Experimental study of antidiarrheal activity of Salicairine

Antidiarheal activity of catechol and ethyl 5, 8,11,14,17 - icosapentanoate-rich fraction of Annona senegalensis stem bark

Background and aim

Secretory diarrhea is the most common type of diarrhea. This study aimed at exploring the possible mechanism of antisecretory action of Annona senegalensis stem bark and to identify the bioactive compounds.

Experimental procedure

The ability of three crude extract; aqueous, dichloromethane and hexane stem bark extracts to inhibit castor oil-induced stooling in albino rats were assessed. Bioactivity guided fractionation of the most active extract was done using solvent-solvent partitioning (with hexane, dichloromethane, ethylacetate) and column chromatography. In vitro antioxidant activity of the most active sub-fraction was done using standard methods. The most active sub-fraction (25 mg/kg b. wt.) was administered to castor oil-induced diarrheal rats. Diarrheal rats small intestinal malondialdehyde concentration, antioxidant enzyme, cyclooxygenase II and Na+- K+ ATPase activities were determined using standard procedures. GC-MS analysis was done to identify the chemical compounds in the sub-fraction.

Result and conclusion

Aqueous extract significantly decreased the number of wet stools. Sub-fraction 1 of ethylacetate fraction of aqueous stem bark extract (EFAS1) showed the highest stool inhibition. The H2O2 scavenging activity of EFAS1 was significantly greater than ascorbic acid. The sub-fraction significantly increased (p < 0.05) the activity of catalase and Na+- K+ ATPase activities but significantly decreased the concentration of malondialdehyde and cyclooxygenase II activity. GC-MS analysis revealed that EFAS1 is rich in catechol, n-hexadecanoic acid and ethyl-5,8,11,14,17-icosapentanoate. The sub-fraction exerts its antisecretory activity by its antioxidative, inhibition of prostaglandin synthesis and stimulation of Na+- K+ ATPase properties due to the presence of catechol, n-hexedecanoic acid and ethyl-5,8,11,14,17-icosapentanoate.

Evaluation of the anti-diarrheal effects of the whole plant extracts of Cuscuta reflexa Roxb in pigeons

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The antidiarrheal activity of C. reflexa was evaluated in pigeons using the juice, aqueous, and methanol extracts.

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The antidiarrheal effect of C. reflexa was evaluated using different reported research models.

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The juice, aqueous, and methanol extract of C. reflexa exhibit significant anti-motility and anti-secretory potential.

Background

Cuscuta reflexa (dodder) belonging to the family Convolvulaceae has many ethno-medicinal uses such as antidiarrheal and antiemetic. This plant has been employed to treat diarrhea, where the antidiarrheal use of this plant is well established in different communities around the world without scientific bases. In addition, the antibacterial, anthelmintic, anticholinergic, and antihistaminic effects of this parasitic vine are partly responsible for the folkloric antidiarrheal use of this plant. In the present study, the antidiarrheal activity of C. reflexa was evaluated in pigeons (Columba livia) using the juice (JCR), aqueous (CRAE), and methanol (CRME) extracts.

Methods

The antidiarrheal effect of C. reflexa was evaluated using different reported research models, with few modifications. In pigeons, diarrhea was induced by administration of castor oil (6 mL/kg, PO), ampicillin (250 mg/kg, IP), magnesium sulfate (2 gm/kg, PO), and cisplatin (6 mg/kg, IV). In these experiments, loperamide (2 mg/kg, IM) was used as a positive control, whereas JCR (1 mL/kg (1%) and 1 mL/kg (2%), CRAE (50, 100 and 200 mg/kg) and CRME (50, 100 and 200 mg/kg) were administered intramuscularly at different doses into each pigeon in the test groups.

Results

In addition to cisplatin-induced diarrhea, all paradigms tested gave significant results (P < 0.01). The JCR, at different doses, exhibited a significant (p < 0.01) a dose-dependent antidiarrheal effect on both the frequency and the onset of diarrhea. Similarly, CRAE and CRME, at doses of 100 and 200 mg/kg, showed considerable (p < 0.001) inhibition against the onset and frequency of diarrhea. On the other hand, JCR, CRAE, and CRME exerted significant effects (p < 0.001) on the percentage inhibition (PI) of diarrhea and gastrointestinal charcoal transit in a dose-dependent manner. In this respect, the maximum PI (p < 0.01) of JCR, CRAE, and CRME in different experimental paradigms was 43.13, 49.14, and 55.99 %, respectively.

