Causal Effect of Chondroitin, Glucosamine, Vitamin, and Mineral Intake on Kidney Function: A Mendelian Randomization Study.

The causal effects of chondroitin, glucosamine, and vitamin/mineral supplement intake on kidney function remain unknown, despite being commonly used. We conducted a two-sample summary-level Mendelian randomization (MR) analysis to test for causal associations between regular dietary supplement intake and kidney function. Genetic instruments for chondroitin, glucosamine, and vitamin/mineral supplement intake were obtained from a genome-wide association study of European ancestry. Summary statistics for the log-transformed estimated glomerular filtration rate (log-eGFR) were provided by the CKDGen consortium. The multiplicative random-effects inverse-variance weighted method showed that genetically predicted chondroitin and glucosamine intake was causally associated with a lower eGFR (chondroitin, eGFR change beta = -0.113%, standard error (SE) = 0.03%, p-value = 2 × 10-4; glucosamine, eGFR change beta = -0.240%, SE = 0.035%, p-value = 6 × 10-12). However, a genetically predicted vitamin/mineral supplement intake was associated with a higher eGFR (eGFR change beta = 1.426%, SE = 0.136%, p-value = 1 × 10-25). Validation analyses and pleiotropy-robust MR results for chondroitin and vitamin/mineral supplement intake supported the main results. Our MR study suggests a potential causal effect of chondroitin and glucosamine intake on kidney function. Therefore, clinicians should carefully monitor their long-term effects.

Chondroitin/Lactoferrin-dual functionalized pterostilbene-solid lipid nanoparticles as targeted breast cancer therapy.

Breast cancer remains the leading cause of cancer-associated mortality in women. Research investigating novel therapeutic approaches is thus crucial, including phytotherapeutics. Pterostilbene (PTS) is a phytochemical agent with promising efficacy against breast cancer. Poor solubility, low bioavailability and chemical instability are major drawbacks compromising PTS functionality. Herein, novel PTS-loaded solid lipid nanoparticles (PTS-SLNs) were fabricated using the ultrasonication technique. Dual-functionalization with lactoferrin (Lf) and chondroitin-sulfate (CS; CS/Lf/PTS-SLNs) was adopted as active-targeting approach. CS/Lf/PTS-SLNs demonstrated nanoparticle-size (223.42 ± 18.71 nm), low PDI (0.33 ± 0.017), acceptable zeta potential (-11.85 ± 0.07 mV) and controlled release (72.93 ± 2.93% after 24 h). In vitro studies on triple-negative MDA-MB-231 revealed prominent cytotoxicity of CS/Lf/PTS-SLNs (2.63-fold IC50 reduction), higher anti-migratory effect and cellular uptake relative to PTS-solution. The in vivo anti-tumor efficacy in an orthotopic cancer model verified the superiority of CS/Lf/PTS-SLNs; achieving 2.4-fold decrease in tumor growth compared to PTS-solution. On the molecular level, CS/Lf/PTS-SLNs enhanced suppression of VEGF, down-regulated cyclin D1 and upregulated caspase-3 and BAX, compared to PTS-solution. Also, immunohistochemical assay confirmed the higher anti-tumorigenic effect of CS/Lf/PTS-SLNs (5.87-fold decrease in Bcl-2 expression) compared to PTS-solution. Our findings highlight CS/Lf/PTS-SLNs as a promising nanoplatform for phytotherapeutic targeted-breast cancer therapy.

Glucosamine and Chondroitin Use and Mortality Among Adults in the United States from 1999 to 2014.

