Bioavailability by design - Vitamin D₃ liposomal delivery vehicles.

Area of Science:

• Biochemistry
• Pharmacology
• Nutrition Science

Background:

• Vitamin D3 deficiency is linked to severe health issues, including COVID-19 outcomes.
• The absorption of hydrophobic vitamin D3 is dependent on delivery vehicles like lipids and proteins.
• Effective oral formulations require mucus layer penetration and cellular uptake.

Purpose of the Study:

• To compare the efficacy of liposomal vitamin D3 versus traditional oily formulations.
• To investigate the impact of delivery vehicle on vitamin D3 absorption and plasma calcidiol levels.

Main Methods:

• Isothermal titration calorimetry and computer simulations to study vitamin D3 molecule behavior.
• A clinical experiment comparing liposomal and oily vitamin D3 formulations.
• Measurement of plasma calcidiol concentrations post-administration.

Main Results:

• Liposomal vitamin D3 rapidly increased plasma calcidiol concentrations.
• Oily vitamin D3 formulations showed no significant effect on plasma calcidiol.
• The enhancement in calcidiol levels was most pronounced in individuals with severe vitamin D3 deficiency.

Conclusions:

• Liposomal encapsulation significantly improves oral vitamin D3 bioavailability.
• The delivery vehicle plays a critical role in the absorption of hydrophobic vitamin D3.
• Liposomal vitamin D3 represents a more effective strategy for correcting vitamin D3 deficiency.