[Protective effect of ginsenoside Rg_1 aganist diabetic retinopathy by inhibiting NLRP3 inflammasome in type 2 diabetic mice].

Ginsenoside Rg_1, one of the main active components of precious traditional Chinese medicine Ginseng Radix et Rhizoma, has the anti-oxidative stress, anti-inflammation, anti-aging, neuroprotection, and other pharmacological effects. Diabetic retinopathy(DR), the most common complication of diabetes, is also the main cause of impaired vision and blindness in the middle-aged and the elderly. The latest research shows that ginsenoside Rg_1 can protect patients against DR, but the protection and the mechanism are rarely studied. This study mainly explored the protective effect of ginsenoside Rg_1 against DR in type 2 diabetic mice and the mechanism. High fat diet(HFD) and streptozotocin(STZ) were used to induce type 2 diabetes in mice, and hematoxylin-eosin(HE) staining was employed to observe pathological changes in the retina of mice. The immunohistochemistry was applied to study the localization and expression of nucleotide-binding oligomerization domain-like receptors 3(NLRP3) and vascular endothelial growth factor(VEGF) in retina, and Western blot was used to detect the expression of nuclear factor-kappa B(NF-κB), p-NF-κB, NLRP3, caspase-1, interleukin-1ß(IL-1ß), transient receptor potential channel protein 6(TRPC6), nuclear factor of activated T-cell 2(NFAT2), and VEGF in retina. The results showed that ginsenoside Rg_1 significantly alleviated the pathological injury of retina in type 2 diabetic mice. Immunohistochemistry results demonstrated that ginsenoside Rg_1 significantly decreased the expression of NLRP3 and VEGF in retinal ganglion cells, middle plexiform layer, and outer plexiform layer in type 2 diabetic mice. According to the Western blot results, ginsenoside Rg_1 significantly lowered the expression of p-NF-κB, NLRP3, caspase-1, IL-1ß, TRPC6, NFAT2, and VEGF in retina of type 2 diabetic mice. These findings suggest that ginsenoside Rg_1 can significantly alleviate DR in type 2 diabetic mice, which may be related to inhibition of NLRP3 inflammasome and VEGF. This study provides experimental evidence for the clinical application of ginsenoside Rg_1 in the treatment of DR.

Ginsenoside Rg1 protects against H2O2­induced neuronal damage due to inhibition of the NLRP1 inflammasome signalling pathway in hippocampal neurons in vitro.

Oxidative stress and neuroinflammation are important in the pathogenesis of ageing and age­related neurodegenerative diseases, including Alzheimer's disease. NADPH oxidase 2 (NOX2) is a major source of reactive oxygen species (ROS) in the brain. The nucleotide­binding oligomerisation domain (NOD)­like receptor protein 1 (NLRP1) inflammasome is responsible for the formation of pro­inflammatory molecules in neurons. Whether the NOX2­NLRP1 inflammasome signalling pathway is involved in neuronal ageing and age­related damage remains to be elucidated. Ginsenoside Rg1 (Rg1) is a steroidal saponin found in ginseng. In the present study, the primary hippocampal neurons were treated with H2O2 (200 µM) and Rg1 (1, 5 and 10 µM) for 24 h to investigate the protective effects and mechanisms of Rg1 on H2O2­induced hippocampal neuron damage, which mimics age­related damage. The results showed that H2O2 treatment significantly increased ROS production and upregulated the expression of NOX2 and the NLRP1 inflammasome, and led to neuronal senescence and damage to hippocampal neurons. Rg1 decreased ROS production, reducing the expression of NOX2 and the NLRP1 inflammasome in H2O2­treated hippocampal neurons. Furthermore, Rg1 and tempol treatment significantly decreased neuronal apoptosis and the expression of ß­galactosidase, and alleviated the neuronal senescence and damage induced by H2O2. The present study indicates that Rg1 may reduce NOX2­mediated ROS generation, inhibit NLRP1 inflammasome activation, and inhibit neuronal senescence and damage.

