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1.
Biol Psychiatry ; 95(8): 785-799, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38952926

RESUMO

Background: Responding to social signals by expressing the correct behavior is not only challenged in autism, but also in diseases with high prevalence of autism, like Prader-Willi Syndrome (PWS). Clinical evidence suggests aberrant pro-social behavior in patients can be regulated by intranasal oxytocin (OXT) or vasopressin (AVP). However, what neuronal mechanisms underlie impaired behavioral responses in a socially-aversive context, and how can they be corrected, remains largely unknown. Methods: Using the Magel2 knocked-out (KO) mouse model of PWS (crossed with CRE-dependent transgenic lines), we devised optogenetic, physiological and pharmacological strategies in a social-fear-conditioning paradigm. Pathway specific roles of OXT and AVP signaling were investigated converging on the lateral septum (LS), a region which receives dense hypothalamic inputs. Results: OXT and AVP signaling promoted inhibitory synaptic transmission in the LS, which failure in Magel2KO mice disinhibited somatostatin (SST) neurons and disrupted social-fear extinction. The source of OXT and AVP deficits mapped specifically in the supraoptic nucleus→LS pathway of Magel2KO mice disrupting social-fear extinction, which could be corrected by optogenetic or pharmacological inhibition of SST-neurons in the LS. Interestingly, LS SST-neurons also gated the expression of aggressive behavior, possibly as part of functional units operating beyond local septal circuits. Conclusions: SST cells in the LS play a crucial role in integration and expression of disrupted neuropeptide signals in autism, thereby altering the balance in expression of safety versus fear. Our results uncover novel mechanisms underlying dysfunction in a socially-aversive context, and provides a new framework for future treatments in autism-spectrum disorders.


Assuntos
Modelos Animais de Doenças , Extinção Psicológica , Medo , Camundongos Knockout , Neurônios , Ocitocina , Síndrome de Prader-Willi , Somatostatina , Vasopressinas , Animais , Ocitocina/farmacologia , Somatostatina/farmacologia , Somatostatina/metabolismo , Medo/efeitos dos fármacos , Medo/fisiologia , Extinção Psicológica/efeitos dos fármacos , Extinção Psicológica/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Camundongos , Síndrome de Prader-Willi/fisiopatologia , Síndrome de Prader-Willi/tratamento farmacológico , Vasopressinas/metabolismo , Agressão/efeitos dos fármacos , Agressão/fisiologia , Masculino , Comportamento Social , Núcleos Septais/efeitos dos fármacos , Núcleos Septais/metabolismo , Optogenética , Camundongos Endogâmicos C57BL , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Intrinsicamente Desordenadas
2.
Front Endocrinol (Lausanne) ; 15: 1385079, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948517

RESUMO

Background: 177Lu-oxodotreotide peptide receptor therapy (LuPRRT) is an efficient treatment for midgut neuroendocrine tumors (NETs) of variable radiological response. Several clinical, biological, and imaging parameters may be used to establish a relative disease prognosis but none is able to predict early efficacy or toxicities. We investigated expression levels for mRNA and miRNA involved in radiosensitivity and tumor progression searching for correlations related to patient outcome during LuPRRT therapy. Methods: Thirty-five patients received LuPRRT for G1/G2 midgut NETs between May 2019 and September 2021. Peripheral blood samples were collected prior to irradiation, before and 48 h after the second and the fourth LuPRRT, and at 6-month follow-up. Multiple regression analyses and Pearson correlations were performed to identify the miRNA/mRNA signature that will best predict response to LuPRRT. Results: Focusing on four mRNAs and three miRNAs, we identified a miRNA/mRNA signature enabling the early identification of responders to LuPRRT with significant reduced miRNA/mRNA expression after the first LuPRRT administration for patients with progressive disease at 1 year (p < 0.001). The relevance of this signature was reinforced by studying its evolution up to 6 months post-LuPRRT. Moreover, nadir absolute lymphocyte count within the first 2 months after the first LuPRRT administration was significantly related to low miRNA/mRNA expression level (p < 0.05) for patients with progressive disease. Conclusion: We present a pilot study exploring a miRNA/mRNA signature that correlates with early hematologic toxicity and therapeutic response 12 months following LuPRRT. This signature will be tested prospectively in a larger series of patients.


