ABSTRACT
BACKGROUND AND AIMS: Obesity and type 2 diabetes are significant risk factors for atherosclerotic cardiovascular disease (CVD) worldwide, but the underlying pathophysiological links are poorly understood. Neurotensin (NT), a 13-amino-acid hormone peptide, facilitates intestinal fat absorption and contributes to obesity in mice fed a high-fat diet. Elevated levels of pro-NT (a stable NT precursor produced in equimolar amounts relative to NT) are associated with obesity, type 2 diabetes, and CVD in humans. Whether NT is a causative factor in CVD is unknown. METHODS: Nt+/+ and Nt-/- mice were either injected with adeno-associated virus encoding PCSK9 mutants or crossed with Ldlr-/- mice and fed a Western diet. Atherosclerotic plaques were analyzed by en face analysis, Oil Red O and CD68 staining. In humans, we evaluated the association between baseline pro-NT and growth of carotid bulb thickness after 16.4 years. Lipidomic profiles were analyzed. RESULTS: Atherosclerotic plaque formation is attenuated in Nt-deficient mice through mechanisms that are independent of reductions in circulating cholesterol and triglycerides but associated with remodeling of the plasma triglyceride pool. An increasing plasma concentration of pro-NT predicts atherosclerotic events in coronary and cerebral arteries independent of all major traditional risk factors, indicating a strong link between NT and atherosclerosis. This plasma lipid profile analysis confirms the association of pro-NT with remodeling of the plasma triglyceride pool in atherosclerotic events. CONCLUSIONS: Our findings are the first to directly link NT to increased atherosclerosis and indicate the potential role for NT in preventive and therapeutic strategies for CVD.
Subject(s)
Atherosclerosis , Neurotensin , Plaque, Atherosclerotic , Triglycerides , Animals , Female , Humans , Male , Mice , Atherosclerosis/blood , Disease Models, Animal , Fatty Acids/metabolism , Fatty Acids/blood , Mice, Inbred C57BL , Mice, Knockout , Neurotensin/blood , Neurotensin/genetics , Neurotensin/metabolism , Protein Precursors , Receptors, LDL/genetics , Receptors, LDL/deficiency , Risk Factors , Triglycerides/blood , Triglycerides/metabolismABSTRACT
Stress has been considered as a potential trigger for hair loss through the neuroendocrine-hair follicle (HF) axis. Neurotensin (NTS), a neuropeptide, is known to be dysregulated in the inflammatory-associated skin diseases. However, the precise role of NTS in stress-induced hair loss is unclear. To investigate the function and potential mechanisms of NTS in stress-induced hair growth inhibition, we initially detected the expression of neurotensin receptor (Ntsr) and NTS in the skin tissues of stressed mice by RNA-sequencing and ELISA. We found chronic restraint stress (CRS) significantly decreased the expression of both NTS and Ntsr in the skin tissues of mice. Intracutaneous injection of NTS effectively counteracted CRS-induced inhibition of hair growth in mice. Furthermore, NTS regulated a total of 1093 genes expression in human dermal papilla cells (HDPC), with 591 genes being up-regulated and 502 genes being down-regulated. GO analysis showed DNA replication, cell cycle, integral component of plasma membrane and angiogenesis-associated genes were significantly regulated by NTS. KEGG enrichment demonstrated that NTS also regulated genes related to the Hippo signalling pathway, axon guidance, cytokine-cytokine receptor interaction and Wnt signalling pathway in HDPC. Our results not only uncovered the potential effects of NTS on stress-induced hair growth inhibition but also provided an understanding of the mechanisms at the gene transcriptional level.
