Ginseng (Panax quinquefolius), is a Traditional Chinese Medicinal herb, with previous research suggesting that an the ginseng active component, Ginsenoside Rb1(GRb1), exerts neuroprotective effects or for cerebral ischemia (stroke). In that some studies have proposed the beneficial impact may be due to the effects on brain-derived neurotrophic factor (BDNF) -- a protein that helps to support the survival of existing neurons, and encourages the growth and differentiation of new neurons and in the brain, while other research has linked levels of caspase-3 -- a protein that is vital in the cycle of programmed cell death and has been shown to be elevated after certain cardiovascular events, Qiong-Lan Yuan, from Tongji University School of Medicine (China), and colleagues explored the underlying mechanism of the neuroprotective effects of GRb1.  The team observed expressions of BDNF and caspase-3 and neurogenesis in rats with experimental cerebral ischemia, finding that GRb1 infusion after cerebral ischemia significantly promoted recoveries of neurological functions at three and five days post-stroke, as compared to ischemic rats not infused with GRb1.  The researchers also reported that BDNF levels were significantly increased in GRb1-treated rats, whilst infusion with GRb1 post- stroke was shown to significantly reduce levels of caspase-3, as compared to control rats. Importantly, the team found that GRb1 significantly increased the number of neural stem cells – known as neural precursors cells – after ischemic stroke.