Regulation of Nrf2 Pathway by Traditional Chinese Medicine in Prevention and Treatment of Alzheimer's Disease： A Review / 中国实验方剂学杂志

Alzheimer's disease （AD） is a neurodegenerative disease characterized by a progressive decline in memory and cognitive function. β-amyloid protein （Aβ） aggregation and excessive phosphorylation of Tau protein in the brain can increase oxidative stress levels， leading to energy metabolism imbalance， extensive apoptosis of nerve cells， and damage to synaptic function. The nuclear factor E2 related factor 2 （Nrf2） encoded by the Nfe212 gene is known as the "main regulatory factor" of antioxidant response. On the one hand， It can activate antioxidant response elements， such as heme oxygenase-1 （HO-1） and NAD（P）H quinone oxidoreductase1 （NQO1）， increase the expression of antioxidant enzymes glutathione S-transfer （GST） and superoxide dismutase 1 （SOD1）， and reduce the release of reactive oxygen species. On the other hand， it can inhibit immune inflammation， cell apoptosis， and activation of autophagy pathways and delay the progression of AD. Therefore， this article summarized， analyzed， and reviewed the relevant research on the regulation of the Nrf2 signaling pathway by traditional Chinese medicine in the prevention and treatment of AD in the past five years， including its structural characteristics， pathway conduction， mechanism of action in AD， and drug regulation. The results showed that among all reports， research on traditional Chinese medicine compounds occupied a high proportion and mostly focused on flavonoids， with the Nrf2/HO-1 and PI3K/Nrf2 signaling pathways being the most extensively studied. The mechanisms of action were mainly to inhibit oxidative stress， neuroinflammation， and cell apoptosis and improve synaptic function. This indicates that traditional Chinese medicine can regulate multiple Nrf2 signaling pathways and play a role in preventing and treating Alzheimer's disease from multiple mechanisms.

Activation of Nrf2/HO-1/NQO1 Signaling Pathway by Shenqi Tangluo Pill Improves Oxidative Stress Injury of Skeletal Muscle of Type 2 Diabetes Mellitus Mice / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of Shenqi Tangluo pill （SQTLP） on oxidative stress injury of skeletal muscle of type 2 diabetes mellitus （T2DM） mice based on nuclear factor erythroid 2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1）/NAD（P）H quinone oxidoreductase 1 （NQO1） pathway. MethodA total of 60 7-week-old male db/db mice ［specific pathogen-free （SPF） grade］ were selected and fed for one week for adaption. They were divided into the model control group， SQTLP low-， medium- and high-dose （19， 38， and 76 g·kg-1） groups and metformin group （0.26 g·kg-1） by gavage. Each group consisted of 12 mice. Twelve male db/m mice of the same age were selected as the blank group. The intervention was implemented continuously for 8 weeks. Fasting blood glucose （FBG） was detected. Fasting serum insulin （FINS） levels were detected by enzyme-linked immunosorbent assay （ELISA）， and the homeostasis model assessment-insulin resistance （HOMA-IR） index and the homeostasis model assessment-insulin sensitivity index （HOMA-ISI） were calculated. Oral glucose tolerance test （OGTT） and insulin tolerance test （ITT） were conducted. The activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-Px） and the contents of malondialdehyde （MDA） and reduced nicotinamide adenine dinucleotide phosphate （NADPH） in skeletal muscle tissues were detected by biochemical kits. Hematoxylin-eosin （HE） staining was used to observe the pathological changes in skeletal muscle tissues. The levels of reactive oxygen species （ROS） and 4-hydroxynonenal （4-HNE） in skeletal muscle tissue were detected by immunofluorescence （IF）. The expression levels of Nrf2， HO-1， NQO1 and glutamate-cysteine ligase catalytic subunit （GCLC） proteins in skeletal muscle tissues were detected by Western blot. ResultCompared with those in the blank group， FBG， FINS and HOMA-IR in the model group were significantly increased （P<0.05）， while HOMA-ISI was decreased （P<0.05）. The results of OGTT and ITT showed that blood glucose was significantly increased at all time points （P<0.05）， and glucose tolerance and insulin tolerance were significantly impaired. SOD and GSH-Px activities in skeletal muscle tissues were significantly decreased （P<0.05）， and MDA and NADPH contents were significantly increased （P<0.05）. In skeletal muscle tissues， the arrangement of muscle fibers was loose， the nucleus was disordered， and inflammatory cells were infiltrated. The expression levels of ROS and 4-HNE in skeletal muscle tissues were significantly increased （P<0.05）. The protein expression levels of Nrf2， HO-1， NQO1 and GCLC in skeletal muscle tissues were significantly decreased （P<0.05）. Compared with those in the model group， FBG， FINS and HOMA-IR in the metformin group were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that blood glucose in the metformin group was significantly decreased at all time points （P<0.05）. The activities of SOD and GSH-Px in skeletal muscle tissues were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. No obvious abnormality was found in the skeletal muscle tissue of the metformin group. The expressions of ROS and 4-HNE in skeletal muscle tissues were decreased （P<0.05）. The protein expression levels of Nrf2， HO-1， NQO1 and GCLC in skeletal muscle tissues were significantly increased （P<0.05）. Compared with those in the model group， FBG， FINS and HOMA-IR in the SQTLP medium- and high-dose groups were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that the glucose tolerance and insulin tolerance of mice were improved in each dose group of SQTLP. The GSH-Px activity in the SQTLP low-dose group was significantly increased （P<0.05）， and the NADPH content was decreased （P<0.05）. The activities of SOD and GSH-Px in the SQTLP medium- and high-dose groups were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. The skeletal muscle tissue injury of mice in each dose group of SQTLP was ameliorated to different degrees. In the SQTLP medium- and high-dose groups， the expressions of ROS and 4-HNE were decreased （P<0.05）， and the protein expression levels of Nrf2， HO-1， NQO1 and GCLC were significantly increased （P<0.05）. Compared with those in the SQTLP low-dose group， FBG and HOMA-IR in the SQTLP high-dose group were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that the SQTLP high-dose group significantly improved the glucose tolerance and insulin tolerance of mice. The activities of SOD and GSH-Px in skeletal muscle tissues were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. No obvious abnormality was found in the skeletal muscle tissue， the expressions of ROS and 4-HNE were decreased （P<0.05）， and the protein expression levels of Nrf2， HO-1， NQO1 and GCLC were significantly increased （P<0.05） in the skeletal muscle tissue of the SQTLP high-dose group. ConclusionSQTLP can significantly improve IR in T2DM mice， and the mechanism is related to SQTLP activating the Nrf2/HO-1/NQO1 signaling pathway， promoting the expression of antioxidant enzymes， and thus improving the oxidative stress injury in the skeletal muscle.

