Urinary CTX-II Research Articles

A non-invasive measure of bone growth in mammals: Validating urinary CTX-I as a bone resorption marker through long-bone growth velocity in bonobos.

Assessing bone growth trajectories in mammals is crucial for understanding life history dynamics, but the quantification of bone growth in natural settings can be challenging. Bone resorption markers that can be measured in urine, such as C-telopeptide of type I collagen (CTX-I), offer a non-invasive solution to assess bone growth. Although measurement of urinary CTX-I levels has been applied extensively in human studies, its use in other species is so far limited to a few clinical studies. To validate urinary CTX-I as a bone resorption marker under less controlled conditions, we investigated within-individual day-to-day variation, diurnal patterns, and sex and age-specific variation in zoo-housed bonobos (Pan paniscus). We then also correlated urinary CTX-I levels with forearm growth velocity measures. We found a day-to-day variability in urinary CTX-I levels of around 25%, comparable to human variation. Diurnally, CTX-I levels decreased, aligning with observations in humans and other species. Both sexes showed an age-related decline in urinary CTX-I levels, with a steady decrease after the age of 10 years. Additionally, we found a positive correlation between forearm growth velocity and urinary CTX-I levels across age in female, but not in male, bonobos. Our results demonstrate that urinary CTX-I levels are a meaningful measure of bone growth and highlight its potential to examine bone growth trajectories also in wild populations to investigate life history dynamics.

Effect of high in comparison to low dairy intake intervention on markers of bone and cartilage remodeling and phosphate metabolism in healthy adults with overweight.

In the ageing population, issues with bone and joint health are highly prevalent. Both beneficial and potential risks of dairy products on bone and joint health are reported in epidemiological studies. Furthermore, the phosphorus (P) load from dairy could potentially lead to unfavorable changes in P metabolism. To investigate the effect of dairy intake on markers of bone and joint metabolism and P metabolism in an intervention study with high and low dairy intake. In a post hoc analysis of a randomized cross-over trial with overweight adults, the effect of a standardized high dairy intake [HDI (5-6 dairy portions per day) versus low dairy intake (LDI, ≤ 1 dairy portion/day)] for 6weeks on markers of bone and joint health was assessed using enzyme-linked immunosorbent assays and electrochemiluminescence immunoassays. Markers indicative for cartilage breakdown, including urinary CTX-II, serum COMP and 4-hydroxyproline, and markers indicative for bone remodeling, such as serum CTX-I, PTH, 25(OH)D, osteocalcin, P1NP and FGF23, were investigated using linear mixed models. Furthermore, changes in P metabolism, including the main phosphate-regulating hormone FGF23 were explored. This study was completed by 46 adults (57% female, age 59 ± 4 years, BMI 28 ± 2kg/m2). Following HDI, markers such as urinary CTX-II excretion, COMP, 25(OH)D, PTH and CTX-I were significantly lower after HDI, as compared to LDI. For example, CTX-II excretion was 1688ng/24h at HDI, while it was 2050ng/24h at LDI (p < 0.001). Concurrently, P intake was higher at HDI than at LDI (2090 vs 1313mg/day, p < 0.001). While plasma P levels did not differ (1.03 vs 1.04mmol/L in LDI, p = 0.36), urinary P excretion was higher at HDI than at LDI (31 vs 28mmol/L, p = 0.04). FGF23 levels tended to be higher at HDI than at LDI (76.3 vs. 72.9 RU/mL, p = 0.07). HDI, as compared to LDI, reduced markers that are indicative for joint and bone resorption and bone turnover. No changes in P metabolism were observed. This trial was registered at https://trialsearch.who.int/Trial2.aspx?TrialID=NTR4899 as NTR4899.

Plasma Cartilage Acidic Protein 1 Measured by ELISA Is Associated With the Progression to Total Joint Replacement in Postmenopausal Women.

