Autogenic mesenchymal stem cells for intervertebral disc regeneration

SR9009 attenuates inflammation-related NPMSC pyroptosis and IVDD through NR1D1/NLRP3/IL-1β pathway

Intervertebral disc is a highly rhythmical tissue. As a key factor linking biorhythm and inflammatory response, the shielding effect of NR1D1 in the process of intervertebral disc degeneration remains unclear. Here, we first confirmed that NR1D1 in the nucleus pulposus tissue presents periodic rhythmic changes and decreases in expression with intervertebral disc degeneration. Second, when NR1D1 was activated by SR9009 in vitro, NLRP3 inflammasome assembly and IL-1β production were inhibited, while ECM synthesis was increased. Finally, the vivo experiments further confirmed that the activation of NR1D1 can delay the process of disc degeneration to a certain extent. Mechanistically, we demonstrate that NR1D1 can bind to IL-1β and NLRP3 promoters, and that the NR1D1/NLRP3/IL-1β pathway is involved in this process. Our results demonstrate that the activation of NR1D1 can effectively reduce IL-1β secretion, alleviate LPS-induced NPMSC pyroptosis, and protect ECM degeneration.

Manipulation of osteogenic and adipogenic differentiation of human degenerative disc and ligamentum flavum derived progenitor cells using IL-1β, IL-19, and IL-20

PURPOSE

To elucidate whether pro-inflammatory cytokines might influence the commitment of intervertebral disc (IVD)- and ligamentum flavum (LF)-derived progenitor cells toward either osteogenesis or adipogenesis, specifically Interleukin-1β (IL-1β), IL-19, and IL-20.

METHODS

Sixty patients with degenerative spondylolisthesis and lumbar or lumbosacral spinal stenosis were included in the study. Injuries to the spine, infections, and benign or malignant tumors were excluded. From nine patient samples, IVD- and LF-derived cells were isolated after primary culture, and two clinical samples were excluded due to mycoplasma infection. The effects of IL-1β, IL-19, as well as IL-20 in regulating osteogenic and adipogenic differentiation in vitro were investigated.

RESULTS

Primary IVD- and LF-derived cells were found to have a similar cell morphology and profile of surface markers (CD44, CD90, and CD105) as placenta-derived mesenchymal stem cells (MSCs). Primary IVD/LF cells have a high capacity to differentiate into osteocytes and adipocytes. IL-19 had a tendency to promote adipogenesis. IL-20 inhibited osteogenesis and promoted adipogenesis; IL-1β promoted osteogenesis but inhibited adipogenesis.

CONCLUSION

IL-1β, IL-19, and IL-20 impact the adipogenic and osteogenic differentiation of IVD-derived and LF-derived cells. Modulating the expression of IL-1β, IL-19, and IL-20 provides a potential avenue for controlling cell differentiation of IVD- and LF-derived cells, which might have beneficial effect for degenerative spondylolisthesis and spinal stenosis.

Between guidelines and clinical trials: evidence-based advice on the pharmacological management of non-specific chronic low back pain

The pharmacological management of nonspecific chronic low back pain (NCLBP) aims to restore patients' daily activities and improve their quality of life. The management of NCLBP is not well codified and extremely heterogeneous, and residual symptoms are common. Pharmacological management should be considered as co-adjuvant to non-pharmacological therapy, and should be guided by the symptoms reported by the patients. Depending on the individual severity of NCLPB, pharmacological management may range from nonopioid to opioid analgesics. It is important to identify patients with generalized sensory hypersensitivity, who may benefit from dedicated therapy. This article provides an evidence-based overview of the principles of pharmacological management of NCLPB.

Fixation of the Membrane during Matrix-Induced Autologous Chondrocyte Implantation in the Knee: A Systematic Review

Introduction: It is unclear whether the type of membrane used for matrix-assisted autologous chondrocyte implantation (mACI) influences results. A systematic review was conducted to investigate the midterm results of the three most common types of membrane fixation for mACI. Methods: This systematic review was conducted according to the 2020 PRISMA checklist. PubMed, Google Scholar, Embase, and Scopus online databases were accessed in August 2022. All the prospective clinical trials reporting outcomes of mACI in the knee were considered. Studies that describe the modality of membrane fixation (glued, glued, and sutured, no fixation) used for mACI were eligible. Studies that conducted a minimum of 12 months of follow-up were considered. The outcomes of interest were the Tegner Activity Scale and International Knee Documentation Committee (IKDC) score. The rate of failure and revisions were also collected. Results: Data from 26 studies (1539 procedures; 554 of 1539 (36%) were women) were retrieved. The mean follow-up was 42.6 (12 to 84) months. No difference between the groups was found in terms of mean duration of symptoms, age, BMI, gender, and defect size (P > 0.1). No difference was found in terms of the Tegner score (P = 0.3). When no fixation was used, a statistically significant higher IKDC compared to the other groups (P = 0.02) was evidenced. No difference was found in the rate of failure (P = 0.1). The no-fixation group evidenced a statistically significant lower rate of revisions (P = 0.02). Conclusions: No membrane fixation for mACI in the knee scored better than the fastening techniques at the midterm follow-up.

