Evaluation of antinociceptive and antidiarrhoeal properties of Manilkara zapota leaves in Swiss albino mice

Context Manilkara zapota (L.). P. Royen. (Sapotaceae) has been used in folk medicine to treat pain, diarrhoea, inflammation, arthralgia, and other disorders.

Objective Screening of Manilkara zapota leaves ethanol extract and its different solvent soluble fractions for possible antinociceptive and antidiarrhoeal activities in Swiss albino mice.

Materials and methods The extract and various fractions (200 and 400?mg/kg body weight; p.o.) were tested for peripheral and central antinociceptive activity by acetic acid-induced writhing and radiant heat tail-flick method, respectively; castor oil-induced diarrhoeal model was used to evaluate antidiarrhoeal activity at both doses. All the samples were administered once in a day and the duration of study was approximately 5?h.

Results Ethanol extract (400?mg/kg), petroleum ether fraction (400?mg/kg), and ethyl acetate fraction (400?mg/kg) showed significant peripheral antinociceptive activity having 59.89, 58.24, and 46.7% (p?<?0.001) of writhing inhibition, respectively, which is comparable with that of standard diclofenac (59.34% inhibition). The ethanol extract (400?mg/kg) and petroleum ether fraction (400?mg/kg) also showed promising central analgesic activity having 74.15 and 82.15% (p?<?0.001) elongation of reaction time, respectively, at 90?min after administration of sample which is also similar to that obtained by morphine (85.84% elongation). In antidiarrhoeal activity screening, ethanol extract (200 and 400?mg/kg) showed significant inhibition of defecation by 53.57 and 60.71%, respectively (p?<?0.001) compared with that of loperamide (71.42%).

Discussion and conclusion The findings of the studies demonstrated antinociceptive and antidiarrhoeal activities of M. zapota leaves which could be the therapeutic option against pain and diarrhoeal disease.     

Assessment of the antidiarrhoeal properties of the aqueous extract and its soluble fractions of Chebulae Fructus (Terminalia chebula fruits)

Context Chebulae Fructus is used as an herbal remedy for diarrhoea in traditional Chinese medicine. However, there is no scientific evidence to support its antidiarrhoeal activity.

Objective This study evaluates the antidiarrhoeal properties of Chebulae Fructus aqueous extract (CFAE) and determines the active fraction.

Materials and methods The antidiarrhoeal effect of CFAE (200–800?mg/kg) was investigated by determining the wet dropping, intestinal transit in BALB/c mice and enteropooling in Wister rats. The protective effects of the CFAE on the intestinal and liver were tested by histopathological analyses. The antidiarrhoeal fraction was determined by castor oil-induced diarrhoea and its main constituents were identified by HPLC-ESI-MS.

Results The extract at doses of 200, 400 and 800?mg/kg reduced the diarrhoea by 9.1, 40.0 and 58.2% and inhibited intestinal transit by 18.3, 24.1 and 35.7%, respectively. Additionally, the CFAE (200, 400 and 800?mg/kg) decreased the volume of enteropooling by 47.1, 58.8 and 64.7%, respectively. Mice treated with castor oil presented morphological alterations in the small intestine and the liver. However, the lesions of mice treated with CFAE were alleviated. Moreover, the ethyl acetate fraction was the active fraction of CFAE, the fraction (41.7, 83.4 and 166.8?mg/kg) reduced the diarrhoea by 9.1, 38.2 and 54.5%, respectively. The major components of the ethyl acetate fraction were tannins, including gallic acid, 3, 4, 6-tri-O-galloyl-β-d-Glc, corilagin and ellagic acid according to the HPLC-ESI-MS analysis.

Conclusion The CFAE possessed antidiarrhoeal property and the ethyl acetate fraction was its main active fraction.     

