The Effects of High-fat-diet Combined with Chronic Unpredictable Mild Stress on Depression-like Behavior and Leptin/LepRb in Male Rats

Neuroprotective effect of niacin in a rat model of obesity induced by high-fat-rich diet

This study investigates the impact of a high-fat-rich diet (HFRD) on behavioral, biochemical, neurochemical, and histopathological studies using the hypothalamus of rats following niacin (NCN) administration. The rats were divided into HFRD and normal diet (ND)-fed groups and administered selected doses of NCN, i.e., 25 mg/mL/kg (low dose) and 50 mg/mL/kg (high dose), for 8 weeks. The grouping of male rats (n = 8) was as follows: (i) Vehicle (Veh) + ND; (ii) ND + NCN (low dose); (iii) ND + NCN (high dose); (iv) Veh + HFRD; (v) HFRD + NCN (low dose); and (vi) HFRD + NCN (high dose). Behavioral tests assessed depression-like symptoms and spatial memory; after that, the hypothalamus was isolated for various analyses of sacrificed animals. NCN at both doses decreased food intake and growth rate in both diet groups and demonstrated antidepressant and memory-enhancing effects. HFRD-induced oxido-neuroinflammation decreased with both doses of NCN. HFRD-induced decreases in serotonergic neurotransmission, 5-HT1A receptor expression, and morphological alterations in the rat's hypothalamus were normalized by both doses of NCN. In conclusion, NCN, as a potential antioxidant and neuromodulator, can normalize feeding behavior and produce antidepressant and memory-improving effects in a rat model of obesity following HFRD intake.

Sex-specific associations between body composition and depression among U.S. adults: a cross-sectional study

BACKGROUND

Depression presents sexual dimorphism, and one important factor that increases the frequency of depression and contributes to sex-specific variations in its presentation is obesity. The conventional use of Body Mass Index (BMI) as an indicator of obesity is inherently limited due to its inability to distinguish between fat and lean mass, which limits its predictive utility for depression risk. Implementation of dual-energy X-ray absorptiometry (DXA) investigated sex-specific associations between body composition (fat mass, appendicular lean mass) and depression.

METHODS

Data from the NHANES cycles between 2011 and 2018 were analyzed, including 3,637 participants (1,788 males and 1,849 females). Four body composition profiles were identified in the subjects: low adiposity-low muscle (LA-LM), low adiposity-high muscle (LA-HM), high adiposity-low muscle (HA-LM) and high adiposity-high muscle (HA-HM). After accounting for confounding variables, the associations between fat mass index (FMI), appendicular skeletal muscle mass index (ASMI), body fat percentage (BFP), body composition phenotypes, and depression risk were assessed using restricted cubic spline (RCS) curves and multivariable logistic regression models. We further conducted interaction analyses for ASMI and FMI in females.

RESULTS

RCS curves indicated a U-shaped relationship between ASMI and the risk of depression in males. Logistic regression analysis revealed that in males, the second (OR = 0.43, 95%CI:0.22-0.85) and third (OR = 0.35, 95%CI:0.14-0.86) quartile levels of ASMI were significantly negatively associated with depression risk. In females, increases in BFP (OR = 1.06, 95%CI:1.03-1.09) and FMI (OR = 1.08, 95% CI:1.04-1.12) were significantly associated with an increased risk of depression. Additionally, compared to females with a low-fat high-muscle phenotype, those with LA-LM (OR = 3.97, 95%CI:2.16-7.30), HA-LM (OR = 5.40, 95%CI:2.34-12.46), and HA-HM (OR = 6.36, 95%CI:3.26-12.37) phenotypes were more likely to develop depression. Interestingly, further interaction analysis of ASMI and FMI in females revealed an interplay between height-adjusted fat mass and muscle mass (OR = 4.67, 95%CI: 2.04-10.71).

CONCLUSION

The findings demonstrate how important it is to consider body composition when estimating the risk of depression, particularly in females. There is a substantial correlation between the LA-LM, HA-LM, and HA-HM phenotypes in females with a higher prevalence of depression. It is advised to use a preventative approach that involves gaining muscle mass and losing fat.

Risk factors for depression in China based on machine learning algorithms: A cross-sectional survey of 264,557 non-manual workers

BACKGROUND

Factors related to depression differ depending on the population studied, and studies focusing on the population of non-manual workers are lacking. Thus, we aimed to identify the risk factors related to depression in non-manual workers in China.

METHOD

A large-scale cross-sectional survey was conducted between January 1, 2015 and December 31, 2020, which included 264,557 non-manual workers from one large physical examination institution in China. The Patient Health Questionnaire (PHQ-2) was used to measure depression. A total of 73 variables covering aspects of sociodemographic characteristics, general examination data, health history, symptoms, eating habits, work situation, general sleep conditions and laboratory findings were included in the collection and analysis. Machine learning algorithms of neural networks and logistic regressions were used to assess the risk of depression and explore its factors.

RESULTS

Age, feeling fatigue, sleep quality, overeating, waist-to-hip ratio (WHR), and high-density lipoprotein cholesterol (HDLC) were found to be factors of depression. Two prediction models for depression among Chinese non-manual workers were developed with good AUC (0.820), accuracy (0.943), sensitivity (0.743-0.773), and specificity (0.700-0.729).

LIMITATIONS

Data were collected at one time point only, meaning that this study cannot explain the causality of the factor on depression.

CONCLUSIONS

Our finding that age, feeling fatigue, sleep quality, overeating, WHR, and HDL-C were risk factors for depression in non-manual workers may provide strong evidence for health care facilities to develop preventive measures or government policies for non-manual workers.

The Possible Neuroprotective Effect of Caffeic Acid on Cognitive Changes and Anxiety-Like Behavior Occurring in Young Rats Fed on High-Fat Diet and Exposed to Chronic Stress: Role of β-Catenin/GSK-3B Pathway

Lifestyle influences physical and cognitive development during the period of adolescence greatly. The most important of these lifestyle factors are diet and stress. Therefore, the aim of this study was to investigate the impact of high fat diet (HFD) and chronic mild stress on cognitive function and anxiety-like behaviors in young rats and to study the role of caffeic acid as a potential treatment for anxiety and cognitive dysfunction. Forty rats were assigned into 4 groups: control, HFD, HFD + stress, and caffeic acid-treated group. Rats were sacrificed after neurobehavioral testing. We detected memory impairment and anxiety-like behavior in rats which were more exaggerated in stressed rats. Alongside the behavioral changes, there were biochemical and histological changes. HFD and/or stress decreased hippocampal brain-derived neurotrophic factor (BDNF) levels and induced oxidative and inflammatory changes in the hippocampus. In addition, they suppressed Wnt/β-catenin pathway which was associated with activation of glycogen synthase kinase 3β (GSK3β). HFD and stress increased arginase 1 and inducible nitric oxide synthase (iNOS) levels as well. These disturbances were found to be aggravated in stressed rats than HFD group. However, caffeic acid was able to reverse these deteriorations leading to memory improvement and ameliorating anxiety-like behavior. So, the current study highlights an important neuroprotective role for caffeic acid that may guard against induction of cognitive dysfunction and anxiety disorders in adolescents who are exposed to HFD and/or stress.

The Effects of Chronic Unpredictable Mild Stress and Semi-Pure Diets on the Brain, Gut and Adrenal Medulla in C57BL6 Mice

Chronic stress is known to perturb serotonergic regulation in the brain, leading to mood, learning and memory impairments and increasing the risk of developing mood disorders. The influence of the gut microbiota on serotonergic regulation in the brain has received increased attention recently, justifying the investigation of the role of diet on the gut and the brain in mood disorders. Here, using a 4-week chronic unpredictable mild stress (CUMS) model in mice, we aimed to investigate the effects of a high-fat high-glycaemic index (HFD) and high-fibre fruit & vegetable "superfood" (SUP) modifications of a semi-pure AIN93M diet on behaviour, serotonin synthesis and metabolism pathway regulation in the brain and the gut, as well as the gut microbiota and the peripheral adrenal medullary system. CUMS induced anxiety-like behaviour, dysregulated the tryptophan and serotonin metabolic pathways in the hippocampus, prefrontal cortex, and colon, and altered the composition of the gut microbiota. CUMS reduced the catecholamine synthetic capacity of the adrenal glands. Differential effects were found in these parameters in the HFD and SUP diet. Thus, dietary modifications may profoundly affect the multiple dynamic systems involved in mood disorders.

Prevalence and risk factors of thyroid dysfunction in outpatients with overweight or obese first-episode and drug-naïve major depressive disorder

BACKGROUND

Thyroid dysfunction is common in patients with major depressive disorder (MDD). However, few studies have examined risk factors for thyroid dysfunction in overweight or obese first-episode and drug-naïve (FEDN) MDD patients. This study aimed to investigate the prevalence and risk factors of thyroid dysfunction in FEDN MDD patients with comorbid high body mass index (BMI).

METHODS

A total of 1718 FEDN MDD patients were included. Hamilton Depression Rating Scale (HAMD), Hamilton Anxiety Rating Scale (HAMA), and Positive and Negative Syndrome Scale (PANSS) positive subscale were used to assess the clinical symptoms of the patients. In addition, metabolic parameters and thyroid hormone levels were measured.

