Optimization of RHDV type 1 and 2 inactivation modes

The purpose of these studies was to optimize RHDV type 1 and 2 (RHDV1 and RHDV2) inactivation modes to use the obtained antigens in inactivated vaccines and diagnosticums. The inactivating effect of aminoethylethylenimine and β-propiolactone was studied in different concentrations in correlation with the exposure time and temperature. The correlation between the inactivating effect of the compound used and the accepted test conditions (concentration, temperature, and exposure time) was studied on a group of rabbits, each of which was injected intramuscularly with 1 cm3 of the inactivated material sample. At the end of the maximum exposure interval, a control sample of the viral material, kept under the same conditions without any inactivant added was similarly tested. Lethality was considered to evaluate the damaging action in the test and control groups: L = m/n, where m is the number of dead animals; n is the total number of rabbits in the group for testing of the inactivated material sample. The postmortem diagnosis was confirmed by testing the rabbit liver tissue homogenate for relative antigens using ELISA. It was found that aminoethylethylenimine and β-propiolactone did not have the same effect on the studied variants of the virus. In order to preserve at maximum the antigenic structures of the virus, the following inactivation modes were considered to be optimal: for RHDV1-aminoethylethylenimine at a concentration of 0.3% at 37 °C, exposure time – 72 hours, or β-propiolactone at a concentration of 0.1–0.3% at 25–37 °С, exposure time – 24–48 hours; for RHDV2 – aminoethylethylenimine at a concentration of 1% at 37 °C, exposure time – 72 hours, or β-propiolactone at a concentration 0.3% at 25 °С, exposure time – 24 hours.

Effect of fenugreek (Trigonella foenum-graecum) on experimentally induced diabetes mellitus in male rabbits

The study was conducted to investigate the effect of orally administered fenugreek on some biochemical parameters in diabetic male rabbits experimentally induced by intraperitoneal injection of alloxan monohydrate 75 mg/kg. Twenty-five male local breed rabbits were divided into 5 equal groups; G1 normal control group, G2 diabetic non-herb treated, G3 normal rabbit treated with the herb. While each of G4 and G5 was diabetic rabbits treated with 2 and 3g/day single oral dose of fenugreek for 30 consecutive days respectively. A blood sample was taken at zero-day, 2 weeks and 4 weeks for estimation of serum glucose, cholesterol, triglyceride, ALT, and AST. At the end of the experiment, animals were sacrificed in order to prepare liver tissue homogenate to calculate the level of Malondialdehyde (MDA) and glutathione (GSH) to explore the role of fenugreek as an antioxidant herb. Results were revealed an increase in serum glucose, cholesterol, triglyceride, ALT, AST, and MDA level and reduced glutathione level in G2. While, oral administration of fenugreek showed a significant reduction in total lipids and serum sugar in diabetic rabbits and have no any adverse effect on the main parameters of the body, the herb play a great role as an antioxidant factor as indicated by increasing GSH level and reduce MDA level.

Partial Purification and Characterization of Rhodanese from Rainbow Trout (Oncorhynchus mykiss) Liver

Cyanide is one of the most toxic substances present in a wide variety of food materials that are consumed by animals. Rhodanese, a ubiquitous enzyme, can catalyse the detoxification of cyanide by sulphuration reaction. In this study, rhodanese was partially purified and characterized from the liver tissue homogenate of the rainbow trout. The enzyme was active in a broad range of pH, from 5 to 12. The optimal activity was found at a high pH (pH 10.5), and the temperature optimum was25∘C. The enzyme was heat labile, losing > 50% of relative activity after only 5 min of incubation at40∘C. TheKmvalues for KCN and Na2S2O3as substrates were 36.81 mM and 19.84 mM, respectively. Studies on the enzyme with a number of cations showed that the activity of the enzyme was not affected by Sn2+, but Hg2+, Ba2+, Pb2+, and Ca2+inhibited and Cu2+activated the enzyme with a concentration-dependent manner.

