Evaluation of the sub-acute toxicity of the sclerotium of Lignosus rhinocerus (Cooke), the Tiger Milk mushroom

Ethnopharmacological relevance

Lignosus rhinocerus (known locally as ‘Tiger Milk mushroom’) is the most important medicinal mushroom used by the indigenous communities of Malaysia to treat fever, cough, asthma, cancer, food poisoning and as a general tonic. The sclerotium of the mushroom is the part with medicinal value. Lignosus rhinocerus was hitherto unexploited commercially because of limited supply. Recently, the mushroom was successfully cultivated.

Materials and methods

Sprague Dawley rats (5 rats/group/sex) were fed orally with 250, 500 and 1000 mg/kg TM02, 1000 mg/kg TM03 as well as 1000 mg/kg wild type Lignosus rhinocerus sclerotial powder. Sclerotial powder was orally administered once daily and consecutively for 28 days. Body weight of each animal was measured and any gross behavioral change was observed daily. Hematological and clinical biochemical parameters as well as histopathological analysis were carried out on 29th day.

Results

The results showed that oral administration of the sclerotial powder at daily dose of up to 1000 mg/kg had no adverse effect on the growth rate, hematological and clinical biochemical parameters (including renal and liver function parameters). Histological studies showed that the treatments did not induce any pathological changes in the liver, kidney, heart, spleen and lung of the animals.

Conclusion

In conclusion, our results show that there was no treatment-related sub-acute toxicity in rats following 28-days oral administration of 250, 500 and 1000 mg/kg TM02, 1000 mg/kg TM03 as well as 1000 mg/kg wild type Lignosus rhinocerus sclerotial powder. As the highest tested dose of 1000 mg/kg was not associated with any toxicity concern, the NOAEL dose is higher than 1000 mg/kg.     

Hypoglycemic and antihyperglycemic effect of Witheringia solanacea in normal and alloxan-induced hyperglycemic rats

Aim of the study

Witheringia solanacea is a small shrub that belongs to the Solanaceae family. The plant is used as an antidiabetic in Costa Rican herbal medicine. The aim of this study was to evaluate the hypoglycemic and antihyperglycemic activity of the aqueous extract of W. solanacea leaves in rodent models.

Materials and methods

A crude extract of W. solanacea leaves was prepared in boiling water and the aqueous filtrate was lyophilized. A single oral dose of 250, 500 and 1000 mg/kg of the extract was evaluated for hypoglycemic activity in a glucose tolerance test in normal rats and for antihyperglycemic activity in alloxan-induced (140 mg/kg) diabetic rats. The blood glucose level was determined at different times by the glucose oxidase method.

Results

Dosage of 500 and 1000 mg/kg of the extract significantly decreased (p < 0.05) blood glucose levels in the glucose tolerance test in normal rats after 1 h, there was no significant difference observed at 250 mg/kg. Dose of 500 mg/kg of the extract significantly reduced (p < 0.05) blood glucose levels in alloxan induced hyperglycemic rats at 4 and 5 h.

Conclusions

In the present study, the hypoglycemic and antihyperglycemic potential of the W. solanacea was demonstrated in rats. These results give support to the traditional use of W. solanacea as antidiabetic herbal medicine.     

Alpha-momorcharin possessing high immunogenicity, immunotoxicity and hepatotoxicity in SD rats

Momordica charantia L., a genus of Momordica Linn. of the family Cucurbitaceae, commonly known as bitter melon, has been widely planted in China, Southeast Asia, Turkey and other areas, and has been used as a medicine for a long time. Alpha-momorcharin (α-MMC) extracted and purified from bitter melon seeds has significant anti-tumor and anti-virus effects, and has potential toxicity as well, especially when taken overdose. However, up to date studies on its safety evaluation are still insufficient.

Aims of the study

The immunogenicity, immunotoxicity and general toxicity of α-MMC were investigated in rats and guinea-pigs, and the potential toxic effects of the agent on the body were also examined.

Materials and methods

The major ribosome-inactivating protein was isolated by column chromatographies from the protein extracted from bitter melon seeds, and was verified as α-MMC. After rats were immunized by α-MMC, titers of specific antibody to α-MMC in immunized rats serum were detected by indirect ELISA. Guinea-pigs and rats immunized with α-MMC were used to evaluate the active systemic anaphylaxis and passive cutaneous anaphylaxis induced by α-MMC relatively. α-MMC of 6.25 mg/kg, 2.08 mg/kg and 0.70 mg/kg was administered to rats every 2 days. Five weeks later, animals were sacrificed, and then, biochemical examination, analysis of bone marrow and peripheral blood cells, and histopathologic examination were performed.

