Feeding behavior and gene expression of appetite-related neuropeptides in mice lacking for neuropeptide Y Y5 receptor subclass

Neuropeptide Y (NPY) is a potent neurotransmitter for feeding. Besides NPY, orexigenic neuropeptides such as agouti-related protein (AgRP), and anorexi- genic neuropeptides such as α-melatonin stimulating hormone (MSH) and cocaine-amphetamine-regulated transcript (CART) are also involved in central feeding regulation. During fasting, NPY and AgRP gene expressions are up-regulated and POMC and CART gene ex- pressions are down-regulated in hypothalamus. Based on the network of peptidergic neurons, the former are involved in positive feeding regulation, and the latter are involved in negative feeding, which exert these feeding-regulated peptides especially in paraventricular nucleus (PVN). To clarify the compensatory mecha- nism of knock-out of NPY system on feeding, change in gene expressions of appetite-related neuropeptides and the feeding behavior was studied in NPY Y5-KO mice. Food intake was increased in Y5-KO mice. Fasting increased the amounts of food and water intake in the KO mice more profoundly. These data indicated the compensatory phenomenon of feeding behavior in Y5-KO mice. RT-PCR and ISH suggested that the compensation of feeding is due to change in gene expressions of AgRP, CART and POMC in hypothalamus. Thus, these fi ndings indicated that the compensatory mechanism involves change in POMC/CART gene expression in arcuate nucleus (ARC). The POMC/CART gene expression is important for central compensatory regulation in feeding behavior.

Neuropeptide Y promotes TGF-β1 production in RAW264.7 cells by activating PI3K pathway via Y1 receptor

Objective To examine the effect of neuropeptide Y （NPY） on TGF-β1 production in RAW264.7 macrophages. Methods Enzyme linked immunosorbent assay （ELISA） was used to detect TGF-β1 production. Cell counting kit 8 （CCK-8） was used to assay the viability of RAW264.7 cells. Western blot was used to detect the phosphorylation of PI3K p85. Results NPY treatment could promote TGF-β1 production and rapid phosphorylation of PI3K p85 in RAW264.7 cells via Y1 receptor. The elevated TGF-β 1 production induced by NPY could be abolished by wortrnannin pretreatment. Conclusion NPY may elicit TGF-β production in RAW264.7 cells via Y1 receptor, and the activated PI3K pathway may account for this effect.

Efficacy of Antisense Oligodeoxynucleotide of Neuropeptide Y Y5 Receptor on Treating of Hyperleptinemia by Intraventricular Administration in Diet-induced Obese Rats

Objective: To study the efficacy of antisense oligonucleotide of neuropeptide Y (NPY) Y5 receptor on treating hyperleptinemia by intracerebral ventricular administration in diet-induced obese rats.Methods: The obese rats were prepared by feeding a high-nutritive diet for 7 weeks. The lateral ventricle of obese rats was cannulated. Either 10 μl of different neuropeptide Y Y5 receptor oligodeoxynucleotide, including antisense, sense and missense oligodeoxynucleotide (5 g/L) or 10 μl saline was administered into the ventricle through cannula three times per day in every rat. Two days later the rats were slaughtered .The weights of both retroperitoneal and epididymal adipose tissues were measured, and the serum insulin and leptin were detected by radioimmunoassay method and the murine leptin ELISA kit respectively. Results: ①The level of serum was significantly higher in experimental rats than that in normal rats. Similarly, the level of serum insulin and the weights of both retroperitoneal and epididymal adipose tissues were increased in experimental rats. ②After the diet-induced obese rats were intraventricularly administered with NPY Y5 receptor antisense oligodeoxynucleotide, the levels of serum leptin and insulin were significantly decreased and combined with the reduction of weight in retroperitoneal adipose tissue. There was, however, no significant difference in the weight of epidymal adipose tissue between pre-treated and post-treated duration. ③There was significant positive correlation among the level of serum leptin, the level of serum insulin and the weight of retroperritoneal adipose tissue in diet-induced obese rats. Conclusion: Intracerebral ventricular administration of antisense oligodeoxynucleotide of neuropeptide Y Y5 receptor may alleviate hyperleptinemia in diet-induced obese rats and decrease the weight of retroperitoneal adipose tissue and the level of serum insulin.