Introduction: Glucosamine and chondroitin are supplements that are often, but not always, used in combination for arthritis and joint pain. Multiple studies have suggested that glucosamine and chondroitin may be associated with reduced risk of several diseases, as well as all-cause, cancer- and respiratory disease-specific mortality. Methods: Nationally representative data from the National Health and Nutrition Examination Survey (NHANES) were used to further evaluate the association between glucosamine and chondroitin with mortality. Participants include 38,021 adults, ages 20+ years and older, who completed the detailed NHANES between 1999 and 2014. Participants were followed for death through linkage with the National Death Index through the end of 2015, over which time 4905 deaths occurred. Adjusted hazard ratios (HRs) for overall and cause-specific mortality were estimated using Cox regression models. Results: Despite glucosamine and chondroitin use appearing to be inversely associated with mortality in the minimally adjusted models, no association was observed in multivariable models (glucosamine: HR = 1.02; 95% confidence interval [CI]: 0.86-1.21, chondroitin: HR = 1.04, 95% CI: 0.87-1.25). No association with cancer mortality or other mortality rate was observed after multivariable adjustment. There was a suggestive, nonsignificant inverse association for cardiovascular-specific mortality (glucosamine HR = 0.72; 95% CI: 0.46-1.15, chondroitin: HR = 0.76; 95% CI: 0.47-1.21). Conclusion: The lack of significant relationship between glucosamine and chondroitin use and all-cause or cause-specific mortality after adjusting extensively for multiple covariates in this nationally representative adult population was in contrast to prior literature. Given the limited power to explore the cause-specific mortality, future well-powered studies will be needed to better understand the potential association with cardiovascular-specific mortality.

A 2022 Systematic Review and Meta-Analysis of Enriched Therapeutic Diets and Nutraceuticals in Canine and Feline Osteoarthritis.

With osteoarthritis being the most common degenerative disease in pet animals, a very broad panel of natural health products is available on the market for its management. The aim of this systematic review and meta-analysis, registered on PROSPERO (CRD42021279368), was to test for the evidence of clinical analgesia efficacy of fortified foods and nutraceuticals administered in dogs and cats affected by osteoarthritis. In four electronic bibliographic databases, 1578 publications were retrieved plus 20 additional publications from internal sources. Fifty-seven articles were included, comprising 72 trials divided into nine different categories of natural health compound. The efficacy assessment, associated to the level of quality of each trial, presented an evident clinical analgesic efficacy for omega-3-enriched diets, omega-3 supplements and cannabidiol (to a lesser degree). Our analyses showed a weak efficacy of collagen and a very marked non-effect of chondroitin-glucosamine nutraceuticals, which leads us to recommend that the latter products should no longer be recommended for pain management in canine and feline osteoarthritis.

[A multicenter cross-sectional study of quality of life and nonsurgical treatment in patients with knee osteoarthritis].

Objective: To explore the influencing factors of health-related quality of life (HRQoL) in patients with knee osteoarthritis, and to analyze the non-surgical treatment of knee osteoarthritis. Methods: Demographic variables, treatment modalities, imaging data, and 12-item short form health survey (SF-12) scores of patients with knee osteoarthritis in orthopedic outpatient departments of five hospitals in Beijing from December 2017 to November 2018 were collected to analyze influencing factors of HRQoL and non-surgical treatment. Results: A total of 2 034 patients were included. There were 530 males (26.1%) and 1 504 females (73.9%), with a mean age of (59.17±10.22) years. In terms of physical quality of life, female patients with knee osteoarthritis had lower physical components summary (PCS) compared with male patients (ß=-0.521, P=0.036); patients aged ≥64 years had lower PCS than those aged<55 years (ß=-0.636, P=0.026). Patients with an education of more than 12 years had higher PCS than those with less than 10 years (ß=1.063, P<0.001). Compared to patients with mild clinical symptoms, the PCS of patients with moderate clinical symptoms was lower (ß=-0.860, P=0.002), while the PCS of those with severe clinical symptoms was much lower (ß=-1.126, P<0.001). Patients treated with combination therapy had higher PCS than untreated patients (ß=0.731, P=0.005). In terms of mental quality of life, compared to patients engaged in sedentary work, the mental components summary (MCS) of patients engaged in mild manual labor jobs was lower (ß=-0.712, P=0.015); Compared to patients with a Charson comorbidity index of 0, patients with a Charlson comorbidity index ≥ 2 had lower MCS (ß=-1.183, P=0.007). In the past 12 months, 648 (31.9%), 143 (7.0%), 406 (20.0%), 680 (33.4%), 343 (16.9%), 681 (33.5%), 170 (8.4%) patients had used non-steroid anti-inflammatory drugs (NSAIDs), acetaminophen, glucosamine/chondroitin formulations, physical therapy, articular cavity puncture injection, traditional Chinese medicine treatment and exercise therapy, respectively. Total of 451 patients (22.2%) received monotherapy and 889 patients (43.7%) received combination therapy. Conclusions: The major non-surgical treatment methods for patients with knee osteoarthritis in Beijing are NSAIDs, physiotherapy and traditional Chinese medicine. Combination therapy is used more frequently than monotherapy. Physical quality of life is related to gender, age, education, severity of symptoms and treatment, while mental quality of life is related to occupational labor and comorbidities.