Assuntos
Neoplasias Intestinais , MicroRNAs , Tumores Neuroendócrinos , RNA Mensageiro , Humanos , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/sangue , Tumores Neuroendócrinos/terapia , Tumores Neuroendócrinos/radioterapia , Tumores Neuroendócrinos/patologia , Masculino , Feminino , MicroRNAs/sangue , MicroRNAs/genética , Pessoa de Meia-Idade , Neoplasias Intestinais/sangue , Neoplasias Intestinais/patologia , Neoplasias Intestinais/genética , Neoplasias Intestinais/tratamento farmacológico , RNA Mensageiro/genética , RNA Mensageiro/sangue , Idoso , Seguimentos , Adulto , Prognóstico , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Receptores de Peptídeos/genética , Compostos Radiofarmacêuticos/uso terapêutico , Compostos Radiofarmacêuticos/administração & dosagem , Lutécio , Radioisótopos
3.
Front Endocrinol (Lausanne) ; 15: 1302672, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974572

RESUMO

Somatostatin (SST) plays diverse physiological roles in vertebrates, particularly in regulating growth hormone secretion from the pituitary. While the function of SST as a neuromodulator has been studied extensively, its role in fish and mammalian reproduction remains poorly understood. To address this gap, we investigated the involvement of the somatostatin system in the regulation of growth and reproductive hormones in tilapia. RNA sequencing of mature tilapia brain tissue revealed the presence of three SST peptides: SST6, SST3, and low levels of SST1. Four different isoforms of the somatostatin receptor (SSTR) subfamily were also identified in the tilapia genome. Phylogenetic and synteny analysis identified tiSSTR2-like as the root of the tree, forming two mega clades, with SSTR1 and SSTR4 in one and SSTR2a, SSTR3a, and SSTR5b in the other. Interestingly, the tiSSTR-5 isoforms 5x1, 5x2, and 5x3 were encoded in the sstr3b gene and were an artifact of misperception in the nomenclature in the database. RNA-seq of separated pituitary cell populations showed that SSTRs were expressed in gonadotrophs, with sstr3a enriched in luteinizing hormone (LH) cells and sstr3b significantly enriched in follicle-stimulating hormone (FSH) cells. Notably, cyclosomatostatin, an SSTR antagonist, induced cAMP activity in all SSTRs, with SSTR3a displaying the highest response, whereas octreotide, an SSTR agonist, showed a binding profile like that observed in human receptors. Binding site analysis of tiSSTRs from tilapia pituitary cells revealed the presence of canonical binding sites characteristic of peptide-binding class A G-protein-coupled receptors. Based on these findings, we explored the effect of somatostatin on gonadotropin release from the pituitary in vivo. Whereas cyclosomatostatin increased LH and FSH plasma levels at 2 h post-injection, octreotide decreased FSH levels after 2 h, but the LH levels remained unaffected. Overall, our findings provide important insights into the somatostatin system and its mechanisms of action, indicating a potential role in regulating growth and reproductive hormones. Further studies of the complex interplay between SST, its receptors, and reproductive hormones may advance reproductive control and management in cultured populations.


Assuntos
Filogenia , Receptores de Somatostatina , Reprodução , Somatostatina , Tilápia , Animais , Tilápia/metabolismo , Tilápia/crescimento & desenvolvimento , Receptores de Somatostatina/metabolismo , Receptores de Somatostatina/genética , Somatostatina/metabolismo , Reprodução/fisiologia , Hipófise/metabolismo , Humanos , Feminino , Masculino
4.
Int J Mol Sci ; 25(13)2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-39000000

RESUMO

Somatostatin (SS) plays crucial regulatory roles in animal growth and reproduction by affecting the synthesis and secretion of growth hormone (GH). However, the mechanism by which SS regulates growth and development in goats is still unclear. In order to investigate the regulatory networks of the hypothalamus and pituitary in goats affected by SS DNA vaccines, in this study, we used a previously established oral attenuated Salmonella typhimurium SS DNA vaccine, X9241 (ptCS/2SS-asd), to treat wethers. We analyzed the protein changes in hypothalamic and pituitary tissues using a TMT-based proteomics approach. Additionally, we examined the metabolic profiles of the serum of control and immunized wethers through untargeted metabolomics using liquid chromatography-mass spectrometry (LC-MS). Key signaling pathways were identified based on differentially expressed metabolites (DEMs) and differentially expressed proteins (DEPs). Furthermore, the effect of critical DEPs on signaling pathways was confirmed through Western blotting (WB) experiments, which elucidated the mechanism of active SS immunization in wethers. A proteomics analysis revealed that the expression of 58 proteins in the hypothalamus and 124 in the pituitary gland was significantly altered following SS vaccine treatment (fold change > 1.2 or < 0.83, p < 0.05). In the hypothalamus, many DEPs were associated with gene ontology (GO) terms related to neuronal signaling. In contrast, most DEPs were associated with metabolic pathways. In the pituitary gland, the DEPs were largely related to immune and nutrient metabolism functions, with significant enrichment in KEGG pathways, particularly those involving the metabolic pathway, sphingolipid signaling, and the cGMP-PKG signaling pathway. A metabolomic analysis further showed that active SS immunization in wethers led to significant alterations in seven serum metabolites. Notably, the sphingolipid signaling pathway, secondary bile acid synthesis, sphingolipid metabolism, and lysine synthesis were significantly disrupted. SS vaccines induced marked changes in hypothalamic-pituitary proteins in wethers, facilitating alterations in their growth processes. This study not only provides insights into the mechanism of the SS gene in regulating GH secretion in wethers but also establishes a basis for hormone immunoregulation technology to enhance livestock production performance.