Xinjia Congrong Tusizi Decoction Regulates Ferroptosis of Granulosa Cells in Rat Model of Premature Ovarian Insufficiency via p53/Nrf2 Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the effects of Xinjia Congrong Tusizi decoction （XJCTD） on ovarian functions in the rat model of premature ovarian insufficiency （POI） and decipher the mechanism of regulating the tumor suppressor protein （p53）/nuclear factor E2-related factor 2 （Nrf2） pathway to attenuate granulosa cell ferroptosis. MethodForty-eight SPF-grade female SD rats were randomized into control， model， low-， medium-， and high-dose （1.1， 2.2， 4.4 g·kg-1） XJCTD， and Western medicine （coenzyme Q10， 0.002 7 g·kg-1） groups， with eight rats in each group. The rat model of POI was established by gavage of triptolide （TP）， and after successful modeling， each group was administrated with the corresponding drugs by gavage for 14 d. The body weight and ovarian weight of each rat were weighed and the ovarian index was calculated. The morphology of the ovarian tissue was observed by hematoxylin-eosin staining， and the proportions of growing follicles and atretic follicles were calculated. The serum levels of anti-Müllerian hormone （AMM）， estradiol （E2）， and follicle-stimulating hormone （FSH） were measured by enzyme-linked immunosorbent assay （ELISA）. The DCFH-DA fluorescent probe was used to measure the reactive oxygen species （ROS） content in granulosa cells. The content of cellular Ferrous ion （Fe2+）， lipid peroxide （LPO）， malondialdehyde （MDA）， glutathione （GSH）， and superoxide dismutase （SOD） was detected by colorimetry. The expression of the tumor suppressor protein p53，Nrf2， solute carrier family 7 member 11 （SLC7A11）， and glutathione peroxidase 4 （GPX4） was determined by immunohistochemistry and Western blot. ResultCompared with the control group， the model group showed decreased ovarian weight， body weight， and ovarian index （P<0.01）， reduced ovarian tissue volume and proportion of growing follicles （P<0.01）， increased proportion of atretic follicles （P<0.01）， lowered AMH and E2 levels and elevated FSH level in the serum （P<0.01）， and elevated levels of Fe2+， ROS， LPO， and MDA （P<0.01） and lowered levels of GSH and SOD in granulosa cells （P<0.01）. Moreover， the modeling up-regulated the expression of p53 （P<0.01） and down-regulated the expression of Nrf2， SLC7A11， and GPX4 （P<0.05， P<0.01） in the ovarian tissue. Compared with the model group， XJCTD increased the body weight， ovarian weight， and ovarian index （P<0.01）， alleviated the pathological changes in the ovarian tissue， increased the proportion of growing follicles （P<0.01）， decreased the proportion of atretic follicles （P<0.01）， and reduced the content of ROS in granulosa cells （P<0.05， P<0.01）. In addition， medium- and high-dose XJCTD lowered the FSH level （P<0.01） and raised E2 and AMH levels （P<0.01） in the serum， reduced the Fe2+ content （P<0.05， P<0.01）， and increased the SOD content （P<0.01） in granulosa cells. High-dose XJCTD reduced the LPO and MDA content （P<0.01） and increased the SOD content （P<0.01） in the granulosa cells， down-regulated the expression of p53 （P<0.05）， and up-regulated the expression of Nrf2， SLC7A11， and GPX4 in the ovarian tissue （P<0.05， P<0.01）. ConclusionXJCTD may protect the ovarian function in the rat model of POI by regulating the p53/Nrf2 signaling pathway to attenuate the ferroptosis of ovarian granulosa cells.

Mechanism on Banxia Xiexintang Inducing Ferroptosis in Gastric Cancer Cells Based on Nrf2/GPX4 Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo observe the effect of Banxia Xiexintang （BXT） on the proliferation of human gastric cancer HGC-27， MKN-45， and AGS cells and its mechanism. MethodCell counting kit-8 （CCK-8） was used to detect the effects of different concentrations of BXT-containing serum （5%， 10%， and 20%） on the proliferation of HGC-27， MKN-45， and AGS cells. A mitochondrial membrane potential probe （TMRE） was used to detect the expression of mitochondrial membrane potential in cells. A kit was used to detect iron ion （Fe2+） content， lipid peroxide （LPO）， and superoxide dismutase （SOD） activity. Western blot was used to detect the protein expression levels of glycogen synthase3β （GSK3β）， phosphorylated GSK3β （p-GSK3β）， nuclear factor E2 related factor 2 （Nrf2）， and glutathione peroxidase 4 （GPX4）. The real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of member 11 of the cystine/glutamic acid reverse transporter solute vector family 7 （SLC7A11）， member 2 of the heavy chain solute vector family 3 （SLC3A2）， transferrin receptor 3 （TFRC）， and tumor protein （TP）53. ResultCCK-8 results showed that BXT and capecitabine could significantly reduce the survival rate of three kinds of gastric cancer cells after treatment with drug-containing serum for 24 h （P<0.01）. After 48 h of intervention with drug-containing serum， the survival rate of three kinds of gastric cancer cells was significantly decreased in both the capecitabine group and the BXT group compared with the blank group. The BXT group was dose-dependent， with 20% BXT having the most significant effect （P<0.01）. In terms of biochemical indicators of ferroptosis， compared with the blank group， BXT and capecitabine significantly decreased the expression of mitochondrial membrane potential （P<0.01） and SOD activity （P<0.01） and significantly increased the contents of LPO and Fe2+ （P<0.01）， so as to improve the sensitivity of gastric cancer cells to ferroptosis. In terms of the Nrf2/GPX4 pathway， compared with the blank group， the BXT group could reduce the protein expressions of p-GSK3β， Nrf2， and GPX4 （P<0.01） in gastric cancer cells and increase mRNA expressions of SLC7A11 and SLC3A2 （P<0.05）. It could also increase the protein expression of GSK3β （P<0.01） and mRNA expression of TP53 and TFRC （P<0.05， P<0.01） in gastric cancer cells. Inhibition of the Nrf2/GPX4 pathway induces ferroptosis in gastric cancer cells. Compared with the capecitabine group， the 20% BXT group showed a more obvious effect. ConclusionBanxia Xiexintang can induce ferroptosis in gastric cancer cells HGC-27， MKN-45， and AGS by inhibiting the Nrf2/GPX4 pathway.