Liquid combination of hyaluronan, glucosamine, and chondroitin as a dietary supplement for knee osteoarthritis patients with moderate knee pain: A randomized controlled study.

BACKGROUND: Hyaluronan (HA), glucosamine, and chondroitin sulfate are widely consumed as dietary supplements for the treatment of knee osteoarthritis (OA). This study aimed to explore the efficacy and safety of a dietary liquid supplement mixture containing HA, glucosamine, and chondroitin in patients with knee OA who had moderate knee pain (visual analogue scale of 4-6 points). METHODS: This was a short-term, randomized, double-blind, placebo-controlled study. Subjects were allocated to administer either a bottle of 20 mL supplement mixture (50 mg HA plus 750 mg glucosamine plus 250 mg chondroitin, namely A + HA) or placebo once daily for 8 weeks. Outcome measures included the Knee Injury and Osteoarthritis Outcome Score, Western Ontario and McMaster Universities Osteoarthritis Index, 36-item Short Form Survey (SF-36), Chinese version of Pittsburgh Sleep Quality Index, and incidence of adverse event were evaluated at the end of week 8. Efficacy analyses were conducted in the modified intent-to-treat population. RESULTS: Of the 80 subjects in the modified intent-to-treat population, 39 received A + HA while 41 received placebo. After 8 weeks of treatment, the A + HA group failed to demonstrate a significant symptomatic efficacy and quality of life improvement in terms of Knee Injury and Osteoarthritis Outcome Score, Western Ontario and McMaster Universities Osteoarthritis Index, SF-36, and Chinese version of Pittsburgh Sleep Quality Index as compared to the placebo group. However, the mean changes in most of the SF-36 scale scores were numerically higher in the A + HA group than in the placebo group. No treatment-related adverse event was reported in both groups. CONCLUSIONS: This present study found that the combination of liquid low molecular weight HA, glucosamine, and chondroitin oral supplement did not effectively improve knee OA pain and symptoms after short-term use in knee OA patients with moderate knee pain. However, these results should be interpreted with caution due to the intrinsic limitation of the study design.

The effect of oral low molecular weight liquid hyaluronic acid combination with glucosamine and chondroitin on knee osteoarthritis patients with mild knee pain: An 8-week randomized double-blind placebo-controlled trial.

BACKGROUND: The popularity of dietary supplements for knee osteoarthritis (OA) management is on the rise; however, their effects are still debated. METHODS: This study aimed to investigate the effect of an oral low molecular weight liquid hyaluronic acid supplement in the treatment of knee OA patients with mild knee pain (visual analogue scale [VAS] ≤ 3) in Taiwan population. This was a randomized, double-blind, placebo-controlled study. Forty-seven subjects were enrolled and randomly allocated to either the A+HA or the placebo groups. The subjects were required to drink a bottle contained 20 mL of A+HA or placebo daily throughout an 8-week study period. The efficacy was assessed by using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the 36-item Short Form Survey (SF-36). RESULTS: At Week 8, significant reductions from baseline in the WOMAC pain (-2.6 ±â€Š1.68, P < .0001), stiffness (-1.2 ±â€Š1.50, P = .007), physical function (-5.8 ±â€Š4.39, P < .0001), and total (-9.4 ±â€Š5.82, P < .0001) scores were observed in the A+HA group but not in the placebo group. Significant differences in the mean change of WOMAC scores from baseline at Week 8 between groups were detected (P < .01). At Week 8, the A+HA group also showed significant improvements in SF-36 physical functioning (2.7 ±â€Š3.10, P = .001) and bodily pain (0.7 ±â€Š1.50, P < .05) domains. Although the A+HA group had a higher increase in the SF-36 total score than the placebo group but the difference was not statistically significant (2.1 ±â€Š12.75 vs 0.3 ±â€Š19.66, P = .12). CONCLUSIONS: Oral administration of low molecular weight liquid HA appeared to be effective for knee OA patients with mild knee pain (VAS ≤ 3) in the relief of knee OA symptoms, particularly in pain and physical function.Clinical Trial Registration: NCT04352322.

