transforming-growth-factor-beta and Infarction--Middle-Cerebral-Artery

Regulatory T cells (Tregs) play a remarkable role in modulating post-ischemic neuroinflammation. However, the characteristics of Tregs in diabetic ischemic stroke remain unknown.. Transient middle cerebral artery occlusion (MCAO) was conducted on leptin receptor-mutated db/db mice and db/+ mice. The number, cytokine production, and signaling features of Tregs in peripheral blood and ipsilateral hemispheres were evaluated by flow cytometry. Treg plasticity was assessed by the adoptive transfer of splenic Tregs into mice. The effect of ipsilateral macrophages/microglia on Treg plasticity was determined by. db/db mice had more infiltrating Tregs in their ipsilateral hemispheres than db/+ mice. Infiltrating Tregs in db/db mice expressed higher transforming growth factor-β (TGF-β), interleukin-10 (IL-10), forkhead box P3 (Foxp3), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and T-box expressed in T cells (T-bet) in comparison to infiltrating Tregs in db/+ mice, suggesting promoted generation of T helper 1 (Th1)-like Tregs in the brains of db/db mice after stroke. The post-ischemic brain microenvironment of db/db mice significantly up-regulated IFN-γ, TNF-α, T-bet, IL-10, and TGF-β in infiltrating Tregs. Moreover, ipsilateral macrophages/microglia remarkably enhanced the expression of IFN-γ, TNF-α, and T-bet but not IL-10 and TGF-β in Tregs. db/db macrophages/microglia were more potent in up-regulating IFN-γ, TNF-α, and T-bet than db/+ macrophages/microglia. Interleukin-12 (IL-12) blockage partially abolished the modulatory effect of macrophages/microglia on Tregs.. The generation of Th1-like Tregs was promoted in the brains of type 2 diabetic mice after stroke. Our study reveals significant Treg plasticity in diabetic stroke.

Topics: Animals; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Forkhead Transcription Factors; Infarction, Middle Cerebral Artery; Interferon-gamma; Interleukin-10; Interleukin-12; Mice; Phosphates; STAT1 Transcription Factor; STAT5 Transcription Factor; Stroke; T-Lymphocytes, Regulatory; Transforming Growth Factor beta; Transforming Growth Factors; Tumor Necrosis Factor-alpha

Much efforts have been made to probe the mechanism underlying ischemic stroke (IS). This study was proposed to uncover the role of long non-coding RNA rhabdomyosarcoma 2 related transcript (RMST) in IS through microRNA-221-3p (miR-221-3p)/phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1)/transforming growth factor-β (TGF-β) axis. Neurological behavioral function, pathological changes in brain tissue, oxidative stress, and inflammation responses in middle cerebral artery occlusion (MCAO) mice were tested. RMST, miR-221-3p, PIK3R1, and TGF-β signaling-related protein expression in brain tissues of MCAO mice were detected. RMST and PIK3R1 were elevated, miR-221-3p was downregulated, and TGF-β pathway was activated in mice after MCAO. Restored miR-221-3p or depleted RMST improved neurological behavioral functions, relieved pathological injury in brain tissue, and repressed oxidative stress and inflammation in mice after MCAO. Depleted PIK3R1 or restored miR-221-3p offsets the negative effects of overexpressed RMST on mice with MCAO. The present work highlights that RMST augments IS through reducing miR-221-3p-mediated regulation of PIK3R1 and activating TGF-β pathway.

Topics: Animals; Apoptosis; Class Ia Phosphatidylinositol 3-Kinase; Infarction, Middle Cerebral Artery; Inflammation; Ischemic Stroke; Mice; MicroRNAs; RNA, Long Noncoding; Signal Transduction; Stroke; Transforming Growth Factor beta

Some degree of spontaneous recovery is usually observed after stroke. Experimental studies have provided information about molecular mechanisms underlying this recovery. However, the majority of pre-clinical stroke studies are performed in male rodents, and females are not well studied. This is a clear discrepancy when considering the clinical situation. Thus, it is important to include females in the evaluation of recovery mechanisms for future therapeutic strategies. This study aimed to evaluate spontaneous recovery and molecular mechanisms involved in the recovery phase two weeks after stroke in female rats.. Transient middle cerebral artery occlusion was induced in female Wistar rats using a filament model. Neurological functions were assessed up to day 14 after stroke. Protein expression of interleukin 10 (IL-10), transforming growth factor (TGF)-β, neuronal specific nuclei protein (NeuN), nestin, tyrosine-protein kinase receptor Tie-2, extracellular signal-regulated kinase (ERK) 1/2, and Akt were evaluated in the peri-infarct and ischemic core compared to contralateral side of the brain at day 14 by western blot. Expression of TGF-β in middle cerebral arteries was evaluated by immunohistochemistry.. Spontaneous recovery after stroke was observed from day 2 to day 14 and was accompanied by a significantly higher expression of nestin, p-Akt, p-ERK1/2 and TGF-β in ischemic regions compared to contralateral side at day 14. In addition, a significantly higher expression of TGF-β was observed in occluded versus non-occluded middle cerebral arteries. The expression of Tie-2 and IL-10 did not differ between the ischemic and contralateral sides.. Spontaneous recovery after ischemic stroke in female rats was coincided by a difference observed in the expression of molecular markers. The alteration of these markers might be of importance to address future therapeutic strategies.

