Effect of Aframomum melegueta. Seed Extract on Castor Oil–Induced Diarrhea

ABSTRACT

The effect of the aqueous (aq) seed extract of Aframomum melegueta. K. Schum. (Zingiberaceae) on castor oil-induced diarrhea, intestinal fluid secretion, and gastrointestinal transit was investigated in the study. Castor oil (10 ml/kg, p.o.) induced copious diarrhea in all rats 3 h after treatment. Furthermore, it produced a significant increase in the volume of intestinal fluid secretion in rats and also enhanced intestinal transit in mice. The aq seed extract of A. melegueta. (100–500 mg/kg, p.o.) offered significant protection against diarrhea induced by the oil. At a dose range of 250–500 mg/kg, the extract reduced significantly the volume of fluid secretion in castor oil–treated rats. At these doses, it also demonstrated a significant antitransit activity in a dose-related manner. Acetylsalicylic acid (100 mg/kg, p.o.) delayed diarrhea and reduced the number of animals with diarrheal droppings to 20%. At the same dose level, acetylsalicylic acid reduced significantly the volume of intestinal fluid secretion but lacked antitransit property in castor oil–treated animals. N.-Nitro-L-arginine methyl ester (L-NAME) (2.5–10 mg/kg, i.p.) dose-dependently reduced the number of animals with diarrhea. At 50 mg/kg i.p., it offered 100% protection against diarrhea induced by the oil. Furthermore, L-NAME (10 mg/kg, i.p.) significantly inhibited both the intestinal fluid secretion and gastrointestinal transit induced by castor oil. However, L-NAME (10 mg/kg, i.p.) did not significantly modify the antidiarrheal effect of A. melegueta.. L-Arginine, a substrate of nitric oxide synthase or isosorbide dinitrate, a nitric oxide donor, did not alter the effect of A. melegueta. on diarrhea. Ascorbic acid (100 mg/kg, p.o.) and α.-tocopherol (20 mg/kg, p.o.) reduced the number of animals with diarrhea to 80% and 70%, respectively. However, they both lacked significant activities on intestinal fluid secretion and gastrointestinal transit induced by castor oil. The combination of ascorbic acid (100 mg/kg, p.o.) or α.-tocopherol (20 mg/kg, p.o.) with A. melegueta. (500 mg/kg) offered higher protection against diarrhea than the extract alone. Considering these results together, it may be inferred that Aframomum melegueta. seed extract may be a useful antidiarrheal agent.     

Antidiarrheal Activity of the Fruits of Vitex doniana. in Laboratory Animals

Abstract

The effect of different doses of the aqueous extract of Vitex doniana. Sweet (Verbenaceae) on acetylcholine and histamine-induced contractions on isolated guinea pig ileum was evaluated. The effect of the extract on intestinal peristalsis and castor oil–induced diarrhea in mice was also studied. The results showed that the extract possess a concentration-dependent inhibition of both acetylcholine and histamine-induced contractions. The extract (at doses of 150–650 mg/kg) also inhibited gastric peristalsis in mice fed charcoal meal and significantly protected mice against castor oil–induced diarrhea. Phytochemical screening of the extract revealed the presence of anthraquinones, flavonoids, saponins, sterols, and tannins. The findings in this study indicate that the aqueous extract of V. doniana. fruits may contain some pharmacologically active components that perhaps will be useful as antidiarrheal agents. The findings have also validated the use of this plant in traditional cure of diarrhea.     

Antidiarrheal evaluation of the ethanol extract of Nauclea latifolia root bark

Nauclea latifolia (Rubiaceae) is a medicinal plant used in Nigeria folk medicine for the treatment of gastrointestinal disorders. The root bark of the plant was extracted with 70% ethanol and the extract screened for antidiarrheal activity by investigating castor oil-induced diarrhea and small intestinal motility in mice. The effects of the extract on isolated rat ileum were also investigated. The extract (125, 250 and 500 mg/kg) caused a significant decrease in the frequency of diarrhea and conferred protection following castor oil administration (P < 0.05). It also significantly (P < 0.0001) inhibited small intestinal motility in mice at the same doses. Its activity was dose-dependent and when compared to atropine, its antidiarrheal effects at 500 mg/kg were 179% and 165% respectively, in castor oil-induced diarrhea and small intestinal motility experiments. Extract effects on rat ileum revealed a significant (P < 0.0001) inhibition of acetylcholine-induced contractions at 0.2 and 2 mg/mL final bath concentrations used. These findings confirm the antidiarrheal activity of the root bark extract of N. latifolia.     

