scholarly journals Fasting increases iron export by modulating ferroportin 1 expression through the Ghrelin/GHSR1α/MAPK pathway in the liver

2020 ◽  
Author(s):  
Qianqian Luo ◽  
Jianan Hu ◽  
Guang Yang ◽  
Xiaoyu Yuan ◽  
Zhongping Chen ◽  
...  

Abstract Background: The liver is the metabolic organ considered to contribute the most to maintaining body iron homeostasis and is a regulator of body adaptation to fasting. Our previous studies implied a negative relationship between iron and ghrelin in both mice and humans and indicated that ghrelin was able to increase ferroportin 1 (Fpn1) expression in the spleen and macrophages through the GHSR/MAPK pathway. However, it remains to be explored whether fasting or ghrelin has a functional effect on iron homeostasis in the liver.Methods: In this study, we examined the roles of fasting and ghrelin in modulating the protein expression of Fpn1, transferrin receptor 1 (TfR1), and ferritin light chain (Ft-L), as well as the mRNA expression of ghrelin, hepcidin, ghrelin O-acyltransferase (GOAT) and growth hormone secretagogue receptor 1 alpha (GHSR1α) in mouse liver and cultured hepatocytes.Results: Our in vivo results suggested that fasting significantly upregulated the mRNA expression of ghrelin, GOAT and GHSR1α as well as the protein levels of ghrelin, Fpn1 and Ft-L, but not TfR1, in mouse liver. Meanwhile, in cultured hepatocytes, ghrelin significantly increased the protein expression of Fpn1 but not Ft-L and TfR1 and significantly enhanced ERK phosphorylation. Furthermore, the pretreatment of cultured hepatocytes with either a pERK inhibitor or a GHSR1α antagonist abolished the effects of ghrelin on Fpn1 expression and ERK phosphorylation.Conclusions: Our findings confirmed that fasting increases iron export in the liver by upregulating Fpn1 expression through the ghrelin/GHSR1α/MAPK signaling pathway.

2020 ◽  
Vol 199 (1) ◽  
pp. 267-277
Author(s):  
Qianqian Luo ◽  
Jianan Hu ◽  
Guang Yang ◽  
Xiaoyu Yuan ◽  
Zhongping Chen ◽  
...  

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 3584-3584
Author(s):  
Arndt Stahler ◽  
Sebastian Stintzing ◽  
Dominik Paul Modest ◽  
Ivan Jelas ◽  
Kathrin Heinrich ◽  
...  

3584 Background: We investigated the role of the MAPK pathway by mRNA expression profiles in microarrays of the FIRE-3 trial as it was formerly associated with prognosis. Methods: 451 patients provided eligible mRNA material for subsequent analyses of the MAPK pathway (295 genes). Non-negative matrix factorized (NMF) clustering for normalized mRNA microarray data (Almac Inc, Xcel Array) was performed for 2 to 6 ranks against randomized controls. Linear models with adjustment for multiple testing showed differential gene expression between groups. Single sample gene set enrichment analysis (ssGSEA) was used to compare differentially enriched hallmarks of cancer gene sets. Kaplan Meier method, log rank test and Cox regression analyses were performed to estimate overall (OS) and progression free survival (PFS) between MAPK subtypes. Results: NMF clustering built two groups of MAPK mRNA expression (coph: 0.91, silh: 1.00) without cohort-based bias in principal component analysis. Group MAPK1 (n = 238) was significantly associated with CMS2 (66.4 %), group MAPK2 (n = 213) with CMS4 (67.6 %, p < 0.0001). 5.551 of 23.561 genes were significantly differentially expressed between MAPK subtypes. 49 cancer hallmark gene sets were significantly differentially enriched in ssGSEA ( MAPK1: myc targets, DNA repair, cell cycle, PI3K- AKT- mTOR pathway upregulation; MAPK2: EMT-related signatures, TGFß pathway, angiogenesis upregulation among others). In overall analysis, MAPK1 showed slightly better outcome than MAPK2 (OS: HR: 0.80, 95% CI: 0.65 – 0.99, p = 0.049; PFS: HR: 0.81, 95% CI: 0.66 – 1.00, p = 0.05). However, MAPK1 was significantly more favourable for bevacizumab treatment in OS ( MAPK1: 30.8 m, MAPK2: 19.4 m, HR: 0.56, 95% CI: 0.39 – 0.81, p = 0.002) and PFS ( MAPK1: 11.7 m, MAPK2: 9.8 m, HR: 0.68, 95% CI: 0.48 – 0.98, p = 0.038) in left sided tumors, while no difference was seen for cetuximab treatment, RAS and BRAF status. Conclusions: mCRC subtypes by MAPK mRNA expression might contain prognostic information for the treatment with bevacizumab beyond mutational status in patients with left sided tumors of the FIRE-3 trial.


Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Xiaoyan Yang ◽  
Athanassios Vassilopoulos ◽  
Seong-Hoon Park ◽  
David Gius ◽  
Hossein Ardehali

Background: Sirtuins (SIRTs) are NAD+-dependent deacetylases and critical regulators of energy metabolism and response to oxidative stress in the heart. Iron is essential for these processes but is toxic when present in excess. Thus, SIRTs may regulate iron levels to ensure adequate supply of this element for their biological functions. SIRT2 is among the least characterized SIRTs and is mainly present in the cytoplasm. We hypothesized that SIRT2 might be required for cellular iron homeostasis. Methods and Results: Iron content was significantly lower in SIRT2-/- mouse embryonic fibroblasts (MEFs) compared to SIRT2+/+ MEFs (non-heme iron: 0.073 vs. 0.060 nmol/μg protein, p=0.02). Gene expression of ferroportin-1 (FPN1), the major cellular iron exporter, was significantly increased in SIRT2-/- MEFs. Similarly, silencing SIRT2 in HepG2 cells decreased cellular iron levels and increased FPN1 expression, indicating that enhanced FPN1 in SIRT2 knockout or knockdown condition increases iron export and reduces cellular iron. To investigate the underlying mechanism, we focused our studies on nuclear factor (erythroid-derived 2)-like 2 (Nrf2), a known regulator of FPN1. Our results demonstrated that Nrf2 is upregulated and translocates into the nucleus in SIRT2-/- MEFs and knocking down Nrf2 in SIRT2-/- MEFs reverses iron deficiency and FPN1 expression. Furthermore, Nrf2 is acetylated by P300/CBP and can be deacetylated by SIRT2. Finally, to confirm the role of SIRT2 in iron regulation, cellular heme and non-heme iron in the heart (major iron-consuming organ) and liver (major iron-storage organ) were measured in wild type (WT) and SIRT2-/- mice. Heme and non-heme iron content were significantly decreased in SIRT2-/- mouse livers compared to WT livers (heme: 2.25 vs. 1.65 nmol/mg protein, p=0.002; non-heme iron: 0.073 vs. 0.064 nmol/μg protein, p=0.03). Furthermore, heme levels were also significant decreased in the heart, while non-heme iron was not significantly altered. Conclusions: Our results suggest that SIRT2 regulates cellular iron homeostasis by deacetylating NRF2 and altering iron export through FPN1.


Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 332
Author(s):  
Taeyeon Hong ◽  
Jiyeon Ham ◽  
Jisoo Song ◽  
Gwonhwa Song ◽  
Whasun Lim

Brassinin is a phytochemical derived from Chinese cabbage, a cruciferous vegetable. Brassinin has shown anticancer effects on prostate and colon cancer cells, among others. However, its mechanisms and effects on hepatocellular carcinoma (HCC) have not been elucidated yet. Our results confirmed that brassinin exerted antiproliferative effects by reducing proliferating cell nuclear antigen (PCNA) activity, a proliferation indicator and inducing cell cycle arrest in human HCC (Huh7 and Hep3B) cells. Brassinin also increased mitochondrial Ca2+ levels and depolarized the mitochondrial membrane in both Huh7 and Hep3B cells. Moreover, brassinin generated high amounts of reactive oxygen species (ROS) in both cell lines. The ROS scavenger N-acetyl-L-cysteine (NAC) inhibited this brassinin-induced ROS production. Brassinin also regulated the AKT and mitogen-activated protein kinases (MAPK) signaling pathways in Huh7 and Hep3B cells. Furthermore, co-administering brassinin and pharmacological inhibitors for JNK, ERK1/2 and P38 decreased cell proliferation in both HCC cell lines more than the pharmacological inhibitors alone. Collectively, our results demonstrated that brassinin exerts antiproliferative effects via mitochondrial dysfunction and MAPK pathway regulation on HCC cells.