Topics: Animals; Brain Ischemia; Female; Infarction, Middle Cerebral Artery; Interleukin-10; Ischemic Stroke; Male; Nestin; Pregnancy; Proto-Oncogene Proteins c-akt; Rats; Rats, Wistar; Recovery of Function; Stroke; Transforming Growth Factor beta

The occurrence of ischemia-reperfusion (I/R) injury leads to dysfunction as well as high rates of morbidity and mortality in stroke, and new effective therapeutic strategies for I/R are still needed. We investigated the effect of IL-27 on I/R injury-induced neurological function impairment, cerebral infarction volume and variation in levels of inflammatory factors in mice with middle cerebral artery occlusion (MCAO), as well as concentration of LDH and neuronal apoptosis in a neuron oxygen-glucose deprivation and reperfusion (OGD/R) model mediated by gp130/STAT3 signaling in vitro. Our results indicated that IL-27 could bind to its receptor of gp130 to attenuate the I/R injury-induced impairment function and cerebral infarction volume, and decrease inflammatory cytokines TNF-α, IL-1β and MCP-1 but increase anti-inflammatory factors IL-10 and TGF-β in vivo, while inhibiting LDH leakage and neuronal apoptosis through activation of STAT3 to antagonize I/R induction. Our results suggest that IL-27 may protect the brain from I/R injury through the gp130/STAT3 signaling pathway.

Topics: Animals; Apoptosis; Brain; Cells, Cultured; Chemokine CCL2; Cytokine Receptor gp130; Infarction, Middle Cerebral Artery; Interleukin-10; Interleukin-27; Male; Mice; Mice, Inbred C57BL; Neurons; Neuroprotective Agents; Signal Transduction; STAT3 Transcription Factor; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Topics: Acetylcholinesterase; Animals; Brain; Calcium Channel Blockers; Diabetes Mellitus, Experimental; Dihydropyridines; Infarction, Middle Cerebral Artery; Male; Malondialdehyde; Neuroprotective Agents; Nitrites; Nitrophenols; Organophosphorus Compounds; Oxidative Stress; Rats; Rats, Sprague-Dawley; Signal Transduction; Smad2 Protein; Transforming Growth Factor beta; Vascular Endothelial Growth Factor A

While it has been shown that different T-cell subsets have a detrimental role in the acute phase of ischemic stroke, data on the impact of dendritic cells (DC) are missing. Classic DC can be characterized by the cluster of differentiation (CD)11c surface antigen.. In this study, we depleted CD11c+ cells by using a CD11c-diphtheria toxin (DTX) receptor mouse strain that allows selective depletion of CD11c+ cells by DTX injection. For stroke induction, we used the model of transient middle cerebral artery occlusion (tMCAO) and analyzed stroke volume and functional outcome on days 1 and 3 as well as expression of prototypical pro- and anti-inflammatory cytokines on day 1 after tMCAO. Three different protocols for CD11c+ cell depletion, tMCAO duration, and readout time point were applied.. Injection of DTX (5 or 100 ng/g) reliably depleted CD11c+ cells without influencing the fractions of other immune cell subsets. CD11c+ cell depletion had no impact on stroke volume, but mice with a longer DTX pretreatment performed worse than those with vehicle treatment. CD11c+ cell depletion led to a decrease in cortical interleukin (IL)-1β and IL-6 messenger ribonucleic acid levels.. We show, for the first time, that CD11c+ cell depletion does not influence stroke volume in a mouse model of focal cerebral ischemia. Nevertheless, given the unspecificity of the CD11c surface antigen for DC, mouse models that allow a more selective depletion of DC are needed to investigate the role of DC in stroke pathophysiology.

Topics: Animals; CD11c Antigen; Dendritic Cells; Diphtheria Toxin; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Flow Cytometry; Gene Expression Regulation; Green Fluorescent Proteins; Heparin-binding EGF-like Growth Factor; Infarction, Middle Cerebral Artery; Interleukin-1beta; Male; Mice; Mice, Transgenic; RNA, Messenger; Time Factors; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Cardiovascular diseases are approximately three times higher in patients with neurological deficits than in patients without neurological deficits. MicroRNA-126 (MiR-126) facilitates vascular remodeling and decreases fibrosis and is emerging as an important factor in the pathogenesis of cardiovascular diseases and cerebral stroke. In this study, we tested the hypothesis that decreased miR-126 after ischemic stroke may play an important role in regulating cardiac function. Wild-type (WT), specific conditional-knockout endothelial cell miR-126 (miR-126