Characterization of individuals with osteoarthritis in the United States and their use of prescription and over-the-counter supplements.

PURPOSE: Osteoarthritis (OA) is a frequently occurring, chronic condition; however, few studies describe the clinical characteristics of individuals with OA and the treatments they use to manage their symptoms. We conducted a study to characterize the OA population in the US and describe the nonsurgical management used by this population based on consumer research data collected through an online survey. METHODS: Data from the 2017 US National Health and Wellness Survey (NHWS) for adults aged ≥35 years were used to evaluate the relationship between OA and certain study participant characteristics and to identify the most commonly used treatment options. NHWS data were collected through a survey of individuals drawn from the internet panel maintained by Lightspeed Research (Bridgewater, New Jersey) and its panel partners. Weighted estimates were generated using data from the 2016 Current Population Survey (Annual Demographics File) of the US Census Bureau. Comparisons between the general and OA populations were made based on body mass index (BMI), exercise frequency, and comorbid diagnoses of hypertension or diabetes. Among the OA population, the use of dietary supplements, prescription or over-the-counter (OTC) treatments with chondroitin with or without glucosamine (Ch ± Gl), prescription treatment by time since OA diagnosis, and utilization of a physical therapist were also recorded. RESULTS: The prevalence of OA in the overall population was 17.6 % and was higher for individuals with a BMI ≥ 25 (21.9 %), patients diagnosed with hypertension or diabetes (36.2 %), and those who did not exercise regularly (19.0 %). Adults without OA were more likely to exercise regularly (12 days per month or more) than adults diagnosed with OA. Ch ± Gl (6.0 %) was the most commonly used OTC dietary supplement in the OA population, followed by omega-3 fatty acids (2.8 %), vitamin D (1.9 %), calcium (1.1 %), and multivitamins (0.7 %). Individuals using Ch ± Gl were more likely to use OTC only products (75.4 % vs 37.3 %) or prescription medications, namely non-steroidal anti-inflammatory drugs (NSAIDs) and/or opioids, and OTC products (24.6 % vs 13.0 %) compared with individuals not using Ch ± Gl, while individuals not using Ch ± Gl were more likely to be untreated (30.3 % vs 0) or to use prescription medications only (19.4 % vs 0). Nearly 32 % of individuals with OA reported using prescription treatments, and the likelihood of using a prescription treatment increased with number of years since OA diagnosis (<3 years: 27.5 %; ≥21 years: 32.5 %). The pharmaceutical products used by this population primarily consisted of nonsteroidal anti-inflammatory drugs, acetaminophen and opioids. Approximately 13 % of patients with OA had visited a physical therapist in the past 6 months. CONCLUSIONS: The prevalence of OA was higher in those with a high BMI, and comorbid diabetes or hypertension. Individuals with OA using Ch ± Gl primarily reported use of OTC products only or used them in combination with prescription products. The likelihood of using prescription products increased with the length of OA history. These data provide valuable new information about demographics, clinical characteristics, and commonly used prescription and OTC treatments and dietary supplements in the OA population.

Glucosamine and Chondroitin Use in Relation to C-Reactive Protein Concentration: Results by Supplement Form, Formulation, and Dose.

