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排序方式: 共有4477条查询结果,搜索用时 15 毫秒
81.
Claudia Emanuele Carvalho-Sousa Eliana P. Pereira Gabriela S. Kinker Mariana Veras Zulma S. Ferreira Fernanda P. Barbosa-Nunes Joilson O. Martins Paulo H.N. Saldiva Russel J. Reiter Pedro A. Fernandes Sanseray da Silveira Cruz-Machado Regina P. Markus 《Journal of pineal research》2020,68(3):e12636
Environmental pollution in the form of particulate matter <2.5 μm (PM2.5) is a major risk factor for diseases such as lung cancer, chronic respiratory infections, and major cardiovascular diseases. Our goal was to show that PM2.5 eliciting a proinflammatory response activates the immune-pineal axis, reducing the pineal synthesis and increasing the extrapineal synthesis of melatonin. Herein, we report that the exposure of rats to polluted air for 6 hours reduced nocturnal plasma melatonin levels and increased lung melatonin levels. Melatonin synthesis in the lung reduced lipid peroxidation and increased PM2.5 engulfment and cell viability by activating high-affinity melatonin receptors. Diesel exhaust particles (DEPs) promoted the synthesis of melatonin in a cultured cell line (RAW 264.7 cells) and rat alveolar macrophages via the expression of the gene encoding for AANAT through a mechanism dependent on activation of the NFκB pathway. Expression of the genes encoding AANAT, MT1, and MT2 was negatively correlated with cellular necroptosis, as disclosed by analysis of Gene Expression Omnibus (GEO) microarray data from the human alveolar macrophages of nonsmoking subjects. The enrichment score for antioxidant genes obtained from lung gene expression data (GTEx) was significantly correlated with the levels of AANAT and MT1 but not the MT2 melatonin receptor. Collectively, these data provide a systemic and mechanistic rationale for coordination of the pineal and extrapineal synthesis of melatonin by a standard damage-associated stimulus, which activates the immune-pineal axis and provides a new framework for understanding the effects of air pollution on lung diseases. 相似文献
82.
Jan Detka Joanna Ślusarczyk Anna Kurek Mateusz Kucharczyk Tomasz Adamus Paweł Konieczny Marta Kubera Agnieszka Basta-Kaim Władysław Lasoń Bogusława Budziszewska 《Pharmacological reports : PR》2019,71(2):338-346
Background
In depression, excessive glucocorticoid action may cause maladaptive brain changes, including in the pathways controlling energy metabolism. Insulin and glucagon-like peptide-1 (GLP-1), besides regulation of glucose homeostasis, also possess neurotrophic properties. Current study was aimed at investigating the influence of prenatal stress (PS) on insulin, GLP-1 and their receptor (IR and GLP-1R) levels in the hypothalamus. GLP-1 and GLP-1R were assayed also in the hippocampus and frontal cortex – brain regions mainly affected in depression. The second objective was to determine the influence of exendin-4 and insulin on CRH promoter gene activity in in vitro conditions.Methods
Adult male PS rats were subjected to acute stress and/or received orally glucose. Levels of hormones and their receptors were assayed with ELISA method. In vitro studies were performed on mHypoA-2/12?hypothalamic cell line, stably transfected with CRH promoter coupled with luciferase.Results
PS has reduced GLP-1 and GLP-1R levels, attenuated glucose-induced increase in insulin concentration and increased the amount of phosphorylated IR in the hypothalamus of animals subjected to additional stress stimuli, and also decreased the GLP-1R level in the hippocampus. In vitro studies demonstrated that insulin is capable of increasing CRH promoter activity in the condition of stimulation of the cAMP/PKA pathway in the applied cellular model.Conclusion
Prenatal stress may act as a preconditioning factor, affecting the concentrations of hormones such as insulin and GLP-1 in the hypothalamus in response to adverse stimuli. The decreased GLP-1R level in the hippocampus could be linked with the disturbances in neuronal plasticity. 相似文献83.
B cells are recognized as the main effector cells of humoral immunity which suppress tumor progression by secreting immunoglobulins, promoting T cell response, and killing cancer cells directly. Given these properties, their anti-tumor immune response in the tumor micro-environment (TME) is of great interest. Although T cell-related immune responses have become a therapeutic target with the introduction of immune checkpoint inhibitors, not all patients benefit from these treatments. B cell and B cell-related pathways (CCL19, −21/CCR7 axis and CXCL13/CXCR5 axis) play key roles in activating immune response through humoral immunity and local immune activation via tertiary lymphoid structure (TLS) formation. However they have some protumorigenic works in the TME. Thus, a better understanding of B cell and B cell-related pathways is necessary to develop effective cancer control. In this review, we summarize recent evidences regarding the roles of B cell and B cell-related pathways in the TME and immune response and discuss their potential roles for novel cancer treatment strategies. 相似文献
84.
