scholarly journals Evaluation of Commercially Available Glucagon Receptor Antibodies and Glucagon Receptor Expression

2021 ◽  
Author(s):  
Anna Billeschou Bomholt ◽  
Christian Dall Johansen ◽  
Sasha A. S. Kjeldsen ◽  
Katrine Douglas Galsgaard ◽  
Jens Bager Christensen ◽  
...  
Keyword(s):  
Rna Sequencing ◽  
Western Blotting ◽  
Liver Tissue ◽  
Human Liver ◽  
Kidney Tissue ◽  
Receptor Expression ◽  
Hek293 Cells ◽  
Mouse Tissue ◽  
Positive Staining ◽  
Glucagon Receptor

Glucagon is a key regulator of numerous metabolic functions including glucose, protein and lipid metabolism, and glucagon-based therapies are explored for diabetes, fatty liver disease and obesity. Insight into tissue and cell specific expression of the glucagon receptor (GCGR) is important to understand the biology of glucagon as well as to differentiate between direct and indirect actions of glucagon. However, it has been challenging to accurately localize the GCGR in tissue due to low expression levels and lack of specific methodologies. Immunohistochemistry has frequently been used for GCGR localization, but G-protein-coupled receptors (GPCRs) targeting antibodies are notoriously unreliable. In this study, we systematically evaluated all commercially available GCGR antibodies. Initially, twelve GCGR antibodies were evaluated using HEK293 cells transfected with mouse or human GCGR cDNA. Of the twelve antibodies tested, eleven showed positive staining of GCGR protein from both species. Human liver tissue was investigated using the same GCGR antibodies. Five antibodies failed to stain human liver biopsies (despite explicit claims to the contrary from the vendors). Immunohistochemical (IHC) staining demonstrated positive staining of liver tissue from glucagon receptor knockout (Gcgr-/-) mice and their wild-type littermates (Gcgr+/+) with only one out of the twelve available GCGR antibodies. Three antibodies were selected for further evaluation by western blotting and bands corresponding to the predicted size of the GCGR (62 kDa) were identified using two of these. Finally, a single antibody (no. 11) was selected for specific GCGR localization studies in various tissues. In mouse tissue the most intense immunostainings were found in lever, kidney, ileum, heart, and pancreas. Western blotting, performed on liver tissue from Gcgr+/+ and Gcgr-/- mice, confirmed the specificity of antibody no. 11, detecting a band at high intensity in material from Gcgr+/+and no bands in liver tissue from Gcgr-/-mice. Staining of human kidney tissue, with antibody no. 11, showed GCGR localization to the distal tubules. Autoradiography was used as an antibody-independent approach to support the antibody-based findings, revealing specific binding in liver, pancreas, and kidney. As a final approach, RNA-sequencing and single-cell RNA (scRNA)-sequencing were implemented. RNA-sequencing confirmed GCGR presence within liver and kidney tissue. The GCGR was specifically found to be expressed in hepatocytes by scRNA-sequencing and potentially also in collecting and distal tubule cells in the kidney. Our results clearly indicate the liver and the kidneys as the primary targets of glucagon action.

scholarly journals Changes and sex- and age-related differences in the expression of drug metabolizing enzymes in a KRAS-mutant mouse model of lung cancer

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10182
Author(s):  
Xiaoyan Li ◽  
Yiyan Lu ◽  
Xiaojun Ou ◽  
Sijing Zeng ◽  
Ying Wang ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Mouse Model ◽  
Protein Expression ◽  
Western Blotting ◽  
Liver Tissue ◽  
Mutant Mouse ◽  
Kidney Tissue ◽  
Drug Metabolizing Enzymes ◽  
Metabolizing Enzymes ◽  
Age Related

