RESUMO
OBJECTIVE: The aim of this study was to investigate the potential therapeutic effects of a newly discovered osteopontin-derived synthetic peptide "RSKKFRR" in a rat model of ischemic stroke. METHODS: A total of 24 male SD rats were randomly divided into three groups. The model of ischemic stroke was made up of the middle cerebral artery occlusion (MACO). The rats were divided into sham operation group (Sham), control group (MACO + PBS) and treatment group (MACO + OPNpt9), eight rats in each group. In the control group and the treatment group, PBS or OPNpt9 was injected into the nasal cavity after MACO once a day, and the area of new blood vessels and the recovery of nerve function were observed 14 days later. Whether the proliferation, migration and tube formation of HUVECs were promoted by OPNpt9 was tested. The expression levels of related proangiogenic factors were also detected. RESULTS: OPNpt9 was found to contribute to cerebral microvascular remodeling and neurological improvement in ischemic rats while promoting endothelial cell migration, proliferation and tube formation in vitro. These effects were mediated by activation of the p-ERK/MMP-9/VEGF pathway. CONCLUSION: In conclusion, OPNpt9 promotes angiogenesis and neurological recovery after ischemic stroke.
Assuntos
Encéfalo/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , AVC Isquêmico/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Osteopontina/farmacologia , Animais , Encéfalo/metabolismo , Movimento Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Neovascularização Fisiológica/fisiologia , Ratos , Ratos Sprague-Dawley , Teste de Desempenho do Rota-RodRESUMO
Schizophrenia is a complex mental illness with genetic heterogeneity, which is often accompanied by alterations in brain structure and function. The neurobiological mechanism of schizophrenia associated with heredity remains unknown. Recently, the development of trans-scale and multi-omics methods that integrate gene and imaging information sheds new light on the nature of schizophrenia. In this article, we summarized the results of brain structural and functional changes related to the specific single-nucleotide polymorphisms (SNPs) in the past decade, and the SNPs were divided into non-coding regions and coding regions, respectively. It is hoped that the relationship between SNPs and cerebral alterations can be displayed more clearly and intuitively, so as to provide fresh approaches for the discovery of potential biomarkers and the development of clinical accurate individualized treatment decision-making.
RESUMO
In recent years, the use of thrombolytic therapy for treating ischemia/reperfusion injury has resulted in damage to the self-regulatory mechanisms of the brain. This is due to the increased production of free radicals, excitatory amino acids and pro-inflammatory cytokines causing secondary damage to the brain. Simple thrombolytic therapy has not been the best approach for treating ischemia/reperfusion injury. Excessive perfusion leads to failure of the body's self-regulatory functions, which in turn increases the area of cerebral edema and aggravates cerebral ischemia. Previous studies have evaluated the satiety hormone leptin as a link between energy expenditure and obesity. Of note, leptin, which is involved in brain development, synaptic transmission and angiogenesis following ischemia/reperfusion injury, has been considered an important factor for treating ischemia/reperfusion injury. The present review outlines the discovery of leptin and discusses its association with cerebral ischemia/reperfusion.
RESUMO
Osteopontin (OPN) is a phosphorylated glycoprotein secreted into body fluids by various cell types. OPN contains arginine-glycine-aspartate (RGD) and serine-leucine-alanine-tyrosine (SLAY) motifs that bind to several integrins and mediate a wide range of cellular processes. In the present study, the proangiogenic effects of a 20-amino-acid OPN peptide (OPNpt20) containing RGD and SLAY motifs were examined in human umbilical vein endothelial cells (HUVECs) and in a rat focal cerebral ischemia model. OPNpt20 exerted robust proangiogenic effects in HUVECs by promoting proliferation, migration and tube formation. These effects were significantly reduced in OPNpt20-RAA (RGD->RAA)-treated cells, but only slightly reduced in OPNpt20-SLAA (SLAY->SLAA)-treated cells. Interestingly, a mutant peptide without both motifs failed to induce these proangiogenic processes, indicating that the RGD motif is crucial and that SLAY also has a role. In OPNpt20-treated HUVEC cultures, AKT and ERK signaling pathways were activated, but activation of these pathways and tube formation were suppressed by anti-αvß3 antibody, indicating that OPNpt20 stimulates angiogenesis via the αvß3-integrin/AKT and ERK pathways. The proangiogenic function of OPNpt20 was further confirmed in a rat middle cerebral artery occlusion model. Total vessel length and vessel densities were markedly greater in OPNpt20-treated ischemic brains, accompanied by induction of proangiogenic markers. Together, these results demonstrate that the 20-amino-acid OPN peptide containing RGD and SLAY motifs exerts proangiogenic effects, wherein both motifs have important roles, and these effects appear to contribute to the neuroprotective effects of this peptide in the postischemic brain.
