scholarly journals Structural, Chemical and Biological Aspects of Antioxidants for Strategies Against Metal and Metalloid Exposure

2009 ◽  
Vol 2 (4) ◽  
pp. 191-206 ◽  
Author(s):  
Swaran J. S. Flora
Keyword(s):  
Oxidative Stress ◽  
Chelation Therapy ◽  
Chelating Agent ◽  
Controlled Clinical Trials ◽  
Biochemical Alterations ◽  
Toxic Damage ◽  
Biological Aspects ◽  
Antioxidant Supplements ◽  
Metalloid Exposure ◽  
Dietary Flavonoids

Oxidative stress contributes to the pathophysiology of exposure to heavy metals/metalloid. Beneficial renal effects of some medications, such as chelation therapy depend at least partially on the ability to alleviate oxidative stress. The administration of various natural or synthetic antioxidants has been shown to be of benefit in the prevention and attenuation of metal induced biochemical alterations. These include vitamins, N-acetylcysteine, α-lipoic acid, melatonin, dietary flavonoids and many others. Human studies are limited in this regard. Under certain conditions, surprisingly, the antioxidant supplements may exhibit pro-oxidant properties and even worsen metal induced toxic damage. To date, the evidence is insufficient to recommend antioxidant supplements in subject with exposure to metals. Prospective, controlled clinical trials on safety and effectiveness of different therapeutic antioxidant strategies either individually or in combination with chelating agent are indispensable. The present review focuses on structural, chemical and biological aspects of antioxidants particularly related to their chelating properties.

scholarly journals Telomere Length and Oxidative Stress and Its Relation with Metabolic Syndrome Components in the Aging

Biology ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 253
Author(s):  
Graciela Gavia-García ◽  
Juana Rosado-Pérez ◽  
Taide Laurita Arista-Ugalde ◽  
Itzen Aguiñiga-Sánchez ◽  
Edelmiro Santiago-Osorio ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Metabolic Syndrome ◽  
Telomere Length ◽  
Scientific Evidence ◽  
Telomeric Dna ◽  
Biochemical Alterations ◽  
The Metabolic Syndrome ◽  
Age Related ◽  
And Function

A great amount of scientific evidence supports that Oxidative Stress (OxS) can contribute to telomeric attrition and also plays an important role in the development of certain age-related diseases, among them the metabolic syndrome (MetS), which is characterised by clinical and biochemical alterations such as obesity, dyslipidaemia, arterial hypertension, hyperglycaemia, and insulin resistance, all of which are considered as risk factors for type 2 diabetes mellitus (T2DM) and cardiovascular diseases, which are associated in turn with an increase of OxS. In this sense, we review scientific evidence that supports the association between OxS with telomere length (TL) dynamics and the relationship with MetS components in aging. It was analysed whether each MetS component affects the telomere length separately or if they all affect it together. Likewise, this review provides a summary of the structure and function of telomeres and telomerase, the mechanisms of telomeric DNA repair, how telomere length may influence the fate of cells or be linked to inflammation and the development of age-related diseases, and finally, how the lifestyles can affect telomere length.

scholarly journals Neurological Alterations and Testicular Damages in Aging Induced by D-Galactose and Neuro and Testicular Protective Effects of Combinations of Chitosan Nanoparticles, Resveratrol and Quercetin in Male Mice

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 435
Author(s):  
Reham Z. Hamza ◽  
Mohammad S. Al-Harbi ◽  
Munirah A. Al-Hazaa
Keyword(s):  
Oxidative Stress ◽  
Chitosan Nanoparticles ◽  
Oxidative Stress Marker ◽  
Control Group ◽  
Antioxidant Enzyme Activities ◽  
Enzymatic Antioxidants ◽  
Protective Effects ◽  
Biochemical Alterations ◽  
Wide Range ◽  
Neurological Alterations

Aging is a neurological disease that is afforded by incidence of oxidative stress. Chitosan has received global interests due to its wide medical uses. Quercetin (Q) is a bioflavonoid and widely distributed in vegetables and fruits. Resveratrol is considered as a potent antioxidant and is a component of a wide range of foods. The using of either chitosan nanopartciles (CH-NPs), querectin (Q), and resveratrol (RV) to reduce the oxidative stress and biochemical alterations on brain and testicular tissues induced by D-galactose (DG) (100 mg/Kg) were the aim of the present study. This study investigated the probable protective effects of CH-NPs in two doses (140,280 mg/Kg), Q (20 mg/Kg) and RV (20 mg/Kg), against DG induced aging and neurological alterations. Brain antioxidant capacity as malonaldehyde (MDA), catalase (CAT), and glutathione reductase (GRx), as well as histopathological damages of the brain and testicular tissues were measured. The DG treated group had significantly elevated the oxidative stress markers by 96% and 91.4% in brain and testicular tissues respectively and lower significantly the antioxidant enzyme activities of both brain and testicular tissues than those of the control group by 86.95%, 69.27%, 83.07%, and 69.43%. Groups of DG that treated with a combination of CH-NPs in two doses, Q and RV, the levels of oxidative stress marker declined significantly by 68.70%, 76.64% in brain tissues and by 74.07% and 76.61% in testicular tissues, and the enzymatic antioxidants increased significantly by 75.55%, 79.24%, 62.32%, and 61.97% as compared to the DG group. The present results indicate that CH-NPs, Q, and RV have protective effects against DG-induced brain and testis tissue damage at the biochemical and histopathological levels. Mechanisms of this protective effect of used compounds against neurological and testicular toxicity may be due to the enhanced brain and testis antioxidant capacities.

