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1.
Croat Med J ; 65(2): 122-137, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38706238

RESUMO

AIM: To compare the effectiveness of artificial neural network (ANN) and traditional statistical analysis on identical data sets within the splenectomy-middle carotid artery occlusion (MCAO) mouse model. METHODS: Mice were divided into the splenectomized (SPLX) and sham-operated (SPLX-sham) group. A splenectomy was conducted 14 days before middle carotid artery occlusion (MCAO). Magnetic resonance imaging (MRI), bioluminescent imaging, neurological scoring (NS), and histological analysis, were conducted at two, four, seven, and 28 days after MCAO. Frequentist statistical analyses and ANN analysis employing a multi-layer perceptron architecture were performed to assess the probability of discriminating between SPLX and SPLX-sham mice. RESULTS: Repeated measures ANOVA showed no significant differences in body weight (F (5, 45)=0.696, P=0.629), NS (F (2.024, 18.218)=1.032, P=0.377) and brain infarct size on MRI between the SPLX and SPLX-sham groups post-MCAO (F (2, 24)=0.267, P=0.768). ANN analysis was employed to predict SPLX and SPL-sham classes. The highest accuracy in predicting SPLX class was observed when the model was trained on a data set containing all variables (0.7736±0.0234). For SPL-sham class, the highest accuracy was achieved when it was trained on a data set excluding the variable combination MR contralateral/animal mass/NS (0.9284±0.0366). CONCLUSION: This study validated the neuroprotective impact of splenectomy in an MCAO model using ANN for data analysis with a reduced animal sample size, demonstrating the potential for leveraging advanced statistical methods to minimize sample sizes in experimental biomedical research.


Assuntos
Modelos Animais de Doenças , Infarto da Artéria Cerebral Média , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Esplenectomia , Animais , Camundongos , Esplenectomia/métodos , Infarto da Artéria Cerebral Média/cirurgia , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Tamanho da Amostra , Masculino
2.
J Perinat Med ; 51(1): 39-50, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36087294

RESUMO

It is very complicated to give correct answer to the question "How to define human life?" Nowadays dilemmas consider the respect of human life from the birth to death involve not just biology but also other sciences like philosophy, theology, sociology, psychology, law and politics. These sciences evaluate the topic from different points of view. Integration of all of these perspectives could result with a proper definition. The principal purpose of this paper is to try to determine when a human individual begins. If this proves to be too difficult, we might have to settle for a specific stage in the reproductive process before which it would be impossible to say with any plausibility that a human individual exists. It is necessary to return the moral dimension of observation to the science of life. The point is to reconcile the universal ethical principles concerning the absolute value of life with the everyday challenges and dilemmas. It is our deepest conviction that life has an absolute value and that there always remains something indestructible and substantial in life, which may neither be evaluated by anything final, nor completely reduced to the material biological equivalent and the genetic substratum.


Assuntos
Início da Vida Humana , Vida , Humanos , Pessoalidade , Filosofia , Teologia
3.
J Neuroinflammation ; 19(1): 233, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36151564

RESUMO

BACKGROUND: The spleen, a substantial reservoir of non-differentiated monocytes, may play a crucial role in the pathophysiology of post-ischemic inflammation and influence outcomes after ischemic stroke. AIM OF THE STUDY: To analyze splenectomy as a preclinical intervention in murine models of ischemic stroke. METHODS: Following systematic searches of PubMed, Scopus and Web of Science, a qualitative synthesis of study characteristics was performed, and the effect of splenectomy estimated by a three-level random-effects meta-analysis of infarct volumes and a conventional two-level random-effects meta-analysis of neurological deficit scores. RESULTS: Database searches identified a total of 14 studies, 13 of which were used for meta-analysis. The ischemic lesion volumes were reduced in splenectomized animals compared to the control groups (difference in standardized mean differences: - 1.42; 95% CI [- 1.98, - 0.85]; 95% PI [- 2.03, - 0.80]; I2(2) = 19.04%; 95% CI [0.00%, 65.49%]; I2(3) = 47.24%; 95% CI [0.00%, 85.23%]) and neurological deficit scores were improved (- 1.20; 95% CI [- 2.20, - 0.20]; 95% PI [- 4.58, 2.18]; I2 = 77.5%; 95% CI [50.0%, 89.9%]). A subgroup analysis for infarct volumes showed that splenectomy performed prior to ischemia achieved a higher reduction of the ischemic lesion than when splenectomy was performed immediately prior or after stroke. Although the overall effect size of splenectomy could be classified as large, there was a significant presence of risks of bias, study heterogeneity, and a potential presence of publication bias. CONCLUSION: Despite limitations related to heterogeneity, risks of bias, and potential publication bias, this meta-analysis points to the spleen and its functional cell populations as promising targets for the therapeutic modulation of post-stroke inflammation.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Isquemia Encefálica/cirurgia , Modelos Animais de Doenças , Infarto , Inflamação , AVC Isquêmico/cirurgia , Camundongos , Esplenectomia , Acidente Vascular Cerebral/tratamento farmacológico
4.
Croat Med J ; 63(6): 515-524, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36597563