Assuntos
Indutores da Angiogênese/farmacologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Osteopontina/química , Fragmentos de Peptídeos/farmacologia , Motivos de Aminoácidos , Indutores da Angiogênese/química , Animais , Encéfalo/irrigação sanguínea , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Integrina alfaVbeta3/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Fármacos Neuroprotetores/farmacologia , Oligopeptídeos/química , Fragmentos de Peptídeos/química , Ratos Sprague-DawleyRESUMO
Endoplasmic reticulum (ER) stress is a critical molecular mechanism involved in the pathogenesis of sepsis. Hence, strategies for alleviating this stress may be essential for preventing cardiovascular injuries under sepsis. Adiponectin is secreted by adipocytes and its levels are decreased in sepsis. The purpose of this study was to investigate the protective effects of adiponectin treatment on endothelial cells and its mechanism. Male Wistar rats underwent cecal ligation and puncture (CLP) before being treated with adiponectin (72 and 120 µg/kg). The levels of malondialdehyde (MDA) in plasma, histological structure, and apoptosis of endothelial cells were evaluated. In vitro, human umbilical vein endothelial cells (HUVECs) were treated with adiponectin at 10 and 20 µg/mL for 24 h after stimulation by lipopolysaccharide (LPS). The levels of reactive oxygen species (ROS), ultrastructure, rate of apoptosis, the expression of inositol-requiring enzyme 1α (IRE1α) protein, and its downstream molecules (78 kDa glucose-regulated protein (GRP78), C/EBP homologous protein (CHOP), and caspase-12) were detected. The results showed that the levels of MDA and ROS induced by CLP or LPS stimulation were increased. Furthermore, endothelial cell apoptosis was increased under sepsis. The IRE1α pathway was initiated, as evidenced by activated IRE1α, increased GRP78, and up-regulated CHOP and caspase-12 in HUVECs. Following treatment with adiponectin, the number of apoptotic endothelial cells was markedly decreased. These findings demonstrated that treatment with adiponectin decreased apoptosis of endothelial cells caused by sepsis by attenuating the ER stress IRE1α pathway activated by oxidative stress.
Assuntos
Adiponectina/farmacologia , Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/fisiologia , Células Endoteliais/efeitos dos fármacos , Sepse/patologia , Veias Umbilicais/citologia , Animais , Apoptose/fisiologia , Western Blotting , Células Cultivadas , Chaperona BiP do Retículo Endoplasmático , Células Endoteliais/metabolismo , Citometria de Fluxo , Humanos , Lipopolissacarídeos , Masculino , Malondialdeído/sangue , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Ratos Wistar , Espécies Reativas de Oxigênio/análise , Valores de Referência , Reprodutibilidade dos Testes , Sepse/prevenção & controle , Fatores de Tempo , Veias Umbilicais/efeitos dos fármacosRESUMO
Men with diabetic erectile dysfunction (ED) respond poorly to the currently available oral phosphodiesterase-5 inhibitors. Therefore, functional therapies for diabetic ED are needed. Stromal vascular fraction (SVF) and the adenovirus-mediated cartilage oligomeric matrix angiopoietin-1 (Ad-COMP-Ang1) gene are known to play critical roles in penile erection. We previously reported that SVF and Ad-COMP-Ang1 have only a short-term effect in restoring erectile function. Further improvements to ED therapy are needed for long-lasting effects. In the present study, we aimed to test if the combination of SVF and Ad-COMP-Ang1 could extend the erection effect in diabetic ED. We found that the combination therapy showed a long-term effect in restoring erectile function through enhanced penile endothelial and neural cell regeneration. Combination therapy with SVF and Ad-COMP-Ang1 notably restored cavernous endothelial cell numbers, pericyte numbers, endothelial cell-cell junctions, decreased cavernous endothelial cell permeability, and promoted neural regeneration for at least 4 weeks in diabetic mice. In summary, this is an initial description of the long-term effect of combination therapy with SVF and Ad-COMP-Ang1 in restoring erectile function through a dual effect on endothelial and neural cell regeneration. Such combination therapy may have therapeutic potential for the treatment of diabetic ED.