Assuntos
Cabras , Hipotálamo , Hipófise , Proteômica , Somatostatina , Vacinas de DNA , Animais , Somatostatina/metabolismo , Proteômica/métodos , Hipotálamo/metabolismo , Vacinas de DNA/imunologia , Hipófise/metabolismo , Metabolômica/métodos , Transdução de Sinais , Metaboloma
5.
Dtsch Med Wochenschr ; 149(15): 871-878, 2024 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-39013407

RESUMO

Despite, or perhaps because of the rarity of neuroendocrine neoplasms, the diagnosis and treatment of these malignancies is of particular importance. Nuclear medicine can make an important contribution to this challenge. It offers the most sensitive and specific imaging of these tumor entities and can be helpful in treatment due to the radiotherapeutic drugs that have recently been approved. This theragnostic (fusion of therapeutic and diagnostic) concept is based on the frequent overexpression of somatostatin receptors on neuroendocrine tumor cells.Using diagnostic and therapeutic pharmaceuticals based on analogues from somatostatin, most applications from the nuclear medicine are successful, an additional therapeutic method is SIRT, also known as TARE, in which the hypervascularization of NEN-metastases is used as a therapeutic target.


Assuntos
Tumores Neuroendócrinos , Humanos , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/terapia , Medicina Nuclear/métodos , Compostos Radiofarmacêuticos/uso terapêutico , Receptores de Somatostatina , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico
6.
Life Sci ; 351: 122854, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38901688

RESUMO

AIMS: To evaluate the cell proliferation and death, and structural morphology of the pancreatic islet cells of the rats with hyperglycemia in the first month of life and compare to those of the control rats. MAIN METHODS: Female Sprague-Dawley newborn rats received Streptozotocin (a beta-cytotoxic drug) at birth for diabetes induction. Control and hyperglycemic animals were euthanized on different days of life: 5, 10, 15, and 30. The pancreas was collected and processed for immunohistochemical analysis of cleaved Caspase-3 (cell death), Ki-67 (cell proliferation), PDX-1 (transcription factor responsible for insulin synthesis), and endocrine hormones (insulin, glucagon, and somatostatin). KEY FINDINGS: Control females showed a higher percentage (%) of Ki-67-positive(+) cells on D10 and D15, a higher % of insulin+ and somatostatin+ cells on D15 and D30, a lower % of PDX-1+ cells on D10, and a higher % of glucagon+ cells on D10 and D30. Hyperglycemic females showed a lower % of Ki-67+ cells on D15, a higher % of cleaved Caspase-3+ cells on D15, and insulin+ cells on D15 and D30. In the comparison among the experimental groups, the hyperglycemic females showed an increased % of cleaved Caspase-3+ and Ki-67+ cells and a lower % of PDX-1+ cells. SIGNIFICANCE: This study enabled a better understanding of the abnormal pancreas development regarding cellular proliferation, apoptosis, and hormonal synthesis in the neonatal period. Thus, the pancreatic islets of hyperglycemic rats do not reestablish the normal endocrine cell population, and cellular apoptosis overcame the proliferative activity of these cells.


Assuntos
Animais Recém-Nascidos , Proliferação de Células , Hiperglicemia , Ilhotas Pancreáticas , Ratos Sprague-Dawley , Animais , Feminino , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Ratos , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/metabolismo , Morte Celular , Glucagon/metabolismo , Insulina/metabolismo , Antígeno Ki-67/metabolismo , Caspase 3/metabolismo , Somatostatina/metabolismo , Apoptose , Transativadores , Proteínas de Homeodomínio
7.
Proc Natl Acad Sci U S A ; 121(26): e2321710121, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38885377

RESUMO

Somatostatin receptor 5 (SSTR5) is an important G protein-coupled receptor and drug target for neuroendocrine tumors and pituitary disorders. This study presents two high-resolution cryogenicelectron microscope structures of the SSTR5-Gi complexes bound to the cyclic neuropeptide agonists, cortistatin-17 (CST17) and octreotide, with resolutions of 2.7 Å and 2.9 Å, respectively. The structures reveal that binding of these peptides causes rearrangement of a "hydrophobic lock", consisting of residues from transmembrane helices TM3 and TM6. This rearrangement triggers outward movement of TM6, enabling Gαi protein engagement and receptor activation. In addition to hydrophobic interactions, CST17 forms conserved polar contacts similar to somatostatin-14 binding to SSTR2, while further structural and functional analysis shows that extracellular loops differently recognize CST17 and octreotide. These insights elucidate agonist selectivity and activation mechanisms of SSTR5, providing valuable guidance for structure-based drug development targeting this therapeutically relevant receptor.


