ISOLATION OF CUCURBITACIN-B FROM CUCUMIS CALLOSUS AND ITS HYPOGLYCEMIC EFFECT IN ISOLATED RAT ENTEROCYTES

Objective: The pericarp of fruits of Cucumis callous (Rottl.) Cogn. (Cucurbitaceae) is traditionally used for curing diabetes, epilepsy, and diarrhea. It has an active compound include Cucurbitacin-B (CuB), which acts as a potent inducer of CYP450 of rat enterocytes. This study was conducted with the aim of elaborating and reconciling our previous finding on the glucose-lowering effect of Cucumis callosus (Rottl.) Cogn. fruits.Methods: In vivo hypoglycemic potential for methanolic pericarp extracts from C callosus (MPCC, 350 mg/kg b.w. p. o), methanolic seed extract of C callosus (MSCC, 250 mg/kg b.w. p. o) and CuB (80 µg/kg b.w. p. o) were studied in streptozotocin (STZ, 55 mg/kg b.w. i. p) induced diabetic rats. Metformin (25 mg/kg b.w. p. o) served as reference drug. Ex vivo model of intestinal tissue preparation of Swiss albino rats named Single Pass Intestinal Perfusion (SPIP) technique was performed for ex vivo hypoglycemic study. The glucose levels in the serosal fluid were determined by commercially available glucose oxidase kit and compared with the standard drug metformin (0.1 mg/kg).Results: In vivo results showed that administration of MPCC (350 mg/kg b.w. p. o) and Cucurbitacin-B (80 µg/kg b.w. p. o) produced the hypoglycemic effect. The MPCC (1.4 mg/kg) and CuB (0.4 µg/kg) produced hypoglycemic effect in ex vivo technique. These effects are due to induction of 0.53 mµmoles of CYP450 proteins with maximum absorption at 454 mµ in rat enterocytes.Conclusion: The present investigation gave evidence that bitter pericarp of C callosus fruit has a hypoglycemic effect due to the presence of Cucurbitacin B as phytoconstituent but seeds did not have such effects

Polyherbal Therapies Attenuated Diabetes Induced Liver Damage

To evaluate glucose, liver function, lipid profile, urea, total protein, albumin, globulin and weight of liver tissues in diabetic rats. Thirteen groups of 6 rats each were used. Groups 1 and 2 Normal and Diabetic Control received 0.5 ml Dimethylsulphoxide; 3 and 4 received 5UI/Kg b.w insulin and 5mg/Kg b.w glibenclamide; 5, 6, 7 and 8  received 500 mg/Kg b.w of Vernonia amygdalina,  Moringa oleifera, Gongronema latifolium and Ocimum gratissimum extracts respectively; 9, 10 and 11 received 250 mg/ Kg b.w of M. oleifera/V. amygdalina, M. oleifera/ G. latifolium and M. oleifera/O. gratissimum respectively; 12 received 166.66mg/kg b.w of V. amygdalina/ G. latifolium/ O. gratissimum while 13 received 125mg/kg b.w of all extracts. There was reduction in liver weight, glucose, lipid profile and urea in all treated groups. Total protein, albumin, globulin and HDL-cholesterol increased in the treatment groups. Polyherbal treatments are potent at attenuating diabetes induced liver damage. Keywords: Hepatoprotective, Moringa oleifera, Vernonia amygdalina, Gongronema latifolium, Ocimum gratissimu

Assessment of titanium dioxide nanoparticle as treatment of Aeromonas hydrophila infection in Oreochromis niloticus

NO ABSTRACT AVAILABLENanoproducts became widely used materials all over the world. Antimicrobial properties of titanium dioxide (TiO2) nanoparticle (NP) were examined against Aeromonas hydrophila (A. hydrophila) bacteria and the minimum inhibitory concentration (MIC) was found to be 20 μg/ml of TiO2NP. In addition, the treatment efficacy of TiO2NP was examined in Oreochromis niloticus (O. niloticus) infected with A. hydrophila. One hundred and eighty fish (54±2.4 g b.w.) were divided into six groups (G). O. niloticus in G1, G2 and G3 were fed for 30 days with 0, 20 and 100 μg/g b.w. TiO2NP, respectively, while G4, G5 and G6 were i.p. injected with 0.2 ml distal water, 20 and 100 μg/g b.w. TiO2NP, respectively, for three times with ten days of interval. The blood parameters as well as some of the biochemical parameters of O. niloticus that received high dosage of TiO2NP were significantly affected regardless to the administration route. Elevation of the activities of glutathione peroxidase (GPx) and metallothionine (MT) were recorded with the high dosage. Furthermore, O. niloticus subjected to high dosage of TiO2NP had the lower survival rate (SR%) especially with the injection route (50%). On the other hand, no significant changes were demonstrated with the perceived TiO2NP MIC. The mortality rate (MR%) of challenged O. niloticus against A. hydrophila was decreased in case of TiO2NP MIC exposure, as G2 and G5 revealed 20 and 30%, respectively. Therefore, the 20 μg/g b.w. of TiO2NP could safely protect O. niloticus against A. hydrophila infection since no health hazards was observed. Meanwhile, health status of O. niloticus was adversely affected with high dosage of TiO2NP irrespective to the route of administration

Comparison between flying capacitor and modular multilevel inverter

The paper describes the operational principle of flying capacitor and modular multilevel inverters. The detailed discussions of dc link capacitors voltage balancing methods for both inverters are given in order to enable fair comparison. The causes of dc link capacitors voltage imbalance in flying capacitor multilevel inverter with more than three levels are highlighted. Computer simulation is used to compare the performance of both inverters under several operating conditions