Results

The ribosome-inactivating protein isolated and purified from bitter melon seeds was identified as α-MMC. It induced high titer (1:46.4) of specific IgG and high positive results of the active systemic anaphylaxis and passive cutaneous anaphylaxis tests in animals. With the time of the α-MMC administration increasing, the body weights of the animals administered with α-MMC of 6.25 mg/kg decreased significantly, and point necrosis was also observed in liver cells, along with abnormal findings in serum chemistry, hematology and bone marrow histopathology test. The toxic effect lessened with the decrease of the dose of α-MMC and further reduced after the convalescence stage.

Conclusions

The results of the study show that α-MMC has high immunogenicity and immunotoxicity, and can cause obvious organic liver lesion.     

Hypoglycemic effect of a leaf extract of Pseuderanthemum palatiferum (Nees) Radlk. in normal and streptozotocin-induced diabetic rats

Ethnopharmacological relevance

Pseuderanthemum palatiferum (Nees) Radlk (Acanthaceae) was first found in Northern Vietnam and expanded throughout the country including the Mekong Delta region. The leaves of this plant are recommended in folk medicine of Vietnam and Thailand for promoting and treating various diseases including hypertension, diarrhea, arthritis, hemorrhoids, stomachache, tumors, colitis, bleeding, wounds, constipation, flu, colon cancer, nephritis, and diabetes.

Aim of the study

The hypoglycemic effect of an 80% ethanolic leaf extract from the leaves of Pseuderanthemum palatiferum (PPE) was investigated in normal and streptozotocin (STZ)-induced diabetic rats.

Materials and methods

The PPE was administered daily and orally to the rats at the doses of 250, 500, and 1000 mg/kg body weight (b.w.) for 14 days. The levels of fasting plasma glucose (FPG), serum insulin, and biochemical data such as blood urea nitrogen (BUN), triglycerides (TG), total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and alkaline phosphatase (ALP) were evaluated. The hypoglycemic effect of PPE was compared to that of the known anti-diabetic drug glibenclamide (0.25 mg/kg b.w.).

Results

FPG and serum insulin in normal rats were not significantly different from the control and test groups in all dosages. The treated diabetic rats which had received PPE and glibenclamide showed significantly (p < 0.05) decreased FPG and increased serum insulin levels at the end of the experiment. The hypoglycemic effect of PPE at the dose of 250 mg/kg b.w. was significantly (p < 0.05) more effective than that of glibenclamide. The serum insulin in PPE fed diabetic rats at the dose of 250 mg/kg b.w. was not different from those which had received glibenclamide, and this dose was significantly (p < 0.05) more effective than PPE at the doses of 500 and 1000 mg/kg b.w. while PPE increased HDL and decreased TC, TG, LDL, BUN and ALP in the diabetic rats.

Conclusions

PPE has a beneficial effect in hyperglycemic rats and may prevent the complication of diabetes.     

Effects of lignans extracted from Eucommia ulmoides and aldose reductase inhibitor epalrestat on hypertensive vascular remodeling

Aim of the study

To investigate the effects of lignans extracted from Eucommia ulmoides and epalrestat on vascular remodeling in spontaneously hypertensive rats.

Materials and methods

Ten-week-old male spontaneously hypertensive rats were randomly divided into 3 groups (12 rats each group), and treated orally with 100 mg/kg/d of captopril (an angiotensin-converting enzyme inhibitor), 100 mg/kg/d of epalrestat (an aldose reductase inhibitor) and 300 mg/kg/d of lignans by gavage daily for 16 weeks, respectively. Sex-, age-, and number-matched spontaneously hypertensive rats and normotensive Wistar Kyoto rats, were treated with distilled water (vehicle) as controls. The rats were weighed weekly. Mean arterial blood pressure and heart rate were measured periodically by non-invasive blood pressure monitoring. They were sacrificed at the end of experiment (26-week-old). Superior mesenteric artery and aorta were isolated for determination of histomorphometry and the expression of aldose reductase by immunohistochemistry.

Results

Captopril and lignans, but not epalrestat, decreased mean arterial blood pressure in spontaneously hypertensive rats. Vascular remodeling was improved in all three treated groups by histomorphometry.

