A bilirubin-conjugated chitosan nanotheranostics system as a platform for reactive oxygen species stimuli-responsive hepatic fibrosis therapy

Suchithra Poilil Surendran; Reju George Thomas; Myeong Ju Moon; Rayoung Park; Jae Hyuk Lee; Yong Yeon Jeong

doi:10.1016/j.actbio.2020.09.014

A bilirubin-conjugated chitosan nanotheranostics system as a platform for reactive oxygen species stimuli-responsive hepatic fibrosis therapy

Acta Biomater. 2020 Oct 15:116:356-367. doi: 10.1016/j.actbio.2020.09.014. Epub 2020 Sep 11.

Authors

Suchithra Poilil Surendran¹, Reju George Thomas¹, Myeong Ju Moon², Rayoung Park², Jae Hyuk Lee³, Yong Yeon Jeong⁴

Affiliations

¹ Department of Biomedical Sciences, Chonnam National University Medical School, Chonnam National University Hwasun Hospital, BioMolecular Theranostics (BiT) Laboratory, South Korea; Department of Radiology, Chonnam National University Medical School, Chonnam National University Hwasun Hospital, BioMolecular Theranostics (BiT) Laboratory, South Korea.
² Department of Radiology, Chonnam National University Medical School, Chonnam National University Hwasun Hospital, BioMolecular Theranostics (BiT) Laboratory, South Korea.
³ Department of Pathology, Chonnam National University Medical School, Chonnam National University Hwasun Hospital, South Korea.
⁴ Department of Radiology, Chonnam National University Medical School, Chonnam National University Hwasun Hospital, BioMolecular Theranostics (BiT) Laboratory, South Korea. Electronic address: yjeong@jnu.ac.kr.

PMID: 32927089
DOI: 10.1016/j.actbio.2020.09.014

Abstract

The development of nanoparticles that can be used as stimuli-responsive drug carriers for the treatment of different diseases has been an emerging area of research. In this study, we designed a chitosan-bilirubin micelle (ChiBil) carrying losartan, which is responsive to intrinsic reactive oxygen species (ROS), for the treatment of hepatic fibrosis. Because bilirubin is hydrophobic in nature, its carboxyl group was conjugated to an amine group from chitosan using EDC-NHS chemistry to form an amphiphilic conjugate, ChiBil. Losartan is an angiotensin receptor blocker that reduces hepatic fibrosis, and it was used as the therapeutic payload in this study to form ChiBil-losartan micelles. The release characteristics of ChiBil-losartan were tested by ROS generation to confirm losartan release. Human hepatic stellate cell line LX2 was found to be the best in vitro model for the study. The reduction of hepatic stellate cell activation after treatment with ChiBil-losartan was analyzed based on the expression of alpha-smooth muscle actin (α-SMA) in both in vitro and in vivo studies. Advanced liver fibrosis was induced in C3H/HeN mice using a thioacetamide (TAA) via intraperitoneal injection and 10% ethanol (EtOH) in their drinking water. In addition, the hydroxyproline levels, histopathological evaluation, and mRNA quantification in the liver showed a decreased collagen content in the treated groups compared to that in the untreated control group. Macrophage infiltration studies and qPCR studies of inflammatory markers also proved the reduction of hepatic fibrosis in the treatment group. The intravenous administration of ChiBil-losartan resulted in decreased fibrosis in a TAA/EtOH-induced liver fibrosis mouse model. The in vitro and in vivo results suggest that the ROS stimuli-responsive ChiBil nanoparticles carrying losartan may be a potent therapeutic option for the treatment of hepatic fibrosis. The combined effect of losartan and bilirubin exhibited a decreased hepatic fibrosis both in vitro and in vivo.

Keywords: Bilirubin; Chitosan Nanoparticles; Liver fibrosis; Losartan; Reactive Oxygen Species (ROS).

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Bilirubin
Chitosan*
Fibrosis
Liver / pathology
Liver Cirrhosis / drug therapy
Liver Cirrhosis / pathology
Mice
Mice, Inbred C3H
Reactive Oxygen Species
Theranostic Nanomedicine

Substances

Reactive Oxygen Species
Chitosan
Bilirubin