Biochanin A Protects Against Lipopolysaccharide-Induced Damage of Dopaminergic Neurons Both In Vivo and In Vitro via Inhibition of Microglial Activation.

Neuroinflammation has been reported to be involved in the pathogenesis of Parkinson's disease (PD). Inhibition of microglia-mediated neuroinflammation might be a potential strategy for PD treatment. Biochanin A, is an O-methylated isoflavone, classified as a kind of phytoestrogens due to its chemical structure that is similar to mammalian estrogens. It has been found to possess antifibrotic, antiapoptotic, and antioxidant effects. In the present study, we investigated the neuroprotective effects of biochanin A on lipopolysaccharide (LPS)-induced dopaminergic neurons damage both in vivo and in vitro and the related molecular mechanisms. The results showed that biochanin A treatment for 21 days significantly attenuated the behavioral dysfunction of PD rats, prevented dopaminergic neurons damage, and inhibited activation of microglia in the LPS-induced PD rats. Furthermore, biochanin A decreased the levels of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in the serum, and inhibited the phosphorylation of ERK, JNK, p38 in the substantia nigra of PD rats. In vitro test, biochanin A also inhibited primary microglial activation and protected dopaminergic neurons, decreased the content of nitric oxide, IL-1ß, and TNF-α in supernatants, and inhibited the reactive oxygen species production. Taken together, these results suggest that biochanin A exerts protective effects on LPS-induced PD rats, and the mechanisms may be associated with the inhibition of inflammatory response and the MAPK signaling pathway.

Anti­fibrotic effects of Acremoniumterricola milleretal mycelium on immunological hepatic fibrosis in rats.

Acremoniumterricola milleretal mycelium (AMM) exerts numerous protective effects on organs, and has been used in Chinese herb prescriptions to treat refractory diseases. The aim of this study was to investigate the effects of AMM on immunological hepatic fibrosis induced by porcine serum (PS) in rats. Male Sprague Dawley rats were administered 0.5 ml sterile PS by intraperitoneal injections twice a week for 18 weeks. AMM (175, 350 or 700 mg/kg) and colchicine (0.1 mg/kg) were administered intragastrically each day until the rats were sacrificed. PS administration resulted in marked hepatic fibrosis, as assessed by increased oxidative stress and hepatic collagen content, as well as α­smooth muscle actin (α­SMA) expression. AMM significantly reduced liver damage and fibrosis. In addition, AMM decreased the elevation in hydroxyproline, hyaluronic acid, laminin and procollagen type III; increased the activity of superoxide dismutase and glutathione peroxidase; decreased α­SMA expression; and eliminated hepatic collagen deposits. Furthermore, AMM inhibited Smad2/3 phosphorylation and Smad7 expression. These results indicate that AMM is able to reduce oxidative stress, inhibit collagen synthesis and block the transforming growth factor­ß/Smad signaling pathway in a dose­dependent manner.

[Protective effect and mechanism of astragaloside IV on oxidative stress injury of mesangial cells].

OBJECTIVE: To study the protective effect of astragaloside IV (AS IV) on H2O2 induced human mesangial cells (HMC), and further explore its molecular mechanism. METHOD: The cultured mesangial cells were divided into 5 groups: the normal control group, the H2O2 model group, the AS IV (12.5, 100 nmol x L(-1)) group and the Tempol (1 x 10(5) nmol x L(-1)) group. The MTT method was used to observe cell viability. Hoechst 33258 staining was used to observe the HMC apoptosis and DHE staining was used to detect the generation of reactive oxygen species (ROS). The flow cytometry was used to detect the changes in cell cycle. Western blot was used to detect the expression of Cyclin D1, CyclinA, p38, and T-p38. RESULT: H2O2 (1 x 10(5), 2 x 10(5), 3 x 10(5), and 4 x 10(5) nmol x L(-1)) could induce HMC oxidative stress injury, with significant decrease in the cell survival rate. AS IV (100 nmol x L(-1)) could significantly inhibit HMC oxidative stress injury induced by H2O2 (3 x 10(5) nmol x L(-1)), increase the survival rate of HMC cells, inhibit cell apoptosis, and decrease intracellular ROS production. AS IV could also increase the expression of Cyclin D1, recover normal cell proliferation, and decrease the expression of p38. CONCLUSION: AS IV can protect H2O2 induced oxidative stress injury in mesangial cells. Its mechanisms may be related to inhibiting the p38/MAPK signaling pathway, increasing the expression of Cyclin D1 and decreasing the intracellular ROS oxidative stress injury.

