Co-administration of vitamin D3 and Lacticaseibacillus paracasei DG increase 25-hydroxyvitamin D serum levels in mice

Abstract

Purpose: Subclinical vitamin D (vitD) deficiency enhances the predisposition to a myriad of acute and chronic pathologies in many people worldwide. Due to the scarcity of vitD-rich foods, the consumption of supplements or fortified foods can be required to maintain healthy serum levels of 25-hydroxyvitamin D [25(OH)D], and the major circulating form of vitD that is commonly measured in serum to determine the vitD status. Since the vitD absorption seems to resemble that of lipids, improved emulsification in the gut could favor vitD permeation through the enterocyte membrane. Contextually, we hypothesized that a microorganism with cholecalciferol (vitD3)-solubilization properties may potentially result in enhanced serum vitD levels.

Methods and results: Six probiotic strains were screened for their ability to create a stable suspension of vitD3 in water: Lacticaseibacillus paracasei DG, L. paracasei LPC-S01, L. paracasei Shirota, L. rhamnosus GG, Limosilactobacillus reuteri DSM 17938, and Lactobacillus acidophilus LA5. The DG strain displayed the strongest vitD3 solubilization ability and, consequently, were used in an in vivo trial where a commercial preparation of vitD3 in refined olive oil was administered by gavage to CD-1 mice with or without the concurrent administration of L. paracasei DG. ELISA measurements showed that the DG strain significantly increased the serum levels of 25(OH) D when administered once a day for 1 week in association with the vitD3 supplement.

Conclusion: This preliminary pre-clinical study suggests that the combined administration of L. paracasei DG with an oil-based cholecalciferol supplement could contribute to the maintenance of the adequate 25(OH) D serum levels in people at risk of vitD deficiency.

Keywords: Bioavailability; Biosurfactant; Cholecalciferol supplementation; Probiotics; Vitamin D.

Fig. 1

Cholecalciferol-emulsification properties of Lactobacillaceae probiotic strains. Statistically significant differences were determined through unpaired t test with Welch’s correction (n=3) performed after the Levene’s test, which evidenced that the variance between groups was different (Levene’s P= 0.005). **P<0.01; *P<0.05

Fig. 2

Design of the trial in mouse model. Vehicle, vitamin D3, and L. paracasei DG cells were administered to mice by gavage. Vehicle consisted of an aqueous solution of sucrose 20% + glycerol 10% (w/vol). Bacterial cells were suspended in the same vehicle. *500 IU of vitamin D3 in refined olive oil (DIBASE) were administered per single gavage. **10⁸ CFUs of L. paracasei DG were administered per single gavage

Fig. 3

Levels of 25-hydroxyvitamin D [25(OH)D] in mouse serum samples collected 3 h after the last gavage, as determined through ELISA measurements. Red symbols (+) indicate the mean. Lacticaseibacillus paracasei DG cells were administered to mice by gavage once a day for 1 week. Sample groups (from I to VI) are according to Fig. 2. − not administered; + administered. SD, single-dose administration of vitamin D3; D1W, daily administration of vitamin D3 for 1 week. Statistically significant differences were determined through unpaired t test with Welch’s correction (n=3) performed after the Levene’s test, which evidenced that the variance between groups was different (Levene’s P= 0.021). ****P<0.0001; ***P<0.001; **P<0.01