Growth Factors ($26-$50)

Growth factors are a class of signaling proteins and peptides that regulate cell proliferation, differentiation, and survival. Well-studied examples include insulin-like growth factor 1 (IGF-1), fibroblast growth factors (FGFs), epidermal growth factor (EGF), platelet-derived growth factor (PDGF), and nerve growth factor (NGF).

In research, growth factors are essential tools for cell culture, regenerative biology, developmental studies, and cancer research. They are typically used at low concentrations to stimulate specific cellular responses in vitro. All growth factor products from Function Dose are intended for laboratory research use only.

Insulin-like growth factor 1 (IGF-1) is a 70-amino-acid peptide with significant structural similarity to insulin. It is one of the most-studied growth factors in research and is a central player in studies of cell proliferation, differentiation, metabolism, and tissue growth. IGF-1 acts through its own receptor (IGF-1R), which shares downstream signaling components with the insulin receptor.

In the laboratory, IGF-1 is used as a reference ligand in receptor-binding studies, as a supplement in cell culture media for certain cell lines, and as a model peptide in studies of the PI3K/AKT/mTOR signaling pathway. IGF-1 products from Function Dose are supplied for these kinds of research applications only.

Peptide hormones — such as insulin, glucagon, and growth hormone — are typically produced by specialized endocrine glands and act on distant target tissues as part of systemic regulation. Growth factors are usually produced by a wider variety of cell types and tend to act in a more local manner, through autocrine or paracrine signaling on nearby cells.

Another difference lies in their biological roles: peptide hormones are generally studied in the context of metabolic and endocrine regulation, while growth factors are more commonly studied in the context of development, extracellular-matrix remodeling, and proliferation. In practice, the categories overlap, especially for molecules like IGF-1 that behave in both ways.