Hepatoprotection with a chloroform extract of Launaea procumbens against CCl4-induced injuries in rats

Hepatoprotective activity of the ethanolic extract of Morus indica roots from Indian Bodo tribes

The roots of Morus species are well described in the Pharmacopoeia of the People's Republic of China (ChP) for its traditional use in treating liver fibrosis due to its hepatoprotective property. However, little is known about the hepatoprotective effect of the roots of Morus indica L. (RoMi), and the pharmacological mechanism(s) are uncertain due to its intricacy. Therefore, this study evaluates the hepatoprotective activity of the ethanolic extract of RoMi (eRoMi) against the CCl4-induced in-vivo animal model at different dosages (100 and 200 mg/kg BW) in comparison with silymarin as a positive control. The hepatoprotective activity of eRoMi was evaluated by measuring the levels of serum biomarkers, hepatic antioxidant enzymes and was verified by histological studies. Interestingly, 1,2-bis(trimethylsilyl) benzene, 1,4-phenylenebis (trimethylsilane), 2,4,6-cycloheptatriene-1-one, 3,5-bis-trimethylsilyl and α-amyrin were the active components found in eRoMi as detected by GC–MS. Oral administration of eRoMi (200 mg/kg BW) to rats significantly protected serum biochemical parameters (increased ALT, AST, LDH, bilirubin and GGT as well as depletion of antioxidant enzymes and hepatic GSH) and elevation in hepatic lipid peroxidation as compared to CCl4-treated rats. The hematological indices such as erythrocytes, hemoglobin, monocytes and lymphocytes were also normal in eRoMi-treated rats. The histopathological evaluation indicated a significant restoration of liver structure as compared to silymarin. This study is the first scientific validation for the traditional use of eRoMi to understand its hepatoprotective activity.

Chinese medicine in the treatment of autoimmune hepatitis: Progress and future opportunities

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease occurring in individuals of all ages with a higher incidence in females and characterized by hypergammaglobulinemia, elevated serum autoantibodies and histological features of interface hepatitis. AIH pathogenesis remains obscure and still needs in‐depth study, which is likely associated with genetic susceptibility and the loss of immune homeostasis. Steroids alone and in combination with other immunosuppressant agents are the primary choices of AIH treatment in the clinic, whereas, in some cases, severe adverse effects and disease relapse may occur. Chinese medicine used for the treatment of AIH has proven its merits over many years and is well tolerated. To better understand the pathogenesis of AIH and to evaluate the efficacy of novel therapies, several animal models have been generated to recapitulate the immune microenvironment of patients with AIH. In the current review, we summarize recent advances in the study of animal models for AIH and their application in pharmacological research of Chinese medicine‐based therapies and also discuss current limitations. This review aims to provide novel insights into the discovery of Chinese medicine‐originated therapies for AIH using cutting‐edge animal models.

Hepatoprotective activity of the ethanolic extract of Morus indica roots from Indian Bodo tribes

The roots of Morus species are well described in the Pharmacopoeia of the People's Republic of China (ChP) for its traditional use in treating liver fibrosis due to its hepatoprotective property. However, little is known about the hepatoprotective effect of the roots of Morus indica L. (RoMi), and the pharmacological mechanism(s) are uncertain due to its intricacy. Therefore, this study evaluates the hepatoprotective activity of the ethanolic extract of RoMi (eRoMi) against the CCl4-induced in-vivo animal model at different dosages (100 and 200 mg/kg BW) in comparison with silymarin as a positive control. The hepatoprotective activity of eRoMi was evaluated by measuring the levels of serum biomarkers, hepatic antioxidant enzymes and was verified by histological studies. Interestingly, 1,2-bis(trimethylsilyl) benzene, 1,4-phenylenebis (trimethylsilane), 2,4,6-cycloheptatriene-1-one, 3,5-bis-trimethylsilyl and α-amyrin were the active components found in eRoMi as detected by GC–MS. Oral administration of eRoMi (200 mg/kg BW) to rats significantly protected serum biochemical parameters (increased ALT, AST, LDH, bilirubin and GGT as well as depletion of antioxidant enzymes and hepatic GSH) and elevation in hepatic lipid peroxidation as compared to CCl4-treated rats. The hematological indices such as erythrocytes, hemoglobin, monocytes and lymphocytes were also normal in eRoMi-treated rats. The histopathological evaluation indicated a significant restoration of liver structure as compared to silymarin. This study is the first scientific validation for the traditional use of eRoMi to understand its hepatoprotective activity.

