Fibroblast growth factor homologous factor 1 stimulates Leydig cell regeneration from stem cells in male rats

Abstract

Fibroblast growth factor homologous factor 1 (FHF1) is an intracellular protein that does not bind to cell surface fibroblast growth factor receptor. Here, we report that FHF1 is abundantly present in Leydig cells with up‐regulation during its development. Adult male Sprague Dawley rats were intraperitoneally injected with 75 mg/kg ethane dimethane sulphonate (EDS) to ablate Leydig cells to initiate their regeneration. Then, rats daily received intratesticular injection of FHF1 (0, 10 and 100 ng/testis) from post‐EDS day 14 for 14 days. FHF1 increased serum testosterone levels without affecting the levels of luteinizing hormone and follicle‐stimulating hormone. FHF1 increased the cell number staining with HSD11B1, a biomarker for Leydig cells at the advanced stage, without affecting the cell number staining with CYP11A1, a biomarker for all Leydig cells. FHF1 did not affect PCNA‐labelling index in Leydig cells. FHF1 increased Leydig cell mRNA ( Lhcgr , Scarb1 , Star , Cyp11a1 , Hsd3b1 , Cyp17a1 , Hsd17b3, Insl3 , Nr5a1 and Hsd11b1 ) and their protein levels in vivo. FHF1 increased preadipocyte biomarker Dlk1 mRNA level and decreased fully differentiated adipocyte biomarker ( Fabp4 and Lpl ) mRNA and their protein levels. In conclusion, FHF1 promotes Leydig cell regeneration from stem cells while inhibiting the differentiation of preadipocyte/stem cells into adipocytes in EDS‐treated testis.

Dehydroepiandrosterone and Its CYP7B1 Metabolite 7α-Hydroxydehydroepiandrosterone Regulates 11β-Hydroxysteroid Dehydrogenase 1 Directions in Rat Leydig Cells

“…The primers for Cyp7b1 were: 5'-GAAGTCCTGCGTGACGAAAT-3' (forward); 5'-CCTCAGAACCTCAAGAATAGCG-3' (reverse); and the size of PCR product is 138 bp. For the internal standard, primers to ribosomal protein S16 (Rps16) were used, as described previously (28).…”

Monocyte Chemoattractant Protein-1 stimulates the differentiation of rat stem and progenitor Leydig cells during regeneration

“…Rats were acclimated in the following conditions: 12 h dark/light cycle, 21-25°C, 55% relative humidity, and ad libitum access to water and food. At the time of experiment, the median weight of rats was 381 g (315 g~450 g) and the median age of rats was 67 d. After 7-d acclimation, each rat was given EDS (75 mg/kg body weight) via intraperitoneal injection [27]. Previous studies demonstrated that a single dose (75 mg/kg) of EDS killed all Leydig cells in the rat testis on the 7th day after EDS and Leydig cells were completely recovered 56 d later [3,9,28].…”

“…Total RNAs were purified from testes and STs using Trizol kit (Invitrogen, Carlsbad, CA) as previously described [27]. RNA concentration measurement, cDNA synthesis and qPCR with SYBR Green qPCR Kit (Roche, Basel, Switzerland) were conducted as previously described [13].…”

“…Western blotting was carried out as previously described [27]. Briefly, the testis or STs were lysed in RIPA lysis buffer (Bocai Biotechnology, China) and homogenized.…”

Stem Cells, Self-Renewal, and Lineage Commitment in the Endocrine System

“…Nevertheless, their depletion in conditions such as ethane dimethanesulfonate is followed by the appearance of new, fully functional adult Leydig cells (254, 255), which are thought to arise from precursors stem cells (254). Very recently, it was shown in male rats that Fgf-homologous factor-1 (Fhf1 or Fgf12), an intracellular protein, is abundant in Leydig cells and that injection of Fhf1 resulted in Leydig cells regeneration from precursor stem cells in rats where Leydig cells were pharmacologically ablated (256).…”