Phospholipase A2 activity in herniated lumbar discs

Phospholipase A2 inhibitor-loaded micellar nanoparticles attenuate inflammation and mitigate osteoarthritis progression

Treating osteoarthritis (OA) remains a major clinical challenge. Despite recent advances in drug discovery and development, no disease-modifying drug for knee OA has emerged with any notable clinical success, in part, due to the lack of valid and responsive therapeutic targets and poor drug delivery within knee joints. In this work, we show that the amount of secretory phospholipase A₂ (sPLA₂) enzyme increases in the articular cartilage in human and mouse OA cartilage tissues. We hypothesize that the inhibition of sPLA₂ activity may be an effective treatment strategy for OA. To develop an sPLA₂-responsive and nanoparticle (NP)-based interventional platform for OA management, we incorporated an sPLA₂ inhibitor (sPLA₂i) into the phospholipid membrane of micelles. The engineered sPLA₂i-loaded micellar NPs (sPLA₂i-NPs) were able to penetrate deep into the cartilage matrix, prolong retention in the joint space, and mitigate OA progression. These findings suggest that sPLA₂i-NPs can be promising therapeutic agents for OA treatment.

The Immune Privilege of the Intervertebral Disc: Implications for Intervertebral Disc Degeneration Treatment

The intervertebral disc (IVD) is the largest avascular organ of the body. It is composed of three parts: the nucleus pulposus (NP), the annulus fibrosus (AF) and the cartilaginous endplate (CEP). The central NP is surrounded by the AF and sandwiched by the two CEPs ever since its formation. This unique structure isolates the NP from the immune system of the host. Additionally, molecular factors expressed in IVD have been shown inhibitive effect on immune cells and cytokines infiltration. Therefore, the IVD has been identified as an immune privilege organ. The steady state of immune privilege is fundamental to the homeostasis of the IVD. The AF and the CEP, along with the immunosuppressive molecular factors are defined as the blood-NP barrier (BNB), which establishes a strong barrier to isolate the NP from the host immune system. When the BNB is damaged, the auto-immune response of the NP occurs with various downstream cascade reactions. This effect plays an important role in the whole process of IVD degeneration and related complications, such as herniation, sciatica and spontaneous herniated NP regression. Taken together, an enhanced understanding of the immune privilege of the IVD could provide new targets for the treatment of symptomatic IVD disease. However, the underlying mechanism above is still not fully clarified. Accordingly, the current study will extensively review and discuss studies regarding the immune privilege of the IVD.

Effect of percutaneous nucleoplasty with coblation on phospholipase A2 activity in the intervertebral disks of an animal model of intervertebral disk degeneration: a randomized controlled trial

BACKGROUND

This randomized controlled trial was carried out to (1) evaluate the effect of nucleoplasty with coblation on the PLA2 activity in the degenerative intervertebral disks of an animal model and (2) explore the possible therapeutic mechanism of coblation in addition to the current theory, which focuses on decreasing the intradiskal pressure in the treatment of intervertebral disk degeneration.

METHODS

Thirty-six animal models of intervertebral disk degeneration were successfully established and then randomly divided into two groups: the coblation group (n = 18) and coblation control group (n = 18). Nucleoplasty using coblation was performed in the coblation group. L4-5 and L5-6 intervertebral disk samples were harvested and analyzed for PLA2 activity in different groups at different time points.

RESULTS

The PLA2 activity in the coblation control group was significantly higher than that in the control group (194.86 ± 11.80 and 80.68 ± 5.56, respectively; P < 0.01). There was a significant decrease in the PLA2 activity 1 week after coblation than at the real time after coblation (154.39 ± 7.99 and 184.98 ± 9.43, respectively; P < 0.001). The PLA2 activity at 1 month after coblation remained at a lower level than those at 1 week and at the real time after coblation (142.63 ± 10.72, 154.39 ± 7.99, and 184.98 ± 9.43, respectively), but there was no significant decrease in the PLA2 activity between 1 week and 1 month after coblation.

CONCLUSIONS

Coblation appeared to effectively degrade the PLA2 activity in the degenerative intervertebral disks of this animal model. This represents a potential mechanism for the clinical use of coblation in the treatment of low back pain.

Effectiveness and cost-effectiveness analysis of neuroreflexotherapy for subacute and chronic low back pain in routine general practice: a cluster randomized, controlled trial

STUDY DESIGN

A cluster randomized, controlled trial was performed.

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of adding patients' referral to neuroreflexotherapy intervention to the usual management of subacute and chronic low back pain in routine general practice.

SUMMARY OF BACKGROUND DATA

Neuroreflexotherapy consists of the temporary implantation of epidermal devices in trigger points in the back and referred tender points in the ear. The efficacy of this procedure for treating subacute and chronic low back pain has been demonstrated in previous randomized, double-blind, controlled clinical trials.

METHODS

Twenty-one primary care physicians working in seven primary care centers of the Spanish National Health Service in Palma de Mallorca, Spain, were randomly assigned to the intervention group (n = 11) or the control group (n = 10). The physicians recruited patients who had low back pain that had lasted for 14 or more days despite drug treatment and who did not meet criteria for surgery. The 45 patients recruited by physicians from the control group were treated according to the standard protocol, whereas the 59 patients recruited by physicians from the intervention group were, in addition, referred to neuroreflexotherapy intervention. The analysis of variables was performed taking into account that physicians, not patients, were randomly assigned.

RESULTS

Patients underwent clinical evaluations at baseline and 15, 60, and 365 days later. At baseline, median intensity of pain was higher in patients undergoing neuroreflexotherapy than in control patients (visual analogue scale, 6.07; range, 4.67-8.80 vs. 5.15, range 4.11-8.00) and median duration of pain was also higher (48.1, range 28.4-211.1 vs. 17.5, range 15.0-91.5 days). At the last follow-up visit, patients treated with neuroreflexotherapy showed greater improvement than did control patients in low back pain (visual analogue scale, 5.5; range, 3.7-8.8 vs. 1.9; range, -1.2-3.0; P < 0.001); referred pain (visual analogue scale, 3.6; range, 2.7-7.3 vs. 0.6; range, -1.5-2.0; P = 0.001); and disability (Roland-Morris scale, 8.7; range, 2.0-13.3 vs. 2.0; range, -1.5-6.7; P = 0.007). Moreover, neuroreflexotherapy intervention was associated with a significantly (P < 0.035) lower number of consultations to private or public specialists, fewer indications of radiographs by primary care physicians, lower cost of drug treatment, and less duration of sick leave throughout the follow-up period. There were also differences in favor of neuroreflexotherapy intervention in the cost-effectiveness ratio for pain, disability, and quality of life that persisted in the most optimistic, the most conservative, and the average (break-even case) assumptions.

CONCLUSIONS

Referral to neuroreflexotherapy intervention improves the effectiveness and cost-effectiveness of the management of nonspecific low back pain.