Assuntos
Octreotida , Receptores de Somatostatina , Receptores de Somatostatina/metabolismo , Receptores de Somatostatina/agonistas , Receptores de Somatostatina/química , Humanos , Octreotida/química , Octreotida/farmacologia , Octreotida/metabolismo , Neuropeptídeos/metabolismo , Neuropeptídeos/química , Microscopia Crioeletrônica , Ligação Proteica , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/metabolismo , Somatostatina/metabolismo , Somatostatina/química , Somatostatina/análogos & derivados , Modelos Moleculares , Células HEK293
8.
Org Lett ; 26(26): 5447-5452, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38896796

RESUMO

Interest in electrocatalytic bioconjugation reactions has surged, particularly for modifying tryptophan and tyrosine residues in proteins. We used a cost-effective graphite felt electrode and low-current methodology to achieve selective bioconjugation of tryptophan with thiophenols, yielding up to 92%. This method exclusively labeled tryptophan residues and incorporated fluorinated tryptophan for NMR analysis. Eight polypeptides, including lanreotide and leuprorelin, were effectively coupled, demonstrating the method's versatility and potential for novel diagnostic and therapeutic agents.


Assuntos
Peptídeos , Triptofano , Triptofano/química , Peptídeos/química , Técnicas Eletroquímicas , Estrutura Molecular , Somatostatina/química , Somatostatina/análogos & derivados , Peptídeos Cíclicos/química , Eletrodos
9.
Nat Commun ; 15(1): 5421, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926335

RESUMO

During brain development, neural circuits undergo major activity-dependent restructuring. Circuit wiring mainly occurs through synaptic strengthening following the Hebbian "fire together, wire together" precept. However, select connections, essential for circuit development, are transient. They are effectively connected early in development, but strongly diminish during maturation. The mechanisms by which transient connectivity recedes are unknown. To investigate this process, we characterize transient thalamocortical inputs, which depress onto somatostatin inhibitory interneurons during development, by employing optogenetics, chemogenetics, transcriptomics and CRISPR-based strategies in mice. We demonstrate that in contrast to typical activity-dependent mechanisms, transient thalamocortical connectivity onto somatostatin interneurons is non-canonical and involves metabotropic signaling. Specifically, metabotropic-mediated transcription, of guidance molecules in particular, supports the elimination of this connectivity. Remarkably, we found that this process impacts the development of normal exploratory behaviors of adult mice.


Assuntos
Interneurônios , Somatostatina , Tálamo , Animais , Interneurônios/metabolismo , Somatostatina/metabolismo , Somatostatina/genética , Camundongos , Tálamo/metabolismo , Optogenética , Transdução de Sinais , Masculino , Córtex Cerebral/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/crescimento & desenvolvimento , Feminino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
11.
Expert Opin Drug Saf ; 23(8): 949-957, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38847075

RESUMO

INTRODUCTION: Neuroendocrine neoplasms (NENs) are a rare group of tumors originating from neuroendocrine cells in various organs. They include neuroendocrine tumors (NETs) and neuroendocrine carcinomas (NECs), which differ in biological behavior and prognosis. NETs are usually well-differentiated and slow-growing, while NECs are poorly differentiated and more aggressive. Management of NETs often involves somatostatin analogs like octreotide and lanreotide to control tumor growth and alleviate symptoms, especially in well-differentiated NETs. Lanreotide is used to control tumor growth, and both lanreotide and octreotide alleviate symptoms. Treatment approaches may vary depending on the specific type and grade of the neuroendocrine neoplasm. AREAS COVERED: This review provides an update on the safety of lanreotide autogel in treating patients with NETs, through a comprehensive review of clinical trials, post-marketing surveillance, real-world evidence, and its safety profile. Specific adverse events, side effects, and potential risks associated with lanreotide autogel are discussed, along with risk mitigation strategies and recommendations for patient monitoring. EXPERT OPINION: The findings highlight the overall safety of lanreotide autogel in managing NETs, focusing on its efficacy in controlling hormone secretion, tumor progression, and symptom management. New safety concerns and precautions are also addressed to help healthcare providers make informed decisions when prescribing lanreotide autogel.