Apoptosis and Lipolysis of White Adipocytes Induced by Neuropeptide Y- Y5 Receptor Antisense Oligodeoxynucleotides

Objective: To investigate the influence of central administration ofneuropeptide Y-Y5 receptor antisense oligodeoxynucleotides (ODNs) on body weight, fat pads of SDrats, and the effects of white adipocytes lipolysis and apoptosis. Methods: Y5 receptor antisense,sense, mismatched ODNs or vehicle was intracerebroventricularly (i. c. v.) injected. Averageadipocyte area was calculated. DNA ladders were measured to evaluate adipocyte apoptosis, and RT-PCRwas used to analyse the expression of Bcl-2 and Bax gene. Results: Central administration of Y5antisense ODNs significantly decreased body weight, and average adipocyte area. DNA fragmentationwas present after electrophoresis at epididymal adipose tissue. The expression of Bcl-2 gene wasdownregulated, while the expression of Bax upregulated. Conclusion: Lipolysis and adipocyteapoptosis may be important mechanisms far 75 antisense therapy.

人胎视皮质皮质下层NPY－IR神经元的发育

本文用免疫组化方法研究了１６周至足月人胎视皮质皮质下层ＮＰＹ－ＩＲ神经元的发育。各胎龄视皮质ＳＰ层内均有ＮＰＹ－ＩＲ神经元分布。从１６周至２６周，ＮＰＹ－ＩＲ神经元密度逐渐增高并于２６周达高峰；３２周以后阳性神经元密度随胎龄增长而下降。人胎视皮质ＳＰ层ＮＰＹ－ＩＲ神经元形态也随胎龄而变化；２０周以前，ＮＰＹ－ＩＲ神经元大多是胞体较小，突起短而少的未分化神经元、ＳＰ层内ＮＰＹ－ＩＲ纤维少。２０周以后，ＮＰＹ－ＩＲ神经元胞体增大，突起增多、变长；多极和双极、双簇神经元随胎龄增长而增多；ＳＰ层内的ＮＰＹ－ＩＲ纤维大量增加，部分纤维穿入皮质板。３２周以后，多极ＮＰＹ－ＩＲ神经元逐渐减少，双极双簇神经元所占比例相对增高。ＮＰＹ免疫组化结合ＮＡＤＰＨ－ｄ组化显示人胎视皮质ＳＰ层大多数ＮＰＹ－ＩＲ神经元同时呈ＮＯＳ阳性。本研究观察到人胎视皮质ＳＰ层内ＮＰＹ－ＩＲ神经元发育可分为发生、成熟和退化三个阶段。

Neuropeptide Y and leptin receptor expression in the hypothalamus of rats with chronic immobilization stress

In this study, Sprague-Dawley rats were immobilized to a frame for 3 hours a day for 21 days to establish a model of chronic immobilization stress. The body weight and food intake of rats subjected to chronic immobilization stress were significantly decreased compared with the control group. Dual-labeling immunofluorescence revealed that the expression of leptin receptor and the co-localization coeffient in these leptic receptor neurons in the arcuate nucleus of the hypothalamus were both upregulated, while the number of neuropeptide Y neurons was decreased. Chronic immobilization stress induced high expression of leptin receptor in the arcuate nucleus and suppressed the synthesis and secretion of neuropeptide Y, thereby disrupting the pathways in the arcuate nucleus that regulate feeding behavior, resulting in diminished food intake and reduced body weight.

