Antidiarrheal Effect of 80% Methanol Extract and Fractions of the Leaves of Ocimum lamiifolium in Swiss Albino Mice

Review of Medicinal Plants Traditionally Used to Treat Diarrhea by the People in the Amhara Region of Ethiopia

Background

Diarrheal illness is the second-most common cause of death in under-five children. Worldwide, it results in about 1.7 billion illnesses and 525,000 deaths among under-five children annually. It is the leading cause of malnutrition among under-five children. Different people use medicinal plants to treat diarrhea. The present study aimed to review the medicinal plants used to treat diarrhea by the people in the Amhara region and to diagnose whether the antidiarrheal activities of the medicinal plants have been confirmed by studies using animal models.

Methods

The author searched 21 articles from worldwide databases up to December 2022 using Boolean operators ("AND" and "OR") and the terms "ethnobotanical studies," "ethnobiology," "traditional medicine," "ethnobotanical knowledge," and "Amhara region."

Results

From the 21 studies reviewed, 50 plant species grouped into 28 families were reported to treat diarrhea by the people in the Amhara region. The top most used families were Lamiaceae (12%), Fabaceae (8%), Asteraceae, Cucurbitaceae, Euphorbiaceae, and Poaceae (6% each). The modes of administration of the plant parts were orally 98.88% and topically 1.12%. The different extracts of 18 (or 36%) of the medicinal plants traditionally used to treat diarrhea by the people in the Amhara region have been proven experimentally in animal models.

Conclusions

The people in the Amhara region use different medicinal plants to treat diarrhea. Most of them take the medicinal plants orally. The traditional claim that 60% of medicinal plants are antidiarrheal has been confirmed in in vitro studies.

Antidiarrheal and antioxidant activities of Ajuga iva (L.) leave extract

We studied the effect of Ajuga iva leaves extract (AIE) on the intestinal absorption, motricity and its antioxidant capacity against diarrhea. Wistar rats were divided and received either: castor oil (CO), CO and loperamide or CO and different doses of AIE. AIE prevented dose-dependently CO-induced diarrhea. AIE at 800 mg/kg showed inhibition efficiency on defecation and diarrhea. The pro-oxidant effect of the CO in the small intestine was inhibited significantly in presence of AIE: increasing glutathione peroxidase (GPx) activity and lowering oxygen free radicals (OH°, O2°-), carbonyl protein and malondialdehyde (MDA) levels. However, co-administration of AIE in castor oil-exposed groups significantly increased the intestinal contents of calcium and magnesium. AIE exhibits significant anti-diarrheal activity, related in part to its antioxidant properties. Our investigation also provides experimental evidence for the traditional use of this medicinal plant in the treatment of diarrhea.

Deep-fried Atractylodes lancea rhizome alleviates spleen deficiency diarrhea-induced short-chain fatty acid metabolic disorder in mice by remodeling the intestinal flora

ETHNOPHARMACOLOGICAL RELEVANCE

Atractylodes lancea (Thunb.) DC. is a Chinese herb that has been commonly used to treat spleen-deficiency diarrhea (SDD) in China for over a thousand years. However, the underlying mechanism of its antidiarrheal activity is not fully understood.

AIM OF THE STUDY

The antidiarrheal effects of the ethanol extract of deep-fried A. lancea rhizome (EEDAR) due to spleen deficiency induced by folium sennae (SE) were determined on the regulation of the short-chain fatty acid (SCFA) metabonomics induced by the intestinal flora.

MATERIALS AND METHODS

The effects of EEDAR on a SE-induced mouse model of SDD were evaluated by monitoring the animal weight, fecal water content, diarrhea-grade rating, goblet cell loss, and pathological changes in the colon. The expression of inflammatory factors (tumor necrosis factor [TNF]-α, interleukin [IL]-1β, IL-6, IL-10), aquaporins (AQP3, AQP4, and AQP8), and tight junction markers (ZO-1, occludin, claudin-1) in colon tissues were determined using quantitative polymerase chain reaction and western blotting. SCFA metabonomics in the feces of mice treated with EEDAR was evaluated using gas chromatography-mass spectrometry. Furthermore, 16S rDNA sequencing was used to determine the effect of EEDAR on the intestinal flora of SDD mice, and fecal microbiota transplantation (FMT) was used to confirm whether the intestinal flora was essential for the anti-SDD effect of EEDAR.