Importance of Matrix Cues on Intervertebral Disc Development, Degeneration, and Regeneration

Back pain is one of the leading causes of disability worldwide and is frequently caused by degeneration of the intervertebral discs. The discs’ development, homeostasis, and degeneration are driven by a complex series of biochemical and physical extracellular matrix cues produced by and transmitted to native cells. Thus, understanding the roles of different cues is essential for designing effective cellular and regenerative therapies. Omics technologies have helped identify many new matrix cues; however, comparatively few matrix molecules have thus far been incorporated into tissue engineered models. These include collagen type I and type II, laminins, glycosaminoglycans, and their biomimetic analogues. Modern biofabrication techniques, such as 3D bioprinting, are also enabling the spatial patterning of matrix molecules and growth factors to direct regional effects. These techniques should now be applied to biochemically, physically, and structurally relevant disc models incorporating disc and stem cells to investigate the drivers of healthy cell phenotype and differentiation. Such research will inform the development of efficacious regenerative therapies and improved clinical outcomes.

Mesenchymal stromal/stem cells and their exosomes application in the treatment of intervertebral disc disease: A promising frontier

Today, the application of mesenchymal stromal/stem cells (MSCs) and their exosomes to treat degenerative diseases has received attention. Due to the characteristics of these cells, such as self-renewability, differentiative and immunomodulatory effects, their use in laboratory and clinical studies shows promising results. However, the allogeneic transplantation problems of MSCs limit the use of these cells in the clinic. Scientists propose the application of exosomes to use from the therapeutic effect of MSCs and overcome their defects. These vesicles change the target cell behaviour and transcription profile by transferring various cargo such as proteins, mi-RNAs, and lipids. One of the degenerative tissue diseases in which MSCs and their exosomes are used in their treatment is intervertebral disc disease (IDD). Different factors such as genetics, nutrition, ageing, and environmental factors play a significant role in the onset and progression of this disease. These factors affect the cellular and molecular properties of the disc, leading to tissue destruction. Nucleus pulposus cells (NPCs) are among the most important cells involved in the pathogenesis of disc degeneration. MSCs exert their therapeutic effects by differentiating, reducing apoptosis, increasing proliferation, and decreasing senescence in NPCs. In addition, the use of MSCs and their exosomes also affects the annulus fibrosus and cartilaginous endplate cells in disc tissue and prevents disc degeneration progression.

Intradiscal injection for the management of low back pain

Low back pain (LBP) is a common clinical problem and a major cause of physical disability, imposing a prominent socioeconomic burden. Intervertebral disc degeneration (IDD) has been considered the main cause of LBP. The current treatments have limited efficacy because they cannot address the underlying degeneration. With an increased understanding of the complex pathological mechanism of IDD, various medications and biological reagents have been used for intradiscal injection for the treatment of LBP. There is increasing clinical evidence showing the benefits of these therapies on symptomatic relief and their potential for disc repair and regeneration by targeting the disrupted pathways underlying the cause of the disease. A brief overview of the potential and limitations for these therapies are provided in this review, based on the recent and available data from clinical trials and systematic reviews. Finally, future perspectives are discussed.

Small extracellular vesicles from hypoxic mesenchymal stem cells alleviate intervertebral disc degeneration by delivering miR-17-5p

Minimally invasive repair strategies are a very promising approach for the treatment of intervertebral disc degeneration (IDD). In recent years, small extracellular vesicles (sEVs) secreted from mesenchymal stem cells (MSCs) have been shown great potential in alleviating IDD. However, in vitro experiments, MSCs are usually exposed to a normoxic micro-environment, which differs greatly from the hypoxic micro-environment in vivo. The primary purpose of our research was to determine whether sEVs isolated from MSCs under hypoxic status (H-sEVs) exhibit a more beneficial effect on protecting IDD compared with sEVs derived from MSCs under normoxic status (N-sEVs). A tail IDD rat model and a series of experiments in vitro were conducted to compare the beneficial effects of PBS, N-sEVs, and H-sEVs treatment. Then, to validate the role of sEVs miRNAs in IDD, a miRNA microarray sequencing analysis and a series of rescue experiments were conducted. Luciferase activity, RNA-ChIP and western blot were performed to explore the potential mechanisms. The results indicate that sEVs alleviate IDD by ameliorating the homeostatic imbalance between anabolism and catabolism in vivo and in vitro. Microarray sequencing result shows that miR-17-5p is maximally enriched in H-sEVs. Toll-like receptor 4 (TLR4) was determined to be a target downstream gene of miR-17-5p. Finally, it was found that H-sEVs miR-17-5p may modulate proliferation and synthesis of human nucleus pulposus cells (HNPCs) matrix via TLR4 pathway. In conclusion, H-sEVs miR-17-5p alleviate IDD via promoting HNPCs matrix proliferation and synthesis, providing new therapeutic targets for IDD. STATEMENT OF SIGNIFICANCE: Intervertebral disc degeneration (IDD) is the primary cause of low back pain (LBP), which is a huge burden to society. Our research demonstrates for the first time that hypoxic pretreatment of small extracellular vesicles (H-sEVs) effectively alleviated the progress of IDD. In short, in the present research, we found that H-sEVs miR-17-5p could modulate proliferation and synthesis of nucleus pulposus cells (NPCs) matrix via TLR4/PI3K/AKT pathway. Therefore, hypoxic pre-treatment is a prospective and efficient method to optimize the therapeutic effect of MSCs-derived sEVs. miRNA and MSCs-derived sEVs combination may be a promising therapeutic approach for IDD.