Associations of Gonadotropin-Releasing Hormone Receptor (GnRHR) and Neuropeptide Y(NPY) Genes’Polymorphisms with Egg-Laying Traits in Wenchang Chicken

Single nucleotide polymorphisms （SNP） of chicken gonadotropin-releasing hormone receptor （GnRHR） and neuropeptide Y （NPY） were selected to identify the genotypes of Wenchang （Chinese indigenous breed） chicken with restricton fragment length polymorphisms. The associations of the SNPs with the total egg production （NE）, average days of continual laying （ADCL）, and number of double-yolked eggs （DYE） traits were analyzed. The frequency of restriction enzyme A/a alleles in the population was for GnRHR 0.69 （Bpu1102 Ⅰ A） and 0.31 （Bpu1102 Ⅰ a） and for NPY 0.46 （Dra Ⅰ B） and 0.54 （Dra Ⅰ b）. Trait data from a total of 120 hens, which were purebred introduced from Hainan Province, China from one generation were recorded. Two significant effects of genes＇ marker were found： for GnRHR and number of eggs （dominant; t= 2.67, df= 116） and NPY and number of eggs （additive; t= 1.97, df= 116）. The current research supports the effects of GnRHR and NPY genes on egg-laying traits of chickens.

Leptin transiently antagonizes ghrelin and long-lastingly orexin in regulation of Ca^(2+) signaling in neuropeptide Y neurons of the arcuate nucleus

AIM： To explore the mechanism for interactions of leptin with ghrelin and orexin in the arcuate nucleus （ARC） activating neuropeptide Y （NPY） neurons during physiological regulation of feeding, METHODS： Single neurons from ARC of adult rats with matured feeding function were isolated. [Ca2＋]i was measured to monitore their activities. The time course of leptin effects on ghrelin-induced versus orexin-induced [Ca2＋]i increases in NPY neurons was studied. RESULTS： Administration of ghrelin or orexin-A at 101~ mol/L increased cytosolic Ca2~ concentration （[Ca2＋]~） in NPY neurons isolated from the ARC of adult rats. Upon administration of leptin at 10^-14-10^-12 mol/L, ghrelin-induced [Ca2＋]i increases were initially （〈 10 min） inhibited but later restored, exhibiting a transient pattern of inhibition. In contrast, orexin-induced [Ca2＋]i increases were inhibited by leptin in a long- lasting manner. Furthermore, a prior administration of leptin inhibited orexin action but not ghrelin action to increase ICa 2＋li, CONCLUSION： Leptin counteracted ghrelin effects transiently and orexin effects long-lastingly in NPY neurons. The transient property with which leptin counteracts ghrelin action in NPY neurons may allow the fasting-associated increase in ghrelin levels to activate NPY neurons in the presence of physiological leptin and to stimulate feeding.

The Role of β3-adrenergic Receptor Gene in Neuropeptide Y Y5Receptor Antisense Gene Therapy of Diet-induced Obese Rats

Objective: To study the role of β3-adrenergic receptor gene in neuropeptide Y(NPY) Y5 receptor antisense gene therapy of diet-induced obese rats.Methods: The diet-induced obese rats were prepared by feeding a high-nutrition diet. Lateral ventricular was cannulated in obese rats which then received an intraventricular injection of either 5 μg/μl NPY Y5 receptor antisense or 10 μl missense oligodeoxynucleotide or saline of 10 μl respectively in every rat. When the rats were killed, the wet weight of abdominal adipose tissue, the level of serum lipid and lipoprotein were measured. Total RNA from the retroperitoneal adipose tissue was extracted and the level of β3-adrenergic receptor gene mRNA expression was evaluated by RT-PCR.Results: ①The wet weight of abdominal adipose tissue, the levels of serum lipids were greatly higher in diet-induced obese rats than those in normal rats. However, there were much lower β3-adrenergic receptor gene mRNA expression levels in retroperitoneal adipose tissue in diet-induced obese rats as compared with those in normal rats. ②After the diet-induced obese rats were intraventricularly administered with NPY Y5 receptor antisense oligodeoxynucleotide, the levels of β3-adrenergic receptor gene mRNA expression in retroperitoneal adipose tissue of diet-induced obese rats were strikingly up-regulated, whereas the wet weight of abdominal adipose tissue, the levels of serum lipids were markedly reduced.Conclusion: Intraventricular administration of antisense oligodeoxynucleotide to NPY Y5 receptor could significantly reduce the abdominal adipose tissue and the levels of serum lipids in diet-induced obese rats by up-regulating the level of β3-adrenergic receptor gene mRNA expression in retroperitoneal adipose tissue.

