Optimization of Extraction and Purification of Polysaccharides from Veronicastrum axillare, and Evaluation of Their Biological Activities.

Veronicastrum axillare polysaccharides (VAP) were isolated by cellulase-assisted digestion. The optimum conditions (2 % cellulase, 47 °C for 2.5 h, then, 95 °C for 2.5 h, pH 4.1, solid/liquid ratio 1 : 7.6) were identified by a combination of single factor optimization and response surface DOE (design of experiment) methods, and achieved a yield of 4.7 %. Treatment with 1 % TCA for 10 min, then, 2 % DEAE-cellulose removed protein and colored impurities. Purified VAP retained most of the radical-scavenging activities and GES-1 cell protection capability in vitro, indicating VAP were the key active components of V. axillare. Some molecular features were identified by FT-IR and NMR analyses. The molecular weight was estimated from DOSY NMR experiments to be around 21 kDa. There were 6.3 % uronic acid residues in the VAP. The constituent sugars after TFA hydrolysis were identified by HPLC to include glucose, arabinose, rhamnose, galactose, and xylose in a molar ratio of 405 : 259 : 82 : 42 : 1.

Veronicastrum axillare Alleviates Ethanol-Induced Injury on Gastric Epithelial Cells via Downregulation of the NF-kB Signaling Pathway.

We used human gastric epithelial cells (GES-1) line in an ethanol-induced cell damage model to study the protective effect of Veronicastrum axillare and its modulation to NF-κB signal pathway. The goal was to probe the molecular mechanism of V. axillare decoction in the prevention of gastric ulcer and therefore provide guidance in the clinical application of V. axillare on treating injuries from chronic nephritis, pleural effusion, gastric ulcer, and other ailments. The effects of V. axillare-loaded serums on cell viability were detected by MTT assays. Enzyme-linked immunosorbent assay (ELISA) and Real-Time PCR methods were used to analyze the protein and mRNA expression of TNF-α, NF-κB, IκBα, and IKKß. The results showed that V. axillare-loaded serum partially reversed the damaging effects of ethanol and NF-κB activator (phorbol-12-myristate-13-acetate: PMA) and increased cell viability. The protein and mRNA expressions of TNF-α, NF-κB, IκBα, and IKKß were significantly upregulated by ethanol and PMA while they were downregulated by V. axillare-loaded serum. In summary, V. axillare-loaded serum has significantly protective effect on GES-1 against ethanol-induced injury. The protective effect was likely linked to downregulation of TNF-α based NF-κB signal pathway.

Veronicastrum axillare Alleviates Lipopolysaccharide-Induced Acute Lung Injury via Suppression of Proinflammatory Mediators and Downregulation of the NF-κB Signaling Pathway.

Veronicastrum axillare is a traditional medical plant in China which is widely used in folk medicine due to its versatile biological activities, especially for its anti-inflammatory effects. However, the detailed mechanism underlying this action is not clear. Here, we studied the protective effects of V. axillare against acute lung injury (ALI), and we further explored the pharmacological mechanisms of this action. We found that pretreatment with V. axillare suppressed the release of proinflammatory cytokines in the serum of ALI mice. Histological analysis of lung tissue demonstrated that V. axillare inhibited LPS-induced lung injury, improved lung morphology, and reduced the activation of nuclear factor-κB (NF-κB) in the lungs. Furthermore, the anti-inflammatory actions of V. axillare were investigated in vitro. We observed that V. axillare suppressed the mRNA expression of interleukin-1ß (IL-1ß), IL-6, monocyte chemotactic protein-1 (MCP-1), cyclooxygenase-2 (COX-2), and tumor necrosis factor-α (TNF-α) in RAW264.7 cells challenged with LPS. Furthermore, pretreatment of V. axillare in vitro reduced the phosphorylation of p65 and IκB-α which is activated by LPS. In conclusion, our data firstly demonstrated that the anti-inflammatory effects of V. axillare against ALI were achieved through downregulation of the NF-κB signaling pathway, thereby reducing the production of inflammatory mediators.

Study on the antiulcer effects of Veronicastrum axillare on gastric ulcer in rats induced by ethanol based on tumor necrosis factor-α (TNF-α) and endothelin-1 (ET-1).