Subject(s)
Hair , Neurotensin , Animals , Humans , Mice , Alopecia/metabolism , Hair Follicle/metabolism , Neuropeptides/metabolism , Neurotensin/genetics , Neurotensin/metabolism , Neurotensin/pharmacology , Receptors, Neurotensin/genetics , Receptors, Neurotensin/metabolism , Hair/growth & development , Hair/metabolismABSTRACT
Neurotensin (NT) is a small protein implicated in the regulation of energy balance which acts as both a neurotransmitter in the central nervous system and as a gastrointestinal peptide. In the gut, NT is secreted after fat ingestion and promotes the absorption of fatty acids. The circulating levels of its precursor, pro-NT, predicts the presence and development of metabolic and cardiovascular diseases. Despite the extensive knowledge on the dynamic changes that occur to pro-NT = after fat load, the determinants of fasting pro-NT are unknown. The aim of this study was to determine the possible genetic regulation of plasma pro-NT. The NT gene (NTS) was sequenced for potential functional variants, evaluating its entire genomic and potentially regulatory regions, in DNA from 28 individuals, stratified by low and high pro-NT levels. The identified variant differently distributed in the two pro-NT subgroups was genotyped in a cohort of nine hundred and thirty-two overweight/obese children and adolescents. A total of seven sequence variations across the NTS gene, none of them located in coding regions, were identified. The rs2234762 polymorphism, sited in the NTS gene promoter, was statistically more frequent in the lowest pro-NTS level group. Carriers of the rs2234762 variant showed lower pro-NT levels, after adjusting for sex, age, BMI, triglycerides and the Tanner stage. Having NTS rs2234762 predicted less pronounced insulin resistance at the 6.5-year follow-up with OR: 0.46 (0.216-0.983), at the logistic regression analysis adjusted for age, sex and BMI. In conclusion, the NTS rs2234762 gene variant is a determinant of reduced circulating pro-NT levels in overweight and obese children, which predisposes this group to a more favorable metabolic profile and a reduced insulin resistance later in life, independently from metabolic confounders.
Subject(s)
Insulin Resistance , Pediatric Obesity , Adolescent , Humans , Child , Neurotensin/genetics , Neurotensin/metabolism , Insulin Resistance/genetics , Overweight/genetics , Fatty AcidsABSTRACT
CONTEXT: Enteroendocrine N cells secrete neurotensin (NTS). NTS reduces food intake in rodents and may increase insulin release. In humans, postprandial NTS responses increase following Roux-en-Y gastric bypass, associating the hormone with the glucose- and body weight-lowering effects of these procedures. OBJECTIVE: We looked at N cell density and mucosal messenger RNA (mRNA) expression profiles of NTS and NTS receptors in type 2 diabetes (T2D) patients and healthy controls. METHODS: Using double-balloon enteroscopy, 12 patients with T2D and 12 sex-, age-, and body mass index-matched healthy controls had mucosa biopsies taken from the entire length of the small intestine (at 30-cm intervals) and from 7 anatomically well-defined locations in the large intestine. Biopsies were analyzed using immunohistochemistry and mRNA sequencing. RESULTS: N cell density and NTS mRNA expression gradually increased from the duodenum to the ileum, while negligible NTS-positive cells and NTS mRNA expression were observed in the large intestine. NTS receptor 1 and 2 mRNA expression were not detected, but sortilin, a single-pass transmembrane neuropeptide receptor of which NTS also is a ligand, was uniformly expressed in the intestines. Patients with T2D exhibited lower levels of NTS-positive cells and mRNA expression than healthy controls, but this was not statistically significant after adjusting for multiple testing. CONCLUSION: This unique intestinal mapping of N cell density and NTS expression shows increasing levels from the small intestine's proximal to distal end (without differences between patients with T2D and healthy controls), while negligible N-cells and NTS mRNA expression were observed in the large intestine. Sortilin was expressed throughout the intestines in both groups; no NTS receptor 1 or 2 mRNA expression were detected.
Subject(s)
Diabetes Mellitus, Type 2 , Neurotensin , Humans , Neurotensin/genetics , Diabetes Mellitus, Type 2/metabolism , Glucagon-Like Peptide 1/metabolism , Intestines , Proteins , RNA, MessengerABSTRACT
Neurotensin (NT) is a 13-residue endogenous peptide found in mammals, with neurotransmission and hormonal roles in the central nervous system and gastrointestinal tract, respectively. The first residue of NT is a pyroglutamate (pGlu) that makes the expression and purification of large amounts of NT with native modification challenging. Here, we describe a simple and efficient procedure for expression and purification of large amounts of NT based on using the small ubiquitin-like modifier (SUMO) as a fusion partner and subsequent enzymatic conversion of the N-terminal glutamine to pGlu. Yields of 13 mg/L and 8 mg/L of pure peptide were obtained from expression in rich and minimal media, respectively. The method is adaptable to expression and purification of proteins and peptides with pGlu modification in a wide range of eukaryotic and prokaryotic expression hosts.
