transforming-growth-factor-beta and Cerebral-Infarction

Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL) is a single-gene disorder directly affecting the cerebral small blood vessels, that is caused by mutations in the HTRA1 gene encoding HtrA serine peptidase/protease 1 (HTRA1). CARASIL is the second known genetic form of ischemic, nonhypertensive, cerebral small-vessel diseases with an identified gene, following CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy). The exact prevalence of CARASIL is currently unknown, and so far about 50 patients have been reported, most of them from Japan and two from China. Genetically no founder haplotype has been identified, and so the disease is expected to be found more widely. The main clinical manifestations are ischemic stroke or stepwise deterioration in brain functions, progressive dementia, premature baldness, and attacks of severe low back pain or spondylosis deformans/disk herniation. The most characteristic brain MRI findings are homogeneously confluent white-matter changes and multiple lacunar infarctions in the basal ganglia and thalamus. Histopathologically, CARASIL is characterized by intense arteriosclerosis, mainly in the small penetrating arteries, without granular osmiophilic materials (GOM) or amyloid deposition. CARASIL is a prototype single-gene disorder of cerebral small vessels, secondary to and distinct from CADASIL. CARASIL-associated mutant HTRA1s exhibited decreased protease activity and failed to repress transforming growth factor-β (TGF-β) family signaling, indicating that the increased TGF-β signaling causes arteriopathy in CARASIL. Therefore, HTRA1 represents another new gene to be considered in future studies of the mechanisms and therapeutic strategies of cerebral small-vessel diseases, as well as alopecia and degenerative vertebral/disk diseases.

Topics: Adult; Alopecia; Blood Vessels; Brain; Cerebral Infarction; Dementia, Vascular; Genes, Recessive; High-Temperature Requirement A Serine Peptidase 1; Humans; Leukoencephalopathy, Progressive Multifocal; Low Back Pain; Male; Middle Aged; Mutation; Serine Endopeptidases; Spondylosis; Syndrome; Transforming Growth Factor beta

Topics: Adult; Cerebral Infarction; Dementia, Vascular; Female; Genes, Recessive; High-Temperature Requirement A Serine Peptidase 1; Humans; Leukoencephalopathy, Progressive Multifocal; Male; Serine Endopeptidases; Transforming Growth Factor beta

Topics: Cerebral Infarction; Cytokines; Humans; Interleukin-1; Interleukin-10; Interleukin-6; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL) is a life-threatening, inherited, nonhypertensive arteriole disease of the brain. Therapeutic strategy for CARASIL is limited because its pathogenesis is not clear. We previously reported the first family with CARASIL in China, which involves a high-temperature requirement serine protease gene mutation (HtrA1. Food maze and water maze experiments were used in the behavioral studies. Pathological studies were carried out by arteriole labeling staining and electron microscopy. The mRNA and protein expression levels of the key factors of TGF-β/Smad signaling pathway (TGF-β, Smad2, Smad3, and Smad4) in the brain of the model mice were detected by immunohistochemistry, real-time quantitative polymerase chain reaction (RT-PCR), and Western blot assay.. The food maze and water maze experiment data showed significant differences between the Mut and wild-type (WT) mice in the first time to find food, the time to contact the escape table for the first time, and the number of times to travel in the escape table quadrant (p < 0.001). The results of vascular labeling staining showed that some small arteries in the brain of Mut mice lost normal structure. The results of electron microscopy showed that the cell morphologies in the cortex and hippocampus of Mut mice were abnormal; the number of synapses was reduced; the walls of capillaries, venules, and arterioles thickened; lumen stenosis and other abnormal phenomenon occurred; and lipofuscin deposition and autophagosomes were found in the hippocampus. Immunohistochemistry, RT-PCR, and Western Blot results showed that the mRNA and protein expression levels of TGF-β, Smad2, and Smad3 in the brain of Mut mice increased to different degrees.. The most significant innovation of this study is the first study on the pathogenesis of CARASIL disease using model animals. The Mut mice can well simulate the pathogenesis of CARASIL in behavioral and pathological aspects. The TGF-β/Smad signaling pathway, which is involved in the pathogenesis of CARASIL, is abnormally upregulated in the brain of Mut mice.

