Let-7 suppresses liver fibrosis by inhibiting hepatocyte apoptosis and TGF-β production

Research progress of non-coding RNA regulating the role of PANoptosis in diabetes mellitus and its complications

Diabetes is a chronic metabolic disease that is endemic worldwide and is characterized by persistent hyperglycemia accompanied by multiple severe complications, including cardiovascular disease, kidney dysfunction, neuropathy, and retinopathy. The pathogenesis of diabetes mellitus and its complications is multifactorial, involving various molecular and cellular pathways. In recent years, research has indicated that mechanisms of cell death play a significant role in the advancement of diabetes and its complications. PANoptosis is a complex phenomenon caused by three cell death pathways: programmed apoptosis, necroptosis and pyroptosis. The contribution of PANoptosis to diabetes and its complications remains incompletely understood. Non-coding RNA, an important molecule in gene expression regulation, has shown significant regulatory functions in a variety of diseases. This paper reviews the underlying mechanisms of diverse types of non-coding RNAs (including lncRNA, miRNA and circRNA) in regulating PANoptosis and their specific contributions in diabetes, aiming to explore how non-coding RNAs influence PANoptosis and their effects in diabetes.

GAMG alleviates liver fibrosis through inducing ferroptosis in inflammatory macrophages via the IRF1/SLC7A11 signaling pathway

The activation of inflammatory macrophages plays a pivotal role in the development of liver fibrosis (LF). Ferroptosis contributes to the clearance of inflammatory macrophages and the release of profibrotic factors. Glycyrrhetic Acid 3-O-Mono-β-d-glucuronide (GAMG) is a natural compound, the potential role of which on LF remains uncertain. In this study, GAMG treatment significantly reduced hepatocyte steatosis, fibroplasia, inflammatory cell infiltration, and collagen fiber deposition in LF mice. In addition, GAMG remarkably decreased the content of collagen protein and improved liver function indicators. Single-cell RNA sequencing revealed that GAMG significantly affected the changes of macrophage subsets in LF, and Funrich analysis identified IRF1 as a key transcription factor regulating the macrophage genome. IRF1 was significantly increased while ferroptosis related SLC7A11 was significantly down-regulated in GAMG treated inflammatory macrophages. Mass spectrometry metabolomics analysis showed that GAMG significantly affected metabolites associated with LF. In vivo and in vitro experiments further verified that GAMG induced ferroptosis of inflammatory macrophages through the IRF1/SLC7A11 axis, and ultimately alleviated LF. Therefore, GAMG induces ferroptosis of inflammatory macrophages by activating the IRF1/SLC7A11 axis, which provides a new strategy for the treatment of LF.

Shugan Jianpi Formula attenuate liver fibrosis via regulation of miR-193a-3p/TGF-β2 in hepatic stellate cells: An in vivo and in vitro study

ETHNOPHARMACOLOGICAL RELEVANCE

The Chinese herbal medicine Shugan Jianpi Formula (SGJPF) has traditionally been used to treat various chronic liver disorders. Previous studies have indicated that SGJPF inhibits hepatic stellate cells (HSCs) activation in rats with liver fibrosis (LF) and that miR-193a-3p may be a crucial molecule in LF. However, the mechanisms by which SGJPF regulates HSCs activation through miR-193a-3p remain unclear.

AIM OF THE STUDY

This study aimed to determine whether the effect of SGJPF on LF is related to its regulation of miR-193a-3p and TGF-β2, both in a carbon tetrachloride (CCl4)-induced LF mouse model and in TGF-β1-induced JS-1 cells.

MATERIALS AND METHODS

A CCl4-induced LF mouse model was established to evaluate the anti-fibrotic efficacy of SGJPF by examining liver histopathological changes, collagen deposition, and the expression of α-smooth muscle actin (α-SMA) and collagen-I. To investigate the role of miR-193a-3p in HSCs activation, miR-193a-3p mimics and inhibitors were transfected into TGF-β1-induced JS-1 cells. The potential targets of miR-193a-3p were identified using miRDB, TargetScan 8.0, RNA-seq, and dual-luciferase reporter assays. Finally, the effects of SGJPF on HSCs activation and the miR-193a-3p/TGF-β2 axis were assessed in TGF-β1-treated JS-1 cells using CCK-8, EDU, scratch, RT-qPCR, and Western blotting assays.

RESULTS

SGJPF significantly reduced liver damage and fibrosis, inhibited HSCs activation, decreased TGF-β2 levels, and increased miR-193a-3p expression in CCl4-induced LF tissue. Additionally, miR-193a-3p was upregulated in HSCs transfected with miR-193a-3p mimics and downregulated in those with miR-193a-3p inhibitors. High levels of miR-193a-3p, combined with miRNA mimics, inhibited HSCs activation, proliferation, and migration. TGF-β2, a target negatively regulated by miR-193a-3p, partially reversed the effects of miR-193a-3p on TGF-β1-induced HSCs activation. SGJPF also reduced HSCs activation, proliferation, and migration in TGF-β1-treated JS-1 cells. Moreover, treatment with SGJPF-containing serum and miR-193a-3p inhibition restored HSCs activation, proliferation, and migration in TGF-β1-induced JS-1 cells.

