Association between leukocyte telomere length and angiogenic cytokines in knee osteoarthritis

Connecting the Dots: Telomere Shortening and Rheumatic Diseases

Telomeres, repetitive sequences located at the extremities of chromosomes, play a pivotal role in sustaining chromosomal stability. Telomerase is a complex enzyme that can elongate telomeres by appending telomeric repeats to chromosome ends and acts as a critical factor in telomere dynamics. The gradual shortening of telomeres over time is a hallmark of cellular senescence and cellular death. Notably, telomere shortening appears to result from the complex interplay of two primary mechanisms: telomere shelterin complexes and telomerase activity. The intricate interplay of genetic, environmental, and lifestyle influences can perturb telomere replication, incite oxidative stress damage, and modulate telomerase activity, collectively resulting in shifts in telomere length. This age-related process of telomere shortening plays a considerable role in various chronic inflammatory and oxidative stress conditions, including cancer, cardiovascular disease, and rheumatic disease. Existing evidence has shown that abnormal telomere shortening or telomerase activity abnormalities are present in the pathophysiological processes of most rheumatic diseases, including different disease stages and cell types. The impact of telomere shortening on rheumatic diseases is multifaceted. This review summarizes the current understanding of the link between telomere length and rheumatic diseases in clinical patients and examines probable telomere shortening in peripheral blood mononuclear cells and histiocytes. Therefore, understanding the intricate interaction between telomere shortening and various rheumatic diseases will help in designing personalized treatment and control measures for rheumatic disease.

Roles of chromatin and genome instability in cellular senescence and their relevance to ageing and related diseases

Ageing is a complex biological process in which a gradual decline in physiological fitness increases susceptibility to diseases such as neurodegenerative disorders and cancer. Cellular senescence, a state of irreversible cell-growth arrest accompanied by functional deterioration, has emerged as a pivotal driver of ageing. In this Review, we discuss how heterochromatin loss, telomere attrition and DNA damage contribute to cellular senescence, ageing and age-related diseases by eliciting genome instability, innate immunity and inflammation. We also discuss how emerging therapeutic strategies could restore heterochromatin stability, maintain telomere integrity and boost the DNA repair capacity, and thus counteract cellular senescence and ageing-associated pathologies. Finally, we outline current research challenges and future directions aimed at better comprehending and delaying ageing.

Sex-specific differences in telomere length of patients with primary knee osteoarthritis

Accelerated telomere shortening is associated with age-related diseases, including osteoarthritis (OA). We aimed to determine the relative telomere length (TL) in leukocytes and cartilage of patients with primary knee OA and to investigate factors that may affect TL in OA. Relative TL measurements were performed using qPCR in leukocytes of 612 individuals (310 patients with primary knee OA undergoing total knee arthroplasty (TKA) and 302 unaffected controls). We also analysed cartilage in 57 of the 310 OA patients, measuring relative TL in severely affected and less affected (control) cartilage collected from the same knee. Cartilage TLs were compared to leukocyte TLs in all 57 patients. A significant sex-by-disease-status interaction was found in regard to relative TL. Controlling for age, the average difference of leukocyte TL between female OA patients versus female controls was 0.217 units greater than that between male OA patients versus male controls (95% CI; [0.014, 0.421]). Relative TL comparison of severely and less affected cartilage samples from the same joint showed attrition of telomeres corresponding to disease severity (0.345 mean TL difference with 95% CI of [0.151, 0.539]) in the joint. We also noted that both severely and less affected cartilage had shorter telomeres than leukocytes collected from the same patient. Severe and moderate pain in OA patients was associated with shorter TL in leukocytes, but there was no association with depression or smoking in leukocytes and cartilage. Our study indicates that sex is an important factor in OA contributing to leukocyte and cartilage TL and that pain in OA shows an inverse association only with leukocyte TL.

Circulating leptin level in osteoarthritis and associations between leptin receptor polymorphisms and disease susceptibility: A meta-analysis

OBJECTIVE

This study aimed to systemically review the evidence on the relationship between the circulating leptin levels and osteoarthritis (OA), and the association between leptin and leptin receptor (LEPR) polymorphisms and OA susceptibility.

METHODS

To find relevant papers (up to February 2023) examining the association between circulating leptin levels, LEPR polymorphisms, and OA, the PUBMED, EMBASE, and Cochrane databases were searched. We performed a meta-analysis to examine the levels of synovial and serum/plasma leptin in OA patients compared with healthy controls, as well as the relationship between OA and LEPR polymorphisms.