Conclusions

Both lignans and epalrestat reversed hypertensive vascular remodeling. Aldose reductase played a vital role in the pathologic process of hypertensive vascular remodeling rather than elevation of blood pressure. These data suggested that aldose reductase could be a new therapeutic target for the treatment of cardiovascular diseases.     

Hepatoprotective activity of the edible snail (Bellamia bengalensis) flesh extract in carbon tetrachloride induced hepatotoxicity in rats

Ethnopharmacological relevance

In the folk-traditional medicine, snails were used to purify blood, boost immune system, prevent conjunctivitis and to treat liver problems.

Objectives

To evaluate the hepatoprotective activity of the edible snail (Bellamia bengalensis) flesh extract in male Wistar rats treated with carbon tetrachloride as an hepatotoxicant.

Materials and methods

Live adult Bellamia bengalensis was collected commercially from the Kolkata market. Aqueous flesh extract (BBE) was prepared in 0.9% saline and expressed in terms of wet weight basis. The aqueous flesh extract was administered orally (1, 2 g kg⁻¹ day⁻¹) to male rats for 12 days. Liv52 was used as positive control. 24 h after administration of extract, the rats were given a single oral dose of CCl₄ (1.25 ml kg⁻¹), except vehicle control rats. After 24 h of CCl₄ administration, all the animals were sacrificed to collect the blood and liver tissue.

Results

BBE (1 and 2 g kg⁻¹ day⁻¹, p.o. × 12 days) significantly prevented CCl₄ induced elevation of SGOT, SGPT, γGT, ACP, ALP, bilirubin, LDH and CCl₄ induced decrease in total protein, triglyceride level in male Wistar rats. BBE treated rat liver anti-oxidant parameters (LPO, SOD, GSH, CAT, GPx) were significantly antagonized for the pro-oxidant effect of CCl₄. Histopathological studies also supported the protective effect of BBE.

Conclusion

This study validated the folk and traditional use of snail in liver disorder through CCl₄-induced rat experimental model.     

Hypoglycaemic activity and molecular mechanisms of Caesalpinia ferrea Martius bark extract on streptozotocin-induced diabetes in Wistar rats

Ethnopharmacological relevance

The tea from the stem bark of Caesalpinia ferrea Martius (Leguminosae) has been popularly used in the treatment of diabetes in Brazil.

Aim of the study

To investigate the hypoglycaemic properties and to elucidate the mechanisms by which the aqueous extract of the stem bark of Caesalpinia ferrea reduces blood glucose levels in streptozotocin-induced diabetic rats via the enzymatic pathways of protein kinase B (PKB/Akt), AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC).

Materials and methods

The aqueous extract of the stem bark of Caesalpinia ferrea (300 and 450 mg/kg/day), vehicle and metformin (500 mg/kg/day) were administered orally to STZ-diabetic rats (n = 7/group) for 4 weeks. Changes in body weight, food and water intake, fasting glucose levels and oral glucose tolerance were evaluated. Phosphorylation (P) and the expression of Akt, AMPK and ACC in the liver and skeletal muscle were determined using Western blot.

Results

The aqueous extract of the stem bark of Caesalpinia ferrea reduced blood glucose levels and improved the metabolic state of the animals. P-Akt was increased in the liver and skeletal muscle of the treated animals, P-AMPK was reduced only in the skeletal muscle of these animals and P-ACC was reduced in both when compared with untreated rats.

Conclusion

The results indicate that the aqueous extract of the stem bark of Caesalpinia ferrea has hypoglycaemic properties and possibly acts to regulate glucose uptake in liver and muscles by way of Akt activation, restoring the intracellular energy balance confirmed by inhibition of AMPK activation.     

In vivo antiulcer activity of the aqueous extract of Bauhinia purpurea leaf

Ethnopharmacological relevance

Bauhinia purpurea (Fabaceae) is a medicinal plant traditionally used to treat various ailments, including ulcers. In order to establish pharmacological properties of the leaf of Bauhinia purpurea, studies were performed on antiulcer activity of the plant's aqueous extract.

Materials and methods

The Bauhinia purpurea aqueous extract (BPAE) was prepared in the doses of 100, 500 and 1000 mg/kg. Antiulcer activity of BPAE was evaluated by absolute ethanol- and indomethacin-induced gastric ulcer, and pyloric ligation models. Acute toxicity was also carried out.

