Anti-ischemia/reperfusion injury effects of notoginsenoside R1 on small molecule metabolism in rat brain after ischemic stroke as visualized by MALDI–MS imaging

In the adult brain, new neurons are continuously generated in the subventricular zone and dentate gyrus, but it is unknown whether these neurons can replace those lost following damage or disease. Here we show that stroke, caused by transient middle cerebral artery occlusion in adult rats, leads to a marked increase of cell proliferation in the subventricular zone. Stroke-generated new neurons, as well as neuroblasts probably already formed before the insult, migrate into the severely damaged area of the striatum, where they express markers of developing and mature, striatal medium-sized spiny neurons. Thus, stroke induces differentiation of new neurons into the phenotype of most of the neurons destroyed by the ischemic lesion. Here we show that the adult brain has the capacity for self-repair after insults causing extensive neuronal death. If the new neurons are functional and their formation can be stimulated, a novel therapeutic strategy might be developed for stroke in humans.

In the past decade, the definition of stroke has been revised and major advances have been made for its treatment and prevention. For acute ischaemic stroke, the addition of endovascular thrombectomy of proximal large artery occlusion to intravenous alteplase increases functional independence for a further fifth of patients. The benefits of aspirin in preventing early recurrent ischaemic stroke are greater than previously recognised. Other strategies to prevent recurrent stroke now include direct oral anticoagulants as an alternative to warfarin for atrial fibrillation, and carotid stenting as an alternative to endarterectomy for symptomatic carotid stenosis. For acute intracerebral haemorrhage, trials are ongoing to assess the effectiveness of acute blood pressure lowering, haemostatic therapy, minimally invasive surgery, anti-inflammation therapy, and neuroprotection methods. Pharmacological and stem-cell therapies promise to facilitate brain regeneration, rehabilitation, and functional recovery. Despite declining stroke mortality rates, the global burden of stroke is increasing. A more comprehensive approach to primary prevention of stroke is required that targets people at all levels of risk and is integrated with prevention strategies for other diseases that share common risk factors.