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1.
Cell Biochem Funct ; 42(4): e4059, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38773900

RESUMO

Cerebral ischemic stroke remains a leading cause of mortality and morbidity worldwide. Toll-like receptor 4 (TLR4) has been implicated in neuroinflammatory responses poststroke, particularly in the infiltration of immune cells and polarization of macrophages. This study aimed to elucidate the impact of TLR4 deficiency on neutrophil infiltration and subsequent macrophage polarization after middle cerebral artery occlusion (MCAO), exploring its role in stroke prognosis. The objective was to investigate how TLR4 deficiency influences neutrophil behavior poststroke, its role in macrophage polarization, and its impact on stroke prognosis using murine models. Wild-type and TLR4-deficient adult male mice underwent MCAO induction, followed by various analyses, including flow cytometry to assess immune cell populations, bone marrow transplantation experiments to evaluate TLR4-deficient neutrophil behaviors, and enzyme-linked immunosorbent assay and Western blot analysis for cytokine and protein expression profiling. Neurobehavioral tests and infarct volume analysis were performed to assess the functional and anatomical prognosis poststroke. TLR4-deficient mice exhibited reduced infarct volumes, increased neutrophil infiltration, and reduced M1-type macrophage polarization post-MCAO compared to wild-type mice. Moreover, the depletion of neutrophils reversed the neuroprotective effects observed in TLR4-deficient mice, suggesting the involvement of neutrophils in mediating TLR4's protective role. Additionally, N1-type neutrophils were found to promote M1 macrophage polarization via neutrophil gelatinase-associated lipocalin (NGAL) secretion, a process blocked by TLR4 deficiency. The study underscores the protective role of TLR4 deficiency in ischemic stroke, delineating its association with increased N2-type neutrophil infiltration, diminished M1 macrophage polarization, and reduced neuroinflammatory responses. Understanding the interplay between TLR4, neutrophils, and macrophages sheds light on potential therapeutic targets for stroke management, highlighting TLR4 as a promising avenue for intervention in stroke-associated neuroinflammation and tissue damage.


Assuntos
Macrófagos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos , Receptor 4 Toll-Like , Animais , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/deficiência , Camundongos , Masculino , Macrófagos/metabolismo , Macrófagos/imunologia , Prognóstico , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Neutrófilos/metabolismo , Neutrófilos/imunologia
2.
World J Clin Cases ; 11(27): 6543-6550, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37900223

RESUMO

BACKGROUND: Stroke is the second and third leading cause of death and disability, respectively. To date, no definitive treatment can repair lost brain function. Recently, various preclinical studies have been reported on mesenchymal stromal cells (MSCs) and their derivatives and their potential as alternative therapies for stroke. CASE SUMMARY: A 45-year-old female suffered an acute stroke, which led to paralysis in the left upper and lower limbs. The amniotic membrane MSC-derived secretome (MSC-secretome) was intravenously transplanted once a week for 4 wk. MSC-secretome-regulated regulatory T cells were investigated for the beneficial effects. The clinical improvement of this patient was accompanied by an increased frequency of regulatory T cells after transplantation. CONCLUSION: Intravenous administration of MSC-secretome can potentially treat patients who suffer from acute ischemic stroke.

3.
Brain Behav ; 13(5): e3003, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37060179

RESUMO

OBJECTIVE: To describe the clinical and radiological characteristics of anti-metabotropic glutamate receptor 5 (mGluR5) encephalitis. METHODS: We reviewed the clinical data of five patients with anti-mGluR5 encephalitis, and performed a literature review. RESULTS: The five cases included a 52-year-old man who developed a biphasic course of anti-mGluR5 encephalitis after herpes simplex encephalitis, a 22-year-old woman who showed bilateral basal ganglia lesions on brain magnetic resonance imaging (MRI), and a 36-year-old man with mixed aphasia and generalized tonic-clonic seizures, a 51-year-old man presented with personality changes, hallucinations, delusions, sleeping disorders and a 58-year-old man with short-term memory deficits and absence seizures.. There are 16 reported cases of anti-mGluR5 encephalitis worldwide. Of all 21 patients, with a median onset age of 35 years old, the main neurological symptoms were cognitive impairment (85.7%, 18/21), psychiatric or behavior problems (76.2%, 16/21), seizures (57.1%, 12/21), sleeping disorders (52.4%, 11/21), different degrees of decreased consciousness (42.9%, 9/21), and movement disorders (23.8%, 5/21). Brain MRI was normal in 11 of 21 patients. Lesions of the limbic lobes were presented in 5 patients, while involvement of other extralimbic regions was also reported. Seven of 21 (33.3%) cases were combined with tumors. Elevated white blood cell counts or specific oligoclonal IgG bands in the cerebrospinal fluid were found in 18 of 21 patients, with marked improvements observed after immunotherapy. DISCUSSION: Patients with anti-mGluR5 encephalitis typically present with diffuse, rather than purely limbic, encephalitis. Anti-mGluR5 encephalitis can be triggered by herpes simplex encephalitis. The risk of a combined tumor may be reduced in anti-mGluR5 encephalitis patients.