Results

BPAE, at the dose of 5000 mg/kg, did not cause any signs of toxicity to rats when given orally. Oral administration of BPAE exhibited antiulcer activity (p < 0.05) in all models used. However, the dose-dependent activity was observed only in the absolute ethanol-induced gastric ulcer model. Histological studies supported the observed antiulcer activity of BPAE. In pyloric ligation assay, BPAE increased the gastric wall mucus secretion.

Conclusions

The BPAE exhibits antiulcer activity, which could be due to the presence of saponins or sugar-free polyphenols, and, thus, confirmed the traditional uses of Bauhinia purpurea in the treatment of ulcers.     

Effect of aqueous extract of the leaves of Acalypha wilkesiana 'Godseffiana' Muell Arg (Euphorbiaceae) on the hematology, plasma biochemistry and ocular indices of oxidative stress in alloxan induced diabetic rats

Ethnopharmacological relevance

The leaves of Acalypha wilkesiana are used in Southern Nigeria for the management of hypertension and diabetes mellitus. In this study, the effect of aqueous extract of the leaves of Acalypha wilkesiana on the hematology, plasma biochemistry and ocular indices of oxidative stress was investigated in alloxan induced diabetic rats.

Methodology

Diabetes mellitus was induced by injection of alloxan (80 mg/kg body weight), via the tail vein. The extract was administered orally at 100, 200 and 300 mg/kg (both to normal and diabetic rats), and metformin at 50 mg/kg.

Results

On gas chromatographic analysis of the extract, twenty nine known flavonoids were detected, consisting mainly of 29.77% apigenin, 14.97% quercetin, 11.12% naringenin, 10.62% kaempferol, 9.05% (−)-epicatechin and 4.04% (+)-catechin. Tannic acid and β-sitosterol were also detected. Compared to test control, the treatment lowered (significantly, P < 0.05) plasma glucose, triglyceride, conjugated bilirubin levels, atherogenic index of plasma, plasma alanine transaminase activity, total protein and total bilirubin, aspartate transaminase activity and unconjugated bilirubin, plasma urea, blood urea nitrogen and ocular malondialdehyde contents, lymphocyte and monocyte counts, and not significantly, plasma very low density lipoprotein cholesterol, but increased (significantly, P < 0.05) plasma calcium contents, total white cell and platelet counts, mean cell volume and ocular ascorbic acid content, and (though not significantly) plasma high density lipoprotein cholesterol level, red cell and neutrophil counts.

Conclusions

This study showed that the extract was hypoglycemic, positively affected the hemopoietic system and integrity and function (dose dependently) of the liver and kidney of the diabetic rats; improved the lipid profile and had no deleterious effect on red cell morphology. It also protected against oxidative stress in ocular tissues. This study also revealed the presence of pharmacologically active compounds in the leaf extract. All of these highlights the cardioprotective potential of the leaves of Acalypha wilkesiana and support its use in traditional health practices for the management of diabetes mellitus.     

Antinociceptive and antiinflammatory activities of Adiantum latifolium Lam.: Evidence for a role of IL-1β inhibition

Aim of study

Adiantum, one of the most widely distributed genera of the family Pteridaceae, is employed in folk medicine worldwide. Adiantum latifolium Lam. has been used in Latin American traditional medicine as anxiolytic, analgesic and antiinflammatory. The present study investigates the antinociceptive and antiinflammatory properties of the methanolic extract of Adiantum latifolium (MEA) in animal models of pain and inflammation to confirm its medicinal use.

Material and methods

The antinociceptive and antiinflammatory activities of MEA were evaluated using the writhing, formalin, and tail-flick tests, carrageenan-induced paw edema and arachidonic acid-induced ear edema. Mice motor performance was evaluated in the rota rod test and the acute toxicity evaluated over 14 days.

Results

Intraperitoneal (1-100 mg/kg) or oral (100-400 mg/kg) administration of MEA produced a dose-related inhibition of acetic acid-induced writhing in mouse. Furthermore, treatment with MEA (100 mg/kg) inhibited both the early and late phases of formalin-induced hypernociception. In contrast, MEA (100 mg/kg/IP) did not prevent the thermal nociception in the tail-flick test. In addition, MEA (100 and 200 mg/kg/IP) inhibited important events related to the inflammatory response induced by carrageenan or arachidonic acid, namely local edema and increase in tissue interleukin-1β levels. MEA (300 mg/kg/IP)-treated mice did not show any motor performance alterations. Over the study period of 14 days, there were no deaths or toxic signs recorded in the group of mice given 1000 mg/kg of MEA.