To investigate the association of plasma cartilage acidic protein 1 (CRTAC1), a novel biochemical marker of osteoarthritis (OA), and total joint replacement (TJR) in postmenopausal women. The association of plasma CRTAC1 with the incidence of TJR was investigated in a prospective cohort including 478 postmenopausal women. A total of 38 women underwent a TJR for OA during a median follow-up of 18 years. Every one of the TJR cases were age- and BMI (kg/m2)-matched with 2 controls with no TJR from the same cohort. Plasma CRTAC1 was measured before TJR. The association between CRTAC1 and TJR incidence was investigated by conditional logistic regression. Increased CRTAC1 was associated with a higher risk of TJR with an odds ratio (OR) of 1.80 (95% CI 1.11-2.92) for 1 SD increase, which remained significant after adjusting for Western Ontario and McMaster Universities Osteoarthritis Index, knee OA baseline severity (Kellgren-Lawrence grade), hip OA, and hip bone mineral density. Urinary crosslinked C-telopeptide of type II collagen (CTX-II) was also associated with a higher risk of TJR with an adjusted OR of 1.83 (95% CI 1.11-3.00). When CRTAC1 and CTX-II were included in the same model, both markers were significantly associated with TJR with similar ORs. CRTAC1 is a new risk indicator of TJR for OA in postmenopausal women. Combined with knee and hip OA and CTX-II, it may help to identify subjects at risk for TJR.

Subclinical synovial proliferation in patients with severe haemophilia A: The value of ultrasound screening and biochemical markers.

Subclinical bleeding and inflammation play a role in progression of haemophilic arthropathy. Synovial proliferation is predictive of joint bleeding and its early detection may guide treatment changes and prevent arthropathy progression. This study evaluated the prevalence of active and inactive subclinical synovial proliferation and investigated potential biochemical blood/urine markers to identify patients with active subclinical synovial proliferation. This cross-sectional study included patients with severe haemophilia A born 1970-2006 who were evaluated during routine clinic visits. Patients with (a history of) inhibitors or recent joint bleeding were excluded. Elbows, knees and ankles were examined for subclinical synovial proliferation by ultrasound and physical examination. Active synovial proliferation was distinguished from inactive synovial proliferation using predefined criteria. Blood/urine biochemical markers (serum osteopontin, sVCAM-1, Coll2-1, COMP, CS846, TIMP, and urinary CTX-II) were compared individually and as combined indexes between patients with and without active synovial proliferation. This cohort consisted of 79 patients with a median age of 31years (range 16.5-50.8years) with 62/79 (78%) of the patients using continuous prophylaxis. The annualized joint bleeding rate over the last 5years was .6 (.2-1.1). Active (17/79, 22%) and inactive subclinical synovial proliferation (17/79, 22%) were both prevalent in this cohort. Biochemical markers were not correlated with active subclinical synovial proliferation. Subclinical synovial proliferation, both active and inactive, was prevalent in patients with severe haemophilia A with access to prophylaxis and would be overlooked without routinely performed ultrasounds. Biochemical markers were unable to identify patients with active subclinical synovial proliferation.

Plasma crtac-1 measured by elisa, predicts the progression to total joint replacement, independently of urinary ctx-ii, in postmenopausal women

Plasma crtac-1 measured by elisa, predicts the progression to total joint replacement, independently of urinary ctx-ii, in postmenopausal women

Sex-specific effects of calving season on joint health and biomarkers in Montana ranchers

BackgroundAgricultural workers have a higher incidence of osteoarthritis (OA), but the etiology behind this phenomenon is unclear. Calving season, which occurs in mid- to late-winter for ranchers, includes physical conditions that may elevate OA risk. Our primary aim was to determine whether OA biomarkers are elevated at the peak of calving season compared to pre-season, and to compare these data with joint health survey information from the subjects. Our secondary aim was to detect biomarker differences between male and female ranchers.MethodsDuring collection periods before and during calving season, male (n = 28) and female (n = 10) ranchers completed joint health surveys and provided samples of blood, urine, and saliva for biomarker analysis. Statistical analyses examined associations between mean biomarker levels and survey predictors. Ensemble cluster analysis identified groups having unique biomarker profiles.ResultsThe number of calvings performed by each rancher positively correlated with plasma IL-6, serum hyaluronic acid (HA) and urinary CTX-I. Thiobarbituric acid reactive substances (TBARS), a marker of oxidative stress, was significantly higher during calving season than pre-season and was also correlated with ranchers having more months per year of joint pain. We found evidence of sexual dimorphism in the biomarkers among the ranchers, with leptin being elevated and matrix metalloproteinase-3 diminished in female ranchers. The opposite was detected in males. WOMAC score was positively associated with multiple biomarkers: IL-6, IL-2, HA, leptin, C2C, asymmetric dimethylarginine, and CTX-I. These biomarkers represent enzymatic degradation, inflammation, products of joint destruction, and OA severity.ConclusionsThe positive association between number of calvings performed by each rancher (workload) and both inflammatory and joint tissue catabolism biomarkers establishes that calving season is a risk factor for OA in Montana ranchers. Consistent with the literature, we found important sex differences in OA biomarkers, with female ranchers showing elevated leptin, whereas males showed elevated MMP-3.