An h.p.l.c. assay for protoporphyrinogen oxidase activity in rat liver

An h.p.l.c. method is described for the assay of protoporphyrinogen oxidase activity in rat liver. A relatively pure protoporphyrinogen IX substrate was obtained by selectively removing any protoporphyrin IX unreduced by sodium amalgam on a small disposable cartridge packed with a strong anion-exchanger. The protoporphyrin IX formed was extracted with dimethyl sulphoxide/methanol (3:7, v/v) containing mesoporphyrin as the internal standard for separation and quantification by reversed-phase chromatography. The Km for protoporphyrinogen was 9.5 +/- 1.6 microM, and the enzyme activities were 0.59 +/- 0.11 nmol of protoporphyrin IX produced/min per mg of mitochondrial protein and 33.5 +/- 2.7 nmol protoporphyrin IX produced/min per g of liver tissue homogenate. The method is applicable to the determination of enzyme activity in small amounts of human liver biopsy.

Effect of Oyster Mushroom (Pleurotus Florida) on Paracetamol Induced Changes of serum bilirubin level and liver tissue protein in Rats

Backgroud: Liver is continuously exposed to a variety of toxic agents like drugs and chemicals that may interfere with hepatic function and may cause hepatic damage. Oyster mushroom is excellently edible, nutritious and has got free radical scavenging activity, thereby may be considered as hepatoprotective agent. Objective: To observe the effect of Oyster mushroom on paracetamol induced changes in serum bilirubin and liver tissue protein in rats. Method: This experimental study was carried out in the Department of Physiology, Sir Salimullah Medical College (SSMC), Dhaka from 1st July 2009 to 30th June 2010. A total number of 34 Wistar albino rats, age ranged from 90 to 120 days, weighing between 150 to 210 grams were selected for the study. After acclimatization for 14 days, they were divided into two groups, control group (Group A) and experimental group (Group B- mushroom pretreated and paracetamol treated group). Control group was again subdivided into group A1 (baseline control) and group A2 (paracetamol treated control group). All groups of animals received basal diet for 30 consecutive days. Group A1 consisted of 10 rats, received propylene glycol (2 ml/kg bw, orally) only on 30th day. Group A2 consisted of 14 rats, received single dose of paracetamol suspension (750 mg/ kg bw, orally) only on 30th day. Group B consisted of 10 rats, received mushroom extract (200 mg/ kg bw, orally) for 30 consecutive days and paracetamol suspension (750 mg/ kg bw, orally) only on 30th day. All the animals were sacrificed on 31st day. Then blood and liver sample were collected. Estimation of serum total bilirubin level and assessment of protein concentration in liver tissue homogenate were done by using standard laboratory kits. The statistical analysis was done by one way ANOVA and Bonferroni test as applicable. Result: The mean serum total bilirubin was significantly (p< 0.001) higher in paracetamol treated group in comparison to that of baseline control group. Again, the mean serum total bilirubin was significantly (p<0.001) lower in mushroom pretreated and paracetamol treated group (experimental group) when compared to that of paracetamol treated group (control). The protein concentration in liver tissue homogenate was significantly (p<0.01) lower in paracetamol treated group in comparison to that of baseline control group. Again, in the liver tissue homogenate protein concentration was significantly (p<0.001) higher in mushroom pretreated and paracetamol treated group (experimental group) when compared to that of paracetamol treated group (control). Conclusion: The present study revealed that Oyster mushroom can protect liver tissue against paracetamol induced liver damage. Key words: Hepatoprotective; Oyster mushroom; Tissue homogenate DOI: http://dx.doi.org/10.3329/jbsp.v6i1.8060 J Bangladesh Soc Physiol. 2011 June; 6(1): 10-15

A BIOCHEMICAL AND HISTOCHEMICAL STUDY OF GLUTAMIC OXALACETIC TRANSAMINASE ACTIVITY OF RAT HEPATIC MITOCHONDRIA FIXED IN SITU AND IN VITRO

Rat liver perfused in situ briefly with a glutaraldehyde-formaldehyde mixture was homogenized in isotonic sucrose. The mitochondria, isolated from a homogenate of the perfused liver by differential centrifugation, assumed a slender and compact appearance similar to those often seen in an intact cell. The glutamic oxalacetic transaminase (GOT) activity of this mitochondrial fraction survived an additional formaldehyde fixation and was studied by biochemical and histochemical methods. The biochemical assay of the enzyme activity revealed that the activity was only slightly less than that of an unfixed mitochondrial fraction. The reaction product due to mitochondrial GOT activity was found to be localized to the cristae, as had been demonstrated in an intact liver cell. GOT activity of the mitochondrial fraction isolated from fresh liver tissue homogenate in 0.25 M sucrose was inactivated readily by either glutaraldehyde or formaldehyde and was no longer demonstrable by biochemical and histochemical methods after fixation.