Conclusion

The results demonstrate that Adiantum latifolium has antinociceptive and antiinflammatory activities, acting through the inhibition of IL-1β production.     

Momordica charantia extract on insulin resistance and the skeletal muscle GLUT4 protein in fructose-fed rats

Aim of the study

We investigated the preventive effect of Momordica charantia Linn. (Cucurbitaceae) fruit, commonly known as bitter melon, on hyperglycemia and insulin resistance in rats fed with a fructose-enriched diet.

Materials and methods

First, rats were divided randomly into two groups: the control group was fed with control diet, whereas the experimental group was fed with a 60% high-fructose diet for 8 weeks. After the first 6 weeks, the fructose-treated rats were further subdivided into six groups and were orally fed with or without Momordica charantia L. or rosiglitazone (ROS) for 2 weeks while rats were still on fructose diet.

Results

We demonstrated that bitter melon was effective in ameliorating the fructose diet-induced hyperglycemia, hyperleptinemia, hyperinsulinemia, and hypertriglyceridemia as well as in decreasing the levels of free fatty acid (FFA) (P < 0.001, P < 0.05, P < 0.05, P < 0.05, P < 0.05, respectively). Bitter melon reversed fructose diet-induced hypoadiponectinemia (P < 0.05), which provides a therapeutic advantage to insulin resistance in improving insulin sensitivity. Additionally, bitter melon decreased the weights of epididymal (P < 0.05) and retroperitoneal white adipose tissue (WAT) (P < 0.05). Bitter melon increased the expression of peroxisome proliferator-activated receptor γ (PPARγ) in white adipose tissue (WAT). Conversely, bitter melon decreased the expression of leptin in WAT. Furthermore, we demonstrate that bitter melon significantly increases the mRNA expression and protein of glucose transporter 4 (GLUT4) in skeletal muscle.

Conclusions

This study demonstrates, for the first time, the beneficial effects of two different extracts of bitter melon on insulin resistance in rats fed a high-fructose diet thereby producing evidence of the role of changes in expression of PPARγ and GLUT4.     

Wound healing activity of Glycosmis arborea leaf extract in rats

Ethnopharmacological relevance

Glycosmis arborea Roxb, syn. Glycosmis pentaphylla Retz, (Rutacea) is a shrub found all over India, have been used for the healing of wounds of livestock in Indian folk medicine.

Aim of the study

The present study provides a scientific evaluation for the wound healing potential of ethanolic extract of Glycosmis arborea leaves.

Methods and materials

Excision and incision wounds were inflicted upon four groups containing six rats each. Group-1 was assigned as control (ointment base), Group-2 and Group-3 were treated with 5 and 10% EtOH extract ointment. Group-4 was treated with standard Nitrofurazone (0.2%) ointment. The parameters observed were percentage of wound contraction, epithelization period, tensile strength, hydroxyproline content. Ethanolic extract of Glycosmis arborea leaves was given orally at a dose of 200, 400 mg/kg/day in dead space wound model.

Results

Topical application of Glycosmis arborea ointment (10%) in excision wound model significantly (P < 0.05) increased the percentage of wound contraction (96.91%) compared with control (60.27%) and decreased the epithelization time. The tensile strength significantly (P < 0.05) increased in Group-3 at 560.33 ± 6.48 g when compared to control at 319.17 ± 6.16 g. Rats treated with Glycosmis arborea extract (400 mg/kg) showed significant (P < 0.05) increase in hydroxyproline content at 54.94 ± 0.96 mg/g when compared with control at 30.77 ± 1.13 mg/g.

Conclusion

The ethanolic extract of Glycosmis arborea facilitated wound healing significantly, corroborating the folk medicinal use of this plant.     

Antidiabetic effect of Symplocos cochinchinensis (Lour.) S. Moore. in type 2 diabetic rats

Aim

Symplocos cochinchinensis (Lour.) S. Moore. is used in Indian system of traditional medicine to treat diabetes mellitus. The present study aims to investigate the antidiabetic efficacy of the hexane extract of Symplocos cochinchinensis leaves in high fat diet-low streptozotocin (STZ) induced type 2 diabetic rats.

Materials and methods

The doses for the study were fixed based on Irwin test. The hypoglycemic effect of the hexane extract of Symplocos cochinchinensis leaves were studied in normal rats. Oral glucose and insulin tolerance tests were carried out. The antihyperglycemic effect of the hexane extract at 250 and 500 mg/kg was studied in high fat diet-low STZ induced type 2 diabetic rats for 28 days.