Caroline G. M. de Theije Bas M. Bavelaar Sofia Lopes da Silva Sijmen Mechiel Korte Berend Olivier Johan Garssen Aletta D. Kraneveld 《Pediatric allergy and immunology》2014,25(3):218-226
Autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) are neurodevelopmental disorders which occur in childhood and may persist into adulthood. Although the etiology of these disorders is largely unknown, genetic and environmental factors are thought to play a role in the development of ASD and ADHD. Allergic immune reactions, in prenatal and postnatal phases, are examples of these environmental factors, and adverse reactions to foods are reported in these children. In this review, we address the clinical and preclinical findings of (food) allergy in ASD and ADHD and suggest possible underlying mechanisms. Furthermore, opportunities for nutritional interventions in neurodevelopmental disorders are provided. 相似文献
85.
Functional gastrointestinal disorders (FGIDs) are highly prevalent and pose a significant burden on health care and society, and impact patients’ quality of life. FGIDs comprise a heterogeneous group of disorders, with unclear underlying pathophysiology. They are considered to result from the interaction of altered gut physiology and psychological factors via the gut-brain axis, where brain and gut symptoms are reciprocally influencing each other’s expression. Intestinal microbiota, as a part of the gut-brain axis, plays a central role in FGIDs. Patients with Irritable Bowel Syndrome, a prototype of FGIDs, display altered composition of the gut microbiota compared with healthy controls and benefit, at the gastrointestinal and psychological levels, from the use of probiotics and antibiotics. This review aims to recapitulate the available literature on FGIDs and microbiota-gut-brain axis. 相似文献
86.
87.
《Scandinavian journal of gastroenterology》2013,48(9):892-896
Background: After nutrient ingestion there is an early response of glucagon-like peptide 1 (GLP-1) immunoreactivity, although GLP-1 is mainly produced in endocrine cells from the lower gut (ileum and colon/rectum), suggesting that indirect stimulation is important after the ingestion of carbohydrates that are predominantly absorbed from the upper intestine.Methods: To enable contact of sucrose with lower gut mucosa, sucrose was administered by mouth with and without the simultaneous ingestion of 100mg of the α-glucosidase inhibitor acarbose to six normal healthy volunteers.Results: There was an early increment in GLP-1 15min after sucrose ingestion. With acarbose, sucrose reached the colon approximately 120min after ingestion, as indicated by an increment in breath hydrogen exhalation (p < 0.0001), and GLP-1 release was prolonged (p < 0.0001). The sucrose-related increments in glucose, insulin, C-peptide, and gastric inhibitory polypeptide (GIP) and the suppression of glucagon were only marginally affected by acarbose administration.Conclusions: GLP-1 release appears to be influenced by indirect mechanisms (early response after sucrose) and by direct luminal contact with lower gut mucosal endocrine cells (late response with acarbose). 相似文献
88.
Emotional stress has been recognized as a modifiable risk factor for cardiovascular diseases. Adolescence has been proposed as a developmental period of vulnerability to stress. This idea has been mainly supported by experimental research in animals demonstrating a higher impact of chronic emotional stress in adolescents compared with adults. Adolescent vulnerability is also based on evidence that stress during this developmental period affects development, so that enduring changes are found in adult animals that experienced stress during adolescence. The purpose of the present review is to discuss experimental research in rodent models that investigated the impact of long-term exposure to stressful events during adolescence on cardiovascular function. The development of cardiovascular function and autonomic activity in rodents is initially reviewed. Then, a discussion of an adolescent vulnerability to cardiovascular effects of chronic stress is presented. From the reviewed literature, perspective for future research is proposed to better elucidate adolescent vulnerability to cardiovascular complications evoked by chronic emotional stress. 相似文献
89.
90.
Michael Saina Grigory Genikhovich Eduard Renfer Ulrich Technau 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(44):18592-18597
The TGF-β molecules Dpp/BMP2/4/7 and their antagonist Sog/Chd play a conserved role in establishing the dorso-ventral (DV) axis in bilaterians. Homologues of BMPs and the antagonist, Chordin, have been isolated from Cnidaria and show a striking asymmetric expression pattern with respect to the primary oral-aboral (OA) axis. We used Morpholino knockdowns of Nematostella dpp (bmp2/4), bmp5-8, chordin, and tolloid to investigate their function during early development of the sea anemone Nematostella vectensis. Molecular analysis of the BMP Morpholino phenotypes revealed an upregulated and radialized expression of bmps and chordin in ectoderm and endoderm indicating a negative feedback loop. Our data further suggest that BMP signaling is required for symmetry breaking of bmp and chordin expression during gastrulation. While bmps and chordin marker genes of the ectodermal OA axis extended aborally, other ectodermal markers of the OA axis were not significantly affected. By contrast, expression of other endodermal marker genes marking both the OA and the directive axis were abolished. Our data suggest that the logic of BMP2/4 signaling and the BMP antagonist, Chordin, differs significantly between Cnidaria and Bilateria, yet the double negative feedback loop detected in Nematostella bears systemic similarities with part of the regulatory network of the DV axis patterning system in amphibians. 相似文献