MiRNA-324-5p inhibits inflammatory response of diabetic vessels by targeting CPT1A

Extracellular Vesicles in Metabolic and Vascular Insulin Resistance

BACKGROUND

Insulin resistance is a major etiological factor in obesity, type 2 diabetes, and cardiovascular disease (CVD). Endothelial dysfunction may precede impairments in insulin-stimulated glucose uptake, thereby making it a key feature in development of CVD. However, the mechanism by which vascular tissue becomes dysfunctional is not clear.

SUMMARY

Extracellular vesicles (EVs) have emerged as potential mediators of insulin resistance and vascular dysfunction. EVs are membrane-bound particles released by tissues following cellular stress or activation. They carry "cargo" (e.g., insulin signaling proteins, eNOS-nitric oxide, and miRNA) that are believed to promote inter-cellular and interorgan communications. Herein, we review the underlying physiology of EVs in relation to type 2 diabetes and CVD risk. Specifically, we discuss how EVs may modulate metabolic (e.g., skeletal muscle, liver, and adipose) insulin sensitivity, and propose that EVs may modulate vascular insulin action to influence both endothelial function and arterial stiffness. We lastly identify how EVs may play a unique role following exercise to promote metabolic and vascular insulin sensitivity changes.

KEY MESSAGE

Gaining insight toward insulin-mediated EV mechanism has potential to identify novel pathways regulating cardiometabolic health and provide foundation for examining EVs as unique biomarkers and targets to prevent and/or treat chronic diseases.

Exosomes as biomarkers and therapy in type 2 diabetes mellitus and associated complications

Type 2 diabetes mellitus (T2DM) is one of the most prevalent metabolic disorders worldwide. However, T2DM still remains underdiagnosed and undertreated resulting in poor quality of life and increased morbidity and mortality. Given this ongoing burden, researchers have attempted to locate new therapeutic targets as well as methodologies to identify the disease and its associated complications at an earlier stage. Several studies over the last few decades have identified exosomes, small extracellular vesicles that are released by cells, as pivotal contributors to the pathogenesis of T2DM and its complications. These discoveries suggest the possibility of novel detection and treatment methods. This review provides a comprehensive presentation of exosomes that hold potential as novel biomarkers and therapeutic targets. Additional focus is given to characterizing the role of exosomes in T2DM complications, including diabetic angiopathy, diabetic cardiomyopathy, diabetic nephropathy, diabetic peripheral neuropathy, diabetic retinopathy, and diabetic wound healing. This study reveals that the utilization of exosomes as diagnostic markers and therapies is a realistic possibility for both T2DM and its complications. However, the majority of the current research is limited to animal models, warranting further investigation of exosomes in clinical trials. This review represents the most extensive and up-to-date exploration of exosomes in relation to T2DM and its complications.

Downregulation of CPT1A exerts a protective effect in dextran sulfate sodium-induced ulcerative colitis partially by inhibiting PPARα signaling pathway

Ulcerative colitis (UC) is a chronic inflammatory bowel disease that may progress to colorectal cancer in severe cases. Carnitine palmitoyltransferase-1A (CPT1A) has been reported to be upregulated in colorectal cancer. This paper aims to explore the role of CPT1A in UC and its pathogenesis. An in vivo mice model of UC was constructed by administrating 3% dextran sulfate sodium (DSS). The expression level of CPT1A was examined by quantitative real-time polymerase chain reaction and Western blot. The intestinal damage, inflammatory response and oxidative stress were assessed by hematoxylin and eosin staining, colon length, and commercial kits. Thereafter, an in vitro cell model of UC was established by stimulating HT-29 cells with 2% DSS. The peroxisome proliferator-activated receptor α (PPARα) signaling agonist GW7647 was used for treatment. Cell viability and apoptosis was assayed by cell counting kit-8 assay and terminal dUTP nick-end labeling assay, respectively. The inflammatory cytokines and oxidative stress-related factors was evaluated using corresponding commercial detection kits. In DSS-induced mice model of UC, CPT1A expression was upregulated. Interference of CPT1A attenuated histological damage, the disease activity index and colon length in colitis. We also found downregulation of CPT1A inhibited inflammatory response and oxidative stress, and inhibited PPARα signaling pathway in UC mice. Additionally, in DSS-induced HT-29 cells, downregulation of CPT1A promoted cell viability, reduced cell apoptosis, inflammatory response, and oxidative stress, which was partly abolished by additional treatment with GW7647. In summary, downregulation of CPT1A exerts a protective effect in DSS-induced UC partially through suppressing PPARα signaling, suggesting that CPT1A might be a potential target for the treatment of UC.

Circulating miR-342-5p serves as a diagnostic biomarker in patients with carotid artery stenosis and predicts the occurrence of the cerebral ischemic event

BACKGROUND

Carotid artery stenosis (CAS) is an important risk factor for cerebral ischemia events (CIE). Previous studies have shown that microRNAs (miRNAs) are involved in the occurrence and development of CAS.

AIMS

The purpose of this study was to reveal the clinical diagnostic value of miR-342-5p for asymptomatic CAS (ACAS) and to evaluate its predictive value for the occurrence of CIE in patients.

METHODS

A total of 92 ACAS patients and 86 healthy controls were enrolled as subjects. The expression level of serum miR-342-5p was detected by qRT-PCR. The receiver operating characteristic (ROC) curve was used to detect the diagnostic value of miR-342-5p in ACAS. Kaplan-Meier survival and Cox regression analysis assessed the predictive value of miR-342-5p for the occurrence of CIE in ACAS patients.

RESULTS

The level of serum miR-342-5p in ACAS patients was significantly higher than that in healthy controls (P < 0.05). ROC curve showed the high diagnostic value of serum miR-342-5p, which could distinguish ACAS patients from healthy controls. Multivariate Cox regression analysis confirmed that miR-342-5p was an independent predictor (HR = 5.512, 95%CI = 1.370-22.176, P = 0.016). What is more, Kaplan-Meier analysis confirmed that patients with high miR-342-5p expression develop more CIE (log-rank, P = 0.020).

CONCLUSIONS

miR-342-5p was significantly overexpressed in ACAS. And the upregulation of serum miR-342-5p is a valuable diagnostic biomarker and can predict the occurrence of CIE.