European Journal of Neurodegenerative Diseases 2024; 13(2) May-August: 42-47
NEUROTENSIN AFFECTS METABOLISM, INFLAMMATION, AND NEUROLOGICAL PATHOLOGIES INVOLVING MAST CELLS
R. Pellegrino *
Physiatrist and Pain Therapist, Lecce-Castromediano/Cavallino, Via S. Pelico, Lecce, Italy.
*Correspondence to:
Dr. R. Pellegrino,
Physiatrist and Pain Therapist,
Lecce-Castromediano/Cavallino,
Via S. Pelico 34,
73100 Lecce, Italy.
e-mail: drpellegrino@yahoo.it
ABSTRACT
Neurotensin (NTS) is a neurotransmitter and neuromodulator with 13 amino acids that has paracranial and endocrine effects on various organs. NTS can have a stimulating effect on both normal and cancer cells. Additionally, it stimulates the anterior pituitary gland to produce hormones that reduce pain. At the brain level, NTS is closely associated with the effects of dopamine and is therefore involved in neurological disorders. NTS is derived from the pro-NTS precursor and is transcribed via mRNA involving the c-Fos and AP-1 genes. NTS acts through three receptors: NTSR-1, 2, and 3; NTSR-1 and NTSR-2 belong to a class of G-coupled proteins and have several similarities, while NTSR-3 seems to be slightly different from the other two and has yet to be defined. NTS is a modulator of the digestive tract and cardiovascular system, and participates in fat absorption and regulation of energy homeostasis. In rodent experiments, NTS mediates inflammation and metabolic diseases associated with obesity, and its level is high in hepatic steatosis. In addition, NTS activates MCs to produce inflammatory mediators that can affect the central nervous system (CNS). However, more studies are needed to clarify the exact function of NTS and whether this protein could be a therapeutic target.
KEYWORDS: neurotensin, neurotensin receptor, metabolism, inflammation, neurological pathology, mast cell
INTRODUCTION
Neurotensin (NTS) is a peptide of 13 amino acids that functions as a brain neurotransmitter and neuromodulator and was isolated by Carraway and Leeman in 1973 (1). In the brain, NTS modulates dopaminergic transmission, while at the peripheral level, it is a paracrine and endocrine modulator of the cardiovascular and digestive systems (2). It has been noted that NTS can also have a stimulating action on the growth of normal and tumor cells (3) (Fig.1).
Fig. 1. Neurotensin (NTS) activates neurons and modulates cerebral activity, causing dopaminergic transmission. NTS also influences normal and tumor cells and can cause angiogenesis and IL-8/CXCL1 activation, modulates the cardiovascular system, the digestive system, and the absorption of fat, and by binding to its receptor, activates mast cells (MCs) to release corticotropin-releasing hormone (CRH).
DISCUSSION
NTS is a neuromodulator, with powerful effects on hypothermia stimulation, on the secretion of hormones by the anterior pituitary gland, and on the physiological mechanisms within the body that are capable of blocking or attenuating pain (4). In the central nervous system (CNS), neurotensin is a neuromodulator, particularly concerning dopaminergic transmission, and to a lesser extent, serotonergic and noradrenergic transmission (5). Preventive in vivo treatment with anti-opioid drugs does not abolish the pain-relieving effect induced by NTS, demonstrating that the two pathways of antinociceptive inhibition are different (6).
The function of NTS in the brain is in close association with the action and biological effects of dopamine, whose pathological variations are found in many neurological disorders, such as Parkinson’s disease (7). The biological effects of NTS include psychostimulant and anti-psychotic effects (8).
NTS derives from a larger pro-NTS/neuromedin precursor molecule (pro-NTS/NN), a complex processed and cleaved by endopeptidases that belong to protein convertases (9). The precursor process is tissue-specific and therefore, may be different in various organs (10). For example, the pro-NTS/NN precursor in the brain is processed to form NTS and NN, while in the intestine, there is NTS and a large-NN (11). The inactivation of NN occurs promptly by aminopeptidase, while NTS is inactivated by metalloendopeptidases (12). It appears that NN is a neuropeptide that is mostly localized in the brain, while large NN is produced in the intestine and functions as a hormone that is transported by the peripheral blood (13). At the genetic level, NTS appears to be transcribed through precursor mRNA involving c-Fos and AP-1 (14).
