Caffeine prevents high-intensity exercise-induced increase in enzymatic antioxidant and Na+-K+-ATPase activities and reduction of anxiolytic like-behaviour in rats

The mitochondrial quality control system: a new target for exercise therapeutic intervention in the treatment of brain insulin resistance-induced neurodegeneration in obesity

Obesity is a major global health concern because of its strong association with metabolic and neurodegenerative diseases such as diabetes, dementia, and Alzheimer's disease. Unfortunately, brain insulin resistance in obesity is likely to lead to neuroplasticity deficits. Since the evidence shows that insulin resistance in brain regions abundant in insulin receptors significantly alters mitochondrial efficiency and function, strategies targeting the mitochondrial quality control system may be of therapeutic and practical value in obesity-induced cognitive decline. Exercise is considered as a powerful stimulant of mitochondria that improves insulin sensitivity and enhances neuroplasticity. It has great potential as a non-pharmacological intervention against the onset and progression of obesity associated neurodegeneration. Here, we integrate the current knowledge of the mechanisms of neurodegenration in obesity and focus on brain insulin resistance to explain the relationship between the impairment of neuronal plasticity and mitochondrial dysfunction. This knowledge was synthesised to explore the exercise paradigm as a feasible intervention for obese neurodegenration in terms of improving brain insulin signals and regulating the mitochondrial quality control system.

Caffeine Does Not Alter Performance, Perceptual Responses, and Oxidative Stress After Short Sprint Interval Training

Despite the abundance of research investigating the efficacy of caffeine supplementation on exercise performance, the physiological and biochemical responses to caffeine supplementation during intermittent activities are less evident. This study investigated the acute effects of caffeine supplementation on measures of exercise performance, ratings of perceived exertion, and biomarkers of oxidative stress induced by an acute bout of sprint interval training. In a randomized crossover design, 12 healthy males (age: 26 ± 4 years, height: 177.5 ± 6 cm, body mass: 80.7 ± 7.6 kg) ingested 6 mg/kg of caffeine or placebo 60 min prior to performing sprint interval training (12 × 6 s "all-out sprints" interspersed by 60 s of rest). Performance scores and ratings of perceived exertion were assessed after every sprint. Blood samples were collected before supplementation, prior to and following each sprint, and 5 and 60 min after the last sprint. Caffeine had no effect on any performance measures, ratings of perceived exertion, or biomarkers of oxidative stress (p > .05). In conclusion, caffeine supplementation does not improve performance or decrease oxidative stress after an acute bout of sprint interval training.

Adenosine triphosphate induced cell death: Mechanisms and implications in cancer biology and therapy

Adenosine triphosphate (ATP) induced cell death (AICD) is a critical cellular process that has garnered substantial scientific interest for its profound relevance to cancer biology and to therapeutic interventions. This comprehensive review unveils the intricate web of AICD mechanisms and their intricate connections with cancer biology. This review offers a comprehensive framework for comprehending the multifaceted role of AICD in the context of cancer. This is achieved by elucidating the dynamic interplay between systemic and cellular ATP homeostasis, deciphering the intricate mechanisms governing AICD, elucidating its intricate involvement in cancer signaling pathways, and scrutinizing validated key genes. Moreover, the exploration of AICD as a potential avenue for cancer treatment underscores its essential role in shaping the future landscape of cancer therapeutics.

Changes in mitochondrial biogenesis and fatty liver indicators in rat following continuous and high intensity interval training

BACKGROUND

Oxidative stress and mitochondrial dysfunction can be tracked down in most liver diseases like non-alcoholic fatty liver disease (NAFLD). The most recommended preventative method is lifestyle modification, especially exercise. The aim of this study was the investigation of changes in the indexes of mitochondrial biogenesis and fatty liver indicators in rat following continuous and high intensity interval training.

METHODS

Thirty healthy male rats were divided into three control (C=10), Continuous swimming training (CT=10) and High intensity interval swimming training groups (HIIT=10). The training groups performed their specific exercises 5 days a week for 8 weeks. 24 h after the last training session in order to prepare the serum, a blood sample was taken from the left ventricle of the rats. In addition, liver tissue was extracted and the SIRT3, PGC-1α, GSH:GSSG, MDA, LDL, HDL, LDL:HDL, TG, TC, AST, ALT and FBS variables were measured by ELISA and analysis of blood biochemistry.

RESULTS

Continuous training (CT) increased the levels of PGC-1α, SIRT3 and significantly reduced LDL, LDL:HDL, TG and FBS (P<0.05) levels. High-intensity interval training (HIIT) caused a significant increase in SIRT3 and a significant decrease in FBS (P<0.05) levels.

CONCLUSIONS

Adaptations resulting from further aerobic exercise can increase mitochondrial biogenesis factors such as PGC-1α and SIRT3 in hepatocytes, improve this process in hepatocytes, and ultimately improve the fatty liver markers. Therefore, CT may be more effective than HIIT in preventing fatty liver disease.