RESUMO

AIM: To test the agreement between a newly developed micro-magnetic resonance imaging (MRI) analysis of the subchondral bone and the micro-computed tomography (CT) approach. METHODS: Samples obtained from 10 patients with osteoarthritis undergoing total hip arthroplasty were scanned with a 7.0 T micro-MRI. Proton density-weighted images and proton density-weighted images with fat suppression were obtained. The results were validated with a micro-CT device. Micro-MRI and micro-CT scans of the same sample were aligned, and regions of interest were delineated on equal areas of the sample. Bone volume fraction was calculated by using in-house plugins. The agreement between the methods was tested with Bland-Altman analysis. RESULTS: The agreement between the methods was good, with average difference of 2.167%. The differences between the methods were not significant (P=0.272, t test). CONCLUSION: The novel micro-MRI approach could be used for subchondral bone analysis. With further optimization for clinical MRI machines, the approach can be also used in the diagnostics of hip osteoarthritis.


Assuntos
Osteoartrite do Quadril , Humanos , Osteoartrite do Quadril/diagnóstico por imagem , Osteoartrite do Quadril/cirurgia , Microtomografia por Raio-X/métodos , Osso Esponjoso , Prótons , Imageamento por Ressonância Magnética
5.
Psychiatr Danub ; 33(3): 287-291, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34795163

RESUMO

By discussing the position of bio-conservatism and transhumanism, we question if the women menstrual cycle control would represent a new way toward a more responsive relation with one's own physical and mental health, a choice of freedom from undesired physiological conditions, a medicalization of a natural physiological event or an innovative carrier of social stigma against the women. We argue that the advancement of medical science may allow women a choice if to regulate own menstrual cycle, offering them as well a right to intervene responsibly on their own body and psyche. Accordingly, a post-human society could provide a suitable coexistence between women who claim menstruation as the biological essence and those who claim it as an option.


Assuntos
Ciclo Menstrual , Menstruação , Feminino , Humanos
6.
J Med Internet Res ; 22(8): e17051, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32442138

RESUMO

BACKGROUND: Online interactions within a closed WhatsApp group can influence the attitudes and behaviors of the users in relation to health issues. OBJECTIVE: This study aimed to analyze the activity of the members of a WhatsApp group initiated to raise awareness of the possible health effects of 5G mobile networks and mobilize members to sign the related petition. METHODS: We retrospectively analyzed data from the WhatsApp group of 205 members that was active during 4 consecutive days in August 2019. The messages exchanged were collected, anonymized, and analyzed according to their timing and content. RESULTS: The WhatsApp group members were invited to the group from the administrator's contacts; 91% (187/205) had a university degree, 68% (140/205) were medical professionals, and 24% (50/205) held academic positions. Approximately a quarter of the members (47/205, 23%) declared in their messages they signed the corresponding petition. The intense message exchange had wildfire-like features, and the majority of messages (126/133, 95%) were exchanged during the first 26 hours. Despite the viral activity and high rate of members openly declaring that they signed the petition, only 8 (8/133, 6%) messages from the group members, excluding the administrator, referred to the health issue, which was the topic of the group. No member expressed an opposite opinion to those presented by the administrator, and there was no debate in the form of exchanging opposite opinions. CONCLUSIONS: The wildfire-like activity of the WhatsApp group and open declaration of signing the petition as a result of the mobilization campaign were not accompanied by any form of a debate related to the corresponding health issue, although the group members were predominantly health professionals, with a quarter of holding academic positions.


