Aims

The lack of effective treatments for ischemic stroke is concerning. Here, we aimed to examine the protective effects of sestrin2 in ischemic stroke and determine the mechanism by which sestrin2 attenuates cerebral injuries.

Main methods

Ischemic stroke was induced in Sprague-Dawley rats using a photothrombotic ischemia (PTI) model. After sestrin2 was overexpressed or silenced, neurological deficits and brain infarction were evaluated. Cerebral angiogenesis and the expression of related proteins were examined by Western blotting and immunofluorescence. The interaction between p62 and Keap1 was measured by coimmunoprecipitation (CoIP) and an in situ proximity ligation assay (PLA).

Key findings

The overexpression of sestrin2 was found to improve the neurological function of rats 10 days after PTI and to reduce the infarct volume and brain edema in rats 10 days after PTI. It was shown that upregulating sestrin2 enhanced the relative immunofluorescence intensity of CD34, CD31 and DCX. Sestrin2 overexpressionalso increased the number and total length of CD34 and CD31 positive vessels and the expression of nuclear and total Nrf2, HO-1, VEGF and p62. However, downregulating sestrin2 induced almost the opposite results. Furthermore, we demonstrated that sestrin2 increased the interaction between p62 and Keap1.

Significance

Based on our data, sestrin2 may promote angiogenesis by activating the Nrf2 pathway through increasing the interaction between p62 and Keap1 via upregulating p62 expression.

中文翻译：

---

Sestrin2 通过调节大鼠光血栓性卒中后 p62 和 Keap1 之间的相互作用激活 Nrf2 促进血管生成以减轻脑损伤。

目标

缺血性中风缺乏有效的治疗方法令人担忧。在这里，我们旨在检查 sestrin2 在缺血性中风中的保护作用，并确定 sestrin2 减轻脑损伤的机制。

主要方法

使用光血栓形成缺血 (PTI) 模型在 Sprague-Dawley 大鼠中诱导缺血性中风。在 sestrin2 过表达或沉默后，评估了神经功能缺损和脑梗塞。采用蛋白质印迹法和免疫荧光法检测脑血管生成和相关蛋白的表达。p62 和 Keap1 之间的相互作用通过免疫共沉淀 (CoIP) 和原位邻近连接测定 (PLA) 测量。

主要发现

发现 sestrin2 的过表达可改善 PTI 后 10 天大鼠的神经功能，并减少 PTI 后 10 天大鼠的梗塞体积和脑水肿。结果表明，上调 sestrin2 增强了 CD34、CD31 和 DCX 的相对免疫荧光强度。Sestrin2过表达也增加了CD34和CD31阳性血管的数量和总长度以及核和总Nrf2、HO-1、VEGF和p62的表达。然而，下调 sestrin2 诱导了几乎相反的结果。此外，我们证明了sestrin2 增加了p62 和Keap1 之间的相互作用。

意义

根据我们的数据，sestrin2 可能通过上调 p62 表达增加 p62 和 Keap1 之间的相互作用来激活 Nrf2 通路来促进血管生成。