Assuntos
Angiopoietina-1/genética , Diabetes Mellitus Experimental/complicações , Disfunção Erétil/terapia , Terapia Genética/métodos , Transplante de Células-Tronco Mesenquimais , Ereção Peniana/fisiologia , Animais , Diabetes Mellitus Experimental/metabolismo , Endotélio Vascular/metabolismo , Disfunção Erétil/etiologia , Disfunção Erétil/metabolismo , Junções Intercelulares/metabolismo , Masculino , Camundongos , PermeabilidadeRESUMO
Osteopontin (OPN) is a secreted glycoprotein that is expressed in various tissues, including brain, and mediates a wide range of cellular activities. In a previous study, the authors observed the robust neuroprotective effects of recombinant OPN and of RGD and SLAYGLR-containing OPN-peptide icosamer (OPNpt20) in an animal model of transient focal ischemia, and demonstrated anti-inflammatory and pro-angiogenic effects of OPNpt20 in the postischemic brain. In the present study, we investigated the effects of OPNpt20 on the motility and phagocytic activity of BV2 cells (a microglia cell line). F-actin polymerization and cell motility were significantly enhanced in OPNpt20-treated BV2 cells, and numbers of filopodia-like processes increased and lamellipodia-like structures enlarged and thickened. In addition, treatment of cells with either of three mutant OPN icosamers containing mutation within RGD, SLAY, or RGDSLAY showed that the RGD and SLAY motifs of OPNpt20 play critical roles in the enhancement of cell motility, and the interaction between exogenous OPNpt20 and endogenous αv and α4 integrin and the activations of FAK, Erk, and Akt signaling pathways were found to be involved in the OPNpt20-mediated induction of cell motility. Furthermore, phagocytic activity of microglia was also significantly enhanced by OPNpt20 in a RGD and SLAY dependent manner. These results indicate OPNpt20 containing RGD and SLAY motifs triggers microglial motility and phagocytic activity and OPNpt20-integrin mediated signaling plays a critical role in these activities.
RESUMO
Osteopontin (OPN) is a phosphorylated glycoprotein possessing an arginine-glycine-aspartate (RGD)-motif, which binds to several cell surface integrins and mediates a wide range of cellular processes. Inductions of OPN have been reported in the postischemic brain, and the neuroprotective effects of OPN have been demonstrated in animal models of stroke. In the present study, we showed a robust neuroprotective effect of RGD-containing icosamer OPN peptide (OPNpt20) in a rat model of focal cerebral ischemia (middle cerebral artery occlusion, MCAO). Intranasally administered OPNpt20 reduced mean infarct volume by 79.7 % compared to the treatment-naïve MCAO control animals and markedly ameliorated neurological deficits. In addition, OPNpt20 significantly suppressed the inductions of iNOS and of inflammatory markers in postischemic brains and in primary microglial cultures, demonstrating anti-inflammatory effects. Administration of a mutant peptide, in which RGD was replaced by arginine-alanine-alanine (RAA), failed to suppress infarct volumes in MCAO animals and co-administration of OPNpt20 with anti-αvß3 integrin antibody failed to suppress iNOS induction in primary microglia culture, indicating that the RGD motif in OPNpt20 and endogenous αvß3 integrin play critical roles. Furthermore, pull-down assay revealed a direct binding between OPNpt20 and αvß3 integrin in primary microglia culture. Together, these results indicate that RGD-containing OPN icosamer has therapeutic potential in the postischemic brain and αvß3 integrin-mediated anti-inflammatory effect might be an underlying mechanism.
Assuntos
Isquemia Encefálica/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Integrina alfaVbeta3/metabolismo , Neuroproteção , Oligopeptídeos/administração & dosagem , Osteopontina/administração & dosagem , Osteopontina/uso terapêutico , Administração Intranasal , Sequência de Aminoácidos , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/fisiopatologia , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Células Cultivadas , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Microglia/efeitos dos fármacos , Microglia/metabolismo , Atividade Motora , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Nitritos/metabolismo , Osteopontina/química , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Isoformas de Proteínas/administração & dosagem , Isoformas de Proteínas/química , Isoformas de Proteínas/uso terapêutico , Ratos Sprague-Dawley , Fator de Transcrição STAT1/metabolismoRESUMO
Endoplasmic reticulum (ER) stress is a critical molecular mechanism involved in the pathogenesis of sepsis. Hence, strategies for alleviating this stress may be essential for preventing cardiovascular injuries under sepsis. Adiponectin is secreted by adipocytes and its levels are decreased in sepsis. The purpose of this study was to investigate the protective effects of adiponectin treatment on endothelial cells and its mechanism. Male Wistar rats underwent cecal ligation and puncture (CLP) before being treated with adiponectin (72 and 120 μg/kg). The levels of malondialdehyde (MDA) in plasma, histological structure, and apoptosis of endothelial cells were evaluated. In vitro, human umbilical vein endothelial cells (HUVECs) were treated with adiponectin at 10 and 20 μg/mL for 24 h after stimulation by lipopolysaccharide (LPS). The levels of reactive oxygen species (ROS), ultrastructure, rate of apoptosis, the expression of inositol-requiring enzyme 1α (IRE1α) protein, and its downstream molecules (78 kDa glucose-regulated protein (GRP78), C/EBP homologous protein (CHOP), and caspase-12) were detected. The results showed that the levels of MDA and ROS induced by CLP or LPS stimulation were increased. Furthermore, endothelial cell apoptosis was increased under sepsis. The IRE1α pathway was initiated, as evidenced by activated IRE1α, increased GRP78, and up-regulated CHOP and caspase-12 in HUVECs. Following treatment with adiponectin, the number of apoptotic endothelial cells was markedly decreased. These findings demonstrated that treatment with adiponectin decreased apoptosis of endothelial cells caused by sepsis by attenuating the ER stress IRE1α pathway activated by oxidative stress.
