RESUMO
BACKGROUND: Current options to treat clinical relapse in inflammatory central nervous system (CNS) conditions such as cerebral ischemia-reperfusion injury are limited, and agents that are more effective are required. Disruption of the blood-brain barrier is an early feature of lesion formation that correlates with clinical exacerbation and facilitates the entry of inflammatory medium and inflammatory cells. Interleukin-1 receptor antagonist (IL-1RA) is a naturally occurring anti-inflammatory antagonist of the interleukin-1 (IL-1) family. The broad-spectrum anti-inflammatory effects of IL-1RA have been investigated against various forms of neuroinflammation. However, the effect of IL-1RA on blood-brain barrier disruption following ischemia-reperfusion has not been reported. METHODS: In this study, we investigated the effects of IL-1RA and a novel protein (IL-1RA-PEP) that was fused to IL-1RA with a cell penetrating peptide, on blood-brain barrier integrity, in male rats subjected to transient middle cerebral artery occlusion. RESULTS: After intravenous administration, IL-1RA-PEP (50 mg/kg) penetrated cerebral tissues more effectively than IL-1RA. Moreover, it preserved blood-brain barrier integrity, attenuated changes in expression and localization of tight junction proteins and matrix metalloproteinases, and enhanced angiogenesis in ischemic brain tissue. Further study suggested that the effects of IL-1RA-PEP on preserving blood-brain barrier integrity might be closely correlated with the p65/NF-κB pathway, as evidenced by the effects of the inhibitor JSH-23. CONCLUSIONS: Collectively, our results demonstrated that IL-1RA-PEP could effectively penetrate the brain of rats with middle cerebral artery occlusion and ameliorate blood-brain barrier disruption. This finding might represent its novel therapeutic potential in the treatment of the cerebral ischemia-reperfusion injury.
Assuntos
Barreira Hematoencefálica/metabolismo , Isquemia Encefálica/metabolismo , Cisteamina/análogos & derivados , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Peptídeos/metabolismo , Traumatismo por Reperfusão/metabolismo , Administração Intravenosa , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Cisteamina/administração & dosagem , Cisteamina/metabolismo , Proteína Antagonista do Receptor de Interleucina 1/administração & dosagem , Masculino , Peptídeos/administração & dosagem , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológicoRESUMO
PM2.5 exposure exacerbates cardiovascular diseases via oxidative stress and inflammation, the detailed mechanism of which is unclear. In this study, the effects of oxidative stress and inflammation, as well as vascular structure and function were studied by multiple PM2.5 exposure model of ApoE-/- mice. The results indicated that NO produced by iNOS not cNOS might play important roles in inducing vascular dysfunction after PM2.5 exposure. The occurrence order and causality among NO, other oxidative stress indicators and inflammation is explored by single PM2.5 exposure. The results showed that NO generated by iNOS occurred earlier than that of other oxidative stress indicators, which was followed by the increased inflammation. Inhibition of NOS could effectively block the raise of NO, oxidative stress and inflammation after PM2.5 exposure. All in all, we firstly confirmed that NO was the initiation factor of PM2.5 exposure-induced oxidative stress, which led to inflammation and the following vascular dysfunction.
Assuntos
Apolipoproteínas E/metabolismo , Inflamação/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Material Particulado/toxicidade , Animais , Apolipoproteínas E/genética , Western Blotting , Imuno-Histoquímica , Inflamação/genética , Interleucina-6/sangue , Masculino , Camundongos , Camundongos Mutantes , Óxido Nítrico Sintase Tipo II/genética , Estresse Oxidativo/efeitos dos fármacos , Fator de Necrose Tumoral alfa/sangueRESUMO
PM2.5 exposure aggravates type 2 diabetes, in which inflammatory factors play an important role. In this study, we aimed to explore the mechanisms responsible for aggravating diabetes after PM2.5 exposure, and study the roles of inflammatory factors in insulin-resistant type 2 diabetes. Our study indicated that short-time PM2.5 exposure enhances insulin resistance in type 2 diabetic rats and significantly raises inflammatory factors, including IL-6, TNF-α, and MCP-1, in lungs. However, we found that of these inflammatory factors only IL-6 levels are elevated in blood, liver, adipose tissue, and macrophages, but not in skeletal muscle. IL-6 induced activation of the STAT3/SOCS3 pathway in liver, but not other downstream pathways including STAT1, ERK1/2, and PI3K. Both STAT3 inhibition and IL-6 neutralization effectively alleviated the disorders of glucose metabolism after PM2.5 exposure. Taken together, this suggests that the systemic increase in IL-6 may play an important role in the deterioration of the type 2 diabetes via IL-6/STAT3/SOCS3 pathway in liver after short-time exposure to PM2.5. Besides, we unexpectedly found a stronger resistance to the PM2.5 exposure-induced increase in IL-6 in skeleton muscle than those of many other tissues.
