1.Bile acids regulate anorexigenic neuropeptide through p-STAT3-SOCS3 signaling in mouse hypothalamic cells.
Chunxiu CHEN ; Yong ZHOU ; Rongfeng HUANG ; Miaoran WANG ; Yue LI ; Jibin LI
Journal of Zhejiang University. Medical sciences 2020;40(7):1001-1007
OBJECTIVE:
To explore the effects of taurolithocholic acid (tLCA) and chenodeoxycholic acid (CDCA) on the expression of aorexigenic neuropeptide in mouse hypothalamus GT1-7 cells.
METHODS:
Mouse hypothalamic GT1-7 cells were treated with culture medium containing 10% FBS (control group, =3) or with 10 nmol/L, 100 nmol/L, 1 μmol/L and 10 μmol/L tLCA (tLCA group, =3) or CDCA (CDCA group, =3) for 12, 24 or 48 h. Real-time PCR was performed to determine the expression levels of proopiomelanocortin (POMC) mRNA in the cells, and the production levels of α-melanocyte-stimulating hormone (α-MSH) were assessed using an ELISA kit. Signal transduction and activator of transcription 3 phosphorylation (p-STAT3), threonine kinase phosphorylation (p-AKT), suppressor of cytokine signaling 3 (SOCS3), G protein-coupled bile acid receptor-1 (TGR5) and farnesoid X receptor (FXR) protein were detected by Western blotting.
RESULTS:
Western blotting results showed that mouse hypothalamic GT1-7 cells expressed two bile acid receptors, TGR5 and FXR, whose expressions were regulated by bile acids. Real-time PCR showed that the expression of POMC mRNA was significantly increased in the cells after treatment with 10 μmol/L tLCA or CDCA for 24 h. POMC-derived anorexigenic peptide α-MSH increased significantly in GT1-7 cells after treatment with 10 μmol/L tLCA or CDCA for 24 h. Treatment of the cells with tLCA or CDCA significantly increased the expressions of intracellular signaling proteins including p-STAT3, p-AKT and SOCS3.
CONCLUSIONS
Mouse hypothalamic GT1-7 cells express bile acid receptors TGR5 and FXR. Bile acids tLCA or CDCA can promote the expression of POMC mRNA and increase the production of the anorexigenic peptide α-MSH. The intracellular signaling proteins p-AKT, p-STAT3 and SOCS3 are likely involved in bile acid-induced anorexigenic peptide production.
Animals
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Cell Line
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Chenodeoxycholic Acid
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pharmacology
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Gene Expression Regulation
;
drug effects
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Hypothalamus
;
cytology
;
Mice
;
Neuropeptides
;
genetics
;
metabolism
;
Pro-Opiomelanocortin
;
genetics
;
RNA, Messenger
;
genetics
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STAT3 Transcription Factor
;
metabolism
;
Signal Transduction
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drug effects
;
Suppressor of Cytokine Signaling 3 Protein
;
metabolism
;
Taurolithocholic Acid
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pharmacology
;
alpha-MSH
;
genetics
2.Puerarin attenuates angiotensin II-induced cardiac fibroblast proliferation via the promotion of catalase activity and the inhibition of hydrogen peroxide-dependent Rac-1 activation.
Gang CHEN ; Shi-Fen PAN ; Xiang-Li CUI ; Li-Hong LIU
Chinese Journal of Natural Medicines (English Ed.) 2018;16(1):41-52
The aims of the present study were to evaluate the effects of puerarin on angiotensin II-induced cardiac fibroblast proliferation and to explore the molecular mechanisms of action. Considering the role of HO in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation, we hypothesized that modulating catalase activity would be a potential target in regulating the redox-sensitive pathways. Our results showed that the activation of Rac1 was dependent on the levels of intracellular HO. Puerarin blocked the phosphorylation of extracellular regulated protein kinases (ERK)1/2, abolished activator protein (AP)-1 binding activity, and eventually attenuated cardiac fibroblast proliferation through the inhibition of HO-dependent Rac1 activation. Further studies revealed that angiotensin II treatment resulted in decreased catalase protein expression and enzyme activity, which was disrupted by puerarin via the upregulation of catalase protein expression at the transcriptional level and the prolonged protein degradation. These findings indicated that the anti-proliferation mechanism of puerarin was mainly through blocking angiontensin II-triggered downregulation of catalase expression and HO-dependent Rac1 activation.
