MMP might also influence the risk of CSVD; one previous study suggests that mice models exposed to MMP-2 inhibitor exhibited lessened white matter lesions and microglia and astroglia activation following chronic cerebral hypoperfusion [38], while clinical studies in ischaemic stroke patients with a high burden of CSVD found an independent association with elevated MMP-9 and TIMP-4 [39, 40]. The gene discussed is TIMP4; the disease is ischemic stroke.