Open Access. Powered by Scholars. Published by Universities.®

Medicine and Health Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 20 of 20

Full-Text Articles in Medicine and Health Sciences

Central Administrations Of Palmitic Acid And Arachidonic Acid Decrease Central Leptin Sensitivity In Mice, L Cheng, Xu-Feng Huang, Y Yu Jun 2016

Central Administrations Of Palmitic Acid And Arachidonic Acid Decrease Central Leptin Sensitivity In Mice, L Cheng, Xu-Feng Huang, Y Yu

Xu-Feng Huang

Purpose: Leptin inhibits feeding and increases energy expenditure through the central nervous system. High-fat diet with saturated fatty acids (SFA) or n-6 polyunsaturated fatty acids (n-6 PUFA) has been reported to induce central leptin resistance and obesity. However, little is known if central administration of SFA or n-6 PUFA can reduce central leptin sensitivity. This study examined the central leptin sensitivity in response to intracerebroventricular (i.c.v.) injection of SFA, palmitic acid (PA) and n-6 PUFA, arachidonic acid (ARA) in mice. Methods: After overnight fasting, C57BL/6J male mice (n=24/group) were i.c.v. injected with either PA (50pmol/2ul), ARA (50pmol/2ul) or vehicle (saline, …


A Neuregulin 1 Transmembrane Domain Mutation Causes Imbalanced Glutamatergic And Dopaminergic Receptor Expression In Mice, K A. Newell, T Karl, Xu-Feng Huang Jun 2016

A Neuregulin 1 Transmembrane Domain Mutation Causes Imbalanced Glutamatergic And Dopaminergic Receptor Expression In Mice, K A. Newell, T Karl, Xu-Feng Huang

Xu-Feng Huang

The neuregulin 1 gene has repeatedly been identified as a susceptibility gene for schizophrenia, thus mice with genetic mutations in this gene offer a valuable tool for studying the role of neuregulin 1 in schizophrenia-related neurotransmission. In this study, slide-based receptor autoradiography was used to quantify glutamatergic N-methyl-d-aspartate (NMDA), dopaminergic D2, cannabinoid CB1 and acetylcholine M1/4 receptor levels in the brains of male heterozygous transmembrane domain neuregulin 1 mutant (Nrg1+/−) mice at two ages. Mutant mice expressed small but significant increases in NMDA receptor levels in the cingulate cortex (7%, p = 0.044), sensory cortex (8%, p = 0.024), and …


A Neuregulin 1 Transmembrane Domain Mutation Causes Imbalanced Glutamatergic And Dopaminergic Receptor Expression In Mice, K A. Newell, T Karl, Xu-Feng Huang Jun 2016

A Neuregulin 1 Transmembrane Domain Mutation Causes Imbalanced Glutamatergic And Dopaminergic Receptor Expression In Mice, K A. Newell, T Karl, Xu-Feng Huang

Xu-Feng Huang

The neuregulin 1 gene has repeatedly been identified as a susceptibility gene for schizophrenia, thus mice with genetic mutations in this gene offer a valuable tool for studying the role of neuregulin 1 in schizophrenia-related neurotransmission. In this study, slide-based receptor autoradiography was used to quantify glutamatergic N-methyl-d-aspartate (NMDA), dopaminergic D2, cannabinoid CB1 and acetylcholine M1/4 receptor levels in the brains of male heterozygous transmembrane domain neuregulin 1 mutant (Nrg1+/−) mice at two ages. Mutant mice expressed small but significant increases in NMDA receptor levels in the cingulate cortex (7%, p = 0.044), sensory cortex (8%, p = 0.024), and …


Distinct Neurobehavioural Effects Of Cannabidiol In Transmembrane Domain Neuregulin 1 Mutant Mice, Leonora E. Long, Rose Chesworth, Xu-Feng Huang, Alexander Wong, Adena Spiro, Iain S. Mcgregor, Jonathon Arnold, Tim Karl Feb 2013

Distinct Neurobehavioural Effects Of Cannabidiol In Transmembrane Domain Neuregulin 1 Mutant Mice, Leonora E. Long, Rose Chesworth, Xu-Feng Huang, Alexander Wong, Adena Spiro, Iain S. Mcgregor, Jonathon Arnold, Tim Karl