Subject(s)
Neurotensin , Pyrrolidonecarboxylic Acid , Animals , Neurotensin/genetics , Neurotensin/chemistry , Neurotensin/metabolism , Peptides/chemistry , Glutamine , MammalsABSTRACT
The luteinizing hormone (LH) surge induces paracrine mediators within the ovarian follicle that promote ovulation. The present study explores neurotensin (NTS), a neuropeptide, as a potential ovulatory mediator in the mouse ovary. Ovaries and granulosa cells (GCs) were collected from immature 23-day-old pregnant mare serum gonadotropin primed mice before (0 h) and after administration of human chorionic gonadotropin (hCG; an LH analog) across the periovulatory period (4, 8, 12, and 24 h). In response to hCG, Nts expression rapidly increased 250-fold at 4 h, remained elevated until 8 h, and decreased until 24 h. Expression of Nts receptors for Ntsr1 remained unchanged across the periovulatory period, Ntsr2 was undetectable, whereas Sort1 expression (also called Ntsr3) gradually decreased in both the ovary and GCs after hCG administration. To better understand Nts regulation, inhibitors of the LH/CG signaling pathways were utilized. Our data revealed that hCG regulated Nts expression through the protein kinase A (PKA) and p38 mitogen-activated protein kinase (p38MAPK) signaling pathways. Additionally, epidermal-like-growth factor (EGF) receptor signaling also mediated Nts induction in GCs. To elucidate the role of NTS in the ovulatory process, we used a Nts silencing approach (si-Nts) followed by RNA-sequencing (RNA-seq). RNA-seq analysis of GCs collected after hCG with or without si-Nts identified and qPCR confirmed Ell2, Rsad2, Vps37a, and Smtnl2 as genes downstream of Nts. In summary, these findings demonstrate that hCG induces Nts and that Nts expression is mediated by PKA, p38MAPK, and EGF receptor signaling pathways. Additionally, NTS regulates several novel genes that could potentially impact the ovulatory process.
Subject(s)
Neurotensin , Ovary , Ovulation , Animals , Female , Mice , Chorionic Gonadotropin/pharmacology , Chorionic Gonadotropin/metabolism , Granulosa Cells/metabolism , Horses , Luteinizing Hormone/metabolism , Neurotensin/genetics , Neurotensin/metabolism , Ovarian Follicle/metabolism , Ovary/metabolism , Ovulation/genetics , Ovulation/physiology , Transcriptional Elongation Factors/metabolismABSTRACT
Xenin-25 has a variety of physiological functions in the gastrointestinal tract, including ion transport and motility. Xenin-25 and neurotensin show sequence homology, especially near their C-terminal regions. The sequence similarity between xenin-25 and neurotensin indicates that the effects of xenin-25 is mediated by the neurotensin receptor but some biological actions of xenin-25 are independent. We have previously reported that xenin-25 modulates intestinal ion transport and colonic smooth muscle activity. However, minimal biological domain of xenin-25 to induce ion transport was not clear. To improve the mechanistic understanding of xenin-25 and to gain additional insights into the functions of xenin-25, the present study was designed to determine the minimal biological domain of xenin-25 required for ion transport in the rat ileum using various truncated xenin fragments and analogues in an Ussing chamber system. The present results demonstrate that the minimum biological domain of xenin-25 to induce Cl-/HCO3- secretion in the ileum contains the C-terminal pentapeptide. Furthermore, Arg at position 21 is important to retain the biological activity of xenin-25 and induces Cl-/HCO3- secretion in the rat ileum.
Subject(s)
Anions/metabolism , Ileum/metabolism , Neurotensin/metabolism , Animals , Ileum/drug effects , Male , Neurotensin/analogs & derivatives , Neurotensin/genetics , Neurotensin/pharmacology , Protein Domains , Pyrazoles/pharmacology , Quinolines/pharmacology , Rats, Sprague-Dawley , Receptors, Neurotensin/antagonists & inhibitorsABSTRACT
The lymphatic vasculature plays important roles in the physiology of the organs in which it resides, though a clear mechanistic understanding of how this crosstalk is mediated is lacking. Here, we performed single-cell transcriptional profiling of human and mouse adipose tissue and found that lymphatic endothelial cells highly express neurotensin (NTS/Nts). Nts expression is reduced by cold and norepinephrine in an α-adrenergic-dependent manner, suggesting a role in adipose thermogenesis. Indeed, NTS treatment of brown adipose tissue explants reduced expression of thermogenic genes. Furthermore, adenoviral-mediated overexpression and knockdown or knockout of NTS in vivo reduced and enhanced cold tolerance, respectively, an effect that is mediated by NTSR2 and ERK signaling. Inhibition of NTSR2 promoted energy expenditure and improved metabolic function in obese mice. These data establish a link between adipose tissue lymphatics and adipocytes with potential therapeutic implications.