Angiotensin II
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pharmacology
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Angiotensin II Type 1 Receptor Blockers
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pharmacology
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Animals
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Animals, Newborn
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Catalase
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genetics
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metabolism
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Cell Proliferation
;
drug effects
;
Cells, Cultured
;
Extracellular Signal-Regulated MAP Kinases
;
antagonists & inhibitors
;
metabolism
;
Fibroblasts
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Gene Expression Regulation
;
drug effects
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Heart
;
drug effects
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Hydrogen Peroxide
;
metabolism
;
pharmacology
;
Isoflavones
;
pharmacology
;
Mice
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Myocardium
;
cytology
;
enzymology
;
metabolism
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NADPH Oxidases
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antagonists & inhibitors
;
metabolism
;
Neuropeptides
;
metabolism
;
Signal Transduction
;
drug effects
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Transcription Factor AP-1
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antagonists & inhibitors
;
metabolism
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Transcriptional Activation
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drug effects
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rac1 GTP-Binding Protein
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metabolism
3.Role of Rheb in Human Acute Myeloid Leukemia.
Xiao-Min WANG ; Qiao-Zhu XU ; Ya-Nan GAO ; Juan GAO ; Ming-Hao LI ; Wan-Zhu YANG ; Jiang-Xiang WANG ; Wei-Ping YUAN
Journal of Experimental Hematology 2016;24(3):662-666
OBJECTIVETo investigate the role of Rheb (mTOR activator) in AML development by measuring Rheb expression in bone marrow of adult AML patients and in AML cell line HL-60.
METHODSReal-time PCR assay was used to measure the Rheb mRNA expression in 27 AML patients and 29 ITP patients as control. The relationship between Rheb mRNA expression and age, AML subtype, fusion gene, splenomegaly, hepatomegaly and survival of AML patients was analyzed and compared. In addition, HL-60 cell line over-expressing Rheb was established, and the HL-60 cells and HL-60 cells with overexpression of Rheb were treated with Ara-C of different concentrations, the proliferation level was detected by CCK-8 method, and the IC50 was calculated.
RESULTSThe mRNA level of Rheb in AML patients was similar to that in ITP patients (control). Interestingly, higher expression of Rheb was associated with better survival and was sensitive to Ara-C treatment. However, the expression level of Rheb was not associated with age, AML subtype, fusion gene, and hepatomegaly of patients. Lower expression level of Rheb was associated with splenomegaly. In vitro analysis of HL-60 line indicated that overexpression of Rheb could increased the cell sensitivity to Ara-C treatment (IC50=0.54 µmol/L) and caused HL-60 cell apoptosis.
CONCLUSIONThe lower Rheb expression is a poor prognostic indicator for AML patients, which is associated with AML splenomegaly, the patients and HL-60 cells with low expression of Rheb are insensitive to Ara-C treatment.
Adult ; Apoptosis ; Bone Marrow ; metabolism ; Cytarabine ; pharmacology ; HL-60 Cells ; Humans ; Leukemia, Myeloid, Acute ; genetics ; metabolism ; pathology ; Monomeric GTP-Binding Proteins ; genetics ; metabolism ; Neuropeptides ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Ras Homolog Enriched in Brain Protein ; Real-Time Polymerase Chain Reaction ; Spleen ; pathology
4.Increased orexin expression promotes sleep/wake disturbances in the SOD1-G93A mouse model of amyotrophic lateral sclerosis.
