Spontaneous regression of lumbar disc herniation: four cases report and review of the literature.

Spontaneous regression of lumbar disc herniation refers to shrinkage or disappearance of herniated nucleus pulposus without invasive surgical treatments. This phenomenon has been reported and is supported by improved clinical symptoms and radiographic after conservative treatment, but the underlying mechanism remains unclear. This article reports 4 cases of disc reabsorption and reviews the distribution of several clinical and radiographic factors of disc herniation reabsorption of total 46 patients, including the four from our study, gathered from 28 recent publications. Some of these factors are present with anomalous distributions. But some factors have similar deviations in patients with lumbar disc herniation. Therefore, more research is needed to explore the correlation between those factors and disc reabsorption.

Global hotspots and future directions for drugs to improve the skin flap survival: A bibliometric and visualized review.

Skin flaps are frequently employed in plastic and reconstructive surgery to address tissue defects. However, their low survival rates remain a challenge, attributed to vascular crisis and necrosis. Despite numerous studies investigating drugs to alleviate flap necrosis, a comprehensive analysis of the research trend in this critical area is lacking. To gain a deeper understanding of the current status, research focal points, and future trends in drugs aimed at enhancing flap survival, a thorough retrospective analysis is imperative. This study aims to employ bibliometric methods to scrutinize the evolution, mechanisms, and forthcoming trends of drugs targeting flap survival improvement. Using VOSviewer software, we quantitatively and visually depict 1) annual temporal trends in the number of documents and citations; 2) national/regional publications and their collaborations; 3) institutional and authors' contribution; 4) journal contribution and relevance; and 5) analysis of research hotspots and directions derived from keywords. Ultimately, we discussed the prospects and challenges of future advances and clinical translation of drugs designed to enhance skin flap survival. In conclusion, the field of pharmacology dedicated to improving skin flap survival is expanding, and this study aims to offer a fresh perspective to promote the advancement and clinical application of such drugs.

Effect of snoring on pregnant women and fetal outcomes: a cross sectional study.

PURPOSE: Snoring frequently occurs among pregnant women, particularly in the later stages of pregnancy. It often signals obstructive sleep apnea (OSA), which could potentially affect pregnancy outcomes negatively. Hence, our study aimed to investigate how snoring influences the likelihood of pregnancy complications and fetal outcomes in a cohort of expectant mothers. METHODS: We enrolled pregnant women in their second and third trimesters and had them fill out a questionnaire concerning sleep-related symptoms such as snoring, excessive daytime sleepiness, and frequency of nighttime awakenings, along with anthropometric measurements. Subsequently, the participants were divided into snorers and non-snorers, and the occurrence of pregnancy complications and fetal outcomes was monitored. RESULTS: The study enrolled a total of 212 pregnant women, among whom 35 were identified as snorers and 177 as non-snorers during mid to late pregnancy. This indicated a snoring prevalence of 16.5% in our sample. Significant differences were noted between the two groups regarding the occurrence of oligohydramnios (11.43% vs. 2.82%, p = 0.044) and fetal distress (28.57% vs. 8.47%, p = 0.003). Logistic regression analyses revealed that snoring was independently associated with fetal distress (odds ratio [OR] = 4.99, 95% confidence interval [CI] 1.88-13.23, p = 0.001). CONCLUSIONS: Our findings suggest that habitual snoring was the independent risk factor fetal distress after adjusting for potential confounders, indicating that habitual snoring may have a detrimental effect during mid to late pregnancy.

Kinship analysis and pedigree reconstruction by RAD sequencing in cattle.

Kinship and pedigree, used for estimating inbreeding, heritability, selection, and gene flow, are useful for breeding and animal conservation. However, as the size of crossbred populations increases, inaccurate generation and parentage assignment in livestock farms increase. Restriction-site-associated DNA sequencing is a cost-effective platform for single nucleotide polymorphism (SNP) discovery and genotyping. Here, we performed a kinship analysis and pedigree reconstruction for Angus and Xiangxi yellow cattle. A total of 975 cattle, including 923 offspring with 24 known sires and 28 known dams, were sampled and subjected to SNP discovery and genotyping. The identified SNP panel included 7,305 SNPs capturing the maximum difference between paternal and maternal genome information, allowing us to distinguish F1 from F2 generations with 90% accuracy. In conclusion, we provided a low-cost and efficient SNP panel for kinship analyses and the improvement of local genetic resources, which are valuable for breed improvement, local resource utilization, and conservation.