Subject(s)
Endothelial Cells/metabolism , Lymphatic Vessels/cytology , Neurotensin/physiology , Thermogenesis , Animals , Energy Metabolism/drug effects , Energy Metabolism/genetics , Lymphatic Vessels/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Obese , Neurotensin/genetics , Neurotensin/metabolism , Neurotensin/pharmacology , Signal Transduction/genetics , Thermogenesis/drug effects , Thermogenesis/geneticsABSTRACT
CONTEXT: The peptide neurotensin is implicated in insulin resistance, diabetes mellitus (DM), and cardiovascular disease. OBJECTIVE: We studied the association of neurotensin's stable precursor, pro-neurotensin/neuromedin N (pro-NT/NMN) with incident metabolic syndrome (MetS) and DM. METHODS: We included 3772 participants from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study who completed the baseline exam (2003-2007), the follow-up exam (2013-2016), and had pro-NT/NMN measured by immunoassay. Weighted logistic regression models were fitted to incident DM, incident MetS, and each MetS component, separately, incorporating demographics, metabolic risk factors, homeostasis model of insulin resistance (HOMA-IR), and diet scores. Incident MetS was defined by 3 or more harmonized criteria at follow-up in those with fewer than 3 at baseline. Incident DM was defined by use of hypoglycemic drugs/insulin, fasting glucose 126 mg/dL or greater, or random glucose 200 mg/dL or greater in those without these at baseline. RESULTS: Median (IQR) plasma pro-NT/NMN was 160 pmol/L (118-218 pmol/L). A total of 564 (of 2770 without baseline MetS) participants developed MetS, and 407 (of 3030 without baseline DM) developed DM. Per SD higher log-pro-NT/NMN, the demographic-adjusted odds ratio (OR) and 95% CI of incident MetS was 1.22 (1.11-1.35), 1.16 (1.00-1.35) for incident low high-density lipoprotein (HDL), and 1.25 (1.11-1.40) for incident dysglycemia. The association of pro-NT/NMN with MetS was attenuated in the model adding HOMA-IR (OR per SD log-pro-NT/NMN 1.14; 95% CI, 1.00-1.30). There was no association with incident DM (OR per SD log-pro-NT/NMN 1.06; 95% CI, 0.94-1.19). CONCLUSION: Pro-NT/NMN was associated with MetS and 2 components, dysglycemia and low HDL, likely explained by insulin resistance.
Subject(s)
Diabetes Mellitus/blood , Diabetes Mellitus/epidemiology , Metabolic Syndrome/blood , Metabolic Syndrome/epidemiology , Neurotensin/genetics , Peptide Fragments/genetics , Blood Glucose/analysis , Case-Control Studies , Cohort Studies , Diet , Female , Humans , Hypoglycemic Agents/therapeutic use , Insulin Resistance/genetics , Lipoproteins, HDL/blood , Male , Middle Aged , Neurotensin/blood , Peptide Fragments/blood , Risk Factors , Stroke/epidemiologyABSTRACT
BACKGROUND: Germline BRCA1/2 mutation carriers (gBMC) face increased cancer risks that are modulated via non-genetic lifestyle factors whose underlying molecular mechanisms are unknown. The peptides Neurotensin (NT) and Enkephalin (ENK)-involved in tumorigenesis and obesity-related diseases-are of interest. We wanted to know whether these biomarkers differ between gBMC and women from the general population and what effect a 1-year lifestyle-intervention has in gBMC. METHODS: The stable precursor fragments pro-NT and pro-ENK were measured at study entry (SE), after 3 and 12 months for 68 women from LIBRE-1 (a controlled lifestyle-intervention feasibility trial for gBMC involving structured endurance training and the Mediterranean Diet). The SE values were compared with a cohort of the general population including female subjects with and without previous cancer disease, non-suggestive for hereditary breast and ovarian cancer (OMA-reference). For LIBRE-1, we analysed the association between the intervention-related change in the two biomarkers and certain lifestyle factors. RESULTS: At SE, gBMC had a higher median pro-NT than OMA-reference (in the subgroups with previous cancer 117 vs. 91 pmol/L, p = 0.002). Non-diseased gBMC had lower median pro-ENK levels when compared to the non-diseased reference group. VO2peak and pro-NT 1-year change in LIBRE-1 were inversely correlated (r = - 0.435; CI - 0.653 to - 0.151; p = 0.004). Pro-ENK correlated positively with VO2peak at SE (r = 0.323; CI 0.061-0.544; p = 0.017). Regression analyses showed an inverse association of 1-year changes for pro-NT and Omega-6/Omega-3 (Estimate: - 37.9, p = 0.097/0.080) in multivariate analysis. CONCLUSION: Our results give first indications for lifestyle-related modification particularly of pro-NT in gBMC.