RESULTS

Data from 15 investigations, totaling 2197 patients with OA and 2546 controls, were included in the meta-analysis. There were statistically significant differences in the levels of circulating leptin between the OA and control groups (standardized mean difference [SMD] 2.178, 95% confidence interval [CI] 1.208-3.139, P = 0.001). Leptin levels were also substantially greater in European, Asian, and Arab groups among OA patients. After adjusting for age, sex, and/or body mass index, the leptin levels of patients with OA were significantly higher. Similarly, regardless of sample size (n < 100 and n ≥ 100) or year of publication, leptin levels were considerably higher in the OA group. In addition, the synovial leptin level was greater in the OA group than in the control group (SMD 0.783; 95% CI 0.247-1.319, P = 0.004). In the LEPR rs1137101 polymorphism, the OA and AA genotypes were significantly associated (odds ratio 0.282, 95% CI 0.126-0.629, P = 0.002), according to the meta-analysis. Ethnic stratification revealed an association between OA and the LEPR rs1137101 AA genotype in Asian and Arab populations.

CONCLUSION

The results of this meta-analysis indicate that patients with OA had considerably greater levels of circulating leptin than did control individuals. In addition, synovial leptin levels were greater in OA patients than in healthy individuals, and the LEPR rs1137101 polymorphism was linked to an increased risk of developing OA. These results imply that leptin participates in the onset and progression of OA.

Factors affecting decision-making for knee arthroplasty in patients with osteoarthritis

OBJECTIVE

Identifying factors affecting decision-making for knee arthroplasty in patients with knee osteoarthritis is critically important for pain relief, improving in knee function and reaching an optimal outcome. When decision-making is hurried or delayed, surgery may not occur in time, which complicates the surgery and increases its complications. This study was conducted to investigate the factors influencing decision-making for knee arthroplasty.

METHODS

This study is a qualitative study and inductive content analysis method. This study enrolled 22 patients undergoing knee arthroplasty selected through purposive sampling. Data were collected through semi-structured in-depth interviews and analyzed using inductive content analysis.

RESULTS

Data analysis yielded three categories: hope to return to normal life, encouragement and recommendations, and trust and assurance.

CONCLUSION

To make better treatment-related decisions and achieve better outcomes based on the patient's values and wishes, it is necessary for the treatment team to increase its interactions and establish stronger communication with patients to make their expectations more realistic and help them understand the risks. They should also make efforts to increase patients' knowledge about the advantages and disadvantages of surgery and clarify what is important to them in decision-making.

Telomere Length and Risk of Incident Fracture and Arthroplasty: Findings From UK Biobank

We investigated independent associations between telomere length and risk of fracture and arthroplasty in UK Biobank participants. Leukocyte telomere length (LTL) was measured in baseline samples using a validated polymerase chain reaction (PCR) method. We used, in men and women separately, Cox proportional hazards models to calculate the hazard ratio (HR) for incident fracture (any, osteoporotic) or arthroplasty (hip or knee) over 1,186,410 person-years of follow-up. Covariates included age, white cell count, ethnicity, smoking, alcohol, physical activity, and menopause (women). In further analyses we adjusted for either estimated bone mineral density (eBMD) from heel quantitative ultrasound, handgrip strength, gait speed, total fat mass (bioimpedance), or blood biomarkers, all measured at baseline (2006-2010). We studied 59,500 women and 51,895 men, mean ± standard deviation (SD) age 56.4 ± 8.0 and 57.0 ± 8.3 years, respectively. During follow-up there were 5619 fractures; 5285 hip and 4261 knee arthroplasties. In confounder-adjusted models, longer LTL was associated with reduced risk of incident knee arthroplasty in both men (HR/SD 0.93; 95% confidence interval [CI], 0.88-0.97) and women (0.92; 95% CI, 0.88-0.96), and hip arthroplasty in men (0.91; 95% CI, 0.87-0.95), but not women (0.98; 95% CI, 0.94-1.01). Longer LTL was weakly associated with reduced risk of any incident fracture in women (HR/SD 0.96; 95% CI, 0.93-1.00) with less evidence in men (0.98; 95% CI, 0.93-1.02). Associations with incident outcomes were not materially altered by adjustment for heel eBMD, grip strength, gait speed, fat mass, or blood biomarker measures. In this, the largest study to date, longer LTL was associated with lower risk of incident knee or hip arthroplasty, but only weakly associated with lower risk of fracture. The relative risks were low at a population level, but our findings suggest that common factors acting on the myeloid and musculoskeletal systems might influence later life musculoskeletal outcomes. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