RESULTS

The prevalence of thyroid dysfunction was approximately 1.75 times higher in MDD patients with comorbid overweight or obesity (72.3 %) than in patients without high BMI (58.8 %). The HAMD score, HAMA score, systolic blood pressure (BP), fasting blood glucose (FBG), thyroid peroxidase antibody (TPOAb), total cholesterol (TC), high-density lipoprotein (HDL-C), and low-density lipoprotein (LDL-C), were risk factors for thyroid dysfunction in MDD patients with high BMI. The combination of HAMD, FBG, TC, LDL-C, and systolic BP had a high AUC value of 0.76 differentiating patients with and without thyroid dysfunction.

LIMITATION

Causality cannot be drawn due to cross-sectional design.

CONCLUSIONS

This study demonstrated a high prevalence of thyroid dysfunction in FEDN MDD patients with high BMI. Severity of depression and anxiety, levels of systolic BP, FBG, TPOAb, TC, HDL-C and LDL-C appear to be associated with thyroid dysfunction in FEDN MDD patients with high BMI.

The Role of Adipokines in Health and Disease

Adipokines are cell-signaling proteins secreted by adipose tissue that has been related to a low-grade state of inflammation and different pathologies. The present review aims to analyze the role of adipokines in health and disease in order to understand the important functions and effects of these cytokines. For this aim, the present review delves into the type of adipocytes and the cytokines produced, as well as their functions; the relations of adipokines in inflammation and different diseases such as cardiovascular, atherosclerosis, mental diseases, metabolic disorders, cancer, and eating behaviors; and finally, the role of microbiota, nutrition, and physical activity in adipokines is discussed. This information would allow for a better understanding of these important cytokines and their effects on body organisms.

Appropriate Macronutrients or Mineral Elements Are Beneficial to Improve Depression and Reduce the Risk of Depression

Depression is a common mental disorder that seriously affects the quality of life and leads to an increasing global suicide rate. Macro, micro, and trace elements are the main components that maintain normal physiological functions of the brain. Depression is manifested in abnormal brain functions, which are considered to be tightly related to the imbalance of elements. Elements associated with depression include glucose, fatty acids, amino acids, and mineral elements such as lithium, zinc, magnesium, copper, iron, and selenium. To explore the relationship between these elements and depression, the main literature in the last decade was mainly searched and summarized on PubMed, Google Scholar, Scopus, Web of Science, and other electronic databases with the keywords "depression, sugar, fat, protein, lithium, zinc, magnesium, copper, iron, and selenium". These elements aggravate or alleviate depression by regulating a series of physiological processes, including the transmission of neural signals, inflammation, oxidative stress, neurogenesis, and synaptic plasticity, which thus affect the expression or activity of physiological components such as neurotransmitters, neurotrophic factors, receptors, cytokines, and ion-binding proteins in the body. For example, excessive fat intake can lead to depression, with possible mechanisms including inflammation, increased oxidative stress, reduced synaptic plasticity, and decreased expression of 5-Hydroxytryptamine (5-HT), Brain Derived Neurotrophic Factor (BDNF), Postsynaptic density protein 95(PSD-95), etc. Supplementing mineral elements, such as selenium, zinc, magnesium, or lithium as a psychotropic medication is mostly used as an auxiliary method to improve depression with other antidepressants. In general, appropriate nutritional elements are essential to treat depression and prevent the risk of depression.

Administration Time and Dietary Patterns Modified the Effect of Inulin on CUMS-Induced Anxiety and Depression

SCOPE

Prebiotics exert anxiolytic and antidepressant effects through the microbiota-gut-brain axis in animal models. However, the influence of prebiotic administration time and dietary pattern on stress-induced anxiety and depression is unclear. In this study, whether administration time can modify the effect of inulin on mental disorders within normal and high-fat diets are investigated.

METHODS AND RESULTS

Mice subjected to chronic unpredicted mild stress (CUMS) are administered with inulin in the morning (7:30-8:00 am) or evening (7:30-8:00 pm) for 12 weeks. Behavior, intestinal microbiome, cecal short-chain fatty acids, neuroinflammatory responses, and neurotransmitters are measured. A high-fat diet aggravated neuroinflammation and is more likely to induce anxiety and depression-like behavior (p < 0.05). Morning inulin treatment improves the exploratory behavior and sucrose preference better (p < 0.05). Both inulin treatments decrease the neuroinflammatory response (p < 0.05), with a more evident trend for the evening administration. Furthermore, morning administration tends to affect the brain-derived neurotrophic factor and neurotransmitters.

CONCLUSION

Administration time and dietary patterns seem to modify the effect of inulin on anxiety and depression. These results provide a basis for assessing the interaction of administration time and dietary patterns, providing guidance for the precise regulation of dietary prebiotics in neuropsychiatric disorders.

Ghrelin alleviates depression-like behaviour in rats subjected to high-fat diet and diurnal rhythm disturbance

OBJECTIVES

In the era of globalization, a sedentary lifestyle is highly linked with obesity and neurobehavioral complications such as depression. While depression is associated with dopamine dysfunction in the ventral tegmental area (VTA), ghrelin enhances the dopaminergic activity in the VTA. Therefore, the present study aimed to assess the effect of ghrelin on depression-like behaviour in rats subjected to a high-fat diet (HFD) and disturbed diurnal rhythm (DDR) for 45 days.

METHODS

The neurobehavioral deficits resulting from HFD and DDR in rats, and the behaviour modulation by intra-VTA administration of ghrelin, alone or in combination with ghrelin receptor antagonist were confirmed by evaluation of behavioural parameters in the elevated plus-maze, forced swim test, open field test, and rotarod assessment. Further, the levels of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and IL-6, oxidative stress marker malondialdehyde (MDA), and antioxidants enzymes like superoxide dismutase (SOD), reduced glutathione (GSH), and catalase (CAT) were measured.

RESULTS

The levels of TNF-α, IL-1β, IL-6, and MDA were increased in the brain of HFD and DDR exposed rats, while that of SOD, GSH, and CAT were reduced. Intra-VTA ghrelin administration from day 41-45 to the HFD and DDR exposed rats improved cognitive behaviour and physical activity confirming the antidepressant effect. Moreover, ghrelin restored the levels of SOD, GSH and CAT efficiently, and reduced that of MDA, TNF-α, IL-1β and IL-6, which signifies its protective effect.

CONCLUSION

Overall, this study confirmed the ameliorative effect of ghrelin in HFD- and DDR-induced depression-like behaviour.

Paeoniflorin Ameliorates Colonic Fibrosis in Rats with Postinfectious Irritable Bowel Syndrome by Inhibiting the Leptin/LepRb Pathway

Postinfectious irritable bowel syndrome (PI-IBS) is a highly prevalent gastrointestinal disorder associated with immune dysregulation and depression- and anxiety-like behaviors. Through traditional medicine, the active ingredient of Paeoniae Radix called paeoniflorin (PF) was previously found to prevent the symptoms of PI-IBS. However, there is limited information on the effects of PF on intestinal function and depression- and anxiety-like symptoms in PI-IBS animal models. Here, we aimed to determine the effects of PF treatment on the symptoms of PI-IBS in a rat model. The PI-IBS rat model was established via early postnatal sibling deprivation (EPSD), trinitrobenzenesulfonic acid (TNBS), and chronic unpredictable mild stress (CUMS) stimulation and then treated with different dosages of PF (10, 20, and 40 mg/kg) and leptin (1 and 10 mg/kg). The fecal water content and body weight were measured to evaluate the intestinal function, while the two-bottle test for sucrose intake, open field test (OFT), and elevated plus maze test (EMT) were performed to assess behavioral changes. The serum leptin levels were also measured using an enzyme-linked immunosorbent assay. Furthermore, the expressions of leptin and its receptor, LepRb, were detected in colonic mucosal tissues through an immunohistochemical assay. The activation of the PI3K/AKT signaling pathway and the expression of brain-derived neurotrophic factor (BDNF) were also detected via western blotting. After the experimental period, the PI-IBS rats presented decreased body weight and increased fecal water content, which coincided with elevated leptin levels and heightened depression- and anxiety-like behaviors (e.g., low sucrose intake, less frequency in the center areas during OFT, and fewer activities in the open arms during EMT). However, the PF treatment ameliorated these observed symptoms. Furthermore, PF not only inhibited leptin/LepRb expression but also reduced the PI3K/AKT phosphorylation and BDNF expression in PI-IBS rats. Notably, cotreatment with leptin (10 mg/kg) reduced the effects of PF (20 mg/kg) on colonic fibrosis, leptin/LepRb expression, and PI3K/AKT activation. Therefore, our findings suggest that leptin is targeted by PF via the leptin/LepRb pathway, consequently ameliorating the symptoms of PI-IBS. Our study also contributes novel insights for elucidating the pharmacological action of PF on gastrointestinal disorders and may be used for the clinical treatment of PI-IBS in the future.

