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A zinc metallopeptidase neurolysin (Nln) processes diverse bioactive peptides to regulate signaling in the mammalian nervous system. To understand how Nln interacts with various peptides with dissimilar sequences, we determined crystal structures of Nln in complex with diverse peptides including dynorphins, angiotensin, neurotensin, and bradykinin. The structures show that Nln binds these peptides in a large dumbbell-shaped interior cavity constricted at the active site, making minimal structural changes to accommodate different peptide sequences. The structures also show that Nln readily binds similar peptides with distinct registers, which can determine whether the peptide serves as a substrate or a competitive inhibitor. We analyzed the activities and binding of Nln toward various forms of dynorphin A peptides, which highlights the promiscuous nature of peptide binding and shows how dynorphin A (1-13) potently inhibits the Nln activity while dynorphin A (1-8) is efficiently cleaved. Our work provides insights into the broad substrate specificity of Nln and may aid in the future design of small molecule modulators for Nln.
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Dinorfinas , Neurotensina , Humanos , Especificidad por Sustrato , Dinorfinas/química , Dinorfinas/metabolismo , Neurotensina/química , Neurotensina/metabolismo , Metaloendopeptidasas/metabolismo , Metaloendopeptidasas/química , Metaloendopeptidasas/antagonistas & inhibidores , Unión Proteica , Cristalografía por Rayos X , Modelos Moleculares , Dominio Catalítico , Bradiquinina/química , Bradiquinina/metabolismo , Angiotensinas/metabolismo , Angiotensinas/química , Secuencia de AminoácidosRESUMEN
Elevated levels of the gut pro-hormone Proneurotensin (proNT) have been found to predict development of cardiovascular disease. However, it is still unknown whether higher proNT levels are associated with subclinical vascular damage. Herein, we investigated the relationship between higher proNT concentrations and augmented pulse pressure (PP) and carotid intima-media thickness (cIMT), indicators of increased arterial stiffness and subclinical atherosclerosis, respectively. Clinical characteristics, PP and cIMT were evaluated in 154 non-diabetic individuals stratified into tertiles according to fasting serum proNT concentrations. We found that, subjects with higher proNT levels exhibited a worse lipid profile and insulin sensitivity, increased C-reactive protein levels, along with higher values of PP and cIMT as compared to the lowest proNT tertile. Prevalence of elevated PP (≥ 60 mmHg) and subclinical carotid atherosclerosis (IMT > 0.9 mm) was increased in the highest tertile of proNT. In a logistic regression analysis adjusted for several confounders, subjects with higher proNT levels displayed a fivefold raised risk of having elevated PP values (OR 5.36; 95%CI 1.04-27.28; P = 0.05) and early carotid atherosclerosis (OR 4.81; 95%CI 1.39-16.57; P = 0.01) as compared to the lowest proNT tertile. In conclusion, higher circulating levels of proNT are a biomarker of subclinical vascular damage independent of other atherosclerotic risk factors.
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Presión Sanguínea , Grosor Intima-Media Carotídeo , Precursores de Proteínas , Humanos , Masculino , Femenino , Persona de Mediana Edad , Precursores de Proteínas/sangre , Adulto , Neurotensina/sangre , Enfermedades de las Arterias Carótidas/sangre , Rigidez Vascular , Factores de Riesgo , Proteína C-Reactiva/metabolismo , Proteína C-Reactiva/análisis , Biomarcadores/sangre , Aterosclerosis/sangre , AncianoRESUMEN
Animals must simultaneously select and balance multiple action contingencies in ambiguous situations: for instance, evading danger during feeding. This has rarely been examined in the context of information selection; despite corticothalamic pathways that mediate sensory attention being relatively well characterized, neural mechanisms filtering conflicting actions remain unclear. Here, we develop a new loom/feed test to observe conflict between naturally induced fear and feeding and identify a novel anterior cingulate cortex (ACC) output to the ventral anterior and ventral lateral thalamus (VA/VL) that adjusts selectivity between these innate actions. Using micro-endoscopy and fiber photometry, we reveal that activity in corticofugal outputs was lowered during unbalanced/singularly occupied periods, as were the resulting decreased thalamic initiation-related signals for less-favored actions, suggesting that the integration of ACC-thalamic firing may directly regulate the output of behavior choices. Accordingly, the optoinhibition of ACC-VA/VL circuits induced high bias toward feeding at the expense of defense. To identify upstream "commander" cortical cells gating this output, we established dual-order tracing (DOT)-translating ribosome affinity purification (TRAP)-a scheme to label upstream neurons with transcriptome analysis-and found a novel population of neurotensin-positive interneurons (ACCNts). The photoexcitation of ACCNts cells indeed caused similarly hyper-selective behaviors. Collectively, this new "corticofugal action filter" scheme suggests that communication in multi-step cingulate circuits may critically influence the summation of motor signals in thalamic outputs, regulating bias between innate action types.
