Causes and consequences of obesity: epigenetics or hypokinesis?

Inula britannica Inhibits Adipogenesis of 3T3-L1 Preadipocytes via Modulation of Mitotic Clonal Expansion Involving ERK 1/2 and Akt Signaling Pathways

The flower of Inula britannica contains various phenolic compounds with prophylactic properties. This study aimed to determine the anti-adipogenic effect of an I. britannica flower aqueous extract (IAE) and its underlying mechanisms in the 3T3-L1 preadipocytes and to identify the phenolic compounds in the extract. Treatment with IAE inhibited the adipogenesis by showing a dose-dependent suppressed intracellular lipid accumulation and mitigated expression levels of lipogenesis- and adipogenesis-associated biomarkers including transcription factors. IAE exerted an anti-adipogenic effect through the modulation of the early phases of adipogenesis including mitotic clonal expansion (MCE). Treatment with IAE inhibited MCE by arresting the cell cycle at the G0/G1 phase and suppressing the activation of MCE-related transcription factors. Furthermore, IAE inhibited adipogenesis by regulating the extracellular signal-regulated kinase 1/2 and Akt signaling pathways. Protocatechuic acid, chlorogenic acid, kaempferol-3-O-glucoside, and 6-methoxyluteolin, which are reported to exhibit anti-adipogenic properties, were detected in IAE. Therefore, modulation of early phases of adipogenesis, especially MCE, is a key mechanism underlying the anti-adipogenic activity of IAE. In summary, the anti-obesity effects of IAE can be attributed to its phenolic compounds, and hence, IAE can be used for the development of anti-obesity products.

Viburnum opulus L. Juice Phenolics Inhibit Mouse 3T3-L1 Cells Adipogenesis and Pancreatic Lipase Activity

Viburnum opulus L. fruit is a rich source of phenolic compounds that may be involved in the prevention of metabolic diseases. The purpose of this study was to determine the effects of Viburnum opulus fresh juice (FJ) and juice purified by solid-phase extraction (PJ) on the adipogenesis process with murine 3T3-L1 preadipocyte cell line and pancreatic lipase activity in triolein emulsion, as well as their phenolic profiles by UPLC/Q-TOF-MS. Decrease of lipids and triacylglycerol accumulation in differentiated 3T3-L1 cells were in concordance with downregulation of the expression of peroxisome proliferator-activated receptor-gamma (PPARγ), CCAAT/enhancer-binding protein alpha (C/EBPβ/α), and sterol regulatory element-binding protein 1c (SREBP-1c). Furthermore, regulation of PPARγ-mediated β-lactamase expression by V. opulus components in reporter gene assay, as well as their binding affinity to ligand-binding domain of PPARγ, were tested. In addition, the levels of enzymes involved in lipid metabolism, like fatty acid synthase (FAS) or acetyl-CoA carboxylase (ACC), were decreased, along with inflammatory cytokines, like tumor necrosis factorα (TNFα), interleukin-6 (Il-6) and leptin. Moreover, FJ and PJ were able to inhibit pancreatic lipase, which potentially could reduce the fat absorption from the intestinal lumen and the storage of body fat in the adipose tissues. Thirty-two phenolic compounds with chlorogenic acid as the dominant compound were identified in PJ which revealed significant biological activity. These data contribute to elucidate V. opulus juice phenolic compounds’ molecular mechanism in adipogenesis regulation in 3T3-L1 cells and dietary fat lipolysis.

Bridging the Science-Practice Gap in Obesity Treatment

The number of putative causes of obesity continues to increase at a rapid rate. As science identifies novel causes of obesity, innovations in the treatment of obesity also evolve. These innovations have important implications for clinical practice; however, a gap exists between research and the clinical application of research. Practical considerations about how to address this gap between research and practice are discussed.