Triglyceride-glucose index and combined indicators: effective indicators for screening NAFLD in snoring patients.

AIMS: Nonalcoholic fatty liver disease (NAFLD) is a common complication in snoring patients, especially in patients with obstructive sleep apnea syndrome (OSA). Triglyceride-glucose (TyG) index was a simple indicator of metabolic status and a surrogate marker of insulin resistance. This study aimed to explore the relationship between NAFLD and TyG index in snoring patients. METHODS: A retrospective study was conducted. The successive snoring patients enrolled in the Sleep Center of the First Affiliated Hospital of Fujian Medical University and had abdominal ultrasonography were included. The clinical characteristics of patients in different quartile TyG groups were compared. The relationship of the TyG index and NAFLD were valued via logistic regression models and restricted cubic spline analysis. The value of TyG index in predicting NAFLD was determined by receiver operating characteristic curve (ROC curve). RESULTS: A total of 463 NAFLD cases were found among the 654 snoring patients. TyG index was a risk factor of NAFLD in snoring patients (OR = 2.38, 95% CI = 1.71-3.36). The risk of NAFLD was much higher in patients with the highest quartile of TyG index (OR = 5.12, 95% CI = 2.85-9.22), compared with the lowest quartile group. Restricted cubic spline (RCS) analysis showed a significant dose-response relationship between TyG index and risk of NAFLD (p for non-linearity < 0.001). A combination of TyG, neck circumference and ESS score presented the acceptable AUC for the detection of NAFLD in snoring patients (0.746, 95% CI 0.701-0.790, p < 0.001). CONCLUSION: The TyG index was a risk factor of NAFLD in snoring patients. A combination of TyG, neck circumferences and ESS score could act as a convenient and effective indicator for screening NAFLD in snoring patients.

The History of Classification Systems for Periprosthetic Femoral Fractures: A Literature Review.

Periprosthetic femoral fractures (PPFFs) following total hip arthroplasty (THA) present a significant clinical challenge due to their increasing incidence with an aging population and evolving surgical practices. Historically, classifications were primarily based on anatomical fracture location, the stability of the implant, and bone quality surrounding the implant. We critically analyzed 25 classification systems, highlighting the emergence and adaptations of key systems such as the Vancouver classification system (VCS) and the Unified classification system (UCS), which are lauded for their simplicity and effectiveness yet require further refinement. VCS, developed in 1995, categorizes fractures based on the site, implant stability, and bone quality, and remains widely used due to its robust applicability across different clinical settings. Introduced in 2014, UCS expands the VCS to encompass all periprosthetic fractures with additional fracture types, aiming for a universal application. Despite their widespread adoption, these systems exhibit shortcomings, including the incomplete inclusion of all PPFF types and the imprecise assessment of implant stability and surrounding bone loss. These gaps can result in misclassification and suboptimal treatment outcomes. This paper suggests the necessity for ongoing improvements in classification systems to include emerging fracture types and refined diagnostic criteria, ensuring that they remain relevant to contemporary orthopedic practices and continue to facilitate the precise tailoring of treatment to patient-specific circumstances. This comprehensive historical review serves as a foundation for future innovations in classification systems, ultimately aiming to standardize PPFF treatment and improve patient prognosis.

Corrigendum: Nanofat lysate ameliorates pain and cartilage degradation of osteoarthritis through activation of TGF-ß-Smad2/3 signaling of chondrocytes.

[This corrects the article DOI: 10.3389/fphar.2023.900205.].

α-ketoglutarate preconditioning extends the survival of engrafted adipose-derived mesenchymal stem cells to accelerate healing of burn wounds.