Assuntos
Pessoal de Saúde/educação , Mídias Sociais/normas , Feminino , Pessoal de Saúde/normas , Humanos , Masculino , Estudos Retrospectivos
7.
Int J Mol Sci ; 20(20)2019 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-31635131

RESUMO

High salt (HS) dietary intake leads to impaired vascular endothelium-dependent responses to various physiological stimuli, some of which are mediated by arachidonic acid (AA) metabolites. Transgenic Tff3-/- gene knockout mice (Tff3-/-/C57BL/6N) have changes in lipid metabolism which may affect vascular function and outcomes of stroke. We aimed to study the effects of one week of HS diet (4% NaCl) on vascular function and stroke induced by transient occlusion of middle cerebral artery in Tff3-/- and wild type (WT/C57BL/6N) mice. Flow-induced dilation (FID) of carotid artery was reduced in WT-HS mice, but not affected in Tff3-/--HS mice. Nitric oxide (NO) mediated FID. NO production was decreased with HS diet. On the contrary, acetylcholine-induced dilation was significantly decreased in Tff3-/- mice on both diets and WT-HS mice. HS intake and Tff3 gene depletion affected the structural components of the vessels. Proteomic analysis revealed a significant effect of Tff3 gene deficiency on HS diet-induced changes in neuronal structural proteins and acute innate immune response proteins' expression and Tff3 depletion, but HS diet did not increase the stroke volume, which is related to proteome modification and upregulation of genes involved mainly in cellular antioxidative defense. In conclusion, Tff3 depletion seems to partially impair vascular function and worsen the outcomes of stroke, which is moderately affected by HS diet.


Assuntos
Circulação Cerebrovascular/efeitos dos fármacos , Cloreto de Sódio na Dieta/farmacologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/fisiopatologia , Fator Trefoil-3/deficiência , Animais , Biomarcadores , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Dieta , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/genética , Endotélio Vascular/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/metabolismo , Proteoma , Fluxo Sanguíneo Regional , Fatores de Transcrição/metabolismo , Vasodilatação/efeitos dos fármacos
8.
J Synchrotron Radiat ; 25(Pt 4): 1153-1161, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29979177

RESUMO

Synchrotron radiation micro-computed tomography (SRµCT) based virtual histology, in combination with dedicated ex vivo staining protocols and/or phase contrast, is an emerging technology that makes use of three-dimensional images to provide novel insights into the structure of tissue samples at microscopic resolution with short acquisition times of the order of minutes or seconds. However, the high radiation dose creates special demands on sample preparation and staining. As a result of the lack of specific staining in virtual histology, it can supplement but not replace classical histology. Therefore, the aim of this study was to establish and compare optimized ex vivo staining and acquisition protocols for SRµCT-based virtual histology of soft-tissue samples, which could be integrated into the standard workflow of classical histology. The high grade of coherence of synchrotron radiation allows the application of propagation-based phase contrast imaging (PBI). In this study, PBI yielded a strong increase in image quality even at lower radiation doses and consequently prevented any damage to the tissue samples or the embedding material. This work has demonstrated that the improvement in contrast-to-noise ratio by PBI enabled label-free virtual histology of soft-tissue specimens embedded in paraffin to a level of detail that exceeds that achieved with staining protocols.


Assuntos
Encéfalo/anatomia & histologia , Carcinoma Ductal Pancreático/patologia , Coração/anatomia & histologia , Pulmão/anatomia & histologia , Neoplasias Pancreáticas/patologia , Coloração e Rotulagem , Síncrotrons , Microtomografia por Raio-X/métodos , Animais , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doses de Radiação
9.
Mol Cell Neurosci ; 67: 104-15, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26101075