New hope for intervertebral disc degeneration: bone marrow mesenchymal stem cells and exosomes derived from bone marrow mesenchymal stem cell transplantation

Bone marrow mesenchymal stem cells (BMSCs), multidirectional cells with self-renewal capacity, can differentiate into many cell types and play essential roles in tissue healing and regenerative medicine. Cell experiments and in vivo research in animal models have shown that BMSCs can repair degenerative discs by promoting cell proliferation and expressing extracellular matrix (ECM) components, such as type II collagen and protein-polysaccharides. Delaying or reversing the intervertebral disc (IVD) degeneration (IDD) process at an etiological level may be an effective strategy. However, despite increasingly in-depth research, some deficiencies in cell transplantation timing and strategy remain, preventing the clinical application of cell transplantation. Exosomes exhibit the characteristics of the mother cells from which they were secreted and can inhibit nucleus pulposus (NP) cell (NPC) apoptosis and delay IDD through intercellular communication. Furthermore, the use of exosomes effectively avoids problems associated with cell transplantation, such as immune rejection. This manuscript introduces almost all of the BMSCs and exosomes derived from BMSCs (BMSCs-Exos) described in the IDD literature. Many challenges regarding the use of cell transplantation and therapeutic exosome intervention for IDD remain to be overcome.

Surgical management of focal chondral defects of the knee: a Bayesian network meta-analysis

Background

Focal chondral defects of the knee are common. Several surgical techniques have been proposed for the management of chondral defects: microfractures (MFX), osteochondral autograft transplantation (OAT), autologous matrix-induced chondrogenesis (AMIC) and autologous chondrocyte implantation (ACI)—first generation (pACI), second generation (cACI) and third generation (mACI). A Bayesian network meta-analysis was conducted to compare these surgical strategies for chondral defects in knee at midterm follow-up.

Methods

This Bayesian network meta-analysis was conducted according to the PRISMA extension statement for reporting of systematic reviews incorporating network meta-analyses of health care interventions. PubMed, Google Scholar, Embase and Scopus databases were accessed in July 2021. All the prospective comparative clinical trials investigating two or more surgical interventions for chondral defects of the knee were accessed. The network meta-analyses were performed through a Bayesian hierarchical random-effects model analysis. The log odds ratio (LOR) effect measures were used for dichotomic variables, while the standardized mean difference (SMD) for the continuous variables.

Results

Data from 2220 procedures (36 articles) were retrieved. The median follow-up was 36 (24 to 60) months. The ANOVA test found good baseline comparability between symptoms duration, age, sex and body mass index. AMIC resulted in higher Lysholm score (SMD 3.97) and Tegner score (SMD 2.10). AMIC demonstrated the lowest rate of failures (LOR −0.22) and the lowest rate of revisions (LOR 0.89). As expected, MFX reported the lower rate of hypertrophy (LOR −0.17) followed by AMIC (LOR 0.21). No statistically significant inconsistency was found in the comparisons.

Conclusion

AMIC procedure for focal chondral defects of the knee performed better overall at approximately 3 years’ follow-up.

Tissue-Engineering of Human Intervertebral Disc: A Concise Review

Intervertebral disc (IVD) represents a structure of crucial structural and functional importance for human spine. Pathology of IVD institutes a frequently encountered condition in current clinical practice. Degenerative Disc Disease (DDD), the principal clinical representative of IVD pathology, constitutes an increasingly diagnosed spinal disorder associated with substantial morbidity and mortality in recent years. Despite the considerable incidence and socioeconomic burden of DDD, existing treatment modalities including conservative and surgical methods have been demonstrated to provide a limited therapeutic effect, being not capable of interrupting or reversing natural progress of underlying disease. These limitations underline the requirement for development of novel, innovative and more effective therapeutic strategies for DDD management. Within this literature framework, compromised IVD replacement with a viable IVD construct manufactured with Tissue-Engineering (TE) methods has been recommended as a promising therapeutic strategy for DDD. Existing preliminary preclinical data demonstrate that proper combination of cells from various sources, different scaffold materials and appropriate signaling molecules renders manufacturing of whole-IVD tissue-engineered constructs a technically feasible process. Aim of this narrative review is to critically summarize current published evidence regarding particular aspects of IVD-TE, primarily emphasizing in providing researchers in this field with practicable knowledge in order to enhance clinical translatability of their research and informing clinical practitioners about the features and capabilities of innovative TE science in the field of IVD-TE.

