Isorhamnetin ameliorates cisplatin-induced acute kidney injury in mice by activating SLPI-mediated anti-inflammatory effect in macrophage

Abstract

Objective

Isorhamnetin (IH) has been reported to have significant anti-inflammatory effects in various diseases, but its role and mechanism in AKI remain unclear. This study aimed to explore the potential role and mechanism of isorhamnetin in inhibiting macrophage related inflammation and improving AKI injury.

Methods

We established an AKI mouse model by intraperitoneal injection of cisplatin in vivo, and constructed an inflammatory cell model by stimulating RAW264.7 cells with LPS. Creatinine and urea nitrogen were measured to evaluate the changes of renal function in AKI mice. The changes of renal pathological structure were observed by H&E staining. The inflammatory factor-related proteins and RNA expression levels were detected by Western blot and real time PCR.

Results

Isorhamnetin protected the kidney from cisplatin induced AKI and significantly inhibited the mRNA and protein levels of inflammatory cytokines (IL-1β, IL-6, and TNF-α) both in AKI kidney and LPS-stimulated RAW264.7 cells. Interestingly, the data also demonstrated that isorhamnetin significantly upregulated the expression of secretory leukocyte peptidase inhibitor (SLPI), an anti-inflammatory factor, in AKI kidney and LPS-stimulated macrophages, as well as inhibited the M1 macrophage and activated M2 macrophage in vitro. Blocking of SLPI by siRNA activated Mincle-associated inflammatory signaling in macrophages, and the inhibitory effect of isorhamnetin on inflammation was significantly attenuated.

Conclusion

Isorhamnetin inhibits macrophage inflammation and protects kidney in AKI may be related to downregulating Mincle/Syk/NF-κB-maintained macrophage phenotype by activating SLPI.

Keywords:

• Isorhamnetin
• AKI
• SLPI
• kidney
• mincle

Author contributions

Li Wang and Rui-zhi Tan designed the experiments; Jian Jia and Yu-qing Li performed the experiments; Jian Jia and Rui-zhi Tan writed, reviewed and edited the main text; Rangyue Han and Xia Zhong verified the experimental results; Yin Yan and Ke-huan Xie analyzed the experimental data. All authors agree to be accountable for all aspects of work ensuring integrity and accuracy.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

All data generated or analyzed during this study are included in this article. Further inquiries can be directed to the corresponding author.

Additional information

Funding

This work was supported by the Southwest Medical University Project [2019ZQN099], the Sichuan Science and Technology Program [2022YFS0621], the Southwest Medical University - Affiliated Traditional Medicine Hospital Joint Project [2020XYLH-080], the Construction Project of Sichuan Provincial Key Laboratory of Medicine [2018#53], the Luzhou science and technology project [2020-JYJ-56], [2021-RCM-118] and the Luzhou Municipal - Southwest Medical University Joint Special Grant for the Introduction of High-level Talents (Lan Hui-Yao Team).