Investigation of Factors Influencing the Effectiveness of Deformable Nanovesicles for Insulin Nebulization Inhalation

Abstract

Nebulized inhalation offers a noninvasive method for delivering drugs to treat both local respiratory and systemic diseases. In this study, insulin was used as a model drug to design a series of deformable nanovesicles (DNVs) with key quality attributes, including particle size, deformability, and drug load capacity. We investigated the effects of these properties on aerosol generation, macrophage phagocytosis, and bloodstream penetration. The results showed that deformability improved nebulization performance and reduced macrophage phagocytosis, benefiting local and systemic delivery. However, the advantage of DNVs for transmembrane penetration was not evident in the alveolar epithelium. Within the size range of 80-490 nm, the smaller the particle size of IPC-DNVs, the easier it is to evade clearance by macrophages and the more effective the in vivo hypoglycemic efficacy will be. In the drug load range of 3-5 mg/mL, a lower drug load resulted in better hypoglycemic efficacy. The area above the blood glucose decline curve with time (AAC) of nebulized DNVs was 2.32 times higher than that of the insulin solution, demonstrating the feasibility and advantages of DNVs in the pulmonary delivery of biomacromolecule drugs. This study provides insights into the construction and formulation optimization of pulmonary delivery carriers.

Keywords: biomacromolecule; deformable nanovesicles; influencing factors; nebulized inhalation.

Figure 1

Nose-only exposure inhalation devise.

Figure 2

(a) FPF, (b) MMAD, and (c) GSD resulting from nebulization of IPC-DNVs with different edge activators amount (0%, 1.8%, 2.5%) nebulized by Yuwell mesh nebulizer. (n = 3). ** p < 0.01, *** p < 0.001.

Figure 3

(a) FPF, (b) MMAD, and (c) GSD resulting from nebulization of IPC-DNVs with different particle sizes (80, 150, 230, 490 nm) nebulized by Yuwell mesh nebulizer. (n = 3).

Figure 4

(a) FPF, (b) MMAD, and (c) GSD resulting from nebulization of IPC-DNVs entrapping increasing concentration of insulin (3, 4, 5 mg/mL) nebulized by Yuwell mesh nebulizer. (n = 3).

Figure 5

Fluorescence microscopy imaging of RAW264.7 cells uptaking IPC-DNVs with different edge activators amount (0%, 1.8%, 2.5%).

Figure 6

Fluorescence microscopy imaging of RAW264.7 cells uptaking IPC-DNVs with different particle sizes (80, 150, 230, 490 nm).

Figure 7

Fluorescence microscopy imaging of RAW264.7 cells uptaking IPC-DNVs entrapping increasing concentration of insulin (3, 4, 5 mg/mL).

Figure 8

Uptake of IPC-DNVs with different properties by RAW264.7 cells. (a) Relative MFI of IPC-DNVs different edge activators amount (0%, 1.8%, 2.5%). (b) Relative MFI of IPC-DNVs with different particle sizes (80, 150, 230, 490 nm). (c) Relative MFI of IPC-DNVs entrapping increasing concentration of insulin (3, 4, 5 mg/mL). * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001.

Figure 9

In vivo hypoglycemic effects of IPC-DNVs with edge activators amount (0%, 1.8%, 2.5%). (a) Percentage decrease in blood glucose levels. (b) Relative bioavailability.

Figure 10

In vivo hypoglycemic effects of IPC-DNVs with different particle sizes (80, 150, 230, 490 nm). (a) Percentage decrease in blood glucose levels. (b) Relative bioavailability. * p < 0.05.

Figure 11

In vivo hypoglycemic effects of IPC-DNVs entrapping increasing concentration of insulin (3, 4, 5 mg/mL). (a) Percentage decrease in blood glucose levels. (b) Relative bioavailability. * p < 0.05.

Figure 12

In vivo hypoglycemic effects of IPC-DNVs and insulin solution via nebulized inhalation. (a) Percentage decrease in blood glucose levels. (b) The area above the blood glucose decline curve with time. * p < 0.05.