Dietary Grape Seed Proanthocyanidin Alleviates the Liver Injury Induced by Long-Term High-Fat Diets in Sprague Dawley Rats

In mammals, the liver is the most important organ that plays a vital function in lipid metabolism. Grape seed proanthocyanidin (GSPE) is a kind of natural polyphenolic compound primarily obtained from grape skin and seeds. Recent research found it had high bioavailability in defending against obesity, hyperlipidemia, inflammatory, oxidative stress, and targeting liver tissue. However, the mechanism of GSPE in regulating obesity induced by dietary high-fat (HF) was not fully understood, particularly the influences on liver functions. Therefore, this study aimed to investigate the effects of GSPE supplementation on the liver function and lipid metabolic parameters in rats fed HF diets long-term. A total of 40 healthy female Sprague Dawley rats were selected. After 8 weeks of obesity model feeding, the rats were randomly divided into four treatments: NC, standard diet; NC + GSPE, standard diet + 500 mg/kg body weight GSPE; HF, high-fat diet; HG + GSPE, high fat diet + 500 mg/kg body weight GSPE. Results indicated that long-term HF feeding caused severe liver problems including megalohepatia, steatosis, inflammation, and hepatocyte apoptosis. The supplementation of GSPE alleviated these symptoms. The results of the current experiment confirmed that GSPE addition up-regulated the expression of the Wnt3a/β-catenin signaling pathway, thereby restraining the liver cell endoplasmic reticulum stress and hepatocyte apoptosis. Furthermore, the microRNA-103 may play a role in this signal-regulated pathway. In summary, GSPE had a protective effect on the liver and the current experiment provided a reference for the application of GSPE in animal nutrition as a kind of natural feed additive.

Association between dietary behaviors and depression in adolescent girls

Background

The growing prevalence of depression has become a major public health problem. There is limited evidence regarding the relationship between dietary behaviors and depression. The present study was designed to evaluate the association between dietary behaviors and depression score.

Methods

A total of 933 Iranian adolescent girls aged 12 to 18 years were included in this cross-sectional study. Depression severity score was assessed using a validated Persian version of Beck’s depression inventory. Dietary behaviors were pre-defined and assessed in ten domains using a standard questionnaire. To investigate the association between dietary behaviors and depression score, the linear regression analysis in crude and adjusted models was used.

Results

67.7% of participants had no or minimal depression symptoms and 32.3% of participants were categorized with mild-to-severe depression symptoms. There were significant inverse relationships between main meal consumption (Beta: -0.141; 95% CI: − 3.644 to − 1.000; P = 0.001), snack consumption (Beta: -0.100; 95% CI: − 2.400 to − 0.317; P = 0.002), regular meal consumption (Beta: 0.23; 95% CI: 0.13–0.42; P = 0.001) and food chewing (Beta: -0.152; 95% CI: − 2.279 to − 0.753; P = 0.03) with depression score. These associations remained significant after adjustment for confounding variables. In addition, frequency of intra-meal fluid intake (Beta: 0.096; 95% CI: 0.288 to 1.535; P = 0.004) and spicy foods consumption (Beta: 0.076; 95% CI: 0.098 to 1.508; P = 0.02) were directly associated with depression score in the crude model. These significant relations were disappeared in full adjusted model. No significant association was found between breakfast consumption, intake of fried foods, chewing ability, and tooth loss with depression score (P > 0.05).

Conclusions

Significant associations were observed between specific eating behaviors with depression score. Prospective studies are needed to confirm these findings.

High-Fat Diet and Short-Term Unpredictable Stress Increase Long-Chain Ceramides Without Enhancing Behavioral Despair

Clinical and preclinical studies suggest that increases in long-chain ceramides in blood may contribute to the development of depressive-like behavior. However, which factors contribute to these increases and whether the increases are sufficient to induce depressive-like behaviors is unclear. To begin to address this issue, we examined the effects of high fat diet (HFD) and short-term unpredictable (STU) stress on long-chain ceramides in the serum of male and female rats. We found that brief exposure to HFD or unpredictable stress was sufficient to induce selective increases in the serum concentrations of long-chain ceramides, associated with depression in people. Furthermore, combined exposure to HFD and unpredictable stress caused a synergistic increase in C16:0, C16:1, and C18:0 ceramides in both sexes and C18:1 and C24:1 in males. However, the increased peripheral long-chain ceramides were not associated with increases in depressive-like behaviors suggesting that increases in serum long-chain ceramides may not be associated with the development of depressive-like behaviors in rodents.

Molecular mechanisms linking stress and insulin resistance

To date, there is ample evidence to support the strong relationship between stress and insulin resistance. While diabetes mellitus acts as a potent stress inducer, stress may be an upstream event for insulin resistance as well. It is widely recognized that diabetes mellitus is more prevalent among people who have a stressful lifestyle; however, the underlying mechanisms are not well understood. In the current study, we surveyed the scientific literature for possible interactions between stress and insulin resistance and found that stress can impair glucose homeostasis, working through at least six molecular pathways.

Effects of High-fat Diet and Chronic Mild Stress on Depression-like Behaviors and Levels of Inflammatory Cytokines in the Hippocampus and Prefrontal Cortex of Rats

Obesity and depression tend to co-occur, and obese patients with chronic low-grade inflammation have a higher risk of developing depression. However, mechanisms explaining these connections have not been fully elucidated. Here, an animal model of comorbid obesity and depression induced by high-fat diet (HFD) combined with chronic unpredictable mild stress (CUMS) was used, and sucrose preference, open field, elevated plus maze and Morris water maze tests were used to detected depression-and anxiety-like behaviors and spatial memory. The levels of inflammatory cytokines and NF-κB and microglial activation in the hippocampus and prefrontal cortex were examined in the study. Our results revealed that the comorbidity group exhibited the most severe depression-like behavior. Obesity but unstressed rats had the highest serum lipid levels among groups. The HFD and CUMS alone and combination of them increased levels of IL-1β, IL-6 and TNF-α in the hippocampus and prefrontal cortex, which was significantly related to depression-like behaviors. Further, NF-κB protein and mRNA levels and microglial activation in the hippocampus and prefrontal cortex significantly increased in stressed, obese and comorbid groups, with animals in comorbid group having the highest NF-κB mRNA levels in the hippocampus and level of NF-κB proteins in the prefrontal cortex, and the highest microglial activation in both brain areas. The study concluded that HFD and CUMS alone and combination induce depression-like symptoms, abnormal serum lipid levels, microglial activation and increased inflammatory cytokines in the brain, effects that are possibly mediated by TLR4-NF-κB signaling.

Irisin Improves High-Fat Diet-Induced Sexual Dysfunction in Obese Male Rats

INTRODUCTION

Obesity is known to cause sexual dysfunction including erectile dysfunction and poor semen quality. Lifestyle modifications such as exercise have increasingly been more recognized to lower the likelihood of having sexual dysfunction or infertility in obese men. In this context, as an exercise-mimetic hormone, irisin has a potential to improve obesity-related reproductive dysfunctions. We aimed to elucidate possible effects of irisin on high-fat diet (HFD)-induced reproductive dysfunction in obese male rats.

METHODS

Rats were divided into four groups: vehicle, irisin, obese, and obese + irisin. The rats in obese and obese+irisin groups were fed with HFD (60% kcal fat) pellets for 12 weeks to induce obesity, and then obesity-induced sexual dysfunction was confirmed by the sexual behavior test (SBT). Irisin and obese+irisin groups received irisin (100 ng/kg/day) infusion by an s.c. osmotic minipump for 4 weeks after HFD-induced obesity was formed.

RESULTS

Irisin did improve a number of measures of copulation, including penile erection, ejaculation, and sexual performance, and also improved sperm morphology and motility and decreased fat-induced testicular damage. It decreased serum leptin levels. On the other hand, irisin did not affect serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone. It also increased gene expression of tyrosine hydroxylase (TH) and adrenoceptor alpha 1A (ADRA1A) in the medial preoptic area (mPOA) and nucleus accumbens (NAc).

CONCLUSION

Irisin provided a marked enhancement of HFD-induced decrease in libido, potency, sexual performance, and erection in SBT. Taken together, our results emphasize that irisin has a restorative and improver role in HFD-induced reproductive dysfunctions in obese male rats.

High-fat diet induces depression-like phenotype via astrocyte-mediated hyperactivation of ventral hippocampal glutamatergic afferents to the nucleus accumbens

Comorbidity exists between metabolic disorders and depressive syndrome with unclear mechanisms. To characterize the causal relationship, we adopted a 12-week high-fat diet (HFD) to induce metabolic disorder and depressive phenotypes in mice. Initially, we identified an enhanced glutamatergic input in the nucleus accumbens of HFD mice. Retrograde tracing and chemogenetic inhibition showed that the hyperactive ventral hippocampal glutamatergic afferents to the nucleus accumbens determined the exhibition of depression-like behavior in HFD mice. Using lentiviral knockdown and overexpression approaches, we proved that HFD-induced downregulation of glial glutamate transporters, GLAST and GLT-1, contributed to the observed circuit maladaptations and subsequent depression-like behaviors. Finally, we identified a potential therapeutic agent, riluzole, which could mitigate the HFD-induced behavioral deficits by normalizing the expressions of GLAST and GLT-1 and ventral hippocampal glutamatergic afferents to the nucleus accumbens. Overall, astrocyte-mediated disturbance in glutamatergic transmission underlies the metabolic disorder-related depressive syndrome and represents a therapeutic target for this subtype of depressive mood disorders.

