scholarly journals A32 EMPAGLIFOZIN IMPROVES GASTROINTESTINAL INFLAMMATION IN A MOUSE MODEL OF COLITIS

2021 ◽  
Vol 4 (Supplement_1) ◽  
pp. 213-215
Author(s):  
K Madsen ◽  
H Dang ◽  
N Hotte ◽  
V Mocanu ◽  
M Ferdaoussi ◽  
...  

Abstract Background Empagliflozin (EMPA) is a highly selective sodium glucose cotransporter-2 (SGLT2) inhibitor and is increasingly being utilized as an antihyperglycemic agent in the management of type 2 diabetes. Interestingly, it has been demonstrated in human trials that EMPA treatment exerts potent cardioprotective effects by reducing cardiac inflammation independently of glycemic control. Further, EMPA has also been shown to suppress LPS-induced renal and systemic inflammation in an animal model. Based on these findings, we hypothesized that EMPA treatment may also be effective in reducing gut inflammation. Aims The aim of this study was to examine the effects of treatment with EMPA on gastrointestinal inflammation in an animal model of inflammatory bowel disease and to determine mechanistic insights regarding its direct effects on gut cytokine secretion. Methods Adult male and female IL-10-/- mice with established colitis were treated with a daily gavage of EMPA (10mg/kg; n=10) or vehicle (n=10) for 14 days. Disease activity was assessed by measurement of mouse weight, colonic weight and length, histological score, cytokine levels in colonic homogenate and lipocalin-2 levels in stool. To examine for possible direct effects of EMPA, colonic explants from wild-type (n=8) and IL-10-/- (n=8) mice were incubated with increasing doses of EMPA (0.1–5 µM) ± LPS (10µg/ml) for 2 hours and tissue levels of IL-1β and TNFα protein measured by ELISA. Results After 14 days EMPA treated IL-10-/- mice had a significant improvement in colonic inflammation as evidenced by decreased colonic weight to length ratio (p=0.019), decreased fecal lipocalin-2 (p=0.03), as well as decreased enterocyte injury (p=0.01), decreased lamina propria neutrophils (p=0.01) and decreased total histological score (p=0.006). EMPA treated mice also maintained their weight over the 14 days while untreated mice continued to lose weight (p=0.04). There were no significant differences in colonic homogenate levels of TNFα, IL-1β, or IL-6 or in blood glucose levels between EMPA-treated mice and controls. In addition, EMPA did not suppress levels of basal or LPS-induced TNFα and IL-1β in colonic explants from either wild-type or IL-10-/- mice suggesting that the beneficial effects in IL-10-/- mice were not due to direct effects of EMPA on colonic TNFα or IL-1β cytokine levels. Conclusions EMPA treatment dramatically improved histologic and fecal inflammatory markers and maintained body weight in adult IL-10-/- mice with established colitis. These findings suggest further investigations into the effects of EMPA in treating gut inflammation are warranted. Funding Agencies CAG, CIHR

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lidan Liu ◽  
Chaim Z. Aron ◽  
Cullen M. Grable ◽  
Adrian Robles ◽  
Xiangli Liu ◽  
...  

AbstractLevels of intestinal toll-like receptor 4 (TLR4) impact inflammation in the neonatal gastrointestinal tract. While surfactant protein A (SP-A) is known to regulate TLR4 in the lung, it also reduces intestinal damage, TLR4 and inflammation in an experimental model of necrotizing enterocolitis (NEC) in neonatal rats. We hypothesized that SP-A-deficient (SP-A−/−) mice have increased ileal TLR4 and inflammatory cytokine levels compared to wild type mice, impacting intestinal physiology. We found that ileal TLR4 and proinflammatory cytokine levels were significantly higher in infant SP-A−/− mice compared to wild type mice. Gavage of neonatal SP-A−/− mice with purified SP-A reduced ileal TLR4 protein levels. SP-A reduced expression of TLR4 and proinflammatory cytokines in normal human intestinal epithelial cells (FHs74int), suggesting a direct effect. However, incubation of gastrointestinal cell lines with proteasome inhibitors did not abrogate the effect of SP-A on TLR4 protein levels, suggesting that proteasomal degradation is not involved. In a mouse model of experimental NEC, SP-A−/− mice were more susceptible to intestinal stress resembling NEC, while gavage with SP-A significantly decreased ileal damage, TLR4 and proinflammatory cytokine mRNA levels. Our data suggests that SP-A has an extrapulmonary role in the intestinal health of neonatal mice by modulating TLR4 and proinflammatory cytokines mRNA expression in intestinal epithelium.


Endocrinology ◽  
2008 ◽  
Vol 149 (8) ◽  
pp. 4080-4085 ◽  
Author(s):  
Maria Pini ◽  
Melissa E. Gove ◽  
Joseph A. Sennello ◽  
Jantine W. P. M. van Baal ◽  
Lawrence Chan ◽  
...  