Background This study aimed to systematically profile the alterations and sex- and age-related differences in the drug metabolizing enzymes (DMEs) in a KRAS-mutant mouse model of lung cancer (KRAS mice). Methodology In this study, the LC-MS/MS approach and a probe substrate method were used to detect the alterations in 21 isoforms of DMEs, as well as the enzymatic activities of five isoforms, respectively. Western blotting was applied to study the protein expression of four related receptors. Results The proteins contents of CYP2C29 and CYP3A11, were significantly downregulated in the livers of male KRAS mice at 26 weeks (3.7- and 4.4-fold, respectively, p < 0.05). SULT1A1 and SULT1D1 were upregulated by 1.8- to 7.0- fold at 20 (p = 0.015 and 0.017, respectively) and 26 weeks (p = 0.055 and 0.031, respectively). There were positive correlations between protein expression and enzyme activity for CYP2E1, UGT1A9, SULT1A1 and SULT1D1 (r2 ≥ 0.5, p < 0.001). Western blotting analysis revealed the downregulation of AHR, FXR and PPARα protein expression in male KRAS mice at 26 weeks. For sex-related differences, CYP2E1 was male-predominant and UGT1A2 was female-predominant in the kidney. UGT1A1 and UGT1A5 expression was female-predominant, whereas UGT2B1 exhibited male-predominant expression in liver tissue. For the tissue distribution of DMEs, 21 subtypes of DMEs were all expressed in liver tissue. In the intestine, the expression levels of CYP2C29, CYP27A1, UGT1A2, 1A5, 1A6a, 1A9, 2B1, 2B5 and 2B36 were under the limitation of quantification. The subtypes of CYP7A1, 1B1, 2E1 and UGT1A1, 2A3, 2B34 were detected in kidney tissue. Conclusions This study, for the first time, unveils the variations and sex- and age-related differences in DMEs in C57 BL/6 (WT) mice and KRAS mice.

scholarly journals RIG-I, a novel DAMPs sensor for myoglobin activates NF-κB/caspase-3 signaling in CS-AKI model

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Peng-Tao Wang ◽  
Ning Li ◽  
Xin-Yue Wang ◽  
Jia-Le Chen ◽  
Chen-Hao Geng ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Rna Sequencing ◽  
Western Blotting ◽  
Caspase 3 ◽  
Rat Kidney ◽  
Kidney Tissue ◽  
Kidney Injury ◽  
Cellular Level ◽  
Small Interfering Rnas ◽  
Sprague Dawley

Abstract Background Acute kidney injury (AKI) is the main life-threatening complication of crush syndrome (CS), and myoglobin is accepted as the main pathogenic factor. The pattern recognition receptor retinoicacid-inducible gene I (RIG-I) has been reported to exert anti-viral effects function in the innate immune response. However, it is not clear whether RIG-I plays a role in CS-AKI. The present research was carried out to explore the role of RIG-I in CS-AKI. Methods Sprague-Dawley rats were randomly divided into two groups: the sham and CS groups (n = 12). After administration of anesthesia, the double hind limbs of rats in the CS group were put under a pressure of 3 kg for 16 h to mimic crush conditions. The rats in both groups were denied access to food and water. Rats were sacrificed at 12 h or 36 h after pressure was relieved. The successful establishment of the CS-AKI model was confirmed by serum biochemical analysis and renal histological examination. In addition, RNA sequencing was performed on rat kidney tissue to identify molecular pathways involved in CS-AKI. Furthermore, NRK-52E cells were treated with 200 μmol/L ferrous myoglobin to mimic CS-AKI at the cellular level. The cells and cell supernatant samples were collected at 6 h or 24 h. Small interfering RNAs (siRNA) was used to knock down RIG-I expression. The relative expression levels of molecules involved in the RIG-I pathway in rat kidney or cells samples were measured by quantitative Real-time PCR (qPCR), Western blotting analysis, and immunohistochemistry (IHC) staining. Tumor necrosis factor-α (TNF-α) was detected by ELISA. Co-Immunoprecipitation (Co-IP) assays were used to detect the interaction between RIG-I and myoglobin. Results RNA sequencing of CS-AKI rat kidney tissue revealed that the different expression of RIG-I signaling pathway. qPCR, Western blotting, and IHC assays showed that RIG-I, nuclear factor kappa-B (NF-κB) P65, p-P65, and the apoptotic marker caspase-3 and cleaved caspase-3 were up-regulated in the CS group (P < 0.05). However, the levels of interferon regulatory factor 3 (IRF3), p-IRF3 and the antiviral factor interferon-beta (IFN-β) showed no significant changes between the sham and CS groups. Co-IP assays showed the interaction between RIG-I and myoglobin in the kidneys of the CS group. Depletion of RIG-I could alleviate the myoglobin induced expression of apoptosis-associated molecules via the NF-κB/caspase-3 axis. Conclusion RIG-I is a novel damage-associated molecular patterns (DAMPs) sensor for myoglobin and participates in the NF-κB/caspase-3 signaling pathway in CS-AKI. In the development of CS-AKI, specific intervention in the RIG-I pathway might be a potential therapeutic strategy for CS-AKI.

scholarly journals Effects of a Common Eight Base Pairs Duplication at the Exon 7-Intron 7 Junction on Splicing, Expression, and Function of OCT1

