Protective effect of polypeptides from larva of housefly (Musca domestica) on hydrogen peroxide-induced oxidative damage in HepG2 cells

Housefly (Musca domestica) is an important medical insect and its larva is an ideal high protein food source. We isolated from housefly larvae the polypeptides hydrolyzed by neutral protease (PHNP), and investigated the protective effect of PHNP on hydrogen peroxide (H₂O₂)-induced oxidative damage in HepG2 cells. Cells exposed to H₂O₂ showed a marked decrease in proliferation and intracellular superoxide dismutase (SOD) activity, and a significant increase in reactive oxygen species (ROS) level and malondialdehyde (MDA) content. H₂O₂ also caused apoptosis and mitochondrial dysfunction including mitochondrial fragmentation and the loss of mitochondrial membrane potential. Pretreatment with PHNP at concentrations of 2.5, 5, 10 μg/mL blocked these H₂O₂-induced cellular events in a dose-dependent manner. The effect of PHNP at 10 μg/mL is equal to that of ascorbic acid at 10 μM. In summary, PHNP has a protective effect against H₂O₂-induced oxidative injury in cells due to its ability to decrease intracellular ROS and elevate antioxidant enzyme activities.     

Wound healing effect of flavonoid rich fraction and luteolin isolated from Martynia annua Linn. on streptozotocin induced diabetic rats

ObjectiveTo evaluate wound healing potential of flavonoid fractions of Martynia annua (M. annua) Linn. leaves in diabetic rats on the basis of folkloric information and preliminary study.MethodsThe flavonoid compound luteolin and apigenin were isolated from dried leaves of plant by column chromatography. The two concentrations (0.2% and 0.5% w/w) of luteolin and flavonoid fraction were selected for topically applied as ointment on diabetic wound. The Povidone Iodine Ointment USP was used as a reference. On 18th days, protein content, hydroxyproline and antioxidants (SOD, CAT and GSH) level in granuloma tissues were determined.ResultsThe results showed that, percent wound contraction were observed significantly (P<0.01) greater in MAF fraction and 0.5% w/w of luteolin treatment groups. Presence of matured collagen fibres and fibroblasts with better angiogenesis were observed in histopathological studies.ConclusionsIn conclusion, our findings suggest that flavonoid fraction (MAF) and luteolin (0.5% w/w) may have potential benefit in enhancing wound healing in diabetic condition, possibly due to free-radical scavenging activity of plant.     

Are antioxidant enzymes essential markers in the diagnosis and monitoring of cancer patients – A review

Reactive oxygen species (ROS) play a significant role in human cells. Excessive ROS production damages important macromolecules such as nucleic acids and can initiate and develop the carcinogenesis process. Antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), and xanthine oxidoreductase (XOR) are responsible for maintaining the balance between the functions of free radical formation and eliminating their excessive amounts.Based on the analyzed literature, the following conclusions can be made:1. Antioxidant enzymes activity are important for diagnosing neoplastic diseases such as non-small-cell lung cancer, bladder cancer, ovarian cancer, and colon cancer.2. Non-small-cell lung cancer is usually characterized by decreased SOD and CAT activity and increased glutathione GST activity. Lowered SOD, CAT, and GPx activity is characteristic of bladder cancer. XOR, CAT, SOD and GPx expression is decreased in patients with ovarian cancer. Colorectal cancer is characterized by increased MnSOD expression (in vitro studies) and SOD expression while CAT, GPx, and GR are decreased (in vivo study).3. SOD, CAT, and XOR are promising prognostic markers in cancer of the lung, bladder, ovarian, and colon.     

El entrenamiento en tapiz rodante a domicilio mejora la calidad seminal en adultos con diabetes de tipo 2

ObjectiveThis was the first study conducted to determine the influence of home-based treadmill training on seminal quality in adults with type 2 diabetes.Material and methodsSixty sedentary adults with type 2 diabetes volunteered for the current study. Thirty were randomly allocated to the intervention group and performed a a 14-week, home-based, treadmill training program, 3 sessions per week, consisting of a warm-up (10-15 min), 40 min treadmill exercise at a work intensity of 55-70% of peak heart rate (increasing by 2.5% each two weeks) measured during a maximal treadmill test, and cooling-down (5-10 min). The control group included 30, age and BMI matched adults with type 2 diabetes who did not take part in any training program. Seminal quality analysis included semen volume, sperm concentration, motility and normal morphologic features. Furthermore, total antioxidant status (TAS) as well as glutathione peroxidase (GPX) activity were assessed in seminal plasma. This protocol was approved by an Institutional Ethics Committee.ResultsThe home-based treadmill training significantly increased sperm concentration as well as percentages of total sperm motility and normal spermatozoa. Furthermore, TAS and GPX activity were increased after the completion of the training program. No significant changes in any of the measured variables were found in the control group.ConclusionsHome-based treadmill training improved seminal quality in adults with type 2 diabetes. A secondary finding was that seminal antioxidant defense system was significantly increased after being exercised.     

