scholarly journals Hypocalcemia in sepsis: analysis of the subcellular distribution of Ca2+ in septic rats and LPS/TNF-α-treated HUVECs

2020 ◽  
Vol 14 (08) ◽  
pp. 908-917
Author(s):  
Wencheng He ◽  
Lei Huang ◽  
Hua Luo ◽  
Yang Zang ◽  
Youzhong An ◽  
...  

Introduction: Hypocalcemia has been widely recognized in sepsis patients. However, the cause of hypocalcemia in sepsis is still not clear, and little is known about the subcellular distribution of Ca2+ in tissues during sepsis. Methodology: We measured the dynamic change in Ca2+ levels in body fluid and subcellular compartments, including the cytosol, endoplasmic reticulum and mitochondria, in major organs of cecal ligation and puncture (CLP)-operated rats, as well as the subcellular Ca2+ flux in HUVECs which treated by endotoxin and cytokines. Results: In the model of CLP-induced sepsis, the blood and urinary Ca2+ concentrations decreased rapidly, while the Ca2+ concentration in ascites fluid increased. The Ca2+ concentrations in the cytosol, ER, and mitochondria were elevated nearly synchronously in major organs in our sepsis model. Moreover, the calcium overload in CLP-operated rats treated with calcium supplementation was more severe than that in the non-calcium-supplemented rats but was alleviated by treatment with the calcium channel blocker verapamil. Similar subcellular Ca2+ flux was found in vitro in HUVECs and was triggered by lipopolysaccharide (LPS)/TNF-α. Conclusions: Ca2+ influx from the blood into the intercellular space and Ca2+ release into ascites fluid may cause hypocalcemia in sepsis and that this process may be due to the synergistic effect of endotoxin and cytokines.

2012 ◽  
Vol 303 (10) ◽  
pp. F1443-F1453 ◽  
Author(s):  
Chung-Hsi Hsing ◽  
Chiou-Feng Lin ◽  
Edmund So ◽  
Ding-Ping Sun ◽  
Tai-Chi Chen ◽  
...  

Bone morphogenetic protein (BMP)-7 protects sepsis-induced acute kidney injury (AKI). Dexmedetomidine (DEX), an α2-adrenoceptor (α2-AR) agonist, has anti-inflammatory effects. We investigated the protective effects of DEX on sepsis-induced AKI and the expression of BMP-7 and histone deacetylases (HDACs). In vitro , the effects of DEX or trichostatin A (TSA, an HDAC inhibitor) on TNF-α, monocyte chemotactic protein (MCP-1), BMP-7, and HDAC mRNA expression in LPS-stimulated rat renal tubular epithelial NRK52E cells, was determined using real-time PCR. In vivo, mice were intraperitoneally injected with DEX (25 μg/kg) or saline immediately and 12 h after cecal ligation and puncture (CLP) surgery. Twenty-four hours after CLP, we examined kidney injury and renal TNF-α, MCP-1, BMP-7, and HDAC expression. Survival was monitored for 120 h. LPS increased HDAC2, HDAC5, TNF-α, and MCP-1 expression, but decreased BMP-7 expression in NRK52E cells. DEX treatment decreased the HDAC2, HDAC5, TNF-α, and MCP-1 expression, but increased BMP-7 and acetyl histone H3 expression, whose effects were blocked by yohimbine, an α2-AR antagonist. With DEX treatment, the LPS-induced TNF-α expression and cell death were attenuated in scRNAi-NRK52E but not BMP-7 RNAi-NRK52E cells. In CLP mice, DEX treatment increased survival and attenuated AKI. The expression of HDAC2, HDAC5, TNF-α, and MCP-1 mRNA in the kidneys of CLP mice was increased, but BMP-7 was decreased. However, DEX treatment reduced those changes. DEX reduces sepsis-induced AKI by decreasing TNF-α and MCP-1 and increasing BMP-7, which is associated with decreasing HDAC2 and HDAC5, as well as increasing acetyl histone H3.


2019 ◽  
Vol 25 (4) ◽  
pp. 235-243 ◽  
Author(s):  
Pengfei Li ◽  
Ran Zhao ◽  
Kevin Fan ◽  
Stephen Iwanowycz ◽  
Hongkuan Fan ◽  
...  