Medicinal plants with hepatoprotective potentials against carbon tetrachloride-induced toxicity: a review

Background

Carbon tetrachloride (CCl4) is a well-characterized hepatotoxic agent. With rising cases of liver diseases, the identification, assessment, and development of hepatoprotective agents from plants source has become imperative.

Main body

With arrays of literature on plants with hepatoprotective potentials, this review sourced published literatures between 1998 and 2020 and systematically highlighted about 92 medicinal plants that have been reported to protect against CCl4-induced liver injury in animal models. The results show that herbal plants provide protection for the liver against CCl4 by downregulation of the liver marker enzymes and activation of antioxidant capacity of the liver cells with the restoration of liver architecture. We also provided the traditional and accompanying pharmacological uses of the plants. A variety of phytochemicals mostly flavonoids and polyphenols compounds were suggested to offer protection against liver injuries.

Conclusion

It can be concluded that there are a variety of phytochemicals in plant products with hepatoprotective activity against CCl4-induced toxicity in animal models.

In vivo Hepatoprotective and in vitro Radical Scavenging Activities of Extracts of Rumex abyssinicus Jacq. Rhizome

BACKGROUND

Liver diseases contribute a prominent global burden of mortality and morbidity. The current therapies of liver diseases have numerous limitations including severe adverse effects. This denotes that new more effective, safer, and cheaper drugs are required and medicinal plants used in traditional medicines often offer ideal opportunities. Accordingly, the present study aimed to evaluate the in vivo hepatoprotective and in vitro radical scavenging activities of dried rhizome extracts of Rumex abyssinicus (R. abyssinicus), which is traditionally claimed to provide hepatoprotection.

MATERIALS AND METHODS

Hepatoprotective activity of extracts was evaluated using carbon tetrachloride (CCl4)-induced liver injury in mice. Pre- and post-treatment models were employed to test the effect of the extracts and silymarin (standard drug). Serum biochemical markers and liver histopathology were used as parameters to evaluate hepatoprotective activities whereas in vitro radical scavenging activity was tested by 2, 2-diphenyl-2-picrylhydrazyl hydrate (DPPH) assay.

RESULTS AND CONCLUSION

Oral administration of CCl4 (1 ml/kg) significantly (P<0.001) raised the serum levels of liver enzyme markers compared to the normal control group. Pre-treatment with 125, 250, and 500 mg/kg of R. abyssinicus extract reduced the serum level of CCl4-induced rise in liver enzyme markers with the highest reduction observed at a dose of 500 mg/kg. Likewise, in the post-treatment model, the crude extract and butanol fraction at dose 500 mg/kg reduced levels of liver enzymes. Histopathological examinations revealed lesser liver damage of extract-treated mice compared to the toxic (CCl4-treated) controls. The in vitro radical scavenging activity of the different extracts showed concentration-dependent radical scavenging activity. Thus, the results of this study may justify the traditional use of the plant as a hepatoprotective agent.

CONCLUSION

Results of serum biochemical markers and histopathological examinations of CCl4-induced mice models, in the present study, show the hepatoprotective potential of extracts from the rhizome of R. abyssinicus.

Effect of curcumin analogue synthetic product from cullilawan oil for the liver damage treatment in male mice (Mus musculus L.)

