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ATP is a pleiotropic cell‐to‐cell signaling molecule in the brain that functions through activation of the P2 receptors (P2R), encompassing ionotropic P2XR or metabotropic P2YR. Noxious brain insults increase the extracellular levels of ATP and previous studies have implicated different P2R, namely P2Y1R, in the control of ischemic brain damage, but it remains to be defined if P2Y1R antagonists also alleviate the behavioral impairments associated with brain ischemia. Furthermore, as P2Y1R can control neuronal and glial functions, we explored if P2Y1R antagonist‐mediated protection would mainly involve neuronal and/or glial processes. Adult male mice subject to permanent middle cerebral artery occlusion (pMCAO) displayed an infarcted cortical area (2,3,5‐triphenyltetrazolium chloride staining), decreased neurological score with decreased working and reference memory performance (Y‐maze, object recognition and aversive memory), accompanied by neuronal damage (FluoroJade C), astrogliosis (glial fibrillary acidic protein) and microgliosis (CD11b). All of these changes were attenuated by intracerebroventricular pre‐treatment (10 min before pMCAO) with the generic P2R antagonist 4‐[(E)‐{4‐formyl‐5‐hydroxy‐6‐methyl‐3‐[(phosphono‐oxy)methyl]pyridin‐2‐yl}diazenyl]benzene‐1,3‐disulfonic acid (PPADS, 0.5–1.0 nmol/μL). In contrast, the selective P2Y1R antagonist (1R*,2S*)‐4‐[2‐Iodo‐6‐(methylamino)‐9H‐purin‐9‐yl]‐2‐(phosphono‐oxy)bicycle[3.1.0] hexane‐1‐methanol dihydrogen phosphate ester (MRS2500, 1.0–2.0 nmol/μL) afforded equivalent behavioral benefits but only prevented neuronal damage but not astrogliosis or microgliosis upon pMCAO. These results indicated that P2Y1R‐associated neuroprotection mainly occurred through neuronal mechanisms, whereas other P2R were also involved in the control of astrocytic reactivity upon brain injury.  相似文献   
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BackgroundAnimal models are widely used in scientific research in order to obtain information from a whole organism under a specific set of experimental conditions. Various lineages of mice have been used to investigate diseases and new therapeutic strategies, and, consequently, hematological and biochemical tests in these laboratory animals are essential to validate scientific studies. Our study seeks to establish reference values for hematological and biochemical parameters of four lineages of mice.MethodsWe evaluated the hematological and biochemical profiles of 20 males and 20 females from the lineages Swiss (heterogeneous), BALB/c and C57BL/6 (isogenic), and B6D2F1 (hybrid), totaling 160 mice. Analysis were standardized using the systems pocH‐100iV Diff™ for 19 hematological parameters and VITROS® 350 for 12 biochemical parameters.ResultsResults are shown as means and standard deviation, grouped by lineage and genre. Comparing the values obtained in this study with the values from previous studies, some variations were detected, which could be explained by differences in methodologies or individual variability.ConclusionThus our study shows that knowledge and disclosure of the values of physiological parameters of laboratory animals is necessary, and emphasises the importance of considering variations influenced by gender, lineage and genotype in the choice of the best experimental model.  相似文献   
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Type I diabetes mellitus (T1DM) is an autoimmune disorder featured by raised glucoses levels. It has been hypothesised that raised glucose levels in T1DM might be recognised as PAMPs, leading to immune response by overloading the cell receptors for pathogens recognition. DC-SIGN is a transmembrane protein, present in dendritic cells (DC) and macrophages: it has an important role in inflammatory response and T cells activation. Notably, DC-SIGN activation and triggering of the immune response depend on the type of ligand, which may lead to a pro or anti-inflammatory pathway. In our association study, we analysed the SNPs rs4804803 (−336 A>G) and rs735239 (−871 A>G), both at DC-SIGN promoter region, in 210 T1DM patients and 157 healthy controls, also looking for a correlation with the age of onset of the disease. We found that the allele G and genotypes G/G and A/G of SNP-871 (rs735239), as well as the alleles G-G (rs735239-rs4804803) and genotypes combined AA-GG (rs735239-rs4804803) were associated with protection of T1DM development. We did not find association between these variations with the age of onset of the disease and the presence of other autoimmune disorders. Our results suggest that SNPs in DC-SIGN promoter region can be associated to protection for T1DM in the Northeast Brazilian population.  相似文献   