Topics: Actins; Animals; Animals, Newborn; Brain; Cells, Cultured; Chemokine CCL2; Disease Models, Animal; Endothelial Cells; Gene Expression Regulation; Heart Diseases; Infarction, Middle Cerebral Artery; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; MicroRNAs; Myocardium; Myocytes, Cardiac; NADPH Oxidase 2; Transforming Growth Factor beta; Vascular Cell Adhesion Molecule-1

Stroke is a leading cause of disability and currently lacks effective therapy enabling long-term functional recovery. Ischemic brain injury causes local inflammation, which involves both activated resident microglia and infiltrating immune cells, including monocytes. Monocyte-derived macrophages (MDMs) exhibit a high degree of functional plasticity. Here, we determined the role of MDMs in long-term spontaneous functional recovery after middle cerebral artery occlusion in mice. Analyses by flow cytometry and immunocytochemistry revealed that monocytes home to the stroke-injured hemisphere., and that infiltration peaks 3 d after stroke. At day 7, half of the infiltrating MDMs exhibited a bias toward a proinflammatory phenotype and the other half toward an anti-inflammatory phenotype, but during the subsequent 2 weeks, MDMs with an anti-inflammatory phenotype dominated. Blocking monocyte recruitment using the anti-CCR2 antibody MC-21 during the first week after stroke abolished long-term behavioral recovery, as determined in corridor and staircase tests, and drastically decreased tissue expression of anti-inflammatory genes, including TGFβ, CD163, and Ym1. Our results show that spontaneously recruited monocytes to the injured brain early after the insult contribute to long-term functional recovery after stroke.. For decades, any involvement of circulating immune cells in CNS repair was completely denied. Only over the past few years has involvement of monocyte-derived macrophages (MDMs) in CNS repair received appreciation. We show here, for the first time, that MDMs recruited to the injured brain early after ischemic stroke contribute to long-term spontaneous functional recovery through inflammation-resolving activity. Our data raise the possibility that inadequate recruitment of MDMs to the brain after stroke underlies the incomplete functional recovery seen in patients and that boosting homing of MDMs with an anti-inflammatory bias to the injured brain tissue may be a new therapeutic approach to promote long-term improvement after stroke.

Topics: Animals; Antibodies, Blocking; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Behavior, Animal; beta-N-Acetylhexosaminidases; Chimera; Functional Laterality; Infarction, Middle Cerebral Artery; Inflammation; Lectins; Macrophages; Male; Mice; Mice, Inbred C57BL; Monocytes; Neuronal Plasticity; Psychomotor Performance; Receptors, CCR2; Receptors, Cell Surface; Recovery of Function; Stroke; Transforming Growth Factor beta

Astrocytes limit inflammation after CNS injury, at least partially by physically containing it within an astrocytic scar at the injury border. We report here that astrocytic transforming growth factor-beta (TGFβ) signaling is a second, distinct mechanism that astrocytes utilize to limit neuroinflammation. TGFβs are anti-inflammatory and neuroprotective cytokines that are upregulated subacutely after stroke, during a clinically accessible time window. We have previously demonstrated that TGFβs signal to astrocytes, neurons and microglia in the stroke border days after stroke. To investigate whether TGFβ affects astrocyte immunoregulatory functions, we engineered "Ast-Tbr2DN" mice where TGFβ signaling is inhibited specifically in astrocytes. Despite having a similar infarct size to wildtype controls, Ast-Tbr2DN mice exhibited significantly more neuroinflammation during the subacute period after distal middle cerebral occlusion (dMCAO) stroke. The peri-infarct cortex of Ast-Tbr2DN mice contained over 60% more activated CD11b(+) monocytic cells and twice as much immunostaining for the activated microglia and macrophage marker CD68 than controls. Astrocytic scarring was not altered in Ast-Tbr2DN mice. However, Ast-Tbr2DN mice were unable to upregulate TGF-β1 and its activator thrombospondin-1 2 days after dMCAO. As a result, the normal upregulation of peri-infarct TGFβ signaling was blunted in Ast-Tbr2DN mice. In this setting of lower TGFβ signaling and excessive neuroinflammation, we observed worse motor outcomes and late infarct expansion after photothrombotic motor cortex stroke. Taken together, these data demonstrate that TGFβ signaling is a molecular mechanism by which astrocytes limit neuroinflammation, activate TGFβ in the peri-infarct cortex and preserve brain function during the subacute period after stroke.