Author(s):  
Ghanshyam N Pandey ◽  
Anuradha Sharma ◽  
Hooriyah S Rizavi ◽  
Xinguo Ren

Abstract Background Several lines of evidence suggest the abnormalities of protein kinase C (PKC) signaling system in mood disorders and suicide based primarily on the studies of PKC and its isozymes in the platelets and postmortem brain of depressed and suicidal subjects. In this study we examined the role of PKC isozymes in depression and suicide. Methods We determined the protein and mRNA expression of various PKC isozymes in the prefrontal cortical region [Brodmann area 9 (BA9)] in 24 normal control (NC) subjects, 24 depressed suicide (DS) subjects and 12 depressed non-suicide (DNS) subjects. The levels of mRNA in the prefrontal cortex (PFC) were determined by qRT-PCR and the protein expression was determined by Western blotting. Results We observed a significant decrease in mRNA expression of PKCα, PKCβI, PKCδ and PKCε and decreased protein expression either in the membrane or the cytosol fraction of PKC isozymes - PKCα, PKCβI, PKCβII and PKCδ in DS and DNS subjects compared with NC subjects. Conclusions The current study provides detailed evidence of specific dysregulation of certain PKC isozymes in the postmortem brain of DS and DNS subjects and further supports earlier evidence for the role of PKC in the platelets and brain of adult and teenage depressed and suicidal population. This comprehensive study may lead to further knowledge of the involvement of PKC in the pathophysiology of depression and suicide.


Reproduction ◽  
2015 ◽  
Vol 149 (4) ◽  
pp. 317-327 ◽  
Author(s):  
Martyna Łupicka ◽  
Gabriel Bodek ◽  
Nahum Shpigel ◽  
Ehud Elnekave ◽  
Anna J Korzekwa

The aim of this study was to identify uterine pluripotent cells both in bovine uterine tissues as well in epithelial, stromal, and myometrial uterine cell populations. Moreover, the relationship of pluripotent markers expression with age and the uterine horn side was considered. Uterine tissue was collected from ipsilateral and contralateral horns (days 8–10 of the estrous cycle). Immunohistostaining for C-KIT, OCT3/4, NANOG, and SOX2 in uterine tissue was determined. mRNA expression of C-KIT, OCT3/4, NANOG and SOX2 was evaluated in uterine tissue relative to the age of the cow and uterine horn side. Gene and protein expression of these markers in the uterine luminal epithelial, stromal, and myometrial cells was evaluated by real-time PCR and western blotting respectively. The expression of pluripotent cell markers OCT3/4, NANOG, and SOX2 was identified by flow cytometry assay in epithelial, stromal, and myometrial cells. Multilineage differentiation of the bovine uterine cells was performed. mRNA expression of OCT3/4, NANOG, and SOX2 in uterine tissue was higher in the ipsilateral horn than in the contralateral horn. Flow cytometry assay revealed positive fluorescence for OCT3/4, NANOG, and SOX2 in all uterine cell types. Results showed the age-dependent expression of pluripotent markers in uterine tissue. Beside, the different expression of pluripotent cells in each horn of uterus suggests the influence of ovarian hormones on these characteristics. The highest mRNA and protein expression for pluripotent markers was observed in stromal cells among uterine cells, which indicates this population of cells as the main site of pluripotent cells in the cow uterus.


Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2248 ◽  
Author(s):  
Jian-Ming Chen ◽  
Pei-Yin Chen ◽  
Chia-Chieh Lin ◽  
Ming-Chang Hsieh ◽  
Jen-Tsun Lin

Background: Sesamin is a lignin present in sesame oil from the bark of Zanthoxylum spp. Sesamin reportedly has anticarcinogenic potential and exerts anti-inflammatory effects on several tumors. Hypothesis/Purpose: However, the effect of sesamin on metastatic progression in human head and neck squamous carcinoma (HNSCC) remains unknown in vitro and in vivo; hence, we investigated the effect of sesamin on HNSCC cells in vitro. Methods and Results: Sesamin-treated human oral cancer cell lines FaDu, HSC-3, and Ca9-22 were subjected to a wound-healing assay. Furthermore, Western blotting was performed to assess the effect of sesamin on the expression levels of matrix metalloproteinase (MMP)-2 and proteins of the MAPK signaling pathway, including p-ERK1/2, P-p38, and p-JNK1/2. In addition, we investigated the association between MMP-2 expression and the MAPK pathway in sesamin-treated oral cancer cells. Sesamin inhibited cell migration and invasion in FaDu, Ca9-22, and HSC-3 cells and suppressed MMP-2 at noncytotoxic concentrations (0 to 40 μM). Furthermore, sesamin significantly reduced p38 MAPK and JNK phosphorylation in a dose-dependent manner in FaDu and HSC-3 cells. Conclusions: These results indicate that sesamin suppresses the migration and invasion of HNSCC cells by regulating MMP-2 and is thus a potential antimetastatic agent for treating HNSCC.


2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Xin Hu ◽  
Xiaoqian Shang ◽  
Liang Wang ◽  
Jiahui Fan ◽  
Yue Wang ◽  
...  

