Production of Lysophosphatidic Acids by Lysophospholipase D in Human Follicular Fluids of In Vitro Fertilization Patients1

Abstract

Lysophosphatidic acids (LPAs) are known to be normal constituents of mammalian serum, and they mimic some biological effects of the serum. We previously reported that lysophospholipase D (LPLD) was involved in the accumulation of LPAs in incubated rat plasma and serum. In this study we detected, by gas-liquid chromatography, various molecular species of LPA in follicular fluids collected from women programmed for in vitro fertilization. When the follicular fluid was incubated at 37 degrees C for 48 h, persistent increases in the amounts of LPAs were observed concomitant with decreases in the amounts of the corresponding lysophosphatidylcholines (LPCs), although the concentrations of saturated LPCs increased in the first 6 h of incubation. These results suggest that human follicular fluid has LPLD activity, and this was confirmed by experiments with follicular fluids mixed with an exogenous radioactive LPC. The LPLD showed preference for unsaturated over saturated LPCs, similar to plasma LPLD, indicating that it originated from the circulation.

Differential effects of lysolipids on steroid synthesis in cells expressing endogenous LPA2 receptor

“…RNA purification kit was from Peqlab (Erlangen, Germany). SuperScript II reverse transcriptase, 100 bp size ladder standard, and low DNA mass ladder standard were from Invitrogen (Karlsruhe, Germany); dNTP, Oligo(dT) [12][13][14][15][16][17][18] , and [ 3 H]choline chloride were from Amersham Pharmacia Biotech (Freiburg, Germany); BioTherm polymerase was from GeneCraft (Münster, Germany), QiaQuick gel extraction kit from Qiagen (Hilden, Germany), Abi Prism dye terminator sequencing ready reaction kit from Perkin Elmer (Branchburg, NJ), and oligonucleotides from MWG Biotech (Ebersberg, Germany). [ 14 C]acetic acid sodium salt was from BioTrend (Cologne, Germany), and [U 14 C]serine was from ICN Pharmaceuticals, Inc. (Irvine, CA).…”

“…To estimate RNA integrity, an aliquot was electrophoretically separated on 1.5% agarose gel and visualized by staining with ethidium bromide. Following the manufacturer's instructions, first-strand cDNA was synthesized from 3 g total RNA using SuperScript II reverse transcriptase, 0.5 mM each of deoxyribonucleoside triphosphate and 500 ng oligo(dT) [12][13][14][15][16][17][18] as primer. After comple-tion of the reaction, 80 l of water was added to yield a final volume of 100 l. Two microliters of cDNA from theca, granulosa, luteal cells, and controls was used as template for PCR amplification of LPA receptors, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a valuable marker, as a housekeeping gene in ovarian cells (31,32).…”

“…In recent years, much attention has been focused on the role of LPA in tumor biology (5,15), overshadowing studies linking this bioactive lipid to reproductive physiology (16)(17)(18). We showed previously that LPA elicits dramatic morphoregulatory effects on cultured luteal cells, steroidproducing cells originating from the ovarian corpus luteum (19).…”

L’acide lysophosphatidique : un phospholipide « bioactif »

“…Le LPA est présent en forte concentration dans les ascites prélevées chez des patientes atteintes de cancer ovarien [8]. Le LPA est éga-lement retrouvé en abondance dans le liquide folliculaire, associé aux lipoprotéines [9,10]. Notre groupe a trouvé du LPA dans le milieu interstitiel du tissu adipeux souscutané humain prélevé par microdialyse, avec comme origine cellulaire, les adipocytes [11].…”

Quantitative analysis of lysophosphatidic acid by time-of-flight mass spectrometry using a phosphate-capture molecule

“…Because of its growth factor-like activity, LPA is considered to play a role in the wound-healing process (13,14). Furthermore, evidence is accumulating that LPA present in human follicular fluid (15) or hen egg white (16) plays an essential role in embryonic development or egg transport (17). Also of importance are findings that LPA accumulates at high concentrations in plasma from patients with ovarian cancer (10,11) and that LPA in ascitic fluid from patients with ovarian cancer may act as a mitogen to ovarian carcinoma cells (18,19).…”