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.

Protective Effect of Alcohol Extract of Phyllanthi Fructus on Silicosis Mice and Its Correlation with Nrf2/ARE Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo explore the effect and underlying mechanism of alcohol extract of Phyllanthi Fructus on silicosis mice induced by silicon dioxide （SiO2）. MethodThirty-six male Kunming mice of SPF grade were randomly divided into a blank group，a model group，high-， medium， and low-dose Phyllanthi Fructus groups （800， 400， 200 mg·kg-1），and a tetrandrine group （0.039 mg·kg-1），with six mice in each group. The silicosis model was induced by static SiO2 exposure in mice except for those in the blank group. After 28 days of administration by gavage，the lung tissues were collected and the organ coefficient was calculated. Hematoxylin-eosin（HE）staining and Masson staining were used to detect the morphology of lung tissues. The content of hydroxyproline （HYP），superoxide dismutase （SOD），malondialdehyde （MDA）， and catalase （CAT） in serum was detected by enzyme-linked immunosorbent assay （ELISA）. Western blot and Real-time polymerase chain reaction（Real-time PCR） were used to detect the protein and mRNA expression of nuclear factor E2-related factor 2 （Nrf2），heme oxygenase-1 （HO-1），NAD（P）H：quinone oxidoreductase 1 （NQO1），and Kelch-like ECH-associated protein 1 （Keap1）， respectively. ResultCompared with the blank group，the model group showed seriously damaged morphological structure of lung tissues with inflammatory cell infiltration and fibrous tissue proliferation， reduced serum content of SOD and CAT（P<0.01），increased content of HYP and MDA（P<0.01）， down-regulated protein and mRNA expression of Nrf2，HO-1， and NQO1（P<0.01），and up-regulated protein and mRNA expression of Keap1 （P<0.05，P<0.01）. Compared with the model group，the high- and medium-dose Phyllanthi Fructus groups showed significantly restored morphological structure of lung tissues with reduced collagen deposition， increased serum content of SOD and CAT（P<0.05，P<0.01），decreased content of HYP and MDA（P<0.01）， up-regulated protein and mRNA expression of Nrf2，HO-1， and NQO1 （P<0.05，P<0.01），and down-regulated protein and mRNA expression of Keap1（P<0.05，P<0.01）. ConclusionThe alcohol extract of Phyllanthi Fructus can inhibit pulmonary fibrosis in silicosis mice，and the underlying mechanism may be related to the regulation of the Nrf2/antioxidant response element （ARE） signaling pathway.

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.

Protective Mechanism of Total Flavonoids of Lavender Against Skin Photoaging in Mice / 中国实验方剂学杂志

ObjectiveTo study the protective effect of total flavonoids of lavender on skin photoaging induced by ultraviolet B （UVB） in mice and to explore its mechanism from the perspective of nuclear factor E2-related factor 2 （Nrf2） antioxidant pathway. MethodEighty-four female KM mice were randomly divided into seven groups， namely blank group， model group， solvent group， vitamin E （0.013 g·kg-1） group， as well as low-， middle-， and high-dose （0.25， 1.25， 2.50 g·kg-1） groups of total flavonoids of lavender. The naked skin on the back of mice was irradiated with UVB for inducing optical damage. Thirty minutes before irradiation， the skin was coated with the total flavonoids of lavender. After continuous irradiation for one week， the skin moisture and elasticity on the back of mice were evaluated， and the effects of total flavonoids of lavender on histopathological changes in mouse skin were investigated by hematoxylin-eosin （HE） and Van Gieson （VG） staining. The levels of malondialdehyde （MDA）， superoxide dismutase （SOD）， total antioxidant capacity （T-AOC）， nitric oxide synthase （NOS）， and glutathione peroxidase （GSH-Px） after skin homogenization were detected by colorimetry， the inflammatory factors interleukin-1 （IL-1）， interleukin-6 （IL-6） and tumor necrosis factor-α （TNF-α） in skin tissue by enzyme-linked immunosorbent assay （ELISA）， and the mRNA expression levels of Nrf2， Kelch-like epichlorohydrin-associated protein 1 （Keap1）， BTB-CNC homology 1 （Bach1）， heme oxygenase-1 （HO-1）， quinone oxidoreductase 1 （NQO1）， and glutamate-cysteine ligase catalytic subunit （GCLC） by real-time polymerase chain reaction （Real-time PCR）. ResultCompared with the blank group， the model group exhibited significantly increased appearance score （P<0.01）， reduced skin moisture and elasticity （P<0.01）， pronounced pathological changes in the skin tissue like epidermal thickening， scabbing， small abscess， and severe injury， elevated MDA， NOS， IL-1， IL-6 and TNF-α （P<0.05， P<0.01）， lowered SOD， T-AOC， Nrf2， Keap1， NQO1 and GCLC mRNA expression （P<0.05，P<0.01）， and up-regulated Bach1 mRNA expression （P<0.01）. Compared with the model group， the total flavonoids of lavender at the low， middle， and high doses all remarkably reduced the appearance score （P<0.01）， enhanced the skin moisture and elasticity （P<0.01）， diminished the MDA， NOS， IL-1， IL-6， and TNF-α （P<0.05， P<0.01）， increased SOD， T-AOC， Nrf2， Keap1， NQO1， HO-1 and GCLC mRNA expression （P<0.05， P<0.01）， and down-regulated the expression of Bach1 mRNA （P<0.01）. ConclusionThe protective effect of the total flavonoids of lavender against skin photoaging in mice is significant， which may be related to its activation of Keap1/Nrf2/ARE signaling pathway， regulation of oxidative stress， and improvement of inflammatory response.