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Giro del Cíngulo , Vías Nerviosas , Neurotensina , Animales , Giro del Cíngulo/metabolismo , Giro del Cíngulo/fisiología , Ratones , Masculino , Vías Nerviosas/fisiología , Neurotensina/metabolismo , Tálamo/metabolismo , Tálamo/fisiología , Ratones Endogámicos C57BL , Miedo/fisiología , Conducta AlimentariaRESUMEN
The development of multitarget opioid drugs has emerged as an attractive approach for innovative pain management with reduced side effects. In the present study, a novel hybrid peptide BNT12 containing the opioid and neurotensin (NT)-like fragments was synthesized and pharmacologically characterized. In acute radiant heat paw withdrawal test, intracerebroventricular (i.c.v.) administration of BNT12 produced potent antinociception in mice. The central antinociceptive activity of BNT12 was mainly mediated by µ-, δ-opioid receptor, neurotensin receptor type 1 (NTSR1) and 2 (NTSR2), supporting a multifunctional agonism of BNT12 in the functional assays. BNT12 also exhibited significant antinociceptive effects in spared nerve injury (SNI)-neuropathic pain, complete Freund's adjuvant (CFA)-induced inflammatory pain, acetic acid-induced visceral and formalin-induced pain after i.c.v. administration. Furthermore, BNT12 exhibited substantial reduction of acute antinociceptive tolerance, shifted the dose-response curve to the right by only 1.3-fold. It is noteworthy that BNT12 showed insignificant chronic antinociceptive tolerance at the supraspinal level. In addition, BNT12 exhibited reduced or no opioid-like side effects on conditioned place preference (CPP) response, naloxone-precipitated withdrawal response, acute hyperlocomotion, motor coordination, gastrointestinal transit, and cardiovascular responses. The present investigation demonstrated that the novel hybrid peptide BNT12 might serve as a promising analgesic candidate with limited opioid-like side effects.
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Neurotensina , Receptores de Neurotensina , Animales , Masculino , Ratones , Neurotensina/análogos & derivados , Neurotensina/farmacología , Neurotensina/química , Receptores de Neurotensina/metabolismo , Receptores de Neurotensina/agonistas , Analgésicos/farmacología , Analgésicos/química , Analgésicos/administración & dosificación , Analgésicos Opioides/farmacología , Analgésicos Opioides/administración & dosificación , Tolerancia a Medicamentos , Dolor/tratamiento farmacológicoRESUMEN
Chronic pain and obesity frequently occur together. An ideal therapy would alleviate pain without weight gain, and most optimally, could promote weight loss. The neuropeptide neurotensin (Nts) has been separately implicated in reducing weight and pain but could it be a common actionable target for both pain and obesity? Here we review the current knowledge of Nts signaling via its receptors in modulating body weight and pain processing. Evaluating the mechanism by which Nts impacts ingestive behavior, body weight, and analgesia has potential to identify common physiologic mechanisms underlying weight and pain comorbidities, and whether Nts may be common actionable targets for both.
