The lighter side of BDNF

The BDNF Val66Met polymorphism and health-related quality of life in youth with obesity

The brain derived-neurotrophic factor (BDNF) Val66Met polymorphism causes functional changes in BDNF, and is associated with obesity and some psychiatric disorders, but its relationship to health-related quality of life (HRQoL) remains unknown. This study examined, in youth with obesity, whether carriers of the BDNF Val66met polymorphism Met-alleles (A/A or G/A) differed from noncarriers (G/G) on HRQoL. The participants were 187 adolescents with obesity. Ninety-nine youth were carriers of the homozygous Val/Val (G/G) alleles, and 88 were carriers of the Val/Met (G/A) or Met/Met (A/A) alleles. Blood samples were drawn in the morning after an overnight fast for genotyping. HRQoL was measured using the Pediatric-Quality of Life core version. Compared to carriers of the Val66Met Val (G/G) alleles, carriers of the Met-Alleles reported significantly higher physical -HRQoL (p = 0.02), school-related HRQoL, (p = 0.05), social-related HRQoL (p = 0.05), and total HRQoL (p = 0.03), and a trend for Psychosocial-HRQoL. Research is needed to confirm our findings and determine whether carriers of the BDNF Val66Met homozygous Val (G/G) alleles may be at risk of diminished HRQoL, information that can influence interventions in a high-risk population of inactive youth with obesity.

Use of Complementary and Integrative Medicine for Alzheimer's Disease and Cognitive Decline

Integrative medicine takes a holistic approach because it considers multiple aspects of the individual. This includes a person's physical, emotional, interpersonal, behavioral, nutritional, environmental, and spiritual dimensions of wellbeing that contribute to the Whole Person Health. There is increasing interest and popularity of integrative approaches to treating cognitive decline and dementia because of the multifactorial nature of aging and the limited pharmacological interventions available in treating cognitive decline and dementia, particularly Alzheimer's disease, the most common type of dementia. This review summarizes the existing evidence using complementary and integrative medicine therapies in cognitive decline and Alzheimer's disease. This includes the use of mind-body therapies, lifestyle interventions (nutritional, physical exercise, stress reduction), and other integrative modalities. Unfortunately, there are still limited studies available to guide clinicians despite the increasing popularity of integrative treatments.

Targeting BDNF with acupuncture: A novel integrated strategy for diabetes and depression comorbidity

Diabetes and depression are common comorbid conditions that impose a substantial health burden. Acupuncture may effectively improve symptoms in patients with diabetes and depression, but the underlying mechanism remains unclear. Brain-derived neurotrophic factor (BDNF) may play a vital role in the effects of acupuncture on diabetes and depression comorbidity. This review summarizes the potential role of BDNF in acupuncture for diabetes and depression comorbidity. BDNF appears to exert its effects via the BDNF-TrkB-ERK-CREB signaling pathway. BDNF levels are reduced in diabetes and depression, and acupuncture may increase BDNF expression, improving symptoms and glycemic control. High-quality research is needed to validate the efficacy of acupuncture for diabetes and depression comorbidity. Randomized controlled trials and mechanistic studies should investigate the BDNF pathway and other potential mechanisms. Improved understanding of the links between diabetes, depression and acupuncture may enable targeted and individualized patient care. Earlier diagnosis and management of diabetes and depression comorbidity should also be a priority.

Understanding the Gut-Brain Axis and Its Therapeutic Implications for Neurodegenerative Disorders

The gut-brain axis (GBA) is a complex bidirectional communication network connecting the gut and brain. It involves neural, immune, and endocrine communication pathways between the gastrointestinal (GI) tract and the central nervous system (CNS). Perturbations of the GBA have been reported in many neurodegenerative disorders (NDDs), such as Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS), among others, suggesting a possible role in disease pathogenesis. The gut microbiota is a pivotal component of the GBA, and alterations in its composition, known as gut dysbiosis, have been associated with GBA dysfunction and neurodegeneration. The gut microbiota might influence the homeostasis of the CNS by modulating the immune system and, more directly, regulating the production of molecules and metabolites that influence the nervous and endocrine systems, making it a potential therapeutic target. Preclinical trials manipulating microbial composition through dietary intervention, probiotic and prebiotic supplementation, and fecal microbial transplantation (FMT) have provided promising outcomes. However, its clear mechanism is not well understood, and the results are not always consistent. Here, we provide an overview of the major components and communication pathways of the GBA, as well as therapeutic approaches targeting the GBA to ameliorate NDDs.

Signal processing in the vagus nerve: Hypotheses based on new genetic and anatomical evidence

Each organism must regulate its internal state in a metabolically efficient way as it interacts in space and time with an ever-changing and only partly predictable world. Success in this endeavor is largely determined by the ongoing communication between brain and body, and the vagus nerve is a crucial structure in that dialogue. In this review, we introduce the novel hypothesis that the afferent vagus nerve is engaged in signal processing rather than just signal relay. New genetic and structural evidence of vagal afferent fiber anatomy motivates two hypotheses: (1) that sensory signals informing on the physiological state of the body compute both spatial and temporal viscerosensory features as they ascend the vagus nerve, following patterns found in other sensory architectures, such as the visual and olfactory systems; and (2) that ascending and descending signals modulate one another, calling into question the strict segregation of sensory and motor signals, respectively. Finally, we discuss several implications of our two hypotheses for understanding the role of viscerosensory signal processing in predictive energy regulation (i.e., allostasis) as well as the role of metabolic signals in memory and in disorders of prediction (e.g., mood disorders).

Signalling cognition: the gut microbiota and hypothalamic-pituitary-adrenal axis

Cognitive function in humans depends on the complex and interplay between multiple body systems, including the hypothalamic-pituitary-adrenal (HPA) axis. The gut microbiota, which vastly outnumbers human cells and has a genetic potential that exceeds that of the human genome, plays a crucial role in this interplay. The microbiota-gut-brain (MGB) axis is a bidirectional signalling pathway that operates through neural, endocrine, immune, and metabolic pathways. One of the major neuroendocrine systems responding to stress is the HPA axis which produces glucocorticoids such as cortisol in humans and corticosterone in rodents. Appropriate concentrations of cortisol are essential for normal neurodevelopment and function, as well as cognitive processes such as learning and memory, and studies have shown that microbes modulate the HPA axis throughout life. Stress can significantly impact the MGB axis via the HPA axis and other pathways. Animal research has advanced our understanding of these mechanisms and pathways, leading to a paradigm shift in conceptual thinking about the influence of the microbiota on human health and disease. Preclinical and human trials are currently underway to determine how these animal models translate to humans. In this review article, we summarize the current knowledge of the relationship between the gut microbiota, HPA axis, and cognition, and provide an overview of the main findings and conclusions in this broad field.

Toward a Bio-Organon: A model of interdependence between energy, information and knowledge in living systems

What is an organism? In the absence of a fundamental biological definition, what constitutes a living organism, whether it is a unicellular microbe, a multicellular being or a multi-organismal society, remains an open question. New models of living systems are needed to address the scale of this question, with implications for the relationship between humanity and planetary ecology. Here we develop a generic model of an organism that can be applied across multiple scales and through major evolutionary transitions to form a toolkit, or bio-organon, for theoretical studies of planetary-wide physiology. The tool identifies the following core organismic principles that cut across spatial scale: (1) evolvability through self-knowledge, (2) entanglement between energy and information, and (3) extrasomatic "technology" to scaffold increases in spatial scale. Living systems are generally defined by their ability to self-sustain against entropic forces of degradation. Life "knows" how to survive from the inside, not from its genetic code alone, but by utilizing this code through dynamically embodied and functionally specialized flows of information and energy. That is, entangled metabolic and communication networks bring encoded knowledge to life in order to sustain life. However, knowledge is itself evolved and is evolving. The functional coupling between knowledge, energy and information has ancient origins, enabling the original, cellular "biotechnology," and cumulative evolutionary creativity in biochemical products and forms. Cellular biotechnology also enabled the nesting of specialized cells into multicellular organisms. This nested organismal hierarchy can be extended further, suggesting that an organism of organisms, or a human "superorganism," is not only possible, but in keeping with evolutionary trends.