Adipokines, cytokines mainly produced by adipocytes, are active participants in the regulation of inflammation. Administration of zymosan (ZY) was used to investigate the regulation and role of adipokines during peritonitis in mice. Injection of ZY led to a significant increase in leptin levels in both serum and peritoneal lavage fluid, whereas a differential trend in local vs. systemic levels was observed for both resistin and adiponectin. The role of leptin in ZY-induced peritonitis was investigated using leptin-deficient ob/ob mice, with and without reconstitution with exogenous leptin. Leptin deficiency was associated with delayed resolution of peritoneal inflammation induced by ZY, because ob/ob mice had a more pronounced cellular infiltrate in the peritoneum as well as higher and prolonged local and systemic levels of IL-6, TNFα, IL-10, and chemokine (C-X-C motif) ligand 2 compared with wild-type mice. Reconstitution with exogenous leptin exacerbated the inflammatory infiltrate and systemic IL-6 levels in ob/ob mice while inhibiting production of TNFα, IL-10, and chemokine (C-X-C motif) ligand 2. In contrast with the important role of leptin in regulating each aspect of ZY-induced peritonitis, adiponectin deficiency was associated only with a decreased inflammatory infiltrate, without affecting cytokine levels. These findings point to a complex role for adipokines in ZY-induced peritonitis and further emphasize the interplay between obesity and inflammation.


2020 ◽  
Vol 4 (11) ◽  
Author(s):  
Katherine M Ranard ◽  
Matthew J Kuchan ◽  
John W Erdman

ABSTRACT Studying vitamin E [α-tocopherol (α-T)] metabolism and function in the brain and other tissues requires an animal model with low α-T status, such as the transgenic α-T transfer protein (Ttpa)–null (Ttpa−/−) mouse model. Ttpa+/− dams can be used to produce Ttpa−/− and Ttpa+/+mice for these studies. However, the α-T content in Ttpa+/− dams’ diet requires optimization; diets must provide sufficient α-T for reproduction, while minimizing the transfer of α-T to the offspring destined for future studies that require low baseline α-T status. The goal of this work was to assess the effectiveness and feasibility of 2 breeding diet strategies on reproduction outcomes and offspring brain α-T concentrations. These findings will help standardize the breeding methodology used to generate the Ttpa−/− mice for neurological studies.


Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1895
Author(s):  
Azra Memon ◽  
Bae Yong Kim ◽  
Se-eun Kim ◽  
Yuliya Pyao ◽  
Yeong-Geun Lee ◽  
...  

Background: Phytoncide is known to have antimicrobial and anti-inflammatory properties. Purpose: This study was carried out to confirm the anti-inflammatory activity of two types of phytoncide extracts from pinecone waste. Methods: We made two types of animal models to evaluate the efficacy, an indomethacin-induced gastroenteritis rat model and a dextran sulfate sodium-induced colitis mouse model. Result: In the gastroenteritis experiment, the expression of induced-nitric oxide synthase (iNOS), a marker for inflammation, decreased in the phytoncide-supplemented groups, and gastric ulcer development was significantly inhibited (p < 0.05). In the colitis experiment, the shortening of the colon length and the iNOS expression were significantly suppressed in the phytoncide-supplemented group (p < 0.05). Conclusions: Through this study, we confirmed that phytoncide can directly inhibit inflammation in digestive organs. Although further research is needed, we conclude that phytoncide has potential anti-inflammatory properties in the digestive tract and can be developed as a functional agent.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Kumfu ◽  
S.C Chattipakorn ◽  
N Chattipakorn