Effect of transfusional iron intake on response to chelation therapy in β-thalassemia major

Blood ◽  
2008 ◽  
Vol 111 (2) ◽  
pp. 583-587 ◽  
Author(s):  
Alan R. Cohen ◽  
Ekkehard Glimm ◽  
John B. Porter
Keyword(s):  
Chelation Therapy ◽  
Iron Concentration ◽  
Chelating Agent ◽  
Thalassemia Major ◽  
Phase Iii ◽  
Iron Loading ◽  
Iron Intake ◽  
Liver Iron ◽  
Iron Stores ◽  
Using Data

The success of chelation therapy in controlling iron overload in patients with thalassemia major is highly variable and may partly depend on the rate of transfusional iron loading. Using data from the 1-year phase III study of deferasirox, including volumes of transfused red blood cells and changes in liver iron concentration (LIC) in 541 patients, the effect of iron loading on achieving neutral or negative iron balance was assessed in patients receiving different doses of deferasirox and the comparator deferoxamine. After dose adjustment, reductions in LIC after 1 year of deferasirox or deferoxamine therapy correlated with transfusional iron intake. At a deferasirox dose of 20 mg/kg per day, neutral or negative iron balance was achieved in 46% and 75% of patients with the highest and lowest transfusional iron intake, respectively; 30 mg/kg per day produced successful control of iron stores in 96% of patients with a low rate of transfusional iron intake. Splenectomized patients had lower transfusional iron intake and greater reductions in iron stores than patients with intact spleens. Transfusional iron intake should be monitored on an ongoing basis in thalassemia major patients, and the rate of transfusional iron loading should be considered when choosing the appropriate dose of an iron-chelating agent. This study is registered at http://clinicaltrials.gov as NCT00061750.

scholarly journals The Role of Oxidative Stress-Induced Epigenetic Alterations in Amyloid-βProduction in Alzheimer’s Disease

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Li Zuo ◽  
Benjamin T. Hemmelgarn ◽  
Chia-Chen Chuang ◽  
Thomas M. Best
Keyword(s):  
Oxidative Stress ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Amyloid Beta ◽  
Treatment Options ◽  
Memory Loss ◽  
The United States ◽  
Traditional Medicines ◽  
Progressive Neurodegeneration ◽  
Antioxidant Supplements

An increasing number of studies have proposed a strong correlation between reactive oxygen species (ROS)-induced oxidative stress (OS) and the pathogenesis of Alzheimer’s disease (AD). With over five million people diagnosed in the United States alone, AD is the most common type of dementia worldwide. AD includes progressive neurodegeneration, followed by memory loss and reduced cognitive ability. Characterized by the formation of amyloid-beta (Aβ) plaques as a hallmark, the connection between ROS and AD is compelling. Analyzing the ROS response of essential proteins in the amyloidogenic pathway, such as amyloid-beta precursor protein (APP) and beta-secretase (BACE1), along with influential signaling programs of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and c-Jun N-terminal kinase (JNK), has helped visualize the path between OS and Aβoverproduction. In this review, attention will be paid to significant advances in the area of OS, epigenetics, and their influence on Aβplaque assembly. Additionally, we aim to discuss available treatment options for AD that include antioxidant supplements, Asian traditional medicines, metal-protein-attenuating compounds, and histone modifying inhibitors.

Anatomy of a trial

PEDIATRICS ◽  
1977 ◽  
Vol 60 (6) ◽  
pp. 932-934
Author(s):  
Neil A. Holtzman
Keyword(s):  
Clinical Trials ◽  
Clinical Situation ◽  
Enzyme Deficiency ◽  
Efficacy And Safety ◽  
Controlled Clinical Trials ◽  
Biochemical Alterations ◽  
New Treatments ◽  
The Way

Efficacy and safety of new treatments can seldom be predicted with certainty. Even when it addresses biochemical alterations, a therapy may not improve the clinical situation. The low-phenylalanine diet for phenylketonuria (PKU), for instance, followed logically from the discovery of an enzyme deficiency, but the diet's effectiveness in preventing retardation in asymptomatic infants was still in doubt a decade after it was introduced. Studies in which some subjects are not treated can often establish the benefits and risks of therapy. Many obstacles, however, lie in the way of controlled clinical trials despite the advantage they offer. The PKU story exemplifies the issues.

