METTL3-mediated N⁶-methyladenosine modification governs pericyte dysfunction during diabetes-induced retinal vascular complication

Abstract

Rationale: Microvascular complication is a major cause of morbidity and mortality among the patients with diabetes. Pericyte dysfunction is the predominant pathological manifestation of microvascular complication. N 6 -methyladenosine (m 6 A) serves as the most prevalent modification in eukaryotic mRNAs. However, the role of m 6 A RNA modification in pericyte dysfunction is still unclear. Methods: Quantitative polymerase chain reactions and western blots were conducted to detect the change of m 6 A RNA modification in pericytes and mouse retinas following diabetic stress. MTT assay, transwell migration assay, caspase 3/7 activity assay, calcein-AM/propidium iodide (PI) staining, and TUNEL staining were conducted to determine the role of METTL3 in pericyte biology in vitro . Retinal trypsin digestion, vascular permeability assay, and IB4-NG2 double immunofluorescent staining were conducted to determine the role of METTL3 in retinal pericyte dysfunction and vascular complication. RNA sequencing, RNA pull-down assays and immunoblots were conducted to clarify the mechanism of METTL3-mediated pericyte dysfunction and vascular complication. Results: The levels of m 6 A RNA methylation were significantly up-regulated in pericytes and mouse retinas following diabetic stress, which were caused by increased expression of METTL3. METTL3 regulated the viability, proliferation, and differentiation of pericytes in vitro . Specific depletion of METTL3 in pericytes suppressed diabetes-induced pericyte dysfunction and vascular complication in vivo . METTL3 overexpression impaired pericyte function by repressing PKC-η, FAT4, and PDGFRA expression, which was mediated by YTHDF2-dependent mRNA decay. Conclusion: METTL3-mediated m 6 A methylation epigenetically regulates diabetes-induced pericyte dysfunction. METTL3-YTHDF2-PKC-η/FAT4/PDGFRA signaling axis could be therapeutically targeted for treating microvascular complications.

Crosstalk among m6A RNA methylation, hypoxia and metabolic reprogramming in TME: from immunosuppressive microenvironment to clinical application

“…The m 6 A methyltransferase METTL3 stimulates EMT in lung cancer through the miR-143-3p/VASH1 axis for metastasis and invasion [ 165 ]. Additionally, increased vascular permeability may be mediated by m 6 A methylation in the METTL3-YTHDF2-PKC-η/FAT4/PDGFRA signaling axis [ 205 ], which supports the possibility of transendothelial migration of tumor cells. Given the effects of hypoxia and metabolism on TME, a feasible consideration is that these factors promote metastasis in concert with m 6 A modifications.…”

A bibliometric analysis of RNA methylation in diabetes mellitus and its complications from 2002 to 2022

“…The overexpression of METTL3 promoted cell proliferation by regulating miR-25-3p/PTEN/Akt signaling ( 53 ). However, in another study, the level of m 6 A RNA modification and METTL3 was increased in diabetic retinal vessels, and the increased METTL3 accelerated pericyte apoptosis and decreased pericyte viability ( 54 ). Based on the current research baseline and research background, RNA methylation may be a new hotspot and direction for research on other complications of DM and types of DM.…”

N6-methyladenosine modification: A potential regulatory mechanism in spinal cord injury

“…Previous studies have shown that pericytes are closely related to the formation of scars and the recovery of function after SCI (Dias et al, 2018;Hesp et al, 2018;Zhu et al, 2022). Some studies have confirmed that m6A modification in pericytes is involved in the occurrence and development of hypertension and diabetes (Wu Q. et al, 2019;Suo et al, 2022). For instance, Qingbin Wu et al discovered that in pericytes, mRNAs undergo m6A modification in coding regions under hypertensive conditions.…”

“…This suggests that changes in m6A modification in pericytes play a role in the pathogenesis of vascular diseases such as hypertension (Wu Q. et al, 2019). Moreover, a recent study found that diabetes-induced pericyte dysfunction is associated with changes in RNA m6A levels, which are regulated by m6A-related enzymes and proteins (Suo et al, 2022). Selective METTL3 silencing can reduce YTHDF2-induced degradation of PKC, FAT4, and PDGFRA mRNA, reducing the occurrence of diabetes-induced vascular complications and pericyte dysfunction (Suo et al, 2022).…”