Page 21 - 南京医科大学自然版

第44卷第10期 南京医科大学学报（自然科学版）
2024年10月 Journal of Nanjing Medical University（Natural Sciences） ·1337 ·

·基础研究·

瘦素激活PI3K/AKT信号促进小鼠心肌细胞衰老的初步研究

彭明玉，刘倩颖，沈丹丹，吕宏祥 *
南京医科大学附属江宁医院检验科，江苏 南京 211100

［摘 要］ 目的：探讨瘦素在小鼠心肌细胞（mouse cardiomyocyte，MCM）衰老中的作用及调控机制。方法：qPCR检查瘦素刺激
后 MCM 中衰老相关指标 p16、p21 和衰老相关分泌表型（senescence⁃associated secretory phenotype，SASP）的 mRNA 表达量；
Western blot检测p16、p21、γ⁃H2AX、PI3K、AKT、p⁃PI3K和p⁃AKT的蛋白表达量；β⁃半乳糖苷酶染色检测MCM衰老。PI3K抑制
剂（LY294002）预处理2 h后再给予瘦素刺激，qPCR和Western blot 检测p16和p21的mRNA和蛋白表达水平；qPCR检查SASP
的 mRNA 表达水平；β⁃半乳糖苷酶染色检测 MCM 衰老。结果：瘦素刺激 MCM 后，p16 和 p21 的 mRNA 及蛋白表达增加，同时
γ⁃H2AX的蛋白水平也显著上升，SASP［白介素（interleukin，IL）⁃1β、肿瘤坏死因子（tumor necrosis factor，TNF）⁃α、IL⁃6和单核细
胞趋化蛋白（monocyte chemoattractant protein，MCP）⁃1）］的mRNA水平上调，PI3K/AKT信号通路的蛋白磷酸化水平升高，β⁃半
乳糖苷酶染色显示MCM发生衰老。PI3K抑制剂预处理2 h后，p16和p21的mRNA和蛋白水平明显降低，同时γ⁃H2AX的蛋白
水平也显著下调；SASP mRNA水平降低；β⁃半乳糖苷酶染色显示MCM衰老缓解。结论：瘦素通过活化PI3K/AKT信号通路分
泌SASP（IL⁃1β、TNF⁃α、IL⁃6和MCP⁃1）调控MCM衰老的发展进程。
［关键词］ 瘦素；心肌细胞；细胞衰老
［中图分类号］ R329.2 ［文献标志码］ A ［文章编号］ 1007⁃4368（2024）10⁃1337⁃07
doi：10.7655/NYDXBNSN240432

Activation of PI3K/AKT signaling pathway by leptin promotes MCM senescence of mouse
cardiomyocytes

PENG Mingyu，LIU Qianying，SHEN Dandan，LÜ Hongxiang *
Department of Laboratory Medicine，Jiangning Hospital Affiliated to NanjngNanjing Medical University，Nanjing
211100，China

［Abstract］ Objective：To explore the role and regulation mechanism of leptin in senescence of mouse cardiomyocytes（MCM）.
Methods：The mRNA expression levels of senescence related indicators p16，p21，and senescence⁃associated secretory phenotype
（SASP）in leptin stimulated MCM were examined by qPCR；the protein expressions of p16，p21，γ⁃H2AX，PI3K，AKT，p⁃PI3K，and
p⁃AKT were detected by Western blot；the senescence of MCM was detected by β⁃galactosidase staining. PI3K inhibitor（LY294002）
was pretreated for 2 h and then stimulated with leptin，the mRNA and protein levels of p16 and p21 were detected by qPCR and
Western blot；the mRNA levels of SASP were examined by qPCR；MCM senescence was detected by β⁃galactosidase staining. Results：
In MCM stimulated by leptin，the mRNA and protein levels of p16 and p21，as well as the protein level of γ⁃H2AX increased，the
mRNA levels of SASP［（interleukin，IL）⁃1β，tumor necrosis factor（TNF）⁃α、IL⁃6，monocyte chemoattractant protein（MCP）⁃1］were up
⁃regulated，the phosphorylation levels of proteins in PI3K/AKT signaling pathway increased；and β⁃galactosidase staining showed the
senescence of MCM. When pretreated with PI3K inhibitor for 2 h，the mRNA and protein levels of p16 and p21，as well as the protein
level of γ ⁃ H2AX were down ⁃ regulated，and the expressions of SASP mRNA were down ⁃ regulated，the senescence of MCM was
alleviated. Conclusion：Leptin regulates the progression of MCM senescence by activating PI3K/AKT signaling pathway and promoting
SASP（IL⁃1β，TNF⁃α，IL⁃6 and MCP⁃1）secretion.
［Key words］ leptin；cardiomyocyte；cellular senescence ［J Nanjing Med Univ，2024，44（10）：1337⁃1343］

［基金项目］ 江苏卫生健康职业学院院级科研项目（JKC2021077）；南京医科大学附属江宁医院医学科研项目（JNYYZXKY202304）；
国家自然科学基金（82101851）
∗
通信作者（Corresponding author），E⁃mail：hero_0620@163.com