Effects of Greenshell™ mussel intervention on biomarkers of cartilage metabolism, inflammatory markers and joint symptoms in overweight/obese postmenopausal women: A randomized, double-blind, and placebo-controlled trial.

To investigate the effect of whole greenshell mussel (GSM) powder on biomarkers of cartilage metabolism, inflammatory cytokines, and joint symptoms in postmenopausal women with overweight/obesity and joint discomfort. Fifty-five postmenopausal women with overweight/obesity were randomly assigned to receive 3 g/day whole GSM powder or placebo for 12 weeks. Cartilage turnover biomarkers urinary C-telopeptide of type II collagen (CTX-II) and serum cartilage oligomeric matrix protein (COMP) were measured at baseline, week 6 and 12. Plasma cytokines were measured at baseline and week 12. Joint pain and knee-related problems were assessed at baseline and week 12 using a 100 mm Visual Analogue Scale (VAS) and the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire, respectively. Forty-nine participants completed the study (GSM n = 25, placebo n = 24). After 12 weeks, urinary CTX-II showed no significant change over time or between the groups (interaction effect P = 0.1). However, in women with symptomatic knees, a significant difference was noted between the group (treatment effect P = 0.04), as it was lower in the GSM group compared to placebo group at week 6 (P = 0.04) and week 12 (P = 0.03). Serum COMP and plasma cytokines were not affected. GSM supplementation showed greater reduction in the VAS pain score than placebo (-13.2 ± 20.3 vs. -2.9 ± 15.9; P = 0.04). No significant change in KOOS domains between the two groups was observed. Oral supplementation of whole GSM powder at 3 g/day may slow down the degradation of type II collagen in postmenopausal women with symptomatic knees. GSM treatment conferred clinical benefit on overall joint pain. No significant effect was noted for inflammatory cytokines, suggesting that GSM may act within the joint microenvironment rather than at the systemic level. [www.australianclinicaltrials.gov.au/clinical-trialregistries], identifier [ACTRN12620000413921p].

Treatment-Monitoring Capabilities of Serum and Urine Biomarkers for Meniscal Allograft Transplantation in a Preclinical Canine Model

Background: Meniscal allograft transplantation (MAT) has been developed as a treatment for meniscal deficiency. Despite promising outcomes, there are no real-time methods to evaluate graft survivorship and predict functional outcomes. Hypothesis: Assessment of serum and urine biomarkers could be used to develop biomarker panels—prognostic (1- and 3-month postsurgical time points) and diagnostic (6-month time point)—based on strong associations with clinically relevant outcome metrics obtained 6 months after surgery. Study Design: Descriptive laboratory study. Methods: Twelve adult purpose-bred research hounds were included and underwent medial meniscal release to induce meniscal deficiency. Three months after meniscal release surgery, medial menisci were replaced with fresh-frozen meniscus (n = 4), fresh meniscus (n = 4), or fresh meniscotibial osteochondral allograft (n = 4) such that a spectrum of pain and functional outcomes could be anticipated. Serum and urine from all dogs were collected preoperatively and at 1, 3, and 6 months after MAT surgery. Dogs were assessed for pain-related and functional outcomes at the same time points. To develop a prognostic panel of biomarkers, biomarker data from the 1- and 3-month post-MAT surgery time points were used to model 6-month clinical outcomes. A diagnostic panel of biomarkers was developed using data from the 6-month post-MAT surgery to model 6-month clinical outcomes. Primary outcomes for pain and function were visual analog scale (VAS) and operated limb percentage total pressure index (%TPI), respectively. Using random subject effects, linear mixed models were used to develop prognostic biomarker panels, and linear fixed-effect models were used to develop diagnostic biomarker panels, with variance explained for each panel reported (R2) along with individual biomarker relationships. Results: Across prognostic biomarker panels, a panel including serum IL-6, IL-8, IL-10, and IL-18 was fit for the primary functional outcome, operated limb %TPI (R2 = 0.450), whereas a panel including serum CTX-II and OPG was fit for the primary pain-related outcome, VAS (R2 = 0.516). Across diagnostic biomarker panels, a panel including serum MMP-1 and MMP-3 and urine PINP and TIMP-1 was fit for %TPI (R2 = 0.863). Separately, a panel including urine CTX-I, CTX-II, IL-8, MMP-2, and TIMP-1 was fit as diagnostic biomarkers for the VAS for pain (R2 = 0.438). Conclusion: Biomarker panels of selected serum and/or urine proteins can model clinically relevant metrics for function and pain in a preclinical model of MAT. Clinical Relevance: Biomarker panels could be used to provide real-time diagnostic and prognostic data regarding outcomes after MAT.

