Evaluation of hepatoprotective activity of aerial parts of Tephrosia purpurea L. and stem bark of Tecomella undulata

Ethnopharmacological relevance

The aerial parts of Tephrosia purpurea (L.) pers. (Fabaceae) and stem bark of Tecomella undulata seem. (Bignoniaceae) are used for liver disorders in the traditional system of medicine.

Aim of the study

To evaluate the hepatoprotective activity of aerial parts of Tephrosia purpurea and stem bark of Tecomella undulata against thioacetamide-induced hepatotoxicity.

Materials and methods

Hepatotoxicity was induced in albino rats of either sex by subcutaneous injection of thioacetamide. Aqueous–ethanolic extract of aerial parts of Tephrosia purpurea (100, 300 and 500 mg/kg/day and ethanolic extract of stem bark of Tecomella undulata (200, 500 and 1000 mg/kg/day were evaluated.

Results

Oral administration of Tephrosia purpurea at 500 mg/kg and Tecomella undulata at 1000 mg/kg resulted in a significant reduction in serum aspartate aminotransaminase (35% and 31%, respectively), alanine aminotransaminase (50% and 42%, respectively), gamma glutamyl transpeptidase (56% and 49%, respectively), alkaline phosphatase (46% and 37%, respectively), total bilirubin (61% and 48%, respectively) and liver MDA levels (65% and 50%, respectively), and significant improvement in liver glutathione (73% and 68%, respectively) when compared with thioacetamide damaged rats. Histology of the liver sections of the animals treated with the extracts also showed dose-dependent reduction of necrosis.

Conclusions

The present study demonstrates the hepatoprotective activity of the aerial parts of Tephrosia purpurea and stem bark of Tecomella undulata against thioacetamide-induced hepatotoxicity.     

Scientific evidence for traditional claim of anti-obesity activity of Tecomella undulata bark

Ethnopharmacological relevance

The bark of Tecomella undulata is traditionally claimed in the treatment of various disease ailments including obesity and cancer. Till now there are no studies about anti-obesity activity of Tecomella undulata bark.

Aim of the study

The present study was aimed to establish a scientific evidence for anti-obesity efficiency of ethyl acetate extract of Tecomella undulata bark (EATUB). Further to standardize the active fractions of EATUB using different biomarkers.

Materials and methods

We investigated activity of EATUB fractions (F1–F7) using 3T3-L1 fibroblasts. Further, F1-mediated effects were characterized by determining mRNA and protein levels of SIRT1, one of the key targets for the treatment of obesity, using semi-quantitative RT-PCR (sqRT-PCR) and western blot analysis. The consequences of modulation of SIRT1 on mRNA and protein levels of various adipogenesis mediators like PPARγ, C/EBPα, E2F1, leptin, adiponectin and LPL were also studied. In vivo studies were performed using High Fat Diet (HFD) obese mice.

Results

Our data showed that compared to controls, preadipocytes and adipocytes incubated with F1 exhibited a significant decrease in adipogenesis and lipogenesis. In addition, sqRT-PCR and western blot analysis showed significant increase in SIRT1 and adiponectin levels and decrease in PPARγ, C/EBPα, E2F1, leptin and LPL levels in preadipocytes and adipocytes. In vivo studies of F1 in HFD induced obese mice showed significant improvement in lipid profile and glucose levels. The bioactive fraction (F1) was determined to possess 4.95% of ferulic acid.

Conclusion

Thus, our findings signified the beneficial effects of Tecomella undulata bark in pharmacologic interventions related to obesity and metabolic disorders. Ferulic acid and rutin are being reported and quantified for the first time from the bark of Tecomella undulata.     

Antiproliferative activity and standardization of Tecomella undulata bark extract on K562 cells

Ethnopharmacological relevance

The bark of Tecomella undulata is primarily used in the treatment of syphilis, painful swellings and cancer by traditional healers. Also, it is claimed to be useful in treating urinary discharges, enlargement of spleen, leucorrhoea, leukoderma, tumors, liver disorders, gonorrhea, gout and promotes wound healing in Indian traditional system of medicine.

Aim

To establish a scientific validation for the antitumor effects of Tecomella undulata bark and explore the mechanistic pathway in chronic myeloid leukemia cell line, K562. The study was further extended to standardize the extract using quercetin as biomarker.

Methods

Induction of apoptosis by chloroform extract of Tecomella undulata bark (CTUB) was determined by MTT, Annexin V and caspase activation assays. The cell cycle analysis was done by flow cytometer and nuclear staining by DAPI. The standardization of the extract was performed through reverse phase-HPLC method under PDA detection.

