Differential expression of liver proteins between obesity-prone and obesity-resistant rats in response to a high-fat diet

Rodents respond to a chronic high-fat diet (HFD) in two ways: some readily become obese (obesity prone, OP) and others do not (obesity resistant, OR). Although several hypotheses have been proposed, the mechanisms underlying the inter-individual susceptibility to diet-induced obesity remain to be fully defined. In the present study, two-dimensional gel electrophoresis (2-DE) combined with matrix-assisted laser desorption ionisation time-of-flight MS was carried out for identification of differentially expressed liver proteins in OP and OR rats fed a HFD, in an attempt to discover marker proteins involved in susceptibility and/or resistance to obesity in rat liver. The 2-DE analysis demonstrated that forty spots from 380 visualised spots were differentially regulated between the groups. Among these forty spots, twelve were differentially expressed proteins between OP and OR rats, reaching statistical significance. Of these, five proteins have already been linked to obesity; however, seven proteins involved in obesity susceptibility or resistance were identified for the first time in the present study. In order to validate the proteomic results and gain insight into the metabolic changes between the OP and OR groups, we further confirmed the expression pattern of some proteins of interest by Western blot analysis. Combined results of proteomic analysis with Western blot analysis revealed that reduced lipogenesis and increased fat oxidation were achieved in the livers of OR rats. In conclusion, the present proteomic study is an important advance over the previous steps required for identification of OP and OR rats, and should prove valuable in the search for the pathogenesis of obesity in humans.

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Silencing ferritin alleviates atherosclerosis in mice via regulating the expression levels of matrix metalloproteinases and interleukins

Acta Biochimica Polonica ◽

10.18388/abp.2020_5605 ◽

2021 ◽

Author(s):

Mei Zheng ◽

Lizhuo Li ◽

Yuqian Liu ◽

Yun Liang ◽

Xiaoyong Qi

Keyword(s):

Matrix Metalloproteinases ◽

Western Blot ◽

Knockout Mice ◽

Blot Analysis ◽

High Fat Diet ◽

Western Blot Analysis ◽

High Fat ◽

Expression Levels ◽

Atherosclerotic Lesions ◽

Apoe Knockout Mice

This study was conducted to investigate the roles of ferritin in atherosclerosis. The mouse model of atherosclerosis was established by feeding ApoE knockout mice with a high-fat diet. The mice were then treated with ferritin-overexpressing and -silencing constructs, and assessed for interleukins (ILs) and matrix metalloproteinases (MMPs) levels using ELISA and Western blot analysis. After being fed with a high-fat diet, the ApoE knockout mice developed pro-atherogenic lipid profiles with elevated total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C). They also showed increased atherosclerotic lesions including narrowed lumen diameter, reduced lumen area, and increased plaque size. Following injection of the overexpression and silencing constructs, mRNA levels of ferritin were increased and decreased, respectively, and at the same time the atherosclerotic lesions were aggravated and alleviated, respectively. Further analysis indicated that silencing of ferritin gene reduced IL-1β and IL-10 levels while overexpressing ferritin increased them. On other hand, the TNF-α levels showed an opposite trend. MMP8, MMP12 and MMP13 levels were increased or decreased significantly after the mice were injected with ferritin over-expression or silencing vectors, respectively. Western blot analysis showed that compared to the control, overexpressing ferritin resulted in increased expression of p-JNK while silencing ferritin decreased the expression. Meanwhile, the levels of pc-Jun remained unchanged. Our work demonstrates that ferritin can regulate the progress of atherosclerosis via regulating the expression levels of MMPs and interleukins. Silencing ferritin inhibits the development of atherosclerosis and is, therefore, worth being further investigated as a potential therapeutic approach for this disease.

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Exogenous IGF-1 improves cognitive function in rats with high-fat diet consumption

Journal of Molecular Endocrinology ◽

10.1530/jme-19-0150 ◽

2020 ◽

Vol 64 (2) ◽

pp. 115-123 ◽

Cited By ~ 2

Author(s):

Feng Wang ◽

Lu Wang ◽

Yifeng Wang ◽

Dai Li ◽

Tianpeng Hu ◽

...