The active component in cullilawan oil can be synthesized into curcumin analogue product, which has pharmacological activity. The synthesis process by using conventional and microwave methods can produce different isomer products. Different synthesis products and models of animal are used to provide different hepatoprotective effects. The aim of this study was to use the curcumin analogue synthetic products (AKS-k and AKS-m) from cullilawan oil in male mice (Mus musculus L.) liver damage treatment induced by carbon tetrachloride (CCl4). The in vivo method was employed using biochemical of blood and histopathological images of liver cells as indicators. The results showed that the curcumin analogue synthetic product using microwave methods had better pharmacological effects than the conventional method product in terms of the results of blood biochemical analysis and microscopic images of liver cells.

Medicinal plants with acetylcholinesterase inhibitory activity

Alzheimer's disease, a progressive neurodegenerative disease, is characterised by hypofunction of acetylcholine (ACh) neurotransmitter in the distinct region of brain. Acetylcholinesterase (AChE) is an enzyme that metabolises the ACh at synaptic cleft resulting in Alzheimer's disease. Medicinal plants have been used to treat numerous ailments and improve human health from ancient time. A traditional system of medicine is long recognised for its effective management of neurological disorders. The present review confers the scope of some common medicinal plants with a special focus on AChE-mediated central nervous system complications especially Alzheimer's disease. Literature suggests that medicinal plants reduce neuronal dysfunctions by reducing AChE activity in different brain regions. In some instances, activation of AChE activity by medicinal plants also showed therapeutic potential. In conclusion, medicinal plants have a wide scope and possess therapeutic potential to efficiently manage neurological disorders associated with AChE dysregulation.

Neoboutonia melleri var velutina Prain: in vitro and in vivo hepatoprotective effects of the aqueous stem bark extract on acute hepatitis models

BACKGROUND

Hepatitis is a liver inflammation caused by different agents and remains a public health problem worldwide. Medicinal plants are an important source of new molecules being considered for treatment of this disease. Our work aims at evaluating the hepatoprotective properties of Neoboutonia velutina, a Cameroonian medicinal plant.

METHODS

The aqueous extract has been prepared using phytochemical methods. HepG2 cells were used to assess anti-inflammatory properties of the extract at different concentrations. Acute hepatitis models (Carbon tetrachloride and Concanavalin A) were performed in mice receiving or not receiving, different extract doses by gavage. Liver injury was assessed using histology, transaminases and pro-inflammatory markers. Extract antioxidant and radical scavenging capacities were evaluated.

RESULTS

The extract led to a significant decrease in pro-inflammatory cytokine expression in vitro and to a remarkable protection of mice from carbon tetrachloride-induced liver injury, as shown by a significant decrease in dose-dependent transaminases level. Upon extract treatment, inflammatory markers were significantly decreased and liver injuries were limited as well. In the Concanavalin A model, the extract displayed weak effects.

CONCLUSIONS

Taking into account underlying mechanisms in both hepatitis models, we demonstrate the extract's radical scavenging capacity. Neoboutonia velutina displays a potent hepatoprotective effect mediated through radical scavenging properties.

Identification of Hepatoprotective Constituents in Limonium tetragonum and Development of Simultaneous Analysis Method using High-performance Liquid Chromatography

Background:

Limonium tetragonum, a naturally salt-tolerant halophyte, has been studied recently and is of much interest to researchers due to its potent antioxidant and hepatoprotective activities.

Objective:

In the present study, we attempted to elucidate bioactive compounds from ethyl acetate (EtOAc) soluble fraction of L. tetragonum extract. Furthermore, the simultaneous analysis method of bioactive EtOAc fraction of L. tetragonum has been developed using high-performance liquid chromatography (HPLC).

Materials and Methods:

Thirteen compounds have been successfully isolated from EtOAc fraction of L. tetragonum, and the structures of 1–13 were elucidated by extensive one-dimensional and two-dimensional spectroscopic methods including ¹H-NMR, ¹³C-NMR, ¹H-¹H COSY, heteronuclear single quantum coherence, heteronuclear multiple bond correlation, and nuclear Overhauser effect spectroscopy. Hepatoprotection of the isolated compounds against liver fibrosis was evaluated by measuring inhibition on hepatic stellate cells (HSCs) undergoing proliferation.