The NTS receptors (NTSR) are NTSR-1, NTSR-2, and NTSR-3 (15). NTSR-1 and NTSR-2 belong to a class of G-coupled proteins and have several similarities, while NTSR-3 seems to be slightly different from the other two and has yet to be defined (15). The best-known and first-synthesized NTS receptors are NTSR-1 and NTSR-2 (16).
NTS binds to NTSR-1 with high affinity, while the NTSR-2 receptor has low activity for this neurotransmitter. These receptors are distributed differently in the CNS; for example, NTSR-1 seems to be expressed predominantly in neurons, while NTSR-2 is expressed more greatly in glia (17). In humans, NTSR-1 is composed of 418 amino acids located on chromosome 20q13 and its activation with NTS involves the increase in calcium ions (Ca2+), IP3, and the activation of phospholipase C (PLC) at the intracellular level (18). Receptor internalization appears to be temperature-dependent and is translated in neurons (19). The human NTSR-2 has 401 amino acids and appears to be an antagonist of NTSR-1 (20). The activation of NTSR-2 stimulates mitogen-activated protein kinases (MAPKs), increases the concentration of intracellular Ca2+, and activates IP3 and cAMP, although these processes still need to be confirmed (21).
The mRNA encoding NTSR-2 resides in brain tissue and especially in the cortex, hippocampus, and hypothalamus, and appears to be exclusive to neurons. The NTSR-2 receptor seems to be more involved in analgesia, while NTSR-1 seems to be responsible for the central effects of NTS (22).
Effects of Neurotensin (NTS) on metabolism and inflammation
Among the biological effects of NTS, its participation in the absorption of fats and in the regulation of energy homeostasis should be highlighted (23). NTS is a modulator of the digestive tract and cardiovascular system of mammals and also acts as a growth factor for normal and tumor cells (24). Pro-NTS is associated with obesity and type 2 diabetes mellitus (25). In animal models, NTS has been observed to mediate inflammation of abdominal fat and is a potential cause of type 2 diabetes mellitus, obesity-associated metabolic diseases, and hepatic steatosis (26) NTS is considered a biomarker for hepatic steatosis and obesity and represents a potential therapeutic target (27).
Neuropeptides such as NTS interact with different cell types residing in the gut and play a key role in several aspects of intestinal pathophysiology. NTS is involved in many gastrointestinal pathologies with effects on the neurological, immune, and inflammatory systems (28). NTS directly activates neurons, epithelial, and immune cells with complex and still unclear mechanisms. NTS appears to play a protective role in immunity at the intestinal level, but on the other hand, it appears to activate the acute inflammatory and pathological response (29). Therefore, NTS can be both a pro-inflammatory and anti-inflammatory peptide. At a pro-inflammatory level, NTS participates in the brain-gut axis by activating visceral hypersensitivity, overgrowth of intestinal flora, intestinal inflammation, and hyperreactivity of mast cells (MCs) (30).
MCs are immune cells that mediate both primary and adaptive responses. They are located in tissues, where their maturation occurs through the stimulation by various cytokines such as IL-3, IL-6, and stem cell factor (SCF) (31). MCs are activated by various neuropeptides including substance P (SP), nerve growth factor (NGF) and NTS. When activated by NTS, MCs modulate and secrete numerous molecules such us heparin, nitric oxide (NO), transforming growth factor beta (TGF-b), tumor necrosis factor (TNF), and IL-10, which can have autocrine actions that can be either activating or inhibiting (32).