Objectives: Glucosamine and chondroitin supplements have been associated with reduced inflammation, as measured by C-reactive protein (CRP). It is unclear if associations vary by formulation (glucosamine alone vs. glucosamine+chondroitin), form (glucosamine hydrochloride vs. glucosamine sulfate), or dose. Design, Subjects, Setting, Location: The authors evaluated these questions using cross-sectional data collected between 1999 and 2010 on 21,917 US adults, surveyed as part of the National Health and Nutrition Examination Survey (NHANES). Exposures: Glucosamine and chondroitin use was assessed during an in-home interview; exposures include supplement formulation, form, and dose. Outcome/Analysis: CRP was measured using blood collected at interview. Survey-weighted linear regression was used to evaluate the multivariable-adjusted association between exposures and log-transformed CRP. Results: In early years (1999-2004), use of glucosamine (ratio = 0.87; 95% confidence interval [CI] = 0.79-0.96) and chondroitin (ratio = 0.83; 95% CI = 0.72-0.95) was associated with reduced CRP. However, associations significantly varied by calendar time (p-interaction = 0.04 and p-interaction = 0.01, respectively), with associations nonsignificant in later years (ratio = 1.09; 95% CI = 0.94-1.28 and ratio = 1.16; 95% CI = 0.99-1.35, respectively). Consequently, all analyses have been stratified by calendar time. Associations did not significantly differ by formulation in either set of years; however, significant associations were observed for combined use of glucosamine+chondroitin (ratioearly = 0.82; 95% CI = 0.72-0.95; ratiolate = 1.16; 1.00-1.35), but not glucosamine alone. Associations also did not significantly differ by supplement form. Even so, a significant inverse association was observed only for glucosamine sulfate in the early years (ratio = 0.78; 95% CI = 0.64-0.95); no significant association was observed for glucosamine hydrochloride. No significant trends were observed by dose. Conclusions: Although a significant inverse association was observed for glucosamine and chondroitin and CRP in early years, this association did not hold in later years. This pattern held for combined use of glucosamine+chondroitin as well as glucosamine sulfate, although associations did not significantly vary by supplement form, formulation, or dose. Further study is needed to better understand these associations in the context of calendar time.

Must-Read Family Medicine Research-Glucosamine/Chondroitin Supplements and Mortality, Telomere Length and the Doctor-Patient Relationship, Reducing Opioid Use, and More.

This issue of the Journal contains some exceptional research articles. A few are truly "must-reads," including a fascinating look at the relationship between having a usual source of care and telomere length. Glucosamine/chrondroitin supplementation seems to be helpful for more than just arthritis pain. There is a very practical advice on keeping patients discharged from the emergency department out of the hospital and on reducing patient requests for inappropriate antibiotics. This issue also features 5 articles addressing how family physicians can combat the opioid epidemic. Three articles highlight research on diabetes and another 3 on breast cancer. Payment reform, dermoscopy, and telemedicine are among many other topics covered.

Glucosamine and Chondroitin Supplements and Risk of Colorectal Adenoma and Serrated Polyp.

BACKGROUND: Studies have shown an inverse association between use of glucosamine and chondroitin supplements and colorectal cancer risk. However, the association with the precursor lesion, colorectal adenoma and serrated polyp, has not been examined. METHODS: Analyses include 43,163 persons from the Nurses' Health Study (NHS), Health Professionals Follow-up Study (HPFS), and NHS2 who reported on glucosamine/chondroitin use in 2002 and who subsequently underwent ≥1 lower gastrointestinal endoscopy. By 2012, 5,715 conventional (2,016 high-risk) adenomas were detected, as were 4,954 serrated polyps. Multivariable logistic regression for clustered data was used to calculate OR and 95% confidence intervals (CI). RESULTS: Glucosamine/chondroitin use was inversely associated with high risk and any conventional adenoma in NHS and HPFS: in the pooled multivariable-adjusted model, glucosamine + chondroitin use at baseline was associated with a 26% (OR = 0.74; 95% CI, 0.60-0.90; P heterogeneity = 0.23) and a 10% (OR = 0.90; 95% CI, 0.81-0.99; P heterogeneity = 0.36) lower risk of high-risk adenoma and overall conventional adenoma, respectively. However, no association was observed in NHS2, a study of younger women (high-risk adenoma: OR = 1.09; 95% CI, 0.82-1.45; overall conventional adenoma: OR = 1.00; 95% CI, 0.86-1.17), and effect estimates pooled across all three studies were not significant (high-risk: OR = 0.83; 95% CI, 0.63-1.10; P heterogeneity = 0.03; overall conventional adenoma: OR = 0.93; 95% CI, 0.85-1.02; P heterogeneity = 0.31). No associations were observed for serrated polyps. CONCLUSIONS: Glucosamine/chondroitin use was associated with lower risks of high-risk and overall conventional adenoma in older adults; however, this association did not hold in younger women, or for serrated polyps. IMPACT: Our study suggests that glucosamine and chondroitin may act on early colorectal carcinogenesis in older adults.

