Background And Aims: We investigated the effect of WAY-163909, a novel 5-hydroxytryptamine selective 2C receptor agonist on body weight, blood glucose levels, and insulin resistance in obese and diabetic Wistar rats.
Materials And Methods: We used twenty male Wistar rats with obesity and obesity-induced diabetes and twenty healthy Wistar rats as a control group. Each of these groups was separated into two subgroups: one with a daily intraperitoneal application of WAY-163909 (1 mg/kg) and one without.
Individuals with pre-diabetes are commonly overweight and benefit from dietary and physical activity strategies aimed at decreasing body weight and hyperglycemia. Early insulin resistance can be estimated the triglyceride glucose index {TyG = Ln [TG (mg/dl) × fasting plasma glucose (FPG) (mg/dl)/2]} and the hypertriglyceridemic-high waist phenotype (TyG-waist), based on TyG x waist circumference (WC) measurements. Both indices may be useful for implementing personalized metabolic management.
View Article and Find Full Text PDFAim: To compare the impact of two long-term weight-maintenance diets, a high protein (HP) and low glycaemic index (GI) diet versus a moderate protein (MP) and moderate GI diet, combined with either high intensity (HI) or moderate intensity physical activity (PA), on the incidence of type 2 diabetes (T2D) after rapid weight loss.
Materials And Methods: A 3-year multicentre randomized trial in eight countries using a 2 x 2 diet-by-PA factorial design was conducted. Eight-week weight reduction was followed by a 3-year randomized weight-maintenance phase.
Microglia, a type of CNS immune cell, have been shown to contribute to ethanol-activated neuronal death of the stress regulatory proopiomelanocortin (POMC) neuron-producing β-endorphin peptides in the hypothalamus in a postnatal rat model of fetal alcohol spectrum disorders. We determined whether the microglial extracellular vesicle exosome is involved in the ethanol-induced neuronal death of the β-endorphin neuron. Extracellular vesicles were prepared from hypothalamic tissues collected from postnatal rats (both males and females) fed daily with 2.
View Article and Find Full Text PDFBackground: Physical activity, sedentary time and sleep have been shown to be associated with cardio-metabolic health. However, these associations are typically studied in isolation or without accounting for the effect of all movement behaviours and the constrained nature of data that comprise a finite whole such as a 24 h day. The aim of this study was to examine the associations between the composition of daily movement behaviours (including sleep, sedentary time (ST), light intensity physical activity (LIPA) and moderate-to-vigorous activity (MVPA)) and cardio-metabolic health, in a cross-sectional analysis of adults with pre-diabetes.
View Article and Find Full Text PDFNutrients
June 2017
Type-2 diabetes (T2D) is one of the fastest growing chronic diseases worldwide. The PREVIEW project has been initiated to find the most effective lifestyle (diet and physical activity) for the prevention of T2D, in overweight and obese participants with increased risk for T2D. The study is a three-year multi-centre, 2 × 2 factorial, randomised controlled trial.
View Article and Find Full Text PDFBackground: Opioid receptors are known to control neurotransmission of various peptidergic neurons, but their potential role in regulation of microglia and neuronal cell communications is unknown. We investigated the role of mu-opioid receptors (MOR) and delta-opioid receptors (DOR) on microglia in the regulation of apoptosis in proopiomelanocortin (POMC) neurons induced by neonatal ethanol in the hypothalamus.
Methods: Neonatal rat pups were fed a milk formula containing ethanol or control diets between postnatal days 2-6.
Induction of neuroimmune genes by binge drinking increases neuronal excitability and oxidative stress, contributing to the neurobiology of alcohol dependence and causing neurodegeneration. Ethanol exposure activates signaling pathways featuring high-mobility group box 1 and Toll-like receptor 4 (TLR4), resulting in induction of the transcription factor nuclear factor kappa-light-chain-enhancer of activated B cells, which regulates expression of several cytokine genes involved in innate immunity, and its target genes. This leads to persistent neuroimmune responses to ethanol that stimulate TLRs and/or certain glutamate receptors (i.
View Article and Find Full Text PDFAlcohol abuse is often associated with disrupted circadian rhythms and sleep, and the link seems to be bidirectional. In addition, it has been shown that exposure to constant illumination may increase lipid peroxidation in tissues. In this study, we investigated the effects of circadian rhythm disruption (CRD) and chronic alcohol intake (A) alone and in combination (CRD+A), on the oxidative stress in total rat brain homogenate.