NTS increases the expression of the corticotropin releasing hormone 1 receptor (CRHR-1) on MCs. In addition, NTS stimulates the secretion of corticotropin releasing hormone (CRH) and VEGF from MCs activated by IgE or anti-IgE (33). NTS has been observed to be increased in the skin of rodents after acute stress, which stimulates MCs and increases vascular permeability (34). In addition, NTS stimulates MCs to produce increased levels of histamine through activation of NTSR (35). MCs located in the skin reside near the ends of sensory nerves and can be activated by neuropeptides including NTS produced by skin cells (36). Protease-producing MCs are capable of degrading NTS, highlighting the crosstalk between NTS and MCs. When activated by NTS, MCs residing in the skin can release chemical mediators of inflammation, making NTS a candidate for therapeutic targets of neuroinflammatory disorders (36).
Microglial cells express NTSR-3 which is involved in their cell proliferation (37) and also in neuroinflammation, after NTS binds to this receptor (38). In synergy with the neuropeptide CRH, NTS increases vascular permeability and causes the breakdown of the blood-brain barrier (BBB), exacerbating inflammatory reactions (39).
Neurotensin (NT) and neurological pathologies
NTS appears to mediate several neurological disorders including autism spectrum disorder (ASD), where this neuropeptide is elevated in the serum of children. In addition, it has been reported that NTS induces the expression of corticotropin-releasing factor-1 (CRF-1), increasing allergic disease mediated by human MCs (40). In an interesting study, NTS was reported to be elevated in the serum of young children with autistic disorder, compared to typically developing controls (41).
NTS could carry out its biological action in cooperation with other neuropeptides, such as CRH, and blocking its receptor NTSR-1 on MCs could be sufficient to improve some neurological diseases. (42). Moreover, there is a relationship between dopamine and NTS. In fact, it has been reported that dopamine receptor-2 signaling is capable of modulating the release of NTS (7). This data has been confirmed, as blocking the dopamine receptor-2 leads to a reduction in the secretion of NTS at an extracellular level (43).
These biological effects allow us to better understand the dopamine/NTS interaction in inflammatory neurological diseases where these neurotransmitters are involved. Theoharides reports in his experiments that young children affected by ASD present a neuroimmune dysfunction where NTS is increased and proposes that for this, NTS could constitute an interesting therapeutic target (44). By binding to its receptors, NTS stimulates MCs in rats to produce more histamine, increasing its plasma levels and vascular permeability (44). This author also reports that by stimulating the secretion of MCs, NTS also increases endothelial growth factor (EGF) and plasma histamine levels (45). Taken together, these results indicate that NTS could stimulate the immune system in cooperation with MCs, with effects on CNS inflammation (41).
CONCLUSIONS
In conclusion, the secretion NTS activates MCs through the it’s receptors to release pro-inflammatory compounds with consequent inflammation of the CNS. Therefore, NTS could be targeted as a new therapeutic option for treating neurological pathologies.
Conflict of interest
The author declares that they have no conflict of interest.
REFERENCES
- Carraway R, Leeman SE. The synthesis of neurotensin. Journal of Biological Chemistry. 1975;250(5):1912-1918. doi:https://doi.org/10.1016/s0021-9258(19)41781-x