The application of adipose-derived stem cells (ADSCs) in treating hard-to-heal wounds has been widely accepted, while the short-term survival rate remains an obstacle in stem cell therapy. The aim of this study is to investigate the effect of preconditioning ADSCs with α-ketoglutarate (α-KG) on the healing of acid burn wounds and cell survival within wounds. Preconditioning of ADSCs was performed by treating cells at passage 3 with 3.5 mM DM-αKG for 24 h. Proliferation and migration of ADSCs was examined. An acid burn wound was created on the dorsal skin of mice. Cell suspension of ADSCs (2 × 106 cells/ml), either pre-treated with α-KG or not, was injected subcutaneously around the margin of wound. At 1,4,7,10,14 days after injection, the percentage of wound closure was evaluated. Expression of pro-angiogenic factors, matrix molecules and HIF1-α in pretreated ADSCs or in wounds was evaluated by qRT-PCR and immunohistochemistry staining, respectively. The survival rate of DiO-labelled ADSCs was determined with the in vivo bioluminescent imaging system. Treating with α-KG induced an enhancement in migration of ADSCs, while their proliferation was not affected. Expression of Vegf and Fgf-2 was significantly increased. With injection of pretreated ADSCs, healing of wounds was remarkably accelerated, along with increased ECM deposition and microvessel density. Moreover, pretreatment with α-KG resulted a prolonged survival of engrafted ADSCs was observed. Expression of HIF-1α was significantly increased in ADSCs treated with α-KG and in wounds injected with preconditioned ADSCs. Our results revealed that healing of acid burn wound was accelerated with administration of ADSCs pretreated with α-KG, which induced elevated expression of HIF-1α and prolonged survival of engrafted stem cells.

Ferrostatin-1 Reversed Chronic Intermittent Hypoxia-Induced Ferroptosis in Aortic Endothelial Cells via Reprogramming Mitochondrial Function.

Purpose: Chronic intermittent hypoxia (CIH) related arterial endothelium injury is a common cause of cardiovascular system injury. However, the mechanism still needs to be clarified. In this study, we aimed to clarify the role and mechanism of ferrostatin-1 (Fer-1) in CIH-related rat arterial endothelial cells (ROAEC) ferroptosis. Methods: ROAEC was divided into control group, CIH group, and CIH+ Fer-1 group. Cell viability was detected by cell counting kit 8 kits (CCK8). The apoptotic rate, reactive oxygen species (ROS) levels, Fe2+ levels, and lipid ROS levels were detected by flow cytometry. Malondialdehyde (MDA) levels and nicotinamide adenine dinucleotide (NAD+)/NADH ratio were detected via Elisa kits. The mRNA and protein levels of cystine/glutamate antiporter solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) were detected by qRT-PCR and Western blot. Mitochondrial structure and function were observed by transmission electron microscope (TEM) and mitochondrial membrane potential (MMP). Central carbon metabolism was measured to compare metabolites among each group. Results: After the CIH exposure, ROAEC cell viability decreased; The levels of cell apoptosis, ROS, Fe2+, MDA, and lip ROS increased; The levels of NAD+/NADP ratio decreased; The mRNA and protein levels of GPX4 and SLC7A11 decreased (all p<0.05). Co-cultured with Fer-1 reversed the levels of apoptosis rate, cell viability, ROS, Fe2+, MAD, lipid ROS, NAD+/NADH ratio and the mRNA and protein expression of GPX4 and SLC7A11 (all p<0.05). The TEM results showed that damaged mitochondrial membrane and the matrix spillover in the CIH group. The results of the JC-1 assay showed decreased MMP in the CIH group. Fer-1 treatment ameliorated the mitochondrial injury. The results of central carbon metabolism found that CIH altered the metabolites in the TCA cycle, which were reversed by Fer-1 treatment. Conclusion: CIH-induced ferroptosis in ROAEC, which were reversed by Fer-1 via reprogramming mitochondrial function.

Complete coding genome sequence of a Teschovirus A genotype strain.

This study reports the complete coding genome sequence of a novel Teschovirus A genotype strain, SG2, isolated from the fecal sample of an infected indigenous pig in western Jiangxi, China.

Circular RNA_0025843 Alleviated Cigarette Smoke Extract Induced Bronchoalveolar Epithelial Cells Ferroptosis.

