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Introduction: MicroRNAs (miRNAs) play a critical role in orchestrating T cell differentiation and activation and may thus play a vital role in acquired aplastic anemia (aAA). The study aimed to evaluate the differential expression of selected miRNAs and their relevant target genes in bone marrow samples of aAA patients. Methods: Differential expression of 8 miRNAs viz; hsa‐miR‐126‐3p, miR‐145‐5p, miR‐155‐5p, miR‐150‐5p, miR‐146b‐5p, miR‐34a, miR‐29a, and miR‐29b was evaluated in the bone marrow mononuclear cells of aAA patients. TaqMan microRNA assay was performed for preparing the cDNA of specific miRNA, followed by expression analysis using qRT‐PCR. Data were normalized using two endogenous controls, RNU6B and RNU48. Delta‐delta CT method was used to calculate the fold change (FC) of miRNA expression in individual samples, and a FC of >1.5 was taken as significant. Target genes of these miRNAs were evaluated by qRT‐PCR. Results: Thirty five samples of aAA patients and 20 controls were evaluated. Irrespective of the disease severity, five miRNAs were found to be deregulated; miR‐126 (FC‐0.348; P‐value‐.0001) and miR‐145 (FC‐0.31; P‐value‐.0001) were downregulated, while miR‐155 (FC‐3.50; P‐value‐.0067), miR‐146 (FC‐3.13; P‐value‐.0105), and miR‐150 (FC‐5.78; P‐value‐.0001) were upregulated. Target gene study revealed an upregulation of PIK3R2, MYC, SOCS1, and TRAF‐6, and downregulation of MYB. Conclusion: This is the first study from the Indian subcontinent demonstrating the presence of altered miRNA expression in the bone marrow samples of aAA patients, suggesting their role in the pathogenesis of the disease. A comprehensive study focusing on the effect of these miRNA‐mRNA interactions is likely to open new avenues of management. [ABSTRACT FROM AUTHOR]

Mesenchymal stromal cells (MSC) regulate hematopoiesis in the bone marrow (BM) niche and extracellular vesicles (EVs) released by BM‐MSC are important mediators of the cross‐talk between BM‐MSC and hematopoietic stem and progenitor cells (HSPC). We have previously demonstrated that BM‐MSC of severe aplastic anemia (SAA) patients have an altered expression of hematopoiesis regulatory molecules. In the present study, we observed that CD34+ HSPC when cocultured with BM‐MSC EVs from aplastic anemia patients exhibited a significant reduction in colony‐forming units (p =.001), cell proliferation (p =.002), and increased apoptosis (p >.001) when compared to coculture with BM‐MSC EVs from controls. Collectively, our results highlight that EVs derived from the BM‐MSC of SAA patients impair the hematopoiesis supporting function of HSPC. [ABSTRACT FROM AUTHOR]

Background: Altered T‐cell repertoire with an aberrant T‐cell activation and imbalance of the Th17/Treg cells has been reported in acquired aplastic anemia (aAA). miRNAs are well known to orchestrate T‐cell activation and differentiation, however, their role in aAA is poorly characterized. The study aimed at identifying the profile of miRNAs likely to be involved in T‐cell activation and the Th17/Treg‐cell imbalance in aAA, to explore newer therapeutic targets. Methods: Five milliliters peripheral blood samples from 30 patients of aAA and 15 healthy controls were subjected to flow cytometry for evaluating Th17‐ and Treg‐cell subsets. The differential expression of 7 selected miRNAs viz; hsa‐miR‐126‐3p, miR‐146b‐5p, miR‐155‐5p, miR‐16, miR‐17, miR‐326, and miR‐181c was evaluated in the PB‐MNCs. Expression analysis of the miRNAs was performed using qRT‐PCR and fold change was calculated by 2−ΔΔCt method. The alterations in the target genes of deregulated miRNAs were assessed by qRT‐PCR. The targets studied included various transcription factors, cytokines, and downstream proteins. Results: The absolute CD3+ lymphocytes were significantly elevated in the PB of aAA patients when compared with healthy controls (p < 0.0035), however, the CD4:CD8 ratio was unperturbed. Th17: Treg‐cell ratio was altered in aAA patients (9.1 vs. 3.7%, p value <0.05), which correlated positively with disease severity and the PNH positive aAA. Across all severities of aAA, altered expression of the 07 miRNAs was noted in comparison to controls; upregulation of miR‐155 (FC—2.174, p‐value‐0.0001), miR‐146 (FC—2.006, p‐value‐0.0001), and miR‐17 (FC—3.1, p‐value‐0.0001), and downregulation of miR‐126 (FC—0.329, p‐value‐0.0001), miR‐181c (FC—0.317, p‐value‐0.0001), miR‐16 (FC—0.348, p‐value‐0.0001), and miR‐326 (FC—0.334, p‐value‐0.0001). Target study for these miRNAs revealed an increased expression of transcription factors responsible for Th1 and Th17 differentiation (T‐bet, RORϒt, IL‐17, IL‐6, and IFN‐ϒ), T‐cell activation (NFκB, MYC, and PIK3R2), downregulation of FOX‐P3, and other regulatory downstream molecules like SHIP‐1, ETS‐1, IRAK‐1, TRAF‐6, and PTEN. Conclusion: The study for the first time highlights the plausible role of different miRNAs in deregulating the Th17/Treg‐cell imbalance in aAA, and comprehensively suggest the role of altered NF‐kB and mTOR pathways in aAA. The axis may be actively explored for development of newer therapeutic targets in aAA. [ABSTRACT FROM AUTHOR]

