Increased prevalence of metabolic syndrome in individuals with osteoarthritis: an analysis of NHANES III data

Metabolism-Related Adipokines and Metabolic Diseases: Their Role in Osteoarthritis

Osteoarthritis (OA) affects several joints but tends to be more prevalent in those that are weight-bearing, such as the knees, which are the most heavily loaded joints in the body. The incidence and disability rates of OA have continued to increase and seriously jeopardise the quality of life of middle-aged and older adults. However, OA is more than just a wear and tear disease; its aetiology is complex, and its pathogenesis is poorly understood. Metabolic syndrome (MetS) has emerged as a critical driver of OA development. This condition contributes to the formation of a distinct phenotype, termed metabolic syndrome-associated osteoarthritis (MetS-OA),which differs from other metabolically related diseases by its unique pathophysiological mechanisms and clinical presentation. As key mediators of MetS, metabolic adipokines such as leptin, lipocalin, and resistin regulate inflammation and bone metabolism through distinct or synergistic signaling pathways. Their modulation of inflammatory responses and bone remodeling processes plays a critical role in the pathogenesis and progression of OA. Due to their central role in regulating inflammation and bone remodeling, metabolic adipokines not only deepen our understanding of MetS-OA pathogenesis but also represent promising targets for novel therapeutic strategies that could slow disease progression and improve clinical outcomes in affected patients.

Genetic Links Between Metabolic Syndrome and Osteoarthritis: Insights From Cross-Trait Analysis

CONTEXT

Previous observational studies have indicated a bidirectional association between metabolic syndrome (MetS) and osteoarthritis (OA). However, it remains unclear whether these bidirectional associations reflect causal relationships or shared genetic factors, and the underlying biological mechanisms of this association are not fully understood.

OBJECTIVE

We aimed to explore the genetic connection between MetS and OA using genome-wide association study (GWAS) summary data.

METHODS

Leveraging summary statistics from GWAS conducted by the UK Biobank and the Glucose and Insulin-related Traits Consortium (MAGIC), we performed global genetic correlation analyses, genome-wide cross-trait meta-analyses, and a bidirectional two-sample Mendelian randomization analyses using summary statistics from GWAS to comprehensively assess the relationship of MetS and OA.

RESULTS

We first detected an extensive genetic correlation between MetS and OA (rg = 0.393, P = 1.52 × 10-18), which was consistent in 4 MetS components, including waist circumference, triglycerides, hypertension, and high-density lipoprotein cholesterol and OA with rg ranging from -0.229 to 0.490. We then discovered 32 variants jointly associated with MetS and OA through Multi-Trait Analysis of GWAS (MTAG). Co-localization analysis found 12 genes shared between MetS and OA, with functional implications in several biological pathways. Finally, Mendelian randomization analysis suggested genetic liability to MetS significantly increased the risk of OA, but no reverse causality was found.

CONCLUSION

Our results illustrate a common genetic architecture, pleiotropic loci, as well as causality between MetS and OA, potentially enhancing our knowledge of high comorbidity and genetic processes that overlap between the 2 disorders.

Associations between surrogate insulin resistance indexes and osteoarthritis: NHANES 2003-2016

Insulin resistance (IR) and abdominal obesity are key in osteoarthritis (OA) development. The triglyceride glucose (TyG) index, along with indicators such as the visceral adiposity index (VAI), and lipid accumulation product (LAP), are increasingly used to measure IR. This study aims to explore the associations between surrogate IR indexes and OA, assessing their diagnostic efficacy within American populations. This study included 14,715 adults from the National Health and Nutrition Examination Survey 2003-2016. Logistic regression models and restricted cubic spline were used to explore the relationship between surrogate IR indexes and OA. Receiver operating characteristic curves were constructed to assess the diagnostic efficacy of these indices, with the area under the curve (AUC) as the metric. TyG, glucose triglyceride-waist circumference (TyG-WC), glucose triglyceride-body mass index (TyG-BMI), glucose triglyceride-waist height ratio (TyG-WHtR), VAI and LAP were significantly and positively associated with the prevalence of OA (all p < 0.01). After adjusting for various potential confounders, TyG-WC, TyG-BMI, TyG-WHtR and LAP remained significantly correlated with the prevalence of OA. Furthermore, restricted cubic spline revealed a nonlinear association between TyG-BMI, TyG-WHtR and LAP (all P-non-linear < 0.05). Receiver operating characteristic curves indicated that TyG-WHtR (AUC 0.633) demonstrated more robust diagnostic efficacy. Additionally, the sensitivity analysis produced results consistent with the primary findings. TyG and its combination with obesity indicators and LAP, are positively associated with the prevalence of OA, with TyG-WHtR showing the highest diagnostic efficacy.

Genetic insights into the risk of hip osteoarthritis on stroke: A single-variable and multivariable Mendelian randomization

BACKGROUND

Hip osteoarthritis has been identified as a potential risk factor for stroke, with previous studies have demonstrated an association between hip osteoarthritis and stroke. This study aims to further elucidate the causal relationship between the two, employing Two-Sample and Multivariable Mendelian randomization methods.

METHODS

SNPs, derived from two extensive GWAS, served as instruments in exploring the association between genetically predicted hip osteoarthritis and stroke risk, utilizing two-sample Mendelian randomization. In Multivariable Mendelian randomization, factors such as cigarettes per day, alcoholic drinks per week, hypertension, body mass index, type 2 diabetes, C-reactive protein, rheumatoid arthritis were incorporated to further account for the independent causal effects of multiple correlated exposures.

RESULTS

Two-sample Mendelian randomization analysis revealed that hip osteoarthritis exerts a potential causal effect on any stroke, any ischemic stroke, and cardioembolic stroke, while it did not influence large artery stroke and small vessel stroke. Multivariable MR analysis indicated that the causal effect of hip osteoarthritis on any ischemic stroke and cardioembolic stroke was no longer evident after adjusting for C-reactive protein, and similarly, the effect on any ischemic stroke was not observed after adjusting for type 2 diabetes. However, the effects on any stroke, any ischemic stroke, and cardioembolic stroke remained significant after adjustments for hypertension, alcoholic drinks per week, cigarettes per day, body mass index, and rheumatoid arthritis.

CONCLUSION

The study demonstrated that elevated hip osteoarthritis, as predicted by genetic factors, was potential associated with an increased risk of any stroke, any ischemic stroke, and cardioembolic stroke, but showed no correlation with hypertension, alcoholic drinks per week, cigarettes per day, type 2 diabetes, C-reactive protein, body mass index levels, and rheumatoid arthritis.

The genetic and observational nexus between diabetes and arthritis: a national health survey and mendelian randomization analysis

BACKGROUND

Diabetes mellitus (DM) and arthritis are prevalent conditions worldwide. The intricate relationship between these two conditions, especially in the context of various subtypes of arthritis, remains a topic of interest.

OBJECTIVE

To investigate the relationship between diabetes and arthritis, with a focus on Rheumatoid Arthritis (RA), using data from the National Health and Nutrition Examination Survey (NHANES) and Mendelian Randomization (MR) analysis.

METHODS

Data from six consecutive NHANES cycles from 2007 to 2018 were analyzed, involving 30,062 participants after applying exclusion criteria. The association between diabetes and arthritis was assessed using logistic regression. MR was employed to determine the causal relationship between the two conditions using Genome-Wide Association Study (GWAS) data.

RESULTS

The prevalence of arthritis in diabetic patients was almost twice that of non-diabetic patients. Logistic regression showed a significant gross association between arthritis and diabetes with an OR of 2.90 (95% CI: 2.66-3.16). After adjusting for age, gender, race, and other factors, the association yielded an OR of 1.14 (95% CI: 1.00-1.29, p < 0.05). MR analyses indicated a significant association between Type 1 Diabetes and RA (OR = 1.407, p = 0.002), but no significant correlation was observed for Type 2 Diabetes.

CONCLUSION

There is an association between diabetes and arthritis, with potential genetic links between Type 1 Diabetes and RA.

HDL-C is inversely associated with the incidence of osteoarthritis among the USA: evidence from the NHANES program of 1999-2020

Osteoarthritis (OA) has been the most common arthritis affecting public health all over the world. Previous experimental research reported that increased low-density lipoprotein cholesterol, along with decreased high-density lipoprotein cholesterol may be associated with increased ectopic bone formation and possible knee OA, while clinical evidence is absent. This study aimed to investigate the association between blood high-density lipoprotein cholesterol (HDL-C) and OA. In this cross-sectional study, all the data were acquired from the National Health and Nutrition Examination Survey (NHANES) program from 1999 to 2020. The blood lipid metabolites of each participant were acquired from the laboratory data, using the standard approach. The diagnosis of OA was established through a questionnaire interview. The multivariate logistic regression analysis, subgroup analysis, and smooth curve fitting analysis were applied to investigate the association between the blood lipid metabolites and OA after adjusting with covariates including gender, age, race, BMI, marital status, physical activity, smoking, hypertension, and diabetes. The interaction analysis and Subgroup analysis were also performed. A total of 28,933 participants, including 3710 people with self-reported OA and 25,223 people without arthritis, were finally eligible for inclusion in this study. The multiple logistic regression indicated that in the 3rd and 4th quartiles, the HDL-C level showed a positive association with the risk of OA (Q3: OR = 1.1342, 95% CI 1.0071, 1.2773, p < 0.05; Q4: OR = 1.2354, 95% CI 1.0937, 1.3956, p < 0.001). The smooth curve fitting showed a trend that the OA odds ratio increased with the increase of HDL-C. Subgroup analysis continued to show that increased HDL led to increased OA risk at certain quartiles in different subgroups. This study shows a positive correlation between blood HDL-C levels and osteoarthritis (OA) risk, suggesting HDL-C may be a risk factor. Further research is needed, especially on lipid-lowering drugs like statins, which can affect HDL-C and influence this association.