Paper 33: Serum and Urine Biomarkers for Treatment Monitoring after Meniscal Allograft Transplantation in a Preclinical Canine Model

Objectives:To analyze serum and urine biomarker concentrations for their capabilities in delineating differences in assessments of pain and functional outcomes after meniscus allograft transplantation (MAT) in a preclinical canine model. The study was designed to test the hypothesis that serum and urine biomarkers could be used for prognostic (1- and 3-month post-surgical time points) and diagnostic (6-month time point) assessments, based on strong associations with clinically relevant pain and function outcomes after MAT.Methods:Twelve adult, purpose-bred research hounds were included and underwent medial meniscal release (MR) to induce medial compartment gonarthrosis. Three months following MR, medial MAT was performed using: fresh-frozen meniscus (n=4), fresh meniscus (n=4), or fresh menisco-tibial OCA (n=4). Serum and urine from all dogs were collected preoperatively and at 1, 3, and 6 months following MAT. Validated outcome measures for pain, function, effusion, knee range of motion, and gait kinetics were collected at these same timepoints. To develop a prognostic panel of biomarkers, biomarker data from the 1-month and 3-month post-MAT surgery timepoints were used to model 6-month outcomes. A diagnostic panel of biomarkers was developed using biomarker data from the 6-month post-MAT surgery to model 6-month outcomes.Results:Across prognostic biomarker panels, serum biomarkers were mainly represented. A panel including serum IL-6, IL-8, IL-10, and IL-18 had strong model fit for prognostication of the gait kinetics outcome, operated limb %Total Pressure Index (%TPI) (R2=.45). Whereas, a biomarker panel including serum CTX-II and OPG had strong model fit for prognostication of the primary pain-related outcome, VAS pain (R2=.52). Across diagnostic biomarker panels, a panel including serum MMP-1 and MMP-3 and urine PINP and TIMP-1 had strong model fit as diagnostic biomarkers for %TPI (R2=.86). Whereas, a panel including urine CTX-I, CTX-II, IL-8, MMP-2, and TIMP-1 had strong model fit as diagnostic biomarkers for VAS pain (R2=.44).Conclusions:Biomarker panels of selected serum and/or urine proteins highly correlate with clinically-relevant metrics for pain and function outcomes in a preclinical model of meniscus allograft transplantation.

Biomarker clusters differentiate phenotypes of lumbar spine degeneration and low back pain: The Johnston County Osteoarthritis Project

ObjectiveDescribe the association between biomarkers and lumbar spine degeneration (vertebral osteophytes [OST], facet joint osteoarthritis [FOA], and disc space narrowing [DSN]), for persons with and without low back pain (LBP) and determine whether clusters based on biomarkers differentiate lumbar spine structure with and without LBP. MethodsUsing data from the Johnston County Osteoarthritis Project (2006–2010), we measured serum N-cadherin, Keratin-19, Lumican, CXCL6, RANTES, HA, IL-6, BDNF, OPG, and NPY, and urinary CTX-II. Biomarkers were used to group participants using k-means cluster analysis. Logistic regression models were used to compare biomarker clusters. ResultsThe sample consisted of 731 participants with biospecimens and lumbar spine radiographic data. Three biomarker subgroups were identified: one characterized by structural degenerative changes; another characterized by structural degenerative changes and inflammation, with pain; and a referent cluster with lower levels of biomarkers, pain, and structural degenerative changes. Compared to the referent subgroup, the structural change subgroup was associated with DSN (OR ​= ​1.94, 95% CI 1.30–2.90) and FOA (OR ​= ​1.72, 95% CI 1.12–2.62), and the subgroup with structural degenerative change, inflammation, and pain was associated with OST with LBP (OR ​= ​1.60, 95% CI 1.04–2.46), FOA with LBP (OR ​= ​1.59, 95% CI 1.04–2.45), and LBP (OR ​= ​1.63, 95% CI 1.11–2.41). The subgroup with structural degenerative changes was more likely to have OST (OR ​= ​1.82, 95% CI 1.06–3.13) and less likely to have FOA with LBP (OR ​= ​0.62, 95% CI 0.40–0.96) compared to the group with inflammation and pain. ConclusionClustering by biomarkers may assist in differentiating patients for specific clinical interventions aimed at decreasing LBP.