Topics: Alopecia; Animals; Cerebral Arterial Diseases; Cerebral Infarction; Cerebrovascular Disorders; Cognitive Dysfunction; High-Temperature Requirement A Serine Peptidase 1; Leukoencephalopathies; Mice; RNA, Messenger; Signal Transduction; Spinal Diseases; Transforming Growth Factor beta

Cerebral small vessel disease (CSVD) causes dementia and gait disturbance due to arteriopathy. Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL) is a hereditary form of CSVD caused by loss of high-temperature requirement A1 (HTRA1) serine protease activity. In CARASIL, arteriopathy causes intimal thickening, smooth muscle cell (SMC) degeneration, elastic lamina splitting, and vasodilation. The molecular mechanisms were proposed to involve the accumulation of matrisome proteins as substrates or abnormalities in transforming growth factor β (TGF-β) signaling. Here, we show that HTRA1-/- mice exhibited features of CARASIL-associated arteriopathy: intimal thickening, abnormal elastic lamina, and vasodilation. In addition, the mice exhibited reduced distensibility of the cerebral arteries and blood flow in the cerebral cortex. In the thickened intima, matrisome proteins, including the hub protein fibronectin (FN) and latent TGF-β binding protein 4 (LTBP-4), which are substrates of HTRA1, accumulated. Candesartan treatment alleviated matrisome protein accumulation and normalized the vascular distensibility and cerebral blood flow. Furthermore, candesartan reduced the mRNA expression of Fn1, Ltbp-4, and Adamtsl2, which are involved in forming the extracellular matrix network. Our results indicate that these accumulated matrisome proteins may be potential therapeutic targets for arteriopathy in CARASIL.

Topics: ADAMTS Proteins; Alopecia; Animals; Benzimidazoles; Biphenyl Compounds; Cerebral Infarction; Cerebrovascular Circulation; Disease Progression; Extracellular Matrix Proteins; High-Temperature Requirement A Serine Peptidase 1; Latent TGF-beta Binding Proteins; Leukoencephalopathies; Mice; Mice, Inbred C57BL; Recombinant Proteins; Spinal Diseases; Tetrazoles; Transforming Growth Factor beta

High temperature requirement A1 (HTRA1) is a serine protease playing a modulatory role in various cell processes, particularly in the regulation of transforming growth factor-β (TGF-β) signaling. A deleterious role in late-onset cerebral small vessel diseases (CSVDs) of heterozygous HTRA1 mutations, otherwise causative in homozygosity of cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy, was recently suggested. However, the pathomechanism of these heterozygous mutations is still undefined. Our aim is to evaluate the expression profile and activity of HTRA1 on TGF-β signaling in fibroblasts from four subjects carrying the HTRA1 heterozygous mutations-p.E42Dfs*173, p.A321T, p.G295R, and p.Q151K. We found a 50% reduction of HTRA1 expression in HTRA1 mutation carriers compared to the control. Moreover, we showed no changes in TGF-β signaling pathway downstream intermediate, Phospho Smad2/3. However, we found overexpression of genes involved in the extracellular matrix formation in two heterozygous HTRA1 carriers. Our results suggest that each heterozygous HTRA1 missense mutation displays a different and peculiar HTRA1 expression pattern and that CSVD phenotype may also result from 50% of HTRA1 expression.

Topics: Alopecia; Cells, Cultured; Cerebral Infarction; Cerebrovascular Disorders; Female; Fibroblasts; Heterozygote; High-Temperature Requirement A Serine Peptidase 1; Humans; Leukoencephalopathies; Male; Middle Aged; Mutation; Signal Transduction; Spinal Diseases; Transcriptome; Transforming Growth Factor beta

Cerebral infarction is an acute cerebrovascular disease caused by abnormal blood circulation in the brain. In the present study, we investigate the effect of astragaloside IV on cognitive dysfunction in cerebrally infarcted rats via transforming growth factor-β (TGF-β) / Smad signaling pathway. For this purpose, 45 rats were divided into three groups including astragaloside, model, and control. 30 of 45 healthy adult male SD rats were randomly selected to establish an acute cerebral infarction model. 15 modeled rats were enrolled as a model and astragaloside group, and another 15 rats as a blank control group. The rats in the astragaloside group were fed with astragaloside IV according to 1.08 g/kg body weight, and those in the blank group and model group were given matching normal saline. The levels of TGF-β, Smad1, Smad3 and Smad7 of TGF-β/Smad signaling transduction pathway at T0 (week 0), T1 (week 3) and T2 (week 6) were determined by enzyme-linked immunosorbent assay (ELISA). The modified neurological severity score (mNSS) was used to evaluate the improvement of cognitive dysfunction in rats. The mNSS of rats with cerebral infarction in the astragaloside group was lower than that in the control group and model group (P< 0.05). While the levels of TGF-β, Smad1, Smad3 and Smad7 in the astragaloside group were higher than those in the control group and model group (P< 0.05). Astragaloside IV plays an important role in improving cognitive dysfunction in rats with cerebral infarction while affecting the levels of TGF-β, Smad1, Smad3 and Smad7 and activating TGF-β / Smad signaling pathway.