Results

The extracts showed no adverse effects up to 5 g/kg concentration. In hypoglycemic study, after treatment with hexane extract at 250 and 500 mg/kg the blood glucose was mildly reduced. In oral glucose tolerance test, the treatment with the hexane extract at 250 and 500 mg/kg showed a highly significant reduction of 12.07% and 23.58% in plasma glucose levels, respectively 30 min after glucose load. The insulin tolerance test also showed improved insulin sensitivity after 60 min of insulin treatment. In high fat diet-low STZ induced type 2 diabetic rats, after 28 days treatment with the hexane extract at 250 and 500 mg/kg reduced the plasma glucose level by 17.04% and 42.10%, respectively. A significant reduction in plasma insulin, plasma and hepatic total cholesterol (TC), triglycerides (TG) and free fatty acids (FFA) and a significant increase in liver glycogen were observed in treated diabetic rats.

Conclusion

This study demonstrated the potential antidiabetic property of hexane extract of Symplocos cochinchinensis leaves on type 2 diabetes mellitus, thus justifying its traditional usage.     

Acute and subchronic oral toxicity studies of Nelumbo nucifera stamens extract in rats

Ethnopharmacological relevance

Since the use of Nelumbo nucifera stamens in herbal medicines as well as in cosmetic products are highly prevalent in Thailand and increasing worldwide, acute and subchronic toxicity studies to confirm the safe use of Nelumbo nucifera stamens are warranted.

Aim of the study

Acute and subchronic oral toxicity studies of Nelumbo nucifera stamens extract in rats were performed in the present study in order to evaluate its safety.

Materials and methods

In acute toxicity study, Nelumbo nucifera stamens extract was administered by oral gavage to Sprague-Dawley rats (5 males and 5 females) at a dose of 5000 mg/kg. In subchronic toxicity study, the extract at doses of 50, 100, and 200 mg/kg/day were given orally to groups of rats (6 rats/dose/sex) for 90 consecutive days.

Results

The extract at a dose of 5000 mg/kg produced no treatment-related signs of toxicity or mortality in any of the animals tested during 14 days of the study. In the repeated dose 90-day oral toxicity study, there was no significant difference in body weight between the control and all treatment groups with the exception of the body weight of the female group treated with 200 mg/kg/day of the extract which was statistically significantly less than that of its control counterpart on day 90 but the percent weight changes of both groups were almost similar. Some statistically significant differences in hematological and biochemical parameters as well as in some internal organ weights of both male and female rats treated with the extract at the highest dose were observed. However, no abnormality of internal organs was observed in both gross and histopathological examinations.

Conclusions

These results suggest that the oral lethal dose of Nelumbo nucifera stamens extract for male and female rats is in excess of 5000 mg/kg and the no-observed-adverse-effect level (NOAEL) of the extract for both male and female rats is considered to be 200 mg/kg/day.     

Antidepressant effect of Valeriana wallichii patchouli alcohol chemotype in mice: Behavioural and biochemical evidence

Ethnopharmacological relevance

Valeriana wallichii DC, an ayurvedic traditional medicine has now been shown to exist chemically as three distinct chemotypes. The study aimed to investigate the antidepressant effect of dichloromethane extract of Valeriana wallichii patchouli alcohol chemotype.

Materials and methods

Antidepressant effect of dichloromethane extract of Valeriana wallichii (10, 20 and 40 mg/kg, p.o.) using forced swim test, was determined in both acute and chronic study. The neurotransmitter levels were estimated in mouse forebrain after two weeks of dosing.

Results

Single administration of extract (40 mg/kg) significantly inhibited the immobility period in mice (p < 0.05). Similarly, chronic administration of extract (20 and 40 mg/kg) significantly reduced the immobility period and significantly increased the levels of norepinephrine and dopamine in mouse forebrain (p < 0.05).

Conclusions

The extract demonstrated antidepressant effect and significantly increased the norepinephrine and dopamine levels in forebrain.     

Evaluation of safety of the herbal formula Ojeok-san: Acute and sub-chronic toxicity studies in rats

Aim of the study

Ojeok-san (OJS; wuji powder in China and goshaku-san in Japan), a widely used herbal formula in traditional Korean medicine and Japanese herbal medicine (Kampo medicine), has been used to treat common cold and illnesses including fatigue and gastrointestinal disorders, but there is very little information on its safety. To provide information on the safety of OJS, we evaluated its acute and sub-chronic toxicity in rats.