RESUMO

STAM2 (signal transducing adaptor molecule 2), a subunit of the ESCRT-0 complex, is an endosomal protein acting as a regulator of receptor signaling and trafficking. To analyze STAM2 in the nervous system, its gene expression and protein localization in the mouse brain were identified using three methods: mRNA in situ hybridization, immunohistochemistry, and via lacZ reporter in frame with Stam2 gene using the gene trap mouse line Stam2(Gt1Gaj). STAM2 intracellular localization was analyzed by subcellular fractionation and co-immunofluorescence using confocal microscopy. Stam2 was strongly expressed in the cerebral and cerebellar cortex, hippocampal formation, olfactory bulb, and medial habenula. The majority of STAM2-positive cells co-stained with the neuronal markers. In neurons STAM2 was found in the early endosomes and also in the nucleus. The other members of the ESCRT-0 complex co-localized with STAM2 in the cytoplasm, but they were not present in the nucleus. The newly identified neuron-specific nuclear localization of STAM2, together with its high expression in the brain indicated that STAM2 might have a specific function in the mouse nervous system.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Neurônios/metabolismo , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Núcleo Celular/metabolismo , Células Cultivadas , Cerebelo/metabolismo , Citoplasma/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Bulbo Olfatório/metabolismo , Especificidade de Órgãos , Fosfoproteínas/genética , Transporte Proteico
11.
Mol Biol Evol ; 30(4): 844-52, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23197593

RESUMO

The FOXP2 gene is required for normal development of speech and language. By isolating and sequencing FOXP2 genomic DNA fragments from a 49,000-year-old Iberian Neandertal and 50 present-day humans, we have identified substitutions in the gene shared by all or nearly all present-day humans but absent or polymorphic in Neandertals. One such substitution is localized in intron 8 and affects a binding site for the transcription factor POU3F2, which is highly conserved among vertebrates. We find that the derived allele of this site is less efficient than the ancestral allele in activating transcription from a reporter construct. The derived allele also binds less POU3F2 dimers than POU3F2 monomers compared with the ancestral allele. Because the substitution in the POU3F2 binding site is likely to alter the regulation of FOXP2 expression, and because it is localized in a region of the gene associated with a previously described signal of positive selection, it is a plausible candidate for having caused a recent selective sweep in the FOXP2 gene.


Assuntos
Evolução Molecular , Fatores de Transcrição Forkhead/genética , Elementos Reguladores de Transcrição , Animais , Sequência de Bases , Sítios de Ligação , Sequência Conservada , Fatores de Transcrição Forkhead/metabolismo , Frequência do Gene , Células HeLa , Proteínas de Homeodomínio/química , Proteínas de Homeodomínio/metabolismo , Humanos , Íntrons , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Dados de Sequência Molecular , Homem de Neandertal/genética , Fatores do Domínio POU/química , Fatores do Domínio POU/metabolismo , Análise de Sequência de DNA , Ativação Transcricional
12.
Front Neuroinform ; 18: 1358917, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38595906

RESUMO

Introduction: Magnetic resonance imaging (MRI) is invaluable for understanding brain disorders, but data complexity poses a challenge in experimental research. In this study, we introduce suMRak, a MATLAB application designed for efficient preclinical brain MRI analysis. SuMRak integrates brain segmentation, volumetry, image registration, and parameter map generation into a unified interface, thereby reducing the number of separate tools that researchers may require for straightforward data handling. Methods and implementation: All functionalities of suMRak are implemented using the MATLAB App Designer and the MATLAB-integrated Python engine. A total of six helper applications were developed alongside the main suMRak interface to allow for a cohesive and streamlined workflow. The brain segmentation strategy was validated by comparing suMRak against manual segmentation and ITK-SNAP, a popular open-source application for biomedical image segmentation. Results: When compared with the manual segmentation of coronal mouse brain slices, suMRak achieved a high Sørensen-Dice similarity coefficient (0.98 ± 0.01), approaching manual accuracy. Additionally, suMRak exhibited significant improvement (p = 0.03) when compared to ITK-SNAP, particularly for caudally located brain slices. Furthermore, suMRak was capable of effectively analyzing preclinical MRI data obtained in our own studies. Most notably, the results of brain perfusion map registration to T2-weighted images were shown, improving the topographic connection to anatomical areas and enabling further data analysis to better account for the inherent spatial distortions of echoplanar imaging. Discussion: SuMRak offers efficient MRI data processing of preclinical brain images, enabling researchers' consistency and precision. Notably, the accelerated brain segmentation, achieved through K-means clustering and morphological operations, significantly reduces processing time and allows for easier handling of larger datasets.