Comparison between two VSC-HVDC transmission systems technologies : modular and neutral point clamped multilevel converter

The paper presents a detail comparison between two voltage source converter high voltage dc transmission systems, the first is based on neutral point-clamped (also known as HVDC-Light) and the second is based on innovative modular multilevel converter (known as HVDC-Plus). The comparison focuses on the reliability issues of both technologies such as fault ride-through capability and control flexibility. To address these issues, neutral point-clamped and three-level modular converters are considered in both stations of the dc transmission system, and several operating conditions are considered, including, symmetrical and asymmetrical faults. Computer simulation in Matlab-Simulink environment has been used to confirm the validity of the results

Evaluacija Hersbergova biotesta na glodavcima s pomoću tri referentna (anti) androgena

Under the umbrella of the Organization for Economic Cooperation and Development (OECD) the rodent Hershberger bioassay is being validated as an in vivo screen for the detection of (anti)androgens. As part of the validation work we studied trenbolone (TREN), 1,1-bis-(4-chlorophenyl)-2,2-dichloroethylene (p,p\u27-DDE) and vinclozolin (VIN). Oral intubation of castrated rats with TREN [0.3-1.5-8-40 mg kg-1 body weight (b.w.)] for ten days increased androgen-sensitive tissue weights (ASTW) at the high dose. p,p\u27-DDE (5-16-50-160 mg kg-1 b.w.) and VIN (0-3-10-30-100 mg kg-1 b.w.) orally administered for ten days produced a dose-dependent decrease in ASTW in castrated rats subcutaneously supplemented with testosterone propionate (0.4 mg kg-1 b.w.). p,p\u27-DDE also strongly increased liver weights and induced hepatocellular hypertrophy and thyroid follicular cell hypertrophy that was most likely mediated by liver enzyme induction. Our data strongly suggest that the OECD protocol of the rodent Hershberger bioassay describes a sensitive in vivo screen, capable of detecting weakly active (anti)androgens. Furthermore, our data may also indicate that thyroid effects could be assessed, if the protocol is amended accordingly.Hershbergerov biotest na glodavcima potvrđen je u sklopu OECD-ove međ unarodne studije kao in vivo test probira za otkrivanje tvari s afinitetom za androgene receptore. Našem laboratoriju povjereno je provođenje istraživanja s anaboličkim agensom trenbolonom (TREN) te s 1,1-bis-(4-klorfenil)-2,2-dikloretilenom (p,p\u27-DDE) i vinklozolinom (VIN). Samo visoka doza TREN primijenjena na kastriranim štakorima oralnom intubacijom [0,3 - 1,5 - 8 - 40 mg kg-1 tjelesne mase (t. m.)] tijekom deset dana, jako povećava masu tkiva osjetljivih na androgen. Oralno primijenjeni p,p\u27-DDE (5 - 16 - 50 - 160 mg kg-1 t. m.) i VIN (0 - 3 - 10 - 30 - 100 mg kg-1 t. m.) tijekom deset dana u štakora koji su dodatno primali testosteron propionat (0,4 mg kg-1 t. m., sc.), izazvali su ovisno o dozi smanjenje težine svih tkiva osjetljivih na androgen. Uz to je p,p\u27-DDE, takođ er ovisno o dozi, izazvao izrazito povećanje težine jetre i hipertrofiju stanica jetre i folikularnih stanica štitnjače, što je najvjerojatnije posljedica indukcije enzima jetre. Podaci u radu pokazuju da je opisani protokol osjetljiv za probir in vivo te sposoban za otkrivanje slabih (anti)androgena. Nadalje, podaci također upućuju na to da bi se mogli procjenjivati i učinci na štitnjaču ako se ovaj protokol prikladno unaprijedi

Amiloride reduces portal hypertension in rat liver cirrhosis

Objective This study aimed to investigate the effect of amiloride on portal hypertension. Amiloride is known to inhibit Na(+)/H(+) exchangers on activated hepatic stellate cells. Methods Liver cirrhosis in rats was induced by bile duct ligation (BDL) or thioacetamide (TAA) administration. The effects of zymosan for Kupffer cell (KC) activation or a thromboxane (TX) analogue (U46619) were tested in isolated perfused livers of cirrhotic rats and in vivo. Downstream mechanisms were investigated using Rho kinase inhibitor (Y-27632) or amiloride. Acute and chronic effects of amiloride and canrenoate on portal pressure were compared in perfused livers and in vivo. TXB(2) efflux was measured by ELISA. The phosphorylation state of moesin (p-moesin) as an indicator of Rho kinase activity and expression of the thromboxane synthase were assessed by western blot analyses. The activity of hepatic stellate cells was analysed by western blot and staining for alpha-smooth muscle actin (alpha-SMA). Results In BDL rats, KC activation via zymosan increased portal pressure. This was attenuated by the Rho kinase inhibitor Y-27632. Increased thromboxane efflux following zymosan infusion remained unaltered by Y-27632. The infusion of amiloride attenuated zymosan- and U46619-induced increases in portal perfusion pressure. In vivo, direct administration of amiloride, but not of canrenoate, lowered portal pressure. In TAA and BDL rats, treatment with amiloride for 3 days reduced basal portal pressure and KC-induced increases in portal pressure whereas canrenoate had no effect. In livers of amiloride-treated animals, the phosphorylation state of moesin and the number of alpha-SMA positive cells were reduced. Conclusions Amiloride lowers portal pressure in rat liver cirrhosis by inhibition of intrahepatic vasocontraction. Therefore, patients with cirrhosis and portal hypertension may benefit from amiloride therapy