Anti-Obesity Effect of α-Cubebenol Isolated from Schisandra chinensis in 3T3-L1 Adipocytes

The efficacy of α-cubebenol isolated from Schisandra chinensis has been studied in several diseases, including cecal ligation, puncture challenge-induced sepsis, and degranulation of neutrophils. To identify the novel functions of α-cubebenol on lipid metabolism, alterations on the regulation of lipogenesis, lipolysis, and inflammatory response were observed in 3T3-L1 adipocytes treated with α-cubebenol. Most lipogenic targets, including lipid accumulation, level of lipogenic transcription factors, and expression of lipogenic regulators, were suppressed in MDI (3-isobutyl-1-methylxanthine, dexamethasone, and insulin)-stimulated 3T3-L1 adipocytes treated with α-cubebenol without significant cytotoxicity. In addition, similar inhibition effects were observed in the iNOS-induced COX-2 mediated pathway and NLRP3 inflammasome pathway of MDI-stimulated 3T3-L1 cells treated with α-cubebenol. Lipolytic targets, such as cAMP concentration, expression of adenylyl cyclase and PDE4, and their downstream signaling pathway, in MDI-stimulated 3T3-L1 cells were stimulated by the α-cubebenol treatment. The levels of transcription factors and related proteins for β-oxidation were significantly higher in the MDI + α-cubebenol treated group than in the MDI + Vehicle treated group. These results show that α-cubebenol has a novel role as a lipogenesis inhibitor, lipolysis and β-oxidation stimulator, and inflammasome suppressor in MDI-stimulated 3T3-L1 adipocytes.

Melatonin Alleviates Cardiac Function in Sepsis-Caused Myocarditis via Maintenance of Mitochondrial Function

Melatonin (N-acetyl-5-methoxytryptamine) has been shown to have a cardioprotective effect against myocarditis. However, the mechanisms underlying the protective role of melatonin (MLT) in sepsis-induced myocarditis are yet to be revealed. In this study, MLT was administrated to mice, 14 days before cecal ligation puncture surgery. Echocardiography results showed that MLT alleviated cardiac dysfunction in sepsis-induced myocarditis. Furthermore, MLT reduced cardiac inflammation by inhibiting the expression of Il-1α, Il-1β, Il-6, and Mcp-1 messenger RNA (mRNA) levels. The RNA sequencing (RNA-seq) assays with heart tissues showed that MLT maintains the mitochondrial function in sepsis-caused myocarditis. Additionally, the production of reactive oxygen species (ROS) in heart tissues was suppressed by MLT. Taken together, in evaluating the therapeutic effect of MLT on sepsis-induced myocarditis, the results showed that MLT alleviated cardiac damage by regulating mitochondrial function and mitochondrial ROS.

Methotrexate Ameliorates Systemic Inflammation and Septic Associated-Lung Damage in a Cecal Ligation and Puncture Septic Rat Model

Background: Sepsis is a serious, heterogeneous clinical entity produced by a severe and systemic host inflammatory response to infection. Methotrexate (MTX) is a folate-antagonist that induces the generation of adenosine and also inhibits JAK/STAT pathway; MTX it is widely used as an anti-inflammatory drug to control the immune system. Objective: The aim of this study was to assess the beneficial effects of a single and low dose of MTX in the systemic response and acute lung injury (ALI) induced by sepsis. As in the clinics, we treated our animals with antibiotics and fluids and performed the source control to mimic the current clinic treatment. Methods and main results: Sepsis was induced in rats by a cecal ligation puncture (CLP) procedure. Six hours after induction of sepsis, we proceeded to the source control; fluids and antibiotics were administered at 6 h and 24 h after CLP. MTX (2.5 mg/Kg) was administered 6 h after the first surgery in one CLP experimental group and to one Sham group. A protective effect of MTX was observed through a significant reduction of pro-inflammatory cytokines and a decrease infiltration of inflammatory cells in the lung. In addition, we found a regulation in adenosine receptor A2aR and the metalloproteinases by MTX. Conclusion: A single, low dose of MTX attenuates sepsis lung-associated damage by decreasing pro-inflammatory response, infiltration of pro-inflammatory cells and avoiding defective tissue lung remodeling.