Result

Results clearly showed the induction of apoptosis by CTUB in K562 cells. The effect was found to be dose dependent, having IC₅₀ of 30 μg/ml with activation of FAS, FADD, caspase 8, caspase 3/7 and fragmentation of DNA. The bioactive CTUB was determined to possess 0.03% (w/w) of quercetin.

Conclusion

The investigation clearly demonstrated the potential antitumor effect of CTUB, thereby validating the traditional claim. Quercetin, known to have anticancer activity is being reported and quantified for the first time from the bark of Tecomella undulata.     

Hepatoprotective activity of ethanolic extracts of bark of Zanthoxylum armatum DC in CCl4 induced hepatic damage in rats

Aim of the study

Zanthoxylum armatum DC is described as a hepatoprotective in Ayurveda, the Indian system of medicine. However, there is no scientific basis or reports in the modern literature regarding its usefulness as a hepatoprotective agent. The present study was carried out to evaluate the hepatoprotective activity of ethanolic extract of bark of Zanthoxylum armatum DC in CCl₄ induced hepatotoxicity in male Wistar rats.

Materials and methods

Ethanolic extracts at doses of 100, 200, and 400 mg/kg were administered orally once daily for 7 days. The hepatoprotective activity was assessed using various biochemical parameters like alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, serum bilirubin, total protein and serum antioxidant enzymes along with histopathological studies of liver tissue.

Results

The substantially elevated serum enzymatic levels of serum transaminases, alkaline phosphatase and total bilirubin were significantly restored towards normalization by the extracts. Bark extracts significantly increased the levels of antioxidant enzymes: superoxide dismutase, catalase and glutathione. Phytochemical analysis revealed presence of isoquinoline alkaloid, berberine, as well as flavonoids and phenolic compounds, which have been known for their hepatoprotective activities.

Conclusions

Zanthoxylum armatum DC possesses significant protective effect against hepatotoxicity induced by CCl₄ which may be attributed to the individual or combined action of phytoconstituents present in it.     

Hepatoprotective effect of Trichosanthes cucumerina Var cucumerina L. on carbon tetrachloride induced liver damage in rats

Ethnopharmacological relevance

Different parts of the plant Trichosanthes cucumerina Var cucumerina L. (cucurbitaceae) are used to treat liver disorders, traditionally. It is one among the constituents in various Ayurvedic formulations used for the treatment of liver disorders and other diseases.

Aims of study

The aim of the present study is to evaluate the protective effect of Trichosanthes cucumerina against experimentally induced liver injury.

Materials and methods

The methanolic extract of whole plant of Trichosanthes cucumerina (TCME) was evaluated for the hepatoprotective activity against carbon tetrachloride (CCl₄) induced hepatotoxicity in rats. Various biochemical parameters like alanine amino transferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP), total bilirubin (TB), total protein (TP) and albumin (ALB) levels were estimated in serum as well as the glutathione (GSH) and malondialdehyde (MDA) levels in the liver were determined. Histopathological changes in the liver of different groups were also studied.

Results

The pre-treatment of TCME at dose levels of 250 and 500 mg/kg b.w.p.o. had controlled the raise of AST, ALT, ALP, TB and MDA levels and the effects were comparable with standard drug (silymarin 100 mg/kg b.w.p.o.). The GSH, TP and ALB levels were significantly increased in the animals received pre-treatment of the extract. The animals received pre-treatment of the extract shown decreased necrotic zones and hepatocellular degeneration when compared to the liver exposed to CCl₄ intoxication alone. Thus the histopathalogical studies also supported the protective effect of the extract.

Conclusion

This study demonstrates the hepatoprotective activity of Trichosanthes cucumerina and thus scientifically supports the usage of this plant in various Ayurvedic preparations and traditional medicine for treatment of liver disorders.     

Hepatoprotective action of Orthosiphon diffusus (Benth.) methanol active fraction through antioxidant mechanisms: An in vivo and in vitro evaluation

Ethnopharmacological relevance

Preparations of Orthosiphon diffusus (Benth.) have been used by folk medicinal practitioners in the Western Ghats of India for treating inflammation, hepatitis and jaundice for many years and their effectiveness is widely acclaimed among the tribal communities.

Aim of the study

To evaluate the mechanisms behind the antioxidant and hepatoprotective potential of Orthosiphon diffusus methanol active fraction (MAF) using in vivo (rat) and in vitro (cell culture) models.

