Analysis of energy restriction and physical activity on brain function: the role of ketone body and brain-derived neurotrophic factor

Molecular Study of the Protective Effect of a Low-Carbohydrate, High-Fat Diet against Brain Insulin Resistance in an Animal Model of Metabolic Syndrome

Brain insulin resistance is linked to metabolic syndrome (MetS). A low-carbohydrate, high-fat (LCHF) diet has been proposed to have a protective effect. Therefore, this study aimed to investigate the brain insulin resistance markers in a rat animal model of MetS and the protective effects of the LCHF diet. Four groups of male rats (10/group) were created. Group I (Control) was fed a regular diet. Groups II-IV were injected with dexamethasone (DEX) to induce MetS. Group II received DEX with a regular diet. Group III (DEX + LCHF) rates were fed a low-carbohydrate, high-fat diet, while Group IV (DEX + HCLF) rats were fed a high-carbohydrate, low-fat (HCLF) diet. At the end of the four-week experiment, HOMA-IR was calculated. Moreover, cerebral gene expression analysis of S-100B, BDNF, TNF-α, IGF-1, IGF-1 R, IGFBP-2, IGFBP-5, Bax, Bcl-2, and caspase-3 was carried out. In the DEX group, rats showed a significant increase in the HOMA-IR and a decrease in the gene expression of IGF-1, IGF-1 R, IGFBP-2, IGFBP-5, BDNF, and Bcl2, with a concomitant rise in S100B, TNF-α, Bax, and caspase-3. The LCHF diet group showed a significantly opposite effect on all parameters. In conclusion, MetS is associated with dysregulated cerebral gene expression of BDNF, S100B, and TNF-α and disturbed IGF-1 signaling, with increased apoptosis and neuroinflammation. Moreover, the LCHF diet showed a protective effect, as evidenced by preservation of the investigated biochemical and molecular parameters.

Circulating fatty acids and endocannabinoidome-related mediator profiles associated to human longevity

To evaluate whether a peculiar plasma profile of fatty acids and endocannabinoidome (eCBome)-related mediators may be associated to longevity, we assessed them in octogenarians (Old; n=42) living in the east-central mountain area of Sardinia, a High-Longevity Zone (HLZ), compared to sexagenarian (Young; n=21) subjects from the same area, and to Olds (n=22) from the Northern Sardinia indicated as Lower-Longevity Zone (LLZ). We found significant increases in conjugated linoleic acid (CLA) and heptadecanoic acid (17:0) levels in Old-HLZ with respect to younger subjects and Old-LLZ subjects. Young-HLZ subjects exhibited higher circulating levels of pentadecanoic acid (15:0) and retinol. Palmitoleic acid (POA) was elevated in both Young and Old subjects from the HLZ. eCBome profile showed a significantly increased plasma level of the two endocannabinoids, N-arachidonoyl-ethanolamine (AEA) and 2-arachidonoyl-glycerol (2-AG) in Old-HLZ subjects compared to Young-HLZ and Old-LLZ respectively. In addition, we found increased N-oleoyl-ethanolamine (OEA), 2-linoleoyl-glycerol (2-LG) and 2-oleoyl-glycerol (2-OG) levels in Old-HLZ group with respect to Young-HLZ (as for OEA an d 2-LG) and both the Old-LLZ and Young-HLZ for 2-OG. The endogenous metabolite of docosahexaenoic acid (DHA), N-docosahexaenoyl-ethanolamine (DHEA) was significantly increased in Old-HLZ subjects. In conclusion, our results suggest that in the HLZ area, Young and Old subjects exhibited a favourable, albeit distinctive, fatty acids and eCBome profile that may be indicative of a metabolic pattern potentially protective from adverse chronic conditions. These factors could point to a suitable physiological metabolic pattern that may counteract the adverse stimuli leading to age-related disorders such as neurodegenerative and metabolic diseases.

Effect of nutrients and exhaustive exercise on brain function

Epidemiological evidence suggests that health-oriented eating habits are associated with maintaining optimal cognitive ability. Nutrients are functional bioactive molecules promoting human health and essential components as well. Docosahexaenoic acid (DHA; 22:6n-3), one of polyunsaturated fatty acids (PUFAs) is synthesized through elongation pathway from linolenic acid (81:3n-3) which is recognized as important source of brain function. Endurance physical exercise and energy restriction was also recognized of cardiovascular stress adjustment by enhancing brainstem cholinergic activity as well as brain function. However, we even do not know the exact neuronal mechanisms about the nutrients, β-hydroxybutyrate (β-HB) and myokine impacts on brain-derived neurotropic factor (BDNF) activation. Therefore, this review focuses on recent evidence that explains how nutrients and prolonged exercise can affect nervous system pathways that are associated with improving brain function. The results revealed that frequent consumption of polyphenols and n-3 PUFAs could modify gastrointestinal environment with beneficial microorganisms. It may suggest a new hypothesis that gastrointestinal microbiome could influence cognitive function in addition to the traditional etiological pathway. And moreover, prolonged physical exercise includes open skill sports which is induced by β-oxidation of free fatty acids stimulate BDNF. And also β-HB production which is induced by carbohydrate depletion, hypoglycemia, or fasting stimulate BDNF production that acts an significantly important roles in cognitive function and acting on brain function with brain metabolism.

