ABSTRACT
Sepsis-induced uncontrolled systemic inflammatory response syndrome (SIRS) is a critical cause of multiple organ failure. Acute kidney injury (AKI) is one of the most serious complications associated with an extremely high mortality rate in SIRS, and it lacked simple, safe, and effective treatment strategies. Leontopodium leontopodioides (Willd.) Beauv (LLB) is commonly used in traditional Chinese medicine for the treatment of acute and chronic nephritis. However, it remains unclear whether lipopolysaccharide (LPS) affects LPS-induced AKI. To identify the molecular mechanisms of LLB in LPS-induced HK-2 cells and mice, LLB was prepared by extraction with 70% methanol, while a lipopolysaccharide (LPS)-induced HK-2 cell model and an AKI model were established in this study. Renal histopathology staining was performed to observe the morphology changes. The cell supernatant and kidney tissues were collected for determining the levels of inflammatory factors and protein expression by ELISA, immunofluorescence, and Western blot. The results indicated that LLB significantly reduced the expression of IL-6 and TNF-α in LPS-induced HK-2 cells, as well as the secretion of IL-6, TNF-α, and IL-1β in the supernatant. The same results were observed in LPS-induced AKI serum. Further studies revealed that LLB remarkably improved oxidative stress and apoptosis based on the content of MDA, SOD, and CAT in serum and TUNEL staining results. Notably, LLB significantly reduced the mortality due to LPS infection. Renal histopathology staining results supported these results. Furthermore, immunofluorescence and Western blot results confirmed that LLB significantly reduced the expression of the protein related to the NF-κB signaling pathway and NLRP3, ASC, and Caspase-1 which were significantly increased through LPS stimulation. These findings clearly demonstrated the potential use of LLB in the treatment of AKI and the crucial role of the NF-κB/NLRP3 pathway in the process through which LLB attenuates AKI induced by LPS.
Subject(s)
Animals , Mice , NF-kappa B/metabolism , Lipopolysaccharides/adverse effects , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Tumor Necrosis Factor-alpha/metabolism , Interleukin-6/metabolism , Acute Kidney Injury/metabolism , Kidney , Systemic Inflammatory Response Syndrome/pathologyABSTRACT
OBJECTIVE：To study the improvement effect and possible mechanism of Leontopodium leontopodioides combined with Astragalus membranaceus on the renal function of mesangial proliferative glomerulonephritis （MsPGN） model rats. METHODS：Totally 85 rats were randomly divided into sham operation group （n＝10）and modeling group （n＝75）. Sham operation group underwent sham operation ，and MsPGN model was induced by immunological method [Freund ’s adjuvant+BSA + lipopolysaccharide（LPS）] in modeling group. After successfully modeling ，70 rats were randomly divided into model group ，L. leontopodioides+A. membranaceus high-dose，medium-dose and low-dose groups （4.05，2.03，1.02 g/kg，by total crude drug ），L. leontopodioides alone group （2.70 g/kg，by crude drug ），Tripterygium glycosides tablet group （positive control 1，0.02 g/kg）， Lotensin tablet group （positive control 2，0.02 g/kg），with 10 rats in each group. Sham operation group and model group were given constant volume of normal saline intragastrically ； administration groups were given relevant drug solution intrasgastrcially at a volume of 15 mL/kg，once a day ，for consecutive 5 weeks. At last administration ，24 h urinary lnzyxyqy2003@163.com protein，urine creatinine and serum creatinine were determined in rats. The right kidney was weighed ，and HE staining was used to observe the pathomorpholog y changes of renal tissue. Immunohistochemistry was used to detect the protein expression of NF-κB p65 in renal tissue. Western blotting assay was used to determine the protein expressions of NF-κB p65，IκBα，ERK，p-ERK and p 38 MAPK in renal tissue. RESULTS ：Compared with sham operation group ，right kidney weight ，24 h urine protein and serum creatinine levels ，protein expressions of NF-κB p65， p-ERK and p 38 MAPK in renal tissue were increased significantly in model group （P＜0.05 or P＜0.01）；the level of urine creatinine and protein expression of IκBα in renal tissue were decreased significantly（P＜0.05 or P＜0.01）；there were obvious glomerular hypertrophy ，diffuse increase of mesangial cells ，necrosis of renal tubules and other pathomorphological changes in renal tissue. Compared with model group ，right kidney weight and serum creatinine level were decreased significantly in L. leontopodioides alone group （P＜0.05），while urine creatinine level was increased significantly （P＜0.05），but there was no statistical significance in the level of 24 h urine protein （P＞0.05）；the right kidney weight ，24 h urine protein ，serum creatinine level and protein expression levels of NF-κB p65，p-ERK and p38 MAPK in renal tissue were decreased significantly in L. leontopodioides+A. membranaceus high-dose group （P＜0.05），while the urine creatinine level and protein expression level of IκBα in renal tissue were increased significantly （P＜0.05 or P＜0.01）；there was no statistical significance in above indexes in L. leontopodioides+A. membranaceus medium-dose，low-dose groups （P＞0.05）；pathological changes of renal tissue were improved to different extents in administration groups ，especially in L. leontopodioides +A. membranaceus high-dose group. CONCLUSIONS ： High dose of L. leontopodioides +A. membranaceus can improve renal function of MsPGN model rats by inhibiting MAPK/NF-κB signal pathway.
ABSTRACT
The present study was designed to establish a suitable assay to explore CCR2b receptor antagonists from the natural products of Artemisia rupetris and Leontopodium leontopodioides. An aequorin assay was developed as a cell-based assay suitable for 384-well microplate and used for screening CCR2b receptor antagonists from natural products. Through establishing suitable conditions, the assay was shown to be suitable for screening of CCR2b receptor antagonists. Seven compounds were identified in preliminary screening. Five of them showed evident dose-response relationship in secondary screening. The structure-activity relationship study suggested that 7-position hydroxyl group of flavonoids was necessary, a polar group should be introduced on the 3-position, and the substituents on 2-position benzene ring of flavonoids have little influence on the potentency of the inhibition activity on CCR2b receptor. The ortho-position dihydroxyl structure in quinic acid compounds may be important. In conclusion, Compounds HR-1, 5, 7, and AR-20, 35 showed activity as antagonist of CCR2b receptor, which shed lights on the development of novel drugs as CCR2b receptor antagonists for preventing inflammation related diseases.