l-Carnitine inhibits the senescence-associated secretory phenotype of aging adipose tissue by JNK/p53 pathway
Senescence-associated secretory phenotype (SASP) plays a role in aging adipose tissue dysfunction by directly promoting chronic inflammation. The JNK/p53 pathway was reported as a potential mechanism that mediates SASP. In this study, we investigated the effects of l-carnitine, an inhibitor of the JNK/p53 pathway in adipose tissue SASP and dysfunction. Young and aging rat were given l-carnitine by gavage. Next, we detected the senescence, cytokines expression, chronic inflammation and insulin resistance of adipose tissue. Additionally, JNK/p53 pathway was estimated. Our results show a significant increase expression of SASP components in the adipose tissue of aging rats compared to young rats. Further, we found that infiltration of immune cells and the expression of pro-inflammatory cytokines were enhanced in aging adipose tissue while insulin signaling activity was reduced in aging adipose tissue. Interestingly, l-carnitine markedly reduced the expression of SASP factors. l-Carnitine could significantly reduce chronic inflammation, improving insulin resistance. Further, l-carnitine inhibited SASP by inhibiting JNK/p53 pathway. l-Carnitine inhibited SASP by JNK/p53 pathway and attenuated adipose tissue dysfunction of aging.
KeywordsAging SASP Adipose tissue l-Carnitine
This work was supported by the research Grants from the National Natural Science Foundation of China (81702194, 81600633, 81670411, 81570400, 81470560, 81471036), Key research and development program of Shandong Province (2018GSF118002, 2018GSF118017, 2017GSF18156), the Natural Science Foundation of Shandong Province (ZR2014HQ037, ZR2017BH023).
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Conflict of interest
The authors declare no competing financial interests.
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