Biochemical, clinical, demographic and imaging biomarkers for disease progression in knee osteoarthritis.

Aim: To identify prognostic biomarker(s) for knee osteoarthritis (OA) in the Osteoarthritis Initiative (OAI) cohort. Methods: Multilevel regression was used to determine the association between baseline biomarkers and change in biomarkers from baseline to 24 months with clinical and radiographic OA progression over 48months of follow-up. Results: Higher values of baseline urinary CTXII were consistently associated with an increased risk of OA disease progression outcomes: Kellgren & Lawrence grade (odds ratio [OR]: 1.15, 95% CI: 1.03-1.28); medial joint space narrowing (OR: 1.06, 95% CI: 1.02-1.10); lateral osteophytes (OR: 1.05, 95% CI: 1.01-1.10); joint space width (regression coefficient: -0.005, 95% CI: -0.008-0.001); and Western Ontario and McMaster Universities Arthritis Index pain scores (OR: 1.02, 95% CI: 1.01-1.04). Changes in serum PIIANP and serum COMP over 24months were associated with clinical disease progression. Conclusion: Urinary CTXII showed stronger associations with radiographic OA and appears to be a reliable prognostic marker, while changes in other biomarkers were found in early symptomatic OA, supporting the phasic nature of OA.

Different changes in the biomarker C-terminal telopeptides of type II collagen (CTX-II) following intra-articular injection of high molecular weight hyaluronic acid and oral non-steroidal anti-inflammatory drugs in patients with knee osteoarthritis: a multi-center randomized controlled study

We previously reported, based on a multicenter randomized-control study, that the efficacy of intra-articular injections of hyaluronic acid (IA-HA) was not inferior to that of oral non-steroidal anti-inflammatory drugs (NSAIDs) in patients with knee osteoarthritis (OA). However, the molecular effects on the pathophysiology of knee OA remain unclear. C-terminal telopeptides of type II collagen (CTX-II) is reported to primarily originate from the interface between articular cartilage and subchondral bone, which is a site of potential remodeling in OA. We performed a predefined sub-analysis of the previous study to compare the changes of urinary CTX-II (uCTX-II) in response to IA-HA to those in response to NSAID for knee OA. A total of 200 knee OA patients were registered from 20 hospitals and randomized to receive IA-HA (2,700kDa HA, 5 times at 1-week intervals) or NSAID (loxoprofen sodium, 180mg/day) for 5weeks. The uCTX-II levels were measured before and after treatment. The uCTX-II levels were significantly increased by IA-HA treatment (337.7±193.8 to 370.7±234.8ng/μmol Cr) and were significantly reduced by NSAID treatment (423.2±257.6 to 370.3±250.9ng/μmol Cr). The %changes of uCTX-II induced by IA-HA (11.6±29.5%) and NSAID (-9.0±26.7%) was significantly different (between-group difference: 20.6, 95% confidence intervals: 10.6 to 30.6). While both IA-HA and NSAID improved symptoms of knee OA, uCTX-II levels were increased by IA-HA and reduced by NSAIDs treatment, suggesting these treatments may improve symptoms of knee OA through different modes of action.

The Efficacy and Safety of Multiple Dose Regimens of Kudzu (Pueraria lobata) Root Extract on Bone and Cartilage Turnover and Menopausal Symptoms.