2021 ◽  
Vol 12 ◽  
Author(s):  
Sarah Römer ◽  
Marleen J. Meyer ◽  
Kathrin Klein ◽  
Lennart V. Schneider ◽  
Johannes Matthaei ◽  
...  
Keyword(s):  
Rna Sequencing ◽  
Human Liver ◽  
Organic Cation Transporter ◽  
Hepatic Uptake ◽  
Hek293 Cells ◽  
Base Pairs ◽  
Common Amino Acid ◽  
Huh7 Cells ◽  
Alternatively Spliced ◽  
And Function

Organic cation transporter 1 (OCT1, SLC22A1) is localized in the sinusoidal membrane of human hepatocytes and mediates hepatic uptake of weakly basic or cationic drugs and endogenous compounds. Common amino acid substitutions in OCT1 were associated with altered pharmacokinetics and efficacy of drugs like sumatriptan and fenoterol. Recently, the common splice variant rs35854239 has also been suggested to affect OCT1 function. rs35854239 represents an 8 bp duplication of the donor splice site at the exon 7-intron 7 junction. Here we quantified the extent to which this duplication affects OCT1 splicing and, as a consequence, the expression and the function of OCT1. We used pyrosequencing and deep RNA-sequencing to quantify the effect of rs35854239 on splicing after minigene expression of this variant in HepG2 and Huh7 cells and directly in human liver samples. Further, we analyzed the effects of rs35854239 on OCT1 mRNA expression in total, localization and activity of the resulting OCT1 protein, and on the pharmacokinetics of sumatriptan and fenoterol. The 8 bp duplication caused alternative splicing in 38% (deep RNA-sequencing) to 52% (pyrosequencing) of the minigene transcripts when analyzed in HepG2 and Huh7 cells. The alternatively spliced transcript encodes for a truncated protein that after transient transfection in HEK293 cells was not localized in the plasma membrane and was not able to transport the OCT1 model substrate ASP+. In human liver, however, the alternatively spliced OCT1 transcript was detectable only at very low levels (0.3% in heterozygous and 0.6% in homozygous carriers of the 8 bp duplication, deep RNA-sequencing). The 8 bp duplication was associated with a significant reduction of OCT1 expression in the human liver, but explained only 9% of the general variability in OCT1 expression and was not associated with significant changes in the pharmacokinetics of sumatriptan and fenoterol. Therefore, the rs35854239 variant only partially changes splicing, causing moderate changes in OCT1 expression and may be of only limited therapeutic relevance.

1870-P: Glucagon-Receptor Signaling Reverses Hepatic Steatosis Independent of Leptin Receptor Expression

Diabetes ◽  
2019 ◽  
Vol 68 (Supplement 1) ◽  
pp. 1870-P
Author(s):  
SHELLY NASON ◽  
TEAYOUN KIM ◽  
JESSICA P. ANTIPENKO ◽  
BRIAN FINAN ◽  
RICHARD DIMARCHI ◽  
...  
Keyword(s):  
Hepatic Steatosis ◽  
Leptin Receptor ◽  
Receptor Expression ◽  
Receptor Signaling ◽  
Glucagon Receptor

scholarly journals Implications of cardiac markers in risk-stratification and management for COVID-19 patients

Critical Care ◽  
2021 ◽  
Vol 25 (1) ◽  
Author(s):  
Pengping Li ◽  
Wei Wu ◽  
Tingting Zhang ◽  
Ziyu Wang ◽  
Jie Li ◽  
...  
Keyword(s):  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Risk Stratification ◽  
Rna Sequencing ◽  
High Mortality ◽  
Admission Rate ◽  
Serum Levels ◽  
Receptor Expression ◽  
Cardiac Markers ◽  
Artery Disease

