Protective effect of aqueous extract of Phyllanthus fraternus against bromobenzene induced changes on cytosolic glutathione S-transferase isozymes in rat liver.

The aim of this study was to investigate beneficial effect of aqueous extract of Phyllanthus fraternus (AEPF) on bromobenzene (BB) induced changes on cytosolic glutathione S-transferase (GST) isozymes in rat liver. Administration of BB significantly decreased the activity of GST, however, prior administration of AEPF prevented the BB induced decrease in GST activity. Further the cytosolic GSTs were purified from 3 groups of animals (control, BB and AEPF+BB administered) and resolved into three protein bands on SDS-PAGE. Densitometric analysis showed a significant decrease in BB group compared to control. Further, 2D PAGE analysis resolved these proteins into 8 bands which were identified as five isozymes of alpha, two of Mu and one of theta by MALDI-TOF MS and also observed decreased levels of isozymes in BB group. However, on prior administration of AEPF significantly prevented the BB induced decrease in GSTs and restored to normal levels.

Mechanism of antibacterial action of the alcoholic extracts of Hemidesmus indicus (L.) R. Br. ex Schult, Leucas aspera (Wild.), Plumbago zeylanica L., and Tridax procumbens (L.) R. Br. ex Schult.

Herbal products derived from Hemidesmus indicus (L.) R. Br. ex Schult, Leucas aspera (Wild.), Plumbago zeylanica L., and Tridax procumbens (L.) R. Br. ex Schult. are widely used in traditional medicine. Though the extracts of these plants were found to be antimicrobial in nature and have the potential to be used in clinics, the mechanism of action of is not reported. The ethanolic extracts of Hemidesmus indicus (L.) R. Br. ex Schult, Hemidesmus indicus ethanolic extract (HIEE), Leucas aspera (Wild.), Leucas aspera ethanolic extract (LAEE), Plumbago zeylanica L., Plumbago zeylanica ethanolic extract (PZEE), and Tridax procumbens (L.) R. Br. ex Schult, Tridax procumbens ethanolic extract (TPEE) were tested for their antibacterial activity against E. coli. Antibacterial activity was analyzed by CFU assay and the effect on the bacterial membrane by fluorescence activated cell sorting and scanning electron microscopy. LAEE, PZEE, and HIEE displayed potent bacterial killing activity in a time and concentration dependent manner. TPEE did not display appreciable antibacterial activity. The antibacterial action involved disruption of membrane potential, inner membrane permeabilization, blebbing and leakage of cellular contents. Our results contribute to the understanding of the antibacterial mechanism of alcoholic extracts of the medicinal plants used in this study.

In vitro antioxidant, antiproliferative, and phytochemical study in different extracts of Nyctanthes arbortristis flowers.

Nyctanthes arbortristis L. (Oleaceae) is widely used in the Indian system of traditional medicine and is reported to have various biological activities. The present study was intended to evaluate the antioxidant and antiproliferative activities of flower extracts of Nyctanthes arbortristis. The shade dried flowers were extracted with 95% ethanol under sonication and the antioxidant activities were investigated using in vitro assays along with the determination of phytochemical constituents (total polyphenol and total flavonoid). Arborside C and ß-monogentiobioside ester of α-Crocetin were identified in crude active extracts through LCMS/MS analysis. The antiproliferative activity was carried out by MTT assay by employing different human cancer cell lines. The lowest IC50 value of 24.56 ± 6.63 µg/mL was observed against Colo 205 cell line. The extract exhibited significant antioxidant and antiproliferative properties and the observed biological activities in this study provide scientific validation of ethnomedicinal use of this plant.

Protective effect of Hemidesmus indicus L. R. Br. against bromobenzene-induced mitochondrial dysfunction in rat kidney.

Hemidesmus indicus (HI) is used in ancient Indian traditional herbal medicine to treat hepatic and renal disorders. The present study was designed to investigate the protective effect of HI aqueous extract against bromobenzene induced mitochondrial dysfunction in rat kidneys. Rats were administered bromobenzene with or without prior administration of HI or vitamin E. At the end of the experiment animals were sacrificed and kidneys were obtained to study mitochondrial function, oxidative stress parameters and histopathology. Administration of bromobenzene caused significant changes like: decrease in the mitochondrial respiration and P/O ratios, increase in lipid peroxidation and protein oxidation, and decrease in the activities of antioxidant enzymes (catalase, glutathione reductase, glutathione peroxidase and superoxide dismutase) in mitochondria with significant histopathological changes in the kidney. Prior administration of HI extract showed a significant protection against bromobenzene induced changes in the kidney and this effect is attributed to the antioxidant and free radical scavenging potential of the HI. The protection was much better with HI compared to vitamin E.

Protective effect of Phyllanthus fraternus against bromobenzene induced mitochondrial dysfunction in rat liver mitochondria.

The objective of the current study was to investigate the protective effect of an aqueous extract of Phyllanthus fraternus (AEPF) against bromobenzene induced mitochondrial dysfunction in rat liver mitochondria. Administration of bromobenzene (10 mmol/kg body wt.) significantly decreased the rate of respiration (with glutamate+malate or succinate as substrates), abolished respiratory control ratio (RCR) and P/O ratios completely. There was a significant increase in the levels of lipid peroxides and protein carbonyls and a significant decrease in the total sulphydryl groups. The activities of antioxidant enzymes like catalase, glutathione peroxidase (GPx), glutathione reductase (GR) and superoxide dismutase (SOD) were decreased. The levels of antioxidants like reduced and oxidized glutathione were significantly decreased compared to control. Administration of rats with an AEPF (100mg/kg body wt.) prior to bromobenzene administration showed several beneficial effects like: (i) complete protection on mitochondrial respiration, RCR and P/O ratios (ii) lipid peroxides and protein carbonyl levels were significantly lowered (iii) increased the levels of sulphydryl groups and the activity of antioxidant enzymes and (iv) significant increase in the levels of reduced and oxidized glutathione. Vitamin E was used as positive control and bromobenzene induced mitochondrial dysfunction was protected better with AEPF compared to vitamin E.