Evaluation of Antidiarrheal Potential of Emblica officinalis.

ABSTRACT

The antidiarrheal potential of the methanol extract of the fruit of Emblica officinalis. Gaertn. Euphorbiaceae was evaluated using several experimental models of diarrhea in Wistar albino rats. The methanol extract showed a significant inhibitory effect on rats with diarrhea induced by castor oil and magnesium sulfate. The methanol extract produced a significant reduction in gastrointestinal motility in charcoal meal tests in rats. It also significantly inhibited PGE₂-induced enteropooling as compared to control animals. The results obtained establish the efficacy and substantiate the use of this herbal remedy as a nonspecific treatment for diarrhea in folk medicine.     

Role of the Rosa canina L. leaf extract as an antidiarrheal drug in rodents

Objectives:

The objective of the study was to investigate the effect of the leaf extract of Rosa canina L. against experimental diarrhea induced by castor oil in rodents.

Materials and Methods:

The methanol extract of Rosa canina L. (30 and 60 mg/kg body weight) was administered orally to two groups of mice (five animals per group) in order to evaluate the activity of the extract against the castor oil-induced diarrhea model in mice. Two other groups received normal saline and diphenoxylate (5 mg/kg) as positive control. The effect of the extract on intestinal transit and castor oil-induced intestinal fluid accumulation (enteropooling) was assessed. The effects of the extract on the isolated rabbit jejunum and on the isolated rat ileum were studied.

Results:

The preliminary phytochemical screening of the leaf extract of Rosa Canina L. revealed the presence of alkaloids, flavonoids, glycosides, saponins, and volatile oil. Intraperitoneal LD50 of the extract was found to be 455.19 ± 23 mg/kg in mice. The antidiarrheal effect of the methanolic extract exhibited a concentration-dependent inhibition of the spontaneous pendular movement of the isolated rabbit jejunum and inhibited acetylcholine-induced contraction of the rat ileum. A dose-dependent decrease in gastrointestinal transit was observed with extracts (30 and 60 mg/kg), which also protected mice against castor oil-induced diarrhea and castor oil-induced fluid accumulation, respectively.

Conclusions:

The presence of some of the phytochemicals in the leaf extract may be responsible for the observed effects, and also the basis for its use in traditional medicine as an antidiarrheal drug.     

Anti-inflammatory Properties of Amaranthus spinosus Leaf Extract

The methanol extract of Amaranthus spinosus L. leaves was evaluated for anti-inflammatory activities in different animal models. The effect of the plant extract was also studied on castor oil–induced diarrhea and gastric mucosal integrity. The extract (25–100 mg/kg) inhibited the carrageenan-induced rat paw edema and produced significant (p < 0.05) inhibition of acetic acid–induced increased vascular permeability. Inhibition of the cotton pellet granuloma was also inhibited by 100 mg/kg of the plant extract. Analgesic activity was exhibited with the significant and dose-related reduction in the number of writhings induced with acetic acid, as well reduction in paw licking induced by injection of formalin in mice. The extract (50 and 100 mg/kg) produced gastric erosion in rats, following repeated administration for 4 days, and with 25–100 mg/kg of the extract, there was a statistically significant (p < 0.05) reduction in castor oil–induced diarrhea in rats. These results demonstrate the anti-inflammatory properties of the leaf extract of A. spinosus. It is also suggested that the plant extract probably acts by the inhibition of prostaglandin biosynthesis.     

Evaluation of the anti-diarrheal activity of Salvia connivens

Context: Diarrheal disease is a leading cause of mortality and morbidity and accounts for 5–8 million deaths worldwide each year. Salvia connivens Epling (Lamiaceae) is used to treat sore throat, fevers, diarrhea, malaria, and also is used as an antipyretic.

Objective: The present study evaluates the efficacy of S. connivens in the treatment of diarrhea using animal models.

