Original articleComparing different physical factors on serum TNF-α levels, chondrocyte apoptosis, caspase-3 and caspase-8 expression in osteoarthritis of the knee in rabbits☆
Introduction
Osteoarthritis (OA) is the most common joint disease and is a leading cause of chronic disability [1]. This disease is compounded by age, genetic factors, and mechanical forces, and is characterised by distinct changes in both superficial and interior cells within the cartilage [2]. The pathogenesis of OA remains unclear, but recent studies have revealed that apoptosis is associated with the onset and development of OA [3]. Apoptosis, a form of programmed cell death, is critical not only during development and tissue homeostasis, but also in the pathogenesis of a variety of diseases [4]. Blanco et al. have found that the proportion of apoptotic cells in OA is greater when compared to that in normal or healthy cartilage [5]. The greater proportion of apoptotic cells in OA implies that apoptosis plays an important role in the development of OA. In molecular studies, the expression of several caspases, such as caspase-3 and caspase-8, is increased in human osteoarthritic cartilage and in animal models [6], [7]. Additionally, tumour necrosis factor-α (TNF-α) is a pleiotropic cytokine that plays a central role in inflammation and apoptosis [8].
Millimetre waves (MW), pulsed electromagnetic fields (PEMFs), ultrasounds (US), low level laser therapy (LLLT) and short wave diathermy (SWD) are non-invasive techniques that are considered safe and effective forms of physiotherapy for the management of OA [9], [10], [11], [12], [13], [14].
We hypothesised that an effective treatment can significantly improve the progression of OA and can be monitored through the analysis of several key disease indicators, such as histological evaluation of the articular cartilage, serum TNF-α levels, expression of caspase-3 and caspase-8 and apoptosis of chondrocytes. In this study, we quantitively evaluated the effects of MW for 20 min, PEMFs, MW for 40 min, US, LLLT and SWD therapies on serum TNF-α levels, chondrocyte apoptosis, and caspase-3 and caspase-8 expression in rabbits with osteoarthritis of the knee. Our results may shed light on the efficacy of various physical therapies available to patients in the management OA of the knee.
Section snippets
Animals
A total of 64 New Zealand White (NZW) rabbits, 32 male and 32 female, 3 months of age and weighing 2–2.5 kg, were used for this study.
All animals were given a standard laboratory diet with drinking water and housed in individual cages with a 12-hour light-dark cycle at 20–26 °C. The research complied with national legislation and with Ministry of Health of the People's Republic of China Guide for the Care and Use of Laboratory Animals, and had local ethical committee approval. All the rabbits
The appearance of cartilage sections by H&E staining
In Fig. S1 (see the supplementary material associated with this article online), we found that normal rabbit cartilage (Group G) appeared as a thick layer of cartilage neatly arranged in a grid-like pattern. In the model group (Group H), the cartilage layer was thinner and contained fewer cartilage cells; these cells appeared in a less ordered structure. After treatment, the number of cartilage cells increased and the cells re-established an ordered pattern. The modified Mankin scores of the MW
Discussion
In this study, we evaluated the effects of six intervention factors on OA in the knee by using four indices: histological evaluation of the articular cartilage by H&E staining, analysis of serum TNF-α levels by ELISA, assessment of caspase-3 and caspase-8 expression by immunohistochemistry and apoptosis of chondrocytes by TUNEL. According to the graded scores based on the four indices (shown in Table 6), PEMFs and US were confirmed as the two most optimal physical intervention factors, whereas
Disclosure
We declare that we have no conflict of interest statement.
Authors’ contributions
Hua Guo conceived the study, performed the statistical and data analysis and drafted the manuscript. Qinglu Luo, Jinglong Zhang and Haidan Lin participated in experimental design of the study and data acquisition. Chengqi He conceived the study and is the primary author of the manuscript. All authors read and approved the final manuscript.
Acknowledgments
We thank Yuqing Wang for the statistical and data analysis. We thank the National Natural Science Fund (No. 30672215) for the financial support.
References (38)
- et al.
Characterization of pro-apoptotic and matrix-degradative gene expression following induction of osteoarthritis in mature and aged rabbits
Osteoarthritis Cartilage
(2006) - et al.
Treatment of chronic pain with millimetre wave therapy (MWT) in patients with diffuse connective tissue diseases: a pilot case series study
Eur J Pain
(2003) - et al.
A review of the literature on shortwave diathermy as applied to osteoarthritis of the knee
Physiotherapy
(1999) - et al.
Cytokines, tumor necrosis factor-α and interleukin-1 beta, differentially regulate apoptosis in osteoarthritis cultured human chondrocytes
Osteoarthritis Cartil
(2006) - et al.
Characterization of pro-apoptotic and matrix-degradative gene expression following induction of osteoarthritis in mature and aged rabbits
Osteoarthritis Cartilage
(2006) - et al.
Ultrasound for osteoarthritis of the knee (a systematic review)
Physiotherapy
(2000) - et al.
Treatment of chronic pain with millimetre wave therapy (MWT) in patients with diffuse connective tissue diseases: a pilot case series study
Eur J Pain
(2003) - et al.