Topics: Animals; Astrocytes; CD11b Antigen; Cerebral Cortex; Disease Models, Animal; Female; Infarction, Middle Cerebral Artery; Macrophages; Mice, Transgenic; Microglia; Monocytes; Motor Activity; Neuroimmunomodulation; Signal Transduction; Stroke; Thrombospondin 1; Transforming Growth Factor beta; Transforming Growth Factor beta1

Transplantation of mesenchymal stem cells (MSCs) has been shown to enhance the recovery of brain functions following ischemic injury. Although immune modulation has been suggested to be one of the mechanisms, the molecular mechanisms underlying improved recovery has not been clearly identified. Here, we report that MSCs secrete transforming growth factor-beta (TGF-β) to suppress immune propagation in the ischemic rat brain. Ischemic stroke caused global death of resident cells in the infarcted area, elevated the monocyte chemoattractant protein-1 (MCP-1) level, and evoked massive infiltration of circulating CD68+ immune cells through the impaired blood-brain barrier. Transplantation of MSCs at day 3 post-ischemia blocked the subsequent upregulation of MCP-1 in the ischemic area and the infiltration of additional CD68+ immune cells. MSC-conditioned media decreased the migration and MCP-1 production of freshly isolated immune cells in vitro, and this effect was blocked by an inhibitor of TGF-β signaling or an anti-TGF-β neutralizing antibody. Finally, transplantation of TGF-β1-silenced MSCs failed to attenuate the infiltration of CD68+ cells into the ischemic brain, and was associated with only minor improvements in motor function. These results indicate that TGF-β is key to the ability of MSCs to beneficially attenuate immune reactions in the ischemic brain. Our findings offer insight into the interactions between allogeneic MSCs and the host immune system, reinforcing the prospective clinical value of using MSCs in the treatment of neurological disorders involving inflammation-mediated secondary damage.

Topics: Animals; Antigens, CD; Blood-Brain Barrier; Brain Infarction; Calcium-Binding Proteins; Cell Movement; Cells, Cultured; Chemokine CCL2; Disease Models, Animal; Encephalitis; Gene Expression Regulation; Infarction, Middle Cerebral Artery; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Microfilament Proteins; Peroxidase; Rats; Rats, Sprague-Dawley; Time Factors; Transforming Growth Factor beta

Transforming growth factor-βs (TGF-β1-3) are cytokines that regulate the proliferation, differentiation, and survival of various cell types. The present study describes the induction of TGF-β1-3 in the rat after focal ischemia at 3 h, 24 h, 72 h and 1 month after transient (1 h) or permanent (24 h) middle cerebral artery occlusion (MCAO) using in situ hybridization histochemistry and quantitative analysis. Double labeling with different markers was used to identify the localization of TGF-β mRNA relative to the penumbra and glial scar, and the types of cells expressing TGF-βs. TGF-β1 expression increased 3 h after MCAO in the penumbra and was further elevated 24 h after MCAO. TGF-β1 was present mostly in microglial cells but also in some astrocytes. By 72 h and 1 month after the occlusion, TGF-β1 mRNA-expressing cells also appeared in microglia within the ischemic core and in the glial scar. In contrast, TGF-β2 mRNA level was increased in neurons but not in astrocytes or microglial cells in layers II, III, and V of the ipsilateral cerebral cortex 24 h after MCAO. TGF-β3 was not induced in cells around the penumbra. Its expression increased in only a few cells in layer II of the cerebral cortex 24 h after MCAO. The levels of TGF-β2 and -β3 decreased at subsequent time points. Permanent MCAO further elevated the levels of all 3 subtypes of TGF-βs suggesting that reperfusion is not a major factor in their induction. TGF-β1 did not co-localize with either Fos or ATF-3, while the co-localization of TGF-β2 with Fos but not with ATF-3 suggests that cortical spreading depolarization, but not damage to neural processes, might be the mechanism of induction for TGF-β2. The results imply that endogenous TGF-βs are induced by different mechanisms following an ischemic attack in the brain suggesting that they are involved in distinct spatially and temporally regulated inflammatory and neuroprotective processes.

Topics: Animals; Brain; Immunohistochemistry; In Situ Hybridization; Infarction, Middle Cerebral Artery; Male; Rats; Rats, Wistar; Transforming Growth Factor beta; Transforming Growth Factor beta1; Transforming Growth Factor beta2; Transforming Growth Factor beta3

Recent studies have shown that administration of granulocyte colony-stimulating factor (G-CSF) is neuroprotective. However, the precise mechanisms of the neuroprotective effect of G-CSF are not entirely known. We carried out 90-min transient middle cerebral occlusion (tMCAO) of rats. The rats were injected with vehicle or G-CSF (50 mug/kg) immediately after reperfusion and sacrificed 8, 24, or 72 hr later. 2,3,5-Triphenyltetrazolium chloride (TTC) staining was carried out using brain sections of 72 hr, and immunohistochemistry was carried out with those of 8, 24, and 72 hr. TTC-staining showed a significant reduction of infarct volume in the G-CSF-treated group (**P < 0.01). Immunohistochemistry showed a significant decrease of the number of cells expressing tumor necrosis factor-alpha (TNF-alpha) at 8-72 hr, transforming growth factor-beta (TGF-beta) and inducible nitric oxide synthase (iNOS) at 24 and 72 hr after tMCAO in the peri-ischemic area (*P < 0.05 each). Our data suggest that the suppression of inflammatory cytokines and iNOS expression may be one mechanism of neuroprotection by G-CSF.

