Limits...
The Orphan Nuclear Receptor NR4A1 Protects Pancreatic β-Cells from Endoplasmic Reticulum (ER) Stress-mediated Apoptosis.

Yu C, Cui S, Zong C, Gao W, Xu T, Gao P, Chen J, Qin D, Guan Q, Liu Y, Fu Y, Li X, Wang X - J. Biol. Chem. (2015)

Bottom Line: This conclusion was further confirmed by experiments exploiting siRNA to knockdown NR4A1 expression in MIN6 cells or exploiting NR4A1 knock-out mice.NR4A1 overexpression in MIN6 cells or mouse islets resulted in Survivin up-regulation.In conclusion, NR4A1 protects pancreatic β-cells against ER stress-mediated apoptosis by up-regulating Survivin expression and down-regulating CHOP expression, which we termed as "positive and negative regulation."

View Article: PubMed Central - PubMed

Affiliation: From the The Department of Cell Biology, Shandong University School of Medicine, Jinan, China, 250012.

Show MeSH

Related in: MedlinePlus

Mouse islets expressing different NR4A1 levels determines their ability to resist TG- or PA-induced apoptosis.A, genotype confirmation of global NR4A1 knock-out mice (KO) and wild-type mice (WT) using RT-PCR to analyze their islets. B and C, TUNEL assay of islet cells from KO and WT mice treated with 0.5 μm TG (B) or o.4 mm PA (C) for 20 h. Blue represents DAPI, and red represents the apoptotic cells. D and E, TUNEL assay of islet cells from wild-type mice infected with Ad-GFP or Ad-NR4A1 after treated with 0.5 μm TG (D) or o.4 mm PA (E) for 20 h. Green represents GFP, and red represents the apoptotic cells. The histograms were made to assess relative fluorescence intensity (=total red densitometry value/islet surface area). The data show the means of three independent experiments; *, p < 0.05; **, p < 0.01; ***, p < 0.001 versus WT or Ad-GFP. F, a model for possible roles of NR4A1 in protecting ER stress induced pancreatic β-cell apoptosis.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4543630&req=5

Figure 8: Mouse islets expressing different NR4A1 levels determines their ability to resist TG- or PA-induced apoptosis.A, genotype confirmation of global NR4A1 knock-out mice (KO) and wild-type mice (WT) using RT-PCR to analyze their islets. B and C, TUNEL assay of islet cells from KO and WT mice treated with 0.5 μm TG (B) or o.4 mm PA (C) for 20 h. Blue represents DAPI, and red represents the apoptotic cells. D and E, TUNEL assay of islet cells from wild-type mice infected with Ad-GFP or Ad-NR4A1 after treated with 0.5 μm TG (D) or o.4 mm PA (E) for 20 h. Green represents GFP, and red represents the apoptotic cells. The histograms were made to assess relative fluorescence intensity (=total red densitometry value/islet surface area). The data show the means of three independent experiments; *, p < 0.05; **, p < 0.01; ***, p < 0.001 versus WT or Ad-GFP. F, a model for possible roles of NR4A1 in protecting ER stress induced pancreatic β-cell apoptosis.

Mentions: To investigate whether a lack of NR4A1 effects β-cell death under ER stress conditions in mouse islets, we purified islets from global NR4A1 knock-out mice (KO) and wild-type mice (WT). First, we did genotype identification by RT-PCR to amplify the full-length cDNA using a specific pair of primer and found there is no mRNA expression of NR4A1 in KO mice islets compared with WT mice (Fig. 8A). We treated the purified islets with TG or PA for 20 h, and TUNEL assays showed that the rate of apoptotic cells is much higher in KO islets than that in WT (Fig. 8, B and C). Moreover, we also overexpressed NR4A1 in islets from wild-type mice by viral infection with Ad-NR4A1. After infection for 48 h, the islets were treated with TG or PA for 20 h, and TUNEL assays showed that the rate of apoptotic cells is much lower in NR4A1 overexpressed islets than that of control islets infected with control virus (Ad- GFP) (Fig. 8, D and E).


