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

Effects of a single 10-hour daytime fasting intervention on mood and appetite in female adults with and without obesity: a real-world feasibility trial

Objective: Comparison of the effect of acute daytime fasting on mood, satiety, and neurotrophic factors in females with (OB) and without obesity (N-OB).Methods: Non-randomized single-arm feasibility trial. Data were collected at an outpatient clinic and from real-world settings. Participants were evaluated after 10 h of nocturnal fasting (T1) and following a 10-hour diurnal fasting period (T2) after consuming a standardized breakfast. Mood, subjective feelings of satiety, food cravings, and neurotrophic factors brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), and glial cell line-derived neurotrophic factor (GDNF) were assessed.Results: Fifty-four participants were enrolled in the study [mean age 31 (SD 9)]. One participant from the OB group dropped out before T2, leaving 53 participants (N-OB: n = 29, OB: n = 24). Both groups experienced increased hunger and decreased satiety and fullness after T2. Females with obesity had a greater increase in hunger (p = 0.02). Depression and anger symptoms increased in the OB group, whereas fatigue increased in the N-OB group after T2. NGF increased slightly in the N-OB group after T2, while BDNF and GDNF remained unchanged.Conclusion: Daytime fasting during daily activities affects mood and eating behavior, especially in females with obesity. Fasting interventions should be tailored to individual needs, considering these differential effects.Trial registration: ClinicalTrials.gov identifier: NCT03532672.

Nutritional considerations in major depressive disorder: current evidence and functional testing for clinical practice

Depression is a multifaceted condition with diverse underlying causes. Several contributing and inter-related factors such as genetic, nutritional, neurological, physiological, gut-brain-axis, metabolic and psychological stress factors play a role in the pathophysiology of depression. This review aims to highlight the role that nutritional factors play in the aetiology of depression. Secondly, we discuss the biomedical and functional pathology tests which measure these factors, and the current evidence supporting their use. Lastly, we make recommendations on how practitioners can incorporate the latest evidence-based research findings into clinical practice. This review highlights that diet and nutrition greatly affect the pathophysiology of depression. Nutrients influence gene expression, with folate and vitamin B12 playing vital roles in methylation reactions and homocysteine regulation. Nutrients are also involved in the tryptophan/kynurenine pathway and the expression of brain-derived neurotrophic factor (BDNF). Additionally, diet influences the hypothalamic-pituitary-adrenal (HPA) response and the composition and diversity of the gut microbiome, both of which have been implicated in depression. A comprehensive dietary assessment, combined with appropriate evaluation of biochemistry and blood pathology, may help uncover contributing factors to depressive symptoms. By employing such an approach, a more targeted and personalised treatment strategy can be devised, ultimately leading to improved patient outcomes.

Influence of the Brain-Derived Neurotrophic Factor Gene Polymorphism on Weight Loss Following Intragastric Balloon Intervention: A Cross-Sectional Study

Background and Aim

There is noticeable heterogeneity in weight loss outcomes following intragastric balloon (IGB) treatment, with average weight loss ranging between 11% to 15% of total body weight. Genetic variations associated with obesity have been found to influence weight loss response, however such variations are limited. Therefore, the aim of this study is to investigate the impact of the obesity associated brain-derived neurotrophic factor (BDNF) gene polymorphism rs11030104 with weight loss outcomes following IGB treatment.

Methods

In this cross-sectional study, BDNF rs11030104 was analysed in 106 individuals who underwent intragastric balloon treatment. Weight loss metrics were evaluated at the three-month follow-up: percentage of total weight loss (%TWL), percentage of excess weight loss (%EWL), and percentage of body mass index loss (%EBMIL). The effects of additive and dominant genetic models were evaluated. Both linear and logistic regression were applied to assess associations between rs11030104 genotypes and weight loss metrics.