View Article and Find Full Text PDFThe etiology of autism spectrum disorders (ASDs) still remains unclear and seems to involve a considerable overlap between polygenic, epigenetic and environmental factors. We have summarized the current understanding of the interplay between gene expression dysregulation via epigenetic modifications and the potential epigenetic impact of environmental factors in neurodevelopmental deficits. Furthermore, we discuss the scientific controversies of the relationship between prenatal exposure to alcohol and alcohol-induced epigenetic dysregulations, and gene expression alterations which are associated with disrupted neural plasticity and causal pathways for ASDs.
View Article and Find Full Text PDFAlcohol Clin Exp Res
January 2015
Background: Alcohol exposure has adverse effects on stress physiology and behavioral reactivity. This is suggested to be due, in part, to the effect of alcohol on β-endorphin (β-EP)-producing neurons in the hypothalamus. In response to stress, β-EP normally provides negative feedback to the hypothalamic-pituitary-adrenal axis and interacts with other neurotransmitter systems in the amygdala to regulate behavior.
View Article and Find Full Text PDFBackground: Recently, retrograde tracing has provided evidence for an influence of hypothalamic β-endorphin (BEP) neurons on the liver, but functions of these neurons are not known. We evaluated the effect of BEP neuronal activation on alcohol-induced liver injury and hepatocellular cancer.
Methods: Male rats received either BEP neuron transplants or control transplants in the hypothalamus and were randomly assigned to feeding alcohol-containing liquid diet or control liquid diet for 8 weeks or to treatment of a carcinogen diethylnitrosamine (DEN).
β-Endorphin (BEP)-producing neuron in the hypothalamus plays a key role in bringing the stress axis to a state of homeostasis and maintaining body immune defense system. Long-term delivery of BEP to obtain beneficial effect on chemoprevention is challenging, as the peptides rapidly develop tolerance. Using rats as animal models, we show here that transplantation of BEP neurons into the hypothalamus suppressed carcinogens- and hormone-induced cancers in various tissues and prevented growth and metastasis of established tumors via activation of innate immune functions.
View Article and Find Full Text PDFBackground: We have previously shown that ethanol (EtOH) increases cellular apoptosis to developing neurons via the effects on oxidative stress of neurons directly and via increasing production of microglia-derived factors. To study further the mechanism of EtOH action on neuronal apoptosis, we determined the effects of 2 well-known PKA activators, dibutyryl cAMP (dbcAMP) and brain-derived neurotrophic factor (BDNF), on EtOH-activated oxidative stress and apoptotic processes in the hypothalamic neurons in the presence and absence of microglial cells' influence.
Methods: In enriched neuronal cells from fetal rat hypothalami treated with EtOH or with conditioned medium from EtOH-treated microglia, we measured cellular apoptosis by the free nucleosome assay and the levels of cAMP, BDNF, O²⁻, reactive oxygen species (ROS), nitrite, glutathione (GSH), and catalase following treatment with EtOH or EtOH-treated microglial culture conditioned medium.
The present study was undertaken to assess the effects of the natural antioxidant anthocyanins on learning and memory of rats in experimental model of oxidative stress. Our preliminary experiments demonstrated that disruption of diurnal rhythm via exposition of rats to constant light for 14 days caused excessive generation of free radicals in their brains. It is known that free radicals impair cognitive functions.
View Article and Find Full Text PDFObjectives: Epigenetics refers to the heritable, but reversible regulation of various biological functions. Changes in DNA methylation and chromatin structure derived from histone modifications are involved in the brain development, pathogenesis and pharmacotherapy of brain disorders.
Key Findings: Evidence suggests that epigenetic modulations play key roles in psychiatric diseases such as schizophrenia and bipolar disorder.
Alcohol Clin Exp Res
February 2013
Background: Animals exposed to alcohol during the developmental period develop many physiological and behavioral problems because of neuronal loss in various brain areas including the hypothalamus. Because alcohol exposure is known to induce oxidative stress in developing neurons, we tested whether hypothalamic cells from the fetal brain exposed to ethanol (EtOH) may alter the cell-cell communication between neurons and microglia, thereby leading to increased oxidative stress and the activation of apoptotic processes in the neuronal population in the hypothalamus.