Topics: Animals; Case-Control Studies; Cerebral Infarction; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Male; Rats; Rats, Sprague-Dawley; Saponins; Severity of Illness Index; Signal Transduction; Smad Proteins; Smad1 Protein; Smad3 Protein; Smad7 Protein; Transforming Growth Factor beta; Triterpenes

GDF-15 is a novel distant member of the TGF-β superfamily and is widely distributed in the brain and peripheral nervous system. We have previously reported that GDF-15 is a potent neurotrophic factor for lesioned dopaminergic neurons in the substantia nigra, and that GDF-15-deficient mice show progressive postnatal losses of motor and sensory neurons. We have now investigated the regulation of GDF-15 mRNA and immunoreactivity in the murine hippocampal formation and selected cortical areas following an ischemic lesion by occlusion of the middle cerebral artery (MCAO). MCAO prominently upregulates GDF-15 mRNA in the hippocampus and parietal cortex at 3 h and 24 h after lesion. GDF-15 immunoreactivity, which is hardly detectable in the unlesioned brain, is drastically upregulated in neurons identified by double-staining with NeuN. NeuN staining reveals that most, if not all, neurons in the granular layer of the dentate gyrus and pyramidal layers of the cornu ammonis become GDF-15-immunoreactive. Moderate induction of GDF-15 immunoreactivity has been observed in a small number of microglial cells identified by labeling with tomato lectin, whereas astroglial cells remain GDF-15-negative after MCAO. Comparative analysis of the size of the infarcted area after MCAO in GDF-15 wild-type and knockout mice has failed to reveal significant differences. Together, our data substantiate the notion that GDF-15 is prominently upregulated in the lesioned brain and might be involved in orchestrating post-lesional responses other than the trophic support of neurons.

Topics: Animals; Brain Ischemia; Cells, Cultured; Cerebral Cortex; Cerebral Infarction; Gene Expression Regulation; Growth Differentiation Factor 15; Male; Mice; Mice, Inbred C57BL; Middle Cerebral Artery; Models, Animal; Neurons; RNA, Messenger; Transforming Growth Factor beta; Up-Regulation

The genetic cause of cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL), which is characterized by ischemic, nonhypertensive, cerebral small-vessel disease with associated alopecia and spondylosis, is unclear.. In five families with CARASIL, we carried out linkage analysis, fine mapping of the region implicated in the disease, and sequence analysis of a candidate gene. We also conducted functional analysis of wild-type and mutant gene products and measured the signaling by members of the transforming growth factor beta (TGF-beta) family and gene and protein expression in the small arteries in the cerebrum of two patients with CARASIL.. We found linkage of the disease to the 2.4-Mb region on chromosome 10q, which contains the HtrA serine protease 1 (HTRA1) gene. HTRA1 is a serine protease that represses signaling by TGF-beta family members. Sequence analysis revealed two nonsense mutations and two missense mutations in HTRA1. The missense mutations and one of the nonsense mutations resulted in protein products that had comparatively low levels of protease activity and did not repress signaling by the TGF-beta family. The other nonsense mutation resulted in the loss of HTRA1 protein by nonsense-mediated decay of messenger RNA. Immunohistochemical analysis of the cerebral small arteries in affected persons showed increased expression of the extra domain-A region of fibronectin and versican in the thickened tunica intima and of TGF-beta1 in the tunica media.. CARASIL is associated with mutations in the HTRA1 gene. Our findings indicate a link between repressed inhibition of signaling by the TGF-beta family and ischemic cerebral small-vessel disease, alopecia, and spondylosis.

Topics: Adult; Aged, 80 and over; Alopecia; Cerebral Arterial Diseases; Cerebral Arteries; Cerebral Infarction; Female; Genes, Recessive; High-Temperature Requirement A Serine Peptidase 1; Humans; Male; Middle Aged; Mutation; Pedigree; Serine Endopeptidases; Signal Transduction; Spondylosis; Syndrome; Transcription, Genetic; Transforming Growth Factor beta; Tunica Intima