Hypoglycemic activity of aqueous seed extract of Hunteria umbellata in normal and streptozotocin-induced diabetic rats

The present study evaluated the aqueous seed extract of Hunteria umbellata K. Schum (Apocynaceae) for hypoglycemic activity in rats. Diabetes was induced by a single dose of streptozotocin (50?mg/kg i.p.). Daily doses of 400, 800, and 1000?mg/kg of extract were orally administered to fasted normal and diabetic rats. Blood glucose levels were monitored after 0, 2, 4, 8, 12?h and on day 14 post treatment. Liver glycogen levels were also estimated on day 14. In normal rats, only 400?mg/kg of the extract produced a significant reduction in blood glucose at the 4?h (P?<?0.05) which was 22.15?±?4.88%. In diabetic rats, the extract, 400, 800?mg/kg, caused significant reduction (P?<?0.01), 51.87% ± 5.79% and 43.47% ± 8.06% respectively, with maximum effect at 8?h. This reduction in blood glucose was greater than that of glibenclamide (31.03% ± 8.86%). Diabetic rats administered with 400?mg/kg extract produced a significant reduction (P?<?0.01) on day 14 (43.60% ± 8.10%). Liver glycogen levels were significantly increased (P?<?0.05) in diabetic rats administered with doses of 400 and 800?mg/kg extracts and these were comparable to glibenclamide. Acute toxicity data showed no mortality in mice up to 17.5?g/kg. We conclude that the extract possesses marked hypoglycemic effects in diabetic rats possibly through increased glycogenesis, thus justifying its use in herbal medicine for the treatment of diabetes.     

Hydroalcoholic extract of Myrtus communis can alter anxiety and sleep parameters: a behavioural and EEG sleep pattern study in mice and rats

Context: Myrtus communis L. (Myrtaceae), myrtle, is an evergreen shrub with strong antibacterial, anti-inflammatory, antihyperglycemic and antioxidant activities. Also, it is used as a sedative-hypnotic plant in Iranian traditional medicine.

Objective: This study evaluates the effect of 80% ethanolic extract of M. communis leaves on sleep and anxiety in mice and rats.

Materials and methods: Male NMRI mice were subjected to open field, righting reflex, grip strength and pentylentetrazole-induced seizure tests. Male Wistar rats were used to evaluate the alterations in rapid eye movement (REM) and non-REM (NREM) sleep. They were treated with 25–400?mg/kg doses of the extract intraperitoneally.

Results: The applied doses (50–200?mg/kg) of M. communis extract increased vertical (ED_50?=_?40.2?±?6.6?mg/kg) and vertical and horizontal activity (ED_50?=_?251?±?55?mg/kg), while treatment with 200 and 400?mg/kg attenuated muscle tone significantly compared to vehicle treated animals (p?<?0.001 for all) in a dose-independent manner. Also, a significant hypnotic and not anticonvulsant effect was observed when animals were treated with 200?mg/kg of the extract (p?<?0.01). In this regard, electroencephalography results showed that REM sleep time was decreased (2.4?±?0.5%), while total and NREM sleep times were increased significantly compared to the control group of mice (82.5?±?7.6%).

Discussion and conclusion: The data show the anxiolytic and muscle relaxant effect of the extract without anticonvulsant activities. The anxiolytic, myorelaxant and hypnotic effects without effect on seizure threshold are in line with the effect of a alpha 2 GABA receptor agonist.     

The effects of Melissa officinalis (lemon balm) pretreatment on the resistance of the heart to myocardial injury

Context: The antihyperlipidemic, antiarrhythmic, neuroprotective and hepatoprotective effects of Melissa officinalis L. (Lamiaceae) have been reported. However, no study has examined its effects on the resistance of the heart to stressful conditions.

Objective: The objective of this study is to evaluate the effects of aqueous extract of M. officinalis aerial parts on Wistar rat heart with/without cardiac injury.

Materials and methods: Animals were grouped as control, isoproterenol (ISO), M. officinalis without (M50, M100, and M200) and with isoproterenol (M50?+?ISO, M100?+?ISO, and M200?+?ISO). The aqueous extract of M. officinalis was orally administered at dosages of 50, 100, and 200?mg/kg/d, respectively, for 7 consecutive days. On the 6th and 7th day, ISO, M50?+?ISO, M100?+?ISO, and M200?+?ISO groups received 85?mg/kg of isoproterenol for myocardial injury induction. On day 8, hemodynamic parameters were recorded and samplings were done.

Results: The extract (50, 100, and 200?mg/kg) significantly reduced the heart rate (264?±?5, 259?±?5 and 281?±?3 versus 377?±?13 in control group, p?<?0.01). Blood pressure was significantly decreased in M50?+?ISO (75?±?5) versus M50 (110?±?6) and M100?+?ISO (72?±?6) versus M100 (105?±?5?mmHg, p?<?0.01). The malondialdehyde levels of the injured hearts were lower in M50?+?ISO and M100?+?ISO groups than in the ISO group (p?<?0.05). Serum cardiac troponin I was higher in the M200?+?ISO group (5.1?±?1.7) than in the ISO group (2.7?±?0.7?ng/ml, p?<?0.05).