Methods: Using enriched neuronal and microglial cells from fetal rat hypothalami, we measured cellular levels of various oxidants (O2 -, reactive oxygen species, nitrite), antioxidants (glutathione [GSH]), antioxidative enzymes (glutathione peroxidase [GSH-Px], catalase, superoxide dismutase) and apoptotic death in neurons in the presence and absence of EtOH or EtOH-treated microglial culture medium.
In the natural killer (NK) cells, δ-opiate receptor (DOR) and μ-opioid receptor (MOR) interact in a feedback manner to regulate cytolytic function with an unknown mechanism. Using RNK16 cells, a rat NK cell line, we show that MOR and DOR monomer and dimer proteins existed in these cells and that chronic treatment with a receptor antagonist reduced protein levels of the targeted receptor but increased levels of opposing receptor monomer and homodimer. The opposing receptor-enhancing effects of MOR and DOR antagonists were abolished following receptor gene knockdown by siRNA.
View Article and Find Full Text PDFOsteoporosis is a common age-related disorder and causes acute and long-term disability and economic cost. Many factors influence the accumulation of bone minerals, including heredity, diet, physical activity, gender, endocrine functions, and risk factors such as alcohol, drug abuse, some pharmacological drugs or cigarette smoking. The pathology of bone development during intrauterine life is a factor for osteoporosis.
View Article and Find Full Text PDFIt is becoming increasingly clear that stressful life events can affect cancer growth and metastasis by modulating nervous, endocrine, and immune systems. The purpose of this review is to briefly describe the process by which stress may potentiate carcinogenesis and how reducing body stress may prevent cancer growth and progression. The opioid peptide β-endorphin plays a critical role in bringing the stress axis to a state of homeostasis.
View Article and Find Full Text PDFNeurobehavioral stress has been shown to promote tumor growth and progression and dampen the immune system. In this study, we investigated whether inhibiting stress hormone production could inhibit the development of mammary carcinoma and metastasis in a rat model of breast carcinogenesis. To enhance β-endorphin (BEP), the endogenous opioid polypeptide that boosts immune activity and decreases stress, we generated BEP neurons by in vitro differentiation from fetal neuronal stem cells and transplanted them into the hypothalami of rats subjected to breast carcinogenesis.
View Article and Find Full Text PDFAlcohol Clin Exp Res
November 2010
Background: Microglia are the major inflammatory cells in the central nervous system and play a role in brain injuries as well as brain diseases. In this study, we determined the role of microglia in ethanol's apoptotic action on neuronal cells obtained from the mediobasal hypothalamus and maintained in primary cultures. We also tested the effect of cAMP, a signaling molecule critically involved in hypothalamic neuronal survival, on microglia-mediated ethanol's neurotoxic action.
View Article and Find Full Text PDFAlcohol Clin Exp Res
September 2010
Background: Ethanol exposure during early life has been shown to permanently alter the circadian expression of clock regulatory genes and the beta-endorphin precursor proopiomelanocortin (POMC) gene in the hypothalamus. Ethanol also alters the stress- and immune-regulatory functions of beta-endorphin neurons in laboratory rodents. Our aim was to determine whether the circadian clock regulatory Per2 gene modulates the action of ethanol on beta-endorphin neurons in mice.
View Article and Find Full Text PDFChronic alcohol consumption has been shown to decrease the activity of natural killer (NK) cell cytolytic function and the production of various cytokines from the spleen. We have recently shown that naltrexone, an opiate receptor antagonist, when administered for a period of 2 weeks suppresses micro-opiate receptor binding but increases partial differential-opiate receptor activity in rat splenocytes. However, the effects of long-term naltrexone treatment on alcohol-induced alteration of NK cell cytolytic activity and cytokines production in splenocytes have not been determined.
View Article and Find Full Text PDFBackground: Natural killer (NK) cell dysfunction is associated with hyperresponse of corticotropin releasing hormone (CRH) to immune challenge and with a loss of beta-endorphin (BEP) neurons in fetal alcohol exposed animals. Recently, we established a method to differentiate neural stem cells into BEP neurons using cyclic adenosine monophosphate (cAMP)-elevating agents in cultures. Hence, we determined whether in vitro differentiated BEP neurons could be used for reversing the compromised stress response and immune function in fetal alcohol exposed rats.
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