Limits...
BDNF-TrkB pathway mediates neuroprotection of hydrogen sulfide against formaldehyde-induced toxicity to PC12 cells.

Jiang JM, Zhou CF, Gao SL, Tian Y, Wang CY, Wang L, Gu HF, Tang XQ - PLoS ONE (2015)

Bottom Line: In the present study, we found that NaHS, a donor of H2S, upregulated the level of BDNF protein in PC12 cells, and significantly rescued FA-induced downregulation of BDNF levels.Furthermore, we found that pretreatment of PC12 cells with K252a, an inhibitor of the BDNF receptor TrkB, markedly reversed the inhibition of NaHS on FA-induced cytotoxicity and ablated the protective effects of NaHS on FA-induced oxidative stress, including the accumulation of intracellular reactive oxygen species (ROS), 4-hydroxy-2-trans-nonenal (4-HNE), and malondialdehyde (MDA).We also showed that K252a abolished the inhibition of NaHS on FA-induced apoptosis, as well as the activation of caspase-3 in PC12 cells.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology & Institute of Neuroscience, Medical College, University of South China, Hengyang, 42100, Hunan, P. R. China; Key Laboratory for Cognitive Disorders and Neurodegenerative Diseases, University of South China, Hengyang, 421001, Hunan, P. R. China.

ABSTRACT
Formaldehyde (FA) is a common environmental contaminant that has toxic effects on the central nervous system (CNS). Our previous data demonstrated that hydrogen sulfide (H2S), the third endogenous gaseous mediator, has protective effects against FA-induced neurotoxicity. As is known to all, Brain-derived neurotropic factor (BDNF), a member of the neurotrophin gene family, mediates its neuroprotective properties via various intracellular signaling pathways triggered by activating the tyrosine kinase receptor B (TrkB). Intriguingly, our previous data have illustrated the upregulatory role of H2S on BDNF protein expression in the hippocampus of rats. Therefore, in this study, we hypothesized that H2S provides neuroprotection against FA toxicity by regulating BDNF-TrkB pathway. In the present study, we found that NaHS, a donor of H2S, upregulated the level of BDNF protein in PC12 cells, and significantly rescued FA-induced downregulation of BDNF levels. Furthermore, we found that pretreatment of PC12 cells with K252a, an inhibitor of the BDNF receptor TrkB, markedly reversed the inhibition of NaHS on FA-induced cytotoxicity and ablated the protective effects of NaHS on FA-induced oxidative stress, including the accumulation of intracellular reactive oxygen species (ROS), 4-hydroxy-2-trans-nonenal (4-HNE), and malondialdehyde (MDA). We also showed that K252a abolished the inhibition of NaHS on FA-induced apoptosis, as well as the activation of caspase-3 in PC12 cells. In addition, K252a reversed the protection of H2S against FA-induced downregulation of Bcl-2 protein expression and upregulation of Bax protein expression in PC12 cells. These data indicate that the BDNF-TrkB pathway mediates the neuroprotection of H2S against FA-induced cytotoxicity, oxidative stress and apoptosis in PC12 cells. These findings provide a novel mechanism underlying the protection of H2S against FA-induced neurotoxicity.

Show MeSH

Related in: MedlinePlus

Effect of K252a on H2S-induced protection against formaldehyde-elicited apoptosis in PC12 cells.PC12 cells were preincubated with K252a (10 nM) for 30 min before pretreatment with NaHS (200 μM) for 30 min, and then cotreated with formaldehyde (FA, 120 μM) for 24 h. (A) The rate of apoptosis was assessed by flow cytometry after PI staining. (B) The activity of caspase-3 was determined by caspase-3 activity Elisa kit. Results were expressed as the mean ± S.E.M. of three independent experiments. *P < 0.05, **P < 0.01, versus control group; ##P < 0.01, versus FA-treated alone group; &&P < 0.01, versus cotreated with NaHS and FA group.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4352058&req=5

pone.0119478.g005: Effect of K252a on H2S-induced protection against formaldehyde-elicited apoptosis in PC12 cells.PC12 cells were preincubated with K252a (10 nM) for 30 min before pretreatment with NaHS (200 μM) for 30 min, and then cotreated with formaldehyde (FA, 120 μM) for 24 h. (A) The rate of apoptosis was assessed by flow cytometry after PI staining. (B) The activity of caspase-3 was determined by caspase-3 activity Elisa kit. Results were expressed as the mean ± S.E.M. of three independent experiments. *P < 0.05, **P < 0.01, versus control group; ##P < 0.01, versus FA-treated alone group; &&P < 0.01, versus cotreated with NaHS and FA group.

Mentions: We further investigated whether K252a reverses the protection of NaHS against FA-induced apoptosis. The statistical findings from FCM analysis after PI staining indicated that K252a reverses the protection of NaHS against FA-induced apoptosis. As shown in Fig. 5A, exposure of PC12 cells to FA (120 μM, for 24 h) caused significant apoptosis and the apoptotic effects induced by FA were inhibited by co-treatment with NaHS (200 μM) for 24 h; however, this protective effect of NaHS was markedly prevented by pretreatment with 10 nM of k252a for 30 min. Caspase-3 is a critical executioner of apoptosis. As shown in Fig. 5B, pretreatment with k252a (10 nM, for 30 min) significantly abolished NaHS (200 μM, for 24 h)-suppressed the increase in caspase-3 activity induced by treatment of 120 μM of FA for 24 h. In addition, the activity of caspase-3 was also decreased caused by NaHS alone (Fig. 5B), which was consistent with the protection of NaHS against FA-induced apoptosis. These data indicated that BDNF-TrkB pathway mediates H2S-caused protection against FA-induced apoptosis in PC12 cells.


