Seasonal consumption of polyphenol-rich fruits affects the hypothalamic leptin signaling system in a photoperiod-dependent mode

Sci Rep. 2018 Sep 11;8(1):13572. doi: 10.1038/s41598-018-31855-y.


Leptin has a central role in the maintenance of energy homeostasis, and its sensitivity is influenced by both the photoperiod and dietary polyphenols. The aim of this study was to investigate the effect of seasonal consumption of polyphenol-rich fruits on the hypothalamic leptin signaling system in non-obese and obese animals placed under different photoperiods. Non-obese and diet-induced obese male Fischer 344 rats were placed under either a short-day (SD) or long-day (LD) photoperiod and were supplemented with either 100 mg/kg of lyophilized red grapes or cherries. In non-obese animals, both fruits reduced energy balance independent of the photoperiod to which they were placed. However, the hypothalamic gene expression of Pomc was significantly up-regulated only in the SD photoperiod. In contrast, in obese animals only cherry significantly decreased the energy balance, although both fruits were able to counteract the diet-induced increase in hypothalamic AgRP mRNA levels when consumed during the SD photoperiod. In conclusion, the consumption of rich-polyphenol fruits may increase leptin sensitivity through the modulation of the hypothalamic leptin signal pathway mainly when consumed in the SD photoperiod. Therefore, fruit seasonality should be considered, as it can influence energy homeostasis and obesity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agouti-Related Protein / genetics
  • Agouti-Related Protein / metabolism
  • Animals
  • Diet, High-Fat / adverse effects
  • Energy Metabolism / drug effects
  • Energy Metabolism / genetics*
  • Energy Metabolism / radiation effects
  • Freeze Drying
  • Fruit / chemistry
  • Gene Expression Regulation
  • Homeostasis / drug effects
  • Homeostasis / genetics
  • Homeostasis / radiation effects
  • Hypothalamus / drug effects
  • Hypothalamus / metabolism*
  • Hypothalamus / radiation effects
  • Leptin / genetics
  • Leptin / metabolism*
  • Light
  • Male
  • Obesity / etiology
  • Obesity / genetics
  • Obesity / metabolism*
  • Photoperiod
  • Polyphenols / administration & dosage*
  • Proprotein Convertases / genetics
  • Proprotein Convertases / metabolism
  • Prunus avium / chemistry
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Inbred F344
  • Signal Transduction*
  • Vitis / chemistry


  • AGRP protein, rat
  • Agouti-Related Protein
  • Leptin
  • Polyphenols
  • RNA, Messenger
  • Proprotein Convertases