S. Osowska

The correlation between pretreatment cytokine expression patterns in peripheral blood mononuclear cells with chronic hepatitis c outcome

Cytokine response against hepatitis C virus (HCV) is likely to determine the natural course of infection as well as the outcome of antiviral treatment. However, the role of particular cytokines remains unclear. The current study analyzed activation of cytokine response in chronic hepatitis C patients undergoing standard antiviral treatment. Twenty-two patients were treated with pegylated interferon and ribavirin. Twenty-six different cytokine transcripts were measured quantitatively in peripheral blood mononuclear cells (PBMC) before and after therapy and correlated with therapy outcome as well as with clinical and liver histological data. We found that patients who achieved sustained virological response (SVR) showed higher pretreatment cytokine response when compared to subjects in whom therapy was unsuccessful. The differentially expressed factors included IL-8, IL-16, TNF-α, GM-CSF, MCP-2, TGF-β, and IP-10. Serum ALT activity and/or histological grading also positively correlated with the expression of IL-1α, IL-4, IL-6, IL-10, IL-12, IL-15, GM-CSF, M-CSF, MCP-2 and TGF-β. Pretreatment activation of the immune system, as reflected by cytokines transcripts upregulation, positively correlates with treatment outcome and closely reflects liver inflammatory activity.

Citrulline in health and disease. Review on human studies

The amino acid L-citrulline (CIT) is safely used from the neonatal period onwards in those with urea cycle defects and carbamyl phosphate synthetase or ornithine transcarbamylase deficiencies, but several lines of enquiry indicate that it might have a much wider therapeutic role. When protein intake is low and there is a catabolic state, endogenous arginine (ARG) synthesis cannot fully be met and its supplementation can prove challenging, particularly in patients with critical and multisystem illness. Supplementary CIT could constitute a safer but still focused means of delivering ARG to endothelial and immune cells as CIT is efficiently recycled into these cells and as kidneys can convert CIT into ARG. Unlike ARG, CIT is efficiently transported into enterocytes and bypasses liver uptake. It also appears to prevent excessive and uncontrolled nitric oxide (NO) production. Animal studies and early human data indicate positive effects of CIT on protein synthesis, in which its contribution is thought mediated through the mTOR pathway. It appears that CIT is an anabolic pharmaconutrient that can be safely administered even in critically ill patients. Promising results in cardiovascular diseases and in disease-related malnutrition can now be considered sufficient to justify formal clinical exploration in these areas and in sarcopenia in general.