Purpose: Circular RNA (circRNA) plays an important role in various biological processes. However, their functions in cigarette smoke extract (CSE) induced human normal lung epithelial cells (BEAS-2B) injury remain vague. The study aimed to explore circRNA expression profiles and reveal their potential roles in CSE-treated BEAS-2B cells. Methods: 5% CSE exposure for 24 hours were used to build the BEAS-2B cells ferroptosis model. Differentially expressed circRNAs (DECs) were identified by next-generation RNA sequencing. Six randomly selected DECs were validated via quantitative reverse transcription polymerase chain reaction (qRT-PCR). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and Gene Ontology (GO) analysis were conducted to clarify the potential functions of the DECs. Furthermore, the role of hsa_circ_0025843 in CSE-related BEAS-2B cells ferroptosis was confirmed. Results: 5% CSE exposure induced BEAS-2B cells ferroptosis. Fifty-one up-regulated cirRNAs and 80 down-regulated circRNAs were revealed in CSE-treated BEAS-2B cells. Hsa_circ_0003461, hsa_circ_0007548, hsa_circ_0025843, hsa_circ_0068896, hsa_circ_0005832, and hsa_circ_0053378 were selected randomly to validate the reliability of next-generation RNA sequencing by qRT-PCR. After KEGG pathway analysis, DECs were found to participate in the process of EGFR tyrosine kinase inhibitor resistance and glycerophospholipid metabolism. The knockdown of hsa_circ_0025843 significantly alleviated CSE-induced BEAS-2B cells ferroptosis. Conclusion: The study indicated the circRNA expression profiles in CSE-treated BEAS-2B cells. Hsa_circ_0025843 alleviated CSE induced BEAS-2B cells ferroptosis, which might be a potential therapeutic target of CSE related lung injury.

The role of exosomal circular RNA ZNF292 in intermittent hypoxia-induced AC16 cardiomyocytes injury.

BACKGROUND: Exosomes are involved in cell-to-cell communication in numerous diseases including cardiovascular diseases, neurological diseases. Little attention has been dedicated to exosomal circular RNAs in obstructive sleep apnea (OSA)-related cardiovascular diseases. The aim of this study was to explore the role of exosomal circular RNA ZNF292 (circZNF292) on AC16 cells exposure to intermittent hypoxia (IH). METHODS: Exosome release inhibitor GW4869 was used to examine the effect of exosomes on IH-induced AC16 cells apoptosis. The expression of exosomal circZNF292 was detected by qRT-PCR in AC16 cells exposure to IH, and a luciferase reporter assay was conducted to confirm the connection between circZNF292 and miR-146a-5p. Exosomal circZNF292 was stably transfected with short hairpin RNAs (shRNAs) against circZNF292 and co-cultured with AC16 cells. The expression of miR-146a-5p and apoptosis-related protein was then measured to evaluate the effect of exosomal circZNF292. RESULTS: We found that IH contributed to the AC16 cells apoptosis, and the administration of GW4869 increased the apoptosis of cardiomyocytes when exposed to IH. The expression of exosomal circZNF292 decreased and miR-146a-5p increased significantly in AC16 cells exposed to IH compared to normoxic conditions. Bioinformatics analysis predicted a circZNF292/miR-146a-5p axis in IH-induced cardiomyocytes apoptosis. The dual-luciferase reporter system validated the direct interaction of circZNF292 and miR-146a-5p. Knockdown of circZNF292 increased the expressions of miR-146a-5p and accelerated the AC16 cardiomyocytes apoptosis. CONCLUSIONS: The findings of this study suggested a novel mechanism by which exosomes transmit intrinsic regulatory signals to the myocardium through the exosomal circZNF292/miR-146a-5p axis. This finding highlights the potential of targeting this pathway as a therapeutic approach for treating cardiovascular diseases associated with OSA.

Minimally Invasive Treatment of Inversion Shortening Calcaneal Fractures in the "Out-In" Position.

OBJECTIVE: Heel fractures need extensive surgical incisions and are challenging to successfully reposition using traditional prying. The goal of this study is to evaluate the clinical effectiveness of using a Kirschner pin-guided distractor to treat inversion shortening calcaneal fractures in the "out-in" position. METHODS: A total of 40 data from 37 patients with inversion shortened calcaneal fractures from January 2018 to March 2020 were reviewed. Preoperative lateral and axial X-rays and 3D CT were taken to assess the fracture type, and minimally invasive internal fixation was performed in the "out-in" position with distractor repositioning, and intraoperative and postoperative images were taken to assess fracture repositioning and fixation. During the follow-up period, the postoperative functional recovery status was assessed using the VAS score, AOFAS score, and FAOS score. Paired-samples t-test was used for all data comparisons. RESULTS: All cases received a mean follow-up of 28.49 ± 3.25 months, and the mean fracture healing time was 7.84 ± 0.71 weeks. The postoperative images showed well-fixed fracture repositioning, and calcaneal height, length, width, and inversion angles were significantly improved. At the final follow-up, the calcaneal height, length, and width recovered from 39.35 ± 4.44mm, 79.35 ± 2.7mm, and 45.75 ± 2.87mm preoperatively to 50.93 ± 3.18mm, 82.23 ± 1.90mm, and 39.67 ± 1.58mm postoperatively (p < 0.001; p < 0.001; p < 0.001). The calcaneus inversion angle restored from 7.73° ± 2.26° to 3.80° ± 1.80° (p < 0.001). Böhler's angle and Gissane's angle improved from 13.13° ± 3.02° and 105.15° ± 8.94° to 27.95° ± 3.41° and 122.85° ± 5.54° (p < 0.001; p < 0.001). No non-healing fractures, osteomyelitis, or traumatic arthritis were observed. CONCLUSION: Minimally invasive internal fixation with distractor repositioning in the "out-in" position is effective in the treatment of inversion shortening calcaneal fractures while restoring the anatomy and protecting the soft tissue.