The Association of Angiopoietin-2 1064 C/T Rs3020221 Gene Polymorphism with Knee Osteoarthritis

Osteoarthritis (OA) is a common type of arthritis, affecting millions of people around the world. Angiopoietin-2 (Angpt-2) has a role in the development of chronic inflammatory diseases. We aimed to assess the serum Angpt-2 levels in knee OA patients and to investigate the association of Angpt-2 gene polymorphism(rs3020221 C/T) with knee OA susceptibility and severity. Angiopoietin-2(rs3020221C/T) gene polymorphism was identified in 254 knee OA patients and 227 healthy controls using real-time polymerase chain reaction. Serum Angpt-2 was measured using ELISA. The Arabic version of the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index and Kellgren-Lawrence (KL) grading score were used to assess the clinical and radiological severity of OA and their relationship with Angpt-2(rs3020221C/T) gene polymorphism was investigated. Serum Angpt-2 levels were significantly higher in knee OA patients than in the controls (P = .001). OA patients with C/T genotype had a four times greater risk of developing OA than other genotypes (OR = 4.39, 95% CI = 2.85-6.76). Additionally, the T allele presented more in OA patients 224/508 (44%) with two times risk of developing OA (OR = 1.86, 95% CI = 1.43-2.43, p = .001). Angpt-2 SNP (rs3020221C/T) genotype C/T was significantly associated with elevated serum Angpt-2 levels (14.15 ± 5.62 ng/ml). The serum Angpt-2 levels are significantly elevated in OA patients and Angpt-2 gene polymorphism (rs3020221 C/T) may be a risk factor for OA development and both are associated with the severity of knee OA. Carriers of the C/T genotype have a significantly higher serum Angpt-2 levels and a greater risk of developing OA.

Telomere length in patients with osteoarthritis: a systematic review and meta-analysis

BACKGROUND

Telomere length (TL) as a biomarker of aging was associated with many age-related diseases. The relationship between TL and osteoarthritis (OA), the most common form of joint diseases, had been investigated in a number of studies, but with the result inconsistent.

AIMS

The purpose of this study was to systematically evaluate the relationship between TL and OA.

METHODS

Until January 1, 2021, PubMed, Web of Science and Cochrane Library were comprehensively retrieved for relevant literatures. Quality of included literature was assessed using the Newcastle-Ottawa Scale (NOS) assessment scale. The pooled standard mean difference (SMD) with 95% confidence interval (CI) of Leukocytes TL was calculated using random-effect model. Subgroup analysis and meta-regression were used to investigate the potential source of heterogeneity.

RESULTS

Six original studies containing 678 OA patients and 1457 healthy controls were included in this meta-analysis. All six included studies were case-control designed. Pooled results showed that patients with OA had a shorter TL in peripheral blood leukocytes (PBLs) compared with healthy controls, (SMD = - 0.32, 95% CI - 0.57 to - 0.06, Z = - 2.45, P = 0.014). Subgroup and meta-regression analysis showed that sex ratio and body mass index (BMI) were possible sources of heterogeneity. Publication bias was not observed.

CONCLUSION

The TL of PBLs in patients with OA was shorter than that of healthy controls, suggesting that PBLs TL may be closely associated with the pathogenesis and progression of OA.

Senescent skeletal cells cross-talk with synovial cells plays a key role in the pathogenesis of osteoarthritis

Osteoarthritis (OA) has been recognized as an age-related degenerative disease commonly seen in the elderly that affects the whole “organ” including cartilage, subchondral bone, synovium, and muscles. An increasing number of studies have suggested that the accumulation of senescent cells triggering by various stresses in the local joint contributes to the pathogenesis of age-related diseases including OA. In this review, we mainly focus on the role of the senescent skeletal cells (chondrocytes, osteoblasts, osteoclasts, osteocyte, and muscle cells) in initiating the development and progression of OA alone or through cross-talk with the macrophages/synovial cells. Accordingly, we summarize the current OA-targeted therapies based on the abovementioned theory, e.g., by eliminating senescent skeletal cells and/or inhibiting the senescence-associated secretory phenotype (SASP) that drives senescence. Furthermore, the existing animal models for the study of OA from the perspective of senescence are highlighted to fill the gap between basic research and clinical applications. Overall, in this review, we systematically assess the current understanding of cellular senescence in OA, which in turn might shed light on the stratified OA treatments.