Conclusions

Taken all together, results from this study reveal that the juice, aqueous, and methanol extract of C. reflexa exhibit significant anti-motility and anti-secretory potential. These findings may explain the medicinal use of C. reflexa in folk medicine as an antidiarrheal medicinal plant.

Lythrum salicaria Ellagitannins Stimulate IPEC-J2 Cells Monolayer Formation and Inhibit Enteropathogenic Escherichia coli Growth and Adhesion

Lythrum salicaria herb (LSH) was applied in diarrhea therapy since ancient times. Despite empirically referenced therapeutic effects, the bioactivity mechanisms and chemical constituents responsible for pharmacological activity remain not fully resolved. Taking into consideration the historical use of LSH in treatment of diarrhea in humans and farm animals, the aim of the study was to examine in vitro the influence of LSH and its C-glycosylic ellagitannins on processes associated with maintaining intestinal epithelium integrity and enteropathogenic Escherichia coli (EPEC) growth and adhesion. LSH was not only inhibiting EPEC growth in a concentration dependent manner but also its adhesion to IPEC-J2 intestinal epithelial cell monolayers. Inhibitory activity toward EPEC growth was additionally confirmed ex vivo in distal colon samples of postweaning piglets. LSH and its dominating C-glycosylic ellagitannins, castalagin (1), vescalagin (2), and salicarinins A (3) and B (4) were stimulating IPEC-J2 monolayer formation by enhancing claudin 4 production. Parallelly tested gut microbiota metabolites of LSH ellagitannins, urolithin C (5), urolithin A (6), and its glucuronides (7) were inactive. The activities of LSH and the isolated ellagitannins support its purported antidiarrheal properties and indicate potential mechanisms responsible for its beneficial influence on the intestinal epithelium.

Antidiarrheal activity of 80 % methanol extract of the aerial part of Ajuga remota Benth (Lamiaceae) in mice

Background

In the Ethiopian traditional medicine, the aerial part of Ajuga remota Benth is used in the treatment of diarrhea. There are different mechanisms by which Ajuga remota may have antidiarrheal effect. Some of the possible mechanisms are through its anthelmintic and antibacterial activity. The present study aimed to evaluate whether the antidiarrheal effect of the plant also include antimotility and antisecretory effect using 80 % methanol extract of A. remota (MEAR).

Methods

The MEAR was administered at doses of 200, 400, 600 and 800 mg/kg to four groups of mice (six animals per group) orally in castor oil diarrhea model. The effect of the extract on enteropooling and gastrointestinal transit model was also evaluated using the same grouping and dosing. Two other groups, one as control and the other as standard (loperamide 5 mg/kg) were used for comparison with the treatment groups.

Results

The extract at the doses of 400, 600, and 800 mg/kg produced a dose-dependent and significant inhibition both on the frequency and onset of diarrhea. The percentage purging frequency was 53.4, 66.7, 79.6, and 66.7 % (p < 0.001) at three doses of MEAR (400, 600, and 800 mg/kg) and with loperamide (5 mg/kg), respectively. The percentage inhibition in intestinal fluid accumulation was 42.5, 62.1, and 74.2 % (p < 0.001) at the doses of 400, 600 and 800 mg/kg of MEAR, respectively. The MEAR also inhibited the intestinal transit of charcoal meal in a dose dependent manner both in the normal and castor oil induced intestinal transit.

Conclusion

This study has shown that the 80 % methanol extract of A. remota contains pharmacologically active substances with significant antimotility and antisecretory effect contributing for its antidiarrheal activity.

