miR-200b-3p inhibits adipose browning by targeting Prdm16

Area of Science:

• Metabolic Regulation
• Adipose Tissue Biology
• Molecular Endocrinology

Background:

• Obesity pathogenesis is complex, involving white adipose tissue (WAT) dysfunction.
• The role of microRNA miR-200b-3p in obesity and adipocyte browning is largely unknown.
• Understanding miR-200b-3p's function is crucial for developing novel obesity therapeutics.

Purpose of the Study:

• To investigate the functional role of miR-200b-3p in white adipose browning.
• To elucidate the molecular mechanisms underlying miR-200b-3p's effects on adipocytes.
• To assess the therapeutic potential of modulating miR-200b-3p in diet-induced obesity.

Main Methods:

• In vitro studies using C3H10T1/2 and 3T3-L1 cell lines with miR-200b-3p mimic/antisense.
• In vivo studies involving lentiviral injection into mouse inguinal white adipose tissue (iWAT).
• Analysis of gene/protein expression, body/tissue weight, glycolipid metabolism, and insulin resistance.

Main Results:

• miR-200b-3p overexpression impaired white adipose browning; inhibition promoted it.
• Mice with miR-200b-3p overexpression exhibited insulin resistance and metabolic dysfunction under high-fat diet (HFD).
• Inhibition of miR-200b-3p in iWAT protected against HFD-induced insulin resistance.
• miR-200b-3p directly targets Prdm16 expression via Smad and p38 MAPK pathways.

Conclusions:

• miR-200b-3p acts as a negative regulator of white adipose browning.
• Targeting miR-200b-3p offers a potential therapeutic avenue for obesity and associated metabolic diseases.
• Prdm16 is a key downstream target mediating miR-200b-3p's effects on adipocytes.