scholarly journals TheERK1/2Inhibitor U0126 Attenuates Diabetes-Induced Upregulation of MMP-9 and Biomarkers of Inflammation in the Retina

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Ghulam Mohammad ◽  
Mohammad Mairaj Siddiquei ◽  
Mohammad Imtiaz Nawaz ◽  
Ahmed M. Abu El-Asrar

This study was conducted to determine the expression of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in a time-dependent manner and the effect of extracellular-signal-regulated kinases-1/2 (ERK1/2) inhibition on the expressions of MMP-9, TIMP-1, and inflammatory biomarkers in the retinas of diabetic rats. The expression of MMP-9 was quantified by zymography, and the mRNA level of MMP-9 and TIMP-1 was quantified by RT-PCR. The expression of inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) was examined by Western blot analysis. MMP-9 expression was significantly higher in diabetic rat retinas compared to controls at all time points.TIMP-1 expression was nonsignificantly upregulated at 1week of diabetes and was significantly downregulated at 4 and 12 weeks of diabetes. Intravitreal administration of the ERK1/2inhibitor U0126 prior to induction of diabetes decreased ERK1/2activation, attenuated diabetes-induced upregulation of MMP-9, iNOS, IL-6, and TNF-αand upregulated TIMP-1 expression. In MMP-9 knockout mice, diabetes had no effect on retinal iNOS expression and its level remained unchanged. These data provide evidence that ERK1/2signaling pathway is involved in MMP-9, iNOS, IL-6, and TNF-αinduction in diabetic retinas and suggest that ERK1/2can be a novel therapeutic target in diabetic retinopathy.

1999 ◽  
Vol 43 (11) ◽  
pp. 2787-2789 ◽  
Author(s):  
Kazuhiko Sassa ◽  
Yutaka Mizushima ◽  
Masashi Kobayashi

ABSTRACT In vitro treatment with clarithromycin inhibited the expression of the matrix metalloproteinase-9, transforming growth factor β, and tumor necrosis factor alpha genes in 13762NF rat mammary adenocarcinoma cells. Transient enhancement, rather than inhibition, was observed for the interleukin-6 gene, and no significant change was observed for the tissue inhibitor of metalloproteinase-2 gene. Such an effect was not observed for cefotiam or gentamicin.


2020 ◽  
Vol 48 (4) ◽  
pp. 030006052091959
Author(s):  
Guobing Chen ◽  
Dandan Ge ◽  
Bizhen Zhu ◽  
Huixuan Shi ◽  
Qilin Ma

Objective This study aimed to examine the changes and significance of matrix metalloproteinase 9 (MMP9), MMP2, tissue inhibitor of metalloproteinase 1 (TIMP1), and TIMP2 in rats with lipopolysaccharide (LPS)-induced acute lung injury (ALI). Methods Wistar rats were randomly divided into a control group (injected with saline) and an ALI group (injected with LPS), then subdivided into four time points (2, 6, 12, and 24 hours). Serum tumor necrosis factor alpha and interleukin-6 levels were detected by ELISA to investigate the inflammatory reaction after LPS injection. The degree of ALI was determined by hematoxylin–eosin staining of lung tissue, the lung wet/dry weight ratio, and pulmonary permeability index. Changes in lung MMP and TIMP protein and mRNA levels were detected by western blotting and quantitative real-time polymerase chain reaction. Results Changes in the ratios of MMP9/TIMP1 and MMP2/TIMP2 were consistent with and strongly positively associated with the lung wet/dry weight ratio, the pulmonary permeability index, and serum tumor necrosis factor alpha and interleukin-6 levels in the ALI group. Conclusion ALI induced by LPS may be related to upregulation of MMP9/TIMP1 and MMP2/TIMP2 ratios.


2021 ◽  
Vol 22 (9) ◽  
pp. 4350
Author(s):  
Hyunjin Yeo ◽  
Younghan Lee ◽  
Sungshin Ahn ◽  
Euitaek Jung ◽  
Yoongho Lim ◽  
...  