Assuntos
Antineoplásicos , Tumores Neuroendócrinos , Peptídeos Cíclicos , Somatostatina , Humanos , Somatostatina/análogos & derivados , Somatostatina/administração & dosagem , Somatostatina/efeitos adversos , Peptídeos Cíclicos/administração & dosagem , Peptídeos Cíclicos/efeitos adversos , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/patologia , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Carcinoma Neuroendócrino/tratamento farmacológico , Carcinoma Neuroendócrino/patologia , Géis , Progressão da Doença
12.
Protein Expr Purif ; 222: 106537, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38944221

RESUMO

Peptides are used for diagnostics, therapeutics, and as antimicrobial agents. Most peptides are produced by chemical synthesis, but recombinant production has recently become an attractive alternative due to the advantages of high titers, less toxic waste and correct folding of tertiary structure. Somatostatin-28 is a peptide hormone that regulates the endocrine system, cell proliferation and inhibits the release of numerous secondary hormones in human body. It is composed of 28 amino acids and has one disulfide bond, which makes it to an optimal model peptide for a whole downstream purification process. We produced the peptide in the periplasm of E. coli using the CASPON™ technology, an affinity fusion technology system that enables high soluble expression of recombinant proteins and cleaves the fusion tag with a circularly permuted human caspase-2. Furthermore, purification of the products is straight forward using an established platform process. Two different case studies for downstream purification are presented, starting with either hydrochloric acid or polyethyleneimine as an extraction aid. After release of affinity-tagged somatostatin-28 out of E. coli's periplasm, several purification steps were performed, delivering a pure peptide solution after the final polishing step. The process was monitored by reversed-phase high-performance liquid chromatography as well as mass spectrometry to determine the yield and correct disulfide bond formation. Monitoring of impurities like host cell proteins, DNA and endotoxins after each downstream unit confirmed effective removal for both purification pathways.


Assuntos
Escherichia coli , Ácido Clorídrico , Polietilenoimina , Somatostatina , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Somatostatina/química , Somatostatina/genética , Somatostatina/isolamento & purificação , Ácido Clorídrico/química , Polietilenoimina/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/biossíntese
13.
Sci Rep ; 14(1): 13525, 2024 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866945

RESUMO

The traditional nomenclature of enteroendocrine cells (EECs), established in 1977, applied the "one cell - one hormone" dogma, which distinguishes subpopulations based on the secretion of a specific hormone. These hormone-specific subpopulations included S cells for secretin (SCT), K cells for glucose-dependent insulinotropic polypeptide (GIP), N cells producing neurotensin (NTS), I cells producing cholecystokinin (CCK), D cells producing somatostatin (SST), and others. In the past 15 years, reinvestigations into murine and human organoid-derived EECs, however, strongly questioned this dogma and established that certain EECs coexpress multiple hormones. Using the Gut Cell Atlas, the largest available single-cell transcriptome dataset of human intestinal cells, this study consolidates that the original dogma is outdated not only for murine and human organoid-derived EECs, but also for primary human EECs, showing that the expression of certain hormones is not restricted to their designated cell type. Moreover, specific analyses into SCT-expressing cells reject the presence of any cell population that exhibits significantly elevated secretin expression compared to other cell populations, previously referred to as S cells. Instead, this investigation indicates that secretin production is realized jointly by other enteroendocrine subpopulations, validating corresponding observations in murine EECs also for human EECs. Furthermore, our findings corroborate that SCT expression peaks in mature EECs, in contrast, progenitor EECs exhibit markedly lower expression levels, supporting the hypothesis that SCT expression is a hallmark of EEC maturation.


Assuntos
Células Enteroendócrinas , Perfilação da Expressão Gênica , Secretina , Análise de Célula Única , Humanos , Células Enteroendócrinas/metabolismo , Secretina/metabolismo , Secretina/genética , Análise de Célula Única/métodos , Camundongos , Animais , Transcriptoma , Diferenciação Celular , Organoides/metabolismo , Organoides/citologia , Colecistocinina/metabolismo , Colecistocinina/genética , Somatostatina/metabolismo , Somatostatina/genética , Análise da Expressão Gênica de Célula Única
14.
Int J Nanomedicine ; 19: 4977-4994, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828204