Xu-Feng Huang

The cannabis constituent cannabidiol (CBD) possesses anxiolytic and antipsychotic properties. We have previously shown that transmembrane domain neuregulin 1 mutant (Nrg1 TM HET) mice display altered neurobehavioural responses to the main psychoactive constituent of cannabis, D9-tetrahydrocannabinol. Here we investigated whether Nrg1 TM HET mice respond differently to CBD and whether CBD reverses schizophrenia-related phenotypes expressed by these mice. Adult male Nrg1 TM HET and wild type-like littermates (WT) received vehicle or CBD (1, 50 or 100 mg/kg i.p.) for 21 days. During treatment and 48 h after withdrawal we measured behaviour, whole blood CBD concentrations and autoradiographic receptor binding. Nrg1 …


Diet High In Oat Β-Glucan Activates The Gut-Hypothalamic (Pyy3-36-Npy) Axis And Increases Satiety In Diet-Induced Obesity In Mice, Xu-Feng Huang, Yinghua Yu, Eleanor Beck, Timothy South, Yulin Li, Marijka Batterham, Linda Tapsell, Jiezhong Chen Feb 2013

Diet High In Oat Β-Glucan Activates The Gut-Hypothalamic (Pyy3-36-Npy) Axis And Increases Satiety In Diet-Induced Obesity In Mice, Xu-Feng Huang, Yinghua Yu, Eleanor Beck, Timothy South, Yulin Li, Marijka Batterham, Linda Tapsell, Jiezhong Chen

Xu-Feng Huang

This study tested the effects of (1-3),(1-4) b-D-glucan from oats, on activation of the guthypothalamic (PYY3–36-NPY) axis, satiety, and weight loss in diet-induced obesity (DIO) mice. DIO mice were fed standard lab chow diets or varied doses of b-glucan for 6 weeks. Energy intake, satiety, body weight changes and peptide Y-Y3-36 (PYY3-36) were measured together with a satiety test and measurement of neuropeptide Y (NPY) mRNA expression in the hypothalamic arcuate nucleus (Arc). The average energy intake (-13%, po0.05) and body weight gain was lower with increasing b-glucan over 6 wk with acute suppression of energy intake over 4 h. …


Metabolic Parameters And Emotionality Are Little Affected In G-Protein Coupled Receptor 12 (Gpr12) Mutant Mice, Elisabeth Frank, Yizhen Wu, Naomi Piyaratna, William James Body, P Snikeris, Timothy South, Anna-Karin Gerdin, Mikael Bjursell, Mohammad Bohlooly-Y, Leonard H. Storlien, Xu-Feng Huang Feb 2013

Metabolic Parameters And Emotionality Are Little Affected In G-Protein Coupled Receptor 12 (Gpr12) Mutant Mice, Elisabeth Frank, Yizhen Wu, Naomi Piyaratna, William James Body, P Snikeris, Timothy South, Anna-Karin Gerdin, Mikael Bjursell, Mohammad Bohlooly-Y, Leonard H. Storlien, Xu-Feng Huang

Xu-Feng Huang

Background: G-protein coupled receptors (GPR) bear the potential to serve as yet unidentified drug targets for psychiatric and metabolic disorders. GPR12 is of major interest given its putative role in metabolic function and its unique brain distribution, which suggests a role in emotionality and affect. We tested Gpr12 deficient mice in a series of metabolic and behavioural tests and subjected them to a well-established high-fat diet feeding protocol. Methodology/Principal Findings: Comparing the mutant mice with wild type littermates, no significant differences were seen in body weight, fatness or weight gain induced by a high-fat diet. The Gpr12 mutant mice displayed …


Inter-Meal Interval Is Increased In Mice Fed A High Whey, As Opposed To Soy And Gluten, Protein Diets, Xu-Feng Huang, Timothy South, Yinghua Yu Sep 2012

Inter-Meal Interval Is Increased In Mice Fed A High Whey, As Opposed To Soy And Gluten, Protein Diets, Xu-Feng Huang, Timothy South, Yinghua Yu

Xu-Feng Huang

This study aimed to characterise meal patterns and satiety effects of diets that are high in protein but differ in protein source. Using a computerised automatic recording system, meal pattern behaviour was recorded continuously for 7 days in mice fed single (whey, soy or gluten) or different combined protein diets. Overall, average energy intake was significantly lower in mice fed a whey protein diet than those fed soy, gluten and lab chow diets. Among these four diets, the inter-meal interval of mice fed a whey protein diet was the longest and their meal number was the lowest. Combination of whey …