Surgical treatment of specific Unified Classification System B fractures: potentially destabilising lesser trochanter periprosthetic fractures.

To investigate the clinical effects of specific Unified Classification System B (UCS B)-lesser trochanter periprosthetic fractures and determine whether they occur only with non-cemented stems. A retrospective analysis of 28 patients with specific UCS B2 fractures who underwent two surgical treatments, longer stem revision and internal fixation (LSRIF) and open reduction and internal fixation (ORIF), was performed. The patients were assessed at 1, 3, 6, 12, and 24 months and annually thereafter. Fracture healing, complications, Harris Hip Score (HHS), and the Short Form Health Survey questionnaire (SF-36) quality of life score were assessed at each follow-up. At the time of the last follow-up, seven patients had been lost: three were lost to contact, two died, and two were hospitalised elsewhere and unavailable for follow-up. The remaining 21 patients were followed for an average of 49.3 ± 15.4 (range: 24-74.4) months. Their average fracture healing time was 13.5 ± 1.1 (12-15.4) weeks. Complications included three cases (10.71%) of thrombus, one (3.57%) of heart failure, and one (3.57%) of pulmonary infection. There were no revisions due to prosthesis loosening, subsidence, or infection. At the last follow-up, the HHS, SF-36 mental score, and SF-36 physical score were recorded, LSRIF vs. ORIF (82.9 ± 6.6 vs. 74.7 ± 3.9, p = 0.059; 50.9 ± 7.6 vs. 38 ± 1.4, p = 0.012, and 51.7 ± 8.4 vs. 39.7 ± 3.4, p = 0.032, respectively). Specific UCS B2 fractures mostly occur with non-cemented stems. LSRIF with cables is the main treatment, while ORIF is an option for those elderly in poor condition.

A Novel Platform of MOF for Sonodynamic Therapy Advanced Therapies.

Metal-organic frameworks (MOFs) combined with sonodynamic therapy (SDT) have been introduced as a new and efficient treatment method. The critical advantage of SDT is its ability to penetrate deep tissues and concentrate energy on the tumor site to achieve a non-invasive or minimally invasive effect. Using a sonosensitizer to generate reactive oxygen species (ROS) under ultrasound is the primary SDT-related method of killing tumor cells. In the presence of a sonosensitizer, SDT exhibits a more lethal effect on tumors. The fast development of micro/nanotechnology has effectively improved the efficiency of SDT, and MOFs have been broadly evaluated in SDT due to their easy synthesis, easy surface functionalization, high porosity, and high biocompatibility. This article reviews the main mechanism of action of sonodynamic therapy in cancer treatment, and also reviews the applications of MOFs in recent years. The application of MOFs in sonodynamic therapy can effectively improve the targeting ability of SDT and the conversion ability of reactive oxygen species, thus improving their killing ability on cancer cells. This provides new ideas for the application of micro/nano particles in SDT and cancer therapy.

Reverse traction with Kirschner wires and bilateral external fixation device combined with minimally invasive plate oseoynthesis technique for tibial plateau fractures of type Schatzker V and VI.

