Intra-Peritoneal Administration of Mitochondrial DNA Provokes Acute Lung Injury and Systemic Inflammation via Toll-Like Receptor 9

Autor: Lina Zhang, Shuang-ping Zhao, Yuhang Ai, Dongdong Wu, Hongyi Tan, Songyun Deng, Xiaoli Su, Pinhua Pan, Lemeng Zhang
Rok vydání: 2016
Předmět:
Lipopolysaccharides
Male
0301 basic medicine
Interleukin-1beta
mitochondrial DNA
Pharmacology
Systemic inflammation
medicine.disease_cause
p38 Mitogen-Activated Protein Kinases
lcsh:Chemistry
Pathogenesis
Mice
HMGB1 Protein
lcsh:QH301-705.5
Spectroscopy
systemic inflammation
biology
medicine.diagnostic_test
lipopolysaccharide
General Medicine
respiratory system
Computer Science Applications
medicine.symptom
Injections
Intraperitoneal

Lung injury
HMGB1
DNA
Mitochondrial

Article
Catalysis
Inorganic Chemistry
Sepsis
03 medical and health sciences
medicine
Animals
Physical and Theoretical Chemistry
Molecular Biology
Interleukin-6
Organic Chemistry
medicine.disease
respiratory tract diseases
Mice
Inbred C57BL

Toll-Like Receptor 4
030104 developmental biology
Bronchoalveolar lavage
acute lung injury
lcsh:Biology (General)
lcsh:QD1-999
Toll-Like Receptor 9
Immunology
biology.protein
TLR4
Oxidative stress
Zdroj: International Journal of Molecular Sciences, Vol 17, Iss 9, p 1425 (2016)
International Journal of Molecular Sciences
International Journal of Molecular Sciences; Volume 17; Issue 9; Pages: 1425
ISSN: 1422-0067
DOI: 10.3390/ijms17091425
Popis: The pathogenesis of sepsis is complex. Mitochondrial dysfunction, which is responsible for energy metabolism, intrinsic apoptotic pathway, oxidative stress, and systemic inflammatory responses, is closely related with severe sepsis induced death. Mitochondria DNA (mtDNA) contain un-methylated cytosine phosphate guanine (CpG) motifs, which exhibit immune stimulatory capacities. The aim of this study was to investigate the role and mechanism of mtDNA release on lipopolysaccharide (LPS) induced acute lung injury (ALI) and systemic inflammation. Following LPS injection, plasma mtDNA copies peak at 8 h. Compared with wild-type (WT) mice, mtDNA in toll like receptor 4 knockout (TLR4 KO) mice were significantly decreased. MtDNA intra-peritoneal administration causes apparent ALI as demonstrated by increased lung injury score, bronchoalveolar lavage fluid (BALF) total protein and wet/dry (W/D) ratio; mtDNA injection also directly provokes systemic inflammation, as demonstrated by increased IL-1β, IL-6, high-mobility group protein B1 (HMGB1) level; while nuclear DNA (nDNA) could not induce apparent ALI and systemic inflammation. However, compared with WT mice, TLR4 KO could not protect from mtDNA induced ALI and systemic inflammation. Specific TLR9 inhibitor, ODN 2088 pretreatment can significantly attenuate mtDNA induced ALI and systemic inflammation, as demonstrated by improved lung injury score, decreased lung wet/dry ratio, BALF total protein concentration, and decreased systemic level of IL-1β, IL-6 and HMGB1. MtDNA administration activates the expression of p-P38 mitogen-activated protein kinases (MAPK) in lung tissue and specific TLR9 inhibitor pretreatment can attenuate this activation. Thus, LPS-induced mtDNA release occurs in a TLR4-dependent manner, and mtDNA causes acute lung injury and systemic inflammation in a TLR9-dependent and TLR4-independent manner.
Databáze: OpenAIRE