Type-dependent differential expression of neuropeptide Y in chicken hypothalamus (Gallus domesticus)

Neuropeptide Y （NPY） is one of the most important orexigenic agents in central regulation of feeding behavior, body weight and energy homeostasis in domestic chickens. To examine differences in the hypothalamic NPY between layer-type and meat-type of chickens, which are two divergent kinds of the domestic chickens in feeding behavior and body weight, we detected mRNA levels of NPY in hypothalamic infundibular nucleus （IN）, paraventricular nucleus （PVN） and lateral hypothalamic area （LHA） of these two types of chickens using one-step real time RT-PCR. The meat-type chicken had more food daily （about 1.7 folds） and greater body weights （about 1.5 folds） and brain weights than the layer-type chicken at the age of 14 d. In the meat-type of chicken, NPY mRNA levels of the IN and PVN were significantly greater than those of the LHA, and were not significantly different between the lN and PVN. However, in the layer-type of chicken, NPY mRNA levels were significantly greater in the IN than those in the LHA and PVN, and were not significantly different between the PVN and LHA. In all these hypothalamic regions the layer-type of chicken had significantly higher NPY mRNA levels than the meat-type chicken did. These results suggest the expression of NPY in the hypothalamus has a type-dependent pattern in domestic chickens.

Effects of acupuncture therapy on plasma neuropeptide Y levels and resuscitation in patients with very early stage acute cerebral infarction A randomized controlled study

BACKGROUND： It is known that acupuncture therapy can decrease plasma neuropeptide Y （NPY） levels in patients with cerebral infarction, but different types of acupuncture therapy used in various stages of cerebral infarction have not been evaluated. OBJECTIVE： To explore the effect of acupuncture therapy on resuscitation （Xingnao Kaiqiao） and plasma NPY levels in patients with very early stage acute cerebral infarction. DESIGN, TIME AND SETTING： This case-controlled study was performed at the Affiliated Hospital of the Medical College of the Chinese People＇s Armed Police Force between September 2004 and October 2005. PARTICIPANTS： Sixty patients with acute cerebral infarction of ≤ 6 hours were used in this study. Patients were randomly divided into an acupuncture therapy group （n = 30） and a routine treatment group （n = 30）. Another 30 healthy subjects were used as the control group. METHODS： The acupuncture therapy of Xingnao Kaiqiao used in the acupuncture therapy group was based on routine western medical treatment and was performed at bilateral Neiguan （PCG） using the twirling, reinforcing-reducing method, Renzhong （DU26） using heavy bird-pecking needling, Sanyinjiao （SPG） using reinforcing and reducing by lifting and thrusting the needle, Jiquan （HT1）, Weizhong （BL40） and Chize （LU5） using reinforcing and reducing by lifting and thrusting the needle. The acupuncture lasted for 14 days. Patients in the routine treatment group underwent routine medical treatment and no intervention was given to subjects in the control group. MAIN OUTCOME MEASURES： A 4 mL venous blood sample was obtained at different time points, i.e., immediately after hospitalization, the next morning, 7 and 14 days after treatment, to measure plasma NPY levels pre- and post-treatment using the radio-immunity method. RESULTS： The plasma NPY levels were significantly higher in both the routine treatment group and the acupuncture therapy group than in the control group pre- and post-treatment （P 〈 0.01）. In particular, the plasma NPY levels in both the acupuncture therapy group and the routine treatment group were increased 7 days post-treatment but decreased from 7-14 days post-treatment. In addition, the plasma NPY levels were significantly lower in the acupuncture therapy group than in the routine treatment group on day 7 and 14 post-treatment （P 〈 0.01）. CONCLUSION： Acupuncture therapy of Xingnao Kaiqiao can decrease plasma NPY levels in patients with very early stage acute cerebral infarction. In addition, the therapeutic effect of acupuncture with a prolonged therapy time is superior to routine treatment.

