Bruton’s tyrosine kinase inhibitors in brain diseases

Bruton’s tyrosine kinase (BTK) is a non-receptor-bound intracellular signaling protein. It is well known for its importance in the growth and malignancy of B cells, but recent studies suggested that the BTK is also associated with many other innate immune cells. As reported, a comparatively high level of BTK expression can be observed in monocytes, neutrophils, macrophages, and even central nervous system-resident immune cells like microglia. This suggests that BTK activation occurs in various acute and chronic inflammatory conditions. Here, we discuss how BTK inhibitors might be used to treat certain conditions, concentrating on ischemic stroke, multiple sclerosis, neuromyelitis optica spectrum disorders, and Alzheimer’s disease. We specifically show the significance of targeting B cells in controlling the inflammatory component of the disease in multiple sclerosis treatment. In addition, we draw attention to the role of BTK in the NLRP3 inflammasome activation, which is essential for brain damage and neuroinflammation. In summary, we conclude that therapeutic targeting of BTK in brain diseases is a potential strategy that can complement the existing therapies.