RESUMO

Purpose: Exosomes are membrane vesicles secreted by various cells and play a crucial role in intercellular communication. They can be excellent delivery vehicles for oligonucleotide drugs, such as microRNAs, due to their high biocompatibility. MicroRNAs have been shown to be more stable when incorporated into exosomes; however, the lack of targeting and immune evasion is still the obstacle to the use of these microRNA-containing nanocarriers in clinical settings. Our goal was to produce functional exosomes loaded with target ligands, immune evasion ligand, and oligonucleotide drug through genetic engineering in order to achieve more precise medical effects. Methods: To address the problem, we designed engineered exosomes with exogenous cholecystokinin (CCK) or somatostatin (SST) as the targeting ligand to direct the exosomes to the brain, as well as transduced CD47 proteins to reduce the elimination or phagocytosis of the targeted exosomes. MicroRNA-29b-2 was the tested oligonucleotide drug for delivery because our previous research showed that this type of microRNA was capable of reducing presenilin 1 (PSEN1) gene expression and decreasing the ß-amyloid accumulation for Alzheimer's disease (AD) in vitro and in vivo. Results: The engineered exosomes, containing miR29b-2 and expressing SST and CD47, were produced by gene-modified dendritic cells and used in the subsequent experiments. In comparison with CD47-CCK exosomes, CD47-SST exosomes showed a more significant increase in delivery efficiency. In addition, CD47-SST exosomes led to a higher delivery level of exosomes to the brains of nude mice when administered intravenously. Moreover, it was found that the miR29b-2-loaded CD47-SST exosomes could effectively reduce PSEN1 in translational levels, which resulted in an inhibition of beta-amyloid oligomers production both in the cell model and in the 3xTg-AD animal model. Conclusion: Our results demonstrated the feasibility of the designed engineered exosomes. The application of this exosomal nanocarrier platform can be extended to the delivery of other oligonucleotide drugs to specific tissues for the treatment of diseases while evading the immune system.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Encéfalo , Antígeno CD47 , Exossomos , MicroRNAs , Presenilina-1 , Receptores de Somatostatina , Animais , Exossomos/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , MicroRNAs/genética , MicroRNAs/administração & dosagem , Presenilina-1/genética , Encéfalo/metabolismo , Receptores de Somatostatina/genética , Receptores de Somatostatina/metabolismo , Peptídeos beta-Amiloides/metabolismo , Camundongos , Antígeno CD47/genética , Antígeno CD47/metabolismo , Somatostatina , Humanos , Modelos Animais de Doenças
15.
Zhongguo Zhong Yao Za Zhi ; 49(10): 2699-2709, 2024 May.
Artigo em Chinês | MEDLINE | ID: mdl-38812170

RESUMO

A systematic evaluation of the differences in the chemical composition and efficacy of the different forms of Galli Gigerii Endothelium Corneum(GGEC) was conducted based on modern analytical techniques and a functional dyspepsia(FD) rat model, which clarifies the material basis of the digestive efficacy of GGEC. Proteins, enzymes, polysaccharides, amino acids, and flavonoids in GGEC powder and decoction were determined respectively. The total protein of the powder and decoction was 0.06% and 0.65%, respectively, and the pepsin and amylase potency of the powder was 27.03 and 44.05 U·mg~(-1) respectively. The polysaccharide of the decoction was 0.03%, and there was no polysaccharide detected in the powder. The total L-type amino acids in the powder and decoction were 279.81 and 8.27 mg·g~(-1) respectively, and the total flavonoid content was 59.51 µg·g~(-1). Enzymes and flavonoids were not detected in the decoction. The powder significantly reduced nutrient paste viscosity, while the decoction and control group showed no significant reduction in nutrient paste viscosity. FD rat models were prepared by iodoacetamide gavage and irregular diet. The results showed that both powder and decoction significantly increased the gastric emptying effect, small intestinal propulsion rate, digestive enzymes activity, gastrin(GAS), motilin(MTL), ghrelin(GHRL) and reduced vasoactive intestinal peptide(VIP), 3-(2-ammo-nioethyl)-5-hydroxy-1H-indolium maleate(5-HT), and somatostatin(SST) content in rats(P<0.05, P<0.01). Comparison of GGEC decoction and powder administration between groups of the same dosage level showed that gastrointestinal propulsion and serum levels of GAS, GHRL, VIP, and SST in the powder group were significantly superior to those in the decoction and that the gastrointestinal propulsion, as well as serum levels of MTL, GAS, and GHRL were slightly higher than those of the decoction with two times its raw dose, and the serum levels of SST, 5-HT, and VIP in the powder group were slightly lower than those of the decoction with two times its raw dose. In conclusion, both decoction and powder have therapeutic effects on FD, but there is a significant difference between the two effects. Under the same dosage, the digestive efficacy of the powder is significantly better than that of the decoction, and the decoction needs to increase the dosage to compensate for the efficacy. It is hypothesized that the digestive efficacy of the GGEC has a duality, and the digestive active ingredients of the powder may include enzymes and L-type amino acids, while the decoction mainly relies on L-type amino acids to exert its efficacy. This study provides new evidence to investigate the digestive active substances of the GGEC and to improve the effectiveness of the drug in the clinic.


Assuntos
Dispepsia , Ratos Sprague-Dawley , Animais , Ratos , Masculino , Dispepsia/tratamento farmacológico , Dispepsia/fisiopatologia , Dispepsia/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Humanos , Flavonoides/química , Flavonoides/farmacologia , Motilina , Peptídeo Intestinal Vasoativo/metabolismo , Grelina , Somatostatina
16.
Nat Neurosci ; 27(7): 1318-1332, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38769153

RESUMO

Emotion recognition and the resulting responses are important for survival and social functioning. However, how socially derived information is processed for reliable emotion recognition is incompletely understood. Here, we reveal an evolutionarily conserved long-range inhibitory/excitatory brain network mediating these socio-cognitive processes. Anatomical tracing in mice revealed the existence of a subpopulation of somatostatin (SOM) GABAergic neurons projecting from the medial prefrontal cortex (mPFC) to the retrosplenial cortex (RSC). Through optogenetic manipulations and Ca2+ imaging fiber photometry in mice and functional imaging in humans, we demonstrate the specific participation of these long-range SOM projections from the mPFC to the RSC, and an excitatory feedback loop from the RSC to the mPFC, in emotion recognition. Notably, we show that mPFC-to-RSC SOM projections are dysfunctional in mouse models relevant to psychiatric vulnerability and can be targeted to rescue emotion recognition deficits in these mice. Our findings demonstrate a cortico-cortical circuit underlying emotion recognition.


