Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA.
Center for Blood-Brain Barrier Research, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA.
Int J Mol Sci. 2019 Aug 29;20(17):4225. doi: 10.3390/ijms20174225.
Tobacco smoking (TS) is one of the most addictive habit sand a main public health hazards, impacting the vascular endothelium through oxidative stress (OS) stimuli, exposure to nicotine, and smoking-induced inflammation in a dose-dependent manner. Increasing evidence also suggested that TS increases glucose intolerance and the risk factor of developing type-2 diabetes mellitus (2DM), which, along with TS, is connected to blood-brain barrier (BBB) injuries, and heightens the risk of cerebrovascular disorders. Although the exact mechanism of rosiglitazone (RSG) is unknown, our previous in vitro work showed how RSG, an oral anti-diabetic drug belonging to the family of thiazolidinedione class, can protect BBB integrity through enhancement of nuclear factor erythroid 2-related factor (Nrf2) activity. Herein, we have validated the protective role of rosiglitazone against TS-induced BBB impairment in vivo. Our results revealed that RSG as a peroxisome proliferator-activated receptor gamma (PPARγ), activates counteractive mechanisms primarily associated with the upregulation of Nrf2 and PPARγ pathways which reduce TS-dependent toxicity at the cerebrovascular level. In line with these findings, our results show that RSG reduces inflammation and protects BBB integrity. In conclusion, RSG offers a novel and promising therapeutic application to reduce TS-induced cerebrovascular dysfunction through activation of the PPARγ-dependent and/or PPARγ-independent Nrf2 pathway.
吸烟(TS)是最容易上瘾的习惯之一,也是主要的公共健康危害之一,通过氧化应激(OS)刺激、尼古丁暴露和吸烟引起的炎症,以剂量依赖的方式影响血管内皮。越来越多的证据还表明,TS 会增加葡萄糖耐量和 2 型糖尿病(2DM)的发病风险,2DM 与 TS 一起与血脑屏障(BBB)损伤有关,并增加脑血管疾病的风险。虽然罗格列酮(RSG)的确切机制尚不清楚,但我们之前的体外研究表明,RSG 是一种属于噻唑烷二酮类的口服抗糖尿病药物,如何通过增强核因子红细胞 2 相关因子(Nrf2)的活性来保护 BBB 的完整性。在此,我们验证了 RSG 对体内 TS 诱导的 BBB 损伤的保护作用。我们的结果表明,RSG 作为过氧化物酶体增殖物激活受体γ(PPARγ),激活了主要与 Nrf2 和 PPARγ 途径的上调相关的拮抗性机制,从而减少了脑血管水平上 TS 依赖性毒性。与这些发现一致,我们的结果表明,RSG 减少了炎症并保护了 BBB 的完整性。总之,RSG 通过激活 PPARγ 依赖性和/或非依赖性 Nrf2 途径,为减少 TS 诱导的脑血管功能障碍提供了一种新颖而有前途的治疗应用。