Associations of 24-hr Movement Behaviors With Cardiometabolic Risk Factors and Metabolic Syndrome in Adults Receiving Outpatient Rehabilitation: A Compositional Time-Use Analysis

BACKGROUND

Research suggests associations between physical activity, sedentary behavior, sleep, and metabolic syndrome, but most has focused on healthy populations and individual behaviors. We investigated associations of 24-hr movement behavior compositions with cardiometabolic risk factors and metabolic syndrome in adults receiving rehabilitation for other health conditions.

METHOD

 This cross-sectional study assessed 24-hr movement behaviors using thigh-worn accelerometers and metabolic outcomes via blood analyses in 145 adults attending outpatient rehabilitation. Regression models tested associations of five 24-hr time-use behaviors (time in bed, sedentary time, standing, light-intensity stepping, and moderate- to vigorous-intensity stepping) with cardiometabolic risk factors and metabolic syndrome severity score (a cumulative measure of risk derived from metabolic risk factors).

RESULTS

 Participants (64 [SD 12] years old; 52% women; 66% with metabolic syndrome, with 6 [SD 0.7] days of 24-hr data) spent 41% of a 24-hr day sedentary, 15% standing, 3% in light-intensity stepping, 2% in moderate- to vigorous-intensity stepping, and 38% in bed. Adjusted models indicated that a higher proportion of light-intensity stepping was associated with lower triglycerides, more time in bed was associated with a higher metabolic syndrome severity score, and more time stepping was associated with a lower metabolic syndrome severity score. There was no evidence of associations between the overall compositions and outcomes.

CONCLUSION

The consistently observed small proportions of physical activity, with lack of variation between participants, may not be sufficient to counteract the impact of high sedentary time on metabolic outcomes in adults attending outpatient rehabilitation.

IMPLICATIONS

 Future research may focus on exploring ways to increase light-intensity stepping in sedentary older adults with various health conditions.

Gut microbiome dysbiosis is associated with lumbar degenerative spondylolisthesis in symptomatic patients

Background

Lumbar degenerative spondylolisthesis (LDS), characterized as degeneration of the intervertebral disc and structural changes of the facet joints, is a condition with varying degrees of instability that may lead to pain, canal stenosis, and subsequent surgical intervention. However, the etiology of LDS remains inconclusive. Gut microbiome dysbiosis may stimulate systemic inflammation in various disorders. However, the role of such dysbiosis upon spine health remains under-studied. The current study assessed the association of gut microbiome dysbiosis in symptomatic patients with or without LDS.

Methods

A cross-sectional analysis within the framework of a prospective study was performed. DNA was extracted from fecal samples collected from adult symptomatic patients with (n = 21) and without LDS (n = 12). Alpha and beta diversity assessed differences in fecal microbial community between groups. Taxon-by-taxon analysis identified microbial features with differential relative abundance between groups. Subject demographics and imaging parameters were also assessed.

Results

There was no significant group differences in age, sex, race, body mass index, smoking/alcohol history, pain profiles, spinopelvic alignment, and Modic changes (p >0.05). LDS subjects had significantly higher disc degeneration severity (p = 0.018) and alpha diversity levels compared to non-LDS subjects (p = 0.002-0.003). Significant differences in gut microbial community structure were observed between groups (p = 0.046). Subjects with LDS exhibited distinct differences at the phylum level, with a significantly higher Firmicutes to Bacteroidota ratio compared to non-LDS (p = 0.003). Differential relative abundance analysis identified six taxa with significant differences between the two groups, with LDS demonstrating an increase in putative pro-inflammatory bacteria (Dialister, CAG-352) and a decrease in anti-inflammatory bacteria (Slackia, Escherichia-Shigella).

Conclusion

This study is the first to report a significant association of gut microbiome dysbiosis and LDS in symptomatic patients, noting pro-inflammatory bacterial taxa. This work provides a foundation for future studies addressing the role of the gut microbiome in association with spine health and disease.

Metabolic syndrome is associated with poorer outcomes in people with osteoarthritis participating in a rehabilitation program: an observational study

PURPOSE

To determine the prevalence of metabolic syndrome and explore its association with clinical outcomes (pain, quality of life, and physical function) in adults participating in an education and exercise program (GLA:D®).

METHODS

An observational study of adults with hip and/or knee osteoarthritis who participated in GLA:D® between 2019 and 2022. Metabolic syndrome status was determined through self-report. Differences in clinical outcomes among people with, at risk of (1-2 risk factors), or without metabolic syndrome were compared at baseline, 3-, and 12-months using linear mixed models (age, sex, and baseline outcomes as covariates).

RESULTS

Of 6846 participants (aged 65(SD 9) years), 20% (n = 1337) had, and 68% (n = 4632) were at risk of metabolic syndrome. Adults with metabolic syndrome reported higher pain (0-100 VAS: 7.3, 95% CI 5.4-9.1), lower health-related quality of life (EQ5D 0-100, VAS: -8.6, 95% CI -10.2 to -7.0), and slower gait speed (-0.26 m/s, 95%CI -0.3 to -0.23) at baseline compared to those with no metabolic risk factors. Differences remained at 3- and 12-months for pain and quality of life.

CONCLUSIONS

Metabolic syndrome risk factors were common in adults with osteoarthritis. Clinical outcomes remain impaired in people with metabolic syndrome compared to those without after education and exercise, suggesting further intervention may be required.

The association between ADAMTS14/rs4747096 gene polymorphism and some risk factors and knee osteoarthritis

Knee osteoarthritis (KOA) is an important cause of disability in the world and it denotes a public health defiance of the upcoming years.Aim To examine the connection between ADAMTS14 gene rs4747096 polymorphism and KOA and to assess risk factors associated with KOA.Methods A case control study was conducted on 158 patients with KOA and 120 controls with comparable age and sex randomly recruited from National Research Centre employees. All participants were subjected to full history taking, assessment of KOA severity using WOMAC scoring system, and thorough clinical examination. Blood sample was collected for detection of ADAMTS14/rs4747096 gene polymorphism.Results The frequency of ADAMTS14 gene rs4747096 genotypes among patients with KOA was 73.5% for AA, 25.7% for AG, and 0.7% for GG compared to controls 963%, 31.3%, and 5.6% respectively and the frequency of alleles among patients was 86.4% for A and 78.7% for G compared to controls (78.7% and 21.3% respectively, P < 0.05. The study found that the median levels of total WOMAC score and its domains were significantly higher among KOA patients than controls. The logistic regression analysis revealed that age ≥ 50 years, BMI ≥ 35, and long standing at work were predictive factors for KOA (P < 0.05). Regarding different genetic patterns, only the A recessive pattern of inheritance was found to be a predictive risk factor for KOA.Conclusion For ADAMTS14 rs4747096 genotype, the AA and AG genotypes significantly increased the risk of KOA. The recessive pattern of inheritance, older age, morbid obesity, and prolonged standing at work were the predictive risk factors for KOA. Further studies with larger sample size are encouraged to investigate the mechanism by which this genotype can affect the development of KOA.

Metabolic syndrome increases the length of stay and medical complications after hip and knee arthroplasty: results from a prospective cohort study of 2,901 patients

BACKGROUND AND PURPOSE

 Metabolic syndrome (MetS) affects more than 60% of the patients having a hip or knee arthroplasty due to osteoarthritis. As it is debated whether metabolic syndrome increases the risk of complications, we aimed to investigate the length of stay (LOS) and risk of readmission at 30 and 90 days after surgery, including causes of readmission.

METHODS

 We conducted a prospective cohort study of 2,901 patients undergoing hip and knee arthroplasty from May 2017 to November 2019. Physical examination, blood samples, and medical history from national registries determined the diagnosis of metabolic syndrome from the International Diabetes Federation definition. We used multivariate linear regression to investigate differences in LOS according to MetS, and binary regression to investigate the risk and causes of readmission within 30 and 90 days, including 95% confidence intervals (CI) and P values.

RESULTS

 Patients with MetS showed a slightly longer LOS (0.20 days, CI 0.10-0.29) and had an increased risk of readmission within 90 days (adjusted relative risk [RR] 1.2, CI 1.0-1.4; P = 0.02), but not within 30 days (adjusted RR 1.1, CI 0.9-1.4; P = 0.3) after surgery. Cardiovascular disease was the dominant cause of readmission.

CONCLUSION

Although patients with MetS do not experience a clinically relevant longer LOS after hip and knee arthroplasty, they have an increased risk of 90-day readmission mainly due to cardiovascular complications, which should be considered when planning surgical care in this group of patients.