Conclusion: The lower dose of extract, by improving the balance of the redox system and by reducing the heart rate, may increase the heart resistance to injury. However, the higher doses of extract may intensify the injury of ischemic heart.     

Effect of hydroalcoholic extract of Aegle marmelos fruit on radical scavenging activity and exercise-endurance capacity in mice

Context: Aegle marmelos L. Corr (Rutaceae) is an important Indian Ayurvedic medicinal plant used for the treatment of various ailments. However, little information is available on the anti-fatigue properties of its fruit.

Objective: Evaluation of the physical endurance and exercise-induced oxidative stress modulating properties of A. marmelos fruit in mice.

Material and methods: Radical scavenging activity of the fruit hydroalcoholic extract was evaluated using in vitro systems. The extract was further evaluated for its endurance-enhancing properties at three oral doses (100, 200 and 400?mg/kg?b.wt) in BALB/c mice for 21?d using a swimming test.

Results and discussion: The extract exhibited significant scavenging activity against DPPH (IC₅₀, 351?±?37?µg/ml) and ABTS radicals (IC₅₀, 228?±?25?µg/ml), respectively, with the polyphenol content of 95?µg/mg extract. It also inhibited AAPH radical-induced oxidation of biomolecules such as BSA protein (63%), plasmid DNA (81%) and lipids (80.5%). Administration of extract resulted in an increase in the duration of swimming time to exhaustion by 23.4 and 47.5% for medium and higher doses, respectively. The extract significantly normalized the fatigue-related biochemical parameters and also down-regulated the swim stress-induced over-expression of heat shock protein-70 and up-regulated the skeletal muscle metabolic regulators (GLUT-4 and AMPK1-α) by 2- and 3-fold, respectively, at the higher dose in muscle tissues.

Conclusion: Our study demonstrates the anti-fatigue properties of A. marmelos fruit, most probably manifested by delaying the accumulation of serum lactic acid, increasing the fat utilization and up-regulating the skeletal muscle metabolic regulators.     

Antiulcerogenic activity of extract, fractions, and some compounds obtained from Polygala cyparissias St. Hillaire & Moquin (Polygalaceae)

The present study evaluates the gastroprotective properties of acetone extract, chloroform, and methanol fractions, α-spinasterol (1); 1,3-dihydroxy-7-methoxyxanthone (2); and 1,7-dihydroxy-2,3-methylenedioxyxanthone (3) obtained from Polygala cyparissias (Polygalaceae). Gastroprotective assays were performed in mice using ethanol/HCl and nonsteroidal anti-inflammatory drug (NSAID)/bethanechol-induced ulcer models. Chloroformic fraction showed no interesting results. On the other hand, in the ethanol/HCl-induced ulcer model, the treatment using doses of 50, 125, and 250 mg/kg promoted ulcer inhibition of 45.19?±?12.93%, 62.99?±?3.49%, and 67.40?±?4.75% for acetone extract and 43.70?±?5.12%, 64.56?±?5.64%, and 74.49?±?6.13% for methanol fraction. In the model of NSAID/bethanechol-induced ulcer, the ulcer inhibitions in the same doses were 28.12?±?12.45%, 60.16?±?6.58%, and 77.86?±?7.18% for the acetone extract and 46.09?±?6.92%, 67.45?±?4.36%, and 75.00?±?2.92% for the methanol fraction. In view of the antiulcer potential of the acetone extract and its high yield and xanthone content, it was submitted to chromatographic procedures, giving compounds 1–3, which were also evaluated in the ethanol-induced ulcer model. The results showed that at a dose of 50 mg/kg, these compounds reduced the percentage of ulcer by around 71.26?±?9.40%, 81.10?±?5.75%, and 86.22?±?3.42%, for compounds 1, 2, and 3, respectively. The antiulcerogenic activity of P. cyparissias may be attributed, at least in part, to these compounds.     

Beneficial effect of Citrus limon peel aqueous methanol extract on experimentally induced urolithic rats

Context: Citrus limon (L.) Burm.f. (Rutaceace) is a commonly available fruit variety with high medicinal and industrial values.

