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SIRT1 reduction causes renal and retinal injury in diabetes through endothelin 1 and transforming growth factor β1.

Mortuza R, Feng B, Chakrabarti S - J. Cell. Mol. Med. (2015)

Bottom Line: Previously we showed glucose reduces sirtuin1 (SIRT1), a class III histone deacetylase.These cells also showed increased p300 expression, histone acetylation and reduced SIRT1 levels.These changes were rectified in the ECs following p300 silencing or by SIRT1 overexpression, whereas SIRT1 knockdown or p300 overexpression in NG mimicked the effects of HG.

View Article: PubMed Central - PubMed

Affiliation: Department of Pathology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada.

No MeSH data available.


Related in: MedlinePlus

SIRT1 regulates ET-1 and TGF-β1 via p300. HG caused increased (A) p300 mRNA and reduced (B) SIRT1 mRNA levels in ECs. (A) Ad-SIRT1 transfection in HG prevented p300 up-regulation and SIRT1 knockdown with siRNA in NG up-regulated p300 mRNA levels. (B) p300 siRNA transfection in HG (efficiency in A) normalized SIRT1 expression. Furthermore, p300 overexpression in NG (efficiency in A) reduced SIRT1 mRNA levels. (C and D) HG induced ET-1 and TGF-β1 up-regulation was abrogated with p300 siRNA (not with scramble) transfection. p300 overexpression in NG up-regulated the expressions of these transcripts. (E and F) Rescue experiment showing up-regulation of ET-1 and TGF-β1 mRNA levels in NG with SIRT1 knockdown can be resolved with subsequent p300 knockdown in the ECs. NG = 5 mmol/l glucose, HG = 25 mmol/l glucose, OSM = osmotic control, * = significantly different from NG, ╪ = significantly different from HG, mRNA levels are expressed as a ratio of 18s. All data (mean ± SEM, P < 0.05) were normalized to NG; n = 4–6/group.
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fig02: SIRT1 regulates ET-1 and TGF-β1 via p300. HG caused increased (A) p300 mRNA and reduced (B) SIRT1 mRNA levels in ECs. (A) Ad-SIRT1 transfection in HG prevented p300 up-regulation and SIRT1 knockdown with siRNA in NG up-regulated p300 mRNA levels. (B) p300 siRNA transfection in HG (efficiency in A) normalized SIRT1 expression. Furthermore, p300 overexpression in NG (efficiency in A) reduced SIRT1 mRNA levels. (C and D) HG induced ET-1 and TGF-β1 up-regulation was abrogated with p300 siRNA (not with scramble) transfection. p300 overexpression in NG up-regulated the expressions of these transcripts. (E and F) Rescue experiment showing up-regulation of ET-1 and TGF-β1 mRNA levels in NG with SIRT1 knockdown can be resolved with subsequent p300 knockdown in the ECs. NG = 5 mmol/l glucose, HG = 25 mmol/l glucose, OSM = osmotic control, * = significantly different from NG, ╪ = significantly different from HG, mRNA levels are expressed as a ratio of 18s. All data (mean ± SEM, P < 0.05) were normalized to NG; n = 4–6/group.

Mentions: In order to investigate the mechanism of such SIRT1 mediated ET-1 and TGF-β1 regulation we looked at transcriptional co-activator p300, as we previously have found SIRT1 and p300 balance each other 20. In keeping with the earlier findings we noted SIRT1 overexpression with adenovirus in 25 mmol/l glucose normalizes glucose-induced augmented p300 mRNA levels (Fig.2A). On the contrary, SIRT1 knockdown in NG with siRNA caused an increase in p300 mRNA levels (Fig.2A). Furthermore, p300 overexpression in these cells in NG reduced the SIRT1 mRNA levels (Fig.2B and C). These changes were not seen with vector, scramble siRNA and p300 mutant transfections. These results re-established a regulatory and balancing role of SIRT1 and p300 on each other in ECs.