Previous reports have indicated that the expression of bone morphogenetic protein-7 (BMP7) is enhanced after ischemic injury in brain. This upregulation may induce endogenous neurorepair in the ischemic brain. The purpose of this study was to examine neuroregenerative effects of BMP7 after ischemia-reperfusion injury. Adult Sprague-Dawley rats were anesthetized with chloral hydrate. Right middle cerebral artery (MCA) was transiently ligated with 10-O suture for 1 h. One day after MCA occlusion, vehicle or BMP7 was infused to the contralateral cerebral ventricle. To identify possible neurogenesis, bromodeoxyurindine (BrdU) was systemically injected on the fourth and fifth days after MCA occlusion. Animals treated with BMP7 showed a rapid correction of body asymmetry and neurological deficits, suggesting BMP7 facilitates recovery after stroke. Animals were sacrificed at 1 month after stroke and brains were analyzed using immunohistological techniques. BMP7 treatment enhanced immunoreactivity of BrdU in the subventricular zone, lesioned cortex, and corpus callosum. These BrdU-positive cells co-labeled with nestin and NeuN. Our behavioral and anatomical data suggest that BMP7 promotes neuroregeneration in stroke animals, possibly through the proliferation of new neuronal precursors after ischemia.

Topics: Analysis of Variance; Animals; Behavior, Animal; Bone Morphogenetic Protein 7; Bone Morphogenetic Proteins; Bromodeoxyuridine; Cell Count; Cerebral Infarction; Disease Models, Animal; Glial Fibrillary Acidic Protein; Immunohistochemistry; Intermediate Filament Proteins; Male; Nerve Regeneration; Nerve Tissue Proteins; Nestin; Neuroprotective Agents; Phosphopyruvate Hydratase; Rats; Rats, Sprague-Dawley; Recovery of Function; Stroke; Tetrazolium Salts; Time Factors; Transforming Growth Factor beta; Treatment Outcome

Bone morphogenetic proteins (BMPs) affect cell proliferation and differentiation. Astrocytes in ischemic brain are highly responsive to bone marrow stromal cell (BMSC) treatment. We investigated the effects of BMSCs on astrocytes cultured under oxygen- and glucose-deprived conditions, which in part simulate in vivo stroke conditions, to test the hypothesis that BMSCs alter astrocytic expression of BMPs which may contribute to neurological functional recovery of stroke. Quantitative real-time RT-PCR showed that the expression of BMP2/4 mRNAs decreased within ischemic astrocytes, In contrast, BMP2/4 mRNA was significantly increased after cocultured with BMSCs. Western blotting also confirmed this increase at the protein level in the medium of ischemic astrocytes after coculture with BMSCs. As a source of neural stem and progenitor cells, cultured subventricular zone (SVZ) neurospheres exposed to medium obtained from ischemic astrocytes cocultured with BMSCs were significantly enriched in cells expressing the astrocytic marker glial fibrillary acidic protein (GFAP), but not at the expense of beta-III-tubulin-positive SVZ neuroblasts. The expression of BMP2/4 subsequently increased the phosphorylation of downstream effector Smad1 and the expression of notch signal pathway-induced protein Hes1 in cultured SVZ neurospheres. BMP antagonist Noggin blocked the elevation of phosphorylated Smad1 and the expression of Hes1 as well as reducing the percentage of astrocytic SVZ progenitor cells. Our results indicate that BMSCs increase BMP2/4 expression in ischemic astrocytes. These changes enhance subventricular progenitor cell gliogenesis by activating relevant signaling pathways. BMSC-stimulated signaling of endogenous astrocytes may alter the ischemic environment, promoting remodeling of brain and hence, improve functional recovery after stroke.

Topics: Animals; Astrocytes; Basic Helix-Loop-Helix Transcription Factors; Bone Marrow Cells; Bone Morphogenetic Protein 2; Bone Morphogenetic Protein 4; Bone Morphogenetic Proteins; Brain; Brain Ischemia; Cell Communication; Cell Differentiation; Cell Line; Cells, Cultured; Cerebral Infarction; Culture Media, Conditioned; Glial Fibrillary Acidic Protein; Glucose; Homeodomain Proteins; Nerve Regeneration; Oxygen; Phenotype; Rats; Rats, Wistar; RNA, Messenger; Smad1 Protein; Stem Cells; Stromal Cells; Transcription Factor HES-1; Transforming Growth Factor beta