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Dolor Crónico , Neurotensina , Obesidad , Humanos , Dolor Crónico/tratamiento farmacológico , Comorbilidad , Animales , Peso Corporal , Conducta Alimentaria , Receptores de NeurotensinaRESUMEN
Neurotensin (NTS) is a 13-amino acid peptide which is highly expressed in the mammalian ovary in response to the luteinizing hormone surge. Antibody neutralization of NTS in the ovulatory follicle of the cynomolgus macaque impairs ovulation and induces follicular vascular dysregulation, with excessive pooling of red blood cells in the follicle antrum. We hypothesize that NTS is an essential intrafollicular regulator of vascular permeability. In the present study, follicle injection of the NTS receptor antagonist SR142948 also resulted in vascular dysregulation. To measure vascular permeability changes in vitro, primary macaque ovarian microvascular endothelial cells (mOMECs) were enriched from follicle aspirates and studied in vitro. When treated with NTS, permeability of mOMECs decreased. RNA sequencing (RNA-Seq) of mOMECs revealed high mRNA expression of the permeability-regulating adherens junction proteins N-cadherin (CDH2) and K-cadherin (CDH6). Immunofluorescent detection of CDH2 and CDH6 confirmed expression and localized these cadherins to the cell-cell boundaries, consistent with function as components of adherens junctions. mOMECs did not express detectable levels of the typical vascular endothelial cadherin, VE-cadherin (CDH5) as determined by RNA-Seq, qPCR, western blot, and immunofluorescence. Knockdown of CDH2 or CDH6 via siRNA abrogated the NTS effect on mOMEC permeability. Collectively, these data suggest that NTS plays an ovulation-critical role in vascular permeability maintenance, and that CDH2 and CDH6 are involved in the permeability modulating effect of NTS on the ovarian microvasculature. NTS can be added to a growing number of angiogenic regulators which are critical for successful ovulation.
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Células Endoteliales , Ovario , Femenino , Animales , Ovario/metabolismo , Células Endoteliales/metabolismo , Neurotensina/metabolismo , Uniones Adherentes/metabolismo , Permeabilidad Capilar , Cadherinas/genética , Cadherinas/metabolismo , Macaca/metabolismo , Permeabilidad , Endotelio Vascular/metabolismo , Mamíferos/metabolismoRESUMEN
On the verge of a theranostic approach to personalised medicine, copper-64 is one of the emerging radioisotopes in nuclear medicine due to its exploitable nuclear and biochemical characteristics. The increased demand for copper-64 for preclinical and clinical studies has prompted the development of production routes. This research aims to compare the (p,n) reaction on nickel-64 solid versus liquid targets and evaluate the effectiveness of [64Cu]CuCl2 solutions prepared by the two routes. As new treatments for neurotensin receptor-overexpressing tumours have developed, copper-64 was used to radiolabel Neurotensin (8-13) and Neuromedin N. High-quality [64Cu]CuCl2 solutions were prepared using ACSI TR-19 and IBA Cyclone Kiube cyclotrons. The radiochemical purity after post-irradiation processing reached 99% (LT) and 99.99% (ST), respectively. The irradiation of a solid target with 11.8 MeV protons and 150 µAh led to 704 ± 84 MBq/µA (17.6 ± 2.1 GBq/batch at EOB). At the end of the purification process (1 h, 90.90% activity yield), the solution for peptide radiolabelling had a radioactive concentration of 1340.4 ± 70.1 MBq/mL (n.d.c.). The irradiation of a liquid target with 16.9 MeV protons and 230 µAh resulted in 3.7 ± 0.2 GBq/batch at EOB, which corresponds to an experimental production yield of 6.89 GBq.cm3/(g.µA)sat. Benefiting from a shorter purification process (40 min), the activity yielded 90.87%, while the radioactive concentration of the radiolabelling solution was lower (492 MBq/mL, n.d.c.). The [64Cu]CuCl2 solutions were successfully used for the radiolabelling of DOTA-NT(8-13) and DOTA-NN neuropeptides, resulting in a high RCP (>99%) and high molar activity (27.2 and 26.4 GBq/µmol for LT route compared to 45 and 52 GBq/µmol for ST route, respectively). The strong interaction between the [64Cu]Cu-DOTA-NT(8-13) and the colon cancerous cell lines HT29 and HCT116 proved that the specificity for NTR had not been altered, as shown by the uptake and retention data.