BDNF-TrkB pathway mediates neuroprotection of hydrogen sulfide against formaldehyde-induced toxicity to PC12 cells.

Jiang JM, Zhou CF, Gao SL, Tian Y, Wang CY, Wang L, Gu HF, Tang XQ - PLoS ONE (2015)

Effect of K252a on H2S-induced protection against formaldehyde-elicited apoptosis in PC12 cells.PC12 cells were preincubated with K252a (10 nM) for 30 min before pretreatment with NaHS (200 μM) for 30 min, and then cotreated with formaldehyde (FA, 120 μM) for 24 h. (A) The rate of apoptosis was assessed by flow cytometry after PI staining. (B) The activity of caspase-3 was determined by caspase-3 activity Elisa kit. Results were expressed as the mean ± S.E.M. of three independent experiments. *P < 0.05, **P < 0.01, versus control group; ##P < 0.01, versus FA-treated alone group; &&P < 0.01, versus cotreated with NaHS and FA group.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4352058&req=5

pone.0119478.g005: Effect of K252a on H2S-induced protection against formaldehyde-elicited apoptosis in PC12 cells.PC12 cells were preincubated with K252a (10 nM) for 30 min before pretreatment with NaHS (200 μM) for 30 min, and then cotreated with formaldehyde (FA, 120 μM) for 24 h. (A) The rate of apoptosis was assessed by flow cytometry after PI staining. (B) The activity of caspase-3 was determined by caspase-3 activity Elisa kit. Results were expressed as the mean ± S.E.M. of three independent experiments. *P < 0.05, **P < 0.01, versus control group; ##P < 0.01, versus FA-treated alone group; &&P < 0.01, versus cotreated with NaHS and FA group.
Mentions: We further investigated whether K252a reverses the protection of NaHS against FA-induced apoptosis. The statistical findings from FCM analysis after PI staining indicated that K252a reverses the protection of NaHS against FA-induced apoptosis. As shown in Fig. 5A, exposure of PC12 cells to FA (120 μM, for 24 h) caused significant apoptosis and the apoptotic effects induced by FA were inhibited by co-treatment with NaHS (200 μM) for 24 h; however, this protective effect of NaHS was markedly prevented by pretreatment with 10 nM of k252a for 30 min. Caspase-3 is a critical executioner of apoptosis. As shown in Fig. 5B, pretreatment with k252a (10 nM, for 30 min) significantly abolished NaHS (200 μM, for 24 h)-suppressed the increase in caspase-3 activity induced by treatment of 120 μM of FA for 24 h. In addition, the activity of caspase-3 was also decreased caused by NaHS alone (Fig. 5B), which was consistent with the protection of NaHS against FA-induced apoptosis. These data indicated that BDNF-TrkB pathway mediates H2S-caused protection against FA-induced apoptosis in PC12 cells.

Bottom Line: In the present study, we found that NaHS, a donor of H2S, upregulated the level of BDNF protein in PC12 cells, and significantly rescued FA-induced downregulation of BDNF levels.Furthermore, we found that pretreatment of PC12 cells with K252a, an inhibitor of the BDNF receptor TrkB, markedly reversed the inhibition of NaHS on FA-induced cytotoxicity and ablated the protective effects of NaHS on FA-induced oxidative stress, including the accumulation of intracellular reactive oxygen species (ROS), 4-hydroxy-2-trans-nonenal (4-HNE), and malondialdehyde (MDA).We also showed that K252a abolished the inhibition of NaHS on FA-induced apoptosis, as well as the activation of caspase-3 in PC12 cells.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology & Institute of Neuroscience, Medical College, University of South China, Hengyang, 42100, Hunan, P. R. China; Key Laboratory for Cognitive Disorders and Neurodegenerative Diseases, University of South China, Hengyang, 421001, Hunan, P. R. China.

ABSTRACT
Formaldehyde (FA) is a common environmental contaminant that has toxic effects on the central nervous system (CNS). Our previous data demonstrated that hydrogen sulfide (H2S), the third endogenous gaseous mediator, has protective effects against FA-induced neurotoxicity. As is known to all, Brain-derived neurotropic factor (BDNF), a member of the neurotrophin gene family, mediates its neuroprotective properties via various intracellular signaling pathways triggered by activating the tyrosine kinase receptor B (TrkB). Intriguingly, our previous data have illustrated the upregulatory role of H2S on BDNF protein expression in the hippocampus of rats. Therefore, in this study, we hypothesized that H2S provides neuroprotection against FA toxicity by regulating BDNF-TrkB pathway. In the present study, we found that NaHS, a donor of H2S, upregulated the level of BDNF protein in PC12 cells, and significantly rescued FA-induced downregulation of BDNF levels. Furthermore, we found that pretreatment of PC12 cells with K252a, an inhibitor of the BDNF receptor TrkB, markedly reversed the inhibition of NaHS on FA-induced cytotoxicity and ablated the protective effects of NaHS on FA-induced oxidative stress, including the accumulation of intracellular reactive oxygen species (ROS), 4-hydroxy-2-trans-nonenal (4-HNE), and malondialdehyde (MDA). We also showed that K252a abolished the inhibition of NaHS on FA-induced apoptosis, as well as the activation of caspase-3 in PC12 cells. In addition, K252a reversed the protection of H2S against FA-induced downregulation of Bcl-2 protein expression and upregulation of Bax protein expression in PC12 cells. These data indicate that the BDNF-TrkB pathway mediates the neuroprotection of H2S against FA-induced cytotoxicity, oxidative stress and apoptosis in PC12 cells. These findings provide a novel mechanism underlying the protection of H2S against FA-induced neurotoxicity.

Show MeSH
Related in: MedlinePlus