Materials and methods

Neutralization of CCl₄-induced hepatotoxicity by MAF was evaluated in rats. Towards this, serum levels of hepatic injury markers (lactate dehydrogenase and alkaline phosphatase), antioxidant enzymes in the liver homogenates, and histological examination were performed. In in vitro studies, mechanisms of neutralization of H₂O₂-induced toxicity by MAF using MTT, Comet assay and up-regulation of antioxidant enzymes at genetic level (RT-PCR) was performed in HepG2 cells.

Results

Rats pre-treated with Orthosiphon diffusus MAF demonstrated significantly reduced levels of serum LDH (1.3-fold, p<0.05) and ALP (1.6-fold, p<0.05). Similarly, multiple dose MAF administration demonstrated significantly enhanced levels (p<0.05) of antioxidant enzymes in the liver homogenates. Histological analysis revealed complete neutralization of CCl₄-induced liver injury by the extract. The in vitro studies demonstrated that, pre-treatment of MAF effectively prevented H₂O₂-induced oxidative stress, genotoxicity and significantly enhanced (~6-fold, p<0.01) expression of genes for antioxidant enzymes.

Conclusions

Orthosiphon diffusus MAF demonstrated significant hepatoprotection against CCl₄-induced hepatotoxicity by antioxidant mechanisms comparable to silymarin. H₂O₂-induced oxidative stress was completely neutralized by MAF through enhanced expression of genes for antioxidant enzymes. Therefore, this study validates the use of Orthosiphon diffusus by folk medicinal practitioners in India. Further, MAF of Orthosiphon diffusus can serve as a strong candidate for the development of herbal hepatoprotective agents.     

Hypoglycaemic activity of four plant extracts traditionally used in South Africa for diabetes

Aim

To validate plant species for hypoglycaemic activity.

Materials and methods

Four plants were investigated for hypoglycaemic activity by evaluating inhibiting effects on carbohydrate-hydrolising enzymes: α-glucosidase and α-amylase. Acetone plant extracts were screened against C2C12 myocytes, 3T3-L1 preadipocytes and Chang liver cells by measuring glucose uptake. Cytotoxicity was done in preadipocytes and hepatocytes.

Results

Extract of Euclea undulata rootbark exhibited highest activity, displaying a glucose uptake of 162.2% by Chang liver cells at 50 μg/ml. An inhibition concentration of 50% for Euclea undulata was found to be 49.95 μg/ml for α-glucosidase and 2.8 μg/ml for α-amylase. No cytotoxicity was recorded for Euclea undulata, while Schkuhria pinnata and Elaeodendron transvaalense exhibited cytotoxicity at 12.5 μg/ml. α-Glucosidase and α-amylase assays showed inhibitory activity on enzymes for three plant extracts.

Conclusion

Euclea undulata, Schkuhria pinnata and Elaeodendron transvaalense showed in vitro hypoglycaemic activity. Schkuhria pinnata and Elaeodendron transvaalense indicated cytotoxicity on 3T3-L1 preadipocytes and Chang liver cells. Euclea undulata, Pteronia divaricata and Elaeodendron transvaalense inhibited α-glucosidase and α-amylase enzymes.

Ethnopharmacological relevance

Screening of plant extracts scientifically validated traditional use of Euclea undulata for treatment of diabetes. Cytotoxicity results revealed that acetone extracts of Schkuhria pinnata and Elaeodendron transvaalense are toxic and raise concern for chronic use.     

Antiparasitic compounds from Cornus florida L. with activities against Plasmodium falciparum and Leishmania tarentolae

Aim of the study

The objective of this study was to identify the antiplasmodial constituents from the bark of Cornus florida L., a plant traditionally used in North America for the treatment of malaria.

Methods and materials

Dried and powdered bark was extracted with 95% ethanol. The resultant extract was subjected to in vitro antiplasmodial-guided fractionation against Plasmodium falciparum (D10 strain). Antiplasmodial IC₅₀ values were calculated for pure compounds. Compounds were also assayed against Leishmania tarentolae, and rat skeletal myoblast L6 cells to assess antileishmanial activity and cytotoxicity, respectively.