Influence of Ganoderma lucidum spores on the levels of neuropeptide Y and somatostatin in brains of seizure rats

BACKGROUND： Previous research has revealed that somatostatin can induce epilepsy, and that the levels of neuropeptide Y may increase and become more active in brain areas with epileptic seizures. OBJECTIVE： To observe the effect of Ganoderma luciclum spore powder on the neuropeptide Y and somatostatin content in the cerebral cortex and hippocampal regions of seizure rats induced by pentylenetetrazol （PTZ）. Furthermore, to verify any effect of Ganoderma lucidum spore powder on inhibition of epileptic seizures. DESIGN, TIME AND SETTING： A randomized group animal study was performed in August 2007 in the School of Basic Medical Sciences, Jiamusi University （Jiamusi, Heilongjiang, China）. MATERIALS： Thirty healthy, male, Wistar rats, aged 12 weeks and weighing 180-220 g, were taken as the experimental animals. PTZ （Sigma Company, United States） was used to induce epilepsy. Ganoderma lucidum spores （Leyss, ex Fr variety） were purchased from Jiamusi City Wild Growing Case of the Ganoderma Lucidum （China）. Rabbit anti-somatostatin antibodies and secondary antibodies were purchased from Wuhan Boster Company （China）. Neuropeptide Y radioimmunoassay kit was purchased from Beijing Furui Biotechnology Company （China）. METHODS： Thirty rats were randomly divided into three groups： a control group, an epilepsy model group and a Ganoderma lucidum spore-treated group. Each group contained 10 animals. Rats in the epilepsy model group were treated with intraperitoneal injections of PTZ and gastric perfusion of physiologic saline. In the Ganoderma lucidum spore-treated group, intraperitoneal injection of PTZ and gastric perfusion of Ganoderma lucidum spore powder were administered. The blank control group was only administered with the physiological saline by intraperitoneal injection and gastric perfusion. MAIN OUTCOME MEASURES： Immunohistochemical staining and radioimmunoassay methods were used to observe the changes of somatostatin and neuropeptide Y content in brain tissue of epileptic rats, as well as the morphology of neurons. RESULTS： All 30 rats were involved in the result analysis, without any loss. The number of somatostatin immunoreacted positive cells in the cerebral cortex and hippocampus was significantly increased in the epilepsy model group compared to the blank control group （P 〈 0.01）. The number of somatostatin immunoreacted positive cells in cerebral cortex and hippocampus was significantly decreased in the Ganoderma lucidum spore-treated group compared to the epilepsy model group （P 〈 0.01）. The contents of neuropeptide Y in cerebral cortex and hippocampus were significantly increased in the epilepsy model group compared to the blank control group （P 〈 0.01）. The contents of neuropeptide Y in the cerebral cortex and hippocampus were significantly decreased in the Ganoderma lucidum spore-treated group compared to the epilepsy model group （P 〈 0.05）. The epilepsy seizures in the Ganoderma lucidum spore-treated group were obviously reduced compared to the epilepsy model group. CONCLUSION： Ganoderma lucidum spore powder was able to reduce the somatostatin and neuropeptide Y content in the cerebral cortex and hippocampus effectively, so as to achieve an anti-epileptic function and protect neurons from being damaged.

