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We investigated the effects of melatonin on the onset and resolution of the oxidative stress in the cardiac muscle in melatonin-treated and nontreated rats subjected to an exhaustive exercise session. Forty male rats were divided into: melatonin-treated (20 mg/kg supplemented for 10 d) and control. On the 10th day, each group was subdivided according to euthanasia moments: control or melatonin-treated not exercised (C0h and M0h); immediately after the exercise (CIA and MIA); and 2 h after exercise (C2h and M2h). The heart of animals was removed and the levels of oxidative stress index (OSI) and the formation of thiobarbituric acid reactive substances (TBARS), protein carbonyl, and the activities of aconitase, catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) were evaluated. Total antioxidant status (TAS), total oxidant status (TOS), and the protein expression of CAT, GPx, and SOD was also measured. Our data revealed significant differences on: (i) OSI (p=.029), CAT activity (p=.016), CAT content (p<.001), GPx content (p=.014), reduced glutathione levels (p<.001), and aconitase activity (p<.001) for interaction of melatonin; (ii) GPx activity (p=.005), reduced glutathione (p=.004), protein carbonyl (p=.035), and TBARS levels (p=.028) between groups, and (iii) TBARS levels (p=.016) for significance between moments. Although the exhaustive exercise protocol imposed mild oxidative stress on the cardiac tissue of rats, melatonin induced antioxidant responses that rebalanced the redox status of the cardiac tissue, especially after exhaustive exercise. [ABSTRACT FROM AUTHOR]

This review outlines the various factors associated with unhealthy aging which includes becoming frail and dependent. With many people not engaging in recommended exercise, facilitators and barriers to engage with exercise must be investigated to promote exercise uptake and adherence over the lifespan for different demographics, including the old, less affluent, women, and those with different cultural-ethnic backgrounds. Governmental and locally funded public health messages and environmental facilitation (gyms, parks etc.) can play an important role. Studies have shown that exercise can act as a conductor to balance oxidative stress, immune and endocrine functions together to promote healthy aging and reduce the risk for age-related morbidities, such as cardiovascular disease and atherosclerosis, and promote cognition and mood over the lifespan. Like a classic symphony orchestra, consisting of four groups of related musical instruments – the woodwinds, brass, percussion, and strings – the aging process should also perform in harmony, with compassion, avoiding the aggrandizement of any of its individual parts during the presentation. This review discusses the wide variety of molecular, cellular and endocrine mechanisms (focusing on the steroid balance) underlying this process and their interrelationships. [ABSTRACT FROM AUTHOR]

Abstract: Methanolic extract powders of acerola, passion fruit and pineapple industrial residues, including pulp, seeds and peel, altogether (except for acerola) devoid of seeds, were screened for antioxidant capacity. The total phenolic contents (TPCs) of the extract powders were compared with their radical-scavenging activities (RSA) against both and superoxide anion () radicals, and their protective effect against liposome peroxidation, triggered by peroxyl radical. Lipid peroxidation was followed by the fluorescence decay of the probe, 4,4-difluoro-5-(4-phenyl-1,3-butadienyl)-4-bora-3a,4a-diaza-s-indacene-3-undecanoic acid (C11-BODIPY581/591). The TPCs of acerola, passion fruit and pineapple extract powders were (94.6 ± 7.4); (41.2±4.2) and (9.1±1.3) mg of gallic acid equivalents g−1 of dry extract, respectively. Acerola showed the best RSA- scores, whereas passion fruit was more protective on the RSA- system. Together with the protective effects against lipid peroxidation (rate of BODIPY decay), which were similar for acerola and passion fruit extracts, these data suggest that the methanolic extracts of acerola and passion fruit residues may be useful as antioxidant supplements, particularly the acerola extract, due to its high phenolic content. [Copyright &y& Elsevier]

The aim of the present transversal study was to evaluate the clinical and biochemical salivary parameters of children with and without erosive tooth wear (ETW). The study population was children aged 4 to 9 years. A trained and calibrated examiner (kappa value for intraexaminer reliability = 0.89) classified the children into ETW (n = 24) and control groups (n = 24), and applied the O'Brien index. The salivary flow rate was initially evaluated by stimulated sialometry (paraffin chewing). Afterwards, the collected saliva was submitted to biochemical analyses of pH, uric acid, total buffering capacity, ferric-reducing antioxidant power, reduced glutathione, calcium, and phosphorus. Among the ETW children, 20 (83%) had dental lesions restricted to enamel, and 4 (17%) presented lesions affecting both enamel and dentin. A statistically significant difference between the groups was obtained only for the pH values (t-test; p = 0.004), with averages of 7.31 and 7.56 for the control and the ETW groups, respectively. Considering the parameters evaluated in general, it is suggested that the salivary profile of children with ETW does not differ considerably from that of children without ETW. However, the pH mean value seems to be slightly higher in ETW children, but is still within the normal physiological range.

Neurosporaxanthin (NX) is a carboxylic carotenoid produced by some filamentous fungi, including species of the genera Neurospora and Fusarium . NX biosynthetic genes and their regulation have been thoroughly investigated in Fusarium fujikuroi , an industrial fungus used for gibberellin production. In this species, carotenoid-overproducing mutants, affected in the regulatory gene carS , exhibit an upregulated expression of the NX pathway. Based on former data on a stimulatory effect of nitrogen starvation on carotenoid biosynthesis, we developed culture conditions with carS mutants allowing the production of deep-pigmented mycelia. With this method, we obtained samples with ca. 8 mg NX/g dry mass, in turn the highest concentration for this carotenoid described so far. NX-rich extracts obtained from these samples were used in parallel with carS -complemented NX-poor extracts obtained under the same conditions, to check the antioxidant properties of this carotenoid in in vitro assays. NX-rich extracts exhibited higher antioxidant capacity than NX-poor extracts, either when considering their quenching activity against [O 2 ( 1  g )] in organic solvent (singlet oxygen absorption capacity (SOAC) assays) or their scavenging activity against different free radicals in aqueous solution and in liposomes. These results make NX a promising carotenoid as a possible feed or food additive, and encourage further studies on its chemical properties., Competing Interests: The authors declare no conflict of interest.