Abstract Aim Brucellar spondylitis (BS) is one of the most serious complications of brucellosis. CXCR3 is closely related to the severity of disease infection. This research aimed to study the degree of BS inflammatory damage through analyzing the expression levels of CXCR3 and its ligands (CXCL9 and CXCL10) in patients with BS. Methods A total of 29 BS patients and 15 healthy controls were enrolled. Real-Time PCR was used to detect the mRNA expression levels of IFN-γ, CXCR3, CXCL9 and CXCL10 in peripheral blood mononuclear cells (PBMCs) of BS patients and healthy controls. Hematoxylin-Eosin staining was used to show the pathological changes in BS lesion tissues. Immunohistochemistry staining was used to show the protein expression levels of Brucella-Ab, IFN-γ, CXCR3, CXCL9 and CXCL10 in BS lesion tissues. At the same time, ELISA was used to detect the serum levels of IFN-γ, CXCL9 CXCL10 and autoantibodies against CXCR3 in patients with BS. Results In lesion tissue of BS patients, it showed necrosis of cartilage, acute or chronic inflammatory infiltration. Brucella-Ab protein was abundantly expressed in close lesion tissue. And the protein expression levels of IFN-γ, CXCR3 and CXCL10 were highly expressed in close lesion tissue and serum of BS patients. At the same time, the mRNA expression levels of IFN-γ, CXCR3 and CXCL10 in PBMCs of BS patients were significantly higher than those in controls. Conclusion In our research, the expression levels of IFN-γ, CXCR3 and its ligands were significantly higher than those in controls. It suggested that high expression levels of IFN-γ, CXCR3 and its ligands indicated a serious inflammatory damage in patients with BS.


Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2371
Author(s):  
Selma Benito-Martínez ◽  
Bárbara Pérez-Köhler ◽  
Marta Rodríguez ◽  
Francisca García-Moreno ◽  
Verónica Gómez-Gil ◽  
...  

Prosthetic mesh infection is a devastating complication of abdominal hernia repair which impairs natural healing in the implant area, leading to increased rates of patient morbidity, mortality, and prolonged hospitalization. This preclinical study was designed to assess the effects on abdominal wall tissue repair of coating meshes with a chlorhexidine or rifampicin-carboxymethylcellulose biopolymer gel in a Staphylococcus aureus (S. aureus) infection model. Partial abdominal wall defects were created in New Zealand white rabbits (n = 20). Four study groups were established according to whether the meshes were coated or not with each of the antibacterial gels. Three groups were inoculated with S. aureus and finally repaired with lightweight polypropylene mesh. Fourteen days after surgery, implanted meshes were recovered for analysis of the gene and protein expression of collagens, macrophage phenotypes, and mRNA expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs). Compared to uncoated meshes, those coated with either biopolymer gel showed higher collagen 1/3 messenger RNA and collagen I protein expression, relatively increased VEGF mRNA expression, a significantly reduced macrophage response, and lower relative amounts of MMPs mRNAs. Our findings suggest that following mesh implant these coatings may help improving abdominal wall tissue repair in the presence of infection.


2017 ◽  
Vol 114 (52) ◽  
pp. 13780-13785 ◽  
Author(s):  
Christine M. Scaduto ◽  
Shail Kabrawala ◽  
Gregory J. Thomson ◽  
William Scheving ◽  
Andy Ly ◽  
...  

Several pathogenicCandidaspecies are capable of heritable and reversible switching between two epigenetic states, “white” and “opaque.” InCandida albicans, white cells are essentially sterile, whereas opaque cells are mating-proficient. Here, we interrogate the mechanism by which the white-opaque switch regulates sexual fecundity and identify four genes in the pheromone MAPK pathway that are expressed at significantly higher levels in opaque cells than in white cells. These genes encode the β subunit of the G-protein complex (STE4), the pheromone MAPK scaffold (CST5), and the two terminal MAP kinases (CEK1/CEK2). To define the contribution of each factor to mating,C. albicanswhite cells were reverse-engineered to express elevated, opaque-like levels of these factors, either singly or in combination. We show that white cells co-overexpressingSTE4,CST5, andCEK2undergo mating four orders of magnitude more efficiently than control white cells and at a frequency approaching that of opaque cells. Moreover, engineered white cells recapitulate the transcriptional and morphological responses of opaque cells to pheromone. These results therefore reveal multiple bottlenecks in pheromone MAPK signaling in white cells and that alleviation of these bottlenecks enables efficient mating by these “sterile” cell types. Taken together, our findings establish that differential expression of several MAPK factors underlies the epigenetic control of mating inC. albicans. We also discuss how fitness advantages could have driven the evolution of a toggle switch to regulate sexual reproduction in pathogenicCandidaspecies.


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