CRYPTIC CAUSES AND MECHANISMS INVOLVED IN AGEING

INDIAN DRUGS ◽  
2013 ◽  
Vol 50 (01) ◽  
pp. 5-22
Author(s):  
K Challabotla ◽  
◽  
D Banji ◽  
O.J.F Banji ◽  
Chilipi K Reddy
Keyword(s):  
Oxidative Stress ◽  
Developing Countries ◽  
Molecular Basis ◽  
Metabolic Disorders ◽  
Natural Process ◽  
Biological Functions ◽  
Stress Theory ◽  
Biochemical Alterations ◽  
Organ Systems ◽  
The Brain

Ageing is a natural process characterized by progressive deterioration of biological functions. Ageing causes both morphological as well as biochemical alterations in various body organs leading to deterioration of health. Proteins, enzymes and neurotransmitters are affected, which in turn can result in dysregulation of various pathways. WHO has reported that by 2020, three quarters of all deaths in developing countries will be age-associated. Currently more than 300 theories exist to explain the phenomenon of ageing; amongst them the oxidative stress theory of ageing is most studied and accepted for the molecular basis of ageing. All these processes can progress at an unprecedented pace on contact with triggering factors, leading to the development of pathological ageing. The probability of developing neurodegenerative and metabolic disorders is relatively high under such circumstances. This review emphasizes the theories and mechanisms of ageing and an overview on the aspects of age associated biochemical changes and the implications on the brain, liver and various organ systems.

scholarly journals The effect of antioxidants in Ehrlich Ascites Cancer

2021 ◽  
Vol 67 (2) ◽  
pp. 20-24
Author(s):  
Seher Yılmaz ◽  
Adem Tokpınar ◽  
Ece Eroğlu ◽  
Şükrü Ateş ◽  
Rabbia Zahid ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cancer Patients ◽  
Cell Transformation ◽  
Cancer Chemoprevention ◽  
Full Potential ◽  
Functional Screening ◽  
Molecular Oncology ◽  
Underlying Mechanisms ◽  
Antioxidant Supplement ◽  
Antioxidant Supplements

A fundamental goal in molecular oncology is to unravel the underlying mechanisms which cause the cell transformation. In line with this approach, genome-wide functional screening approaches have revealed exciting insights into heterogeneous nature of cancer. Rapidly expanding horizons of research have unraveled myriad of pathways which play instrumental role in carcinogenesis and metastasis. Oxidative stress has also been reported to be significantly involved in cancer onset and progression. In line with this approach, oxidative stress modulating chemicals have always been sharply divided into antioxidants and oxidative stress-inducing agents. Conceptual and experimental advancements have enabled us to critically analyze full potential of these two different groups of chemicals in cancer chemoprevention. Different antioxidants are currently being analyzed in different phases of clinical trials. Although it has been reported in the literature that antioxidant supplements reduce tumor cells in some tumors or cause volume reduction in solid tumor sizes, there is no definite consensus. Therefore, an antioxidant supplement guideline based on more detailed clinical research and as a result of these is needed to achieve the best care for cancer patients and to avoid risky treatments for cancer patients.

scholarly journals Type 2 Diabetes Mellitus And Vitamin C

2019 ◽  
Vol 09 (03) ◽  
pp. 232-236
Author(s):  
Shabzain Ishrat ◽  
Talea Hoor ◽  
Mohammed Sajid Abbas Jaffri
Keyword(s):  
Oxidative Stress ◽  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Vitamin C ◽  
Good Control ◽  
Type 2 Dm ◽  
Vitamin C Supplementation ◽  
Antioxidant Supplements

Type 2 diabetes mellitus (DM) is a chronic disease which deteriorates the quality of life with time. Type 2 DM accounts for more than 90% cases of diabetes mellitus as compared to other types of this disease. There is significant oxidative stress in type 2 DM which plays an important role in the pathogenesis of disease. In order to combat this oxidative stress antioxidant supplements have to be added as add on therapy along with treatment of type 2 DM. Vitamin C is the safest antioxidant which plays significant role in diminishing the oxidative stress. The vitamin C supplementation have good control of FBS and HbA1c and therefore helps in achieving better glycemic control along with prevention of lipid abnormalities.

Sign in / Sign up

Export Citation Format

Share Document