Metabolic syndrome and patient-reported outcome two years after hip and knee arthroplasty

Aims

The influence of metabolic syndrome (MetS) on the outcome after hip and knee arthroplasty is debated. We aimed to investigate the change in patient-reported outcome measure (PROM) scores after hip and knee arthroplasty, comparing patients with and without MetS.

Methods

From 1 May 2017 to 30 November 2019, a prospective cohort of 2,586 patients undergoing elective unilateral hip and knee arthroplasty was established in Denmark. Data from national registries and a local database were used to determine the presence of MetS. Patients' scores on Oxford Hip Score (OHS) or Oxford Knee Score (OKS), EuroQol five-dimension five-level questionnaire (EQ-5D-5L), University of California, Los Angeles (UCLA) Activity Scale, and Forgotten Joint Score (FJS) at baseline, three, 12, and 24 months after surgery were collected. Primary outcome was the difference between groups from baseline to 12 months in OHS and OKS. Secondary outcomes were scores of OHS and OKS at three and 24 months and EQ-5D-5L, UCLA Activity Scale, and FJS at three, 12, and 24 months after surgery. Generalized linear mixed model was applied, adjusting for age, sex, Charlson Comorbidity Index, and smoking to present marginal mean and associated 95% CIs.

Results

A total of 62.3% (1,611/2,586) of the cohort met the criteria for MetS. Both groups showed similar increase in mean OHS (MetS group 22.5 (95% CI 21.8 to 23.1), non-MetS group 22.1 (21.3 to 22.8); p = 0.477) and mean OKS (MetS group 18.0 (17.4 to 18.6), non-MetS group 17.8 (17.0 to 18.7); p = 0.722) at 12 months' follow-up. Between groups, similar improvements were seen for OHS and OKS at three and 24 months postoperatively and for the mean EQ-5D-5L, EuroQol-visual analogue scale (EQ-VAS), UCLA Activity Scale, and FJS at every timepoint.

Conclusion

Patients meeting the criteria for MetS obtain the same improvement in PROM scores as individuals without MetS up to 24 months after hip and knee arthroplasty. This is important for the clinician to take into account when assessing and advising patients with MetS.

Metabolic Syndrome and Morbid Obesity are Not Risk Factors for Revision Surgery in Patients Undergoing Hip and Knee Arthroplasty

BACKGROUND

The effect of metabolic syndrome (MetS) on the risk of revision after hip and knee arthroplasty is debated. The aim of our study was to investigate the risk of short-term (minimum 2.7 years) revision due to periprosthetic joint infection (PJI) after hip and knee arthroplasty. Secondly, we aimed to investigate the risk of revision due to any cause and mortality.

METHODS

During May 2017 to November 2019, a cohort of 2,901 patients undergoing a total of 3,024 hip and knee arthroplasties was established. In the cohort, 62.1% met the criteria for MetS. Data from national registries and a local database were used to determine the presence of MetS and revision surgeries, with a follow-up of at least two years and eight months. Cox regression was applied to the present hazard ratio (HR), associated 95% confidence intervals, and P values. Survival analyses were presented in a Kaplan-Meier plot.

RESULTS

The risk of PJI (HR 1.6 (0.5 to 4.9), P = .380), any revision (HR 0.8 (0.4 to 1.3), P = .295), and death (HR 1.3 (0.8 to 2.1), P = .282) was not increased in patients suffering from MetS compared with patients who did not have MetS. There was no PJI in patients not having MetS and receiving a knee arthroplasty. The risk of death was increased in the MetS group receiving a knee arthroplasty (HR 2.7 (1.3 to 5.9), P = .010), but not different from the MetS group receiving a hip arthroplasty. There was no elevated risk of PJI when analyzing morbid obesity (body mass index over 40), men, or diabetes as the exposures.

CONCLUSIONS

Patients suffering from MetS do not have an increased risk of revision caused by PJI. In general, performing hip and knee arthroplasty in patients suffering from MetS is without increased risk of revision surgery.

Course-based intra-articular injection of medical chitosan mitigates excessive deposition of triacylglycerides in the synovial tissue of the knee osteoarthritis

BACKGROUND

This study aimed to investigate the clinical efficacy of intra-articular injections of medical chitosan for treating knee osteoarthritis (KOA) and measure the lipid metabolism profiles of the synovial tissue.

METHODS

Sixty patients with KOA undergoing conservative treatment were recruited and randomized into two groups: one without pharmacological intervention (OA group) and the other receiving course-based intra-articular medical chitosan injections (CSI group). Quantitative lipidomic profile of synovial tissue was analyzed. Functional scores, including Kellgren-Lawrence rating (K-L), Visual Analog Scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scoring, and American Knee Society (AKS) scoring were conducted.

RESULTS

Survival from the initial conservative treatment to final knee arthroplasty was significantly longer in the CSI group compared to the OA group. Except for the presurgery VAS score, no statistically significant differences were observed in the other scores, including K-L, initial VAS, WOMAC, and AKS. However, the CSI group experienced more reductions in AKS-Knee subscores compared to the OA group. Compared to the CSI group, the OA group exhibited a significant upregulation in most differential lipids, particularly triacylglycerides (TAGs, 77%). The OA group had notably higher levels of long-chain unsaturated fatty acids.

CONCLUSION

Intra-articular injection of medical chitosan significantly prolongs the survival period before knee arthroplasty and reduces the deposition of TAGs metabolites.

The role of obesity and adipose tissue dysfunction in osteoarthritis pain

Obesity has a pivotal and multifaceted role in pain associated with osteoarthritis (OA), extending beyond the mechanistic influence of BMI. It exerts its effects both directly and indirectly through various modifiable risk factors associated with OA-related pain. Adipose tissue dysfunction is highly involved in OA-related pain through local and systemic inflammation, immune dysfunction, and the production of pro-inflammatory cytokines and adipokines. Adipose tissue dysfunction is intricately connected with metabolic syndrome, which independently exerts specific effects on OA-related pain, distinct from its association with BMI. The interplay among obesity, adipose tissue dysfunction and metabolic syndrome influences OA-related pain through diverse pain mechanisms, including nociceptive pain, peripheral sensitization and central sensitization. These complex interactions contribute to the heightened pain experience observed in individuals with OA and obesity. In addition, pain management strategies are less efficient in individuals with obesity. Importantly, therapeutic interventions targeting obesity and metabolic syndrome hold promise in managing OA-related pain. A deeper understanding of the intricate relationship between obesity, metabolic syndrome and OA-related pain is crucial and could have important implications for improving pain management and developing innovative therapeutic options in OA.

Unveiling the bioinformatic genes and their involved regulatory mechanisms in type 2 diabetes combined with osteoarthritis

Background

Type 2 Diabetes Mellitus (T2D) and Osteoarthritis (OA) are both prevalent diseases that significantly impact the health of patients. Increasing evidence suggests that there is a big correlation between T2D and OA, but the molecular mechanisms remain elusive. The aims of this study are to investigate the shared biomarkers and potential molecular mechanisms in T2D combined with OA.

Methods

T2D and OA-related differentially expressed genes (DEGs) were identified via bioinformatic analysis on Gene Expression Omnibus (GEO) datasets GSE26168 and GSE114007 respectively. Subsequently, extensive target prediction and network analysis were finished with Gene Ontology (GO), protein-protein interaction (PPI), and pathway enrichment with DEGs. The transcription factors (TFs) and miRNAs coupled in co-expressed DEGs involved in T2D and OA were predicted as well. The key genes expressed both in the clinical tissues of T2D and OA were detected with western blot and qRT-PCR assay. Finally, the most promising candidate compounds were predicted with the Drug-Gene Interaction Database (DGIdb) and molecular docking.

Results

In this study, 209 shared DEGs between T2D and OA were identified. Functional analysis disclosed that these DEGs are predominantly related to ossification, regulation of leukocyte migration, extracellular matrix (ECM) structural constituents, PI3K/AKT, and Wnt signaling pathways. Further analysis via Protein-Protein Interaction (PPI) analysis and validation with external datasets emphasized MMP9 and ANGPTL4 as crucial genes in both T2D and OA. Our findings were validated through qRT-PCR and Western blot analyses, which indicated high expression levels of these pivotal genes in T2D, OA, and T2D combined with OA cases. Additionally, the analysis of Transcription Factors (TFs)-miRNA interactions identified 7 TFs and one miRNA that jointly regulate these important genes. The Receiver Operating characteristic (ROC) analysis demonstrated the significant diagnostic potential of MMP9 and ANGPTL4.Moreover, we identified raloxifene, ezetimibe, and S-3304 as promising agents for patients with both T2D and OA.

Conclusion

This study uncovers the shared signaling pathways, biomarkers, potential therapeutics, and diagnostic models for individuals suffering from both T2D and OA. These findings not only present novel perspectives on the complex interplay between T2D and OA but also hold significant promise for improving the clinical management and prognosis of patients with this concurrent condition.

Metformin as adjuvant therapy in obese knee osteoarthritis patients

AIMS

This study aimed at investigating the efficacy of metformin as adjuvant therapy for obese knee osteoarthritis (OA) patients, considering its anti-inflammatory and cartilage-protective effects.