[Effects of astragalosides on PC12 cells injury and APP expression induced by dexamethasone and Abeta(25-35)].

OBJECTIVE: To study the effects of Astragaloside (AST) on PC12 cells injury and APP expression induced by dexamethasone (DEX) and beta-amyloid protein 25-35 (Abeta(25-35). METHODS: Logarithmic growth phase of the PC12 cells were seeded in culture plates. DEX 5 micromol/L and Abeta(25-35) 1 micromol/L were used to induce PC12 cells injury. MTT assay was used to detect the PC12 cells activity. RT-PCR was used to detect the APP, alpha-secretase and beta-secretase mRNA level of PC12 cells. Western bloting was used to detect APP protein expression of PC12 cells. RESULTS: MTT results showed that, DEX and Abeta(35-35) co-application could significantly decrease PC12 cells activity (P5 < 0.01). AST (10.20 mg/L) and Ginsenoside Rg1 (16 micromol/L) could increase PC12 cells activity. RT-PCR analysis showed that DEX and Abeta(25-35) co-application could significantly increase the beta-secretase mRNA levels and APP770, lower alpha-secretase mRNA levels. AST (10.20 mg/L) and Rg1 could decrease the elevated APP770, beta-secretase mRNA levels and increase the alpha-secretase mRNA level of PCl2 cells. Western bloting analysis result showed that AST (10.20 mg/L) and Rg1 could decrease the APP expression of PC12 cells induced by DEX and Abeta(25-35). CONCLUSION: AST has protective effects on PC12 cell injury induced by DEX and Abeta(25-35). The mechanism may be associated with decreasing the beta-secretase mRNA levels and APP expression, increasing the alpha-secretase mRNA levels.

Protective effect of extract of Astragalus on learning and memory impairments and neurons' apoptosis induced by glucocorticoids in 12-month-old male mice.

Alzheimer's disease (AD) is a chronic neurodegenerative disorder marked by a progressive loss of memory and cognitive function. Stress-level glucocorticoids are correlated with dementia progression in patients with AD. In this study, 12-month male mice were chronically treated with stress-level dexamethasone (DEX, 5 mg/kg) and extract of Astragalus (EA, 10, 20, and 40 mg/kg) or Ginsenoside Rg1 (Rg1, 6.5 mg/kg) for 21 days. We investigated the protective effect of EA against DEX injury in mice and its action mechanism. Our results indicate that DEX can induce learning and memory impairments and neuronal cell apoptosis. The mRNA levels of caspase-3 are selectively increased after DEX administration. The results of immunohistochemistry demonstrate that caspase-3 and cytochrome c in hippocampus (CA1, CA3) and neocortex are significantly increased. Furthermore, DEX treatment increased the activity of caspase-9 and caspase-3. Treatment groups with EA (20 and 40 mg/kg) or Rg1 (6.5 mg/kg) significantly improve learning and memory, downregulate the mRNA level of caspase-3, decrease expression of caspase-3 and cytochrome c in hippocampus (CA1, CA3) and neocortex, and inhibit activity of caspase-9 and caspase-3. The present findings highlight a possible mechanism by which stress level of DEX accelerates learning and memory impairments and increases neuronal apoptosis and the potential neuronal protection of EA.

[Effects of ginkgolide on hemodynamics in myocardial ischemic dogs].

OBJECTIVE: To investigate the effects of Ginkgolide on hemodynamics and myocardial oxygen metabolism in acute myocardial ischemic dogs. METHODS: Acute myocardial ischemic model dogs were established by ligating left anterior descending coronary artery (LAD). Some hemodynamic parameters and cardiac oxygen consumption were observed after Ginkgolide were given to dogs through the duodenum. RESULTS: Ginkgolide could increase LVSP, + dp/dt(max), LVWI, SW, CO and CBF, decrease TPVR, CVR, MVO2 and MOUR of Acute myocardial ischemic model dogs at different time points after ligation of LAD. CONCLUSION: Ginkgolide can improve the hemodynamic conditions and oxygen metabolism of myocardial ischemic dogs.

