Variability in the components of high-density lipoprotein particles measured in human ovarian follicular fluid: a cross-sectional analysis

Abstract

Objective Assess the variability of follicular fluid (FF) high-density lipoprotein (HDL) particle components. Design FF specimens were collected from two contralateral follicles on the day of oocyte retrieval and analyzed for HDL components. We characterized analytes by age, body mass index (BMI), race and smoking using a cross-sectional design. Biological variability was assessed using two-stage nested analysis of variance. Setting Reproductive health center. Patients One-hundred eighty in vitro fertilization (IVF) patients. Interventions None. Main Outcome Measures Nineteen HDL components including HDL-cholesterol and free (unesterified) and esterified forms, phospholipids, triglycerides, apolipoproteins A-1 and A-2, paraoxonase 1 (PON1) activities, and seven lipophilic vitamins and micronutrients. Results For some analytes, a majority of total measurement variability was attributed to sources between-follicles, suggesting an important role for the integrity of the blood-follicle-barrier and in situ remodeling of plasma derived constituents. For other analytes, variability was mostly attributed to sources between-women, likely indicative of plasma levels. Variability between-follicles decreased with increasing age, differed by BMI and smoking, and generally were lower for Asians and women with diminished ovarian reserve. Conclusions Substantial variability in FF HDL components exist between-follicles among women undergoing IVF, as well as between-women by age, BMI, race, smoking and by infertility diagnosis.

Variability in follicular fluid high density lipoprotein particle components measured in ipsilateral follicles

“…Previously, a similar observation was seen for triglycerides sampled from contralateral follicles (i.e., CV = 22.52 %) [20]. Also similar to the contralateral analyses, CVs exceeded 10 % for all group II HDL analytes, except for cholesteryl linoleate (8.47 %) [20]. The higher CVs for group II HDL analytes compared to group I analytes in our study might be due to their substantially lower mean concentrations compared to group I, yet variance estimates of measured analytes in both groups were similar.…”

“…In our study of HDL particle components measured in ipsilateral follicles, the CVs of most group I HDL analytes were well below 10 %, with the exception of triglycerides (30.35 %). Previously, a similar observation was seen for triglycerides sampled from contralateral follicles (i.e., CV = 22.52 %) [20]. Also similar to the contralateral analyses, CVs exceeded 10 % for all group II HDL analytes, except for cholesteryl linoleate (8.47 %) [20].…”

“…Accordingly, variability between ipsilateral follicles was low relative to variability between women for most of the HDL particle components we measured, suggesting coordinated interfollicular HDL metabolism within ovary. In contrast, previous data for contralateral follicles suggested a larger contribution from extra-ovarian sources for most HDL particle components [20], possibly associated with the mesenteric circulation/blood supply. For example, the RV of phospholipids (0.55 vs. 0.09), ApoA-1 (0.51 vs. 0.10), and ApoA-2 (1.21 vs. 0.10) in the contralateral follicles was substantially higher than those measured in ipsilateral follicles, respectively, implying a greater contribution of between contralateral follicle variability than between ipsilateral follicle variability, possibly due to ovary-specific blood supplies.…”

“…To help to address the abovementioned data gap, Bloom et al recently characterized the biological variability of FF HDL particle components collected from contralateral ovaries [20]. Substantial variability for 19 FF HDL particle components was reported between follicles from contralateral ovaries, as well as between women according to demographic and clinical factors.…”

“…These results underscored the importance of a Bone follicle-one oocyte^design in studies of follicular mechanisms and IVF outcomes. To augment those data, we here made a preliminary characterization of biological variabilities in HDL particle components, using FF collected from ipsilateral follicles, and compared these to our previously reported results for contralateral follicles [20].…”