CONCLUSIONS

This study demonstrates that SGJPF ameliorates CCl4-induced liver fibrosis, which is associated with the regulation of miR-193a-3p and TGF-β2 in HSCs. These findings provide a new pharmacological basis for SGJPF and suggest a novel strategy for treating LF through TCM by regulating miRNAs.

Role of miRNAs in Regulating Ascending Aortic Dilation in Bicuspid Aortic Valve Patients Operated for Aortic Stenosis

Deregulation of micro-RNAs (miRNAs) may contribute to mechanisms of injury in the bicuspid aortic valve (BAV). Our objective was to investigate the expression of miRNAs in aortic tissue from patients who underwent aortic valve replacement for aortic stenosis and its relationship with aortic dilatation. The study included 78 patients, 40 with bicuspid aortic valve (BAV) and 38 with tricuspid aortic valve (TAV). The expression of miRNA-17-5p, hsa-let-7e, and miRNA-196a-5p in human aortic tissue was evaluated by a reverse transcriptase polymerase chain reaction (RT-qPCR). Comparative analysis between patients with BAV and controls with TAV explored the association between the miRNAs and aortic dilatation (AD), calcification, valve dysfunction, and stenosis. The results showed that the expression levels of miRNA-Let-7e-5p and miRNA-196-5p were mostly increased in patients with BAV and aortic dilatation (p = 0.01 and p = 0.01), respectively. In contrast, the levels of miRNA-17a-5p (p < 0.20) were lower but without a statistically significant difference. The downregulation of miRNA-17a-5p and the upregulation of miR-Let-7e-5p and miR-196-5p were related to an increased risk of AD risk. Subjects with BAVs with or without double aortic lesions had higher expression levels of Let-7e-5p and miRNA-17a-5p vs. TAV. In all patients, we found an inverse correlation of MiRNA-196-5p with High-Density Lipoprotein-Cholesterol (HDL-C) and indexed valvular area. In subjects with a higher expression of miRNA196, lower levels of HDL-C correlation (r2) [r2 0.27 (p = 0.02)] and a lower indexed valvular area [r2 0.28 (p = 0.05)] were observed. In the specific analysis for each patient group, it was found that in control subjects with tricuspid aortic valve (TAV), miRNA-196-5p had a positive correlation with valvular calcification (r2 = 0.60, p = 0.02). Deregulation of miRNAs in the aortic tissue of a BAV may influence valvular stenosis, dysfunction, and concomitant aortic dilation. This information could help to define potential therapeutic target strategies to improve the prognosis and treatment of BAV.

The role of ferroptosis-related non-coding RNA in liver fibrosis

Liver fibrosis represents a reversible pathophysiological process, caused by chronic inflammation stemming from hepatocyte damage. It delineates the initial stage in the progression of chronic liver disease. This pathological progression is characterized by the excessive accumulation of the extracellular matrix (ECM), which leads to significant structural disruption and ultimately impairs liver function. To date, no specific antifibrotic drugs have been developed, and advanced liver fibrosis remains largely incurable. Liver transplantation remains the sole efficacious intervention for advanced liver fibrosis; nevertheless, it is constrained by exorbitant costs and the risk of postoperative immune rejection, underscoring the imperative for novel therapeutic strategies. Ferroptosis, an emergent form of regulated cell death, has been identified as a pivotal regulatory mechanism in the development of liver fibrosis and is intricately linked with the progression of liver diseases. Recent investigations have elucidated that a diverse array of non-coding RNAs (ncRNAs), including microRNAs, long non-coding RNAs, and circular RNAs, are involved in the ferroptosis pathway, thereby modulating the progression of various diseases, including liver fibrosis. In recent years, the roles of ferroptosis and ferroptosis-related ncRNAs in liver fibrosis have attracted escalating scholarly attention. This paper elucidates the pathophysiology of liver fibrosis, explores the mechanisms underlying ferroptosis, and delineates the involvement of ncRNA-mediated ferroptosis pathways in the pathology of liver fibrosis. It aims to propose novel strategies for the prevention and therapeutic intervention of liver fibrosis.

TET3-overexpressing macrophages promote endometriosis

Endometriosis is a debilitating, chronic inflammatory disease affecting approximately 10% of reproductive-age women worldwide with no cure. While macrophages have been intrinsically linked to the pathophysiology of endometriosis, targeting them therapeutically has been extremely challenging due to their high heterogeneity and because these disease-associated macrophages (DAMs) can be either pathogenic or protective. Here, we report identification of pathogenic macrophages characterized by TET3 overexpression in human endometriosis lesions. We show that factors from the disease microenvironment upregulated TET3 expression, transforming macrophages into pathogenic DAMs. TET3 overexpression stimulated proinflammatory cytokine production via a feedback mechanism involving inhibition of let-7 miRNA expression. Remarkably, these cells relied on TET3 overexpression for survival and hence were vulnerable to TET3 knockdown. We demonstrated that Bobcat339, a synthetic cytosine derivative, triggered TET3 degradation in both human and mouse macrophages. This degradation was dependent on a von Hippel-Lindau (VHL) E3 ubiquitin ligase whose expression was also upregulated in TET3-overexpressing macrophages. Furthermore, depleting TET3-overexpressing macrophages either through myeloid-specific Tet3 ablation or using Bobcat339 strongly inhibited endometriosis progression in mice. Our results defined TET3-overexpressing macrophages as key pathogenic contributors to and attractive therapeutic targets for endometriosis. Our findings may also be applicable to other chronic inflammatory diseases where DAMs have important roles.