Combination of Shengmai San and Radix puerariae ameliorates depression-like symptoms in diabetic rats at the nexus of PI3K/BDNF/SYN protein expression

BACKGROUND

Hyperglycemia is a characteristic feature of diabetes that often results in neuropsychological complications such as depression. Diabetic individuals are more vulnerable to experience depression compared to the normal population. Thus, novel treatment approaches are required to reduce depressive symptoms among diabetic individuals. Traditional Chinese medicines (TCMs) such as Shengmai San (SMS) and Radix puerariae (R) are usually widely used to treat ailments such as neurological complications since ancient time.

METHODS

In this study, SMS was combined with R to prepare an R-SMS formulation and screened for their antidepressant activity in diabetic rats. The antidepressant potential of the prepared combination was evaluated behaviorally using open field test, novelty-induced hypophagia, and forced swim test in diabetic rats with biochemical and protein expression (PI3K, BDNF [brain-derived neurotrophic factor], and SYN [presynaptic vesicle protein]) analysis.

RESULTS

Diabetic rats (streptozotocin, 45 mg/kg) showed elevated fasting blood glucose (FBG) >12 mM with depressive symptoms throughout the study. Treatment with R-SMS (0.5, 1.5, and 4.5 g/kg) significantly reverted depressive symptoms in diabetic rats as evinced by significantly (p < 0.05) reduced immobility time with an increased tendency to eat food in a novel environment. Treatment with R-SMS also significantly increased the protein expression of PI3K, BDNF, and SYN protein, which play a crucial role in depression.

CONCLUSION

This study showed that R-SMS formulation antagonized depressive symptoms in diabetic rats; thus, this formulation might be studied further to develop as an antidepressant.

Regulation of Satiety by Bdnf-e2-Expressing Neurons through TrkB Activation in Ventromedial Hypothalamus

The transcripts for Bdnf (brain-derived neurotrophic factor), driven by different promoters, are expressed in different brain regions to control different body functions. Specific promoter(s) that regulates energy balance remain unclear. We show that disruption of Bdnf promoters I and II but not IV and VI in mice (Bdnf-e1^-/-, Bdnf-e2^-/-) results in obesity. Whereas Bdnf-e1^-/- exhibited impaired thermogenesis, Bdnf-e2^-/- showed hyperphagia and reduced satiety before the onset of obesity. The Bdnf-e2 transcripts were primarily expressed in ventromedial hypothalamus (VMH), a nucleus known to regulate satiety. Re-expressing Bdnf-e2 transcript in VMH or chemogenetic activation of VMH neurons rescued the hyperphagia and obesity of Bdnf-e2^-/- mice. Deletion of BDNF receptor TrkB in VMH neurons in wildtype mice resulted in hyperphagia and obesity, and infusion of TrkB agonistic antibody into VMH of Bdnf-e2^-/- mice alleviated these phenotypes. Thus, Bdnf-e2-transcripts in VMH neurons play a key role in regulating energy intake and satiety through TrkB pathway.

Interplay of skeletal muscle and adipose tissue: sarcopenic obesity

Sarcopenic obesity is becoming a global health concern, owing to the rising older population, causing cardiometabolic morbidity and mortality. Loss of muscle exceeding normal age-related changes has been revealed to be associated with obesity, aggravating each other through complex interactions. Physiological regeneration and proliferation of muscle tissue are achieved through harmonious processes of regulated inflammation, autophagy, muscle satellite cell proliferation, and signaling molecule function. Adipokines and myokines are signaling molecules from adipose tissue and muscle, respectively, that exert autocrine, paracrine, and endocrine effects on fat and muscle tissues. These signaling molecules interact with each other to regulate metabolic homeostasis. However, excessive adiposity creates pro-inflammatory conditions, leading to metabolic disorders and the disorganization of systemic homeostasis. Therefore, obesity impedes muscle tissue regeneration and induces the loss of muscle mass and function. Numerous studies have attempted to demonstrate the pathophysiological interaction between sarcopenia and obesity, but the interwoven matrix of the relationship between myokines and adipokines has made it difficult for researchers to understand them. This review briefly describes updated information about the crosstalk between muscle and adipose tissue.

The Role of BDNF as a Biomarker in Cognitive and Sensory Neurodegeneration

Brain-derived neurotrophic factor (BDNF) has a crucial function in the central nervous system and in sensory structures including olfactory and auditory systems. Many studies have highlighted the protective effects of BDNF in the brain, showing how it can promote neuronal growth and survival and modulate synaptic plasticity. On the other hand, conflicting data about BDNF expression and functions in the cochlear and in olfactory structures have been reported. Several clinical and experimental research studies showed alterations in BDNF levels in neurodegenerative diseases affecting the central and peripheral nervous system, suggesting that BDNF can be a promising biomarker in most neurodegenerative conditions, including Alzheimer's disease, shearing loss, or olfactory impairment. Here, we summarize current research concerning BDNF functions in brain and in sensory domains (olfaction and hearing), focusing on the effects of the BDNF/TrkB signalling pathway activation in both physiological and pathological conditions. Finally, we review significant studies highlighting the possibility to target BDNF as a biomarker in early diagnosis of sensory and cognitive neurodegeneration, opening new opportunities to develop effective therapeutic strategies aimed to counteract neurodegeneration.

The influence of the BDNF Val66Met genotype on emotional recognition memory in post-traumatic stress disorder

Dysregulated consolidation of emotional memories is a core feature of posttraumatic stress disorder (PTSD). Brain Derived Neurotrophic Factor (BDNF) influences synaptic plasticity and emotional memory consolidation. The BDNF Val66Met polymorphism has been associated with PTSD risk and memory deficits respectively, although findings have been inconsistent, potentially due to a failure to control for important confounds such as sex, ethnicity, and the timing/extent of previous trauma experiences. Furthermore, very little research has examined the impact of BDNF genotypes on emotional memory in PTSD populations. This study investigated the interaction effects of Val66Met and PTSD symptomatology in an emotional recognition memory task in 234 participants divided into healthy control (n = 85), trauma exposed (TE: n = 105) and PTSD (n = 44) groups. Key findings revealed impaired negative recognition memory in PTSD compared to control and TE groups and in participants with the Val/Met compared to the Val/Val genotype. There was a group × genotype interaction showing no Met effect in the TE group despite significant effects in PTSD and controls. Results suggest that people previously exposed to trauma who do not develop PTSD may be protected from the BDNF Met effect, however more research is needed to replicate findings and to explore the epigenetic and neural processes involved.

Novel ketamine and zinc treatment for anorexia nervosa and the potential beneficial interactions with the gut microbiome

Anorexia nervosa (AN) is a severe illness with diverse aetiological and maintaining contributors including neurobiological, metabolic, psychological, and social determining factors. In addition to nutritional recovery, multiple psychological and pharmacological therapies and brain-based stimulations have been explored; however, existing treatments have limited efficacy. This paper outlines a neurobiological model of glutamatergic and γ-aminobutyric acid (GABA)-ergic dysfunction, exacerbated by chronic gut microbiome dysbiosis and zinc depletion at a brain and gut level. The gut microbiome is established early in development, and early exposure to stress and adversity contribute to gut microbial disturbance in AN, early dysregulation to glutamatergic and GABAergic networks, interoceptive impairment, and inhibited caloric harvest from food (e.g., zinc malabsorption, competition for zinc ions between gut bacteria and host). Zinc is a key part of glutamatergic and GABAergic networks, and also affects leptin and gut microbial function; systems dysregulated in AN. Low doses of ketamine in conjunction with zinc, could provide an efficacious combination to act on NMDA receptors and normalise glutamatergic, GABAergic and gut function in AN.

