Title:Dietary and Plant Polyphenols Exert Neuroprotective Effects and Improve Cognitive Function in Cerebral Ischemia
VOLUME: 5 ISSUE: 2
Author(s):Kiran S. Panickar and Saebyeol Jang
Affiliation:Diet, Genomics, & Immunology Laboratory, Beltsville Human Nutrition Research Center, 10300 Baltimore Ave, Bldg 307C, ARS/USDA, Beltsville, MD 20705, USA.
Keywords:Apoptosis, brain edema, cytokines, excitotoxicity, memory, stroke.
Abstract:Cerebral ischemia is caused by an interruption of blood flow to the brain which generally leads to irreversible
brain damage. Ischemic injury is associated with vascular leakage, inflammation, tissue injury, and cell death. Cellular
changes associated with ischemia include impairment of metabolism, energy failure, free radical production, excitotoxicity,
altered calcium homeostasis, and activation of proteases all of which affect brain functioning and also contribute to longterm
disabilities including cognitive decline. Inflammation, mitochondrial dysfunction, increased oxidative/nitrosative stress, and
intracellular calcium overload contribute to brain injury including cell death and brain edema. However, there is a paucity of
agents that can effectively reduce cerebral damage and hence considerable attention has focused on developing newer agents
with more efficacy and fewer side-effects. Polyphenols are natural compounds with variable phenolic structures and are rich in
vegetables, fruits, grains, bark, roots, tea, and wine. Most polyphenols have antioxidant, anti-inflammatory, and anti-apoptotic
properties and their protective effects on mitochondrial functioning, glutamate uptake, and regulating intracellular calcium
levels in ischemic injury in vitro have been demonstrated. This review will assess the current status of the potential effects
of polyphenols in reducing cerebral injury and improving cognitive function in ischemia in animal and human studies. In
addition, the review will also examine available patents in nutrition and agriculture that relates to cerebral ischemic injury
with an emphasis on plant polyphenols.