Role of Influenza A virus protein NS1 in regulating host nuclear body ND10 complex formation and its involvement in establishment of viral pathogenesis.

Influenza viral infection is a seasonal infection which causes widespread acute respiratory issues among humans globally. This virus changes its surface receptor composition to escape the recognition process by the host's immune cells. Therefore, the present study focussed to identify some other important viral proteins which have a significant role in establishment of infection and having apparent conserved structural composition. This could facilitate the permanent vaccine development process or help in designing a drug against IAV (influenza A virus) infection which will eliminate the seasonal flu shot vaccination process. The NS1 (Non-structural protein 1) protein of IAV maintains a conserved structural motif. Earlier studies have shown its significant role in infection establishment. However, the mechanism by which viruses escape the host's ND10 antiviral action remains elusive. The present study clearly showed that IAV infection and NS1 transfection in A549 cells degraded the main component of the ND10 anti-viral complex, PML and therefore, inhibited the formation of Daxx-sp100-p53-PML complex (ND10) at the mid phase of infection/transfection. PML degradation activated the stress axis which increased cellular ROS (reactive oxygen species) levels as well as mitochondrial dysfunction. Additionally, IAV/NS1 increased cellular stress and p53 accumulation at the late phase of infection. These collectively activated apoptotic pathway in the host cells. Along with the inactivation of several interferon proteins, IAV was found to decrease p-IKKε. A549 cells transfected with pcDNA3.1-NS1 showed a similar effect in the interferon axis and IKKε. Moreover, NS1 induced the disintegration of the host's ND10 complex through the changes in the SUMOylation pattern of the PML nuclear body. These findings suggest the possible mechanism of how NS1 helps IAV to establish infection in the host cells. However, it demands further detailed study before targeting NS1 to develop permanent vaccines or novel drugs against IAV in future.

Enhanced inflammasome-mediated inflammation and impaired autophagy in peripheral blood mononuclear cells is associated with non-alcoholic fatty liver disease severity.

AIMS: Identification of the progress of non-alcoholic fatty liver disease (NAFLD) is crucial for their effective treatment. Circulating peripheral blood mononuclear cells (PBMC) could be a surrogate monitor instead of complicated and expensive biopsies. Changes in immuno-metabolic status in NAFLD patients may be reflected by an expression of different PBMC-specific molecular markers. It was hypothesized that impaired autophagy with enhanced inflammasome activation is a critical molecular event in PBMC that could contribute to systemic inflammation associated with NAFLD progression. MAIN METHODS: A cross-sectional study with a sample size of 50 subjects were undertaken from a governmental facility in Kolkata, India. Major anthropometric, biochemical, and dietary parameters were recorded. Cellular and serum samples of NAFLD patients were analyzed for oxidative stress, inflammation, inflammasome activation, and autophagic flux by western blot, flow cytometry, immunocytochemistry. KEY FINDINGS: Baseline anthropometric and clinical parameters were found associated with NAFLD severity. Elevated systemic inflammation was reflected by higher proinflammatory markers like iNOS, Cox-2, IL-6, TNF-α, IL-1ß, hsCRP in the serum of NAFLD subjects (p < 0.05). ROS-induced NLRP3 inflammasomes marker proteins were upregulated (p < 0.05) in PBMC along with NAFLD severity. Expression of autophagic markers such as LC3B, Beclin-1 and its regulator pAMPKα were found diminished (p < 0.05) with a concomitant rise of p62. Colocalization of NLRP3 with LC3B proteins in PBMC was found diminished along NAFLD severity. SIGNIFICANCE: Present data provide mechanistic evidence of impaired autophagy and intracellular ROS triggered inflammasome activation in PBMC, which could potentially exacerbate NAFLD severity.

Ferulic acid enhances the radiation sensitivity of lung and liver carcinoma cells by collapsing redox homeostasis: mechanistic involvement of Akt/p38 MAPK signalling pathway.

The major drawback of anticancer therapy is the development of resistance against drugs and radiation at the later phase of treatment which may lead to recurrences of the disease. Therefore, strategy was taken to enhance radiation sensitivity of lung (A549) and liver (HepG2) carcinoma cells by treatment with ferulic acid (FA) prior to irradiation. FA pre-treatment initially decreased reactive oxygen species (ROS) level in carcinoma cells which induced reductive stress and cytostasis. To overcome this stress, cellular mechanism increased the Keap1 level to down-regulate nuclear localisation of Nrf2 and its dependent antioxidant system. The antioxidant system reached the lowest level after 3 and 6 h of FA treatment in A549 and HepG2 cells respectively. As endogenous ROS were still being generated at same rate, ROS level was clearly higher than control which changed the reductive stress to oxidative stress. Exposure to γ-radiation in this condition further increased ROS level and caused radio-sensitisation of carcinoma cells. Combination of irradiation (IR) and FA activated mitochondrial apoptotic pathway and concomitantly inhibited the cell cycle progression and survival pathway over the IR group. Moreover, the combination treatment showed significant tumour regression, caspase 3 activation and nuclear fragmentation in tumour tissue compared to radiation alone. In contrast, FA pre-treatment protected peripheral blood mononuclear cells (PBMC) and normal lung fibroblast WI38 cells from radiation damage. Together, combination treatment offers effective strategy of killing cancer cells and demonstrates its potential for increasing the efficacy of radio-therapy.

An association study of severity of intellectual disability with peripheral biomarkers of disabled children in a rehabilitation home, Kolkata, India.

The current investigation has identified the biomarkers associated with severity of disability and correlation among plethora of systemic, cellular and molecular parameters of intellectual disability (ID) in a rehabilitation home. The background of study lies with the recent clinical evidences which identified complications in ID. Various indicators from blood and peripheral system serve as potential surrogates for disability related changes in brain functions. ID subjects (Male, age 10 ± 5 yrs, N = 45) were classified as mild, moderate and severe according to the severity of disability using standard psychometric analysis. Clinical parameters including stress biomarkers, neurotransmitters, RBC morphology, expressions of inflammatory proteins and neurotrophic factor were estimated from PBMC, RBC and serum. The lipid peroxidation of PBMC and RBC membranes, levels of serum glutamate, serotonin, homocysteine, ROS, lactate and LDH-A expression increased significantly with severity of ID whereas changes in RBC membrane ß-actin, serum BDNF, TNF-α and IL-6 was found non-significant. Structural abnormalities of RBC were more in severely disabled children compared to mildly affected ones. The oxidative stress remained a crucial factor with severity of disability. This is confirmed not only by RBC alterations but also with other cellular dysregulations. The present article extends unique insights of how severity of disability is correlated with various clinical, cellular and molecular markers of blood. This unique study primarily focuses on the strong predictors of severity of disability and their associations via brain-blood axis.