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Radioisótopos de Cobre , Fragmentos de Péptidos , Protones , Cobre , Neurotensina , Radioisótopos , RadiofármacosRESUMEN
The diagnosis and treatment of biliary atresia pose challenges due to the absence of reliable biomarkers and limited understanding of its etiology. The plasma and liver of patients with biliary atresia exhibit elevated levels of neurotensin. To investigate the specific role of neurotensin in the progression of biliary atresia, the patient's liver pathological section was employed. Biliary organoids, cultured biliary cells, and a mouse model were employed to elucidate both the potential diagnostic significance of neurotensin and its underlying mechanistic pathway. In patients' blood, the levels of neurotensin were positively correlated with matrix metalloprotease-7, interleukin-8, and liver function enzymes. Neurotensin and neurotensin receptors were mainly expressed in the intrahepatic biliary cells and were stimulated by bile acids. Neurotensin suppressed the growth and increased expression of matrix metalloprotease-7 in biliary organoids. Neurotensin inhibited mitochondrial respiration, oxidative phosphorylation, and attenuated the activation of calmodulin-dependent kinase kinase 2-adenosine monophosphate-activated protein kinase (CaMKK2-AMPK) signaling in cultured biliary cells. The stimulation of neurotensin in mice and cultured cholangiocytes resulted in the upregulation of matrix metalloprotease-7 expression through binding to its receptors, namely neurotensin receptors 1/3, thereby attenuating the activation of the CaMKK2-AMPK pathway. In conclusion, these findings revealed the changes of neurotensin in patients with cholestatic liver disease and its mechanism in the progression of the disease, providing a new understanding of the complex mechanism of hepatobiliary injury in children with biliary atresia.
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Atresia Biliar , Hepatopatías , Animales , Niño , Humanos , Ratones , Proteínas Quinasas Activadas por AMP/metabolismo , Atresia Biliar/metabolismo , Atresia Biliar/patología , Hígado/metabolismo , Hepatopatías/metabolismo , Metaloproteasas/metabolismo , Neurotensina/metabolismo , Receptores de Neurotensina/metabolismoRESUMEN
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.
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Aterosclerosis , Neurotensina , Placa Aterosclerótica , Triglicéridos , Animales , Femenino , Humanos , Masculino , Ratones , Aterosclerosis/sangre , Modelos Animales de Enfermedad , Ácidos Grasos/metabolismo , Ácidos Grasos/sangre , Ratones Endogámicos C57BL , Ratones Noqueados , Neurotensina/sangre , Neurotensina/genética , Neurotensina/metabolismo , Precursores de Proteínas , Receptores de LDL/genética , Receptores de LDL/deficiencia , Factores de Riesgo , Triglicéridos/sangre , Triglicéridos/metabolismoRESUMEN
The central nucleus of the amygdala is known to play key roles in alcohol use and affect. Neurotensin neurons in the central nucleus of the amygdala have been shown to regulate alcohol drinking in male mice. However, little is known about which neurotransmitters released by these cells drive alcohol consumption or whether these cells drive alcohol consumption in female mice. Here we show that knockdown of GABA release from central amygdala neurotensin neurons using a Nts-cre-dependent vGAT-shRNA-based AAV strategy reduces alcohol drinking in male, but not female, mice. This manipulation did not impact avoidance behavior, except in a fasted novelty-suppressed feeding test, in which vGAT shRNA mice demonstrated increased latency to feed on a familiar high-value food reward, an effect driven by male mice. In contrast, vGAT shRNA female mice showed heightened sensitivity to thermal stimulation. These data show a role for GABA release from central amygdala neurotensin neurons in modulating consumption of rewarding substances in different motivational states.
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Consumo de Bebidas Alcohólicas , Núcleo Amigdalino Central , Neuronas , Neurotensina , Ácido gamma-Aminobutírico , Animales , Femenino , Masculino , Núcleo Amigdalino Central/metabolismo , Núcleo Amigdalino Central/efectos de los fármacos , Neurotensina/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Consumo de Bebidas Alcohólicas/metabolismo , Consumo de Bebidas Alcohólicas/genética , Ratones , Ratones Endogámicos C57BL , Caracteres Sexuales , Etanol/administración & dosificación , Etanol/farmacología , Proteínas del Transporte Vesicular de Aminoácidos InhibidoresRESUMEN
Schizophrenia (SZ) is a serious mental illness and neuropsychiatric brain disorder with behavioral symptoms that include hallucinations, delusions, disorganized behavior, and cognitive impairment. Regulation of such behaviors requires utilization of neurotransmitters released to mediate cell-cell communication which are essential to brain functions in health and disease. We hypothesized that SZ may involve dysregulation of neurotransmitters secreted from neurons. To gain an understanding of human SZ, induced neurons (iNs) were derived from SZ patients and healthy control subjects to investigate peptide neurotransmitters, known as neuropeptides, which represent the major class of transmitters. The iNs were subjected to depolarization by high KCl in the culture medium and the secreted neuropeptides were identified and quantitated by nano-LC-MS/MS tandem mass spectrometry. Several neuropeptides were identified from schizophrenia patient-derived neurons, including chromogranin B (CHGB), neurotensin, and natriuretic peptide. Focusing on the main secreted CHGB neuropeptides, results revealed differences in SZ iNs compared to control iN neurons. Lower numbers of distinct CHGB peptides were found in the SZ secretion media compared to controls. Mapping of the peptides to the CHGB precursor revealed peptides unique to either SZ or control, and peptides common to both conditions. Also, the iNs secreted neuropeptides under both KCl and basal (no KCl) conditions. These findings are consistent with reports that chromogranin B levels are reduced in the cerebrospinal fluid and specific brain regions of SZ patients. These findings suggest that iNs derived from SZ patients can model the decreased CHGB neuropeptides observed in human SZ.
