HDAC6 and Alzheimer disease: There is some evidence suggesting that deacetylase activity of HDAC6 promotes inflammatory responses [45,46]; conversely, pharmacological inhibition of HDAC6 appears to attenuate inflammation in the progression of multiple neurodegenerative diseases or conditions such as PD, Alzheimer’s disease and Huntington’s disease [47,48,49,50], or retinal injury [51].