Extracellular Vesicles: Delivery Vehicles of Myokines

Movement and regular physical activity are two important factors that help the human body prevent, reduce and treat different chronic diseases such as obesity, type 2 diabetes, heart diseases, hypertension, sarcopenia, cachexia and cancer. During exercise, several tissues release molecules into the blood stream, and are able to mediate beneficial effects throughout the whole body. In particular, contracting skeletal muscle cells have the capacity to communicate with other organs through the release of humoral factors that play an important role in the mechanisms of adaptation to physical exercise. These muscle-derived factors, today recognized as myokines, act as endocrine and paracrine hormones. Moreover, exercise may stimulate the release of small membranous vesicles into circulation, whose composition is influenced by the same exercise. Combining the two hypotheses, these molecules related to exercise, named exer-kines, might be secreted from muscle cells inside small vesicles (nanovesicles). These could act as messengers in tissue cross talk during physical exercise. Thanks to their ability to deliver useful molecules (such as proteins and miRNA) in both physiological and pathological conditions, extracellular vesicles can be thought of as promising candidates for potential therapeutic and diagnostic applications for several diseases.

The combined impacts of docosahexaenoic acid, endurance physical exercise, and prolonged fasting on brain function

Docosahexaenoic acid (DHA), a long chain polyunsaturated fatty acid (PUFA) is highly enriched in the membrane phospholipids of the brain, neuronal tissue and retina. Accumulating evidence suggests that brain DHA is necessary for maintaining for optimal function of the cognition and the visual system, particularly the photoreceptor, the retina. Loss of brain DHA, especially during crucial brain development period, was highly associated with visual and cognitive defects. Here it would be addressed the effect of DHA on brain functions as assessed by spatial task performance using a first generation model which is similar to human nutrition case. And also, it was well known that prolonged fasting and energy restriction with endurance physical exercise stimulate cognitive function and brain function, which is caused by upregulated ketone body and upregulated brain-derived neurotropic factor (BDNF) responses. In the DHA intake or prolonged physical exercise, upregulated BDNF can activate mitochondrial biogenesis to elevate neuronal bioenergetics and enable synaptic formation. And it also can activate DNA repair in neurons. Further study on the mechanisms about the combine effects of supplementation of DHA and energy restriction on brain function is urgently needed in this area.

Significant Acute Response of Brain-Derived Neurotrophic Factor Following a Session of Extreme Conditioning Program Is Correlated With Volume of Specific Exercise Training in Trained Men

Several studies have demonstrated an acute and chronic increase of brain-derived neurotrophic factor (BDNF) in relation to different types of physical exercise. Currently, many individuals seek physical training strategies that present different types of stimulation and volume/intensity. Thus, the extreme conditioning methodology has gained great notoriety in the scientific and non-scientific environment. Knowing that BDNF values increase in an effort-dependent manner, it is necessary to study the effects of this strategy on BDNF levels. This study aimed to evaluate the acute response of BDNF in trained men submitted to an extreme conditioning program (ECP) session. Ten volunteers underwent an acute ECP session using the “as many reps as possible” (WOD-AMRAP) method, including three types of exercise (clean, wall ball and double or single-unders) for 9 min. BDNF was measured in the plasma, being collected baseline and immediately after the session. Total load of the clean exercise was five times greater than wall ball exercise (p < 0.05; 2096.1 ± 387.4 kg vs 415.8 ± 81.03 kg), which influenced little in the total load (p < 0.05, 2511.9 ± 358.52 kg) used. For the total volume, practitioners averaged 1.7 times more repetitions in the wall ball exercise compared to clean (46.2 ± 9 vs 29.5 ± 3.8 repetitions). The volunteers averaged 75.7 ± 12.6 double-unders repetitions, bringing the total volume of training to 151.4 ± 23.7 repetitions. Regarding the BDNF values, there was a significant difference (p = 0.05) between the pre- vs post-moments (11209.85 ± 1270.4 vs 12132.96 ± 1441.93 pg/ml). Effect size for this change as moderate (ES = 0.79). We found a positive correlation between total volume of clean exercise and delta BDNF values (p = 0.049). In conclusion, a single extreme conditioning session, through the practice of the WOD-AMRAP method, is capable of increasing the acute concentrations of plasma BDNF. In practical terms, we may suggest that future studies evaluate the effect of ECP as a strategy in the treatment of disorders associated with central degenerative changes.