Fenofibrate Pre-treatment Suppressed Inflammation by Activating Phosphoinositide 3 Kinase/Protein Kinase B(PI3K/Akt) Signaling in Renal Ischemia-Reperfusion Injury

The aim of this study was to investigate the possible beneficial effects of Fenofibrate on renal ischemia-reperfusion injury（IRI） in mice and its potential mechanism. IRI was induced by bilateral renal ischemia for 60 min followed by reperfusion for 24 h. Eighteen male C57BL/6 mice were randomly divided into three groups： sham-operated group（sham）, IRI＋saline group（IRI group）, IRI＋Fenofibrate（FEN） group. Normal saline or Fenofibrate（3 mg/kg） was intravenously injected 60 min before renal ischemia in IRI group and FEN group, respectively. Blood samples and renal tissues were collected at the end of reperfusion. The renal function, histopathologic changes, and the expression levels of pro-inflammatory cytokines [interleukin-8（IL-8）, tumor necrosis factor alpha（TNF-α） and IL-6] in serum and renal tissue homogenate were assessed. Moreover, the effects of Fenofibrate on activating phosphoinositide 3 kinase/protein kinase B（PI3K/Akt） signaling and peroxisome proliferator-activated receptor-α（PPAR-α） were also measured in renal IRI. The results showed that plasma levels of blood urea nitrogen and creatinine, histopathologic scores and the expression levels of TNF-α, IL-8 and IL-6 were significantly lower in FEN group than in IRI group. Moreover, Fenofibrate pretreatment could further induce PI3K/Akt signal pathway and PPAR-α activation following renal IRI. These findings indicated PPAR-α activation by Fenofibrate exerts protective effects on renal IRI in mice by suppressing inflammation via PI3K/Akt activation. Thus, Fenofibrate could be a novel therapeutic alternative in renal IRI.

Effect and mechanism of adrenomedullin on apoptosis of renal tubular epithelial cell in rats induced by renal ischemia reperfusion injury

Objective To investigate the effect and mechanism of adrenomedullin ( AM ) on apoptosis of renal tubular epithelial cell in rats induced by renal ischemia reperfusion injury. Methods Thirty-two Wistar rats were randomly divided into 4 groups: control group,IRI group, empty plasmid group and AM group. One week after re-

Effects of Compound Shenhua Tablet(复方肾华片) on Renal Tubular Na^+-K^+-ATPase in Rats with Acute Ischemic Reperfusion Injury

Objective： To observe the effect of Compound Shenhua Tablet （复方肾华片, SHT） on the sodium- potassium-exchanging adenosinetriphosphatase （Na＋-K＋-ATPase） in the renal tubular epithelial cells of rats with acute ischemic reperfusion and to investigate the mechanisms underlying the effects of SHT on renal ischemic reperfusion injury （RIRI）. Methods： Fifty male Wistar rats were randomly divided into the sham surgery group, model group, astragaloside group [150 mg/（kg.d）], SHT low-dose group [1.5 g/（kg,d）] and SHT high-dose group [3.0 g/（kg.d）], with 10 rats in each group. After 1 week of continuous intragastric drug administration, surgery was performed to establish the model. At either 24 or 72 h after the surgery, 5 rats in each group were sacrificed, blood biochemistry, renal pathology, immunoblot and immunohistochemical examinations were performed, and double immunofluorescence staining was observed under a laser confocal microscope. Results： Compared with the sham surgery group, the serum creatinine （SCr） and blood urea nitrogen （BUN） levels were significantly increased, Na＋-K＋-ATPase protein level was decreased, and kidney injury molecule-1 （KIM-1） protein level was increased in the model group after the surgery （P〈0.01 or P〈0.05）. Compared with the model group, the SCr, BUN, pathological scores, Na＋-K＋-ATPase, and the KIM-1 protein level of the three treatment groups were significantly improved at 72 h after the surgery （P〈0.05 or P〈0.01）. And the SCr, BUN of the SHT low- and high-dose groups, and the pathological scores of the SHT high-dose group were significantly lower than those of the astragaloside group （P〈0.05）. The Iocalizations of Na＋-K＋-ATPase and megalin of the model group were disrupted, with the distribution areas overlapping with each other and alternately arranged. The severity of the disruption was slightly milder in three treatment groups compared with that of the model group. The results of immunofluorescence staining showed that the SHT high-dose group had a superior effect as compared with the astragaloside group and the SHT low-dose group. Conclusions： The SHT effectively alleviated RIRI caused by ischemic reperfusion, promoted the recovery of the polarity of renal tubular epithelial cells, and protected the renal tubules. The therapeutic effects of SHT were superior to those of astragaloside as a single agent.