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.

Effect and Mechanism of Banxia Xiexintang on Rats with Chronic Atrophic Gastritis Based on Keap1/Nrf2/ARE Signaling Pathway / 中国实验方剂学杂志

Objective:To explore the mechanism of Banxia Xiexintang （BXXX） in preventing and treating chronic atrophic gastritis （CAG） through Kelch-like ECH-associated protein 1 （Keap1）/nuclear factor erythroid 2-related factor 2 （Nrf2）/antioxidant response element （ARE） signaling pathway. Method:SD rats were divided into a normal group （<italic>n</italic>=12） and an experimental group for CAG model induction. The model rats were then randomly divided into a model group， a vatacoenayme （VG） group （60 mg·kg^-1）， and high- （280 mg·kg^-1）， medium- （140 mg·kg^-1）， and low-dose （70 mg·kg^-1） BXXX groups. The doses in the BXXX groups were equivalent to 28， 14， and 7 g·kg^-1 crude drugs. The rats in the normal group and the model group received distilled water at an equal volume， and those in the VG group and the BXXX groups were treated correspondingly by gavage. After 12 weeks of treatment， hematoxylin-eosin （HE） staining was carried out to observe pathological changes in the gastric mucosa of CAG rats. Western blot and real-time fluorescence-based quantitative PCR was used to detect the protein and mRNA expression levels of Nrf2， glutathione S-transferase （GST）， and NAD （P）H：quinone oxidoreductase 1 （NQO1） in the gastric mucosa of CAG rats. Result:Compared with the normal group， the model group showed increased protein and mRNA expression levels of Nrf2， NQO1， and GST in the gastric mucosa of the rats （<italic>P</italic><0.05）， atrophic gastric mucosa， and even intestinal metaplasia. The protein and mRNA expression levels of Nrf2， NQO1， and GST in the VG group and the high- and medium-dose BXXX groups were lower than those in the model group （<italic>P</italic><0.05）， and gastric mucosa atrophy and intestinal metaplasia were significantly improved， especially in the high-dose BXXX group. However， the effect in the low-dose BXXX group was not significant. Conclusion:BXXX can blunt the transcriptional activity of Nrf2， shut down Nrf2 signaling pathway， and reduce the expression levels of NQO1 and GST to achieve normal oxidation-anti-oxidation balance， which may be one of its action mechanisms in the treatment of CAG.

