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Hydrogen sulfide inhibits A2A adenosine receptor agonist induced β-amyloid production in SH-SY5Y neuroblastoma cells via a cAMP dependent pathway.

Nagpure BV, Bian JS - PLoS ONE (2014)

Bottom Line: NaHS induced reductions were accompanied by similar decreases in intracellular cAMP levels and phosphorylation of cAMP responsive element binding protein (CREB).NaHS significantly reduced the elevated cAMP and Aβ42 production caused by forskolin (an adenylyl cyclase, AC agonist) alone or forskolin in combination with IBMX (a phosphodiesterase inhibitor), but had no effect on those caused by IBMX alone.In conclusion, H2S attenuated HENECA induced Aβ42 production in SH-SY5Y neuroblastoma cells through inhibiting γ-secretase via a cAMP dependent pathway.

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.

ABSTRACT
Alzheimer's disease (AD) is the leading cause of senile dementia in today's society. Its debilitating symptoms are manifested by disturbances in many important brain functions, which are influenced by adenosine. Hence, adenosinergic system is considered as a potential therapeutic target in AD treatment. In the present study, we found that sodium hydrosulfide (NaHS, an H2S donor, 100 µM) attenuated HENECA (a selective A2A receptor agonist, 10-200 nM) induced β-amyloid (1-42) (Aβ42) production in SH-SY5Y cells. NaHS also interfered with HENECA-stimulated production and post-translational modification of amyloid precursor protein (APP) by inhibiting its maturation. Measurement of the C-terminal APP fragments generated from its enzymatic cleavage by β-site amyloid precursor protein cleaving enzyme 1 (BACE1) showed that NaHS did not have any significant effect on β-secretase activity. However, the direct measurements of HENECA-elevated γ-secretase activity and mRNA expressions of presenilins suggested that the suppression of Aβ42 production in NaHS pretreated cells was mediated by inhibiting γ-secretase. NaHS induced reductions were accompanied by similar decreases in intracellular cAMP levels and phosphorylation of cAMP responsive element binding protein (CREB). NaHS significantly reduced the elevated cAMP and Aβ42 production caused by forskolin (an adenylyl cyclase, AC agonist) alone or forskolin in combination with IBMX (a phosphodiesterase inhibitor), but had no effect on those caused by IBMX alone. Moreover, pretreatment with NaHS significantly attenuated HENECA-elevated AC activity and mRNA expressions of various AC isoforms. These data suggest that NaHS may preferentially suppress AC activity when it was stimulated. In conclusion, H2S attenuated HENECA induced Aβ42 production in SH-SY5Y neuroblastoma cells through inhibiting γ-secretase via a cAMP dependent pathway.

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Effect of NaHS on Aβ42 production involved PKA and CREB.A: Effect of HENECA (100 nM) on Aβ42 formation was abolished by a PKA inhibitor, H89 (5, 10 and 15 µM). B–C: Representative gel (B) and histogram (C) depicting that pretreatment with NaHS (100 µM, 12 hours) attenuated the effects of HENECA (100 nM, 24 hours) on phosphorylation of CREB. Control values were adjusted to 100%. Data are given as means ± S.E.M, n = 4–6. ###p<0.001 vs Con group; *p<0.05, **p<0.01, ***p<0.001 vs HEN group. Con, control; HEN, HENECA.
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pone-0088508-g004: Effect of NaHS on Aβ42 production involved PKA and CREB.A: Effect of HENECA (100 nM) on Aβ42 formation was abolished by a PKA inhibitor, H89 (5, 10 and 15 µM). B–C: Representative gel (B) and histogram (C) depicting that pretreatment with NaHS (100 µM, 12 hours) attenuated the effects of HENECA (100 nM, 24 hours) on phosphorylation of CREB. Control values were adjusted to 100%. Data are given as means ± S.E.M, n = 4–6. ###p<0.001 vs Con group; *p<0.05, **p<0.01, ***p<0.001 vs HEN group. Con, control; HEN, HENECA.

Mentions: Blockade of PKA with its selective inhibitor, H-89 (5–15 µM) also dose-dependently attenuated the elevated Aβ42 induced by HENECA (Fig 4A). To examine the involvement of CREB, we determined the phosphorylation of CREB using western blotting. As shown in Fig. 4B and 4C, NaHS treatment significantly attenuated HENECA-induced phosphorylation of CREB. These results suggest that the inhibitory effect of H2S on Aβ42 production involves cAMP/PKA/CREB pathway.


