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1.
Artigo em Inglês | MEDLINE | ID: mdl-38568290

RESUMO

Selective serotonin reuptake inhibitors (SSRIs) are widely used drugs for the treatment of depression. Citalopram is one of the most prescribed SSRIs that is useful for the treatment of depression, obsessive-compulsive disorder, and anxiety disorders. On the other hand, crocin (active constitute of saffron) has pro-cognitive and mood enhancer effects. Also, both citalopram and crocin affect the function and expression of brain-derived neurotrophic factor (BDNF) and synaptophysin, two molecular factors that are involved in cognitive functions and mood. In the present study, we aim to investigate the interaction effect of citalopram and crocin on rats' performance in the open field test (locomotor activity and anxiety-like behavior) and the shuttle box (passive avoidance memory). Citalopram was injected at the doses of 10, 30, and 50 mg/kg, and crocin was injected at the dose of 50 mg/kg; all administrations were intraperitoneal. Real-time PCR was used to assess the expression level of BDNF and synaptophysin in the hippocampus. The results showed that citalopram (30 and 50 mg/kg) impaired passive avoidance memory and decreased BDNF and synaptophysin expression in the hippocampus, while crocin reversed memory impairment, and BDNF and synaptophysin expression in the hippocampus of rats received citalopram 30 mg/kg. Also, crocin partially showed these effects in rats that received citalopram 50 mg/kg. The results of the open field test were unchanged. In conclusion, we suggested that BDNF and synaptophysin may be involved in the effects of both citalopram and crocin.

2.
Acta Pharmacol Sin ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589687

RESUMO

Acute kidney injury (AKI) is often accompanied by uremic encephalopathy resulting from accumulation of uremic toxins in brain possibly due to impaired blood-brain barrier (BBB) function. Anionic uremic toxins are substrates or inhibitors of organic anionic transporters (OATs). In this study we investigated the CNS behaviors and expression/function of BBB OAT3 in AKI rats and mice, which received intraperitoneal injection of cisplatin 8 and 20 mg/kg, respectively. We showed that cisplatin treatment significantly inhibited the expressions of OAT3, synaptophysin and microtubule-associated protein 2 (MAP2), impaired locomotor and exploration activities, and increased accumulation of uremic toxins in the brain of AKI rats and mice. In vitro studies showed that uremic toxins neither alter OAT3 expression in human cerebral microvascular endothelial cells, nor synaptophysin and MAP2 expressions in human neuroblastoma (SH-SY5Y) cells. In contrast, tumour necrosis factor alpha (TNFα) and the conditioned medium (CM) from RAW264.7 cells treated with indoxyl sulfate (IS) significantly impaired OAT3 expression. TNFα and CM from IS-treated BV-2 cells also inhibited synaptophysin and MAP2 expressions in SH-SY5Y cells. The alterations caused by TNFα and CMs in vitro, and by AKI and TNFα in vivo were abolished by infliximab, a monoclonal antibody designed to intercept and neutralize TNFα, suggesting that AKI impaired the expressions of OAT3, synaptophysin and MAP2 in the brain via IS-induced TNFα release from macrophages or microglia (termed as IS-TNFα axis). Treatment of mice with TNFα (0.5 mg·kg-1·d-1, i.p. for 3 days) significantly increased p-p65 expression and reduced the expressions of Nrf2 and HO-1. Inhibiting NF-κB pathway, silencing p65, or activating Nrf2 and HO-1 obviously attenuated TNFα-induced downregulation of OAT3, synaptophysin and MAP2 expressions. Significantly increased p-p65 and decreased Nrf2 and HO-1 protein levels were also detected in brain of AKI mice and rats. We conclude that AKI inhibits the expressions of OAT3, synaptophysin and MAP2 due to IS-induced TNFα release from macrophages or microglia. TNFα impairs the expressions of OAT3, synaptophysin and MAP2 partly via activating NF-κB pathway and inhibiting Nrf2-HO-1 pathway.