The current in-vivo study was premeditated to uncover the protective role of ezetimibe (EZ) against advanced glycation endproducts (AGEs)-related pathologies in experimental diabetes. Our results showed that EZ markedly improved the altered biochemical markers of diabetes mellitus (DM) (FBG, HbA1c, insulin, microalbumin, and creatinine) and cardiovascular disease (in-vivo lipid/lipoprotein level and hepatic HMG-CoA reductase activity) along with diminished plasma carboxymethyl-lysine (CML) and renal fluorescent AGEs level. Gene expression study revealed that EZ significantly down-regulated the renal AGEs-receptor (RAGE), nuclear factor-κB (NFκB-2), transforming growth factor-β (TGF-β1), and matrix metalloproteinase-2 (MMP-2) mRNA expression, however, the neuropilin-1 (NRP-1) mRNA expression was up-regulated. In addition, EZ also maintained the redox status via decreasing the lipid peroxidation and protein-bound carbonyl content (CC) and increasing the activity of high-density lipoprotein (HDL)-associated-paraoxonase-1 (PON-1) and renal antioxidant enzymes as well as also protected renal histopathological features. We conclude that EZ exhibits antidiabetic and reno-protective properties in diabetic rats. [ABSTRACT FROM AUTHOR]

Introduction: Idiopathic acquired aplastic anemia (AA) is a bone marrow failure disorder where aberrant T-cell functions lead to depletion of hematopoietic stem and progenitor cells in the bone marrow (BM) microenvironment. T-cells undergo metabolic rewiring, which regulates their proliferation and differentiation. Therefore, studying metabolic variation in AA patients may aid us with a better understanding of the T-cell regulatory pathways governed by metabolites and their pathological engagement in the disease. Objective: To identify the differential metabolites in BM plasma of AA patients, AA follow-up (AAF) in comparison to normal controls (NC) and to identify potential disease biomarker(s). Methods: The study used 1D 1H NMR Carr–Purcell–Meiboom–Gill (CPMG) spectra to identify the metabolites present in the BM plasma samples of AA (n = 40), AAF (n = 16), and NC (n = 20). Metabolic differences between the groups and predictive biomarkers were identified by using multivariate analysis and receiver operating characteristic (ROC) module of Metaboanalyst V5.0 tool, respectively. Results: The AA and AAF samples were well discriminated from NC group as per Principal Component analysis (PCA). Further, we found significant alteration in the levels of 17 metabolites in AA involved in amino-acid (Leucine, serine, threonine, phenylalanine, lysine, histidine, valine, tyrosine, and proline), carbohydrate (Glucose, lactate and mannose), fatty acid (Acetate, glycerol myo-inositol and citrate), and purine metabolism (hypoxanthine) in comparison to NC. Additionally, biomarker analysis predicted Hypoxanthine and Acetate can be used as a potential biomarker. Conclusion: The study highlights the significant metabolic alterations in the BM plasma of AA patients which may have implication in the disease pathobiology. [ABSTRACT FROM AUTHOR]

