Mediterranean diet protects against a neuroinflammatory cortical transcriptome: Associations with brain volumetrics, peripheral inflammation, social isolation, and anxiety in nonhuman primates (Macaca fascicularis)

•Mediterranean diet is associated with lower expression of proinflammatory pathways.•Mediterranean diet is associated with higher expression of neuroprotective pathways.•Mediterranean diets may confer protection against peripheral & central inflammation.•Mediterranean diet may help to preserve brain structure and socioemotional behavior.•Nonhuman primates are useful models for studying diet effects on the body & brain. Mediterranean diets may be neuroprotective and prevent cognitive decline relative to Western diets; however, the underlying biology is poorly understood. We assessed the effects of Western versus Mediterranean-like diets on RNAseq-generated transcriptional profiles in lateral temporal cortex and their relationships with longitudinal changes in neuroanatomy, circulating monocyte gene expression, and observations of social isolation and anxiety in 38 socially-housed, middle-aged female cynomolgus macaques (Macaca fascicularis). Diet resulted in differential expression of seven transcripts (FDR