Exosomal let-7b-5p deriving from parietal epithelial cells attenuate renal fibrosis through suppression of TGFβR1 and ARID3a in obstructive kidney disease

As renal progenitor cells, parietal epithelial cells (PECs) have demonstrated multilineage differentiation potential in response to kidney injury. However, the function of exosomes derived from PECs has not been extensively explored. Immunofluorescent staining of Claudin-1 was used to identify primary PECs isolated from mouse glomeruli. Transmission electron microscopy, nanoparticle tracking analysis, and western blotting were used to characterize the properties of PECs-derived exosomes (PEC-Exo). The therapeutic role of PEC-Exo in tubulointerstitial fibrosis was investigated in the unilateral ureteral obstruction (UUO) mouse model and TGF-β1-stimulated HK-2 cells. High-throughput miRNA sequencing was employed to profile PEC-Exo miRNAs. One of the most enriched miRNAs in PEC-Exo was knocked down by transfecting miRNA inhibitor, and then we investigated whether this candidate miRNA was involved in PEC-Exo-mediated tubular repair. The primary PECs expressed Claudin-1, PEC-Exo was homing to obstructed kidney, and TGF-β1 induced HK-2 cells. PEC-Exo significantly alleviated renal inflammation and ameliorated tubular fibrosis both in vivo and in vitro. Mechanistically, let-7b-5p, highly enriched in PEC-Exo, downregulated the protein levels of transforming growth factor beta receptor 1(TGFβR1) and AT-Rich Interaction Domain 3A(ARID3a) in tubular epithelial cells (TECs), leading to the inhibition of p21 and p27 to restoring cell cycle. Furthermore, administration of let-7b-5p agomir mitigated renal fibrosis in vivo. Our findings demonstrated that PEC-derived exosomes significantly repressed the expression of TGFβR1 and ARID3a by delivering let-7b-5p, thereby alleviating renal fibrosis. This study provides novel insights into the role of PEC-Exo in the repair of kidney injury and new ideas for renal fibrosis intervention.

Skeletal muscle TET3 promotes insulin resistance through destabilisation of PGC-1α

AIM/HYPOTHESIS

The peroxisome proliferator-activated receptor-γ coactivator α (PGC-1α) plays a critical role in the maintenance of glucose, lipid and energy homeostasis by orchestrating metabolic programs in multiple tissues in response to environmental cues. In skeletal muscles, PGC-1α dysregulation has been associated with insulin resistance and type 2 diabetes but the underlying mechanisms have remained elusive. This research aims to understand the role of TET3, a member of the ten-eleven translocation (TET) family dioxygenases, in PGC-1α dysregulation in skeletal muscles in obesity and diabetes.

METHODS

TET expression levels in skeletal muscles were analysed in humans with or without type 2 diabetes, as well as in mouse models of high-fat diet (HFD)-induced or genetically induced (ob/ob) obesity/diabetes. Muscle-specific Tet3 knockout (mKD) mice were generated to study TET3's role in muscle insulin sensitivity. Genome-wide expression profiling (RNA-seq) of muscle tissues from wild-type (WT) and mKD mice was performed to mine deeper insights into TET3-mediated regulation of muscle insulin sensitivity. The correlation between PGC-1α and TET3 expression levels was investigated using muscle tissues and in vitro-derived myotubes. PGC-1α phosphorylation and degradation were analysed using in vitro assays.

RESULTS

TET3 expression was elevated in skeletal muscles of humans with type 2 diabetes and in HFD-fed and ob/ob mice compared with healthy controls. mKD mice exhibited enhanced glucose tolerance, insulin sensitivity and resilience to HFD-induced insulin resistance. Pathway analysis of RNA-seq identified 'Mitochondrial Function' and 'PPARα Pathway' to be among the top biological processes regulated by TET3. We observed higher PGC-1α levels (~25%) in muscles of mKD mice vs WT mice, and lower PGC-1α protein levels (~25-60%) in HFD-fed or ob/ob mice compared with their control counterparts. In human and murine myotubes, increased PGC-1α levels following TET3 knockdown contributed to improved mitochondrial respiration and insulin sensitivity. TET3 formed a complex with PGC-1α and interfered with its phosphorylation, leading to its destabilisation.

CONCLUSIONS/INTERPRETATION

Our results demonstrate an essential role for TET3 in the regulation of skeletal muscle insulin sensitivity and suggest that TET3 may be used as a potential therapeutic target for the metabolic syndrome.

DATA AVAILABILITY

Sequences are available from the Gene Expression Omnibus ( https://www.ncbi.nlm.nih.gov/geo/ ) with accession number of GSE224042.