The effect of traditional Chinese medicine──Tian Gui Recipeon obesity and anovulation in androgen-sterilized rats

Objective: A traditional Chinese medicine Tian Gui Recipe (TGR) has been used to effectively treat clomiphene resistant anovulatory disease and obesity, especially in polycystic ovary syndrome (PCOS) cases with hyperinsulinemia. The effect of TGR on obesity and anovulation was investigated in androgen-sterilized rats (ASR). Methods: Female SD rats at the age of 9 days were divided into 3 groups. Group ASR (n=15): anovulation was demonstrated at the age of 70 days by vaginal smear in rats while 1. 25 mg of testosterone propionate was injected subcutaneously on its 9th neonatal day. Group A+H (n = 25): TGR were administered to ASR at the age of 80 days for 3 weeks. Rats with regular estrous cycle and ovulation after herbal treatment were included in this group. Group C (n = 15): normal ovulated rats were recruited. Around the age of 112 days or on proestrous day, all rats were sacrificed under anesthesia. Serum leptin, testosterone (T), estrogen (E2), follicular stimulating hormone (FSH), luteinizing hormone (LH) levels were measured with radioimmunoassay (RIA). Double immunofluorescent staining combined with confocal laser scanning microscope and dual in situ hybridization were carried out on sections through areas of arcuate nucleus (ARC) to determine whether estrogen receptor (ER) immunoreactivity (IR) or long form of leptin receptor (OB-Rb) mRNA were expressed in neuropeptide Y (NPY) immuno-and mRNA-containing neurons, and its relationship to proopiomelanocortin (POMC) mRNA-containing neurons. Immunohistochemistry and in situ hybridization were used to observe the levels of ER, NPY, gonadotrophin releasing hormone (GnRH) and gene expression levels on NPY, OB-Rb, POMC. Meanwhile, the criteria of energy state, including daily food intake, retroperitoneal fat depot pad and body weight, were measured and evaluated. Values of immunohistochemistry and in situ hybridization were expressed in mean optic density (MOD). Results: Seventeen out of the 25 rats (68%) in Group A+H were ovulated after herbal treatment. ASR characterized with significantly high metabolic rate, energy imbalance and obesity (P<0. 01, P<0. 01, P<0. 01). The mean serum leptin, T, E2 levels of group ASR were significantly higher than those of Group C and Group A+H (P< 0. 01,P<0. 01 ), while FSH, LH levels were lower (P<0. 01, P<0. 01 ). ERs were proved to be distributing in NPY-containing neurons, OB-Rb coexpressed in NPY-syn- thesizing neurons, and both NPY and POMC mRNA expressing neurons overlapped in ARC. Compared to Group C, levels of NPY mRNA and NPY, POMC mRNA expressions were increased (P<0. 01, P<0. 01, P<0. 01 ), OB-Rb mRNA, ER and GnRH immunoreactive expression were decreased significantly in the hypothalamus of ASR (P<0. 01, P<0. 01, P<0. 01 ). These dramatic neuroendocrine changes became normal in ovulated ASR after the herbal treatment (all P>0. 05). Conclusion: The elevated peripheral E2 caused by high T and leptin levels in ASR may down-regulate their corresponding receptors oriented on hypothalamic NPY- containing neurons respectively, therefore challenge the NPY mRNA and NPY, POMC mRNA overexpressions. The overexpression, of NPY, POMC gene transcription and translation stimulate food intake, promote the deposit of adipocyte tissue, and inhibit GnRH expression and GnRH/FSH, LH release, which contribute to the occurrence of obesity and anovulation in ASR. TGR may reverse these abnormal neuroendocrine cascades by lowering the levels of T, E2 and leptin.

Anti-epileptic effects of neuropeptide Y gene transfection into the rat brain

Neuropeptide Y gene transfection into normal rat brain tissue can provide gene overexpression, which can attenuate the severity of kainic acid-induced seizures. In this study, a recombinant adeno-associated virus carrying the neuropeptide Y gene was transfected into brain tissue of rats with kainic acid-induced epilepsy through stereotactic methods. Following these transfections, we verified overexpression of the neuropeptide Y gene in the epileptic brain. Electroencephalograms showed that seizure severity was significantly inhibited and seizure latency was significantly prolonged up to 4 weeks after gene transfection. Moreover, quantitative fluorescent PCR and western blot assays revealed that the mRNA and protein expression of the N-methyI-D-aspartate receptor subunits NR1, NR2A, and NR2B was inhibited in the hippocampus of epileptic rats. These findings indicate that neuropeptide Y may inhibit seizures via down-regulation of the functional expression of N-methyI-D-aspartate receptors.