Objective: Lemon peel (LP) extract was studied as a potent preventive and curative agent for experimentally induced hyperoxaluric rats.

Materials and methods: Gas chromatography–mass spectrometry (GC–MS) analyses and toxicity study were performed for aqueous methanol LP extract. Twenty-four Wistar rats were segregated into four groups. Group 1: Control; Group 2: Urolithic (ethylene glycol (EG) – 0.75%); Group 3: Preventive study (EG?+?LP extract administration from 0th to 7th week); Group 4: Curative study (EG?+?LP extract administration from 4th to 7th week). Animals received LP extract daily by oral administration (100?mg/kg body weight) for 7 weeks.

Results and discussion: GC–MS analyses revealed that compound 6 was abundant in the LP extract (32%) followed by compound 1 (～21%). The LD₅₀ value of LP extract was found to be >5000?mg/kg of body weight. Urolithic rats showed significantly higher urinary calcium and oxalate (4.47?±?0.44 and 18.86?±?0.55?mg/24 h, respectively) excretion compared with control and experimental rats. Renal function parameters like urea (84?±?8.5 and 96.1?±?3.6?mg/dL), creatinine (1.92?±?0.27 and 1.52?±?0.22?mg/dL), and urinary protein (2.03?±?0.02 and 2.13?±?0.16?mg/24 h) were also reduced by LP extract (p?<?0.001) and corroborated with tissue analyses (SOD, catalase, and MDA levels) and histological studies in normal and experimental animals. Immunohistochemical staining of THP and NF-κB in urolithic animals showed elevated expression than the control, while LP extract suppressed the expression of these proteins.

Conclusion: In conclusion, lemon peel is effective in curing kidney stone disease and also can be used to prevent the disease and its recurrence.     

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.     

Biochemical,hematological, and hormonal profile of rats orally administered methanol stem bark extract of Napoleona vogelii Hook and Planch (Lecythidaceae)

Napoleona vogelii is used in traditional medicine for the management of stomach aches, ulcer, and cancers. This study was conducted to investigate the subchronic toxicological effect of methanol stem bark extract of N. vogelii on biochemical, hematological, and hormonal profile of male and female rats. Forty rats of both sexes were randomly divided into four groups of 10 rats each and were administered 100, 200, and 400?mg/kg of the extract p.o. for 90?d. Ten?milliliter per kilogram of distilled water p.o. was administered to control rats. On hematological assessment, mean corpuscular hemoglobin concentration was significantly (p?<?0.01) increased at 400?mg/kg compared to control. Biochemical assessment showed a significant increase (p?<?0.05) in levels of alanine aminotransferase and aspartate aminotransferase at 200 and 400?mg/kg, respectively, compared to control. Hormonal assessment of male rats revealed a significantly (p?<?0.0001) reduced level of testosterone at all treatment doses compared to control while estradiol was significantly (p?<?0.05) reduced at 100?mg/kg, but significantly (p?<?0.0001) increased at 200 and 400?mg/kg respectively compared to control in female rats. Findings from this study demonstrate that N. vogelli is relatively safe on oral acute exposure but may possess the potential to cause hepatic dysfunction and infertility in male rats by perturbations of the hypothalamic-pituitary axis while conversely enhancing fertility in female rats on subchronic administration.     

Anti-Helicobacter pylori and antiulcerogenic activity of Aframomum pruinosum seeds on indomethacin-induced gastric ulcer in rats

Context: Peptic ulcer is one of the most common diseases affecting mankind. Although there are many products used for its treatment, most of these products produce severe adverse reactions requiring the search for novel compounds. Some Afromomum species are used traditionally to cure acute gastritis.

Objective: To evaluate the antiulcer activity of the methanol extract of Aframomum pruinosum Gagnepain (Zingiberaceae) seeds against two major etiologic agents of peptic ulcer disease; Helicobacter pylori and non-steroidal anti-inflammatory drugs.

Materials and methods: The anti-Helicobacter activity of A. pruinosum was evaluated using the broth microdilution method. After oral administration of indomethacin (5?mg/kg) for 5 consecutive days, gastric ulcerated animals were divided into control group and five other groups: three groups that recieved respectively 125, 250 and 500?mg/kg of plant extract, the fourth group received Maalox (50?mg/kg) and the fifth group, Misoprostol (100?μg/kg), respectively, for 5 days. Ulcer areas, gastric mucus content and nitric oxide gastric levels of animals were assessed 24?h after this treatment.