Rong LIU ; Zhao-Fu SHENG ; Bing CAI ; Yong-He ZHANG ; Dong-Sheng FAN
Chinese Medical Journal 2015;128(2):239-244
BACKGROUNDSleep/wake disturbances in patients with amyotrophic lateral sclerosis (ALS) are well-documented, however, no animal or mechanistic studies on these disturbances exist. Orexin is a crucial neurotransmitter in promoting wakefulness in sleep/wake regulation, and may play an important role in sleep disturbances in ALS. In this study, we used SOD1-G93A transgenic mice as an ALS mouse model to investigate the sleep/wake disturbances and their possible mechanisms in ALS.
METHODSElectroencephalogram/electromyogram recordings were performed in SOD1-G93A transgenic mice and their littermate control mice at the ages of 90 and 120 days, and the samples obtained from these groups were subjected to quantitative reverse transcriptase-polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay.
RESULTSFor the first time in SOD1-G93A transgenic mice, we observed significantly increased wakefulness, reduced sleep time, and up-regulated orexins (prepro-orexin, orexin A and B) at both 90 and 120 days. Correlation analysis confirmed moderate to high correlations between sleep/wake time (total sleep time, wakefulness time, rapid eye movement [REM] sleep time, non-REM sleep time, and deep sleep time) and increase in orexins (prepro-orexin, orexin A and B).
CONCLUSIONSleep/wake disturbances occur before disease onset in this ALS mouse model. Increased orexins may promote wakefulness and result in these disturbances before and after disease onset, thus making them potential therapeutic targets for amelioration of sleep disturbances in ALS. Further studies are required to elucidate the underlying mechanisms in the future.
Amyotrophic Lateral Sclerosis ; genetics ; metabolism ; Animals ; Female ; Intracellular Signaling Peptides and Proteins ; genetics ; metabolism ; Male ; Mice ; Mice, Transgenic ; Neuropeptides ; genetics ; metabolism ; Orexins ; Reverse Transcriptase Polymerase Chain Reaction ; Sleep ; physiology ; Superoxide Dismutase ; genetics ; metabolism ; Superoxide Dismutase-1 ; Wakefulness ; physiology
5.MicroRNA-29a modulates axon branching by targeting doublecortin in primary neurons.
Hanqin LI ; Susu MAO ; Haitao WANG ; Ke ZEN ; Chenyu ZHANG ; Liang LI
Protein & Cell 2014;5(2):160-169
MicroRNAs (miRNAs) are endogenously expressed small, non-coding transcripts that regulate protein expression. Substantial evidences suggest that miRNAs are enriched in central nervous system, where they are hypothesized to play pivotal roles during neural development. In the present study, we analyzed miRNAs expression in mice cerebral cortex and hippocampus at different developmental stages and found miR-29a increased dramatically at postnatal stages. In addition, we provided strong evidences that miR-29a is enriched in mature neurons both in vitro and in vivo. Further investigation demonstrated that the activation of glutamate receptors induced endogenous miR-29a level in primary neurons. Moreover, we showed that miR-29a directly regulated its target protein Doublecortin (DCX) expression, which further modulated axon branching in primary culture. Together, our results suggested that miR-29a play an important role in neuronal development of mice cerebrum.
Animals
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Axons
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metabolism
;
physiology
;
Hippocampus
;
growth & development
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metabolism
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Mice
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MicroRNAs
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genetics
;
metabolism
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Microtubule-Associated Proteins
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genetics
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Neurogenesis
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Neurons
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metabolism
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Neuropeptides
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genetics
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Primary Cell Culture
6.Synergistic anti-inflammatory effect of Radix Platycodon in combination with herbs for cleaning-heat and detoxification and its mechanism.
Yu-Hang LI ; Feng-Jie ZHENG ; Ying HUANG ; Xiang-Gen ZHONG ; Ming-Zhang GUO
Chinese journal of integrative medicine 2013;19(1):29-35
OBJECTIVETo investigate the synergistic anti-inflammatory effect of Radix Platycodon in combination with herbs for cleaning-heat and detoxification and its mechanism for Fel-targeting.
