Chronic Oral Administration of Tenebrio molitor Extract Exhibits Inhibitory Effect on Glucocorticoid Receptor Overexpression in the Hippocampus of Ovariectomy-Induced Estrogen Deficient Mice

J Food Sci. 2019 Mar;84(3):687-694. doi: 10.1111/1750-3841.14454. Epub 2019 Feb 4.

Abstract

It has been reported that estrogen deficiency in female disrupts systemic endocrinologic regulatory mechanisms, finally leading to osteoporotic condition. Estrogen deficiency also down-regulates brain functions due to its deficits of its original roles in a number of neurological events. Therefore, it is necessary to find alternative materials that can prevent osteoporotic condition and maintain normal brain functions to correct such hormone deficiency. In the present study, we found that novel compounds originated from larvae of Tenebrio molitor (TM) possessed anti-osteoporotic effect. They could also prevent abnormal progressive brain function by deaccelerating enhanced HPA-axis negative feedback while maintaining neurogenesis in hippocampus. We daily administered TM to ovariectomized (OVX) ddY mice for 4 weeks and then performed histological and hormonal evaluations for its anti-osteoporotic effects. In addition, we investigated glucocorticoid receptor (GR) expression and neuroblast expression (DCX) in the hippocampal dentate gyrus morphologically by immunohistochemistry analysis. According to our results, TM has anti-osteoporotic effects. It also tends to bring interfered brain environment back to normal condition. These results suggest that TM might have anti-osteoporosis effect and enhancing effects on enrichment of environment in brain by being antidestroyed hormonal deficiency simultaneously. This is the first study to report that TM can be used as source of bioactive substance to prevent decreased neurogenesis and impaired HPA axis driven by high GR expression in the hippocampus in hormonal deficient female animals. PRACTICAL APPLICATION: Anti-osteoporosis effect and stress resistance due to improved brain function caused by the ingestion of Tenebrio molitor extract were observed in postmenopausal women. T. molitor is available as a nutritional supplement for bone and brain health, which menopausal women need most.

Keywords: Tenebrio molitor; glucocorticoid receptor; hypothalamo-pituitary-adrenal axis; neuroblast; osteoporosis.

MeSH terms

  • Administration, Oral
  • Animals
  • Dietary Supplements
  • Doublecortin Protein
  • Estrogens / metabolism*
  • Female
  • Gene Expression Regulation / drug effects*
  • Hippocampus / drug effects*
  • Larva
  • Mice
  • Ovariectomy
  • Receptors, Glucocorticoid / antagonists & inhibitors*
  • Tenebrio / chemistry*

Substances

  • Dcx protein, mouse
  • Doublecortin Protein
  • Estrogens
  • Receptors, Glucocorticoid