Results

Antiplasmodial-guided fractionation afforded 8 compounds: betulinic acid (1), ursolic acid (2), β-sitosterol (3), ergosta-4,6,8,22-tetraene-3-one (4), 3β-O-acetyl betulinic acid (5), 3-epideoxyflindissol (6), 3β-O-cis-coumaroyl betulinic acid (7), 3β-O-trans-coumaroyl betulinic acid (8), of which, (6) is for the first time here isolated from a natural product and (4), (7) and (8) are reported for the first time from this genus. In vitro IC₅₀ values against P. falciparum for (4) (61.0 μM) (6) (128.0 μM), (7) (10.4 μM), (8) (15.3 μM) are reported for the first time. Antileishmanial IC₅₀ values are reported here for the first time for (4) (11.5 μM), (6) (1.8 μM), (7) (8.3 μM) and (8) (2.2 μM). Cytotoxicity against L6 cells is reported for all compounds.

Conclusions

The compounds isolated in this study, while displaying moderate in vitro antiplasmodial activity, do not fully support the historical importance of C. florida as an antimalarial remedy in North America. The traditional remedy may exert its well documented effects by mechanisms unrelated to direct antiplasmodial action. While not traditionally used to treat Leishmania, this work shows that several constituents of C. florida possess promising in vitro antileishmanial activity.     

Anti-inflammatory and mutagenic evaluation of medicinal plants used by Venda people against venereal and related diseases

Ethnopharmacology relevance

Inflammation is a major risk factor for various human diseases including venereal diseases, often resulting in treatment complications. Plants have been traditionally used for treatment of many different diseases and have been successfully proven to be an alternative source in treatment of infectious diseases.

Aim of the study

This study was aimed at evaluating the anti-inflammatory activities and the mutagenic properties of 12 medicinal plants used by the Venda people against venereal and related diseases.

Materials and methods

The plants were evaluated for their anti-inflammatory activity against the cyclooxygenase (COX-1 and -2) enzymes and genotoxicity using the Ames test, with and without S9 (metabolic activation) against Salmonella typhimurium tester strain TA98.

Results

DCM and PE extracts of Adansonia digitata bark, Bolusanthus speciosus bark, Pterocarpus angolensis bark and Pappea capensis leaves and EtOH and water extracts of Bolusanthus speciosus stem and Ekebergia capensis bark showed the best anti-inflammatory activity in both COX-1 and -2 assays at 250 μg/ml. These were further evaluated at three other concentrations (31.25, 62.5, and 125 μg/ml) to determine IC₅₀ values. Water extracts of Ekebergia capensis bark showed the best IC₅₀ value towards COX-1. The Ames test revealed that all plant extracts were non-mutagenic towards Salmonella typhimurium strain TA98 except for Elephantorrhiza burkei and Ekebergia capensis that showed weak mutagenicity.

Conclusion

The active plants may offer a new source of chemicals for the effective treatment of anti-inflammatory conditions related to venereal diseases.     

Antioxidant and hepatoprotective activity of Fagonia schweinfurthii (Hadidi) Hadidi extract in carbon tetrachloride induced hepatotoxicity in HepG2 cell line and rats

Ethnopharmacological relevance

The whole plant of Fagonia schweinfurthii (Hadidi) Hadidi (Family: Zygophyllaceae) is used in variety of diseases including hepatic ailments in deserts and dry areas of India.

Aim of the study

To evaluate antioxidant and hepatoprotective activity of ethanolic extract from Fagonia schweinfurthii (Hadidi) Hadidi (FSEE) in carbon tetrachloride (CCl₄) induced hepatotoxicity in HepG2 cell line and rats.

Materials and methods

In vitro antioxidant activity was determined by DPPH, ABTS radicals and hydrogen peroxide methods. In vitro cytotoxicity and hepatoprotective potential of FSEE were evaluated using HepG2 cells. Based on the cytotoxicity assay, FSEE (50, 100, 200 µg/ml) was assessed for hepatoprotective potential against CCl₄ induced toxicity in HepG2 cell line by monitoring cell viability, aspartate aminotransferase (AST), alanine aminotransaminase (ALT), lactate dehydrogenase (LDH) leakage, lipid peroxidation (LPO) and glutathione level (GSH). Further, in vivo hepatoprotective activity of FSEE was evaluated against CCl₄ induced hepatotoxicity in male Wistar albino rats. Rats were pre-treated with FSEE (200 mg, 400 mg kg⁻¹ day⁻¹ p.o.) for 7 days followed by a single dose of CCl₄ (1.0 ml/kg, i.p.) on 8th day. Silymarin was used as positive control. After 24 h of CCl₄ administration, various biochemical parameters like aspartate aminotransferase (AST), alanine aminotransaminase (ALT), alkaline phosphatase (ALP), total bilirubin (TB) and total protein (TP) levels were estimated in serum. The antioxidant parameters like superoxide dismutase (SOD) activity, catalase (CAT) activity, glutathione (GSH) content and malondialdehyde (MDA) level in the liver homogenate were determined. Histopathological changes in the liver of different groups were also studied.