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Cromogranina B , Neuronas , Neuropéptidos , Neurotransmisores , Esquizofrenia , Humanos , Esquizofrenia/metabolismo , Neuropéptidos/metabolismo , Neuronas/metabolismo , Cromogranina B/metabolismo , Masculino , Neurotransmisores/metabolismo , Femenino , Espectrometría de Masas en Tándem/métodos , Adulto , Persona de Mediana Edad , Neurotensina/metabolismo , Células Cultivadas , Encéfalo/metabolismoRESUMEN
RESEARCH QUESTION: Can the addition of progesterone and neurotensin, molecular agents found in the female reproductive tract, after sperm washing increase the fertilization potential of human spermatozoa? DESIGN: (i) Cohort study of 24 men. Spermatozoa selected by swim-up were incubated in either progesterone or neurotensin (0.1-100 µM) for 1-4 h, and hyperactive motility and binding to hyaluronan (0.1-100 µM) were assessed. The effect of progesterone 10 µM on sperm function was assessed in a blinded manner, including: hyperactive motility, binding to hyaluronan, tyrosine phosphorylation, acrosome reaction and oxidative DNA damage. (i) Embryo safety testing [one-cell mouse embryo assay (MEA), endotoxin and sterility counts (nâ¯=â¯3)] in preclinical embryo models of IVF (murine and porcine, nâ¯=â¯7 each model) and a small preliminary human study (nâ¯=â¯4) of couples undergoing standard IVF with oocytes inseminated with spermatozoa ± 10 µM progesterone. RESULTS: Progesterone 10 µM increased sperm binding to hyaluronan, hyperactive motility and tyrosine phosphorylation (all P < 0.05). Neurotensin had no effect (P > 0.05). Progesterone 10 µM in human embryo culture media passed embryo safety testing (MEA, endotoxin concentration and sterility plate count). In preclinical models of IVF, the exposure of spermatozoa to progesterone 10 µM and oocytes to progesterone 1 µM was not detrimental, and increased the fertilization rate in mice and the blastocyst cell number in mice and pigs (all P ≤ 0.03). In humans, every transferred blastocyst that had been produced from spermatozoa exposed to progesterone resulted in a live birth. CONCLUSION: The addition of progesterone to sperm preparation media shows promise as an adjunct to current methods for increasing fertilization potential. Randomized controlled trials are required to determine the clinical utility of progesterone for improving IVF outcomes.
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Infertilidad , Progesterona , Humanos , Masculino , Femenino , Animales , Ratones , Porcinos , Progesterona/farmacología , Progesterona/metabolismo , Fertilización In Vitro/métodos , Neurotensina/metabolismo , Neurotensina/farmacología , Ácido Hialurónico/farmacología , Estudios de Cohortes , Semen , Espermatozoides/metabolismo , Infertilidad/metabolismo , Tirosina/metabolismo , Endotoxinas/metabolismo , Endotoxinas/farmacologíaRESUMEN
OBJECTIVE: The aim of this systematic review was to update the current level of evidence for spinal manipulation in influencing various biochemical markers in healthy and/or symptomatic population. METHODS: This is a systematic review update. Various databases were searched (inception till May 2023) and fifteen trials (737 participants) that met the inclusion criteria were included in the review. Two authors independently screened, extracted and assessed the risk of bias in included studies. Outcome measure data were synthesized using standard mean differences and meta-analysis for the primary outcome (biochemical markers). The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) was used for assessing the quality of the body of evidence for each outcome of interest. RESULTS: There was low-quality evidence that spinal manipulation influenced various biochemical markers (not pooled). There was low-quality evidence of significant difference that spinal manipulation is better (SMD -0.42, 95% CI - 0.74 to -0.1) than control in eliciting changes in cortisol levels immediately after intervention. Low-quality evidence further indicated (not pooled) that spinal manipulation can influence inflammatory markers such as interleukins levels post-intervention. There was also very low-quality evidence that spinal manipulation does not influence substance-P, neurotensin, oxytocin, orexin-A, testosterone and epinephrine/nor-epinephrine. CONCLUSION: Spinal manipulation may influence inflammatory and cortisol post-intervention. However, the wider prediction intervals in most outcome measures point to the need for future research to clarify and establish the clinical relevance of these changes.
