Antibacterial activity and underlying mechanism of Meconopsis quintuplinervia Regel extract against the acne-causing bacteria Propionibacterium acnes and Staphylococcus aureus.

The aim of this study was to evaluate the antibacterial activity and underlying mechanism of ethanol extracts of Meconopsis quintuplinervia Regel (EMQ) against the acne-causing bacteria Propionibacterium acnes and Staphylococcus aureus. The study results indicated that EMQ was an effective antibacterial agent against P. acnes and S. aureus, with a DIZ of 14.5 and 13.2mm, MIC of 12.5 and 12.5mg/mL and MBC of 100 and 50mg/mL, respectively. EMQ induced morphological changes to bacterial cells, as determined by electron microscopy. Leakage of alkaline phosphatase and nucleic acids confirmed that EMQ compromised the membrane integrity of bacterial cells. Furthermore, protein analysis revealed that EMQ hindered total protein expression and lowered adenosine triphosphatase activity, while crystal violet staining revealed suppressed biofilm production. Bacterial adhesion analysis demonstrated that EMQ lowered the adhesive capacity of bacterial cells. The main chemical components of EMQ, identified by LC-MS, seem to have important roles in the antimicrobial effects against P. acnes and S. aureus, suggesting EMQ is a promising therapeutic for acne treatment.

Malus toringoides (Rehd.) Hughes Ameliorates Nonalcoholic Fatty Liver Disease with Diabetes via Downregulation of SREBP-1c and the NF-κB Pathway In Vivo and In Vitro.

Diabetic patients are more prone to developing nonalcoholic fatty liver disease (NAFLD) compared with healthy people. As a plant homologous to both medicine and food, Malus toringoides (Rehd.) Hughes has been used as an intervention for both NAFLD and diabetes. However, the effect and mechanism of M. toringoides on NAFLD on type 2 diabetes mellitus (T2DM) is unclear. The current investigation was designed to evaluate the ameliorative effects and mechanism of M. toringoides ethanol extract (CBTM-E375) on T2DM, and to identify the compounds in these extracts. The effects of CBTM-E375 on T2DM were verified using a high-fat diet-/streptozotocin-induced diabetic rat and free fatty acid (0.5 mM)-induced human hepatocellular carcinoma cell (HepG2) models. The components of CBTM-E375 were identified by high performance liquid chromatography-mass spectrometry/mass spectrometry. Our results demonstrate that CBTM-E375 ameliorated lipid accumulation (total cholesterol, triglyceride), oxidative stress (superoxide dismutase, catalase, malondialdehyde, glutathione peroxidase), and inflammation (tumor necrosis factor-α [TNF-α], interleukin [IL]-1ß, IL-6, C-reactive protein [CRP]) in vivo and in vitro, these effects were associated with a CBTM-E375-mediated downregulation of SREBP-1c (sterol regulatory element binding protein 1c) and the NF-κB (nuclear factor κB) signaling pathway. A total of 20 chemical compounds were identified in CBTM-E375, including phlorizin, isoquercitrin, chlorogenic acid, quercetin, naringenin, and trigonelline, which have been reported to have positive effects on diabetes or on NAFLD.

Ajania purpurea Extract Attenuates LPS-Induced Inflammation in RAW264.7 Cells and Peritonitis Mice.

Macrophages have important roles in the progression of inflammation. Ajania purpurea Shih. is a member of the Ajania Poljakor family that grows in Tibet (China). Extracts from plants in this genus have anti-bacterial and anti-inflammatory properties. However, there are few reports on the activity and mechanism of Ajania purpurea. Here, we confirmed the anti-inflammatory effect of Ajania purpurea Shih. ethanol extract (EAPS) by examining the levels of inflammatory factors in a mouse model of peritonitis and RAW264.7 cells. The main components of EAPS detected by LC-MS analysis included piperine and chlorogenic acid. In particular, in lipopolysaccharide (LPS)-induced RAW264.7 cells, EAPS inhibited the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-induced RAW264.7 cells, lowered the levels of nitric oxide (NO) and prostaglandin E2 (PGE2), as well as the release of inflammatory factors such as tumor necrosis factor-alpha (TNF-α) and pro-inflammatory cytokines such as interleukin (IL)-1ß and IL-6. In addition, Western blot analysis and immunofluorescence staining verified that EAPS inhibited the activity of the nuclear factor-kappaB (NF-κB) pathway by reducing the nuclear translocation of the p65 subunit. Furthermore, in a mouse model of peritonitis, EAPS inhibited the release of inflammatory factors, as well as the recruitment of immune cells including neutrophils and macrophages. These findings indicated that EAPS suppressed LPS-induced inflammation via inhibiting the NF-κB pathway in RAW264.7 cells and mice with peritonitis. Thus, EAPS may be a viable therapeutic method for the treatment of inflammation and related disorders.

Vascular Protective Effects of Malus toringoides (Rehd.) Hughes Extracts and their Mechanism in Diabetic Rats and HUVECs.