Results

The FSEE possessed strong antioxidant activity in vitro. The results indicated that CCl₄ treatment caused a significant decrease in cell viability. The CCl₄-induced changes in the HepG2 cells were significantly ameliorated by treatment of the FSEE. FSEE significantly prevented CCl₄ induced elevation of AST, ALT, ALP, TB, and CCl₄ induced decrease in total protein in rats. FSEE treated rat liver anti-oxidant parameters (SOD, CAT, MDA and GSH,) were significantly antagonized for the pro-oxidant effect of CCl₄. Histopathological studies also supported the protective effect of FSEE.

Conclusion

The results of this study revealed that FSEE has significant hepatoprotective activity. This effect may be due to the ability of the extract to inhibit lipid peroxidation and increase in the anti-oxidant enzymatic activity.     

Anti-inflammatory intestinal activity of Abarema cochliacarpos (Gomes) Barneby & Grimes in TNBS colitis model

Aim of the study

To assess the anti-inflammatory effect of butanolic fraction of methanolic extract from bark of Abarema cochliacarpos in acute ulcerative colitis model induced by intracolonic administration of trinitrobenzene sulfonic acid (TNBS) in Wistar rats.

Materials and methods

Abarema cochliacarpos (100 and 150 mg/kg/day) was administered by gavage 48, 24 and 1 h prior to the induction of colitis with 10 mg/kg of TNBS and, 24 h later.

Results

Phytochemical studies by mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR) revealed that catechins were a major component into condensate class of tannins. Treatment with Abarema cochliacarpos decreased significantly macroscopic damage as compared with TNBS (p < 0.05). Histological analysis showed that both doses of the extract improved the microscopic structure and preserved some areas of the colonic mucosa structure. In addition, myeloperoxidase activity (MPO), as a marker of neutrophil infiltration, was decreased in a dose-dependent way (p < 0.01 and p < 0.001 respectively), TNF-α level was also diminished with the highest dose of the extract (p < 0.001) and, IL-10 level obtained no significant results. In order to elucidate some of the mechanisms, expression of inducible inflammatory enzymes, such as cyclooxygenase (COX)-2 and nitric oxide synthase (iNOS), were studied showing a significant reduction. Finally, the involvement of c-Jun N-terminal kinase (JNK) signalling demonstrated a reduction in the JNK activation with the highest dose (p < 0.05 vs TNBS).

Conclusions

We have shown for the first time that the extracts obtained from Abarema cochliacarpos bark possess active substances, which exert marked protective effects in acute experimental colitis, confirming and justifying, at least in part, the popular use of this plant to treat gastrointestinal diseases.     

Anti-inflammatory activities of Dictamnus dasycarpus Turcz., root bark on allergic contact dermatitis induced by dinitrofluorobenzene in mice

Ethnopharmacological relevance

The root bark of Dictamnus dasycarpus Turcz. is widely used as a medicinal herb for treatment of skin diseases such as eczema, pruritus and urticaria in China, Japan and Korea.

Materials and methods

We investigated the effects of methanol extract of Dictamnus dasycarpus Turcz., root bark (MEDD) on ear thickness, ear weights, histopathological changes such as hyperplasia, edema, spongiosis and immune cell infiltration and cytokine productions in 1-fluoro-2,4-dinitrofluorobenzene (DNFB)-induced contact dermatitis (CD) mice. We also investigated its effects on degranulation of histamine and β-hexosaminidase and related mechanisms using RBL-2H3 cells.

Results

Topical application of MEDD effectively inhibited enlargement of ear thickness and weight (P<0.05). MEDD treatment also inhibited hyperplasia, edema and spongiosis induced by DNFB. Treatment with 300 μg/ear of MEDD suppressed the increase in IFN-γ and TNF-α levels (P<0.05). In addition, treatment with >50 μg/mL MEDD reduced the level of β-hexosaminidase release, while >100 μg/mL MEDD lowered the level of histamine release in a dose-dependent manner (P<0.05). Finally, MEDD treatment prevented phosphorylation of p38 MAPK induced by phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187 in RBL-2H3 cells.