Results:

Compounds 1–13 were identified as gallincin (1), apigenin-3-O-β-D-galactopyranoside (2), quercetin (3), quercetin-3-O-β-D-galactopyranoside (4), (−)-epigallocatechin (5), (−)-epigallocatechin-3-gallate (6), (−)-epigallocatechin-3-(3″-O-methyl) gallate (7), myricetin-3-O-β-D-galactopyranoside (8), myricetin-3-O-(6″-O-galloyl)-β-D-galactopyranoside (9), myricetin-3-O-α-L-rhamnopyranoside (10), myricetin-3-O-(2″-O-galloyl)-α-L-rhamnopyranoside (11), myricetin-3-O-(3″-O-galloyl)-α-L-rhamnopyranoside (12), and myricetin-3-O-α-L-arabinopyranoside (13), respectively. All compounds except for 4, 8, and 10 are reported for the first time from this plant.

Conclusion:

Myricetin glycosides which possess galloyl substituent (9, 11, and 12) showed most potent inhibitory effects on the proliferation of HSCs.

SUMMARY

In the present study, we have successfully isolated 13 compounds from bioactive fraction of Limonium tetragonum. The structures of compounds isolated have been fully elucidated, and hepatoprotective activities of compounds against liver fibrosis were evaluated by measuring inhibition on hepatic stellate cells undergoing proliferation. Furthermore, the simultaneous analysis method of bioactive ethyl acetate fraction of L. tetragonum has been developed using HPLC. Ten compounds identified herein are reported for the first time from this plant.

Abbreviations used: HSQC: Heteronuclear single quantum coherence; HMBC: Heteronuclear multiple bond correlation; NOESY: Nuclear Overhauser effect spectroscopy; EGCG: Epigallocatechin-3-gallate; EGC: Epigallocatechin; HSC: Hepatic stellate cell; MTT: 3-(4,5-dimethylthiazol-2-yl)-2.5-diphenyltetrazolium bromide.

Hepatoprotective effect of the solvent extracts of Viola canescens Wall. ex. Roxb. against CCl4 induced toxicity through antioxidant and membrane stabilizing activity

Background

Viola canescens Wall. ex. Roxb. exhibits analgesic, antimalarial and antispasmodic activities. It is used folklorically for the treatment of liver diseases, hypertension, malaria and cancer. The current study investigates phytochemical constituents, antioxidant and hepatoprotective activity of solvent extracts of whole plant of Viola canescens.

Methods

Phytochemicals, acute toxicity study and antioxidant activity of Viola canescens methanolic extract (VCME), ethyl acetate fraction (EAF), and partially purified EAF (90% EAF and combination of 80% EAF + 20% methanol fraction (EAF + Me) was carried out. Hepatoprotective activity of VCME, EAF (200 and 400 mg/kg body weight) and partially purified EAF (50 mg/kg body weight) was investigated in carbon tetrachloride (CCl₄) intoxicated BALB/c mice for 7 days. Membrane stabilization effect was determined by hypotonic solution induced hemolysis while DNA ladder assay was carried out by polyacrylamide gel electrophoresis.

Results

Phytochemical screening of VCME showed the presence of alkaloids, phenols, flavonoids, saponins, carbohydrates, tannins and triterpenes. VCME, EAF (at 200 and 400 mg/kg body weight) and partially purified EAF (90% EAF and EAF + Me) at 50 mg/kg body weight significantly reduced the level of ALT, ALP, total bilirubin and restored the level of serum protein in comparison to CCl₄ treated group. A significant reduction in malondialdehyde (MDA) and elevation in catalase (CAT) and superoxide dismutase (SOD) level was observed in extract treated animals as compared to CCl₄ (p < 0.05). The IC₅₀ values in membrane stabilization potential for VCME, EAF and sodium salicylate were 3.7 ± 0.11, 3.4 ± 0.15 and 3.2 ± 0.09 mg/ml, respectively. Similarly, CCl₄ induced degradation of DNA was counteracted by VCME and EAF. The liver biopsy of mice treated with the solvent extracts showed remarkable restoration of normal histological archeitecture.