Buzhong Yiqitang Regulates Apoptosis via Nrf2/ROS Pathway to Alleviate Cisplatin Resistance in A549/DDP Cells / 中国实验方剂学杂志

ObjectiveTo explore the mechanism of Buzhong Yiqitang-containing serum in alleviating the cisplatin resistance in human non-small cell lung cancer （A549/DDP） cells via regulating the nuclear factor E2-related factor 2 （Nrf2）/reactive oxygen species （ROS） signaling pathway. MethodThe serum containing Buzhong Yiqitang was prepared and A549/DDP cells were cultured and randomly grouped： blank （10% blank serum）， cisplatin （10% blank serum+20 mg·L-1 cisplatin）， Buzhong Yiqitang （10% Buzhong Yiqitang-containing serum+20 mg·L-1 cisplatin）， ML385 （10% blank serum+5 μmol·L-1 ML385+20 mg·L-1 cisplatin）， Buzhong Yiqitang+ML385 （10% Buzhong Yiqitang-containing serum+5 μmol·L-1 ML385+20 mg·L-1 cisplatin）， tertiary butylhydroquinone （TBHQ） （10% blank serum+5 μmol·L-1 TBHQ+20 mg·L-1 cisplatin）， and Buzhong Yiqitang+TBHQ （10% Buzhong Yiqitang-containing serum+5 μmol·L-1 TBHQ+20 mg·L-1 cisplatin）. The median inhibitory concentration （IC50） of cisplatin in each group was determined by the cell counting kit-8 （CCK-8） method and the resistance index （RI） was calculated. The apoptosis rate was detected by flow cytometry. The ROS content of each group was determined with the DCFH-DA fluorescence probe. Western blot was employed to determine the protein levels of Nrf2， cleaved cysteinyl aspartate-specific protease-3 （cleaved Caspase-3）， cytochrome C （Cyt C）， and B-cell lymphoma-2 （Bcl-2）. ResultCompared with those in the cisplatin group， the IC50 and RI of A549/DDP cells to cisplatin in Buzhong Yiqitang， ML385， and Buzhong Yiqitang+ML385 groups decreased （P˂0.05）. Compared with the blank group， the cisplatin， Buzhong Yiqitang， ML385， and Buzhong Yiqitang+ML385 groups showed increased apoptosis rate of A549/DDP cells （P˂0.05）. Compared with the blank group， cisplatin promoted the expression of Nrf2 （P˂0.05）. Compared with the cisplatin group， Buzhong Yiqitang， ML385， and Buzhong Yiqitang+ML385 inhibited the expression of Nrf2 （P<0.05）， elevated the ROS level （P˂0.05）， up-regulated the protein levels of cleaved Caspase-3 and Cyt C， and down-regulated the protein level of Bcl-2 （P<0.05）， which were the most significant in the Buzhong Yiqitang+ML385 group. Compared with the cisplatin group， the TBHQ group showed increased IC50 and RI of cisplatin （P<0.05）， decreased apoptosis rate of A549/DDP cells （P<0.05）， up-regulated protein levels of Nrf2 and Bcl-2 （P<0.05）， lowered level of ROS （P˂0.05）， and down-regulated protein levels of cleaved Caspase-3 and Cyt C （P<0.05）. Compared with the TBHQ group， Buzhong Yiqitang+TBHQ decreased the IC50 and RI of cisplatin in A549/DDP cells （P<0.05）， increased the apoptosis rate （P<0.05）， down-regulated the protein levels of Nrf2 and Bcl-2 （P<0.05）， increased ROS （P˂0.05）， and up-regulated the protein levels of cleaved Caspase-3 and Cyt C （P<0.05）. ConclusionBuzhong Yiqitang induced apoptosis by inhibiting Nrf2/ROS pathway to alleviate cisplatin resistance in A549/DDP cells.

Role of Oxidative Stress in Ulcerative Colitis and Traditional Chinese Medicine Prevention and Treatment： A Review / 中国实验方剂学杂志

Ulcerative colitis （UC） is a commonly seen digestive system disease with unclear pathogenesis. The condition is complex and variable， often chronic， and has a long treatment period with no specific cure. Currently， the treatment of UC often involves the use of corticosteroids， aminosalicylates， and biologics in western medicine， which provide fast-acting and definite efficacy in the short term. However， with prolonged medication， some patients may develop drug resistance and worsening of the disease， leading to the occurrence of colon cancer. Research has found that oxidative stress is one of the important pathogenic factors in UC and influences its onset and development. Oxidative stress is a state of imbalance between oxidative products and the antioxidant system in the body， characterized by overexpression of oxidative products such as malondialdehyde （MDA）， reactive oxygen species （ROS）， nitric oxide （NO）， or deficiency of antioxidant enzymes such as superoxide dismutase （SOD）， catalase （CAT）， and glutathione （GSH）. It is worth noting that traditional Chinese medicine （TCM）， as a unique characteristic medicine of China， has achieved significant efficacy in the treatment of UC. Studies have shown that TCM effectively inhibits the occurrence of UC by suppressing the accumulation of metabolites and antagonizes the development of UC by enhancing the antioxidant system. Therefore， using TCM to regulate the oxidative balance as a diagnostic and therapeutic approach may be a new method and direction for the treatment of UC in the future. Based on the above research， this article summarized the mechanisms of key pathogenic proteins in oxidative stress and the occurrence and development of UC， and compiled the effective ingredients of Chinese medicine， single drugs， prescriptions， and acupuncture and moxibustion in regulating upstream and downstream target proteins of oxidative stress. These interventions can reduce pathological damage to the intestinal mucosa， lower the colon injury index， enrich the intestinal microbiota， increase colon length， and improve clinical symptoms of UC. The article is expected to expand the application of TCM in the treatment of UC and provide a reliable scientific theoretical basis.