The Orphan Nuclear Receptor NR4A1 Protects Pancreatic β-Cells from Endoplasmic Reticulum (ER) Stress-mediated Apoptosis.

Yu C, Cui S, Zong C, Gao W, Xu T, Gao P, Chen J, Qin D, Guan Q, Liu Y, Fu Y, Li X, Wang X - J. Biol. Chem. (2015)

Mouse islets expressing different NR4A1 levels determines their ability to resist TG- or PA-induced apoptosis.A, genotype confirmation of global NR4A1 knock-out mice (KO) and wild-type mice (WT) using RT-PCR to analyze their islets. B and C, TUNEL assay of islet cells from KO and WT mice treated with 0.5 μm TG (B) or o.4 mm PA (C) for 20 h. Blue represents DAPI, and red represents the apoptotic cells. D and E, TUNEL assay of islet cells from wild-type mice infected with Ad-GFP or Ad-NR4A1 after treated with 0.5 μm TG (D) or o.4 mm PA (E) for 20 h. Green represents GFP, and red represents the apoptotic cells. The histograms were made to assess relative fluorescence intensity (=total red densitometry value/islet surface area). The data show the means of three independent experiments; *, p < 0.05; **, p < 0.01; ***, p < 0.001 versus WT or Ad-GFP. F, a model for possible roles of NR4A1 in protecting ER stress induced pancreatic β-cell apoptosis.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4543630&req=5

Figure 8: Mouse islets expressing different NR4A1 levels determines their ability to resist TG- or PA-induced apoptosis.A, genotype confirmation of global NR4A1 knock-out mice (KO) and wild-type mice (WT) using RT-PCR to analyze their islets. B and C, TUNEL assay of islet cells from KO and WT mice treated with 0.5 μm TG (B) or o.4 mm PA (C) for 20 h. Blue represents DAPI, and red represents the apoptotic cells. D and E, TUNEL assay of islet cells from wild-type mice infected with Ad-GFP or Ad-NR4A1 after treated with 0.5 μm TG (D) or o.4 mm PA (E) for 20 h. Green represents GFP, and red represents the apoptotic cells. The histograms were made to assess relative fluorescence intensity (=total red densitometry value/islet surface area). The data show the means of three independent experiments; *, p < 0.05; **, p < 0.01; ***, p < 0.001 versus WT or Ad-GFP. F, a model for possible roles of NR4A1 in protecting ER stress induced pancreatic β-cell apoptosis.
Mentions: To investigate whether a lack of NR4A1 effects β-cell death under ER stress conditions in mouse islets, we purified islets from global NR4A1 knock-out mice (KO) and wild-type mice (WT). First, we did genotype identification by RT-PCR to amplify the full-length cDNA using a specific pair of primer and found there is no mRNA expression of NR4A1 in KO mice islets compared with WT mice (Fig. 8A). We treated the purified islets with TG or PA for 20 h, and TUNEL assays showed that the rate of apoptotic cells is much higher in KO islets than that in WT (Fig. 8, B and C). Moreover, we also overexpressed NR4A1 in islets from wild-type mice by viral infection with Ad-NR4A1. After infection for 48 h, the islets were treated with TG or PA for 20 h, and TUNEL assays showed that the rate of apoptotic cells is much lower in NR4A1 overexpressed islets than that of control islets infected with control virus (Ad- GFP) (Fig. 8, D and E).

Bottom Line: This conclusion was further confirmed by experiments exploiting siRNA to knockdown NR4A1 expression in MIN6 cells or exploiting NR4A1 knock-out mice.NR4A1 overexpression in MIN6 cells or mouse islets resulted in Survivin up-regulation.In conclusion, NR4A1 protects pancreatic β-cells against ER stress-mediated apoptosis by up-regulating Survivin expression and down-regulating CHOP expression, which we termed as "positive and negative regulation."

View Article: PubMed Central - PubMed

Affiliation: From the The Department of Cell Biology, Shandong University School of Medicine, Jinan, China, 250012.

Show MeSH
Related in: MedlinePlus