Mees Ian, Prat-Duran Judit, Comerma-Steffensen Simon, Simonsen Ulf, Pinilla Estéfano, Buus Niels Henrik
Department of Biomedicine, Health, Aarhus University, 8000 Aarhus C, Denmark.
Department of Biomedical Sciences/Animal Physiology, Veterinary Sciences, Central University of Venezuela, Maracay 79CQ+VH3, Venezuela.
Int J Mol Sci. 2025 Jun 14;26(12):5724. doi: 10.3390/ijms26125724.
The enzyme transglutaminase 2 (TG2) has an open conformation with transamidase activity which crosslinks matrix proteins contributing to fibrosis development. LDN-27219 promotes the closed conformation of TG2, which can enhance vasodilation, but its effects in renal tissue are unknown. We investigated whether LDN-27219 treatment affects albuminuria and markers of renal fibrosis as well as ex vivo vasodilatation. Male C57BL/6 mice (n = 48) underwent unilateral nephrectomy plus insertion of a deoxycorticosterone acetate pellet (DOCA group) or nephrectomy only (sham group). Both groups were randomized to intraperitoneal treatment with either LDN-27219 (8 mg/kg twice daily) or vehicle for 2 weeks. Urine albumin excretion was evaluated by metabolic cages. Kidney tissue fibrosis markers were assessed by qPCR and Western blotting, while the TG2 conformational state was evaluated using native gel electrophoresis. Collagen staining was performed using Picrosirius red and quantified under circularly polarized light. Mesenteric arteries were mounted in wire myographs for evaluation of vasorelaxation. DOCA mouse developed significant albuminuria ( < 0.001 vs. sham), but neither TG2 mRNA nor protein expression was upregulated in the kidney. However, the relative amount of TG2 in the closed conformation was higher in DOCA mice. LDN-27219 did not affect albuminuria, but LDN-27219-treated DOCA mice showed less urine production and less collagen staining than vehicle-treated DOCA mice. LDN-27219 did not affect TG2 mRNA or TG2 protein expression or mRNA of fibrosis markers. LDN-27219-treated mice had enhanced vasorelaxation to the nitric oxide donor sodium nitroprusside. In conclusion, LDN-27219 treatment in the one-kidney DOCA-salt model did not affect renal TG2 mRNA and protein expression or albuminuria but still exerted beneficial effects in terms of reduced kidney fibrosis and urine production in addition to enhanced vasodilatation.
转谷氨酰胺酶2（TG2）具有开放构象并带有转酰胺酶活性，该活性可使基质蛋白交联，从而促进纤维化发展。LDN - 27219可促使TG2转变为封闭构象，这能够增强血管舒张，但它在肾组织中的作用尚不清楚。我们研究了LDN - 27219治疗是否会影响蛋白尿、肾纤维化标志物以及体外血管舒张。雄性C57BL/6小鼠（n = 48）接受单侧肾切除术并植入醋酸脱氧皮质酮微丸（DOCA组）或仅进行肾切除术（假手术组）。两组均随机接受腹腔注射LDN - 27219（8 mg/kg，每日两次）或赋形剂治疗2周。通过代谢笼评估尿白蛋白排泄情况。通过qPCR和蛋白质印迹法评估肾组织纤维化标志物，同时使用非变性凝胶电泳评估TG2的构象状态。使用天狼星红进行胶原染色，并在圆偏振光下进行定量分析。将肠系膜动脉安装在血管张力描记仪中以评估血管舒张情况。DOCA小鼠出现了显著的蛋白尿（与假手术组相比，< 0.001），但肾组织中TG2的mRNA和蛋白表达均未上调。然而，DOCA小鼠中处于封闭构象的TG2相对量更高。LDN - 27219对蛋白尿没有影响，但与接受赋形剂治疗的DOCA小鼠相比，接受LDN - 27219治疗的DOCA小鼠尿量更少且胶原染色更少。LDN - 27219不影响TG2的mRNA或蛋白表达，也不影响纤维化标志物的mRNA。接受LDN - 27219治疗的小鼠对一氧化氮供体硝普钠的血管舒张反应增强。总之，在单肾DOCA - 盐模型中，LDN - 27219治疗不影响肾组织中TG2的mRNA和蛋白表达或蛋白尿，但除了增强血管舒张外，在减少肾纤维化和尿量方面仍发挥了有益作用。