Role of Nrf2/HO-1 Signaling Pathway in Myocardial Infarction and Traditional Chinese Medicine Intervention： A Review / 中国实验方剂学杂志

Myocardial infarction （MI） is a common cardiovascular disease in clinical practice and one of the main causes of cardiovascular mortality. Its pathogenesis is complex and associated with oxidative stress reactions. Nuclear factor E2-related factor 2 （Nrf2） is a key factor in regulating oxidative stress reactions. It can regulate the expression of heme oxygenase-1 （HO-1）， playing a role in maintaining the oxidative-reductive homeostasis in the body. During the course of MI， the biological activity and levels of Nrf2 and HO-1 decrease， leading to weakened tissue antioxidant and anti-inflammatory capabilities， endothelial damage in myocardial blood vessels， release of vascular cell adhesion factors， and impaired endothelial function. In recent years， many basic research studies have explored the role and mechanisms of traditional Chinese medicine （TCM） in treating MI by modulating the Nrf2/HO-1 signaling pathway. The results have indicated that the Nrf2/HO-1 signaling pathway is an important potential target for TCM in the treatment of MI. This article reviewed the mechanism of the Nrf2/HO-1 signaling pathway in MI and the research progress of TCM in targeting and regulating this pathway， aiming to provide a theoretical basis for the prevention and treatment of MI and further drug development.

Engineered Bacillus subtilis alleviates intestinal oxidative injury through Nrf2-Keap1 pathway in enterotoxigenic Escherichia coli (ETEC) K88-infected piglet / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Engineered probiotics can serve as therapeutics based on their ability of produce recombinant immune-stimulating properties. In this study, we built the recombinant Bacillus subtilis WB800 expressing antimicrobial peptide KR32 (WB800-KR32) using genetic engineering methods and investigated its protective effects of nuclear factor-E2-related factor 2 (Nrf2)‍-Kelch-like ECH-associated protein 1 (Keap1) pathway activation in intestinal oxidative disturbance induced by enterotoxigenic Escherichia coli (ETEC) K88 in weaned piglets. Twenty-eight weaned piglets were randomly distributed into four treatment groups with seven replicates fed with a basal diet. The feed of the control group (CON) was infused with normal sterilized saline; meanwhile, the ETEC, ETEC+WB800, and ETEC+WB800-KR32 groups were orally administered normal sterilized saline, 5×1010 CFU (CFU: colony forming units) WB800, and 5×1010 CFU WB800-KR32, respectively, on Days 1‍‒‍14 and all infused with ETEC K88 1×1010 CFU on Days 15‍‒‍17. The results showed that pretreatment with WB800-KR32 attenuated ETEC-induced intestinal disturbance, improved the mucosal activity of antioxidant enzyme (catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx)) and decreased the content of malondialdehyde (MDA). More importantly, WB800-KR32 downregulated genes involved in antioxidant defense (GPx and SOD1). Interestingly, WB800-KR32 upregulated the protein expression of Nrf2 and downregulated the protein expression of Keap1 in the ileum. WB800-KR32 markedly changed the richness estimators (Ace and Chao) of gut microbiota and increased the abundance of Eubacterium_rectale_ATCC_33656 in the feces. The results suggested that WB800-KR32 may alleviate ETEC-induced intestinal oxidative injury through the Nrf2-Keap1 pathway, providing a new perspective for WB800-KR32 as potential therapeutics to regulate intestinal oxidative disturbance in ETEC K88 infection.

Neuroprotection of Natural Products Based on Keap1/Nrf2/ARE Signaling Pathway： A Review / 中国实验方剂学杂志

The pathological manifestations of neurodegenerative diseases， such as Alzheimer's disease， Parkinson's disease， and multiple sclerosis， are abnormal protein aggregation and accumulation， microglia activation， and mitochondrial dysfunction， which eventually lead to the gradual loss of neuronal structure or function and deteriorate over time. These pathological processes are related to the production of reactive oxygen species （ROS）， which can cause oxidative stress and damage proteins， lipids， and DNA， leading to cell and tissue injuries. The Kelch-like ECH-associated protein 1 （Keap1）/nuclear factor E2-related factor 2 （Nrf2）/antioxidant response element （ARE） signaling pathway is the main mechanism to maintain the redox balance of the body and defend against oxidative stress injury. Nrf2 activates the expression of a series of antioxidant genes related to ARE through the dissociation of Keap1 and nuclear transfer in the cytoplasm to protect the body from oxidative damage. Therefore， the discovery and study of the Keap1/Nrf2/ARE signaling pathway activator is of great significance for the prevention and treatment of neurodegenerative diseases. Because of the remarkable biological activity and slight side effects， natural products are a treasure trove for new drug research and development. Studies have shown that a variety of natural products can activate the Keap1/Nrf2/ARE signaling pathway and play a neuroprotective role. According to the structural characteristics， natural products can be divided into flavonoids， terpenoids， volatile oils， polyphenols， and phenylpropanoids. This study summarized the underlying mechanism of the Keap1/Nrf2/ARE signaling pathway in regulating diseases and reviewed the research progress on natural products based on this signaling pathway in neuroprotection to provide references for the development of clinical drugs for the prevention and treatment of neurodegenerative diseases.

Anti-oxidative Stress Effect and Mechanism of Huangqintang on Caco-2 Cells Through Nrf2 Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo verify the anti-oxidative stress effect of Huangqintang based on the nuclear factor E2-related factor 2 （Nrf2） signaling pathway by using Caco-2 cells as a carrier and RNA interference （RNAi） technology with in vitro experiments. MethodThe Caco-2 cells in the logarithmic growth phase were transfected with siRNA to construct siRNA Caco-2 cells. After normal Caco-2 cells and siRNA Caco-2 cells were incubated with Huangqintang of different doses， RNA and protein were extracted. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot were used to detect the mRNA and protein expression of heme oxygenase-1 （HO-1）， NAD（P）H quinone oxidoreductase 1 （NQO1）， glutathione S-transferase （GST）， Kelch-like ECH-associated protein 1 （Keap1）， and Nrf2. Meanwhile， the activities of superoxide dismutase （SOD） and GSH-Px， as well as the expression levels of malondialdehyde （MDA） and reactive oxygen species （ROS）， were detected by the colorimetric method and the probe method. ResultCompared with the results in the normal group， only the 400 mg·L-1 Huangqintang group and the sulforaphane （SFN） group could reduce the content of ROS and MDA in Caco-2 cells （P<0.01）， while the activities of SOD and GSH-Px in the cells of the Huangqintang groups and the SFN group showed an upward trend. Furthermore， there were significant differences in the 400 mg·L-1 Huangqintang group/the SFN group and the normal group （P<0.01）. Meanwhile， the protein and mRNA expression levels of HO-1， GST， Keap1， NQO1， and Nrf2 showed an upward trend in all groups （P<0.05， P<0.01）. After transfection， compared with the normal group， the model group showed increased content of MDA and ROS， blunted activities of GSH-Px and SOD， and reduced protein and mRNA expression of HO-1， GST， Keap1， and NQO1 （P<0.05， P<0.01）. After drug incubation， compared with the model group， the SFN group showed potentiated SOD activity， and the SFN group and the Huangqintang groups showed enhanced GSH-Px activity （P<0.01）. Moreover， the activities of SOD and GSH-Px in the 400 and 200 mg·L-1 Huangqintang groups and the SFN group showed an upward trend （P<0.01）， and the content of MDA in the 400 mg·L-1 Huangqintang group and the SFN group showed a downward trend. ROS decreased in all groups with drug intervention （P<0.01）， and the protein and mRNA expression of HO-1， GST， Keap1， NQO1， and Nrf2 increased to varying degrees （P<0.05， P<0.01）. ConclusionHuangqintang can play an anti-oxidative stress role by regulating the Nrf2 pathway.

