Increased Oxidative Stress Response in Granulocytes from Older Patients with a Hip Fracture May Account for Slow Regeneration

Abstract

Proximal femur fracture, a typical fracture of the elderly, is often associated with morbidity, reduced quality of life, impaired physical function and increased mortality. There exists evidence that responses of the hematopoietic microenvironment to fractures change with age. Therefore, we investigated oxidative stress markers and oxidative stress-related MAPK activation in granulocytes from the young and the elderly with and without fractured long bones. Lipid peroxidation levels were increased in the elderly controls and patients. Aged granulocytes were more sensitive towards oxidative stress induced damage than young granulocytes. This might be due to the basally increased expression of SOD-1 in the elderly, which was not further induced by fractures, as observed in young patients. This might be caused by an altered MAPK activation. In aged granulocytes basal p38 and JNK activities were increased and basal ERK1/2 activity was decreased. Following fracture, JNK activity decreased, while ERK1/2 and p38 activities increased in both age groups. Control experiments with HL60 cells revealed that the observed p38 activation depends strongly on age. Summarizing, we observed age-dependent changes in the oxidative stress response system of granulocytes after fractures, for example, altered MAPK activation and SOD-1 expression. This makes aged granulocytes vulnerable to the stress stimuli of the fracture and following surgery.

Primary human osteoblasts with reduced alkaline phosphatase and matrix mineralization baseline capacity are responsive to extremely low frequency pulsed electromagnetic field exposure — Clinical implication possible

“…Chemiluminescent signals were detected with a CCD camera. Signal intensities were determined by densitometry using the ImageJ software (NIH, Bethesda, USA) and normalized to the corresponding GAPDH signals (Wang et al, 2014). …”

Protective effect of berberine against oxidative stress-induced apoptosis in rat bone marrow-derived mesenchymal stem cells

“…Previous studies have demonstrated that BMSCs injected into fracture sites are confronted with its apoptosis within a few days on account of harsh microenvironment conditions with oxidative stress, which is a state of imbalance between reactibe oxygen species (ROS) generation and intracellular antioxidants, resulting in cellular damage, and eventually leading to cell death (11)(12)(13). Therefore, strategies to protect the implantation of BMSCs from apoptosis and to improve their survivability in oxidative stress are therapeutically attractive in MSC-based therapy for delayed union, nonunion and persistent bone defects.…”

Redox Status in Patients with Femoral Neck Fractures

“…Although there has been an increase in TBARS values in patients with fractures, this increase was not statistically significant ( Figure 3). Wang and colleagues also showed an increase in this parameter in elderly patients with femoral neck fractures (2). In their study, they investigated the value of TBARS in younger patients with femur fractures and have obtained results that show a statistically significant increase unlike those observed in elderly patients.…”

“…It transfers the body weight from the pelvic bone to the shinbone (1). Femur fractures are a significant cause of morbidity and mortality among the locomotor apparatus injuries, especially in the elderly population (2). Although any part of this bone can break, the femoral neck or hip is the most common part to fracture (3).…”