The herbal formulation "Jeo Dang-Tang" (JDT) has long been used for various cerebrovascular diseases. However, very little has scientific investigation been carried out. The aim of the present study is to investigate the effect of JDT on the production of various cytokines in the patients with cerebral infarction (CI). Peripheral blood mononuclear cells (PBMC) obtained from the patients with CI were cultured for 24h in the presence or absence of lipopolysaccharide (LPS) or phytohemagglutinin (PHA). The amount of interleukin (IL)-4, IL-10 and transforming growth factor (TGF)-1beta, in culture supernatant, was significantly increased in the JDT, LPS or PHA treated cells compared to unstimulated cells (P < 0.05). We also show that increased IL-4, and IL-10 level by LPS or PHA was significantly inhibited by JDT in a dose-dependent manner. Maximal inhibition rate of IL-4 and IL-10 production by JDT was 45 +/- 2% and 51 +/- 5% for LPS-stimulated cell and 41.5 +/- 3% and 70.8 +/- 2% for PHA-stimulated cells, respectively (P < 0.05). On the other hand, JDT significantly increased the LPS or PHA-induced TGF-beta1 production (P < 0.05). These data suggest that JDT has a regulatory effect on the cytokines production, which might explain its beneficial effect in the treatment of CI.

Topics: Cerebral Infarction; Cytokines; Humans; In Vitro Techniques; Interleukin-10; Interleukin-4; Leukocytes, Mononuclear; Lipopolysaccharides; Phytohemagglutinins; Phytotherapy; Plant Extracts; Transforming Growth Factor beta; Transforming Growth Factor beta1

Both bone morphogenetic proteins (BMPs) and glial cell line-derived neurotrophic factor (GDNF) reduce ischemia-induced cerebral injury in rats. Intracerebral transplantation of fetal kidney tissue, which normally expresses BMPs and GDNF during development, reduces ischemic injury in cerebral cortex. In this study, we tested the hypothesis that BMP is involved in this neuroprotective response. Fetal kidney tissue was cut into small pieces and transplanted into cortical areas adjacent to the right middle cerebral artery (MCA) in adult rats. In situ hybridization of brain indicated that these fetal kidney transplants contained high levels of BMP-7 mRNA three days after grafting. Immunohistochemical analysis of grafted brain showed co-localization of BMP-7 and PAX-2 immunoreactivity in the graft, suggesting that these transplants contained BMP protein. Some animals were grafted with fetal kidney tissue after intraventricular administration (ICV) of the BMP antagonist noggin (1 micro g) or after vehicle, followed by MCA ligation for 60 min. Animals receiving fetal kidney tissue transplantation developed significantly less body asymmetry, as compared to stroke animals that either did not receive transplantation or received fetal kidney grafts and noggin pretreatment. Analysis of these brains after triphenyltetrazolium chloride staining showed that fetal kidney tissue transplantation reduced the volume of infarction in the cerebral cortex. Noggin pretreatment reduced the protection induced by fetal kidney grafting, although noggin itself did not cause increase in cerebral infarction. Eight hours after ischemia, brain homogenates were obtained from grafted and control animals to assay caspase-3 enzymatic activity. This analysis demonstrated that fetal kidney grafts significantly reduced ischemia-induced caspase-3 activity. Reduction of caspase-3 activity could also be antagonized by noggin pretreatment. In conclusion, our data suggest that fetal kidney transplantation reduces ischemia/reperfusion-induced cortical infarction and behavioral deficits in adult rats, which are, at least partially, mediated through the effect of BMPs from the transplants.

Topics: Animals; Bone Morphogenetic Protein 7; Bone Morphogenetic Proteins; Carrier Proteins; Caspase 3; Caspases; Cerebral Infarction; DNA-Binding Proteins; Fetal Tissue Transplantation; Functional Laterality; Glial Fibrillary Acidic Protein; Immunohistochemistry; In Situ Hybridization; Injections, Intraventricular; Kidney Transplantation; Ligation; Male; Middle Cerebral Artery; Motor Activity; PAX2 Transcription Factor; Proteins; Rats; Rats, Sprague-Dawley; Renal Circulation; RNA, Messenger; Stroke; Transcription Factors; Transforming Growth Factor beta

Several kidney cell lines were investigated for their ability to produce glial cell line-derived neurotrophic factor (GDNF). Cell line-conditioned medium was analyzed using ELISA and two cell lines were identified which produce GDNF in physiologically active concentrations. ELISA analyses revealed that conditioned medium from these two cell lines also contained PDGF, bFGF, TGFbeta1 and TGFbeta2. Both of these cell lines were then transplanted into the striatal penumbra of rats, 1 h following middle cerebral artery occlusion. Behavioral testing revealed that both cell lines reduced the deficit associated with cerebral ischemia and reduced the infarct volume relative to controls. Reduction of infarct volume was likely achieved by the action of GDNF and/or other growth factors produced by the cells.