Results

A total of 71 participants completed the 3-month follow-up assessment (loss to follow-up: 33%). This study found a significant association between the BDNF rs11030104 polymorphism and weight loss. A-allele carriers showed a better response to IGB treatment. Individuals carrying the AA genotype were found to have a greater %TWL than those carrying the GG genotype at 3 months post-IGB treatment (11.05% vs 5.09%, p=0.003).

Conclusion

Our results suggest that BDNF rs11030104 influences the response to weight loss after IGB treatment and therefore could be added to the growing list of genetic variants that predict greater weight loss response.

Melissa officinalis extract improved high-fat-diet-induced anxiety-like behaviors, depression, and memory impairment by regulation of serum BDNF levels in rats

Objective

Melissa officinalis (MO) hydroalcoholic extract has shown neuroprotective effects. We assess the possible therapeutic effects of Melissa officinalis extract (MOE) on blood biochemical and Brain-Derived Neurotrophic Factor (BDNF) levels as well as neurobehavioral consequences of high-fat-diet (HFD)-induced obese rats.

Materials and Methods

Eighty male Wistar rats weighing between 180 and 220 g were divided into two groups at the beginning of the experiment and fed with normal diet (ND) or HFD for 5 weeks. Then, each group was divided into four subgroups (10 rats in each group) and treated daily with MOE (50, 100, 150 mg/kg, intraperitoneal) or vehicle for another two weeks. At the end of the experiments, fasting blood glucose (FBG), blood lipid profile, and serum brain-derived neurotrophic factor (BDNF) levels were measured. The sucrose preference test (anhedonia and depression), open field test (locomotor), elevated plus maze (anxiety), Y-maze (working memory), and Morris water maze test (spatial memory) were done.

Results

Feeding with HFD for 7 weeks caused obesity, anhedonia, anxiety, depression and learning and memory disorders in rats and a decrease in serum BDNF level. Administration of MOE at 100 or 150 mg/kg to HFD-fed rats decreased weight gain, FBG, and serum levels of total low-density lipoprotein cholesterol and increased serum BDNF levels. It also improved changes in locomotor activity, anxiety, depression, and learning and memory in HFD-fed rats.

Conclusion

The results show that MOE has a therapeutic effect on model rats with HFD-induced metabolic and neurobehavioral abnormalities through regulation of BDNF secretion.

Associated between cognition, brain-derived neurotrophic factor (BDNF) and macronutrients in normal and overweight postmenopausal women

BDNF is a protein associated with cognitive dysfunction. The aim of the study was to determine the relationship between BDNF and cognitive functions and the intake of macronutrients in postmenopausal women. For this purpose, 72 postmenopausal women were recruited to the study and divided into two subgroups: overweight/obese and normal weight. Using a 3-day food record, nutrition was assessed. The markers studied were the level of BDNF, which was determined from the venous blood serum collected from women, and selected cognitive functions. We observed that in the normal BMI group macronutrient intake was correlated with BDNF levels, and only total fat and carbohydrate intake were inversely correlated with BDNF levels. There were inverse correlations observed among selected parameters of cognitive functioning. In the Ov/Ob group, macronutrient intake correlated with the BDNF level for several variables, e.g. vice versa with total protein, fat and carbohydrate intake, as well as dietary cholesterol. It has also been noted that there are links between the BDNF factor and excessive body weight.

A comprehensive review of genetic causes of obesity

BACKGROUND

Obesity is a multifactorial chronic disease with a high, increasing worldwide prevalence. Genetic causes account for 7% of the cases in children with extreme obesity.

DATA SOURCES

This narrative review was conducted by searching for papers published in the PubMed/MEDLINE, Embase and SciELO databases and included 161 articles. The search used the following search terms: "obesity", "obesity and genetics", "leptin", "Prader-Willi syndrome", and "melanocortins". The types of studies included were systematic reviews, clinical trials, prospective cohort studies, cross-sectional and prospective studies, narrative reviews, and case reports.

