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Highly sensitive covalently functionalised integrated silicon nanowire biosensor devices for detection of cancer risk biomarker

Mohd Azmi MA, Tehrani Z, Lewis RP, Walker KA, Jones DR, Daniels DR, et al.

Biosens Bioelectron, 2014 Feb 15;52:216-24.
PMID: 24060972 DOI: 10.1016/j.bios.2013.08.030

In this article we present ultra-sensitive, silicon nanowire (SiNW)-based biosensor devices for the detection of disease biomarkers. An electrochemically induced functionalisation method has been employed to graft antibodies targeted against the prostate cancer risk biomarker 8-hydroxydeoxyguanosine (8-OHdG) to SiNW surfaces. The antibody-functionalised SiNW sensor has been used to detect binding of the 8-OHdG biomarker to the SiNW surface within seconds of exposure. Detection of 8-OHdG concentrations as low as 1 ng/ml (3.5 nM) has been demonstrated. The active device has been bonded to a disposable printed circuit which can be inserted into an electronic readout system as part of an integrated Point of Care (POC) diagnostic. The speed, sensitivity and ease of detection of biomarkers using SiNW sensors render them ideal for eventual POC diagnostics.

Matched MeSH terms: Deoxyguanosine/analogs & derivatives*; Deoxyguanosine/isolation & purification; Deoxyguanosine/metabolism
Reduction of DNA damage in older healthy adults by Tri E Tocotrienol supplementation

Chin SF, Hamid NA, Latiff AA, Zakaria Z, Mazlan M, Yusof YA, et al.

Nutrition, 2008 Jan;24(1):1-10.
PMID: 17884341

The free radical theory of aging (FRTA) suggests that free radicals are the leading cause of deteriorating physiologic function during senescence. Free radicals attack cellular structures or molecules such as DNA resulting in various modifications to the DNA structures. Accumulation of unrepaired DNA contributes to a variety of disorders associated with the aging process.

Matched MeSH terms: Deoxyguanosine/analogs & derivatives; Deoxyguanosine/urine
Curcumin attenuates oxidative damage in animals treated with a renal carcinogen, ferric nitrilotriacetate (Fe-NTA): implications for cancer prevention

Iqbal M, Okazaki Y, Okada S

Mol Cell Biochem, 2009 Apr;324(1-2):157-64.
PMID: 19165575 DOI: 10.1007/s11010-008-9994-z

Curcumin (diferuloylmethane), a biologically active ingredient derived from rhizome of the plant Curcuma longa, has potent anticancer properties as demonstrated in a plethora of human cancer cell lines/animal carcinogenesis model and also acts as a biological response modifier in various disorders. We have reported previously that dietary supplementation of curcumin suppresses renal ornithine decarboxylase (Okazaki et al. Biochim Biophys Acta 1740:357-366, 2005) and enhances activities of antioxidant and phase II metabolizing enzymes in mice (Iqbal et al. Pharmacol Toxicol 92:33-38, 2003) and also inhibits Fe-NTA-induced oxidative injury of lipids and DNA in vitro (Iqbal et al. Teratog Carcinog Mutagen 1:151-160, 2003). This study was designed to examine whether curcumin possess the potential to suppress the oxidative damage caused by kidney-specific carcinogen, Fe-NTA, in animals. In accord with previous report, at 1 h after Fe-NTA treatment (9.0 mg Fe/kg body weight intraperitoneally), a substantial increased formation of 4-hydroxy-2-nonenal (HNE)-modified protein adducts in renal proximal tubules of animals was observed. Likewise, the levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and protein reactive carbonyl, an indicator of protein oxidation, were also increased at 1 h after Fe-NTA treatment in the kidneys of animals. The prophylactic feeding of animals with 1.0% curcumin in diet for 4 weeks completely abolished the formation of (i) HNE-modified protein adducts, (ii) 8-OHdG, and (iii) protein reactive carbonyl in the kidneys of Fe-NTA-treated animals. Taken together, our results suggest that curcumin may afford substantial protection against oxidative damage caused by Fe-NTA, and these protective effects may be mediated via its antioxidant properties. These properties of curcumin strongly suggest that it could be used as a cancer chemopreventive agent.

Matched MeSH terms: Deoxyguanosine/analogs & derivatives; Deoxyguanosine/metabolism
Fulltext Training Induced Oxidative Stress-Derived DNA and Muscle Damage in Triathletes

Zainudin H, Caszo BA, Knight VF, Gnanou JV

Eurasian J Med, 2019 Jun;51(2):116-120.
PMID: 31258349 DOI: 10.5152/eurasianjmed.2019.18106

Objective: Regular moderate-intensity exercise has beneficial health effects, whereas regular strenuous exercise increases the production of oxidants that may lead to DNA, skeletal, and cardiac muscle damages. Triathletes experience strenuous muscular activity both during competition and training, being at risk of developing these tissue damages. The objective of the present study was to estimate DNA, skeletal, and cardiac muscle damages using blood biomarkers, 8-hydroxy-2'-deoxyguanosine (8-OHdG), myoglobin, and cardiac troponin I (cTnI) among young triathletes.
Materials and Methods: Age-matched seven male and seven female triathletes were recruited for the study. They were on a standardized training regimen and on average competed in at least one endurance event every month for the past 3-4 years. Serum biomarkers were measured using enzyme-linked immunosorbent assay at the start and at end of the racing season.
Results: Both male and female triathletes showed a statistically significant increase in 8-OHdG. A similar pattern of increase was seen with serum myoglobin, which was not statistically significant in both male and female triathletes. cTnI levels did not show any change in both sexes.
Conclusion: Our study shows that there could be an increased evidence of DNA damage among triathletes. However, similar effects were not observed with skeletal and cardiac muscle biomarkers.

