A novel biomarker explaining the role of oxidative stress in exercise and l-tyrosine supplementation: thiol/disulphide homeostasis

The Use of Probiotics Combined with Exercise Affects Thiol/Disulfide Homeostasis, an Oxidative Stress Parameter

Background: Intestinal microbiota play a role in the health and performance of athletes, and can be influenced by probiotics. Thus, in this study, we aimed to investigate the effect of the use of probiotics combined with chronic exercise on the thiol/disulfide homeostasis, a novel marker of oxidative stress. Methods: Male Wistar rats were randomly divided into four groups: control (Cn), exercise (Ex), probiotics (P), and probiotics + exercise (PEx). A capsule containing 6 × 10⁸ CFU of L. rhamnosus, L. paracasei, L. acidophilus, and B. lactis was given daily for eight weeks to all the experimental animals. The total thiol (TT, μmol/L) and native thiol (NT, μmol/L) concentrations were measured to determine the oxidative stress parameters. The dynamic disulfide (DD, %), reduced thiol (RT, %), oxidized thiol (OT, %), and thiol oxidation reduction (TOR, %) ratios were analyzed. Results: The TT level was found to be significantly higher in the Ex group (p = 0.047, η² = 0.259). The DD level, a marker of oxidation, was significantly lower in the PEx group (p = 0.042, η² = 0.266); the highest value of this parameter was found in the Ex group. The use of probiotics alone had no effect on thiol/disulfide homeostasis. Conclusions: We showed, for the first time, that probiotics administered “with exercise” decreased dynamic disulfide and significantly reduced oxidative damage. Therefore, we speculate that the use of probiotics in sports involving intense exercise might be beneficial to reduce oxidative stress.

Association of nanoparticle exposure with serum metabolic disorders of healthy adults in printing centers

Printers are everyday devices in both our homes and workplaces. We have previously found high occupational exposure levels to toner-based printer emitted nanoparticles (PEPs) at printing centers. To elucidate the potential health effects from exposure to PEPs, a total of 124 human serum samples were collected from 32 workers in the printing centers during the repeated follow-up measurements, and global serum metabolomics were analyzed in three ways: correlation between metabolic response and personal exposure (dose response exposure); metabolite response changes between Monday and Friday of a work week (short-term exposure), and metabolite response in relation to length of service in a center (long-term exposure). A total of 52 key metabolites changed significantly in relation to nanoparticle exposure levels. The primary dysregulated pathways included inflammation and immunity related arginine and tryptophan metabolism. Besides, some distinct metabolite expression patterns were found to occur during the transition from short-term to long-term exposures, suggesting cumulative effect of PEPs exposure. These findings, for the first time, highlight the inhalation exposure responses to printer emitted nanoparticles at the metabolite level, potentially serving as pre-requisites for whole organism and population responses, and are inline with emerging findings on potential health effects.

Oxidative stress response to different exercise intensity with an automated assay: thiol/disulphide homeostasis

The aim of this study was to investigate the effect of different intensity treadmill exercises on the thiol disulphide homeostasis which is a new marker of oxidative stress in rats. Male albino Wistar rats were randomly divided into four groups as follows: control (CNT), low (LEx), moderate (MEx) and high-intensity exercise (HEx) group. Exercise was performed for 4 weeks. Following completion of the experimental protocol, serum total thiol, native thiol and disulphide concentrations were determined using a novel automated measurement method. Additionally, dynamic disulphide status, reduced thiol, oxidised thiol and thiol oxidation reduction percentage ratios were compared among the groups. Disulphide levels were significantly lower in MEx group and highest in CNT group (p = .047). The lowest oxidised thiol and the highest reduced thiol were determined in CNT group (p = .086; p = .083). These findings indicate that moderate-intensity exercise is more effective in reducing oxidative stress than low and high-intensity exercise.

Analysis of thiol/disulphide homeostasis and oxidant-antioxidant status as a result of exposure to radio-frequency electromagnetic fields

The aim of the current study is to investigate the effect of daily long-term radio-frequency electromagnetic field (RF-EMFs) exposure on thiol/disulphide homeostasis and oxidant-antioxidant status in the serum of rats. Fourteen male Sprague Dawley rats were divided into two equal groups (n = 7). They were grouped as group 1 (sham-control) and group 2 (2100 MHz exposed). Group 2 rats were exposed to GSM-like signals for 5 h/day, 7 days per week for 14 days. In serum of blood samples, the native, total and native/total thiol levels and antioxidant-oxidant parameters were analyzed. The study revealed that the mean serum total thiol levels of GSM exposure group was rather higher than sham-control group (p = 0,219); the mean serum native thiol levels of GSM exposure group was rather higher than sham-control group (p = 0,416), and the mean serum disulphide levels of GSM exposure group was rather higher than sham-control group (p = 0,566). On the other hand, the mean serum total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) of GSM exposure group were higher than sham-control group. There are no data in the literature, that examine the effects of RF-EMFs on thiol/disulphide homeostasis. The results of this study, indicate that RF-EMFs did not cause oxidative stress and statistically changes in thiol/disulphide homeostasis. More sample sizes and longer-term exposures are needed to confirm the results of this study.

The effects of 5-hydroxytryptophan on carrageenan-induced mouse paw oedemas

ABSTRACT Objective 5-Hydroxytryptophan is the precursor compound of serotonin biosynthesis. The oral absorption of 5-Hydroxytryptophan is close to 100% and, unlike serotonin, it crosses the blood-brain barrier freely. 5-Hydroxytryptophan has been used as a food supplement for many years to treat anxiety and depression. Recent studies have shown that 5-Hydroxytryptophan suppresses the pro-inflammatory mediators and is effective in some inflammatory diseases, such as arthritis and allergic asthma. However, the role of 5-Hydroxytryptophan supplements on acute peripheral inflammation has not been investigated yet. In this study, the in vivo anti-inflammatory activity of 5-Hydroxytryptophan was evaluated with a carrageenan-induced paw oedema test in mice. Methods For the investigation of the acute antiinflammatory activity, single oral doses of 5-Hydroxytryptophan (1.5, 5 and 20mg/kg) were given to mice 1.5 hours prior to the carrageenan test. For chronic activity, the same oral doses were administered daily for two weeks prior to the carrageenan test on the 14th day. To induce inflammation, 0.01mL of 2% carrageenan was injected into the paws of mice. Results Supplementation with 5-Hydroxytryptophan significantly reduced inflammation in a dose-independent manner which was irrespective of the duration of exposure (per cent inhibition in acute experiments was 35.4%, 20.9%, 24.0%, and per cent inhibition in chronic experiments was 29.5%, 35.3%, 40.8% for the doses of 1.5, 5, and 20mg/kg, respectively). Conclusion Our findings demonstrate for the first time that 5-HTP supplements have the potential of suppressing the measures of acute peripheral inflammation. It is suggested that, apart from several diseases where serotonin is believed to play an important role, including depression, patients with inflammatory conditions may also benefit from 5-HTP.