Red Blood Cell Membrane Stabilization Research Articles

Antimicrobial, antioxidant and in vitro anti-inflammatory activity and phytochemical screening of Crotalaria pallida Aiton

The antimicrobial, antioxidant and anti-inflammatory activities, lipoxygenase, xanthine oxidase (XO), acetylcholinesterase activities and phenolic contents of different solvent extracts (ethanol, ethyl acetate, chloroform, petroleum ether and water) of Crotalaria pallida were evaluated using in vitro standard methods. These solvent extracts were most potent inhibiting all isolates with different zones of inhibition. The maximum inhibition of bacteria and fungi was observed from ethanol extract. The minimum microbial concentration (MMC) of the active extract was observed from ethanol, petroleum ether and ethyl acetate ranged from 0.3 to 3.2 mg/ml for the sensitive bacteria. In case of fungi, the minimum inhibitory concentration (MIC) of the active extracts ranged from 0.6 to 4.0 mg/ml. These data suggest that the C. pallida extracts analyzed are potential antimicrobial candidates with a broad range of activity. Phytochemical analysis was conducted to all the solvent extracts to their constituents. The level of total phenol, alkaloids, terpenoids, saponins, phenols, steroids and tannins from ethanol, ethyl acetate and petroleum ether extracts were higher. The antioxidant activities of different solvent extracts of C. pallida were determined by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and ferrous reducing antioxidant property (FRAP) methods. Ascorbic acid and butylated hydroxytoluene (BHT) were used as standard for antioxidant activity. The ethanol, ethyl acetate and petroleum ether extracts possessed strong scavenging activity in both DPPH and FRAP methods. The ethanol, ethyl acetate and petroleum ether had showed free radical inhibition of 88, 72 and 73 and 3617.89 ± 0.03, 2189.33 ± 0.03 and 1133.26 ± 0.01, respectively. The in vitro anti-inflammatory activities were evaluated using albumin denaturation, membrane stabilization and proteinase inhibitory activities using all the solvent extracts. The ethanol, ethyl acetate and petroleum ether showed activity by inhibiting the heat induced albumin denaturation and red blood cells membrane stabilization with 83.17, 71.33 and 58.14 and 68.21, 61.44 and 60.72 g/ml, respectively. The proteinase activity was significantly inhibited by the ethanol (82.53), ethyl acetate 74.31) and petroleum ether (62.92) g/ml. Aspirin was used as standard drug for the study of antiinflammatory activity. In addition, the ethanol, ethyl acetate and petroleum ether extracts showed antilipoxygenase activity and they also exhibited a moderate xanthine oxidase and acetylcholinesterase inhibitory activity.

Antimicrobial, antioxidant and in vitro anti-inflammatory activity and phytochemical screening of water extract of Wedelia trilobata (L.) Hitchc.

The aim of the study was to evaluate antimicrobial, antioxidant and anti-inflammatory activity of dry and fresh parts of leaf, stem and flower from the water extract of Wedelia trilobata. The antimicrobial activity of water extracts of fresh and dry parts against 9 different strains of bacteria and 11 different species of fungi were determined using standard method (paper disc method). The fresh parts water extracts showed that, leaf and flower extracts were most potent inhibiting all isolates of with different zones of inhibition but did not inhibited the growth of fungi tested. All the extracts have only moderately inhibited the all fungi. The minimum microbial concentration (MMC) of the active extract was observed from fresh part extracts of leaf, flower and stem ranged from 0.4 to 5.0 mg/ml for the sensitive bacteria. In case of fungi, the minimum inhibitory concentration (MIC) of the active extracts ranged from 2.4 to 6.0 mg/ml. Together, these data suggest that the W. trilobata fresh parts extracts analyzed are potential antimicrobial candidates with a broad range of activity. Phytochemical screening of extracts showed the presence of tannins, cardiac glycosides, flavonoids, terpenoids, phenols, saponins and coumarins. Leaf and flower water have showed highest total phenolic content. In 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and ferric ion reducing antioxidant power (FRAP) method, the leaf and flower had showed free radical inhibition of 86, 83 and 1623.21, 1611.26, respectively and they also showed in vitro antiinflammatory activity by inhibiting the heat induced albumin denaturation and red blood cells membrane stabilization with 89.61 and 86.81 and 78.82, 76.65 g/ml, respectively. Proteinase activity was also significantly inhibited by the leaf (83.91 g/ml) and flower (81.17 g/ml). From the result, it is concluded that phytochemicals present in the W. trilobata extract may be responsible and can be used as antimicrobial, antioxidant and anti-inflammatory agent.