- Slosky LM, Bai Y, Toth K, et al. β-Arrestin-Biased Allosteric Modulator of NTSR1 Selectively Attenuates Addictive Behaviors. Cell. 2020;181(6):1364-1379.e14. doi:https://doi.org/10.1016/j.cell.2020.04.053
- Tang KH, Ma S, Lee TK, et al. CD133+ liver tumor-initiating cells promote tumor angiogenesis, growth, and self-renewal through neurotensin/interleukin-8/CXCL1 signaling. Hepatology. 2012;55(3):807-820. doi:https://doi.org/10.1002/hep.24739
- Nemeroff CB, Osbahr AJ, Manberg PJ, Ervin GN, Prange AJ. Alterations in nociception and body temperature after intracisternal administration of neurotensin, beta-endorphin, other endogenous peptides, and morphine. Proceedings of the National Academy of Sciences of the United States of America. 1979;76(10):5368-5371. doi:https://doi.org/10.1073/pnas.76.10.5368
- López-Muñoz F, Álamo C. Neurobiological Background for the Development of New Drugs in Schizophrenia. Clinical Neuropharmacology. 2011;34(3):111-126. doi:https://doi.org/10.1097/wnf.0b013e318215c2f7
- Eiselt E, Côté J, Longpré JM, Blais V, Sarret P, Gendron L. The combination of opioid and neurotensin receptor agonists improves their analgesic/adverse effect ratio. European journal of pharmacology. 2019;848:80-87. doi:https://doi.org/10.1016/j.ejphar.2019.01.048
- Ferraro L, Beggiato S, Borroto-Escuela D, et al. Neurotensin NTS1-Dopamine D2 Receptor-Receptor Interactions in Putative Receptor Heteromers: Relevance for Parkinson’s Disease and Schizophrenia. Current Protein & Peptide Science. 2014;15(7):681-690. doi:https://doi.org/10.2174/1389203715666140901105253
- Rømer TB, Jeppesen R, Christensen B, Benros ME. Biomarkers in the cerebrospinal fluid of patients with psychotic disorders compared to healthy controls: a systematic review and meta-analysis. Molecular psychiatry. 2023;28(6):2277-2290. doi:https://doi.org/10.1038/s41380-023-02059-2
- Nicoli CD, Long DL, Plante TB, et al. Pro-neurotensin/Neuromedin N and Hypertension Risk: A Prospective Study. American journal of hypertension. 2021;35(3):281-288. doi:https://doi.org/10.1093/ajh/hpab166
- Kislauskis EH, Bullock BP, McNeil S, Dobner PR. The rat gene encoding neurotensin and neuromedin N. Structure, tissue-specific expression, and evolution of exon sequences. Journal of Biological Chemistry. 1988;263(10):4963-4968. doi:https://doi.org/10.1016/s0021-9258(18)68881-7
- Spokes RA, Lee YC, Yiangou Y, Domin J, Bloom SR. Comparison of neuromedin-N and neurotensin on net fluid flux across rat small intestine. European journal of pharmacology. 1990;175(1):43-47. doi:https://doi.org/10.1016/0014-2999(90)90150-5
- Béraud-Dufour S, Devader C, Massa F, Roulot M, Coppola T, Mazella J. Focal Adhesion Kinase-Dependent Role of the Soluble Form of Neurotensin Receptor-3/Sortilin in Colorectal Cancer Cell Dissociation. International journal of molecular sciences. 2016;17(11):1860-1860. doi:https://doi.org/10.3390/ijms17111860
- Kitabgi P. Prohormone convertases differentially process pro-neurotensin/neuromedin N in tissues and cell lines. Journal of molecular medicine. 2006;84(8):628-634. doi:https://doi.org/10.1007/s00109-006-0044-6
- Evers BM, Wang X, Zhou Z, Townsend CM, McNeil GP, Dobner PR. Characterization of Promoter Elements Required for Cell-Specific Expression of the Neurotensin/Neuromedin N Gene in a Human Endocrine Cell Line. Molecular and cellular biology. 1995;15(7):3870-3881. doi:https://doi.org/10.1128/mcb.15.7.3870
- Vincent JP, Mazella J, Kitabgi P. Neurotensin and neurotensin receptors. Trends in Pharmacological Sciences. 1999;20(7):302-309. doi:https://doi.org/10.1016/s0165-6147(99)01357-7
