Cadmium Impairs Autophagy Leading to Apoptosis by Ca2+-Dependent Activation of JNK Signaling Pathway in Neuronal Cells

Autophagy, a process for self-degradation of intracellular components and dysfunctional organelles, is closely related with neurodegenerative diseases. It has been shown that cadmium (Cd) induces neurotoxicity partly by impairing autophagy. However, the underlying mechanism is not fully elucidated. In this study, we show that Cd induced expansion of autophagosomes with a concomitant abnormal expression of autophagy-related (Atg) proteins in PC12 cells and primary murine neurons. 3-MA, a classical inhibitor of autophagy, attenuated Cd-induced expansion of autophagosomes and apoptosis in the cells. Further investigation demonstrated that Cd activated JNK pathway contributing to autophagosome expansion-dependent neuronal apoptosis. This is supported by the findings that pharmacological inhibition of JNK with SP600125 or expression of dominant negative c-Jun markedly attenuated Cd-induced expansion of autophagosomes and abnormal expression of Atg proteins, as well as apoptosis in PC12 cells and/or primary neurons. Furthermore, we noticed that chelating intracellular free Ca2+ ([Ca2+]i) with BAPTA/AM profoundly blocked Cd-elicited activation of JNK pathway and consequential expansion of autophagosomes, abnormal expression of Atg proteins, and apoptosis in the neuronal cells. Similar events were also seen following prevention of [Ca2+]i elevation with EGTA or 2-APB, implying a Ca2+-dependent mechanism involved. Taken together, the results indicate that Cd impairs autophagy leading to apoptosis by Ca2+-dependent activation of JNK signaling pathway in neuronal cells. Our findings highlight that manipulation of intracellular Ca2+ level and/or JNK activity to ameliorate autophagy may be a promising intervention against Cd-induced neurotoxicity and neurodegeneration.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:46

Enthalten in:

Neurochemical research - 46(2021), 8 vom: 22. Aug., Seite 2033-2045

Sprache:

Englisch

Beteiligte Personen:

Xu, Chong [VerfasserIn]
Chen, Sujuan [VerfasserIn]
Xu, Ming [VerfasserIn]
Chen, Xiaoling [VerfasserIn]
Wang, Xiaoxue [VerfasserIn]
Zhang, Hai [VerfasserIn]
Dong, Xiaoqing [VerfasserIn]
Zhang, Ruijie [VerfasserIn]
Chen, Xin [VerfasserIn]
Gao, Wei [VerfasserIn]
Huang, Shile [VerfasserIn]
Chen, Long [VerfasserIn]

Links:

Volltext

Themen:

00BH33GNGH
1TW30Y2766
3-methyladenine
5142-23-4
Adenine
Anthracenes
Apoptosis
Autophagy
Autophagy-Related Proteins
Cadmium
Calcium
Calcium ion
JAC85A2161
JNK
Journal Article
Neuronal cells
Pyrazolanthrone
SY7Q814VUP

Anmerkungen:

Date Completed 18.10.2021

Date Revised 02.08.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1007/s11064-021-03341-x

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM325712204