Thymic stromal lymphopoietin (TSLP) is an epithelial cell-derived cytokine that acts as a critical mediator in the pathogenesis of atopic dermatitis (AD). Various therapeutic agents that prevent TSLP function can efficiently relieve the clinical symptoms of AD. However, the downregulation of TSLP expression by therapeutic agents remains poorly understood. In this study, we investigated the mode of action of chrysin in TSLP suppression in an AD-like inflammatory environment. We observed that the transcription factor early growth response (EGR1) contributed to the tumor necrosis factor alpha (TNFα)-induced transcription of TSLP. Chrysin attenuated TNFα-induced TSLP expression by downregulating EGR1 expression in HaCaT keratinocytes. We also showed that the oral administration of chrysin improved AD-like skin lesions in the ear and neck of BALB/c mice challenged with 2,4-dinitrochlorobenzene. We also showed that chrysin suppressed the expression of EGR1 and TSLP by inhibiting the extracellular signal-regulated kinase (ERK) 1/2 and c-Jun N-terminal kinase (JNK) 1/2 mitogen-activated protein kinase pathways. Collectively, the findings of this study suggest that chrysin improves AD-like skin lesions, at least in part, through the downregulation of the ERK1/2 or JNK1/2-EGR1-TSLP signaling axis in keratinocytes.


2009 ◽  
Vol 77 (9) ◽  
pp. 3686-3695 ◽  
Author(s):  
Hany M. Ibrahim ◽  
Hiroshi Bannai ◽  
Xuenan Xuan ◽  
Yoshifumi Nishikawa

ABSTRACT Toxoplasma gondii modulates pro- and anti-inflammatory responses to regulate parasite multiplication and host survival. Pressure from the immune response causes the conversion of tachyzoites into slowly dividing bradyzoites. The regulatory mechanisms involved in this switch are poorly understood. The aim of this study was to investigate the immunomodulatory role of T. gondii cyclophilin 18 (TgCyp18) in macrophages and the consequences of the cellular responses on the conversion machinery. Recombinant TgCyp18 induced the production of nitric oxide (NO), interleukin-12 (IL-12), and tumor necrosis factor alpha through its binding with cysteine-cysteine chemokine receptor 5 (CCR5) and the production of gamma interferon and IL-6 in a CCR5-independent manner. Interestingly, the treatment of macrophages with TgCyp18 resulted in the inhibition of parasite growth and an enhancement of the conversion into bradyzoites via NO in a CCR5-dependent manner. In conclusion, T. gondii possesses sophisticated mechanisms to manipulate host cell responses in a TgCyp18-mediated process.


1990 ◽  
Vol 172 (6) ◽  
pp. 1843-1852 ◽  
Author(s):  
P A Marsden ◽  
B J Ballermann

Endothelium-derived nitric oxide (NO) causes vasodilatation by activating soluble guanylate cyclase, and glomerular mesangial cells respond to NO with elevations of intracellular guanosine 3',5'-cyclic monophosphate (cGMP). We explored whether mesangial cells can be stimulated to produce NO and whether NO modulates mesangial cell function in an autocrine or paracrine fashion. Tumor necrosis factor alpha (TNF-alpha) raised mesangial cell cGMP levels in a time- and concentration-dependent manner (threshold dose 1 ng/ml, IC50 13.8 ng/ml, maximal response 100 ng/ml). TNF-alpha-induced increases in mesangial cGMP content were evident at 8 h and maximal at 18-24 h. The TNF-alpha-induced stimulation of mesangial cell cGMP production was abrogated by actinomycin D or cycloheximide suggesting dependence on new RNA or protein synthesis. Hemoglobin and methylene blue, both known to inhibit NO action, dramatically reduced TNF-alpha-induced mesangial cell cGMP production. Superoxide dismutase, known to potentiate NO action, augmented the TNF-alpha-induced effect. Ng-monomethyl-L-arginine (L-NMMA) decreased cGMP levels in TNF-alpha-treated, but not vehicle-treated mesangial cells in a concentration-dependent manner (IC50 53 microM). L-arginine had no effect on cGMP levels in control or TNF-alpha-treated mesangial cells but reversed L-NMMA-induced inhibition. Interleukin 1 beta and lipopolysaccharide (LPS), but not interferon gamma, also increased mesangial cell cGMP content. Transforming growth factor beta 1 blunted the mesangial cell response to TNF-alpha. TNF-alpha-induced L-arginine-dependent increases in cGMP were also evident in bovine renal artery vascular smooth muscle cells, COS-1 cells, and 1502 human fibroblasts. These findings suggest that TNF-alpha induces expression in mesangial cell of an enzyme(s) involved in the formation of L-arginine-derived NO. Moreover, the data indicate that NO acts in an autocrine and paracrine fashion to activate mesangial cell soluble guanylate cyclase. Cytokine-induced formation of NO in mesangial and vascular smooth muscle cells may be implicated in the pathogenesis of septic shock.