Assuntos
Emoções , Córtex Pré-Frontal , Animais , Emoções/fisiologia , Córtex Pré-Frontal/fisiologia , Camundongos , Masculino , Humanos , Neurônios GABAérgicos/fisiologia , Vias Neurais/fisiologia , Somatostatina/metabolismo , Reconhecimento Psicológico/fisiologia , Camundongos Endogâmicos C57BL , Optogenética , Feminino , Giro do Cíngulo/fisiologia
17.
Neuron ; 112(12): 2031-2044.e7, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38754414

RESUMO

The patterns of synaptic connectivity and physiological properties of diverse neuron types are shaped by distinct gene sets. Our study demonstrates that, in the mouse forebrain, the transcriptional profiles of inhibitory GABAergic interneurons are regulated by Nr4a1, an orphan nuclear receptor whose expression is transiently induced by sensory experiences and is required for normal learning. Nr4a1 exerts contrasting effects on the local axonal wiring of parvalbumin- and somatostatin-positive interneurons, which innervate different subcellular domains of their postsynaptic partners. The loss of Nr4a1 activity in these interneurons results in bidirectional, cell-type-specific transcriptional switches across multiple gene families, including those involved in surface adhesion and repulsion. Our findings reveal that combinatorial synaptic organizing codes are surprisingly flexible and highlight a mechanism by which inducible transcription factors can influence neural circuit structure and function.


Assuntos
Neurônios GABAérgicos , Interneurônios , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Animais , Interneurônios/metabolismo , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/fisiologia , Camundongos , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Somatostatina/metabolismo , Somatostatina/genética , Parvalbuminas/metabolismo , Camundongos Knockout , Masculino , Sinapses/metabolismo
18.
Pituitary ; 27(3): 303-309, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38713317

RESUMO

INTRODUCTION: Skeletal fragility is a clinically relevant and not-reversible complication of acromegaly, involving around 30-40% of patients since the disease diagnosis. Few studies have investigated the effects on skeletal health of medical therapies for acromegaly. In this retrospective longitudinal monocentre study, we investigated the outcome of skeletal fragility in patients treated with Pasireotide Lar in combination with Pegvisomant (Pasi-Lar + Peg-V), also comparing those observed in patients treated with conventional therapies. RESULTS: We included 6 patients treated with Pasi-Lar + Peg-V, 5 patients treated with Peg-V in monotherapy (m-Peg-V), 16 patients treated with Peg-V plus first-generation somatostatin receptor ligands (fg-SRLs + Peg-V), 9 patients treated with Pasi-Lar. None of the patients treated with Pasi-Lar + Peg-V experienced worsening of spine and femoral bone mineral density (BMD) and incident vertebral fractures (i-VFs). Eight patients experienced i-VFs. The frequency of i-VFs was significantly lower in patients treated with the Pasi-Lar + Peg-V (0/8; 0%), as compared to those observed in m-Peg-V treated patients (4/8; 50%, p = 0.02). The frequency of i-VFs was slightly but not significantly higher in Pasi-Lar treated patients (1/8; 12.5% p = 0.6) and in fg-SRLs + Peg-V treated patients (3/8; 37.5% p = 0.364), concerning those treated with Pasi-Lar + Peg-V (0/8; 0%). I-VFs occurred more frequently in patients with higher GH levels at acromegaly diagnosis (p < 0.001), and in patients who experienced a BMD worsening (p = 0.005). CONCLUSION: Our preliminary data suggested that in conventional and multi-drug resistant acromegaly, the combination therapy Pasi-Lar + Peg-V may prevent the worsening of BMD and the occurrence of i-VFs. Prospective and translational studies should further validate these results and ascertain underlying physiopathology mechanisms.