Abstract Background COVID-19 has resulted in high mortality worldwide. Information regarding cardiac markers for precise risk-stratification is limited. We aim to discover sensitive and reliable early-warning biomarkers for optimizing management and improving the prognosis of COVID-19 patients. Methods A total of 2954 consecutive COVID-19 patients who were receiving treatment from the Wuhan Huoshenshan Hospital in China from February 4 to April 10 were included in this retrospective cohort. Serum levels of cardiac markers were collected after admission. Coronary artery disease diagnosis and survival status were recorded. Single-cell RNA-sequencing and bulk RNA-sequencing from different cohorts of non-COVID-19 were performed to analyze SARS-CoV-2 receptor expression. Results Among 2954 COVID-19 patients in the analysis, the median age was 60 years (50–68 years), 1461 (49.5%) were female, and 1515 (51.3%) were severe/critical. Compared to mild/moderate (1439, 48.7%) patients, severe/critical patients showed significantly higher levels of cardiac markers within the first week after admission. In severe/critical COVID-19 patients, those with abnormal serum levels of BNP (42 [24.6%] vs 7 [1.1%]), hs-TNI (38 [48.1%] vs 6 [1.0%]), α- HBDH (55 [10.4%] vs 2 [0.2%]), CK-MB (45 [36.3%] vs 12 [0.9%]), and LDH (56 [12.5%] vs 1 [0.1%]) had a significantly higher mortality rate compared to patients with normal levels. The same trend was observed in the ICU admission rate. Severe/critical COVID-19 patients with pre-existing coronary artery disease (165/1,155 [10.9%]) had more cases of BNP (52 [46.5%] vs 119 [16.5%]), hs-TNI (24 [26.7%] vs 9.6 [%], α- HBDH (86 [55.5%] vs 443 [34.4%]), CK-MB (27 [17.4%] vs 97 [7.5%]), and LDH (65 [41.9%] vs 382 [29.7%]), when compared with those without coronary artery disease. There was enhanced SARS-CoV-2 receptor expression in coronary artery disease compared with healthy controls. From regression analysis, patients with five elevated cardiac markers were at a higher risk of death (hazards ratio 3.4 [95% CI 2.4–4.8]). Conclusions COVID-19 patients with pre-existing coronary artery disease represented a higher abnormal percentage of cardiac markers, accompanied by high mortality and ICU admission rate. BNP together with hs-TNI, α- HBDH, CK-MB and LDH act as a prognostic biomarker in COVID-19 patients with or without pre-existing coronary artery disease.

Human Liver-Specific Nanocarrier in a Novel Mouse Xenograft Model Bearing Noncancerous Human Liver Tissue

2011 ◽  
Vol 46 (2) ◽  
pp. 65-72 ◽  
Author(s):  
Yoshifumi Matsuura ◽  
Hiroshi Yagi ◽  
Sachiko Matsuda ◽  
Osamu Itano ◽  
Koichi Aiura ◽  
...  
Keyword(s):  
Liver Tissue ◽  
Human Liver ◽  
Xenograft Model ◽  
Human Liver Tissue ◽  
Mouse Xenograft ◽  
Mouse Xenograft Model

scholarly journals Long non-coding (lnc)RNA profiling and the role of a key regulator lnc-PNRC2-1 in the transforming growth factor-β1-induced epithelial–mesenchymal transition of CNE1 nasopharyngeal carcinoma cells

2021 ◽  
Vol 49 (3) ◽  
pp. 030006052199651
Author(s):  
Jie Yang ◽  
Enzi Feng ◽  
Yanxin Ren ◽  
Shun Qiu ◽  
Liufang Zhao ◽  
...  
Keyword(s):  
Growth Factor ◽  
Nasopharyngeal Carcinoma ◽  
Rna Sequencing ◽  
Western Blotting ◽  
Transforming Growth Factor ◽  
Epithelial Mesenchymal Transition ◽  
Carcinoma Cells ◽  
Mesenchymal Transition ◽  
Emt Markers ◽  
Tgf Β1

Objectives To identify key long non-coding (lnc)RNAs responsible for the epithelial–mesenchymal transition (EMT) of CNE1 nasopharyngeal carcinoma cells and to investigate possible regulatory mechanisms in EMT. Methods CNE1 cells were divided into transforming growth factor (TGF)-β1-induced EMT and control groups. The mRNA and protein expression of EMT markers was determined by real-time quantitative PCR and western blotting. Differentially expressed genes (DEGs) between the two groups were identified by RNA sequencing analysis, and DEG functions were analyzed by gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses. EMT marker expression was re-evaluated by western blotting after knockdown of a selected lncRNA. Results TGF-β1-induced EMT was characterized by decreased E-cadherin and increased vimentin, N-cadherin, and Twist expression at both mRNA and protein levels. Sixty lncRNA genes were clustered in a heatmap, and mRNA expression of 14 dysregulated lncRNAs was consistent with RNA sequencing. Knockdown of lnc-PNRC2-1 increased expression of its antisense gene MYOM3 and reduced expression of EMT markers, resembling treatment with the TGF-β1 receptor inhibitor LY2109761. Conclusion Various lncRNAs participated indirectly in the TGF-β1-induced EMT of CNE1 cells. Lnc-PNRC2-1 may be a key regulator of this and is a potential target to alleviate CNE1 cell EMT.

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