Materials and methods

The single and sub-chronic toxicity of OJS was examined using male and female Sprague-Dawley rats. The rats were treated with the OJS extract orally at the highest dose level of 2000 mg/kg/day body weight. After single administration, signs of toxicity were observed every hour for the first 6 h and every day for two weeks. In the sub-chronic toxicity study, OJS was administered for 13 weeks. Mortality, clinical signs, body weight changes, food and water consumption, ophthalmologic findings, urinalysis, hematological and biochemical parameters, gross findings, organ weights and histological markers were monitored during the study period.

Results

We found no mortality and no abnormality in clinical signs, body weight, and necropsy findings for any of the animals in the acute and sub-chronic toxicity study following oral administration of OJS.

Conclusion

OJS may not have any single dose toxicity. The lethal dose with a 50% mortality rate (LD₅₀) was over 2000 mg/kg. The no-observed adverse effects level (NOAEL) was considered to be 2000 and 1000 mg/kg/day for male and female rats, respectively.     

Permeability of rosmarinic acid in Prunella vulgaris and ursolic acid in Salvia officinalis extracts across Caco-2 cell monolayers

Ethnopharmacological relevance

Rosmarinic acid (RA), a caffeic acid-related compound found in high concentrations in Prunella vulgaris (self-heal), and ursolic acid (UA), a pentacyclic triterpene acid concentrated in Salvia officinalis (sage), have been traditionally used to treat inflammation in the mouth, and may also be beneficial for gastrointestinal health in general.

Aim of the study

To investigate the permeabilities of RA and UA as pure compounds and in Prunella vulgaris and Salvia officinalis ethanol extracts across human intestinal epithelial Caco-2 cell monolayers.

Materials and methods

The permeabilities and phase II biotransformation of RA and UA as pure compounds and in herbal extracts were compared using Caco-2 cells with HPLC detection.

Results

The apparent permeability coefficient (P_app) for RA and RA in Prunella vulgaris extracts was 0.2 ± 0.05 × 10⁻⁶ cm/s, significantly increased to 0.9 ± 0.2 × 10⁻⁶ cm/s after β-glucuronidase/sulfatase treatment. P_app for UA and UA in Salvia officinalis extract was 2.7 ± 0.3 × 10⁻⁶ cm/s and 2.3 ± 0.5 × 10⁻⁶ cm/s before and after β-glucuronidase/sulfatase treatment, respectively. Neither compound was affected in permeability by the herbal extract matrix.

Conclusion

RA and UA in herbal extracts had similar uptake as that found using the pure compounds, which may simplify the prediction of compound efficacy, but the apparent lack of intestinal glucuronidation/sulfation of UA is likely to further enhance the bioavailability of that compound compared with RA.     

Antidiabetic activity of alcoholic stem extract of Nervilia plicata in streptozotocin-nicotinamide induced type 2 diabetic rats

Ethnopharmacological relevance

Nervilia plicata (Orchidaceae) has long been used in the antidiabetic medicinal preparations of traditional healers of Wayanad (Kerala), but recuperative potential of the plant was remained undefined. We demonstrated the regenerative potential of the plant extract on kidney affected by type 2 diabetes besides lowering blood glucose.

Aim of the study

The aim of the current study was to investigate the recuperative and regenerative potential of alcoholic stem extract of Nervilia plicata on streptozotocin-nicotinamide induced type 2 diabetic models.

Materials and methods

Non insulin dependent diabetes mellitus (NIDDM) was induced in overnight fasted rats by intramuscular injection (IMI) of 60 mg/kg STZ and 120 mg/kg of nicotinamide after 5 min interval. Blood glucose was assessed by a glucometer, serum urea and creatinine levels were determined by diacetylmonooxime method and Jaffe reaction respectively. Kidney sections were taken and stained with Masson's tri-dye and Periodic Acid Schiff (PAS) and examined for structural changes. Also lipid peroxidation product (LPP) levels were determined as thio barbituric acid reactive substance levels (TBARS) method.

Results

On administration of 5 mg/kg of plant extract, blood glucose levels of the NIDDM rats showed 62.00 and 76.29% decrease in the blood glucose levels on day 0 and day 30 respectively. Damages caused to the kidney tissue were negligible or not seen. Serum urea and creatinine levels showed 61.49 and 70.96% decrease on day 30. LPP levels of kidney and pancreas showed 70.58 and 77.41% decrease respectively.