Materials and methods: The anti-diarrheal effect of methanol extract of S. connivens was investigated on mice with castor oil, arachidonic acid (AA) or prostaglandin E₂ (PGE₂)-induced diarrhea. On Wistar rats, the activity was evaluated on the intestinal transit and Castor oil-induced enteropooling.

Results: The methanol extract at doses of 6.25, 12.5, 25, 50, 100, and 200?mg/kg on castor oil-induced diarrhea reduced the diarrhea by 32.3, 41.9, 67.7, 74.2, 83.3, and 100%, respectively. Additionally, this extract, at doses of 200?mg/kg, inhibited AA-induced diarrhea by 100%. The methanol extract produced no effect on PGE₂-induced diarrhea at the same doses. In Wistar rats, at dose of 200?mg/kg, the methanol extract inhibited intestinal transit and decreased the volume of intestinal secretion induced by castor oil.

Discussion: The methanol extract showed anti-diarrheal effect on the animal models used. Phytochemical screening revealed the presence of alkaloids, tannins, and saponins which may be responsible for this effect. The extract did not cause any mortality or any visible signs of toxicity or differences in food and water uptake were seen.

Conclusions: These results justify the use of S. connivens as an anti-diarrheal agent.     

左金丸对胃肠道的调节作用

目的 研究左金丸在胃肠道调节方面的作用。方法 通过ig给予0.1%甲基橙溶液,计算其胃残留率,观察左金丸对小鼠胃排空的影响;通过ig 5%的炭末,计算炭末推进率,观察左金丸对正常小鼠小肠运动的影响、对新斯的明致小肠运动亢进的拮抗作用;观察左金丸对组胺致豚鼠离体回肠收缩的影响;ig给予大鼠D-木糖溶液,1 h后测定血清木糖值,观察左金丸对大鼠小肠吸收的影响;ig给予小鼠蓖麻油,观察左金丸的止泻作用。以戊己丸（加味左金）和黄连有效成份小檗碱作参比。结果 左金丸对胃肠道有明显的调节作用,延长小鼠的胃排空时间,抑制胃排空;对正常小鼠小肠运动的无明显影响,但能明显拮抗新斯的明所致的小鼠小肠运动亢进;明显抑制组胺引起的豚鼠离体回肠收缩;明显抑制大鼠的小肠吸收功能;明显抑制蓖麻油造成的小鼠腹泻。结论 古方左金丸对胃肠道有明显的调节作用,组方科学、合理。     

Antidiarrheal,antisecretory, and bronchodilatory activities of Hypericum perforatum

This study describes the antidiarrheal, antisecretory, and bronchodilatory activities of Hypericum perforatum Linn. (Hypericaceae), commonly known as St. John’s wort, to justify its traditional use in the hyperactivity of the gastrointestinal and respiratory systems. The crude extract of Hypericum perforatum (Hp.Cr) at a dose of 500?mg/kg caused 20% protection against castor oil-induced diarrhea in mice and 60% at 1000?mg/kg (p?<?0.05 vs. saline). Hp.Cr at 300 and 1000?mg/kg reduced the castor oil-induced fluid accumulation in mice to 107.0?±?3.3?g (p?<?0.01) and 84.0?±?4.2?g (p?<?0.001) respectively, whereas in the castor oil-treated group, it was 126.9?±?3.9?g. When tested against carbachol (CCh)-mediated bronchoconstriction in rats under anesthesia, Hp.Cr dose-dependently (3–?30?mg/kg) suppressed the CCh (1?μmol/kg)-induced increase in the inspiratory pressure. Thus this study rationalizes the Hypericum perforatum usefulness in overactive gut and airways disorders, such as diarrhea and asthma.     