Combatting Sedentary Behaviors by Delivering Remote Physical Exercise in Children and Adolescents with Obesity in the COVID-19 Era: A Narrative Review

The coexistence of childhood obesity (or its risk) and COVID-19 pandemic put children and adolescents in greater risk to develop respiratory and cardiovascular diseases. In fact, the restrictions introduced to limit the spread of the virus had detrimental effects on various lifestyle components, especially in young population. This resulted in augmented levels of physical inactivity and sedentary behaviors and a reduced time spent in play outdoors or sport practices. Contrariwise, the increased use of technology led clinicians, teachers, and trainers to maintain relations with obese children/adolescents so as to reduce sedentary behaviors and the associated health risks. This narrative review aims to describe the role of Telehealth and Tele-exercise as useful tools in the management of pediatric obesity during COVID-19 pandemic. Telehealth and Tele-exercise were effective in promoting self-monitoring and behavioral changes, including adherence to exercise training programs in children and adolescents. Moreover, tele-exercise platforms such as applications or exergames allowed flexible scheduling, limiting the infection risks.

The Type of Fat in the Diet Influences Regulatory Aminopeptidases of the Renin-Angiotensin System and Stress in the Hypothalamic-Pituitary-Adrenal Axis in Adult Wistar Rats

(1) Background: Prolonged feeding with a high-fat diet (HFD) acts as a stressor by activating the functions of the hypothalamic-pituitary-adrenal gland (HPA) stress axis, accompanied of hypertension by inducing the renin-angiotensin-aldosterone system. Angiotensinases enzymes are regulatory aminopeptidases of angiotensin metabolism, which together with the dipeptidyl peptidase IV (DPP-IV), pyroglutamyl- and tyrosyl-aminopeptidase (pGluAP, TyrAP), participate in cognitive, stress, metabolic and cardiovascular functions. These functions appear to be modulated by the type of fat used in the diet. (2) Methods: To analyze a possible coordinated response of aminopeptidases, their activities were simultaneously determined in the hypothalamus, adenohypophysis and adrenal gland of adult male rats fed diets enriched with monounsaturated (standard diet (S diet) supplemented with 20% virgin olive oil; VOO diet) or saturated fatty acids (diet S supplemented with 20% butter and 0.1% cholesterol; Bch diet). Aminopeptidase activities were measured by fluorimetry using 2-Naphthylamine as substrates. (3) Results: the hypothalamus did not show differences in any of the experimental diets. In the pituitary, the Bch diet stimulated the renin-angiotensin system (RAS) by increasing certain angiotensinase activities (alanyl-, arginyl- and cystinyl-aminopeptidase) with respect to the S and VOO diets. DPP-IV activity was increased with the Bch diet, and TyrAP activity decrease with the VOO diet, having both a crucial role on stress and eating behavior. In the adrenal gland, both HFDs showed an increase in angiotensinase aspartyl-aminopeptidase. The interrelation of angiotensinases activities in the tissues were depending on the type of diet. In addition, correlations were shown between angiotensinases and aminopeptidases that regulate stress and eating behavior. (4) Conclusions: Taken together, these results support that the source of fat in the diet affects several peptidases activities in the HPA axis, which could be related to alterations in RAS, stress and feeding behavior.

Leptin polymorphism rs3828942: risk for anxiety disorders?

Leptin is an anorexigenic hormone well recognized by its role in mediating energy homeostasis. Recently, leptin has been associated with psychiatric disorders and interestingly, leptin treatment has shown antidepressant and anxiolytic effects. We examined the association of leptin levels and leptin (LEP) gene rs3828942 polymorphism with anxiety disorders considering sex differences. A cross-sectional population-based study, including 1067 young adults, of whom 291 presented anxiety disorders diagnosed by the Mini International Neuropsychiatric Interview (MINI 5.0). The rs3828942 polymorphism was genotyped by real-time PCR and ELISA measured leptin levels. Leptin levels were not associated with anxiety disorders after adjusting for sex and body mass index (BMI) [ß = - 0.009 (- 0.090-0.072); p = 0.832]. The distribution of rs3828942 genotypes was not associated with anxiety disorders. However, in a sex-stratified sample, the A-allele of rs3828942 polymorphism was associated with risk for GAD in women even when adjusting for confounding variables [OR = 1.87 (1.17-2.98); p = 0.008]. In a subsample of 202 individuals with GAD and control matched by sex and BMI, results suggest an interaction between genotypes and GAD diagnosis based on leptin levels only in the male group [F (1, 54) = 6.464; p = 0.0139]. Leptin is suggested to be related with the neurobiology of anxiety disorders in a sex-dependent manner since women carrying the A-allele of LEP rs3828942 present a higher risk for GAD, while leptin levels seem to be lower in men with GAD carrying A-allele. Studies on the relationship between leptin polymorphisms and levels are scarce and, therefore, further research is necessary.

Childhood trauma, the stress response and metabolic syndrome: A focus on DNA methylation

Childhood trauma (CT) is well established as a potent risk factor for the development of mental disorders. However, the potential of adverse early experiences to exert chronic and profound effects on physical health, including aberrant metabolic phenotypes, has only been more recently explored. Among these consequences is metabolic syndrome (MetS), which is characterised by at least three of five related cardiometabolic traits: hypertension, insulin resistance/hyperglycaemia, raised triglycerides, low high-density lipoprotein and central obesity. The deleterious effects of CT on health outcomes may be partially attributable to dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, which coordinates the response to stress, and the consequent fostering of a pro-inflammatory environment. Epigenetic tags, such as DNA methylation, which are sensitive to environmental influences provide a means whereby the effects of CT can be biologically embedded and persist into adulthood to affect health and well-being. The methylome regulates the transcription of genes involved in the stress response, metabolism and inflammation. This narrative review examines the evidence for DNA methylation in CT and MetS in order to identify shared neuroendocrine and immune correlates that may mediate the increased risk of MetS following CT exposure. Our review specifically highlights differential methylation of FKBP5, the gene that encodes FK506-binding protein 51 and has pleiotropic effects on stress responding, inflammation and energy metabolism, as a central candidate to understand the molecular aetiology underlying CT-associated MetS risk.

Lipidomics reveals that acupuncture modulates the lipid metabolism and inflammatory interaction in a mouse model of depression

Depression is a serious disease that has considerable impact on lipid metabolism and inflammatory responses. Recent studies have shown that leptin, which is well known as a mediator of energy homeostasis and is a cytokine in inflammatory response, plays an important role in depression. Acupuncture is widely used to treat depression; however, the underlying mechanisms and the effect of acupuncture on depression remain poorly understood. In this study, we utilized the chronic restraint stress (CRS) induced depression model and acupuncture treatment was performed at KI10, LR8, LU8, LR4 (AP) or non-acupoint (NP). Then, lipidomics was applied to investigate the effects of acupuncture on lipid metabolism and analyze leptin signals in the brain and changes of immune markers. Acupuncture treatment at AP improved depression-like behavior in an open-field test, forced swimming test, and marble burying test. Concurrently, CRS mice treated with AP acupuncture (CRS + AP) had significantly lower levels of aspartate aminotransaminase (AST, liver injury markers) and exhibited different lipid patterns in liver lipidomic profiles. In particular, triglycerides (TGs) contributed the change of lipid patterns. Compared to the CRS mice, TGs with relatively high degrees of unsaturated fatty acids increased in the CRS + AP mice, but did not change in CRS mice treated with NP acupuncture (CRS + NP). The levels of leptin in plasma and leptin receptor positive cells in the brain (hypothalamus and hippocampus) decreased and increased, respectively, in the CRS + AP mice, while opposite patterns were exhibited in the CRS and CRS + NP mice. These results indicated that acupuncture treatment at AP attenuated leptin insensitivity in CRS mice. Additionally, expression of pro-inflammatory cytokines such as interleukin-1 beta and tumor necrosis factor-alpha were decreased in the spleen, plasma, and liver of CRS + AP mice, which was one of results of alleviation of leptin resistance. In conclusion, these results show that AP acupuncture treatment effectively alleviated the depression-like behavior, affected immune responses, and altered hepatic lipid metabolism through the attenuation of leptin insensitivity.

Psychological distress and internet-related behaviors between schoolchildren with and without overweight during the COVID-19 outbreak

OBJECTIVE

The novel coronavirus disease 2019 (COVID-19) pandemic, and its resulting social policy changes may result in psychological distress among schoolchildren with overweight. This study thus aimed to (1) compare psychological distress (including fear of COVID-19 infection, stress, anxiety, and depression), perceived weight stigma, and problematic internet-related behaviors between schoolchildren with and without overweight; (2) assess whether perceived weight stigma and problematic internet-related behaviors explained psychological distress.

METHODS

Schoolchildren (n = 1357; mean age = 10.7 years) with overweight (n = 236) and without overweight (n = 1121) completed an online survey assessing their fear of COVID-19 infection, stress, anxiety, depression, perceived weight stigma, problematic smartphone application use, problematic social media use, and problematic gaming.

RESULTS

Schoolchildren with overweight had significantly higher levels of COVID-19 infection fear, stress, depression, perceived weight stigma, and problematic social media use than those without overweight. Regression models showed that perceived weight stigma and problematic internet-related behaviors were significant predictors of psychological distress among schoolchildren with overweight.