3.
Indian J Otolaryngol Head Neck Surg ; 76(1): 1126-1129, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38440470

RESUMO

Neuroendocrine carcinoma originating from neuroendocrine cells is typically linked to unfavourable survival rates. We are introducing an exceptional case of neuroendocrine carcinoma occurring in the hypopharynx. To date, only a handful of instances involving primary neuroendocrine carcinoma of the hypopharynx have been documented. Advanced age, being male, a history of chronic alcoholism, smoking, and previous radiation are all risk factors associated with this condition. The majority of patients present with distant metastases and are not amenable to a complete cure. As there are no guidelines for the treatment of this rare tumour, various treatment modalities have been tried. Here, we are reporting one such case which was diagnosed as small-cell neuroendocrine carcinoma of the hypopharynx on the basis of histopathological cues and received concurrent chemoradiotherapy.

4.
Foods ; 13(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38397604

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disease that results in memory impairment. Aegle marmelos (L.) Correa (AM) is used as a traditional medicine. AM leaves have the potential to inhibit acetylcholinesterase activity. This study used scopolamine to induce AD in rats. The aim of this study was to investigate the effects of AM leaf extract using this model. Motor and memory functions were tested by the motor activity and Morris water maze (MWM) tests, respectively. The density of the synaptophysin and dendritic spines in the CA1 were detected by immunofluorescence and Golgi impregnation, respectively. The hippocampal histology was reviewed by H&E staining. After the treatment, the latency times in the MWM tests of the AD groups reduced, while the motor activities showed no difference. The density of the synaptophysin of the AD groups increased after the treatments, and that of the dendritic spines also increased in all AD groups post-treatment. The hippocampal tissue also recovered. AM leaf extract can improve cognitive impairment in AD models by maintaining the presynaptic vesicle proteins and dendritic spines in a dose-dependent manner.

5.
Diagn Pathol ; 19(1): 27, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326851

RESUMO

INTRODUCTION: NUT carcinoma is a rare cancer associated with a poor prognosis. Because of its rarity, its diagnosis is challenging and is usually made by excluding other diagnoses. Immunohistochemical analysis is a reliable technique that contributes to a correct diagnosis, but overestimating the expression of neuroendocrine (NE) markers may result in an incorrect diagnosis. In this study, we established the immunohistochemical phenotypes of NUT carcinoma compared with tumors that mimic its phenotype to identify potential diagnostic pitfalls. METHODS: Eight cases of NUT carcinoma were examined along with eight basaloid squamous cell carcinomas and thirteen cases of small cell carcinoma using an immunohistochemical panel consisting of various antibodies. RESULTS: Of the eight NUT carcinomas, three patients had a smoking history. All the cases examined for INSM1 were positive (6/6, 100%), although the staining was somewhat weak. Among the NE markers, synaptophysin was variably positive in two NUT carcinomas (2/6, 33%); however, all cases were negative for ASCL1, chromogranin A, and CD56. Moreover, the squamous cell markers, p40 and CK5/6, were weakly expressed in 4/6 (67%) and 3/6 (50%) of the NUT carcinomas, respectively. CONCLUSIONS: For tumors with an ambiguous morphology, applying the neuroendocrine phenotype of NUT carcinoma may be misleading; particularly, when distinguishing it from small-cell carcinoma. Similarly, null or weak expression of squamous cell markers may be observed in NUT carcinoma, but this differs from squamous cell carcinoma, which consistently demonstrates strong positivity for squamous cell markers.


Assuntos
Carcinoma Neuroendócrino , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Biomarcadores Tumorais/análise , Sinaptofisina/análise , Carcinoma de Células Escamosas/patologia , Neoplasias Pulmonares/patologia , Células Epiteliais/patologia , Fenótipo , Carcinoma Neuroendócrino/patologia , Proteínas Repressoras/análise
6.
Tissue Cell ; 87: 102313, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38286061