Conclusions

Viola canescens showed significant hepatoprotective potential due to its antioxidant and membrane stabilization effect.

Sasa veitchii extract suppresses carbon tetrachloride-induced hepato- and nephrotoxicity in mice

OBJECTIVE

The aim of this study was to investigate the therapeutic effects of a Sasa veitchii leaf extract (SE) on carbon tetrachloride (CCl₄)-induced hepato- and nephrotoxicity.

METHODS

Seven-week-old male ddy mice were orally administered SE or saline for seven days. Twenty-four hours after the last SE or saline administration, the mice were intraperitoneally injected with 3 g/kg CCl₄ or olive oil. The mice from each group were euthanized and bled for plasma analysis 24 h after the CCl₄/olive oil injection.

RESULTS

We found that pretreatment with SE completely abolished the CCl₄-induced mortality in the mice after 24 h. The mice pretreated with SE exhibited significantly decreased levels of functional markers, and reduced histological damage in both the liver and the kidney. Furthermore, we found that the SE pretreatment decreased lipid peroxidation and calcium levels in the liver. Although SE could not induce the free radical-scavenging metallothioneins, the plasma biological antioxidant power was significantly increased in the mice pretreated with SE.

CONCLUSION

Our findings demonstrate that prophylactic treatment with SE protects mice from CCl₄-induced lethal toxicity by decreasing oxidative stress in the liver and kidney, presumably by increasing biological antioxidant power.

The Cytoprotective Effect of Hyperoside against Oxidative Stress Is Mediated by the Nrf2-ARE Signaling Pathway through GSK-3β Inactivation

Glycogen synthase kinase-3β (GSK-3β) acts as a negative regulator of NF-E2 related factor 2 (Nrf2) by inducing Nrf2 degradation and nuclear export. Our previous study demonstrated that the flavonoid hyperoside elicits cytoprotection against oxidative stress by activating the Keap1-Nrf2-ARE signaling pathway, thus increasing the expression of antioxidant enzymes, such as heme oxygenase-1 (HO-1), superoxide dismutase (SOD) and catalase. However, the role of GSK-3β in hyperoside-mediated Nrf2 activation is unclear. Here, we demonstrate that in a normal human hepatocyte cell line, (L02), hyperoside is capable of inducing the phosphorylation of GSK-3β at Ser9 without affecting the protein levels of GSK-3β and its phosphorylation at Thr390. Lithium chloride (LiCl) and short interfering RNA (siRNA)-mediated inhibition of GSK-3β significantly enhanced the ability of hyperoside to protect L02 liver cells from H₂O₂-induced oxidative damage, leading to increased cell survival shown by the maintenance of cell membrane integrity and elevated levels of glutathione (GSH), one of the endogenous antioxidant biomarkers. Further study showed that LiCl and siRNA-mediated inhibition of GSK-3β increased hyperoside-induced HO-1 expression, and the effect was dependent upon enhanced Nrf2 nuclear translocation and gene expression. These activities were followed by ARE-mediated transcriptional activation in the presence of hyperoside, which was abolished by the transfection of the cells with Nrf2 siRNA. Furthermore, the siRNA-mediated inhibition of Keap1 also enhanced hyperoside-induced Nrf2 nuclear accumulation and HO-1 expression, which was relatively smaller than the effects obtained from GSK-3β siRNA administration. Moreover, Keap1 siRNA administration alone had no significant effect on the phosphorylation and protein expression of GSK-3β. Collectively, our data provide evidence that hyperoside attenuates H₂O₂ -induced L02 cell damage by activating the Nrf2-ARE signaling pathway through both an increase in GSK-3β inhibitory phosphorylation at Ser9 and an inhibition of Keap1 and that hyperoside-mediated GSK-3β inhibition exhibits more significant effects.

