Inhibition of glutaminolysis alleviates myocardial fibrosis induced by angiotensin II / 生理学报

The present study was aimed to investigate the role and mechanism of glutaminolysis of cardiac fibroblasts (CFs) in hypertension-induced myocardial fibrosis. C57BL/6J mice were administered with a chronic infusion of angiotensin II (Ang II, 1.6 mg/kg per d) with a micro-osmotic pump to induce myocardial fibrosis. Masson staining was used to evaluate myocardial fibrosis. The mice were intraperitoneally injected with BPTES (12.5 mg/kg), a glutaminase 1 (GLS1)-specific inhibitor, to inhibit glutaminolysis simultaneously. Immunohistochemistry and Western blot were used to detect protein expression levels of GLS1, Collagen I and Collagen III in cardiac tissue. Neonatal Sprague-Dawley (SD) rat CFs were treated with 4 mmol/L glutamine (Gln) or BPTES (5 μmol/L) with or without Ang II (0.4 μmol/L) stimulation. The CFs were also treated with 2 mmol/L α-ketoglutarate (α-KG) under the stimulation of Ang II and BPTES. Wound healing test and CCK-8 were used to detect CFs migration and proliferation respectively. RT-qPCR and Western blot were used to detect mRNA and protein expression levels of GLS1, Collagen I and Collagen III. The results showed that blood pressure, heart weight and myocardial fibrosis were increased in Ang II-treated mice, and GLS1 expression in cardiac tissue was also significantly up-regulated. Gln significantly promoted the proliferation, migration, mRNA and protein expression of GLS1, Collagen I and Collagen III in the CFs with or without Ang II stimulation, whereas BPTES significantly decreased the above indices in the CFs. α-KG supplementation reversed the inhibitory effect of BPTES on the CFs under Ang II stimulation. Furthermore, in vivo intraperitoneal injection of BPTES alleviated cardiac fibrosis of Ang II-treated mice. In conclusion, glutaminolysis plays an important role in the process of cardiac fibrosis induced by Ang II. Targeted inhibition of glutaminolysis may be a new strategy for the treatment of myocardial fibrosis.

Dynamic monitoring of γδT cells in murine cornea in vivo using two-photon laser scanning microscopy / 眼科新进展

Objective To compare the removal efficiency of γδT cells between cornea and ear skin and develop an alternative method for dynamic monitoring of γδT cells in mouse cornea in vivo using 2-photon laser scanning microscopy.Methods The γδT cells in mouse ear skin were monitored before and after antibody neutralization,and the mice corneas were excised and stained for counting γδT cells at 6 h,12 h,24 h after antibody neutralization by using 2-photon laser scanning microscopy,followed by comparison of the removal efficiency of γδT cells between the cornea and ear skin.Results The γδT cells in normal mouse cornea were often distributed in the limbal epithelium and superficial stromal layer.The irregular morphology of γδT cells in the epithelial layer was often accompanied by protuberances,while the stromal γδT cells were mostly round or oval and the number of cells was approximately 27 ± 4.After antibody neutralization,the number of γδT cells in the cornea of mice gradually decreased,and the number of cells at 6 h,12 h and 24 h was significantly lower than that of before depletion (P =0.03,0.00,0.00),and the removal efficiencies were 48％,78％,and 96％,respectively.The γδT cells in ear skin of the normal mice were ellipse or stellate with cell processes and they were located in epidermal layer,and the cell number was about 60 ± 9.After antibody neutralization,the number of γδT cells were significantly reduced at 6 h,12 h and 24 h compared with before depletion (P =0.000,0.000,0.000) and the removal efficiency were 43％,72％ and 95％,respectively.Conclusion The number of γδT cells in the cornea and ear skin is gradually decreased after antibody neutralization,and their removal efficiency is consistent with time.Therefore,monitoring the γδT cells in the mouse ear skin is an ideal alternative to dynamically monitoring the changes in the number of γδT cells in the cornea in vivo.