HOST GENETIC VARIANTS, TREATMENT OUTCOMES AND METABOLIC COMPLICATIONS IN HEPATITIS C VIRUS GENOTYPE-1

Chronic Hepatitis C Virus (HCV) infection is prevalent in approximately 3.2 million people in the United States. Understanding mechanisms of HCV treatment response and conditions seen in people with HCV such as steatosis and Insulin Resistance (IR) are important to preventing excess morbidity and mortality and improving HCV treatment outcomes. Host genetic factors may be important with respect to these issues. The purpose of this research was to investigate host genetic relationships with 28 day viral decline after treatment initiation, steatosis and insulin resistance and to examine these associations separately in African Americans and Caucasian Americans infected with HCV genotype-1. Data from the Study of Viral Resistance of Antiviral Therapy of Chronic Hepatitis C (Virahep-C) were used. Virahep-C was designed to understand the mechanisms of resistance to antiviral therapy for chronic HCV genotype-1 patients. The studies reported in this dissertation included up to 194 Caucasian Americans (CA) and 180 African Americans (AA) who agreed to participate in the Virahep-C genetics ancillary study. In longitudinal analyses of 28 day treatment induced viral decline, polymorphisms in Myxovirus resistance 2 (MX2), Oligoadenylate synthetase-like (OASL), Signal transducer and activator of transcription 1 and 2 (STAT1 and STAT2) were significantly associated with viral decline. Additionally, significant Protein Kinase (PKR) haplotype associations with viral decline were observed among AAs. In cross-sectional analyses, significant associations between selected genetic variants and either steatosis or IR were observed in Interleukin-10 (IL10), Leptin Receptor (LEPR), Interleukin-6 (IL6) and Transforming Growth Factor Beta 1 (TGF-â1) for both conditions. Statistically significant interactions were observed between IL10, LEPR and TGF-â1 polymorphisms and HOMA2-IR scores when examining steatosis.Statistically significant associations were observed for Adiponectin Receptor 1 (ADIPOR1) polymorphisms and 3-hydroxy-3-methylglutaryl-Coenzyme A synthase 2 (HMGCS2) polymorphisms and steatosis or IR. Overall, these findings suggest that host genetic factors are associated with treatment induced 28 day viral decline, steatosis and IR. Understanding the biological mechanisms that contribute to these findings has significant public health implications because it could help establish new therapies and interventions to prevent HCV related morbidity and mortality. Results may also contribute to understanding the mechanisms of treatment response, steatosis and IR

Up-regulation of prostaglandin biosynthesis by leukotriene C4 in elicited mice peritoneal macrophages activated with lipopolysaccharide/interferon-gamma

Leukotrienes (LT) and prostaglandins (PG) are proinflammatory mediators generated by the conversion of arachidonic acid via 5-lipoxygenase (5-LO) and cyclooxygenase (COX) pathways. It has long been proposed that the inhibition of the 5-LO could enhance the COX pathway leading to an increased PG generation. We have found that in in vitro models of inflammation, such as mice-elicited peritoneal macrophages activated with lipopolysaccharide (LPS)/interferon- γ (IFN-γ), the deletion of the gene encoding for 5-LO or the enzyme activity inhibition corresponded to a negative modulation of the COX pathway. Moreover, exogenously added LTC4, but not LTD4, LTE 4, and LTB4, was able to increase PG production in stimulated cells from 5-LO wild-type and knockout mice. LTC4 was not able to induce COX-2 expression by itself but rather potentiated the action of LPS/IFN-γ through the extracellular signal-regulated kinase-1/2 activation, as demonstrated by the use of a specific mitogen-activated protein kinase (MAPK) kinase inhibitor. The LT-induced increase in PG generation, as well as MAPK activation, was dependent by a specific ligand-receptor interaction, as demonstrated by the use of a cys-LT1 receptor antagonist, although also a direct action of the antagonist used, on PG generation, cannot be excluded. Thus, the balance between COX and 5-LO metabolites could be of great importance in controlling macrophage functions and consequently, inflammation and tumor promotion

Are the Follicular Fluid Characteristics of Recovered Coronavirus Disease 2019 Patients Different From Those of Vaccinated Women Approaching in vitro Fertilization?