Background: Menopause is associated with detrimental changes in turnover of bone and cartilage and a variety of symptoms with negative impact on the quality of life. Naturally occurring isoflavones from Radix Pueraria lobata, Kudzu root, may possess chondroprotective and symptom-relieving properties, but efficacy and safety of dosing and dose frequencies required for pharmacological action is unclear. Purpose: This clinical trial evaluates the efficacy on bone and cartilage turnover, menopausal symptoms, and safety of five dose regimens of Kudzu root extract administered either once, twice or three times daily in women with at least mild menopausal symptoms. Materials and Methods: Fifty postmenopausal women were randomized equally into five different dose regimen groups of Kudzu root extract in a four-week, parallel group, open-label, single-center, exploratory study design. Biomarkers CTX-I and CTX-II reflecting bone and cartilage degradation, respectively, were assessed in blood samples and 24-h urine samples. Change from baseline in the Menopause Rating Scale (MRS) and subscales was evaluated. Safety endpoints were frequency of adverse events, changes in hematology and safety chemistry data, vital signs and electrocardiogram. Results: Fifty women (Age 54.2 years, SD: 2.9) were randomized. After 4 weeks of treatment, biomarkers of bone resorption and cartilage degradation were statistically significantly reduced from baseline levels in the group receiving two capsules three times a day, serum/urine CTX-I (−18.4%, 95% CI: −8.1 to −27.5, p = 0.001/−34.2%, 95% CI: −21.6 to −44.7, p < 0.0001), urine CTX-II (−17.4% 95% CI: −2.5 to −30.0, p = 0.02). The observed effects were consistent across study groups but appeared to favour three times daily dosing. Four weeks of treatment led to statistically significant reductions in the MRS Total Score (p < 0.0001–0.03) in four out of five treatment groups. Kudzu root extract was well tolerated in all dose regimens, and no serious adverse events were reported. Conclusion: The results indicate that Kudzu extract may possess beneficial effects on bone and cartilage health and may be a promising natural alternative to existing treatments for menopausal symptoms. Kudzu root extract was well tolerated for short-term treatment of mild to severe menopausal symptoms in women in all tested doses and dose frequencies.

Biomarkers of joint metabolism and bone mineral density are associated with early knee osteoarthritis in premenopausal females.

Biomarkers of bone and cartilage metabolism were proposed as early diagnosis indicators for knee osteoarthritis (OA), however, which were influenced by disease stage, age, and menopause state. Accurate diagnosis indicators are eagerly awaited. The current study aims to investigate associations of joint metabolism biomarkers and bone mineral density (BMD) with early knee OA in males and premenopausal females before age 50years. A total of 189 patients aged before 50years with early knee OA and 152 healthy participants were enrolled. Levels of bone biomarkers (PINP, OC, and CTX-I) and cartilage biomarkers (PIIANP, COMP, CTX-II, and MMP-3) were assessed. BMD was measured at the lumbar, femoral neck, and hip. Multivariate regression analyses were performed to evaluate the relationship between biomarkers, BMD, and early knee OA. Serum COMP, urine CTX-II and BMD at femoral neck and hip were increased in premenopausal patients as compared to control; with serum PINP and OC reduced. Meanwhile, serum COMP, urine CTX-II, and BMD at femoral neck and hip showed positive associations with premenopausal early knee OA, while serum PINP had negative association. However, in male patients, only serum COMP was higher than control, and no association of biomarkers or BMD was found with early knee OA. The joint metabolism biomarkers and BMD showed multiple associations with early knee OA in premenopausal females, but not in males aged before 50years. It was suggested that sex differences should be taken into account when evaluating cartilage and bone metabolism in early knee OA. Key Points • The joint metabolism biomarkers and BMD are associated with early knee OA in premenopausal females, but not in males aged before 50years. • Sex differences should be taken into account when evaluating cartilage and bone metabolism in early knee OA.

An Anterior Cruciate Ligament Rupture Increases Levels of Urine N-terminal Cross-linked Telopeptide of Type I Collagen, Urine C-terminal Cross-linked Telopeptide of Type II Collagen, Serum Aggrecan ARGS Neoepitope, and Serum Tumor Necrosis Factor–α

Background: An anterior cruciate ligament (ACL) rupture results in an increased risk of developing knee osteoarthritis (OA) at an early age. Before clinical signs become apparent, the OA process has already been initiated. Therefore, it is important to look at the cascade of changes, such as the activity of cytokines and proteases, which might be associated with the later development of OA. Purpose: To compare biomarker levels in patients with a recent ACL rupture with those in controls with a healthy knee and to monitor biomarker levels over 2 years after an ACL rupture. Study Design: Descriptive laboratory study. Methods: Patients were enrolled after an ACL tear was identified. Serum and urine samples were collected at the time of enrollment in the study (3-25 weeks after the injury) and then at 14 and 27 months after the injury between January 2009 and November 2010. Reference samples were obtained from participants with healthy knees. The following biomarkers were measured with immunological assays: aggrecan ARGS neoepitope (ARGS-aggrecan), tumor necrosis factor–α (TNF-α), interferon-γ, interleukin (IL)–8, IL-10, IL-13, N-terminal cross-linked telopeptide of type I collagen (NTX-I), and C-terminal cross-linked telopeptide of type II collagen (CTX-II). Results: Samples were collected from 152 patients with an acute ACL rupture, who had a median age of 25 years (interquartile range [IQR], 21-32 years). There were 62 urine reference samples (median age, 25 years [IQR, 22-36 years]) and 26 serum reference samples (median age, 35 years [IQR, 24-39 years]). At a median of 11 weeks (IQR, 7-17 weeks) after trauma, serum levels of both ARGS-aggrecan and TNF-α were elevated 1.5-fold (P < .001) compared with reference samples and showed a time-dependent decrease during follow-up. Urine NTX-I and CTX-II concentrations were elevated in an early phase after trauma (1.3-fold [P < .001] and 3.7-fold [P < .001], respectively) compared with reference samples, and CTX-II levels remained elevated compared with reference samples at 2-year follow-up. Strong correlations were found between serum ARGS-aggrecan, urinary NTX-I, and urinary CTX-II (rs = 0.57-0.68). Conclusion: In the first few months after an ACL injury, there was a measurable increase in serum levels of ARGS-aggrecan and TNF-α as well as urine levels of NTX-I and CTX-II. These markers remained high compared with those of controls with healthy knees at 2-year follow-up.