Basic Research on Tendon Repair: Strategies, Evaluation, and Development

Tendon is a fibro-elastic structure that links muscle and bone. Tendon injury can be divided into two types, chronic and acute. Each type of injury or degeneration can cause substantial pain and the loss of tendon function. The natural healing process of tendon injury is complex. According to the anatomical position of tendon tissue, the clinical results are different. The wound healing process includes three overlapping stages: wound healing, proliferation and tissue remodeling. Besides, the healing tendon also faces a high re-tear rate. Faced with the above difficulties, management of tendon injuries remains a clinical problem and needs to be solved urgently. In recent years, there are many new directions and advances in tendon healing. This review introduces tendon injury and sums up the development of tendon healing in recent years, including gene therapy, stem cell therapy, Platelet-rich plasma (PRP) therapy, growth factor and drug therapy and tissue engineering. Although most of these therapies have not yet developed to mature clinical application stage, with the repeated verification by researchers and continuous optimization of curative effect, that day will not be too far away.

Non-steroidal anti-inflammatory drugs and gabapentinoids for chronic lumbar pain: a Bayesian network meta-analysis of randomized controlled trials

INTRODUCTION

Several pharmacological therapies have been proposed for the management of chronic low back pain (LBP), but no consensus has been reached yet.

SOURCE OF DATA

Recent published literatures identified accessing PubMed, Google scholar, Embase and Scopus.

AREAS OF AGREEMENT

Exploring effective conservative alternatives to the surgical intervention is of especial interest.

AREAS OF CONTROVERSY

The efficacy and safety of non-steroidal anti-inflammatory drugs and gabapentinoids for chronic LBP are debated. Several clinical studies showed controversial results, and the most effective and safe class of drugs has not yet been clarified.

GROWING POINTS

The effects of selective and non-selective NSAIDs and gabapentinoids in chronic LBP are probably over-estimated.

AREAS TIMELY FOR DEVELOPING RESEARCH

The effect of behavioural changes, including exercise, should be explored, alone or in combination with drugs.

Risks of Intradiscal Orthobiologic Injections: A Review of the Literature and Case Series Presentation

BACKGROUND

Intervertebral disc disease (IDD) is responsible for a large portion of back pain with historically suboptimal treatments for long-term improvement. IDD pathogenesis is thought to arise at a cellular and biochemical level, making biologically based injections an area of clinical interest. Although human studies have shown promise, emerging data suggest there may be risks inherent to such injections that were previously unrecognized. The aim of this review is to summarize the known risks to date and provide mitigation steps to reduce potential complications in the future. In addition, we present a small case series of serious adverse events (SAEs) from our clinical practice.

METHODS

A literature review was performed to identify human intradiscal autologous biologic injection studies to date, including mesenchymal signaling cells (MSCs) and platelet-rich plasma (PRP) preparations, which were reviewed for complications. Cases of complication following intradiscal orthobiologic injection were identified from a single outpatient center and reviewed.

RESULTS

Publications of MSC-based intradiscal injection documented 136 total patients treated with two SAEs reported, one infection and one progressive disc herniation. Publications of PRP intradiscal injection included 194 patients with one SAE reported. We also review three cases of previously unpublished SAEs, including one case of confirmed infection with Cutibacterium acnes (C acnes) and two presumed cases of discitis without pathogen confirmation. Bone marrow concentrate was the injectate in all three cases.

CONCLUSIONS

Although biologic intradiscal injection shows promise for the treatment of discogenic back pain, there are inherent risks to be considered and mitigated. We currently recommend a leukocyte-rich PRP and a two-needle delivery technique coupled with intradiscal gentamicin to mitigate the risk of postinjection spondylodiscitis. Further research is needed using large registries to not only track clinical outcomes but also complication rates.

The Application of Mesenchymal Stromal Cells and Their Homing Capabilities to Regenerate the Intervertebral Disc

Chronic low back pain (LBP) remains a challenging condition to treat, and especially to cure. If conservative treatment approaches fail, the current “gold standard” for intervertebral disc degeneration (IDD)-provoked back pain is spinal fusion. However, due to its invasive and destructive nature, the focus of orthopedic research related to the intervertebral disc (IVD) has shifted more towards cell-based therapeutic approaches. They aim to reduce or even reverse the degenerative cascade by mimicking the human body’s physiological healing system. The implementation of progenitor and/or stem cells and, in particular, the delivery of mesenchymal stromal cells (MSCs) has revealed significant potential to cure the degenerated/injured IVD. Over the past decade, many research groups have invested efforts to find ways to utilize these cells as efficiently and sustainably as possible. This narrative literature review presents a summary of achievements made with the application of MSCs for the regeneration of the IVD in recent years, including their preclinical and clinical applications. Moreover, this review presents state-of-the-art strategies on how the homing capabilities of MSCs can be utilized to repair damaged or degenerated IVDs, as well as their current limitations and future perspectives.