Continuous exposure to alpha-glycosyl isoquercitrin from mid-gestation ameliorates polyinosinic-polycytidylic acid-disrupted hippocampal neurogenesis in rats

Polyinosinic-polycytidylic acid (PIC) provides a model of developmental neuropathy by inducing maternal immune activation. We investigated the effects of an antioxidant, alpha-glycosyl isoquercitrin (AGIQ), on PIC-induced developmental neuropathy in rats, focusing on postnatal hippocampal neurogenesis. On gestational day 15, PIC at 4 mg/kg body weight was administered to dams intravenously. AGIQ either at 0.25% or 0.5% was administered through the diet to dams from gestational day 10 until weaning on day 21 post-delivery and, thereafter, to offspring until postnatal day 77 (adult stage). At weaning, the numbers of TBR2⁺ cells and PCNA⁺ cells in the subgranular zone and reelin⁺ cells in the dentate gyrus hilus in offspring of dams treated with PIC only were decreased compared with untreated controls. In contrast, 0.5% AGIQ ameliorated these changes and increased the transcript levels of genes related to signaling of reelin (Reln and Vldlr), growth factors (Bdnf, Cntf, Igf1, and Igf1r), and Wnt/β-catenin (Wnt5a, Lrp6, Fzd1, and Fzd3). In adults, AGIQ increased the number of FOS⁺ granule cells at 0.25% and the transcript levels of NMDA-type glutamate receptor genes, Grin2a and Grin2b, at 0.25% and 0.5%, respectively. These results suggest that mid-gestation PIC treatment decreased the abundance of type-2b neural progenitor cells (NPCs) by reducing NPC proliferation in relation with suppression of reelin signaling at weaning. We suggest that AGIQ ameliorated the PIC-induced suppressed neurogenesis by enhancing reelin, growth factor, and Wnt/β-catenin signaling at weaning to rescue NPC proliferation and increased synaptic plasticity by enhancing glutamatergic signaling via NMDA-type receptors after maturation.

Brain-derived neurotrophic factor associated with kidney function

BACKGROUND

We examined the relationship between brain-derived neurotrophic factor (BDNF) and chronic kidney disease (CKD).

METHODS

First, a cross-sectional study was conducted in 480 participants without known diabetes. An oral glucose tolerance test (OGTT) was administered after overnight fasting, and blood samples were collected at 0, 30, and 120 min. Second, a total of 3003 participants were enrolled for the case-control genetic analysis. After assigning them to a case or a control group based on age and CKD status, we investigated the association between BDNF gene variants and susceptibility to CKD.

RESULTS

A higher fasting serum BDNF quartile was significantly associated with a lower prevalence of CKD (P value for trend  < 0.001). Based on the receiver operating characteristic analysis, the fasting BDNF level had a larger area under the curve for differentiating CKD (0.645, 95% CI 0.583‒0.707) than the BDNF levels at both 30 min (0.547, 95% CI 0.481‒0.612) and 120 min (0.598, 95% CI 0.536‒0.661). A significantly lower CKD prevalence (odds ratio = 0.30, 95% CI 0.12‒0.71) was observed in the highest quartile of fasting BDNF level than that in the lowest quartile, whereas no interquartile differences were observed for BDNF levels determined at 30 or 120 min during the OGTT. Furthermore, BDNF-associated variants, including rs12098908, rs12577517, and rs72891405, were significantly associated with CKD.

CONCLUSIONS

The BDNF level at fasting, but not at 30 and 120 min after glucose intake, was an independent indicator of CKD. In addition, significant associations were observed between three BDNF gene variants and CKD.

Brain-Derived Neurotrophic Factor: A Novel Dynamically Regulated Therapeutic Modulator in Neurological Disorders

The growth factor brain-derived neurotrophic factor (BDNF), and its receptor tropomyosin-related kinase receptor type B (TrkB) play an active role in numerous areas of the adult brain, where they regulate the neuronal activity, function, and survival. Upregulation and downregulation of BDNF expression are critical for the physiology of neuronal circuits and functioning in the brain. Loss of BDNF function has been reported in the brains of patients with neurodegenerative or psychiatric disorders. This article reviews the BDNF gene structure, transport, secretion, expression and functions in the brain. This article also implicates BDNF in several brain-related disorders, including Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, major depressive disorder, schizophrenia, epilepsy and bipolar disorder.

Development and validation of brain-derived neurotrophic factor measurement in human urine samples as a non-invasive effect biomarker

Background

Brain-derived neurotrophic factor (BDNF), a neurotrophic growth factor mainly expressed in the brain, has been proposed as a potential effect biomarker; that is, as a measurable biomarker whose values could be associated with several diseases, including neurological impairments. The European Human Biomonitoring Initiative (HBM4EU) has also recognized effect biomarkers as a useful tool for establishing link between exposure to environmental pollutants and human health. Despite the well-establish protocol for measuring serum BDNF, there is a need to validate its assessment in urine, a non-invasive sample that can be easily repeated over time. The aim of this study was to develop, standardize and validate a methodology to quantify BDNF protein levels in urine samples before its implementation in biomonitoring studies.

Methods

Different experimental conditions and non-competitive commercial enzyme-linked immunosorbent assay (ELISA) kits were tested to determine the optimal analytical procedure, trying to minimize the shortcomings of ELISA kits. The fine-tune protocol was validated in a pilot study using both upon awakening (n = 150) and prior to sleeping (n = 106) urine samples from the same Spanish adolescent males in a well-characterized study population (the Spanish INMA-Granada cohort).

Results

The best results were obtained in 0.6 ml of urine after the acidification and extraction (pre-concentration) of samples. The highest reproducibility was obtained with the ELISA kit from Raybiotech. Urinary BDNF concentrations of adolescent males were within the previously reported range (morning = 0.047-6.801 ng/ml and night = 0.047-7.404 ng/ml). Urinary BDNF levels in the awakening and pre-sleep samples did not follow a normal distribution and were not correlated.

Conclusion

The developed methodology offers good sensitivity and reproducibility. Having reliable markers in urine may facilitate both diagnosis and monitoring possible diseases (and treatment). Further studies are needed to implement urinary BDNF in biomonitoring studies to further elucidate its usefulness and biological significance for neurological impairments.

Preoperative serum brain-derived neurotrophic factor as a predictive biomarker for sepsis after living-donor liver transplantation

AIM

Although the survival rate after living-donor liver transplantation (LDLT) is improving, sepsis still limits the prognosis. Immune dysfunction and sarcopenia are often observed in LDLT patients, and increase susceptibility to infection. Brain-derived neurotrophic factor (BDNF) is a myokine produced by immune cells and skeletal muscle. We aimed to determine whether serum BDNF could be a feasible biomarker for sepsis of LDLT patients.

METHODS

We measured serum samples from 124 patients who underwent LDLT and 9 healthy volunteers for BDNF. We examined its correlation with incidence rate of sepsis. To clarify the source of BDNF, we examined its expression in lymphocytes, skeletal muscle cells, and hepatocytes.

RESULTS

Patients who experienced sepsis showed worse short-term survival. Preoperative serum BDNF was lower in LDLT patients compared with healthy volunteers, and was also lower in Child-Pugh C compared with Child-Pugh A or B. Serum BDNF was inversely correlated with Model for End-Stage Liver Disease and controlling nutritional status (CONUT) scores, but had a weak positive correlation with skeletal muscle mass index (SMI). Multivariate analysis revealed that serum BDNF was independently associated with sepsis. Preoperative serum BDNF was a better predictor of sepsis in LDLT patients than CONUT score or SMI. Serum BDNF was positively correlated with lymphocyte counts, especially T cells. In vitro, T cells and skeletal muscle cells produced BDNF.

