Protective effects of menthol against olanzapine-induced metabolic alterations in female mice

Eur J Pharmacol. 2024 Nov 15:983:177010. doi: 10.1016/j.ejphar.2024.177010. Epub 2024 Sep 18.

Abstract

Aim: Metabolic comorbidities such as obesity type 2 diabetes, insulin resistance, glucose intolerance, dyslipidemia are the major contributors for lower life expectancy and reduced patient compliance during antipsychotic therapy in patients with severe mental illnesses such as schizophrenia, bipolar disorder, and depression. TRPM8 activation by menthol is also reported to alleviate high fat diet-induced obesity in mice. Additionally, this TRPM8 activation leads to increase in gene expression of thermogenic genes in white adipocytes and dietary menthol was found to increase browning of WAT along with improved glucose utilization. Therefore, we aimed to evaluate the plausible role of TRPM8 channels in olanzapine-induced metabolic alterations in female balb/c mice.

Methods: 6 weeks olanzapine (6 mg kg-1, per oral) model was used in female balb/c mice. Pharmacological manipulation of TRPM8 channel was done using menthol and N-(3-aminopropyl)-2-[(3-methylphenyl)methoxy]-N-(2-thienylmethyl)-benzamide (AMTB), the agonist and antagonist respectively.

Key results: Menthol co-treatment for six weeks prevented olanzapine-induced metabolic alterations such as weight gain, increased food intake, decreased energy expenditure, adiposity, liver lipid accumulation, systemic inflammation and insulin resistance. Although no significant change in TRPM8 mRNA expression was found in the hypothalamus, however, some of the protective effects of menthol were absent in presence of AMTB indicating possible involvement of TRPM8 channels.

Conclusion: Our results suggest possible therapeutic implications of menthol in the management of antipsychotic-induced weight gain and other metabolic alterations.

Keywords: AMTB; Antipsychotics; Metabolic syndrome; Olanzapine; TRPM8 channels; menthol.

MeSH terms

  • Adiposity / drug effects
  • Animals
  • Antipsychotic Agents / adverse effects
  • Antipsychotic Agents / pharmacology
  • Eating / drug effects
  • Energy Metabolism / drug effects
  • Female
  • Insulin Resistance*
  • Liver / drug effects
  • Liver / metabolism
  • Menthol* / pharmacology
  • Mice
  • Mice, Inbred BALB C*
  • Obesity / chemically induced
  • Obesity / drug therapy
  • Obesity / metabolism
  • Olanzapine* / adverse effects
  • Olanzapine* / pharmacology
  • TRPM Cation Channels* / genetics
  • TRPM Cation Channels* / metabolism
  • Weight Gain / drug effects

Substances

  • Olanzapine
  • Menthol
  • TRPM Cation Channels
  • TRPM8 protein, mouse
  • Antipsychotic Agents