RESULTS

Treatment with EEDAR significantly improved the symptoms of mice with SDD by inhibiting the loss of colonic cup cells, alleviating colitis, and promoting the expression of AQPs and tight junction markers. More importantly, the effect of EEDAR on the increase of SCFA content in mice with SDD was closely related to the gut microbiota composition. EEDAR intervention did not significantly improve intestinal inflammation or the barrier of germ-free SDD mice, but FMT was effective.

CONCLUSION

EEDAR alleviated SE-induced SDD in mice, as well as the induced SCFA disorder by regulating the imbalance of the intestinal microbiota.

Sub-chronic toxicity of the aqueous leaf extract of Ocimum lamiifolium Hochst. ex Benth on biochemical parameters and histopathology of liver and kidney in rats: in vivo and in- silico toxicity studies

BACKGROUND

The aerial part of Ocimum lamiifolium is commonly used in Ethiopian traditional medicine. Although this plant is mostly used in traditional medicine, its safety profile has not been documented yet. The aim of this study was to assess the sub-chronic toxicity of O. lamiifolium aqueous extract in rats and to determine the toxicity profile of GC-MS identified bioactive compounds obtained from essential oil of O. lamiifolium using in silico toxicity methods.

METHODS

Eighty rats (40 male and 40 female) were randomly assigned to four groups of ten rats per sex/group. For 90 days, Groups I-III received 200, 400, and 600 mg/kg bw of aqueous extract of O. lamiifolium, respectively. Distilled water was given to Group IV (control). Clinical observations, food intake, and rat weight were all recorded during the experiment. In addition, several biochemical parameters, organ weight, and histology of the liver and kidney were all evaluated. For the in-silico toxicity study, GC-MS identified bioactive compounds in O. lamiifolium essential oil were obtained from published articles. The compounds two-dimensional structures were constructed using Chemdraw. The two-dimensional structures were converted into a simplified molecular input line entry system (SMILES) using the Swiss ADMET web tool. Furthermore, the toxicity parameters were predicted using the ProTox II server.

RESULTS

The administration of an aqueous extract of O. lamiifolium leaves significantly (p < 0.05) reduced the test animals' food intake and body weight gain. In the high dose (600 mg/kg bw) treated group, the serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase levels were significantly increased (p < 0.05). In female rats given 600 mg/kg bw of O. lamiifolium, the levels of serum urea were also increased. In addition, rats given 600 mg/kg bw had significantly lower blood glucose levels than the control group (p < 0.05). Doses up to 400 mg/kg bw didn't bring a significant change to the histology of the liver. However, in the high dose (600 mg/kg bw) treated group, some female rats' livers showed mild sinusoidal and central vein dilatation, as well as parenchymal necrosis. our findings showed that all compounds derived from the essential oil of O. lamiifolium showed no mutagenicity or cytotoxicity. However, 30% of the compounds tested were hepatotoxic, 20% carcinogenic, and 20% immunotoxin.

CONCLUSION

Our findings showed that oral administration of O. lamiifoliums aqueous extract up to a dose of 400 mg/kg bw is not toxic. However, high-dose (600 mg/kg bw) significantly affected the food consumption and weight gain of the experimental rats and the serum concentration of some liver and kidney enzymes were also significantly increased. Additionally, a considerable proportion of the tested compounds were predicted to be hepatotoxic, carcinogenic and immunotoxin. Furthermore, before employing O. lamiifolium preparations as drugs, a chronic toxicity research on the essential oil as well as its components that exhibited toxicity in the in-silico toxicity study is needed. Finally, use high doses of O. lamiifolium leaves with caution.