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.

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.