Results: A. pruinosum extract shows a moderate anti-Helicobacter activity with an MIC value of 128?μg/mL. A. pruinosum extract, like Misoprostol and Maalox, markedly reduces the % of ulcerated area from 8.15?±?0.33 to 1.71?±?0.44% (500?mg/kg). It also increased significantly mucus and NO gastric production with respective values of 4.44?±?1.35 and 965.81?±?106.74?μmol/g (500?mg/kg).

Discussion and conclusion: These findings suggest that A. pruinosum methanol extract possesses antiulcer properties as ascertained by the comparative decreases in ulcer areas, increase of mucus and NO gastric production.     

Pharmacological properties of lichen Cladonia clathrata

Cladonia clathrata Ahti & L. Xavier-Filho (Cladoniaceae) is a lichen; several Cladonia species extracts have been used for various remedies in folk medicine. In order to evaluate the actions of this lichen, studies were performed on antinociceptive, anti-inflammatory, and antioxidant activities. The hydroalcoholic extract (HE) of C. clathrata stems was used in the following experiments. Oral treatment with the HE of C. clathrata elicited inhibitory activity (p?<?0.001) on acetic acid-induced abdominal writhes at 100 (47.2%), 200 (47.2%), and 400?mg/kg (86.4%), and reduced the formalin-induced nociception on both the neurogenic (400?mg/kg, p?<?0.01) and inflammatory phases (200 and 400?mg/kg, p?<?0.01). It was not associated with non-specific effects, such as muscle relaxation or sedation. The HE reduced the carrageenan-induced edema formation at 100, 200, and 400?mg/kg (p?<?0.05) and inhibited neutrophil migration into the peritoneal cavity at 400?mg/kg (p?<?0.001). The HE of C. clathrata reacted with the DPPH radical and reduced the same by 50.19%, and exhibited an IC₅₀ value of 69.25?±?0.65 μg/mL. The HE of C. clathrata stems shows antinociceptive and anti-inflammatory activities, with a moderate antioxidant potential.     

Proulcerogenic effect of water extract of Boswellia sacra oleo gum resin in rats

Context: The water extract of Boswellia sacra Flueck. (Burseraceae) is used in the treatment of gastric and hepatic disorders in the Arab countries.

Objective: The effect of Boswellia sacra water extract on gastric secretion and experimentally induced gastric ulcers in rats was studied.

Materials and methods: Acetic acid-induced chronic gastric ulcers, pylorus ligation, aspirin-induced, ethanol-induced, and restraint plus cold stress-induced gastric ulcer models were employed. The effect on normal rats was also studied. The water extract of B. sacra was administered orally at doses of 2 and 5?ml/kg once daily ranging from single dose to 30?d treatment depending on the model. The extract was subjected to GC-MS analysis to determine the presence of various phytoconstituents.

Results: Boswellia sacra water extract (5?ml/kg, p.o (per os)) aggravated acetic acid-induced chronic ulcers, wherein an increase in ulcer index (p?<?0.01) and ulcer score (p?<?0.05) was observed. In pylorus-ligated rats, the extract increased gastric content volume (p?<?0.01), free acidity (p?<?0.01), total acidity (p?<?0.01), ulcer index (p?<?0.01), and pepsin activity (p?<?0.05). There was no significant effect on the development of ethanol-induced and aspirin-induced ulcers while an increase in the development of stress-induced ulcers was observed (p?<?0.01). The extract did not produce any ulcers when administered to normal rats. The dose of 2?ml/kg was less proulcerogenic compared with 5?ml/kg. The GC-MS analysis revealed the presence of several phytoconstituents that included menthol, 3-cyclohexen-1-ol, and octanoic acid.

Conclusion: Boswellia sacra water extract has proulcerogenic activity due to its gastric hypersecretory effect.     

Nephroprotective and curative effects of Ficus religiosa latex extract against cisplatin-induced acute renal failure

Abstract

Context. Ficus religiosa L. (Moraceae) is widely planted in the tropics. Its chemical constituents include tannin, saponin gluanol acetate, β-sitosterol, leucoanthocyanidin and leucoanthocyanin which are used for the treatment of pain, inflammation, impotence, menstrual disturbances, uterine tonic and urine related problems.

