Roya Lari; Peter Kitchener
Abstract
Microglia cells are a subset of central nervous system (CNS) macrophages. Changes in the CNS such as injury, or developmental events, follow by morphological and physiological changes in microglia cells. In this study organotypic brain slice cultures under serum free condition were used to investigate ...
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Microglia cells are a subset of central nervous system (CNS) macrophages. Changes in the CNS such as injury, or developmental events, follow by morphological and physiological changes in microglia cells. In this study organotypic brain slice cultures under serum free condition were used to investigate the morphology and lectin histochemistry of microglia and macrophages in the CNS in vitro. Microglial cells exhibited dramatic morphological changes in the organotypic brain slice culture. Immediately after slicing microglias were seen to have the same morphology as they do in the intact brain: they had small cell bodies from which radiated several highly ramified processes. After 1 day in vitro all microglia transformed into an active form with round soma and no processes. At 5 days in vitro, and especially at 9 days in vitro, many of the microglia had tended to return to the ramified phenotype. The expression of different carbohydrates was examined at the 0, 1, 5 and 9 days in vitro time periods by employing Lycopersicon esculentum tomato lectin (LEL lectins) and Sambucus nigra (SNA). Microglial cells with different morphology intensely stained with LEA . SNA stained the ramified microglia only after they re-ramified at 5 DIV and 9 DIV. The results of this study confirmed that the expression of carbohydrate structures in these cells would undergo changes commensurate with the changes in morphology.
Soraya Abbasi Habashi; Farzaneh Sabouni; Ali Moghimi; Saeed Ansari Majd; Azita Parvaneh Tafreshi
Abstract
Microglia, the sentries of the brain, is highly implicated in neurodegeneration as in neuroprotection. Chronic microglial activation endangers neuronal survival through the release of various potentially neurotoxic mediators including Nitric Oxide (NO). Thus, negative regulators of microglial activation ...
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Microglia, the sentries of the brain, is highly implicated in neurodegeneration as in neuroprotection. Chronic microglial activation endangers neuronal survival through the release of various potentially neurotoxic mediators including Nitric Oxide (NO). Thus, negative regulators of microglial activation have been considered as potential therapeutic candidates to target neurodegeneration, such as those in Alzheimer’s and Parkinson’s diseases and even in chronic epileptic syndromes. Bromelain, a mixture of cysteine proteases, derived from pineapple stem, has been reported to have anti-inflammatory and immunomodulatory effects. Neonatal rat primary microglial cells were isolated from the brain according to the Floden’s method. The purity of the cultures was determined by immunostaining with an OX-42 antibody which showed a purity greater than 95%.The activation profile of microglia was investigated by determining the effects of Bromelain (1, 10, 20, 30, 40 and 50 μg/ml) on the level of neurotoxin, NO, mitochondrial activity and morphological changes in treated microglia with lipopolysaccharide (LPS) (1μg/ml), as an endotoxin. Our results showed that pretreatment of primary rat microglia with bomelain (30 μg/ml), decreased the production of NO induced by LPS (1μg/ml) treatment in a dose-dependent manner, which prevented the deramification of microglia and its phagocytic morphology. Moreover, bromelain does not show cytotoxicity at any of the applied doses, suggesting that the anti-inflammatory effects of bromelain are not due to the cell death. In conclusion, Bromelain reduces the NO synthesis in vitro by potentially exerting its anti-inflammatory effects. Bromelain naturally found in pineapple stem, can be considered as a useful agent for neuroprotection and alleviation of symptoms in neurodegenerative diseases.