CONCLUSION

Strategies to manage perceived weight stigma and problematic internet-related behaviors may have a positive influence on mental health among schoolchildren with overweight under health-threatening circumstances, such as the current COVID-19 pandemic.

Dietary and metabolic risk of neuropsychiatric disorders: insights from animal models

Neuropsychiatric disorders are major causes of the global burden of diseases, frequently co-occurring with multiple co-morbidities, especially obesity, type 2 diabetes mellitus, non-alcoholic fatty liver disease and its various risk factors in the metabolic syndrome. While the determining factors of neuropsychiatric disorders are complex, recent studies have shown that there is a strong link between diet, metabolic state and neuropsychiatric disorders, including anxiety and depression. There is no doubt that rodent models are of great value for preclinical research. Therefore, this article focuses on a rodent model of chronic consumption of high-fat diet (HFD), and/or the addition of a certain amount of cholesterol or sugar, meanwhile, summarising the pattern of diet that induces anxiety/depressive-like behaviour and the underlying mechanism. We highlight how dietary and metabolic risk influence neuropsychiatric behaviour in animals. Changes in dietary patterns, especially HFD, can induce anxiety- or depression-like behaviours, which may vary by diet exposure period, sex, age, species and genetic background of the animals used. Furthermore, dietary patterns significantly aggravate anxiety/depression-like behaviour in animal models of neuropsychiatric disorders. The mechanisms by which diet induces anxiety/depressive-like behaviour may involve neuroinflammation, neurotransmitters/neuromodulators, neurotrophins and the gut-brain axis. Future research should be focused on elucidating the mechanism and identifying the contribution of diet and diet-induced metabolic risk to neuropsychiatric disorders, which can form the basis for future clinical dietary intervention strategies for neuropsychiatric disorders.

Chronic Mild Unpredictable Stress and High-Fat Diet Given during Adolescence Impact Both Cognitive and Noncognitive Behaviors in Young Adult Mice

Stress and diet are intricately linked, and they often interact in a negative fashion. Increases in stress can lead to poor food choices; adolescence is a period that is often accompanied by increased levels of stress. Stress and poor dietary choices can affect learning and memory; it is important to understand their combined effects when occurring during crucial developmental periods. Here, we present evidence that chronic mild unpredictable stress (CMUS) and high-fat diet (HFD) impact both cognitive and noncognitive behaviors when assessed after four weeks of manipulation in four-week old mice. CMUS mice had increased anxiety in the open field test (OFT) (p = 0.01) and spent more time in the open arms of the elevated zero maze (EZM) (p < 0.01). HFD administration was shown to interact with CMUS to impair spatial memory in the Morris Water Maze (MWM) (p < 0.05). Stress and diet also led to disturbances in non-cognitive behaviors: CMUS led to significantly more burrowing (p < 0.05) and HFD administration led to the poorer nest construction (p < 0.05). These findings allow for researchers to assess how modifying lifestyle factors (including diet and stress) during adolescence can serve as a potential strategy to improve cognition in young adulthood.

The Role of Hypothalamic Inflammation in Diet-Induced Obesity and Its Association with Cognitive and Mood Disorders

Obesity is often associated with cognitive and mood disorders. Recent evidence suggests that obesity may cause hypothalamic inflammation. Our aim was to investigate the hypothesis that there is a causal link between obesity-induced hypothalamic inflammation and cognitive and mood disorders. Inflammation may influence hypothalamic inter-connections with regions important for cognition and mood, while it may cause dysregulation of the Hypothalamic-Pituitary-Adrenal (HPA) axis and influence monoaminergic systems. Exercise, healthy diet, and glucagon-like peptide receptor agonists, which can reduce hypothalamic inflammation in obese models, could improve the deleterious effects on cognition and mood.

Resveratrol Supplementation Attenuates Cognitive and Molecular Alterations under Maternal High-Fat Diet Intake: Epigenetic Inheritance over Generations

Environmental factors such as maternal high-fat diet (HFD) intake can increase the risk of age-related cognitive decline in adult offspring. Epigenetic mechanisms are a possible link between diet effect and neurodegeneration across generations. Here, we found a significant decrease in triglyceride levels in a high-fat diet with resveratrol (RSV) HFD + RSV group and the offspring. Firstly, we obtained better cognitive performance in HFD+RSV groups and their offspring. Molecularly, a significant increase in DNA methylation (5-mC) levels, as well as increased gene expression of DNA methyltransferase 1 (Dnmt1) and Dnmt3a in HFD + RSV F1 group, were found. Furthermore, a significant increase of N6-Methyladenosine methylation (m6A) levels in HFD+RSV F1, as well as changes in gene expression of its enzymes Methyltransferase like 3 (Mettl3) and FTO alpha-ketoglutarate dependent dioxygenase (Fto) were found. Moreover, we found a decrease in gene expression levels of pro-inflammatory markers such as Interleukin 1β (Il1-β), Interleukin 6 (Il-6), Tumor necrosis factor-α (Tnf-α), C-X-C motif chemokine ligand 10 (Cxcl-10), the pro-inflammatory factors monocyte chemoattractant protein 1 (Mcp-1) and Tumor growth factor-β1 (Tgf-β1) in HFD+RSV and HFD+RSV F1 groups. Moreover, there was increased gene expression of neurotrophins such as Neural growth factor (Ngf), Neurotrophin-3 (Nt3), and its receptors Tropomyosin receptor kinase TrkA and TrkB. Likewise, an increase in protein levels of brain-derived neurotrophic factor (BDNF) and phospho-protein kinase B (p-Akt) in HFD+RSV F1 was found. These results suggest that maternal RSV supplementation under HFD intake prevents cognitive decline in senescence-accelerated mice prone 8 (SAMP8) adult offspring, promoting a reduction in triglycerides and leptin plasma levels, changes in the pro-inflammatory profile, and restoring the epigenetic landscape as well as synaptic plasticity.

Electroacupuncture improves synaptic plasticity by regulating the 5-HT1A receptor in hippocampus of rats with chronic unpredictable mild stress

Objectives

To investigate the antidepressant effects of electroacupuncture (EA) on chronic unpredictable mild stress (CUMS) in rats, as well as the effects of EA on hippocampal neurons, synaptic morphology, and 5-hydroxytryptamine (HT) receptor expression.

Methods

Forty adult male Wistar rats were randomly divided into normal control, CUMS, EA, and paroxetine groups. CUMS modeling was performed for 21 days, followed by 14 days of intervention: rats in the EA group underwent stimulation of GV20 and GV29 acupuncture points for 30 minutes daily; rats in the paroxetine group were administered paroxetine daily. Behavioral tests, transmission electron microscopy, western blotting, and real-time quantitative polymerase chain reaction were used to evaluate the effects of the intervention.

Results

EA treatment reversed the behavioral changes observed in rats due to CUMS modeling; it also improved the pathological changes in organelles and synaptic structures of hippocampal neurons, and upregulated the protein and mRNA expression levels of 5-HT1A receptor. There were no significant differences in 5-HT1B receptor protein and mRNA expression levels among the groups.

Conclusions

EA treatment can alleviate depression-like symptoms in CUMS rats. The underlying mechanism may include promoting the expression of 5-HT1A receptor mRNA and protein, thereby improving synaptic plasticity in the hippocampus.

The impact of insulin on the serotonergic system and consequences on diabetes-associated mood disorders

The idea that insulin could influence emotional behaviours has long been suggested. However, the underlying mechanisms have yet to be solved and there is no direct and clear-cut evidence demonstrating that such action involves brain serotonergic neurones. Indeed, initial arguments in favour of the association between insulin, serotonin and mood arise from clinical or animal studies showing that impaired insulin action in type 1 or type 2 diabetes causes anxiety- and depressive symptoms along with blunted plasma and brain serotonin levels. The present review synthesises the main mechanistic hypotheses that might explain the comorbidity between diabetes and depression. It also provides a state of knowledge of the direct and indirect experimental evidence that insulin modulates brain serotonergic neurones. Finally, it highlights the literature suggesting that antidiabetic drugs present antidepressant-like effects and, conversely, that serotonergic antidepressants impact glucose homeostasis. Overall, this review provides mechanistic insights into how insulin signalling alters serotonergic neurotransmission and related behaviours bringing new targets for therapeutic options.

Effects of chronic stress on depressive-like behaviors and JMJD3 expression in the prefrontal cortex and hippocampus of C57BL/6 and ob/ob mice

BACKGROUND

Depression is a psychiatric disorder which is accompanied by neuroinflammatory responses. Obesity is considered as a low-grade inflammatory state. Studies have found that obese individuals are more likely to suffer from depression, but its possible mechanism has not been specifically illuminated. The Jumonji domain protein 3 (JMJD3) is a specific histone demethylase of trimethylation at lysine 27 of histone-H3 (H3K27me3). Over-expressions of JMJD3 induces the demethylation of H3K27me3 and results in the expression of pro-inflammatory genes, while its upregulation may be limited by adiponectin (APN). However, the role of JMJD3 in susceptibility to neuroinflammation and depression in obesity has not been clarified.