Phytochemical Screening, Antimicrobial and in vitro Anti-inflammatory Activity of Endophytic Extracts from Loranthus sp.

Four different endophytes were isolated from different parts of Loranthus sp. Methanol and water extracts of all the endophytes was assessed for its antimicrobial and anti-inflammatory activity and phytochemical screening. Phytochemical analysis revealed the presence of tannins, flavonoids, terpenoids, steroids, alkaloids, phenols and saponins. The antimicrobial efficacy was determined using paper disc diffusion method against different fungi and bacteria. Sensitivity in terms of zones of inhibition and phytochemical composition of the all endophytic extracts were also determined. The results show that, A. niger, Penicillium sp., Alternaria alternata extracts effective against all the bacteria and fungi tested, whereas A. flavus extract was failure in inhibiting the growth of all bacteria and bacteria. In vitro anti-inflammatory activity was evaluated using albumin denaturation, membrane stabilization assay and proteinase inhibitory assay. Aspirin was used as a standard drug for the study of anti-inflammatory activity. A. niger, Penicillium sp. and Alternaria alternata methanol fractions showed in vitro anti-inflammatory activity by inhibiting the heat induced albumin denaturation (87.88, 86.89, 87.03 g/ml) and red blood cells membrane stabilization with 78.42, 77.61, 77.98 g/ml respectively. Proteinase activity was also significantly inhibited by the A. niger (85.21 g/ml), Alternaria alternata (84.09 g/ml) and Penicillium sp. (79.17 g/ml). BSA anti-denaturation and HRBC membrane stabilization assay indicated that the methanol extracts of A. niger, Penicillium sp., Alternaria alternata possess constituents with anti-inflammatory properties. From the result, it is concluded that phytochemicals (tannins, flavonoids, terpenoids, phenols, steroids, alkaloids and saponins) present in the A. niger, Penicillium sp., Alternaria alternata extract may be responsible for the antimicrobial and anti-inflammatory activity.

Anti–inflammatory activity of the glandular extracts of Thunnus alalunga

Objective To evaluate the anti-inflamattory activity of Thunnus alalunga by both in vitro and in vivo methods. Methods Anti-inflammatory activity of the chloroform water extract of Thunnus alalunga was done by both in vitro and in vivo methods. In vitro method was done by human red blood cells membrane stabilization method (HRBC). In vivo evaluation was estimated on Wister albino rats. Acute toxicity studies were done on the extract and no toxicity was reported. Results The percentage protection exhibited by 300 mg/mL concentration was more when compared to the other ones. The 400 mg/mL concentration showed potent activity on comparison with the standard during in vivo evaluation. Conclusions In both means of estimation the extract of Thunnus alalunga was found to possess significant anti-inflammatory activity.

Targeted deletion of α-adducin results in absent β- and γ-adducin, compensated hemolytic anemia, and lethal hydrocephalus in mice

AbstractIn the red blood cell (RBC), adducin is present primarily as tetramers of α- and β-subunits at spectrin-actin junctions, or junctional complexes. Mouse RBCs also contain small amounts of γ-adducin. Platelets contain α- and γ-adducin only. Adducin functions as a barbed-end actin capping protein to regulate actin filament length and recruits spectrin to the ends of actin filaments. To further define adducin's role in vivo, we generated α-adducin knockout mice. α-Adducin is absent in all tissues examined in homozygous null mice. In RBCs, β- and γ-adducin are also absent, indicating that α-adducin is the limiting subunit in tetramer formation at the spectrin-actin junction. Similarly, γ-adducin is absent in α-null platelets. α-Adducin–null mice display compensated hemolytic anemia with features characteristic of RBCs in hereditary spherocytosis (HS), including spherocytes with significant loss of surface area, decreased mean corpuscular volume (MCV), cell dehydration, and increased osmotic fragility. Platelets maintain their normal discoid shape, and bleeding times are normal. α-Adducin–null mice show growth retardation at birth and throughout adulthood. Approximately 50% develop lethal communicating hydrocephalus with striking dilation of the lateral, third, and fourth ventricles. These data indicate that adducin plays a role in RBC membrane stability and in cerebrospinal fluid homeostasis.