RESUMO

BACKGROUND: Doxorubicin (Dox) is one of the most effective anti-neoplastic agents. Quercetin (QE) exhibits antioxidant and anti-inflammatory properties. AIM: To detect neuroprotective properties of quercetin in rats exposed to doxorubicin-induced brain injury. MATERIAL AND METHODS: 48 rats were allocated equally into four groups: control group: (given normal saline), QE group: (given 80 mg/kg of QE orally daily for 2 weeks), Dox group: (received 2.5 mg/kg of Dox every other day for a total of seven intraperitoneal injections), and Dox+QE group: (received 2.5 mg/kg of Dox every other day for a total of seven intraperitoneal injections and 80 mg/kg of QE orally daily for 2 weeks). Subsequently, biochemical analyses were carried out along with histopathological (light and electron microscopic) and immunohistochemical examinations of the cerebral cortex and hippocampus. RESULTS: The Dox group revealed a decline in the activities of superoxide dismutase, catalase, and glutathione peroxidase, along with an increase in malondialdehyde and an increase in DNA damage. Furthermore, sections of the cerebral cortex and hippocampus revealed neurodegenerative changes, decreased synaptophysin, and increased Interleukin-1 beta expressions. Biochemical and histopathological results were markedly improved by QE administration. CONCLUSIONS: It can be concluded that QE induces protective effects against Dox-induced neurotoxicity.


Assuntos
Estresse Oxidativo , Quercetina , Ratos , Animais , Quercetina/farmacologia , Antioxidantes/farmacologia , Doxorrubicina/toxicidade , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Hipocampo , Dano ao DNA , Plasticidade Neuronal
7.
Acta Neuropathol Commun ; 12(1): 4, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38173031

RESUMO

Regional differences in synaptic degeneration may underlie differences in clinical presentation and neuropathological disease progression in Parkinson's Disease (PD) and Dementia with Lewy bodies (DLB). Here, we mapped and quantified synaptic degeneration in cortical brain regions in PD, PD with dementia (PDD) and DLB, and assessed whether regional differences in synaptic loss are linked to axonal degeneration and neuropathological burden. We included a total of 47 brain donors, 9 PD, 12 PDD, 6 DLB and 20 non-neurological controls. Synaptophysin+ and SV2A+ puncta were quantified in eight cortical regions using a high throughput microscopy approach. Neurofilament light chain (NfL) immunoreactivity, Lewy body (LB) density, phosphorylated-tau and amyloid-ß load were also quantified. Group differences in synaptic density, and associations with neuropathological markers and Clinical Dementia Rating (CDR) scores, were investigated using linear mixed models. We found significantly decreased synaptophysin and SV2A densities in the cortex of PD, PDD and DLB cases compared to controls. Specifically, synaptic density was decreased in cortical regions affected at Braak α-synuclein stage 5 in PD (middle temporal gyrus, anterior cingulate and insula), and was additionally decreased in cortical regions affected at Braak α-synuclein stage 4 in PDD and DLB compared to controls (entorhinal cortex, parahippocampal gyrus and fusiform gyrus). Synaptic loss associated with higher NfL immunoreactivity and LB density. Global synaptophysin loss associated with longer disease duration and higher CDR scores. Synaptic neurodegeneration occurred in temporal, cingulate and insular cortices in PD, as well as in parahippocampal regions in PDD and DLB. In addition, synaptic loss was linked to axonal damage and severe α-synuclein burden. These results, together with the association between synaptic loss and disease progression and cognitive impairment, indicate that regional synaptic loss may underlie clinical differences between PD and PDD/DLB. Our results might provide useful information for the interpretation of synaptic biomarkers in vivo.


Assuntos
Doença por Corpos de Lewy , Doenças do Sistema Nervoso , Doença de Parkinson , Humanos , Doença de Parkinson/patologia , alfa-Sinucleína , Doença por Corpos de Lewy/patologia , Corpos de Lewy/patologia , Sinaptofisina , Progressão da Doença
8.
Int J Surg Pathol ; : 10668969241226710, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291661
9.
Brain Res ; 1823: 148704, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38052316