Subject(s)
Breast Neoplasms , Neurotensin , BRCA1 Protein/genetics , Breast Neoplasms/epidemiology , Breast Neoplasms/genetics , Enkephalins/genetics , Female , Germ Cells , Germ-Line Mutation , Humans , Life Style , Mutation , Neurotensin/geneticsABSTRACT
In this study, we aimed to investigate the role of circORC2 in modulating miR-19a and its downstream signalling during the pathogenesis of STC. In this study, three groups of patients, that is healthy control (HC) group, normal transit constipation (NTC) group (N = 42) and slow transit constipation (STC) group, were, respectively, recruited. RT-PCR and Western blot analysis were exploited to investigate the changes in the expression levels of miR-19a and circORC2 in these patients, so as to establish a circORC2/miR-19a signalling pathway. The basic information of the patients showed no significant differences among different patient groups. Compared with the HC group, concentrations of neurotensin (NST) and motilin (MLN) were both significantly reduced in the NTC and STC groups, especially in the STC group. Also, miR-19a level was highest, whereas circORC2 level was lowest in the STC group. Furthermore, circORC2 was validated to sponge the expression of miR-19a, and the transfection of circORC2 reduced the expression of miR-19a. Meanwhile, MLN and NST mRNAs were both targeted by miR-19a, and the transfection of circORC2 dramatically up-regulated the expression of MLN and NST. On the contrary, the transfection of circORC2 siRNA into SMCs and VSMCs exhibited the opposite effect of circORC2. Collectively, the results of this study established a regulatory relationship among circORC2, miR-19a and neurotensin/motilin, which indicated that the overexpression of circORC2 could up-regulate the levels of neurotensin and motilin, thus exerting a beneficial effect during the treatment of STC.
Subject(s)
Biomarkers/metabolism , Constipation/pathology , Gene Expression Regulation , MicroRNAs/genetics , Motilin/metabolism , Neurotensin/metabolism , RNA, Circular/genetics , Aged , Apoptosis , Case-Control Studies , Cell Proliferation , Cells, Cultured , Constipation/genetics , Constipation/metabolism , Female , Humans , Male , Motilin/genetics , Neurotensin/genetics , Origin Recognition Complex , PrognosisABSTRACT
The small peptide neurotensin (Nts) is implicated in myriad processes including analgesia, thermoregulation, reward, arousal, blood pressure, and modulation of feeding and body weight. Alterations in Nts have recently been described in individuals with obesity or eating disorders, suggesting that disrupted Nts signaling may contribute to body weight disturbance. Curiously, Nts mediates seemingly opposing regulation of body weight via different tissues. Peripherally acting Nts promotes fat absorption and weight gain, whereas central Nts signaling suppresses feeding and weight gain. Thus, because Nts is pleiotropic, a location-based approach must be used to understand its contributions to disordered body weight and whether the Nts system might be leveraged to improve metabolic health. Here we review the role of Nts signaling in the brain to understand the sites, receptors, and mechanisms by which Nts can promote behaviors that modify body weight. New techniques permitting site-specific modulation of Nts and Nts receptor-expressing cells suggest that, even in the brain, not all Nts circuitry exerts the same function. Intriguingly, there may be dedicated brain regions and circuits via which Nts specifically suppresses feeding behavior and weight gain vs other Nts-attributed physiology. Defining the central mechanisms by which Nts signaling modifies body weight may suggest strategies to correct disrupted energy balance, as needed to address overweight, obesity, and eating disorders.
Subject(s)
Body Weight , Brain/metabolism , Neurotensin/metabolism , Obesity/metabolism , Obesity/psychology , Animals , Feeding Behavior , Humans , Neurotensin/genetics , Obesity/genetics , Obesity/physiopathology , Receptors, Neurotensin/genetics , Receptors, Neurotensin/metabolismABSTRACT
Upregulation of the neuropeptide neurotensin (NTS) in a subgroup of lung cancers has been linked to poor prognosis. However, the regulatory pathway centered on NTS in lung cancer remains unclear. Here we identified the NTS-specific enhancer in lung adenocarcinoma cells. The AF4/FMR2 (AFF) family protein AFF1 occupies the NTS enhancer and inhibits NTS transcription. Clustering analysis of lung adenocarcinoma gene expression data demonstrated that NTS expression is highly positively correlated with the expression of the oncogenic factor CPS1. Detailed analyses demonstrated that the IL6 pathway antagonizes NTS in regulating CPS1. Thus, our analyses revealed a novel NTS-centered regulatory axis, consisting of AFF1 as a master transcription suppressor and IL6 as an antagonist in lung adenocarcinoma cells.