肠炎宁颗粒对幼龄小鼠的抗炎止泻作用及体外抗菌作用研究

目的 研究肠炎宁颗粒作用于ICR幼龄小鼠的止泻抗炎药效及体外抑菌作用,为其临床儿童用药提供参考。方法 以ICR幼龄小鼠为考察对象,ig给予高、中、低剂量（2.500、1.250和0.625 g/kg）肠炎宁颗粒及蒙脱石散（阳性药,4.2 g/kg）,连续给药3 d后,采用番泻叶浸出物和蓖麻油致泻模型、肠推进实验、冰醋酸致腹腔毛细血管通透性增加模型考察肠炎宁颗粒的止泻、抗炎作用;体外培养表皮葡萄球菌和大肠埃希菌,加入571.00、285.50、142.75、71.38、35.69、17.84、8.92、4.46、2.23和1.12 mg/mL的肠炎宁颗粒,观察其抑菌作用。结果 与模型组比较,0.625、1.250和2.500 g/kg的肠炎宁颗粒可以显著减少番泻叶浸出物、蓖麻油作用0~5 h内的腹泻样便数（P<0.05、0.001）;与对照组比较,2.5 g/kg的肠炎宁颗粒可以显著降低肠推进系数（P<0.05）;0.625、1.250和2.500 g/kg的肠炎宁颗粒可以显著减少冰醋酸所致的幼鼠腹腔毛细血管通透性增加（P<0.05、0.01）。8.92 mg/mL的肠炎宁颗粒即可在体外抑制表皮葡萄球菌和大肠埃希菌的生长,为最低抑菌浓度。结论 肠炎宁颗粒具有止泻、抑制肠胃推进及对抗急性渗出性炎症的作用;体外可以抑制表皮葡萄球菌和大肠埃希菌的生长。     

Comparative study of the anti-inflammatory and antinociceptive effects of two varieties of Punica granatum

Context: Studies have shown that pomegranate, Punica granatum Linn. (Lythraceae), has remarkable biological and medicinal properties.

Objective: This work aimed to explore and compare the analgesic and anti-inflammatory activities of the methanol extract (MoE) obtained from fruit peels of two varieties of pomegranate: Amrouz (MoEA) and Sefri (MoES).

Materials and methods: Antinociceptive activity of MoEA and MoES was examined using four models of pain. The extracts were administered by the intraperitoneal route (i.p.) in writhing (50, 100 and 150?mg/kg) and formalin tests (25, 50 and 100?mg/kg) and by intra-cerebroventricular injection (i.c.v.) in hotplate and tail-immersion tests (10, 25 and 50 µg/3 µl/rat). anti-inflammatory activity was studied using the hind paw egg albumin test (50, 100 and 150?mg/kg, i.p.).

Results: In the writhing test, the index of pain inhibition (IPI) was 52% for MoEA (150?mg/kg, i.p.) and 29% for MoES (150?mg/kg, i.p.). In the formalin test, the IPI of early and late phase were, respectively, 75% and 82% for MoEA (100?mg/kg, i.p.) and 8% and 63% for MoES (100?mg/kg, i.p.). In the hotplate and tail-immersion test, MoEA and MoES increased in a dosedependent manner the reaction latency to the thermal stimuli. MoEA seems to be more potent than MoES. Only the analgesic effect of MoEA was partially inhibited by pretreatment with naloxone. Both extracts exerted a significant anti-inflammatory effect.

Discussion and conclusions: The results demonstrated that P. granatum contains active constituents, which possess antinociceptive and anti-inflammatory activity, justifying its popular uses.     

Antidiarrheal mechanism of Carpolobia lutea leaf fractions in rats

Context: Carpolobia lutea G. Don (Polygalaceae) leaf is reputable as an antidiarrheal agent among the Efik and Ibibio tribe of Akwa Ibom State, Nigeria. The crude extract is reported to show antidiarrheal and antiulcer effects in rodents.

Objective: The isolation and characterization of drug molecules from the leaf fraction with antidiarrheal bioactivity and determination of mechanism of action are reported.

Material and methods: Gradient extraction by maceration yielding n-hexane, chloroform, ethyl acetate, and ethanol fractions (770?mg/kg) were used to establish the fractions suitable for drug discovery. The antidiarrheal effect of the leaf fractions of Carpolobia lutea was evaluated using castor oil–induced diarrhea, castor oil–induced intestinal transit, and enteropooling.

Results: Results indicate that all fractions produced a significant (p?<?0.01–0.001) decrease in castor oil–induced diarrhea in rats. This effect was not antagonized by isosorbide dinitrate (150?mg/kg, p.o), diphenoxylate (5?×?10^?3 mg/kg p.o) and yohimbine (1?mg/kg, s.c.) except for the chloroform fraction. The ethyl acetate fraction produced 100% inhibition of intestinal transit, an effect greater than pure drug. Phytochemical analysis of the ethyl acetate fraction yielded polyphenolic compounds.