Ventromedial Hypothalamic Npy Y2 Receptor In The Maintenance Of Body Weight In Diet-Induced Obesity In Mice, Yulin Li, Xu-Feng Huang, Chao Deng, Qing Wang, Timothy South, Yinghua Yu Sep 2012

Ventromedial Hypothalamic Npy Y2 Receptor In The Maintenance Of Body Weight In Diet-Induced Obesity In Mice, Yulin Li, Xu-Feng Huang, Chao Deng, Qing Wang, Timothy South, Yinghua Yu

Xu-Feng Huang

This study examined changes in neuropeptide Y (NPY) Y2 receptor binding in the brains of C57BL/6 mice in response to different levels of high-fat diets via three dietary intervention methods: high-fat diet, switching from high- to low-fat diet and finally, energy restricted high-fat diet. Forty-five C57Bl/6 male mice were fed a high-fat diet for 8 weeks and then classified as diet-induced obese (DIO) or diet-resistant (DR) mice according to the highest and lowest body weight gainers, respectively. The DIO and DR mice were then randomly divided into three groups each and either continued on their high-fat diet ad libitum (DIO-H …


Obese Reversal By A Chronic Energy Restricted Diet Leaves An Increased Arc Npy/Agrp, But No Alteration In Pomc/Cart, Mrna Expression In Diet-Induced Obese Mice, Xu-Feng Huang, Chao Deng, Yinghua Yu Sep 2012

Obese Reversal By A Chronic Energy Restricted Diet Leaves An Increased Arc Npy/Agrp, But No Alteration In Pomc/Cart, Mrna Expression In Diet-Induced Obese Mice, Xu-Feng Huang, Chao Deng, Yinghua Yu

Xu-Feng Huang

No abstract provided.


A Behavioural Comparison Of Acute And Chronic Δ9-Tetrahydrocannabinol And Cannabidiol In C57bl/6jarc Mice, Ian Mcgregor, Xu-Feng Huang, Tim Karl, Jonathon Arnold, Rose Chesworth, Leonora E. Long Sep 2012

A Behavioural Comparison Of Acute And Chronic Δ9-Tetrahydrocannabinol And Cannabidiol In C57bl/6jarc Mice, Ian Mcgregor, Xu-Feng Huang, Tim Karl, Jonathon Arnold, Rose Chesworth, Leonora E. Long

Xu-Feng Huang

Cannabis contains over 70 unique compounds and its abuse is linked to an increased risk of developing schizophrenia. The behavioural profiles of the psychotropic cannabis constituent Δ9-tetrahydrocannabinol (Δ9-THC) and the non-psychotomimetic constituent cannabidiol (CBD) were investigated with a battery of behavioural tests relevant to anxiety and positive, negative and cognitive symptoms of schizophrenia. Male adult C57BL/6JArc mice were given 21 daily intraperitoneal injections of vehicle, Δ9-THC (0.3, 1, 3 or 10 mg/kg) or CBD (1, 5, 10 or 50 mg/kg). Δ9-THC produced the classic cannabinoid CB1 receptor-mediated tetrad of hypolocomotion, analgesia, catalepsy and hypothermia while CBD had modest hyperthermic effects. …


Effects Of Diets High In Whey, Soy, Red Meat And Milk Protein On Body Weight Maintenance In Diet-Induced Obesity In Mice, Xu-Feng Huang, Y Liu, Gita Rahardjo, Peter Mclennan, Linda Tapsell, William Buttemer Sep 2012

Effects Of Diets High In Whey, Soy, Red Meat And Milk Protein On Body Weight Maintenance In Diet-Induced Obesity In Mice, Xu-Feng Huang, Y Liu, Gita Rahardjo, Peter Mclennan, Linda Tapsell, William Buttemer

Xu-Feng Huang

This study examined the effects of different food sources of protein on energy intake, body weight maintenance, and on the responses of plasma leptin, insulin and adiponectin in chronic high-fat diet-induced obese mice. Obesity was induced in 47 mice with a high-fat diet for 20 weeks. They were divided into five diet groups to test the effects of a higher protein proportion (30% energy), achieved at the expense of carbohydrate. For the next eight weeks, four of the groups were fed diets of chow formulated with whey, soy, red meat or milk while the control group continued on their high-fat …