PATIENTS AND METHODS

In this randomized, double-blind, placebo-controlled study, 50 obese knee OA patients were assigned randomly to two groups, the metformin group (n = 25) which was treated with metformin 500 mg orally BID plus celecoxib 200 mg orally once daily, and the placebo group (n = 25) which was treated with placebo tablets BID plus celecoxib 200 mg orally once daily for 12 weeks. Cartilage Oligomeric Matrix Protein (COMP), C-terminal cross-linked telopeptide of type I collagen (CTX-1), and Interleukin 1-beta (IL-1β) serum levels were measured, while Western Ontario and McMaster Universities Arthritis Index (WOMAC) score assessed knee pain, stiffness, and physical function at baseline and after 12 weeks.

RESULTS

Following a 12-week treatment, the metformin group exhibited significantly reduced levels of COMP, CTX-1, and IL-1β in the serum compared to the placebo group (p = 0.0081, p = 0.0106, and p = 0.0223, respectively). Furthermore, metformin group produced significant improvements in WOMAC total scale (p < 0.0001), specifically in knee pain, stiffness, and physical function compared to placebo group (p < 0.0001, p < 0.0001, and p < 0.0001, respectively).

CONCLUSION

Metformin as an adjuvant therapy in obese knee OA patients may have beneficial effects on cartilage degradation and inflammation, as evidenced by the significant decreases in serum COMP, CTX-1, and IL-1β levels. Additionally, metformin may improve clinical outcomes, as shown by the significant improvements in WOMAC scores.

CLINICALTRIALS

GOV ID

NCT05638893/Registered December 6, 2022 - Retrospectively.

Diabetes and Osteoarthritis: Exploring the Interactions and Therapeutic Implications of Insulin, Metformin, and GLP-1-Based Interventions

Diabetes mellitus (DM) and osteoarthritis (OA) are prevalent chronic conditions with shared pathophysiological links, including inflammation and metabolic dysregulation. This study investigates the potential impact of insulin, metformin, and GLP-1-based therapies on OA progression. Methods involved a literature review of clinical trials and mechanistic studies exploring the effects of these medications on OA outcomes. Results indicate that insulin, beyond its role in glycemic control, may modulate inflammatory pathways relevant to OA, potentially influencing joint health. Metformin, recognized for its anti-inflammatory properties via AMPK activation, shows promise in mitigating OA progression by preserving cartilage integrity and reducing inflammatory markers. GLP-1-based therapies, known for enhancing insulin secretion and improving metabolic profiles in DM, also exhibit anti-inflammatory effects that may benefit OA by suppressing cytokine-mediated joint inflammation and supporting cartilage repair mechanisms. Conclusions suggest that these medications, while primarily indicated for diabetes management, hold therapeutic potential in OA by targeting common underlying mechanisms. Further clinical trials are warranted to validate these findings and explore optimal therapeutic strategies for managing both DM and OA comorbidities effectively.

S-Equol Ameliorates Menopausal Osteoarthritis in Rats through Reducing Oxidative Stress and Cartilage Degradation

Osteoarthritis (OA) is a chronic degenerative disease leading to articular cartilage destruction. Menopausal and postmenopausal women are susceptible to both OA and osteoporosis. S-equol, a soy isoflavone-derived molecule, is known to reduce osteoporosis in estrogen-deficient mice, but its role in OA remains unknown. This study aimed to explore the effect of S-equol on different degrees of menopausal OA in female Sprague-Dawley (SD) rats induced by estrogen deficiency caused by bilateral ovariectomy (OVX) combined with intra-articular injection of mono-iodoacetate (MIA). Knee joint histopathological change; serum biomarkers of bone turnover, including N-terminal propeptide of type I procollagen (PINP), C-terminal telopeptide of type I collagen (CTX-I) and N-terminal telopeptide of type I collagen (NTX-I); the cartilage degradation biomarkers hyaluronic acid (HA) and N-terminal propeptide of type II procollagen (PIINP); and the matrix-degrading enzymes matrix metalloproteinases (MMP)-1, MMP-3 and MMP-13, as well as the oxidative stress-inducing molecules nitric oxide (NO) and hydrogen peroxide (H2O2), were assessed for evaluation of OA progression after S-equol supplementation for 8 weeks. The results showed that OVX without or with MIA injection induced various severity levels of menopausal OA by increasing pathological damage, oxidative stress, and cartilage matrix degradation to various degrees. Moreover, S-equol supplementation could significantly reduce these increased biomarkers in different severity levels of OA. This indicates that S-equol can lessen menopausal OA progression by reducing oxidative stress and the matrix-degrading enzymes involved in cartilage degradation.

Association between hepatic steatosis and fibrosis and arthritis among US adults: A population-based study

BACKGROUND

Lipid metabolism factors may play a role in the development of arthritis and hepatic steatosis and fibrosis. The aim of this study was to explore the potential association between arthritis and hepatic steatosis and liver fibrosis.

MATERIALS AND METHODS

The nationally representative sample from the National Health and Nutrition Examination Survey was analyzed, with data on arthritis diagnosis, subtype, and liver status obtained. Liver status was assessed using transient elastography. Hepatic steatosis was defined as a Controlled Attenuation Parameter (CAP) score ≥263 dB/m, and liver fibrosis status was defined as F0‒F4. Logistic regression models and subgroup analyses stratified by sex were used to evaluate the associations. Smooth curve fitting was used to describe the associations.

RESULTS

The present study of 6,840 adults aged 20 years or older found a significant positive correlation between arthritis and CAP in multivariate logistic regression analysis (β = 0.003, 95 % CI 0.001 to 0.0041, p < 0.001). Participants with arthritis had a higher risk of hepatic steatosis (OR = 1.248, 95 % CI 1.036 to 1.504, p = 0.020), particularly those with osteoarthritis or degenerative arthritis, but not rheumatoid arthritis (p = 0.847). The positive correlation was maintained in females (β = 0.004, 95 % CI 0.002 to 0.006, p < 0.001), but not in males. There was no significant relationship between arthritis and liver fibrosis (p = 0.508).

CONCLUSION

This study indicates that there is a positive correlation between arthritis and hepatic steatosis, particularly in females. Nonetheless, there is no significant relationship between arthritis and the risk of liver fibrosis.

Autophagy in Osteoarthritis: A Double-Edged Sword in Cartilage Aging and Mechanical Stress Response: A Systematic Review

Background: Although osteoarthritis (OA) development is epidemiologically multifactorial, a primary underlying mechanism is still under debate. Understanding the pathophysiology of OA remains challenging. Recently, experts have focused on autophagy as a contributor to OA development. Method: To better understand the pathogenesis of OA, we survey the literature on the role of autophagy and the molecular mechanisms of OA development. To identify relevant studies, we used controlled vocabulary and free text keywords to search the MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Web of Science, and SCOPUS database. Thirty-one studies were included for data extraction and systematic review. Among these studies, twenty-five studies investigated the effects of autophagy in aging and OA chondrocytes, six studies examined the effects of autophagy in normal human chondrocytes, and only one study investigated the effects of mechanical stress-induced autophagy on the development of OA in normal chondrocytes. Results: The studies suggest that autophagy activation prevents OA by exerting cell-protective effects in normal human chondrocytes. However, in aging and osteoarthritis (OA) chondrocytes, the role of autophagy is intricate, as certain studies indicate that stimulating autophagy in these cells can have a cytotoxic effect, while others propose that it may have a protective (cytoprotective) effect against damage or degeneration. Conclusions: Mechanical stress-induced autophagy is also thought to be involved in the development of OA, but further research is required to identify the precise mechanism. Thus, autophagy contributions should be interpreted with caution in aging and the types of OA cartilage.

Early Outcomes of Orthopedic Pre-surgical Patients Enrolled in an Intensive, Interprofessional Lifestyle Medicine Program to Optimize Health

Recently, lifestyle medicine (LSM) application has shown feasibility for musculoskeletal pain patients with co-existing lifestyle-related chronic diseases. This study describes early results of a LSM program for musculoskeletal patients with goals to optimize health prior to orthopedic surgery. Fifty-four patients (age: 61 ± 11 years; 39 [72%] females) completed the program from 3/8/22-12/1/23. Data included patient goals, utilization, goal attainment, and patient outcomes. Most patients (41/54 [76%]) enrolled with established surgical dates. Mean BMI was 43.2 ± 5.3 kg/m2, and 89% had ≥2 lifestyle-related chronic diseases. The majority reported impaired sleep (79%) and zero cumulative minutes of physical activity/week (57%). Mean program duration was 13 ± 8 weeks involving 5 ± 4 visits with members of the interprofessional team. Fifty-two (96%) patients successfully attained pre-program goals, and 49/54 (91%) met their surgical goal. Of the patients enrolled without surgical dates, 11/13 (85%) optimized their health and proceeded to surgery. Forty-two (78%) patients reported decreases in weight and BMI, averaging 11 ± 7 lbs and 1.8 ± 1.3 kg/m2, respectively. Rates of improvement in pain, PROMIS-10 physical and mental health, and PHQ-4 were 52%, 37%, 45%, and 47%, respectively. These data demonstrate the feasibility and effectiveness of a LSM program to address whole-person health optimization and enable orthopedic patients to improve lifestyle behaviors and proceed to orthopedic surgery.

Associations of inflammatory and metabolic biomarkers with incident erosive hand osteoarthritis in the osteoarthritis initiative cohort

OBJECTIVE

Erosive hand osteoarthritis (eHOA) is a subtype of hand osteoarthritis (OA) that develops in finger joints with pre-existing OA and is differentiated by clinical characteristics (hand pain/disability, inflammation, and erosions) that suggest inflammatory or metabolic processes.