Malus toringoides (Rehd.) Hughes (Rosaceae) is used as a traditional folk medicine in the Tibet autonomous region of China to treat hypertension, hyperglycemia, and hyperlipidemia. However, few modern pharmacological data on the use of this plant against diabetic syndrome are available. In this study, we examined the vascular protection provided by a 70% ethanol extract of M. toringoides (EMT) in human umbilical vein endothelial cells (HUVECs) grown in high-glucose medium and in a high-fat diet/streptozotocin-induced rat diabetes model. EMT significantly suppressed the expression of cell adhesion molecules in both HUVECs and diabetic rats. EMT also inhibited activation of the CX3CL1/CX3CR1 axis and the nuclear factor kappa B (NF-κB) signaling pathway in vivo and in vitro. The results provide a significant information on the vasoprotective properties of M. toringoides that may contribute to the development and application of related herbal medicines.

Ethanol extract of Nepeta angustifoia C. Y. Wu ameliorates hyperuricemia in fructose-induced mice.

As a popular medicinal plant traditionally used in Tibet of China, Nepeta angustifolia C. Y. Wu is mainly administered to treat apoplexia, cerebral haemorrhage, fainting and epilepsy and other symptoms, while its effect on hyperuricemia is still unclear. In the present study, we evaluated the improvement of the 70% ethanol extract of Nepeta angustifolia C. Y. Wu in fructose-induced hyperuricemic mice. The results revealed that Nepeta angustifolia C. Y. Wu significantly decreased blood glucose and blood lipid levels, as well as lowering the urinary levels of uric acid, creatinine and urea nitrogen. Meanwhile, it effectively restored the serum levels of uric acid, creatinine and urea nitrogen and inhibited serum and hepatic XOD activities and renal oxidative stress, while suppressing the secretions of TNF-α, IL-1ß and IL-6 in kidney. Nepeta angustifolia C. Y. Wu also attenuated the infiltration of inflammatory cells and reduced the production and accumulation of glycogen and collagen, while restoring the dysregulated protein expressions of renal URAT1, GLUT9, OAT1 and OAT3. In summary, our results support the idea that Nepeta angustifolia C. Y. Wu is a promising agent for treating hyperuricemia.

Hepatoprotective effect of Sophora moorcroftiana (Benth.) Benth.Ex baker seeds in vivo and in vitro.

The leguminosae of Sophora moorcroftiana (Benth.) Benth.ex Baker is a drought-resistant endemic Sophora shrub species from the Qinghai-Tibet Plateau, and its seeds have hepatoprotective effects. To study the effect of S. moorcroftiana seeds on liver injury and the molecular mechanism underlying the beneficial effects, liquid chromatography-mass spectrometry was used to detect the main active components in the ethanol extract of S. moorcroftiana seeds (SM). Male mice were divided into six groups (n = 8): normal control (NC), CCl4, SM (50, 100, 200 mg/kg), and dimethyl diphenyl bicarboxylate (150 mg/kg) groups. Mice were treated as indicated (once/day, orally) for 14 days, and CCl4 (2 mL/kg) was administered intraperitoneally. The serum and liver of mice were used for biochemical assays. To explore the underlying mechanism, HepG2 cells were treated with SM, stimulated with tert-butyl hydroperoxide (t-BHP, 50 µM), and analyzed by Western blotting. The major active compounds of SM were alkaloids including 22 compounds. Serum alanine transaminase (ALT), aspartate transaminase (AST), and alkaline phosphatase (ALP) decreased in the SM (200 mg/kg) group. SM can activate the expression of pregnane X receptor (PXR) and downstream molecules cytochrome P4503A11 enzyme (CYP3A11), UDP glucuronosyltransferase 1 family polypeptide A 1 (UGT1A1), and inhibit the multidrug resistance protein 2 (MRP2). In addition, SM improved cell viability in t-BHP-induced HepG2 cells (64% to 83%) and decreased the activation of the mitogen-activated protein kinase (MAPK) pathway. The main compounds in SM were alkaloids. SM showed hepatoprotective effects possibly mediated by the suppression of oxidative stress through the MAPK pathway.

Nepeta angustifolia C. Y. Wu improves renal injury in HFD/STZ-induced diabetic nephropathy and inhibits oxidative stress-induced apoptosis of mesangial cells.

