Flavonoids from Triticum aestivum inhibit adipogenesis in 3T3-L1 cells by upregulating the insig pathway.
The present study aimed to compare the potential anti-adipogenic effects and underlying mechanisms of the luteolin, isoscoparin and isoorientin flavonoids, purified from Triticum aestivum sprout (TA) in 3T3-L1 cells. The cells were treated with different concentrations of flavonoids for 8 days and the lipid accumulation was assessed using Oil-Red-O staining. The expression levels of the transcription factors and the genes involved in adipogenesis in the cells were assessed by reverse transcription-quantitative polymerase chain reaction and western blotting. The results demonstrated that 10 μM luteolin, isoscoparin or isoorientin inhibited lipid deposition in the cells by 74, 63 and 65%, respectively. The flavonoids also significantly inhibited the transcriptional regulators of adipogenesis, including peroxisome proliferator-activated receptor-γ, CAAT/enhancer binding protein-α and sterol regulatory element binding protein (SREBP)-1c, compared with the control cells. Similarly, there was a significant downregulation of the adipocyte specific markers associated with lipid metabolism, including activating protein-2, fatty acid synthase, hormone-sensitive lipase and lipoprotein lipase, in the flavonoid treated cells. Notably, the cells treated with the flavonoids demonstrated increased expression levels of the insulin-induced genes, insig-1 and insig-2, which may have inhibited the activation of the adipogenic transcription factor, SREBP, eventually leading to the inhibition of adipogenesis. Taken together, these results revealed that the flavonoids from TA possessed an inhibitory effect on adipogenesis through downregulation of adipogenic transcription factors and genes associated with lipid metabolism, and the upregulation of insig 1 and 2, suggesting that the flavonoids from TA may be potential therapeutic agents for the prevention and treatment of obesity.
Department of Oriental Pharmacy, College of Pharmacy and Wonkwang‑Oriental Medicines Research Institute, Wonkwang University, Iksan, Jeonbuk 570‑749, Republic of Korea.
Barun
B
Poudel
Department of Immunology and Institute of Medical Sciences, Medical School, Chonbuk National University, Jeonju, Jeonbuk 561‑756, Republic of Korea.
Sarmila
S
Nepali
Department of Oriental Pharmacy, College of Pharmacy and Wonkwang‑Oriental Medicines Research Institute, Wonkwang University, Iksan, Jeonbuk 570‑749, Republic of Korea.
Mingjie
M
Xin
Department of Immunology and Institute of Medical Sciences, Medical School, Chonbuk National University, Jeonju, Jeonbuk 561‑756, Republic of Korea.
Hyeon-Hui
HH
Ki
Department of Pharmacognosy, College of Pharmacy, Chungnam National University, Daejeon 305‑764, Republic of Korea.
Young-Ho
YH
Kim
Department of Immunology and Institute of Medical Sciences, Medical School, Chonbuk National University, Jeonju, Jeonbuk 561‑756, Republic of Korea.
Dae-Ki
DK
Kim
Department of Oriental Pharmacy, College of Pharmacy and Wonkwang‑Oriental Medicines Research Institute, Wonkwang University, Iksan, Jeonbuk 570‑749, Republic of Korea.
Young-Mi
YM
Lee
D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D050156:Adipogenesis / Q000187:drug effects; D000818:Animals; D022762:CCAAT-Enhancer-Binding Proteins / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation; D004224:Diterpenes / Q000302:isolation & purification / Q000494:pharmacology*; D064429:Fatty Acid Synthases / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D008071:Lipoprotein Lipase / Q000235:genetics / Q000378:metabolism; D047311:Luteolin / Q000302:isolation & purification / Q000494:pharmacology*; D008565:Membrane Proteins / Q000819:agonists* / Q000235:genetics / Q000378:metabolism; D051379:Mice; D047495:PPAR gamma / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D002787:Sterol Esterase / Q000235:genetics / Q000378:metabolism; D051780:Sterol Regulatory Element Binding Protein 1 / Q000235:genetics / Q000378:metabolism; D014908:Triticum / Q000737:chemistry*
D022762:CCAAT-Enhancer-Binding Proteins; C530718:CEBPA protein, mouse; D004224:Diterpenes; C506119:Insig1 protein, mouse; C506120:Insig2 protein, mouse; D008565:Membrane Proteins; D047495:PPAR gamma; C497388:Srebf1 protein, mouse; D051780:Sterol Regulatory Element Binding Protein 1; C057912:homoorientin; D064429:Fatty Acid Synthases; D002787:Sterol Esterase; D008071:Lipoprotein Lipase; D047311:Luteolin