Melatonin Alleviates Renal Injury in Mouse Model of Sepsis

Melatonin (N-acetyl-5-methoxytryptamine; MLT) has been shown to have a renal-protective effect against kidney injury. However, the mechanisms underlying the protective role of MLT in sepsis-induced renal injury are yet to be revealed. In this study, MLT alleviated renal dysfunction with the increase of BUN (blood urea nitrogen) and SCR (serum creatinine) and reduction of fibrosis in the CLP (cecal ligation puncture) model. RNA-seq analysis showed that MLT repressed the oxidant stress in response to kidney injury. Our in vitro study showed that MLT suppresses LPS-induced accumulation of ROS (reactive oxygen species) production via SOD2 downregulation and Nox4 upregulation in HK-2 cells. Furthermore, we found that MLT alleviated the inflammatory response, with the mRNA-level reduction of Il-1α, Il-1β, Mcp-1, and Tgf-β1. Taken together, in evaluating the therapeutic effect of MLT on sepsis-induced acute kidney injury, the results showed that MLT alleviated renal damage by regulating the production of ROS.

Mitoquinone Mesylate (MitoQ) Prevents Sepsis Induced Diaphragm Dysfunction

Sepsis-induced diaphragm dysfunction is a major contributor to respiratory failure in mechanically ventilated patients. There are no pharmacological treatments for this syndrome, but studies suggest that diaphragm weakness is linked to mitochondrial free radical generation. We hypothesized that administration of mitoquinone mesylate (MitoQ), a mitochondrially targeted free radical scavenger, would prevent sepsis- induced diaphragm dysfunction. We compared diaphragm function in 4 groups of male mice: (a) sham operated controls treated with saline (0.3 ml intraperitoneally, IP), (b) sham operated mice treated with MitoQ (3.5 mg/kg/day given IP in saline), (c) cecal ligation puncture (CLP) mice treated with saline, and (d) CLP mice treated with MitoQ. Forty-eight hours after surgery, we assessed diaphragm force generation, myosin heavy chain content, mitochondrial oxygen consumption (OCR) and aconitase activity. We also determined the effect of MitoQ administration in female mice with CLP sepsis and in mice with endotoxin-induced sepsis. CLP decreased diaphragm specific force generation and MitoQ prevented these decrements (e.g. maximal force averaged 30.2 ± 1.3, 28.0 ± 1.3, 12.8 ± 1.9 and 30.0 ± 1.0 N/cm2 for sham, sham + MitoQ, CLP, and CLP + MitoQ groups, p<0.001). CLP also reduced diaphragm mitochondrial OCR and MitoQ blocked this effect. Similar responses were observed in female mice, and in endotoxin-induced sepsis. Moreover, delayed MitoQ treatment was as effective as immediate treatment. These data indicate that MitoQ prevents sepsis-induced diaphragm dysfunction, preserving force generation and reducing fatigue. MitoQ may be a useful therapeutic agent to preserve diaphragm function in septic, critically ill patients.

Transglutaminase 2 as a Marker for Inflammation and Therapeutic Target in Sepsis

Sepsis results in lethal organ malfunction due to dysregulated host response to infection, which is a condition with increasing prevalence worldwide. Transglutaminase 2 (TG2) is a crosslinking enzyme that forms a covalent bond between lysine and glutamine. TG2 plays important roles in diverse cellular processes, including extracellular matrix stabilization, cytoskeletal function, cell motility, adhesion, signal transduction, apoptosis, and cell survival. We have shown that the co-culture of Candida albicans and hepatocytes activates and induces the translocation of TG2 into the nucleus. In addition, the expression and activation of TG2 in liver macrophages was dramatically induced in the lipopolysaccharide-injected and cecal ligation puncture-operated mouse models of sepsis. Based on these findings and recently published research, we have reviewed the current understanding of the relationship between TG2 and sepsis. Following the genetic and pharmacological inhibition of TG2, we also assessed the evidence regarding the use of TG2 as a potential marker and therapeutic target in inflammation and sepsis.

