Nanostructured lipid carrier potentiated oral delivery of raloxifene for breast cancer treatment

Nanotechnology. 2020 Nov 20;31(47):475101. doi: 10.1088/1361-6528/abaf81.

Abstract

Nanotherapeutics in cancer treatment are dominating global science and research, and have been recognized as the pioneering medical care regimen. Raloxifene (RLN) has been used for its anti-proliferative action on mammary tissue, however, it suffers from poor oral bioavailability. This investigation gives an account of the design and development of RLN-loaded nanostructured lipid carriers (RLN-NLCs) using a simple and scalable ultrasonication method for improved oral efficacy and limited offsite toxicity using Compritol® 888 ATO as a solid lipid and Transcutol® HP as a liquid lipid. In addition, the optimized RLN-NLCs were in the nanometric range (121 nm) with high % entrapment efficiency (%EE) (81%) for RLN, and were further freeze-dried in the presence of mannitol to enhance the stability of RLN-NLCs in the dry state for long-term use. Morphological observation under a transmission electron microscope and scanning electron microscope revealed the spherical smooth surface nanometric size of RLN-NLCs. Powder x-ray diffraction confirmed the encapsulation of RLN into the RLN-NLC's matrix with reduced crystallinity of the drug. The in vitro release study showed a burst release for an initial 4 h, and sustained release for up to 24 h. Furthermore, the RLN-NLCs showed higher cytotoxicity towards MCF-7 cells in vitro in comparison to RLN suspension, and an ex vivo intestinal permeation study demonstrated improved intestinal permeability of RLN-NLCs. Moreover, the in vivo pharmacokinetic study in female Wistar rats showed a 4.79-fold increment in oral bioavailability of RLN from RLN-NLCs compared to RLN suspension. Taken together, our results pave the way for a new nanotherapeutic approach towards breast cancer treatment.

MeSH terms

  • Administration, Oral
  • Animals
  • Antineoplastic Agents / administration & dosage*
  • Antineoplastic Agents / pharmacokinetics
  • Antineoplastic Agents / pharmacology
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / pathology
  • Drug Carriers / chemistry*
  • Ethylene Glycols / chemistry*
  • Fatty Acids / chemistry*
  • Female
  • Humans
  • MCF-7 Cells
  • Nanostructures / chemistry
  • Raloxifene Hydrochloride / administration & dosage*
  • Raloxifene Hydrochloride / pharmacokinetics
  • Raloxifene Hydrochloride / pharmacology
  • Rats, Wistar
  • Selective Estrogen Receptor Modulators / administration & dosage
  • Selective Estrogen Receptor Modulators / pharmacokinetics
  • Selective Estrogen Receptor Modulators / pharmacology

Substances

  • Antineoplastic Agents
  • Drug Carriers
  • Ethylene Glycols
  • Fatty Acids
  • Selective Estrogen Receptor Modulators
  • glyceryl behenate
  • Raloxifene Hydrochloride
  • carbitol