Effect and Mechanism of Shaofu Zhuyutang on Endothelial Injury of Rats with Cold Coagulation and Blood Stasis Syndrome Based on Nrf2/ARE Signaling Pathway / 中国实验方剂学杂志

Objective:To observe the effect of Shaofu Zhuyutang on nuclear factor erythroid-2-related factor 2 （Nrf2） /antioxidant response element （ARE） signaling pathway in blood vessels by establishing the model of rats with cold coagulation and blood stasis syndrome， and to explore the protective effect and mechanism of Shaofu Zhuyutang on vascular endothelial injury. Method:The 50 SPF rats were randomly divided into high dose group （4.8 g·kg-1）， middle dose group （2.4 g·kg-1）， low dose group （1.2 g·kg-1）， model group and normal group （ten of each group）. The rat model of cold coagulation and blood stasis syndrome was established by subcutaneous injection of epinephrine hydrochloride combined with ice bath. At the same time of modeling， the drug was administered by gavage. After 28 days of continuous administration， the hemorheology indexes were detected by automatic hemorheology instrument. Levels of nitric oxide （NO）， endothelin （ET）-1， superoxide dismutase （SOD）， glutathione （GSH-Px）， intercellular adhesion molecule-1（ICAM-1）， vascular cell adhesion molecule-1（VCAM-1）， von Willebrand factor （vWF） in serum were determined by ELISA. Hematoxylin and eosin （HE） staining was used to observe the endothelial injury of vascular tissue of thoracic aorta. The protein expression of Nrf2 and HO-1 in vascular tissue of thoracic aorta was detected by Western blot. Real-time fluorescence quantitative polymerase chain reaction（Real-time PCR）was used to observe the expression of Nrf2 and heme oxygenase-1 （HO-1） mRNA in vascular tissue of thoracic aorta. Result:Compared with the blank group， model group rats whole blood viscosity and plasma viscosity were significantly increased （P<0.05，P<0.01）， vWF， ICAM 1， VCAM 1 content increased significantly （P<0.01）， NO， SOD， gsh-px levels decreased significantly （P<0.01）， significantly increased the content of ET-1（P<0.01）， thoracic aorta vascular tissue Nrf2， HO-1 mRNA expression was significantly increased （P<0.01）， Nrf2 protein expression in the cell nucleus increased significantly （P<0.05）， The protein expression level of Nrf2 in cytoplasm was significantly decreased （P<0.05）， while the protein expression level of HO-1 was significantly increased （P<0.01）. Compared with model group， the whole blood viscosity （high and middle cut）， plasma viscosity， were significantly reduced in high and meduim-dose Shaofu Zhuyutang groups（P<0.05，P<0.01）. The levels of vWF， ICAM-1， VCAM-1 and ET-1 in serum were significantly reduced （P<0.05，P<0.01）， NO， SOD and GSH-Px increased significantly （P<0.05，P<0.01）. The pathological changes such as hyperplasia， swelling and shedding of endothelial cells of thoracic aorta， rupture of internal elastic membrane and disorder of smooth muscle arrangement were improved. The expression levels of Nrf2， HO-1 protein and gene were significantly increased in vascular tissue of thoracic aorta （P<0.01）. Conclusion:Shaofu Zhuyutang has a protective effect on vascular endothelial injury in rats with cold coagulation and blood stasis syndrome. The mechanism of action is related to the activation of Nrf2/ARE signaling pathway， which leading to the increased expression of antioxidant enzymes and decreased the expression of adhesion factors.

4′-O-β-D-Glucosyl-5-O-Methylvisamminol Attenuates Pro-Inflammatory Responses and Protects against Oxidative Damages

We attempted to examine anti-inflammatory and anti-oxidant effects of 4′-O-β-D-glucosyl-5-O-methylvisamminol (GOMV), the first epigenetic inhibitor of histone phosphorylation at Ser10. While GOMV did not affect the viability of murine macrophage RAW 264.7 cells, it significantly suppressed lipopolysaccharide (LPS)-induced generation of prostaglandin E₂ (PGE₂) and nitric oxide (NO) through transcriptional inhibition of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). GOMV also scavenged free radicals in vitro, increased NF-E2-related factor 2 (NRF2), and activated antioxidant response element (ARE), thereby resulting in the induction of phase II cytoprotective enzymes in human keratinocyte HaCaT cells. Finally, GOMV significantly protected HaCaT cells against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced oxidative intracellular damages. Together, our results illustrate that GOMV possesses anti-inflammatory and anti-oxidant activity.