2016 ◽  
Vol 94 (4) ◽  
pp. 408-415 ◽  
Author(s):  
Xiaoyuan Han ◽  
Sonali Shaligram ◽  
Rui Zhang ◽  
Leigh Anderson ◽  
Roshanak Rahimian

Hyperglycemia affects male and female vascular beds differently. We have previously shown that 1 week after the induction of diabetes with streptozotocin (STZ), male and female rats exhibit differences in aortic endothelial function. To examine this phenomenon further, aortic responses were studied in male and female rats 8 weeks after the induction of diabetes (intermediate stage). Endothelium-dependent vasodilation (EDV) to acetylcholine (ACh) was measured in phenylephrine (PE) pre-contracted rat aortic rings. Concentration response curves to PE were generated before and after L-NAME, a nitric oxide synthase (NOS) inhibitor. Furthermore, mRNA expression of endothelial nitric oxide synthase (eNOS) and NADPH oxidase subunit (Nox1) were determined. At 8 weeks, diabetes impaired EDV to a greater extent in female than male aortae. Furthermore, the responsiveness to PE was significantly enhanced only in female diabetic rats, and basal NO, as indicated by the potentiation of the response to PE after L-NAME, was reduced in female diabetic rat aortae to the same levels as in males. In addition, eNOS mRNA expression was decreased, while the Nox1 expression was significantly enhanced in diabetic female rats. These results suggest that aortic function in female diabetic rats after 8 weeks exhibits a more prominent impairment and that NO may be involved.


1997 ◽  
Vol 17 (10) ◽  
pp. 5719-5726 ◽  
Author(s):  
J Alonso ◽  
L Sánchez de Miguel ◽  
M Montón ◽  
S Casado ◽  
A López-Farré

Changes in endothelial nitric oxide synthase (eNOS) expression may be involved in the endothelium-dependent vasorelaxation dysfunction associated with several vascular diseases. In the present work, we demonstrate that eNOS mRNA contains a previously undescribed cis element in the 3' untranslated region (3' UTR). A U+C-rich segment in the 3' UTR is critical in complex formation with bovine aortic endothelial cell cytosolic proteins. Tumor necrosis factor alpha (TNF-alpha), which destabilizes eNOS mRNA, increased the binding activity of the cytosolic proteins in a time-dependent manner. These data suggest that endothelial cytosolic proteins bind to the 3' UTR of eNOS mRNA. These proteins may play a role in TNF-alpha-induced eNOS mRNA destabilization.


2018 ◽  
Vol 86 (6) ◽  
Author(s):  
Janette M. Shank ◽  
Brittni R. Kelley ◽  
Joseph W. Jackson ◽  
Jessica L. Tweedie ◽  
Dana Franklin ◽  
...  

ABSTRACTCampylobacter jejuniis a leading cause of bacterially derived gastroenteritis worldwide.Campylobacteris most commonly acquired through the consumption of undercooked poultry meat or through drinking contaminated water. Following ingestion,Campylobacteradheres to the intestinal epithelium and mucus layer, causing toxin-mediated inflammation and inhibition of fluid reabsorption. Currently, the human response to infection is relatively unknown, and animal hosts that model these responses are rare. As such, we examined patient fecal samples for the accumulation of the neutrophil protein calgranulin C during infection withCampylobacter jejuni. In response to infection, calgranulin C was significantly increased in the feces of humans. To determine whether calgranulin C accumulation occurs in an animal model, we examined disease in ferrets. Ferrets were effectively infected byC. jejuni, with peak fecal loads observed at day 3 postinfection and full resolution by day 12. Serum levels of interleukin-10 (IL-10) and tumor necrosis factor alpha (TNF-α) significantly increased in response to infection, which resulted in leukocyte trafficking to the colon. As a result, calgranulin C increased in the feces of ferrets at the time whenC. jejuniloads decreased. Further, the addition of purified calgranulin C toC. jejunicultures was found to inhibit growth in a zinc-dependent manner. These results suggest that upon infection withC. jejuni, leukocytes trafficked to the intestine release calgranulin C as a mechanism for inhibitingC. jejunigrowth.


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