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Levels of plasma testosterone, antioxidants and oxidative stress in alcoholic patients attending de-addiction centre
Sameer R Kulkarni,K Pratibha Ravindra,CY Dhume,P Rataboli
Biology and Medicine , 2009,
Abstract: In men chronic heavy drinking interferes with reproductive hormones which are responsible for sexual maturation,sperm development and fertility. Alcohol is directly toxic to the testes; causing reduced testosterone levels.Thepresent study was designed with an aim to elucidate the effect of oxidative stress on plasma testosterone level andhypothalamic pituitary gonadal (HPG) axis function in alcoholics. The plasma testosterone, luteinizing hormone andfollicle stimulating hormone were investigated in alcohols (n=200) (25–45 years) and were compared with normal nonalcoholic controls (n=160). Alcohol abusers displayed significantly lower levels of plasma testosterone, luteinizinghormone, follicle stimulating hormone, Vitamin C, Vitamin E, - Carotene, Glutathione and Superoxide Dismutase,Glutathione Reductase activities accompanied with significantly higher levels of Protein carbonyl content andMalondialdehyde levels than controls (P<0.001).Decreased serum testosterone level in alcoholics might be due toincreased oxidative stress and decrease in antioxidant levels.
Plant Polyphenol Antioxidants and Oxidative Stress
URQUIAGA,INES; LEIGHTON,FEDERICO;
Biological Research , 2000, DOI: 10.4067/S0716-97602000000200004
Abstract: in recent years there has been a remarkable increment in scientific articles dealing with oxidative stress. several reasons justify this trend: knowledge about reactive oxygen and nitrogen species metabolism; definition of markers for oxidative damage; evidence linking chronic diseases and oxidative stress; identification of flavonoids and other dietary polyphenol antioxidants present in plant foods as bioactive molecules; and data supporting the idea that health benefits associated with fruits, vegetables and red wine in the diet are probably linked to the polyphenol antioxidants they contain.in this review we examine some of the evidence linking chronic diseases and oxidative stress, the distribution and basic structure of plant polyphenol antioxidants, some biological effects of polyphenols, and data related to their bioavailability and the metabolic changes they undergo in the intestinal lumen and after absorption into the organism.finally, we consider some of the challenges that research in this area currently faces, with particular emphasis on the contributions made at the international symposium "biology and pathology of free radicals: plant and wine polyphenol antioxidants" held july 29-30, 1999, at the catholic university, santiago, chile and collected in this special issue of biological research
Plant Polyphenol Antioxidants and Oxidative Stress
INES URQUIAGA,FEDERICO LEIGHTON
Biological Research , 2000,
Abstract: In recent years there has been a remarkable increment in scientific articles dealing with oxidative stress. Several reasons justify this trend: knowledge about reactive oxygen and nitrogen species metabolism; definition of markers for oxidative damage; evidence linking chronic diseases and oxidative stress; identification of flavonoids and other dietary polyphenol antioxidants present in plant foods as bioactive molecules; and data supporting the idea that health benefits associated with fruits, vegetables and red wine in the diet are probably linked to the polyphenol antioxidants they contain.In this review we examine some of the evidence linking chronic diseases and oxidative stress, the distribution and basic structure of plant polyphenol antioxidants, some biological effects of polyphenols, and data related to their bioavailability and the metabolic changes they undergo in the intestinal lumen and after absorption into the organism.Finally, we consider some of the challenges that research in this area currently faces, with particular emphasis on the contributions made at the International Symposium "Biology and Pathology of Free Radicals: Plant and Wine Polyphenol Antioxidants" held July 29-30, 1999, at the Catholic University, Santiago, Chile and collected in this special issue of Biological Research
Oxidative stress and antioxidants in hepatic pathogenesis  [cached]
Hye-Lin Ha, Hye-Jun Shin, Mark A Feitelson, Dae-Yeul Yu
World Journal of Gastroenterology , 2010,
Abstract: Long term hepatitis B virus (HBV) infection is a major risk factor in pathogenesis of chronic liver diseases, including hepatocellular carcinoma (HCC). The HBV encoded proteins, hepatitis B virus X protein and preS, appear to contribute importantly to the pathogenesis of HCC. Both are associated with oxidative stress, which can damage cellular molecules like lipids, proteins, and DNA during chronic infection. Chronic alcohol use is another important factor that contributes to oxidative stress in the liver. Previous studies reported that treatment with antioxidants, such as curcumin, silymarin, green tea, and vitamins C and E, can protect DNA from damage and regulate liver pathogenesis-related cascades by reducing reactive oxygen species. This review summarizes some of the relationships between oxidative stress and liver pathogenesis, focusing upon HBV and alcohol, and suggests antioxidant therapeutic approaches.
OXIDATIVE STRESS, STRESS PROTEINSAND ANTIOXIDANTS IN EXERCISE
Dragan Radovanovi?,Goran Rankovi?
