Current Overview on Therapeutic Potential of Vitamin D in Inflammatory Lung Diseases

Vitamin D: A Nutraceutical Supplement at the Crossroad Between Respiratory Infections and COVID-19

Even though in mid-2023 the World Health Organization declared the end of the public health emergency of international concern status for COVID-19, many areas of uncertainty about SARS-CoV-2 infection pathophysiology remain. Although in the last 4 years pharmaceutical industries widely invested in the development of effective antiviral treatments and vaccines, large disparities in their availability worldwide still exist, thus fostering the investigation of nutritional supplements as adjuvant therapeutic approaches for disease management, especially in resource-limited settings. During the COVID-19 pandemic, vitamin D has been widely used as an over-the-counter solution to improve disease evolution, thanks to its known immunomodulatory and anti-inflammatory actions. Ecological and observational studies support a relationship between hypovitaminosis D and COVID-19 negative outcomes and, according to this evidence, several research groups investigated the role of vitamin D supplementation in protecting from SARS-CoV-2 infection and/or improving disease evolution. This narrative review is intended to offer insights into the existing data on vitamin D's biological effects in respiratory infections, especially in COVID-19. Furthermore, it will also offer a brief overview of the complex interplay between vitamin D and vaccine-elicited immune response, with special attention to anti-COVID-19 vaccines.

Vitamin D supplementation may be beneficial in improving the prognosis of patients with chronic obstructive pulmonary disease in the intensive care unit: a retrospective study

Background

Vitamin D is a crucial fat-soluble vitamin that has garnered significant attention due to its potential impact on respiratory health. It is noteworthy that many patients with chronic obstructive pulmonary disease (COPD) often experience deficiencies or insufficiencies of vitamin D. To address this issue, our retrospective study aimed to explore the potential association between serum 25-hydroxyvitamin D concentration and the prognoses of COPD patients in the Intensive Care Unit (ICU).

Methods

This study utilised data from the Medical Information Marketplace in Intensive Care IV (MIMIC-IV), a database of patients admitted to the Intensive Care Unit at Beth Israel Deaconess Medical Center (BIDMC) in the United States of America, with a focus on patients with a diagnosis of COPD. These patients were categorized into two groups: those who received vitamin D supplementation during their ICU stay and those who did not. We assessed in-hospital mortality and ICU mortality outcomes. Our analysis involved various analytical tools, including Kaplan-Meier survival curves, Cox proportional risk regression models, and subgroup analyses, to investigate the relationship between vitamin D supplementation and these outcomes. Additionally, we employed propensity-score matching (PSM) to enhance the reliability of our findings.

Results

The study included a total of 3,203 COPD patients, with 587 in the vitamin D group and 2,616 in the no-vitamin D group. The Kaplan-Meier survival curve demonstrated a significant difference in survival probability between the two groups. After adjusting for potential confounders using Cox regression models, the vitamin D group exhibited a substantially lower risk of in-hospital and ICU mortalities compared to the no-vitamin D group. The hazard ratios for in-hospital and ICU mortalities in the vitamin D group were 1.7 (95% CI: 1.3, 2.3) and 1.8 (95% CI: 1.2, 2.6), respectively. Propensity-score matching (PSM) estimation yielded consistent results. Furthermore, in the subgroup analysis, female patients who received vitamin D supplementation showed a reduced risk of in-hospital mortality.

Conclusion

The study suggests that vitamin D supplementation may be linked to a reduction in in-hospital and ICU mortalities among COPD patients in the ICU. Of particular note is the potential benefit observed in terms of in-hospital mortality, especially for female patients.

Bioconversion of vitamin D3 into calcitriol by Actinomyces hyovaginalis isolate CCASU- A11-2

Vitamin D₃ is a fat-soluble prohormone that is activated inside the liver to produce 25-hydroxyvitamin D₃ (calcidiol), and in the kidney to produce the fully active 1α, 25-dihydroxy vitamin D₃ (calcitriol). A previous work piloted in our laboratory, resulted in a successful recovery of a local soil-promising Actinomyces hyovaginalis isolate CCASU-A11-2 capable of converting vitamin D₃ into calcitriol. Despite the rising amount of research on vitamin D₃ bioconversion into calcitriol, further deliberate studies on this topic can significantly contribute to the improvement of such a bioconversion process. Therefore, this work aimed to improve the bioconversion process, using the study isolate, in a 14 L laboratory fermenter (4 L fermentation medium composed of fructose (15 g/L), defatted soybean (15 g/L), NaCl (5 g/L), CaCO₃ 2 g/L); K₂HPO₄, (1 g/L) NaF (0.5 g/L) and initial of pH 7.8) where different experiments were undertaken to investigate the effect of different culture conditions on the bioconversion process. Using the 14 L laboratory fermenter, the calcitriol production was increased by about 2.5-fold (32.8 µg/100 mL) to that obtained in the shake flask (12.4 µg/100 mL). The optimal bioconversion conditions were inoculum size of 2% v/v, agitation rate of 200 rpm, aeration rate of 1 vvm, initial pH of 7.8 (uncontrolled); addition of vitamin D₃ (substrate) 48 h after the start of the main culture. In conclusion, the bioconversion of vitamin D₃ into calcitriol in a laboratory fermenter showed a 2.5-fold increase as compared to the shake flask level where, the important factors influencing the bioconversion process were the aeration rate, inoculum size, the timing of substrate addition, and the fixed pH of the fermentation medium. So, those factors should be critically considered for the scaling-up of the biotransformation process.

Polymorphisms in VDR, CYP27B1, CYP2R1, GC and CYP24A1 Genes as Biomarkers of Survival in Non-Small Cell Lung Cancer: A Systematic Review

The objective of this systematic review was to provide a compilation of all the literature available on the association between single-nucleotide polymorphisms (SNPs) in the genes involved in the metabolic pathway of vitamin D and overall survival (OS) and progression-free survival (PFS) in patients with non-small cell lung cancer (NSCLC). This systematic review was conducted in accordance with the PRISMA guidelines. It included all the literature published up to 1 November 2022 and was carried out in four databases (Medline [PubMed], Scopus, Web of Science, and Embase), using the PICO strategy, with relevant keywords related to the objective. The quality of the studies included was evaluated with an assessment tool derived from the Strengthening the Reporting of Genetic Association Studies (STREGA) statement. Six studies were included in this systematic review. Our findings showed that the BsmI (rs1544410), Cdx-2 (rs11568820), FokI (rs2228570), ApaI (rs7975232), TaqI (rs731236), rs4646536, rs6068816, rs7041, and rs10741657 SNPs in the genes that play a part in vitamin D synthesis (CYP2R1, CYP27B1), transport (GC), and metabolism (CYP24A1), as well as in the vitamin D receptor (VDR), are associated with OS and/or PFS in patients with NSCLC. The SNPs in VDR have been the most extensively analyzed. This systematic review summed up the available evidence concerning the association between 13 SNPs in the main genes involved in the vitamin D metabolic pathway and prognosis in NSCLC. It revealed that SNPs in the VDR, CYP27B1, CYP24A1, GC, and CYP2R1 genes could have an impact on survival in this disease. These findings suggest the identification of prognostic biomarkers in NSCLC patients. However, evidence remains sparse for each of the polymorphisms examined, so these findings should be treated with caution.

Vitamin D in Health and Disease

Vitamin D (VD) is a fat-soluble hormone that plays a fundamental role not only in calcium homeostasis and bone metabolism, but also has anti-inflammatory and antioxidant properties, acting on both innate and adaptive immunity [...].