Cardiolipin in Immune Signaling and Cell Death
TRENDS IN CELL BIOLOGY
Authors: Pizzuto, Malvina; Pelegrin, Pablo
Abstract
Cardiolipin (CL) is a tetra-acylated diphosphatidylglycerol lipid. In physiological conditions, CL presents unsaturated chains and is located in the inner mitochondria membrane (IMM). Dead signals, infection, or disease may change the level of CL saturation and oxidation and cause its translocation to the cytosolic side of the outer mitochondria! membrane (OMM), affecting mitochondrial function and the inflammatory response. In this review, we summarize the emerging proapoptotic, pro-, and anti-inflammatory functions of cytosolic-exposed CL and how they are regulated by CL chain saturation and oxidation. We underline how the unique dimeric phospholipid structure confers peculiar properties on CL in the regulation of cell death and immune system proteins, such as the Nucleotide-binding domain and leucine-rich repeat-containing pyrin protein 3 (NLRP3), caspases (Casp), and Toll-like receptor 4 (TLR4). We also provide an overview of the human diseases in which CL deficiency or modification are implicated and of the use of exogenous unsaturated CL (uCL) as a novel therapeutic approach.
Euterpe oleraceaMart. (Acai) attenuates experimental colitis in rats: involvement of TLR4/COX-2/NF-B
INFLAMMOPHARMACOLOGY
Authors: Monteiro, Carlos Eduardo da Silva; da Costa Filho, Humberto Barbosa; Silva, Francisca Gessica Oliveira; de Souza, Maria de Fathima Felipe; Sousa, Johnatan Alisson Oliveira; Franco, Alvaro Xavier; Resende, Angela Castro; de Moura, Roberto Soares; de Souza, Marcellus Henrique Loiola; Soares, Pedro Marcos Gomes; Barbosa, Andre Luiz dos Reis
Abstract
Euterpe oleraceaMart., commonly known as acai, has been demonstrated to exhibit significantly antioxidant and inflammatory activities in experimental models. These effects of the hydroalcoholic extract from the acai seed (ASE) were investigated in TNBS-induced (2,4,6-trinitrobenzenesulfonic acid) acute colitis model in rats. Wistar rats (180-220 g) were orally pretreated with saline (0.3 mL), ASE (10, 30 and 100 mg/kg) and dexamethasone (control group, 1 mg/kg) once daily for 3 days starting before TNBS instillation. On day 3 after TNBS, the animals were euthanized, the portion of distal colon was collected and washed with 0.9% saline for macroscopy and histological evaluation, glutathione (GSH) and malonyldialdehyde (MDA) levels, myeloperoxidase (MPO) and catalase (CAT) activity, nitrate and nitrite (NO3/NO2) concentration, pro-inflammatory cytokines levels and intestinal barrier integrity. We also evaluated Toll-like Receptor 4/cyclooxygenase-2/nuclear factor kappa B expression as a possible mechanism related to the ASE effects. Treatment with ASE 100 mg/kg decreased significantly macroscopic and microscopic damage induced by TNBS. In addition, MPO activity, TNF-alpha (tumor necrosis factor-alpha) and IL-1 beta (interleukin 1) levels were reduced in rats with colitis. ASE 100 mg/kg restored GSH and MDA levels, CAT activity, NO3/NO(2)concentration and improved the intestinal barrier integrity in the TNBS group. ASE 100 mg/kg significantly reduced TNBS-induced expression of the TLR4, COX-2 and NF-kappa B p65. ASE 100 mg/kg improved macroscopy and histological parameters, inflammation, intestinal barrier integrity and nitric and oxidative stress through the TLR-4/COX-2/NF-kappa B pathway.