Hair follicle development and related gene and protein expression of skins in Rex rabbits during the first 8 weeks of life

OBJECTIVE: We aimed to observe hair follicle (HF) development in the dorsal skin and elucidate the expression patterns of genes and proteins related to skin and HF development in Rex rabbits from birth to 8 weeks of age. METHODS: Whole-skin samples were obtained from the backs of Rex rabbits at 0, 2, 4, 6, and 8 weeks of age, the morphological development of primary and secondary HFs was observed, and the gene transcript levels of insulin-like growth factor-I (IGF-I), epidermal growth factor (EGF), bone morphogenetic protein 2 (BMP2), transforming growth factor β-1, 2, and 3 (TGFβ-1, TGFβ-2, and TGFβ-3) were examined using quantitative real-time polymerase chain reaction (PCR). Additionally, Wnt family member 10b (Wnt10b) and β-Catenin gene and protein expression were examined by quantitative real-time PCR and western blot, respectively. RESULTS: The results showed significant changes in the differentiation of primary and secondary HFs in Rex rabbits during their first 8 weeks of life. The IGF-I, EGF, TGFβ-2, and TGFβ-3 transcript levels in the rabbits were significantly lower at 2 weeks of age than at birth and gradually increased thereafter, while the BMP2 and TGFβ-1 transcript levels at 2 weeks of age were significantly higher than those at birth and gradually decreased thereafter. β-Catenin gene expression was also significantly affected by age, while the Wnt10b transcript level was not. However, the Wnt10b and β-catenin protein expression levels were the lowest at 2 and 4 weeks of age. CONCLUSION: Our data showed that a series of changes in HFs in dorsal skin occurred during the first 8 weeks. Many genes, such as IGF-I, EGF, BMP2, TGFβ-1, TGFβ-2, TGFβ-3, and β-Catenin, participated in this process, and the related proteins Wnt10b and β-Catenin in skin were also affected by age.