RESUMO

Alzheimer's disease (AD) is a chronic, progressive neurodegenerative condition marked by cognitive impairment. Although coconut oil has been shown to be potentially beneficial in reducing AD-related cognitive deficits, information on its mechanism of action is limited. Thus, we investigated the effects of coconut oil on spatial cognitive ability and non-cognitive functions in a rat model of AD induced by G-galactose (D-GAL) and aluminum chloride (AlCl3), and examined the changes in synaptic transmission, cholinergic activity, neurotrophic factors and oxidative stress in this process. The AD model was established by administering D-GAL and AlCl3 for 90 days, while also supplementing with coconut oil during this time. Cognitive and non-cognitive abilities of the rats were evaluated at the end of the 90-day supplementation period. In addition, biochemical markers related to the pathogenesis of the AD were measures in the hippocampus tissue. Exposure to D-GAL/AlCl3 resulted in a reduction in locomotor activity, an elevation in anxiety-like behavior, and an impairment of spatial learning and memory (P < 0.05). The aforementioned behavioral disturbances were observed to coincide with increased oxidative stress and cholinergic impairment, as well as reduced synaptic transmission and levels of neurotrophins in the hippocampus (P < 0.05). Interestingly, treatment with coconut oil attenuated all the neuropathological changes mentioned above (P < 0.05). These findings suggest that coconut oil shows protective effects against cognitive and non-cognitive impairment, AD pathology markers, oxidative stress, synaptic transmission, and cholinergic function in a D-GAL/AlCl3-induced AD rat model.


Assuntos
Doença de Alzheimer , Transtornos Cognitivos , Disfunção Cognitiva , Fármacos Neuroprotetores , Ratos , Animais , Óleo de Coco/farmacologia , Cloreto de Alumínio/efeitos adversos , Transtornos Cognitivos/tratamento farmacológico , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/patologia , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Hipocampo , Estresse Oxidativo , Colinérgicos/farmacologia , Modelos Animais de Doenças , Galactose/toxicidade , Fármacos Neuroprotetores/uso terapêutico
10.
Pathologie (Heidelb) ; 45(1): 42-49, 2024 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-38091082

RESUMO

Neuroendocrine neoplasms (NENs) originate from various epithelial or neuroectodermal tissues, can occur in any organ, including the pancreas, and are characterized by the expression of the neuroendocrine markers synaptophysin and chromogranin A. Pancreatic neuroendocrine tumors (PanNETs) are well-differentiated epithelial neoplasms with morphological and immunohistochemical features of neuroendocrine differentiation of low, intermediate, or high grade. Pancreatic neuroendocrine carcinomas (PanNECs) are clinically aggressive, high-grade (poorly differentiated) carcinomas with morphologic features suggesting neuroendocrine differentiation, a high proliferative rate (> 20 mitoses per 2 mm2 and Ki67 index > 20%), and immunohistochemical labeling for neuroendocrine markers. They include the small cell neuroendocrine carcinoma and the large cell neuroendocrine carcinoma categories.Neuroendocrine-like morphology coupled with immunohistochemical markers of neuroendocrine differentiation are highly specific. However, neuroendocrine markers may also be expressed in non-neuroendocrine neoplasms, which can therefore be confused with NENs. Mimickers of pancreatic NENs comprise a number of important pitfall tumors, including epithelial and non-epithelial neoplasms, such as acinar cell carcinomas, solid pseudopapillary neoplasms (SPNs), or even non-neoplastic lesions. All of these lesions have the expression of neuroendocrine markers in common, such as synaptophysin and chromogranin A, and although they are comparatively rare, they can cause considerable diagnostic problems. This review article deals with some of the most important mimickers of pancreatic neuroendocrine neoplasms and even non-neoplastic lesions, such as islet aggregation. The similarities and differences between these entities and pancreatic neuroendocrine neoplasms are highlighted, and key findings that facilitate the correct diagnosis are discussed.