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Manipulación Espinal , Humanos , Hidrocortisona , Neurotensina , Biomarcadores , EpinefrinaRESUMEN
Inflammation-mediated reproductive health problems in females have become an emerging concern. The present investigation was aimed to elucidate the efficacy of the PD149163, agonist of the type I neurotensin receptor, in preventing/ameliorating the lipopolysaccharide (LPS) induced inflammation of the female reproductive system of the mice. Female Swiss Albino Mice (8 weeks old) were maintained in three groups (6/group): Group I as Control, Group II and Group III were exposed to intraperitoneal (i.p) LPS (1 mg/kg bw) for 5 days followed by treatment with PD149163 (100 µg/kg BW i.p.) to Group III (LPS + PD) for 28 days. After termination of the experiment on 29th day, plasma levels of inflammatory cytokines, LH, FSH, estradiol, corticosterone, oxidative stress effects in the ovary and histopathological study of the ovary and uterine horn were done. LPS-induced inflammation of the ovary and uterine horn was ameliorated/prevented by PD149163 as reflected in the reduced histopathological scores, significant elevation of the plasma anti-inflammatory cytokine IL-10 and decrease of the pro inflammatory cytokines TNF-α and IL-6. Significant decrease of lipid peroxide, increase of antioxidant defense enzymes, Superoxide dismutase and Catalase in the ovary indicated reduction of oxidative stress. The plasma levels of the reproduction related hormones and corticosterone were restored. PD149163 acts as an anti-inflammatory and anti-oxidative agent in modulation of inflammation in the female reproductive system (ovary & uterine horn). These findings suggest that the therapeutic potential of the analogs of neurotensin including PD149163 should be explored for the treatment of the female reproductive health issues.
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Lipopolisacáridos , Neurotensina , Oligopéptidos , Animales , Femenino , Ratones , Antiinflamatorios/farmacología , Corticosterona , Citocinas , Genitales Femeninos , Inflamación/inducido químicamente , Estrés OxidativoRESUMEN
Neurotensin (NTS) and its receptors (NTSRs) have long been the subject of study and have shown to have a vital function in a variety of systems. They are specifically implicated in the development of tumors and have both oncogenic and anti-apoptotic effects. Neurotensin receptor 2 (NTSR2), like NTSR1, belongs to the G protein-coupled receptor family and has been linked to analgesia, mental disorders, and hematological cancers. However, several research reports have revealed that it exists in numerous different systems. As a result, it seems to be an extremely promising therapeutic target for a variety of diseases. As NTSR2 is particularly prevalent in the brain and has different distribution and developmental characteristics from NTSR1, it may play a specific role in the nervous system. The present review summarizes the expression and function of NTSR2 in different systems, to highlight its potential as a diagnostic tool or therapeutic target.
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Neoplasias , Neurotensina , Humanos , Neurotensina/metabolismo , DolorRESUMEN
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.