Keyword(s):

Oxidative Stress ◽

Cognitive Function ◽

Western Blot ◽

Blot Analysis ◽

High Fat Diet ◽

Western Blot Analysis ◽

High Fat ◽

Anxiety Behavior ◽

And Oxidative Stress ◽

Creb Pathway

Insulin-like growth factor-1 (IGF-1) improves cognitive function, but its mechanism has not been elucidated. The aim of the study was to explore whether IGF-1 exerted its protective effect on cognitive function and anxiety behavior through the activation of PI3K/Akt/CREB pathway in high-fat diet rats. Neuronal cells HT22 were treated with nothing, IGF-1, IGF-1 + LY294002 or IGF-1 + 666-15. Expressions of p-PI3K, p-Akt and p-CREB were measured using Western blot analysis. Thirty C57BL/6J rats were used. After feeding with high-fat diet, normal saline, PEG-IGF-1, PEG-IGF-1 + LY294002 or PEG-IGF-1 + 666-15 was treated. Cognitive function and anxiety behavior were assessed by Morris water maze and open field test. Several inflammation and oxidative stress biomarkers were measured using recognized methods. Expressions of p-PI3K and p-CREB were also measured using Western blot analysis. After IGF-1 treatment in cells, expressions of p-PI3K, p-Akt and p-CREB were increased. Furthermore, LY294002 downregulated the expressions of these three proteins, but 666-15 only inhibited the expression of CREB in the cells. Compared with the control rats, we found abnormalities of cognitive function and anxiety behavior, inhibition of PI3K/Akt/CREB pathway and increase of oxidative stress and inflammation in high-fat diet rats. After PEG-IGF-1 treatment, the changes in high-fat diet rats were reversed. Then, we blocked the pathway and found that these blockers attenuated the protective effects of PEG-IGF-1. In conclusion, IGF-1 improved cognitive function and anxiety behavior in high-fat diet rats and inhibited inflammation and oxidative stress in hippocampus tissue through the activation of PI3K/Akt/CREB pathway.

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A Proteomic Approach to Discovery of Candidate Proteins Involved in the Transformation of Follicular Lymphoma.

Blood ◽

10.1182/blood.v106.11.984.984 ◽

2005 ◽

Vol 106 (11) ◽

pp. 984-984

Author(s):

Guang Fan ◽

Yanping Zhong ◽

Cristina Smith ◽

James Huang ◽

Rita Braziel

Keyword(s):