Assuntos
Carcinoma Neuroendócrino , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Humanos , Sinaptofisina , Cromogranina A , Tumores Neuroendócrinos/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Carcinoma Neuroendócrino/diagnóstico
11.
Ann Diagn Pathol ; 69: 152250, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38142627

RESUMO

Appendiceal neuroendocrine neoplasms (NENs) can present with various growth patterns including the traditional triad of histologic patterns-insular, trabecular and tubular. A small cluster pattern was also found in this study and the literature on this specific morphology is limited. In this study, we conducted a comprehensive review of appendiceal NENs from our institution over a ten-year period. Clinical and demographic data were obtained from medical records. Immunohistochemical stains were performed with antibodies specific for synaptophysin, chromogranin, INSM1, CD56, serotonin and peptide YY. The small cluster pattern was found in 29.4 % of all cases evaluated. The tumor cells in these cases were predominantly located at the distal tip of the appendix, associated with fibrous obliteration. These tumors were smaller in size and tended towards less advanced tumor stage, with reduced incidence of lymphovascular and/or perineural invasion. Chromogranin expression was identified in 76 % of these cases. There is a heterogeneous hormone profile with 46.7 % serotonin and 33.3 % peptide YY. In conclusion, the small cluster pattern NENs present with unique histological features and hormone expression profile. Among the various neuroendocrine markers, INSM1 showed superior diagnostic performance, with high sensitivity and minimal non-specific staining.


Assuntos
Neoplasias do Apêndice , Carcinoma Neuroendócrino , Neoplasias Intestinais , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Neoplasias Gástricas , Humanos , Tumores Neuroendócrinos/patologia , Biomarcadores Tumorais/metabolismo , Cromograninas , Peptídeo YY , Serotonina , Proteínas Repressoras/metabolismo , Sensibilidade e Especificidade , Sinaptofisina/metabolismo , Neoplasias do Apêndice/diagnóstico , Carcinoma Neuroendócrino/patologia
12.
Australas J Dermatol ; 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38095137

RESUMO

We report a case of a 55-year-old female with an asymptomatic pink-brown nodule. Histological examination demonstrated a composite haemangioendothelioma with positive synaptophysin staining.

13.
Front Endocrinol (Lausanne) ; 14: 1205631, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38125789

RESUMO

Background: The significance of neuroendocrine (NE) markers in triple-negative breast cancer (TNBC) patients has not been investigated. This study aims to clarify the incidence and prognostic significance of NE marker expression in TNBC, determine its association with other clinicopathological parameters, and further explore the pathological features and potential treatment options for TNBC patients expressing NE markers. Methods: Clinicopathological data were collected from 396 TNBC patients undergoing radical breast cancer surgery at Peking Union Medical College Hospital from January 2002 to December 2014, with a final follow-up in July 2019. Immunohistochemistry (IHC) staining was performed for NE markers including chromogranin A (CgA) and synaptophysin (Syn). For TNBC patients with positive NE marker expression, IHC staining was then performed for alpha-thalassemia/mental retardation X-linked (ATRX), O(6)-methylguanine-methyltransferase (MGMT), somatostatin receptor 2 (SSTR2), and programmed death receptor-ligand 1 (PD-L1). The chi-square or Fisher exact test was used to evaluate the correlations between NE marker expression and other parameters. Survival curves were plotted using the Kaplan-Meier (K-M) method to assess the prognostic significance of NE markers in TNBC. Results: NE marker-positive staining was observed in 7.6% (30/396) of all TNBC cases. Only 0.5% (2/396) cases had ≥ 90% neoplastic cells expressing NE markers. Positive NE marker expression was associated with negative basal-like marker expression. K-M survival analysis showed that the NE marker-positive TNBC patients had higher disease-free survival (DFS) rates than the NE marker-negative patients at the same stage. Among the 30 NE marker-positive TNBC cases, 13.3% and 26.7% showed negative IHC staining for ATRX and MGMT, respectively, while 13.3% had a 3+ score for SSTR2 IHC staining. For PD-L1 IHC staining, 13.3% of the 30 TNBC cases were higher than 10 scores in Combined Positive Score (CPS), and 10.0% were higher than 10% in Tumor Cell Proportion Score (TPS). Conclusion: There was a small proportion of TNBC patients expressing NE markers. TNBC patients with positive NE marker expression had a better prognosis than the negative group at the same stage. TNBC cases with positive NE marker expression may potentially benefit from immunotherapy or somatostatin analogue treatment.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/metabolismo , Antígeno B7-H1/metabolismo , Prognóstico , Intervalo Livre de Doença , Mastectomia
14.
Mol Neurobiol ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38010560