CONCLUSIONS

Preoperative serum BDNF could be a predictive biomarker for sepsis after LDLT, by reflecting the systemic condition including hepatic function, nutritional status, and immune status.

Function of brain-derived neurotrophic factor in the hypothalamus: Implications for depression pathology

Depression is a prevalent mental health disorder and is the number one cause of disability worldwide. Risk factors for depression include genetic predisposition and stressful life events, and depression is twice as prevalent in women compared to men. Both clinical and preclinical research have implicated a critical role for brain-derived neurotrophic factor (BDNF) signaling in depression pathology as well as therapeutics. A preponderance of this research has focused on the role of BDNF and its primary receptor tropomyosin-related kinase B (TrkB) in the cortex and hippocampus. However, much of the symptomatology for depression is consistent with disruptions in functions of the hypothalamus including changes in weight, activity levels, responses to stress, and sociability. Here, we review evidence for the role of BDNF and TrkB signaling in the regions of the hypothalamus and their role in these autonomic and behavioral functions associated with depression. In addition, we identify areas for further research. Understanding the role of BDNF signaling in the hypothalamus will lead to valuable insights for sex- and stress-dependent neurobiological underpinnings of depression pathology.

Molecular Mechanisms of Exercise in Brain Disorders: a Focus on the Function of Brain-Derived Neurotrophic Factor-a Narrative Review

The natural aging process as well as many age-related diseases is associated with impaired metabolic adaptation and declined ability to cope with stress. As major causes of disability and morbidity during the aging process, brain disorders, including psychiatric and neurodegenerative disorders, are likely to increase across the globe in the future decades. This narrative review investigates the link among exercise and brain disorders, aging, and inflammatory biomarkers, along with the function of brain-derived neurotrophic factor. For this study, related manuscript from all databases, Google scholar, Scopus, PubMed, and ISI were assessed. Also, in the search process, the keywords of exercise, neurodegeneration, neurotrophin, mitochondrial dysfunction, and aging were used. Mitochondrial abnormality increases neuronal abnormality and brain disease during the aging process. Stress and inflammatory factors caused by lifestyle and aging also increase brain disorders. Evidences suggest that exercise, as a noninvasive treatment strategy, has antioxidant effects and can reduce neuronal lesions. Brain-derived neurotrophic factor expression following the exercise can reduce brain symptoms; however, careful consideration should be given to a number of factors affecting the results.

Exercise Training Enhances BDNF/TrkB Signaling Pathway and Inhibits Apoptosis in Diabetic Cerebral Cortex

This study aimed to clarify the therapeutic effects of exercise training on neural BDNF/TrkB signaling and apoptotic pathways in diabetic cerebral cortex. Thirty-six male C57BL/6JNarl mice were randomly divided into three groups: control (CON-G), diabetic group (DM-G, 100 mg/kg streptozotocin, i.p.), and diabetic with exercise training group (DMEX-G, Swim training for 30 min/day, 5 days/week). After 12 weeks, H&E staining, TUNEL staining, and Western blotting were performed to detect the morphological changes, neural apoptosis, and protein levels in the cerebral cortex. The Bcl2, BclxL, and pBad were significant decreased in DM-G compared with CON-G, whereas they (excluded the Ras and pRaf1) were increased in DMEX-G. In addition, interstitial space and TUNEL(+) apoptotic cells found increased in DM-G with increases in Fas/FasL-mediated (FasL, Fas, FADD, cleaved-caspase-8, and cleaved-caspase-3) and mitochondria-initiated (tBid, Bax/Bcl2, Bak/BclxL, Bad, Apaf1, cytochrome c, and cleaved-caspase-9) apoptotic pathways. However, diabetes-induced neural apoptosis was less in DMEX-G than DM-G with observed raises in the BDNF/TrkB signaling pathway as well as decreases in Fas/FasL-mediated and mitochondria-initiated pathways. In conclusion, exercise training provided neuroprotective effects via enhanced neural BDNF/TrkB signaling pathway and prevent Fas/FasL-mediated and mitochondria-initiated apoptotic pathways in diabetic cerebral cortex.

The regulation of adipokines related to obesity and diabetes is sensitive to BDNF levels and adipose tissue location

PURPOSE

The role of BDNF in adipose tissue metabolism is poorly understood. We investigated the effects of decreased levels of BDNF on the expression of major adipokines in different fat depots (e.g., subcutaneous and epididymal) of mouse groups fed three different diet protocols.

METHODS

BDNF heterozygous (+ / -) mice were used to evaluate the effect of reduced BDNF levels. Six groups of C57BL/6 J breed wild type (WT) and BDNF (+ / -) mice were formed. These groups were fed, respectively, a control diet (CD), a high-fat diet (HFD), and a high-sucrose diet (HSD) for 4 months. Serum samples and adipose tissues were used for biochemical assays. The serum concentrations and tissue expression levels of leptin, adiponectin, and resistin were measured.

RESULTS

Compared to the CD-fed WT group (control group), serum leptin and leptin expression levels were found to be higher in all experimental groups. Serum adiponectin levels were lower in the BDNF (+ / -) groups and HFD-fed WT group than in the control group. Epididymal adiponectin expression was found to be lower in the HFD-fed BDNF (+ / -) group and higher in HSD-fed groups than in the control group. Compared to the control group, adiponectin expression increased in the WT groups in subcutaneous adipose tissue. Serum resistin levels were elevated in the HFD-fed groups. Resistin expression in epididymal adipose tissue was lower in the CD-fed and HFD-fed groups than in the control group.

CONCLUSIONS

BDNF levels and diet differentially affect the expression of adipokines in different fat tissues in the body. BDNF may play a protective role in obesity and diabetes.

Salivary Neurotrophins Brain-Derived Neurotrophic Factor and Nerve Growth Factor Associated with Childhood Obesity: A Multiplex Magnetic Luminescence Analysis

Obesity is linked with higher inflammatory markers and is characterized by chronic low-grade inflammation. Neurotrophins brain-derived neurotrophic factor (BDNF) and β-nerve growth factor (β-NGF), in addition to their neuronal functions, act on several immune cells and have been recently designated as metabokines due to their regulatory role in energy homeostasis and food intake. The current study evaluates the salivary BDNF and β-NGF and their association with anthropometric measurement, blood pressure, and salivary insulin in children. Anthropometric measurements and saliva samples were obtained from 76 children, aged 6–10 years. Multiplex analysis was carried out for the salivary analysis of BDNF, NGF, and insulin by human magnetic Luminex performance assay. Statistical analysis was performed to analyze the best fit diagnostic value for biomarkers and the relationship of the neurotrophic levels of BDNF and NGF with obesity measures and blood pressure. Salivary BDNF and β-NGF showed a significantly higher concentration in obese children than normal-weight children. Both neurotrophins are positively associated with obesity anthropometric measures, blood pressure, and salivary insulin. Multinominal regression analysis reported a significant association between salivary BDNF, β-NGF, insulin, and systolic pressure adjusted for age, gender, income, and maternal education. The salivary concentration of BDNF and NGF was higher in obese children, and it is positively associated with anthropometric measures, suggesting that neurotrophins can be used as a non-invasive predictor of obesity-related complications in children.

Neuroprotective substances: are they able to protect the pancreatic beta-cells too?

BACKGROUND

Growing evidences demonstrate a close relationship between type 2 diabetes (T2D) and neurodegenerative disorders such as Alzheimer's disease. The similarity of physiological and pathological processes, occurring in pancreatic β-cells and neurons over the course of these pathologies, allows to raise the question of the practicability of studying neuroprotective substances for their potential antidiabetic activity.