Shenling Baizhusan Improves Spermatogenesis in Hyperuricemia Oligoasthenospermia Mice by Regulating Nrf2/ARE Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of Shenling Baizhusan on the treatment of oligoasthenospermia with hyperuricemia （HUA）. MethodThirty-two male Kunming （KM） mice were randomly divided into blank group （n=6）， model group （n=6）， high-dose Shenling Baizhusan group （n=7）， low-dose Shenling Baizhusan group （n=7）， and febuxostat group （n=6）. Except for the blank group， all other groups received intraperitoneal injection of potassium oxazinate suspension （600 mg·kg-1） for 7 days. After modeling， the high-dose Shenling Baizhusan group and the low-dose Shenling Baizhusan group were orally administered with 20.14 g·kg-1 and 10.07 g·kg-1 of Shenling Baizhusan， respectively. The Febuxostat group was orally administered with 0.25 g·kg-1 of Febuxostat， while the blank group and model group were orally administered with the same volume of physiological saline. Oral administration was performed once a day for 14 consecutive days， after which samples were collected. Biochemical methods were used to measure serum uric acid （UA）， superoxide dismutase （SOD） and malondialdehyde （MDA） in testicular tissue. Hematoxylin-eosin （HE） staining was used to observe the histopathological changes in testicular tissue and evaluate the spermatogenesis function. Automated sperm analyzer was used to measure sperm density and motility. Single-cell gel electrophoresis （SCGE） was used to assess sperm DNA integrity. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL） was used to detect testicular cell apoptosis rate. Western blot analysis was performed to measure the protein expression levels of Kelch-like ECH-associated protein 1 （Keap1）， nuclear factor E2-related factor 2 （Nrf2）， heme oxygenase-1 （HO-1）， B-cell lymphoma-2 （Bcl-2）， Bcl-2-associated X protein （Bax）， and Caspase-3 in testicular tissue. Real-time polymerase chain reaction （PCR） was conducted to evaluate the mRNA expression levels of Keap1， Nrf2， and HO-1 in testicular tissue. ResultCompared with the blank group， the model group showed elevated serum UA level （P<0.01）， decreased testicular spermatogenesis function， sperm density， and motility （P<0.01）， and increased sperm trailing rate and testicular cell apoptosis rate （P<0.01）. Compared with the model group， the high-dose Shenling Baizhusan group showed significant improvements in the above-mentioned indicators （P<0.05， P<0.01）. Additionally， the expression levels of Keap1， Bax， and Caspase-3 in testicular tissue were reduced， while the expression levels of Nrf2， HO-1， and Bcl-2 increased （P<0.05， P<0.01）. The mRNA level of Keap1 decreased （P<0.05， P<0.01）， while the mRNA levels of Nrf2 and HO-1 increased （P<0.05， P<0.01）. ConclusionShenling Baizhusan can significantly improve HUA oligoasthenospermia， and its mechanism may be related to the Nrf2/antioxidant response element （ARE） signaling pathway.

Plumbagin Induces Ferroptosis Through Nrf-2/Keap1 Signaling Pathway in Bladder Cancer Cells / 中国实验方剂学杂志

ObjectiveTo explore the mechanism of plumbagin as a novel ferroptosis inducer in bladder cancer inhibition. MethodBladder cancer T24 cells were used in this study. The effect of different concentrations of plumbagin （0.1， 1， 2， 3， 6， 12， 24， 48 μmol·L-1） on the viability of T24 cells was detected by cell counting kit-8 （CCK-8）. The effect of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on the apoptosis of T24 cells was detected by annexin V-fluorescein isothiocyanate （Annexin V FITC）/PI apoptosis kit. Different inhibitors （ferroptosis inhibitor Fer-1， apoptosis inhibitor VAD， and necroptosis inhibitor Nec-1） were used in combination with plumbagin （6 μmol·L-1）. Reactive oxygen species （ROS） fluorescent probe （DCFH-DA）， malonaldehyde （MDA）， and glutathione （GSH） kits were used to detect the effects of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on the level of ROS and the content of MDA and GSH in T24 cells， respectively. The effect of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on peroxide levels in T24 cells was detected by C11-BODIPY fluorescent probe. Western blot was used to detect the effect of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on the protein expression of solute carrier family 7 member 11 （SLC7A11）， glutathione peroxidase 4 （GPX4）， nuclear factor E2-related factor-2 （Nrf-2）， and Kelch-like ECH-associated protein 1 （Keap1）. ResultCompared with the blank group， plumbagin could inhibit the activity of T24 cells （P<0.05） with IC50 of 3.52 μmol·L-1. At the concentrations of 1.5， 3， 6 μmol·L-1， plumbagin significantly promoted the apoptosis of T24 cells （P<0.05） as compared with the blank group. Compared with the plumbagin group at 6 μmol·L-1， the ferroptosis inhibitor and apoptosis inhibitor groups could reverse the inhibitory effect of 6 μmol·L-1 plumbagin on the proliferation of T24 cells （P<0.05）. Compared with the blank group， the plumbagin groups at 1.5， 3， 6 μmol·L-1 showed increased content of ROS， MDA， and lipid peroxides in T24 cells， decreased GSH level， and reduced SLC7A11， GPX4， and Nrf-2/Keap1 （P<0.05）. Conclusionplumbagin can induce ferroptosis， and its mechanism is related to the Nrf-2/Keap1 signaling pathway.

