Specific Plasma MicroRNA Signatures Underlying the Clinical Outcomes of Hepatitis E Virus Infection

The pathogenic mechanisms determining the diverse clinical outcomes of HEV infection (e.g., self-limiting vs chronic or symptomatic vs asymptomatic) are not yet understood. Because specific microRNA signatures during viral infection inform the cellular processes involved in virus replication and pathogenesis, we investigated plasma microRNA profiles in 44 subjects, including patients with symptomatic acute (AHE, n = 7) and chronic (CHE, n = 6) hepatitis E, blood donors with asymptomatic infection (HEV BDs, n = 9), and anti-HEV IgG+IgM- (exposed BDs, n = 10) and anti-HEV IgG-IgM- (naïve BDs, n = 12) healthy blood donors. By measuring the abundance of 179 microRNAs in AHE and naïve BDs by RT-qPCR, we identified 51 potencial HEV-regulated microRNAs (PBH < 0.05). Further analysis showed that HEV genotype 3 infection is associated with miR-122, miR-194, miR-885, and miR-30a upregulation and miR-221, miR-223, and miR-27a downregulation. AHE showed significantly higher levels of miR-122 and miR-194, and lower levels of miR-221, miR-27a, and miR-335 compared to HEV BDs. This specific microRNA signature in AHE could promote virus replication and reduce antiviral immune responses, contributing to the development of clinical symptoms. We found that mir-194, miR-335, and miR-221 can discriminate between asymptomatic HEV infections and those developing acute symptoms, whereas miR-335 correctly classify AHE and CHE. Conclusions: Our data suggest that diverse outcomes of HEV infection result from different HEV-induced microRNA dysregulations. The specific microRNA signatures described offer novel information that may serve to develop biomarkers of HEV infection outcomes and improve our understanding of HEV pathogenesis, which may facilitate the identification of antiviral targets

Fine-Tuning Translation Kinetics Selection as the Driving Force of Codon Usage Bias in the Hepatitis A Virus Capsid

Hepatitis A virus (HAV), the prototype of genus Hepatovirus, has several unique biological characteristics that distinguish it from other members of the Picornaviridae family. Among these, the need for an intact eIF4G factor for the initiation of translation results in an inability to shut down host protein synthesis by a mechanism similar to that of other picornaviruses. Consequently, HAV must inefficiently compete for the cellular translational machinery and this may explain its poor growth in cell culture. In this context of virus/cell competition, HAV has strategically adopted a naturally highly deoptimized codon usage with respect to that of its cellular host. With the aim to optimize its codon usage the virus was adapted to propagate in cells with impaired protein synthesis, in order to make tRNA pools more available for the virus. A significant loss of fitness was the immediate response to the adaptation process that was, however, later on recovered and more associated to a re-deoptimization rather than to an optimization of the codon usage specifically in the capsid coding region. These results exclude translation selection and instead suggest fine-tuning translation kinetics selection as the underlying mechanism of the codon usage bias in this specific genome region. Additionally, the results provide clear evidence of the Red Queen dynamics of evolution since the virus has very much evolved to re-adapt its codon usage to the environmental cellular changing conditions in order to recover the original fitness

Analysis of synonymous codon usage in Hepatitis A virus

<p>Abstract</p> <p>Background</p> <p>Hepatitis A virus is the causative agent of type A viral hepatitis, which causes occasional acute hepatitis. Nevertheless, little information about synonymous codon usage pattern of HAV genome in the process of its evolution is available. In this study, the key genetic determinants of codon usage in HAV were examined.</p> <p>Results</p> <p>The overall extent of codon usage bias in HAV is high in <it>Picornaviridae</it>. And the patterns of synonymous codon usage are quite different in HAV genomes from different location. The base composition is closely correlated with codon usage bias. Furthermore, the most important determinant that results in such a high codon bias in HAV is mutation pressure rather than natural selection.</p> <p>Conclusions</p> <p>HAV presents a higher codon usage bias than other members of <it>Picornaviridae</it>. Compositional constraint is a significant element that influences the variation of synonymous codon usage in HAV genome. Besides, mutation pressure is supposed to be the major factor shaping the hyperendemic codon usage pattern of HAV.</p

Isotemporal substitution of inactive time with physical activity and time in bed: Cross-sectional associations with cardiometabolic health in the PREDIMED-Plus study

© 2019 The Author(s). Background: This study explored the association between inactive time and measures of adiposity, clinical parameters, obesity, type 2 diabetes and metabolic syndrome components. It further examined the impact of reallocating inactive time to time in bed, light physical activity (LPA) or moderate-To-vigorous physical activity (MVPA) on cardio-metabolic risk factors, including measures of adiposity and body composition, biochemical parameters and blood pressure in older adults. Methods: This is a cross-sectional analysis of baseline data from 2189 Caucasian men and women (age 55-75 years, BMI 27-40 Kg/m2) from the PREDIMED-Plus study (http://www.predimedplus.com/). All participants had ≥3 components of the metabolic syndrome. Inactive time, physical activity and time in bed were objectively determined using triaxial accelerometers GENEActiv during 7 days (ActivInsights Ltd., Kimbolton, United Kingdom). Multiple adjusted linear and logistic regression models were used. Isotemporal substitution regression modelling was performed to assess the relationship of replacing the amount of time spent in one activity for another, on each outcome, including measures of adiposity and body composition, biochemical parameters and blood pressure in older adults. Results: Inactive time was associated with indicators of obesity and the metabolic syndrome. Reallocating 30 min per day of inactive time to 30 min per day of time in bed was associated with lower BMI, waist circumference and glycated hemoglobin (HbA1c) (all p-values < 0.05). Reallocating 30 min per day of inactive time with 30 min per day of LPA or MVPA was associated with lower BMI, waist circumference, total fat, visceral adipose tissue, HbA1c, glucose, triglycerides, and higher body muscle mass and HDL cholesterol (all p-values < 0.05). Conclusions: Inactive time was associated with a poor cardio-metabolic profile. Isotemporal substitution of inactive time with MVPA and LPA or time in bed could have beneficial impact on cardio-metabolic health. Trial registration: The trial was registered at the International Standard Randomized Controlled Trial (ISRCTN: http://www.isrctn.com/ISRCTN89898870) with number 89898870 and registration date of 24 July 2014, retrospectively registered

Waterborne gastroenteritis outbreak in Albania

Three different studies are reported concerning the environmental pollution caused by viruses in Albania. The first study describes an outbreak of gastroenteritis in the capital city, involving 2,722 children attending the Paediatric Unit of Tirana Hospital. The age group with the highest morbidity was 0-5 years, with 89.5%; no fatalities were recorded during the outbreak. Rotavirus was detected in 26/28 faecal samples by RT-PCR, although astrovirus, adenovirus and calicivirus were also present. The second study describes an outbreak of hepatitis A virus involving the city of Lac. Two hundred cases were recorded, with the highest incidence in the age-group 5-9 years. Phylogenetic analysis of the VP1/2A region showed the presence of a unique sequence: genotype IA. Rotavirus was identified in drinking-water samples collected during the outbreak. The third study describes the prevalence of HAV and HEV in 202 sera randomly collected from 12 different cities in Albania. HAV showed a high incidence (66.2%), whereas none was positive for HEV. The genomic analysis of the VP1/2A junction revealed the presence of only one genotype (IA) with few point mutations and just two amino acid substitutions at codons 22 and 34. Additionally, two potential antigenic variants were detected, the first at position 46 of VP3 and the second at position 23 of VP1