High intensity interval training protects from Post Traumatic Stress Disorder induced cognitive impairment

This study aimed to show the possible protective effects of high intensity interval training (HIIT) in PTSD-induced rats and probable underlying mechanisms. Female rats (n = 44) were separated as; Sedentary (SED), moderate intensity continuous training (MICT), HIIT groups. Then the groups were divided into subgroups according to PTSD induction (n = 6-8/group). Exercise groups performed HIIT or MICT for 6 weeks. On the fifth week, PTSD was induced by single prolonged stress protocol. Cognitive functions were evaluated by object recognition, anxiety levels by hole-board and elevated plus maze, and fear conditioning by passive avoidance tests. Following decapitation, malondialdehyde (MDA), glutathione (GSH), luminol and lucigenin chemiluminescence levels, and myeloperoxidase (MPO), superoxide dismutase (SOD) and catalase (CAT) activities were measured, and histopathological damage was evaluated. The data was analyzed by one-way ANOVA. Cognitive decline and aggravated anxiety levels in SED + PTSD group were improved in both PTSD-induced exercise groups (p < 0.05-0.001). The increased chemiluminescence levels, MPO activity and histological damage were depressed in both PTSD-induced exercise groups (p < 0.05-0.001). The risen MDA levels in SED + PTSD group were suppressed only in HIIT + PTSD group (p < 0.01-0.001). The decreased GSH levels were increased by MICT (p < 0.05-0.001), and CAT and SOD activities were improved via HIIT (p < 0.05). Compared to SED group, latency was decreased in SED + PTSD (p < 0.05-0.01) group. Neuronal damage scores were alleviated in both PTSD-induced exercise groups (p < 0.001). PTSD-induced memory decline was protected by both of the exercise models however more effectively by HIIT via decreasing oxidative stress, anxiety levels and by improving antioxidant capacity as a protective system for neuronal damage.

Effects of Dietary Supplements on Adaptations to Endurance Training

Endurance training leads to a variety of adaptations at the cellular and systemic levels that serve to minimise disruptions in whole-body homeostasis caused by exercise. These adaptations are differentially affected by training volume, training intensity, and training status, as well as by nutritional choices that can enhance or impair the response to training. A variety of supplements have been studied in the context of acute performance enhancement, but the effects of continued supplementation concurrent to endurance training programs are less well characterised. For example, supplements such as sodium bicarbonate and beta-alanine can improve endurance performance and possibly training adaptations during endurance training by affecting buffering capacity and/or allowing an increased training intensity, while antioxidants such as vitamin C and vitamin E may impair training adaptations by blunting cellular signalling but appear to have little effect on performance outcomes. Additionally, limited data suggest the potential for dietary nitrate (in the form of beetroot juice), creatine, and possibly caffeine, to further enhance endurance training adaptation. Therefore, the objective of this review is to examine the impact of dietary supplements on metabolic and physiological adaptations to endurance training.

A caffeine-supplemented diet modulates oxidative stress markers and prevents oxidative damage in the livers of Nile tilapia (Oreochromis niloticus) exposed to hypoxia

Recent evidence has revealed the involvement of oxidative stress and oxidative damage with health impairment and mortality in fish exposed to hypoxia. Thus, natural compounds with antioxidant and free-radical-scavenging properties, such as caffeine, might help to prevent or reduce hepatic damage elicited by hypoxia. Thus, the aim of this study was to evaluate whether dietary supplementation with caffeine could prevent or reduce oxidative damage in the livers of Nile tilapia (Oreochromis niloticus) exposed to hypoxia. Hepatic reactive oxygen species, lipid peroxidation levels, and xanthine oxidase (XO) activity were higher in fish exposed to hypoxia compared with normoxia. Hepatic catalase, glutathione peroxidase, and glutathione S-transferase activities, as well as the antioxidant capacity against peroxyl radical levels, were lower in fish exposed to hypoxia compared with normoxia. No significant difference between groups was observed regarding hepatic superoxide dismutase activity. Dietary supplementation with 8% caffeine prevented all alterations elicited by hypoxia. Based on this evidence, the use of dietary supplementation with 8% caffeine can be an interesting approach to preventing hepatic lipid damage and impairment of the antioxidant defense system elicited by hypoxia, and this effect can be mediated by protective effects on XO activity.

Coffee, caffeine, chlorogenic acid, and the purinergic system

Coffee is a drink prepared from roasted coffee beans and is lauded for its aroma and flavour. It is the third most popular beverage in the world. This beverage is known by its stimulant effect associated with the presence of methylxanthines. Caffeine, a purine-like molecule (1,3,7 trymetylxantine), is the most important bioactive compound in coffee, among others such as chlorogenic acid (CGA), diterpenes, and trigonelline. CGA is a phenolic acid with biological properties as antioxidant, anti-inflammatory, neuroprotector, hypolipidemic, and hypoglicemic. Purinergic system plays a key role inneuromodulation and homeostasis. Extracellular ATP, other nucleotides and adenosine are signalling molecules that act through their specific receptors, namely purinoceptors, P1 for nucleosides and P2 for nucleotides. They regulate many pathological processes, since adenosine, for instance, can limit the damage caused by ATP in the excitotoxicity from the neuronal cells. The primary purpose of this review is to discuss the effects of coffee, caffeine, and CGA on the purinergic system. This review focuses on the relationship/interplay between coffee, caffeine, CGA, and adenosine, and their effects on ectonucleotidases activities as well as on the modulation of P1 and P2 receptors from central nervous system and also in peripheral tissue.