Subject(s)
Adenocarcinoma of Lung/genetics , Carbamoyl-Phosphate Synthase (Ammonia)/genetics , DNA-Binding Proteins/genetics , Interleukin-6/genetics , Neurotensin/genetics , Transcriptional Elongation Factors/genetics , A549 Cells , Adenocarcinoma of Lung/pathology , Cell Proliferation/genetics , Enhancer Elements, Genetic/genetics , Female , Gene Expression Regulation, Neoplastic/genetics , Humans , Male , Prognosis , Signal Transduction/geneticsABSTRACT
Numerous peptides including bombesin (BB), endothelin (ET), neurotensin (NTS) and pituitary adenylate cyclase-activating polypeptide (PACAP) are growth factors for lung cancer cells. The peptides bind to G protein-coupled receptors (GPCRs) resulting in elevated cAMP and/or phosphatidylinositol (PI) turnover. In contrast, growth factors such as epidermal growth factor (EGF) or neuregulin (NRG)-1 bind to receptor tyrosine kinases (RTKs) such as the EGFR or HER3, increasing tyrosine kinase activity, resulting in the phosphorylation of protein substrates such as PI3K or phospholipase (PL)C. Peptide GPCRs can transactivate numerous RTKs, especially members of the EGFR/HER family resulting in increased phosphorylation of ERK, leading to cellular proliferation or increased phosphorylation of AKT, leading to cellular survival. GRCR antagonists and tyrosine kinase inhibitors are useful agents to prevent RTK transactivation and inhibit proliferation of cancer cells.
Subject(s)
Bombesin/genetics , Endothelins/genetics , Lung Neoplasms/genetics , Neurotensin/genetics , Epidermal Growth Factor , ErbB Receptors/genetics , Humans , Lung Neoplasms/pathology , Neuregulin-1/genetics , Phosphatidylinositol 3-Kinases/genetics , Pituitary Adenylate Cyclase-Activating Polypeptide/genetics , Receptor, ErbB-3 , Receptors, G-Protein-Coupled/genetics , Type C Phospholipases/geneticsABSTRACT
The present study aimed to determine the primary sequence of ovine xenin and clarify the mRNA expression and peptide localization of xenin in the gastrointestinal tract in sheep. The colocalization of xenin and glucose-dependent insulinotropic polypeptide was also compared in the antrum and duodenum. Analysis of the nucleotide sequence of ovine xenin revealed a high degree (97.9%) of sequence homology of the sequence between sheep and cattle, and the amino acids sequence determined for ovine xenin coincided (100%) with that of other mammalian species. Real-time quantitative PCR for ovine xenin did not show regional difference in the mRNA expression ratio of xenin. In contrast to the real-time quantitative PCR results, anti-xenin positive cells were abundantly localized in the abomasal antrum (P < 0.01) and at a lesser amount in the duodenum, but no antixenin positive cells were observed in the other regions. Anti-xenin single-positive cells were in a majority in the abomasal antrum, whereas anti-xenin single-positive cells, and anti-GIP single-positive cells, and double-positive cells were even colocalized in the duodenum. These results suggest that abomasal antrum is a major source of xenin in the ovine gastrointestinal tract.
Subject(s)
Gastrointestinal Tract/chemistry , Gastrointestinal Tract/metabolism , Gene Expression , Neurotensin/genetics , RNA, Messenger/analysis , Sheep/metabolism , Amino Acid Sequence , Animals , Base Sequence , Gastric Inhibitory Polypeptide/analysis , Immunohistochemistry , Male , Neurotensin/chemistryABSTRACT
Chromatin remodeling impacts the structural neighborhoods and regulates gene expression. However, the role of enhancer-guided chromatin remodeling in the gene regulation remains unclear. Here, using RNA-seq and ChIP-seq, we identified for the first time that neurotensin (NTS) serves as a key oncogene in uveal melanoma and that CTCF interacts with the upstream enhancer of NTS and orchestrates an 800 kb chromosomal loop between the promoter and enhancer. Intriguingly, this novel CTCF-guided chromatin loop was ubiquitous in a cohort of tumor patients. In addition, a disruption in this chromosomal interaction prevented the histone acetyltransferase EP300 from embedding in the promoter of NTS and resulted in NTS silencing. Most importantly, in vitro and in vivo experiments showed that the ability of tumor formation was significantly suppressed via deletion of the enhancer by CRISPR-Cas9. These studies delineate a novel onco-enhancer guided epigenetic mechanism and provide a promising therapeutic concept for disease therapy.