Western Blot ◽

Blot Analysis ◽

Gel Electrophoresis ◽

Western Blot Analysis ◽

Protein Identification ◽

Differentially Expressed ◽

Signal Transduction Pathways ◽

Differentially Expressed Proteins ◽

2D Gel ◽

2D Gel Analysis

Abstract Background: Follicular lymphoma (FL) undergoes transformation to a high grade diffuse large B-cell lymphoma (tr-DLBCL) in about 50% of patients. During transformation, a more virulent subclone of tumor cells emerges, leading to a rapidly progressive clinical course and resistance to therapy. The identification of proteins involved in transformation is critical for understanding the mechanism of transformation and developing molecularly targeted therapy. In this study, we compared protein expression between grade 1- FL (G1-FL) and tr-DLBCL using 2D-gel electrophoresis and Western blot analysis. Design: Frozen tissue and frozen cells were obtained from the Department of Pathology, Oregon Health and Science University tumor bank. The protein expression profiles of 3 G1-FL and 3 tr-DLBCL were compared using 2D-gel electrophoresis. Protein identification was done using a MALDI mass spectrometer. Frozen cells of an additional 11 non-paired GI-FL and 11 non-paired tr-DLBCL, and 2 pairs of G1-FL and tr-DLBCL specimens were used for Western blot confirmation of the initial 2D-gel findings. Results: 2D-gel analysis and MALDI protein identification revealed 14 differentially expressed proteins between G1-FL and tr-DLBCL (figure 1), all of which are known to play important roles in cellular energy/metabolic pathways, signal transduction pathways, and protein and nuclear synthesis. The two most differentially expressed proteins on 2D-gel analysis were superoxide dismutase (MnSOD2) and growth factor receptor bound protein 2 (Grb2). Western blot analysis of MnSOD2 and Grb2 confirmed their relative over- or under-expression in frozen cells from multiple additional clinical lymphoma samples, including 2 paired- and 22 non-paired G1-FL and tr-DLBCL. Both 2D-gel analysis and Western Blot showed a significantly higher level of expression of MnSOD2 and a lower expression of Grb2 expression in tr-DLBCL (figure 2). Summary: Using proteomic profiling, confirmed by Western blot analysis of clinical G1-FL and tr-DLBCL samples, we have confirmed 2 proteins (MnSOD2 and Grb2) that are expressed at significantly different levels in G1-FL and DLBCL. MnSOD2 is capable of protecting cells from reactive oxygen species and regulating signal transduction pathways to influence cell growth and apoptosis. Inhibition of MnSOD2 has been shown in studies of several cancer cell lines to render cancer cells more susceptible to apoptosis. Grb2 is a member of a critical signaling pathway leading to Ras activation in hematopoietic cells. Both proteins may play a critical role in FL transformation. These proteins have the potential to be therapeutic drug targets, diagnostic and/or prognostic markers, or biomarkers for monitoring therapeutic response. Summary of Differentially Expressed Spots Summary of Differentially Expressed Spots Figure Figure

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Expression of water channel aquaporin-4 during experimental syringomyelia

Journal of Neurosurgery Spine ◽

10.3171/2011.5.spine10303 ◽

2011 ◽

Vol 15 (4) ◽

pp. 428-432 ◽

Cited By ~ 4

Author(s):

Kamran Aghayev ◽

Ercan Bal ◽

Tural Rahimli ◽

Melike Mut ◽

Serdar Balcı ◽

...

Keyword(s):

Western Blot ◽

Blot Analysis ◽

Western Blot Analysis ◽

Water Movement ◽

Dominant Role ◽

Statistical Significance ◽

Water Channel ◽

Bulk Water ◽

Compensatory Mechanism ◽

Experimental Group

Object Aquaporins (aqp) are protein channels providing water transport across cell membranes. The main member of this family expressed in the CNS is aqp-4. The pattern and amount of expression of this channel suggest a dominant role in bulk water movement into the nervous tissue. It has also been shown to play a role in several water balance disorders in the CNS. In this study, the authors investigated the possible role of aqp-4 in syringomyelia. Methods Twenty-five male Wistar-Hannover rats were divided into experimental (20 rats) and control (5 rats) groups. Syringomyelia was induced in the experimental group by kaolin injection into the cisterna magna. Eight weeks later, the animals were killed, and their spinal cords were removed. Central canal dilations were noted in all experimental animals. Immunohistochemistry and Western blot analysis were performed to evaluate aqp-4 expression. Results Both groups demonstrated positive immunoreactive signals to aqp-4. Western blot analysis revealed a slight decrease in the mean aqp-4 value in the experimental group; however, the difference did not reach statistical significance (p > 0.05). Immunohistochemical analysis showed a similar pattern and intensity of aqp-4 staining in both groups. Conclusions The results of this study indicate that aqp-4 most likely does not play a major role in chronic syringomyelia. Its slight downregulation during the initial stage of syrinx formation is possibly a compensatory mechanism. This effect is not present during the late stage of syringomyelia, and aqp-4 is most likely not involved in the pathophysiology of syrinx cavity formation.

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Unsupervised Analysis of Human Leukemia Cells Identifies the Valosin-Containing Protein as a Putative Marker for Glucocorticoid Resistance.

