Targeting GATA1 and p2x7r Locus Binding in Spinal Astrocytes Suppresses Chronic Visceral Pain by Promoting DNA Demethylation / 神经科学通报·英文版

Irritable bowel syndrome is a gastrointestinal disorder of unknown etiology characterized by widespread, chronic abdominal pain associated with altered bowel movements. Increasing amounts of evidence indicate that injury and inflammation during the neonatal period have long-term effects on tissue structure and function in the adult that may predispose to gastrointestinal diseases. In this study we aimed to investigate how the epigenetic regulation of DNA demethylation of the p2x7r locus guided by the transcription factor GATA binding protein 1 (GATA1) in spinal astrocytes affects chronic visceral pain in adult rats with neonatal colonic inflammation (NCI). The spinal GATA1 targeting to DNA demethylation of p2x7r locus in these rats was assessed by assessing GATA1 function with luciferase assay, chromatin immunoprecipitation, patch clamp, and interference in vitro and in vivo. In addition, a decoy oligodeoxynucleotide was designed and applied to determine the influence of GATA1 on the DNA methylation of a p2x7r CpG island. We showed that NCI caused the induction of GATA1, Ten-eleven translocation 3 (TET3), and purinergic receptors (P2X7Rs) in astrocytes of the spinal dorsal horn, and demonstrated that inhibiting these molecules markedly increased the pain threshold, inhibited the activation of astrocytes, and decreased the spinal sEPSC frequency. NCI also markedly demethylated the p2x7r locus in a manner dependent on the enhancement of both a GATA1-TET3 physical interaction and GATA1 binding at the p2x7r promoter. Importantly, we showed that demethylation of the p2x7r locus (and the attendant increase in P2X7R expression) was reversed upon knockdown of GATA1 or TET3 expression, and demonstrated that a decoy oligodeoxynucleotide that selectively blocked the GATA1 binding site increased the methylation of a CpG island in the p2x7r promoter. These results demonstrate that chronic visceral pain is mediated synergistically by GATA1 and TET3 via a DNA-demethylation mechanism that controls p2x7r transcription in spinal dorsal horn astrocytes, and provide a potential therapeutic strategy by targeting GATA1 and p2x7r locus binding.

Epigenética de la enfermedad renal / Epigenetics of Renal Disease

Para nosotros generar una defnición determinada y entendible necesitamos de elementos de comparación; así, por ejemplo, para nosotros "entender "que es el "día" necesariamente debemos conocer que es la "noche". Esta antítesis por contraste nos grafca estos dos conceptos y nos lleva al ámbito de la "certidumbre" y es por esto que un "eclipse total" en pleno día se presenta como un fenómeno de ruptura de lo conocido como "cierto" desde que nacemos y que NO admite contradicción pues es ya parte de nuestra "conciencia genética" ; es decir, un evento externo de la vida real (día-noche) condicionado a eventos internos (genéticos) generando ­ en el caso del ejemplo ­ el "ritmo circadiano", "envejecimiento celular", "esperanza de vida al nacer" , "cronobiología".

For us to generate a definition determined and understandable we need elements of comparison; Thus, for example, for us to "understand" what "day" is, we must necessarily know what is the "night". This contrast antithesis we graph these two concepts and we leads to the field of "certainty" and this is why a "total eclipse" in broad daylight it is presented as a phenomenon of rupture of the known as "true" since we were born and that does NOT admit contradiction it is already part of our "genetic consciousness"; that is, an event external real life (day-night) conditioned to internal events (genetic) generating - in the case from the example - the "circadian rhythm", "Cell aging", "hope of life at birth "," chronobiology ".

Regulation of DNA demethylation of STAT3 promoter in CD4+ T cells from aGVHD patients by HMGB1/GADD45A / 中南大学学报(医学版)

To study the molecular mechanism for DNA hypomethylation of STAT3 promoter in CD4+ T cells from acute graft-versus-host disease (aGVHD) patients.
 Methods: We collected CD4+ T cells from peripheral blood of 42 patients who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) from HLA-identical sibling donors. GADD45A expression level in CD4+ T cells was measured by real-time PCR and Western blot. The binding level between HMGB1 and GADD45A in CD4+ T cells was analyzed by co-immunoprecipitation, while the binding levels of HMGB1/GADD45A with STAT3 promoter were detected by chromatin immunoprecipitation-quantitative real-time PCR (ChIP-qPCR). After overexpression of HMGB1 and knockdown of GADD45A in normal CD4+ T cells, STAT3 expression and DNA methylation were measured by Western blot and bisulfite sequencing PCR, respectively.
 Results: GADD45A expression was significantly up-regulated in patients with aGVHD compared with that in the patients without aGVHD. More HMGB1-GADD45A complexes were found in CD4+ T cells from patients with aGVHD compared with that in patients without aGVHD. The bindings of HMGB1/GADD45A with STAT3 promoter were significantly increased, and the binding levels of HMGB1/GADD45A were negatively correlated with STAT3 promoter DNA methylation. The expression of STAT3 was significantly reduced and the DNA methylation of STAT3 promoter was significantly increased in CD4+ T cells with overexpression of HMGB1 and knockdown of GADD45A compared with CD4+ T cells only with overexpression of HMGB1.
 Conclusion: The increased expression of HMGB1/GADD45A plays an importent role in STAT3 promoter DNA hypomethylation, thereby promoting STAT3 expression in CD4+ T cells from aGVHD patients.