Relationships between Vitamin D and Selected Cytokines and Hemogram Parameters in Professional Football Players-Pilot Study

Impact of Reduced Vitamin D Levels on Pain, Function, and Severity in Knee or Hip Osteoarthritis

BACKGROUND

Vitamin D is beneficial for musculoskeletal health. Although low levels of vitamin D are linked to increased pain in knee osteoarthritis (OA), their association with functionality remains understudied.

OBJECTIVE

This study aimed to investigate the association between vitamin D deficiency and functional status in elderly individuals with OA and explore the potential correlation between vitamin D deficiency and plasma levels of tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6).

METHODS

The study included older adults (≥60 years) from an ageing study, encompassing 105 OA patients and 152 controls. OA diagnosis was confirmed radiographically, and the WOMAC questionnaire assessed functional impairment in these patients. Blood samples were collected to measure 25(OH) vitamin D levels by chemiluminescence and TNF-α and IL-6 levels by ELISA.

RESULTS

Patients with vitamin D insufficiency/deficiency exhibited more severe cases of OA compared to those with normal vitamin D levels (p = 0.04). Vitamin D levels were inversely correlated with functional impairment in OA, according to the WOMAC Index (global: rS = -0.25, p = 0.01; pain: rS = -0.21, p = 0.03). Moreover, OA patients with vitamin D deficiency showed significantly higher levels of TNF-α and IL-6 (p < 0.05, Mann-Whitney test).

CONCLUSIONS

Reduced levels of vitamin D are associated with more severe cases of hip and knee osteoarthritis, increased pain, greater functional impairment, and elevated serum levels of TNF-α and IL-6. Further research is required to elucidate the mechanisms underlying the influence of vitamin D on osteoarthritis and to evaluate the potential benefits of vitamin D supplementation for mitigating disease symptoms and progression.

Vitamin D Supplementation of 7–8 Years Old Children from Different Geographical Areas (48–52° North Latitude): Cross Sectional Study

Background. The prevalence of vitamin D deficiency in children by their geographic latitude of residence requires follow-up study. This is crucial for implementation of preventive measures that can reduce the risk of developing pathological conditions associated with vitamin D deficiency.

Objective. The aim of the study is to study the vitamin D supplementation of 7–8 years old children living in different geographical latitudes of one subject of Russian Federation.

Methods. The study included relatively healthy children living in three geographical areas (northern — 52°, central — 50°, southern — 48°) of one region (Khabarovsk Krai). Vitamin D supplementation was evaluated by 25(OH)D serum concentration via enzyme-linked immunosorbent assay. Vitamin D insufficiency was diagnosed at 25(OH)D concentration of 21–30 ng/ml, deficiency — 10–20 ng/ml, severe deficiency — < 10 ng/ml; optimal 25(OH)D concentration was considered as 30–100 ng/ml.

Results. The increase in prevalence of vitamin D deficiency and insufficiency has been revealed with gradual increase from southern (57%) to central (73%) and northern (83%) geographic areas in 7–8 years old children living in the same region. The prevalence of vitamin D deficiency and insufficiency (25(OH)D ≤ 30 ng/mL) among children living in the northern geographic area was greater by 3.8-fold (95% confidence interval 1.2–12.7) then among peers living in the southern areas.

Conclusion. One factor affecting 25(OH)D serum concentration in children of this region is the insolation level determined by the geographical latitude of residence. The 4°N difference is significant in determining vitamin D status in residents of relatively high latitudes. Further studies of factors associated with 25(OH)D concentration in children living in different latitudes are required (insolation level, number of sunny days per year, food and household characteristics in families).

Factors Modulating COVID-19: A Mechanistic Understanding Based on the Adverse Outcome Pathway Framework

Addressing factors modulating COVID-19 is crucial since abundant clinical evidence shows that outcomes are markedly heterogeneous between patients. This requires identifying the factors and understanding how they mechanistically influence COVID-19. Here, we describe how eleven selected factors (age, sex, genetic factors, lipid disorders, heart failure, gut dysbiosis, diet, vitamin D deficiency, air pollution and exposure to chemicals) influence COVID-19 by applying the Adverse Outcome Pathway (AOP), which is well-established in regulatory toxicology. This framework aims to model the sequence of events leading to an adverse health outcome. Several linear AOPs depicting pathways from the binding of the virus to ACE2 up to clinical outcomes observed in COVID-19 have been developed and integrated into a network offering a unique overview of the mechanisms underlying the disease. As SARS-CoV-2 infectibility and ACE2 activity are the major starting points and inflammatory response is central in the development of COVID-19, we evaluated how those eleven intrinsic and extrinsic factors modulate those processes impacting clinical outcomes. Applying this AOP-aligned approach enables the identification of current knowledge gaps orientating for further research and allows to propose biomarkers to identify of high-risk patients. This approach also facilitates expertise synergy from different disciplines to address public health issues.

Biological, Psychological, and Physical Performance Variations in Football Players during the COVID-19 Lockdown: A Prospective Cohort Study

This prospective cohort study aimed to evaluate whether COVID-19 lockdown caused biological, psychological, and/or physical performance variations in footballers. We compared the 2018/2019 and 2019/2020 seasons evaluating the plasma volume, hematological parameters, iron/ferritin, creatine kinase, vitamin D, cortisol, testosterone, and physiological state of players of the Italian football major league (Serie A). Measurements were performed before the preparatory period (T0), at the beginning (T1) and in the middle (T2) of the championship, and in March (T3) and at the end of season (T4). The results showed that in the 2019/2020 season affected by the lockdown, the weight, BMI, and fat mass percentage were higher than in the previous season. Hematocrit, hemoglobin, red blood cells, and ferritin decreased during both seasons, more significantly than in the regular season. During both seasons, creatine kinase increased from T2 whilst iron concentrations decreased in T3. Testosterone increased in both seasons from T0 to T3 and returned to initial levels at T4; cortisol increased in T2 and T3 during the 2018/2019 season but not during the COVID-19 season. Physical performance tests revealed differences associated with lockdown. Thus, although from a medical point of view, none of the evaluated changes between the two seasons were clinically relevant, training at home during lockdown did not allow the players to maintain the jumping power levels typical of a competitive period.