Assuntos
Acromegalia , Densidade Óssea , Hormônio do Crescimento Humano , Somatostatina , Humanos , Acromegalia/tratamento farmacológico , Densidade Óssea/efeitos dos fármacos , Pessoa de Meia-Idade , Feminino , Masculino , Estudos Retrospectivos , Adulto , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Hormônio do Crescimento Humano/análogos & derivados , Projetos Piloto , Idoso , Estudos Longitudinais
19.
Acta Neuropathol ; 147(1): 80, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714540

RESUMO

GABAergic interneurons play a critical role in maintaining neural circuit balance, excitation-inhibition regulation, and cognitive function modulation. In tuberous sclerosis complex (TSC), GABAergic neuron dysfunction contributes to disrupted network activity and associated neurological symptoms, assumingly in a cell type-specific manner. This GABAergic centric study focuses on identifying specific interneuron subpopulations within TSC, emphasizing the unique characteristics of medial ganglionic eminence (MGE)- and caudal ganglionic eminence (CGE)-derived interneurons. Using single-nuclei RNA sequencing in TSC patient material, we identify somatostatin-expressing (SST+) interneurons as a unique and immature subpopulation in TSC. The disrupted maturation of SST+ interneurons may undergo an incomplete switch from excitatory to inhibitory GABAergic signaling during development, resulting in reduced inhibitory properties. Notably, this study reveals markers of immaturity specifically in SST+ interneurons, including an abnormal NKCC1/KCC2 ratio, indicating an imbalance in chloride homeostasis crucial for the postsynaptic consequences of GABAergic signaling as well as the downregulation of GABAA receptor subunits, GABRA1, and upregulation of GABRA2. Further exploration of SST+ interneurons revealed altered localization patterns of SST+ interneurons in TSC brain tissue, concentrated in deeper cortical layers, possibly linked to cortical dyslamination. In the epilepsy context, our research underscores the diverse cell type-specific roles of GABAergic interneurons in shaping seizures, advocating for precise therapeutic considerations. Moreover, this study illuminates the potential contribution of SST+ interneurons to TSC pathophysiology, offering insights for targeted therapeutic interventions.


Assuntos
Neurônios GABAérgicos , Interneurônios , Esclerose Tuberosa , Interneurônios/patologia , Interneurônios/metabolismo , Esclerose Tuberosa/patologia , Esclerose Tuberosa/metabolismo , Humanos , Neurônios GABAérgicos/patologia , Neurônios GABAérgicos/metabolismo , Masculino , Feminino , Eminência Mediana/patologia , Eminência Mediana/metabolismo , Somatostatina/metabolismo , Criança , Pré-Escolar , Receptores de GABA-A/metabolismo , Adolescente , Eminência Ganglionar
20.
Eur J Endocrinol ; 190(6): 458-466, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38771697

RESUMO

OBJECTIVE: The aim of this study is to compare the response to first-line medical treatment in treatment-naive acromegaly patients with pure growth hormone (GH)-secreting pituitary adenoma (GH-PA) and those with GH and prolactin cosecreting PA (GH&PRL-PA). DESIGN: This is a retrospective multicentric study of acromegaly patients followed from 2003 to 2023 in 33 tertiary Spanish hospitals with at least 6 months of first-line medical treatment. METHODS: Baseline characteristics, first-line medical treatment strategies, and outcomes were analyzed. We employed a multiple logistic regression full model to estimate the impact of some baseline characteristics on disease control after each treatment modality. RESULTS: Of the 144 patients included, 72.9% had a GH-PA, and 27.1% had a GH&PRL-PA. Patients with GH&PRL-PA were younger (43.9 ± 15.0 vs 51.9 ± 12.7 years, P < .01) and harboring more frequently macroadenomas (89.7% vs 72.1%, P = .03). First-generation somatostatin receptor ligand (fgSRL) as monotherapy was given to 106 (73.6%) and a combination treatment with fgSRL and cabergoline in the remaining 38 (26.4%). Patients with GH&PRL-PA received more frequently a combination therapy (56.4% vs 15.2%, P < .01). After 6 months of treatment, in the group of patients under fgSRL as monotherapy, those patients with GH&PRL-PA had worse control compared to GH-PAs (29.4% vs 55.1%, P = .04). However, these differences in the rate of disease control between both groups disappeared when both received combination treatment with fgSRL and cabergoline. CONCLUSION: In GH&PRL-PA, the biochemical control achieved with fgSRL as monotherapy is substantially worse than in patients harboring GH-PA, supporting the inclusion of cabergoline as first-line medical treatment in combination with fgSRLs in these subgroups of patients.


Assuntos
Acromegalia , Cabergolina , Prolactina , Humanos , Acromegalia/tratamento farmacológico , Acromegalia/sangue , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Cabergolina/uso terapêutico , Resultado do Tratamento , Prolactina/sangue , Adenoma Hipofisário Secretor de Hormônio do Crescimento/tratamento farmacológico , Adenoma Hipofisário Secretor de Hormônio do Crescimento/sangue , Adenoma Hipofisário Secretor de Hormônio do Crescimento/metabolismo , Hormônio do Crescimento Humano , Adenoma/tratamento farmacológico , Adenoma/sangue , Adenoma/metabolismo , Adenoma/complicações , Idoso , Quimioterapia Combinada , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/sangue , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/complicações , Espanha/epidemiologia
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