Antioxidant and antihyperglycemic activity of Sophora alopecuroides seed on streptozotocin-nicotinamide induced diabetic rats / Abdulwali Ablat

Sophora alopecuroides seed (SAS) was extracted with chloroform, ethanol and distilled water. The TLC result showed the presence of alkaloids in all of the extracts and the total alkaloid contents was 7.56%. The alkaloids were separated and identified with Q-TQF MS with known reference standard and were found that Sophora alopecuroides seed contained alkaloids namely sophocarpine, matrine, baptifoline, oxysophocarpine, oxymatrine, sophocarpine dimer, oxysophocarpine dimer, oxymatrine dimer and sophoranol-N-oxide dimer. The in vitro bioassays were performed to determine the antioxidant activity and glycogen phosphorylase enzyme inhibition activity of Sophora alopecuroides seed in ethanol and water extracts. In all of the bioassays, ethanol extract had showed highest activities. In DPPH assay the IC50 value of ethanol extract was 155.33 ± 0.06 μg/ml while in FRAP assay the IC50 value of ethanol extract was 9.71 ± 0.02 μg/ml. In GPa enzyme assay the IC50 of ethanol Sophora alopecuroides seed extract was 581.61 μg/ml. Acute toxicity of ethanol Sophora alopecuroides seed extract was tested at increasing dose level in non-diabetic rats and no toxic effects were observed in male rats at a dose of 5 g/kg body weight. The ethanol Sophora alopecuroides seed extract at the dose of 500 mg/kg was capable of decreasing the glycemia of non-diabetic rats during an oral glucose tolerance test (OGTT). The treatment with SAS at the dose of 500 mg/kg to the diabetic rats for 28 days decreased fasting blood glucose levels significantly compared to the 0th day. The 95% ethanol SAS extract at the dose of 250 mg/kg and 500 mg/kg body weight significantly (*P < 0.05) decreased serum triglycerides and total cholesterol levels, and increased serum HDL levels compared to the diabetic control. Therefore, these results validate the traditional use of Sophora alopecuroides seed as an antidiabetic remedy

The Antioxidant and Xanthine Oxidase Inhibitory Activity of Plumeria rubra Flowers

Plumeria rubra Linn of the family Apocynaceae is locally known in Malaysia as “Kemboja”. It has been used by local traditional medicine practitioners for the treatment of arthritis-related disease. The LCMS/MS analysis of the methanol extract of flowers (PR-ME) showed that it contains 3-O-caffeyolquinic acid, 5-caffeoquinic acid, 1,3-dicaffeoquinic acid, chlorogenic acid, citric acid, 3,3-di-O-methylellagic acid, kaempferol-3-O-glucoside, kaempferol-3-rutinoside, kaempferol, quercetin 3-O-α-l-arabinopyranoside, quercetin, quinic acid and rutin. The flower PR-ME contained high amounts of phenol and flavonoid at 184.632 mg GAE/g and 203.2.2 mg QE/g, respectively. It also exhibited the highest DPPH, FRAP, metal chelating, hydrogen peroxide, nitric oxide superoxide radical scavenging activity. Similarly, the XO inhibitory activity in vitro assay possesses the highest inhibition effects at an IC50 = 23.91 μg/mL. There was no mortality or signs of toxicity in rats at a dose of 4 g/kg body weight. The administration of the flower PR-ME at doses of 400 mg/kg to the rats significantly reduced serum uric acid 43.77%. Similarly, the XO activity in the liver was significantly inhibited by flower PR-ME at doses of 400 mg/kg. These results confirm that the flower PR-ME of P. rubra contains active phytochemical compounds as detected in LCMS/MS that contribute to the inhibition of XO activity in vitro and in vivo in reducing acid uric level in serum and simultaneously scavenging the free radical to reduce the oxidative stress

Evaluation of antidiabetic and antioxidant properties of brucea javanica seed

The ethanol extract of B. javanica seed was fractionated with solvents of different polarities and tested for antioxidant activities by several assays including DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP), ferrous ion chelating activity (FCA), and nitric oxide radical scavenging activity (NORSA) along with their polyphenolic contents. Antidiabetic activity was evaluated both in vitro and in vivo using a glycogen phosphorylase α (GPα) inhibition assay and oral glucose tolerance test (OGTT) in nondiabetic rats. The ethyl acetate fraction (EAF), rich in tannin, exhibited the strongest antioxidant activities to DPPH, FRAP, and NORSA, except for FCA. The EAF also exerted a dose-depended inhibition of GPα (IC50 = 0.75 mg/ml). Further evaluation of hypoglycemic effect on OGGT indicated that rats treated with EAF (125 mg/kg bw) showed a 39.91% decrease (P < 0.05) in blood glucose levels at 30 min, and continuous fall (P < 0.05) of 28.89% and 20.29% was observed in the following hours (60 and 90 min) compared to the normal control during OGTT. The EAF was applied to polyamide column chromatography, and the resulting tannin-free fraction was tested for both GPα inhibition and antioxidant (DPPH only) activity. The GPα inhibitory activity was retained, while antioxidant activity was lost (4.6-fold) after tannin removal. These results concluded that the GPα inhibitory activity initially detected was primarily due to the compounds other than tannins, whereas antioxidant activity was mainly due to the tannins

