The variable expression of lectin-like oxidized low-density lipoprotein receptor (LOX-1) and signs of autophagy and apoptosis in freshly harvested human granulosa cells depend on gonadotropin dose, age, and body weight

Objective: To extend our recent observations on lectin-like oxidized low-density lipoprotein receptor (LOX-1) expression in human granulosa cell cultures with freshly harvested granulosa cells. Design: Clinical research. Setting: Institute of Anatomy and Clinic for Reproductive Medicine. Patient(s): Women undergoing IVF therapy were classified by total FSH dose, age, and body mass index. Main Outcome Measure(s): Purified granulosa cells were studied by Western blot and morphology for the presence of LOX-1, microtubule-associated light-chain protein 3 (LC3) and autophagosomes, which are both autophagic markers, cleaved caspase-3 for apoptosis, and apoptosis-inducing factor (AIF) for caspase-independent apoptosis. Intervention(s): None. Results: Active LOX-1 was found in all samples, being at its maximum in the younger obese group with a total FSH dose < 2,000 IU. The LC3 II/LC3 I ratio, indicative of reparative autophagy, was at its maximum in younger normal-weight patients and increased under total FSH dose > 2,000 IU. Autophagosomes in ultrathin sections were indicative of reparative autophagy. Cleaved caspase-3 was absent in all groups. The apoptotic AIF form was up-regulated in older patients. Unpurified granulosa cells consisted of similar to 20% dead cells in the younger normal-weight group compared with up to 50% in the older obese group. Conclusion(s): The regulation of LOX-1 and of cell death in granulosa cells depends on oxidative stress. It becomes excessive during aging and obesity, because the power of reparative autophagy fades and antioxidant efficiency declines. (Fertil Steril (R) 2010; 93: 2706-15. (C) 2010 by American Society for Reproductive Medicine.)