Abstract Background Iron overload cardiomyopathy is a common cause of death in iron overload patients. L-type calcium channels (LTCC) and T-type calcium channels (TTCC) have been shown to play important roles for iron uptake into the heart under iron overload condition. Recently, cardiomyocytes which exposed to lipocalin-2 (LCN-2) have been shown to increase apoptosis due to excessive intracellular iron accumulation. However, the mechanistic roles of LCN-2 and LCN-2 receptor (LCN-2R) as iron transporters in cardiomyocytes under iron overload condition have never been investigated. Purpose We hypothesized that the LCN-2 and LCN-2R are alternate iron uptake pathways into cardiomyocytes under iron overload condition. Methods H9c2 cardiomyocytes were treated with either LCN-2 siRNA or LCN-2R siRNA for 72 hr or LTCC blocker (verapamil), TTCC blocker (TTA-P2), or iron chelator deferiprone (DFP) for 1 hr. After treatment, cells were exposed to ferric ammonium citrate (FAC, Fe3+) or FAC + 1mM ascorbic acid (Fe2+) at 200 μM for 48 hr. Intracellular iron level, cell viability, mitochondrial dynamics, mitophagy and apoptosis were determined. Results Both Fe2+ and Fe3+ treated groups showed significantly increased intracellular iron uptake, decreased cell viability, increased mitochondrial fission, mitophagy and apoptotic protein expression in cardiomyocytes. Under Fe2+ overload condition, treatments with LTCC blocker, TTCC blocker, and DFP could significantly decrease intracellular iron accumulation and increase cell viability via decreasing mitochondrial fission, mitophagy and cleaved caspase-3 (Figure), whereas both LCN-2 and LCN-2R siRNA treatment had no beneficial effects on these parameters. Under Fe3+ overload condition, treatment with LCN-2 siRNA, LCN-2R siRNA, and DFP showed beneficial effects on those parameters, whereas neither LTCC nor TTCC blocker provided these benefits (Figure 1). Conclusion Silencing of LCN-2 and LCN-2R increased cardiomyocyte viability via decreasing iron uptake, mitochondrial fission, mitophagy and apoptosis under Fe3+ iron overload condition. Meanwhile, treatment with calcium channel blockers improved cardiomyocytes viability via decreasing iron uptake, mitochondrial fission, mitophagy and apoptosis under Fe2+ iron overload condition. All of these findings suggested that LTCC and TTCC played important roles for Fe2+ uptake, whereas LCN-2 and LCN-2R were essential for Fe3+ uptake into the cardiomyocytes under iron overload conditions. Figure 1. Cell viability and apoptosis Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Thailand Research Fund and NSTDA Research Chair Grant (NC)


2021 ◽  
Vol 53 (3) ◽  
pp. 407-421
Author(s):  
Jaewoong Jang ◽  
Jaewon Song ◽  
Hyunji Lee ◽  
Inae Sim ◽  
Young V. Kwon ◽  
...  

AbstractEndotoxemia, a type of sepsis caused by gram-negative bacterial endotoxin [i.e., lipopolysaccharide (LPS)], is associated with manifestations such as cytokine storm; failure of multiple organs, including the liver; and a high mortality rate. We investigated the effect and mechanism of action of LGK974, a Wnt signaling inhibitor, in mice with LPS-induced endotoxemia, an animal model of sepsis. LGK974 significantly and dose-dependently increased the survival rate and reduced plasma cytokine levels in mice with LPS-induced endotoxemia. Transcriptome analysis of liver tissues revealed significant changes in the expression of genes associated with the Wnt pathway as well as cytokine and NF-κB signaling during endotoxemia. LGK974 treatment suppressed the activation of NF-κB signaling and cytokine expression as well as the Wnt/β-catenin pathway in the livers of endotoxemic mice. Coimmunoprecipitation of phospho-IκB and β-transducin repeat-containing protein (β-TrCP) was increased in the livers of endotoxemic mice but was reduced by LGK974 treatment. Moreover, LGK974 treatment decreased the coimmunoprecipitation and colocalization of β-catenin and NF-κB, which were elevated in the livers of endotoxemic mice. Our results reveal crosstalk between the Wnt/β-catenin and NF-κB pathways via interactions between β-TrCP and phospho-IκB and between β-catenin and NF-κB during endotoxemia. The results of this study strongly suggest that the crosstalk between the Wnt/β-catenin and NF-κB pathways contributes to the mutual activation of these two pathways during endotoxemia, which results in amplified cytokine production, liver damage and death, and that LGK974 suppresses this vicious amplification cycle by reducing the crosstalk between these two pathways.


2003 ◽  
Vol 284 (3) ◽  
pp. G525-G535 ◽  
Author(s):  
Christoph Schramm ◽  
Martina Protschka ◽  
Heinz H. Köhler ◽  
Jürgen Podlech ◽  
Matthias J. Reddehase ◽  
...  

In autoimmune hepatitis, strong TGF-β1 expression is found in the inflamed liver. TGF-β overexpression may be part of a regulatory immune response attempting to suppress autoreactive T cells. To test this hypothesis, we determined whether impairment of TGF-β signaling in T cells leads to increased susceptibility to experimental autoimmune hepatitis (EAH). Transgenic mice of strain FVB/N were generated expressing a dominant-negative TGF-β type II receptor in T cells under the control of the human CD2 promoter/locus control region. On induction of EAH, transgenic mice showed markedly increased portal and periportal leukocytic infiltrations with hepatocellular necroses compared with wild-type mice (median histological score = 1.8 ± 0.26 vs. 0.75 ± 0.09 in wild-type mice; P < 0.01). Increased IFN-γ production (118 vs. 45 ng/ml) and less IL-4 production (341 vs. 1,256 pg/ml) by mononuclear cells isolated from transgenic livers was seen. Impairment of TGF-β signaling in T cells therefore leads to increased susceptibility to EAH in mice. This suggests an important role for TGF-β in immune homeostasis in the liver and may teleologically explain TGF-β upregulation in response to T cell-mediated liver injury.


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