Role of Nrf2/HO-1 Signaling Pathway in Osteoporosis and Chinese Medicine Intervention： A Review / 中国实验方剂学杂志

Osteoporosis is a chronic skeletal disease characterized by low bone mass， destruction of bone tissue microarchitecture， and imbalance of bone homeostasis， leading to increased bone fragility and increased risk of fractures. Oxidative stress caused by the disruption of the balance between excess reactive oxygen species （ROS） and the anti-oxidative system is an important factor in the occurrence and progression of osteoporosis. Nuclear factor E2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1） is an important anti-oxidative stress pathway. Nrf2 is a primary factor in regulating cellular oxidative stress. Activating Nrf2 can stimulate the expression of HO-1. HO-1 is a key enzyme whose metabolites are bile green Oxygen， carbon monoxide， and free iron. The metabolites can scavenge ROS， thereby exerting an antioxidant effect in cells. At present， domestic and foreign scholars have reported that the Nrf2/HO-1 signaling pathway is closely related to the occurrence and development of osteoporosis and the mechanism of drugs. Chinese medicine can effectively solve the insufficiency of western medicine with multi-target， multi-channel， and multi-level advantages. Chinese medicine can resist oxidative stress， inflammatory response， and apoptosis by regulating the Nrf2/HO-1 signaling pathway， thus treating osteoporosis. This article reviewed the relationship between Nrf2/HO-1 signaling pathway and its key target protein factors and osteoporosis， to clarify the important role of the Nrf2/HO-1 signaling pathway in osteoporosis. At the same time， a systematic summary of Chinese medicines targeting and regulating the Nrf2/HO-1 signaling pathway for the treatment of osteoporosis was conducted， to provide a theoretical basis for further precise treatment of osteoporosis.

Protective Effect of Angelicae Sinensis Radix-Chuanxiong Rhizoma Medicated Serum Against H2O2-induced Oxidative Damage of PC12 Cells Based on Nrf2/ARE Signaling Pathway / 中国实验方剂学杂志

Objective:To investigate the protective effect and molecular mechanism of Angelicae Sinensis Radix-Chuanxiong Rhizoma medicated serum （ASRCRS） against oxidative damage of PC12 cells induced by H₂O₂. Method:Oxidative damage of PC12 cells was induced by H₂O₂<italic> in vitro</italic>， and intervention was performed in the low-， medium-， and high-dose ASRCRS groups with a final volume fraction of 15%. The cell viability was determined by methyl thiazolyl tetrazolium （MTT） assay. Cell morphology was observed by an inverted fluorescence microscope. The content of lactate dehydrogenase （LDH） and malondialdehyde （MDA）， the activity of superoxide dismutase （SOD）， and the distribution of reactive oxygen species （ROS） in the cell supernatant were detected by the kits. Cell apoptosis was detected by Annexin V-FITC/PI double staining. The protein expression levels of nuclear factor E₂-related factor 2 （Nrf2）， Kelch-like epichlorohydrin associated protein-1 （Keap1）， heme oxygenase-1 （HO-1）， and SOD1 were detected by Western blot. Result:Oxidative damage was induced by 300 μmol·L^-1 H₂O₂ for 24 hours. Compared with the normal group， the model group showed abnormal cell morphology， reduced cell viability （<italic>P</italic><0.01）， increased LDH and MDA （<italic>P</italic><0.01）， blunted SOD activity， elevated intracellular distribution of ROS， down-regulated protein expression of Nrf2， HO-1， and SOD1 （<italic>P</italic><0.05， <italic>P</italic><0.05）， and up-regulated protein expression of Keap1 （<italic>P</italic><0.01）. Compared with the model group， ASRCRS groups displayed improved cell morphology， increased cell viability， inhibited cell apoptosis， potentiated SOD activity （<italic>P</italic><0.01）， suppressed release of LDH （<italic>P</italic><0.01） and generation of ROS， decreased content of MDA （<italic>P</italic><0.01）， up-regulated protein expression of Nrf2， HO-1 and SOD1 （<italic>P</italic><0.05， <italic>P</italic><0.01）， and down-regulated protein expression of Keap1 （<italic>P</italic><0.01）. Conclusion:ASRCRS could protect PC12 cells from oxidative damage induced by H₂O₂ by up-regulating the expression of Nrf2 to activate the Nrf2/antioxidant response element （ARE） signaling pathway， enhancing the ability to resist oxidative damage， and inhibiting cell apoptosis.

Protective Effect of Xiangsha Yuyang Decoction on Oxidative Injury in Rats with Gastric Ulcer Based on p62/Keap1/Nrf2 Signal Pathway / 中国实验方剂学杂志

Objective:To confirm the protective effect of Xiangsha Yuyang decoction on acetic acid-induced gastric ulcer model rats and explore its mechanism， so as to provide experimental basis for clinical drug use. Method:The 60 SPF Wistar rats were randomly divided into 6 groups： group， model group， high， middle and low dose groups of Xiangsha Yuyang decoction and omeprazole control group. The rat model of gastric ulcer was induced by acetic acid. The rats in the high， middle and low dose groups of Xiangsha Yuyang decoction were intragastrically administered at the dose of 28，14，7 g·kg^-1， and with omeprazole at the dose of 4.17 g·kg^-1in normal saline， respectively. The rats in the blank group and model group were intragastrically infused with the same volume of normal saline once a day. After 14 days of continuous treatment， the rats were killed， the blood was collected， the area and inhibition rate of gastric ulcer were measured and calculated， the histopathological sections of gastric mucosa were made and the state of gastric mucosal injury was observed， and the changes of gastric mucosal repair factor， gastric tissue related protein， oxidative stress factor and inflammatory factor in serum were detected by enzyme-linked immunosorbent assay（ELISA）. Detected the expression of p62 Kelch-like epichlorohydrin-related protein 1 （Keap1）， nuclear transcription factor E2 related factor 2 （Nrf2） and heme oxygenase-1 （HO-1） signal pathway-related proteins in gastric mucosa by Western blot. Result:Compared with control group， the gastric mucosa of the model group showed obvious pathological changes and a large number of leukocytes infiltrated. In model group， the ulcer area was significantly increased（<italic>P</italic><0.01）， the contents of mucin mucoprotein 5AC （MUC5AC）， epidermal growth factor （EGF）， superoxide dismutase （SOD） and increased prostaglandin E₂ （PGE₂） were significantly decreased（<italic>P</italic><0.01）， the gastrin （GAS）， 8-hydroxydeoxyguanosine （8-OHdG）， malondialdehyde （MDA）， tumor necrosis factor-<italic>α</italic> （TNF-<italic>α</italic>）， cyclooxygenase-2 （COX-2） were significantly increased. The expression of HO-1 and Nrf2 protein decreased significantly（<italic>P</italic><0.01）， the content of Keap1 increased significantly （<italic>P</italic><0.05）， and the expression of p62 protein decreased. Compared with model group， the hierarchical structure of cells in Xiangsha Yuyang decoction high dose group and omeprazole group were clearer and regular， middle and low dose groups could also repair gastric mucosa to a certain extent. The high and middle dose groups of Xiangsha Yuyang decoction could significantly reduce the gastric ulcer area of acetic acid-induced gastric ulcer rat model （<italic>P</italic><0.01） and increase the ulcer inhibition rate. It can effectively promote the expression of MUC5AC and EGF in gastric mucosa， decrease the level of GAS（<italic>P</italic><0.05，<italic>P</italic><0.01）， decrease the level of 8-OHdG and MDA， increase the activity of SOD（<italic>P</italic><0.01）， decrease the expression level of TNF-<italic>α</italic> and COX-2， increase the content of PGE₂， and significantly increase the amount of Nrf2 and HO-1 protein in gastric mucosa（<italic>P</italic><0.01）. The high dose group of Xiangsha Yuyang decoction could decrease the protein expression of Keap1（<italic>P</italic><0.05） and increase the expression of p62 protein. Conclusion:Xiangsha Yuyang decoction is effective in the treatment of acetic acid-induced gastric ulcer model rats， which can effectively reduce the ulcer area， increase the ulcer inhibition rate and protect the ulcer tissue. Its mechanism may be related to activating p62/Keap1/Nrf2 signal pathway and regulating the expression of related genes so as to improve inflammatory response and regulate oxidative stress response.