RESUMO

Memory problems are often the first signs of cognitive impairment related to Alzheimer's disease (AD), and stem cells and stem cell-derived exosomes (EXOs) have been studied for their therapeutic potential to improve the disease signs. While many studies have shown the anti-inflammatory and immunomodulatory effects of stem cells and exosomes on improving memory in different AD models, there is still insufficient data to determine how they modulate neural plasticity to enhance spatial memory and learning ability. Therefore, we conducted a study to investigate the effects of exosomes derived from 3D-cultured human Unrestricted Somatic Stem Cells (hUSSCs) on spatial memory and neuroplasticity markers in a sporadic rat model of AD. Using male Wistar rats induced by intracerebral ventricle injection of streptozotocin, we demonstrated that intranasal administration of hUSSC-derived exosomes could decrease Aß accumulation and improve learning and memory in the Morris water maze test. We also observed an increase in the expression of pre-synaptic and post-synaptic molecules involved in neuronal plasticity, including NMDAR1, integrin ß1, synaptophysin, pPKCα, and GAP-43, in the hippocampus. Our findings suggest that intranasal administration of exosomes can ameliorate spatial learning and memory deficits in rats, at least in part, by increasing the expression of neuroplasticity proteins. These results may encourage researchers to further investigate the molecular pathways involved in memory improvement after stem cell and exosome therapy, with the goal of increasing the efficacy and safety of exosome-based treatments for AD.

15.
Neurobiol Stress ; 27: 100580, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37920548

RESUMO

Maternal infection during pregnancy and childhood social trauma have been associated with neurodevelopmental and affective disorders, such as schizophrenia, autism spectrum disorders, bipolar disorder and depression. These disorders are characterized by changes in microglial cells, which play a notable role in synaptic pruning, and synaptic deficits. Here, we investigated the effect of prenatal infection and social adversity during adolescence - either alone or in combination - on behavior, microglia, and synaptic density. Male offspring of pregnant rats injected with poly I:C, mimicking prenatal infection, were exposed to repeated social defeat during adolescence. We found that maternal infection during pregnancy prevented the reduction in social behavior and increase in anxiety induced by social adversity during adolescence. Furthermore, maternal infection and social adversity, alone or in combination, induced hyperlocomotion in adulthood. Longitudinal in vivo imaging with [11C]PBR28 positron emission tomography revealed that prenatal infection alone and social adversity during adolescence alone induced a transient increase in translocator protein TSPO density, an indicator of glial reactivity, whereas their combination induced a long-lasting increase that remained until adulthood. Furthermore, only the combination of prenatal infection and social adversity during adolescence induced an increase in microglial cell density in the frontal cortex. Prenatal infection increased proinflammatory cytokine IL-1ß protein levels in hippocampus and social adversity reduced anti-inflammatory cytokine IL-10 protein levels in hippocampus during adulthood. This reduction in IL-10 was prevented if rats were previously exposed to prenatal infection. Adult offspring exposed to prenatal infection or adolescent social adversity had a higher synaptic density in the frontal cortex, but not hippocampus, as evaluated by synaptophysin density. Interestingly, such an increase in synaptic density was not observed in rats exposed to the combination of prenatal infection and social adversity, perhaps due to the long-lasting increase in microglial density, which may lead to an increase in microglial synaptic pruning. These findings suggest that changes in microglia activity and cytokine release induced by prenatal infection and social adversity during adolescence may be related to a reduced synaptic pruning, resulting in a higher synaptic density and behavioral changes in adulthood.