Blood ◽

10.1182/blood.v104.11.167.167 ◽

2004 ◽

Vol 104 (11) ◽

pp. 167-167

Author(s):

Melchior Lauten ◽

Nils v. Neuhoff ◽

Karl Welte ◽

Brigitte Schlegelberger ◽

Martin Schrappe

Keyword(s):

Western Blot ◽

B Cell ◽

Blot Analysis ◽

Western Blot Analysis ◽

Case Control ◽

Differentially Expressed ◽

Glucocorticoid Resistance ◽

Differentially Expressed Proteins ◽

Cell Precursor

Abstract The prednisone response (PR) is a clinical phenomenon in childhood acute lymphoblastic leukemia (ALL) indicating in vivo glucocorticoid (GC) resistance. For patients treated within the ALL-Berlin-Frankfurt-Muenster treatment protocols, the PR is the strongest predictor for therapy outcome. PR is defined by the number of peripheral leukemic blasts on day eight of initial prednisone treatment. The threshold value for the distinction between good and poor prednisone response is 1000 blasts/μl. In trial ALL-BFM 90, prednisone good responders (PGR) had an estimated probability of 6-years event free survival (6y-pEFS) of 82% in contrast to prednisone poor responders (PPR), who showed a 6y-pEFS of only 34% (Schrappe et al., Blood 95(11):3310–3322, 2000). Despite various attempts to elucidate the cause of glucocorticoid resistance, its biological background still remains unclear. Therefore, we performed a case-control study for PR using two-dimensional electrophoresis (2-DE) as screening method to broadly investigate proteome differences in leukemic blasts from in vivo glucocorticoid sensitive and resistant childhood B-cell precursor ALL patients. Producing virtual average gels and difference maps for the proteomes of each responder group by software analysis we identified differentially expressed proteins in glucocorticoid sensitive as well as in glucocorticoid resistant patients. Among the differentially expressed proteins, the valosin-containing protein (VCP) appeared to be overexpressed in PPR. VCP was identified after excision of the respective spot from the 2-DE gel, tryptic digestion and analysis by surface enhanced laser desorption and ionisation (SELDI) mass spectrometry. In previous studies VCP had already been associated with prognosis in different solid tumour entities. This was the reason, why we chose the VCP for validation and quantification by Western Blot analysis. For the Western Blot analysis, a second independent case-control-group of B-cell precursor ALL patients was investigated (cases: 10 PPR, controls: 20 PGR), which confirmed the 2-DE results: median VCP expression (P25-P75) in all ALL samples was 0.19 (0.12 – 0.40) compared to 0.15 (0.11 – 0.28) in PGR and 0.34 (0.14 – 0.99) in PPR patients (P>0.05). This is the first study detecting the association of VCP and GC resistance in two different sets of closely matched patient samples representing one of the leading disease entities treated with GCs.

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Radiosensitivity of glioma to Gamma Knife treatment enhanced in vitro and in vivo by RNA interfering Ku70 that is mediated by a recombinant adenovirus

Journal of Neurosurgery ◽

10.3171/2010.7.gks10972 ◽

2010 ◽

Vol 113 (Special_Supplement) ◽

pp. 228-235 ◽

Cited By ~ 4

Author(s):

Qiang Jia ◽

Yanhe Li ◽

Desheng Xu ◽

Zhenjiang Li ◽

Zhiyuan Zhang ◽

...

Keyword(s):

