Prevalence of hepatitis C virus genotypes and impact of T helper cytokines in achieving sustained virological response during combination therapy: a study from Central India

Role of mitochondrial oxidative stress on lymphocyte homeostasis in patients diagnosed with extra-pulmonary tuberculosis

Extra-pulmonary tuberculosis is often an underrated illness. Recent clinical studies have pointed out that lymphocyte homeostasis is dramatically disturbed as revealed through a series of signs and symptoms. Lymphocytes, the known effector cells of our immune system, play an important role in providing immunologic resistance against Mycobacterium infection. It is important to have quantitative insights into the lifespan of these cells; therefore, we aimed to study the precise effect of gastrointestinal tuberculosis infection on peripheral blood lymphocyte subpopulations and function. Our results indicated that gastrointestinal tuberculosis could increase mitochondrial oxidative stress, lower mitochondrial DNA copy number, promote nuclear DNA damage and repair response, decrease mitochondrial respiratory chain enzyme activities, and upregulate Bcl-2 and caspase-3 gene expression in lymphocytes. We further revealed that Mycobacterium infection induces autophagy for selective sequestration and subsequent degradation of the dysfunctional mitochondrion before activating cellular apoptosis in the peripheral lymphocyte pool. Together, these observations uncover a new role of mitochondrial-nuclear crosstalk that apparently contributes to lymphocyte homeostasis in gastrointestinal tuberculosis infection.

Distribution of Hepatitis C virus genotypes in city of Mashhad, North-east of Iran

PURPOSE

Six major hepatitis C virus genotypes have been characterised, which vary in their geographical distribution. The prevalence of hepatitis C virus (HCV) in an area is not constant, and depends on the changes in route of infection, which may change over time. In this study, the distribution of HCV genotypes in Mashhad, the capital of Razavi Khorasan province in north-east of Iran was investigated. Mashhad is a holy city of Shiate Moslems, which attracts more than 20 million tourists and pilgrims every year.

MATERIALS AND METHODS

Two hundred and seventy-eight HCV infected subjects (227 males and 51 females) were included in this study. HCV genotypes were analysed by type specific reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTS

Genotype 3a was detected in 49.6%, 1a in 36.3%, 1b in 12.6% and 2a in 0.4%. Two HCV genotypes were detected in 1.1% cases; 1a +3a in 1%, 3a + 1b in 0.4%. Genotypes 2b and 3b were not detected in any samples.

CONCLUSION

We demonstrated that despite the previous reports on the frequency of HCV genotypes in Iran, 3a is the predominant genotype in Mashhad.

Cancer chemopreventive effects of the flavonoid-rich fraction isolated from papaya seeds

Intervention to decelerate, arrest, or reverse the process of carcinogenesis by the use of either natural or synthetic agents individually or in combination has emerged as a promising and pragmatic medical approach to reduce cancer risk. In the present study, we examined the cancer chemopreventive potential of a flavonoid-rich fraction isolated from the seeds of Carica papaya, a plant traditionally referred to as papaw. The flavonoid-enriched benzene fraction of the aqueous extract exerted its anticancer properties in vitro through cytoprotection, antioxidative and antiinflammatory mechanisms and genoprotection in response to isocyanate-induced carcinogenicity. Medium-term anticarcinogenicity and 2-stage skin papillomagenesis studies conducted in benzopyrene-induced lung carcinogenesis and 7,12-dimethyl benz(a)anthracene-mediated skin papillomagenesis mouse models further validated our in vitro observations. This is the first demonstration of chemopreventive activities of papaya seed products, however, further studies to understand the subtle targets of intracellular signaling pathways, pharmacological profile and toxicological safety of this bioactive fraction are essential to pave the way for successful clinical translation. Our study supports the inverse association between dietary flavonoid intake and cancer risk.