SIRT1 reduction causes renal and retinal injury in diabetes through endothelin 1 and transforming growth factor β1.

Mortuza R, Feng B, Chakrabarti S - J. Cell. Mol. Med. (2015)

SIRT1 regulates ET-1 and TGF-β1 via p300. HG caused increased (A) p300 mRNA and reduced (B) SIRT1 mRNA levels in ECs. (A) Ad-SIRT1 transfection in HG prevented p300 up-regulation and SIRT1 knockdown with siRNA in NG up-regulated p300 mRNA levels. (B) p300 siRNA transfection in HG (efficiency in A) normalized SIRT1 expression. Furthermore, p300 overexpression in NG (efficiency in A) reduced SIRT1 mRNA levels. (C and D) HG induced ET-1 and TGF-β1 up-regulation was abrogated with p300 siRNA (not with scramble) transfection. p300 overexpression in NG up-regulated the expressions of these transcripts. (E and F) Rescue experiment showing up-regulation of ET-1 and TGF-β1 mRNA levels in NG with SIRT1 knockdown can be resolved with subsequent p300 knockdown in the ECs. NG = 5 mmol/l glucose, HG = 25 mmol/l glucose, OSM = osmotic control, * = significantly different from NG, ╪ = significantly different from HG, mRNA levels are expressed as a ratio of 18s. All data (mean ± SEM, P < 0.05) were normalized to NG; n = 4–6/group.
© Copyright Policy - open-access
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4549036&req=5

fig02: SIRT1 regulates ET-1 and TGF-β1 via p300. HG caused increased (A) p300 mRNA and reduced (B) SIRT1 mRNA levels in ECs. (A) Ad-SIRT1 transfection in HG prevented p300 up-regulation and SIRT1 knockdown with siRNA in NG up-regulated p300 mRNA levels. (B) p300 siRNA transfection in HG (efficiency in A) normalized SIRT1 expression. Furthermore, p300 overexpression in NG (efficiency in A) reduced SIRT1 mRNA levels. (C and D) HG induced ET-1 and TGF-β1 up-regulation was abrogated with p300 siRNA (not with scramble) transfection. p300 overexpression in NG up-regulated the expressions of these transcripts. (E and F) Rescue experiment showing up-regulation of ET-1 and TGF-β1 mRNA levels in NG with SIRT1 knockdown can be resolved with subsequent p300 knockdown in the ECs. NG = 5 mmol/l glucose, HG = 25 mmol/l glucose, OSM = osmotic control, * = significantly different from NG, ╪ = significantly different from HG, mRNA levels are expressed as a ratio of 18s. All data (mean ± SEM, P < 0.05) were normalized to NG; n = 4–6/group.
Mentions: In order to investigate the mechanism of such SIRT1 mediated ET-1 and TGF-β1 regulation we looked at transcriptional co-activator p300, as we previously have found SIRT1 and p300 balance each other 20. In keeping with the earlier findings we noted SIRT1 overexpression with adenovirus in 25 mmol/l glucose normalizes glucose-induced augmented p300 mRNA levels (Fig.2A). On the contrary, SIRT1 knockdown in NG with siRNA caused an increase in p300 mRNA levels (Fig.2A). Furthermore, p300 overexpression in these cells in NG reduced the SIRT1 mRNA levels (Fig.2B and C). These changes were not seen with vector, scramble siRNA and p300 mutant transfections. These results re-established a regulatory and balancing role of SIRT1 and p300 on each other in ECs.

Bottom Line: Previously we showed glucose reduces sirtuin1 (SIRT1), a class III histone deacetylase.These cells also showed increased p300 expression, histone acetylation and reduced SIRT1 levels.These changes were rectified in the ECs following p300 silencing or by SIRT1 overexpression, whereas SIRT1 knockdown or p300 overexpression in NG mimicked the effects of HG.

View Article: PubMed Central - PubMed

Affiliation: Department of Pathology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada.

No MeSH data available.


Related in: MedlinePlus