ABSTRACT
Periventricular germinal matrix hemorrhage is a devastating complication of preterm birth. Inflammation appears to play a role in brain damage after premature birth and hypoxia. The effects of rat blood plasma and serum on cytokine expression by cultured rat microglial cells were investigated. We analyzed mRNA expression levels of tumor necrosis factor (TNF)-alpha, interleukin-6 and protease activated receptor-1 and -4 by quantitative RT-PCR. Protein expression for TNFalpha was done using immunocytochemistry and ELISPOT assays. Plasma and serum had dose dependent toxic effects on microglia as measured by lactate dehydrogenase release assay and activated caspase-3 immunocytochemistry. High concentrations of plasma enhanced TNFalpha mRNA expression and protein production, while high concentrations of serum enhanced IL-6 mRNA expression. This study suggests that soluble components of blood might be differentially responsible for up regulating production of the cytokines TNFalpha and IL-6 by microglia from immature rodent brain.
Subject(s)
Blood Proteins/immunology , Cytokines/metabolism , Encephalitis/immunology , Microglia/immunology , Microglia/metabolism , Animals , Animals, Newborn , Birth Injuries/immunology , Birth Injuries/metabolism , Birth Injuries/physiopathology , Blood Proteins/pharmacology , Caspase 3/drug effects , Caspase 3/metabolism , Cells, Cultured , Cerebral Hemorrhage/immunology , Cerebral Hemorrhage/metabolism , Cerebral Hemorrhage/physiopathology , Cytokines/genetics , Dose-Response Relationship, Drug , Encephalitis/etiology , Encephalitis/metabolism , Immunohistochemistry , Interleukin-6/genetics , Interleukin-6/metabolism , L-Lactate Dehydrogenase/drug effects , L-Lactate Dehydrogenase/metabolism , Premature Birth/immunology , Premature Birth/metabolism , Premature Birth/physiopathology , RNA, Messenger/drug effects , RNA, Messenger/metabolism , Rats , Receptor, PAR-1/drug effects , Receptor, PAR-1/genetics , Receptor, PAR-1/metabolism , Receptors, Proteinase-Activated/drug effects , Receptors, Proteinase-Activated/genetics , Receptors, Proteinase-Activated/metabolism , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism , Up-Regulation/drug effects , Up-Regulation/genetics , Up-Regulation/immunologyABSTRACT
Perinatal hypoxic-ischemic (HI) brain damage is a major cause of mortality and neurological morbidity in infants and children. Using an established model of unilateral hypoxia-ischemia in neonatal rats, the present study focused on mast cells (MCs), important regulators of inflammatory processes, as potential contributors to HI damage. MCs are present in the pia of the neonatal rat, entering the central nervous system (CNS) during cerebral development along penetrating blood vessels. Following hypoxia-ischemia, MC numbers increased dramatically in the ipsilateral (ischemic) hemisphere (p < 0.01). In animals exposed to hypoxia only, the numbers of MCs were elevated in both hemispheres to an extent equal to that observed in the contralateral hemisphere of HI animals (p < 0.05 vs. control). Within damaged areas (ipsilateral only), MCs were observed in regions of activated microglia and astroglia that characterize the ischemic hemisphere. Using a triple-label paradigm, MCs were observed along elongating blood vessels, some of which express the GLUT1 isoform of the glucose transporter protein, indicative of blood-brain barrier vessels. To determine whether MC activation has a role in HI brain damage, rat pups were treated with the MCs stabilizer, disodium cromoglycate (cromolyn), prior to and/or following hypoxia-ischemia. The cromolyn treatment inhibited MC migration into the CNS (p < 0.05) and limited brain damage more than 50% (p < 0.01) vs. saline controls. These data support the hypothesis that MCs are key contributors to the extent of brain damage due to hypoxia-ischemia in the immature animal.
Subject(s)
Birth Injuries/physiopathology , Chemotaxis, Leukocyte/immunology , Cromolyn Sodium/pharmacology , Encephalitis/physiopathology , Hypoxia-Ischemia, Brain/physiopathology , Mast Cells/immunology , Aging/immunology , Animals , Animals, Newborn , Anti-Asthmatic Agents/pharmacology , Anti-Asthmatic Agents/therapeutic use , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Birth Injuries/drug therapy , Birth Injuries/immunology , Blood-Brain Barrier/immunology , Blood-Brain Barrier/physiopathology , Brain/drug effects , Brain/growth & development , Brain/physiopathology , Chemotaxis, Leukocyte/drug effects , Cromolyn Sodium/therapeutic use , Disease Models, Animal , Encephalitis/drug therapy , Encephalitis/immunology , Endothelial Cells/metabolism , Gliosis/immunology , Gliosis/physiopathology , Glucose Transporter Type 1/metabolism , Hypoxia-Ischemia, Brain/drug therapy , Hypoxia-Ischemia, Brain/immunology , Mast Cells/drug effects , Rats , Rats, Wistar , Treatment OutcomeABSTRACT
Pediatric patients in early childhood presenting with perinatal affection of the nervous system benefit much from incorporation into their combined treatment of multivitamins "Multitabs", as evidenced by improvement in their general health, as well as in the red blood parameters and immunity status. Thus, use of the above multivitamins for children presenting with perinatal cerebral pathology is considered liable to be of benefit making for optimization of the process of treatment.