Sorghum (Sorghum bicolor) Extract-Induced Adipogenesis Is Independent of PPARγ Ser273 Phosphorylation in 3T3-L1 Adipocytes

• Published in: Biological & pharmaceutical bulletin 2022/05/01, Vol.45(5), pp.659-663
• Main Authors: Nagaoka, Aozora, Sakurai, Makoto, Kamiie, Katsuyoshi, Masumi, Atsuko
• Format: Article
• Language: English
• Subjects: 3T3-L1 cell; 3T3-L1 Cells; Adipocytes; Adipocytes - metabolism; Adipogenesis; Animals; Dexamethasone; Hypoglycemic Agents - metabolism; Insulin; Lipid metabolism; Mice; peroxisome proliferator-activated receptor γ; Peroxisome proliferator-activated receptors; Phosphorylation; Plant Extracts - metabolism; Plant Extracts - pharmacology; PPAR gamma - metabolism; Preadipocytes; Sorghum; Sorghum - metabolism; Sorghum bicolor; sorghum extract; Troglitazone
• ISSN: 0918-6158; 1347-5215
• DOI: 10.1248/bpb.b22-00087

Previously we showed that the water-soluble fraction of sorghum extract (SE) improves adipogenesis in 3-isobutyl-1-methylxanthine (IBMX)/dexamethasone/insulin (MDI)/thiazolidinedione (TZD)-induced 3T3-L1 preadipocytes but downregulates genes related to peroxisome proliferator-activated receptor γ (PPARγ) and adipogenesis in both MDI- and MDI/TZD-induced 3T3-L1 adipocytes. In this study, we showed that SE treatment altered the accumulation of stained lipids in 3T3-L1 adipocytes induced by MDI/troglitazone (Tro). Immunoblot analyses indicated that SE treatment reduced adipocyte protein 2 (aP2) expression and induced peroxisome proliferator-activated receptor α (PPARα) protein expression in the presence of Tro in 3T3-L1 adipocytes. MDI/Tro treatment, but not MDI treatment, of 3T3-L1 cells induced PPARγ phosphorylation at Ser273. SE downregulated PPARγ expression in MDI-induced 3T3-L1 adipocytes and did not affect its phosphorylation at Ser273 in MDI- and MDI/Tro-induced 3T3-L1 adipocytes. Therefore, SE likely promotes adipogenesis and lipid metabolism in 3T3-L1 preadipocytes by cooperating with Tro independent of PPARγ Ser273 phosphorylation.