ETHNOPHARMACOLOGICAL RELEVANCE: As an important medicinal material constituting a variety of traditional Chinese medicine prescriptions, Nepeta angustifolia C. Y. Wu was used as a folk medicine to treat various vascular-related diseases including apoplexia, and cerebral haemorrhage in Tibet, China. Our previous studies have shown that this plant had a significant protective effect on vascular dysfunction of the intracerebral haemorrhage and diabetic rats. In present study, we aimed to investigate the protective effects and underlying mechanisms of Nepeta angustifolia on diabetic nephropathy (DN), a microvascular complication. AIM OF THE STUDY: This study is aim to evaluate the protective effect of ethanol extracts of N. angustifolia (NA) on DN, and explore mechanism of action to provide basis for its pharmacological action against DN. MATERIALS AND METHODS: High-fat diet and low-dose streptozotocin administration (HFD/STZ) induced diabetic rats were randomly divided into 5 groups (n = 8): the diabetic model group, metformin group, and three dose groups of NA (60 mg/kg, 120 mg/kg, 240 mg/kg). After administration of NA for 8 weeks, the blood, urine and renal tissue were collected for subsequent experiments. Biochemical markers (urine protein, Cr, BUN), oxidative stress makers (SOD, GSH-px and MDA) and pro-inflammatory mediators (TNF-α, IL-1ß, IL-6 and MCP-1) were evaluated by commercial kit and ELISA, respectively. The effect of NA on DN was further confirmed by evaluation of renal histopathology by using the H&E, PAS and Masson staining. The H2O2-induced HBZY-1 cells (rat glomerular mesangial cells) were also been used to evaluate the renal protective effect of NA (50 µg/mL, 100 µg/mL, 200 µg/mL). The oxidative stress makers were detected by commercial kit. The levels of apoptosis and related proteins (caspase 3, 9) were detected by TUNEL assay and western blot analysis, respectively. The depolarization of mitochondrial membrane potential was detected by JC-1 staining assay. RESULTS: The administration of NA is helpful to maintain near normal body weight, blood glucose, urine volume, urine protein, kidney index and serum levels of Cr and BUN. NA treatment significantly improve renal dysfunction by the down-regulation of renal oxidative stress and pro-inflammatory mediators in HFD/STZ induced diabetic rats. In vitro experiments, NA has a significant cellular protective effect in H2O2-induced HBZY-1 cells, as well as the regulation in increases of SOD level and the decreases of ROS and MDA levels. Furthermore, NA treatment can significantly inhibit H2O2 induced mesangial cells apoptosis by the increasing mitochondrial potential and suppressing caspases-madiated signaling pathway. CONCLUSIONS: NA has obvious improvement on renal dysfunction in HFD/STZ induced diabetic rats. NA can protect mesangial cells by inhibiting oxidative stress induced apoptosis, which may be related to its regulation of mitochondrial-caspase apoptosis pathway.

Nepeta angustifolia attenuates responses to vascular inflammation in high glucose-induced human umbilical vein endothelial cells through heme oxygenase-1 induction.

ETHNOPHARMACOLOGICAL RELEVANCE: The traditional folk medicine Nepeta angustifolia C. Y. Wu (NA) reportedly possesses various biological activities, such as anti-inflammatory, analgesic, antihypoxia, and antifatigue effects. In this study, we evaluated the anti-vascular inflammation effects of N. angustifolia extract in human umbilical vein endothelial cells (HUVECs) induced by high glucose (HG) as well as the underlying mechanisms and verified its activity in diabetic rats. MATERIALS AND METHODS: HUVECs were exposed to 25 mM glucose to induce endothelial dysfunction. Adhesion molecule expression and reactive oxygen species (ROS) were assayed. IκB and IκB phosphorylation, nuclear factor-κB (NF-κB), HO-1 and nuclear factor erythroid 2-related factor 2 (Nrf2) were examined by Western blot. Nuclear localisation of Nrf2 was also examined using immunofluorescence. The in vivo study of NA was tested in diabetic rats in which the thoracic aorta and serum were collected to observe aorta histological change, and evaluate endothelial function and vascular inflammation. RESULTS: The results revealed that HG can significantly promote the generation of ROS, the expression of cell adhesion molecules (CAMs), and the phosphorylation and degradation of IκB and NF-κB activation in HUVECs. These HG-induced phenomena were suppressed by NA-induced heme oxygenase (HO)- 1 expression in a dose- and time-dependent manner by activating Nrf2. The HO-1 inhibitor tin protoporphyrin also dramatically reversed the NA-induced inhibition of CAM expression and the reduction in ROS production. Furthermore, NA also elicited anti-vascular dysfunction effects in diabetic rats, where endothelial function was improved and vascular inflammation was alleviated. CONCLUSION: All these findings indicated that NA attenuated high glucose-induced vascular dysfunction in vitro and in vivo.

Anti-Inflammatory Activity of Epimedium brevicornu Maxim Ethanol Extract.

Epimedium brevicornu Maxim has been used as a traditional herbal drug in China. In this study, the anti-inflammatory effects of E. brevicornu Maxim ethanol extract (EBME) were investigated in RAW264.7 macrophages and mice challenged with lipopolysaccharide (LPS). Results showed that EBME attenuated inflammation by decreasing the production of several proinflammatory mediators, such as nitric oxide (NO), prostaglandin (PG) E2, inducible nitric oxide synthase, and cyclooxygenase-2, in LPS-stimulated RAW264.7 macrophages. EBME increased the expression of heme oxygenase-1 (HO-1) and promoted the nuclear translocation of nuclear factor erythroid 2-related factor 2. The inhibitory effects of EBME on LPS-stimulated NO and PGE2 expression were partially reversed by HO-1 inhibitor. EBME also elicited an anti-inflammatory effect by inhibiting the production of tumor necrosis factor-α, interleukin (IL)-1ß, and IL-6 in LPS-induced peritonitis. Therefore, EBME exhibited anti-inflammatory effects in vitro and in vivo.