METHOD

This was a longitudinal nested case-cohort design among Osteoarthritis Initiative participants who had hand radiographs at baseline and 48-months, and biospecimens collected at baseline. We classified incident radiographic eHOA in individuals with ≥1 joint with Kellgren-Lawrence ≥2 and a central erosion present at 48-months but not at baseline. We used a random representative sample (n = 1282) for comparison. We measured serum biomarkers of inflammation, insulin resistance and dysglycemia, and adipokines using immunoassays and enzymatic colorimetric procedures, blinded to case status.

RESULTS

Eighty-six participants developed incident radiographic eHOA. In the multivariate analyses adjusted for age, gender, race, smoking, and body mass index, and after adjustment for multiple analyses, incident radiographic eHOA was associated with elevated levels of interleukin-7 (risk ratio (RR) per SD = 1.30 [95% confidence interval (CI) 1.09, 1.55] p trend 0.01).

CONCLUSION

This exploratory study suggests an association of elevated interleukin-7, an inflammatory cytokine, with incident eHOA, while other cytokines or biomarkers of metabolic inflammation were not associated. Interleukin-7 may mediate inflammation and tissue damage in susceptible osteoarthritic finger joints and participate in erosive progression.

Exploration beyond osteoarthritis: the association and mechanism of its related comorbidities

Osteoarthritis is the most prevalent age-related degenerative joint disease and a leading cause of pain and disability in aged people. Its etiology is multifaceted, involving factors such as biomechanics, pro-inflammatory mediators, genetics, and metabolism. Beyond its evident impact on joint functionality and the erosion of patients' quality of life, OA exhibits symbiotic relationships with various systemic diseases, giving rise to various complications. This review reveals OA's extensive impact, encompassing osteoporosis, sarcopenia, cardiovascular diseases, diabetes mellitus, neurological disorders, mental health, and even cancer. Shared inflammatory processes, genetic factors, and lifestyle elements link OA to these systemic conditions. Consequently, recognizing these connections and addressing them offers opportunities to enhance patient care and reduce the burden of associated diseases, emphasizing the need for a holistic approach to managing OA and its complications.

The Metabolic Syndrome, a Human Disease

This review focuses on the question of metabolic syndrome (MS) being a complex, but essentially monophyletic, galaxy of associated diseases/disorders, or just a syndrome of related but rather independent pathologies. The human nature of MS (its exceptionality in Nature and its close interdependence with human action and evolution) is presented and discussed. The text also describes the close interdependence of its components, with special emphasis on the description of their interrelations (including their syndromic development and recruitment), as well as their consequences upon energy handling and partition. The main theories on MS's origin and development are presented in relation to hepatic steatosis, type 2 diabetes, and obesity, but encompass most of the MS components described so far. The differential effects of sex and its biological consequences are considered under the light of human social needs and evolution, which are also directly related to MS epidemiology, severity, and relations with senescence. The triggering and maintenance factors of MS are discussed, with especial emphasis on inflammation, a complex process affecting different levels of organization and which is a critical element for MS development. Inflammation is also related to the operation of connective tissue (including the adipose organ) and the widely studied and acknowledged influence of diet. The role of diet composition, including the transcendence of the anaplerotic maintenance of the Krebs cycle from dietary amino acid supply (and its timing), is developed in the context of testosterone and β-estradiol control of the insulin-glycaemia hepatic core system of carbohydrate-triacylglycerol energy handling. The high probability of MS acting as a unique complex biological control system (essentially monophyletic) is presented, together with additional perspectives/considerations on the treatment of this 'very' human disease.

Beneficial Impact of Eicosapentaenoic Acid on the Adverse Effects Induced by Palmitate and Hyperglycemia on Healthy Rat Chondrocyte

Osteoarthritis (OA) is the most prevalent form of arthritis and a major cause of pain and disability. The pathology of OA involves the whole joint in an inflammatory and degenerative process, especially in articular cartilage. OA may be divided into distinguishable phenotypes including one associated with the metabolic syndrome (MetS) of which dyslipidemia and hyperglycemia have been individually linked to OA. Since their combined role in OA pathogenesis remains to be elucidated, we investigated the chondrocyte response to these metabolic stresses, and determined whether a n-3 polyunsaturated fatty acid (PUFA), i.e., eicosapentaenoic acid (EPA), may preserve chondrocyte functions. Rat chondrocytes were cultured with palmitic acid (PA) and/or EPA in normal or high glucose conditions. The expression of genes encoding proteins found in cartilage matrix (type 2 collagen and aggrecan) or involved in degenerative (metalloproteinases, MMPs) or in inflammatory (cyclooxygenase-2, COX-2 and microsomal prostaglandin E synthase, mPGES) processes was analyzed by qPCR. Prostaglandin E2 (PGE2) release was also evaluated by an enzyme-linked immunosorbent assay. Our data indicated that PA dose-dependently up-regulated the mRNA expression of MMP-3 and -13. PA also induced the expression of COX-2 and mPGES and promoted the synthesis of PGE2. Glucose at high concentrations further increased the chondrocyte response to PA. Interestingly, EPA suppressed the inflammatory effects of PA and glucose, and strongly reduced MMP-13 expression. Among the free fatty acid receptors (FFARs), FFAR4 partly mediated the EPA effects and the activation of FFAR1 markedly reduced the inflammatory effects of PA in high glucose conditions. Our findings demonstrate that dyslipidemia associated with hyperglycemia may contribute to OA pathogenesis and explains why an excess of saturated fatty acids and a low level in n-3 PUFAs may disrupt cartilage homeostasis.

Metabolic syndrome increases osteoarthritis risk: findings from the UK Biobank prospective cohort study

OBJECTIVE

The association between Metabolic Syndrome (MetS), its components, and the risk of osteoarthritis (OA) has been a topic of conflicting evidence in different studies. The aim of this present study is to investigate the association between MetS, its components, and the risk of OA using data from the UK Biobank.

METHODS

A prospective cohort study was conducted in the UK Biobank to assess the risk of osteoarthritis (OA) related to MetS. MetS was defined according to the criteria set by the International Diabetes Federation (IDF). Additionally, lifestyle factors, medications, and the inflammatory marker C-reactive protein (CRP) were included in the model. Cox proportional hazards regression was used to calculate hazard ratios (HR) and 95% confidence intervals (CI). The cumulative risk of OA was analyzed using Kaplan-Meier curves and log-rank tests. To explore potential nonlinear associations between MetS components and OA risk, a restricted cubic splines (RCS) model was employed. In addition, the polygenic risk score (PRS) of OA was calculated to characterize individual genetic risk.

RESULTS

A total of 45,581 cases of OA were identified among 370,311 participants, with a median follow-up time of 12.48 years. The study found that individuals with MetS had a 15% higher risk of developing OA (HR = 1.15, 95%CI:1.12-1.19). Additionally, central obesity was associated with a 58% increased risk of OA (HR = 1.58, 95%CI:1.5-1.66), while hyperglycemia was linked to a 13% higher risk (HR = 1.13, 95%CI:1.1-1.15). Dyslipidemia, specifically in triglycerides (HR = 1.07, 95%CI:1.05-1.09) and high-density lipoprotein (HR = 1.05, 95%CI:1.02-1.07), was also found to be slightly associated with OA risk. When stratified by PRS, those in the high PRS group had a significantly higher risk of OA compared to those with a low PRS, whereas no interaction was found between MetS and PRS on OA risks. Furthermore, the presence of MetS significantly increased the risk of OA by up to 35% in individuals with elevated CRP levels (HR = 1.35, 95% CI:1.3-1.4).

CONCLUSION

MetS and its components have been found to be associated with an increased risk of OA, particularly in individuals with elevated levels of CRP. These findings highlight the significance of managing MetS as a preventive and intervention measure for OA.

The association between lipid biomarkers and osteoarthritis based on the National Health and Nutrition Examination Survey and Mendelian randomization study

To explore the association between lipid markers and osteoarthritis (OA). First, the National Health and Nutrition Examination Survey (NHANES) database was used to screen participants with lipid markers, OA and relevant covariates, and logistic regression was used to analyze the association between lipid markers and OA; Then, under the theoretical framework of Mendelian randomization (MR), two-sample MR was performed using GWAS data of lipid markers and OA to explore the causal association between the two, which was analyzed by inverse variance weighting (IVW) method. Heterogeneity test, sensitivity analysis and pleiotropy analysis were also performed. The NHANES database screened a total of 3706 participants, of whom 836 had OA and 2870 did not have OA. When lipid markers were used as continuous variables, multivariate logistic results showed an association between HDL, LDL and OA (HDL, OR (95%):1.01 (1.00, 1.01); LDL, OR (95%):1.00 (0.99, 1.00)). When lipid markers were used as categorical variables, multivariate logistic results showed the fourth quartile result of 0.713 (0.513, 0.992) for LDL relative to the first quartile. In MR study, the results of the IVW method for TG, TL, HDL and LDL showed OR (95% CI) of 1.06 (0.97-1.16), 0.95 (0.85-1.06), 0.94 (0.86-1.02) and 0.89 (0.80-0.998) with P-values of 0.21, 0.37. 013, 0.046. The heterogeneity tests and multiplicity analyses showed P-values greater than 0.05, and sensitivity analyses showed no abnormal single nucleotide polymorphisms. Through NHANES database and MR analyses, LDL was found to be a protective factor for OA, while HDL still needs further study. Our results provide new biomarkers for preventive and therapeutic strategies for OA.