Telomere dysfunction in ageing and age-related diseases

Ageing organisms accumulate senescent cells that are thought to contribute to body dysfunction. Telomere shortening and damage are recognized causes of cellular senescence and ageing. Several human conditions associated with normal ageing are precipitated by accelerated telomere dysfunction. Here, we systematize a large body of evidence and propose a coherent perspective to recognize the broad contribution of telomeric dysfunction to human pathologies.

Genetically Predicted Longer Telomere Length May Reduce Risk of Hip Osteoarthritis

Objective: This two-sample Mendelian randomization (MR) study aimed to examine the potential causal association of telomere length (TL) with the risk of osteoarthritis (OA).

Method: The summary-level data for OA was derived from the United Kingdom Biobank cohort, including 50,508 individuals of European descent. Eighteen single nucleotide polymorphisms associated with TL were identified as instrumental variables from the most up-to-date TL genome-wide association study (GWAS) involving over 78,592 individuals of European descent. Based on the GWASs data, MR was performed using established statistical analysis methods including the inverse variance weighted, weighted median, MR-Egger, and MR pleiotropy residual sum and outlier.

Results: Genetically determined TL was not associated with the risk of total OA (IVW odds ratio [OR] = 1.00, 95% confidence interval [CI] = 0.83, 1.21). In subgroup analyses stratified by OA site, no evidence in favor of association between genetically determined TL and knee OA was found (IVW OR = 1.18, 95% CI = 0.89, 1.58). However, using WM method, we observed a limited protective effect of longer TL on the risk of hip OA (OR = 0.60, 95% CI = 0.36–0.99), whereas the results of the IVW (p = 0.931) and MR-PRESSO (p = 0.932) showed that TL had no effect on hip OA.

Conclusions: This study does not support a causal association between TL and total OA. A potential protective association between longer TL and hip OA, though possible, remains less certain.

A genetic determinant of VEGF-A levels is associated with telomere attrition

Telomere length (TL) is a hallmark of cellular aging and is associated with chronic diseases development. The vascular endothelial growth factor A (VEGF-A), a potent angiogenesis factor, is implicated in the pathophysiology of many chronic diseases. The aim of the present study was to investigate the associations between VEGF-A and TL.

TL in leukocytes (LTL) and skeletal muscle (MTL) were measured, 10 VEGF-related polymorphisms genotyped, and VEGF-A plasma concentrations determined in 402 individuals from the TELARTA cohort. LTL/MTL ratio was calculated as an estimate of lifelong TL attrition. Associations between VEGF-A variants and levels, and TL parameters were investigated.

We identified one significant association between the minor allele (T) of rs6993770 variant and LTL/MTL ratio (P=0.001143, β=0.0148, SE=0.004516). The rs6993770 is an intronic variant of the ZFPM2 gene, which is involved in haematopoiesis and the identified association with increased telomere attrition could be due to increased haematopoiesis. No significant epistatic interaction was identified, and no association was found between levels of VEGF-A and any of assessed phenotypes.

We identified a potential common genetic regulation between VEGF-A and telomere length attrition that could be explained by mechanisms of increased hematopoiesis and production of platelets. VEGF-A and TL could play an important role in personalized medicine of chronic diseases and identification of molecular links between them can promote the understanding of their complex implications.

Telomere length determinants in childhood

Telomere length (TL) is a dynamic marker that reflects genetic predispositions together with the environmental conditions of an individual. It is closely related to longevity and a number of pathological conditions. Even though the extent of telomere research in children is limited compared to that of adults, there have been a substantial number of studies providing first insights into child telomere biology and determinants. Recent discoveries revealed evidence that TL is, to a great extent, determined already in childhood and that environmental conditions in adulthood have less impact than first believed. Studies have demonstrated that large inter-individual differences in TL are present among newborns and are determined by diverse factors that influence intrauterine development. The first years of child growth are associated with high cellular turnover, which results in fast shortening of telomeres. The rate of telomere loss becomes stable in early adulthood. In this review article we summarise the existing knowledge on telomere dynamics during the first years of childhood, highlighting the conditions that affect newborn TL. We also warn about the knowledge gaps that should be filled to fully understand the regulation of telomeres, in order to implement them as biomarkers for use in diagnostics or treatment.

