomic HCV RNA strand in peripheral blood mononuclear cells (PBMCs) has provided evidence for viral replication in PBMCs, no reports have shown how miRNAs are affected upon HCV RNA synthesis in PBMCs. The aim of the present study was to assess if and how the expression levels of miRNA-155 and miRNA-196b in PBMCs are related to HCV replication in PBMCs of chronic hepatitis C (CHC) patients. Supporting analyses were performed to evaluate the expression of precursor pri-miR-155 (BIC) and Dicer protein. The genomic and antigenomic HCV RNA strands in PBMCs were detected by strand-specific qRT-PCR. The expression levels of miRNAs, BIC RNA and Dicer protein were assayed on PBMCs by qRT-PCR and Western blotting, respectively. miRNA-155 and miRNA-196b were detected in all studied PBMC samples, but their levels varied according to the presence of the antigenomic HCV RNA strand in PBMCs. Increased expression levels of miRNA-155 and miRNA-196b were associated with the presence of the antigenomic HCV RNA strand in PBMCs. In this group of patients higher frequency of BIC RNA and Dicer protein detection was also found. This study demonstrates that HCV RNA replication in PBMCs of CHC patients is connected with the increased and coordinated expression of miRNA-155 and miRNA-196b.
Asunto(s)
Hepacivirus/genética , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/virología , MicroARNs/genética , Células Cultivadas , Humanos , Reacción en Cadena de la Polimerasa , ARN Viral/genéticaRESUMEN
Although the mechanism of HCV RNA replication is still poorly characterized, we know that HCV active replication complex contains membrane structures. Biochemical analysis showed that these membrane structures were resistant to nonionic detergents at low temperature and contained caveolin-2, characteristic of lipid rafts. Further analysis suggested that lipid rafts protect HCV replication complex against degradation. Lipid rafts provide also a mechanism of how HCV may modulate cellular processes, what can lead to disruption of antiviral immune response and then to chronic infection. Association hepatitis C virus with lipid rafts can be also a source of new antiviral therapies.