OBJECTIVE

This review analyzes studies of antidiabetic and cytoprotective action on pancreatic β-cells of the neuroprotective compounds that can attenuate the oxidative stress and enhance the expression of neurotrophins: low-molecular-weight NGF mimetic compound GK-2, selective anxiolytic afobazole, antidepressants lithium chloride and lithium carbonate on the rat streptozotocin model of T2D.

RESULTS

It was found that all above-listed neuroprotective substances have a pronounced antidiabetic activity. The decrease in the β-cells number, the average area of the pancreatic islets, as well as the violation of their morphological structure caused by the streptozotocin was significantly weakened by the therapy with the investigated neuroprotective substances. The extent of these morphological changes clearly correlates with the antihyperglycemic effect of these compounds.

CONCLUSION

The presented data indicate that the neuroprotective substances attenuating the damaging effect of oxidative stress and neurotrophins deficit cannot only protect neurons but also exert their cytoprotective effect towards pancreatic β-cells. These data may provide a theoretical basis for the further study of neuroprotective drugs as potential therapeutic options for T2D prevention and treatment.

Methylation Status of Exon IV of the Brain-Derived Neurotrophic Factor (BDNF)-Encoding Gene in Patients with Non-Diabetic Hyperglycaemia (NDH) before and after a Lifestyle Intervention

BDNF signalling in hypothalamic neuronal circuits is thought to regulate mammalian food intake. In light of this, we investigated how a lifestyle intervention influenced serum levels and DNA methylation of BDNF gene in fat tissue and buffy coat of NDH individuals. In total, 20 participants underwent anthropometric measurements/fasting blood tests and adipose tissue biopsy pre-/post-lifestyle (6 months) intervention. DNA was extracted from adipose tissue and buffy coat, bisulphite converted, and pyrosequencing was used to determine methylation levels in exon IV of the BDNF gene. RNA was extracted from buffy coat for gene expression analysis and serum BDNF levels were measured by ELISA. No differences were found in BDNF serum levels, but buffy coat mean BDNF gene methylation decreased post-intervention. There were correlations between BDNF serum levels and/or methylation and cardiometabolic markers. (i) Pre-intervention: for BDNF methylation, we found positive correlations between mean methylation in fat tissue and waist-hip ratio, and negative correlations between mean methylation in buffy coat and weight. (ii) Post-intervention: we found correlations between BDNF mean methylation in buffy coat and HbA1c, BDNF methylation in buffy coat and circulating IGFBP-2, and BDNF serum and insulin. Higher BDNF % methylation levels are known to reduce BNDF expression. The fall in buffy coat mean BDNF methylation plus the association between lower BDNF methylation (so potentially higher BDNF) and higher HbA1c and serum IGFBP-2 (as a marker of insulin sensitivity) and between lower serum BDNF and higher circulating insulin are evidence for the degree of BDNF gene methylation being implicated in insulinisation and glucose homeostasis, particularly after lifestyle change in NDH individuals.

mRNA Expressions of Methylation Related Enzymes and Duration of Thermal Conditioning in Chicks

DNA methylation regulates gene expression by modifying the nucleosome structure of DNA, without altering the gene sequence. It has been reported that DNA methylation reactions are catalyzed by several enzymes. In chickens, thermal conditioning treatment affects the central DNA methylation levels. The purpose of this study was to clarify the changes in DNA methylation and demethylation factors during thermal conditioning in the hypothalamus of 3-day-old chicks. Male chicks (3-days old) were exposed to 40±0.5°C as a thermal conditioning treatment for 1, 2, 6, 9, or 12 h. The control chicks were kept in a thermoneutral zone (30±0.2°C). After thermal conditioning, the mRNA levels of DNA methyltransferase (DNMT)-1, -3a, -3b, and ten-eleven translocation (TET)-1, -2, and -3 in the hypothalamus were measured by q-PCR. The mRNA levels of DNMT-3a and TET-1 were increased by thermal conditioning. Moreover, the expression level of TET-1 increased with the loading time of the thermal conditioning. The gene expressions of DNMT-1, DNMT-3b, TET-2, and TET-3 were not affected by thermal conditioning. Since DNMT-3a is a catalyst for de-novo DNA methylation and TET-1 catalyzes the oxidation of methylated cytosine, it is suggested that the thermal conditioning increased the activation of DNA methylation and demethylation factors, which occur in the hypothalamus of neonatal chicks.

Effects of a Novel Magnesium Complex on Metabolic and Cognitive Functions and the Expression of Synapse-Associated Proteins in Rats Fed a High-Fat Diet

This study was conducted to compare the effects of a novel form of magnesium, Mg picolinate (MgPic), to magnesium oxide (MgO) on metabolic and cognitive functions and the expression of genes associated with these functions in rats fed a high-fat diet (HFD). Forty-two Wistar rats were divided into six groups: control, MgO, MgPic, HFD, HFD + MgO, and HFD + MgPic. Mg was supplemented at 500 mg of elemental Mg/kg diet for 8 weeks. MgPic and MgO supplementation decreased visceral fat, serum glucose, insulin, leptin, TC, TG, FFA, testosterone, FSH, LH, SHBG, IGF-1, and MDA levels, but increased brain SOD, CAT, and GSH-Px activities in HFD rats. Inflammation and cognitive-related markers (presynaptic synapsin PSD95, postsynaptic PSD93, postsynaptic GluR1, and GluR2) were improved in HFD rats administered Mg, with more significant effects seen in the MgPic group. MgPic also decreased brain NF-κB but elevated brain Nrf2 levels, compared with the HFD group. The phosphorylation levels of Akt (Thr308), Akt (Ser473), PI3K try 458/199, and Ser9-GSK-3 in the brain were improved after Mg treatment in HFD rats, with more potent effects seen from MgPic supplementation. MgPic has a higher bioavailability and is more effective in improving metabolic parameters and enhancing memory than MgO. The pro-cognitive effects of MgO and MgPic could be mediated via modulation of the AMPA-type glutamate receptor and activation of the PI3K-Akt-GSK-3β signaling pathway. These findings further support the use of MgPic in the management of metabolic and cognitive disorders.

The Pleiotropic Potential of BDNF beyond Neurons: Implication for a Healthy Mind in a Healthy Body

Brain-derived neurotrophic factor (BDNF) represents one of the most widely studied neurotrophins because of the many mechanisms in which it is involved. Among these, a growing body of evidence indicates BDNF as a pleiotropic signaling molecule and unveils non-negligible implications in the regulation of energy balance. BDNF and its receptor are extensively expressed in the hypothalamus, regions where peripheral signals, associated with feeding control and metabolism activation, and are integrated to elaborate anorexigenic and orexigenic effects. Thus, BDNF coordinates adaptive responses to fluctuations in energy intake and expenditure, connecting the central nervous system with peripheral tissues, including muscle, liver, and the adipose tissue in a complex operational network. This review discusses the latest literature dealing with the involvement of BDNF in the maintenance of energy balance. We have focused on the physiological and molecular mechanisms by which BDNF: (I) controls the mitochondrial function and dynamics; (II) influences thermogenesis and tissue differentiation; (III) mediates the effects of exercise on cognitive functions; and (IV) modulates insulin sensitivity and glucose transport at the cellular level. Deepening the understanding of the mechanisms exploited to maintain energy homeostasis will lay the groundwork for the development of novel therapeutical approaches to help people to maintain a healthy mind in a healthy body.

BDNF levels in adolescent patients with anorexia nervosa increase continuously to supranormal levels 2.5 years after first hospitalization

BACKGROUND

Brain-derived neurotrophic factor (BDNF) influences brain plasticity and feeding behaviour, and it has been linked to anorexia nervosa in numerous studies. Findings in mostly adult patients point to reduced serum BDNF levels in the acute stage of anorexia nervosa and rising levels with weight recovery. However, it is unclear whether this increase leads to normalization or supranormal levels, a difference that is potentially important for the etiology of anorexia nervosa and relapse.

