Pretreatment with Coenzyme Q10 Combined with Aescin Protects against Sepsis-Induced Acute Lung Injury

Abstract

Sepsis-associated acute lung injury (ALI) is a critical condition characterized by severe inflammatory response and mitochondrial dysfunction. Coenzyme Q10 (CoQ10) and aescin (AES) are well-known for their anti-inflammatory activities. However, their effects on lipopolysaccharide (LPS)-induced lung injury have not been explored yet. Here, we asked whether combined pretreatment with CoQ10 and AES synergistically prevents LPS-induced lung injury. Fifty male rats were randomized into 5 groups: (1) control; (2) LPS-treated, rats received a single i.p. injection of LPS (8 mg/kg); (3) CoQ10-pretreated, (4) AES-pretreated, or (5) combined-pretreated; animals received CoQ10 (100 mg/kg), AES (5 mg/kg), or both orally for 7 days before LPS injection. Combined CoQ10 and AES pretreatment significantly reduced lung injury markers; 52.42% reduction in serum C-reactive protein (CRP), 53.69% in alkaline phosphatase (ALKP) and 60.26% in lactate dehydrogenase (LDH) activities versus 44.58, 37.38, and 48.6% in CoQ10 and 33.81, 34.43, and 39.29% in AES-pretreated groups, respectively. Meanwhile, combination therapy significantly reduced interleukin (IL)-1β and tumor necrosis factor (TNF)-α expressions compared to monotherapy (p < 0.05). Additionally, combination therapy prevented LPS-induced histological and mitochondrial abnormalities greater than separate drugs. Western blotting indicated that combination therapy significantly suppressed nucleotide-binding oligomerization domain (NOD)-like receptors-3 (NLRP-3) inflammasome compared to separate drugs (p < 0.05). Further, combination therapy significantly decreased the expression of signaling cascades, p38 mitogen-activated protein kinases (p38 MAPK), nuclear factor kappa B (NF-κB)-p65, and extracellular-regulated kinases 1/2 (ERK1/2) versus monotherapy (p < 0.05). Interestingly, combined pretreatment significantly downregulated high mobility group box-1 (HMGB1) by 72.93%, and toll-like receptor 4 (TLR4) by -0.93-fold versus 61.92%, -0.83-fold in CoQ10 and 38.67%, -0.70-fold in AES pretreatment, respectively. Our results showed for the first time that the enhanced anti-inflammatory effect of combined CoQ10 and AES pretreatment prevented LPS-induced ALI via suppression of NLRP-3 inflammasome through regulation of HMGB1/TLR4 signaling pathway and mitochondrial stabilization.

Keywords: Acute lung injury; HMGB1/TLR4; Mitochondrial abnormalities; NLRP-3 inflammasome; Pyroptosis; Sepsis.