Conclusion

These results demonstrate significant antidiabetic and regenerative potential of the Nervilia plicata, justifying the use of plant in the indigenous system of medicine. Isolation and characterisation of the compound(s) playing pivotal role in the cure would open new vistas in the therapy of type 2 diabetes.     

Antinociceptive and gastroprotective actions of ethanolic extract from Pluchea sagittalis (Lam.) Cabrera

Ethnopharmacological relevance

Pluchea sagittalis, an herbaceous plant widely distributed in South America, is used in folk medicine for the treatment of digestive diseases and inflammation.

Aim of the study

This study was designed to investigate the antinociceptive and gastroprotective effects of the ethanolic extract (EE) of aerial parts from Pluchea sagittalis in rodents.

Materials and methods

The antinociceptive effects of EE was evaluated in mice after oral administration in chemical tests (acetic-acid, glutamate and formalin) or by biting behavior following intrathecal administration of cytokines such as interleukin-1beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) in mice. Furthermore, rats were treated with EE and subsequently exposed to acute gastric lesions induced by 80% ethanol. Afterwards the gastric lesion extension and the mucus levels of gastric mucosa were measured.

Results

The oral administration of EE showed a dose-dependent inhibition of acetic acid-induced abdominal constrictions and glutamate-induced pain in mice, with ID₅₀ values of 624.0 (523.0-746.0) mg/kg and 368.0 (216.0-628.0) mg/kg, respectively. In the formalin test, the EE also produced significant inhibition of the inflammatory phase, with an ID₅₀ value of 411.0 (183.0-721.0) mg/kg; however, it was ineffective in the neurogenic phase caused by formalin. In addition, oral treatment with EE caused a significant inhibition of biting behavior induced by i.t. injection of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). The antinociception caused by the EE (300 mg/kg, p.o.) was not reversed by naloxone (1 mg/kg, i.p.) when assessed in the acetic acid writhing test. The EE (300-1000 mg/kg, p.o.) did not affect the motor coordination of animals in an open-field model. Oral treatment with the EE protected rats against gastric lesions induced by ethanol, with an ID₅₀ value of 55.0 (46.6-64.9) mg/kg, and increased the mucus levels of gastric mucosa to levels found in the non-lesioned group.

Conclusions

The mechanism by which the extract produced antinociception still remains unclear, but this effect seems to be primarily related to the modulation or inhibition of the action of pro-inflammatory mediators. Furthermore, these data support, at least in part, the ethnomedical use of Pluchea sagittalis.     

Prevention of the progression of adjuvant induced arthritis by oral supplementation of Indian fresh water mussel (Lamellidens marginalis) aqueous extract in experimental rats

Aim of this study

Mussel is well accepted as food all over India. Beside for its nutritive value, people residing in Kosi river basin, Bihar, India, consume a preparation of soup, made from the footpad of molluscan species, with the belief that it gives relief from signs and symptoms of joint pain and related problems. This study was designed to explore the preventive activity of Indian fresh water mussel (Lamellidens marginalis) aqueous extract oral supplementation in experimental arthritis model.

Materials and methods

Arthritis was induced in male albino rats by intradermal injection of Freund's complete adjuvant in right hind footpad. Lamellidens marginalis extract (LME1, 500 mg/kg/day and LME2, 1 g/kg/day) peroral supplementation started from the 1st day after adjuvant injection and was continued for the subsequent 13 days. Severity of arthritis was evaluated from paw diameter, ankle diameter, paw weight, urinary hydroxyproline, glucosamine level, serum interleukin-1β, IL6, IL10, CINC1, TNFα level, lysosomal enzyme levels and from histopathological assessment.

Results

Lamellidens marginalis extract supplementation significantly (p < 0.05) decreased paw diameter, ankle diameter, and paw weight in treated groups (LME1, 500 mg/kg/day and LME2, 1 g/kg/day) as compared with arthritic group. Urinary hydroxyproline, glucosamine level, serum IL1β, IL6, CINC1, TNFα, IL10 and lysosomal enzyme levels were restored significantly (p < 0.05) in treated groups (LME1, 500 mg/kg/day and LME2, 1 g/kg/day) as compared to arthritic group. Synovial membrane damage and neutrophil infiltration in histopathological examination was restored significantly by LME supplementation as compared to arthritic group.

Conclusions

Thus, it might be concluded that experimental animals supplemented with Lamellidens marginalis extract were protected against the severity of disease progression in adjuvant induced arthritis.