HEF-19-induced relaxation of colonic smooth muscles and the underlying mechanisms

Protective effect of valerian extract capsule (VEC) on ethanol- and indomethacin-induced gastric mucosa injury and ameliorative effect of VEC on gastrointestinal motility disorder

CONTEXT

Valerian extract capsule (VEC) is an effective Chinese patent medicine used for gastrointestinal (GI) diseases.

OBJECTIVE

To investigate the detailed pharmacological activity for VEC clinical effects in GI diseases.

MATERIALS AND METHODS

Sprague-Dawley rats were divided into six groups: control, model, and drug-treated (VEC-L, VEC-M, VEC-H, and teprenone). Rats were orally administered VEC (124, 248, 496 mg/kg) and teprenone (21.43 mg/kg) for 3 consecutive days. After 1 h, the five groups (except the control group) were orally given ethanol (10 mL/kg) for 1 h or indomethacin (80 mg/kg) for 7 h. The spasmolytic activity of VEC (0.01-1 mg/mL) on ACh/BaCl₂-induced New Zealand rabbit smooth muscle contraction was performed. The C57BL/6 mice carbon propelling test evaluated the effects of VEC (248-992 mg/kg) on intestinal motility in normal and neostigmine/adrenaline-induced mice.

RESULTS

Compared with the model group, VEC treatment reduced the gastric lesion index and mucosal damage. Further experiments showed that the pathological ameliorative effect of VEC was accompanied by augmentation of the enzymatic antioxidant system and cytoprotective marker (COX-1, p < 0.01; PGI2 p < 0.05;), along with the alleviation of the levels of MPO (ethanol: 15.56 ± 0.82 vs. 12.15 ± 2.60, p < 0.01; indomethacin: 9.65 ± 3.06 vs. 6.36 ± 2.43, p < 0.05), MDA (ethanol: 1.66 ± 0.44 vs. 0.81 ± 0.58, p < 0.01; indomethacin: 1.71 ± 0.87 vs. 1.09 ± 0.43, p < 0.05), and inflammatory mediators. VEC decreased the high tone induced by ACh/BaCl₂ and promoted intestinal transit in normal and neostigmine/adrenaline-induced mice.

DISCUSSION AND CONCLUSIONS

VEC showed a potential gastroprotective effect, suggesting that VEC is a promising phytomedicine for the treatment of GI diseases.

Ethanol Extract of Glycyrrhiza uralensis Fisch: Antidiarrheal Activity in Mice and Contraction Effect in Isolated Rabbit Jejunum

OBJECTIVE

To evaluate the antidiarrheal effect of ethanol extract of Glycyrrhiza uralensis Fisch root (GFR) in vivo and jejunal contraction in vitro.

METHODS

In vivo, 50 mice were divided into negative control, positive control (verapamil), low-, medium- and high-dose GFR (250, 500, 1,000 mg/kg) groups by a random number table, 10 mice in each group. The antidiarrheal activity was evaluated in castor oil-induced diarrhea mice model by evacuation index (EI). In vitro, the effects of GFR (0.01, 0.03, 0.1, 0.3, 1, 3, and 10 g/L) on the spontaneous contraction of isolated smooth muscle of rabbit jejunum and contraction of pretreated by Acetylcholine (ACh, 10 µmol/L) and KCl (60 mmol/L) were observed for 200 s. In addition, CaCl₂ was accumulated to further study its mechanism after pretreating jejunal smooth muscle with GFR (1 and 3 g/L) or verapamil (0.03 and 0.1 µmol/L) in a Ca²⁺-free-high-K⁺ solution containing ethylene diamine tetraacetic acid (EDTA).

RESULTS

GFR (500 and 1,000 mg/kg) significantly reduced EI in castor oil-induced diarrhea model mice (P<0.01). Meanwhile, GFR (0.01, 0.03, 0.1, 0.3, 1, 3, and 10 g/L) inhibited the spontaneous contraction of rabbit jejunum (P<0.05 or P<0.01). Contraction of jejunums samples pretreated by ACh and KCl with 50% effective concentration (EC₅₀) values was 1.05 (0.71-1.24), 0.34 (0.29-0.41) and 0.15 (0.11-0.20) g/L, respectively. In addition, GFR moved the concentration-effect curve of CaCl₂ down to the right, showing a similar effect to verapamil.

CONCLUSIONS

GFR can effectively against diarrhea and inhibit intestinal contraction, and these antidiarrheal effects may be based on blocking L-type Ca²⁺ channels and muscarinic receptors.

Anwulignan Ameliorates the Intestinal Ischemia/Reperfusion

Anwulignan is one of the monomer compounds in the lignans from Schisandra sphenanthera In this study, we observed the effect of anwulignan on intestinal ischemia/reperfusion (II/R) injury in male Sprague-Dawley rats and explored the underlying mechanisms. The results showed that pretreatment with oral anwulignan could significantly increase the mesenteric blood microcirculatory flow velocity; relieve the congestion and pathologic injury of jejunum; enhance the autonomic tension of jejunum smooth muscle and its reactivity to acetylcholine; increase the activities of superoxide dismutase, catalase, glutathione S-transferase, and choline acetyltransferase; increase the contents of acetylcholine and glutathione in the serum or jejunal tissue; decrease the activities of myeloperoxidase, protein kinase C, and nicotinamide adenine dinucleotide phosphate oxidase; reduce the contents of malondialdehyde, 8-hydroxy-2-deoxyguanosine, nicotinamide adenine, reactive oxygen species, tumor necrosis factor-α, interleukin (IL)-6, and IL-1β; increase the expression levels of muscarinic receptor 3, PI3K, phosphorylation protein kinase B, p-GSK3β Ser9, Nrf2, p-Nrf2, heme oxygenase (decycling) 1, and b-cell lymphoma 2 in the jejunal tissue; and decrease the expression levels of p-GSK3β Tyr216, kelch-like ECH-associated protein 1, Bax, and cleaved caspase-3, suggesting that anwulignan can ameliorate II/R-induced jejunal tissue injury in rats and that the mechanism may be related to its activating the PI3K/protein kinase B pathway and then regulating the Nrf2/Anti-oxidative Response Element signaling pathway and the expression of apoptosis-related proteins to play antioxidant and antiapoptotic roles. SIGNIFICANCE STATEMENT: Anwulignan can significantly reduce jejunal tissue injury and the production of inflammatory factors in rats with intestinal ischemia-reperfusion injury, improve the antioxidant capacity, and reduce the apoptosis of jejunal tissue, and it has the effect of significantly improving intestinal ischemia-reperfusion injury in rats, suggesting that anwulignan may be used as a potential drug for the prevention and treatment of intestinal ischemia-reperfusion injury or a resource for the development of health food.