Hepcidin: Homeostasis and Diseases Related to Iron Metabolism.

Iron is an essential metal for cell survival that is regulated by the peptide hormone hepcidin. However, its influence on certain diseases is directly related to iron metabolism or secondary to underlying diseases. Genetic alterations influence the serum hepcidin concentration, which can lead to an iron overload in tissues, as observed in haemochromatosis, in which serum hepcidin or defective hepcidin synthesis is observed. Another genetic imbalance of iron is iron-refractory anaemia, in which serum concentrations of hepcidin are increased, precluding the flow and efflux of extra- and intracellular iron. During the pathogenesis of certain diseases, the resulting oxidative stress, as well as the increase in inflammatory cytokines, influences the transcription of the HAMP gene to generate a secondary anaemia due to the increase in the serum concentration of hepcidin. To date, there is no available drug to inhibit or enhance hepcidin transcription, mostly due to the cytotoxicity described in the in vitro models. The proposed therapeutic targets are still in the early stages of clinical trials. Some candidates are promising, such as heparin derivatives and minihepcidins. This review describes the main pathways of systemic and genetic regulation of hepcidin, as well as its influence on the disorders related to iron metabolism.

Hepatitis C worldwide and in Brazil: silent epidemic--data on disease including incidence, transmission, prevention, and treatment.

Hepatitis C virus (HCV) is endemic worldwide and according to the World Health Organization (WHO), there are about 150 million chronic carriers worldwide. The infection is a leading cause of liver diseases like cirrhosis and hepatocellular carcinoma (HCC); thus, HCV infection constitutes a critical public health problem. There are increasing efforts worldwide in order to reduce the global impact of hepatitis C through the implementation of programmatic actions that may increase the awareness of viral hepatitis and also improve surveillance, prevention, and treatment. In Brazil, about 1,5 million people have been chronically infected with HCV. The country has a vast territory with uneven population density, and hepatitis C incidence rates are variable with the majority of cases concentrated in the most populated areas. Currently, the main priorities of Brazilian Ministry of Health's strategies for viral hepatitis management include the prevention and early diagnosis of viral hepatitis infections; strengthening of the healthcare network and lines of treatment for sexually transmitted diseases, viral hepatitis, and AIDS; improvement and development of surveillance, information, and research; and promotion of universal access to medication. This review aims to summarize the available data on hepatitis C epidemiology and current status of efforts in prevention and infection control around the world and in Brazil.

Serum levels of IgG antibodies against oxidized LDL and atherogenic indices in HIV-1-infected patients treated with protease inhibitors.

BACKGROUND: Antibodies against low-density lipoproteins (LDLs) that have been oxidized are associated with development of atherosclerotic lesions. In individuals infected with human immunodeficiency virus type 1 (HIV-1) with or without therapy, dyslipidemia and increased cardiovascular risk are observed. METHODS: Serum levels of IgG antibodies against oxidized LDLs (IgG anti-oxLDL Abs) were determined by assay in 151 HIV-1-infected patients. Of these, 42 patients did not receive anti-retroviral therapy (ART-naïve), whereas 109 received highly active anti-retroviral therapy (HAART) consisting of lopinavir/ritonavir (LOP/r; n=50), efavirenz (EFV; n=30) and nevirapine (NVP; n=29) associated with nucleoside reverse transcriptase inhibitors. HIV-1 seronegative individuals (n=43) participated in the study. The following parameters were quantified: total cholesterol and its fractions, atherogenic indices (AIs), apolipoproteins A1 and B100, high sensitivity C-reactive protein, CD4+ and CD8+ T cells, and HIV-1-RNA. RESULTS: Levels of IgG anti-oxLDL Abs were significantly higher (p<0.05) in the LOP/r group compared with the EFV and/or NVP and the seronegative group: median 0.32 (0.15, 0.58; 95% confidence interval) vs. 0.25 (0.13, 0.53) vs. 0.18 (0.04, 0.38), respectively. HIV-1-infected ART-naïve patients (n=42) presented antibodies levels similar to those observed for the LOP/r group, 0.33 (0.13, 0.63; p>0.05). The levels of IgG anti-oxLDL Abs correlated with an increase in AIs (r=0.216; p=0.036) and triglycerides (r=0.220; p=0.044) in the LOP/r group, and AIs in the ART-naïve group (r=0.300; p=0.046). CONCLUSIONS: Patients treated with LOP/r showed higher levels of IgG anti-oxLDL Abs compared with patients treated with EFV or NVP regimens, and these levels were associated with an increase in AIs.

Impact of antiretroviral therapy on lipid metabolism of human immunodeficiency virus-infected patients: Old and new drugs.

For human immunodeficiency virus (HIV)-infected patients, the 1990s were marked by the introduction of highly active antiretroviral therapy (HAART) representing a new perspective of life for these patients. The use of HAART was shown to effectively suppress the replication of HIV-1 and dramatically reduce mortality and morbidity, which led to a better and longer quality of life for HIV-1-infected patients. Apart from the substantial benefits that result from the use of various HAART regimens, laboratory and clinical experience has shown that HAART can induce severe and considerable adverse effects related to metabolic complications of lipid metabolism, characterized by signs of lipodystrophy, insulin resistance, central adiposity, dyslipidemia, increased risk of cardiovascular disease and even an increased risk of atherosclerosis. New drugs are being studied, new therapeutic strategies are being implemented, and the use of statins, fibrates, and inhibitors of intestinal cholesterol absorption have been effective alternatives. Changes in diet and lifestyle have also shown satisfactory results.

Human paraoxonase-1 activity is related to the number of CD4+ T-cells and is restored by antiretroviral therapy in HIV-1-infected individuals.

BACKGROUND: Paraoxonase-1 (PON1) activity is suggested to be altered in individuals infected with human immunodeficiency virus type-1 (HIV-1). We investigated PON1 activity in individuals receiving different regimens of highly active antiretroviral therapy (HAART). METHODS: PON1 activity was evaluated in 91 HIV-1 seronegative and 624 HIV-1 infected individuals (115 were not undergoing therapy (ART-naïve), and 509 were receiving HAART). HIV-1 infected individuals were treated with the following: efavirenz (EFV; n = 195) or nevirapine (NVP; n = 95) or lopinavir/ritonavir (LOP/r; n = 219). Serum levels of total cholesterol (TC), HDL, and low-density lipoprotein (LDL) fractions and the atherogenic indices (AI, TC : HDL, and LDL : HDL ratios) were determined. RESULTS: PON1 activity (U/L) was lower in the ART-naïve group compared with the other groups. PON1 activity correlated with CD4+ T-cell number of ART-naïve group (r = 0,121; P = 0,014). The LOP/r group showed a reduction in HDL and an increase in AI (TC : HDL ratio) in comparison with other groups. CONCLUSION: PON1 activity was reduced in untreated individuals, but not in individuals receiving HAART. PON1 activity correlated with the number of CD4+ T-cells. The findings suggest that the activity of PON1 is associated with the immune status of HIV-1 infected individuals.