ABSTRACT
Objective To evaluate the effect and mechanism of nicotinamide mononucleotide (NMN) on ischemia-reperfusion injury (IRI) induced by donor liver after cardiac death in rat models. Methods Rat models of orthotopic liver transplantation were established by "magnetic ring + double cuff" method. SD rats were randomly divided into the sham operation group (Sham group), orthotopic liver transplantation group (OLT group), NMN treatment + orthotopic liver transplantation group (NMN group), NMN+sirtuin-3 (Sirt3) inhibitor (3-TYP) + orthotopic liver transplantation group (NMN+3-TYP group), respectively. Pathological changes and hepatocyte apoptosis of the rats were observed in each group. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were determined. Superoxide dismutase (SOD) and malondialdehyde (MDA) contents in liver tissues were detected. The expression levels of Sirt3, microtubule-associated protein 1 light chain 3 (LC3)Ⅱ, PTEN-induced putative kinase 1 (PINK1), Parkin and translocase of the outer mitochondrial membrane 20 (TOMM20) in liver tissues were measured. Postoperative survival of the rats in each group was analyzed. Results Compared with the Sham group, serum ALT and AST levels were higher in the OLT group. Compared with the OLT group, the levels of ALT and AST were decreased in the NMN group. Compared with the NMN group, the levels of ALT and AST were increased in the NMN +3-TYP group (all P < 0.05). The liver tissue structure of rats in the Sham group was basically normal. In the OLT group, pathological changes, such as evident congestion, vacuolar degeneration and hepatocyte necrosis, were observed in the liver tissues. Compared with the Sham group, Suzuki score and apoptosis rate were higher in the OLT group. Suzuki score and apoptosis rate in the NMN group were lower than those in the OLT group. Suzuki score and apoptosis rate in the NMN+3-TYP group were higher compared with those in the NMN group (all P < 0.05). Compared with the Sham group, the SOD content was decreased, whereas the MDA content was increased in the OLT group. Compared with the OLT group, the SOD content was increased, whereas the MDA content was decreased in the NMN group. Compared with the NMN group, the SOD content was decreased, whereas the MDA content was increased in the NMN+3-TYP group (all P < 0.05). Compared with the Sham group, the relative expression levels of Sirt3 and TOMM20 proteins were down-regulated, whereas those of PINK1, Parkin and LC3Ⅱproteins were up-regulated in the OLT group. Compared with the OLT group, the relative expression levels of Sirt3, PINK1, Parkin and LC3Ⅱproteins were up-regulated, whereas that of TOMM20 protein was down-regulated in the NMN group. Compared with the NMN group, the relative expression levels of PINK1, Parkin and LC3Ⅱproteins were down-regulated, whereas that of TOMM20 protein was up-regulated in the NMN+3-TYP group (all P < 0.05). In the Sham group, the 7 d survival rate of rats was 100%, 50% in the OLT group, 75% in the NMN group and 58% in the NMN+3-TYP group, respectively. Conclusions NMN may enhance the antioxidative capacity of the liver, induce PINK1/Parkin-mediated mitochondrial autophagy, and alleviate IRI of the liver by up-regulating Sirt3, thereby playing a protective role in the donor liver after cardiac death.
ABSTRACT
Objective: To observe the effect of phlegm and blood stasis on the expressions of sirtuin 3(SIRT3)protein and urate transporter 1(URAT1) mRNA in skeletal muscle of diabetic rats with gout. Method: The 40 healthy rats, excepting the normal group, the remaining groups were fed with high-fat diet combined with low-dose streptozotocin solution (40 mg·kg-1) once a day, with blood glucose "16.7 mmol·L-1" as the criterion for the diabetes model. After 4 days, the 5% sodium urate solution was injected into the joint cavity once to induce the gout model. After the successful modeling, the Biling group (10 g·kg-1), the indomethacin group (5 mg·kg-1) and the pioglitazone group (10 mg·kg-1) continued to be administered for 21 days. The normal group and the model group were given the same amount of normal saline. The expression of SIRT3 protein in skeletal muscle tissue was determined by Western blot, URAT1 mRNA expression in bone tissue was detected by quantitative real-time fluorescence polymerase chain reaction(Real-time PCR),and blood was collected to measure blood glucose (GLU), blood uric acid (UA) and C-reactive protein (CRP). Result: Compared with the normal group, GLU, UA and CRP in the model group were significantly increased (PPPPPPPPConclusion: Biling Qutong prescription with effects in purging turbidity, detoxifying and dredging collaterals can significantly reduce the content of serum inflammatory factor CRP, significantly increase the protein expression of SIRT3 in skeletal muscle tissue of model rats, lower the content of URAT1 mRNA, reduce the blood glucose and blood uric acid levels in diabetic gout rats, and protect joints.