Protective mechanisms of Cucumis sativus in diabetes-related modelsof oxidative stress and carbonyl stress

Metabolic activation of 2,4,6-trinitrotoluene; a case for ROS-induced cell damage

The explosive compound 2,4,6-trinitrotoluene (TNT) is well known as a major component of munitions. In addition to its potential carcinogenicity and mutagenicity in humans, recent reports have highlighted TNT toxicities in diverse organisms due to its occurrence in the environment. These toxic effects have been linked to the intracellular metabolism of TNT, which is generally characterised by redox cycling and the generation of noxious reactive molecules. The reactive intermediates formed, such as nitroso and hydroxylamine compounds, also interact with oxygen molecules and cellular components to cause macromolecular damage and oxidative stress. The current review aims to highlight the crucial role of TNT metabolism in mediating TNT toxicity, via increased generation of reactive oxygen species. Cellular proliferation of reactive species results in depletion of cellular antioxidant enzymes, DNA and protein adduct formation, and oxidative stress. While TNT toxicity is well known, its ability to induce oxidative stress, resulting from its reductive activation, suggests that some of its toxic effects may be caused by its reactive metabolites. Hence, further research on TNT metabolism is imperative to elucidate TNT-induced toxicities.

Effects of Crocus sativus and its constituent, safranal, and pioglitazone, on systemic inflammation and oxidative stress induced by paraquat aerosol in rats

Objectives

The effects of Crocus sativus, safranal, and pioglitazone on aerosolized paraquat (PQ)-induced systemic changes were examined.

Materials and Methods

Control (Ctrl) and PQ groups of rats were exposed to saline or PQ (27 and 54 mg/m3, PQ-L and PQ-H) aerosols eight times on alternate days. Nine PQ-H groups were treated with dexamethasone (0.03 mg/kg/day, Dexa), two doses of C. sativus extract (20 and 80 mg/kg/day, CS-L and CS-H), safranal (0.8 and 3.2 mg/kg/day, Saf-L and Saf-H), pioglitazone (5 and 10 mg/kg/day, Pio-L and Pio-H), and the combination of low dose of the pioglitazone and extract or safranal (Pio + CS and Pio + Saf) after the end of PQ exposure.

Results

Interferon-gamma (INF-γ), interleukin 10 (IL-10), superoxide dismutase (SOD), catalase (CAT), and thiol serum levels were reduced, but tumor necrosis factor (TNF-α), malondialdehyde (MDA), and total and differential WBC were increased in both PQ groups (P<0.05 to P<0.001). All measured variables were improved in all treated groups (P<0.05 to P<0.001). The effects of high dose of C. sativus and safranal on measured parameters were higher than dexamethasone (P<0.05 to P<0.001). The effects of Pio + CS and Pio + Saf treatment on most variables were significantly higher than three agents alone (P<0.05 to P<0.001).

Conclusion

C. sativus and safranal improved inhaled PQ-induced systemic inflammation and oxidative stress similar to those of dexamethasone and showed synergic effects with pioglitazone suggesting the possible PPARγ receptor-mediated effects of the plant and its constituent.

Spinach consumption and nonalcoholic fatty liver disease among adults: a case-control study

BACKGROUND

Spinach has high antioxidants and polyphenols and showed protective effects against liver diseases in experimental studies. We aimed to assess the association between dietary intake of spinach and odds of nonalcoholic fatty liver disease (NAFLD) in a case-control study among Iranian adults.

METHODS

Totally 225 newly diagnosed NAFLD patients and 450 controls, aged 20-60 years, were recruited in this study. Participants' dietary intakes were collected using a valid and reliable 168-item semi-quantitative food frequency questionnaire (FFQ). The logistic regression test was used for assessing the association between total, raw, and boiled dietary spinach with the odds of NAFLD.

RESULTS

The mean (SD) age and BMI of participants (53% male) were 38.1 (8.8) years and 26.8 (4.3) kg/m², respectively. In the final adjusted model for potential confounders, the odds (95% CI) of NAFLD in individuals in the highest tertile of daily total and raw spinach intake was [0.36 (0.19-0.71), P_trend = 0.001] and [0.47 (0.24-0.89), P_trend = 0.008], respectively compared with those in the lowest tertile. Furthermore, in the adjusted analyses, an inverse association was observed between the highest yearly intake versus no raw spinach consumption and odds of NAFLD [(OR 0.41; 95% CI 0.18-0.96), P for trend = 0.013]. However, there was no significant association between higher boiled spinach intake and odds of NAFLD.

