Cyclic Peptidomimetics as Inhibitor for miR-155 Biogenesis.
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ABSTRACT:
SUBMITTER: Yan H
PROVIDER: S-EPMC8513084 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:The regulation of mitochondrial biogenesis is under the control of nuclear genes including the master Mitochondrial Transcription Factor A (TFAM). Recent evidence suggests that the expression of TFAM is regulated by microRNAs (miRNAs) in various cellular contexts. Here, we show that hsa-miR-155-5p, a prominent miRNA encoded in chromosome 21, controls the expression of TFAM at the post-transcriptional level. In human fibroblasts derived from a diploid donor, downregulation of TFAM by hsa-miR-155-5p decreased mitochondrial DNA (mtDNA) content. In contrast, downregulation of TFAM by hsa-miR-155-5p did not decrease mtDNA content in fibroblasts derived from a donor with Down syndrome (DS, trisomy 21). In line, downregulation of mitochondrial TFAM levels through hsa-miR-155-5p decreased mitochondrial mass in diploid fibroblasts but not in trisomic cells. Due to the prevalence of mitochondrial dysfunction and cardiac abnormalities in subjects with DS, we examined the presence of potential associations between hsa-miR-155-5p and TFAM expression in heart samples from donors with and without DS. There were significant negative associations between hsa-miR-155-5p and TFAM expression in heart samples from donors with and without DS. These results suggest that regulation of TFAM by hsa-miR-155-5p impacts mitochondrial biogenesis in the diploid setting but not in the DS setting.
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Project description:BackgroundHuazhuo Tiaozhi granule (HTG) is a herbal medicine formula widely used in clinical practice for hypolipidaemic effects. However, the molecular mechanisms underlying dyslipidaemia treatment have not been well elucidated.ResultsA significant reduction in the levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) was observed in the serum of patients with dyslipidaemia after HTG treatment, without disruption in the levels of aspartate transaminase (AST), alanine transaminase (ALT), urea nitrogen (BUN), and creatinine (Cr). The dyslipidaemia rat model was induced by a high-fat diet and treated with Xuezhikang (0.14 g/kg/d) or HTG (9.33 g crude herb/kg/day) by gavage for 8 weeks. Body weight and liver index were markedly decreased in dyslipidaemic rats after treatment with Xuezhikang or HTG. HTG administration markedly ameliorated hyperlipidaemia by decreasing the levels of TC and LDL-C in serum and hepatic lipid accumulation. In vitro, lipid accumulation in LO2 and HepG2 cells was alleviated by serum treatment with HTG. High lactylation was observed in 198 proteins, including lactylation of histone H2B (K6), H4 (K80). Deep sequencing of microRNAs showed that miR-155-5p was significantly downregulated.ConclusionsThis study demonstrates that HTG is an effective and safe formula for treating dyslipidaemia, which promotes lactylation in hepatocytes, and the retardation of miR-155-5p biogenesis.
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Project description:Introduction: Acute graft vs. host disease (aGvHD) is a frequent complication following allogeneic haematopoeitic transplantation (HSCT). Despite recent advances, there are no universally accepted biomarkers to determine development of aGvHD. MicroRNAs miR-146a and miR-155 have been previously associated with aGvHD and show promise as clinically translatable biomarkers. In this study, we performed comprehensive expression profiling of miR-146a, miR-155, and miR-155* expression in aGvHD target tissue and biofluids and relate expression to post-HSCT outcomes. Materials and Methods: MicroRNA expression was assessed by qRT-PCR in gastrointestinal (n = 31) and skin (n = 31) biopsies as well as serum (exploratory cohort n = 34, verification cohort n = 81, diagnostic cohort n = 65) and urine (exploratory cohort n = 30, verification cohort n = 56, diagnostic cohort n = 20) biofluids, including extracellular vesicle (EV) cohorts (serum EV n = 15, urine EV n = 30). Expression was related to aGvHD incidence, severity and overall survival. Results: In GI samples, expression of miR-155 (p = 0.03) and miR-146a (p = 0.03) was higher at aGvHD onset compared to patients with no GvHD. In skin biopsies, expression of miR-155 (p = 0.004) was upregulated in aGvHD patients compared to normal control skin. Expression of miR-146a was higher in aGvHD compared to no aGvHD biopsies (p = 0.002). In serum, miR-155 (p = 0.03) and miR-146a (p = 0.02) expression was higher at day 14 (D14), while in urine expression was elevated at D7 post-HSCT in patients who developed aGvHD compared to those disease-free. This was verified in an independent serum (miR-155 p = 0.005, miR-146a p = 0.003) and urine (miR-155 p = 0.02, miR-146a p = 0.04) cohort, where both microRNAs were also associated with aGvHD by ROC analysis. In serum and urine samples taken at the time of aGvHD symptoms, expression of miR-155 and miR-146a was also elevated (serum miR-155 p = 0.03, miR-146a p < 0.001; urine miR-155 p = 0.02, miR-146a p = 0.02). In contrast, miR-146a and miR-155 were downregulated at D14 in serum EVs and at D7 in urine EVs in patients who developed aGvHD compared to those that remained disease-free, in both an exploratory (serum miR-155 p = 0.02, miR-146a p = 0.06; urine miR-155 p = 0.02, miR-146a p = 0.07) and an independent cohort (serum miR-155 p = 0.01, miR-146a p = 0.02). Conclusions: These results further support a role for miR-155 and miR-146a as non-invasive, clinically relevant biomarkers for aGvHD. However, the link between their involvement in generalized inflammation and in specific pathophysiology requires further investigation at a systemic level.
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