RESULTS

The leptin-melanocortin pathway is primarily responsible for the regulation of appetite and body weight. However, several important aspects of the pathophysiology of obesity remain unknown. Genetic causes of obesity can be grouped into syndromic, monogenic, and polygenic causes and should be assessed in children with extreme obesity before the age of 5 years, hyperphagia, or a family history of extreme obesity. A microarray study, an analysis of the melanocortin type 4 receptor gene mutations and leptin levels should be performed for this purpose. There are three therapeutic levels: lifestyle modifications, pharmacological treatment, and bariatric surgery.

CONCLUSIONS

Genetic study technologies are in constant development; however, we are still far from having a personalized approach to genetic causes of obesity. A significant proportion of the affected individuals are associated with genetic causes; however, there are still barriers to its approach, as it continues to be underdiagnosed. Video Abstract (MP4 1041807 KB).

The Role of Adipokines and Myokines in the Pathogenesis of Different Obesity Phenotypes-New Perspectives

Obesity is a characteristic disease of the twenty-first century that is affecting an increasing percentage of society. Obesity expresses itself in different phenotypes: normal-weight obesity (NWO), metabolically obese normal-weight (MONW), metabolically healthy obesity (MHO), and metabolically unhealthy obesity (MUO). A range of pathophysiological mechanisms underlie the occurrence of obesity, including inflammation, oxidative stress, adipokine secretion, and other processes related to the pathophysiology of adipose tissue (AT). Body mass index (BMI) is the key indicator in the diagnosis of obesity; however, in the case of the NWO and MONW phenotypes, the metabolic disturbances are present despite BMI being within the normal range. On the other hand, MHO subjects with elevated BMI values do not present metabolic abnormalities. The MUO phenotype involves both a high BMI value and an abnormal metabolic profile. In this regard, attention has been focused on the variety of molecules produced by AT and their role in the development of obesity. Nesfatin-1, neuregulin 4, myonectin, irisin, and brain-derived neurotrophic factor (BDNF) all seem to have protective effects against obesity. The primary mechanism underlying the action of nesfatin-1 involves an increase in insulin sensitivity and reduced food intake. Neuregulin 4 sup-presses lipogenesis, decreases lipid accumulation, and reduces chronic low-grade inflammation. Myonectin lowers the amount of fatty acids in the bloodstream by increasing their absorption in the liver and AT. Irisin stimulates the browning of white adipose tissue (WAT) and consequently in-creases energy expenditure, additionally regulating glucose metabolism. Another molecule, BDNF, has anorexigenic effects. Decorin protects against the development of hyperglycemia, but may also contribute to proinflammatory processes. Similar effects are shown in the case of visfatin and chemerin, which may predispose to obesity. Visfatin increases adipogenesis, causes cholesterol accumulation in macrophages, and contributes to the development of glucose intolerance. Chemerin induces angiogenesis, which promotes the expansion of AT. This review aims to discuss the role of adipokines and myokines in the pathogenesis of the different obesity phenotypes.

Transcranial Direct Current Stimulation (tDCS) Promotes state-dependent Effects on Neuroinflammatory and Behavioral Parameters in rats Chronically Exposed to Stress and a Hyper-Palatable Diet

Chronic stress is a common condition affecting health, often associated with unhealthy eating habits. Transcranial direct current stimulation (tDCS) has been proposed to address these issues. Thus, this research investigated the effects of tDCS on biometric, behavioral, and neurochemical parameters in chronically stressed rats fed a hyper-palatable cafeteria diet (CAFD). The study lasted 8 weeks, with CAFD exposure and/or chronic restraint stress model (CRS - 1 h/day, 5 days/week, for 7 weeks) started concurrently. tDCS or sham sessions were applied between days 42 and 49 (0.5 mA, 20 min/day). CAFD increased body weight, caloric consumption, adiposity, and liver weight. It also altered central parameters, reducing anxiety and cortical levels of IL-10 and BDNF. In turn, the CRS resulted in increased adrenals in rats with standard diet (SD), and anxiety-like and anhedonic behaviors in rats with CAFD. tDCS provided neurochemical shifts in CAFD-fed stressed rats increasing central levels of TNF-α and IL-10, while in stressed rats SD-fed induced a decrease in the adrenals weight, relative visceral adiposity, and serum NPY levels. These data demonstrated the anxiolytic effect of CAFD and anxiogenic effect of stress in CAFD-fed animals. In addition, tDCS promoted state-dependent effects on neuroinflammatory and behavioral parameters in rats chronically exposed to stress and a hyper-palatable diet. These findings provide primary evidence for additional mechanistic and preclinical studies of the tDCS technique for stress-related eating disorders, envisioning clinical applicability.