Opioids for chronic low back pain management: a Bayesian network meta-analysis

Introduction: Chronic low back pain (LBP) is common, and some patients require opiates therapy. This Bayesian network meta-analysis (NMA) analyzed available randomized clinical trials (RCTs) on the use of opioids for LBP.Methods: All RCTs comparing two or more opioids for chronic LBP and reporting results under the Numeric Rating Scale were included. The following drugs were analyzed: fentanyl, morphine, tapentadol, oxycodone, buprenorphine, oxymorphone, tramadol. The NMA was performed through the STATA routine for Bayesian hierarchical random-effects model analysis, with standardized mean difference (SMD) effect measure. Data regarding the rate of adverse events and different drug formulations were also reported.Results: Data from 2933 patients were obtained, with a mean age of 53.30 ± 6.95 years. The mean duration of symptoms prior to beginning the trial was 95.16 ± 47.29 months. The mean follow-up was 3.29 ± 1.72 months. Among the analyzed compounds, oxymorphone, tapentadol and fentanyl showed the highest efficacy in terms of pain reduction.Conclusion: According to published level I evidence, oxymorphone, tapentadol and fentanyl were the most effective drugs in the treatment of chronic LBP. However, different formulation and pharmacokinetic characteristics need to be taken into consideration when choosing the ideal compound for a given patient.

Management of facet joints osteoarthritis associated with chronic low back pain: A systematic review

INTRODUCTION

Facet joint injections (FJI) and medial branch blocks (MBB) can be employed for chronic low back pain (LBP) using different drugs such as corticosteroids, hyaluronic acid, sarapin and local anaesthetics. This systematic review compares the results of injections obtained with different compounds in the management LBP originating from facet joints.

METHODS

The present systematic review was conducted according to the PRISMA statement. The literature search was performed in October 2020. All the randomized clinical trials concerning injection treatments for chronic LBP. Drugs rather than steroids, hyaluronic acid, anaesthetics and sarapin were not considered, as well as those reporting outcomes from combined treatments. The Oswestry Disability Index (ODI) and the numeric rating scale (NRS) were retrieved.

RESULTS

Data from 587 patients were retrieved. The mean follow-up was 12.4 ± 10.5 months. The mean age was 51.3 ± 9.6 years old. 57% (335/587) of patients were women. Steroids promoted a reduction of NRS by 28% (P < 0.0001) and an improvement of the ODI by 13.2% (P = 0.005), and local anaesthetics produced an improvement of the ODI by 9.8% (P < 0.0001). Sarapin resulted in a reduction of NRS by 44% (P = 0.04) and an improvement the ODI by 14.9% (P = 0.004); sarapin combined with steroids promoted a reduction of NRS by 47% (P = 0.04) and an improvement of the ODI by 11.7% (P = 0.001).

CONCLUSION

Injections for chronic LBP deriving from facet joints osteoarthritis are encouraging, especially when considering MBB.

LEVEL OF EVIDENCE

I, systematic review of RCTs.

Uncovering the secretome of mesenchymal stromal cells exposed to healthy, traumatic, and degenerative intervertebral discs: a proteomic analysis

BACKGROUND

Mesenchymal stromal cells (MSCs) have been introduced as promising cell source for regenerative medicine. Besides their multilineage differentiation capacity, MSCs release a wide spectrum of bioactive factors. This secretome holds immunomodulatory and regenerative capacities. In intervertebral disc (IVD) cells, application of MSC secretome has been shown to decrease the apoptosis rate, induce proliferation, and promote production of extracellular matrix (ECM). For clinical translation of secretome-based treatment, characterization of the secretome composition is needed to better understand the induced biological processes and identify potentially effective secretomes.

METHODS

This study aimed to investigate the proteome released by bone marrow-derived MSCs following exposure to a healthy, traumatic, or degenerative human IVD environment by mass spectroscopy and quantitative immunoassay analyses. Exposure of MSCs to the proinflammatory stimulus interleukin 1β (IL-1β) was used as control.

RESULTS

Compared to MSC baseline secretome, there were 224 significantly up- or downregulated proteins following healthy, 179 following traumatic, 223 following degenerative IVD, and 160 proteins following IL-1β stimulus. Stimulation of MSCs with IVD conditioned media induced a more complex MSC secretome, involving more biological processes, compared to stimulation with IL-1β. The MSC response to stimulation with IVD conditioned medium was dependent on their pathological status.