Non-alcoholic steatohepatitis (NASH) is a clinically serious stage of non-alcoholic fatty liver disease (NAFLD). Histologically characterized by hepatocyte ballooning, immune cell infiltration, and fibrosis, NASH, at a molecular level, involves lipid-induced hepatocyte death and cytokine production. Currently, there are very few diagnostic biomarkers available to screen for NASH, and no pharmacological intervention is available for its treatment. In this study, we show that hepatocyte damage induced by lipotoxicity results in the release of extracellular RNAs (eRNAs), which serve as damage-associated molecular patterns (DAMPs) that stimulate the expression of pro-apoptotic and pro-inflammatory cytokines, aggravate inflammation, and lead to cell death in HepG2 cells. Furthermore, the inhibition of eRNA activity by RNase 1 significantly increases cellular viability and reduces NF-kB-mediated cytokine production. Similarly, RNase 1 administration significantly improves hepatic steatosis, inflammatory and injury markers in a murine NASH model. Therefore, this study, for the first time, underscores the therapeutic potential of inhibiting eRNA action as a novel strategy for NASH treatment. [ABSTRACT FROM AUTHOR]

Autophagy and telomere maintenance are two cellular survival processes that show a strong correlation during human ageing and cancer growth, however, their causal relationship remains unclear. In this study, using an unbiased transcriptomics approach, we uncover a novel role of autophagy genes in regulating telomere extension and maintenance pathways. Concomitantly, the pharmacological inhibition of ULK1 (Unc-51 like autophagy activating kinase 1) attenuated human telomerase reverse transcriptase (hTERT) gene expression and telomerase activity in HepG2 cells. Furthermore, the suppression of telomerase activity upon ULK1 inhibition was associated with telomere shortening and onset of cellular senescence in HepG2 cells. These results, thus, demonstrate a direct role of autophagy in maintaining cellular longevity via regulation of telomerase activity, which may have implications in the pathophysiology of ageing and cancers. • ULK1 inhibition leads to reduced telomerase activity. • ULK1 inhibition promotes onset of cellular senescence. • Autophagy inhibition results in reduced signaling via IL-6-STAT3 pathway regulating hTERT transcription. [ABSTRACT FROM AUTHOR]

Advanced glycation end products (AGEs) trigger intracellular reactive oxygen species (ROS) generation, activation of receptor for AGEs (RAGE) expression/functionality and RAGE-associated signalling pathways which influence the diabetic-cum-atherosclerotic complications, whereas, the atherosclerosis progression is greatly influenced by hepatic β-Hydroxy-β-methyl-glutaryl-Co-A reductase (HMG-R) activity. The present report was premeditated to uncover the regulatory role of HMG-R inhibitors and ezetimibe (EZ) in attenuating the LDL-AGEs-induced pathogenicity via targeting cellular-ROS and RAGE-associated signalling in HEK-293 cells. The MTT assay was used to assess either the cytotoxic or cytoprotective impact of each HMG-R inhibitors, EZ, and LDL-AGEs, whereas, quantification of ROS was performed by DCFDA method. The qRT-PCR was used to detect the mRNA level of RAGE, neuropilin-1 (NRP-1) and other RAGE-associated genes like MMP-2, NF-κB, and TGFβ-1. The HMG-R inhibitors do not exert any cytotoxicity in HEK-293 cells, whereas, and LDL-AGEs negatively affected the cell viability of HEK-293 cells. However, viability of LDL-AGEs-treated HEK-293was markedly retained after simultaneous treatment with our test inhibitors. Further, DCFDA staining showed that LDL-AGEs-induced ROS was also suppressed upon treatment with our test inhibitors in HEK-293 cells. qRT-PCR analysis reflected that these inhibitors suppress the RAGE, NF-κB, TGFβ-1, and MMP-2 expression, whereas, the NRP-1 was up-regulated by these compounds in LDL-AGEs-exposed HEK-293 cells. The above pharmacological effects signify that HMG-R inhibitors and EZ (alone or in combination) may implied in the treatment of AGEs-induced oxidative stress and tissue damage in diabetic complications via targeting intracellular-ROS, NRP-1 functionality and RAGE-associated genes i.e. NF-κB, TGFβ-1, and MMP-2. Unlabelled Image [ABSTRACT FROM AUTHOR]