Differentiation-linked changes in the biosynthesis and turnover of sphingomyelins in rat male germ cells: Genes involved and effects of testosterone.
J Biol Chem
; 299(4): 103058, 2023 04.
Article
em En
| MEDLINE
| ID: mdl-36841478
ABSTRACT
In rodents, sphingomyelins (SMs) species with very-long-chain polyunsaturated fatty acid (VLCPUFA) are required for normal spermatogenesis. Data on the expression of enzymes with roles in their biosynthesis and turnover during germ cell differentiation and on possible effects on such expression of testosterone (Tes), known to promote this biological process, were lacking. Here we quantified, in isolated pachytene spermatocytes (PtS), round spermatids (RS), and later spermatids (LS), the mRNA levels from genes encoding ceramide (Cer), glucosylceramide (GlcCer), and SM synthases (Cers3, Gcs, Sms1, and Sms2) and sphingomyelinases (aSmase, nSmase) and assessed products of their activity in cells in culture using nitrobenzoxadiazole (NBD)-labeled substrates and [3H]palmitate as precursor. Transcript levels from Cers3 and Gcs were maximal in PtS. While mRNA levels from Sms1 increased with differentiation in the direction PtSâRSâLS, those from Sms2 increased between PtS and RS but decreased in LS. In turn, the nSmase transcript increased in the PtSâRSâLS order. During incubations with NBD-Cer, spermatocytes produced more GlcCer and SM than did spermatids. In total germ cells cultured for up to 25 h with NBD-SM, not only abundant NBD-Cer but also NBD-GlcCer were formed, demonstrating SMâCer turnover and Cer recycling. After 20 h with [3H]palmitate, PtS produced [3H]SM and RS formed [3H]SM and [3H]Cer, all containing VLCPUFA, and Tes increased their labeling. In total germ cells, Tes augmented in 5 h the expression of genes with roles in VLCPUFA synthesis, decreased the mRNA from Sms2, and increased that from nSmase. Thus, Tes enhanced or accelerated the metabolic changes occurring to VLCPUFA-SM during germ cell differentiation.
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Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Espermatogênese
/
Espermatozoides
/
Esfingomielinas
/
Testosterona
Limite:
Animals
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Argentina