Emerging paradigms in nanotechnology for imaging and treatment of cerebral ischemia

Cerebral ischemia is a deadly condition that arises due to blockage of the blood vessels in the brain leading to oxygen deficiency thereby arresting brain functions and resulting in death or permanent impairment. Though a myriad of factors has been proposed to cause cerebral ischemia, it has been generally regarded as an old age-associated malady. However, unhealthy diet, stressful lifestyle and deteriorating environment quality has dramatically reduced the age on onset as well as the number of victims in recent years. Hence, there exists a need for prompt and effective therapeutic strategies for immediate as well as long-term damage control and maintenance of the functions of the brain, as well as early and accurate diagnosis of the risk of stroke or extent of damage after stroke. The physiological barriers further complicate the development of therapeutic and diagnostic interventions for cerebral stroke. The advent of nanotechnology has initiated new vistas for more effective and superior therapeutic and imaging modalities for management of cerebral ischemia. This review provides an overview on the current knowledge on the mechanism and causative factors of cerebral ischemia, drawbacks of conventional therapy as well as molecular targets that are being explored for stroke therapy. The review also discusses in detail the advances made using nano-interventions for therapy and imaging of stroke-affected regions along with their pros and cons. Emergent multi-functional nanoparticles for stroke management have also been reviewed.