Inflammation and the Brain Disorders: A Review

Inflammation is a physiological response of immune system against internal and external harmful stimulus. However, inflammation is a double-edged sword and can be harmful if it is not properly controlled. Nowadays inflammation is considered as an important factor in the pathophysiology of neurological diseases. Neuroinflammation can be as a result of direct damage to the brain tissues or induced by systemic inflammation. This process is characterized by microglial activation, stimulates astrocytes, blood - brain barrier breakdown and consequent increase in the permeability, penetration of peripheral immune cells into parenchyma of the central nervous system, excessive production of cytokines, nitric oxide, reactive oxygen species as well as prostaglandins and finally, neuronal damage and death. In this study, neuroinflammation and its role in the pathophysiology of brain diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, depression, anxiety, epilepsy, schizophrenia and autism are outlined and discussed.
Although inflammation has a prominent role in the pathogenesis of neurological diseases, there are no effective and safe treatments to control deregulated inflammatory processes in the brain. The medications usually used to control inflammation are not fully effective in the brain due to lack of BBB penetration. Since many inflammatory processes in the brain is beneficial, modulation of inflammatory responses will be a more efficient therapeutic approach than suppression of inflammatory processes.