The rhizomes of Atractylodes macrocephala relieve loperamide-induced constipation in rats by regulation of tryptophan metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Constipation is one of the most prevalent gastrointestinal tract diseases that seriously affects health-related quality of human life and requires effective treatments without side effect. The rhizome of Atractylodes macrocephala Koidz. (Compositae), called Atractylodes Macrocephala Rhizome (AMR), a commonly used traditional Chinese medicine, has been used to relieve the clinical symptoms of patients with constipation.

AIM OF THE STUDY

To reveal the dose-dependent laxative effect and potential mechanism of AMR on loperamide-induced slow transit constipation (STC) rats.

MATERIALS AND METHODS

Loperamide-induced constipation rat model was established and the dose-dependent laxative effect of AMR was investigated. Untargeted metabolomics based on an UPLC-Q/TOF-MS technique combined with western blot analysis was used to explain the potential mechanism of AMR relieve loperamide-induced constipation in rats.

RESULTS

The results showed that medium dose of AMR (AMR-M, 4.32 g raw herb/kg) and high dose of AMR (AMR-H, 8.64 g raw herb/kg) treatments significantly increased the fecal water content, Bristol score, gastrointestinal transit rate, and recovered the damaged colon tissues of constipated rats, but low dose of AMR (AMR-L, 2.16 g raw herb/kg) did not show laxative effect. Both AMR-M and AMR-H treatments also remarkably reduced the serum levels of vasoactive intestinal peptide (VIP), somatostatin (SS) and dopamine (DA), and increased the levels of motilin (MTL), gastrin (GAS) and 5-hydroxytryptamine (5-HT). Urine metabolomics revealed that constipation development was mainly ascribed to the perturbed tryptophan metabolism, and AMR-M and AMR-H markedly corrected the abnormal levels of five urine tryptophan metabolites, namely 4,6-dihydroxyquinoline, indole, 4,8-dihydroxyquinoline, 5-hydroxytryptamine, and kynurenic acid. Additionally, western blot analysis confirmed that the abnormal expression of rate-limiting enzyme involving in tryptophan metabolism, including tryptophan hydroxylase (TPH), monoamine oxidase (MAO) and indoleamine-2,3-dioxygenase (IDO) in the colon of constipated rats, were mediated by AMR-M and AMR-H.

CONCLUSIONS

The findings provide insight into the mechanisms of STC and AMR could be developed as new therapeutic agent for prevention or healing of constipation.

Exploration of the profile-effect relationship of Siraitia grosvenorii aqueous extracts related to their laxative effect on the basis of gray correlation analysis

BACKGROUND

Siraitia grosvenorii (binomial name Siraitia grosvenorii (Swingle) C. Jeffrey ex Lu et Z. Y. Zhang), also called Arhat Fruit or Monk's Fruit, is a dried ripe fruit belonging to the Cucurbitaceae Family. S. grosvenorii has a long history of being used for constipation treatment in folk medicine. However, there are few studies where the laxative effect, related mechanisms, and active constituents of S. grosvenorii were investigated. This research explores the relationship between the common components and the laxative effect of aqueous extracts of S. grosvenorii from different habitats in China.

METHODS

The fingerprints of S. grosvenorii aqueous extracts from different habitats were established by HPLC. The constipation mice model was used to investigate the laxative effect of S. grosvenorii aqueous extracts. The motilin (MTL) level in mice serum, and the water content of the large and small intestines in mice were determined. The profile-effect relationship of S. grosvenorii aqueous extracts was preliminarily clarified using gray correlation analysis.

RESULTS

Nine common peaks were identified from the fingerprint of aqueous extracts of S. grosvenorii. The aqueous extracts obviously shortened the incubation period of defecation, and significantly increased the number of defecations, and the wet and dry weight of defecation in constipated mice. The profile-effect relationship indicated that seven common peaks were highly correlated with the effect of the incubation period of defecation, the number of defecations, and the wet and dry weight of defecation in mice.

CONCLUSION

This work provides a promising method for the fingerprint establishment, pharmacodynamic evaluation, and quality control of S. grosvenorii on the basis of its profile-effect relationship.

Cactus cladodes cause intestinal damage, but improve sheep performance

The objective of this study was to evaluate the effect of three varieties of cactus cladodes resistant to carmine cochineal on the animal performance and histology of the large intestine of sheep. Forty lambs (21.0 ± 2.0 kg body weight) were distributed in a completely randomized design, with four treatments and ten repetitions. The experimental treatments consisted of a control diet and three more diets in which part (750 g/kg) of the elephant grass hay, and all the corn were replaced by Miúda cactus cladodes, IPA-Sertânia cactus cladodes, or Orelha de Elefante Mexicana (O.E.M.) cactus cladodes. On the 60th day after the introduction of the tested diets, blood samples were collected to quantify serum magnesium (Mg²⁺) levels. After 63 days of experiment, the animals were slaughtered and fragments of the cecum and colon were collected for histopathological analysis. The inclusion of the Miúda and O.E.M. cactus cladodes in the diet caused inflammatory lesions in the cecum (100% of the animals) and in the colon (71.43% of the animals) of the sheep. The inflammation in the cecum caused by Miúda and O.E.M. cactus cladodes was considered accentuated (P = 0.009). Less voluntary water intake was observed for animals submitted to diets with cactus cladodes (P < 0.001), as well as higher water content in the feces (P < 0.001). The cactus cladodes, especially the Miúda and O.E.M. varieties, cause lesions in the tissue morphology of the cecum and colon of sheep, but improve productive performance.

Morning glory seed keeps laxative effect while retains less subchronic toxicity after being fried

ETHNOPHARMACOLOGICAL RELEVANCE

Morning glory seed (MGS), has been widely used in treating constipation especially towards children. Clinically, people usually take fried MGS (MGSF) in formulas to reduce its side effect. However, the safety of MGSF other than MGS has yet to be explored.

OBJECTIVE

The study aimed to reveal the potential mechanisms of using MGSF instead of MGS basing on chemistry, pharmacodynamics and toxicology.

METHODS

The chemical compositions of the extracts of MGS and MGSF were compared using UPLC-Q-TOF/MS method. Simultaneously, to prove the availability and safety of MGSF, we investigated the laxative effect and subchronic toxicity of MGS and MGSF and addressed the mechanism of laxative effect of them.

RESULTS

In this study, less phenolic acids and more fatty acids were detected in MGSF compared with the compounds in MGS. Moreover, we found that MGS group had stronger laxative effect than MGSF group via downregulating the expression of AQP3 protein. As for subchronic toxicity test, the body weights of MGS group were lower than MGSF group. In serum biochemistry and histopathological examinations, MGS group could cause more serious toxicity in liver, kidney and colon than MGSF group with higher values of BUN, Cr, AST and ALP.

CONCLUSION

Based on the findings in this study, MGSF with varied compounds contents could still keep the laxative effect while retain less subchronic toxicity, which emphasized the necessity of processing and provided an insight into the rational use of MGSF in clinical practice.