16.
Front Cell Neurosci ; 17: 1277729, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37927445

RESUMO

In presynaptic terminals 4 types of endocytosis, kiss-and-run, clathrin-mediated, bulk and ultrafast endocytosis have been reported to maintain repetitive exocytosis of neurotransmitter. However, detailed characteristics and relative contribution of each type of endocytosis still need to be determined. Our previous live-cell imaging study demonstrated individual exocytosis events of synaptic vesicle within an active-zone-like membrane (AZLM) formed on glass using synaptophysin tagged with a pH-sensitive fluorescent protein. On the other hand, individual endocytosis events of postsynaptic receptors were recorded with a rapid extracellular pH exchange method. Combining these methods, here we live-cell imaged endocytosed synaptophysin with total internal reflection fluorescence microscopy in rat hippocampal culture preparations. Clathrin-dependent and -independent endocytosis, which was seemingly bulk endocytosis, occurred within several seconds after electrical stimulation at multiple locations around AZLM at room temperature, with the locations varying trial to trial. The contribution of clathrin-independent endocytosis was more prominent when the number of stimulation pulses was large. The skewness of synaptophysin distribution in intracellular vesicles became smaller after addition of a clathrin inhibitor, which suggests that clathrin-dependent endocytosis concentrates synaptophysin. Ultrafast endocytosis was evident immediately after stimulation only at near physiological temperature and was the predominant endocytosis when the number of stimulation pulses was small.

17.
Proc Natl Acad Sci U S A ; 120(45): e2311484120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37903271

RESUMO

The synaptic vesicle protein Synaptophysin (Syp) has long been known to form a complex with the Vesicle associated soluble N-ethylmaleimide sensitive fusion protein attachment receptor (v-SNARE) Vesicle associated membrane protein (VAMP), but a more specific molecular function or mechanism of action in exocytosis has been lacking because gene knockouts have minimal effects. Utilizing fully defined reconstitution and single-molecule measurements, we now report that Syp functions as a chaperone that determines the number of SNAREpins assembling between a ready-release vesicle and its target membrane bilayer. Specifically, Syp directs the assembly of 12 ± 1 SNAREpins under each docked vesicle, even in the face of an excess of SNARE proteins. The SNAREpins assemble in successive waves of 6 ± 1 and 5 ± 2 SNAREpins, respectively, tightly linked to oligomerization of and binding to the vesicle Ca++ sensor Synaptotagmin. Templating of 12 SNAREpins by Syp is likely the direct result of its hexamer structure and its binding of VAMP2 dimers, both of which we demonstrate in detergent extracts and lipid bilayers.


Assuntos
Fusão de Membrana , Vesículas Sinápticas , Sinaptofisina/genética , Sinaptofisina/metabolismo , Fusão de Membrana/fisiologia , Vesículas Sinápticas/metabolismo , Sinaptotagminas/metabolismo , Proteínas SNARE/metabolismo , Exocitose/fisiologia
18.
Curr Med Sci ; 43(5): 988-997, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37755634

RESUMO

OBJECTIVE: Previous research indicates a link between cognitive impairment and chronic kidney disease (CKD), but the underlying factors are not fully understood. This study aimed to investigate the progression of CKD-induced cognitive impairment and the involvement of cognition-related proteins by developing early- and late-stage CKD models in Sprague-Dawley rats. METHODS: The Morris water maze test and the step-down passive avoidance task were performed to evaluate the cognitive abilities of the rats at 24 weeks after surgery. Histopathologic examinations were conducted to examine renal and hippocampal damage. Real-time PCR, Western blotting analysis, and immunohistochemical staining were carried out to determine the hippocampal expression of brain-derived neurotrophic factor (BDNF), choline acetyltransferase (ChAT), and synaptophysin (SYP). RESULTS: Compared with the control rats, the rats with early-stage CKD exhibited mild renal damage, while those with late-stage CKD showed significantly increased serum creatinine levels as well as apparent renal and brain damage. The rats with early-stage CKD also demonstrated significantly impaired learning abilities and memory compared with the control rats, with further deterioration observed in the rats with late-stage CKD. Additionally, we observed a significant downregulation of cognition-related proteins in the hippocampus of rats with early-stage CKD, which was further exacerbated with declining renal function as well as worsening brain and renal damage in rats with late-stage CKD. CONCLUSION: These results suggest the importance of early screening to identify CKD-induced cognitive dysfunction promptly. In addition, the downregulation of cognition-related proteins may play a role in the progression of cognitive dysfunction.

