Research Note: Adipogenic differentiation of embryonic fibroblasts of chicken, turkey, duck, and quail in vitro by medium containing chicken serum alone

Abstract

The study of adipogenesis is one of the most important areas for not only regulating meat quality, but production efficiency associated with fat accretion in the poultry species. Current in vitro models for avian adipogenesis require adipogenic inducers including dexamethasone, 3-isobutyl-1-methylxanthine ( IBMX ), fatty acids, or insulin. However, problems still remain in these models for testing/screening potential nutritional, hormonal, and pharmaceutical factors because of interfering/overriding effects of the inducing factors. Therefore, the purpose of this study was to develop a simple in vitro method for avian adipogenesis. In this study, chicken serum ( CS ) and fetal bovine serum ( FBS ) were compared for adipogenic potential using chicken embryonic fibroblasts ( CEF ). Oil-red O staining at 4 d in culture of CEF under CS revealed that lipid droplet formation was increased by CS in a dose-dependent manner (0 to 10%). On the contrary, all concentrations of FBS (0 to 10%) alone did not show lipid droplet formation. In accordance with the morphological data of CEF, mRNA expression of genes involved in adipocyte differentiation/determination, fatty acid uptake, and triacylglycerol ( TAG ) synthesis, were most significantly up-regulated by 10% CS at d 4 compared to 1 or 5% CS. In addition, embryonic cells isolated from quail ( QEF ) at E5, duck ( DEF ) at E6, and turkey ( TEF ) at E6, were tested for adipogenic differentiation by media containing the same concentrations of CS. Similar to the morphological data from CEF, quantitative data of the Oil-red O staining showed that lipid droplet formation in QEF, DEF, and TEF was increased by CS in a dose-dependent manner (0 to 10%). The current study demonstrates that CS alone can induce adipogenesis on embryonic fibroblasts of various poultry species. By providing a new simple in vitro method of avian adipogenesis, diverse nutritional, hormonal, and pharmaceutical factors can be broadly and easily tested for scientific and industrial purposes.

Transdifferentiation of fibroblasts into muscle cells to constitute cultured meat with tunable intramuscular fat deposition

“…It seems that the cells grown in 3D hydrogel showed enhanced lipogenesis compare to the flat surface cultured cells, similar to the myogenic transdifferentiation process in 3D. In addition to the lipogenic induction with fatty acids and insulin (FI), we also validated the use of chicken serum in promoting lipid accumulation as previous reported (Kim et al, 2021). Our results showed that the chicken serum alone could also stimulate fat accumulation effectively (Figure S7D, S7E and S7F).…”

“…The intramuscular fat is a crucial component of meat that can determine its quality attributes, such as taste and flavor. The chicken fibroblasts have been reported to be amenable for lipogenesis through various stimulus, including chicken serum, insulin, fatty acids and retinoic acids (Kim et al, 2021; Kim et al, 2020; Lee et al, 2021). We first attempted different lipogenic stimulations on 2D cultured cells and stained them for Oil Red O to visualize and quantify fat deposition in the fibroblasts.…”

Transdifferentiation of Myoblasts Into Adipocytes by All-Trans-Retinoic Acid in Avian

“…In general, insulin, isobutylmethylxanthine (IBMX), and dexamethasone have been widely used for adipogenic differentiation in a mammal system including 3T3-L1 cells. However, we developed a minimal adipogenic media containing chicken serum alone that can differentiate avian embryonic fibroblasts into adipocytes ( Kim et al, 2021b ). This minimal adipogenic media for avian species can be used to directly test hormonal and nutritional factors without complex interactions of several factors included in so-called adipogenic cocktails.…”

“…The primary myoblasts were cultured in Dulbecco’s modified Eagle’s medium (DMEM, #11965, Gibco) supplemented with 10% fetal bovine serum (FBS, #F4135, Sigma-Aldrich), and 1% antibiotic–antimycotic solution (#15240062, Gibco). To test the potential effect of atRA on adipogenic differentiation of myoblasts, different concentrations of atRA (0 μM, 100 μM, 150 μM, or 200 μM, #R2625, Sigma-Aldrich) were supplemented to the basic adipogenic media, DMEM containing only 10% chicken serum (CS, #C5405, Sigma-Aldrich) ( Kim et al, 2021b ), for 48 h. Due to similar viability of the cells between the two groups, 0 and 100 μM of atRA ( Supplementary Figure S1 ), 100 μM of atRA was mainly used in this study. Myogenic differentiation was induced by 1% horse serum (HS, #16050, Gibco) for 48 h.…”

“…These precursor cells have abilities to be differentiated into myocytes with the expression of myogenic transcriptional factors ( Rosen and MacDougald 2006 ; Rodeheffer et al, 2008 ). Especially, Pparγ has been served as a well-known indicator for adipogenic differentiation in mammals ( Tamori et al, 2002 ; Liang et al, 2016 ) and avian species ( Kim et al, 2020a , Kim et al, 2020b , Kim et al, 2021a , Kim et al, 2021b ; Lee et al, 2021 ). In addition, over-expression or activation of Pparγ can convert myogenic cells to adipocytes ( Hu et al, 1995 ; Teboul et al, 1995 ).…”