Dendritic cells (DCs) are professional Ag-presenting cells that play a critical role in both innate and adaptive immune responses. DCs recognize and respond to bacteria through multiple PRRs, including TLRs. Heat shock protein gp96/grp94 is a master essential chaperone for TLRs in the endoplasmic reticulum. We generated DC-specific gp96-knockout (KO) mice and showed that gp96 KO DCs were unable to respond to multiple TLR ligands. TLR-mediated hyperinflammatory response can lead to sepsis. However, the roles of neither DCs nor the DC-intrinsic gp96 in the process are completely understood. In a LPS-induced sepsis model, we hereby found that deletion of gp96 in DCs significantly reduced serum TNF-α levels and improved survival. Furthermore, using the well-defined polymicrobial sepsis model of cecal ligation and puncture, we found that DC-specific ablation of gp96 improved survival with significantly attenuated liver and renal injuries, decreased circulating inflammatory cytokines, altered DC maturation and activation, and increased serum Ig. Collectively, we demonstrate that deletion of gp96 in DCs is beneficial in protecting mice against sepsis induced by both endotoxemia and polymicrobial infections. We conclude that targeting gp96 in DCs may provide a potential novel approach for reducing the morbidity and mortality of sepsis.


2020 ◽  
Vol 19 (4) ◽  
pp. 715-720
Author(s):  
XiaoBo Wang ◽  
JianHua Wu ◽  
BuKao Ni

Purpose: To investigate the protective effects of 4, 5-O-dicaffeoylquinic acid (DCQA) isolated from Xanthium sibiricum Patr. against mouse sepsis caused by cecal ligation/puncture (CLP) in vivo, as well as the molecular mechanisms of action involved.Methods: DCQA (7.5, 15, and 30 mg/kg/day) were administered to the mice with sepsis and the survival rate was obtained. Tumor necrosis factor (TNF)-α and interleukin (IL)-6 were examined by enzyme-linked immunosorbent assay (ELISA). Subsequently, the lipopolysaccharide (LPS) neutralizing ability of DCQA (2, 4, and 8 μg/mL) was measured using limulus amebocyte lysate (LAL) test in vitro. Furthermore, the effect of DCQA (10, 20, and 40 μg/mL) on mRNA expression of TNF-α, IL-6, and IL-8 in LPS (100 ng/mL)-treated RAW 264.7 cells was assessed using quantitative real time-polymerase chain reaction (RT-qPCR) assay.Results: DCQA significantly improved the survival rate of mice with sepsis caused by CLP (35, 50, and 65 %, respectively vs. 15 % for control, p < 0.05). LPS levels fell on co-incubation with DCQA in vitro. Moreover, ELISA and RT-qPCR results revealed that DCQA treatment lowered tendency in the mRNA expression of TNF-α, IL-6, and IL-8 (p < 0.01).Conclusion: DCQA exhibits protective effects against sepsis in mice mediated by downregulating TNF-α, IL-6, and IL-8. Further studies, in animals and humans are requied to determine the safety and efficacy of DCQA in both animal and clinical management of sepsis. Keywords: Xanthium sibiricum, 4,5-O-Dicaffeoylquinic acid, Sepsis, Cecal ligation and puncture, Lipopolysaccharide, TNF-α, IL-6, IL-8


2018 ◽  
Vol 38 (2) ◽  
Author(s):  
Yulong Yao ◽  
Fangyuan Sun ◽  
Ming Lei

To investigate the regulatory mechanism of miR-25 in sepsis-induced cardiomyocyte apoptosis. Rats models of sepsis were established by cecal ligation and puncture (CLP). Lipopolysaccharide (LPS)-induced cardiomyocyte was used as an in vitro model of sepsis. The expressions of miR-25, tensin homolog deleted on chromosome 10 (PTEN), Toll-like receptors 4 (TLR4), and p-p65 were analyzed by quantitative real-time PCR (qRT-PCR) and Western blot, respectively. The levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected by ELISA. Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated d-UTP nick end labeling (TUNEL) assay. The relationship between miR-25 and PTEN was measured by luciferase reporter assays. MiR-25 expression in serum of CLP rats and LPS-induced cardiomyocyte was decreased, while the contents of TNF-α and IL-6 were increased. Moreover, the expressions of PTEN, TLR4, and p-p65 in LPS-induced cardiomyocyte were significantly increased. Overexpression of miR-25 increased the survival rate of rats, inhibited LPS-increased cardiomyocyte apoptosis, reversed the increased expression of PTEN, TLR4, p-p65, TNF-α, and IL-6 induced by LPS. The luciferase assay demonstrated that PTEN was a target of miR-25. Additionally, pcDNA-PTEN reversed the inhibitory effect of miR-25 mimic on cardiomyocyte apoptosis, while TAK-242 (TLR-4 inhibitor) countered this effect. miR-25 reduced LPS-induced cardiomyocyte apoptosis by down-regulating PTEN/TLR4/NF-κB axis.


2022 ◽  
Vol 8 (1) ◽  
Author(s):  
Xiaoyan Wang ◽  
Danyong Liu ◽  
XiHe Zhang ◽  
LiuMing Yang ◽  
Zhengyuan Xia ◽  
...  