CONCLUSIONS

The MSC secretome seemed to match the primary need of the IVD: homeostasis maintenance in the case of healthy IVDs, versus immunomodulation, adjustment of ECM synthesis and degradation disbalance, and ECM (re) organization in the case of traumatic and degenerative IVDs. These findings highlight the importance of cell preconditioning in the development of tailored secretome therapies. The secretome of human bone marrow-derived mesenchymal stromal cells (MSCs) stimulated with intervertebral disc (IVD) conditioned medium was analyzed by proteomic profiling. Depending on the pathological state of the IVD, the MSC secretome protein composition indicated immunomodulatory or anabolic activity of the secretome. These findings may have implications for tailored secretome therapy for the IVD and other tissues.

Core decompression isolated or combined with bone marrow-derived cell therapies for femoral head osteonecrosis

Objectives: The regenerative capabilities of bone marrow-derived cell therapies (BMCTs) have been employed in combination with core decompression (CD) in the management of osteonecrosis of the femoral head to prevent or delay the necessity of total hip arthroplasty (THA).Methods: The authors conducted a meta-analysis to compare the results of level of evidence I trials comparing CD with and without BMCTs.Results: Overall, 579 procedures were analyzed: 265 in the CD group and 263 in the CD + BMCTs group. Comparability concerning age and gender, drill size, etiology, and grade of OFNH was found (P > 0.1). At a mean follow up of 82.29 (24 to 360) months, the VAS scored favourably for the CD + BMCTs group (mean difference: -12.88; P < 0.0001), as well the rate of THA (odd ratio: -0.14; P < 0.0001). Time to failure (P = 0.4) and to THA (P = 0.9) was similar between the two groups, as was the rate of failure (P = 0.3).Conclusion: In patients with femoral head osteonecrosis, core decompression combined with BMCTs demonstrated reduced pain and lower rate of total hip arthroplasty compared to core decompression as an isolated procedure.

6-gingerol protects nucleus pulposus-derived mesenchymal stem cells from oxidative injury by activating autophagy

BACKGROUND

To date, there has been no effective treatment for intervertebral disc degeneration (IDD). Nucleus pulposus-derived mesenchymal stem cells (NPMSCs) showed encouraging results in IDD treatment, but the overexpression of reactive oxygen species (ROS) impaired the endogenous repair abilities of NPMSCs. 6-gingerol (6-GIN) is an antioxidant and anti-inflammatory reagent that might protect NPMSCs from injury.

AIM

To investigate the effect of 6-GIN on NPMSCs under oxidative conditions and the potential mechanism.

METHODS

The cholecystokinin-8 assay was used to evaluate the cytotoxicity of hydrogen peroxide and the protective effects of 6-GIN. ROS levels were measured by 2´7´-dichlorofluorescin diacetate analysis. Matrix metalloproteinase (MMP) was detected by the tetraethylbenzimidazolylcarbocyanine iodide assay. TUNEL assay and Annexin V/PI double-staining were used to determine the apoptosis rate. Additionally, autophagy-related proteins (Beclin-1, LC-3, and p62), apoptosis-associated proteins (Bcl-2, Bax, and caspase-3), and PI3K/Akt signaling pathway-related proteins (PI3K and Akt) were evaluated by Western blot analysis. Autophagosomes were detected by transmission electron microscopy in NPMSCs. LC-3 was also detected by immunofluorescence. The mRNA expression of collagen II and aggrecan was evaluated by real-time polymerase chain reaction (RT-PCR), and the changes in collagen II and MMP-13 expression were verified through an immunofluorescence assay.

RESULTS

6-GIN exhibited protective effects against hydrogen peroxide-induced injury in NPMSCs, decreased hydrogen peroxide-induced intracellular ROS levels, and inhibited cell apoptosis. 6-GIN could increase Bcl-2 expression and decrease Bax and caspase-3 expression. The MMP, Annexin V-FITC/PI flow cytometry and TUNEL assay results further confirmed that 6-GIN treatment significantly inhibited NPMSC apoptosis induced by hydrogen peroxide. 6-GIN treatment promoted extracellular matrix (ECM) expression by reducing the oxidative stress injury-induced increase in MMP-13 expression. 6-GIN activated autophagy by increasing the expression of autophagy-related markers (Beclin-1 and LC-3) and decreasing the expression of p62. Autophagosomes were visualized by transmission electron microscopy. Pretreatment with 3-MA and BAF further confirmed that 6-GIN-mediated stimulation of autophagy did not reduce autophagosome turnover but increased autophagic flux. The PI3K/Akt pathway was also found to be activated by 6-GIN. 6-GIN inhibited NPMSC apoptosis and ECM degeneration, in which autophagy and the PI3K/Akt pathway were involved.

CONCLUSION

6-GIN efficiently decreases ROS levels, attenuates hydrogen peroxide-induced NPMSCs apoptosis, and protects the ECM from degeneration. 6-GIN is a promising candidate for treating IDD.

