Study on therapeutic effect and its related mechanism of anemoside B4 on ischemia reperfusion injury induced by renal artery and vein ligation in rats / 中国中药杂志

The aim of this paper was to investigate the effect and mechanism of anemoside B4 on renal ischemia reperfusion injury in rats. A total of 50 rats were randomly divided into the model group(NS) and anemoside B4 low-dose(1.25 mg·kg~(-1)), medium-dose(2.5 mg·kg~(-1)) and high-dose(5 mg·kg~(-1)) groups after the right kidney was removed and the left kidney was ligated to make the ischemia reperfusion model. Another 10 rats were selected as sham operation group only for normal control group(NS, received normal saline). Automatic biochemical analyzer was used to measure serum blood urea nitrogen(BUN), creatinine(Cre), cerebrospinal fluid(CSF) and urinemicroalbumin(mALB) levels after 5 days of tail vein injection treament. Total urine protein and total urinary albu-min were calculated and kidney samples were collected. Histopathological changes of renal tissues were observed by PAS staining. Western blot analysis was performed to detect the protein expressions of TLR4 and NF-κB in renal inflammatory factors related to NLRP3 pathway and TLR4/NF-κB pathway. The results showed that the levels of BUN, Cre, urinary total protein and urinary total albumin in the model group were significantly increased(P<0.01), with severe renal tubule injury was serious, manifested by obvious expansion of renal tubules, more serious tubular proteins, and some tubular epithelial cells were exfoliated. At the same time, the expression of inflammatory factors related to NLRP3 pathway and TLR4/NF-κB pathway increased significantly(P<0.01 or P<0.05). The levels of BUN, Cre were reduced in different doses of anemoside B4(P<0.05). The levels of total urinary protein and total urinary albumin were decreased in the low and high dose groups of anemoside B4.The level of total urinary albumin in the high-dose group of anemoside B4 was significantly reduced(P<0.05).Renal tubular injury was alleviated, tubular epithelial cell exfoliation was reduced, and the expression of related inflammatory factors was reduced in different degrees(P<0.01 or P<0.05). This study showed that anemoside B4 could alleviate renal ischemia-reperfusion injury in rats. And its mechanism may be related to the inhibition of inflammatory factors related to response mediated by NLRP3 pathway and TLR4/NF-κB pathway by anemoside B4.

Expression characteristics of inflammatory and apoptosis factors and regulatory effect of anemoside B4 in mice with acute kidney injury / 中国中药杂志

This paper was aimed to observe the effect of anemoside B4(hereinafter referred to as B4) on cisplatin-induced acute kidney injury in mice, and to investigate its possible mechanism in renal protection from inflammation and apoptosis aspects. Mice were divided into normal group, model group, dexamethasone positive group and B4 high, middle and low dose groups(5, 2.5, and 1.25 mg·kg~(-1 )doses). All the other mice groups except normal group were given with tail vein injection of cisplatin(15 mg·kg~(-1)) to induce acute kidney injury models. The drug administration was started on the day of modeling, and lasted for 4 days. After 1 hour of the last injection, orbital blood was collected. After the serum was separated, serum urea nitrogen(BUN), creatinine(Cre), total protein(TP), and albumin(ALB) were tested by using an automatic biochemical analyzer; the changes of kidney pathological morphology were observed by PAS staining; the protein expression levels of inflammatory factors including nucleotide binding oligomerization domain-like receptor(NLRP3), cysteinyl aspartate specific proteinase 1(caspase-1), interleukin-18(IL-18), interleukin-1β(IL-1β), tumor necrosis factor(TNF-α), and interleukin-6(IL-6) and apoptosis factors including p53, caspase-3, cleaved-caspase-3, Bcl-2 associated X protein(Bax), and B-cell lymphoma-2(Bcl-2) were analyzed by Western blot. The results showed that B4 significantly reduced the serum BUN and Cre contents, and alleviated pathological changes in renal tissues, such as the shedding and degeneration of renal tubular epithelial cells, tubulin tubule type. B4 significantly down-regulated the protein expressions of p53, Bax, cleaved-caspase-3 in the kidney and up-regulated the expression of Bcl-2/Bax. In model group, however, no significant up-regulation was observed in the protein expression levels of inflammatory cytokines(NLRP3, pro-caspase-1, IL-18, IL-1β, TNF-α, IL-6). The results suggested that B4 had a certain protective effect on cisplatin-induced acute kidney injury, and could activate p53 signaling pathway related apoptotic factors. B4 renal protective effect was mainly related to the regulation of p53 signaling pathway, while NLRP3 inflammasome and related inflammatory factors had no obvious response in this model.

Study on acute kidney injury model induced by renal ischemia-reperfusion in rats / 中国中药杂志

In this study,in-depth systematic evaluation of rat of acute kidney injury(AKI) caused by renal arteriovenous ligation was conducted to better master and apply this model for drug research. Male SD rats of 2-3 months old were employed in this study.The left kidney was removed,and the right kidney received ligation for 40 min and reperfusion for 24 h. Serum creatinine(Crea),urea nitrogen(BUN) and the renal tissue sections were assayed as the basic indicators to evaluate their renal function. The mRNA expression of inflammatory necrosis factors and apoptotic factors was used to evaluate the mechanism of molecular pathophysiological changes. The results showed that the serum Crea and BUN caused by ligation of both renal arteries and veins were significantly higher than those of rats with renal artery ligation. After renal arteriovenous ligation for 40 min and reperfusion for 24 h in rats,the serum Crea of the rats varied from less than 100 μmol·L-1 to more than 430 μmol·L-1. Among them,5 rats showed less than 100 μmol·L-1 serum Crea,20 rats with 100-200 μmol·L-1 serum Crea and 12 rats with more than 430 μmol·L-1. Rats with serum Crea between 300-430 μmol·L-1 accounted for 66.3%(122/184) of the total number of the experiment rats. After 72 h reperfusion,serum Crea in the group of Crea 370-430 μmol·L-1 continued to increase,while the serum Crea in the group of Crea 200-300 μmol·L-1 and the group of Crea 300-370 μmol·L-1 recovered quickly. No matter serum Crea was elevated or decreased,the renal tubules showed pathological changes such as vacuolar degeneration or even necrosis. The mRNA expression levels of Toll-like receptor(TLR4),tumor necrosis factor(TNF-α) and interleukin(IL-6) in renal tissueswere significantly up-regulated,and the effect was most obvious in the group of serum Crea 370-430 μmol·L-1. The study indicated that the model for AKI caused by renal arteriovenous ligation and reperfusion is easy to operate,and the serum Crea and BUN have the characteristics of continuous increase,beneficial to the observation of drug effects. This acute kidney injury is mainly related to the pathophysiological response of inflammatory necrosis.