Conclusions

These data indicate that root bark of Dictamnus dasycarpus Turcz. has the potential for use in the treatment of allergic skin diseases. Furthermore, they suggest that root bark of Dictamnus dasycarpus Turcz. is involved in decreasing degranulation of MCs via inhibition of the p38 MAPK pathway as well as in the inhibition of Th1 skewing reactions.     

Hepatoprotective studies on Sida acuta Burm. f.

Ethnopharmacological relevance

Sida acuta Burm. f. (Malvaceae) is used in Indian traditional medicine to treat liver disorders and is useful in treating nervous and urinary diseases and also disorders of the blood and bile.

Aim of the study

Evaluation of the hepatoprotective properties of the methanolic extract of the root of Sida acuta (SA) and the phytochemical analysis of SA.

Materials and methods

The model of paracetamol-induced hepatotoxicity in Wistar rats, liver histopathological observations, hexobarbitone-induced narcosis and in vitro anti-lipid peroxidation studies were employed to assess the hepatoprotective efficacy of SA. Phytochemical assay of SA was conducted following standard protocols.

Results

Significant hepatoprotective effects were obtained against liver damage induced by paracetamol overdose as evident from decreased serum levels of glutamate pyruvate transaminase, glutamate oxaloacetate transaminase, alkaline phosphatase and bilirubin in the SA treated groups (50, 100, 200 mg/kg) compared to the intoxicated controls. The hepatoprotective effect was further verified by histopathology of the liver. Pretreatment with Sida acuta extract significantly shortened the duration of hexobarbitone-induced narcosis in mice indicating its hepatoprotective potential. Phytochemical studies confirmed the presence of the phenolic compound, ferulic acid in the root of Sida acuta, which accounts for the significant hepatoprotective effects observed in the present study.

Conclusion

The present study thus provides a scientific rationale for the traditional use of this plant in the management of liver disorders.     

Chemopreventive and anti-cancer properties of the aqueous extract of flowers of Butea monosperma

Ethnopharmacological relevance

Butea monosperma (Lam.) (Fabaceae) popularly known as ‘flame of the forest’ has been widely used in the traditional Indian medical system of ‘Ayurveda’ for the treatment of a variety of ailments including liver disorders.

Aim of the study

To evaluate the antioxidative, anti-inflammatory, hepatoprotective and anti-cancer activities of the aqueous extract of Butea monosperma flowers.

Materials and methods

Dried flowers of Butea monosperma were extracted with water. The extract was tested for its anti-proliferative, pro-apoptotic and anti-carcinogenic effects in hepatoma cell lines. The chemopreventive and anti-angiogenic effects of the extract were evaluated by its daily oral administration in a HBV-related X15-myc mouse model of hepatocellular carcinoma (HCC).

Results

Treatment with the aqueous extract inhibited cell proliferation and accumulation of cells in G1 phase. This was accompanied by a marked reduction in the levels of activated Erk1/2 and SAPK/JNK and induction of apoptotic cell death. Oral administration of the extract in transgenic mice conferred hepatoprotection as is evident from normal serum ALT levels and improved liver histopathology and lowered serum VEGF level.

Conclusions

The ability of aqueous extract of Butea monosperma flowers to impose growth arrest and trigger pro-apoptotic death in cell culture strongly correlated with its strong chemopreventive effect in vivo when given orally.     

Hypoglycaemic effects of Mammea africana (Guttiferae) in diabetic rats

Aim of the study

The stem bark of Mammea africana Sabine (Guttiferae) is used in African rain forest to treat various diseases, including diabetes mellitus. We investigated whether Mammea africana extract induced hypoglycaemic activity in rats.

Materials and methods

We tested the effects of acute (5 h) and sub-acute (21 days) oral administrations of the CH₂Cl₂–MeOH stem bark extract of Mammea africana (19–300 mg/kg body weight) on blood glucose levels of normal and streptozotocin (STZ)-induced type 1 diabetic rats. The effects were compared with those of glibenclamide.

Results

Acute administration reduced blood glucose in the diabetic rats only (33.87%, P < 0.01). Sub-acute treatment for 21 days also reduced blood glucose level in diabetic rats (73.29%, P < 0.01). A reduction or stabilization in total serum protein, triglyceride, cholesterol and alanine amino transferase levels was also observed. No effect was observed on body weight loss but food and water intakes were significantly reduced (P < 0.01) in diabetic rats. The maximal anti-diabetic effect was obtained with the dose of 75 mg/kg and was more important than that of glibenclamide.

Conclusion

It can be concluded that extracts of Mammea africana exhibited a significant anti-hyperglycaemic activity and improved the metabolic alterations in STZ-diabetic rats. These results provide a rationale for the use of Mammea africana to treat diabetes mellitus and hypercholesterolemia.     

