Unlabelled: Hepatic stellate cell (HSC) activation is a pivotal event in initiation and progression of hepatic fibrosis and a major contributor to collagen deposition driven by transforming growth factor beta (TGF-β). MicroRNAs (miRs), small noncoding RNAs modulating messenger RNA (mRNA) and protein expression, have emerged as key regulatory molecules in chronic liver disease. We investigated differentially expressed miRs in quiescent and activated HSCs to identify novel regulators of profibrotic TGF-β signaling. miR microarray analysis was performed on quiescent and activated rat HSCs. Members of the miR-17-92 cluster (19a, 19b, 92a) were significantly down-regulated in activated HSCs. Because miR 19b showed the highest fold-change of the cluster members, activated HSCs were transfected with miR 19b mimic or negative control and TGF-β signaling and HSC activation assessed. miR 19b expression was determined in fibrotic rat and human liver specimens. miR 19b mimic negatively regulated TGF-β signaling components demonstrated by decreased TGF-β receptor II (TGF-βRII) and SMAD3 expression. Computational prediction of miR 19b binding to the 3' untranslated region of TGF-βRII was validated by luciferase reporter assay. Inhibition of TGF-β signaling by miR 19b was confirmed by decreased expression of type I collagen and by blocking TGF-β-induced expression of α1(I) and α2(I) procollagen mRNAs. miR 19b blunted the activated HSC phenotype by morphological assessment and decreased smooth muscle α-actin expression. Additionally, miR 19b expression was markedly diminished in fibrotic rat liver compared with normal liver; similarly, miR 19b expression was markedly down-regulated in fibrotic compared with normal human livers.
Conclusion: miR 19b is a novel regulator of TGF-β signaling in HSCs, suggesting a potential therapeutic approach for hepatic fibrosis.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3342471 | PMC |
http://dx.doi.org/10.1002/hep.25613 | DOI Listing |
J ECT
January 2025
Division of Biology and Genetics, Department of Molecular and Translational Medicine, University of Brescia, Brescia.
Objectives: Electroconvulsive therapy (ECT) is one of the most effective treatments for treatment-resistant depression (TRD), even though the molecular mechanisms underlying its efficacy remain largely unclear. This study aimed, for the first time, to analyze plasma levels of miRNAs, key regulators of gene expression, in TRD patients undergoing ECT to investigate potential changes during treatment and their associations with symptom improvement.
Methods: The study involved 27 TRD patients who underwent ECT.
Viruses
December 2024
1st Internal Medicine Department, AHEPA University Hospital, School of Medicine, Aristotle University of Thessaloniki, 55436 Thessaloniki, Greece.
People with HIV (PWH) have an elevated risk of cardiovascular disease compared to those without HIV. This study aimed to investigate the relative serum expression of microRNAs (miRNAs) associated with arterial stiffness, a significant marker of cardiovascular disease. A total of 36 male PWH and 36 people without HIV, matched for age, body mass index, pack years, and dyslipidemia, were included in the study.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Dermatology, Faculty of Medicine, Fayoum University, Fayoum, Egypt.
Vitiligo is a common long-term depigmenting skin disorder that is characterized by patches of skin losing their pigment. To evaluate serum/tissue levels of miR-16, 146a, 19b and 720 in vitiligo patients and healthy controls, also analyzing the correlations between all biomarkers to indicate whether those can be used to early diagnose vitiligo patients. Forty-subjects were included, divided into two equal groups, 20 healthy matched individuals and 20 vitiligo patients.
View Article and Find Full Text PDFBMC Bioinformatics
December 2024
School of Computing, University of Nebraska-Lincoln, 1400 R St, Lincoln, NE, 68588-0115, USA.
Background: Interactions between microRNAs and RNA-binding proteins are crucial for microRNA-mediated gene regulation and sorting. Despite their significance, the molecular mechanisms governing these interactions remain underexplored, apart from sequence motifs identified on microRNAs. To date, only a limited number of microRNA-binding proteins have been confirmed, typically through labor-intensive experimental procedures.
View Article and Find Full Text PDFZhen Ci Yan Jiu
December 2024
College of Acupuncture-moxibustion and Tuina, Anhui University of Chinese Medicine, Hefei 230038, China.
Objectives: To explore whether electroacupuncture(EA) can increase the expression of suppressor of cytokine signaling (SOCS)3 by affecting the expression of miR-19b-3p, inhibiting the continuous activation of janus kinase (JAK)1 /signal transducer and activator of transcription (STAT)3 signaling pathway, and improve pulmonary inflammation in chronic obstructive pulmonary disease (COPD) mice.
Methods: Forty mice were randomly divided into normal, COPD model, COPD+EA, and COPD+miR-19b-3p agomir (agomir)+EA groups. The COPD model was simulated by cigarette smoke exposure for 1 h, twice a day for 3 months.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!