METHODS

Chronic unpredictable mild stress (CUMS) was selected to build depression model in C57BL/6 and ob/ob mice. Sucrose preference test, tail suspension test, open field test and Morris water maze test were used to detect depressive-like behaviors and memory impairment. Microglial activation, pro-inflammatory cytokines, APN, NF-ĸB, JMJD3 and H3K27me3 expressions in the serum, prefrontal cortex (PFC) and hippocampus (HIP) were examined in C57BL/6 and ob/ob mice. Meanwhile, GSK-J4 was used to inhibit JMJD3 expression.

RESULTS

CUMS led to depressive-like behaviors and memory impairment, microglial activation, increased expressions of pro-inflammatory cytokines, NF-κB and JMJD3, decreased expression of H3K27me3 in the PFC and HIP in C57BL/6 and ob/ob mice. Meanwhile, ob/ob mice showed worse behavioral injury and memory impairment, microglial excessively activation, over-expression of pro-inflammatory cytokines and NF-ĸB and decreased H3K27me3 levels than C57BL/6 mice. CUMS also decreased the APN levels in the serum and brain tissues in ob/ob mice compared to C57BL/6 mice. But GSK-J4 could relieve these alterations.

CONCLUSIONS

JMJD3 might be involved in the susceptibility to depressive-like behaviors and neuroinflammation of obese mice by the demethylation of H3K27me3, and decreased levels of APN could reduce Enhancer of zeste homolog 2 (EZH2) binding with H3K27me3. The role of JMJD3 in severer inflammatory state in the comorbidity of obesity and depression was considered.

The Relationship between Food Security Status and Sleep Disturbance among Adults: A Cross-Sectional Study in an Indonesian Population

Background: The relationship between food insecurity and the experience of sleep disturbance has received little attention among researchers, although food insecurity is associated with poor physical and mental health globally. This study aimed to investigate the relationship between food security status and sleep disturbance among adults 20–64 years old. Methods: The study’s population-based sample included 20,212 Indonesian adults who participated in the fifth wave of the Indonesia Family Life Survey (IFLS5) in 2014. Dietary intake data, gathered using a food frequency questionnaire (FFQ), were used to assess the food security status. Sleep disturbance was assessed using the 10-item Patient-Reported Outcomes Measurement Information System (PROMIS) questionnaire. We used multiple linear and logistic regression models to test the study hypothesis. Results: A higher likelihood of experiencing sleep disturbance was recorded in people aged older than 56 years (OR = 1.78, 95% CI: 1.17–2.72, p = 0.007), people with depressive symptoms (OR = 3.57, 95% CI: 2.77–4.61, p < 0.001), and food-insecure people (OR = 1.32, 95% CI: 1.02–1.70, p = 0.036). A lower likelihood of experiencing sleep disturbance was recorded in people with low educational attainment (OR = 0.41, 95% CI: 0.30–0.57, p < 0.001). Sleep disturbance was dependent on the food consumption groups and food security status among men (p = 0.004). Conclusions: Sleep disturbance may be affected by the food-insecure status of adults, and later, may lead to serious health outcomes.

Behavioral, cardiovascular and endocrine alterations induced by chronic stress in rats fed a high-fat diet

Chronic stress is a risk factor for cardiovascular diseases (CVD) and anxiety disorders (AD). Obesity also increases the risk of CVD and AD. The modern lifestyle commonly includes high-fat diet (HFD) intake and daily exposure to stressful events. However, it is not completely understood whether chronic stress exacerbates HFD-induced behavioral and physiological changes. Thus, this study aimed to evaluate the effects of the exposure to chronic variable stress (CVS) on behavioral, cardiovascular, and endocrine parameters in rats fed an HFD. Male Wistar rats were divided into four groups: control-standard chow diet (control-SD), control-HFD, CVS-SD, and CVS-HFD. The control-HFD and CVS-HFD groups were fed with HFD for six weeks. The CVS-HFD and CVS-SD groups were exposed to a CVS protocol in the last ten days of the six weeks. The behavioral analysis revealed that CVS decreased the open-arm exploration time during the elevated plus-maze test (p < 0.05). HFD promoted metabolic disorders and increased angiotensin II and leptin blood levels (p < 0.05). CVS or HFD increased blood pressure and the sympathetic nervous system (SNS) modulation of the heart and vessels and decreased baroreflex activity (p < 0.05). Combining CVS and HFD exacerbated the cardiac SNS response and increased basal heart rate (HR) (p < 0.05). CVS or HFD did not affect vascular function and aorta nitrate (p > 0.05). Taken together, these data indicate a synergism between HFD and CVS on the HR and cardiac SNS responses, suggesting an increased cardiovascular risk. Besides, neuroendocrine and anxiogenic disturbers may contribute to the cardiovascular changes induced by HFD and CVS, respectively.

Synergistic effects of low-level stress and a Western diet on metabolic homeostasis, mood, and myocardial ischemic tolerance

How low-level psychological stress and overnutrition interact in influencing cardiometabolic disease is unclear. Mechanistic overlaps suggest potential synergies; however, findings are contradictory. We test whether low-level stress and Western diet (WD) feeding synergistically influence homeostasis, mood, and myocardial ischemic tolerance. Male C57BL6/J mice were fed a control diet or WD (32%/57%/11% calories from fat/carbohydrates/protein) for 12 wk, with subgroups restrained for 30 min/day over the final 3 wk. Metabolism, behavior, tolerance of perfused hearts to ischemia-reperfusion (I/R), and cardiac “death proteins” were assessed. The WD resulted in insignificant trends toward increased body weight (+5%), glucose (+40%), insulin (+40%), triglycerides (+15%), and cholesterol (+20%) and reduced leptin (−20%) while significantly reducing insulin sensitivity [100% rise in homeostasis model assessment of insulin resistance (HOMA-IR), P < 0.05]. Restraint did not independently influence metabolism while increasing HOMA-IR a further 50% (and resulting in significant elevations in insulin and glucose to 60–90% above control) in WD mice ( P < 0.05), despite blunting weight gain in control and WD mice. Anxiogenesis with restraint or WD was nonadditive, whereas anhedonia (reduced sucrose consumption) only arose with their combination. Neuroinflammation markers (hippocampal TNF-α, Il-1b) were unchanged. Myocardial I/R tolerance was unaltered with stress or WD alone, whereas the combination worsened dysfunction and oncosis [lactate dehydrogenase (LDH) efflux]. Apoptosis (nucleosome accumulation) and death protein expression (BAK, BAX, BCL-2, RIP-1, TNF-α, cleaved caspase-3, and PARP) were unchanged. We conclude that mild, anxiogenic yet cardio-metabolically “benign” stress interacts synergistically with a WD to disrupt homeostasis, promote anhedonia (independently of neuroinflammation), and impair myocardial ischemic tolerance (independently of apoptosis and death protein levels).

High-Fat Diet Enhances Working Memory in the Y-Maze Test in Male C57BL/6J Mice with Less Anxiety in the Elevated Plus Maze Test

Obesity is characterized by massive adipose tissue accumulation and is associated with psychiatric disorders and cognitive impairment in human and animal models. However, it is unclear whether high-fat diet (HFD)-induced obesity presents a risk of psychiatric disorders and cognitive impairment. To examine this question, we conducted systematic behavioral analyses in C57BL/6J mice (male, 8-week-old) fed an HFD for 7 weeks. C57BL/6J mice fed an HFD showed significantly increased body weight, hyperlocomotion in the open-field test (OFT) and Y-maze test (YMZT), and impaired sucrose preference in the sucrose consumption test, compared to mice fed a normal diet. Neither body weight nor body weight gain was associated with any of the behavioral traits we examined. Working memory, as assessed by the YMZT, and anxiety-like behavior, as assessed by the elevated plus maze test (EPMT), were significantly correlated with mice fed an HFD, although these behavioral traits did not affect the entire group. These results suggest that HFD-induced obesity does not induce neuropsychiatric symptoms in C57BL/6J mice. Rather, HFD improved working memory in C57BL/6J mice with less anxiety, indicating that an HFD might be beneficial under limited conditions. Correlation analysis of individual traits is a useful tool to determine those conditions.

The impact of chronic stress on energy metabolism

The brain is exceptionally demanding in terms of energy metabolism. Approximately 20% of the calories consumed are devoted to our cerebral faculties, with the lion's share provided in the form of glucose. The brain's stringent energy dependency requires a high degree of harmonization between the elements responsible for supplying- and metabolizing energetic substrates. However, chronic stress may jeopardize this homeostatic energy balance by disruption of critical metabolic processes. In agreement, stress-related mental disorders have been linked with perturbations in energy metabolism. Prominent stress-induced metabolic alterations include the actions of hormones, glucose uptake and mitochondrial adjustments. Importantly, fundamental stress-responsive metabolic adjustments in humans and animal models bear a striking resemblance. Here, an overview is provided of key findings, demonstrating the pervasive impact of chronic stress on energy metabolism. Furthermore, I argue that medications, aimed primarily at restoring metabolic homeostasis, may constitute a novel approach to treat mental disorders.