METHODS

We measured serum BDNF at admission (n = 149), discharge (n = 130), 1-year follow-up (n = 116) and 2.5-year follow-up (n = 76) in adolescent female patients with anorexia nervosa hospitalized for the first time, and in healthy controls (n = 79). We analyzed associations with body mass index, eating disorder psychopathology and comorbidities.

RESULTS

Serum BDNF was only nominally lower at admission in patients with anorexia nervosa compared to healthy controls, but it increased continuously and reached supranormal levels at 2.5-year follow-up. BDNF was inversely associated with eating disorder psychopathology at discharge and positively associated with previous weight gain at 1-year follow-up.

LIMITATIONS

We compensated for attrition and batch effects using statistical measures.

CONCLUSION

In this largest longitudinal study to date, we found only nonsignificant reductions in BDNF in the acute stage of anorexia nervosa, possibly because of a shorter illness duration in adolescent patients. Supranormal levels of BDNF at 2.5-year follow-up could represent a pre-existing trait or a consequence of the illness. Because of the anorexigenic effect of BDNF, it might play an important predisposing role for relapse and should be explored further in studies that test causality.

Hijacking Dorsal Raphe to Improve Metabolism and Depression-Like Behaviors via BDNF Gene Transfer in Mice

Moods and metabolism modulate each other. High comorbidity of depression and metabolic disorders, such as diabetes and obesity, poses a great challenge to treat such conditions. Here we report the therapeutic efficacy of brain-derived neurotrophic factor (BDNF) by gene transfer in the dorsal raphe nucleus (DRN) in a chronic unpredictable mild stress model (CUMS) of depression and models of diabetes and obesity. In CUMS, BDNF-expressing mice displayed antidepressant- and anxiolytic-like behaviors, which are associated with augmented serotonergic activity. Both in the diet-induced obesity model (DIO) and in db/db mice, BDNF ameliorated obesity and diabetes, which may be mediated by enhanced sympathetic activity not involving DRN serotonin. Chronic activation of DRN neurons via chemogenetic tools produced similar effects as BDNF in DIO mice. These results established the DRN as a key nexus in regulating depression-like behaviors and metabolism, which can be exploited to combat comorbid depression and metabolic disorders via BDNF gene transfer.

BDNF and pro-BDNF in serum and exosomes in major depression: Evolution after antidepressant treatment

BACKGROUND

The study of clinically related biological indicators in Major Depression (MD) is important. The Brain Derived Neurotrophic Factor (BDNF) appears to play an important role in MD, through its neurotrophic effect, and its levels are significantly decreased. The variation in the serum levels of its precursor proBDNF, which has opposite effects, is not known. Their distribution between serum and exosomes and their evolution during antidepressant treatment is also not known, and may be important in modulating their effects. The aim of this study is to evaluate whether serum and exosome mBDNF and proBDNF levels are altered in patients with MD during antidepressant treatment compared to controls, and their association with clinical improvement and clinical variables.

MATERIALS AND METHODS

42 MD subjects and 40 controls were included. Questionnaires to assess the severity of depression and cognitive impairment and blood samples were collected during the three visits at D0 (inclusion) and 3 and 7 weeks after the start of antidepressant treatment. Assays for mBDNF and proBDNF levels were performed in serum and exosomes by ELISA.

RESULTS

MD subjects had decreased serum and exosomal BDNF levels and increased proBDNF levels at D0 compared to controls. BDNF and pro-BDNF vary in an inverse manner in both serum and exosomes during antidepressant treatment. No relationship of BDNF and proBDNF levels to clinical improvement and depression scales was found.

CONCLUSION

We demonstrated an evolution of those molecules either in serum or in exosomes after MD treatment. These transport vesicles could have a role in the regulation of BDNF.

Effect of four different forms of high intensity training on BDNF response to Wingate and Graded Exercise Test

This study examined the effects of a nine-week intervention of four different high-intensity training modalities [high-intensity functional training (HIFT), high-intensity interval training (HIIT), high-intensity power training (HIPT), and high-intensity endurance training (HIET)] on the resting concentration of brain-derived neurotropic factor (BDNF). In addition, we evaluated the BDNF responses to Graded Exercise Test (GXT) and Wingate Anaerobic Test (WAnT) in men. Thirty-five healthy individuals with body mass index 25.55 ± 2.35 kg/m2 voluntarily participated in this study and were randomly assigned into four training groups. During nine-weeks they completed three exercise sessions per week for one-hour. BDNF was analyzed before and after a GXT and WAnT in two stages: (stage 0-before training and stage 9-after nine weeks of training). At stage 0, an increase in BDNF concentration was observed in HIFT (33%; p < 0.05), HIPT (36%; p < 0.05) and HIIT (38%; p < 0.05) after GXT. Even though HIET showed an increase in BDNF (10%) this was not statistically significant (p > 0.05). At stage 9, higher BDNF levels after GXT were seen only for the HIFT (30%; p < 0.05) and HIIT (18%; p < 0.05) groups. Reduction in BDNF levels were noted after the WAnT in stage 0 for HIFT (- 47%; p < 0.01), HIPT (- 49%; p < 0.001), HIET (- 18%; p < 0.05)], with no changes in the HIIT group (- 2%). At stage 9, BDNF was also reduced after WAnT, although these changes were lower compared to stage 0. The reduced level of BDNF was noted in the HIFT (- 28%; p < 0.05), and HIPT (- 19%;p < 0.05) groups. Additionally, all groups saw an improvement in VO2max (8%; p < 0.001), while BDNF was also correlated with lactate and minute ventilation and selected WAnT parameters. Our research has shown that resting values of BDNF after nine weeks of different forms of high-intensity training (HIT) have not changed or were reduced. Resting BDNF measured at 3th (before GXT at stage 9) and 6th day after long lasting HITs (before WAnT at stage 9) did not differed (before GXT), but in comparison to the resting value before WAnT at the baseline state, was lower in three groups. It appears that BDNF levels after one bout of exercise is depended on duration time, intensity and type of test/exercise.

Discovery of pyrazolo-thieno[3,2-d]pyrimidinylamino-phenyl acetamides as type-II pan-tropomyosin receptor kinase (TRK) inhibitors: Design, synthesis, and biological evaluation

Tropomyosin receptor kinase (TRK) represents an attractive oncology target for cancer therapy related to its critical role in cancer formation and progression. NTRK fusions are found to occur in 3.3% of lung cancers, 2.2% of colorectal cancers, 16.7% of thyroid cancers, 2.5% of glioblastomas, and 7.1% of pediatric gliomas. In this paper, we described the discovery of the type-II pan-TRK inhibitor 4c through the structure-based drug design strategy from the original hits 1b and 2b. Compound 4c exhibited excellent in vitro TRKA, TRKB, and TRKC kinase inhibitory activity and anti-proliferative activity against human colorectal carcinoma derived cell line KM12. In the NCI-60 human cancer cell lines screen, compound 4g demonstrated nearly 80% of growth inhibition for KM12, while only minimal inhibitory activity was observed for the remaining 59 cancer cell lines. Western blot analysis demonstrated that 4c and its urea cousin 4k suppressed the TPM3-TRKA autophosphorylation at the concentrations of 100 nM and 10 nM, respectively. The work presented that 2-(4-(thieno[3,2-d]pyrimidin-4-ylamino)phenyl)acetamides could serve as a novel scaffold for the discovery and development of type-II pan-TRK inhibitors for the treatment of TRK driven cancers.