- Li Z, Liang Y, Boules M, Gordillo A, Richelson E. Effect of amphetamine on extracellular concentrations of amino acids in striatum in neurotensin subtype 1 and 2 receptor null mice: A possible interaction between neurotensin receptors and amino acid systems for study of schizophrenia. Neuropharmacology. 2010;58(7):1174-1178. doi:https://doi.org/10.1016/j.neuropharm.2010.02.016
- Driessen TM, Zhao C, Whittlinger A, Williams H, Gammie SC. Endogenous CNS Expression of Neurotensin and Neurotensin Receptors Is Altered during the Postpartum Period in Outbred Mice. PLOS ONE. 2014;9(1):e83098-e83098. doi:https://doi.org/10.1371/journal.pone.0083098
- Tabarean I. Neurotensin induces hypothermia by activating both neuronal neurotensin receptor 1 and astrocytic neurotensin receptor 2 in the median preoptic nucleus. Neuropharmacology. 2020;171:108069. doi:https://doi.org/10.1016/j.neuropharm.2020.108069
- Faure MP, Labbé-Jullié C, Cashman N, Kitabgi P, Beaudet A. Binding and internalization of neurotensin in hybrid cells derived from septal cholinergic neurons. Synapse. 1995;20(2):106-116. doi:10.1002/syn.890200203
- Kleczkowska P, Lipkowski AW. Neurotensin and neurotensin receptors: Characteristic, structure–activity relationship and pain modulation—A review. European Journal of Pharmacology. 2013;716(1-3):54-60. doi:https://doi.org/10.1016/j.ejphar.2013.03.004
- Carraway RE, Mitra SP. Neurotensin enhances agonist-induced cAMP accumulation in PC3 cells via Ca2+-dependent adenylyl cyclase(s). Molecular and Cellular Endocrinology. 1998;144(1-2):47-57. doi:https://doi.org/10.1016/s0303-7207(98)00154-3
- Sarret P, Esdaile MJ, Perron A, Martinez J, Stroh T, Beaudet A. Potent spinal analgesia elicited through stimulation of NTS2 neurotensin receptors. The Journal of Neuroscience. 2005;25(36):8188-8196. doi:10.1523/JNEUROSCI.0810-05.2005
- Ramirez‐Virella J, Leinninger GM. The Role of Central Neurotensin in Regulating Feeding and Body Weight. Endocrinology. 2021;162(5). doi:https://doi.org/10.1210/endocr/bqab038
- Wilson C, Naves T, Saada S, et al. The Implications of Sortilin/Vps10p Domain Receptors in Neurological and Human Diseases. CNS & Neurological Disorders – Drug Targets. 2014;13(8):1354-1365. doi:https://doi.org/10.2174/1871527313666141023151642
- Gilliam-Vigh H, Jorsal T, Nielsen SW, et al. Expression of Neurotensin and Its Receptors Along the Intestinal Tract in Type 2 Diabetes Patients and Healthy Controls. The Journal of clinical endocrinology and metabolism/Journal of clinical endocrinology & metabolism. 2023;108(9):2211-2216. doi:https://doi.org/10.1210/clinem/dgad146
- Barchetta I, Riccieri V, Vasile M, et al. High prevalence of capillary abnormalities in patients with diabetes and association with retinopathy. Diabetic medicine. 2011;28(9):1039-1044. doi:https://doi.org/10.1111/j.1464-5491.2011.03325.x
- Li J, Song J, Zaytseva YY, et al. An obligatory role for neurotensin in high-fat-diet-induced obesity. Nature. 2016;533(7603):411-415. doi:https://doi.org/10.1038/nature17662
- Pereira da Silva L, Miguel Neves B, Moura L, Cruz MT, Carvalho E. Neurotensin Decreases the Proinflammatory Status of Human Skin Fibroblasts and Increases Epidermal Growth Factor Expression. International journal of inflammation. 2014;2014:1-9. doi:https://doi.org/10.1155/2014/248240
- Mishra A, Singh KP. Protective effect of neurotensin receptor-1 agonist PD 149163 against lipopolysaccharide-induced gut toxicity in mice. Drug and chemical toxicology. 2021;45(6):2399-2410. doi:https://doi.org/10.1080/01480545.2021.1954698
- Redegeld FA, Yu Y, Kumari S, Charles N, Blank U. Non-IgE mediated mast cell activation. Immunological Reviews. 2018;282(1):87-113. doi:https://doi.org/10.1111/imr.12629