Assuntos
Encefalite por Herpes Simples , Encefalite Límbica , Transtornos dos Movimentos , Masculino , Feminino , Humanos , Adulto , Adulto Jovem , Pessoa de Meia-Idade , Encefalite por Herpes Simples/diagnóstico por imagem , Encefalite por Herpes Simples/tratamento farmacológico , Encefalite por Herpes Simples/complicações , Encéfalo , Encefalite Límbica/complicações , Convulsões/etiologia , Transtornos dos Movimentos/complicações , Imageamento por Ressonância Magnética
4.
Front Cell Dev Biol ; 10: 822772, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252190

RESUMO

Adipose-derived stem cells (ADSCs) are able to modulate the immune response and are used for treating ulcerative colitis (UC). However, it is possible that ADSCs from patients with inflammatory or autoimmune disorders may show defective immunosuppression. We investigated the use of ADSCs from UC patients for autologous cell treatment, specifically, ADSCs from healthy donors (H-ADSCs) and UC patients (P-ADSCs) in terms of various functions, including differentiation, proliferation, secretion, and immunosuppression. The efficacy of P-ADSCs for treating UC was examined in mouse models of acute or chronic colitis. Both H-ADSCs and P-ADSCs were similar in cell morphology, size, adipogenic differentiation capabilities, and cell surface markers. We found that P-ADSCs had lower proliferative capacity, cloning ability, and osteogenic and chondrogenic differentiation potential than H-ADSCs. P-ADSCs exhibited a diminished capacity to inhibit peripheral blood mononuclear cell proliferation, suppress CD25 and CD69 marker expression, decrease the production of inflammation-associated cytokines interferon-γ and tumor necrosis factor-α, and reduce their cytotoxic effect on A549 cells. When primed with inflammatory cytokines, P-ADSCs secreted lower levels of prostaglandin E2, indoleamine 2, 3-dioxygenase, and tumor necrosis factor-α-induced protein 6, which mediated their reduced immunopotency. Moreover, P-ADSCs exhibited weaker therapeutic effects than H-ADSCs, determined by disease activity, histology, myeloperoxidase activity, and body weight. These findings indicate that the immunosuppressive properties of ASCs are affected by donor metabolic characteristics. This study shows, for the first time, the presence of defective ADSC immunosuppression in UC, indicating that autologous transplantation of ADSCs may be inappropriate for patients with UC.

5.
Sensors (Basel) ; 18(2)2018 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-29495252

RESUMO

Social applications play a very important role in people's lives, as users communicate with each other through social networks on a daily basis. This presents a challenge: How does one receive high-quality service from social networks at a low cost? Users can access different kinds of wireless networks from various locations. This paper proposes a user access management strategy based on network pricing such that networks can increase its income and improve service quality. Firstly, network price is treated as an optimizing access parameter, and an unascertained membership algorithm is used to make pricing decisions. Secondly, network price is adjusted dynamically in real time according to network load. Finally, selecting a network is managed and controlled in terms of the market economy. Simulation results show that the proposed scheme can effectively balance network load, reduce network congestion, improve the user's quality of service (QoS) requirements, and increase the network's income.

6.
Saudi J Biol Sci ; 25(2): 237-241, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29472771

RESUMO

Fog computing is a distributed computing paradigm at the edge of the network and requires cooperation of users and sharing of resources. When users in fog computing open their resources, their devices are easily intercepted and attacked because they are accessed through wireless network and present an extensive geographical distribution. In this study, a credible third party was introduced to supervise the behavior of users and protect the security of user cooperation. A fog computing security mechanism based on human nervous system is proposed, and the strategy for a stable system evolution is calculated. The MATLAB simulation results show that the proposed mechanism can reduce the number of attack behaviors effectively and stimulate users to cooperate in application tasks positively.

7.
Biochem Biophys Res Commun ; 406(1): 152-7, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21303658

RESUMO

The lack of disease-modifying pharmacological agents for effective treatment of multiple sclerosis (MS) still represents a large and urgent unmet medical need. Our previous studies showed that ligands to type 2 imidazoline receptors (I(2)R) were effective in protecting spinal cord injury caused by experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. In this study, we further examined the protective property of a very selective ligand of I(2)R, 2-(2-benzofuranyl) 2-imidazoline (2-BFI) against EAE. Importantly, a mechanism of 2-BFI-mediated protection was investigated which possibly involves an I(2)R binding protein, brain-creatine kinase (B-CK), as well as CaATPase and calpain. The enzymatic activity of B-CK and CaATPase was significantly reduced in EAE injured spinal cord. Reduction of B-CK activity in EAE spinal cord may lead to energy reduction and dysfunction in cellular calcium homeostasis. Increased intracellular calcium evokes elevation of calpain activity occurring in EAE spinal cord which causes further tissue damage. Indeed, EAE injured spinal cord showed significant reduction in CaATPase and increase calpain activities. Remarkably, spinal cord tissue from mice treated daily with 2-BFI during the progression of EAE significantly restored B-CK and CaATPase enzymatic activities and showed no induction in calpain activity. Moreover, EAE spinal cord from 2-BFI treated mice also demonstrated better preservation of myelin; reduced axonal injury, as evidenced by the lower level of ß-APP expression, and above all, highly improved neurobehavioral scores (p<0.01; n=10). These findings suggest that 2-BFI can be further developed as a therapeutic drug for MS treatment.


Assuntos
Benzofuranos/uso terapêutico , Encefalomielite Autoimune Experimental/tratamento farmacológico , Imidazóis/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Animais , Axônios/efeitos dos fármacos , Axônios/patologia , ATPases Transportadoras de Cálcio/biossíntese , Calpaína/antagonistas & inibidores , Creatina Quinase Forma BB/biossíntese , Encefalomielite Autoimune Experimental/enzimologia , Encefalomielite Autoimune Experimental/etiologia , Encefalomielite Autoimune Experimental/patologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/enzimologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/enzimologia
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