The effectiveness of treatments for Kashin-Beck disease: a systematic review and network meta-analysis.

OBJECTIVES: This study aims to evaluate the efficacy of treatments for Kashin-Beck disease (KBD). METHOD: We searched PubMed, Cochrane Central Register of Controlled Trials, Embase, Web of Science, SinoMed, Chinese National Knowledge Infrastructure, reference lists and published systematic reviews and registries of ongoing trials through May 2015 for randomised controlled trials (RCTs) of treatments for KBD. Outcomes of interest were pain, function, stiffness, overall clinical improvement, radiographic improvement (X-ray) and adverse events. Frequentist network meta-analyses were conducted using random-effects consistency model to assess the efficacy of treatments for KBD. RESULTS: Forty-four RCTs with 9815 participants were included in the review. In children or adolescents, selenium (risk ratio 1.88, 95% confidence interval (CI) 1.51-2.33), vitamin C (2.03, 1.40-2.95) and aspirin (2.14, 1.12-4.08) were effective for radiographic structure improvement. In adults, chondroitin plus glucosamine was the best for pain (standardised mean difference 1.46, 95% CI 1.07-1.85), followed by intra-articular injection of hyaluronic acid (IAH) (1.09, 0.70-1.48), chondroitin (0.84, 0.47-1.21), diclofenac (0.63, 1.18-1.08), naproxen (0.55, 0.12-0.98), meloxicam (0.52, 0.03-1.01) and glucosamine (0.40, 0.13-0.67) compared to placebo, with similar results for other clinical outcomes in adults. However, the strength of most evidence was limited by the small number of trials with low to moderate quality. CONCLUSIONS: Selenium supplement has demonstrated some benefits for structural improvement of the disease in children. Chondroitin, glucosamine, IAH and nonsteroid anti-inflammatory drugs are effective for symptom improvements of KBD in adults. Evidence of surgical and complementary treatments for symptoms and aspirin and vitamin C for structure has yet to be established.Key Points• There were 23 nutraceuticals, pharmaceuticals and surgical and complementary treatments assessed for Kashin-Beck disease (KBD) in randomised trials.• Among the 23 treatments, chondroitin, glucosamine, IAH and non-steroid anti-inflammatory drugs are more effective than placebo to relieve symptoms for adults with KBD.• Selenium supplement is more effective than placebo for radiographic improvement in children or adolescents.• The efficacy of surgeries, aspirin, vitamin C and complementary treatments for KBD has not been established yet.

Effectiveness of Cucumis sativus extract versus glucosamine-chondroitin in the management of moderate osteoarthritis: a randomized controlled trial.

PURPOSE: Osteoarthritis (OA) is an age-related disease caused by the wear and tear of the joints. Presently, there is no known cure for OA, but its management involves the use of high doses of pain killers and antiinflammatory agents with different side and dependency effects. Alternative management strategies involve the use of high doses of glucosamine-chondroitin (GC). This study was carried out to evaluate the efficacy of Q-Actin™, an aqueous extract of Cucumis sativus (cucumber; CSE) against GC in the management of moderate knee OA. PATIENTS AND METHODS: Overall, 122 patients (56 males and 66 females) aged between 40 and 75 years and diagnosed with moderate knee OA were included in this randomized double-blind, parallel-group clinical trial that took place in three different centers. The 180 day intervention involved two groups of 61 participants in each: the GC group, which received orally the generally prescribed dose of 1,350 mg of GC twice daily and the CSE group, which received orally10 mg twice daily of CSE. The Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), Visual Analog scale, and Lequesne's Functional Index were used to evaluate pain, stiffness, and physical function of knee OA in participants at baseline (Day 0) and on Days 30, 60, 90, 120, 150, and 180. RESULTS: In the CSE group, the WOMAC score was decreased by 22.44% and 70.29% on Days 30 and 180, respectively, compared to a 14.80% and 32.81% decrease in the GC group. Similar trends were observed for all the other pain scores. No adverse effect was reported during the trial period. CONCLUSION: The use of 10 mg CSE, twice daily, was effective in reducing pain related to moderate knee OA and can be potentially used in the management of knee pain, stiffness, and physical functions related to OA.