Temporal And Site-Specific Brain Alterations In Cb1 Receptor Binding In High Fat Diet-Induced Obesity In C57bl/6 Mice, Xu-Feng Huang, Timothy South Sep 2012

Temporal And Site-Specific Brain Alterations In Cb1 Receptor Binding In High Fat Diet-Induced Obesity In C57bl/6 Mice, Xu-Feng Huang, Timothy South

Xu-Feng Huang

The cannabinoid CB1 receptor has been implicated in the regulation of appetite and the consumption of palatable foods. This experiment aimed to explore the involvement of the CB1 receptor in the early and late stages of high fat diet-induced obesity in C57BL/6 mice. The C57Bl/6 mice were placed on a high fat (HF) or low fat/high carbohydrate (LF) diet for 3 or 20 weeks. Quantitative autoradiography revealed that binding of [3H] CP-55,940 (CB1 receptor ligand) was elevated following 3 weeks of HF feeding in areas including the medial/ventral anterior olfactory nucleus (22.1%), agranular insular cortex (24.0%) and the hypothalamus (31.5%) …


G Protein-Coupled Receptor 12 Deficiency Results In Decreased Energy Expenditure, Dyslipidemia And Obesity In Mice, L. Svensson, Xu-Feng Huang, M Jonnson, M Bjursell, M Boholooly, J Tornell, V Surve, A Gerdin Sep 2012

G Protein-Coupled Receptor 12 Deficiency Results In Decreased Energy Expenditure, Dyslipidemia And Obesity In Mice, L. Svensson, Xu-Feng Huang, M Jonnson, M Bjursell, M Boholooly, J Tornell, V Surve, A Gerdin

Xu-Feng Huang

No abstract provided.


Differential Expression Of Dopamine D2 And D4 Receptor And Tyrosine Hydroxylase Mrna In Mice Prone, Or Resistant, To Chronic High-Fat Diet-Induced Obesity, Xu-Feng Huang, Yinghua Yu, Katerina Zavitsanou, Mei Han, Leonard Storlien Sep 2012

Differential Expression Of Dopamine D2 And D4 Receptor And Tyrosine Hydroxylase Mrna In Mice Prone, Or Resistant, To Chronic High-Fat Diet-Induced Obesity, Xu-Feng Huang, Yinghua Yu, Katerina Zavitsanou, Mei Han, Leonard Storlien

Xu-Feng Huang

The present study examined brain dopamine D2 and D4 receptor and tyrosine hydroxylase (TH) mRNA expression in chronic high-fat diet-induced obese (cDIO) and obese-resistant (cDR) mice. Twenty-eight mice were fed a high-fat diet (HF: 40% of calories from fat) for 6 weeks and then classified as cDIO (n = 8) or cDR (n = 8) mice according to the highest and lowest body weight gainers, respectively. Seven mice were fed a low-fat diet (LF: 10% of calories from fat) and used as controls. After 20 weeks of feeding, visceral fat per gram of initial body weight was significantly higher in …


Diets High In Oat-Derived Beta-Glucan Promote Negative Energy Regulatory Pathway Of Hypothalamic Npy System In Chronic Diet-Induced Obesity In Mice, Xu-Feng Huang, Timothy South, Eleanor Beck, Marijka Batterham, K. Grinter, Linda Tapsell Sep 2012

Diets High In Oat-Derived Beta-Glucan Promote Negative Energy Regulatory Pathway Of Hypothalamic Npy System In Chronic Diet-Induced Obesity In Mice, Xu-Feng Huang, Timothy South, Eleanor Beck, Marijka Batterham, K. Grinter, Linda Tapsell

Xu-Feng Huang

No abstract provided.


Dopamine Transporter And D2 Receptor Densities In Mice Prone Or Resistant To Chronic High-Fat Diet-Induced Obesity, Xu-Feng Huang, F Chen, A Lawrence, Katerina Zavitsanou, Chao Deng, Hong-Qin Wang, Yinghua Yu Sep 2012

Dopamine Transporter And D2 Receptor Densities In Mice Prone Or Resistant To Chronic High-Fat Diet-Induced Obesity, Xu-Feng Huang, F Chen, A Lawrence, Katerina Zavitsanou, Chao Deng, Hong-Qin Wang, Yinghua Yu

Xu-Feng Huang

No abstract provided.