Objective: To determine the possible nephroprotective and curative effects of F. religiosa latex methanol extract against cisplatin induced acute renal failure.

Materials and methods: Methanol extract was obtained by maceration process. Rats were divided in five groups. Group 1 was administered acacia (2% w/v) of 5?ml/kg throughout the experiment; group 2 was treated with single dose of cisplatin (5?mg/kg i.p.) on the 1st day; group 3 (200?mg/kg p.o.) of extract control for the 1st to 10th day, group 4 (200?mg/kg p.o.) of extract from the 1st to 10th day and a single dose of cisplatin (5?mg/kg, i.p.) on 11th day while group 5 received the same dose of cisplatin on day 1 and extract (200?mg/kg p.o.) from the 7th to 16th day.

Results: Phytochemical screening of the extract revealed the presence of glycoside, alkaloids, tannins (phenolic compounds), flavonoids and amino acids. The half maximal inhibitory concentration (IC₅₀) values of the extract were 31.75?±?0.12 and 18.35?±?0.48?µg/ml, respectively. The cisplatin-treated group 2 showed significant changes; renal functions, biochemical parameters and histopathology were significantly (**p?<?0.01) recovered by 200?mg/kg curative and protective groups.

Discussion and conclusion: These findings demonstrated that F. religiosa latex and constituents have excellent nephroprotective and curative activities and thus have great potential as a source for natural health products.     

Antidiarrheal and antiulcer activity of Amaranthus spinosus in experimental animals

The ethanol extract (50%) of the whole plant of Amaranthus spinosus Linn. (Amaranthaceae) (ASE) significantly inhibited travel of a charcoal meal at three different doses of ASE, but when 400?mg/kg of ASE was repeated in the presence of yohimbine, intestinal propulsive inhibition decreased, while morphine reversed the activity. The percentages related to controls for the onset of diarrhea were 16.58, 83.42, and 116.18% at doses of 100, 200, and 400?mg/kg of ASE, while with morphine this value was 123.93% compared to controls. The percentage purging frequency related to controls was 41.09, 64.38, 71.23, and 86.30% at three different doses of ASE and with morphine, respectively. The inhibitions in intestinal accumulation were 8.9, 48.16, and 68.06% at doses of 100, 200, and 400?mg/kg of ASE, respectively, compared to control, while inhibition with yohimbine was 50.78%. Antidiarraheal indices of ASE were 23.55, 49.16, and 76.53 at the three different doses of ASE, while morphine had a maximum index of 88.45. Protection in ethanol- induced ulcer was 51.07, 55.91, 77.95, and 60.75%, but in aspirin-induced ulcer it was 41.33, 61.77, 80.88, and 74.66% at doses of 100, 200, and 400?mg/kg of ASE and with cimetidine, respectively. Lipid peroxidation was also associated with a concomitant decrease in ulcer index, while protection was 56.96, 63.29, 81.01, and 52.32% at three different doses of ASE and with cimetidine in cold restraint-induced ulcer.     

Protective effects of Osbeckia octandra against paracetamol-induced liver injury

1. Osbeckia octandra is a plant used in traditional medicine to treat jaundice and other liver disorders. In this study, the effects of Osbeckia leaf extract on paracetamol-induced liver injury were investigated both in vivo in mice and in rat hepatocytes in vitro.

2. Oral administration of Osbeckia extract (330?mg/kg) at the same time as paracetamol (450?mg/kg) to mice, resulted in a significant protection (p<0.05) against liver damage, as assessed by improvements in the blood Normotest (39.1 ± 1.9 versus 46.3 ± 2.0?s), total liver glutathione (730 ± 39 versus 574 ± 27 μg/250?mg liver), plasma aspartate aminotransferase level (916 ± 225 versus 1965 ± 291 iu/l), and liver histopathology at 24?h after paracetamol administration.

