Expression Of IGF1 In Mouse First Hair Follicle Growth Cycle And It’s Effects On Alpaca Melanogenesis

The matrix-epithelium between the dermal papilla and the hair matrix regulates the development and proliferation of hair follicle cells during the follicular growth cycle.Multifunctional cell regulatory factor-insulin-like growth factor-1(IGF1)is one of the members of the signal pathway,and hair follicle growth cycle and melanin synthesis has a great relevance.In order to investigate whether IGF1 is associated with hair follicle growth cycle and melanogenesis,the following tests are conducted in this paper.The results are as follows:1 IGF1 and IGF1R genes in the first hair follicle growth cycle of mice were analyzed by immunohistochemical method.The results showed that IGF1 was mainly distributed in the epidermis of mice,while the immunoreactive distribution of IGF1R was in the hair follicles of mice,Both the root sheath and the hairy nipples were distributed.2 The transcription level and protein expression of IGF1 and IGF1R genes in the skin of the first hair follicle growth cycle were analyzed by fluorescence quantitative PCR and Western blotting.The results showed that IGF 1 had the lowest relative expression in IGF1,The highest expression level in the degradation period,and decreased the expression level in the resting period.(P<0.01).The relative expression of IGF1R in the skin was the highest in the growing period,the lowest in the degenerated phase,and the expression of IGF1R in the resting phase and the resting stage The amount has increased.Compared with the initial stage of growth,the expression of IGF1R in the degeneration and quiescent phase was significantly different(P<0.01).3 iCELLigence real-time cell analyzer was used to detect the effect of IGF1 on the proliferation of alpacas melanocytes.The results showed that melanin could continue to proliferate after 72 h in the medium with IGF1 concentration of 0 ng/mL and 10ng/mL.The IGF 1 concentration was At the time of 5 ng/mL,the proliferation of melanocytes reached the peak at about 50 h.When the concentration of IGF1 was 20 ng/mL and 40 ng/mL,the proliferation of melanocytes reached the highest value in about 60 h.4 The expression of cAMP in mycelium melanin cells was detected by ELISA.The results showed that the expression of cAMP was increased by 1.138%at 5 ng/ml,10 ng/ml,20 ng/ml and 40 ng/ml IGF1(P<0.01),but not significant at 20 ng/ml and 40 ng/ml.The difference was not significant(P<0.01),but there was no significant difference between the two groups(P<0.01).5 The transcription level and protein expression of melanin-related genes in alpaca melanocytes with different concentrations of IGF1 were analyzed by fluorescence quantitative PCR and Western blotting.The results showed that the MITF,TYR and TYRP2 genes increased by 2.672 fold changes,1.924 fold changes and 2.869 fold changes respectively when the concentration of IGF1 was 10ng/ml(P<0.01).The MITF,TYR and TYRP2 genes were expressed in protein The level increased by 1.175 fold changes,1.507 fold changes,1.431 fold changes.6 The effect of IGF 1 on melanin production in alpaca melanocytes was detected by microplate reader.The results showed that compared with the control group(0 ng/ml),we added 5 ng/ml,10 ng/ml,20 ng/ml,40 ng/ml Concentration of IGF1 culture conditions,the melanin content increased by 1.626 fold changes,2.305 fold changes,1.659 fold changes,1.566 fold changes.The yield of melanin in the experimental group increased with the increase of 10 ng/ml IGF1(P<0.01).The results suggest that the differential expression of IGF1 in the first follicular growth cycle of mouse skin may be involved in the formation of melanin during the transformation of each stage of the follicle growth cycle.The amount of IGF1 can stimulate the proliferation of alpaca melanocytes and regulate the expression of cAMP in the cells,and regulate the transcription and protein expression of MITF,TYR and TYRP2 genes related to melanogenesis,and affect the formation of melanin.