A review of the literature on shortwave Diathermy as applied to osteoarthritis of the knee
Physiotherapy
(1999) Angiogenesis in osteoarthritis and spondylosis: successful repair with undesirable outcomes
Curr Opin Rheumatol
(2004)- et al.
Osteoarthritis
J Cell Physiol
(2007)
Osteoarthritis chondrocytes die by apoptosis. A possible pathway for osteoarthritis pathology
Arthrifts Rheum
The molecular biology of apoptosis
Proc Natl Acad Sci USA
Apoptotic cell death is not a widespread phenomenon in normal aging and osteoarthritis human articular knee cartilage: a study of proliferation, programmed cell death (apoptosis), and viability of chondrocytes in normal and osteoarthritic human knee cartilage
Arthritis Rheum
Increased apoptosis in human osteoarthritic cartilage corresponds to reduced cell density and expression of caspse-3
Arthritis Rheum
Serum concentrations of TNF-α and its soluble receptors in patients with adrenal tumors treated by surgery
Int J Mol Sci
Some basic properties of biological tissues for potential biomedical applications of millimeter waves
J Microw Power
Nonpharmacologic management of osteoarthritis
Curr Opin Rheumatol
Short term efficacy of ibuprofen phonophoresis versus continuous ultrasound therapy in knee osteoarthritis
Swiss Med Wkly
Low power laser treatment in patients with knee osteoarthritis
Swiss Med Wkly
Cited by (50)
Effects of electromagnetic fields on osteoarthritis
2019, Biomedicine and PharmacotherapyCitation Excerpt :Ciombor et al. [28] have demonstrated that PEMF therapy favorably affects cartilage homeostasis through targeting TGFβ, which is believed to upregulate gene expression for aggrecan, downregulate matrix metalloprotease and IL-1 activity, and upregulate inhibitors of matrix metalloprotease. Another study using an anterior cruciate ligament transection (ACLT) rabbit model, confirmed the down-regulation of serum tumor necrosis factor-α (TNF-α) levels, preventing cartilage degeneration after 10-day PEMF therapy (PEMFs for 30 min: 8 mw/cm2, 75 Hz) [35]. PEMFs also increased the mRNA expression of inhibitor of apoptosis protein and decreased Bax mRNA expression in rats, inhibiting ovariectomy-induced (OVX) cartilage degeneration [36].
State of art and limitations in genetic engineering to induce stable chondrogenic phenotype
2018, Biotechnology AdvancesCitation Excerpt :To restrict transgene expression in inflammatory environment and of the inflammatory cells (reducing side effects), transgene expression under the control of IL-1 enhancer / IL-6 proximal promoter (Henningsson et al., 2012; Geurts et al., 2007) or cyclooxygenase (COX) 2 promoter (Rachakonda et al., 2008) and CXC motif chemokine 10 (CXCL-10) promoter (Broeren et al., 2016) have been used in animal models. The major limitation in successfully clinically translating gene-based therapies still remains the unsuitability of the in vivo models (e.g. AIA (Kim et al., 2002); SCW (Vermeij et al., 2015); CIA (Kim et al., 2003); adjuvant-induced arthritis (Sukedai et al., 2011); intra-articular injection of IL (Oligino et al., 1999; Gouze et al., 2003b) for RA, meniscectomy and ligament transection (Zhang et al., 2015; Wang et al., 2006; Fernandes et al., 1999; Guo et al., 2011; Nasi et al., 2017; Sun et al., 2016; Lee and Im, 2012); and chronic osteochondral models for OA (Frisbie et al., 2002)) to mimic the complexity of the human pathology (Miller et al., 2014; Kuyinu et al., 2016; Bevaart et al., 2010). Indeed, candidate genes that showed effective outcomes in animal models, did not show beneficial effects in human patients (e.g. TNF-α (Chevalier et al., 2015) and IL-1β (Nasi et al., 2017; Chevalier et al., 2009) inhibition in patients with OA).
Pulsed electromagnetic field ameliorates cartilage degeneration by inhibiting mitogen-activated protein kinases in a rat model of osteoarthritis
2017, Physical Therapy in SportCitation Excerpt :Although the results appeared to have deteriorated at 2 years, outcomes were still superior to pretreatment levels (A. Gobbi et al., 2014). In vivo studies have shown that pulsed electromagnetic field preserves the morphology of articular cartilage and slows the progression of osteoarthritis lesions in the knee of aged osteoarthritic guinea pigs (M. Fini et al., 2005), protects cartilage by inhibiting serum tumor necrosis factor-α(TNF-α) levels in anterior cruciate ligament transection (ACLT) rabbits (H. Guo et al., 2011), prevents ovariectomy-induced cartilage degeneration through up-regulation of X-linked inhibitor of apoptosis protein mRNA expression and down-regulation of Bax mRNA expression in rats (S. Li et al., 2011), and inhibit chondrocyte apoptosis and downregulate metalloproteinase-13 expression of knee joint cartilage in ovariectomized rats (Q. Luo et al., 2009). Our previous study also demonstrated the therapeutic effect of pulsed electromagnetic field on experimental osteoarthritis mediated via inhibition of apoptosis in chondrocytes (W. Xie, Zhou, Luo, Liu, & He, 2014).
- ☆
Chengqi He, the corresponding author certifies that all authors agree to the content, presentation, and decision to submit the manuscript.