METHODSForty Wistar rats were randomly divided into five groups (8 per group): the sham-operated group, model group, Radix Platycodon group, Flos Lonicera and Fructus Forsythia (LF) group, and Radix Platycodon, Flos Lonicera and Fructus Forsythia combination (PLF) group, using a random number table. A rat chronic obstructive pulmonary disease (COPD) model was established by passive smoking and intratracheal instillation of lipopolysaccharide (LPS). The treatments started from the 15th day of passive smoking for a total duration of 14 days. At the end of the treatment, changes in the following measurements were determined: lung histopathology, inflammatory cytokines including tumor necrosis factor α (TNF-α), transforming growth factor β (TGF-β) and interleukin IL-1β (IL-1β) in bronchoalveolar lavage fluid (BALF), and mRNA expression of endogenous active substance intestinal trefoil factor 3 (TFF3) in the lung tissue.
RESULTSLight microscopy showed that compared with the sham-operated group, rats in the COPD model group had disrupted alveolar structure, collapsed local alveoli, significantly widened or even fused alveolar septa, and massive infiltration of inflammatory cells in the alveolar wall and interstitium. In addition, significant bronchial epithelium hyperplasia, partially shed epithelia, and marked inflammatory cell infiltration in the bronchial wall and its surrounding tissues were noticed. Electron microscopy showed that rats in the model group had degeneration of alveolar type II epithelial cell; reduction, breakage or even loss of cell surface microvilli; swollen mitochondria with disappearing cristae and vacuole-like structure; and, increased secondary lysosomes in alveolar macrophages. The TNF-α, TGF-β and IL-1β levels and white blood cell (WBC) count in BALF were significantly increased (P < 0.01 or P < 0.05) and TFF3 mRNA expression in the lung tissue was significantly reduced (P < 0.01). After treatment, the pathological morphology of lung injury was less severe in all three treatment groups. In addition, TGF-β and IL-1β and WBC count in BALF were decreased (P < 0.01 or P < 0.05), and TFF3 mRNA expression in the lung tissue was significantly increased in the PLF group (P < 0.01). Compared with the LF group, the IL-1β in BALF was significantly decreased P < 0.05), and TFF3 mRNA expression was significantly increased (P < 0.05) in the PLF group.
CONCLUSIONSRadix Platycodon synergizes with herbs for cleaning-heat and detoxification in reducing inflammatory injury in a rat model of COPD. The synergistic anti-inflammatory effect is reflected in the improvement in pathological changes and in the reduction of IL-1β levels in BALF. The mechanism of such synergistic action may be related to its effect on maintaining the TFF3 mRNA expression and Fel-targeting function.
Animals ; Bronchoalveolar Lavage Fluid ; chemistry ; cytology ; Disease Models, Animal ; Drug Synergism ; Drug Therapy, Combination ; Drugs, Chinese Herbal ; therapeutic use ; Immunohistochemistry ; Lung ; drug effects ; pathology ; Male ; Microscopy, Electron ; Neuropeptides ; genetics ; metabolism ; Phytotherapy ; methods ; Plant Preparations ; therapeutic use ; Platycodon ; Polymerase Chain Reaction ; methods ; Pulmonary Disease, Chronic Obstructive ; drug therapy ; pathology ; RNA, Messenger ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Sensitivity and Specificity ; Trefoil Factor-3
7.Apoptosis signal-regulating kinase 1 (ASK1) is linked to neural stem cell differentiation after ischemic brain injury.