- Galli SJ, Kalesnikoff J, Grimbaldeston MA, Piliponsky AM, Williams CMM, Tsai M. mast cells as “tunable” effector and immunoregulatory cells: Recent Advances. Annual Review of Immunology. 2005;23(1):749-786. doi:https://doi.org/10.1146/annurev.immunol.21.120601.141025
- Alysandratos K, Asadi S, Angelidou A, et al. Neurotensin and CRH Interactions Augment Human Mast Cell Activation. Doherty TM, ed. PLoS ONE. 2012;7(11):e48934. doi:https://doi.org/10.1371/journal.pone.0048934
- Vasiadi M, Therianou A, Alysandratos KD, et al. Serum neurotensin (NT) is increased in psoriasis and NT induces vascular endothelial growth factor release from human mast cells. British Journal of Dermatology. 2012;166(6):1349-1352. doi:https://doi.org/10.1111/j.1365-2133.2012.10843.x
- Theoharides TC. The impact of psychological stress on mast cells. Annals of Allergy, Asthma & Immunology: Official Publication of the American College of Allergy, Asthma, & Immunology. 2020;125(4):388-392. doi:https://doi.org/10.1016/j.anai.2020.07.007
- Barrocas AM, Cochrane DE, Carraway RE, Feldberg RS. Neurotensin stimulation of mast cell secretion is receptor-mediated, pertussis-toxin sensitive and requires activation of phospholipase C. Immunopharmacology. 1999;41(2):131-137. doi:https://doi.org/10.1016/s0162-3109(98)00064-2
- Singh LK, Pang X, Alexacos N, Letourneau R, Theoharides TC. Acute Immobilization Stress Triggers Skin Mast Cell Degranulation via Corticotropin Releasing Hormone, Neurotensin, and Substance P: A Link to Neurogenic Skin Disorders. Brain, Behavior, and Immunity. 1999;13(3):225-239. doi:https://doi.org/10.1006/brbi.1998.0541
- Martin S, Vincent JP, Mazella J. Involvement of the Neurotensin Receptor-3 in the Neurotensin-Induced Migration of Human Microglia. The journal of neuroscience/ The Journal of neuroscience. 2003;23(4):1198-1205. doi:https://doi.org/10.1523/jneurosci.23-04-01198.2003
- Mishra A, Singh KP. Neurotensin agonist PD 149163 modulates the neuroinflammation induced by bacterial endotoxin lipopolysaccharide in mice model. Immunopharmacology and immunotoxicology. 2022;44(2):216-226. doi:https://doi.org/10.1080/08923973.2022.2037628
- Donelan J, Boucher W, Papadopoulou N, et al. Corticotropin-releasing hormone induces skin vascular permeability through a neurotensin-dependent process. Proceedings of the National Academy of Sciences. 2006;103(20):7759-7764. doi:https://doi.org/10.1073/pnas.0602210103
- Theoharides TC, Donelan JM, Papadopoulou N, Cao J, Kempuraj D, Conti P. Mast cells as targets of corticotropin-releasing factor and related peptides. Trends in Pharmacological Sciences. 2004;25(11):563-568. doi:https://doi.org/10.1016/j.tips.2004.09.007
- Angelidou A, Francis K, Vasiadi M, et al. Neurotensin is increased in serum of young children with autistic disorder. Journal of Neuroinflammation. 2010;7(1). doi:https://doi.org/10.1186/1742-2094-7-48
- Theoharides TC, Donelan J, Kandere-Grzybowska K, Konstantinidou A. The role of mast cells in migraine pathophysiology. Brain Research Reviews. 2005;49(1):65-76. doi:https://doi.org/10.1016/j.brainresrev.2004.11.006
- Fawaz CS, Martel P, Leo D, Trudeau LE. Presynaptic action of neurotensin on dopamine release through inhibition of D2 receptor function. BMC Neuroscience. 2009;10(1):96. doi:https://doi.org/10.1186/1471-2202-10-96
- Theoharides TC. Is a subtype of autism an allergy of the brain? Clinical Therapeutics. 2013;35(5):584-591. doi:https://doi.org/10.1016/j.clinthera.2013.04.009
- Theoharides TC, Stewart JM, Taracanova A, Conti P, Zouboulis CC. Neuroendocrinology of the skin. Reviews in Endocrine & Metabolic Disorders. 2016;17(3):287-294. doi:https://doi.org/10.1007/s11154-016-9369-9