Differentiation-related changes in lipid classes with long-chain and very long-chain polyenoic fatty acids in rat spermatogenic cells[S]
- Gerardo M. Oresti*,
- Juan G. Reyes†,
- Jessica M. Luquez*,
- Nelson Osses†,
- Natalia E. Furland* and
- Marta I. Aveldaño1,*
- *Instituto de Investigaciones Bioquímicas de Bahía Blanca, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) y Universidad Nacional del Sur (UNS), Bahía Blanca, Argentina
- †Instituto de Química, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
Abstract
In rat seminiferous tubules (ST), cells that contain polar and neutral lipids with long-chain polyenoic fatty acids (PUFA) and sphingomyelins (SM) and ceramides (Cer) with very long chain (VLC) PUFA of the n-6 series coexist. In this study, pachytene spermatocytes and round spermatids were isolated to determine how these lipids change during spermatogenesis. As the amount per cell of PUFA-rich glycerophospholipids (GPL) decreased with cell size, the 22:5/20:4 ratio increased with cell differentiation. The elovl2 and elovl5 genes, required for 22:5 formation, were expressed (mRNA) in both cell types. Residual bodies- particles with compacted organelles and materials discarded from late spermatids-concentrated cholesterol, 22:5-rich triacylglycerols, and GPL, including plasmalogens and phosphatidylserine. Species of SM and Cer with nonhydroxylated (n-) VLCPUFA (28:4, 30:5, and 32:5) predominated in pachytene spermatocytes, whereas species with the corresponding 2-hydroxy (2-OH) VLCPUFA prevailed in round spermatids. Thus, a dramatic increase in the 2-OH/n-VLCPUFA ratio in SM and Cer was a hallmark of differentiation. A substantial decrease of 2-OH SM occurred between spermatids and mature spermatozoa and 2-OH SM species were collected in residual bodies “en route” to Sertoli cells. Notably, spermatids and spermatozoa gained a significant amount of ceramides devoid of n-VLCPUFA but having 2-OH VLCPUFA as their main fatty acids.
- ceramides
- elongases
- glycerophospholipids
- pachytene spermatocytes
- spermatids
- triacylglycerols
- residual bodies
- sphingomyelins
- very long chain fatty acids
Footnotes
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↵1 To whom correspondence should be addressed. e-mail: avelda{at}criba.edu.ar
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- Abbreviations:
- ADG
- triglyceride with an ether bond
- CE
- cholesterol ester
- Cer
- ceramide
- CGP
- choline glycerophospholipid
- DPG
- diphosphatidylglycerol
- EGP
- ethanolamine glycerophospholipid
- Elovl
- fatty acid elongase
- GC
- gas chromatography
- GPL
- glycerophospholipid
- LPC
- lysophosphatidylcholine
- PI
- phosphatidylinositol
- PL
- phospholipid
- PS
- phosphatidylserine
- PtS
- pachytene spermatocyte
- RB
- residual body
- RS
- round spermatid
- SM
- sphingomyelin
- SPZ
- spermatozoa
- ST
- seminiferous tubule
- TAG
- triacylglycerol
- VLCPUFA
- very long-chain polyunsaturated fatty acid. Please note that n- and 2-OH are used as prefixes to denote nonhydroxy and 2-hydroxy VLCPUFA, respectively.
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This work was supported by funds from Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Agencia Nacional de Promoción de la Ciencia y la Tecnología (ANPCyT), and Universidad Nacional del Sur (UNS), Argentina, and by Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT), Chile.
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↵[S] The online version of this article (available at http://www.jlr.org) contains supplementary data in the form of three figures.
- Received February 25, 2010.
- Revision received July 7, 2010.
- Copyright © 2010 by the American Society for Biochemistry and Molecular Biology, Inc.