AbstractAcute lung injury (ALI) represents a frequent sepsis-induced inflammatory disorder. Mesenchymal stromal cells (MSCs) elicit anti-inflammatory effects in sepsis. This study investigated the mechanism of exosomes from adipose-derived MSCs (ADMSCs) in sepsis-induced ALI. The IL-27r−/− (WSX-1 knockout) or wild-type mouse model of sepsis was established by cecal ligation and puncture (CLP). The model mice and lipopolysaccharide (LPS)-induced macrophages were treated with ADMSC-exosomes. The content of Dil-labeled exosomes in pulmonary macrophages, macrophages CD68+ F4/80+ in whole lung tissues, and IL-27 content in macrophages were detected. The mRNA expression and protein level of IL27 subunits P28 and EBI3 in lung tissue and the levels of IL-6, TNF-α, and IL-1β were measured. The pulmonary edema, tissue injury, and pulmonary vascular leakage were measured. In vitro, macrophages internalized ADMSC-exosomes, and ADMSC-exosomes inhibited IL-27 secretion in LPS-induced macrophages. In vivo, IL-27 knockout attenuated CLP-induced ALI. ADMSC-exosomes suppressed macrophage aggregation in lung tissues and inhibited IL-27 secretion. ADMSC-exosomes decreased the contents of IL-6, TNF-α, and IL-1β, reduced pulmonary edema and pulmonary vascular leakage, and improved the survival rate of mice. Injection of recombinant IL-27 reversed the protective effect of ADMSC-exosomes on sepsis mice. Collectively, ADMSC-exosomes inhibited IL-27 secretion in macrophages and alleviated sepsis-induced ALI in mice.


2000 ◽  
Vol 68 (11) ◽  
pp. 6108-6114 ◽  
Author(s):  
M. L. Steinhauser ◽  
C. M. Hogaboam ◽  
A. Matsukawa ◽  
N. W. Lukacs ◽  
R. M. Strieter ◽  
...  

ABSTRACT Previous studies have suggested that the C-C chemokine C10 is involved in the chronic stages of host defense reactions. The present study addressed the role of C10 in a murine model of septic peritonitis, induced by cecal ligation and puncture (CLP). Unlike other C-C chemokines, C10 levels in the peritoneal wash were increased approximately 30-fold above baseline levels at 48 h after CLP surgery. Immunoneutralization of peritoneal C10 levels with polyclonal anti-C10 antiserum during CLP-induced peritonitis negatively impacted mouse survival over 4 days. In contrast, when 500 ng of recombinant murine C10 was administered immediately after CLP surgery, the 4-day survival rate increased from 20% to over 60%. The C10 therapy appeared to facilitate a rapid and significant enhancement of the levels of tumor necrosis factor alpha (TNF-α) and monocyte chemoattractant protein-1 (MCP-1) and a later increase in interleukin-13 (IL-13) levels in the peritoneal cavity. In vitro studies showed that the combination of IL-1β and C10 markedly augmented TNF-α synthesis by peritoneal macrophages and that C10 synthesis was induced in these cells following their exposure to IL-13. At 24 h after CLP surgery, only 25% of C10-treated mice were bacteremic versus 85% of the control group that exhibited dissemination of bacteria into the circulation. The lack of bacteremia in C10-treated mice appeared to be related, in part, to in vitro evidence that C10 significantly enhanced the bacterial phagocytic activity of peritoneal macrophages. In addition, in vivo evidence suggested that C10 therapy significantly reduced the amount of material that leaked from the damaged gut. Taken together, the results of this study demonstrate that the C10 chemokine rapidly promotes disease resolution in the CLP model through its direct effects on the cellular events critically involved in host defense during septic peritonitis.


2021 ◽  
Vol 3 (2) ◽  
pp. 97-106
Author(s):  
Arezou Khosrojerdi ◽  
◽  
Sara Soudi ◽  
Ahmad Zavaran Hosseini ◽  
Seyed Mahmoud Hashemi ◽  
...  

Background: Sepsis is a systemic inflammatory disease in response to the pathogens that leads to vital organ failures the failure of vital organs. Appropriate animal models should be developed to measure the effectiveness of therapeutic methods. Cecal Ligation and Puncture (CLP) is the most widely used methods of creating the sepsis model. Some variables interfere in the creation of the CLP model which terminated to result in an unrepeatable dynamic of the inflammatory responses. The current research, suggests presents the simultaneous study of inflammatory responses in serum and liver as a criterion for determining the inflammatory status of the CLP model. Materials and Methods: CLP model was induced in 15 female C57bl/6 mice. IL-6, TNF-α, IL-10, and TGF-β1 cytokines levels were measured at 24, 48, and 72 hours after CLP induction in both serum and liver tissue by ELISA method. Serum levels of liver enzymes were analyzed by the clinical chemistry analyzer. All studies were performed in healthy mice as well. The results were reported as Mean±SD. Results: The levels of IL-10 and TGF- β1 in the liver is were significantly (P≤0.05) higher than serum. The production of IL-10 and TGF- β1 in the serum and liver reaches its maximum at peaked 24 and 72 hours after CLP induction. The level of TNF-α in the liver is was significantly (P≤0.05) higher than serum with a maximum production 24 hours after CLP induction. Conclusion: Serum is not a good representative of the inflammatory condition in sepsis. Therefore, it is suggested that local inflammatory responses be considered in evaluating the model, and the determination of drug efficacy.