In vitro antiplasmodial and antioxidant activities of bisbenzylisoquinoline alkaloids from Alseodaphne corneri Kosterm

AbstractObjectiveTo study antiplasmodial and antioxidant activities of the isolation of alkaloids from the active dichloromethane extract of Alseodaphne corneri.MethodsPhytochemical studies of the crude extract led to the isolation of six alkaloids using recycle high performance liquid chromatography and preparative thin layer chromatography. The antiplasmodial activity of the isolated compounds was evaluated using the histidine-rich protein II assay. The isolated alkaloids were also tested for their antioxidant activity using three different assays; DPPH, ferric reducing ability of plasma and metal chelating assays.ResultsMalaria infection caused the formation of free radicals which subsequently led to oxidative stress and apoptosis. The antioxidant properties of the alkaloids under investigation revealed that in addition to the antiplasmodial activity, the alkaloids could also prevent oxidative stress. (+)-laurotetanine and (+)-norstephasubine exhibited strong antiplasmodial activities with IC50 values of 0.189 and 0.116 μM, respectively.ConclusionsInterestingly, the two most potent compounds that exhibit antiplasmodial activity also exhibit good antioxidant activities. The crude dichloromethane extract and the isolated compounds exert substantial antiplasmodial and antioxidative activities which in turn suppress oxidative stress and cause less damage to the host

Gastroprotective activity of ethyl-4-[(3,5-di-tert-butyl-2-hydroxybenzylidene) amino]benzoate against ethanol-induced gastric mucosal ulcer in rats.

BACKGROUND: The study was carried out to determine the cytotoxic, antioxidant and gastro-protective effect of ethyl-4-[(3,5-di-tert-butyl-2-hydroxybenzylid ene)amino] benzoate (ETHAB) in rats. METHODOLOGY/PRINCIPAL FINDINGS: The cytotoxic effect of ETHAB was assessed using a MTT cleavage assay on a WRL68 cell line, while its antioxidant activity was evaluated in vitro. In the anti-ulcer study, rats were divided into six groups. Group 1 and group 2 received 10% Tween 20 (vehicle). Group 3 received 20 mg/kg Omeprazole. Groups 4, 5 and 6 received ETHAB at doses of 5, 10, and 20 mg/kg, respectively. After an hour, group 1 received the vehicle. Groups 2-6 received absolute ethanol to induce gastric mucosal lesions. In the WRL68 cell line, an IC50 of more than 100 µg/mL was observed. ETHAB results showed antioxidant activity in the DPPH, FRAP, nitric oxide and metal chelating assays. There was no acute toxicity even at the highest dosage (1000 mg/kg). Microscopy showed that rats pretreated with ETHAB revealed protection of gastric mucosa as ascertained by significant increases in superoxide dismutase (SOD), pH level, mucus secretion, reduced gastric lesions, malondialdehyde (MDA) level and remarkable flattened gastric mucosa. Histologically, pretreatment with ETHAB resulted in comparatively better gastric protection, due to reduction of submucosal edema with leucocyte infiltration. PAS staining showed increased intensity in uptake of Alcian blue. In terms of immunohistochemistry, ETHAB showed down-expression of Bax proteins and over-expression of Hsp70 proteins. CONCLUSION/SIGNIFICANCE: The gastroprotective effect of ETHAB may be attributed to antioxidant activity, increased gastric wall mucus, pH level of gastric contents, SOD activity, decrease in MDA level, ulcer area, flattening of gastric mucosa, reduction of edema and leucocyte infiltration of the submucosal layer, increased PAS staining, up-regulation of Hsp70 protein and suppressed expression of Bax

Immunohistochemistry staining of Bax proteins.

<p>The analysis revealed a down-expression of Bax protein in the stomach of rats pretreated with ETHAB (d, e and f) and Omeprazole (c) compared with the ulcer control group (b) and normal group (a)(Magnification 20x).</p

Periodic Acid Schiff (PAS) staining of mucosal glycoproteins.

<p>The observed intense magenta color in the apical epithelial cells in the groups pretreated with ETHAB (d, e and f) and Omeprazole (c) compared with the ulcer control group (b) and normal group (a)(Magnification 10x).</p

IC₅₀ values based on antioxidant evaluation of ETHAB in relation to other standard compounds.

<p>All values are expressed as mean ± SEM.</p

Mean of total protein concentration, superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels in stomach tissue homogenates of normal control, ulcer control, positive control, and ETHAB (5, 10 and 20 mg/kg) treated groups.

<p>*The mean difference is significant at the 0.05 level (<i>p<0.05</i>) compared to PC.</p>#<p>The mean difference is significant at the 0.05 level (<i>p<0.05</i>) compared to UC.</p

Immunohistochemistry staining of Hsp70 proteins.

<p>The analysis revealed an over expression of Hsp 70 protein in the stomach of rats pretreated with ETHAB(d, e and f) and Omeprazole (c) compared with the ulcer control group (b) and normal group (a)(Magnification 20x).</p