Natural Products for Promoting Joint Health and Managing Osteoarthritis.

PURPOSE OF REVIEW: Osteoarthritis, the most common joint disease, is associated with substantial medical costs, lost productivity, and reduced quality of life. However, available pharmaceutical treatments have limitations in terms of efficacy and long-term safety. RECENT FINDINGS: In vitro evidence suggests that some natural products may possess anti-inflammatory and anti-oxidative properties and may inhibit the release of key osteoarthritis-related cytokines. There is, therefore, ongoing interest in identifying natural products that safely promote joint health and treat osteoarthritis. Numerous plant extracts, including curcumin, Boswellia extract, and pycnogenol, have shown effect sizes (ES) for reducing pain and functional disability larger than those observed with analgesics and products such as glucosamine and chondroitin. The ES for methylsulfonylmethane and avocado/soybean unsaponifiables are also considered to be clinically relevant. Data from a small number of studies using natural products for treating osteoarthritis are promising but require confirmation in further well-designed clinical trials.

Cytochrome P450 2C9-natural antiarthritic interactions: Evaluation of inhibition magnitude and prediction from in vitro data.

Many dietary supplements are promoted to patients with osteoarthritis (OA) including the three naturally derived compounds, glucosamine, chondroitin and diacerein. Despite their wide spread use, research on interaction of these antiarthritic compounds with human hepatic cytochrome P450 (CYP) enzymes is limited. This study aimed to examine the modulatory effects of these compounds on CYP2C9, a major CYP isoform, using in vitro biochemical assay and in silico models. Utilizing valsartan hydroxylase assay as probe, all forms of glucosamine and chondroitin exhibited IC50 values beyond 1000 µM, indicating very weak potential in inhibiting CYP2C9. In silico docking postulated no interaction with CYP2C9 for chondroitin and weak bonding for glucosamine. On the other hand, diacerein exhibited mixed-type inhibition with IC50 value of 32.23 µM and Ki value of 30.80 µM, indicating moderately weak inhibition. Diacerein's main metabolite, rhein, demonstrated the same mode of inhibition as diacerein but stronger potency, with IC50 of 6.08 µM and Ki of 1.16 µM. The docking of both compounds acquired lower CDOCKER interaction energy values, with interactions dominated by hydrogen and hydrophobic bondings. The ranking with respect to inhibition potency for the investigated compounds was generally the same in both in vitro enzyme assay and in silico modeling with order of potency being diacerein/rhein > various glucosamine/chondroitin forms. In vitro-in vivo extrapolation of inhibition kinetics (using 1 + [I]/Ki ratio) demonstrated negligible potential of diacerein to cause interaction in vivo, whereas rhein was predicted to cause in vivo interaction, suggesting potential interaction risk with the CYP2C9 drug substrates.

Effects of cytotoxic cis- and trans-diammine monochlorido platinum(II) complexes on selenium-dependent redox enzymes and DNA.

Here we present the preparation of 14 pairs of cis- and trans-diammine monochlorido platinum(II) complexes, coordinated to heterocycles (i.e., imidazole, 2-methylimidazole and pyrazole) and linked to various acylhydrazones, which were designed as potential inhibitors of the selenium-dependent enzymes glutathione peroxidase 1 (GPx-1) and thioredoxin reductase 1 (TrxR-1). However, no inhibition of bovine GPx-1 and only weak inhibition of murine TrxR-1 was observed in in vitro assays. Nonetheless, the cis configured diammine monochlorido Pt(II) complexes exhibited cytotoxic and apoptotic properties on various human cancer cell lines, whereas the trans configured complexes generally showed weaker potency with a few exceptions. On the other hand, the trans complexes were generally more likely to lack cross-resistance to cisplatin than the cis analogues. Platinum was found bound to the nuclear DNA of cancer cells treated with representative Pt complexes, suggesting that DNA might be a possible target. Thus, detailed in vitro binding experiments with DNA were conducted. Interactions of the compounds with calf thymus DNA were investigated, including Pt binding kinetics, circular dichroism (CD) spectral changes, changes in DNA melting temperatures, unwinding of supercoiled plasmids and ethidium bromide displacement in DNA. The CD results indicate that the most active cis configured pyrazole-derived complex causes unique structural changes in the DNA compared to the other complexes as well as to those caused by cisplatin, suggesting a denaturation of the DNA structure. This may be important for the antiproliferative activity of this compound in the cancer cells.

