Ozone therapy (O2-O3) alleviates the progression of early intervertebral disc degeneration via the inhibition of oxidative stress and the interception of the PI3K/Akt/NF-κB signaling pathway.

Intervertebral disc degeneration (IDD) stands for the most frequent cause of low back pain. Finding a cure for this disease is an important challenge as current conservative treatments and surgical interventions fail to bring a solution to this disease. Ozone therapy (O2-O3) has yielded outstanding outcomes in intervertebral disc pathology. The ozone's efficacy in the treatment of IDD remains unconfirmed. This study aimed to assess the effectiveness of intradiscal ozone injection on IDD induced in a rat. Effects of ozone therapy on the viability of nucleus pulposus cells were evaluated by CCK-8 assays. Macrophage immunoreactivity was detected by immunohistochemical, the expression of collagen type II was evaluated by western blot, and measurement of oxidative stress parameters was realized. Molecular docking studies were carried out in order to predict the interaction formed between O3 and the target enzymes, on the one hand, O3 with PI3K and, on the other hand, O3 with COX-2. IRM, X-ray, hematoxylin-eosin, and bleu alcian staining were realized to assess the therapeutic impacts of ozone in the puncture-induced rat model of IDD. In vivo, O3 ameliorated the IDD in the early stage of this disease. It was also displayed in molecular docking that O3 might bind to PI3K to suppress the PI3K/Akt/NF-κB signaling pathway. This study's results show that the O3 should be administered at the low grade of IDD and at an early stage because it cannot restore the advanced inflammatory alteration of the IVD. Our results corroborated also that O3 inhibits the progression of IDD via the PI3K/Akt/NF-κB signaling pathway, which supports O3 as an effective therapeutic option for treating IDD.

Original animal model of lumbar disc degeneration.

PURPOSE: Disc degeneration (DD) is a common cause of low back pain, which represents one of the most widespread public health problems in the world. Therefore, the establishment of a reproducible animal model is indispensable to understand the pathogenic mechanisms of DD and to test new therapeutic strategies. From this perspective, the fundamental objective of this study was to elucidate the effect of ovariectomy in establishing a new animal model of DD in rats. METHODS: 36 female Sprague-Dawley rats were divided into four groups of 9 rats: Group 1: Negative control (Sham): Only an abdominal skin incision and sutures were performed. Group 2: Ovariectomy (OVX): Removal of two ovaries through a transverse incision in the middle of the abdomen. Group 3: Puncture (Punct): Puncture of lumbar intervertebral discs (L3/4, L4/5, and L5/6) by a 21 G needle. Group 4: Puncture+ovariectomy (Punct+OVX): Removal of two ovaries and puncture of L3/4, L4/5, and L5/6 discs. The rats were euthanized 1, 3, and 6 weeks post-surgery, and the discs were harvested. Validity was assessed by radiography, histology, and biochemistry (water content). RESULTS: Disc height, water content, and histologic score decreased significantly in the last 3 groups and at all three-time points (P < 0.05). DD progressed over time in the Punct and Punct+OVX groups (P < 0.05). The changes were more severe in the Punct+OVX group compared to the Punct group and the OVX group. CONCLUSION: The combination of puncture and ovariectomy induced rapid and progressive DD in the lumbar discs of rats without spontaneous recovery.

Establishment of an Animal Model of Disk Degeneration by Intradiskal Injection of Monosodium Iodoacetate.

BACKGROUND: Disk degeneration (DD) stands for the most common cause of low back pain. The establishment of an animal model plays an intrinsic role in the clarification of the physiopathology of DD. The purpose of this study is to select an optimal dose of monosodium iodoacetate (MIA) that may generate a reliable model of DD. METHODS: Thirty-four rats were used in this study. The disks (Co7/8, Co8/9, and Co 9/10) received 1 shot of intradiskal injection of 0.02 mg, 0.1 mg, and 0.5 mg of MIA solution, respectively. Half of the rats were euthanized 3 weeks after MIA injection, and the other half 6 weeks after injection. RESULTS: Magnetic resonance imaging evaluation showed that the mean T2-weighted signal intensity at 6 weeks decreased significantly in the 0.1 and 0.5 mg groups. The disk height of the control group was significantly higher than those of the 0.1 mg and 0.5 mg groups. Histologic and macroscopic results revealed time-and-dose-depending degeneration in the disks that received MIA. Additionally, MIA produced cell death in the nucleus pulposus cells with an elevated percentage. The injected disk with 0.1 mg MIA demonstrated a progressive degeneration, the disk injected with 0.5 mg MIA induced DD acutely 3 weeks post MIA injection, while the dose of 0.02 mg of MIA did not show much degeneration. CONCLUSIONS: We concluded that 0.1 mg MIA is the most suitable dose to establish a model of DD, which enabled us to replicate the onset, progression, and outcome of diverse histopathologies of DD in the clinic.

Impact of Needle Size on the Onset and the Progression of Disc Degeneration in Rats.

BACKGROUND: Numerous animal models of intervertebral disc (IVD) degeneration have been proposed in the literature. The rat caudal disc has been used in disc degeneration studies because of its low cost and simplicity. However, no consensus on the size of the needle to be used during this process has been reached, yet. OBJECTIVES: This study aims to select an optimal needle size to establish a reproducible IVD degeneration model. STUDY DESIGN: This is a randomized, experimental trial. SETTING: Cell therapy and experimental surgery of musculoskeletal system LR18SP1 Lab, The Faculty of Medicine of Sfax, Tunisia. METHODS: The validity was verified by magnetic resonance imaging (MRI), histological, and immunohistochemical examinations. RESULTS: The MRI, histological, and immunohistochemical examinations showed that a disc that is perforated with a 21G needle degenerated acutely one week after the surgery, while a 29G needle puncture failed to develop disc degeneration. A 25G needle induced progressive degeneration in the IVD. LIMITATIONS: This study was not very long (6 weeks). CONCLUSIONS: We conclude that the size of the needle affects the onset and the progression of disc degeneration; a larger needle size leads to a more extended histological and radiographic degeneration within the IVD and in a relatively short time. Therefore, a 21G needle is an optimal choice to induce rapid degeneration in rats' caudal discs. However, the use of a 29G needle failed to establish a degenerative IVD model, which makes it ideal for IVD injection of drugs, plasmids, and growth factors. A 25G needle may be used to induce gradual degeneration.