Protective effect of astragaloside on focal cerebral ischemia/reperfusion injury in rats.

This study was to observe the neurological protective effects of astragalosides (AST) on focal cerebral ischemia-reperfusion (I/R) injury in rats and to explore its possible mechanism. Male SD rats received right middle cerebral artery occlusion for 120 min and AST (40 mg/kg) was orally administered. The rats were decapitated 1, 3, 7, and 14 days after reperfusion. The neurological deficit score, infarct volume and water content of brain were measured; the activity of superoxide dismutase (SOD), lactate dehydrogenase (LDH) and nitric oxide synthase (NOS), and the content of malondialdehyde (MDA), lactate (LD) and nitric oxide (NO) of brain tissue were detected too. The expression of inducible nitric synthase (iNOS), nerve growth factor (NGF) and tropomyosin receptor kinase A (TrkA) mRNA were measured by RT-PCR or real-time PCR. AST could significantly reduce the neurological deficit score; infract volume and water content, increase SOD and LDH activities, decrease NOS activity and MDA, LD and NO content. AST treatment could down-regulate expression of iNOS mRNA, while, NGF and TrkA mRNA were up-regulated. Our data suggest that AST have the protective effects on focal cerebral ischemia in rats at the different reperfusion time points, the mechanism may be related to the antioxidation, regulated the expressions of iNOS, NGF and TrkA mRNA.

[Protective effects of Shexiang Xingnaonin on focal cerebral ischemia/reperfusion injury and mechanism].

OBJECTIVE: To study the protective effects of Shexiang Xingnaonin (SXN) on focal cerebral ischemia/reperfusion injury and its mechanism. METHOD: Middle cerebral artery occlusion (MCAO) was used to make focal cerebral ischemia/reperfusion model by in travascular nylon filament occlusion. The protective effects of SXN at different doses were evaluated by investigating neurological function score, pathomorphology of brain, the ultrastructure of neuron, expression of tumor necrosis factor-alpha, thrombogenesis in vitro, platelet aggregation and lysing effect of blood clot in vitro. RESULT: Compared with model group, SXN (0.08, 0.16 g x kg(-1)) could decrease the neurological score, improve pathomorphology and neuron ultrastructure of brain, inhibit the expression of TNF-alpha, decrease the length, wet weight and dry weight of thromb and inhibit platelet aggregation. And SXN (0.16, 0.32 g x L(-1)) could dissolve blood clot in vitro. CONCLUSION: SXN has protective effects on focal cerebral ischemia/reperfusion injury. The role of inhibit the expression of TNF-alpha, inhibit thrombogenesis and platelet aggregation might contribute to its neuroprotective effects.

[Effects of AST and ASI on metabolism of free radical in senescent rats treated by HC].

OBJECTIVE: To study the effects of Astragaloside (AST) and Astragalus Saponin I (ASI) on metabolism of free radical and immune function in senescent rats treated by HC. METHOD: Hydrocorisone (HC) was used to estabilsh the aging model in rats. The content of molondialdehyde (MDA), glutathoine (GSH) and oxidized glutathoine (GSSG) in liver and brain was detected according to kit. The activity of Mn superoride dismulase (Mn-SOD) and catalase (CAT) was also surveyed by kit. Concanavalin (ConA) was used to detect the proliferation and interleukin-2 (IL-2) production of splenocytes. RESULT: Compared with HC control, AST and ASI could decrease the content of MDA, GSH and GSSG in liver and brain, increase the activity of Mn-SOD and CAT, and promote the proliferation and interleukin-2 (IL-2) activity of splenocytes. CONCLUSION: AST and ASI could delay the aging effect in rats treated by HC, and its mechanism maybe the antioxidant and regulating immunity.