Conclusion: The leaf fractions contain two types of antidiarrheal agents, one mediating its effect through α₁-presynaptic adrenoceptor while the other does not. Polyphenols isolated may in part lend credence for observed antidiarrheal activity.     

Antioxidant and antidiarrheal activities of ethanol extract of Ardisia elliptica fruits

Context: Ardisia elliptica Thunb Lam. (Myrsinaceae) is widely used traditionally in the treatment of diarrhea related health disorders in Bangladesh.

Objective: The crude ethanol extract of Ardisia elliptica fruits (EFA) was evaluated for its antioxidant and antidiarrhoeal activities.

Materials and methods: DPPH radical scavenging, nitric oxide scavenging, reducing power and Fe⁺⁺ ion chelating ability were used for determining antioxidant activities and animal models were used for antidiarrheal activities such as the castor oil and magnesium sulfate-induced diarrhea, enteropooling induced by the administration of castor oil and magnesium sulfate at the doses of 250 and 500?mg/kg.

Results: The extract possessed a significant DPPH free radical scavenging activity with an IC₅₀ value of 30.75?μg/ml compared to ascorbic acid (IC₅₀: 7.89?μg/ml). The IC₅₀ values of the extract and ascorbic acid were 51.72 and 38.68?μg/ml, respectively, in nitric oxide scavenging assay. The IC₅₀ value of the extract for Fe⁺⁺ ion chelating ability (41.30?μg/ml) was also found to be significant compared to the IC₅₀ value of EDTA (22.57?μg/ml). The EFA also showed a significant protection (p?Conclusion: Therefore, the obtained results confirm the antioxidant and antidiarrheal activity of EFA and thus support the traditional uses of this plant as a modality for antioxidant and antidiarrheal activity.     

Evaluation of the effects of Olea europaea L. subsp. africana (Mill.) P.S. Green (Oleaceae) leaf methanol extract against castor oil‐induced diarrhoea in mice

Objectives Olea europaea L. subsp. africana (Mill.) P.S. Green is widely used in South Africa by traditional medicine practitioners to treat diarrhoea. However, little is known scientifically about this South African species in the treatment of diarrhoea. The main aim of the study therefore was to investigate the antidiarrhoeal effect of the leaf methanol extract of the plant species in mice. Methods The antidiarrhoeal activity of the leaf methanol extract of O. europaea subsp. africana was studied using a castor oil‐induced diarrhoeal test. The antipropulsive activity of the plant extract was also investigated using the charcoal meal transit test. Standard methods were used to investigate the acute toxicity and effect of O. europaea subsp. africana on castor oil‐induced intraluminal fluid accumulation. Results Leaf methanol extract of O. europaea subsp. africana and loperamide, a standard antidiarrhoeal drug, significantly reduced the number of diarrhoeal episodes induced by castor oil, significantly decreased the stool mass, significantly delayed the onset of the diarrhoea and protected the animals against castor oil‐induced diarrhoea. Both O. europaea subsp. africana and loperamide significantly decreased the gastrointestinal transit of charcoal meal and castor oil‐induced intraluminal fluid accumulation in mice. The LD50 value was found to be 3475 mg/kg (p.o.). Conclusions The results obtained suggest that the leaf methanol extract of O. europaea subsp. africana has an antidiarrhoeal property and that, given orally, it may be non‐toxic and/or safe in mice.     

Evaluation of the antidiarrheal and antioxidant properties of Justicia hypocrateriformis

Content: Justicia hypocrateriformis Vahl (Acanthaceae) is used as an herbal remedy for diarrhea in Cameroon folk medicine.

Objective: This study evaluates the antidiarrheal and antioxidant properties of the aqueous extract of J. hypocrateriformis (JH).

Materials and methods: Preliminary phytochemical screening and an acute toxicity testing of the extract were carried out. The antidiarrheal activity of JH extract (100, 250, and 500?mg/kg) was assessed at curative and preventive levels in castor oil-induced diarrhea in mice. The antioxidant activity was measured by ferric reducing antioxidant power (FRAP), total phenolic content, and radical scavenging activity.

