Effects of 2,4-dichlorophenoxyacetic acid on the expression of NLRP3 inflammasome and autophagy-related proteins as well as the protective effect of Lycium barbarum polysaccharide in neonatal rats.

The pesticide 2,4-dichlorophenoxyacetic acid (2,4-D) has neurotoxic effects, but its mechanism is not clear. In this study, a 2,4-D (75 mg/kg. b.w) exposure model was established in SD rats with colostrum. Lipopolysaccharide (1 mg/kg b.w) was used as the positive control, and Lycium barbarum polysaccharide (LBP, 50 mg/kg b.w) was used as an intervention factor to explore the neurotoxic effect of 2,4-D and the neuroprotective effect of LBP. Our research results show that 2,4-D causes a decrease in the number of hippocampal CA3 pyramidal cells and pyknosis in nuclei with a triangular or irregular shape and that rats show signs of anxiety or depression. In rat serum, superoxide dismutase, and glutathione peroxidase activity decreased, while malondialdehyde content increased. Protein and mRNA levels of TNFα, IL-6, IL-1ß, IL-18, NLRP3, ASC, caspase-1, IL-1ß, IL-18, and p62 increased, while those of LC3-II/LC3-I and Beclin-1 decreased in hippocampal tissues. In conclusion, 2,4-D increased the oxidative stress level, induced neuroinflammatory response, and decreased the autophagy level in experimental rats. LBP may have upregulated the autophagy level in the body by inhibiting the activation of the NLRP3 inflammasome, thus playing a neuroprotective role.

Lycium barbarum polysaccharides attenuate cardiovascular oxidative stress injury by enhancing the Keap1/Nrf2 signaling pathway in exhaustive exercise rats.

Moderate exercise is beneficial to physical and mental health. When the amount of exercise and exercise intensity exceeds a certain limit and reaches the state of exhaustion, oxidative stress levels in the body increase, which can lead to oxidative stress­associated damage. Lycium barbarum polysaccharide (LBP) is one of the primary active ingredients extracted from wolfberry. Following exhausting exercise in rats, LBP supplements decrease damage to the myocardium and blood vessels, indicating that LBP exerts a protective effect on the cardiovascular system. The Kelch­like ECH­associated protein 1 (Keap1)/NF­E2­related factor 2 (Nrf2) anti­oxidative stress signaling pathway improves total oxidizing ability; anti­apoptosis and other aspects serve a vital role. In the present study, LBP intervention was performed in vivo and in vitro to observe its effect on the Keap1/Nrf2 pathway and oxidative stress­associated indicators in order to clarify its protective mechanism. For the in vivo experiments, 60 male Sprague­Dawley rats were randomly divided into normal control and aerobic, exhaustive and exhaustive exercise + LBP (200 mg/kg/day) groups. For the in vitro experiments, a rat thoracic aortic endothelial cell (RTAEC) oxidative stress model was established using angiotensin II (AngII) and divided into blank control, LBP (3,200 µg/ml), AngII (1x10­4 mol/l) and AngII + LBP groups. For in vitro experiments, small interfering (si)RNA (50 nmol) was used to transfect RTAEC and induce gene silencing of Nrf2. ELISA, hematoxylin and eosin staining, TUNEL, immunofluorescence, western blotting, immunohistochemistry and reverse transcription­quantitative PCR were used to evaluate and verify the effect of LBP on oxidative stress indicators and the expression of Keap1/Nrf2 antioxidative stress signaling pathway. The in vivo experiments showed that LBP decreased the expression of serum malondialdehyde (MDA) and AngII, as well as apoptosis of blood vessels and cardiomyocytes and expression of TNF­α in rats following exhaustive exercise. Meanwhile, LBP enhanced expression of the Keap1/Nrf2 signaling pathway and downstream associated protein glutamyl­cysteine synthetase catalytic subunit (GCLC), quinone oxidoreductase 1 (NQO1) and glutamate­cysteine ligase modified subunit (GCLM) in the thoracic aorta and myocardium of rats following exhaustive exercise. In RTAEC in vitro, LBP decreased the expression of MDA and TNF­α in the supernatant, promoted the nuclear translocation of Nrf2 and increased expression levels of GCLC, NQO1 and GCLM. Following siNrf2 transfection into endothelial cells, the anti­inflammatory and antioxidant stress effects of LBP were decreased. LBP was found to enhance the expression of the Keap1/Nrf2 antioxidant stress signaling pathway in endothelial cells, decreasing oxidative stress and the inflammatory response. Moreover, LBP improved the antioxidant stress ability of endothelial cells and alleviated injury of myocardial vascular tissue, thereby protecting the cardiovascular system.