Topics: Animals; Anti-Inflammatory Agents; Brain; Brain Ischemia; Granulocyte Colony-Stimulating Factor; Immunohistochemistry; Infarction, Middle Cerebral Artery; Inflammation; Male; Nervous System; Neuroprotective Agents; Nitric Oxide Synthase Type II; Rats; Rats, Wistar; Stroke; Time Factors; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Bone morphogenetic proteins play a key role in astrocytic differentiation. Astrocytes express the gap junctional protein connexin-43, which permits exchange of small molecules in brain and enhances synaptic efficacy. Bone marrow stromal cells produce soluble factors including bone morphogenetic protein 2 and bone morphogenetic protein 4 (bone morphogenetic protein 2/4) in ischemic brain. Here, we tested whether intra-carotid infusion of bone marrow stromal cells promotes synaptophysin expression and neurological functional recovery after stroke in rats. Adult male Wistar rats were subjected to 2 h of right middle cerebral artery occlusion. Rats were treated with or without bone marrow stromal cells at 24 h after middle cerebral artery occlusion via intra-arterial injection (n=8/group). A battery of functional tests was performed. Immunostaining of 5-bromo-2-deoxyuridine, Ki67, bone morphogenetic protein 2/4, connexin-43, synaptophysin, glial fibrillary acidic protein, neuronal nuclear antigen, and double staining of 5-bromo-2-deoxyuridine/glial fibrillary acidic protein, 5-bromo-2-deoxyuridine/neuronal nuclear antigen, glial fibrillary acidic protein/bone morphogenetic protein 2/4 and glial fibrillary acidic protein/connexin-43 were employed. Rats treated with bone marrow stromal cells significantly (P<0.05) improved functional recovery compared with the controls. 5-Bromo-2-deoxyuridine and Ki67 positive cells in the ipsilateral subventricular zone were significantly (P<0.05) increased in bone marrow stromal cell treatment group compared with the controls, respectively. Administration of bone marrow stromal cells significantly (P<0.05) promoted the proliferating cell astrocytic differentiation, and increased bone morphogenetic protein 2/4, connexin-43 and synaptophysin expression in the ischemic boundary zone compared with the controls, respectively. Bone morphogenetic protein 2/4 expression correlated with the expression of connexin-43 (r=0.84, P<0.05) and connexin-43 expression correlated with the expression of synaptophysin (r=0.73, P<0.05) in the ischemic boundary zone, respectively. Administration of bone marrow stromal cells via an intra-carotid route increases endogenous brain bone morphogenetic protein 2/4 and connexin-43 expression in astrocytes and promotes synaptophysin expression, which may benefit functional recovery after stroke in rats.

Topics: Analysis of Variance; Animals; Body Weight; Bone Marrow Cells; Bone Marrow Transplantation; Bone Morphogenetic Protein 2; Bone Morphogenetic Protein 4; Bone Morphogenetic Proteins; Bromodeoxyuridine; Cell Differentiation; Connexin 43; Glial Fibrillary Acidic Protein; Immunohistochemistry; Infarction, Middle Cerebral Artery; Injections, Intra-Arterial; Ki-67 Antigen; Male; Phosphopyruvate Hydratase; Rats; Rats, Wistar; Stromal Cells; Synaptophysin; Transforming Growth Factor beta; Up-Regulation

The transcription factor NF-kappaB is a key regulator of inflammation and cell survival. NF-kappaB is activated by cerebral ischemia in neurons and glia, but its function is controversial. To inhibit NF-kappaB selectively in neurons and glial cells, we have generated transgenic mice that express the IkappaBalpha superrepressor (IkappaBalpha mutated at serine-32 and serine-36, IkappaBalpha-SR) under transcriptional control of the neuron-specific enolase (NSE) and the glial fibrillary acidic protein (GFAP) promoter, respectively. In primary cortical neurons of NSE-IkappaBalpha-SR mice, NF-kappaB activity was partially inhibited. To assess NF-kappaB activity in vivo after permanent middle cerebral artery occlusion (MCAO), we measured the expression of NF-kappaB target genes by real-time polymerase chain reaction (PCR). The induction of c-myc and transforming growth factor-beta2 by cerebral ischemia was inhibited by neuronal expression of IkappaBalpha-SR, whereas induction of GFAP by MCAO was reduced by astrocytic expression of IkappaBalpha-SR. Neuronal, but not astrocytic, expression of the NF-kappaB inhibitor reduced both infarct size and cell death 48 hours after permanent MCAO. In summary, the data show that NF-kappaB is activated in neurons and astrocytes during cerebral ischemia and that NF-kappaB activation in neurons contributes to the ischemic damage.

