Effects of Particle Size of Curcumin Solid Dispersions on Bioavailability and Anti-Inflammatory Activities

Abstract

The delivery of curcumin (CUR) using the solid dispersion system (CUR solid dispersions; C-SDs) has been shown to improve CUR bioavailability. However, it is unclear how different particle sizes of C-SDs affect the bioavailability and biological activities of CUR. Hence, we prepared C-SDs in different sizes using food-grade excipients and evaluated their bioavailability and biological activities. By pulverizing large particle sizes of C-SDs using zirconia beads, we successfully prepared C-SDs I-IV (particle size: (I) 120, (II) 447, (III) 987, (IV) 1910 nm). When administrated orally in rats, the bioavailability of CUR was increased with decreasing C-SDs size, most likely by improving its solubility in micelles. When administrated intravenously in rats, blood concentrations of CUR were increased with increasing particle size, suggesting that larger C-SDs presumably control the metabolic conversion of CUR. In RAW264 cells, more CUR was taken up by cells as their sizes reduced, and the more potent their anti-inflammatory activities were, suggesting that smaller C-SDs were taken up through a number of cellular uptake pathways. Altogether, the present study showed an evident effect of C-SDs size on their bioavailability and anti-inflammatory activities—information that serves as a basis for improving the functionality of CUR.

Enhancing the Bioavailability and Bioactivity of Curcumin for Disease Prevention and Treatment

“…A review of 11 curcumin nanoformulations tested in clinical studies showed increased relative bioavailability (RB) ranging from 9- to 185-fold, but an analysis of the design of these studies, curcumin dosage, administration, analytical method, pharmacokinetic parameters, and the composition of study population revealed differences that make it difficult to compare these RB numbers directly [ 52 ]. Not only the composition of nanoparticles affects the bioavailability, but also particle size and route of administration [ 53 ], e.g., for curcumin prepared as solid dispersions, a smaller particle size increased the bioavailability when administered orally, whereas a larger particle size increased the bioavailability when administered intravenously [ 54 ].…”

A Review of Recent Curcumin Analogues and Their Antioxidant, Anti-inflammatory and Anticancer Activities

“…Studies have indicated that curcumin inhibits various inflammatory pathways, including lipo-oxygenase and cyclo-oxygenase activities, nitric oxide production and ROS generation in different cell types (Hatcher et al, 2008). Kato et al (2023) investigated the anti-inflammatory activities of curcumin solid dispersions (C-SDs) in rats. They observed that smaller particle sizes of C-SDs were associated with increased bioavailability and anti-inflammatory effects.…”