Dexamethasone Induced Osteocyte Apoptosis in Steroid-Induced Femoral Head Osteonecrosis through ROS-Mediated Oxidative Stress

© 2024 The Authors. Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd..

OBJECTIVE: Glucocorticoid (GC) overuse is strongly associated with steroid-induced osteonecrosis of the femoral head (SINFH). However, the underlying mechanism of SINFH remains unclear. This study aims to investigate the effect of dexamethasone (Dex)-induced oxidative stress on osteocyte apoptosis and the underlying mechanisms.

METHODS: Ten patients with SINFH and 10 patients with developmental dysplasia of the hips (DDH) were enrolled in our study. Sixty rats were randomly assigned to the Control, Dex, Dex + N-Acetyl-L-cysteine (NAC), Dex + Dibenziodolium chloride (DPI), NAC, and DPI groups. Magnetic resonance imaging (MRI) was used to examine edema in the femoral head of rats. Histopathological staining was performed to assess osteonecrosis. Immunofluorescence staining with TUNEL and 8-OHdG was conducted to evaluate osteocyte apoptosis and oxidative damage. Immunohistochemical staining was carried out to detect the expression of NOX1, NOX2, and NOX4. Viability and apoptosis of MLO-Y4 cells were measured using the CCK-8 assay and TUNEL staining. 8-OHdG staining was conducted to detect oxidative stress. 2',7'-Dichlorodihydrofluorescein diacetate (DCFH-DA) staining was performed to measure reactive oxygen species (ROS). The expression of NOX1, NOX2, and NOX4 in MLO-Y4 cells was analyzed by Western blotting. Multiple comparisons were performed using one-way analysis of variance (ANOVA).

RESULTS: In patients and the rat model, hematoxylin-eosin (HE) staining revealed a significantly higher rate of empty lacunae in the SINFH group than in the DDH group. Immunofluorescence staining indicated a significant increase in TUNEL-positive cells and 8-OHdG-positive cells in the SINFH group compared to the DDH group. Immunohistochemical staining demonstrated a significant increase in the expression of NOX1, NOX2, and NOX4 proteins in SINFH patients compared to DDH patients. Moreover, immunohistochemical staining showed a significant increase in the proportion of NOX2-positive cells compared to the Control group in the femoral head of rats. In vitro, Dex significantly inhibited the viability of osteocyte cells and induced apoptosis. After Dex treatment, the intracellular ROS level increased. However, Dex treatment did not alter the expression of NOX proteins in vitro. Additionally, NAC and DPI inhibited the generation of intracellular ROS and partially alleviated osteocyte apoptosis in vivo and in vitro.

CONCLUSION: This study demonstrates that GC promotes apoptosis of osteocyte cells through ROS-induced oxidative stress. Furthermore, we found that the increased expression of NOXs induced by GC serves as an important source of ROS generation.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:16

Enthalten in:

Orthopaedic surgery - 16(2024), 3 vom: 22. März, Seite 733-744

Sprache:

Englisch

Beteiligte Personen:

Zhang, Xinglong [VerfasserIn]
Yang, Zhenhuan [VerfasserIn]
Xu, Qian [VerfasserIn]
Xu, Chunlei [VerfasserIn]
Shi, Wei [VerfasserIn]
Pang, Ran [VerfasserIn]
Zhang, Kai [VerfasserIn]
Liang, Xinyu [VerfasserIn]
Li, Hui [VerfasserIn]
Li, Zhijun [VerfasserIn]
Zhang, Huafeng [VerfasserIn]

Links:

Volltext

Themen:

7S5I7G3JQL
Apoptosis
Dexamethasone
Glucocorticoids
Journal Article
Osteocyte
Oxidative stress
Reactive Oxygen Species
Reactive oxygen species
Steroid-induced femoral head osteonecrosis
Steroids

Anmerkungen:

Date Completed 12.03.2024

Date Revised 13.03.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1111/os.14010

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM368741826