Topics: Amino Acid Substitution; Animals; Astrocytes; Brain Ischemia; Cell Death; Gene Expression Regulation; Glial Fibrillary Acidic Protein; I-kappa B Proteins; Infarction, Middle Cerebral Artery; Mice; Mice, Transgenic; Neurons; NF-kappa B; NF-KappaB Inhibitor alpha; Phosphopyruvate Hydratase; Point Mutation; Promoter Regions, Genetic; Proto-Oncogene Proteins c-myc; Transcription Factor RelA; Transforming Growth Factor beta

Gender differences in outcome following cerebral ischemia have frequently been observed and attributed to the actions of steroid hormones. Progesterone has been shown to possess neuroprotective properties following transient ischemia, with respect to decreasing lesion volume and improving functional recovery. The present study was designed to determine the mechanisms of progesterone neuroprotection, and whether these relate to the inflammatory response. Male mice underwent either 60 min or permanent middle cerebral artery occlusion (MCAO) and received progesterone (8 mg/kg ip) or vehicle 1 h, 6 h and 24 h post-MCAO. Forty-eight hours following transient MCAO, structural magnetic resonance imaging revealed a significant decrease in the amount of edematous tissue present in progesterone-treated mice as compared with vehicle. Using real-time PCR we found that progesterone treatment significantly suppressed the injury-induced upregulation of interleukin (IL)-1beta, transforming growth factor (TGF)beta2, and nitric oxide synthase (NOS)-2 mRNAs in the ipsilateral hemisphere while having no effect on tumor necrosis factor (TNF)-alpha mRNA expression. Progesterone treatment following permanent MCAO also resulted in a significant decrease in lesion volume. This was not apparent in mice lacking a functional NOS-2 gene. Thus, progesterone is neuroprotective in both permanent and transient ischemia, and this effect is related to the suppression of specific aspects of the inflammatory response.

Topics: Animals; Brain; Brain Ischemia; Disease Models, Animal; Infarction, Middle Cerebral Artery; Inflammation; Interleukin-1; Magnetic Resonance Imaging; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Progesterone; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Tetrazolium Salts; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

We monitored alterations in cerebral blood flow (CBF) and blood-brain barrier (BBB) permeability following middle cerebral artery occlusion (MCAo) and intrastriatal transplantation of mouse bone marrow stromal cells (BMSCs) or saline infusion in adult Sprague-Dawley rats. Laser Doppler and Evans Blue assay revealed that BMSC grafts dose-dependently restored CBF and BBB to near normal levels at a much earlier period (Days 4-5 post-MCAo) in transplanted stroke animals compared to stroke animals that received saline infusion (Days 11-14 post-MCAo). Xenografted BMSCs survived in the absence of immunosuppression, and elevated levels of transforming growth factor-beta superfamily of neurotrophic factors were detected in transplanted stroke animals. These data suggest that early restoration of CBF and BBB following transplantation of BMSCs could mediate the reported functional outcomes in stroke animals.

Topics: Animals; Blood-Brain Barrier; Bone Marrow Transplantation; Cerebrovascular Circulation; Corpus Striatum; Disease Models, Animal; Graft Survival; Immunosuppressive Agents; Infarction, Middle Cerebral Artery; Male; Rats; Rats, Sprague-Dawley; Recovery of Function; Stroke; Stromal Cells; Transforming Growth Factor beta; Treatment Outcome; Up-Regulation

We and others have previously reported that bone morphogenetic protein-7 (BMP-7), given before middle cerebral artery occlusion (MCAO), reduces ischemic injury in brain. Recent studies have indicated that receptors for BMP are upregulated after brain ischemia. It is possible that this upregulation may facilitate endogenous neurorepair in the ischemic brain. The purpose of this study was to determine the neuroregenerative effects of BMP-7 given parenterally after ischemia/reperfusion injury.. Adult Sprague-Dawley rats were anesthetized with chloral hydrate. The middle cerebral artery was transiently occluded by a filament inserted through the right internal carotid artery. The filament was removed after 60-minute ischemia to allow reperfusion. Some animals were killed 24 hours after MCAO to examine BMP-7 mRNA expression. Other animals received a single dose of intravenous BMP-7 or vehicle at 24 hours after MCAO and were used for subsequent behavioral studies and BMP-7 immunostaining.. BMP-7 mRNA was upregulated 24 hours after MCAO in untreated animals. BMP-7 immunoreactivity was dose-dependently increased on the ischemic side of the hippocampus/dentate on day 6 after MCAO in animals receiving intravenous injection of BMP-7. Animals receiving BMP-7 also showed a decrease in body asymmetry from day 7 to day 14 and an increase in locomotor activity on day 14 after MCAO.. Our data indicate that BMP-7, given parenterally after stroke, can pass through the blood-brain barrier on the ischemic side and induce behavioral recovery in stroke animals at longer testing times.