Results: A high lethal dose (LD₅₀) of 14.35?g/kg obtained in acute toxicity implies the extract is not toxic. Phytochemical screening revealed the presence of phenols, tannins, flavonoids, saponins, anthraquinones, and anthocyanins. JH showed a significant protection against castor oil-induced diarrhea as evidenced by a decrease in the number of defecation and wet stool. JH (100–500?mg/kg, p.o.) produced a non-significant dose-dependent decrease in castor oil-induced intestinal transit in the preventive study. In the curative and in healthy mice study, the decrease was only significant at 500?mg/kg. JH possessed a radical scavenging activity with an IC₅₀ of 9.93?mg/ml compared to 4.90?mg/ml for catechin. JH FRAP of 2703.77?±?0?mg/g (catechin equiv) and phenolic concentration of 14?169.99?±?612.39?mg/g (catechin equiv) were also obtained.

Conclusion: Justicia hypocrateriformis extract possesses antidiarrheal activity supported by its antioxidant potential and phytochemical constituents.     

Pharmacological investigations of Punica granatum in glycerol-induced acute renal failure in rats

Objective:

The present study was designed to investigate the ameliorative potential and possible mechanism of hydroalcoholic extract of flowers of P. granatum in glycerol-induced acute renal failure (ARF) in rats.

Materials and Methods:

The rats were subjected to rhabdomyolytic ARF by single intramuscular injection of hypertonic glycerol (50% v/v; 8 ml/kg) and the animals were sacrificed after 24 hours of glycerol injection. The plasma creatinine, blood urea nitrogen, creatinine clearance, and histopathological studies were performed to assess the degree of renal injury.

Results:

Pretreatment with hydroalcoholic extract of flowers of P. granatum (125 and 250 mg/kg p.o. twice daily for 3 days) significantly attenuated hypertonic glycerol-induced renal dysfunction in a dose-dependent manner. BADGE (Bisphenol-A-diglycidyl ether) (30 mg/kg), a peroxisome proliferator-activated receptor (PPAR)-γ antagonist, and N(omega)-nitro-l-arginine-methyl ester (L-NAME) (10, 20, and 40 mg/kg), nitric oxide synthase inhibitor, were employed to explore the mechanism of renoprotective effects of Punica granatum. Administration of BADGE (30 mg/kg) and L-NAME (40 mg/kg) abolished the beneficial effects of P. granatum in glycerol-induced renal dysfunction.

Conclusion:

Hydroalcoholic extract of flowers of P. granatum has ameliorative potential in attenuating myoglobinuric renal failure and its renoprotective effects involve activation of PPAR-γ and nitric oxide-dependent signaling pathway.     

Preliminary Investigation of the Oxytocic Action of an Aqueous Extract of Lagenaria breviflora Fruit

Abstract

The effects of an aqueous extract of Lagenaria breviflora Robert (Cucurbitaceae) fruit on pregnant and non-pregnant isolated rat uteri have been investigated.

The aqueous extract of L. breviflora fruit induced concentration-dependent, oxytocin-like contractions of the gravid and non-gravid isolated rat uteri. The extract-evoked contractions of the uterine strips examined were not modified by the standard antagonists used. The aqueous extract of L. breviflora fruit failed to contract the guinea-pig isolated ileum, whereas acetylcholine and histamine contracted this mammalian gastro-intestinal tract smooth muscle in a dose-related manner. The plausible pharmacological implications of these findings are discussed.     

Antidiarrheal potential of standardized extract of Rhododendron arboreum Smith flowers in experimental animals

Objective:

To investigate standardized ethyl acetate fraction of Rhododendron arboreum (EFRA) flowers for antidiarrheal activity in experimental animals.

Materials and Methods:

A simple sensitive high performance thin layer chromatography (HPTLC) method was used for the determination of hyperin in EFRA. The standardized fraction was investigated for castor oil, magnesium sulfate-induced diarrhea, measurement of gastrointestinal transit using charcoal and castor oil-induced enteropooling.