Matched MeSH terms: Deoxyguanosine
Fulltext Antioxidant and pro-oxidant effects of oil palm (Elaeis guineensis) leaves extract in experimental diabetic nephropathy: a duration-dependent outcome

Varatharajan R, Sattar MZ, Chung I, Abdulla MA, Kassim NM, Abdullah NA

BMC Complement Altern Med, 2013;13:242.
PMID: 24074026 DOI: 10.1186/1472-6882-13-242

Catechins-rich oil palm (Elaeis guineensis) leaves extract (OPLE) is known to have antioxidant activity. Several polyphenolic compounds reported as antioxidants such as quercetin, catechins and gallic acid have been highlighted to have pro-oxidant activity at high doses. Therefore, the present study was conducted to investigate the antioxidant and pro-oxidant effects of chronically administering high dose of OPLE (1000 mg kg⁻¹) in an animal model of diabetic nephropathy (DN).

Matched MeSH terms: Deoxyguanosine/analogs & derivatives
Oxidative stress and sperm function: A systematic review on evaluation and management

Dutta S, Majzoub A, Agarwal A

Arab J Urol, 2019;17(2):87-97.
PMID: 31285919 DOI: 10.1080/2090598X.2019.1599624

Objective: To review and present the most distinct concepts on the association of reactive oxygen species (ROS) with male reproduction. Methods: The Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) guidelines were used to search PubMed, Medline, EMBASE, and the Cochrane electronic databases for studies investigating the role of oxidative stress (OS) on sperm function. Results: The literature search yielded 1857 studies, of which 1791 articles were excluded because of irrelevance of data, non-English language, non-human nature or because they were case reports or commentaries. All included studies were reviews (46), meta-analyses (one), original research studies (18) and guideline articles (one). The studies were published between 1984 and 2018. Under normal physiological conditions, ROS are vital for sperm maturation, hyperactivation, capacitation, acrosome reaction, as well as fertilisation. However, a number of endogenous and exogenous causes may induce supra-physiological levels of ROS resulting in lipid peroxidation, sperm DNA fragmentation and apoptosis, and consequently infertility. Several laboratory testing methods can be used in infertile men to diagnose OS. Treatment usually involves antioxidant supplementation and, when possible, elimination of the causative factor. Conclusion: OS is an important cause of male factor infertility. Its assessment provides essential information that can guide treatment strategies aimed at improving the male's reproductive potential. Abbreviations: bp: base-pair; CAT: catalase; LPO: lipid peroxidation; MDA: malondialdehyde; MiOXSYS: Male Infertility Oxidative System; mtDNA: mitochondrial DNA; NAD(PH): nicotinamide adenine dinucleotide (phosphate); NO: nitric oxide; 8-OHdG: 8-hydroxy-2'-deoxyguanosine; ORP: oxidation-reduction potential; OS: oxidative stress; PKA: protein kinase A; PLA2: phospholipase A2; PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses; PUFA: poly-unsaturated fatty acid; ROS: reactive oxygen species; SOD: superoxide dismutase; TAC: total antioxidant capacity; TBA: thiobarbituric acid.

Matched MeSH terms: Deoxyguanosine
Hepatoprotective mechanism of Lygodium microphyllum (Cav.) R.Br. through ultrastructural signaling prevention against carbon tetrachloride (CCl4)-mediated oxidative stress

Gnanaraj C, Shah MD, Song TT, Iqbal M

Biomed Pharmacother, 2017 Aug;92:1010-1022.
PMID: 28609838 DOI: 10.1016/j.biopha.2017.06.014

Plants have been consumed in medicinal practices for centuries. Lygodium microphyllum (Cav.) R.Br. (Lygodiaceae), also known as Old World Climbing Fern, is a medicinal plant used by local communities in Sabah for skin and dysentery ailments. This study aims to test aqueous extract of L. microphyllum leaves for hepatoprotective and immunosuppressive activity in rats. Animal studies were carried out to evaluate hepatoprotection of aqueous extract of L. microphyllum at different doses (200, 400 and 600mg/kg b.w.) against carbon tetrachloride (CCl4)-mediated liver injury and histopathological alterations. Total phenolic content in aqueous extract of L. microphyllum leaves was 206.38±9.62mg gallic acid equivalent/g. The inhibitory concentration (IC50) for free radical scavenging activity of L. microphyllum was reached at a concentration of 65μg/ml.L. microphyllum was able to prevent the increase in levels of serum alanine aminotransferase, serum aspartate aminotransferase and hepatic malondialdehyde formation in a dose-dependent manner. Immunohistochemical results evidenced the suppression of oxidative stress markers (4-hydroxynonenal, 8-hydroxydeoxyguanosine) and pro-inflammatory cytokines (Tumor Necrosis Factor-α, Interleukin-6, Prostaglandin E2). Histopathological and hepatocyte ultrastructural alterations showed protective effects by L. microphyllum against CCl4-mediated oxidative stress. Hepatoprotective mechanism of L. microphyllum can be attributed to its antioxidative effects through protection of ultrastructural organelles.

Matched MeSH terms: Deoxyguanosine/analogs & derivatives; Deoxyguanosine/metabolism