CONCLUSIONS

The present study found an inverse association between total and raw spinach intake with the odds of NAFLD.

Oxymatrine Ameliorates Memory Impairment in Diabetic Rats by Regulating Oxidative Stress and Apoptosis: Involvement of NOX2/NOX4

Oxymatrine (OMT) is the major quinolizidine alkaloid extracted from the root of Sophora flavescens Ait and has been shown to exhibit a diverse range of pharmacological properties. The aim of the present study was to investigate the role of OMT in diabetic brain injury in vivo and in vitro. Diabetic rats were induced by intraperitoneal injection of a single dose of 65 mg/kg streptozotocin (STZ) and fed a high-fat and high-cholesterol diet. Memory function was assessed using a Morris water maze test. A SH-SY5Y cell injury model was induced by incubation with glucose (30 mM/l) to simulate damage in vitro. The serum fasting blood glucose, insulin, serum S100B, malondialdehyde (MDA), and superoxide dismutase (SOD) levels were analyzed using commercial kits. Morphological changes were observed using Nissl staining and electron microscopy. Cell apoptosis was assessed using Hoechst staining and TUNEL staining. NADPH oxidase (NOX) and caspase-3 activities were determined. The effects of NOX2 and NOX4 knockdown were assessed using small interfering RNA. The expression levels of NOX1, NOX2, and NOX4 were detected using reverse transcription-quantitative PCR and western blotting, and the levels of caspase-3 were detected using western blotting. The diabetic rats exhibited significantly increased plasma glucose, insulin, reactive oxygen species (ROS), S-100B, and MDA levels and decreased SOD levels. Memory function was determined by assessing the percentage of time spent in the target quadrant, the number of times the platform was crossed, escape latency, and mean path length and was found to be significantly reduced in the diabetic rats. Hyperglycemia resulted in notable brain injury, including histological changes and apoptosis in the cortex and hippocampus. The expression levels of NOX2 and NOX4 were significantly upregulated at the protein and mRNA levels, and NOX1 expression was not altered in the diabetic rats. NOX and caspase-3 activities were increased, and caspase-3 expression was upregulated in the brain tissue of diabetic rats. OMT treatment dose-dependently reversed behavioral, biochemical, and molecular changes in the diabetic rats. In vitro, high glucose resulted in increases in reactive oxygen species (ROS), MDA levels, apoptosis, and the expressions of NOX2, NOX4, and caspase-3. siRNA-mediated knockdown of NOX2 and NOX4 decreased NOX2 and NOX4 expression levels, respectively, and reduced ROS levels and apoptosis. The results of the present study suggest that OMT alleviates diabetes-associated cognitive decline, oxidative stress, and apoptosis via NOX2 and NOX4 inhibition.

The effect of Malus doumeri leaf flavonoids on oxidative stress injury induced by hydrogen peroxide (H2O2) in human embryonic kidney 293 T cells

BACKGROUND

In this study, Malus doumeri leaf flavonoids (MDLF) were used as the research object to observe their in vitro antioxidant stress ability. Hydrogen peroxide (H2O2) was used to induce oxidative stress in 293 T cells.

METHODS

MTT, flow cytometry, and qPCR were used to verify the effect of MDLF.

RESULTS

In vitro cell experiments showed that at a concentration of 0-160 μg/mL, MDLF did not affect the normal proliferation of human embryonic kidney 293 T cells (HEK 293 T cells), and MDLF had no cytotoxic effect in this concentration range. It was found that MDLF could maintain the survival of HEK 293 T cells (82.6%) at a high concentration (160 μg/mL). Morphological observation also found that MDLF can inhibit the cell structure imperfection caused by H2O2. It was also observed that MDLF could significantly increase the levels of catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GSH-Px) and reduce the level of malondialdehyde (MDA). The results of quantitative polymerase chain reaction (qPCR) showed that MDLF could significantly up-regulate the mRNA expression levels of CAT, SOD, GSH, GSH-Px, B-cell lymphoma-2 (Bcl-2) and downregulate the expression levels of B-cell lymphoma-2 associated x protein (Bax), tumor necrosis factor-alpha (TNF-α), and nuclear factor kappa-B (NF-κB) in oxidative stress-injured cells. The HPLC analysis showed that MDLF contained hyperin, isoquercetin, quercitrin, hesperidin, myricetin, baicalin and quercetin.

CONCLUSION

From the experimental results, it was observed that MDLF has a strong anti-oxidation ability in vitro, and it can interfere with the oxidative stress damage caused by H2O2 in 293 T cells. Therefore, MDLF is a type of natural substance with good anti-oxidant effect, and it has the potential to interfere with many diseases.

