Table 1 In vitro studies about the influence of soybean isoflavone on muscle
From: Soybean isoflavones potentially prevent sarcopenia: a systematic review
References | Cell lines used in research | Type of soybean or isoflavones | Model of test | Results | Discussion |
|---|---|---|---|---|---|
Jones et al. [31] | Rat L6 myogenic cell lines | Genistein, daidzein, glycitein | Experiments examined cell proliferation and cell protein synthesis stimulation or inhibition The media for cell proliferation experiment consisted of DMEM with FBS supplemetned with insulin, estradiol, genistein, daidzein and glycitein, at 0, 0.04, 0.08, 0.16, 0.31, 0.63, 1.25, 5, 10, or 20 uM concentration The media for cell protein synthesis consisted of DMEM with 2% FBS alone or supplemented with 1uM insulin, 1 uM estradiol, 1 uM genistein, 1 uM daidzein, 1 uM glycitein, or 0.1 uM dexamethasone | Genistein and estradiol inhibit cellular proliferation at a concentration of 5uM and greater Daidzein and glycitein showed no significant difference compared with the control Genistein, daidzein, and glycitein slightly stimulated the protein synthesis, but there were no significant effects | Soy isoflavones may potentially modulate growth and development in humans and animals who consume soy-based products |
Hirasaka et al. [28] | TNF-α treated atrophied C2C12 myoblastic cell | Genistein, daidzein | TNF-α (10 ng/mL) treated atrophied C2C12 myoblastic cells were transfected with pGL3-MuRF1 promoter and pRL-TK and cells were treated with 100 uM of isoflavones (genistein and daidzein) | Genistein and daidzein blocked TNF-α induced myotube atrophy | TNF-α treatment resulted in a decreased myotube thickness and upregulated MuRF1 promoter activity Inhibitory effect of Isoflavones (genistein and daidzein) in upregulated MuRF1 promotor blocked TNF-α induced myotube atrophy |
Saneyasu et al. [32] | C2C12 myoblasts | Soyaflavone RS extract (SRE), Soybean meal extract (SME), Soybean-germ protein extract (SGE) | Soybean meal: defatted soybean, protein content about 45% Soybean-germ protein: protein content about 65% Soyaflavone RS: Roasted soybean-germ powder, protein content about 40% C2C12 cells were treated with SRE, SME, SGE at 1Â mg/ml as protein concentration. And gene expressions of MyH7, MyH2, MyH1, MyH4 were measured by PCR | SRE upregulated MyH7 and downregulated MyH4 SME upregulated Myh7 and downregulated Myh4 and Myh1 SGE upregulated Myh7 | The soybean protein cause the increase of Myh7 which is slow-type myosin heavy chain |
Zheng et al. [33] | C2C12 myotubes | Soy extract (SoyEx) | SoyEx: 5.3 mg/g genistein, 10.4 mg/g daidzein, 3.2 mg/g glycitein C2C12 Myotubes were incubated for 48 h in the presence of SoyEx (0.0005–50 μg/mL), E2 (1 or 10 nM), antiestrogen ZK191703 (1 μM), AR antagonist DHT (1 μM), flutamide (1 μM), genistein (0.001 μM), daidzein (0.0021 μM), glycitein (0.0006 μM), or control (0.1% DMSO only) The diameter of C2C12 myotubes, IGF-1 mRNA expression, IGF-1R mRNA expression, and MuRF1 mRNA expression was measured | The effect of 48 h SyoEx treatment significantly increased myotube diameter at the concentration of 0.05 ug/mL The increased diameter induced by the treatment of either E2 or SoyEx for 48 h was antagonized by an antiestrogen ZK191703 IGF-1R expression was increased by E2, SoyEx, and genistein in C2C12 myotubes | SoyEx increases the diameter of C2C12 myotubes Isoflavone aglycones from SoyEx induce anabolic effects on C2C12 myotubes by binding to ER and increasing IGF-1. Among the tested aglycones, genistein seems to have the strongest anabolic bioactivity |