PURPOSE: Complex bicondylar tibial plateau fracture (TPF) has always been a tricky problem for surgeons. We created a novel external device used intraoperatively consisting of Kirschner wires, and combined with minimally invasive plate oseoynthesis (MIPO) technique to treat complex bicondylar TPFs, and the clinical effect and feasibility were further evaluated. METHODS: From March 2016 to February 2021, 49 cases (29 males and 20 females) were identified as bicondylar TPF, the mean age 47.2 (27-69). All patients adopted the device and MIPO technique. A series of score, complications, and radiographs in the follow-up period, from three months, six months, one year, and two years and the last follow-up, were recorded, from visual analogue score (VAS), hospital for special surgery (HSS), and Short-Form 36 (SF-36), containing physical (PCS) and mental (MCS), and Rasmussen score. RESULTS: Forty-seven patients showed good functional recovery. No patients were lost, mean follow-up time was 28.17 ± 2.81 (24.2-35.4) months. Operation time was 89.80 ± 13.46 (58-110) min. At the last follow-up, VAS was 1.3 ± 0.92 (0-4), HHS was 93.10 ± 2.63 (89-99), PCS was 49.20 ± 7.40 (38-65), and MCS was 50.08 ± 4.77 (43-62). Complications were as follows: cutaneous necrosis (3, 6%), asymptomatic arthritis (3, 6%), symptomatic arthritis (1, 2%), and deep venous thrombosis (1, 2%). Mean fracture healing time was 11.82 ± 1.5 (10-15.4) weeks. All patients got recovery without extra surgery and removed the implants at 12.85 ± 0.76 (11.2-15.4) months. CONCLUSION: Temporary traction device of bilateral external fixator combined with MIPO technique was simple and convenient, with a smaller soft-tissue damage, an easier operational approach, and its worth being promoted.

Metal-organic frameworks (MOFs) as apt luminescent probes for the detection of biochemical analytes.

The detection of active substances in the body is very important for good human health as it gives important insights into the smooth functioning of the body. Most of the conventional materials that can be used as suitable probes require complicated fabrication methodologies, have poor stability and are susceptible to environmental effects. In contrast, metal-organic frameworks (MOFs) offer unique advantages as probes for testing analytes due to their tunable porosity, good specific surface area and ease of modification. Unlike previously reported perspectives/reviews, this perspective focuses on the latest applications of MOFs as detection materials for hydrogen peroxide, various metal ions, hydrogen sulfide, organic small molecules, glutathione, and organic macromolecules such as nucleic acids, and focuses on providing a more detailed mechanism of action. Also, the basic principles of action utilized by this class of materials are discussed.

Early surgical treatment of closed reduction and internal fixation for a 30-day old intertrochanteric fracture with hemiplegia after acute stroke: A case report.

RATIONALE: Currently, there are no clear guidelines to determine whether and when to perform surgical hip repair in patients with acute stroke and hip fracture. PATIENT CONCERNS: In this case report, we report a case of 75-year-old woman admitted with left hip pain and limited mobility for 1 month. DIAGNOSES: Patient had a history of acute cerebral infarction 42 days ago, and diagnosed with a left intertrochanteric fracture at another hospital 30 days ago. INTERVENTION: Patient was treated with closed reduction and internal fixation with proximal femoral nail anti-rotation. OUTCOMES: At 2-year follow-up, the patient's basic function was restored. The fracture healed well, and the Harris hip score was 75. LESSONS: Without consistent guidelines, individualized treatment strategies including surgical methods and timing of surgery should be made to weigh the risks and benefits for patients with acute stroke and intertrochanteric fractures.

Detrimental alteration of mesenchymal stem cells by an articular inflammatory microenvironment results in deterioration of osteoarthritis.

BACKGROUND: Articular injection of mesenchymal stem cells (MSCs) has been applied to treat knee osteoarthritis (kOA), but its clinical outcomes are controversial. This study investigated whether an articular inflammatory microenvironment (AIM) impacts MSC-based therapy in a rat model of kOA. METHODS: The biological change of MSCs and the functional change of MSCs on chondrocytes were evaluated under AIM. The key mediator and mechanism for the AIM impact on MSC therapy were explored via gain- and loss-of-function approaches. RESULTS: The results showed that MSCs exerted potent anti-kOA effects in vivo and in vitro, but that this therapy become chondrodestructive if a chronic AIM was present. Mechanistically, the overexpression of MMP13 in the injected MSCs via a MAPKs-AP1 signaling axis was revealed as the underlying mechanism for the detriment outcome. CONCLUSIONS: This study thus clarifies recent clinical findings while also suggesting a means to overcome any detrimental effects of MSC-based therapy while improving its efficacy.