Acta Medica Medianae , 2004,
Abstract: Exercise appears to increase reactive oxygen species (ROS), which can result in damage to cells. Potential sources of ROS in skeletal muscle fibers during exercise include the mitochondrial respiratory chain, xantine oxidase production of superoxide, enzymatic arachidonic acid oxygenation, nitric oxide synthesis, catecholamine oxidation, and neutrophil-induced oxidative burts. Stress proteins (SPs) represent one of the general molecular protective mechanisms that enable cell and whole organisms to survive stress. The exact relationship between exercise, ROS and SPs remains unclear. Antioxidant supplements have been touted by manufacturers as a means for athletes to perform better, recover more quickly and fully from endurance exercise, or allow them to train more strenuously. At present, data are insufficient to recommend antioxidant supplements for athletes or other persons who exercise regularly. However, no one questions the importance of ingesting a diet rich in antioxidants for all who exercise and train regularly.
Role of Oxidative Stress and Antioxidants in Children with IDA
Parasuram Melarcode Krishnamoorthy,Natesh Prabu R,Mohan D.M,Sabitha N
International Journal of Collaborative Research on Internal Medicine & Public Health , 2010,
Abstract: Background: Increased oxidative stress with free radical generation in iron deficiency anemia (IDA), its aggravation at therapeutic doses of iron and reduction of oxidative stress by antioxidant supplementation are well studied in adults. Studies in this regard are scanty in children. Objective: The co-prescription of antioxidants with iron supplementation in IDA to counter the oxidative stress is a well studied and established fact in adults .Though iron supplementation is a common clinical practice in children it is not conventional to co-prescribe anti-oxidants in children. Therefore a study was undertaken to evaluate the oxidative stress in IDA in children and the effect of antioxidants during iron supplementation and to evolve an optimal suitable therapeutic strategy to minimize oxidative stress and there by adverse clinical effects. Methods: All the children attending the pediatrics OPD in IRT PMCH during JULY/AUGUST 2008 were randomly screened for anemia by clinical and hemoglobin evaluation. 21 children whose parents gave consent for participation in the study were included for evaluation. They were in the age group of ten months to sixteen years. Nutritional status of the study population was recorded by a twenty four hour recall survey method. After deworming, children were started with oral iron supplementation in three different groups; group I – oral iron only, group II – oral iron with vitamin C, group III – oral iron with vitamin E. Lipid peroxides and Lipid hydroperoxides were measured as the indices of oxidative stress before initiation, tenth day (I follow up), thirtieth day (II follow up) after oral iron therapy. Serum iron profile was also studied for evaluation. Results: There was no significant difference in serum iron profile response to oral iron therapy between the groups. Oxidative stress indices showed a decreasing trend in all the groups with no significant difference among the groups. There were no clinical adverse effects of oral iron supplementation in all the groups. Conclusion: Unlike in adults, oxidative stress in iron deficiency anemia is not aggravated by oral iron supplementation in children. There was no significant difference between oral iron alone and oral iron with antioxidants in terms of clinical and biochemical response. Lipid hydroperoxides seems to be an early indicator of oxidative stress.
Impacts of Oxidative Stress and Antioxidants on Semen Functions  [PDF]
Amrit Kaur Bansal,G. S. Bilaspuri
Veterinary Medicine International , 2011, DOI: 10.4061/2011/686137
Abstract: Oxidative stress (OS) has been considered a major contributory factor to the infertility. Oxidative stress is the result of imbalance between the reactive oxygen species (ROS) and antioxidants in the body which can lead to sperm damage, deformity, and eventually male infertility. Although high concentrations of the ROS cause sperm pathology (ATP depletion) leading to insufficient axonemal phosphorylation, lipid peroxidation, and loss of motility and viability but, many evidences demonstrate that low and controlled concentrations of these ROS play an important role in sperm physiological processes such as capacitation, acrosome reaction, and signaling processes to ensure fertilization. The supplementation of a cryopreservation extender with antioxidant has been shown to provide a cryoprotective effect on mammalian sperm quality. This paper reviews the impacts of oxidative stress and reactive oxygen species on spermatozoa functions, causes of ROS generation, and antioxidative strategies to reduce OS. In addition, we also highlight the emerging concept of utilizing OS as a tool of contraception. 1. Introduction Gametes are susceptible to reactive oxygen species (ROS) attack. When manipulated in vitro during assisted reproductive techniques, these cells run the risk of generating and being exposed to supra-physiological level of ROS [1]. Defective sperm functions are the most prevalent causes of male infertility and a difficult condition to treat [2]. Many environmental, physiological, and genetic factors have been implicated in the poor sperm functions and infertility [3–6]. Thus, it is very important to identify the factors/conditions which affect normal sperm functions. Among various causes, oxidative stress (OS) has been attributed to affect the fertility status and physiology of spermatozoa [7]. The term oxidative stress is generally applied when oxidants outnumber antioxidants [1]. The imbalance between the production of reactive oxygen species (ROS) and a biological systems ability to readily detoxify the reactive intermediates or easily repair the resulting damage is known as oxidative stress [8]. The main destructive aspects of oxidative stress are the production of ROS, which include free radicals and peroxides [9]. The production of ROS by sperm is a normal physiological process, but an imbalance between ROS generation and scavenging activity is detrimental to the sperm and associated with male infertility [10]. Physiological levels of ROS influence and mediate the gametes [11–13] and crucial reproductive processes, such as sperm-oocyte
OXIDATIVE STRESS INDUCED ULCER PROTECTED BY NATURAL ANTIOXIDANTS: A REVIEW  [PDF]
Gupta Priya,Nain Parminder,Sidana Jaspreet
International Research Journal of Pharmacy , 2012,
Abstract: Oxidative stress is caused by an imbalance between the production of reactive oxygen and a biological system's ability to readily detoxify the reactive intermediates, which ultimately leads to oxidative deterioration of protein, lipid and DNA. In humans, oxidative stress is involved in pathology of many diseases, such as atherosclerosis, Parkinson’s disease, heart failure, myocardial infarction, and chronic fatigue syndrome. Reactive oxygen species (ROS) can be beneficial, as they are used by the immune system as a way to attack and kill pathogens. To counteract oxidative stress, the body produces an armory of antioxidants to defend itself. It's the job of antioxidants to neutralize free radicals that can harm the cells. Body's internal production of antioxidants is not enough to neutralize all the free radicals. It’s a well-known fact that ROS are involved in the aetio-pathogenesis of the inflammatory and ulcerative lesions of the gastrointestinal tract. The present review focuses on the studies where oxidative damage due to stress has been linked causally to loss of cell integrity mainly in peptic ulcer cured by natural antioxidants.