Prophylaxis of Radiation-Induced Dermatitis in Patients With Breast Cancer Using Herbal Creams: A Prospective Randomized Controlled Trial

Radiation-induced toxicity is a major limiting factor for prescribing radiation dose in cancer radiotherapy. Skin reaction to radiation is one of the primary concerns, which could affect quality of life of the patients both physically and mentally. Reviews of the literature show limited number of effective reagents for its prophylaxis. In this study, we attempted to determine whether prophylactic treatment of the 3 different herbal creams containing Centella asiatica, Cucumis sativus, and Thunbergia laurifolia extracts as well as a commercial moisturizing cream could reduce acute skin reaction in breast cancer patients undergoing radiotherapy. A total of 153 breast cancer patients undergoing radiotherapy were randomly assigned into 5 different groups with one group receiving no treatment. The patients were instructed to apply their designated creams once daily from their first radiotherapy session until 1-month post-irradiation. Their skins were graded by a radiation oncologist on a weekly basis until 1-month post-irradiation to identify any skin reactions. The results showed that the administration of the herbal creams or the moisturizing cream could neither reduce the severity nor delay the onset of dermatitis compared with the no treatment group. However, despite the limited benefits from the prophylaxis, the Cucumis sativus cream was shown to help with the skin recovery post-irradiation. These results suggested that breast cancer patients undergoing radiotherapy should be advised to apply moisturizing cream to the area of irradiated skin.

Fruits

Fruits come in a wide variety of colors, shapes, and flavors. This chapter will cover selected fruits that are known to be healthy and highly nutritious. These fruits were chosen due to their common usage and availability. Since it is not possible to cover all health benefits or essential nutrients and important phytochemicals of the fruit composition, this chapter will focus on the key valuable constituents and their potential health effects.

Antioxidant and Oxidative Stress: A Mutual Interplay in Age-Related Diseases

Aging is the progressive loss of organ and tissue function over time. Growing older is positively linked to cognitive and biological degeneration such as physical frailty, psychological impairment, and cognitive decline. Oxidative stress is considered as an imbalance between pro- and antioxidant species, which results in molecular and cellular damage. Oxidative stress plays a crucial role in the development of age-related diseases. Emerging research evidence has suggested that antioxidant can control the autoxidation by interrupting the propagation of free radicals or by inhibiting the formation of free radicals and subsequently reduce oxidative stress, improve immune function, and increase healthy longevity. Indeed, oxidation damage is highly dependent on the inherited or acquired defects in enzymes involved in the redox-mediated signaling pathways. Therefore, the role of molecules with antioxidant activity that promote healthy aging and counteract oxidative stress is worth to discuss further. Of particular interest in this article, we highlighted the molecular mechanisms of antioxidants involved in the prevention of age-related diseases. Taken together, a better understanding of the role of antioxidants involved in redox modulation of inflammation would provide a useful approach for potential interventions, and subsequently promoting healthy longevity.

Cucumis sativus Aqueous Fraction Inhibits Angiotensin II-Induced Inflammation and Oxidative Stress In Vitro

Inflammation and oxidative stress play major roles in endothelial dysfunction, and are key factors in the progression of cardiovascular diseases. The aim of this study was to evaluate in vitro the effect of three subfractions (SFs) from the Cucumis sativus aqueous fraction to reduce inflammatory factors and oxidative stress induced by angiotensin II (Ang II) in human microvascular endothelial cells-1 (HMEC-1) cells. The cells were cultured with different concentrations of Ang II and 0.08 or 10 μg/mL of SF1, SF2, or SF3, or 10 μmol of losartan as a control. IL-6 (Interleukin 6) concentration was quantified. To identify the most effective SF combinations, HMEC-1 cells were cultured as described above in the presence of four combinations of SF1 and SF3. Then, the effects of the most effective combination on the expression of adhesion molecules, the production of reactive oxygen species (ROS), and the bioavailability of nitric oxide (NO) were evaluated. Finally, a mass spectrometry analysis was performed. Both SF1 and SF3 subfractions decreased the induction of IL-6 by Ang II, and C4 (SF1 and SF3, 10 μg/mL each) was the most effective combination to inhibit the production of IL-6. Additionally, C4 prevented the expression of adhesion molecules, reduced the production of ROS, and increased the bioavailability of NO. Glycine, arginine, asparagine, lysine, and aspartic acid were the main components of both subfractions. These results demonstrate that C4 has anti-inflammatory and antioxidant effects.