Aqueous extract of Artemisia capillaris exerts hepatoprotective action in alcohol–pyrazole-fed rat model

Ethnopharmacologic relevance

Artemisia capillaris, also called “InJin” in Korean, has been widely used to treat various hepatic disorders in traditional Oriental medicine.

Aims

The purpose of this study is to evaluate the hepatoprotective effect of Artemisia capillaris (aqueous extract, WAC) on alcoholic liver injury.

Materials and methods

Liver injury was induced by oral administration of 30% alcohol (10 mL/kg, twice per day) plus pyrazole (PRZ, 30 mg/kg) with/without WAC (50, 100 mg/kg, orally once per day) or silymarin (50 mg/kg) for 10 days. The hepatoprotective effects were assessed by observing histopathological changes, hepatic transaminase enzymes, hepatic oxidation and antioxidant parameters, inflammatory cytokines, and alcohol metabolic enzymes in serum and hepatic gene expression level, respectively.

Results

Alcohol–PRZ treatment drastically increased the serum levels of aspartate transaminase (AST), alanine transaminase (ALT), and malondialdehyde (MDA) levels in serum and liver tissues while these changes were significantly ameliorated by WAC administration (p<0.05 or 0.01). The prominent microvesicular steatosis and mild necrosis in hepatic histopathology were induced by alcohol–PRZ treatment, but notably attenuated by WAC administration. Moreover, the alcohol–PRZ treatment-induced depletions of the antioxidant components including glutathione content, total antioxidant capacity (TAC), activities of glutathione peroxidase (GSH-Px), reductase (GSH-Rd), catalase, and superoxide dismutase (SOD) were significantly ameliorated by WAC administration (p<0.05, except GSH-Rd). These results were in accordance with the modulation of NF-E2-related factor (Nrf2) and heme oxygenase-1 (HO-1) gene expression. Alcohol–PRZ treatment increased the levels of tumor necrosis factor-alpha (TNF-α) and transforming growth factor-beta (TGF-β) in hepatic tissues. However they were significantly normalized by WAC administration (p<0.05 or 0.01). In addition, WAC administration significantly attenuated the alterations of aldehyde dehydrogenase (ALDH) level in serum and hepatic gene expressions of ALDH and alcohol dehydrogenase (ADH).

Conclusions

These results support the relevance in clinical use of Artemisia capillaris for alcohol-associated hepatic disorders. The underlying mechanisms may involve both enhancement of antioxidant activities and modulation of proinflammatory cytokines.     

Effect of Laggera alata on hepatocyte damage induced by carbon tetrachloride in vitro and in vivo

Ethnopharmacological relevance

Laggera alata, as a traditional Chinese herbal medicine, has been widely used to ameliorate some ailments associated with inflammation including hepatitis in folk.

Aim of the study

Based on anti-inflammatory activity of total phenolics from Laggera alata (TPLA), to further validate the remarkable curative effect Laggera alata in hepatitis, hepatoprotective effect of TPLA was examined.

Materials and methods

TPLA was prepared and its principle components were quantificationally analyzed. The hepatoprotective effects of TPLA were studied using a CCl₄-induced injury model in primary cultured neonatal rat hepatocytes, and a CCl₄-induced acute and chronic damage model in vivo.

Results

TPLA significantly reduced cellular leakage of hepatocyte aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and improved cell viability in vitro. TPLA markedly decreased the serum AST and ALT levels of the mice, the levels of AST, ALT, total protein, albumin, and sialic acid in rat serum, and the hydroxyproline level in rat liver. Meanwhile, severe hepatic lesions induced by CCl₄ in mice/rats were remarkably improved by the administration of TPLA.

Conclusions

This investigation verifies the hepatoprotective effect of TPLA in vitro/in vivo and clarifies its active components dicaffeoylquinic acids responsible for hepatoprotective potential.     

Treatment with an extract of Terminalia superba Engler & Diels decreases blood pressure and improves endothelial function in spontaneously hypertensive rats

Ethnopharmacological relevance

The stem bark of Terminalia superba (TS) is widely used as a decoction by Cameroonian folk medicine for the treatment of hypertension. The aim of the present study was to evaluate the effect of a chronic treatment with a TS extract on spontaneously hypertensive rats (SHR) with respect to efficacy, biochemical mechanisms and safety.