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The effects of various means of interfering with androgen action on rat coagulating gland, ventral prostate, lateral type 1 prostate, lateral type 2 prostate, and dorsal prostate were examined morphologically and quantitatively by assessing DNA content, wet weight, protein content, and zinc concentrations. Adult male Sprague-Dawley rats were subjected to 2 weeks of interfering with androgen action by treatment with Leuprolelin (a luteinizing hormone-releasing hormone analog), Finasteride (a 5α-reductase inhibitor), or diethylstilbestrol (DES), or by physical castration. For all prostatic lobes, inhibition of 5α-reductase elicited the smallest reduction in prostatic wet weight, DNA and protein contents, and zinc concentration. The most profound reductions in all parameters were elicited by castration. Treatments with DES and Leuprolelin gave intermediate effects with DES being the more effective in reducing all parameters in all prostatic lobes. Morphological changes elicited by all forms of androgen blockade were reduction of epithelial height, relative increase of connective tissue, reduction in ductal diameter, length, and number. The order of effectiveness of the various treatments on morphological features was as described above. While all forms of androgen blockade elicited similar effects throughout the prostate, differences in response to all forms of interference with androgen action were observed in different lobes of the prostate with regard to wet weight, DNA and protein contents, and zinc concentration as well as morphological effects. Regressive changes at the morphological level were particularly striking in the coagulating gland and ventral prostate, and indistinct in the lateral type 2 prostate. Prostatic zinc concentration in both normal and androgen-deprived rats was the highest in the lateral type 2 prostate and was reduced by interfering with androgen action to the greatest extent in the dorsolateral prostate (lateral type 1 and type 2, and dorsal prostate). The distribution of zinc correlated with the expression of metallothionein, which was detected by immunocytochemistry only in the lateral type 2 prostate of both normal and androgen-deprived rats. Intraprostatic heterogeneity of zinc and metallothionein expression emphasizes interlobar differences in biological function within the rat prostate. The mechanism of development of regional heterogeneity within the prostate may shed light on the pathogenesis of prostatic proliferative diseases (prostatic hyperplasia and prostatic cancer) that initially owe their development to focal changes within large cell populations. © 1996 Wiley-Liss, Inc.  相似文献   
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Background: This narrative review presents the association between metabolic syndrome (MetS), along with its components, and cognition-related disorders, as well as the potential reversal role of diet against cognitive impairment by modulating MetS. Methods: An electronic research in Medline (Pubmed) and Scopus was conducted. Results: MetS and cognitive decline share common cardiometabolic pathways as MetS components can trigger cognitive impairment. On the other side, the risk factors for both MetS and cognitive impairment can be reduced by optimizing the nutritional intake. Clinical manifestations such as dyslipidemia, hypertension, diabetes and increased central body adiposity are nutrition-related risk factors present during the prodromal period before cognitive impairment. The Mediterranean dietary pattern stands among the most discussed predominantly plant-based diets in relation to cardiometabolic disorders that may prevent dementia, Alzheimer’s disease and other cognition-related disorders. In addition, accumulating evidence suggests that the consumption of specific dietary food groups as a part of the overall diet can improve cognitive outcomes, maybe due to their involvement in cardiometabolic paths. Conclusions: Early MetS detection may be helpful to prevent or delay cognitive decline. Moreover, this review highlights the importance of healthy nutritional habits to reverse such conditions and the urgency of early lifestyle interventions.  相似文献   
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