Mild hypothermia alleviates renal ischemia-reperfusion injury by up-regulating the expression of cold-shock protein RBM3 / 器官移植

Objective To evaluate the effect of mild hypothermia on the renal ischemia-reperfusion injury (IRI), and the expression profile of RNA-binding motif protein 3(RBM3) and its downstream effector molecules during this process. Methods Eighteen healthy SD male rats were randomly divided into the normal control (NC) group, IRI group and mild hypothermia pretreat (MHP) group, with 6 rats in each group. Serum creatinine level was measured to evaluate the renal function. Hematoxylin-eosin (HE) staining was performed to assess the renal tissue injury. Western blot was used to determine the relative expression levels of RBM3, Yes-associated protein 1(YAP1), nuclear factor E2-related factor 2(Nrf2), B cell-lymphoma-2(Bcl-2) and Bcl-2-associated X protein (Bax) in the kidney tissues. Immunohistochemical staining was employed to further detect the expression levels of RBM3 and YAP1 proteins. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay was adopted to detect the cell apoptosis of kidney tissues. Malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were evaluated to determine the oxidative stress level of kidney tissues. Results Compared with the NC group, the serum creatinine level, the pathological injury score of kidney tissues and the expression levels of RBM3, YAP1 and Nrf2 proteins were significantly up-regulated, the Bcl-2/Bax ratio was considerably lower, the apoptosis rate was remarkably elevated, the MDA content was significantly increased and the SOD activity was dramatically reduced in the IRI and MHP groups (all P < 0.05). Compared with the IRI group, the serum creatinine level and the pathological injury score of kidney tissues were significantly decreased, the expression levels of RBM3, YAP1 and Nrf2 proteins were significantly up-regulated, the Bcl-2/Bax ratio was considerably higher, the apoptosis rate was significantly decreased, the MDA content was significantly decreased and the SOD activity was considerably elevated in the MHP group (all P < 0.05). Conclusions Mild hypothermia may exert protective effect upon renal IRI and it could alleviate cell apoptosis and oxidative stress injury induced by IRI, probably by up-regulating the expression level of RBM3 and its downstream effector molecules of YAP1 and Nrf2.

Effect of Gastrodiae Rhizoma Powder on Prevention of Dementia and Oxidation Resistance in Mice / 中国实验方剂学杂志

Objective::To study whether long-term administration of Gastrodiae Rhizoma powder can improve the learning and memory ability of APPswe/PSldE9 double transgenic (APP/PS1) Alzheimer' s disease(AD) model mice and delay the progress of AD whether these effects are related to the regulation of antioxidant stress pathway in Kelch-like epoxylopropylamine-related protein 1(Keap1)-nuclear factor E2 related factor 2 (Nrf2)/heme oxygenase(HO)-1, and further explore the neuroprotective mechanism of Gastrodiae Rhizoma powder and its role in the prevention and treatment of AD. Method::APP/PS1 double transgenic mice model, the mice consisted of five groups: normal, normal administration group, model group, Gastrodiae Rhizoma powder prevention group, Gastrodiae Rhizoma powder treatment group.The mice in the normal administration group and the Gastrodiae Rhizoma powder prevention group were given the same dose of Gastrodiae Rhizoma powder (1.5 g·kg-1) daily at the age of 8 weeks.The normal group and model group were given the same amount of normal saline at the same time, until 24 weeks old, Morris water maze was used to test the learning and memory ability of mice, and the treatment group was treated with Gastrodiae Rhizoma powder at 22 weeks old.The mice were given the same dose of Gastrodiae Rhizoma powder (1.5 g·kg-1) every day for 2 weeks.The number of crossing platform, escape latency and platform residence time of mice were detected by Morris water maze from 24 weeks old to 24 weeks old.RNA, Real-time PCR was extracted from mouse hippocampus to detect the mRNA level of Nrf2, HO-1, Keap1, and Western blot was used to detect the expression of Nrf2, HO-1, Keap1 protein in mouse hippocampus. Result::Compared with normal group, the water maze test showed that the learning and memory ability of model group was lower than that of the model group (P<0.01), and the learning and memory ability of Gastrodiae Rhizoma powder prevention group and Gastrodiae Rhizoma powder treatment group was significantly higher than that of model group (P<0.01). Compared with normal group, the levels of Nrf2, HO-1 and protein in the hippocampus in model group decreased in varying degrees (P<0.05). Compared with model group, Gastrodiae Rhizoma powder prevented Nrf2, in the hippocampus of mice in model group.The level of HO-1 in mRNA and protein increased in different degrees (P<0.05, P<0.01). Levels of Nrf2, HO-1 mRNA in Gastrodiae Rhizoma powder treatment group was significantly higher than that in Gastrodiae Rhizoma powder group (P<0.05). There was no significant difference in the expression of Nrf2, HO-1 protein.There was no significant difference in mRNA and protein levels of Keap1 among different groups. Conclusion::Morris water maze test and other results showed that Gastrodiae Rhizoma powder could improve the learning and memory ability of APP/PS1 mice, and it may enhance the expression of downstream antioxidant genes by regulating Keap1-Nrf2/HO-1 pathway.And then improve the learning and memory ability of APP/PS1 mice.