3. In experiments to assess the direct effects of Osbeckia extract, significant protection was also found in freshly isolated rat hepatocytes against damage induced by 185 μM 2,6-dimethyl N-acetyl p-quinoneimine (2,6-diMeNAPQI, an analogue of NAPQI, the toxic metabolite of paracetamol) in vitro. When Osbeckia extract (500 μg/ml) was added to the incubation medium at the same time as 2,6-diMeNAPQI significant changes in cell viability (78.4 ± 3.3 versus 47.2 ± 5.8% of control, p<0.001), cell reduced glutathione (GSH) level (35.0 ± 3.1 versus 23.8 ± 1.5%, p = 0.009), and reduced release of lactate dehydrogenase (129.9 ± 6.6 versus 224.6 ± 12.1%, p<0.001) were demonstrated after 1?h incubation as compared with 2,6-diMeNAPQI alone.

4. Significant protection was still obtained against 2,6-diMeNAPQI in vitro when addition of Osbeckia extract was delayed by 20?min. These results indicate that Osbeckia extract can protect against paracetamol-induced liver injury.     

Antidiabetic,antilipidemic, and antioxidant activities of Gouania longipetala methanol leaf extract in alloxan-induced diabetic rats

Abstract

Context: Gouania longipetala Hemsl. (Rhamnaceae) is used in folkloric medicine for treating diabetes mellitus and its associated symptoms.

Objective: This study evaluated the antidiabetic antilipidemic and antioxidant activities of the plant methanol leaf extract.

Materials and methods: Diabetes was induced in rats by intraperitoneal injection of alloxan monohydrate (160?mg/kg). Three test doses (50, 100, and 150?mg/kg) of G. longipetala extract (GLE) were administered orally and the effects were compared with glibenclamide (2?mg/kg). The effect of GLE on hyperglycemia and sub-acute study for 21?d were carried out using its effect on fasting blood sugar (FBS) level. Serum biochemistry and antioxidant activity were evaluated. Histopathological evaluation of the pancreas was also done.

Results: The LD₅₀ of G. longipetala was found to be >4000?mg/kg. The extract significantly (p?<?0.0001) decreased the FBS levels of treated rats from 16.2?±?2.03 to 6.5?±?1.52?mM/L at 150?mg/kg within 24?h. The extract decreased FBS levels of rats by 62.0, 74.8, and 75.0% on day 21 at 50, 100, and 150?mg/kg, respectively. GLE reduced the level of malondiadehyde from 23.0?±?1.34?to 10.3?±?0.43?mg/dL, increased superoxide dismutase activities from 2.97?±?0.34 to 5.80?±?0.53?IU/L at 150?mg/kg, and improved the serum lipid profile of treated rats. GLE also caused restoration of the altered histopathological changes of the pancreas.

Discussion and conclusion: Gouania longipetala demonstrated significant antidiabetic, antilipidemic, and antioxidant activities that may be due to its multiple effects involving both pancreatic and extra-pancreatic mechanisms.     

Lipid-lowering property of Clausena anisum-olens in hypercholesterolemic rats

Context: Clausena anisum-olens (Blanco) Merr. (Rutaceae) is a medicinal shrub which has been reported to have various pharmacological uses. No study regarding the effects of C. anisum-olens on cholesterol-lowering has been reported.

Objective: The effects of the ethanol extract of C. anisum-olens leaves on the cholesterol level of hypercholesterolemic rats were evaluated.

Materials and methods: Acute oral toxicity of the extract (175, 550 and 2000?mg/kg) was determined using female Sprague-Dawley rats, as described in OECD 425 Main test guidelines. The lipid-lowering assay utilized 30 male Sprague-Dawley rats divided into five groups (A–E). Triton X-100 was administered to induce hypercholesterolemia. After hypercholesterolemia induction, oral treatment of Atorvastatin and crude ethanol extract was given daily to the treatment groups for 14 days. The total cholesterol, triglycerides, HDL and LDL were determined before induction, after induction, after first week of treatment and after second week of treatment.

Results: Acute oral toxicity showed the crude extract is nontoxic up to 2000?mg/kg. The lipid-lowering assay indicated reduction of serum cholesterol (87.21?±?5.10?mg/dL), triglycerides (58.09?±?4.10?mg/dL) and LDL (27.82?±?4.11?mg/dL) for 200?mg/kw extract. Reduction in serum cholesterol (74.72?±?3.64?mg/dL), triglycerides (52.79?±?2.98?mg/dL) and LDL (12.06?±?5.51?mg/dL) were observed for 400?mg/kg group. The result is comparable to Atorvastatin, which showed serum cholesterol (80.90?±?9.72?mg/dL), triglycerides (55.94?±?7.19?mg/dL) and LDL (22.09?±?7.60?mg/dL) reduction.