Topics: Animals; Behavior, Animal; Bone Morphogenetic Protein 7; Bone Morphogenetic Proteins; Brain; Disease Models, Animal; Dose-Response Relationship, Drug; Immunohistochemistry; Infarction, Middle Cerebral Artery; Injections, Intravenous; Ischemic Attack, Transient; Male; Motor Activity; Rats; Rats, Sprague-Dawley; Recovery of Function; Reperfusion Injury; RNA, Messenger; Stroke; Survival Rate; Transforming Growth Factor beta

Despite the characterization of neuroprotection by transforming growth factor-beta1 (TGF-beta1), the signaling pathway mediating its protective effect is unclear. Bad is a proapoptotic member of the Bcl-2 family and is inactivated on phosphorylation via mitogen-activated protein kinase (MAPK). This study attempted to address whether MAPK signaling and Bad phosphorylation were influenced by TGF-beta1 and, furthermore, whether these two events were involved in the antiapoptotic effect of TGF-beta1. We found a gradual activation of extracellular signal-regulated kinase 1/2 (Erk1/2) and MAPK-activated protein kinase-1 (also called Rsk1) and a concomitant increase in Bad phosphorylation at Ser(112) in mouse brains after adenovirus-mediated TGF-beta1 transduction under nonischemic and ischemic conditions induced by transient middle cerebral artery occlusion. Consistent with these effects, the ischemia-induced increase in Bad protein level and caspase-3 activation were suppressed in TGF-beta1-transduced brain. Consequently, DNA fragmentation, ischemic lesions, and neurological deficiency were significantly reduced. In cultured rat hippocampal cells, TGF-beta1 inhibited the increase in Bad expression caused by staurosporine. TGF-beta1 concentration- and time-dependently activated Erk1/2 and Rsk1 accompanied by an increase in Bad phosphorylation. These effects were blocked by U0126, a mitogen-activated protein kinase/Erk kinase 1/2 inhibitor, suggesting an association between Bad phosphorylation and MAPK activation. Notably, U0126 and a Rsk1 inhibitor (Ro318220) abolished the neuroprotective activity of TGF-beta1 in staurosporine-induced apoptosis, indicating that activation of MAPK is necessary for the antiapoptotic effect of TGF-beta1 in cultured hippocampal cells. Together, we demonstrate that TGF-beta1 suppresses Bad expression under lesion conditions, increases Bad phosphorylation, and activates the MAPK/Erk pathway, which may contribute to its neuroprotective activity.

Topics: Animals; Apoptosis; bcl-Associated Death Protein; Carrier Proteins; Caspase 3; Caspases; Cells, Cultured; Enzyme Activation; Enzyme Inhibitors; Gene Expression; Hippocampus; Infarction, Middle Cerebral Artery; Ischemic Attack, Transient; Male; Mice; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Mitogen-Activated Protein Kinases; Neurons; Neuroprotective Agents; Phosphorylation; Ribosomal Protein S6 Kinases; Ribosomal Protein S6 Kinases, 90-kDa; Signal Transduction; Transduction, Genetic; Transforming Growth Factor beta; Transforming Growth Factor beta1

Background and Purpose-Chemokines have been shown to play an important role in leukocyte and monocyte/macrophage infiltration into ischemic regions. The purpose of this study is to identify whether overexpression of the active human transforming growth factor-ss1 (ahTGF-ss1) can downregulate expression of monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1alpha (MIP-1alpha), and intercellular adhesion molecule-1 (ICAM-1) and reduce ischemic brain injury.. -Overexpression of transforming growth factor-ss1 (TGF-ss1) was achieved through adenoviral gene transfer. Five days after adenoviral transduction, the mouse underwent 30 minutes of middle cerebral artery occlusion followed by 1 to 7 days of reperfusion. TGF-ss1, MCP-1, MIP-1alpha, and ICAM-1 were detected by enzyme-linked immunosorbent assay and immunohistochemistry. Infarct areas and volumes were measured by cresyl violet staining.. -MCP-1 and MIP-1alpha expression is increased after middle cerebral artery occlusion, and double-labeled immunostaining revealed that MCP-1 is colocalized with neurons and astrocytes. Viral-mediated TGF-ss1 overexpression was significantly greater at measured time points, with a peak at 7 to 9 days. The expression of MCP-1 and MIP-1alpha, but not ICAM-1, was reduced in the mice overexpressing ahTGF-ss1 (P:<0.05). Furthermore, infarct volume was significantly reduced in the mice overexpressing ahTGF-ss1 (P:<0.05).. -This study demonstrates that MCP-1 and MIP-1alpha expressed in the ischemic region may play an important role in attracting inflammatory cells. The reduction of MCP-1 and MIP-1alpha, but not ICAM-1, in the mice overexpressing ahTGF-ss1 suggests that the neuroprotective effect of TGF-ss1 may result from the inhibition of chemokines during cerebral ischemia and reperfusion.