The inverse association of body adiposity index and bone health in the older adults: A report from a developing country.

The ageing process influences body composition and could be related to bone health. The current study was set out to evaluate the association between body adiposity index (BAI) and bone health in older adults. This is a cross-sectional study performed on 178 elderly persons (51 men and 127 women) with a mean age of 67.04 (range: 60-83) who was referred to the determined 25 health centres in Tehran. The anthropometric measurements were done. Further, serum 25-hydroxy vitamin D (25(OH)D), parathormone (PTH), high-sensitivity C-reactive protein (hs-CRP), osteocalcin and urine C-terminal telopeptide I (CTX-I) were collected. The mean of body mass index (P<.001), body weight (P=.002), body fat (P<.001), waist circumference (P<.001), hip circumference (P<.001), urine CTX-I concentration (P=.011), 25(OH)D (P=.030), was higher in the highest BAI category in comparison with the lowest one. BAI was negatively correlated with urine CTX-I concentration (r=-0.165, P=.028). Moreover, linear regression showed an inverse association between BAI with urine CTX-I (β=-0.165, P=.025) and 25(OH)D (β=-0.039, P=.029). Moreover, the percentage of body fat was positively associated with serum hs-CRP (β=0.026, P=.002). Our study showed a significant inverse association between BAI with urinary CTX-I which shows the effect of obesity on bone health. This study suggests that more clinical and prospective studies for monitoring body fat may have some favourable impacts on bone health.

Intra‐articular Injection of Baicalein Inhibits Cartilage Catabolism and NLRP3 Inflammasome Signaling in a Posttraumatic OA Model

Baicalein has been shown to have chondroprotective potential in vitro. However, its effect on disease modification in osteoarthritis (OA) is largely unknown. The present study is aimed at determining whether baicalein could slow the progression of OA and inhibit OA-related inflammation in a rat model of destabilization of the medial meniscus (DMM) and the underlying mechanisms. The rats subjected to DMM surgery were treated with baicalein (0.8, 1.6, and 3.2 μg/L, 50 μL, once a week) by intra-articular injection for 6 weeks. Dexamethasone (0.4 mg/mL, 50 μL, once a week) was used as a positive control. Histologic grading of cartilage degeneration was performed using the Osteoarthritis Research Society International (OARSI) recommended grading system (on a scale of 0-6). The expression levels of molecules associated with cartilage homeostasis and inflammatory cytokines were analyzed; moreover, the NLRP3 inflammasome activation and cartilage oxidative stress-associated molecules were determined. Baicalein treatment reduced the OARSI score and slowed OA disease progression in a dose-dependent manner within a certain range. Compared with DMM rats, intra-articular injection of baicalein led to (1) reduced levels of inflammatory mediates such as IL-1β and TNF-α, (2) reduced immunochemical staining of MMP-13 and ADAMTS-5, (3) suppressed immunochemical staining loss of type II collagen, (4) reduced expression of cartilage degradation markers including CTX-II and COMP in urine, and (5) inhibited NLRP3 inflammasome activation rather than regulated expression of SOD, GSH, and MDA. In contrast to the administration of baicalein, dexamethasone injection showed similar effects to slow OA progression, while dexamethasone inhibited NLRP3 inflammasome partly through decreasing levels of SOD, GSH, and MDA. This study indicated that baicalein may have the potential for OA prevention and exerts anti-inflammatory effects partly via suppressing NLRP3 inflammasome activation without affecting oxidative stress-associated molecules, and inhibition of cartilage catabolism enzymes in an OA rat model.