Topics: Animals; Behavior, Animal; Brain Ischemia; Cell Line; Cell Transplantation; Cerebral Infarction; Enzyme-Linked Immunosorbent Assay; Fetal Tissue Transplantation; Fetus; Fibroblast Growth Factor 2; Glial Cell Line-Derived Neurotrophic Factor; Humans; Kidney; Male; Nerve Growth Factors; Nerve Tissue Proteins; Platelet-Derived Growth Factor; Rats; Rats, Sprague-Dawley; Transforming Growth Factor beta

Osteogenic protein-1 (OP1) not only possesses trophic activity on bone tissue but also influences neuronal survival and differentiation in vitro. Specific receptors for OP1 are present in brain and spinal cord and can be upregulated during cerebral contusion. OP1 is a member of the transforming growth factor-beta superfamily, several of whose members possess neuroprotective activity. In this study, the neuroprotective effect of OP1 in cerebral ischemia was evaluated in adult animals.. Adult male Sprague-Dawley rats were anesthetized with chloral hydrate. OP1 or vehicle was administered intracortically or intracerebroventricularly to the rats. Thirty minutes, 24 hours, or 72 hours after OP1 injection, the right middle cerebral artery (MCA) was ligated for 90 minutes. Twenty-four hours after reperfusion, animals were tested for motor behavior. The animals were subsequently anesthetized with urethane and perfused intracardially with saline. Brain tissue was removed, sliced, and incubated with 2% triphenyltetrazolium chloride to localize the area of infarction.. Only animals pretreated with OP1 24 hours before MCA ligation showed a reduction in motor impairment. OP1, given 30 minutes or 72 hours before MCA ligation, did not reduce cortical infarction. In contrast, pretreatment with OP1 24 hours before MCA ligation significantly attenuated the volume of infarction in the cortex, in agreement with the behavioral findings.. Intracerebral administration of OP1 24 hours before MCA ligation reduces ischemia-induced injury in the cerebral cortex.

Topics: Animals; Arterial Occlusive Diseases; Behavior, Animal; Bone Morphogenetic Protein 7; Bone Morphogenetic Proteins; Brain Ischemia; Cerebral Infarction; Ligation; Male; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Transforming Growth Factor beta

Various studies describe increased concentrations of transforming growth factor-beta (TGF-beta) in brain tissue after acute brain injury. However, the role of endogenously produced TGF-beta after brain damage to the CNS remains to be clearly established. Here, the authors examine the influence of TGF-beta produced after an episode of cerebral ischemia by injecting a soluble TGF-beta type II receptor fused with the Fc region of a human immunoglobulin (TbetaRIIs-Fc). First, this molecular construct was characterized as a selective antagonist of TGF-beta. Then, the authors tested its ability to reverse the effect of TGF-beta1 on excitotoxic cell death in murine cortical cell cultures. The addition of 1 microg/mL of TbetaRIIs-Fc to the exposure medium antagonized the neuroprotective activity of TGF-beta1 in N-methyl-D-aspartate (NMDA)-induced excitotoxic cell death. These results are consistent with the hypothesis that TGF-beta1 exerts a negative modulatory action on NMDA receptor-mediated excitotoxicity. To determine the role of TGF-beta1 produced in response to brain damage, the authors used a model of an excitotoxic lesion induced by the intrastriatal injection of 75 nmol of NMDA in the presence of 1.5 microg of TbetaRIIs-Fc. The intrastriatal injection of NMDA was demonstrated to induce an early upregulation of the expression of TGF-beta1 mRNA. Furthermore, when added to the excitotoxin, TbetaRIIs-Fc increased (by 2.2-fold, P < 0.05) the lesion size. These observations were strengthened by the fact that an intracortical injection of TbetaRIIs-Fc in rats subjected to a 30-minute reversible cerebral focal ischemia aggravated the volume of infarction. In the group injected with the TGF-beta1 antagonist, a 3.5-fold increase was measured in the infarction size (43.3 +/- 9.5 versus 152.8 +/- 46.3 mm3; P < 0.05). In conclusion, by antagonizing the influence of TGF-beta in brain tissue subjected to excitotoxic or ischemic lesion, the authors markedly exacerbated the resulting extent of necrosis. These results suggest that, in response to such insults, brain tissue responds by the synthesis of a neuroprotective cytokine, TGF-beta1, which is involved in the limitation of the extent of the injury. The pharmacologic potentiation of this endogenous defensive mechanism might represent an alternative and novel strategy for the therapy of hypoxic-ischemic cerebral injury.