Metformin for knee osteoarthritis with obesity: study protocol for a randomised, double-blind, placebo-controlled trial

INTRODUCTION

Over half of the populations with knee osteoarthritis (OA) have obesity. These individuals have many other shared metabolic risk factors. Metformin is a safe, inexpensive, well-tolerated drug that has pleiotropic effects, including structural protection, anti-inflammatory and analgesic effects in OA, specifically the knee. The aim of this randomised, double-blind, placebo-controlled trial is to determine whether metformin reduces knee pain over 6 months in individuals with symptomatic knee OA who are overweight or obese.

METHODS AND ANALYSIS

One hundred and two participants with symptomatic knee OA and overweight or obesity will be recruited from the community in Melbourne, Australia, and randomly allocated in a 1:1 ratio to receive either metformin 2 g or identical placebo daily for 6 months. The primary outcome is reduction of knee pain [assessed by 100 mm Visual Analogue Scale (VAS)] at 6 months. The secondary outcomes are OMERACT-OARSI (Outcome Measures in Rheumatology-Osteoarthritis Research Society International) responder criteria [Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, function and participant's global assessment (VAS)] at 6 months; change in knee pain, stiffness, function using WOMAC at 6 months and quality of life at 6 months. Adverse events will be recorded. The primary analysis will be by intention to treat, including all participants in their randomised groups.

ETHICS AND DISSEMINATION

Ethics approval has been obtained from the Alfred Hospital Ethics Committee (708/20) and Monash University Human Research Ethics Committee (28498). Written informed consent will be obtained from all the participants. The findings will be disseminated through peer-review publications and conference presentations.

TRIAL REGISTRATION NUMBER

ACTRN12621000710820 .

Risk of metabolic abnormalities in osteoarthritis: a new perspective to understand its pathological mechanisms

Although aging has traditionally been viewed as the most important risk factor for osteoarthritis (OA), an increasing amount of epidemiological evidence has highlighted the association between metabolic abnormalities and OA, particularly in younger individuals. Metabolic abnormalities, such as obesity and type II diabetes, are strongly linked to OA, and they affect both weight-bearing and non-weight-bearing joints, thus suggesting that the pathogenesis of OA is more complicated than the mechanical stress induced by overweight. This review aims to explore the recent advances in research on the relationship between metabolic abnormalities and OA risk, including the impact of abnormal glucose and lipid metabolism, the potential pathogenesis and targeted therapeutic strategies.

Trajectory of metabolic syndrome and its association with knee pain in middle-aged adults

OBJECTIVE

Metabolic syndrome (MetS) is characterised by the clustering of central obesity with metabolic abnormalities. We aimed to describe the association of MetS and trajectories of MetS over 10-13 years with knee symptoms in general population-based middle-aged adults.

METHODS

Fasting blood biochemistry, waist circumference and blood pressure measures were collected during Childhood Determinants of Adult Health (CDAH)-1 study (year:2004-6; n = 2447; mean age:31.48 ± 2.60) and after 10-13 year at CDAH-3 (year:2014-2019; n = 1549; mean age:44 ± 2.90). Participants were defined as having MetS as per International Diabetes Federation (IDF) definition. Knee symptoms were assessed using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale at CDAH-3 (mid-adulthood).

RESULTS

The prevalence of MetS increased from 8 % at young adulthood (female:52.06 %) to 13 % in mid-adulthood (female:53.78 %) over 10-13 years. Presence of MetS at mid-adulthood was associated with knee symptoms at mid-adulthood [ratio of means (RoM): 1.33; 95%CI:1.27,1.39]. Four MetS trajectories were identified-'No MetS' (85.01 %); 'Improved MetS' (2.14 %), 'Incident MetS' (8.81 %), and 'Persistent MetS, (4.04 %). Compared to 'No MetS', 'Persistent MetS' [RoM:1.15; 95%CI:1.06,1.25], 'Incident MetS' [RoM:1.56; 95%CI:1.48,1.65], and 'Improved MetS' [RoM:1.22; 95%CI:1.05,1.41] was associated with higher knee symptoms. Notably, 'Incident MetS' was strongly associated with knee symptoms [RoM: 1.56; 95%CI:1.48,1.65] and pain [RoM:1.52; 95%CI:1.37,1.70] at mid-adulthood.

CONCLUSION

In this sample of middle-aged adults, there was a significant positive association between MetS and knee symptoms. Relative to those without MetS at either life stage, the elevation in mean knee pain scores was more pronounced for those who developed MetS after young adulthood than for those who had MetS in young adulthood.

Image-Guided Radiofrequency Ablation for Joint and Back Pain: Rationales, Techniques, and Results

Image-guided minimally invasive radiofrequency ablation (RFA) of sensory nerves has emerged as a treatment option for pain and swelling associated with advanced symptomatic joint and spine degeneration to bridge the gap between optimal medical therapy and surgical treatments. RFA of articular sensory nerves and the basivertebral nerve use image-guided percutaneous approaches resulting in faster recovery time and minimal risks. The current published evidence indicates clinical effectiveness; however, further research must be performed comparing other conservative treatments with RFA to understand further its role in different clinical settings, such as osteonecrosis. This review article discusses and illustrates the applications of RFA for treating symptomatic joint and spine degeneration.

A multidisciplinary lifestyle program for metabolic syndrome-associated osteoarthritis: the "Plants for Joints" randomized controlled trial

OBJECTIVE

To determine the effectiveness of the "Plants for Joints" multidisciplinary lifestyle program in patients with metabolic syndrome-associated osteoarthritis (MSOA).

DESIGN

Patients with hip or knee MSOA were randomized to the intervention or control group. The intervention group followed a 16-week program in addition to usual care based on a whole food plant-based diet, physical activity, and stress management. The control group received usual care. The patient-reported Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) total score (range 0-96) was the primary outcome. Secondary outcomes included other patient-reported, anthropometric, and metabolic measures. An intention-to-treat analysis with a linear-mixed model adjusted for baseline values was used to analyze between-group differences.

RESULTS

Of the 66 people randomized, 64 completed the study. Participants (84% female) had a mean (SD) age of 63 (6) years and body mass index of 33 (5) kg/m2. After 16 weeks, the intervention group (n = 32) had a mean 11-point larger improvement in WOMAC-score (95% CI 6-16; p = 0.0001) compared to the control group. The intervention group also lost more weight (-5 kg), fat mass (-4 kg), and waist circumference (-6 cm) compared to the control group. Patient-Reported Outcomes Measurement Information System (PROMIS) fatigue, pain interference, C-reactive protein, hemoglobin A1c, fasting glucose, and low-density lipoproteins improved in the intervention versus the control group, while other PROMIS measures, blood pressure, high-density lipoproteins, and triglycerides did not differ significantly between the groups.

CONCLUSION

The "Plants for Joints" lifestyle program reduced stiffness, relieved pain, and improved physical function in people with hip or knee MSOA compared to usual care.

Relationship of Chronic Systemic Inflammation to Both Chronic Lifestyle-Related Diseases and Osteoarthritis: The Case for Lifestyle Medicine for Osteoarthritis

Systemic inflammation is a root cause of lifestyle-related chronic diseases and may also play a role in the development and progression of osteoarthritis (OA). Lifestyle medicine seeks to treat, prevent, and reverse lifestyle-related chronic disease via 6 pillars: nutrition, sleep health, stress management, physical activity, social connections, and risky behavior avoidance/reduction. This article presents a review of the literature in which we assess the connections between the 6 pillars of lifestyle medicine, chronic systemic inflammation, and OA. We also discuss the whole-person approach that lifestyle medicine interventions can provide to reduce chronic systemic inflammation and affect the development or progression of OA.

Mechanisms of tissue degeneration mediated by periostin in spinal degenerative diseases and their implications for pathology and diagnosis: a review

Periostin (POSTN) serves a dual role as both a matricellular protein and an extracellular matrix (ECM) protein and is widely expressed in various tissues and cells. As an ECM protein, POSTN binds to integrin receptors, transduces signals to cells, enabling cell activation. POSTN has been linked with various diseases, including atopic dermatitis, asthma, and the progression of multiple cancers. Recently, its association with orthopedic diseases, such as osteoporosis, osteoarthritis resulting from cartilage destruction, degenerative diseases of the intervertebral disks, and ligament degenerative diseases, has also become apparent. Furthermore, POSTN has been shown to be a valuable biomarker for understanding the pathophysiology of orthopedic diseases. In addition to serum POSTN, synovial fluid POSTN in joints has been reported to be useful as a biomarker. Risk factors for spinal degenerative diseases include aging, mechanical stress, trauma, genetic predisposition, obesity, and metabolic syndrome, but the cause of spinal degenerative diseases (SDDs) remains unclear. Studies on the pathophysiological effects of POSTN may significantly contribute toward the diagnosis and treatment of spinal degenerative diseases. Therefore, in this review, we aim to examine the mechanisms of tissue degeneration caused by mechanical and inflammatory stresses in the bones, cartilage, intervertebral disks, and ligaments, which are crucial components of the spine, with a focus on POSTN.