13.
JMIR Hum Factors ; 11: e44258, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373020

RESUMO

BACKGROUND: As the SARS-CoV-2 virus created a global pandemic and rapidly became an imminent threat to the health and lives of people worldwide, the need for a vaccine and its quick distribution among the population was evident. Due to the urgency, and on the back of international collaboration, vaccines were developed rapidly. However, vaccination rollouts showed different success rates in different countries and some also led to increased vaccine hesitancy. OBJECTIVE: The aim of this study was to identify the role of information sharing and context sensitivity in various vaccination programs throughout the initial COVID-19 vaccination rollout in different countries. Moreover, we aimed to identify factors in national vaccination programs related to COVID-19 vaccine hesitancy, safety, and effectiveness. Toward this end, multidisciplinary and multinational opinions from members of the Navigating Knowledge Landscape (NKL) network were analyzed. METHODS: From May to July 2021, 25 completed questionnaires from 27 NKL network members were collected. These contributors were from 17 different countries. The responses reflected the contributors' subjective viewpoints on the status and details of the COVID-19 vaccination rollout in their countries. Contributors were asked to identify strengths, weaknesses, opportunities, and threats (ie, SWOT) of the respective vaccination programs. The responses were analyzed using reflexive thematic analysis, followed by frequency analysis of identified themes according to the represented countries. RESULTS: The perspectives of NKL network members showed a link between organizational elements of the vaccination rollout and the accompanying societal response, both of which were related to strengths and weaknesses of the process. External sociocultural variables, improved public communication around vaccination-related issues, ethical controversies, and the spread of disinformation were the dominant themes related to opportunities and challenges. In the SWOT 2×2 matrix, Availability and Barriers emerged as internal categories, whereas Transparent communication and promotion and Societal divide emerged as key external categories. CONCLUSIONS: Inventory of themes and categories inspired by elements of the SWOT framework provides an informative multidisciplinary perspective for effective implementation of public health strategies in the battle against COVID-19 or any future pandemics of a similar nature.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Vacinas contra COVID-19/uso terapêutico , COVID-19/epidemiologia , SARS-CoV-2 , Vacinação , Comunicação
17.
Croat Med J ; 54(1): 3-11, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23444240

RESUMO

AIM: To explore the possibility of brain imaging by microcomputed tomography (microCT) using x-ray contrasting methods to visualize mouse brain ischemic lesions after middle cerebral artery occlusion (MCAO). METHODS: Isolated brains were immersed in ionic or nonionic radio contrast agent (RCA) for 5 days and subsequently scanned using microCT scanner. To verify whether ex-vivo microCT brain images can be used to characterize ischemic lesions, they were compared to Nissl stained serial histological sections of the same brains. To verify if brains immersed in RCA may be used afterwards for other methods, subsequent immunofluorescent labeling with anti-NeuN was performed. RESULTS: Nonionic RCA showed better gray to white matter contrast in the brain, and therefore was selected for further studies. MicroCT measurement of ischemic lesion size and cerebral edema significantly correlated with the values determined by Nissl staining (ischemic lesion size: P=0.0005; cerebral edema: P=0.0002). Brain immersion in nonionic RCA did not affect subsequent immunofluorescent analysis and NeuN immunoreactivity. CONCLUSION: MicroCT method was proven to be suitable for delineation of the ischemic lesion from the non-infarcted tissue, and quantification of lesion volume and cerebral edema.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Meios de Contraste , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Microtomografia por Raio-X , Animais , Edema Encefálico/patologia , Isquemia Encefálica/patologia , Corantes , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/patologia , Iohexol , Ácido Iotalâmico/análogos & derivados , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Coloração e Rotulagem
18.
Sci Rep ; 13(1): 8539, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37237015

RESUMO

The aim of this study was to characterize expression of corticogenesis-related transcription factors BCL11B and SATB2 after brain ischemic lesion in the adult mice, and to analyze their correlation to the subsequent brain recovery. Ischemic brain lesion was induced by transient middle cerebral artery occlusion followed by reperfusion, and the animals with ischemic lesion were compared to the sham controls. Progression of the brain damage and subsequent recovery was longitudinally monitored structurally, by magnetic resonance imaging, and functionally, by neurological deficit assessment. Seven days after the ischemic injury the brains were isolated and analyzed by immunohistochemistry. The results showed higher expression in the brain of both, BCL11B and SATB2 in the animals with ischemic lesion compared to the sham controls. The co-expression of both markers, BCL11B and SATB2, increased in the ischemic brains, as well as the co-expression of BCL11B with the beneficial transcriptional factor ATF3 but not its co-expression with detrimental HDAC2. BCL11B was mainly implicated in the ipsilateral and SATB2 in the contralateral brain hemisphere, and their level in these regions correlated with the functional recovery rate. The results indicate that the reactivation of corticogenesis-related transcription factors BCL11B and SATB2 is beneficial after brain ischemic lesion.