Severity of hepatitis C virus (genotype-3) infection positively correlates with circulating microRNA-122 in patients sera

Introduction. Hepatitis C virus (genotype-3) causes acute and chronic hepatitis infection predomination in India. The infectious phase of the virus requires various host factors for its survival and subsequent viral particle production. Small RNA molecules like microRNA-122 (miR-122) are one such factor mostly present in the liver and play a supportive role in viral replication. Objective. In this study, diagnostic potential of miR-122 is evaluated in the sera of chronic hepatitis C patients. Methods. miRNAs were isolated from the sera samples of patients as well as controls and miR-122 expression was quantified by real-time PCR. Results. A significant augmentation was observed in the level of circulating miR-122 (median level, 0.66 versus 0.29, P = 0.001) in patients compared to controls with ROC value of 0.929 ± 0.034 (P < 0.001). Interestingly, miR-122 level also depicted a significant positive correlation with serum ALT (r = 0.53), AST (r = 0.44), and viral load (r = 0.52). Conclusion. The study thus unveiled the role of miR-122 as a plausible diagnostic biomarker during HCV genotype-3 infection in India.

Chronic hepatitis C treatment outcomes in low- and middle-income countries: a systematic review and meta-analysis

OBJECTIVE

To assess the effectiveness of treatment for hepatitis C virus (HCV) infection in low- and middle-income countries and identify factors associated with successful outcomes.

METHODS

We performed a systematic review and meta-analysis of studies of HCV treatment programmes in low- and middle-income countries. The primary outcome was a sustained virological response (SVR). Factors associated with treatment outcomes were identified by random-effects meta-regression analysis.

FINDINGS

The analysis involved data on 12 213 patients included in 93 studies from 17 countries. The overall SVR rate was 52% (95% confidence interval, CI: 48-56). For studies in which patients were predominantly infected with genotype 1 or 4 HCV, the pooled SVR rate was 49% (95% CI: 43-55). This was significantly lower than the rate of 59% (95% CI: 54-64) found in studies in which patients were predominantly infected with other genotypes (P = 0.012). Factors associated with successful outcomes included treatment with pegylated interferon and ribavirin, infection with an HCV genotype other than genotype 1 or 4 and the absence of liver damage or human immunodeficiency virus infection at baseline. No significant difference in the SVR rate was observed between weight-adjusted and fixed-dose ribavirin treatment. Overall, 17% (95% CI: 13-23) of adverse events resulted in treatment interruption or dose modification, but only 4% (95% CI: 3-5) resulted in treatment discontinuation.

CONCLUSION

The outcomes of treatment for HCV infection in low- and middle-income countries were similar to those reported in high-income countries.

Novel approach for quantification of hepatitis C virus in liver cirrhosis using real-time reverse transcriptase PCR

BACKGROUND

Hepatitis C virus (HCV) infects nearly 3% of the population worldwide and is a major cause of acute and chronic infections leading to fibrosis, cirrhosis, and hepatocellular carcinoma. Current laboratory diagnosis of HCV is based on specific antibody detection (anti-hepatitis C virus (anti-HCV)) in serum. As HCV replicates in the liver cells, detection and localization of HCV RNA in liver tissue are vital for diagnosis.

METHODS

Ten biopsy samples diagnosed for cryptogenic liver cirrhosis, negative for the presence of anti-HCV and serum HCV RNA, were studied for analyzing presence of viral nucleic acid in liver tissues. Qualitative screening for HCV was done through ELISA while the nucleic acid analysis was performed through COBAS Amplicor. Detection of HCV RNA in liver tissue biopsies was performed following standard protocol of HCV detection kit (Shenzhen PG Biotech) with modifications using Light Cycler 2.0 (minimum detection limit 10 copies/ml).

RESULT

Quantitative detection in liver biopsies following the modified method showed the presence of HCV RNA in three samples out of the ten studied.

CONCLUSION

The results indicate that using Light Cycler 2.0, following the modified technique described, constitutes a reliable method of quantitative detection and localization of HCV in tissue in "serosilent" HCV infection.