Hydrogen sulfide inhibits A2A adenosine receptor agonist induced β-amyloid production in SH-SY5Y neuroblastoma cells via a cAMP dependent pathway.

Nagpure BV, Bian JS - PLoS ONE (2014)

Effect of NaHS on Aβ42 production involved PKA and CREB.A: Effect of HENECA (100 nM) on Aβ42 formation was abolished by a PKA inhibitor, H89 (5, 10 and 15 µM). B–C: Representative gel (B) and histogram (C) depicting that pretreatment with NaHS (100 µM, 12 hours) attenuated the effects of HENECA (100 nM, 24 hours) on phosphorylation of CREB. Control values were adjusted to 100%. Data are given as means ± S.E.M, n = 4–6. ###p<0.001 vs Con group; *p<0.05, **p<0.01, ***p<0.001 vs HEN group. Con, control; HEN, HENECA.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3921165&req=5

pone-0088508-g004: Effect of NaHS on Aβ42 production involved PKA and CREB.A: Effect of HENECA (100 nM) on Aβ42 formation was abolished by a PKA inhibitor, H89 (5, 10 and 15 µM). B–C: Representative gel (B) and histogram (C) depicting that pretreatment with NaHS (100 µM, 12 hours) attenuated the effects of HENECA (100 nM, 24 hours) on phosphorylation of CREB. Control values were adjusted to 100%. Data are given as means ± S.E.M, n = 4–6. ###p<0.001 vs Con group; *p<0.05, **p<0.01, ***p<0.001 vs HEN group. Con, control; HEN, HENECA.
Mentions: Blockade of PKA with its selective inhibitor, H-89 (5–15 µM) also dose-dependently attenuated the elevated Aβ42 induced by HENECA (Fig 4A). To examine the involvement of CREB, we determined the phosphorylation of CREB using western blotting. As shown in Fig. 4B and 4C, NaHS treatment significantly attenuated HENECA-induced phosphorylation of CREB. These results suggest that the inhibitory effect of H2S on Aβ42 production involves cAMP/PKA/CREB pathway.

Bottom Line: NaHS induced reductions were accompanied by similar decreases in intracellular cAMP levels and phosphorylation of cAMP responsive element binding protein (CREB).NaHS significantly reduced the elevated cAMP and Aβ42 production caused by forskolin (an adenylyl cyclase, AC agonist) alone or forskolin in combination with IBMX (a phosphodiesterase inhibitor), but had no effect on those caused by IBMX alone.In conclusion, H2S attenuated HENECA induced Aβ42 production in SH-SY5Y neuroblastoma cells through inhibiting γ-secretase via a cAMP dependent pathway.

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.

ABSTRACT
Alzheimer's disease (AD) is the leading cause of senile dementia in today's society. Its debilitating symptoms are manifested by disturbances in many important brain functions, which are influenced by adenosine. Hence, adenosinergic system is considered as a potential therapeutic target in AD treatment. In the present study, we found that sodium hydrosulfide (NaHS, an H2S donor, 100 µM) attenuated HENECA (a selective A2A receptor agonist, 10-200 nM) induced β-amyloid (1-42) (Aβ42) production in SH-SY5Y cells. NaHS also interfered with HENECA-stimulated production and post-translational modification of amyloid precursor protein (APP) by inhibiting its maturation. Measurement of the C-terminal APP fragments generated from its enzymatic cleavage by β-site amyloid precursor protein cleaving enzyme 1 (BACE1) showed that NaHS did not have any significant effect on β-secretase activity. However, the direct measurements of HENECA-elevated γ-secretase activity and mRNA expressions of presenilins suggested that the suppression of Aβ42 production in NaHS pretreated cells was mediated by inhibiting γ-secretase. NaHS induced reductions were accompanied by similar decreases in intracellular cAMP levels and phosphorylation of cAMP responsive element binding protein (CREB). NaHS significantly reduced the elevated cAMP and Aβ42 production caused by forskolin (an adenylyl cyclase, AC agonist) alone or forskolin in combination with IBMX (a phosphodiesterase inhibitor), but had no effect on those caused by IBMX alone. Moreover, pretreatment with NaHS significantly attenuated HENECA-elevated AC activity and mRNA expressions of various AC isoforms. These data suggest that NaHS may preferentially suppress AC activity when it was stimulated. In conclusion, H2S attenuated HENECA induced Aβ42 production in SH-SY5Y neuroblastoma cells through inhibiting γ-secretase via a cAMP dependent pathway.

Show MeSH
Related in: MedlinePlus