Differential effect of high-fat, high-sucrose and combined high-fat/high-sucrose diets consumption on fat accumulation, serum leptin and cardiac hypertrophy in rats

The consumption of high calorie-content diets is the first cause of obesity, probably the main health issue worldwide; however, the experimental evidences for evaluating the differential metabolic modifications of high-sucrose or high-fat diets are scare. We evaluated the metabolic outcomes of the obesity induced by the chronic consumption of high-sucrose (HS), high-fat (HF) or combined diets (HSHF), among the effect on the development of cardiac hypertrophy in Wistar rats. Rats from the HS, HF, and HSHS groups developed moderate obesity. Only the HS group showed increased triglycerides levels after four months. Increased leptin levels were observed in HS and HF groups without changes on cardiac hypertrophy; on the opposing, HSHF group presented hypertrophy without the changes in serum leptin. The three experimental groups showed a decreased expression of leptin receptors ObR-b. In our results, the kind of diet for the induction of obesity is relevant for the outcome of the pathological profile.

PPARγ-mediated microglial activation phenotype is involved in depressive-like behaviors and neuroinflammation in stressed C57BL/6J and ob/ob mice

BACKGROUND

There is an increased risk for obese patients with chronic low-grade inflammation to develop depression. Stress induces microglial activation and neuroinflammation that play crucial roles in the pathogenesis of depression. Peroxisome proliferator-activated receptor gamma (PPARγ), a nuclear transcription factor, regulates microglial polarization and neuroinflammation. Our study aimed to investigate the role of PPARγ in the development of depressive symptoms and neuroinflammation induced by chronic unpredictable mild stress (CUMS) in wild-type/C57BL/6J (wt) and leptin-deficient (ob/ob) mice.

METHODS

CUMS was used to build a depression model with wt and ob/ob mice. Depressive-like behaviors were evaluated by sucrose preference test, open field test, tail suspension test, and Morris water maze test. Cytokines, the activated microglial state, and nuclear factor-κB (NF-κB) and PPARγ expression in the prefrontal cortex (PFC) and hippocampus (HIP) were examined by enzyme-linked immunosorbent assay (ELISA), immunofluorescence, and western blotting. Additionally, pioglitazone, an agonist of PPARγ, was used as a treatment intervention.

RESULTS

After CUMS, ob/ob mice exhibited severe behavioral disorders and spatial memory impairment, and higher levels of pro-inflammatory cytokines, M1/M2 ratios, and NF-κB activation, as well as lower levels of anti-inflammatory cytokines and PPARγ expression in the PFC and HIP compared to wt mice. Administration of pioglitazone relieved these alterations in wt and ob/ob mice.

CONCLUSIONS

CUMS was able to induce severe depressive-like behaviors, neuroinflammation, and reduced expression of PPARγ in ob/ob mice as compared to wt mice. This suggests that PPARγ mediates the microglial activation phenotype, which might be related to the susceptibility of stressed ob/ob mice to develop depressive disorder.

Meta-analysis of 5-hydroxytryptamine transporter gene promoter region polymorphism and post-stroke depression

OBJECTIVE

To investigate the relationship between 5-hydroxytryptamine transporter gene promoter region (5-HTTLPR) gene polymorphism and post-stroke depression (PSD).

METHODS

We searched the CNKI, China Science and Technology Journal, China WanFang, PubMed, Embase, and Web of Science databases for studies of the relationship between 5-HTTLPR polymorphism and PSD. Data were evaluated using Stata software.

RESULTS

The L allele was significantly related to the S allele (OR = 0.57, 95% confidence interval (CI) 0.49-0.65). The dominant genotype LL + LS was related to SS (OR = 0.48, 95%CI 0.39-0.59), the recessive genotype LL was related to LS + SS (OR = 0.39, 95%CI: 0.30-0.51), the homozygous genotype LL was related to SS (OR = 0.24, 95%CI 0.18-0.33), and the heterozygous genotype LS was related to SS (OR = 0.55, 95 CI 0.44-0.68). All the differences were significant. Ethnicity subgroup analysis showed significant differences among the five genotypes in both Asians and Caucasians. Hardy-Weinberg equilibrium (HWE) subgroup analysis showed that, after removal of a non-HWE-conforming control group, all five genotypes were significant and genotypes LL, LS + LL, and LS and L allele had beneficial effects on recovery from PSD.

CONCLUSION

5-HTTLPR gene polymorphism is strongly associated with PSD, and the LL, LS + LL, and LS genotypes and L allele may protect against this condition.

Reduction of depression-like behavior in rat model induced by ShRNA targeting norepinephrine transporter in locus coeruleus

Depression may be associated with reduced monoamine neurotransmission, particularly serotonin and norepinephrine (NE). Reuptake of NE by the norepinephrine transporter (NET) is the primary mechanism by which many of the antidepressants are high-affinity substrates for NET. This study aimed to examine the effect of lentivirus-mediated shRNA targeting NET in locus coeruleus (LC) on depression-like behaviors of rats. We randomly assigned 60 male Wistar rats to 6 experimental groups: (1) Control group: without chronic unpredictable mild stress (CUMS) and without NET-shRNA treatment; (2) shRNA group: without CUMS + NET-shRNA; (3) CUMS group: 3-week CUMS without NET-shRNA; (4) CUMS + nonsense shRNA group; (5) CUMS + amygdala (Amy)-shRNA group; (6) CUMS+ locus coeruleus (LC)-shRNA group. First, recombinant lentiviral vector expressing shRNA (ShRNA-629, ShRNA-330, ShRNA-1222, ShRNA-1146 or ShRNA- negative control) against NET were produced, and their efficiency in knocking down of NET in PC12 cells were assessed by Q-PCR and western blot analysis. Second, shRNA was injected into the rat LC bilaterally to investigate whether it could prevent the depressive-like behavior induced by 3-week CUMS. Third, we tested the depressive-like behavior of the rats in the forced swimming test, the open field test, the sucrose preference test, as well as the body weight gain at the end of the seventh week. Finally, the protein expressions of NET was measured by western blot and the NE levels were measured by high performance liquid chromatography. Q-PCR and western blot showed that the ShRNA-1146 had the best interference efficiency targeting on NET in PC12 cells (p < 0.01). Compared to the depression model group, the immobility time in the forced swimming test was significantly reduced (p < 0.01), but the sucrose preference and the total scores in the open field test were significantly increased (all p < 0.01) in the group treated with shRNA in LC. Furthermore, compared with the depression model group, NET levels were significantly decreased (p < 0.01), but NE levels were significantly increased in the group treated with shRNA in LC (p < 0.05). Our findings suggest that Lentivirus-mediated shRNA targeting NET in LC downregulated NET both in vitro and in vivo, resulting in a significant decrease in depressive-like behavior of rats.

Chronic exposure to paroxetine or bupropion modulates the pubertal maturation and the reproductive system in female rats

Antidepressant drugs are globally used to treat several psychiatric disorders in pediatric patients and their prescription has continued to increase in recent years, especially among girls. In addition to its well-known metabolic and gastrointestinal side effects, antidepressants can cause sexual dysfunction in adults. However, the effects of the antidepressants on puberty onset and reproductive system remain unclear in children and adolescents. Therefore, the goal of this study is to examine the effects of chronic postnatal antidepressant drugs, paroxetine or bupropion, treatments on puberty onset and reproductive system components in female rats weaned at postnatal day (PND) 21. Female rats (n = 10 for each group) were exposed to vehicle (0.2 mL of saline), paroxetine (3.6 mg/kg in 0.2 mL of saline) or bupropion (17 mg/kg in 0.2 mL of saline) daily by oral gavage from the PND 21 to PND 90-93. Chronic paroxetine or bupropion treatments advanced the puberty onset, but the difference was statistically significant in only the paroxetine group. The exposure to bupropion significantly decreased the serum anti-Müllerian hormone (AMH) levels and luteinizing hormone (LH) levels. There were increases in serum estradiol levels by both antidepressant treatments and the significance was found in only the paroxetine group. Consistent with these results, histopathologic changes were observed in the ovary and uterus tissues taken from both antidepressant-treated rats. The obtained results of chronic postnatal exposure to paroxetine or bupropion may change the timing of puberty onset and lead to disruption of reproductive functions in females.

Evaluation of Interleukin-6, Leukotriene B-4, and Nitric Oxide Levels in Exhaled Breath Condensate of Asymptomatic Obese Individuals: Are Obese Patients Under Risk of Developing Asthma?

Objective

If systemic inflammation in relation with obesity causes asthma, the detection of increased airway inflammation among obese individuals who do not have any respiratory symptoms can be also beneficial in indentifying obese patients who are at risk of developing asthma. The aim of this study was to evaluate the systemic and airway inflammation of asymptomatic obese and non-obese individuals.

Materials and Methods

Obese and non-obese individuals with no respiratory symptoms were included. Inflammatory biomarkers such as C-reactive protein (CRP), exhaled breath condensate (EBC) interleukin-6 (IL-6), EBC leukotriene B-4 (LTB-4), and EBC nitric oxide (NO) levels of obese and non-obese individuals were determined.