Materials and methods

Eleven-week-old SHR and normotensive Wistar Kyoto rats (WKY) were daily treated by gavage with a methylene chloride extract of stem bark of Terminalia superba (TMSE, 150 mg/kg) or with the vehicle for 5 weeks. Systolic blood pressure (SBP) was measured weekly using the tail-cuff method. At the end of the treatment period, vascular function was assessed on isolated thoracic rings, urinary 8-iso-PGF_2α levels were measured and cytochrome P-450 3A (CYP 3A) activity was evaluated in liver microsomes.

Results

TMSE reduced SBP (P<0.001) in SHR but not in WKY rats. In SHR, the vasorelaxant response to acetylcholine was significantly improved by TMSE as a result of increased nitric oxide synthase (NO) activity and decreased superoxide anion production. In addition, TMSE reduced the vasoconstrictive effect of phenylephrine and improved the sensitivity of smooth muscle cells to NO. TMSE dramatically decreased 8-iso-PGF_2α levels in SHR. By contrast, TMSE did not affect all these parameters in WKY rats. Neither diuresis nor the hepatic CYP 3A activity was modified in both animal groups.

Conclusions

This study demonstrated that Terminalia superba has a potent antihypertensive activity in SHR which is partly due to endothelium-dependent and endothelium-independent effects as well as decreased oxidative stress. The data also provide evidence for the lack of herb-drug interaction through hepatic CYP 3A.     

Anti-inflammatory activity of Mitraphylline isolated from Uncaria tomentosa bark

Ethnopharmacological relevance

Uncaria tomentosa (Willd. ex Roem. & Schult.) DC. (Rubiaceae) is widely used by populations living in South America to treat many ailments associated with inflammatory disorders. Mitraphylline was shown to be the major pentacyclic oxindolic alkaloid present in the bark chloroformic extract of this plant. Its activity against cytokines involved in inflammation process was tested in a murine model in vivo.

Materials and methods

Mice received mitraphylline once a day for 3 days at 30 mg/kg/day by oral route. Then, they were subjected to bacterial lipopolysaccharide (LPS) endotoxin (15 mg/kg) and the LPS-induced production of 16 different cytokines was determined by Elisa multiplex. Control group received dexamethasone orally at 2 mg/kg/day. Toxicity on K565 cells and murine peritoneal macrophages, in vitro, at doses up to 100 μM was monitored by XTT-colorimetric assay.

Results and conclusions

For the first time mitraphylline was tested in vivo against a large range of cytokines that play a crucial role in inflammation. Mitraphylline inhibited around 50% of the release of interleukins 1α, 1β, 17, and TNF-α. This activity was similar to dexamethasone. It also reduced almost 40% of the production of interleukin 4 (IL-4) while the corticoid did not. Lastly it did not show any toxicity on K565 cells nor murine macrophages at doses up to 100 μM.     

Antioxidant and hepatoprotective effect of swertiamarin from Enicostemma axillare against d-galactosamine induced acute liver damage in rats

Ethnopharmacological relevance

The whole plant of Enicostemma axillare Raynal (Family: Gentianaceae) is used in variety of diseases in traditional Indian system of medicine including hepatic ailments.

Aim of the study

Swertiamarin isolated from Enicostemma axillare Raynal was evaluated for antioxidant and hepatoprotective activity.

Materials and methods

Swertiamarin was isolated from successive ethyl acetate extract of the plant Enicostemma axillare belongs to the family Gentianaceae. The concentration of swertiamarin was determined by high performance thin layer chromatography (HPTLC). The hepatoprotective and antioxidant activity of swertiamarin (100 and 200 mg/kg body weight) was carried out against d-Galactosamine (d-GalN) (200 mg/kg body weight intraperitoneally i.p.) induced liver injury in rats.

Results

Swertiamarin a secoiridoid glycoside was found to contain a major constituent of the extract. d-GalN caused significant hepatotoxicity by alteration of several hepatic parameters. It also caused significant lipid peroxidation and reduced the levels of antioxidant defense mechanisms. The treatment with swertiamarin at 100 and 200 mg/kg body weight when administered orally for 8 days prior to d-GalN caused a significant restoration of all the altered biochemical parameters due to d-GalN towards the normal, indicating the potent antioxidant and hepatoprotective nature of swertiamarin.

Conclusions

Swertiamarin isolated from Enicostemma axillare possesses significant antioxidant and hepatoprotective properties against d-GalN induced hepatotoxicity given at 100 and 200 mg/kg body weight orally for 8 days, which might be due to its in vitro antioxidant activity.