Serum levels and gene polymorphisms of angiopoietin 2 in systemic lupus erythematosus patients

This study aimed to discuss association between serum Angiopoietin2 (Ang2) levels, Ang2 gene polymorphisms and systemic lupus erythematosus (SLE) susceptibility. It was carried out by 235 SLE, 342 other inflammatory autoimmune diseases patients and 380 healthy individuals. Serum Ang2 levels was examinated by ELISA, and Ang2 rs12674822, rs1823375, rs1868554, rs2442598, rs3739390 and rs734701 polymorphisms were genotyped using KASP. Increased Ang2 concentrations in SLE patients were observed compared with healthy controls and patients with other inflammatory autoimmune diseases. For allelic contrast, except for rs1823375 (P = 0.058) and rs2442598 (P = 0.523), frequencies of alleles for other polymorphisms were significantly different between SLE patients and controls. Genotypes for rs12674822 (TT), rs1868554 (TT, TA and TT+TA), rs734701 (TT) were negatively correlated with SLE susceptibility (OR = 0.564 for rs12674822; OR = 0.572, OR = 0.625, OR = 0.607 for rs1868554; OR = 0.580 for rs734701). Patients carrying rs1868554 T allele and rs3739390 G allele were more likely to develop hematuria (P = 0.039; P = 0.003). The G allele frequencies of rs12674822 and rs2442598 were higher in SLE patients with proteinuria (P = 0.043; P = 0.043). GC genotype frequency of rs3739390 was higher in patients with ds-DNA (+) (P = 0.024). In summary, SLE had increased serum Ang2, which may be a potential biomarker, and the polymorphisms correlated with SLE.

Telomere shortening is associated with poor physical performance in knee osteoarthritis

Telomere length is a hallmark characteristic of ageing and age-related diseases. Osteoarthritis (OA) is the most common cause of joint pain and physical disability in the elderly. Previous studies have revealed the role of telomere shortening in OA; however, the relationship between telomere length, muscle strength and physical performance in knee OA patients remains unknown. The aim of the present study was to investigate the association of telomere length and physical performance in patients with knee OA. A total of 202 patients with knee OA and 60 healthy controls were enrolled in the study. The quality of life was assessed using Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index and Short Form Health Survey. The skeletal muscle mass was examined using bioelectrical impedance analysis, while the muscle strength was analyzed using hand grip force and isometric knee extension force. The physical performance of patients with knee OA was also investigated using gait speed, Timed up and go test (TUGT), Sit to stand test and 6-min walk test (6MWT). Blood leukocyte relative telomere length (RTL) was assessed using real time quantitative PCR. The mean blood leukocyte RTL in knee OA subjects was significantly lower compared with healthy controls (P<0.001). Knee OA patients with RTL values in the lowest quartile had a slow gait speed (P=0.006) and prolonged TUGT time (P=0.03). Multivariate regression analyses and multiple logistic regression analyses adjusted for age, sex, waist circumference, body mass index, fat mass, skeletal muscle index and the total WOMAC demonstrated that gait speed, TUGT and 6MWT were associated with longer RTL (P-trend<0.05). These findings suggested that poorer physical performance was associated with shorter RTL. Therefore, leukocyte telomere length and physical performance tests, especially gait speed, TUGT and 6MWT, could predict the health status and quality of life in patients with knee OA.

Molecular taxonomy of osteoarthritis for patient stratification, disease management and drug development: biochemical markers associated with emerging clinical phenotypes and molecular endotypes

PURPOSE OF REVIEW

This review focuses on the molecular taxonomy of osteoarthritis from the perspective of molecular biomarkers. We discuss how wet biochemical markers may be used to understand disease pathogenesis and progression and define molecular endotypes of osteoarthritis and how these correspond to clinical phenotypes.

RECENT FINDINGS

Emerging evidence suggests that osteoarthritis is a heterogeneous and multifaceted disease with multiple causes, molecular endotypes and corresponding clinical phenotypes. Biomarkers may be employed as tools for patient stratification in clinical trials, enhanced disease management in the primary care centres of the future and for directing more rational and targeted osteoarthritis drug development. Proximal molecular biomarkers (e.g synovial fluid) are more likely to distinguish between molecular endotypes because there is less interference from systemic sources of biomarker noise, including comorbidities.