Neuropeptide Y gene transfection inhibits post-epileptic hippocampal synaptic reconstruction

Exogenous neuropeptide Y has antiepileptic effects; however, the underlying mechanism and optimal administration method for neuropeptide Y are still unresolved. Previous studies have used intracerebroventricular injection of neuropeptide Y into animal models of epilepsy. In this study, a recombinant adeno-associated virus expression vector carrying the neuropeptide Y gene was injected into the lateral ventricle of rats, while the ipsilateral hippocampus was injected with kainic acid to establish the epileptic model. After transfection of neuropeptide Y gene, mossy fiber sprouting in the hippocampal CA3 region of epileptic rats was significantly suppressed, hippocampal synaptophysin （p38） mRNA and protein expression were inhibited, and epileptic seizures were reduced. These experimental findings indicate that a recombinant adeno-associated virus expression vector carrying the neuropeptide Y gene reduces mossy fiber sprouting and inhibits abnormal synaptophysin expression, thereby suppressing post-epileptic synaptic reconstruction.

Metformin inhibits food intake and neuropeptide Y gene expression in the hypothalamus

Metformin may reduce food intake and body weight, but the anorexigenic effects of metformin are still poorly understood. In this study, Sprague-Dawley rats were administered a single intracere- broventricular dose of metformin and compound C, in a broader attempt to investigate the regula- tory effects of metformin on food intake and to explore the possible mechanism. Results showed that central administration of metformin significantly reduced food intake and body weight gain, par- ticularly after 4 hours. A reduction of neuropeptide Y expression and induction of AMP-activated protein kinase phosphorylation in the hypothalamus were also observed 4 hours after metformin administration, which could be reversed by compound C, a commonly-used antagonist of AMP-activated protein kinase. Furthermore, metformin also improved lipid metabolism by reducing plasma low-density lipoprotein. Our findings suggest that under normal physiological conditions, central regulation of appetite by metformin is related to a decrease in neuropeptide Y gene expres- sion, and that the activation of AMP-activated protein kinase may simply be a response to the anorexigenic effect of metformin.

Identification of differentially expressed genes in ulcerative colitis and verification in a colitis mouse model by bioinformatics analyses

BACKGROUND Ulcerative colitis(UC)is an inflammatory bowel disease that is difficult to diagnose and treat.To date,the degree of inflammation in patients with UC has mainly been determined by measuring the levels of nonspecific indicators,such as C-reactive protein and the erythrocyte sedimentation rate,but these indicators have an unsatisfactory specificity.In this study,we performed bioinformatics analysis using data from the National Center for Biotechnology Information-Gene Expression Omnibus(NCBI-GEO)databases and verified the selected core genes in a mouse model of dextran sulfate sodium(DSS)-induced colitis.AIM To identify UC-related differentially expressed genes(DEGs)using a bioinformatics analysis and verify them in vivo and to identify novel biomarkers and the underlying mechanisms of UC.METHODS Two microarray datasets from the NCBI-GEO database were used,and DEGs between patients with UC and healthy controls were analyzed using GEO2R and Venn diagrams.We annotated these genes based on their functions and signaling pathways,and then protein-protein interactions(PPIs)were identified using the Search Tool for the Retrieval of Interacting Genes.The data were further analyzed with Cytoscape software and the Molecular Complex Detection(MCODE)app.The core genes were selected and a Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis was performed.Finally,colitis model mice were established by administering DSS,and the top three core genes were verified in colitis mice using real-time polymerase chain reaction(PCR).RESULTS One hundred and seventy-seven DEGs,118 upregulated and 59 downregulated,were initially identified from the GEO2R analysis and predominantly participated in inflammation-related pathways.Seven clusters with close interactions in UC formed:Seventeen core genes were upregulated[C-X-C motif chemokine ligand 13(CXCL13),C-X-C motif chemokine receptor 2(CXCR2),CXCL9,CXCL5,C-C motif chemokine ligand 18,interleukin 1 beta,matrix metallopeptidase 9,CXCL3,formyl peptide receptor 1,complement component 3,CXCL8,CXCL1,CXCL10,CXCL2,CXCL6,CXCL11 and hydroxycarboxylic acid receptor 3]and one was downregulated[neuropeptide Y receptor Y1(NYP1R)]in the top cluster according to the PPI and MCODE analyses.These genes were substantially enriched in the cytokinecytokine receptor interaction and chemokine signaling pathways.The top three core genes(CXCL13,NYP1R,and CXCR2)were selected and verified in a mouse model of colitis using real-time PCR Increased expression was observed compared with the control mice,but only CXCR2 expression was significantly different.CONCLUSION Core DEGs identified in UC are related to inflammation and immunity inflammation,indicating that these reactions are core features of the pathogenesis of UC.CXCR2 may reflect the degree of inflammation in patients with UC.