OBJECTIVE: To assess whether Veronicastrum axillare (V. axillare) can ameliorate ethanol-induced gastric mucosal lesions in rats, reduce the production of pro-inflammatory cytokines, suppress apoptosis and improve local microcirculation disturbances. METHODS: Totally 48 male Sprague-Dawley rats were randomly divided into six groups, eight rats in each group. Rats in the normal group and the model group were administered with 0.9% normal saline respectively. Rats in the positive group and ranitidine group were administered with 0.18% ranitidine suspension by intragastric administration respectively. Those in the high dose V. axillare group, the medium dose V. axillare group and the low dose V. axillare group were administrated with V. axillare at the daily dose of 2.8 g/kg, 1.4 g/kg and 0.7 g/kg by intragastric administration. Gastric mucosal lesions were produced by intragastric administration of absolute ethanol. Water extract of V. axillare was successively injected for 14 d and last day was injected 1 h before ethanol administration. Gastric mucosal ulcer index and ulcer inhibitory rate were counted by improved Guth methods. The tissue sections were made for pathological histology analysis. Also, we measured the concentrations of tumor necrosis factor-α (TNF-α) and endothelin-1 (ET-1) in gastric mucosal, as an index of the pro-inflammatory cytokines, apoptosis and local microcirculation. Besides, the mRNA contents of TNF-α and ET-1 were measured to verify effects on gene expression by real-time fluorescent quantitative PCR. RESULTS: Water extract of V. axillare significantly ameliorated the gastric mucosal lesions induced by ethanol administration (P<0.01). Pro-inflammatory cytokines, TNF-α and ET-1 were increased after ethanol administration and significantly reduced by water extract of V. axillare. The expressions of TNF-α and ET-1 mRNA were also be inhibited by water extract of V. axillare. CONCLUSION: Current evidences show water extract of V. axillare is effective for defending against ethanol-induced gastric mucosal lesions, significantly inhibiting the production of pro-inflammatory cytokines and the expressions of TNF-α and ET-1 mRNA, which may be useful for inhibiting apoptosis and improving local microcirculation.

[Antiulcer effects and mechanism study of Veronicastrum axillare on ethanol induced gastric ulcer rats].

OBJECTIVE: To study the antiulcer effects and the mechanism of Veronicastrum axillare (Sieb. et Zucc) Yamazaki (VAY) on ethanol induced gastric ulcer rats. METHODS: Totally 48 healthy SD rats were randomly divided into 6 groups, i.e., the normal group, the model group, the ranitidine group, the high dose VAY group, the medium dose VAY group, and the low dose VAY group, 8 in each group. Rats in the normal group and the model group were administered with normal saline respectively. Rats in the ranitidine group were administered with 0.18% ranitidine suspension (at the daily dose of 0.027 g/kg) by gastrogavage. Those in the high dose VAY group, the medium dose VAY group, and the low dose VAY group were administered with VAY at the daily dose of 2.8 g/kg, 1.4 g/kg, and 0.7 g/kg by gastrogavage, once daily for 14 consecutive days. The gastric ulcer model was established using absolute ethanol after the last gastrogavage. The ulcer index and the ulcer inhibitory rate were compared. The concentrations of malonyldialdehyde (MDA), nitric oxide (NO), epidermal growth factor (EGF), and the activity of superoxide dismutase (SOD) in the serum and the homogenate of the gastric mucosa tissue were detected. RESULTS: Compared with the model group, the gastric ulcer index in the rest groups obviously decreased (P < 0.01). The ulcer index was dose-dependent with VAY (P < 0.01), with the highest gastric ulcer index shown in the high dose VAY group (P < 0.01). Compared with the normal group, the concentrations of MDA and NO significantly increased in the serum and the gastric mucosa tissue, the activity of SOD and the EGF content in the gastric mucosa tissue of rats in the model group significantly decreased (P < 0.01). Compared with the model group, the MDA concentrations in the serum and the gastric mucosa tissue decreased, the serum NO content increased, the NO content in the gastric mucosa tissue decreased, the serum SOD activity increased, the EGF content in the gastric mucosa tissue increased in the rest groups, all showing statistical difference (P < 0.05, P < 0.01). CONCLUSIONS: The water extract of VAY had significant effects on ethanol induced gastric ulcer. Its mechanisms might lie in reducing the generation of free radicals, promoting the oxygen free radical clearance, restraining lipid peroxidation, regulating and controlling the in vivo contents of NO and EGF.