Western Blot ◽

Gamma Knife ◽

Blot Analysis ◽

Western Blot Analysis ◽

Glioma Cells ◽

C6 Glioma ◽

C6 Glioma Cells ◽

C6 Cells

Object The authors sought to evaluate modification of the radiation response of C6 glioma cells in vitro and in vivo by inhibiting the expression of Ku70. To do so they investigated the effect of gene transfer involving a recombinant replication-defective adenovirus containing Ku70 short hairpin RNA (Ad-Ku70shRNA) combined with Gamma Knife treatment (GKT). Methods First, Ad-Ku70shRNA was transfected into C6 glioma cells and the expression of Ku70 was measured using Western blot analysis. In vitro, phenotypical changes in C6 cells, including proliferation, cell cycle modification, invasion ability, and apoptosis were evaluated using the MTT (3′(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide) assay, Western blot analysis, and cell flow cytometry. In vivo, parental C6 cells transfected with Ad-Ku70shRNA were implanted stereotactically into the right caudate nucleus in Sprague-Dawley rats. After GKS, apoptosis was analyzed using the TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling) method. The inhibitory effects on growth and invasion that were induced by expression of proliferating cell nuclear antigen and matrix metalloproteinase–9 were determined using immunohistochemical analyses. Results The expression of Ku70 was clearly inhibited in C6 cells after transfection with Ad-Ku70shRNA. In vitro following transfection, the C6 cells showed improved responses to GKT, including suppression of proliferation and invasion as well as an increased apoptosis index. In vivo following transfection of Ad-Ku70shRNA, the therapeutic efficacy of GKT in rats with C6 gliomas was greatly enhanced and survival times in these animals were prolonged. Conclusions Our data support the potential for downregulation of Ku70 expression in enhancing the radiosensitivity of gliomas. The findings of our study indicate that targeted gene therapy–mediated inactivation of Ku70 may represent a promising strategy in improving the radioresponsiveness of gliomas to GKT.

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Synthesis and Characterization of Quinoline-3-Carboxamide Derivatives as Inhibitors of the ATM Kinase

Current Topics in Medicinal Chemistry ◽

10.2174/1568026620666200731174216 ◽

2020 ◽

Vol 20 (23) ◽

pp. 2070-2079

Author(s):

Srimadhavi Ravi ◽

Sugata Barui ◽

Sivapriya Kirubakaran ◽

Parul Duhan ◽

Kaushik Bhowmik

Keyword(s):

Western Blot ◽

Cancer Cells ◽

Cell Line ◽

Cell Lines ◽

Cancer Cell ◽

Blot Analysis ◽

Western Blot Analysis ◽

Cancer Cell Lines ◽

Atm Kinase ◽

Cytotoxicity Studies

Background: The importance of inhibiting the kinases of the DDR pathway for radiosensitizing cancer cells is well established. Cancer cells exploit these kinases for their survival, which leads to the development of resistance towards DNA damaging therapeutics. Objective: In this article, the focus is on targeting the key mediator of the DDR pathway, the ATM kinase. A new set of quinoline-3-carboxamides, as potential inhibitors of ATM, is reported. Methods: Quinoline-3-carboxamide derivatives were synthesized and cytotoxicity assay was performed to analyze the effect of molecules on different cancer cell lines like HCT116, MDA-MB-468, and MDA-MB-231. Results: Three of the synthesized compounds showed promising cytotoxicity towards a selected set of cancer cell lines. Western Blot analysis was also performed by pre-treating the cells with quercetin, a known ATM upregulator, by causing DNA double-strand breaks. SAR studies suggested the importance of the electron-donating nature of the R group for the molecule to be toxic. Finally, Western-Blot analysis confirmed the down-regulation of ATM in the cells. Additionally, the PTEN negative cell line, MDA-MB-468, was more sensitive towards the compounds in comparison with the PTEN positive cell line, MDA-MB-231. Cytotoxicity studies against 293T cells showed that the compounds were at least three times less toxic when compared with HCT116. Conclusion: In conclusion, these experiments will lay the groundwork for the evolution of potent and selective ATM inhibitors for the radio- and chemo-sensitization of cancer cells.

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The Antitumor Effects of Britanin on Hepatocellular Carcinoma Cells and its Real-Time Evaluation by In Vivo Bioluminescence Imaging

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666200227092623 ◽

2020 ◽

Vol 20 (9) ◽

pp. 1147-1156

Author(s):

Hanrui Li ◽

GeTao Du ◽

Lu Yang ◽

Liaojun Pang ◽

Yonghua Zhan

Keyword(s):