Multivariable logistic and linear regression models for identification of clinically useful biomarkers for osteoarthritis

Osteoarthritis (OA) is the most common chronic degenerative joint disease which causes substantial joint pain, deformity and loss of activities of daily living. Currently, there are over 500 million OA cases worldwide, and there is an urgent need to identify biomarkers for early detection, and monitoring disease progression in patients without obvious radiographic damage to the joint. We have used regression modelling to describe the association of 19 of the currently available biomarkers (predictors) with key radiographic and clinical features of OA (outcomes) in one of the largest and best characterised OA cohort (NIH Osteoarthritis Initiative). We demonstrate that of the 19 currently available biomarkers only 4 (serum Coll2-1 NO2, CS846, COMP and urinary CTXII) were consistently associated with established radiographic and/or clinical features of OA. These biomarkers are independent of one another and provide additional predictive power over, and above established predictors of OA such as age, gender, BMI and race. We also show that that urinary CTXII had the strongest and consistent associations with clinical symptoms of OA as well as radiographic evidence of joint damage. Accordingly, urinary CTXII may aid in early diagnosis of OA in symptomatic patients without radiographic evidence of OA.

Double-blind trial of solid lipid Boswellia serrata particles (SLBSP) vs. standardized Boswellia serrata gum extract (BSE) for osteoarthritis of knee.

Objectives The present study was planned to investigate the efficacy of SLBSP vs. standardized BSE for symptomatic knee osteoarthritis (OA) treatment. Methods It was a prospective, randomized, double-blind, double-dummy, placebo-controlled, and single-centre clinical trial for symptomatic osteoarthritis of knee. Subjects were randomized toreceive SLBSP capsule+BSE Placebo or BSE tablet+SLBSP placebo for two months. Patients were allowed to take rescue analgesics (Acelofenac 100mg). Improvement in pain and function was assessed utilizing WOMAC, VAS. Level of CTX-II in urine and serum levels of inflammatory cytokines including IL-2, IL-4, IL-6, TNF-α, and IFN-γ was measured initially and at end of treatment. Results and conclusions Western Ontario and McMaster Universities osteoarthritis index (WOMAC) and Visual Analog Scale score improved markedly in SLBSP as well as in BSE arm (p<0.05). Difference in VAS and WOMAC scores between the two arms was not statistically significant. Most significant effect was observed in the need for rescue analgesics. SLBSP caused marked lowering of pro-inflammatory cytokines levels whereas a several fold increase was noted in the BSE arm (p<0.05). Both groups showed marked improvement in pain, SLBSP being superior to BSE with respect to reducing the need for rescue analgesics in addition to modulating inflammatory cytokines.

Serological CTX-II does not measure the same as urinary CTX-II

Type II collagen is the most abundant protein of articular cartilage. The urinary cross-linked C-terminal telopeptide of type II collagen (uCTX-II) is a matrix metalloproteinase (MMP) cleaved fragment and may be the most well-validated biomarker in osteoarthritis. The aim was to develop a serological immunoassay of CTX-II (sCTX-II) and evaluated both sCTX-II and uCTX-II levels in a cross-sectional osteoarthritis cohort. The biological relevance of sCTX-II was validated in bovine cartilage explants cultured in the presence of Oncostatin M and tumor necrosis factor alpha (OT) or OT supplemented with GM6001 for 3 weeks. Serum and urine samples from an osteoarthritis cohort were assayed using sCTX-II and uCTX-II, respectively. Spearman's correlation was performed to evaluate the correlation between sCTX-II and uCTX-II. The association between the level of biomarkers and clinical variables was also investigated. The supernatant analyzed in sCTX-II showed significant higher CTX-II levels in the end phases of explant culture compared to the vehicle group. The release of CTX-II was completely suppressed by GM6001. The sCTX-II levels in serum were not associated with uCTX-II in urine although sCTX-II levels in urine were significantly correlated with uCTX-II. uCTX-II correlated with age and gender while sCTX-II did not. sCTX-II cannot demonstrate any clinical relevance in a cross-sectional OA cohort as uCTX-II did. The sCTX-II assay can reflect the MMP-mediated type II collagen degradation in bovine cartilage explants. However, sCTX-II and uCTX-II assays show different patterns suggesting the presence of CTX-II in blood may be different from that of urine.