Lythrum salicaria L.-Underestimated medicinal plant from European traditional medicine. A review

ETHNOPHARMACOLOGICAL RELEVANCE

Purple loosestrife-Lythrum salicaria L. is a herbaceous perennial plant belonging to the Lythraceae family. It has been used for centuries in European traditional medicine. Despite Lythri herba being a pharmacopoeial plant material (Ph. Eur.), L. salicaria popularity as a medicinal plant has recently declined. The aim of the paper is to recall a traditional and historical use of L. salicaria and juxtapose it with comprehensive view on the current knowledge about its chemical composition and documented biological activities in order to bring back the interest into this valuable plant and indicate reasonable directions of future research and possible applications.

MATERIALS AND METHODS

Systematic survey of historical and ethnopharmacological literature was carried out using sources of European and American libraries. Pharmacological and phytochemical literature research was performed using Scopus, PubMed, Web of Science and Reaxys databases.

RESULTS

The review of historical sources from ancient times till 20th century revealed an outstanding position of L. salicaria in traditional medicine. The main applications indicated were gastrointestinal tract ailments (mainly dysentery and diarrhea) as well as different skin and mucosa affections. The current phytochemical studies have shown that polyphenols (C-glucosidic ellagitannins and C-glucosidic flavonoids) as well as heteropolysaccharides are dominating constituents, which probably determine the observed pharmacological effects. The extracts and some isolated compounds were shown to possess antidiarrheal, antimicrobial, anti-oxidant, anti-inflammatory and anti-diabetic activities.

CONCLUSIONS

The intrinsic literature overview conclusively demonstrates that L. salicaria L. used to be considered as an exceptionally effective remedy in European traditional medicine. Despite its unquestionable important position from unknown reasons its popularity has been weakened during the past few decades. Unfortunately the contemporary pharmacological research is still insufficient to support its thoroughly described traditional uses. The necessity of complex studies regarding modes of action, which would directly refer to L. salicaria main traditional applications-gastrointestinal tract ailments, is strongly underlined.

Phytochemical Evaluation of Lythrum Salicaria Extracts and Their Effects on Guinea-Pig Ileum

n-Hexane, chloroform, ethyl acetate and 50% ethanol in water extracts prepared from the air-dried flowering parts of Lythrum salicaria L. were tested for in vitro pharmacological properties on Guinea-pig ileum, which is suitable for detecting a whole range of neuronal and smooth muscle effects. UHPLC-MS was used to evaluate polyphenol components of the extracts. In the ileum, the most prominent response (46.4% related to 0.5 μM histamine) of the extracts causing smooth muscle contractions were triggered by the 50% ethanol in water extract in a concentration-dependent manner. Atropine, indomethacin and PPADS plus suramin significantly reduced the contractile response caused by this extract. The strongest inhibition was due to atropine. The results suggest that L. salicaria extracts have a moderate muscarinic receptor agonist effect in Guinea-pig ileum and that prostanoids and purinoceptor mechanisms are involved to some extent. Therefore diluted extracts of L. salicaria p.o. could be used as a mild stimulant of gastrointestinal motility. The 50% ethanol in water extract was rich in polyphenols. n-Hexane, chloroform and ethyl acetate extracts failed to contain catechin, caffeic acid, quercetin-3-D-galactoside and rutin, but they all showed spasmogenic effects, and, therefore we do not think that these compounds could be involved in the spasmogenic activity.

Variability of Total Flavonoid, Polyphenol and Tannin Contents in Some Lythrum salicaria Populations

Lythrum salicaria L. can vary in some morphological and phytochemical features according to its habitat. The present study investigates and compares the total flavonoid, polyphenol and tannin composition of twelve populations of L. salicaria collected from different ecological habitats in south-west Hungary. We studied the plant heights and soil moistures of the habitats analyzing the potential correlation between the morphological and environmental factors and chemical compositions. Total flavonoid, polyphenol and tannin contents were determined according to the valid spectroscopic methods of the European Pharmacopoeia. Total flavonoid content was higher in the populations collected during the main blooming period in August than at the beginning of flowering in July. Higher values for total polyphenol and tannin were detected in flowering branch tips in August than in July, and higher ones in leaves and shoots in July than in August. The highest flavonoid content was measured in the leaves, followed by the flowering branches and shoots as opposed to the total polyphenol and tannin contents, which were higher in the flowering branch tips than in the other organs.