Occult hepatitis C virus elicits mitochondrial oxidative stress in lymphocytes and triggers PI3-kinase-mediated DNA damage response

Occult hepatitis C viral infection (OHCI) is a newly reported pathological entity associated with increased risk of developing hepatocellular carcinoma and lymphoproliferative disorders. Although hepatocytes are the primary sites of viral replication, hepatitis C virus is potentially lymphotropic, invading and propagating in cells of the immune system. Lymphocytes, the extrahepatic viral reservoirs, are differentially implicated in the occult and the active forms of the disease. This study aimed to elucidate the implications of mitochondrial oxidative stress on the immune pathophysiological mechanisms of OHCI. We herein report that OHCI induces mitochondrial oxidative stress, leading to DNA double-strand breaks and elicitation of a phosphoinositol 3-kinase-mediated cellular response in peripheral blood lymphocytes. Compared to controls, OHCI subjects showed higher accumulation of pATM, pATR, γH2AX, and p-p53, along with active recruitment of repair proteins (Mre11, Rad50, and Nbs1) and altered mitochondrial DNA content. Increased mitochondrial membrane depolarization and circulating nucleosome levels along with chromatid-type aberrations and decreased T-cell proliferative index observed in the OHCI group further indicated that this damage might lead to Bax-triggered mitochondria-mediated cellular apoptosis. Together our results provide the mechanistic underpinnings of mitochondrial dysfunction in OHCI, a previously unknown paradigm, for explaining the immune pathogenesis in a redox-dependent manner.

Circulating Biomarkers and their Possible Role in Pathogenesis of Chronic Hepatitis B and C Viral Infections

The present study evaluated the plausible role of circulating biomarkers in immune pathogenesis of chronic hepatitis considered a priority in clinical hepatology. Total viral load of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) patients was quantified and correlation studies were performed with circulating levels of Th1/Th2 cytokines; C reactive protein and circulating nucleosomes; glutathione reductase (GR) and superoxide dismutase. To our knowledge, the study is first among its kind that validates strong positive correlation of viral load with IL-4, IL-6, GR in HBV and IL-6, IL-10, GR in HCV infections. Although, multi-centric studies including large cohorts are required for translating our findings to clinical practice, however, role of these biomarkers with potential diagnostic or prognostic significance might be helpful in clinical assessment of high-risk individuals, thereby, designing interventional strategies, towards development of personalized medicare. The results of our study also offer valuable insights of immune signaling mediators engaged in development of hepatocellular carcinoma.

Molecular surveillance of hepatitis and tuberculosis infections in a cohort exposed to methyl isocyanate

OBJECTIVE

The potential toxic effects on the immune system exerted by occupational and accidental environmental exposures and underlying molecular regulatory mechanisms involved in the etiology and progression of infectious diseases are now being characterized. The Bhopal gas tragedy is undoubtedly one of the worst industrial disasters in the history of mankind. After 25 years of accidental exposure to methyl isocyanate (MIC), severe systemic ailments still continue to pre-occupy the lives of the affected population that survived this tragedy. We have performed a molecular surveillance study to characterize hepatitis and tuberculosis infections amongst the first and the second generation of survivors exposed to MIC.

MATERIALS AND METHODS

Both outdoor and indoor patients referred for molecular diagnosis of hepatitis B virus (HBV), hepatitis C virus (HCV) and Mycobacterium tuberculosis (MTB) were examined. Qualitative analysis for HBsAg, anti-HBc, anti-HCV through ELISA was performed, while BacT/ALERT and Ziehl-Neelson technique were utilized for the assessment of tuberculosis. Detection and quantification of viral and bacterial nucleic acid and characterization of hepatitis genotypes were analyzed using real-time and end-point PCR techniques.

RESULTS

The results suggest that HBV infections are most common among the MIC-exposed cohort, followed by extra-pulmonary and pulmonary MTB and HCV infections. Genotype 3 is the most prevalent HCV genotype among the survivors. Failure to detect HBsAg, anti-HBc and anti-HCV through ELISA, and tuberculosis by culture and Ziehl-Neelson stain, indicates higher prevalence of occult hepatitis and latent tuberculosis in the affected population.

CONCLUSIONS

Our study underscores the importance of hospital-based records used as a data source for monitoring possible environmental health hazards. As the risk of progress of infection is often influenced by conditions and periods of environmental chemical exposure, therefore, insights of interconnected molecular pathways will further illuminate the gene-environment association and might offer valuable information for rational drug design.