Table 4.

Studies on the investigation of the vitamin D role in combating pulmonary and cystic fibrosis.

Study Type	Study Design	Parameter Examined	Findings	Ref
Clinical Studies	Randomized open-labeled intervention, 16 Cystic fibrosis patients receive Vitamin D3 35,000 IU/week for age < 16 years or 50,000 IU/week for age > 16 years for 3 months	T cell activation, myeloid dendritic cells.	In people with CF, vitamin D has a wide range of immunomodulatory effects	[91]
	Multicenter, randomized, double-blind, placebo-controlled intervention trial, 23 CF patients chronically affected withP. aeruginosa receive 1000 IU/d for 3 months v/s Placebo orally.	Quantification of IL-17A and IL-23.	Vitamin D had an anti-inflammatory impact, lowering the levels of IL-17A and IL-23 in CF patients’ airways. Vitamin D supplementation is recommended for CF patients.	[17]
Preclinical Studies	C57/BL6 male mice, Vitamin D I.P. daily at a dose of 5 μg/kg.	Leucocyte count, estimation of inflammatory mediators.	Vitamin D decreases leucocyte count; reduces the level of MMP-9, TGF-β IL-17, and IL-6; beneficial effect in PF treatment	[19]
	C57/BL6 mice treated with bleomycin, Vitamin D 1 μg/kg/day between 3rd day–13th days.	Level of hydroxyproline, Masson Trichrome staining and level of mRNA α-SMA, col3a1 and col1a1.	Up-regulation of mRNA of VDR level, Vitamin D hasthe potential of combating IPF.	[92]
In vitro Studies	Human myofibroblasts, Alveolar epithelial cells type II	DNA damaging	In the vicinity of a DNA damaging chemical in PF, vitamin D had an unexpectedly negative effect.	[93]