Mice with heterozygous deficiency of lipoic acid synthase have an increased
sensitivity to lipopolysaccharide-induced tissue injury.
Authors Yi X, Kim K, Yuan W, Xu L, Kim HS, Homeister JW, Key NS, Maeda N
Submitted By Nobuyo Maeda on 2/8/2009
Status Published
Journal Journal of leukocyte biology
Year 2009
Date Published 1/1/2009
Volume : Pages 85(1) : 146 - 153
PubMed Reference 18845616
Abstract Alpha-lipoic acid (1, 2-dithiolane-3-pentanoic acid; LA), synthesized in
mitochondria by LA synthase (Lias), is a potent antioxidant and a cofactor for
metabolic enzyme complexes. In this study, we examined the effect of genetic
reduction of LA synthesis on its antioxidant and anti-inflammatory properties
using a model of LPS-induced inflammation in Lias+/- mice. The increase of
plasma proinflammatory cytokine, TNF-alpha, and NF-kappaB at an early phase
following LPS injection was greater in Lias+/- mice compared with Lias+/+ mice.
The circulating blood white blood cell (WBC) and platelet counts dropped
continuously during the initial 4 h. The counts subsequently recovered partially
in Lias+/+ mice, but the recovery was impaired totally in Lias+/- mice.
Administration of exogenous LA normalized the recovery of WBC counts in Lias+/-
mice but not platelets. Enhanced neutrophil sequestration in the livers of
Lias+/- mice was associated with increased hepatocyte injury and increased gene
expression of growth-related oncogene, E-selectin, and VCAM-1 in the liver
and/or lung. Lias gene expression in tissues was 50% of normal expression in
Lias+/- mice and reduced further by LPS treatment. Decreased Lias expression was
associated with diminished hepatic LA and tissue oxidative stress. Finally,
Lias+/- mice displayed enhanced mortality when exposed to LPS-induced sepsis.
These data demonstrate the importance of endogenously produced LA for preventing
leukocyte accumulation and tissue injury that result from LPS-induced
inflammation.


Investigators with authorship
NameInstitution
Nobuyo MaedaUniversity of North Carolina
Haitao YuanBeth Israel Deaconess Medical

Complications









Genes
SymbolDescription
Liaslipoic acid synthetase
Nfkb1nuclear factor of kappa light chain gene enhancer in B-cells 1, p105
Seleselectin, endothelial cell
Tnftumor necrosis factor
Vcam1vascular cell adhesion molecule 1