Assuntos
Humanos , Animais , Masculino , Veias Umbilicais/citologia , Apoptose/efeitos dos fármacos , Sepse/patologia , Células Endoteliais/efeitos dos fármacos , Adiponectina/farmacologia , Estresse do Retículo Endoplasmático/fisiologia , Valores de Referência , Células Cultivadas , Lipopolissacarídeos , Western Blotting , Espécies Reativas de Oxigênio/análise , Ratos Wistar , Apoptose/fisiologia , Microscopia Confocal , Células Endoteliais/metabolismo , Microscopia Eletrônica de Transmissão , Citometria de Fluxo , Malondialdeído/sangueRESUMO
High mobility group box 1 (HMGB1) is an endogenous danger signal molecule. In a previous report, we showed that HMGB1 is massively released during NMDA-induced acute damaging process in the postischemic brain and triggers inflammatory processes and induces neuronal apoptosis. We have also reported a robust neuroprotection of intranasally delivered HMGB1 siRNA in the postischemic rat brain (middle cerebral artery occlusion (MCAO), 60 min). In the present study, we investigated the therapeutic efficacy of intranasally delivered HMGB1 binding heptamer peptide (HBHP; HMSKPVQ), which was selected using a phage display approach, in the same stroke animal model. A pull-down assay using biotin-labeled HBHP showed that HBHP binds directly to HMGB1, specifically to HMGB1 A box, confirming HMGB1/HBHP interaction. HBHP significantly suppressed HMGB1-mediated neuronal cell death in primary cortical cultures and HMGB1/HBHP binding was detected in NMDA-conditioned culture media. However, a heptamer peptide composed of a scrambled sequence of the seven amino acids in HBHP failed to bind HMGB1 and had no protective effect. Furthermore, HBHP (300 ng) delivered intranasally at 30 min before MCAO significantly suppressed infarct volume in the postischemic rat brain (maximal reduction by 41.8±5.4%) and ameliorated neurological and behavioral deficits. In contrast, scrambled heptamer peptide had no protective effect at the same dose. Together these results suggest that intranasal HBHP ameliorates neuronal damage in the ischemic brain by binding HMGB1, which might inhibit the function of HMGB1 as an endogenous danger signal molecule.
Assuntos
Isquemia Encefálica/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Proteína HMGB1/metabolismo , Fármacos Neuroprotetores/farmacologia , Oligopeptídeos/farmacologia , Administração Intranasal , Animais , Encéfalo/patologia , Encéfalo/fisiopatologia , Isquemia Encefálica/etiologia , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Células Cultivadas , Infarto da Artéria Cerebral Média/complicações , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Oligopeptídeos/metabolismo , Oligopeptídeos/uso terapêutico , Biblioteca de Peptídeos , Ratos , Ratos Sprague-DawleyRESUMO
High mobility group box 1 (HMGB1) is a family of endogenous molecules that is released by necrotic cells and causes neuronal damages by triggering inflammatory processes. In the cerebral ischemic brain, sustained and regulated suppression of HMGB1 has been emerged as a therapeutic means to grant neuroprotection. HMGB1 consists of two HMG boxes (A and B) and an acidic C-terminal tail, and the A box peptide antagonistically competes with HMGB1 for its receptors. In the middle cerebral artery occlusion (MCAO) in rats, a murine model of transient cerebral ischemia, administration of HMGB1 A box intraparenchymally, after encapsulated in biodegradable gelatin microspheres (GMS), which enhances the stability of peptide inside and allows its sustained delivery, at 1 h, 3 h, or 6 h after MCAO, reduced mean infarct volumes by, respectively, 81.3%, 42.6% and 30.7% of the untreated MCAO-brain, along with remarkable improvement of neurological deficits. Furthermore, the administration of HMGB1 A box/GMS suppressed proinflammatory cytokine inductions more strongly than the injection of non-encapsulated HMGB1 A box. Given that insulted brains-like ischemia have enhanced gelatinase activity than the normal brain, our results suggest that GMS-mediated delivery of therapeutic peptides is a promising means to provide efficient neuroprotection in the postischemic brain.