SUMMARY

In this review, we have focused on the molecular biomarkers of four distinct osteoarthritis subtypes including inflammatory, subchondral bone remodelling, metabolic syndrome and senescent age-related endotypes, which have corresponding phenotypes. Progress in the field of osteoarthritis endotype and phenotype research requires a better understanding of molecular biomarkers that may be used in conjunction with imaging, pain and functional assessments for the design of more effective, stratified and individualized osteoarthritis treatments.

Telomere length and telomerase activity in osteoporosis and osteoarthritis

Osteoarthritis (OA) and osteoporosis (OP) are associated skeletal pathologies and have as a distinct feature the abnormal reconstruction of the subchondral bone. OA and OP have been characterized as age-related diseases and have been associated with telomere shortening and altered telomerase activity (TA). This review discusses the role of telomeres and telomerase in OA and OP pathologies and focuses on the usability of telomere length (TL) and the rate of telomere shortening as potential disease biomarkers. A number of studies have demonstrated that telomere shortening may contribute to OA and OP as an epigenetic factor. Therefore, it has been claimed that the measurement of TL of chondrocytes and/or peripheral blood cells may be an appropriate marker for the evaluation of the progression of these diseases. However, there is a need to be perform further studies with larger cohorts, with the aim of obtaining objective results and a better understanding of the association between TL, inflammation and aging, in order to provide further insight into the pathophysiology of degenerative joint diseases.

Relative Telomere Length in Blood Leukocytes of Patients with Anterior Cruciate Ligament Injury: A Pilot Study

Introduction: Anterior cruciate ligament (ACL) tear is the most common knee ligament injury, especially in athletes. The objective of this study was to investigate relative telomere length (RTL) in blood leukocytes of patients with ACL injury compared with that of controls.

Materials and Methods: A total of 187 subjects were invited to participate in this study. Ninety-two patients with clinically diagnosed ACL rupture were enrolled. Ninety-five age and gender-matched healthy controls were also recruited. Blood leukocyte RTL were analysed using quantitative real-time polymerase chain reaction.

Results: Patients with ACL rupture had significantly longer relative telomere length than healthy controls (P=0.002). The patients with ACL rupture were classified into two groups according to the sport history of patients which are contact sports and non-contact sports. RTL in patients with non-contact sports was significantly greater than those with contact sports (P=0.006). Moreover, RTL was inversely correlated with body mass index of patients with ACL injury (r=-0.34, P=0.001). Logistic regression analysis indicated that long RTL was associated with a higher risk of ACL rupture.

Conclusion: The present study showed that subjects with ACL rupture had significantly greater telomere length compared with their age and gender-matched controls. This finding may result from the increases in physical activity and overexpression of telomerase which acts as a protective mechanism against ACL injury. RTL in blood leukocytes is associated with a risk of ACL rupture.

Leukocyte Telomere Length in Patients with Radiographic Knee Osteoarthritis

Relative mean telomere sequence amount was determined by quantitative PCR (qPCR) of peripheral blood leukocyte (PBL) samples obtained at recruitment (n = 310) from individuals from the Osteoarthritis (OA) Initiative consortium. Knees were radiologically evaluated according to the Kellgren-Lawrence (KL) score, ranging from 0 to 4, considering a KL grade ≥ 2 as radiographic evidence of OA (n = 124). Telomere size decreased as baseline KL score increased, being significantly shorter in subjects with KL ≥2 (Mann-Whitney U-test, P < 0.0001). PBL telomere size was also associated with age, hypertension, body mass index (BMI) and waist circumference. Nevertheless, logistic regression analysis showed that PBL telomere size was a consistent risk factor for concurrent knee OA, independent of these health parameters. Shorter PBL telomeres may indicate a premature aging status which enhances chondrocyte senescence and degenerative joint disease. Environ. Mol. Mutagen. 60:298-301, 2019. © 2018 Wiley Periodicals, Inc.

Incident hand OA is strongly associated with reduced peripheral blood leukocyte telomere length

OBJECTIVE

To evaluate the relationship of telomere length to the prevalence and incidence of hand osteoarthritis in a longitudinal cohort.