Assuntos
Isquemia Encefálica , Fatores de Transcrição , Camundongos , Animais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Encéfalo/metabolismo , Isquemia Encefálica/patologia , Infarto da Artéria Cerebral Média/patologia , Proteínas Supressoras de Tumor/metabolismo , Modelos Animais de Doenças , Proteínas Repressoras/metabolismo
19.
Front Endocrinol (Lausanne) ; 14: 1181064, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37929025

RESUMO

Aim/Introduction: The study aimed to determine the effectiveness of early antidiabetic therapy in reversing metabolic changes caused by high-fat and high-sucrose diet (HFHSD) in both sexes. Methods: Elderly Sprague-Dawley rats, 45 weeks old, were randomized into four groups: a control group fed on the standard diet (STD), one group fed the HFHSD, and two groups fed the HFHSD along with long-term treatment of either metformin (HFHSD+M) or liraglutide (HFHSD+L). Antidiabetic treatment started 5 weeks after the introduction of the diet and lasted 13 weeks until the animals were 64 weeks old. Results: Unexpectedly, HFHSD-fed animals did not gain weight but underwent significant metabolic changes. Both antidiabetic treatments produced sex-specific effects, but neither prevented the onset of prediabetes nor diabetes. Conclusion: Liraglutide vested benefits to liver and skeletal muscle tissue in males but induced signs of insulin resistance in females.


Assuntos
Liraglutida , Síndrome Metabólica , Metformina , Animais , Feminino , Masculino , Ratos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Liraglutida/uso terapêutico , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/etiologia , Metformina/uso terapêutico , Ratos Sprague-Dawley , Sacarose/efeitos adversos , Fatores Sexuais
20.
J Neuroinflammation ; 9: 191, 2012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22873409

RESUMO

BACKGROUND: Using a live imaging approach, we have previously shown that microglia activation after stroke is characterized by marked and long-term induction of the Toll-like receptor (TLR) 2 biophotonic signals. However, the role of TLR2 (and potentially other TLRs) beyond the acute innate immune response and as early neuroprotection against ischemic injury is not well understood. METHODS: TLR2-/- mice were subjected to transient middle cerebral artery occlusion followed by different reperfusion times. Analyses assessing microglial activation profile/innate immune response were performed using in situ hybridization, immunohistochemistry analysis, flow cytometry and inflammatory cytokine array. The effects of the TLR2 deficiency on the evolution of ischemic brain injury were analyzed using a cresyl violet staining of brain sections with appropriate lesion size estimation. RESULTS: Here we report that TLR2 deficiency markedly affects post-stroke immune response resulting in delayed exacerbation of the ischemic injury. The temporal analysis of the microglia/macrophage activation profiles in TLR2-/- mice and age-matched controls revealed reduced microglia/macrophage activation after stroke, reduced capacity of resident microglia to proliferate as well as decreased levels of monocyte chemotactic protein-1 (MCP-1) and consequently lower levels of CD45(high)/CD11b(+) expressing cells as shown by flow cytometry analysis. Importantly, although acute ischemic lesions (24 to 72 h) were smaller in TLR2-/- mice, the observed alterations in innate immune response were more pronounced at later time points (at day 7) after initial stroke, which finally resulted in delayed exacerbation of ischemic lesion leading to larger chronic infarctions as compared with wild-type mice. Moreover, our results revealed that TLR2 deficiency is associated with significant decrease in the levels of neurotrophic/anti-apoptotic factor Insulin-like growth factor-1 (IGF-1), expressed by microglia in the areas both in and around ischemic lesion. CONCLUSION: Our results clearly suggest that optimal and timely microglial activation/innate immune response is needed to limit neuronal damage after stroke.


Assuntos
Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Receptor 2 Toll-Like/deficiência , Animais , Isquemia Encefálica/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/metabolismo , Microglia/patologia , Fatores de Tempo , Receptor 2 Toll-Like/biossíntese , Receptor 2 Toll-Like/genética
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