Effect of photoperiod and seasonal fruit supplementation on hypothalamic neuropeptides regulated by leptin in non-obese animals. Hypothalamic gene expression of neuropeptides evaluated by quantitative PCR on animals fed standard chow diet + vehicle or 100 mg/kg of lyophilized grapes (A) or cherries (B) for 10-week-period and submitted to long-day (LD) or short-day (SD) photoperiods. Values were normalized against LD-vehicle group. Data represent mean ± SE (n = 6). P, photoperiod effect; F, fruit effect; F*P, and interaction of photoperiod and fruit treatment assessed by two-way ANOVA (P ≤ 0.05). Different letters denote significant changes assessed by one-way ANOVA and Tukey’s post hoc test (P < 0.05).