Isolation of major phenolics from Launaea spinosa and their protective effect on HepG2 cells damaged with t-BHP

CONTEXT

Some Launaea species (Asteraceae) are used traditionally to treat liver oxidative stress.

OBJECTIVE

The present study investigates the protective effects of isolated compounds from Launaea spinosa Sch. Bip. (Asteraceae) against oxidative stress on t-BHP-induced HepG2 cells.

MATERIALS AND METHODS

Major phenolic content from flowering aerial parts of L. spinosa was isolated and identified. The protective effects of isolated compounds (10 and 20 μM) against oxidative stress induced by tert-butyl hydroperoxide (t-BHP) in HepG2 cells were investigated through the measurement of aspartate aminotransferase (AST), alanine transaminase (ALT), and superoxide dismutase (SOD) levels.

RESULTS

A new phenolic compound identified as 2,3-diferulyl R,R-(+) methyl tartrate (6), in addition to five known metabolites, esculetin (1), esculetin-7-O-d-glucoside (cichoriin) (2), fertaric acid (3), acacetin-7-O-d-glucoside (4), and acacetin-7-O-d-glucuronic acid (5), were isolated. Oxidant-induced damage by 200 μM t-BHP in HepG2 cells was inhibited by compounds 1, 4, and 5 (10 and 20 μM), or quercetin (10 μM; positive control). The protective effects of compounds 1, 4, and 5 were associated with decreasing in AST, ALT, and SOD levels. Compound 4 (20 μM) decreased the AST level from 128.5 ± 13.9 to 7.9 ±1.8 U/mL. Meanwhile, compound 1 (20 μM) decreased ALT activity from 20.3 ± 7.0 to 7.6 ± 2.4 U/mL, while compound 5 decreased SOD levels from 41.6 ± 9.0 to 28.3 ± 3.4 mU/mg.

CONCLUSION

The major phenolic compounds isolated from L. spinosa displayed a significant cytoprotective effect against oxidative stress, leading to maintenance of the normal redox status of the cell.

Supplementation of Citrus maxima Peel Powder Prevented Oxidative Stress, Fibrosis, and Hepatic Damage in Carbon Tetrachloride (CCl4) Treated Rats

Citrus maxima peel is rich in natural phenolic compounds and has a long use in the traditional medicine. HPLC-DAD analysis on Citrus maxima peel powder exhibited the presence of various phenolic compounds such as caffeic acid and (−)-epicatechin. To determine the plausible hepatoprotective activity of Citrus maxima peel powder, we used carbon tetrachloride (CCl₄) treated rat model. Liver damage in rats was confirmed by measuring the AST, ALT, and ALP enzyme activities. In addition, lipid peroxidation products (MDA), nitric oxide, advanced protein oxidation products level (APOP), and catalase activities were also analyzed along with the histological profiling for the inflammatory cell infiltration, collagen, and iron deposition in liver. Dietary supplementation of Citrus maxima peel powder exhibited significant reduction of serum AST, ALT, and ALP activities in carbon tetrachloride treated rats. Moreover, Citrus maxima peel powder also showed a significant reduction of the oxidative stress markers (MDA, NO, and APOP level) and restored the catalase activity in CCl₄ treated rats. Histological examination of the liver section revealed reduced inflammatory cells infiltration, collagen, and iron deposition in CCl₄ treated rats. The results from this study demonstrated that Citrus maxima peel powder produced significant hepatoprotective action in CCl₄ administered rats.