Deletion of the Brain-Specific α and δ Isoforms of Adapter Protein SH2B1 Protects Mice From Obesity

Mice lacking SH2B1 and humans with variants of SH2B1 display severe obesity and insulin resistance. SH2B1 is an adapter protein that is recruited to the receptors of multiple hormones and neurotrophic factors. Of the four known alternatively spliced SH2B1 isoforms, SH2B1β and SH2B1γ exhibit ubiquitous expression, whereas SH2B1α and SH2B1δ are essentially restricted to the brain. To understand the roles for SH2B1α and SH2B1δ in energy balance and glucose metabolism, we generated mice lacking these brain-specific isoforms (αδ knockout [αδKO] mice). αδKO mice exhibit decreased food intake, protection from weight gain on standard and high-fat diets, and an adiposity-dependent improvement in glucose homeostasis. SH2B1 has been suggested to impact energy balance via the modulation of leptin action. However, αδKO mice exhibit leptin sensitivity that is similar to that of wild-type mice by multiple measures. Thus, decreasing the abundance of SH2B1α and/or SH2B1δ relative to the other SH2B1 isoforms likely shifts energy balance toward a lean phenotype via a primarily leptin-independent mechanism. Our findings suggest that the different alternatively spliced isoforms of SH2B1 perform different functions in vivo.

BDNF influences neural cue-reactivity to food stimuli and food craving in obesity

There is increasing evidence that brain-derived neurotrophic factor (BDNF) impacts on the development of obesity. We are the first to test the hypothesis that BDNF levels might be associated with neural reactivity to food cues in patients suffering from obesity and healthy controls. We assessed visual food cue-induced neural response in 19 obese patients and 20 matched controls using functional magnetic resonance imaging and analyzed the associations between BDNF levels, food cue-reactivity and food craving. Whole-brain analysis in both groups revealed that food cues elicited higher neural activation in clusters of mesolimbic brain areas including the insula (food > neutral). Patients suffering from obesity showed a significant positive correlation between plasma BDNF levels and visual food cue-reactivity in the bilateral insulae. In addition, patients suffering from obesity with positive food cue-induced insula activation also reported significantly higher food craving than those with low cue-reactivity-an effect that was absent in normal weight participants. The present findings implicate that BDNF levels in patients suffering from obesity might be involved in food craving and obesity in humans. This highlights the importance to consider BDNF pathways when investigating obesity and obesity treatment.

The Relation of the Brain-Derived Neurotrophic Factor with MicroRNAs in Neurodegenerative Diseases and Ischemic Stroke

Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family of growth factors that plays a crucial role in the development of the nervous system while supporting the survival of existing neurons and instigating neurogenesis. Altered levels of BDNF, both in the circulation and in the central nervous system (CNS), have been reported to be involved in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD), multiple sclerosis (MS), and ischemic stroke. MicroRNAs (miRNAs) are a class of non-coding RNAs found in body fluids such as peripheral blood and cerebrospinal fluid. Several different miRNAs, and their target genes, are recognized to be involved in the pathophysiology of neurodegenerative and neurovascular diseases. Thus, they present as promising biomarkers and a novel treatment approach for CNS disorders. Currently, limited studies provide viable evidence of miRNA-mediated post-transcriptional regulation of BDNF. The aim of this review is to provide a comprehensive assessment of the current knowledge regarding the potential diagnostic and prognostic values of miRNAs affecting BDNF expression and its role as a CNS disorders and neurovascular disease biomarker. Moreover, a novel therapeutic approach in neurodegenerative diseases and ischemic stroke targeting miRNAs associated with BDNF will be discussed.

Two Months of Using Global Recommendations for Physical Activity Had No Impact on Cognitive or Motor Functions in Overweight and Obese Middle-Aged Women

BACKGROUND

The effect of globally recommended levels of physical activity on cognition and motor behavior is not completely understood. Therefore, the main aim of this study was to assess the effect of 300 minutes per week of moderate-intensity aerobic exercise on cognitive and motor performance among overweight and obese working-age women.

METHODS

Overweight and obese participants aged 38-56 years were randomized to either a control or an experimental group performing aerobic exercise at 50% to 60% of the peak oxygen consumption for a 2-month period. Changes in aerobic fitness, cardiac autonomic function, brain-derived neurotropic factor levels, and cognitive and motor performance were assessed.

RESULTS

Although aerobic exercise reduced body weight (P < .05) and improved peak oxygen consumption (P < .05), the brain-derived neurotropic factor levels and cognitive and motor performance remained unchanged. Heart rate and blood pressure decreased (P < .05), whereas heart rate variability indices were not affected. No significant correlations between changes in heart rate variability indices and cognition were observed.

CONCLUSIONS

Two months of moderate-intensity aerobic exercise decreased sympathetic activity and improved cardiovascular fitness but had no impact on cognition or motor control among these middle-aged, overweight, and obese women.

Effects of Cerebrolysin on Hippocampal Neuronal Death After Pilocarpine-Induced Seizure

Epilepsy is one of the most common and severe brain diseases. The exact cause of epilepsy is unclear. Epilepsy often occurs following brain damage, such as traumatic brain injury (TBI) and ischemia. Cerebrolysin is a porcine brain peptide that is a unique neurotropic and neuroprotective agent. Cerebrolysin has been reported to increase neuroprotective effects after TBI, ischemia, and other CNS diseases. However, the effects of cerebrolysin on seizures are not known. Therefore, this study aimed to investigate the effects of neuropeptide cerebrolysin on neuronal death in the hippocampus after a seizure. To confirm the effects of cerebrolysin, we used a pilocarpine-induced seizure animal model. Cerebrolysin (2.5 ml/kg, i.p., once per day for 7 days) was immediately injected after a seizure induction. After 1 week, we obtained brain tissues and performed staining to histologically evaluate the potentially protective effects of cerebrolysin on seizure-induced neuronal death in the hippocampus. We found that cerebrolysin decreased hippocampal neuronal death after a seizure. In addition, an increase in brain-derived neurotrophic factor (BDNF) was confirmed through Western blot analysis to further support our hypothesis. Therefore, the present study suggests that the administration of cerebrolysin can be a useful therapeutic tool for preventing neuronal death after a seizure.

Repeated thermal conditioning during the neonatal period affects behavioral and physiological responses to acute heat stress in chicks

OBJECTIVE

The aim of the present study was to investigate the effects of repeated thermal conditioning (RTC) at an early age on physiological and behavioral responses in chicks.

METHODS

Birds were assigned to one of the four treatments in which the RTC was exposure to 40 °C for 15 min daily. The treatments were 1) no thermal conditioning (control); 2) early exposure group (EE; RTC from 2 to 4 days of age); 3) later exposure group (LE; RTC from 5 to 7 days of age); or 4) both early and later exposure (BE; RTC from 2 to 7 days of age). All groups of chicks were challenged with high ambient temperature (40 °C for 15 min) at two weeks of age.

RESULTS

During heat challenge, initiation times of dissipation behaviors (panting and wing-drooping) were measured. Rectal temperature and respiration rate were measured after and before heat challenge. Hypothalamic samples and blood were collected at the end of heat challenges. Initiation times of dissipation behaviors and rectal temperature were not affected by the treatments. Increases in respiration rate in response to heat challenge were suppressed by early RTC treatment. There was no clear pattern of glucose levels in relation to thermal conditioning, whereas plasma corticosterone levels were decreased by early treatment (EE and BE groups). Hypothalamic thyrotropin releasing hormone gene expression was suppressed by early and later thermal conditioning and suppressed further by both early and later exposure. Neuropeptide Y gene expression in the BE group was lower than in the other groups, with a similar trend for corticotropin releasing hormone expression.

CONCLUSION

Our results suggest that the effect of repeated thermal conditioning on the central thermoregulatory system depends on the number of times that chicks experienced conditioning. In addition, repeated thermal conditioning has greater effects on the acquisition of thermotolerance when conditioning occurs in chicks of two to four days of age in comparison with chicks of five to seven days of age.

