EFFECT OF OLIGOSACCHARIDES ON ENZYMES OF CARBOHYDRATE METABOLISM AND ANTIOXIDANT PROTECTION IN IN VITRO TREATED ERYTHROCYTES UNDER CONDITIONS OF HYPERGLYCEMIA

Introduction: The purpose of this experiment is to examine the effect of different oligosaccharides with proven prebiotic effects on enzymes of carbohydrate metabolism and the antioxidant protection of erythrocytes in vitro under conditions of hyperglycemia. Materials and methods: This experiment included 10 healthy men (27±3 years of age). The isolated erythrocytes were treated with 1% and 5% solutions of the following oligosaccharides: lactulose, inulin, galactooligosaccharide and fructooligosaccharide in the presence of 5mM, 50mM and 100mM glucose. After incubation, for 2 hours at 37 °C, the erythrocytes were lysed, and the supernatant was used for analyses of lactate dehydrogenase, hexokinase and glutathione reductase. FRAP (Ferric reducing antioxidant power) method was used for determining the total antioxidant activity of erythrocytes. Results: Lactate dehydrogenase was decreased in the presence of 5% lactulose in groups with 50mM and 100 mM Glc. An increase in the activity of glutathione reductase under severe hyperglycemia (100mM glucose) was observed after treatment with: 1% lactulose, 1% inulin, 1% galactooligosaccharide, 1% and 5% fructooligosaccharides (p<0.005). A significant difference in the enzymatic activity of hexokinase was found in all groups (p<0.05) and of glutathione reductase only in the control group as well as in the groups treated with 1% lactulose, 1% galactooligosaccharide, 1% and 5% fructooligosaccharides Conclusions: Galactooligosaccharides 1% and fructooligosaccharides 1% and 5% cause a statistically significant increase of the enzymatic activities of hexokinase and glutathione reductase in in vitro hyperglycemia induced by 100 mM glucose, as well as an increase in FRAP.

​Impact of Extreme Hot Environmental Temperature Period on Marker Enzymes of Carbohydrate Metabolism in Non-descript Sheep from Arid Tracts of Rajasthan

Background: The present investigation was envisaged to find out the impact of extreme hot environmental temperature period (ETP) on marker enzymes of carbohydrate metabolism in male and female non-descript sheep of various age groups i.e. 4 to 13 months from arid tracts of Rajasthan. Glucose-6-phosphate dehydrogenase (G-6-PDH) and malate dehydrogenase (MDH) marker enzymes of carbohydrate metabolism were considered for study. Methods: During the period October 2016-June 2017 blood samples were collected to harvest sera for spectrophotometric method from 240 healthy animals selected from private slaughter house during moderate and extreme hot environmental temperature periods (ETPs). The mean values of markers attained during moderate ETP were reckoned as the control. It was 10.00 ± 0.10 UL-1 and 42.00±1.00 respectively. Conclusion: The mean value of MDH was significantly (p≤0.05) higher while G-6-PDH significantly (p≤0.05) lowers during extreme hot temperature in comparison to moderate period. Therefore, it could be concluded that variations in enzyme markers were associated with changes in environmental temperatures. Probably ETP were able to produce a profound effect on carbohydrate metabolism in sheep. Therfore it can be suggested that during the period of extreme temperature balanced ration must be provided to the animal along with proper management to decrease the severity of temperature impact.

Sub-fractions from Carica Papaya Seed Extracts Can Prevent Potassium Bromate- induced Changes in Activities of Renal Brush Border Membrane Enzymes and Some Enzymes of Carbohydrate Metabolism in the Kidney of Rats

Aim: To investigate the effect of the chromatographic fractions of Carica papaya seed on KBrO3 –induced reduction in the activities of renal brush border membrane (BBM) marker enzymes and the changes in activities of some enzymes of carbohydrate metabolism in the kidney of rats. Study Design: twenty male Wistar rats were divided into four groups, five rats per group; normal control, KBrO3 control, papaya fraction control and KBrO3 group administered with 126mg/kg body weight of the most active fraction of partially purified methanol extract of C. papaya for 48 hours. Place and Duration of Study: Department of Biochemistry Laboratory, Faculty of Basic Medical Sciences, Bayero University Kano, Nigeria. Methodology: The activities of renal BBM marker enzymes: γ-glutamyl transferase, alkaline phosphatase, maltase and leucine aminopeptidase were assayed in homogenates of renal cortex and medulla, and in brush border membrane vesicle (BBMV) isolated from cortex using standard methods. Furthermore, activities of the following enzymes representing different pathways of carbohydrate metabolism were determined in renal homogenates: hexokinase (HK), lactate dehydrogenase (LDH), malate dehydrogenase (MDH), glucose 6-phosphatase (G6P), fructose 1,6-bisphosphatase (FBP), glucose 6-phosphate dehydrogenase (G6PD) and malic enzyme (ME). Results: KBrO3 administration significantly (P<0.05) decreases the activities of all the BBM marker enzymes in renal homogenates and BBMV. It also decreases the activities of MDH, G6P, FBP and G6PD, and significantly increases (P<0.05) that of HK, LDH and ME in renal homogenates however co-administration of most active fraction of C. papaya seed prevented all the KBrO3 -induced changes in these biochemical parameters. Conclusion: Chromatographic fractions of C. papaya seed extract possesses potent phytochemicals that could prevent KBrO3 –induced reduction in activities of renal BBM marker enzymes and the changes in enzymes of carbohydrate metabolism studied and therefore could be analyzed further to isolate the bioactive compounds.

AM-Induced Alteration in the Expression of Genes, Encoding Phosphorus Transporters and Enzymes of Carbohydrate Metabolism in Medicago lupulina

Plant–microbe interactions, including those of arbuscular mycorrhiza (AM), have been investigated for a wide spectrum of model plants. The present study focuses on an analysis of gene expression that encodes phosphate and sugar transporters and carbohydrate metabolic enzymes in a new model plant, the highly mycotrophic Medicago lupulina MLS-1 line under conditions of phosphorus deficiency and inoculation with Rhizophagus irregularis. Expression profiles were detected by RT-PCR at six plant stages of development (second leaf, third leaf, shooting, axillary shoot branching initiation, axillary shoot branching, flowering initiation). In comparison to control (without AM), the variant with AM inoculation exhibited a significant elevation of transcription levels of carbohydrate metabolic enzymes (MlSUS, MlHXK1) and sucrose transporters (MlSUC4) in M. lupulina leaves at the shooting stage. We suggest that this leads to a significant increase in the frequency of AM infection, an abundance of mycelium in roots and an increase in AM efficiency (which is calculated by the fresh weight of aerial parts and roots at the axillary shoot branching initiation stage). In roots, the specificity of MlPT4 and MlATP1 gene expressions were revealed for effective AM symbiosis. The level of MlPT4 transcripts in AM roots increased more than tenfold in comparison to that of non-specific MlPT1 and MlPT2. For the first time, MlPT1 expression was shown to increase sharply against MlPT2 in M. lupulina roots without AM at the shooting initiation stage. A significant increase in MlRUB expression was revealed at late stages in the host plant’s development, during axillary shoot branching and flowering initiation. The opposite changes characterized MlHXK1 expression. Alteration in MlHXK1 gene transcription was the same, but was more pronounced in roots. The obtained results indicate the importance of genes that encode phosphate transporters and the enzymes of carbohydrate metabolism for effective AM development at the shooting stage in the host plant.