Neuropeptide Y protects cerebral cortical neurons by regulating microglial immune function

Neuropeptide Y has been shown to inhibit the immunological activity of reactive microglia in the rat cerebral cortex, to reduce N-methyl-D-aspartate current（INMDA） in cortical neurons, and protect neurons. In this study, after primary cultured microglia from the cerebral cortex of rats were treated with lipopolysaccharide, interleukin-1β and tumor necrosis factor-α levels in the cell culture medium increased, and mRNA expression of these cytokines also increased. After primary cultured cortical neurons were incubated with the lipopolysaccharide-treated microglial conditioned medium, peak INMDA in neurons increased. These effects of lipopolysaccharide were suppressed by neuropeptide Y. After addition of the neuropeptide Y Y1 receptor antagonist BIBP3226, the effects of neuropeptide Y completely disappeared. These results suggest that neuropeptide Y prevents excessive production of interleukin-1β and tumor necrosis factor-α by inhibiting microglial reactivity. This reduces INMDA in rat cortical neurons, preventing excitotoxicity, thereby protecting neurons.

Activities of autonomic neurotransmitters in meibomian gland tissues are associated with menopausal dry eye

The secretory activities of meibomian glands are regulated by the autonomic nervous system, The change in density and activity of autonomic nerves in meibomian glands during menopause play an important role in the pathogenesis of dry eye. In view of this, we established a dry eye rat model by removing the bilateral ovaries. We used neuropeptide Y and vasoactive intestinal polypeptide as markers of autonomic neurotransmitters. Our results showed that the concentration of estradiol in serum significantly decreased, the density of neuropeptide Y immunoreactivity in nerve fibers significantly increased, the density of vasoactive intestinal polypeptide immunoreactivity in nerve fibers significantly decreased, and the ratio of vasoactive intestinal polypeptide/neuropeptide Y positive staining significantly decreased. These results suggest that a decrease in ovary activity may lead to autonomic nervous system dysfunction, thereby affecting the secretory activity of the meibomian gland, which participates in sexual hormone imbalance-induced dry eye.

Effect of Amlodipine on the Growth of Vascular SmoothMuscle Cells of Spontaneously Hypertensive Rats

The effect of anti-hypertensive drug amlodipine on regression of cardiovascular hypertrophy due to hypertension was studied by using cultured smooth muscle cells derived from arteries of spontaneously hypertensive rats (SHR) and measuring [3H]-TdR and [3H]-Leucine binding. 48 h after adding amlodipine.[3H] -TdR binding in arterial smooth muscle cells from SHR in vitro was reduced by 50.5% and [3H]-Leucine binding was reduced by 56. 2% as compared with neuropeptide Y (NPY)-treated group. However, there was no significant change in cell number. The results showed that amlodipine could effectively inhibit increase of DNA and protein synthesis of vascular smooth muscle cell (VSMC) due to NPY. It indicates that amlodipine is of great significance on regression of genesis and development of cardiovascular hypertrophy due to hypertension.