Hepatocellular Carcinoma ◽

Western Blot ◽

Blot Analysis ◽

Tumor Size ◽

Hepg2 Cells ◽

Western Blot Analysis ◽

Bioluminescence Imaging ◽

Antitumor Effects ◽

In Vivo Bioluminescence Imaging

Background: Hepatocellular carcinoma is cancer with many new cases and the highest mortality rate. Chemotherapy is the most commonly used method for the clinical treatment of hepatocellular carcinoma. Natural products have become clinically important chemotherapeutic drugs due to their great potential for pharmacological development. Many sesquiterpene lactone compounds have been proven to have antitumor effects on hepatocellular carcinoma. Objective: Britanin is a sesquiterpene lactone compound that can be considered for the treatment of hepatocellular carcinoma. The present study aimed to investigate the antitumor effect of britanin. Methods: BEL 7402 and HepG2 cells were used to study the cytotoxicity and antitumor effects of britanin. Preliminary studies on the nuclear factor kappa B pathway were conducted by western blot analysis. A BEL 7402-luc subcutaneous tumor model was established for the in vivo antitumor studies of britanin. In vivo bioluminescence imaging was conducted to monitor changes in tumor size. Results: The results of the cytotoxicity analysis showed that the IC50 values for britanin in BEL 7402 and HepG2 cells were 2.702μM and 6.006μM, respectively. The results of the colony formation demonstrated that the number of cells in a colony was reduced significantly after britanin treatment. And the results of transwell migration assays showed that the migration ability of tumor cells was significantly weakened after treatment with britanin. Tumor size measurements and staining results showed that tumor size was inhibited after britanin treatment. The western blot analysis results showed the inhibition of p65 protein expression and reduced the ratio of Bcl-2/Bax after treatment. Conclusion: A series of in vitro and in vivo experiments demonstrated that britanin had good antitumor effects and provided an option for hepatocellular carcinoma treatment.

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Punicalagin Prevents Inflammation in LPS-Induced RAW264.7 Macrophages by Inhibiting FoxO3a/Autophagy Signaling Pathway

Nutrients ◽

10.3390/nu11112794 ◽

2019 ◽

Vol 11 (11) ◽

pp. 2794 ◽

Cited By ~ 8

Author(s):

Cao ◽

Chen ◽

Ren ◽

Zhang ◽

Tan ◽

...

Keyword(s):

Western Blot ◽

Signaling Pathway ◽

Inflammatory Cytokines ◽

Blot Analysis ◽

Western Blot Analysis ◽

Inflammatory Responses ◽

Raw264.7 Macrophages ◽

Tnf Α ◽

Autophagy Inhibition ◽

Pro Inflammatory Cytokines

Punicalagin, a hydrolysable tannin of pomegranate juice, exhibits multiple biological effects, including inhibiting production of pro-inflammatory cytokines in macrophages. Autophagy, an intracellular self-digestion process, has been recently shown to regulate inflammatory responses. In this study, we investigated the anti-inflammatory potential of punicalagin in lipopolysaccharide (LPS) induced RAW264.7 macrophages and uncovered the underlying mechanisms. Punicalagin significantly attenuated, in a concentration-dependent manner, LPS-induced release of NO and decreased pro-inflammatory cytokines TNF-α and IL-6 release at the highest concentration. We found that punicalagin inhibited NF-κB and MAPK activation in LPS-induced RAW264.7 macrophages. Western blot analysis revealed that punicalagin pre-treatment enhanced LC3II, p62 expression, and decreased Beclin1 expression in LPS-induced macrophages. MDC assays were used to determine the autophagic process and the results worked in concert with Western blot analysis. In addition, our observations indicated that LPS-induced releases of NO, TNF-α, and IL-6 were attenuated by treatment with autophagy inhibitor chloroquine, suggesting that autophagy inhibition participated in anti-inflammatory effect. We also found that punicalagin downregulated FoxO3a expression, resulting in autophagy inhibition. Overall these results suggested that punicalagin played an important role in the attenuation of LPS-induced inflammatory responses in RAW264.7 macrophages and that the mechanisms involved downregulation of the FoxO3a/autophagy signaling pathway.

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Protocol for determining protein cysteine thiol redox status using western blot analysis

STAR Protocols ◽

10.1016/j.xpro.2021.100566 ◽

2021 ◽

Vol 2 (2) ◽

pp. 100566

Author(s):

Bikram Datt Pant ◽

Sunhee Oh ◽

Kirankumar S. Mysore

Keyword(s):

Western Blot ◽

Blot Analysis ◽

Western Blot Analysis ◽

Redox Status ◽

Thiol Redox

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