Discussion and conclusion: The crude extract of C. anisum-olens proved to be useful in lowering of cholesterol.     

In vitro immunomodulatory activity and in vivo anti-inflammatory and analgesic potential with gastroprotective effect of the Mediterranean red alga Laurencia obtusa

Context: Red algae have been recognized as a rich natural source of compounds possessing interesting biological and pharmacological activities.

Objective: This work investigates anti-inflammatory, analgesic and gastroprotective activities of MeOH/CH₂Cl₂ crude extract and its fractions F1 (50% MeOH) and F2 (80% MeOH) from the whole alga plant Laurencia obtusa Hudson (Rhodomelaceae).

Materials and methods: Anti-inflammatory activity was evaluated in vitro using cytometric bead array (CBA) technology to follow up the secretion of tumour necrosis factor alpha (TNF-α) in lipopolysaccharide activated THP-1 monocytic cells at doses of 10–250?μg/mL and in vivo using carrageenan-induced paw oedema in Wistar rats at doses of 25, 50, 100 and 200?mg/kg. Crude extract and fractions were tested at the doses of 25, 50, 100 and 200?mg/kg for peripheral and central analgesic activity by acetic acid-induced writhing test and hot-plate method, respectively, in Swiss albino mice. Gastroprotective activity was evaluated using HCl/ethanol-induced gastric ulcer test in rats at doses of 25, 50, 100 and 200?mg/kg.

Results: Crude extract, F1 and F2 showed an interesting inhibition of TNF-α secretion with IC₅₀ values of 25, 52 and 24?μg/mL, respectively, and a significant anti-inflammatory activity in vivo (p?< 0.01), 3?h after carrageenan injection, the oedema inhibition was 55.37%, 52.18% and 62.86%, respectively, at the dose of 100?mg/kg. Furthermore, they showed a significant peripheral analgesic activity with 53.79%, 55.92% and 57.37% (p?< 0.01) of writhing inhibition, respectively. However, no significant activity was found in the hot-plate test. An interesting gastroprotective effect was observed with crude extract and its fractions F1 and F2 with a gastric ulcer inhibition of 65.48%, 77.42% and 81.29%, respectively, at the dose of 50?mg/kg.

Discussion and conclusion: These results suggest that L. obtusa might be used as a potential source of natural anti-inflammatory and analgesic agents with gastroprotective effect.     

Antipyretic and antimalarial activities of Solenostemon monostachyus

Context: Solenostemon monostachyus P. Beauv (Lamiaceae) is an important herb used traditionally in the treatment of malaria, fever, and other diseases.

Objectives: Antiplasmodial and antipyretic activities of S. monostachyus aerial extract were evaluated to ascertain the folkloric claim of its antimalarial and antipyretic activities.

Materials and methods: The extract (75–225?mg/kg) and fractions (chloroform and aqueous; 150?mg/kg) of S. monostachyus were investigated for suppressive, prophylactic, and curative antiplasmodial activities against chloroquine-sensitive Plasmodium berghei infections in Swiss albino mice and for antipyretic activity against 2,4-dinitrophenol and yeast-induced pyrexia. Artesunate (5?mg/kg) and pyrimethamine (1.2?mg/kg) were used as positive controls for antiplasmodial models. Thin films made from tail blood of each mouse were used to assess the level of parasitaemia of the mice.

Results: The extract/fractions progressively reduced parasitaemia induced by chloroquine sensitive P. berghei infection in prophylactic (28.48–71.72%), suppressive (12.52–72.47%), and curative (22.4–82.34%) models in mice. These reductions were statistically significant (p?<?0.01–0.001). They also improved significantly (p?<?0.01–0.001) the mean survival time (MST) from 12.26 to 25.63?d relative to control (11.36?d). The activities of extract/fractions were incomparable with that of the standard drugs used (artesunate and pyrimethamine). The extract exerted prominent inhibition of pyrexia on dinitrophenol (87.33–90.11%, 5?h) and yeast (56.22–65.33, 5?h) induced pyrexia. Inhibition was significant (p?<?0.05–0.001) from 3 to 5?h post-administration of extract and in a dose-dependent fashion.

Conclusion: The plant may possess antiplasmodial and antipyretic effects which may in part be mediated through the chemical constituents of the plant.