Wang Chenran, Mao Leilei, He Miao, Zhang Jia, Huang Yichen, Zhang Yue, Xu Jing, Huang Shaoqiang, Gao Yanqin
Department of Anesthesiology of Eye & Ent Hospital, Department of Anesthesiology of Obstetrics & Gynecology Hospital, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, and Institutes of Brain Science, Fudan University, Shanghai, China.
CNS Neurosci Ther. 2025 Feb;31(2):e70257. doi: 10.1111/cns.70257.
Caloric restriction is a health-promoting lifestyle that has been reported to protect both white and gray matter in cases of ischemic stroke. This study will explore the underlying mechanism of restricted feeding (RF) and provide a theoretical basis for precise clinical treatment of stroke.
In this study, we pretreated C57BL/6J mice with 70% RF for a continuous 28-day period prior to 60 min of transient focal cerebral ischemia (tFCI). Histological staining, diffusion tensor imaging (DTI), and behavioral assessments were used to assess RF's neuroprotection following tFCI. Immunofluorescence staining, quantitative real-time PCR, and flow cytometry were conducted to evaluate brain inflammation post-tFCI. Western blot, immunofluorescence staining, tracers, and electric microscopy were used to assess the blood-brain barrier (BBB) integrity. Peripheral neutrophils were cleared by administrating an anti-Ly6G antibody.
Initially, DTI, NeuN staining, and a batch of behavioral tests verified that RF significantly mitigated both gray/white matter injury and neurological deficits in the short- and long-term following tFCI. RF mice showed more anti-inflammatory microglia in their brains, along with reduced inflammatory cytokines, and chemokines. Interestingly, RF significantly reduced the neutrophils and macrophage infiltration. Subsequently, we observed that RF mice exhibited better BBB integrity following tFCI, with reduced neutrophil infiltration and matrix metalloprotein-9 release. Furthermore, the clearance of neutrophils with anti-Ly6G antibody in ad libitum feeding mice (LF-Ly6G) elicited comparable neuroprotective effects to those observed in RF, including improvements in neurological deficits, reductions in infarct volume, and mitigation of BBB damage.
In summary, our findings suggest that RF maintains the BBB integrity following ischemic stroke at least partially by reducing neutrophil infiltration, thereby alleviating both neurological and histological impairments.
热量限制是一种促进健康的生活方式，据报道，在缺血性中风病例中，它对灰质和白质均有保护作用。本研究将探索限时喂养（RF）的潜在机制，并为中风的精准临床治疗提供理论依据。
在本研究中，我们在对C57BL/6J小鼠进行60分钟短暂性局灶性脑缺血（tFCI）之前，先对其进行连续28天的70%热量限制预处理。采用组织学染色、扩散张量成像（DTI）和行为评估来评估tFCI后RF的神经保护作用。进行免疫荧光染色、定量实时PCR和流式细胞术以评估tFCI后的脑炎症。采用蛋白质免疫印迹法、免疫荧光染色、示踪剂和电子显微镜来评估血脑屏障（BBB）的完整性。通过给予抗Ly6G抗体清除外周中性粒细胞。
最初，DTI、NeuN染色和一系列行为测试证实，RF在tFCI后的短期和长期内均能显著减轻灰质/白质损伤和神经功能缺损。RF小鼠大脑中显示出更多的抗炎小胶质细胞，同时炎症细胞因子和趋化因子减少。有趣的是，RF显著减少了中性粒细胞和巨噬细胞的浸润。随后，我们观察到RF小鼠在tFCI后表现出更好的BBB完整性，中性粒细胞浸润和基质金属蛋白酶-9释放减少。此外，在自由进食小鼠（LF-Ly6G）中用抗Ly6G抗体清除中性粒细胞所产生的神经保护作用与RF中观察到的相当，包括神经功能缺损的改善、梗死体积的减小和BBB损伤的减轻。
总之，我们的研究结果表明，RF至少部分通过减少中性粒细胞浸润来维持缺血性中风后的BBB完整性，从而减轻神经和组织学损伤。