Topics: Animals; Cell Death; Cells, Cultured; Cerebral Cortex; Cerebral Infarction; Fetus; Gene Expression Regulation; Humans; Immunoglobulin Fc Fragments; Ischemic Attack, Transient; Male; Mice; Middle Cerebral Artery; N-Methylaspartate; Neurons; Neuroprotective Agents; Protein Serine-Threonine Kinases; Rats; Rats, Sprague-Dawley; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Recombinant Fusion Proteins; Reverse Transcriptase Polymerase Chain Reaction; Transforming Growth Factor beta

Osteogenic protein-1 (OP-1, BMP-7) is a member of the transforming growth factor-beta (TGF-beta) superfamily that selectively induces dendritic outgrowth from cultured neurons. We injected human recombinant OP-1 (1 or 10 micrograms) or vehicle into the cisterna magna of mature male Sprague-Dawley rats 1 and 4 days after focal cerebral infarction induced by middle cerebral artery (MCA) occlusion. OP-1 treatment was associated with a marked enhancement of recovery of sensorimotor function of the impaired forelimb and hindlimb (contralateral to infarcts) as assessed by limb placing tests. This effect appeared to be dose dependent. There was no difference in infarct volume between OP-1 and vehicle-treated rats. The mechanisms of enhanced recovery by intracisternal OP-1 may include promotion of dendritic sprouting in the intact uninjured brain.

Topics: Analysis of Variance; Animals; Body Weight; Bone Morphogenetic Protein 7; Bone Morphogenetic Proteins; Brain; Cerebral Infarction; Cisterna Magna; Forelimb; Humans; Ischemic Attack, Transient; Male; Microinjections; Motor Activity; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Time Factors; Transforming Growth Factor beta

It is known that transforming growth factor beta (TGF-beta) is involved in the modulation of cell growth, differentiation, and repair following injury. We performed an immunohistochemical study of human brain autopsy and biopsy material for the expression of TGF-beta isoforms beta 1, beta 2 and beta 3, and TGF-beta receptor (T beta R) type I in different cells of necrotizing lesions such as infarction and abscess, and compared them with controls. Various cell types, both inside and in the proximity of lesions, showed immunoreactivity indicating the presence of all three isoforms. Significant values of immunoreaction for various TGF-beta s and T beta R-I were observed in cells such as astrocytes, macrophages, neurons, microvascular endothelial cells, and granulocytes. In the control cases, comprising biopsy material without necrotizing lesions, a prominent TGF-beta 2 immunoreactivity was observed in glial cells and neurons. TGF-beta 1 and TGF-beta 3 reactivity in controls, when compared with TGF-beta 2, was less. T beta R-I antiserum showed clear and distinct signals in the same type of cells as for TGF-beta s in the necrotizing lesions with varying values of significance. Our findings suggest that TGF-beta s and their receptor type I are involved in reactive processes around necrotizing human brain lesions like glial and macrophage responses, angiogenesis, and deposition of extracellular matrix.

Topics: Adult; Aged; Aged, 80 and over; Brain; Brain Abscess; Brain Chemistry; Cerebral Infarction; Female; Humans; Immunohistochemistry; Male; Middle Aged; Necrosis; Receptors, Transforming Growth Factor beta; Transforming Growth Factor beta

Occlusion in cerebral vessels results in ischemic stroke and is followed by proliferation of microvessels, ie, angiogenesis. The process is particularly marked in the border zone of the infarct, known as the ischemic penumbra. This increase in vascularization is likely to be caused by the action of angiogenic factors, such as TGF-beta 1, which is a powerful regulator of angiogenesis.. In this study we examined 10 brain samples from patients who suffered from ischemic stroke for the expression of mRNA encoding TGF-beta 1.. The ischemic penumbra contained the highest levels of TGF-beta 1 mRNA, whereas the normal contralateral hemispheres had the least (P < .001, Mann-Whitney U test). Unlike those from normal brain, protein extracts from infarcted tissue contained active TGF-beta 1 as a 25-kD band in Western blot analysis. Extracts from the penumbra also contained a 12.5-kD isoform of TGF-beta 1. Both penumbra and infarct contained TGF-beta 1 immunoreactive products as assessed with immunohistochemistry, whereas very weak staining was observed in the contralateral hemisphere.. These results suggest that TGF-beta 1 is important in the pathogenesis of the angiogenic response in ischemic brain tissue and its modulation may be used for therapeutic purposes.