Juhyun SONG ; Kyoung Joo CHO ; So Yeong CHEON ; Sa Hyun KIM ; Kyung Ah PARK ; Won Taek LEE ; Jong Eun LEE
Experimental & Molecular Medicine 2013;45(12):e69-
Neural stem cells (NSCs) have been suggested as a groundbreaking solution for stroke patients because they have the potential for self-renewal and differentiation into neurons. The differentiation of NSCs into neurons is integral for increasing the therapeutic efficiency of NSCs during inflammation. Apoptosis signal-regulating kinase 1 (ASK1) is preferentially activated by oxidative stress and inflammation, which is the fundamental pathology of brain damage in stroke. ASK1 may be involved in the early inflammation response after stroke and may be related to the differentiation of NSCs because of the relationship between ASK1 and the p38 mitogen-activated protein kinase pathway. Therefore, we investigated whether ASK1 is linked to the differentiation of NSCs under the context of inflammation. On the basis of the results of a microarray analysis, we performed the following experiments: western blot analysis to confirm ASK1, DCX, MAP2, phospho-p38 expression; fluorescence-activated cell sorting assay to estimate cell death; and immunocytochemistry to visualize and confirm the differentiation of cells in brain tissue. Neurosphere size and cell survival were highly maintained in ASK1-suppressed, lipopolysaccharide (LPS)-treated brains compared with only LPS-treated brains. The number of positive cells for MAP2, a neuronal marker, was lower in the ASK1-suppressed group than in the control group. According to our microarray data, phospho-p38 expression was inversely linked to ASK1 suppression, and our immunohistochemistry data showed that slight upregulation of ASK1 by LPS promoted the differentiation of endogenous, neuronal stem cells into neurons, but highly increased ASK1 levels after cerebral ischemic damage led to high levels of cell death. We conclude that ASK1 is regulated in response to the early inflammation phase and regulates the differentiation of NSCs after inflammatory-inducing events, such as ischemic stroke.
Animals
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Cell Death
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Infarction, Middle Cerebral Artery/*metabolism
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Lipopolysaccharides/pharmacology
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MAP Kinase Kinase Kinase 5/genetics/*metabolism
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Male
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Mice
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Mice, Inbred C57BL
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Microtubule-Associated Proteins/genetics/metabolism
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Neural Stem Cells/cytology/drug effects/*metabolism
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*Neurogenesis
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Neuropeptides/genetics/metabolism
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p38 Mitogen-Activated Protein Kinases/genetics/metabolism
8.Construction of recombinant lentiviral vectors containing Rheb gene and its mutant Rheb'D60K gene and their expression in human liver cancer cells.
Ke-He CHEN ; Bo LIANG ; Zhen-Hong ZOU ; Ze-Long HAN ; Jin-Fei PAN ; An-Ling LIU
Journal of Southern Medical University 2012;32(3):341-344
OBJECTIVETo construct recombinant lentiviral vectors carrying Rheb gene and its mutant Rheb'D60K gene, and examine their expression in human liver cancer cells.
METHODSRheb gene was amplified by PCR to construct the recombinant plasmid LV31-Rheb-WT and LV31-Rheb-D60K. HEK-293 FT cells were contransfected with the recombinant lentiviral vector together with a lentiviral package plasmid to produce the lentiviral particles. The expression of PS6 protein was detected in the lentivirus-infected MCF-7 cells. The apoptosis of SK-HEP-1 cells transfected with LV31-Rheb-WT or LV31-Rheb-D60K was observed.
RESULTSThe recombinant LV31-Rheb-WT and LV31-Rheb-D60K vectors were confirmed by PCR and DNA sequencing. Western blotting showed that PS6 protein expression was increased in LV31-Rheb-WT-transfected cells while decreased in LV31-Rheb-D60K-transfected cells. LV31-Rheb-D60K-transfected SK-HEP-1 cells showed more obvious apoptosis after starvation than LV31-Rheb-WT-transfected cells.
CONCLUSIONLentiviral vectors carrying Rheb gene and its mutant has been successfully constructed, which can be useful in further investigation of the role of Rheb gene in cancer cells.