High-Fat Diet Exposure Increases Dopamine D2 Receptor And Decreases Dopamine Transporter Receptor Binding Density In The Nucleus Accumbens And Caudate Putamen Of Mice, Xu-Feng Huang, Timothy South Sep 2012

High-Fat Diet Exposure Increases Dopamine D2 Receptor And Decreases Dopamine Transporter Receptor Binding Density In The Nucleus Accumbens And Caudate Putamen Of Mice, Xu-Feng Huang, Timothy South

Xu-Feng Huang

No abstract provided.


Energy-Restricted Pair-Feeding Normalizes Low Levels Of Brain-Derived Neurotrophic Factor/Tyrosine Kinase B Mrna Expression In The Hippocampus, But Not Ventromedial Hypothalamic Nucleus, In Diet-Induced Obese Mice, Xu-Feng Huang, Qing Wang, Yinghua Yu Sep 2012

Energy-Restricted Pair-Feeding Normalizes Low Levels Of Brain-Derived Neurotrophic Factor/Tyrosine Kinase B Mrna Expression In The Hippocampus, But Not Ventromedial Hypothalamic Nucleus, In Diet-Induced Obese Mice, Xu-Feng Huang, Qing Wang, Yinghua Yu

Xu-Feng Huang

Brain-derived neurotrophic factor (BDNF) and its receptor tyrosine kinase B (TrkB) are closely associated with the regulation of energy homeostasis, but their roles in diet-induced obesity have not been explored. Using dietary interventions, this study examined regional changes of BDNF and TrkB mRNA expression in different brain regions of diet-induced obese (DIO) and resistant (DR) mice in response to high-fat (HF), energy-restricted pair-feeding and low fat (LF) diets. Using in situ hybridization, DIO mice had significantly decreased levels of BDNF mRNA expression (¿32% to ¿37%) and TrkB (¿21% to ¿23%) in the hippocampus compared to DR mice on an HF …


Decreased Plasma Peptide Yy Accompanied By Elevated Peptide Yy And Y2 Receptor Binding Densities In The Medulla Oblongata Of Diet-Induced Obese Mice, Xu-Feng Huang, Chao Deng, Yean Tan, Gita Rahardjo Sep 2012

Decreased Plasma Peptide Yy Accompanied By Elevated Peptide Yy And Y2 Receptor Binding Densities In The Medulla Oblongata Of Diet-Induced Obese Mice, Xu-Feng Huang, Chao Deng, Yean Tan, Gita Rahardjo

Xu-Feng Huang

It is well known that the peripheral peptide YY (PYY)-central neuropeptide Y (NPY) Y2 receptor axis plays an important role in promoting negative energy balance regulation. Both the hypothalamus and medulla oblongata express a high level of Y2 receptors; however, the functional role of this receptor in chronic high-fat diet-induced obesity has not been fully examined. Using quantitative autoradiography, this study measured binding densities of total [125I]PYY and Y2 receptors in the hypothalamus and medulla of chronic high-fat diet-induced obese (DIO), obese-resistant, and low-fat-fed mice. Plasma PYY was also measured using RIA after 22 wk of dietary intervention. The results …


Transmembrane Domain Nrg1 Mutant Mice Show Altered Susceptibility To The Neurobehavioural Actions Of Repeated Thc Exposure In Adolescence, Leonora Long, Rose Chesworth, Xu-Feng Huang, Iain Mcgregor, Jonathon Arnold, Tim Karl Sep 2012

Transmembrane Domain Nrg1 Mutant Mice Show Altered Susceptibility To The Neurobehavioural Actions Of Repeated Thc Exposure In Adolescence, Leonora Long, Rose Chesworth, Xu-Feng Huang, Iain Mcgregor, Jonathon Arnold, Tim Karl

Xu-Feng Huang

Heavy cannabis abuse increases the risk of developing schizophrenia. Adolescents appear particularly vulnerable to the development of psychosis-like symptoms after cannabis use. To test whether the schizophrenia candidate gene neuregulin 1 (NRG1) modulates the effects of cannabinoids in adolescence, we tested male adolescent heterozygous transmembrane domain Nrg1 mutant (Nrg1 TM HET) mice and wild type-like littermates (WT) for their neurobehavioural response to repeated Δ9-tetrahydrocannabinol (THC, 10 mg/kg i.p. for 21 d starting on post-natal day 31). During treatment and 48 h after treatment withdrawal, we assessed several behavioural parameters relevant to schizophrenia. After behavioural testing we measured autoradiographic …