Effect of Tai Chi on Markers of Oxidative Stress: Systematic Review and Meta-Analysis.

BACKGROUND: This study aimed to synthesize the evidence of the effect of practicing Tai Chi on oxidative stress markers (OxSM). METHODS: This systematic review and meta-analysis was conducting using the MEDLINE, Cochrane Library, ScienceDirect, Scopus, Epistemonikos, Lilacs, and Ovid databases to identify randomized (RCT) and non-randomized (NRCT) clinical trials that evaluated the Tai Chi effect on OxSM compared to sedentary behavior, walking or yoga. Pooled mean differences (MDs) with 95% confidence intervals (95%CI) were estimated using the inverse variance method to determine the effect of Tai Chi on OxSM. PROSPERO register: CRD42019138362. RESULTS: Five RCT and five NRCT were included. Compared to sedentary behavior, regular Tai Chi practice increases the levels of the enzymes superoxide dismutase (MD = 34.97 U/mL, (95%CI, 9.45 to 60.48), 344 participants) and catalase (MD = 15.63 U/mL, (95%CI, 4.05 to 27.22), 110 participants), as well as reducing the levels of lipoperoxides (MD = -0.02 µmol/L, (95%CI, -0.04 to -0.00), 234 participants). For comparisons with walking or yoga, only one study per activity was identified comparing the effect on OxSM. CONCLUSIONS: Regular Tai Chi practice increases the levels of superoxide dismutase and catalase, as well as reducing the levels of lipoperoxides. More studies are necessary to determine the effect of Tai Chi on OxSM when compared to other physical activities.

Efficacy and safety of oral magnesium supplementation in reducing febrile neutropenia episodes in children with solid tumors treated with cisplatin-based chemotherapy: randomized clinical trial.

PURPOSE: Hypomagnesemia has been associated with febrile neutropenia (FN) in pediatric patients receiving cisplatin-based chemotherapy (CDDPBC). The primary aim was to determine whether oral magnesium supplementation reduces FN episodes in pediatric patients with solid tumors treated with CDDPBC. METHOD: This randomized clinical trial, with open-label, single-center, parallel group and superiority design was conducted in Hospital Infantil de Mexico Federico Gomez at Mexico City. Children ≥ 9 years with solid tumors that were to receive a CDDPBC cycle were invited to participate. Each chemotherapy cycle with CDDPBC was randomly assigned to receive oral magnesium supplementation (250 mg/day) or not receive magnesium supplementation (control group). Efficacy was determined by relative risks (RR) with 95% confidence intervals (95% CI) as well as with numbers needed to treat (NNT). Active surveillance was conducted to assess safety in both groups. Analyses were carried out by intention to treat. ClinicalTrials.gov number NCT03449693. RESULTS: One hundred and one chemotherapy cycles with CDDPBC were analyzed (50 in the magnesium supplement arm and 51 in control group). Baseline clinical characteristics were similar comparing both groups. Oral magnesium supplementation reduces FN episodes compared to control group [RR 0.53, (95% CI 0.32-0.89), NNT = 4]. In the supplemented group, patients had fewer episodes of septic shock secondary to FN [RR 0.43, (95% CI 0.02-0.94), NNT = 6] and FN appeared on average 5 days later (p = 0.031). Hypomagnesemia episodes and adverse events were similar across both groups. CONCLUSION: Oral supplementation with magnesium reduces FN episodes neutropenia in pediatric patients with solid tumors treated with CDDPBC.

Association between hot flashes severity and oxidative stress among Mexican postmenopausal women: A cross-sectional study.

