Inhibition of hyperglycolysis in mesothelial cells prevents peritoneal fibrosis

Abstract

Progressive peritoneal fibrosis affects patients receiving peritoneal dialysis (PD) and has no reliable treatment. The mechanisms that initiate and sustain peritoneal fibrosis remain incompletely elucidated. To overcome these problems, we developed a strategy that prevents peritoneal fibrosis by suppressing PD-stimulated mesothelial-to-mesenchymal transition (MMT). We evaluated single-cell transcriptomes of mesothelial cells obtained from normal peritoneal biopsy and effluent from PD-treated patients. In cells undergoing MMT, we found cellular heterogeneity and intermediate transition states associated with up-regulation of enzymes involved in glycolysis. The expression of glycolytic enzymes was correlated with the development of MMT. Using gene expression profiling and metabolomics analyses, we confirmed that PD fluid induces metabolic reprogramming, characterized as hyperglycolysis, in mouse peritoneum. We found that transforming growth factor β1 (TGF-β1) can substitute for PD fluid to stimulate hyperglycolysis, suppressing mitochondrial respiration in mesothelial cells. Blockade of hyperglycolysis with 2-deoxyglucose (2-DG) inhibited TGF-β1–induced profibrotic cellular phenotype and peritoneal fibrosis in mice. We developed a triad of adeno-associated viruses that overexpressed microRNA-26a and microRNA-200a while inhibiting microRNA-21a to target hyperglycolysis and fibrotic signaling. Intraperitoneal injection of the viral triad inhibited the development of peritoneal fibrosis induced by PD fluid in mice. We conclude that hyperglycolysis is responsible for MMT and peritoneal fibrogenesis, and this aberrant metabolic state can be corrected by modulating microRNAs in the peritoneum. These results could provide a therapeutic strategy to combat peritoneal fibrosis.

Epigenetic mechanisms and metabolic reprogramming in fibrogenesis: dual targeting of G9a and DNMT1 for the inhibition of liver fibrosis

“…Metabolic reprogramming is emerging as a critical event in fibrogenic activation across different tissue types. [4,5,35,36] Therefore, we examined the effects of CM272 on oxygen consumption rate (OCR; a representation of mitochondrial activity) and the extracellular acidification rate (ECAR; a surrogate for glycolytic rate) in LX2 cells treated with TGF. As recently reported we found that TGF reduced OCR and increased ECAR, [36] however these effects were attenuated by CM272 ( Fig.…”

Transforming growth factor–β in tissue fibrosis

“…Recent studies have suggested that TGF-β-driven activation of fibroblasts may involve accentuation of metabolic activity. TGF-β stimulation induces metabolic reprogramming in fibroblasts and accentuates glycolytic pathways (Si et al, 2019), inducing expression and activation of hexokinase-2 (Yin et al, 2019). Hexokinase-2 activation has been shown to stimulate myofibroblast conversion while also inducing ECM gene synthesis (Yin et al, 2019).…”

TGF-β1 is a regulator of the pyruvate dehydrogenase complex in fibroblasts

“…More recently we have also seen that metabolic reprograming plays an essential role in the differentiation and cell fate commitment of pluripotent stem cells 5 . Likewise there is also mounting evidence of a reprogramming of cellular metabolism in various forms of fibrosis [6][7][8] , including myofibroblast-like cells 8,9 in keloids 10 , hepatic 11,12 , lung 8 and perioteneal 13 fibrosis. Although TGF-β1 is a specific driver in many cases [11][12][13] , the molecular events underpinning these global changes remain ill-defined.…”