TREATMENT OF ABDOMINAL SEPSIS WITH LEVAMISOLE AND PERITONEAL LAVAGE IN RATS

Introduction: Intra-abdominal sepsis is one of the most difficult situations in surgery and usually presents as a peritonitis. It is a systemic inflammatory response to infection that is often associated with hypoperfusion followed by tissue injury and organ failure. Given that its the sequelae reflect the increasing severity of the systemic response to infection, a correct and early treatment needs to be established. In this sense, the study analyzes the effect of peritoneal lavage and the use of the isomers immunomodulator in the treatment of abdominal sepsis in rats. Methods: The animals were randomly assigned to three groups A (control), B (peritoneal lavage), C (levamisole). All groups underwent laparotomy, anesthesia and cecal ligation/puncture. A ten-parameter clinical score was analyzed, which allowed the classification of sepsis degree, peritoneal fluid cultures, and cytokine dosage. Results: Group C had better scores on the clinical score and also lower growth of bacterial colonies in cultures. A lower dosage of TNF-alpha, IL-Ib, IL-6 and PCR in group C was observed, compared to groups A and B. Conclusion: Levamisole positively influenced the treatment in the parameters analyzed compared to the peritoneal lavage group and the control group.

Trigonoside II mitigates sepsis-induced myocardial injury via reduction in oxidative stress and regulation of TLR- 4/NF-kB inflammatory pathway

Purpose: To investigate the protective effect of trigonoside II against sepsis-induced myocardial injury in rats, and the mechanism involved. Methods: Adult male Sprague Dawley rats (n = 30) weighing 200 - 230 g (mean weight = 215 ± 15 g) were used for this study. The rats were randomly assigned to 3 groups (10 rats/group): sham, cecal ligation puncture (CLP), and trigonoside II. Rats in the treatment group received trigonoside II at a dose of 2 mg/kg intraperitoneally (i.p.) at 3, 12 and 24 h post-surgery. Sepsis was induced using CLP method. Lactate dehydrogenase (LDH) and creatine kinase (CK-MB) activities, and hemodynamic functions were determined in the rats. The levels of interleukin (IL)-1β and IL-6, and tumor necrosis factor α (TNF-α) were assayed in rat serum. Oxidative stress and myocardial cell apoptosis were determined by measuring malondialdehyde (MDA) levels, while activities of glutathione peroxidase (GPx), superoxide dismutase (SOD) and myeloperoxidase (MPO), as well as levels of expression of bax, bcl-2 and caspase-3 were also assessed. Results: Treatment of myocardial injury rats with trigonoside II led to significant reductions in the activities of LDH, CK-MB and MPO, and decreases in levels of IL-1β, IL-6 and TNF-α (p < 0.05). It also significantly reversed the effects of sepsis on rat hemodynamic functions (p < 0.05). Trigonoside IItreatment significantly reduced MDA levels in rat myocardial tissues, but significantly increased SOD and GPx activities (p < 0.05). It significantly down-regulated protein expressions of NF-kB and TLR-4 in myocardial tissues (p < 0.05). The number of apoptotic cells and activity of caspase-3 were significant increased in myocardial tissues of rats in CLP group, when compared with sham group, but were reduced significantly in myocardial tissues of trigonoside II-treated rats (p < 0.05). Similarly, trigonoside II treatment down-regulated the protein expressions of caspase-3 and bax, but upregulated bcl-2 protein expression in the rat myocardial tissues (p < 0.05). Conclusion: The results of this study indicate that trigonoside II confers protection on sepsis-induced myocardial injury via reduction in oxidative stress and regulation of TLR-4/NF-kB inflammatory pathway. Keywords: Cecal ligation puncture, Myocardial injury, Oxidative stress, Sepsis, Trigonoside II