OBJECTIVE: To assess the association between hot flashes (HFs) severity and oxidative stress (OS) in Mexican postmenopausal women. METHODS: A cross-sectional study was carried out with perimenopausal women aged 40-59 years community-dwelling from Mexico City, Mexico. They participated in Menopause and Oxidative Stress Project. The baseline sample consisted of 476 women recruited to participate; 161 women were excluded due to different reasons. Hence, 315 women were selected to establish two groups, a) 145 premenopausal women (yet with menstrual bleeding), and b) 170 postmenopausal women (without menses). All women were free of cardiovascular, kidney, hepatic or cancer disease, and without antioxidant supplement intake for at least six months prior to the beginning of the study; none had previously received hormone therapy. As OS markers, we measured plasma malondialdehyde using the TBARS assay, erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GPx), uric acid, and total antioxidant status; also, we calculated SOD/GPx ratio, antioxidant gap and an oxidative stress score ranging from 0 to 7. The HFs were evaluated using the Menopause Rating Scale. The women completed Spanish version of the Athens Insomnia Scale, Zung Self-Rating Anxiety Scale and Zung Self-Rating Depression Scale and a questionnaire of pro-oxidant factors. RESULTS: Stress score increased with HFs severity (mild 2.7±0.17, moderate 2.9±0.20 and severe 3.7±0.20, p = 0.001) in postmenopausal women. We observed a positive correlation between HFs severity and stress score, r = 0.247 (p = 0.001) in postmenopausal women; other test scores were not correlated. Severe HFs were a risk factor for OS (OR = 5.12, 95%CI: 1.99-13.17, p<0.05) in an adjusted multivariate analysis by different postmenopausal symptoms and pro-oxidant factors; we did not see any association in premenopausal women. CONCLUSION: Our findings suggest an association between HFs severity and OS in Mexican postmenopausal women.

Antioxidant capacity in relationship to serum lipid peroxides levels in healthy elderly of Mexico City / Capacidad antioxidante en relación a niveles séricos de lipoperóxidos en ancianos sanos de la ciudad de México

The aging is one of the factors that cause decrease in the antioxidant capacity. Likewise, it has been proposed that subjects exposed permanently to air pollution develop deficient antioxidant capacity to oxidative stress (OxS). This study aimed to analyze the antioxidant capacity against elevated lipid peroxides in healthy elderly of Mexico City. 105 adults (44 ± 10.8 years) and 126 elderly subjects were studied (68 ± 7.1 years); residents of Mexico City (clinically healthy, non-smokers, non-vitamin supplement takers) who had lived in the city for >10 years. Plasma lipoperoxides (LPO), total antioxidant status (TAS), the activity of red blood cells superoxide dismutase (SOD), and plasma glutathione peroxidase (GPx), were studied in all subjects. LPO levels were found significantly higher (p < 0.05) in the elderly subjects in comparison with the adults; in addition, TAS and GPx were higher in adults than among the elderly people (p < 0.0001). Nevertheless, SOD was similar in both groups (p = 0.346). These findings reveal that the elderly residents of Mexico City have TAS and GPx lower than adults, and similar SD activity, probably due to the fact that these antioxidants are neutralizing the higher LPO levels of elderly people. Therefore, this mechanism could be considered as an efficient antioxidant capacity in the elderly, as response to high LPO levels, since the health status, mortality prevalence and life span life of the older people of Mexico City are similar or better than other cities of Mexican Republic.

Se ha propuesto que los sujetos expuestos permanentemente a la contaminación ambiental tienen una deficiente capacidad para contrarrestar el estrés oxidativo (EOx) y que el envejecimiento es un factor causante de dicha alteración. El objetivo de este estudio fue analizar la capacidad antioxidante contra el aumento de lipoperóxidos (LPO) en adultos mayores sanos de la ciudad de México. Se estudiaron 105 adultos residentes de la ciudad de México (44 ± 10,8 años) y 126 adultos mayores (68 ± 7,1 años) clínicamente sanos, no fumadores, sin ingesta de vitaminas antioxidantes, con residencia en esta ciudad por más 10 años. Se cuantificó a todos los sujetos los LPO plasmáticos, capacidad sérica antioxidante total (AT), actividad eritrocitaria de superóxido dismutasa (SOD) y plasmática de glutatión peroxidasa (GPx). Se encontró que los niveles de LPO fueron más altos en los adultos mayores comparados con los jóvenes (p < 0,05); asimismo, AT y GPx fueron mayores en los jóvenes (p < 0,0001). La SOD fue similar en ambos grupos (p = 0,346). Estos hallazgos revelan que los ancianos residentes de la ciudad de México tienen concentraciones más bajas de AT y GPx en comparación con los adultos y una actividad similar de la SOD, debido probablemente a que estos antioxidantes están neutralizando los niveles más altos de los LPO de los ancianos. Por lo tanto, este mecanismo podría ser considerado como una capacidad antioxidante eficiente en los ancianos como respuesta a los altos niveles de LPO, ya que el estado de salud, prevalencia de mortalidad y longevidad de los adultos mayores de la ciudad de México es similar o mejor al de los residentes de otros estados de la República Mexicana.