Results

Forty-five obese individuals (body mass index [BMI]≥30) and 31 non-obese individuals (BMI≤25) as a control group were included in this study. The mean age of the obese group (38.7±11.4 years) was significantly higher than the one of the non-obese group (29.5±8.6 years; p<0.001). There was no significant relationship between gender and BMI (χ² =1.471, p=0.225). CRP levels were significantly higher in the obese group (6.94±8.28) than the non-obese group (3.29±0.39; p<0.001). The levels of EBC IL-6 in obese and non-obese group were found as 22.61±12.53 and 21.08±14.39, respectively (p=0.624). There was no significant difference between EBC NO levels of the obese group and non-obese group (24.35±10.9 vs. 21.56±7.83; p=0.226). No significant difference was found between the EBC LTB-4 level in the obese group and the non-obese group (36.39±89.82 vs. 16.64±17.45; p=0.231).

Conclusion

Increased systemic inflammation in obese individuals who had no respiratory symptoms might indicate the tendency of asthma. However, airway inflammation was not significantly different between groups. Therefore the relationship between obesity and asthma should be investigated in future large-scale studies determining the direct effects of adipokines on airways.

Chronic sub-anesthetic ketamine induces permanent hypolocomotion and impairment of hippocampus in adolescent cynomolgus monkeys

Ketamine has gained increasing popularity in adolescent drug abusers worldwide. However, relatively little is known about the long-term effects of recreational ketamine on adolescent hippocampus. The present study investigates the effects of different periods (1, 3 and 6 months) of recreational ketamine administration on locomotor activity and neuron damage in the hippocampus of adolescent cynomolgus monkeys. 32 4-year-old male cynomolgus monkeys were divided into control, 1-month, 3-month and 6-month groups. All animals in ketamine groups received daily intravenous injection with 1 mg/kg ketamine in saline for respective 1, 3 or 6 months while control group received normal saline. Automatic behaviors were recorded for 10 min before and after ketamine and saline administration. Meanwhile, the markers of apoptosis in the hippocampus were assessed using terminal deoxynucleotidyl transferase-mediated biotinylated dUTP nick end labeling (TUNEL), electron microscopy and western blotting. Results showed that ketamine significantly decreased locomotor activity, increased apoptotic neurons and pro-apoptotic proteins, cleaved Caspase-3 and Bax, while decreased the anti-apoptotic protein Bcl-2 in the hippocampus after 6-month ketamine administration. Our study suggested that chronically recreational ketamine might induce hypolocomotion and neurotoxic effect via apoptotic pathway in adolescent hippocampus of monkeys.

Feed restriction since lactation has reduced anxiety in adult Wistar rats

ABSTRACT Objective To evaluate the effects of macronutrients (protein, carbohydrate and/or lipid) in the diet of young adult (72 days) and adult (182 days) Wistar rats treated ad libitum and with 30% restriction from birth on anxiety in the elevated plus-maze. Methods We used 238 rats treated from birth, composing the groups: Control, Protein, Carbohydrate, Lipid, Carbohydrate and Lipid, Control Restriction, Protein Restriction, Carbohydrate Restriction, Lipid Restriction and Carbohydrate and Lipid Restriction. The animals were weighed at the beginning and at the end of the experiment and tested in the elevated plus-maze. Data were submitted to analysis of variance, followed by the Newman-Keuls Test (p<0.05). Results Among the animals treated ad libitum, the Control, Carbohydrate plus Lipid and Lipid gained more weight than the Carbohydrate and Protein; ad libitum animals gained more weight than those on restriction; among the restrictions, Carbohydrate Restriction rats were the ones that gained less weight. Diet-restricted animals exhibited reduced first-entry latency, greater percentage of entries and time spent, frequency of open arm extremity visits, head dipping (protected and unprotected), and length of stay in the central area of the elevated plus-maze. The animals with 182 days presented greater latency for first entry, reduced frequency of false entries and visits to the ends of the open arms and protected head dipping. Conclusion Food restricted animals, regardless of the macronutrient present in the diet, were less anxious and/or increased their impulsivity and those at 182 days were more anxious and/or with reduced impulsivity.

A healthy diet and physical activity are important to promote healthy ageing among older Chinese people

Objective

To examine the associations between multiple health behaviours and health outcomes among older Chinese adults.

Methods

Data from the World Health Organization’s Study on global AGEing and adult health Wave 1 (2007–2010), collected among the older Chinese population, were included in this study. Smoking, diet, and physical activity were analysed by linear regression for any associations with depressive symptoms, quality of life (QoL), cognitive function, and physical function.

Results

A total of 13 367 participants aged >49 years were included in the analyses. After controlling for key socioeconomic factors, healthy diet was significantly associated with higher QoL (β = 0.099) and better cognitive function (β = 0.023). Physical activity was significantly associated with fewer depressive symptoms (β = –0.020), higher QoL (β = 0.086), better cognitive function (β = 0.072), and better physical function (β = –0.155 [higher scores = poorer physical function]). No relationship was found between smoking and any health-related outcome included in this study.

Conclusion

This study demonstrates the importance of healthy diet and physical activity for health outcomes in the older Chinese population.

Body Dissatisfaction in Adolescents: Differences by Sex, BMI and Type and Organisation of Physical Activity

The aim of this study was to assess the differences in body dissatisfaction (BD) of male and female adolescents by body max index (BMI) and the quantity, type and organisation of physical activity (PA). To do so, 652 adolescents aged 12-17 years participated in a cross-sectional study. The cognitive-affective component of BD was assessed with the Body Shape Questionnaire (BSQ) and the perceptual component with Gardner's scale for the assessment of, body image (BI). PA was measured with the International Physical Activity Questionnaire (IPAQ-SF) and the item 1 from the Physical Activity Questionnaire for Adolescents (PAQ-A). The results show that sex and BMI are key variables when determining BD. Moderate-to-vigorous PA (MVPA) was moderately associated with a greater body satisfaction in males but no association was found between BD and the participation and organisation of PA. Moreover, the results suggest that participants in aesthetic/lean PA are at a higher risk of suffering from BD than participants in other PA types. These findings provide useful information for the design of programmes promoting healthy lifestyles, weight control and BI concern during the school period.

Telephone-based cognitive behavioural therapy for female patients 1-year post-bariatric surgery: A pilot study

OBJECTIVE

Although bariatric surgery is a durable treatment for patients with severe obesity, it does not directly address behavioural and psychological factors that potentially contribute to weight regain post-surgery. Psychological interventions, such as cognitive behavioural therapy (CBT), can be challenging to access due to physical limitations and practical barriers. Telephone-based CBT (Tele-CBT) can improve eating psychopathology and psychological distress before and after surgery. Given the frequent occurrence/recurrence of problematic eating-related and psychological issues many patients face 1-year post-surgery, this open-trial pilot study aimed to evaluate the effectiveness of Tele-CBT delivered 1-year post-surgery as an adjunctive treatment to the usual standard of bariatric care.

METHODS

Patients (n=43) received six 1-h Tele-CBT sessions delivered weekly beginning at 1-year post-surgery. Patients completed questionnaire packages before and after the intervention to assess changes in binge eating (BES), emotional eating (EES), depression (PHQ-9), and anxiety (GAD-7).

RESULTS

Thirty-two patients completed Tele-CBT yielding a 74.4% completion rate. Participants reported significant improvements on the Binge Eating Scale (t(31)=3.794, p=0.001), Emotional Eating Scale (t(31)=3.508, p=0.001), Patient Health Questionnaire-9 Item Scale (z=-2.371, p=0.018), and Generalised Anxiety Disorder-7 Item Scale (z=-3.546, p<0.001) immediately following Tele-CBT.

DISCUSSION

The results demonstrate that Tele-CBT delivered 1-year post-surgery may improve binge eating, emotional eating, depression, and anxiety. Additional research is warranted to examine whether these changes translate into long-term improvements in bariatric surgery outcomes.

Pharmacological interventions targeting anhedonia in patients with major depressive disorder: A systematic review

Anhedonia is defined as a diminished ability to experience interest or pleasure, and is a critical psychopathological dimension of major depressive disorder (MDD). The purpose of the current systematic review is to evaluate the therapeutic efficacy of pharmacological treatments on measures of anhedonia in adults with MDD. Electronic databases Cochrane Library (CENTRAL), Ovid MEDLINE, PubMed, PsycINFO, and Google Scholar were searched from inception to June 1, 2018 for longitudinal studies utilizing pharmacotherapy for the treatment of anhedonia in patients with MDD. A total of 17 eligible studies were identified (i.e., evaluated the effects of pharmacotherapy on a measure of anhedonia). Among the identified studies, the efficacy of 14 different pharmacotherapies on measures of anhedonia were evaluated, including melatonergic agents (i.e. agomelatine), monoaminergic agents (i.e. moclobemide, clomipramine, bupropion, venlafaxine, fluoxetine, amitifadine and levomilnacipran, escitalopram, and sertraline), glutamatergic agents (i.e., ketamine and riluzole), stimulants (i.e., methylphenidate), and psychedelics (i.e., psilocybin). Based on the available evidence, most antidepressants demonstrated beneficial effects on measures of anhedonia as well as the other depressive symptoms. Only escitalopram/riluzole combination treatment was ineffective in treating symptoms of anhedonia in MDD. Continued research is warranted to further support the efficacy of mechanistically-distinct antidepressants in treating symptoms of anhedonia in MDD. Future research should also aim to parse out the heterogeneous effects of different pharmacotherapies on anhedonic symptoms.