Effect of Baihe Gujin Tang on LPS-induced Acute Lung Injury in Mice Based on Nrf2/Keap1/p62 Signaling Pathway / 中国实验方剂学杂志

Objective:To investigate the protective effect and mechanism of Baihe Gujin Tang on lipopolysaccharide induced acute lung injury (LPS-ALI). Method:KM mice were randomly divided into 5 groups:blank control group, model group, dexamethasone 0.002 g·kg-1 group, Baihe Gujin Tang (0.417, 1.25 g·kg-1) group. Except for the blank control group, the other groups were given LPS to induce the mouse ALI model. Except for the blank control group and the model group, the other groups were continuously given intragastric administration for 7 days on the 1st to 7th days before modeling. The lung tissue of the mice was taken 6 h after modeling, and the wet/dry mass ratio (W/D) of the left lung was measured. The serum levels of superoxide dismutase(SOD), malondialdehyde (MDA),reactive oxygen species (ROS)and nitric oxide (NO) were detected in the mice. Thepathological changes of the lung tissues were observed by hematoxylin-eosin(HE) staining. The expression levels of nuclear factor E2 related factor 2(Nrf2), Kelch-likeECH-associated protein 1 (Keap1), p62 and autophagy associated proteinsLC3Ⅱ proteins in the lung tissues were detected by Western blot. Result:Compared with the blank control group, the W/D of the model group was significantly increased (PPPP-1 group was significantly lower (P-1 group and dexamethasone group were able to significantly inhibited MDA levels in serum (PPPPPPConclusion:Baihe Gujin Tang has obvious protective effect on LPS-ALI mice, and its mechanism may be related to the regulation of Nrf2/Keap1/autophagy feedback loop.

Effect of Yiqi Huoxue Recipe on Oxidative Stress Response in Rats with Cerebral Ischemia Injury Based on Nrf2/HO-1 Signaling Pathway / 中国实验方剂学杂志

Objective:To investigate the protective effect of Yiqi Huoxue recipe on rats with cerebral ischemia injury by using oxidative stress injury as an entry point. Method:SD rats were randomly divided into model group, sham operation group, nimodipine group (20 mg·kg-1), Yiqi Huoxue recipe high, medium and low dose group (2.916,1.458,0.729 g·kg-1). After 14 days of stomach, acute cerebral ischemic injury model was established by ligation of bilateral common carotid arteries. Ultrasound of synapse was observed by transmission electron microscopy. Total superoxide dismutase (T-SOD) and dialdehyde (MDA), lactate dehydrogenase (LDH), glutathione peroxidase (GSH-Px), horizontal adenine nucleoside triphosphate (ATP) levels were detected by biochemical method. Western blot and Real-time PCR was used to determine the expression of heme oxygenase-1(HO-1) and nuclear factor E2-related factor 2 (Nrf2) protein and mRNA in the ischemic cortex of rats. Result:Transmission electron microscopy showed that Yiqi Huoxue recipe had a significant improvement on the degree of cerebral ischemic injury. Compared with sham operation group, MDA levels in the brain homogenate of model group increased significantly, T-SOD and GSH-Px levels were significantly decreased (P+-K+-ATP ase, Ca2+-Mg2+-ATP ase and ATP was significantly decreased (PPPPP+-K+-ATP ase, Ca2+-Mg2+-ATP ase and total ATP activity(PPPPPPConclusion:Yiqi Huoxue recipe may protect against cerebral ischemic injury by inhibiting oxidative stress through Nrf2/HO-1 signaling pathway.

Effect of Klotho protein on renal oxidative stress in rat with calcium oxalate nephrolithiasis / 中华泌尿外科杂志

Objective To investigate the protective effect and mechanism of Klotho protein on oxidative stress in renal tubular epithelial cells of experimental rat nodels of renal calcium oxalate stone.Methods The 30 SD rats,6-8 weeks old,were randomly divided into 3 groups (10 of each),normal control group(group A),calcium oxalate model group(group B),drug plus calcium oxalate model group (group C).Group A was established with physiological saline by garage each day,group B was established with 1％ ethylene glycol in drinking water + 2％ ammonium chloride by garage (2 ml/d),group C was established with Fosinopril 2.5mg + Valsartan 15mg aqueous solution 2 ml by gavage on the basis of group B (2 ml/d).4 weeks later,the level of malondialdehyde (MDA),superoxide dismutase (SOD),catalase (CAT) and glutathione peroxidase (GSH) in the kidney homogenate were measured by double antibody sandwich enzyme-linked immunosorbent assay (ELISA),Polymerase chain reaction (RT-PCR) was used to measure expression of Klotho and Nrf2 mRNA,and Western Blot was used to measure the expression of Klotho and Nrf2 protein.Results The level of MDA in group B [(12.43 ± 0.43) μmol/mg] was significantly increased compared to group A[(8.67 ±0.84) μmol/mg,P ＜0.05] and group C [(7.97 ±0.81) μmol/mg,P＜0.05],while group A was close to group C (P ＞0.05).In group A,B,and C,the levels of SOD were (247.89 ± 2.45),(109.54 ± 4.21),and (189.74 ± 10.47) U/mg,respectively;the levels of GSH were (38.98 ± 4.55),(26.87 ± 3.92),and (31.29± 2.54) μmol/mg,respectively;CAT were (138.47 ± 8.74),(119.87 ± 8.45),and (127.46 ± 7.45) U/mg,respectively.The levels of SOD,GSH,CAT in group B were significantly lower than that in group A and C,while those in group B were close to group A (P ＞ 0.05).The expression of Klotho and Nrf2 mRNA in group B [(0.208 ± 0.036) and (0.499 ± 0.086)] were significantly lower than group A (1.011 ± 0.174 and 1.023 ± 0.139,P ＜ 0.05)and group C(1.123 ±0.248 and 1.023 ±0.139,P ＜0.05).The expression of Klotho and Nrf2 protien were also significantly lower than that in group A and C (P ＜0.05).Conclusions Valsartan and Fosinopril could prevent the formation of renal CaOx stones by upregulating expression of low level Klotho gene induced by ethylene glycol.This effect may be involved with activation of Keapl-Nrf2-ARE signaling pathway.