In vitro and In vivo anti-inflammatory activity of leaves of Symplocos cochinchnensis (Lour) Moore ssp laurina

The anti-inflammatory activities of different extracts of leaves Symplocos cochinchinensis Lour ssp laurina (Symplococaceae) were investigated for i n vitro anti-inflammatory activity by human red blood cell membrane stabilization method. The methanol extract showed effective in vitro anti-inflammatory activity was screened for in vivo antiinflammatory activity by carrageenan-induced paw edema in rat model. The potency of the extracts was compared with standard diclofenac (50 mg/kg). The methanol extract showed significant membrane stabilizing action on human red blood cell membrane and reduction of edema in carrageenan induced rat paw edema model.

Antioxidant and Membrane Stabilizing Properties of Ichnocarpus frutescens

The antioxidant potential of the 70% methanolic extract of Ichnocarpus frutescens was assessed by the 1, 1-diphenyl-2-picrylhydrazyl (DPPH), the hydrogen peroxide, the nitric oxide, the reducing power and the lipid peroxidation inhibition (thiobarbituric acid-reactive substances production) and the red blood cell (RBC) membrane stabilization assays. The extract showed significant antioxidant activities in all assays in a dose dependent manner. The extracts displayed notable activities in reactive oxygen species (ROS) scavenging which could be attributed to the high phenolic content of this extract. Moreover, I. frutescens extract showed strong reducing power and an ability to suppress lipid peroxidation. Suppression of lipid peroxidation and nitric oxide scavenging would be the probable mechanism of the stabilization of the RBC membrane. In the DPPH radical scavenging assay the IC 50 value of the extract was found to be 23.75 μg/mL. The extract inhibited the nitric oxide radicals generated from sodium nitroprusside and the IC 50 value was found to be 69.69 μg/mL, comparable to that of 86.83 μg/mL for the positive control ascorbic acid.

814 ALTERED PATTERN OF SPECTRIN PHOSPHORYLATION IN SENESCENT HUMAN RED CELLS

The membrane protein spectrin is important in the maintenance of red blood cell (RBC) membrane shape and stability. We have previously shown that it is phosphorylated at 4 sites clustered near the C-terminus of its smaller subunit. These phosphates may control spectrin's interaction with other membrane proteins. To test whether spectrin phosphorylation changed with RBC age, intact RBCs were labeled with 33PO4, fractionated by density, and assayed for age (using marker enzymes) and for the position and number of 33PO4's in spectrin dimer. 33p-spectrin prepared from old (average=90 d of age) and control RBCs had identical numbers of 33p phosphates; however the distribution of 33p was altered in old RBCs. 33P-label in the most distal phosphorylation site was reduced from 0.95±0.05 moles/mole spectrin dimer to 0.25±0.05(n=4) and was proportionally increased in a more proximal site(s). Similar changes occurred in RBCs incubated in the absence of substrate for 20 hrs (but not for 12 hrs). Phosphorylation of purified 33P-spectrin from old RBCs with spectrin kinase and γ-32P-ATP produced the same number and distribution of phosphates as control. We conclude that the location of spectrin phosphates in senescent or metabolically-depleted RBCs is altered. This may be caused by enzymatic redistribution of isotopic label or by a structural alteration of the distal phosphorylation site. This change may contribute to the membrane instability and eventual demise of the aged RBC.

Effects of nitrate, nitrite and vitamin e on methemoglobin formation in rats

Female rats were fed vitamin E deficient, control 50 ppm vitamin E, and high vitamin E 300 ppm diets containing 7% corn oil and 3% cod liver oil, and were administered gradually increasing levels of nitrate (up to 1600 ppm), then nitrite (up to 3000 ppm), in their drinking water over a 25-week period. A decreased growth rate was observed in the nitrate/nitrite-treated rats when vitamin E levels were low or zero, but not when a high level of vitamin E was present. Blood methemoglobin levels were monitored over the 25-week period and were found to be unaffected by the level of dietary vitamin E. This study suggests that red blood cell membrane stability does not affect methemoglobin formation. Temporary elevation of methemoglobin levels in the blood was observed with high levels of nitrite administration, however, an eventual reconversion to hemoglobin was achieved even though the high level of nitrite administration was continued. These results suggest that the rats have an inducible, adaptive mechanism to counteract the effects of nitrite ingestion, to a level as high as 3000 ppm in their drinking water.