Increasing studies have reported that intervertebral disc degeneration (IVDD) is the main contributor and independent risk factor for low back pain (LBP), it would be, therefore, enlightening that investigating the exact pathogenesis of IVDD and developing target-specific molecular drugs in the future. Ferroptosis is a new form of programmed cell death characterized by glutathione (GSH) depletion, and inactivation of the regulatory core of the antioxidant system (glutathione system) GPX4. The close relationship of oxidative stress and ferroptosis has been studied in various of diseases, but the crosstalk between of oxidative stress and ferroptosis has not been explored in IVDD. At the beginning of the current study, we proved that Sirt3 decreases and ferroptosis occurs after IVDD. Next, we found that knockout of Sirt3 (Sirt3-/-) promoted IVDD and poor pain-related behavioral scores via increasing oxidative stress-induced ferroptosis. The (immunoprecipitation coupled with mass spectrometry) IP/MS and co-IP demonstrated that USP11 was identified to stabilize Sirt3 via directly binding to Sirt3 and deubiquitinating Sirt3. Overexpression of USP11 significantly ameliorate oxidative stress-induced ferroptosis, thus relieving IVDD by increasing Sirt3. Moreover, knockout of USP11 in vivo (USP11-/-) resulted in exacerbated IVDD and poor pain-related behavioral scores, which could be reversed by overexpression of Sirt3 in intervertebral disc. In conclusion, the current study emphasized the importance of the interaction of USP11 and Sirt3 in the pathological process of IVDD via regulating oxidative stress-induced ferroptosis, and USP11-mediated oxidative stress-induced ferroptosis is identified as a promising target for treating IVDD.
The abnormal activation of the inflammatory microenvironment is frequently accompanied by metabolic changes that affect the development of various diseases. However, the relationship between metabolic reprogramming and intervertebral disc degeneration (IVDD) remains unclear. This study aims to reveal the metabolic changes in nucleus pulposus (NPCs) during IVDD and investigate the mechanism of glycolysis‐derived lactate on NPCs. Single‐cell RNA sequencing reveals that during IVDD, NPCs are characterized by excessively elevated glycolysis, and the resultant lactate causes the dysfunction of NPCs via ferroptosis activation. Mechanistically, lactate results in the transcription of Acyl‐CoA Synthetase Long Chain Family Member 4 (ACSL4) via promoting Histon H3K18 lactylation. Interestingly, lactate can also increase the lactylation of ACSL4 at K412 site. In addition, lactate‐induced decreased expression of Sirtuin‐3 (SIRT3), and further cause the elevation of ACSL4 lactylation. Finally, animal experiments demonstrate that inhibiting glycolysis through gene silencing with adenoviral‐associated viruses 9 (AAV9)‐si‐Ldha or chemical treatment using 2‐deoxy‐D‐glucose can suppress lactate production and lactylation, thereby ameliorating ferroptosis and NPC dysfunction. The findings of this study indicate that lactate plays a crucial role in IVDD by activating ferroptosis and that interventions aimed at lactate production can offer a potential therapeutical option for patients with IVDD.
Although anterior and posterior decompression surgery are both reported to treat patients with myelopathy caused by ossification of the posterior longitudinal ligament (OPLL). The surgical strategy of the disease is still controversial when the OPLL is multilevel and severe. This present study reports the preliminary clinical results of a novel technique named anterior controllable antidisplacement and fusion (ACAF) for the treatment of multilevel-severe OPLL with myelopathy.
1 January 2021 in Oxidative Medicine and Cellular Longevity
Chronic low back pain (CLBP) has been proved to be the dominating cause of disability in patients with lumbar degenerative diseases. Of the various etiological factors, intervertebral disc degeneration (IVDD) has been the dominating cause. In the past few decades, the role and changes of nerve systems, especially the peripheral sensory fibers and their neurotransmitters, in the induction and progression of IVDD have attracted growing concerns. The expression of many neuropeptides, such as SP, NPY, and CGRP, in the nociceptive pathways is increased during the progression of IVDD and responsible for the discogenic pain. Here, the role of CGRP in the progression of IVDD was firstly investigated both in vitro and in vivo. Firstly, we confirmed that human degenerated intervertebral disc tissue exhibited elevated expression of CGRP and its receptor. Secondly, in vitro experiments suggested that CGRP could inhibit the proliferation and induce apoptosis in human nucleus pulposus (NP) cells, as well as promote inflammation and degenerated phenotypes through activating NF‐κB and MAPK signaling pathways. Thirdly, CGRP receptor antagonist, Rimegepant, can ameliorate the adverse effects of CGRP imposed on NP cells, which were confirmed in vitro and in vivo. Our results will bring about a brand‐new insight into the roles of neuromodulation in IVDD and related therapeutic attempts.
Intervertebral disc degeneration (IVDD), a widely known contributor to low back pain (LBP), has been proved to be a global health challenging conundrum. Hesperidin (hesperetin-7-O-rutinoside, HRD) is a flavanone glycoside that belongs to the subgroup of citrus flavonoids with therapeutic effect on various diseases due to its anti-inflammatory, antioxidant properties. However, the effect of HRD on IVDD remains elusive. The human nucleus pulposus tissues were harvested for isolating human nucleus pulposus (HNP) cells to verify the expression of Nrf2. The biological effect of HRD on HNP cells were assessed in vitro, and the in vivo therapeutic effects of HRD were assessed in mice. Firstly, we found that the expression of Nrf2 was decreased with the progression of degeneration in degenerated human nucleus pulposus tissue. Subsequently, we confirmed that HRD could mitigate oxidative stress-induced ferroptosis in nucleus pulposus cells via enhancing the expression of Nrf2 axis and suppressing the NF-κB pathway to protect intervertebral disc from degeneration in vitro. Finally, the therapeutic effects of HRD were confirmed in vivo. The current study proved for the first time that HRD may protect HNP cells from degeneration by suppressing ferroptosis in an oxidative stress-dependent via enhancing the expression of Nrf2 and suppressing the NF-κB pathway. The evidence will provide a possible basis for future targeted treatment for IVDD