Apoptosis ; genetics ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Genetic Vectors ; genetics ; HEK293 Cells ; Humans ; Lentivirus ; genetics ; metabolism ; Liver Neoplasms ; metabolism ; pathology ; MCF-7 Cells ; Monomeric GTP-Binding Proteins ; biosynthesis ; genetics ; Mutant Proteins ; genetics ; Neuropeptides ; biosynthesis ; genetics ; Ras Homolog Enriched in Brain Protein ; Recombinant Proteins ; biosynthesis ; genetics ; Transfection
9.Expanding neurotransmitters in the hypothalamic neurocircuitry for energy balance regulation.
Protein & Cell 2011;2(10):800-813
The current epidemic of obesity and its associated metabolic syndromes impose unprecedented challenges to our society. Despite intensive research on obesity pathogenesis, an effective therapeutic strategy to treat and cure obesity is still lacking. Exciting studies in last decades have established the importance of the leptin neural pathway in the hypothalamus in the regulation of body weight homeostasis. Important hypothalamic neuropeptides have been identified as critical neurotransmitters from leptin-sensitive neurons to mediate leptin action. Recent research advance has significantly expanded the list of neurotransmitters involved in body weight-regulating neural pathways, including fast-acting neurotransmitters, gamma-aminobutyric acid (GABA) and glutamate. Given the limited knowledge on the leptin neural pathway for body weight homeostasis, understanding the function of neurotransmitters released from key neurons for energy balance regulation is essential for delineating leptin neural pathway and eventually for designing effective therapeutic drugs against the obesity epidemic.
Animals
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Energy Metabolism
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Gene Expression
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Humans
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Hunger
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Hypothalamus
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metabolism
;
physiology
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Leptin
;
metabolism
;
physiology
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Neural Pathways
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metabolism
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Neuropeptides
;
genetics
;
metabolism
;
Obesity
;
metabolism
10.Soy isoflavone and its effect to regulate hypothalamus and peripheral orexigenic gene expression in ovariectomized rats fed on a high-fat diet.
Yun-Bo ZHANG ; Yang ZHANG ; Li-Na LI ; Xin-Yu ZHAO ; Xiao-Lin NA
Biomedical and Environmental Sciences 2010;23(1):68-75
OBJECTIVETo explore the effect of soy isoflavone on obesity in the light of hypothalamus and peripheral orexigenic gene regulation.
METHODSFifty-four female rats were randomly assigned to 6 groups: one sham-operated group (SHAM), one ovariectomized (OVX) control group, three OVX groups fed with 400 ppm (L-SI), 1200 ppm (M-SI) and 3600 ppm (H-SI) isoflavone respectively, and one OVX group receiving 0.45 ppm diethylstilbestrol (EC). All rats were allowed to take high-fat diet for 4 weeks. Some neuropeptides were measured by RT-PCR. These neuropeptides included NPY, pro-opiomelanocortin (POMC), cocaine and amphetamine regulated transcript (CART), orexin, melanin-concentrating hormone (MCH), melanin-concentrating hormone precursor (P-MCH), ghrelin, and leptin.
RESULTSCompared with the OVX control group, the body weight and food intake in the H-SI group were reduced significantly and there was a significant dose-dependent manner in the 3 isoflavone groups. The results of RT-PCR showed that the NPY level in the 3 isoflavone groups was significantly increased and the POMC/CART gene expression decreased significantly in rats' hypothalamus compared with that in the OVX control group. However, the expression of orexin, MCH and P-MCH had no change. The peripheral grelin mRNA expression was higher in the 3 isoflavone groups, while leptin gene expression in the fat was not consistent.
CONCLUSIONSThis research showed that isoflavone could prevent obesity induced by high-fat diet and ovariectomy through regulating hypothalamus and peripheral orexigenic gene expressions associated with food intake.
Animals ; Dietary Fats ; pharmacology ; Feeding Behavior ; drug effects ; physiology ; Female ; Gene Expression Regulation ; drug effects ; Hypothalamus ; Isoflavones ; chemistry ; pharmacology ; Neuropeptides ; genetics ; metabolism ; Obesity ; Ovariectomy ; RNA, Messenger ; genetics ; metabolism ; Rats ; Soybeans ; chemistry

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