Bactericidal effect of extracts and metabolites of Robinia pseudoacacia L. on Streptococcus mutans and Porphyromonas gingivalis causing dental plaque and periodontal inflammatory diseases

The mouth cavity hosts many types of anaerobic bacteria, including Streptococcusmutans and Porphyromonas gingivalis, which cause periodontal inflammatory diseases and dental caries. The present study was conducted to evaluate the antibacterial potential of extracts of Robinia pseudoacacia and its different fractions, as well as some of its natural compounds against oral pathogens and a nonpathogenic reference bacteria, Escherichia coli. The antibacterial activity of the crude extract and the solvent fractions (hexane, chloroform, ethyl acetate and butanol) of R. pseudoacacia were evaluated against S.mutans, P. gingivalis and E. coliDH5α by standard micro-assay procedure using conventional sterile polystyrene microplates. The results showed that the crude extract was more active against P. gingivalis (100% growth inhibition) than against S. mutans (73% growth inhibition) at 1.8 mg/mL. The chloroform and hexane fractions were active against P. gingivalis, with 91 and 97% growth inhibition, respectively, at 0.2 mg/mL. None of seven natural compounds found in R. pseudoacacia exerted an antibacterial effect on P. gingivalis; however, fisetin and myricetin at 8 µg/mL inhibited the growth of S. mutans by 81% and 86%, respectively. The crude extract of R. pseudoacacia possesses bioactive compounds that could completely control the growth of P. gingivalis. The antibiotic activities of the hexane and chloroform fractions suggest that the active compounds are hydrophobic in nature. The results indicate the effectiveness of the plant in clinical applications for the treatment of dental plaque and periodontal inflammatory diseases and its potential use as disinfectant for various surgical and orthodontic appliances.

Silymarin induces insulin resistance through an increase of phosphatase and tensin homolog in Wistar rats

BACKGROUND AND AIMS

Phosphatase and tensin homolog (PTEN) is a phosphoinositide phosphatase that regulates crucial cellular functions, including insulin signaling, lipid and glucose metabolism, as well as survival and apoptosis. Silymarin is the active ingredient in milk thistle and exerts numerous effects through the activation of PTEN. However, the effect of silymarin on the development of insulin resistance remains unknown.

METHODS

Wistar rats fed fructose-rich chow or normal chow were administered oral silymarin to identify the development of insulin resistance using the homeostasis model assessment of insulin resistance and hyperinsulinemic- euglycemic clamping. Changes in PTEN expression in skeletal muscle and liver were compared using western blotting analysis. Further investigation was performed in L6 cells to check the expression of PTEN and insulin-related signals. PTEN deletion in L6 cells was achieved by small interfering ribonucleic acid transfection.

RESULTS

Oral administration of silymarin at a dose of 200 mg/kg once daily induced insulin resistance in normal rats and enhanced insulin resistance in fructose-rich chow-fed rats. An increase of PTEN expression was observed in the skeletal muscle and liver of rats with insulin resistance. A decrease in the phosphorylation of Akt in L6 myotube cells, which was maintained in a high-glucose condition, was also observed. Treatment with silymarin aggravated high-glucose-induced insulin resistance. Deletion of PTEN in L6 cells reversed silymarin-induced impaired insulin signaling and glucose uptake.

CONCLUSIONS

Silymarin has the ability to disrupt insulin signaling through increased PTEN expression. Therefore, silymarin should be used carefully in type-2 diabetic patients.

Propofol Attenuates Toxic Oxidative Stress by CCl4 in Liver Mitochondria and Blood in Rat

Anti-oxidant effects of propofol (2, 6-diisopropylphenol) were evaluated agains carbon tetrachloridet CCl4 -induced oxidative stress in rat liver. 30 male rats were equally divided in to 6 groups (5 rats each). Group I (control), while Group II was given CCl4 (3 mL /Kg/day, IP). Animals of Groups III received only propofol (10 mg/Kg/day, IP). Group IV was given propofol+ CCl4. Group V was administered vitamin E (alpha-tocopherol acetate 15 mg/Kg/day, SC) .Animals of Group VII received alpha-tocopherol acetate + CCl4 once daily for two weeks. After treatment, blood and liver mitochondria were isolated. Anti-oxidant enzymes activity such as glutathione peroxidase (GPx), superoxide dismutase (SOD) and oxidative stress marker such as reduced glutathione (GSH) and lipid peroxidation (LPO) concentration were measured. Oxidative stress induced with CCl4 in liver mitochondria was evident by a significant increase in enzymatic activities of GPx, SOD, and LPO and decreased of GSH and vailability of mitochondria. Propofol and vitamin E restored CCl4-induced changes in GSH, GPx, SOD and LPO in blood and liver mitochondria. CCl4 decreased viability of mitochondria that was recovered by propofol and vitamin E. It is concluded that oxidative damage is the mechanism of toxicity of CCl4 in the mitochondria that can be recovered by propofol comparable to vitamin E.