Outpatient management of knee osteoarthritis.

Osteoarthritis of the knee is a common disease that causes significant disability. Most patients can be managed conservatively in the outpatient setting. A small minority require surgery. The cornerstones of treatment are weight loss, exercise and analgesia. Walking aids, medial patellar taping, acupuncture and transcutaneous electrical nerve stimulation are useful management adjuncts. Current evidence does not support routine prescription of glucosamine and chondroitin supplements. Early consultation with an orthopaedic surgeon should be made when conservative measures fail.

New insight into chondroitin and heparosan-like capsular polysaccharide synthesis by profiling of the nucleotide sugar precursors.

Escherichia coli K4 and K5 capsular polysaccharides (K4 and K5 CPSs) have been used as starting material for the biotechnological production of chondroitin sulfate (CS) and heparin (HP) respectively. The CPS covers the outer cell wall but in late exponential or stationary growth phase it is released in the surrounding medium. The released CPS concentration was used, so far, as the only marker to connect the strain production ability to the different cultivation conditions employed. Determining also the intracellular UDP-sugar precursor concentration variations, during the bacterial growth, and correlating it with the total CPS production (as sum of the inner and the released ones), could help to better understand the chain biosynthetic mechanism and its bottlenecks. In the present study, for the first time, a new capillary electrophoresis method was set up to simultaneously analyse the UDP-glucose (UDP-Glc), UDP-galactose (UDP-Gal), UDP-N-acetylgalactosamine (UDP-GalNAc), UDP-N-acetylglucosamine (UDP-GlcNAc) and UDP-glucuronic acid (UDP-GlcA) and the inner CPS portion, extracted at the same time from the bacterial biomasses; separation was performed at 18°C and 18 kV with a borate-based buffer and detection at 200 nm. The E. coli K4 and K5 UDP-sugar pools were profiled, for the first time, at different time points of shake flask growths on a glycerol-containing medium and on the same medium supplemented with the monosaccharide precursors of the CPSs: their concentrations varied from 0.25 to 11 µM·gcdw-1, according to strain, the type of precursor, the growth phase and the cultivation conditions and their availability dramatically influenced the total CPS produced.

Use of glucosamine and chondroitin supplements in relation to risk of colorectal cancer: Results from the Nurses' Health Study and Health Professionals follow-up study.

Recent epidemiologic evidence has emerged to suggest that use of glucosamine and chondroitin supplements may be associated with reduced risk of colorectal cancer (CRC). We therefore evaluated the association between use of these non-vitamin, non-mineral supplements and risk of CRC in two prospective cohorts, the Nurses' Health Study and Health Professionals Follow-up Study. Regular use of glucosamine and chondroitin was first assessed in 2002 and participants were followed until 2010, over which time 672 CRC cases occurred. Cox proportional hazards regression was used to estimate relative risks (RRs) within each cohort, and results were pooled using a random effects meta-analysis. Associations were comparable across cohorts, with a RR of 0.79 (95% CI: 0.63-1.00) observed for any use of glucosamine and a RR of 0.77 (95% CI: 0.59-1.01) observed for any use of chondroitin. Use of glucosamine in the absence of chondroitin was not associated with risk of CRC, whereas use of glucosamine + chondroitin was significantly associated with risk (RR: 0.77; 95% CI: 0.58-0.999). The association between use of glucosamine + chondroitin and risk of CRC did not change markedly when accounting for change in exposure status over follow-up (RR: 0.75; 95% CI: 0.58-0.96), nor did the association significantly vary by sex, aspirin use, body mass index, or physical activity. The association was comparable for cancers of the colon and rectum. Results support a protective association between use of glucosamine and chondroitin and risk of CRC. Further study is needed to better understand the chemopreventive potential of these supplements.