Gut-spine axis: a possible correlation between gut microbiota and spinal degenerative diseases

As society ages, the number of patients with spinal degenerative diseases (SDD) is increasing, posing a major socioeconomic problem for patients and their families. SDD refers to a generic term for degenerative diseases of spinal structures, including osteoporosis (bone), facet osteoarthritis (joint), intervertebral disk degeneration (disk), lumbar spinal canal stenosis (yellow ligament), and spinal sarcopenia (muscle). We propose the term "gut-spine axis" for the first time, given the influence of gut microbiota (GM) on the metabolic, immune, and endocrine environment in hosts through various potential mechanisms. A close cross-talk is noted between the aforementioned spinal components and degenerative diseases. This review outlines the nature and role of GM, highlighting GM abnormalities associated with the degeneration of spinal components. It also summarizes the evidence linking GM to various SDD. The gut-spine axis perspective can provide novel insights into the pathogenesis and treatment of SDD.

Fundamentals of osteoarthritis: Inflammatory mediators in osteoarthritis

OBJECTIVES

As more has become known of the pathophysiology of osteoarthritis (OA), evidence that inflammation plays a critical role in its development and progression has accumulated. Here, we aim to review current knowledge of the complex inflammatory network in the OA joint.

DESIGN

This narrative review is presented in three main sections: local inflammation, systemic inflammation, and therapeutic implications. We focused on inflammatory mediators and their link to OA structural changes in the joint.

RESULTS

OA is characterized by chronic and low-grade inflammation mediated mostly by the innate immune system, which results in cartilage degradation, bone remodeling and synovial changes. Synovitis is regarded as an OA characteristic and associated with increased severity of symptoms and joint dysfunction. However, the articular cartilage and the subchondral bone also produce several pro-inflammatory mediators thus establishing a complex interplay between the different tissues of the joint. In addition, systemic low-grade inflammation induced by aging, obesity and metabolic syndrome can contribute to OA development and progression. The main inflammatory mediators associated with OA include cytokines, chemokines, growth factors, adipokines, and neuropeptides.

CONCLUSIONS

Future research is needed to deeper understand the molecular pathways mediating the inflammation in OA to provide new therapeutics that target these pathways, or to repurpose existing drugs.

Changes in the Subchondral Bone, Visfatin, and Cartilage Biomarkers after Pharmacological Treatment of Experimental Osteoarthritis with Metformin and Alendronate

Subchondral bone that has intense communication with the articular cartilage might be a potential target for pharmacological treatment in the early stages of osteoarthritis (OA). Considering the emerging data about the role of adipokines in the pathogenesis of OA, the administration of drugs that influence their level is also intriguing. Metformin and alendronate were administered in mice with collagenase-induced OA (CIOA) as a monotherapy and in combination. Safranin O staining was used for the assessment of changes in subchondral bone and articular cartilage. Before and after treatment, serum levels of visfatin and biomarkers of cartilage turnover (CTX-II, MMP-13, and COMP) were assessed. In the current study, the combined administration of alendronate and metformin in mice with CIOA led to the protection against cartilage and subchondral bone damage. In mice with CIOA, metformin led to a decrease in visfatin level. In addition, treatment with metformin, alendronate, or their combination lowered the level of cartilage biomarkers (CTX-II and COMP), while the level of MMP-13 was not influenced. In conclusion, personalized combination treatment in OA according to clinical phenotype, especially in the early stages of the disease, might lead to the identification of a successful disease-modifying therapeutic protocol in OA.

Culture-expanded mesenchymal stromal cell therapy: does it work in knee osteoarthritis? A pathway to clinical success

Osteoarthritis (OA) is a degenerative multifactorial disease with concomitant structural, inflammatory, and metabolic changes that fluctuate in a temporal and patient-specific manner. This complexity has contributed to refractory responses to various treatments. MSCs have shown promise as multimodal therapeutics in mitigating OA symptoms and disease progression. Here, we evaluated 15 randomized controlled clinical trials (RCTs) and 11 nonrandomized RCTs using culture-expanded MSCs in the treatment of knee OA, and we found net positive effects of MSCs on mitigating pain and symptoms (improving function in 12/15 RCTs relative to baseline and in 11/15 RCTs relative to control groups at study endpoints) and on cartilage protection and/or repair (18/21 clinical studies). We examined MSC dose, tissue of origin, and autologous vs. allogeneic origins as well as patient clinical phenotype, endotype, age, sex and level of OA severity as key parameters in parsing MSC clinical effectiveness. The relatively small sample size of 610 patients limited the drawing of definitive conclusions. Nonetheless, we noted trends toward moderate to higher doses of MSCs in select OA patient clinical phenotypes mitigating pain and leading to structural improvements or cartilage preservation. Evidence from preclinical studies is supportive of MSC anti-inflammatory and immunomodulatory effects, but additional investigations on immunomodulatory, chondroprotective and other clinical mechanisms of action are needed. We hypothesize that MSC basal immunomodulatory "fitness" correlates with OA treatment efficacy, but this hypothesis needs to be validated in future studies. We conclude with a roadmap articulating the need to match an OA patient subset defined by molecular endotype and clinical phenotype with basally immunomodulatory "fit" or engineered-to-be-fit-for-OA MSCs in well-designed, data-intensive clinical trials to advance the field.

Acute and adaptive cardiovascular and metabolic effects of passive heat therapy or high-intensity interval training in patients with severe lower-limb osteoarthritis

Exercise is painful and difficult to perform for patients with severe lower-limb osteoarthritis; consequently, reduced physical activity contributes to increased cardiometabolic disease risk. The aim of this study was to characterize the acute and adaptive cardiovascular and metabolic effects of two low or no impact therapies in patients with severe lower-limb osteoarthritis: passive heat therapy (Heat) and high-intensity interval training (HIIT) utilizing primarily the unaffected limbs, compared to a control intervention of home-based exercise (Home). Participants completed up to 12 weeks of either Heat (20-30 min immersed in 40°C water followed by ~15-min light resistance exercise), HIIT (6-8 × 60-s intervals on a cross-trainer or arm ergometer at ~90-100% peakV ̇ $$ \dot{V} $$ O2 ) or Home (~15-min light resistance exercise); all 3 sessions/week. Reductions in systolic (12 & 10 mm Hg), diastolic (7 & 4 mm Hg), and mean arterial (8 & 6 mm Hg) blood pressure (BP) were observed following one bout of Heat or HIIT exposure, lasting for the duration of the 20-min monitoring period. Across the interventions (i.e., 12 weeks), resting systolic BP and diastolic BP decreased with Heat (-9 & -4 mm Hg; p < 0.001) and HIIT (-7 & -3 mm Hg; p ≤ 0.011), but not Home (0 & 0 mm Hg; p ≥ 0.785). The systolic and diastolic BP responses to an acute exposure of Heat or HIIT in the first intervention session were moderately correlated with adaptive responses across the intervention (r ≥ 0.54, p ≤ 0.005). Neither intervention improved indices of glycemic control (p = 0.310). In summary, both Heat and HIIT induced potent immediate and adaptive hypotensive effects, and the acute response was moderately predictive of the long-term response.

Demographic and radiographic factors for knee symptoms and range of motion in patients with knee osteoarthritis: a cross-sectional study in Beijing, China

BACKGROUND

Knee osteoarthritis (KOA) causes not only pain, stiffness, and dysfunction of the knee, but also the reduction of the joint range of motion (ROM). This study explored the demographic and radiographic factors for knee symptoms and ROM in patients with symptomatic KOA.

METHODS

The demographic variables, Kellgren-Lawrence (KL) grade, and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) of patients with symptomatic KOA recruited in Beijing were collected. The knee ROM of all patients were also measured. We analyzed the influencing factors for WOMAC and ROM using a generalize linear model, respectively.

RESULTS

This study included a total of 2034 patients with symptomatic KOA, including 530 males (26.1%) and 1504 females (73.0%), with a mean age of 59.17 (± 10.22) years. Patients with advanced age, overweight or obesity, a family history of KOA, a moderate-to-heavy manual labor job and use of nonsteroidal anti-inflammatory drugs (NSAIDs) had significantly higher WOMAC and lower ROM (all P < 0.05). The more the comorbidities, the higher the WOMAC (all P < 0.05). Patients with higher education had better ROM than those with only an elementary education(β = 4.905, P < 0.05). Compared with those KL = 0/1, the WOMAC of patients whose KL = 4 were higher (β = 0.069, P < 0.05), but the WOMAC of those KL = 2 were lower (β = -0.068, P < 0.05). ROM decreased with the increase of KL grade (all P < 0.05).

CONCLUSIONS

KOA patients with advanced age, overweight or obesity, a family history of KOA in first-degree relatives, a moderate-to-heavy manual labor job tended to have more severe clinical symptoms and worse ROM. Patients with more severe imaging lesions tend to have poorer ROM. Symptom management measures and regular ROM screening should be taken early to these people.

Osteoarthritis and Diabetes: Where Are We and Where Should We Go?