DESIGN

We conducted a cross-sectional and longitudinal analysis of data from a subset of participants in the Osteoarthritis Initiative (OAI) recruited between February 2004 and May 2006. 274 individuals were eligible for the study based on availability of both baseline and 48-month hand radiographs and peripheral blood leucocyte telomere length data. Mean telomere length of peripheral blood leukocytes (PBL)s from the DNA samples was determined using a validated quantitative polymerase chain reaction (PCR)-based assay, and hand radiographs were analyzed and graded using the Kellgren-Lawrence scale.

RESULTS

In joint -level analyses, prevalent Interphalangeal Joint Osteoarthritis (IPJOA) was significantly associated with PBL telomere length in the baseline sample in unadjusted analyses (RR = 2.84; 95% CI:0.87-9.29) or in models adjusted for age, sex, and body mass index (aRR = 1.10; 95% CI: 0.96-1.27). The association in crude and adjusted analyses appeared slightly stronger with incident IPJOA, especially in the subset with normal hands at baseline (aRR = 1.62; 95% CI: 1.02-2.57). PBL telomere length was also associated with prevalent HOA at baseline (significant in unadjusted analysis: RR = 1.22; 95% CI 1.06-1.42), but not after adjusting for covariates: aRR = 1.12; 95% CI: 0.96-1.30). The magnitude of association was stronger for incident HOA, especially incident symptomatic HOA (aRR = 1.53; 95% CI: 1.09-2.15).

CONCLUSIONS

In summary, the results of this exploratory analysis are confirmatory of previous work showing a cross-sectional relationship between telomere length and HOA and add to the field by demonstrating an even stronger association with incident IPJOA, both radiographic and symptomatic.

Predictors of Osteoarthritis Pain: the Importance of Resilience

PURPOSE OF REVIEW

Osteoarthritis (OA) is one of the most common and disabling forms of arthritis worldwide, with joint pain being a primary symptom. Given that clinical symptoms often show poor concordance with tissue damage in OA, processes other than joint remodeling likely play a role in the condition. Using the biopsychosocial model of pain as a guiding framework, the purpose of this review is to highlight the extra-articular mechanisms that contribute to pain and dysfunction in OA, with a specific focus on resilience.

RECENT FINDINGS

Whereas previous research has mostly focused on risk factors for worsening of OA pain, recently emerging evidence places greater emphasis on the identification of protective mechanisms that enhance pain adaptation and palliate the negative effects of joint pain. In view of this new and important research, more emphasis should be placed on endogenous pain modulation and, in particular, pain attenuation. The result of such work could serve as a basis for optimizing treatment in the OA population.

Postoperative Changes in the Systemic Inflammatory Milieu in Older Surgical Patients

Dysregulated inflammation is a central component of wound healing following surgery. We prospectively enrolled older patients (n = 25, age 65 ± 7 years) undergoing elective total knee arthroplasty or total hip arthroplasty secondary to advanced osteoarthritis (OA) and healthy controls (n = 48). Inflammatory, proangiogenic (vascular endothelial growth factor [VEGF], monocyte chemoattractant protein-1 [MCP-1], and interleukin-8 [IL-8]), and antiangiogenic (interferon γ [IFN-γ] and IL-4) factors were measured using a high-sensitivity biochip. Patients with OA had significantly higher baseline VEGF (10.5 ± 1.2 pg/mL vs 4.8 ± 0.2 pg/mL, P < .001), MCP-1 (130.6 ± 7.7 pg/mL vs 88.6 ± 3.9 pg/mL, P < .0001), and IL-8 (4.0 ± 0.5 pg/mL vs 2.6 ± 0.1 pg/mL, P < .05). Postoperatively, the levels of VEGF (10.5 ± 1.2 pg/mL vs 18.8 ± 1.5 pg/mL, P < .001) and MCP-1 (130.6 ± 7.7 pg/mL vs 153.1 ± 11.5 pg/mL, P < .05) increased significantly. Baseline and postoperative MCP-1 levels correlated positively and significantly with age. The levels of IFN-γ and IL-4 (which has anti-inflammatory properties) did not significantly differ at baseline in patients with OA compared to controls and did not significantly rise postoperatively. We conclude that systemic levels of pro-inflammatory and angiogenic proteins are increased in patients with OA and rise further postoperatively, while proteins that restrain inflammation and angiogenesis do not coordinately rise. These findings implicate imbalance in inflammatory pathways in OA that may contribute to its pathobiology.