Assuntos
Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 2/imunologia , Interleucina-6/sangue , Material Particulado/toxicidade , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Animais , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Resistência à Insulina , Fígado/efeitos dos fármacos , Fígado/imunologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/imunologia , Material Particulado/metabolismo , Ratos , Ratos Wistar , Transdução de SinaisRESUMO
Macrophage migration plays an essential role in immune system and is also involved in many pathological situations. However, the regulatory mechanism of macrophage migration remains to be elucidated due to its diverse responses to various stimuli. SAK-HV, a multifunctional protein possessing thrombolytic and lipid-lowering activity, can selectively induce the macrophage proliferation. Here, we reported SAK-HV significantly triggered RAW264.7 cells migration through its functional domain of SAK-mutant by activating both c-jun N-terminal kinases (JNK) and nuclear factor-κB (NF-κB) pathways. Meanwhile, SAK-HV upregulated the expression of some effector proteins, among which only the expression of Monocyte chemoattractant protein-1 (MCP-1) was inhibited by the blockade of JNK and NF-κB pathways. Further research showed that MCP-1 promoted migration ultimately by interacting with Chemokine (C-C motif) Receptor 2 (CCR2) in an autocrine manner. In summary, SAK-HV induced RAW264.7 cells migration through its SAK-mutant domain, during which MCP-1 chemokine mediated by JNK and NF-κB pathways played a key role. These results revealed a novel effect of SAK-HV on modulating macrophage migration and also deepened the understanding of its pharmacodynamics.
Assuntos
Movimento Celular/fisiologia , Quimiocina CCL2/metabolismo , Animais , Movimento Celular/genética , Quimiocina CCL2/genética , Ensaio de Imunoadsorção Enzimática , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Fosforilação/genética , Fosforilação/fisiologia , Células RAW 264.7 , RNA Interferente Pequeno/genética , Receptores CCR2/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Transfecção , Cicatrização/genética , Cicatrização/fisiologiaRESUMO
Neuroinflammation and oxidative stress are involved in cerebral ischemia-reperfusion, in which Interleukin 1 (IL-1), as an effective intervention target, is implicated. Interleukin-1 receptor antagonist (IL-1RA) is the natural inhibitor of IL-1, but blood-brain barrier (BBB) limits the brain penetration of intravenously administered IL-1RA, thereby restricting its therapeutic effect against neuroinflammation. In this study, we evaluated the potential effects of anti-inflammation and anti-oxidative stress of a novel protein IL-1RA-PEP, which fused IL-1RA with a cell penetrating peptide (CPP). Studies were carried out in transient middle cerebral artery occlusion (MCAO) in rats and oxygen glucose deprivation/reoxygenation (OGD/R) in primary cortical neurons. In MCAO rat model, IL-1RA-PEP (50mg/kg) injected i.v., penetrated BBB effectively, and alleviated brain infarction, cerebral edema, neurological deficit score and motor performance as well as inhibited the inflammatory cytokines expression. Furthermore, our results firstly showed that IL-1RA-PEP also regulated the oxidases expression, decreased the levels of NO, MDA and ROS. In addition, the inhibitory effects of IL-1RA-PEP on oxidative stress and inflammation were confirmed in rat cortical neurons induced by OGD/R, it reduced ROS, IL-6 and TNF-α. Further study showed that the effects of IL-1RA-PEP were closely associated with the NF-κB and p38 pathways which were proved respectively by their inhibitors JSH-23 and SB203580. Our results indicated that IL-1RA-PEP could effectively penetrate the brain of MCAO rats, alleviated the cerebral ischemia reperfusion injury by inhibiting neuroinflammation and oxidative stress, showing a great clinical potential for stroke.