Subject(s)
CCCTC-Binding Factor/genetics , Carcinogenesis/genetics , E1A-Associated p300 Protein/genetics , Melanoma/genetics , Neurotensin/genetics , Uveal Neoplasms/genetics , Animals , CCCTC-Binding Factor/metabolism , CRISPR-Cas Systems , Carcinogenesis/metabolism , Carcinogenesis/pathology , Case-Control Studies , Cell Line, Tumor , Cell Movement , Cell Proliferation , E1A-Associated p300 Protein/metabolism , Enhancer Elements, Genetic , Epigenesis, Genetic , Gene Expression Regulation, Neoplastic , Humans , Male , Melanocytes/metabolism , Melanocytes/pathology , Melanoma/metabolism , Melanoma/mortality , Melanoma/pathology , Mice , Mice, Nude , Neurotensin/antagonists & inhibitors , Neurotensin/metabolism , Promoter Regions, Genetic , Sequence Deletion , Survival Analysis , Tumor Burden , Uveal Neoplasms/metabolism , Uveal Neoplasms/mortality , Uveal Neoplasms/pathology , Xenograft Model Antitumor AssaysABSTRACT
Neurotensin (NTS)-polyplex is a multicomponent nonviral vector that enables gene delivery via internalization of the neurotensin type 1 receptor (NTSR1) to dopaminergic neurons and cancer cells. An approach to improving its therapeutic safety is replacing the viral karyophilic component (peptide KPSV40; MAPTKRKGSCPGAAPNKPK), which performs the nuclear import activity, by a shorter synthetic peptide (KPRa; KMAPKKRK). We explored this issue and the mechanism of plasmid DNA translocation through the expression of the green fluorescent protein or red fluorescent protein fused with KPRa and internalization assays and whole-cell patch-clamp configuration experiments in a single cell together with importin α/ß pathway blockers. We showed that KPRa electrostatically bound to plasmid DNA increased the transgene expression compared with KPSV40 and enabled nuclear translocation of KPRa-fused red fluorescent proteins and plasmid DNA. Such translocation was blocked with ivermectin or mifepristone, suggesting importin α/ß pathway mediation. KPRa also enabled NTS-polyplex-mediated expression of reporter or physiological genes such as human mesencephalic-derived neurotrophic factor (hMANF) in dopaminergic neurons in vivo. KPRa is a synthetic monopartite peptide that showed nuclear import activity in NTS-polyplex vector-mediated gene delivery. KPRa could also improve the transfection of other nonviral vectors used in gene therapy.
Subject(s)
Drug Carriers/chemical synthesis , Gene Transfer Techniques , Genetic Vectors/administration & dosage , Neurotensin/administration & dosage , Peptide Fragments/chemical synthesis , Active Transport, Cell Nucleus , Animals , Cell Line , Cell Nucleus/metabolism , Dopaminergic Neurons/cytology , Dopaminergic Neurons/metabolism , Genetic Therapy/methods , Genetic Vectors/genetics , Male , Mice , Models, Animal , Nanoparticles/chemistry , Neurotensin/genetics , Neurotensin/pharmacokinetics , Patch-Clamp Techniques , Plasmids/genetics , Rats , Receptors, Neurotensin/metabolism , Single-Cell Analysis , Stereotaxic TechniquesABSTRACT
Introduction: Colorectal Cancer (CRC) accounts for 9% of cancer deaths globally. Hormonal pathways play important roles in some cancers. This study investigated the association of CRC expression of neurotensin (NTS), NTS receptors 1 and 3 (NTSR1 and NTSR3) and clinical outcomes. Methods: A prospective cohort study which quantifies the protein expression of NTS, NTSR1 and NTSR3 in human CRCs using immunohistochemistry. Expression levels were then compared with clinico-pathological outcome including histological grade, overall survival (OS) and disease-free survival (DFS). Results: Sixty-four patients were enrolled with median follow-up of 44.0 months. There was significantly higher expression of NTS in cancer tissue in CRC with higher T stages (p < 0.01), N stages (p = 0.03), and AJCC clinical stages (p = 0.04). There was significantly higher expression of NTS, NTSR1 and NTSR3 in cancer tissue compared to surrounding normal epithelium (median H-score 163.5 vs 97.3, p < 0.01). There was significantly shorter DFS in individuals with CRC with high levels of NTS compared to lower levels of NTS (35.8 months 95% CI 28.7-42.8 months vs 46.4 months 95% CI 42.2-50.5 months, respectively, p = 0.02). Above median NTS expression in cancer tissue was a significant risk factor for disease recurrence (HR 4.10, 95% CI 1.14-14.7, p = 0.03). Discussion: The expression of NTS and its receptors has the potential to be utilised as a predictive and prognostic marker in colorectal cancer for postoperative selection for adjuvant therapy and identify individuals for novel therapies targeting the neurotensinergic pathways. Conclusions: High NTS expression appears to be associated with more advanced CRC and worse DFS.