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.

Antioxidant mediated protective effect of Parthenium hysterophorus against oxidative damage using in vitro models

BACKGROUND

Parthenium hysterophorus L. (Asteraceae) is a common weed occurring throughout the globe. In traditional medicine its decoction has been used for treatment of many infectious and degenerative diseases. This work was therefore designed to assess the phytochemical constitution of P. hysterophorus flower and root extracts and to evaluate their reducing power, radical scavenging activity as well as protective efficacy against membrane lipid damage.

METHODS

Dried flower and root samples were sequentially extracted with non-polar and polar solvents using Soxhlet apparatus. The phytochemical screening was done using standard chemical methods and thin layer chromatography. Total phenolic content was determined spectrophotometrically. Reducing power and hydroxyl radical scavenging activity assays were used to measure antioxidant activity. Protection against membrane damage was evaluated by inhibition of lipid peroxidation (TBARS assay) in rat kidney homogenate.

RESULTS

Flavonoids, terpenoids, alkaloids and cardiac glycosides were present in all the extract. The total phenol contents in flower and root extracts were found to be in the range 86.69-320.17 mg propyl gallate equivalent (PGE)/g and 55.47-253.84 mg PGE/g, respectively. Comparatively better reducing power was observed in hexane fractions of flower (0.405) and root (0.282). Benzene extract of flower and ethyl acetate fraction of root accounted for appreciable hydroxyl radical scavenging activity (75-77%). Maximum protection against membrane lipid peroxidative damage among flower and root extracts was provided by ethanol (55.26%) and ethyl acetate (48.95%) fractions, respectively. Total phenolic content showed positive correlations with reducing power and lipid peroxidation inhibition (LPOI) % in floral extracts as well as with hydroxyl radical scavenging activity and LPOI % in root extracts.

CONCLUSION

Study established that phytochemicals present in P. hysterophorus extracts have considerable antioxidant potential as well as lipo-protective activity against membrane damage.

Protective effects of Sonchus asper against KBrO3 induced lipid peroxidation in rats

BACKGROUND

Sonchus asper is traditionally used in Pakistan for the treatment of reproductive dysfunction and oxidative stress. The present investigation was aimed to evaluate chloroform extract of Sonchus asper (SACE) against potassium bromate-induced reproductive stress in male rats.

METHODS

20 mg/kg body weight (b.w.) potassium bromate (KBrO3) was induced in 36 rats for four weeks and checked the protective efficacy of SACE at various hormonal imbalances, alteration of antioxidant enzymes, and DNA fragmentation levels. High performance chromatography (HPLC) was used for determination of bioactive constituents responsible.

RESULTS

The level of hormonal secretion was significantly altered by potassium bromate. DNA fragmentation%, activity of antioxidant enzymes; catalase (CAT), peroxidase (POD), superoxide dismutase (SOD) and phase II metabolizing enzymes viz; glutathione reductase (GSR), glutathione peroxidase (GSHpx), glutathione-S-tansase (GST) and reduced glutathione (GSH) was decreased while hydrogen per oxide contents and thiobarbituric acid reactive substances (TBARS) were increased with KBrO3 treatment. Treatment with SACE effectively ameliorated the alterations in the biochemical markers; hormonal and molecular levels while HPLC characterization revealed the presence of catechin, kaempferol, rutin and quercetin.

CONCLUSION

Protective effects of Sonchus asper vs. KBrO3 induced lipid peroxidation might be due to bioactive compound present in SACE.