Population aging is occurring rapidly worldwide, challenging the global economy and healthcare services. Brain aging is a significant contributor to various age-related neurological and neuropsychological disorders, including Alzheimer’s disease and Parkinson’s disease. Several extrinsic factors, such as exposure to ionizing radiation, can accelerate senescence. Multiple human and animal studies have reported that exposure to ionizing radiation can have varied effects on organ aging and lead to the prolongation or shortening of life span depending on the radiation dose or dose rate. This paper reviews the effects of radiation on the aging of different types of brain cells, including neurons, microglia, astrocytes, and cerebral endothelial cells. Further, the relevant molecular mechanisms are discussed. Overall, this review highlights how radiation-induced senescence in different cell types may lead to brain aging, which could result in the development of various neurological and neuropsychological disorders. Therefore, treatment targeting radiation-induced oxidative stress and neuroinflammation may prevent radiation-induced brain aging and the neurological and neuropsychological disorders it may cause.
28 July 2011 in Pflügers Archiv - European Journal of Physiology
Neurotransmitter and receptor systems are involved in different neurological and neuropsychological disorders such as Parkinson's disease, depression, Alzheimer’s disease and epilepsy. Recent advances in studies of signal transduction pathways or interacting proteins of neurotransmitter receptor systems suggest that different receptor systems may share the common signal transduction pathways or interacting proteins which may be better therapeutic targets for development of drugs to effectively control brain diseases. In this paper, we reviewed metabotropic glutamate receptors (mGluRs) and their related signal transduction pathways or interacting proteins in status epilepticus and temporal lobe epilepsy, and proposed some novel therapeutical drug targets for controlling epilepsy and epileptogenesis.
Background: Brain exposure to ionizing radiation during the radiotherapy of brain tumor or metastasis of peripheral cancer cells to the brain has resulted in cognitive dysfunction by reducing neurogenesis in hippocampus. The water extract of Lycium barbarum berry (Lyc), containing water-soluble Lycium barbarum polysaccharides and flavonoids, can protect the neuronal injury by reducing oxidative stress and suppressing neuroinflammation. Reseach Design: To demonstrate the long-term radioprotective effect of Lyc, we evaluated the neurobehavioral alterations and the numbers of NeuN, calbindin (CB), and parvalbumin (PV) immunopositive hippocampal neurons in BALB/c mice after acute 5.5 Gy radiation with/without oral administration of Lyc at the dosage of 10 g/kg daily for 4 weeks. Results: The results showed that Lyc could improve irradiation-induced animal weight loss, depressive behaviors, spatial memory impairment, and hippocampal neuron loss. Immunohistochemistry study demonstrated that the loss of NeuN-immunopositive neuron in the hilus of the dentate gyrus, CB-immunopositive neuron in CA1 strata radiatum, lacunosum moleculare and oriens, and PV-positive neuron in CA1 stratum pyramidum and stratum granulosum of the dentate gyrus after irradiation were significantly improved by Lyc treatment. Conclusion: The neuroprotective effect of Lyc on those hippocampal neurons may benefit the configuration of learning related neuronal networks and then improve radiation induced neurobehavioral changes such as cognitive impairment and depression. It suggests that Lycium barbarum berry may be an alternative food supplement to prevent radiation-induced neuron loss and neuropsychological disorders.