Faculty Collaboration Database

Nanoliposomes protect against AL amyloid light chain protein-induced endothelial injury. J Liposome Res 2014 Mar;24(1):69-73

Date

11/19/2013

Pubmed ID

24236475

Pubmed Central ID

PMC3925072

DOI

10.3109/08982104.2013.838258

Scopus ID

2-s2.0-84893272416 (requires institutional sign-in at Scopus site)   13 Citations

Abstract

CONTEXT: A newly-recognized pathogenic mechanism underlying light chain amyloidosis (AL) involves endothelial dysfunction and cell injury caused by misfolded light chain proteins (LC). Nanoliposomes (NL) are artificial phospholipid vesicles that could attach to misfolded proteins and reduce tissue injury.

OBJECTIVE: To test whether co-treatment with NL reduces LC-induced endothelial dysfunction and cell death.

METHODS: Abdominal subcutaneous adipose arterioles from 14 non-AL subjects were cannulated; dilator response to acetylcholine and papaverine were measured at baseline and following 1-hour exposure to LC (20 µg/mL, 2 purified from AL subjects' urine, 1 from human recombinant LC [AL-09]) ± NL (phosphatidylcholine/cholesterol/phosphatidic acid 70/25/5 molar ratio) or NL alone. Human aortic artery endothelial cells (HAEC) were exposed to Oregon Green-labeled LC ± NL for 24 hours and intracellular LC and apoptosis (Hoechst stain) were measured. Circular dichroism spectroscopy was performed on AL-09 LC ± NL to follow changes in secondary structure and protein thermal stability.

RESULTS: LC caused impaired dilation to acetylcholine that was restored by NL (control - 94.0 ± 1.8%, LC - 65.0 ± 7.1%, LC + NL - 95.3 ± 1.8%, p ≤ 0.001 LC versus control or LC + NL). NL protection was inhibited by L-NG-nitroarginine methyl ester. NL increased the beta sheet structure of LC, reduced endothelial cell internalization of LC and protected against LC-induced endothelial cell death.

CONCLUSIONS: LC induced human adipose arteriole endothelial dysfunction and endothelial cell death, which were reversed by co-treatment with NL. This protection may partly be due to enhancing LC protein structure and reducing LC internalization. Nanoliposomes represent a promising new class of agents to ameliorate tissue injury from protein misfolding diseases such as AL.

Author List

Truran S, Weissig V, Ramirez-Alvarado M, Franco DA, Burciu C, Georges J, Murarka S, Okoth WA, Schwab S, Hari P, Migrino RQ

Author

Parameswaran Hari MD Adjunct Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Aged
Amyloid
Amyloidosis
Apoptosis
Endothelium
Heart Failure
Humans
Liposomes
Male
Middle Aged
Nanoparticles
Proteostasis Deficiencies