Topics: Aged; Aged, 80 and over; Astrocytes; Autopsy; Blotting, Western; Brain; Brain Ischemia; Cerebellum; Cerebral Infarction; DNA Probes; Endothelium, Vascular; Female; Functional Laterality; Gene Expression; Humans; In Situ Hybridization; Male; Middle Aged; Neurons; RNA, Messenger; Transforming Growth Factor beta

Based upon the hypothesis that growth regulatory and inflammatory mechanisms participate in the pathogenesis of Alzheimer's disease, we studied cases of Alzheimer's disease for immunoreactivity to each of the three mammalian transforming growth factor beta (TGF-beta) isotypes: TGF-beta 1, TGF-beta 2, TGF-beta 3. Results were compared with those seen in control brains and in a destructive pathological process, subacute infarction. In the cases of Alzheimer's disease, TGF-beta 1 immunoreactivity was limited to neuritic profiles within senile plaques. Neuronal neurofibrillary tangles, plaque neurites, microglia, astrocytes and macrophages expressed TGF-beta 2 immunoreactivity. TGF-beta 3 produced strikingly selective staining of Hirano bodies. In contrast, in cases with infarction, reactive astrocytes and macrophages were positive with all three antibodies. Ramified microglia labeled selectively, as in the Alzheimer brains, with the TGF-beta 2 antibody. Subtle generalized astrocyte and microglial immunoreactivity for TGF-beta 2 was seen in pathological and control brains. The localization of TGF-beta isotypes to the lesions of Alzheimer's disease supports the hypothesis that these cytokines may influence lesion expression. Their presence in reactive cells associated with cerebral infarction suggest that they may play a broader role in the pathogenesis of CNS disease.

Topics: Aging; Alzheimer Disease; Animals; Cerebral Infarction; Gene Expression; Humans; Immunohistochemistry; Mice; Mice, Inbred Strains; Microglia; Transforming Growth Factor beta

Transforming growth factor-beta 1 (TGF-beta 1) mRNA is induced from 5 h to 3 days following hypoxic-ischaemic brain injury. Cell death also develops during this time suggesting that extracellular accumulation of this peptide may be involved in the processes that regulate cell loss. We examined the effect of rhTGF-beta 1 (0,2.5, 10,50 ng) injected into the cerebral lateral ventricle of rats 2 h after severe hypoxic-ischaemic brain injury. Histological outcome and B4-isolectin histochemistry were assessed 5 and 2 days, respectively following hypoxia. Treatment with 10 ng TGF-beta 1 reduced the microglia reaction (p < 0.05), the magnitude of neuronal loss (p < 0.01) and the area of cortical infarction (p < 0.05). Exogenous TGF-beta 1 given soon after hypoxic-ischaemic brain injury may have therapeutic potential and act by inhibiting the microglial reaction.

Topics: Animals; Brain Ischemia; Cell Death; Cerebral Infarction; Histocytochemistry; Hypoxia, Brain; Injections, Intraventricular; Lectins; Male; Microglia; Neurons; Rats; Rats, Wistar; Transforming Growth Factor beta

The aim of this study was to examine the effect of transforming growth factor-beta 1, a cytokine shown to amelioriate cardiac ischemia, in a rabbit model of thromboembolic stroke.. An autologous clot embolus was introduced intracranially through the right internal carotid artery in 21 New Zealand White rabbits, with seven in each group receiving either vehicle control (albumin) or 10 or 50 micrograms transforming growth factor-beta 1 administered as an intracarotid bolus immediately before autologous clot embolization. Multiple physiological parameters were monitored, including regional cerebral blood flow, arterial blood gases, hematocrit, glucose, core temperature, and mean arterial pressure. The brain was harvested 4 hours after embolization, and infarct size was determined planimetrically as a percentage of the entire hemisphere.. Brain infarct size was reduced in both the 10-microgram (16.7 +/- 4.0% [mean +/- SEM], p < 0.05) and 50-microgram (21.7 +/- 4.5%) transforming growth factor-beta 1-treated groups when compared with the control group (31.9 +/- 6.6%). Regional cerebral blood flow did not show any significant intergroup or intragroup variation over time, although the 10-microgram transforming growth factor-beta 1 group experienced a greater return of cerebral blood flow in the first 2 hours after embolization.. Transforming growth factor-beta 1 reduced brain infarct size in a rabbit model of thromboembolic stroke. This effect was not related to a direct effect on blood flow. Studies are ongoing to determine the mechanism by which transforming growth factor-beta 1 salvages ischemic brain.

Topics: Animals; Blood Glucose; Brain Ischemia; Cerebral Infarction; Cerebrovascular Circulation; Female; Isomerism; Male; Rabbits; Reference Values; Transforming Growth Factor beta