2021 ◽  
Vol 27 (1) ◽  
Author(s):  
William Royster ◽  
Hui Jin ◽  
Ping Wang ◽  
Monowar Aziz

Abstract Background Sepsis is a life-threatening disease syndrome caused by a dysregulated host response to infection and injury. Extracellular cold-inducible RNA-binding protein (eCIRP) acts as a damage-associated molecular pattern. Peritoneal cavity (PerC) B-1a cells attenuate inflammation and tissue injury by spontaneous releasing natural IgM and IL-10. Sialic acid-binding immunoglobulin-type lectin-G (Siglec-G) is a CD33-related receptor highly expressed in B-1a cells to serve critical immunoregulatory functions. In sepsis, B-1a cell numbers in PerC are decreased. We hypothesized that eCIRP causes the reduction of PerC B-1a cells and alters their function during sepsis. Methods Sepsis was induced in WT and CIRP−/− mice by cecal ligation and puncture (CLP). PerC washout cells were collected and B-1a cells and Siglec-G were assessed by flow cytometry. Mice were i.p. injected with recombinant murine (rm) CIRP and after 20 h, Siglec-G expression in PerC B-1a cells were assessed. PerC B-1a cells were treated with rmCIRP for 4 h and Siglec-G expression was assessed. PerC B-1a cells were pre-treated with anti-Siglec-G Ab and then after stimulated with rmCIRP for 24 h, IL-6 levels in the culture supernatants were assessed. Results eCIRP levels in the PerC were elevated in septic mice. In WT mice, the frequencies and numbers of total and Siglec-G+ B-1a cells in the PerC were significantly decreased in the CLP group compared to sham group, whereas in CIRP−/− mice, their frequencies and numbers in sepsis were significantly rescued compared to WT septic mice. Mice injected with rmCIRP showed decreased frequencies and numbers of total and Siglec-G+ PerC B-1a cells compared to PBS-injected mice. In vitro treatment of PerC B-1a cells with rmCIRP demonstrated significant reduction in Siglec-G mRNA and protein compared to PBS group. PerC B-1a cells treated with anti-Siglec-G Ab had significantly higher production of IL-6 in response to rmCIRP compared to IgG control. Anti-Siglec-G Ab treated B-1a cells co-cultured with macrophages produced significantly higher levels of IL-6, and TNF-α, and lower levels of IL-10 compared to IgG-treated B-1a cells and macrophage co-cultures stimulated with rmCIRP. Conclusion eCIRP reduces PerC B-1a cell pool and skews them to a pro-inflammatory phenotype by downregulating Siglec-G expression. Targeting eCIRP will retain Siglec-G expressing B-1a cells in the PerC and preserve their anti-inflammatory function in sepsis.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Kun-Ta Chou ◽  
Shih-Chin Cheng ◽  
Shiang-Fen Huang ◽  
Diahn-Warng Perng ◽  
Shi-Chuan Chang ◽  
...  

Abstract Sleep apnea has been associated with a variety of diseases, but its impact on sepsis outcome remains unclear. This study investigated the effect of intermittent hypoxia [IH]–the principal feature of sleep apnea–on murine sepsis. 5-week-old male C57BL6 mice were assigned to groups receiving severe IH (O2 fluctuating from room air to an O2 nadir of 5.7% with a cycle length of 90 seconds), mild IH (room air to 12%, 4 minutes/cycle), or room air for 3 weeks. Sepsis was induced by cecal ligation and puncture and survival was monitored. Sepsis severity was evaluated by murine sepsis scores, blood bacterial load, plasma tumor necrosis factor-α [TNF-α]/interleukin-6 [IL-6] levels and histopathology of vital organs. Compared with normoxic controls, mice subjected to severe IH had earlier mortality, a lower leukocyte count, higher blood bacterial load, higher plasma TNF-α and IL-6 levels, more severe inflammatory changes in the lung, spleen and small intestine. Mice subjected to mild IH did not differ from normoxic controls, except a higher IL-6 level after sepsis induced. The adverse impact of severe IH was reversed following a 10-day normoxic recovery. In conclusion, severe IH, not mild IH, contributed to poorer outcomes in a murine sepsis model.


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