Subject(s)
Adenocarcinoma/metabolism , Biomarkers, Tumor/genetics , Colorectal Neoplasms/metabolism , Neurotensin/genetics , Receptors, Neurotensin/genetics , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Aged , Aged, 80 and over , Biomarkers, Tumor/metabolism , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Female , Humans , Male , Middle Aged , Neurotensin/metabolism , Receptors, Neurotensin/metabolismABSTRACT
BACKGROUND & AIMS: Neurotensin (NTS), a 13-aminoacid peptide localized in central nervous system and gastrointestinal tract, is involved in lipid metabolism and promotes various cancers onset mainly by binding to neurotensin receptor 1 (NTSR1). Increased plasma levels of pro-NTS, the stable NTS precursor, have been associated with type 2 diabetes (T2D), cardiovascular diseases and metabolic associated fatty liver disease (MAFLD). We aimed to evaluate 1) the impact of NTS rs1800832 and NTSR1 rs6090453 genetic variants on liver damage in 1166 MAFLD European individuals, 2) the relation between NTS variant and circulating pro-NTS and 3) the hepatic NTS expression by RNAseq transcriptomic analysis in 125 bariatric patients. RESULTS: The NTS rs1800832 G allele was associated with hepatic fibrosis (OR 1.27, 95% confidence interval (CI). 1.02-1.58; p = 0.03), even more in carriers of both NTS and NTSR1 G risk alleles (OR 1.17, 95% CI. 1.03-1.34; p = 0.01), with cirrhosis (OR 1.58, 95% CI. 1.07-2.34; p = 0.02) and HCC (OR 1.98, 95% CI. 1.24-3.2; p = 0.004). Pro-NTS circulating levels were correlated with T2D (p = 0.005), BMI, (p = 0.04), age (p = 0.0016), lobular inflammation (p = 0.0025), fibrosis>2 (p < 0.0001), cirrhosis (p = 0.0009) and HCC (p < 0.0001) and more so after stratification for the NTS G allele. Transcriptomic data showed that hepatic NTS expression correlated with that of fibrogenic genes (p < 0.05). CONCLUSIONS: NTS rs1800832 variant is associated with advanced fibrosis and HCC in MAFLD patients likely affecting NTS protein activity. The rs6090453 NTSR1 gene variant synergizes with NTS rs1800832 mutation to promote liver damage. Prospective studies are necessary to confirm NTS role in liver disease progression.
Subject(s)
Carcinoma, Hepatocellular/genetics , Fatty Liver/genetics , Liver Neoplasms/genetics , Neurotensin/genetics , Aged , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Proliferation/genetics , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/pathology , Fatty Liver/metabolism , Fatty Liver/pathology , Female , Fibrosis/genetics , Fibrosis/metabolism , Fibrosis/pathology , Gene Expression Regulation/genetics , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Male , Middle Aged , Mutation/genetics , Receptors, Neurotensin/geneticsABSTRACT
This study aimed to explore the detailed molecular mechanism and biomarkers in spinal cord injury (SCI). Gene expression profiles of GSE125630 were downloaded from the Gene Expression Omnibus (GEO) database, and comprised 14 spinal cord tissues, including contusion SCI group (n = 6, unexercised), complete transection group (n = 4, unexercised), and uninjured control group (n = 4, unexercised). Differentially expressed gene (DEG) and time-series gene investigations, functional enrichment analysis, protein-protein interaction (PPI) network construction, characteristic gene-related disease analysis, and TF-target gene interaction studies were performed. A total of 122 DEGs and 409 DEGs were respectively identified in contusion SCI versus control group and complete transection versus control group, respectively. The PPI network investigated 16 characteristic genes including corticotropin-releasing hormone (CRH), tyrosine hydroxylase (TH), and neurotensin (NTS). These genes were mainly enriched in functions involving response to ethanol, corticosterone, and estradiol. Eventually, a TF-target gene interaction network was constructed with nine TFs [including activating transcription factor 3 (ATF3)] and 10 characteristic genes. The results indicate that regulation of osteoblast differentiation and positive regulation of the BMP signaling pathway may be suppressed in the process of SCI. TH may play a pivotal role in the progression of SCI. In addition, DEGs such as CRH and NTS may be novel targets for SCI therapy.