Diabetes mellitus (DM) and osteoarthritis (OA) are chronic noncommunicable diseases that affect millions of people worldwide. OA and DM are prevalent worldwide and associated with chronic pain and disability. Evidence suggests that DM and OA coexist within the same population. The coexistence of DM in patients with OA has been linked to the development and progression of the disease. Furthermore, DM is associated with a greater degree of osteoarthritic pain. Numerous risk factors are common to both DM and OA. Age, sex, race, and metabolic diseases (e.g., obesity, hypertension, and dyslipidemia) have been identified as risk factors. These risk factors (demographics and metabolic disorder) are associated with DM or OA. Other possible factors may include sleep disorders and depression. Medications for metabolic syndromes might be related to the incidence and progression of OA, with conflicting results. Given the growing body of evidence indicating a relationship between DM and OA, it is vital to analyze, interpret, and integrate these findings. Therefore, the purpose of this review was to evaluate the evidence on the prevalence, relationship, pain, and risk factors of both DM and OA. The research was limited to knee, hip, and hand OA.

Macrophage-Driven Inflammation in Metabolic Osteoarthritis: Implications for Biomarker and Therapy Development

Osteoarthritis (OA) is a common and debilitating joint disorder that leads to progressive joint breakdown and loss of articular cartilage. Accompanied by a state of low-grade inflammation, its etiology extends beyond that of a wear-and-tear disease, and the immune system might have a role in its initiation and progression. Obesity, which is directly associated with an increased incidence of OA, alters adipokine release, increases pro-inflammatory macrophage activity, and affects joint immune regulation. Studying inflammatory macrophage expression and strategies to inhibit inflammatory macrophage phenotype polarization might provide insights into disease pathogenesis and therapeutic applications. In pre-clinical studies, the detection of OA in its initial stages was shown to be possible using imaging techniques such as SPECT-CT, and advances are made to detect OA through blood-based biomarker analysis. In this review, obesity-induced osteoarthritis and its mechanisms in inducing joint degeneration are summarized, along with an analysis of the current developments in patient imaging and biomarker use for diagnostic and therapeutic strategies.

Intensive cholesterol-lowering treatment reduces synovial inflammation during early collagenase-induced osteoarthritis, but not pathology at end-stage disease in female dyslipidemic E3L.CETP mice

INTRODUCTION

The association between metabolic syndrome (MetS) and osteoarthritis (OA) development has become increasingly recognized. In this context, the exact role of cholesterol and cholesterol-lowering therapies in OA development has remained elusive. Recently, we did not observe beneficial effects of intensive cholesterol-lowering treatments on spontaneous OA development in E3L.CETP mice. We postulated that in the presence of local inflammation caused by a joint lesion, cholesterol-lowering therapies may ameliorate OA pathology.

MATERIALS AND METHODS

Female ApoE3∗Leiden.CETP mice were fed a cholesterol-supplemented Western type diet. After 3 weeks, half of the mice received intensive cholesterol-lowering treatment consisting of atorvastatin and the anti-PCSK9 antibody alirocumab. Three weeks after the start of the treatment, OA was induced via intra-articular injections of collagenase. Serum levels of cholesterol and triglycerides were monitored throughout the study. Knee joints were analyzed for synovial inflammation, cartilage degeneration, subchondral bone sclerosis and ectopic bone formation using histology. Inflammatory cytokines were determined in serum and synovial washouts.

RESULTS

Cholesterol-lowering treatment strongly reduced serum cholesterol and triglyceride levels. Mice receiving cholesterol-lowering treatment showed a significant reduction in synovial inflammation (P = 0.008, WTD: 95% CI: 1.4- 2.3; WTD + AA: 95% CI: 0.8- 1.5) and synovial lining thickness (WTD: 95% CI: 3.0-4.6, WTD + AA: 95% CI: 2.1-3.2) during early-stage collagenase-induced OA. Serum levels of S100A8/A9, MCP-1 and KC were significantly reduced after cholesterol-lowering treatment (P = 0.0005, 95% CI: -46.0 to -12.0; P = 2.8 × 10^-10, 95% CI: -398.3 to -152.1; P = 2.1 × 10^-9, -66.8 to -30.4, respectively). However, this reduction did not reduce OA pathology, determined by ectopic bone formation, subchondral bone sclerosis and cartilage damage at end-stage disease.

CONCLUSION

This study shows that intensive cholesterol-lowering treatment reduces joint inflammation after induction of collagenase-induced OA, but this did not reduce end stage pathology in female mice.

Biomarkers of Osteoarthritis—A Narrative Review on Causal Links with Metabolic Syndrome

Development of OA (OA) is multifactorial and is strongly associated with risk factors such as aging, trauma, metabolic disorders, and obesity. Metabolic Syndrome (MetS)-associated OA, collectively coined MetS-OA, is an increasingly recognized entity in which metabolic disorders and low-grade inflammation play a key mechanistic role in the disruption of joint homeostasis and cartilage degradation. Although there have been enormous efforts to discover biomarkers of MetS and OA, studies investigating a pathophysiological link between MetS and OA are relatively limited, and no serum blood marker has proved diagnostic so far. OA biomarkers that are necessary to discriminate and diagnose early disease remain to be elicited, explained in part by limited prospective studies, and therefore limited tools available to utilize in any prognostic capacity. Biomarker validation projects have been established by the Biomarker Consortium to determine biochemical markers demonstrating predictive validity for knee OA. Given that the metabolic constituents of MetS are treatable to varying extents, it stands to reason that treating these, and monitoring such treatment, may help to mitigate deleterious links with OA development. This narrative review will describe the current state of biomarker identification and utility in OA associated with MetS. We discuss the pathophysiological mechanisms of disease according to constituent pathologies of MetS and how identification of biomarkers may guide future investigation of novel targets.

IL-1β inhibition combined with cholesterol-lowering therapies decreases synovial lining thickness and spontaneous cartilage degeneration in a humanized dyslipidemia mouse model

INTRODUCTION

Both systemic inflammation and dyslipidemia contribute to osteoarthritis (OA) development and have been suggested as a possible link between metabolic disease and OA development. Recently, the CANTOS trial showed a reduction in knee and hip replacements after inhibition of IL-1β in patients with a history of cardiovascular disease and high inflammatory risk. In this light, we investigated whether inhibition of IL-1β combined with cholesterol-lowering therapies can reduce OA development in dyslipidemic APOE∗3Leiden mice under pro-inflammatory dietary conditions.

MATERIALS AND METHODS

Female ApoE3∗Leiden mice were fed a cholesterol-supplemented Western-Type diet (WTD) for 38 weeks. After 14 weeks, cholesterol-lowering and anti-inflammatory treatments were started. Treatments included atorvastatin alone or with an anti-IL1β antibody, and atorvastatin combined with proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitor alirocumab without or with the anti-IL1β antibody. Knee joints were analyzed for cartilage degradation, synovial inflammation and ectopic bone formation using histology at end point.

RESULTS

Cholesterol-lowering treatment successfully decreased systemic inflammation in dyslipidemic mice, which was not further affected by inhibition of IL-1β. Synovial thickening and cartilage degeneration were significantly decreased in mice that received cholesterol-lowering treatment combined with inhibition of IL-1β (P < 0.01, P < 0.05, respectively) compared to mice fed a WTD alone. Ectopic bone formation was comparable between all groups.

CONCLUSION

These results indicate that inhibition of IL-1β combined with cholesterol-lowering therapy diminishes synovial thickening and cartilage degeneration in mice and may imply that this combination therapy could be beneficial in patients with metabolic inflammation.

[Influence of chronic pain in osteoarthritis on the risk of cardiovascular diseases and modern methods of drug prevention]

The purpose of the review of scientific medical literature was to evaluate the data of the epidemiology of osteoarthritis (OA) and cardiovascular diseases (CVD) with the analysis of risk factors, pathophysiological and pathobiochemical mechanisms of the relationship between OA and the risk of developing CVD in the presence of chronic pain, modern strategies for screening and management of this cohort of patients, the mechanism of action and pharmacological effects of chondroitin sulfate (CS). Conclusions were drawn about the need for additional clinical and observational studies of the efficacy and safety of the parenteral form of CS (Chondroguard) in patients with chronic pain in OA and CVD, improvement of clinical recommendations for the treatment of chronic pain in patients with OA and cardiovascular risk, with special attention to interventions that eliminate mobility restrictions in patients and the inclusion of basic and adjuvant therapy with DMOADs to achieve the goals of multipurpose monotherapy in patients with contraindications to standard therapy drugs.

Metformin attenuates high-fat diet induced metabolic syndrome related osteoarthritis through inhibition of prostaglandins

High-fat diet induces bone marrow inflammation and osteoarthritis phenotype in knee joint, but the underlying mechanisms is unknown. Here, we report that high-fat diet induces aberrant bone formation and cartilage degeneration in knee joint. Mechanistically, a high-fat diet increases the number of macrophages and the secretion of prostaglandins in subchondral bone, promoting bone formation. Metformin treatment is able to decrease the number of macrophages and also the level of prostaglandins induced by high-fat diet in subchondral bone. Importantly, metformin rescues aberrant bone formation and cartilage lesions by decreasing the number of osteoprogenitors and type-H vessels, which also results in relief of osteoarthritis pain response. Thus, we demonstrate prostaglandins secreted by macrophages may be a key reason for high-fat diet induced aberrant bone formation and metformin is a promising therapy for high-fat diet induced osteoarthritis.