19.
J Pathol Clin Res ; 9(6): 498-509, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37608427

RESUMO

Complementary to synaptophysin and chromogranin A, insulinoma-associated protein 1 (INSM1) has emerged as a sensitive marker for the diagnosis of neuroendocrine neoplasms. Since there are no comparative data regarding INSM1 expression in conventional colorectal adenocarcinomas (CRCs) and colorectal mixed adenoneuroendocrine carcinomas/neuroendocrine carcinomas (MANECs/NECs), we examined INSM1 in a large cohort of conventional CRCs and MANECs/NECs. In conventional CRC, we put a special focus on conventional CRC with diffuse expression of synaptophysin, which carry the risk of being misinterpreted as a MANEC or a NEC. We investigated INSM1 according to the immunoreactive score in our main cohort of 1,033 conventional CRCs and 21 MANECs/NECs in comparison to the expression of synaptophysin and chromogranin A and correlated the results with clinicopathological parameters and patient survival. All MANECs/NECs expressed INSM1, usually showing high or moderate expression (57% high, 34% moderate, and 9% low), which distinguished them from conventional CRCs, which were usually INSM1 negative or low, even if they diffusely expressed synaptophysin. High expression of INSM1 was not observed in conventional CRCs. Chromogranin A was negative/low in most conventional CRCs (99%), but also in most MANECs/NECs (66%). Comparable results were observed in our independent validation cohorts of conventional CRC (n = 274) and MANEC/NEC (n = 19). Similar to synaptophysin, INSM1 expression had no prognostic relevance in conventional CRCs, while true MANEC/NEC showed a highly impaired survival in univariate and multivariate analyses (e.g. disease-specific survival: p < 0.001). MANECs/NECs are a highly aggressive variant of colorectal cancer, which must be reliably identified. High expression of INSM1 distinguishes MANEC/NEC from conventional CRCs with diffuse expression of the standard neuroendocrine marker synaptophysin, which do not share the same dismal prognosis. Therefore, high INSM1 expression is a highly specific/sensitive marker that is supportive for the diagnosis of true colorectal MANEC/NEC.

20.
Ann Diagn Pathol ; 67: 152181, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37598464

RESUMO

Primary diagnosis of bronchial carcinoids (BC) is always made on biopsies and additional immunohistochemistry (IHC) is often necessary. In the present study we investigated the concordance of common diagnostic (synaptophysin, chromogranin, CD56 and INSM-1) and potential prognostic (OTP, CD44, Rb and p16) IHC markers between the preoperative biopsies and resections of in total 64 BCs, 26 typical (41 %) and 38 atypical (59 %) carcinoid tumors. Synaptophysin and chromogranin had 100 % concordance in all resected carcinoids and paired diagnostic biopsies. Synaptophysin was not affected by variable expression in biopsies compared to chromogranin, CD56 and INSM-1. Notably, INSM-1 IHC was false negative in 8 % of biopsies. Of the novel and potential prognostic markers, only CD44 showed 100 % concordance between biopsies and resections, while OTP showed two (4 %) false negative results in paired biopsies. While Rb IHC was false negative in 8 % of biopsies, no strong and diffuse pattern of p16 expression was observed. In this study, most false negative IHC results (85 %, 22/26) were observed in small flexible biopsies. Taken together, our data suggest excellent concordance of synaptophysin and CD44 on the preoperative biopsy samples, while other neuroendocrine markers, Rb and OTP should be interpreted with caution, especially in small biopsies.


Assuntos
Tumor Carcinoide , Neoplasias Pulmonares , Humanos , Sinaptofisina/metabolismo , Cromograninas , Biomarcadores Tumorais/metabolismo , Imuno-Histoquímica , Tumor Carcinoide/diagnóstico , Tumor Carcinoide/cirurgia , Biópsia , Neoplasias Pulmonares/patologia
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