Early life exposure to hypercaloric diet impairs eating behavior during weaning: The role of BDNF signaling and astrocyte marks

Literature shows that gestational and/or lactational exposure to hypercaloric diets induces long term effects on eating behavior and the involvement of neurochemical mechanisms. We hypothesized that the effects of hypercaloric diets in early development phases can precede an overweight or an obesity status. The aim of the present study was to evaluate the impact of gestational and lactational exposure to cafeteria diet on eating behavior and neurochemical parameters, BDNF signaling, epigenetic and astrocyte marks in the hippocampus and olfactory bulb during the weaning phase. Pregnant female rats were randomized between standard and cafeteria diet, the respective diet was maintained through the lactational period. The framework of feeding pattern, meal, and its microstructure, was observed in postnatal day 20. Exposure to cafeteria diet increased the number of meals, associated with a lower first inter-meal interval and higher consumption in both genders, without any changes in body weight. Diet exposure also reduced the number of grooming, a behavior typically found at the end of meals. Hypercaloric diet exposure reduced BDNF levels in the olfactory bulb and hippocampus from rats of both sexes and increased the content of the TrkB receptor in hippocampi. It was observed an increase in HDAC5 levels, an epigenetic mark. Still, early exposure to the hypercaloric diet reduced hippocampal GFAP and PPARγ levels, without any effect on NeuN content, indicating that alterations in astrocytes can precede those neuronal outcomes. Our results showed that changes in interrelated neurochemical signaling, BDNF, and astrocyte marks, induced by hypercaloric diet in early stages of development may be related to impairment in the temporal distribution of eating pattern and consequent amounts of consumed food during the weaning phase.

Interplay between Peripheral and Central Inflammation in Obesity-Promoted Disorders: The Impact on Synaptic Mitochondrial Functions

The metabolic dysfunctions induced by high fat diet (HFD) consumption are not limited to organs involved in energy metabolism but cause also a chronic low-grade systemic inflammation that affects the whole body including the central nervous system. The brain has been considered for a long time to be protected from systemic inflammation by the blood–brain barrier, but more recent data indicated an association between obesity and neurodegeneration. Moreover, obesity-related consequences, such as insulin and leptin resistance, mitochondrial dysfunction and reactive oxygen species (ROS) production, may anticipate and accelerate the physiological aging processes characterized by systemic inflammation and higher susceptibility to neurological disorders. Here, we discussed the link between obesity-related metabolic dysfunctions and neuroinflammation, with particular attention to molecules regulating the interplay between energetic impairment and altered synaptic plasticity, for instance AMP-activated protein kinase (AMPK) and Brain-derived neurotrophic factor (BDNF). The effects of HFD-induced neuroinflammation on neuronal plasticity may be mediated by altered brain mitochondrial functions. Since mitochondria play a key role in synaptic areas, providing energy to support synaptic plasticity and controlling ROS production, the negative effects of HFD may be more pronounced in synapses. In conclusion, it will be emphasized how HFD-induced metabolic alterations, systemic inflammation, oxidative stress, neuroinflammation and impaired brain plasticity are tightly interconnected processes, implicated in the pathogenesis of neurological diseases.

Low-molecular mimetics of nerve growth factor and brain-derived neurotrophic factor: Design and pharmacological properties

To overcome the limitations of the clinical use of neurotrophins nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), scientists have been trying to create their low-molecular-weight mimetics having improved pharmacokinetic properties and lacking side effects of full-sized proteins since the 90s of the last century. The efforts of various research groups have led to the production of peptide and nonpeptide mimetics, being agonists or modulators of the corresponding Trk or p75 receptors that reproduced the therapeutic effects of full-sized proteins. This review discusses different strategies and approaches to the design of such compounds. The relationship between the structure of the mimetics obtained and their action mechanisms and pharmacological properties are analyzed. Special attention is paid to the dipeptide mimetics of individual NGF and BDNF loops having different patterns of activation of Trk receptors signal transduction pathways, phosphoinositide 3-kinase/protein kinase B and mitogen-activated protein kinase/extracellular signal-regulated kinase, which allowed to evaluate the contribution of each pathway to different pharmacological effects. In conclusion, data on therapeutically promising compounds being at different stages of preclinical and clinical studies are summarized.

A 10-week yoga practice has no effect on cognition, but improves balance and motor learning by attenuating brain-derived neurotrophic factor levels in older adults

Despite studies investigating the effect of yoga on cognitive and motor functioning in older adults, the effect on dual-task performance and motor learning and the specific mechanisms underlying the positive effect of yoga remain unclear. Thus, the aim of this study was to investigate the effects of yoga on cognition, balance under single- and dual-task conditions, and motor learning. The potential role of brain-derived neurotrophic factor (BDNF) in induced improvement was also explored. Participants aged 60-79 years were randomized to either a control group (n = 15) or a yoga group (n = 18) for a 10-week period. The yoga group received 90-min duration yoga classes two times per week. Changes in cognition, balance under single- and dual-task conditions, and learning fast and accurate reaching movements were assessed. Yoga practice decreased (P < 0.05) the velocity vector of the center of pressure under single- and dual-task conditions, whereas no changes in cognitive performance were observed. Although reaction and movement times during learning were decreased in both groups (P < 0.05), a faster reaction time (P < 0.05) and shorter movement time (P < 0.05) were observed in the yoga group than in the control group. Significant moderate relationships (P < 0.05) between changes in BDNF levels and functional improvements were observed. Thus, 10 weeks of yoga practice resulted in improved balance and learning in the speed-accuracy motor task that were mediated by increased BDNF levels, but had no impact on cognition in older adults.

Brain-derived neurotrophic factor modulates mitochondrial dynamics and thermogenic phenotype on 3T3-L1 adipocytes

Obesity is a growing threat. In recent years, the finding of functional brown adipose tissue (BAT) in adult humans implemented the studies of anti-obesity therapies based on triggering energy expenditure. The activation of BAT thermogenesis and the recruitment of brite (brown-in-white) adipocytes are under noradrenergic control. Brain-derived neurotrophic factor (BDNF), if centrally administered, enhances thermogenesis through sympathetic activation, but its direct effect on adipocytes is still unclear. The phenotypic change from fat storing to thermogenic adipocytes is recognized by the presence of multilocular lipid droplets (LDs) and fissed mitochondria that tend to surround LDs, maximizing the efficiency of fatty acid release for thermogenesis. BDNF treatment on differentiated 3T3-L1 adipocytes was compared to negative (CTRL) and positive (norepinephrine, NE) controls. BDNF significantly increased small globular mitochondria percentage (>150% CTRL), while the area surface and elongation index of branched tubules were respectively 55% and 10% lower than NE. Canonical discriminant analysis of mitochondria morphological data clearly separated differentially treated cells with 85% of the total variance. The expression of brown markers and mitochondrial dynamic genes was significantly affected by BDNF. Investigating the pathways involved in adipocyte BDNF stimulation could clarify its role in thermogenesis and its possible local regulation.

Understanding the Physiological Links Between Physical Frailty and Cognitive Decline

Declines in both physical and cognitive function are associated with increasing age. Understanding the physiological link between physical frailty and cognitive decline may allow us to develop interventions that prevent and treat both conditions. Although there is significant epidemiological evidence linking physical frailty to cognitive decline, a complete understanding of the underpinning biological basis of the two disorders remains fragmented. This narrative review discusses insights into the potential roles of chronic inflammation, impaired hypothalamic-pituitary axis stress response, imbalanced energy metabolism, mitochondrial dysfunction, oxidative stress, and neuroendocrine dysfunction linking physical frailty with cognitive decline. We highlight the importance of easier identification of strategic approaches delaying the progression and onset of physical frailty and cognitive decline as well as preventing disability in the older population.