Downregulation of miR-497-5p prevents liver ischemia-reperfusion injury in association with MED1/TIMP-2 axis and the NF-κB pathway

The dysregulation of plasma miR-497/FGF23 axis, and its association with clinical characteristics and major adverse cardiovascular event in female premature acute coronary syndrome patients

AIM

MicroRNA-497 (miR-497) directly targets fibroblast growth factor 23 (FGF23) to participate in the pathology of acute coronary syndrome (ACS) by regulating atherosclerosis, inflammatory response, lipid metabolism, etc. This study intended to investigate the dysregulation of the miR-497/FGF23 axis, and its association with the major adverse cardiovascular event (MACE) in female premature ACS.

METHODS

MiR-497 and FGF23 from plasma samples were detected by RT-qPCR and ELISA in 979 newly diagnosed female premature ACS patients and 100 healthy controls (HCs). MACE was recorded during follow-up (median: 27.0, range: 1.0-54.0 months) in female premature ACS patients.

RESULTS

MiR-497/FGF23 axis was reduced in female premature ACS patients versus HCs [median (interquartile range): 0.7 (0.1-1.2) versus 1.9 (1.1-3.4)] (P < 0.001). Meanwhile, miR-497 negatively correlated with FGF23 in femal e premature ACS patients (P < 0.001), but not in HCs (P = 0.157). In female premature ACS patients, the miR-497/FGF23 axis was negatively associated with serum creatinine (P < 0.001), serum uric acid (P = 0.003), high-sensitivity C-reactive protein (P < 0.001), total cholesterol (P = 0.031), and low-density lipoprotein cholesterol (P = 0.003). The 1-year, 2-year, 3-year, and 4-year accumulating MACE rate was 2.9%, 8.6%, 16.7%, and 26.0%, respectively. Interestingly, a high level of miR-497/FGF23 axis predicted decreased accumulating MACE risk (P < 0.001). After adjustment by multivariate Cox's regression analysis, the high miR-497/FGF23 axis (hazard ratio (HR) = 0.005, P = 0.001) independently correlated with reduced accumulating MACE risk.

CONCLUSION

The plasma miR-497/FGF23 axis represents favorable kidney function, decreased inflammation, and reduced lipid level; meanwhile, this axis possesses prognostic value in predicting decreased accumulating MACE risk in female premature ACS patients.

Matrix metalloproteinases induce extracellular matrix degradation through various pathways to alleviate hepatic fibrosis

Liver fibrosis is the common consequence of various chronic liver injuries and is mainly characterized by the imbalance between the production and degradation of extracellular matrix, which leads to the accumulation of interstitial collagen and other matrix components. Matrix metalloproteinases (MMPs) and their specific inhibitors, that is, tissue inhibitors of metalloproteinases (TIMPs), play a crucial role in collagen synthesis and lysis. Previous in vivo and in vitro studies of our laboratory found repressing extracellular matrix (ECM) accumulation by restoring the balance between MMPs and TIMPs can alleviate liver fibrosis. We conducted a review of articles published in PubMed and Science Direct in the last decade until February 1, 2023, which were searched for using these words "MMPs/TIMPs" and "Hepatic Fibrosis." Through a literature review, this article reviews the experimental studies of liver fibrosis based on MMPs/TIMPs, summarizes the components that may exert an anti-liver fibrosis effect by affecting the expression or activity of MMPs/TIMPs, and attempts to clarify the mechanism of MMPs/TIMPs in regulating collagen homeostasis, so as to provide support for the development of anti-liver fibrosis drugs. We found the MMP-TIMP-ECM interaction can result in better understanding of the pathogenesis and progression of hepatic fibrosis from a different angle, and targeting this interaction may be a promising therapeutic strategy for hepatic fibrosis. Additionally, we summarized and analyzed the drugs that have been found to reduce liver fibrosis by changing the ratio of MMPs/TIMPs, including medicine natural products.

MicroRNAs: Novel Targets in Hepatic Ischemia–Reperfusion Injury

Hepatic ischemia–reperfusion injury (IRI) is one of the main factors for early allograft dysfunction (EAD), which may lead to graft rejection, graft loss, or shortened graft life in liver transplantation. Hepatic IRI appears to be inevitable during the majority of liver procurement and transportation of donor organs, resulting in a cascade of biological changes. The activation of signaling pathways during IRI results in the up- and downregulation of genes and microRNAs (miRNAs). miRNAs are ~21 nucleotides in length and well-characterized for their role in gene regulations; they have recently been used for therapeutic approaches in addition to their role as biomarkers for many diseases. miRNAs that are associated with hepatic IRI in in vitro and in vivo animal models are comprehensively summarized in this review. In those studies, the manipulation of miRNAs has been shown for the inhibition of aggravated immune response, reduction of apoptosis, stimulation of tissue repair, and enhancement of cell recovery to attenuate liver damage. Therefore, the utilization of liver-specific miRNA holds great potential as a therapeutic agent to improve early allograft dysfunction, hepatic injury, and patient outcome.