Ozone injection therapy for intervertebral disc herniation

INTRODUCTION

Lumbar disc herniation (LDH) is a common cause of low back pain (LBP). Recently, in the setting of LBP caused by LDH, a growing interest in ozone therapies has been observed.

SOURCE OF DATA

Recent published literatures.

AREAS OF AGREEMENT

Being low back pain more common in the elderlies, exploring conservative alternatives to the surgical intervention is of especial interest.

AREAS OF CONTROVERSY

Efficacy and feasibility of ozone injections for LDH is debated. Several clinical studies showed controversial results, and the true benefit has not yet been clarified.

GROWING POINTS

Systematically summarize current evidences, analyze the quantitative available data and investigate the role of percutaneous ozone therapy for LDH.

AREAS TIMELY FOR DEVELOPING RESEARCH

Current evidence encourage the use of ozone therapy for LBP from LDH. These conclusions should be interpret in light of the limitations of the present study.

The pharmacological management of chronic lower back pain

INTRODUCTION

Treating chronic low back pain (LBP) can be challenging, and the most effective pharmacological therapy is controversial. The present systematic review investigated the efficacy of various pharmacological compounds to achieve pain relief and improve disability in chronic LBP patients. The present study focused on acetaminophen, amoxicillin, flupirtine, baclofen, tryciclic antidepressants (TCAs), duloxetine, topiramate, gabapentinoids, non-steroid anti-inflammatory drugs (NSAIDs) and opioids.

AREAS COVERED

All randomized clinical trials comparing two or more drug treatments for chronic low back pain were accessed. Studies reporting outcomes concerning patients with neurologic or mechanic, specific or aspecific low back pain with or without radiculopathy were included. LBP was considered chronic if pain had lasted more than 6 weeks. Data from 47 articles (9007 patients: mean age: 52.62 ± 7.0 years; mean BMI: 28.26 ± 2.8; mean follow-up: 3.23 ± 3.2 months) were obtained.

EXPERT OPINION

According to published level I evidence, only baclofen, duloxetine, NSAIDs, and opiates showed to improve pain and disability levels in patients with LBP. However, the patients' demographics are heterogeneous, and the results must be interpreted with caution and in the light of possible adverse events connected to the use of these drugs.

Lumbar Discitis and Osteomyelitis After a Spinal Stem Cell Injection?: A Case Report and Literature Review

CASE

A 32-year-old man developed lumbar discitis and osteomyelitis after receiving a cell-based injection for the treatment of degenerative disc disease. Initial cultures were negative, but he continued to worsen, and a repeat set of cultures was taken. On day 10, Cutibacterium acnes was isolated. He was then successfully treated with 12 weeks of intravenous antibiotics.

CONCLUSIONS

There is minimal regulation on the preparation or administration of cell-based interventions. It is important to consider slow growing organisms such as C. acnes in patients presenting with spinal infection with insidious onset after these treatments.

The impact and distinction of 'lipid healthy but obese' and 'lipid abnormal but not obese' phenotypes on lumbar disc degeneration in Chinese

Background

Lipid abnormality and obesity have been proposed to be associated with lumbar disc degeneration, but little is known about the effect of ‘lipid healthy but obese’ (LH-O) and ‘lipid abnormal but not obese’ (LA-NO) phenotypes on lumbar disc degeneration in Chinese. The study aims to determine the impact and distinction of LH-O and LA-NO phenotypes on lumbar disc degeneration in Chinese, and to identify the association of related factors with risk of lumbar disc degeneration.

Methods

A total of 678 individuals were included with lumbar magnetic resonance imaging, serum lipid levels and anthropometric measurements. Obesity was defined on the basis of body mass index or waist to hip ratio (WHR). Pfirrmann score and Weishaupt’s scale were utilized to assess the degree of disc degeneration and facet joint degeneration.

Results

The incidence of the LH-O and LA-NO phenotypes were 11.4% and 18.1%, respectively. LA-NO phenotype demonstrates a high incidence for disc degeneration (P < 0.05), while LH-O phenotype confers a severe disc degeneration grade (P < 0.05). No statistical difference in the percentage of severe facet joint degeneration grade in each group (P > 0.05). Elevated triglycerides and greater WHR may be the risk factors for lumbar disc degeneration in Chinese.

Conclusion

LH-O and LA-NO phenotypes are common with different status of disc degeneration in Chinese. Elevated triglycerides and abdominal obesity appear to play crucial roles in the development of lumbar disc degeneration.

