Bee pollen improves muscle protein and energy metabolism in malnourished old rats through interfering with the Mtor signaling pathway and mitochondrial activity

Nutrients. 2014 Dec 1;6(12):5500-16. doi: 10.3390/nu6125500.

Abstract

Although the management of malnutrition is a priority in older people, this population shows a resistance to refeeding. Fresh bee pollen contains nutritional substances of interest for malnourished people. The aim was to evaluate the effect of fresh bee pollen supplementation on refeeding efficiency in old malnourished rats. Male 22-month-old Wistar rats were undernourished by reducing food intake for 12 weeks. The animals were then renourished for three weeks with the same diet supplemented with 0%, 5% or 10% of fresh monofloral bee pollen. Due to changes in both lean mass and fat mass, body weight decreased during malnutrition and increased after refeeding with no between-group differences (p < 0.0001). Rats refed with the fresh bee pollen-enriched diets showed a significant increase in muscle mass compared to restricted rats (p < 0.05). The malnutrition period reduced the muscle protein synthesis rate and mTOR/p70S6kinase/4eBP1 activation, and only the 10%-pollen diet was able to restore these parameters. Mitochondrial activity was depressed with food restriction and was only improved by refeeding with the fresh bee pollen-containing diets. In conclusion, refeeding diets that contain fresh monofloral bee pollen improve muscle mass and metabolism in old, undernourished rats.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adiposity
  • Age Factors
  • Animals
  • Bees*
  • Carrier Proteins / metabolism
  • Cytokines / blood
  • Dietary Supplements*
  • Disease Models, Animal
  • Energy Metabolism*
  • Intracellular Signaling Peptides and Proteins
  • Male
  • Mitochondria, Muscle / metabolism*
  • Muscle, Skeletal / metabolism*
  • Muscle, Skeletal / physiopathology
  • Nutritional Status*
  • Phosphoproteins / metabolism
  • Pollen*
  • Protein-Energy Malnutrition / blood
  • Protein-Energy Malnutrition / diet therapy*
  • Protein-Energy Malnutrition / enzymology
  • Protein-Energy Malnutrition / physiopathology
  • Rats, Wistar
  • Ribosomal Protein S6 Kinases, 70-kDa / metabolism
  • Signal Transduction*
  • TOR Serine-Threonine Kinases / metabolism*
  • Weight Gain

Substances

  • Carrier Proteins
  • Cytokines
  • Eif4ebp1 protein, rat
  • Intracellular Signaling Peptides and Proteins
  • Phosphoproteins
  • TOR Serine-Threonine Kinases
  • mTOR protein, rat
  • Ribosomal Protein S6 Kinases, 70-kDa