Results:

The concentration of hyperin in flowers of R. arboreum was found to be 0.148% by HPTLC. Oral administration of EFRA at 100, 200 and 400 mg/kg exhibited dose-dependent and significant (P<0.05-0.001) antidiarrheal potential in castor oil and magnesium sulfate-induced diarrhea. EFRA at doses of 100, 200 and 400 mg/kg also produced significant (P<0.05-0.001) dose-dependent reduction in propulsive movement in castor oil-induced gastrointestinal transit using charcoal meal in rats. EFRA was found to possess an antienteropooling in castor oil-induced experimental animals by reducing both weight and volume of intestinal content significantly.

Conclusion:

These findings demonstrate that standardized ethyl acetate fraction of R. arboreum flowers has potent antidiarrheal activity thus justifying its traditional use in diarrhea and have great potential as a source for natural health products.KEY WORDS: Antidiarrheal, enteropooling, gastrointestinal motility, high performance thin layer chromatography, Rhododendron arboreum     

Antidiarrhoeal activity of the standardised extract of <Emphasis Type="Italic">Cinnamomum tamala</Emphasis> in experimental rats

The present study was designed to investigate the antidiarrhoeal potential of 50% ethanolic extract of Cinnamomum tamala on experimentally induced castor oil diarrhoea, gastric emptying of phenol red meal, gastrointestinal transit of charcoal meal and in vitro mast cell degranulation activity. C. tamala extract (25, 50 and 100 mg/kg, orally) produced a dose-dependent reduction in the total amount of faecal matter in castor oil-induced diarrhoea. The mean distance travelled by charcoal meal at 50 and 100 mg/kg of extract showed a significant reduction in the secretion of gastrointestinal fluid accumulation by 32.5–65.0%. The Na⁺ and K⁺ concentrations on castor oil-induced fluid accumulation showed a greater inhibitory effect on Na⁺ levels than on K⁺ concentrations. C. tamala significantly reduced the lipid peroxidation (P < 0.001) and increased the catalase (P < 0.01) activity in comparison to the castor oil-induced groups. C. tamala leaf extract did not show any significant effect at a higher dose (15 mg/ml) on mast cell degranulation. However, the extract in the dose of 5 and 10 mg/ml conferred significant mast cell protective action (P < 0.001). The percentage of eugenol in extract is 3.8% w/w, and total tannin is 247.5 mg/g. The result indicates the Indian spice C. tamala is useful for diarrhoea.     

Pomegranate (Punica granatum) peel extract provides protection against mercuric chloride-induced oxidative stress in Wistar strain rats

Context: Pomegranate [Punica granatum L. (Lythraceae)] is rich in antioxidants.

Objective: The present work was undertaken to evaluate the protective effects of methanol extract of pomegranate peel extract (PPE) against a rat model of oxidative stress generated by treatment with mercuric chloride (HgCl₂).

Materials and methods: Rats were injected with HgCl₂ (5?mg/kg body weight in 0.9% NaCl) for developing oxidative stress. The methanol extract of pomegranate peel (PPE) was suspended in 0.5% sodium carboxymethylcellulose and fed to rats at 50?mg/kg body weight/day up to 30 days after HgCl₂ treatment. Biomarkers of oxidative stress including erythrocyte plasma membrane redox system (PMRS), lipid peroxidation, advanced oxidation protein products (AOPP), intracellular glutathione, and plasma antioxidant capacity as FRAP values were measured after PPE supplementation.

Results: HgCl₂-treated rats showed increased oxidative stress as evidenced by increased activity of erythrocyte PMRS 153%, lipid peroxidation 31%, and AOPP 290%. There was a significant (p < 0.01) decrease (25%) in plasma antioxidant capacity and intracellular glutathione (75%). Supplementation with PPE protected rats from HgCl₂ induced oxidative damage. PPE supplementation to control rats increased antioxidant defense.

Discussion and conclusion: The results clearly demonstrate that PPE treatment augments the antioxidant defense mechanism in mercuric chloride-induced oxidant toxicity. To the best of our knowledge this is the first report of the increase in erythrocyte PMRS activity in rats after supplementation with any kind of antioxidant supplementation. This study emphasizes the need for characterizing PPE for potential unknown antioxidant compounds.