The aim of this pilot study is to evaluate if SARS-CoV-2 infection or vaccination against SARS-CoV-2 infection induce observable metabolic effects in follicular fluid of women who are following in vitro fertilization (IVF) treatments. The possible impact of coronavirus disease 2019 (COVID-19) on fertility and IVF outcome is considered. We have selected for this study: six women vaccinated against SARS-CoV-2 infection, five recovered COVID-19 patients, and we used nine healthy women as the control group. At the time of oocytes retrieval from participants in the study, follicular fluids were collected and metabolomic analysis was performed by 1H NMR spectroscopy in combination with multivariate analysis to interpret the spectral data. The search for antibody positivity in the follicular fluid aspirates was also carried out, together with the western blotting analysis of some inflammatory proteins, interleukin-6, tumor necrosis factor α (TNFα), and the free radical scavenger superoxide dismutase 2. Higher levels of Ala and Pro together with lower levels of lipids and trimethylamine N-oxide (TMAO) were found in follicular fluids (FFs) of vaccinated women while lower levels of many metabolites were detected in FFs of recovered COVID patients. Expression level of TNF-α was significantly lower both in recovered COVID-19 patients and vaccinated women in comparison to healthy controls

The receptor-type protein tyrosine phosphatase J antagonizes the biochemical and biological effects of RET-derived oncoproteins.

Abstract Thyroid cancer is frequently associated with the oncogenic conversion of the RET receptor tyrosine kinase. RET gene rearrangements, which lead to the generation of chimeric RET/papillary thyroid carcinoma (PTC) oncogenes, occur in PTC, whereas RET point mutations occur in familial multiple endocrine neoplasia type 2 (MEN2) and sporadic medullary thyroid carcinomas (MTC). We showed previously that the expression of the receptor-type protein tyrosine phosphatase J (PTPRJ) is suppressed in neoplastically transformed follicular thyroid cells. We now report that PTPRJ coimmunoprecipitates with wild-type RET and with the MEN2A-associated RET(C634R) oncoprotein but not with the RET/PTC1 and RET-MEN2B isoforms. Using mutated forms of PTPRJ and RET-MEN2A, we show that the integrity of the respective catalytic domains is required for the PTPRJ/RET-MEN2A interaction. PTPRJ expression induces dephosphorylation of the RET(C634R) and, probably via an indirect mechanism, RET/PTC1 oncoproteins on two key RET autophosphorylation sites (Tyr1062 and Tyr905). This results in a significant decrease of RET-induced Shc and extracellular signal-regulated kinase 1/2 phosphorylation levels. In line with this finding, adoptive PTPRJ expression reduced the oncogenic activity of RET(C634R) in an in vitro focus formation assay of NIH3T3 cells. As expected from the coimmunoprecipitation results, the RET(M918T) oncoprotein, which is associated to MEN2B and sporadic MTC, was resistant to the dephosphorylating activity of PTPRJ. Taken together, these findings identify RET as a novel substrate of PTPRJ and suggest that PTPRJ expression levels may affect tumor phenotype associated with RET/PTC1 and RET(C634R) mutants. On the other hand, resistance to PTPRJ may be part of the mechanism of RET oncogenic conversion secondary to the M918T mutation. (Cancer Res 2006; 66(12): 6280-7

60kDa Lysophospholipase, a New Sgk1 Molecular Partner Involved in the Regulation of ENaC

The serum- and glucocorticoid-regulated kinase (Sgk1) is essential for hormonal regulation of ENaC-mediated sodium transport and is involved in the transduction of growth-factor-dependent cell survival and proliferation. The identification of molecular partners for Sgk1 is crucial for the understanding of its mechanisms of action. We performed a yeast two-hybrid screening based on a human kidney cDNA library to identify molecular partners of Sgk1. As a result the screening revealed a specific interaction between Sgk1 and a 60 kDa Lysophospholipase (LysoLP). LysoLP is a poorly characterized enzyme that, based on sequence analysis, might possess lysophospholipase and asparaginase activities. We demonstrate that LysoLP has indeed a lysophospholipase activity and affects metabolic functions related to cell proliferation and regulation of membrane channels. Moreover we demonstrate in the Xenopus oocyte expression system that LysoLP downregulates basal and Sgk1-dependent ENaC activity. In conclusion LysoLP may represent a new player in the regulation of ENaC and Sgk1-dependent signaling

