Poster Presentation The International Congress of Neuroendocrinology 2014

Childhood maltreatment including neglect is an example of early life adversity, and its incidence is reported to be drastically increasing across the globe. Thus, it is a critical public health issue. Childhood maltreatment is a major contributor to several psychological disorders particularly anxiety in later life. Humans commonly binge on palatable diet as a strategy to cope with stress. Therefore, we modelled early life adversity using limited nesting material (LN) in rats and examined if palatable high fat/sugar diet (HFHS) would reverse the heightened anxiety-like behaviour induced by early life adversity. Rat pups and their dams were provided with a metal grid, a half paper towel and no bedding from postnatal days 2-9, thereby creating a harsh early environment for the pups and dams. One common feature of childhood maltreatment is lack of maternal care. This model resembles a human condition, where the mother is present but care is fragmented¹. Our data revealed that LN resulted in increased anxiety-like behaviour at 7 weeks of age as assessed with elevated plus maze. LN pups exhibited a lower percentage of entries into the open arm versus control pups (15.62±1.92 versus 24.98±2.37). Interestingly, LN pups consuming HFHS almost doubled the entries into open arms versus LN pups consuming chow (30.50±3.06 versus 15.60±1.9, p<0.01). While the HFHS reversed anxiety-like behaviour induced by LN, it produced long-term suppression of expression in genes related to neurogenesis and mitochondrial biogenesis in those rats exposed to LN versus unstressed control rats consuming the same diet (table 1). This study reveals for the first time that consumption of a poor diet during adulthood following early adversity increases the risk of developing neuropsychiatric diseases and is associated with deficits in hippocampal mitochondrial biogenesis and plasticity.