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Cabello , Neurotensina , Animales , Humanos , Ratones , Alopecia/metabolismo , Folículo Piloso/metabolismo , Neuropéptidos/metabolismo , Neurotensina/genética , Neurotensina/metabolismo , Neurotensina/farmacología , Receptores de Neurotensina/genética , Receptores de Neurotensina/metabolismo , Cabello/crecimiento & desarrollo , Cabello/metabolismoRESUMEN
Neurotensin (NT) is a 13-amino acid neuropeptide widely distributed in the CNS that has been involved in the pathophysiology of many neural and psychiatric disorders. There are three known neurotensin receptors (NTSRs), which mediate multiple actions, and form the neurotensinergic system in conjunction with NT. NTSR1 is the main mediator of NT, displaying effects in both the CNS and the periphery, while NTSR2 is mainly expressed in the brain and NTSR3 has a broader expression pattern. In this review, we bring together up-to-date studies showing an involvement of the neurotensinergic system in different aspects of the stress response and the main stress-related disorders, such as depression and anxiety, post-traumatic stress disorder (PTSD) and its associated symptoms, such as fear memory and maternal separation, ethanol addiction, and substance abuse. Emphasis is put on gene, mRNA, and protein alterations of NT and NTSRs, as well as behavioral and pharmacological studies, leading to evidence-based suggestions on the implicated regulating mechanisms as well as their therapeutic exploitation. Stress responses and anxiety involve mainly NTSR1, but also NTSR2 and NTSR3. NTSR1 and NTSR3 are primarily implicated in depression, while NTSR2 and secondarily NTSR1 in PTSD. NTSR1 is interrelated with substance and drug abuse and NTSR2 with fear memory, while all NTSRs seem to be implicated in ethanol consumption. Some of the actions of NT and NTSRs in these pathological settings may be driven through interactions between NT and corticotrophin releasing factor (CRF) in their regulatory contribution, as well as by NT's pro-inflammatory mediating actions.
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Neurotensina , Receptores de Neurotensina , Humanos , Neurotensina/metabolismo , Receptores de Neurotensina/genética , Receptores de Neurotensina/metabolismo , Privación Materna , Encéfalo/metabolismo , EtanolRESUMEN
The conformational ensembles of G protein-coupled receptors (GPCRs) include inactive and active states. Spectroscopy techniques, including NMR, show that agonists, antagonists and other ligands shift the ensemble toward specific states depending on the pharmacological efficacy of the ligand. How receptors recognize ligands and the kinetic mechanism underlying this population shift is poorly understood. Here, we investigate the kinetic mechanism of neurotensin recognition by neurotensin receptor 1 (NTS1) using 19F-NMR, hydrogen-deuterium exchange mass spectrometry and stopped-flow fluorescence spectroscopy. Our results indicate slow-exchanging conformational heterogeneity on the extracellular surface of ligand-bound NTS1. Numerical analysis of the kinetic data of neurotensin binding to NTS1 shows that ligand recognition follows an induced-fit mechanism, in which conformational changes occur after neurotensin binding. This approach is applicable to other GPCRs to provide insight into the kinetic regulation of ligand recognition by GPCRs.
Asunto(s)
Neurotensina , Receptores de Neurotensina , Neurotensina/metabolismo , Receptores de Neurotensina/metabolismo , Ligandos , Receptores Acoplados a Proteínas G/metabolismo , Unión ProteicaRESUMEN
Radiolabeled neurotensin analogs have been developed as candidates for theranostic use against neurotensin subtype 1 receptor (NTS1R)-expressing cancer. However, their fast degradation by two major peptidases, neprilysin (NEP) and angiotensin-converting enzyme (ACE), has hitherto limited clinical success. We have recently shown that palmitoylation at the ε-amine of Lys7 in [99mTc]Tc-[Lys7]DT1 (DT1, N4-Gly-Arg-Arg-Pro-Tyr-Ile-Leu-OH, N4 = 6-(carboxy)-1,4,8,11-tetraazaundecane) led to the fully stabilized [99mTc]Tc-DT9 analog, displaying high uptake in human pancreatic cancer AsPC-1 xenografts but unfavorable pharmacokinetics in mice. Aiming to improve the in vivo stability of [99mTc]Tc-DT1 without compromising pharmacokinetics, we now introduce three new [99mTc]Tc-DT1 mimics, carrying different pendant groups at the ε-amine of Lys7: MPBA (4-(4-methylphenyl)butyric acid)-[99mTc]Tc-DT10; MPBA via a PEG4-linker-[99mTc]Tc-DT11; or a hydrophilic PEG6 chain-[99mTc]Tc-DT12. The impact of these modifications on receptor affinity and internalization was studied in NTS1R-positive cells. The effects on stability and AsPC-1 tumor uptake were assessed in mice without or during NEP/ACE inhibition. Unlike [99mTc]Tc-DT10, the longer-chain modified [99mTc]Tc-DT11 and [99mTc]Tc-DT12 were significantly stabilized in vivo, resulting in markedly improved tumor uptake compared to [99mTc]Tc-DT1. [99mTc]Tc-DT11 was found to achieve the highest AsPC-1 tumor values and good pharmacokinetics, either without or during NEP inhibition, qualifying for further validation in patients with NTS1R-positive tumors using SPECT/CT.