Topics: Adenoviridae; Animals; Blood Flow Velocity; Brain; Brain Ischemia; Chemokine CCL2; Chemokine CCL3; Chemokine CCL4; Disease Models, Animal; Gene Transfer Techniques; Genetic Vectors; Humans; Immunohistochemistry; Infarction, Middle Cerebral Artery; Inflammation; Intercellular Adhesion Molecule-1; Macrophage Inflammatory Proteins; Mice; Reperfusion; Transforming Growth Factor beta; Transforming Growth Factor beta1

Bone morphogenetic protein-7 (BMP-7) has been shown to enhance dendritic growth and improve functional recovery after experimental stroke. In this study, we examined the effect of BMP-7 on functional recovery, local cerebral blood flow (LCBF) and local cerebral glucose utilization (LCMRglu) following transient middle cerebral artery occlusion. Sprague--Dawley rats (n=29) were anesthetized with halothane/nitrous oxide and received 2-h middle cerebral artery occlusion (MCAo) by poly-L-lysine-coated intraluminal suture. Rectal and cranial temperatures were regulated at 37.0--37.5 degrees C. BMP-7 or vehicle (volume, 25 microl) was administered intracisternally in a blinded fashion at 24 h after MCAo. Neurological status was evaluated during occlusion (60 min) and daily for 2 days after MCAo. In matched animal groups, LCMRglu was measured autoradiographically with [(14)C]2-deoxyglucose (2-DG) and LCBF with [(14)C]iodoantipyrine 48 h after MCAo. Four animals groups were studied: LCMRglu series (BMP-7, n=7; vehicle, n=8); LCBF series (BMP-7, n=6; vehicle, n=8). Average three-dimensional image data sets were constructed for each group and were compared by pixel-based statistical methods. Rectal and cranial temperatures, mean blood pressure, plasma glucose and blood gases were similar among groups. BMP-7 significantly improved the total neurological score compared to vehicle at 48 h after MCAo (7.3+/-0.4 vs. 9.0+/-0.2, respectively; P<0.0003). Compared to vehicle-rats, BMP-7 enhanced glucose utilization in the basal ganglia ipsilateral to stroke and improved LCBF in ipsilateral subthalamus, but decreased LCBF and LCMRglu in contralateral cortical regions.

Topics: Animals; Blood Pressure; Body Temperature; Bone Morphogenetic Protein 7; Bone Morphogenetic Proteins; Brain; Brain Ischemia; Cerebrovascular Circulation; Glucose; Infarction, Middle Cerebral Artery; Male; Movement Disorders; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Recovery of Function; Transforming Growth Factor beta

We have reviewed a battery of useful tests for evaluating sensorimotor function and plasticity acutely and chronically in unilateral rat models of central nervous system injury. These tests include forelimb use for weight shifting during vertical exploration in a cylindrical enclosure, an adhesive removal test of sensory function, and forelimb placing. These tests monitor recovery of sensorimotor function independent of the extent of test experience. Data are presented for four models, including permanent focal ischemia, focal injury to the forelimb area of sensorimotor cortex, dopaminergic neurodegeneration of the nigrostriatal system, and cervical spinal cord injury. The effect of the dendrite growth promoting factor, Osteogenic Protein-1 (OP-1) on outcome following permanent middle cerebral artery (MCA) occlusion was used as an example to illustrate how the tests can be applied preclinically. OP-1 showed a beneficial effect on limb use asymmetry in the cylinder test.

Topics: Animals; Behavior, Animal; Bone Morphogenetic Protein 7; Bone Morphogenetic Proteins; Brain Ischemia; Cerebral Decortication; Cervical Vertebrae; Dendrites; Disease Models, Animal; Evaluation Studies as Topic; Forelimb; Functional Laterality; Infarction, Middle Cerebral Artery; Male; Neck; Neuronal Plasticity; Neuropsychological Tests; Oxidopamine; Parkinsonian Disorders; Rats; Rats, Sprague-Dawley; Recovery of Function; Somatosensory Cortex; Spinal Cord Injuries; Stroke; Transforming Growth Factor beta

Osteogenic protein-1 (OP-1, BMP-7) is a member of the bone morphogenetic protein subfamily of the TGF-ss superfamily that selectively stimulates dendritic neuronal outgrowth. In previous studies, we found that the intracisternal injection of OP-1, starting at one day after stroke, enhanced sensorimotor recovery of the contralateral limbs following unilateral cerebral infarction in rats. In the current study, we further explored the time window during which intracisternal OP-1 enhances sensorimotor recovery, as assessed by limb placing tests. We found that intracisternal OP-1 (10 microg) given 1 and 3 days, or 3 and 5 days, but not 7 and 9 days after stroke, significantly enhanced recovery of forelimb and hindlimb placing. There was no difference in infarct volume between vehicle- and OP-1-treated animals. The mechanism of OP-1 action might be stimulation of new dendritic sprouting in the remaining uninjured brain.

Topics: Animals; Behavior, Animal; Body Weight; Bone Morphogenetic Protein 7; Bone Morphogenetic Proteins; Cerebral Cortex; Corpus Striatum; Forelimb; Hindlimb; Infarction, Middle Cerebral Artery; Injections, Intraventricular; Male; Neuroprotective Agents; Psychomotor Performance; Rats; Rats, Sprague-Dawley; Recovery of Function; Stroke; Time Factors; Transforming Growth Factor beta