Reduction in hypercholesterolemia and risk of cardiovascular diseases by mixtures of plant food extract: a study on plasma lipid profile, oxidative stress and testosterone in rats
Mohamed, Doha A.,Hamed, Thanaa E.,Al-Okbi, Sahar Y.
Grasas y Aceites , 2010, DOI: 10.3989/gya.021210
Abstract: The present study was postulated to prepare and evaluate the influence of two plant food extract mixtures on plasma lipid profile, oxidative stress and testosterone levels in rats fed a hypercholesterolemic diet. The safety of the studied extract mixtures was evaluated through the determination of liver and kidney functions. The total phenolic contents, tocopherols, fatty acids and unsaponifiable matter (UNSAP) in the extract mixtures were determined. Rats fed a hypercholesterolemic diet were given a daily oral dose (300 mg/kg rat body weight) of either mixture I or II for a month and compared with a control hypercholesterolemic group and a normal control group. Results showed that α-tocopherol was 0.750 and 4.017 mg, γ-tocopherol was 0.564 mg and 0 and δ-tocopherol was 15.23mg and 0.634mg/100g for mixtures I and II, respectively. The phenolic contents in mixtures I and II were 36.74 and 23.72 g gallic acid equivalent/100g mixture, respectively. The GLC investigation of UNSAP revealed that stigmasterol and b-sitosterol were the major phytosterols in mixtures I and II, respectively followed by campesterol in both. The GLC analysis of the fatty acids showed that oleic acid was the major fatty acid in both extract mixtures. Results from the animal experiment showed that feeding a hypercholesterolemic diet produced a significant increase in total lipids, total cholesterol (T-Ch), triglycerides (TGs), low density lipoprotein cholesterol (LDLCh), T-Ch/HDL-Ch, TGs/HDL-Ch and malondialdehyde (MDA) and a significant reduction in high density lipoprotein cholesterol (HDL-Ch), vitamin E, b-carotene and testosterone. Rats fed a hypercholesterolemic diet and given mixture I or II showed significant improvements in plasma lipid profile compared to the hypercholesterolemic control group. This improvement was associated with a significant reduction in oxidative stress reflected by an elevation in plasma levels of antioxidants (vitamin E and b-carotene) and a reduction in plasma MDA levels. The plasma level of testosterone increased significantly in the rats fed the hypercholesterolemic diet and given mixture I or II compared to the hypercholesterolemic control. Plasma testosterone showed a significant negative correlation with plasma TGs and TGs/HDL-Ch in the hypercholesterolemic control rats. The studied extract mixtures showed complete safety towards liver and kidney functions. In conclusion the tested extract mixtures showed an improvement in the plasma lipid profile, a significant increase in testosterone and a decrease in oxidative stress with promising prevention
Free radicals, oxidative stress and importance of antioxidants in human health  [PDF]
Amit Kunwar,K.I. Priyadarsini
Journal of Medical and Allied Sciences , 2011,
Abstract: Reactive oxygen species (ROS) is a collective term used for oxygen containing free radicals, depending on their reactivity and oxidizing ability. ROS participate in a variety of chemical reactions with biomolecules leading to a pathological condition known as oxidative stress. Antioxidants are employed to protect biomolecules from the damaging effects of such ROS. In the beginning, antioxidant research was mainly aimed at understanding free radical reactions of ROS with antioxidants employing biochemical assays and kinetic methods. Later on, studies began to be directed to monitor the ability of anti-oxidants to modulate cellular signaling proteins like receptors, secondary messengers, transcription factors, etc. Of late several studies have indicated that antioxidants can also have deleterious effects on human health depending on dosage and bio-availability. It is therefore, necessary to validate the utility of antioxidants in improvement of human health in order to take full advantage of their therapeutic potential.
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