Omics biomarkers and an approach for their practical implementation to delineate health status for personalized nutrition strategies

Personalized nutrition (PN) has gained much attention as a tool for empowerment of consumers to promote changes in dietary behavior, optimizing health status and preventing diet related diseases. Generalized implementation of PN faces different obstacles, one of the most relevant being metabolic characterization of the individual. Although omics technologies allow for assessment the dynamics of metabolism with unprecedented detail, its translatability as affordable and simple PN protocols is still difficult due to the complexity of metabolic regulation and to different technical and economical constrains. In this work, we propose a conceptual framework that considers the dysregulation of a few overarching processes, namely Carbohydrate metabolism, lipid metabolism, inflammation, oxidative stress and microbiota-derived metabolites, as the basis of the onset of several non-communicable diseases. These processes can be assessed and characterized by specific sets of proteomic, metabolomic and genetic markers that minimize operational constrains and maximize the information obtained at the individual level. Current machine learning and data analysis methodologies allow the development of algorithms to integrate omics and genetic markers. Reduction of dimensionality of variables facilitates the implementation of omics and genetic information in digital tools. This framework is exemplified by presenting the EU-Funded project PREVENTOMICS as a use case.

The Association between Brain-Derived Neurotrophic Factor (BDNF) Protein Level and Body Mass Index

Background and Objectives: Obesity is a major health concern worldwide. Many studies emphasize the important role of brain-derived neurotrophic factor (BDNF) in regulating appetite and body weight. We aimed to investigate the association between BDNF protein serum levels and body mass index (BMI). Materials and Methods: We conducted a cross-sectional study among 108 healthy adult participants divided into six categories depending on their body mass index (BMI). The ages of the participants ranged between 21 to 45 years. The BDNF serum level was measured using the enzyme-linked immunosorbent assay (ELISA) technique. Results: A Kruskal−Wallis test showed a significant difference in BDNF between the different BMI categories, χ2(2) = 24.201, p < 0.001. Our data also showed that BDNF levels were significantly lower in people with obesity classes II and III than those of normal weight (p < 0.05). The Spearman rank correlation test was statistically significant with negative correlations between the BMI and BDNF (r) = −0.478, (p < 0.01). Moreover, we observed a negative dose-dependent relationship pattern between BMI categories and the levels of circulating BDNF protein. Conclusions: In this study, our data support the hypothesis that low serum levels of BDNF are associated with high BMI and obesity in Saudi adults.

Metabolic homeostasis via BDNF and its receptors

Metabolic disorders result from dysregulation of central nervous system and peripheral metabolic energy homeostatic pathways. To maintain normal energy balance, neural circuits must integrate feedforward and feedback signals from the internal metabolic environment to orchestrate proper food intake and energy expenditure. These signals include conserved meal and adipocyte cues such as glucose and leptin, respectively, in addition to more novel players including brain-derived neurotrophic factor (BDNF). In particular, BDNF's two receptors, tropomyosin related kinase B (TrkB) and p75 neurotrophin receptor (p75NTR), are increasingly appreciated to be involved in whole body energy homeostasis. At times, these two receptors even seem to functionally oppose one another's actions, providing the framework for a potential neurotrophin mediated energy regulatory axis, which we explore further here.