War journalism: an occupational exposure

Apart from the risk of accidents, war theatres present a hazard related to numerous long-lasting toxic agents. For 10 years, a >60-year-old male journalist worked in war theatres in the Far and Near East where he was exposed to asbestos and other toxic substances (metals, silica, clays, polycyclic aromatic hydrocarbons and other organic substances) contained in dust and smoke of destroyed buildings. More than 15 years later, he developed a mucoepidermoid carcinoma of the soft palate and, subsequently, a pleural malignant mesothelioma. The safety of war journalists should focus not only on preventing the risk of being killed, but also on providing protection from toxic and carcinogenic agents. Exposure to substances released during the destruction of buildings can also pose a carcinogenic risk for survivors

All-cause versus cause-specific excess deaths for estimating influenza-associated mortality in Denmark, Spain, and the United States

Background: Seasonal influenza-associated excess mortality estimates can be timely and provide useful information on the severity of an epidemic. This methodology can be leveraged during an emergency response or pandemic. Method: For Denmark, Spain, and the United States, we estimated age-stratified excess mortality for (i) all-cause, (ii) respiratory and circulatory, (iii) circulatory, (iv) respiratory, and (v) pneumonia, and influenza causes of death for the 2015/2016 and 2016/2017 influenza seasons. We quantified differences between the countries and seasonal excess mortality estimates and the death categories. We used a time-series linear regression model accounting for time and seasonal trends using mortality data from 2010 through 2017. Results: The respective periods of weekly excess mortality for all-cause and cause-specific deaths were similar in their chronological patterns. Seasonal all-cause excess mortality rates for the 2015/2016 and 2016/2017 influenza seasons were 4.7 (3.3-6.1) and 14.3 (13.0-15.6) per 100,000 population, for the United States; 20.3 (15.8-25.0) and 24.0 (19.3-28.7) per 100,000 population for Denmark; and 22.9 (18.9-26.9) and 52.9 (49.1-56.8) per 100,000 population for Spain. Seasonal respiratory and circulatory excess mortality estimates were two to three times lower than the all-cause estimates. Discussion: We observed fewer influenza-associated deaths when we examined cause-specific death categories compared with all-cause deaths and observed the same trends in peaks in deaths with all death causes. Because all-cause deaths are more available, these models can be used to monitor virus activity in near real time. This approach may contribute to the development of timely mortality monitoring systems during public health emergencies.This study was conducted as part of Sebastian Schmidt's research fellowship, which was financially supported by the Novo Nordic Foundation and A.P. Møller Fonden. The EuroMOMO network has received financial support from the European Centre for Disease Prevention and Control (ECDC) and from the World Health Organization (WHO) Regional Office for Europe.S

Relationship between serum bilirubin and uric acid to oxidative stress markers in Italian and Czech populations

Summary Recently, a South-to-North oxidative stress marker gradient has been reported; consistent with known differences in the incidence of coronary heart disease between southern and northern European countries. The aim of the present study was to compare the plasma concentrations of 7-oxocholesterol (7OxCH) and 7β-hydroxycholesterol (7BCH) with systemic antioxidants in healthy Italian and Czech subjects. The study was performed in healthy subjects of Italian (n=131) and Czech (n=84) origins. In all subjects routine biochemistry work-ups were performed; additionally, plasma oxysterols and the peroxyl radicals scavenging activity (PERSA) of the sera were determined. Close relationship of serum bilirubin and uric acid to markers of oxidative stress was observed in both examined populations. Compared to the Czechs, the Italian population showed higher plasma concentrations of both oxysterols (7OxCH: 3.6 vs. 6.0 ng/ml, p −6 ; 7BCH: 5.3 vs. 8.6 ng/ml, p −6 ), lower PERSA (p −6 ), and lower serum concentrations of bilirubin and uric acid (p −6 in both cases). The dietary patterns of the Italian population did not match the Mediterranean style, but was more similar to the Continental type of diet, presumably due to non-adherence to a Mediterranean diet