Green tea beneficial effects involve changes in the profile of immune cells in the adipose tissue of obese mice

Eur J Nutr. 2023 Feb;62(1):321-336. doi: 10.1007/s00394-022-02963-3. Epub 2022 Aug 22.

Abstract

Purpose: During obesity, the adipose tissue is usually infiltrated by immune cells which are related to hallmarks of obesity such as systemic inflammation and insulin resistance (IR). Green tea (GT) has been widely studied for its anti-inflammatory actions, including the modulation in the proliferation and activity of immune cells, in addition to preventing cardiovascular and metabolic diseases.

Methods: The aim of the present study was to analyze the population of immune cells present in the subcutaneous and epididymal white adipose tissue (WAT) of mice kept at thermoneutrality (TN) and fed with a high-fat diet (HFD) for 16 weeks, supplemented or not with GT extract (500 mg/kg/12 weeks).

Results: The HFD in association with TN has induced chronic inflammation, and IR in parallel with changes in the profile of immune cells in the subcutaneous and epidydimal WAT, increasing pro-inflammatory cytokines release, inflammatory cells infiltration, and fibrotic aspects in WAT. On the other hand, GT prevented body weight gain, in addition to avoiding IR and inflammation, and the consequent tissue fibrosis, maintaining a lower concentration of cytokines and a profile of immune cells similar to the control mice, preventing the harmful modulations induced by both HFD and TN.

Conclusions: GT beneficial effects in WAT abrogated the deleterious effects triggered by HFD and TN, maintaining all immune cells and fibrotic markers at the same level as in lean mice. These results place WAT immune cells population as a potential target of GT action, also highlighting the positive effects of GT in obese mice housed at TN.

Keywords: Immune cells; Inflammation; Metabolism; Obesity; Polyphenols; Thermoneutrality.

MeSH terms

  • Adipose Tissue / metabolism
  • Adipose Tissue, White / metabolism
  • Animals
  • Cytokines / metabolism
  • Diet, High-Fat / adverse effects
  • Inflammation / metabolism
  • Insulin Resistance*
  • Mice
  • Mice, Inbred C57BL
  • Mice, Obese
  • Obesity / complications
  • Tea* / metabolism

Substances

  • Tea
  • Cytokines