Oxidative stress in benign prostate hyperplasia

To assess the status of oxidative stress in benign prostate hyperplasia, a very common disease in older men which constitutes a public health problem in Jijel, prostate tissues were obtained by transvesical adenomectomy from 10 men with benign prostate hyperplasia. We measured the cytosolic levels of malondialdehyde (MDA) and glutathione (GSH) and cytosolic enzyme activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione S‐transferase. The development of benign prostate hyperplasia is accompanied by impaired oxidative status by increasing levels of MDA, depletion of GSH concentrations and a decrease in the activity of all the antioxidant enzymes studied. These results have allowed us to understand a part of the aetiology of benign prostate hyperplasia related to oxidative stress.     

Uncertainty of antioxidant profiling in complex mixtures using liquid chromatography involving post-column derivatisation

The main goal of this paper is to discuss the problems associated with antioxidant profiling in complex samples using a high-throughput HPLC system coupled with post-column derivatisation reactor. Based on the experimental data reported in the literature, we demonstrated that improper optimisation of temperature and/or pH assay conditions performed using an on-line derivatisation reactor may substantially change the antioxidant peaks ratio of targeted phytochemical compounds. It has been found that despite the relatively high stability of flavonoids at high temperature and under binary mobile phase HPLC conditions, the reaction of target compounds with common ABTS, FCR and DPPH radicals at elevated regions (particularly above 100 °C) dramatically changes their antioxidant activity values expressed, for example, as TEAC (Trolox equivalent antioxidant capacity) parameters. In principle, separation and detection processes of antioxidant profiling assay must not significantly affect the antioxidant activity of target compounds. In the case of foods eaten by humans or animals, critical experimental parameters such as pH and temperature concerning interaction of target analytes with derivatisation reagent should be as close as possible to the real physiological values.     

Starch-quercetin conjugate by radical grafting: synthesis and biological characterization

A novel flavonoid-polysaccharide conjugate was synthesized by free radical grafting of quercetin on starch. The covalent insertion of quercetin in the polymeric chain was confirmed by FT-IR, DSC and fluorescence analyses, while an estimation of the amount of quercetin bound per g of polymer was obtained by the Folin-Ciocalteu assay. The conjugate shows improved UV stability and retains the antioxidant properties of free quercetin, such as scavenging activity towards free radicals (DPPH and peroxynitrite); inhibition of the free radical formation (peroxidation of linoleic acid) and total antioxidant activity. The conjugate also prevented drug degradation and shows potential health functionality in the treatment of Alzheimer disease, diabetes and as skin-whitening agent.     

In vitro human colonic fermentation of indigestible fraction isolated from lunch menus: impact on the gut metabolites and antioxidant capacity

The indigestible fraction (IF) isolated from three lunch menus: Modified Mexican Lunch (MM-L), Traditional Mexican Lunch (TM-L) and Alternative Mexican Lunch (AM-L), was studied in terms of antioxidant capacity (AOX) and metabolites produced through fermentation by human intestinal microbiota. IFs were isolated after withstanding in vitro gastrointestinal digestion and total soluble polyphenols (TSP), condensed tannins (CT), hydrolysable polyphenols (HP) and AOX (DPPH, FRAP) were evaluated. AOX, pH and bacterial metabolites profile changes were also monitored during in vitro colonic fermentation. Lunch menus showed differences in IF, TSP, CT and FRAP values (p<.05). TM-L had the highest TSP and CT contents (0.84 and 1.89?g/100?g DW, respectively). Changes in pH and AOX during fermentation were time-dependent and substrate-dependent (p<.05). Butyric acid production was not significantly modified by the IFs (p>.05). Fifty-seven microbiota-produced volatile compounds were detected by SPME-GC–MS. This study shows the potential effects of food habits on bacterial metabolite production.     

Antioxidative Potential of Duranta Repens (Linn.) Fruits Against H2O2 Induced Cell Death In Vitro

The effects of Duranta repens fruits were investigated on H₂O₂ induced oxidative cell death to evaluate its antioxidative potential in vitro. HEK293T cells were treated with different concentrations [0–1000 µg/ ml] of ethanol extract (E-Ex) and methanol extract (M-Ex) of D. repens for 24h, and then treated with 100 µM H₂O₂ for 24h. Cell viability, antioxidant parameters of cells, and antioxidant constituents of the extracts were determined. Treatment with limited dose of E-Ex or M-Ex increased the survival rate of H₂O₂-treated HEK293T cells, however the extra-high dose showed growth inhibitory effect. Treatment with E-Ex or M-Ex protected cellular lipid per-oxidation. In vitro analyses showed the 2,2-diphenyl-1-picrylhydrazyl and H₂O₂ scavenging activities as well as reducing potential of the extracts. We report here that the limited dose of E-Ex and M-Ex possess antioxidative potential, which can protect H₂O₂-induced oxidative cell damage.