ArticleRedox biology2014
Vitamin D deficiency associates with γ-tocopherol and quadriceps weakness but not inflammatory cytokines in subjects with knee osteoarthritis.
Article in Redox biology, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 21 papers, 1 of them a synthesis that pooled it.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
21 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Association Between Vitamin D and Uric Acid in Adults: A Systematic Review and Meta-Analysis.Hormone and metabolic research = Hormon- und Stoffwechselforschung = Hormones et metabolisme · 2020Pooled it
- Effect of long term vitamin D supplementation on biomarkers of inflammation in Latino and African-American subjects with pre-diabetes and hypovitaminosis D.Hormone and metabolic research = Hormon- und Stoffwechselforschung = Hormones et metabolisme · 2015Trial
- Vitamin D Status and Supplementation and the Functional Outcomes of Human Musculoskeletal Tissues: A Stratified Systematic Review.Health science reports · 2026Review
- Vitamin D and bone health: from physiological function to disease association.Nutrition & metabolism · 2025Review
- Vitamin D: A key player in COVID-19 immunity and lessons from the pandemic to combat immune-evasive variants.Inflammopharmacology · 2024Review
- Effect of serum 25-hydroxyvitamin D level on quadriceps strength: a systematic review and meta-analysis.BMC sports science, medicine & rehabilitation · 2024Article
- Current Evidence on and Clinical Implications of Vitamin D Levels in Pain and Functional Management of Knee Osteoarthritis: A Systematic Review.Clinics and practice · 2024Review
- Musculoskeletal Ultrasound in Monitoring the Efficacy of Gout: A Prospective Study Based on Tophus and Double Contour SignBalkan medical journal · 2023Article
- The association of vitamin D status with oxidative stress biomarkers and matrix metalloproteinases in patients with knee osteoarthritis.Frontiers in nutrition · 2023Article
- Association of Serum Vitamin D with Serum Cytokine Profile in Patients with Knee Osteoarthritis.Cartilage · 2021Article
- Vitamin K and D Status in Patients with Knee Osteoarthritis: An Analytical Cross-sectional Study.Mediterranean journal of rheumatology · 2021Article
- IL-33, IL-37, and Vitamin D Interaction Mediate Immunomodulation of Inflammation in Degenerating Cartilage.Antibodies (Basel, Switzerland) · 2021Article
- The Oxidative Stress in Knee Osteoarthritis Patients. An Attempt of Evaluation of Possible Compensatory Effects Occurring in the Disease Development.Medicina (Kaunas, Lithuania) · 2019Article
- The Role of Vitamin E in Preventing and Treating Osteoarthritis - A Review of the Current Evidence.Frontiers in pharmacology · 2018Review
- Damage-associated molecular patterns in the pathogenesis of osteoarthritis: potentially novel therapeutic targets.Molecular and cellular biochemistry · 2017Review
- Vitamin D Supplementation Improves Quality of Life and Physical Performance in Osteoarthritis Patients.Nutrients · 2017Article
- Which Predicts Quadriceps Muscle Strength in Knee Osteoarthritis: Biological Markers or Clinical Variables?Archives of rheumatology · 2017Article
- Vitamin D attenuates inflammation, fatty infiltration, and cartilage loss in the knee of hyperlipidemic microswine.Arthritis research & therapy · 2016Article
- Association between serum vitamin D status and health-related quality of life (HRQOL) in an older Korean population with radiographic knee osteoarthritis: data from the Korean national health and nutrition examination survey (2010-2011).Health and quality of life outcomes · 2015Article
- Role of Vitamin D in Osteoarthritis: Molecular, Cellular, and Clinical Perspectives.International journal of endocrinology · 2015Review
Corrections and comments
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Authors and funding
7 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Knee osteoarthritis (OA) is a degenerative joint condition and a leading cause of physical disability in the United States. Quadriceps weakness and inflammatory cytokines contribute to the pathogenesis of knee OA, and both of which, increase with vitamin D deficiency. Other micronutrients, such as vitamins C and E and β-carotene, modulate inflammatory cytokines and decrease during inflammation. The purpose of this study was to test the hypothesis that vitamin D deficiency associates with quadriceps weakness, an increase in serum cytokines, and a decrease in circulating micronutrients in subjects with knee OA. Subjects (age, 48±1 y; serum 25(OH)D, 25.8±1.1 ng/mL) with knee OA were categorized as vitamin D deficient (n=17; serum 25(OH)D≤20 ng/mL), insufficient (n=21; serum 25(OH)D 20-29 ng/mL), or sufficient (n=18; serum 25(OH)D≥30 ng/mL). Single-leg strength (concentric knee extension-flexion contraction cycles at 60 °/s) and blood cytokine, carotene (α and β), ascorbic acid, and tocopherol (α and γ) concentrations were measured. Quadriceps peak torque, average power, total work, and deceleration were significantly (all p<0.05) impaired with vitamin D deficiency. Serum γ-tocopherol concentrations were significantly (p<0.05) increased with vitamin D deficiency. In the vitamin D sufficient group, γ-tocopherol inversely correlated (r=-0.47, p<0.05) with TNF-α, suggesting a pro-inflammatory increase with a γ-tocopherol decrease despite a sufficient serum 25(OH)D concentration. We conclude that vitamin D deficiency is detrimental to quadriceps function, and in subjects with vitamin D sufficiency, γ-tocopherol could have an important anti-inflammatory role in a pathophysiological condition mediated by inflammation.
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