Stem cell therapy in pain medicine

Stem cells are attracting attention as a key element in future medicine, satisfying the desire to live a healthier life with the possibility that they can regenerate tissue damaged or degenerated by disease or aging. Stem cells are defined as undifferentiated cells that have the ability to replicate and differentiate themselves into various tissues cells. Stem cells, commonly encountered in clinical or preclinical stages, are largely classified into embryonic, adult, and induced pluripotent stem cells. Recently, stem cell transplantation has been frequently applied to the treatment of pain as an alternative or promising approach for the treatment of severe osteoarthritis, neuropathic pain, and intractable musculoskeletal pain which do not respond to conventional medicine. The main idea of applying stem cells to neuropathic pain is based on the ability of stem cells to release neurotrophic factors, along with providing a cellular source for replacing the injured neural cells, making them ideal candidates for modulating and possibly reversing intractable neuropathic pain. Even though various differentiation capacities of stem cells are reported, there is not enough knowledge and technique to control the differentiation into desired tissues in vivo. Even though the use of stem cells is still in the very early stages of clinical use and raises complicated ethical problems, the future of stem cells therapies is very bright with the help of accumulating evidence and technology.

Knockdown of miR-222 inhibits inflammation and the apoptosis of LPS-stimulated human intervertebral disc nucleus pulposus cells

It has been demonstrated that miR‑222 is upregulated in human intervertebral disc (IVD) degeneration tissues; however, the underlying mechanisms remain unclear. In this study, we aimed to elucidate the mechanisms of action of miR‑222 in IVD tissues. Nucleus pulposus (NP) cells were treated with lipopolysaccharide (LPS) to simulate IVD degeneration. The expression level of miR‑222 was detected by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) in cells and tissues. Cell apoptosis was analyzed by flow cytometry. Additionally, western blot analysis was used to determine the levels of Toll‑like receptor 4 (TLR4), Iκβ‑alpha (IκBα) and p65. Interleukin (IL)‑1β, tumor necrosis factor‑α (TNF‑α) and IL‑6 protein expression levels were determined by enzyme‑linked immunosorbent assay (ELISA). The target gene of miR‑222 was determined by TargetScan7.2 and dual luciferase reporter gene analysis. Western blot analysis and RT‑qPCR were used to determine the mRNA and protein levels of tissue inhibitor of metalloproteinase 3 (TIMP3). The mRNA expression level of miR‑222 was found to be increased in IVD tissues and in LPS‑stimulated cells, and its expression was positively associated with the clinical MRI grade. In vitro, apoptosis was promoted/inhibited by miR‑222 mimics/inhibitors. Transfection with miR‑222 mimics/inhibitors significantly increased/decreased the production of TNF‑α, IL‑1β and IL‑6 and suppressed/enhanced collagen II and aggrecan expression. The protein levels of TLR4, p‑IκΒα and p‑p65 were upregulated/downregulated by transfection with the mimics/inhibitors. In addition, it was demonstrated that TIMP3 was a direct target gene of miR‑222, and was negatively regulated by miR‑222 in NP cells. The silencing of TIMP3 reversed the inhibitory effects of miR‑222 inhibitor on cell apoptosis, which was induced by LPS. Thus, on the whole, the findings of this study demonstrate that miR‑222 functions as a promoter of IVD development, partly via the regulation of TIMP3.

Surgical management for recurrent patellar dislocations in skeletally immature patients

BACKGROUND

Due to his multifactorial aetiology, treating patellofemoral instability can be a challenge for the orthopaedic surgeon. The incidence of patellofemoral instability shows a peak during adolescence, especially from 11 to 14 years old.

AIM

Several clinical studies focusing on recurrent patellar dislocations in skeletally immature patients have been published, reporting inconsistent or controversial results. Currently, there is a lack of consensus regarding the surgical management of these patients. The purpose of this study is to update current evidence and systematically review indications, treatments, and outcomes of surgical management for recurrent patellar dislocations in skeletally immature patients.

METHODS

A comprehensive review of the literature was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis, the PRISMA Statement. The following electronic databases were accessed in February 2019: PubMed, Scopus, Google Scholar, CINAHL, EMBASE. All the articles treating surgical management for recurrent patellar dislocations in skeletally immature patients were considered for inclusion. For the methodological quality assessment, we referred to the Coleman Methodology Score (CMS). For the statistical analysis, we referred to the unpaired t-test to establish whether the results are statistically significant.

RESULT

The overall CMS resulted in 52.78 points, attesting a satisfactory methodological quality assessment to this systematic review. A total of 21 articles including 623 patients (577 knees) were evaluated. The overall mean age was 13.02 years. The mean follow-up was 46.61 months. The mean Kujala score improved from 58.94 ± 10.38 to 87.07 ± 7.68 points. The Lysholm score reported a pre- and post-operative mean values of 49.54 ± 14.20 and 88.32 ± 8.80, respectively. The mean Tegner Activity Scale scored 4.28 ± 1.22 at baseline, improving to 5.26 ± 0.83 post-operatively. A total of 4.19% of patients incurred into a major complication, while 9.6% sustained a minor one. We observed a total of 89 re-dislocations above 692 treated knees (12%).

CONCLUSION

The main findings of this study are that surgical procedures for skeletally immature patients affected by recurrent patellar dislocations are feasible and effective. Complications and re-dislocations occurred infrequently. It is of fundamental importance to treat precociously these patients in order to reduce the risk of further recurrences, to increase the level of sporting activity and improving the quality of life.