Role of EGFR/ErbB2 and PI3K/AKT/e-NOS in Lycium barbarum polysaccharides Ameliorating Endothelial Dysfunction Induced by Oxidative Stress.

Lycium barbarum polysaccharides (LBP) are the major ingredients of wolfberry. In this study, we investigated the role of LBP in endothelial dysfunction induced by oxidative stress and the underlying mechanisms using thoracic aortic endothelial cells of rat (RAECs) as a model. We found that Ang II inhibits cell viability of RAECs with 10-6mol/L of Ang II treatment for 24h most potential (P<0.05), the level of reactive oxygen species (ROS) is increased by Ang II treatment (P<0.01), and the expression of Occludin and Zonula occludens-1 (ZO-1) is decreased by Ang II treatment (P<0.05). However, preincubation of cells with LBP could inhibit the changes caused by Ang II, LBP increased cell viability (P<0.05), decreased the level of ROS (P<0.01), and up-regulated the expression of Occludin (P<0.05) and ZO-1. In addition, Ang II treatment increased the expression of EGFR and p-EGFR (Try1172) and which can be inhibited by LBP. On the contrary, expression of ErbB2, p-ErbB2 (Try1248), PI3K, p-e-NOS (Ser1177) (P<0.05), and p-AKT (Ser473) (P<0.05) was inhibited by Ang II treatment and which can be increased by LBP. Treatment of the cells with inhibitors showed that the regulation of p-e-NOS and p-AKT expression by Ang II and LBP can be blocked by PI3K inhibitor wortmannin but not EGFR and ErbB2 inhibitor AC480. Taken together, our results suggested that LBP plays a critical role in maintaining the integrality of blood vessel endothelium through reduced production of ROS via regulating the activity of EGFR, ErbB2, PI3K/AKT/e-NOS, and which may offer a novel therapeutic option in the management of endothelial dysfunction.

Effects of Lycium barbarum polysaccharides on oxidative stress in hyperlipidemic mice following chronic composite psychological stress intervention.

Chronic composite psychological stress intervention is the accumulation of factors which may induce psychological stress, including food deprivation, water deprivation and swimming in cold water. Approximately 40% of cases of atherosclerosis are associated with chronic composite psychological stress. The aim of the present study was to explore the effects of Lycium barbarum polysaccharides (LBP) on blood lipid levels and oxidative stress in hyperlipidemic mice, following chronic composite psychological stress. A hyperlipidemic mouse model was generated, and the mice were subjected to chronic composite psychological stress and treated with LBP for 30 days. After 30 days the triglyceride (TG) and total cholesterol (TC) levels were measured in the serum, and the mRNA expression levels of cholesterol 7α­hydroxylase (CYP7A1) were determined in the liver, in order to observe any changes to lipid metabolism. The levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were measured in the liver to evaluate the effects of LBP on oxidative stress. The blood serum levels of interleukin­6 (IL­6) and heat shock protein 70 (HSP­70) were measured to evaluate the extent of the aortic inflammatory response, and to determine the protective effects of LBP. The levels of TG, TC, MDA and IL­6 were significantly higher in the mice subjected to chronic composite psychological stress (HS), as compared with the mice treated with LBP alone (HL), or treated with LBP and subjected to stress (HLS). In addition, SOD and HSP­70 levels, and the mRNA expression levels of CYP7A1 were significantly lower in the HS group, as compared with that in the HL and HLS groups. These results suggest that chronic composite psychological stress may promote the occurrence and development of atherosclerosis, by inducing the aortic inflammatory response and lipid peroxidation. Furthermore, treatment with LBP significantly inhibited oxidative stress and the aortic inflammatory response.

[Effects of Lycium barbarum on the behavior, body weight and TNF-alpha level of rat treated with binding].

OBJECTIVE: To explore the effects of Lycium barbarum (L) on the behavior and body weight and TNF-alpha level of rat treated with binding. METHODS: Rats were randomly divided into 6 groups: control group,binding group, 2.5% L group, 5.0% L group, 2.5% L plus binding group, 5.0% L plus binding group. Lycium barbarums were pressed into juice, then rats were fed with the drinking water contening juice. Rats were bound to restrict for 21 days. RESULTS: (1) The increases of serum-cortisol level and the decreases of body weight and the increases of TNF-alpha level of rats of binding group in comparision with control groups (P < 0.05) (2) Rats body weight gain, movement and TNF-alpha level in both of 2.5% L plus binding group and 5.0% L plus binding group were more higher than those in binding group (P < 0.05). Serum-cortisol level of these two groups were more lower and had statistical significance in comparison with those of binding groups (P < 0.05). CONCLUSION: Binding could suppress body weight gain and markedly reduce the activity and TNF-alpha level of rat. Lycium barbarum could be a good adjustment on the behavior, body weight and TNF-alpha.