Oxidized low-density lipoprotein (oxLDL)-induced cell death in dorsal root ganglion cell cultures depends not on the lectin-like oxLDL receptor-1 but on the toll-like receptor-4.

DRG cells have been found to undergo apoptosis and necrosis after oxidized low-density lipoprotein (oxLDL) stimulation in vitro. However, the mechanism of oxLDL-induced DRG cell death is unclear. For this reason, we studied the expression of two potential oxLDL receptors: lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) and toll-like receptor-4 (TLR4) in dorsal root ganglion (DRG) cell cultures from postnatal rats. Cells were cultivated with and without oxLDL. In oxLDL-treated DRG cell cultures, the increase of cleaved caspase-3 protein was observed as a sign of enhanced apoptosis. Untreated and oxLDL-treated DRG cell cultures expressed LOX-1 and TLR4 at similar levels. The LOX-1 expression remained unchanged after receptor blockade. However, the inhibition of LOX-1 caused a significant increase of cleaved caspase-3 and a decrease of TLR4 levels. The TLR4-inhibited DRG cell cultures lacked changes in LOX-1 expression for all experimental groups. The inhibition of TLR4 caused activation of jun N-terminal kinase (JNK) and a significant decrease of cleaved caspase-3 but did not change the TLR4 level. We conclude that LOX-1 and TLR4 are expressed in cultivated rat DRG cells and that the oxLDL-induced cell death in DRG cell cultures does not depend on the LOX-1 but on the TLR4.

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 approximately 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.

Procarbazine-free OEPA-COPDAC chemotherapy in boys and standard OPPA-COPP in girls have comparable effectiveness in pediatric Hodgkin's lymphoma: the GPOH-HD-2002 study.

PURPOSE: Vincristine, etoposide, prednisone, and doxorubicin (OEPA)-cyclophosphamide, vincristine, prednisone, and dacarbazine (COPDAC) is derived from standard vincristine, procarbazine, prednisone, and doxorubicin (OPPA)-cyclophosphamide, vincristine, procarbazine, and prednisone (COPP) chemotherapy by replacing procarbazine with etoposide and dacarbazine for a potentially less gonadotoxic regimen for boys with Hodgkin's lymphoma (HL). PATIENTS AND METHODS: Five hundred seventy-three pediatric patients with classical HL were enrolled onto the German Society of Pediatric Oncology and Hematology-Hodgkin's Disease (GPOH-HD) -2002 study between November 2002 and December 2005. Boys received two courses of OEPA and girls received two courses of OPPA for induction. Treatment group (TG) -2 (intermediate stages) and TG-3 (advanced stages) patients received further two or four cycles COPP (girls) or COPDAC (boys), respectively. After chemotherapy all patients received involved-field irradiation with 19.8 Gy, except for patients with early-stage disease (TG-1) in complete remission. RESULTS: Five hundred seventy-three patients (287 males and 286 females) were less than 18 years old and fulfilled all inclusion criteria; 195 patients (34.0%) were allocated to TG-1, 139 (24.3%) were allocated to TG-2, and 239 (41.7%) were allocated to TG-3. Toxicity of OEPA-COPDAC was tolerable overall. Hematotoxicity was more pronounced with OEPA than OPPA, whereas it was less pronounced with COPDAC compared with COPP. The median observation time was 58.6 months. Overall survival and event-free survival (EFS) rates (+/- SE) at 5 years were 97.4% +/- 0.7% and 89.0% +/- 1.4%, respectively. In TG-1, overall EFS was 92.0% +/- 2.0%. EFS of patients without irradiation (93.2% +/- 3.3%) was similar to that of irradiated patients (91.7% +/- 2.5%), confirming results of the previous GPOH-HD-95 study. In TG-2+3, EFS did not significantly differ between boys and girls (90.2% +/- 2.3 v 84.7% +/- 2.7, respectively; P = .12). CONCLUSION: In TG-2+3, results in boys and girls are superimposable. OPPA-COPP and OEPA-COPDAC seem to be exchangeable regimens in intermediate- and advanced-stage classical HL in pediatric patients.

Granulosa cell subtypes respond by autophagy or cell death to oxLDL-dependent activation of the oxidized lipoprotein receptor 1 and toll-like 4 receptor.

Autophagic cell death has been observed in granulosa cell cultures via the oxLDL-dependent activation of lectin-like oxidized low density lipoprotein receptor 1 (LOX-1). This activation might differ for cytokeratin-positive (CK(+)) and CK(-) granulosa cells. In particular, LOX-1 and toll-like receptor 4 (TLR4), one of the pattern recognition receptors of innate immunity, might be diversely regulated. Granulosa cell subtype cultures were established from the follicle harvests of patients undergoing in vitro fertilization (IVF) therapy. In response to oxLDL treatment, the fibroblast-like CK(-) cells upregulated LOX-1 and exhibited reparative autophagy, which could be blocked with anti-LOX-1 antibody. The epithelioid-like CK(+) cells did not regulate LOX-1 expression upon oxLDL application, but the expression of TLR4 and CD14 increased between 0 and 36 h of oxLDL/nDL treatment. This upregulation was associated with nonapoptotic cell death based on the absence of cleaved caspase-3. Reactive oxygen species (ROS) increased with 12 h oxLDL application and steroidogenic acute regulatory (StAR) protein expression was negligible. In CK(-) cells, the inhibition of TLR4 downregulated LOX-1 and induced apoptosis. We concluded that CK(-) granulosa cells are protected against oxLDL-dependent apoptosis by TLR4, whereas, in CK(+) cells, oxLDL-induced TLR4 activation triggers nonapoptotic cell death. The CK(+) cells might represent immune-like granulosa cells involved in ovarian remodeling processes.