Physiologically based microenvironment for in vitro neural differentiation of adipose-derived stem cells

Table 1 Functions of growth factors on neural induction of adipose stem cells

Growth factors	Profile	Physiological activity	Effect on ASCs	Remarks
EGF	Small polypeptide of 53 amino acid residues and a molecular mass of approximately 6000 daltons[57]	Development of the oral cavity, lungs, gastrointestinal tract, epidermis, derma, eyelids and central nervous system[56]	Promotion of proliferation with delays of senescence and insurance of differentiation potency[55]	EGF and bFGF co-administration limits ASCs differentiation abilities by inducing ASCs into an ectodermal lineage rather than the mesodermal one[53]
bFGF	Non-glycosylated polypeptide of 18 kDa and 155 amino acid in length (heparin-binding growth factor family)	Stimulator of tissue repair and cellular viability released from an injured extracellular matrix[64]	Enhancement of proliferation, differentiation and hepatocyte growth factor expression ability[58]. Induction of the adipogenic[59] and chondrogenic[60] potential, with inhibition of osteogenic differentiation[61]
PDGF	Dimeric glycoprotein	Potent mitogen for cell of mesodermal lineage and stimulator of tissue repair released from activated platelets on bleeding[65]	Supporting of cell proliferation in vitro: It increases ASCs yield. Promotion of neural differentiation in an antioxidant microenvironment[48]	Receptor-β signalling is involved primarily in ASCs stimulation[62]. ASCs stimulation with autologous platelet-rich plasma reduces the cost of differentiation[48]

EGF: Epidermal growth factor; bEGF: Basic fibroblast growth factor; PDGF: Platelet-derived growth factor; ASCs: Adipose stem cells.