Abstract
The thesis of this review is that oxidative stress is the central factor in major depressive disorder (MDD) and Alzheimer’s disease (AD). The major elements involved are inflammatory cytokines, the hypothalamic–pituitary axis, the hypothalamic–pituitary gonadal, and arginine vasopressin systems, which induce glucocorticoid and “oxidopamatergic” cascades when triggered by psychosocial stress, severe life-threatening events, and mental-affective and somatic diseases. In individuals with a genomic vulnerability to depression, these cascades may result in chronic depression–anxiety–stress spectra, resulting in MDD and other known depressive syndromes. In contrast, in subjects with genomic vulnerability to AD, oxidative stress-induced brain damage triggers specific antioxidant defenses, i.e., increased levels of amyloid-β (Aβ) and aggregation of hyper-phosphorylated tau, resulting in paired helical filaments and impaired functions related to the ApoEε4 isoform, leading to complex pathological cascades culminating in AD. Surprisingly, all the AD-associated molecular pathways mentioned in this review have been shown to be similar or analogous to those found in depression, including structural damage, i.e., hippocampal and frontal cortex atrophy. Other interacting molecular signals, i.e., GSK-3β, convergent survival factors (brain-derived neurotrophic factor and heat shock proteins), and transition redox metals are also mentioned to emphasize the vast array of intermediates that could interact via comparable mechanisms in both MDD and AD.
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Abbreviations
- AD:
-
Alzheimer’s disease
- Aβ:
-
Amyloid-β
- ACTH:
-
Adrenal corticotrophic hormone
- AGE:
-
Advanced glycation end product
- ApoEε4:
-
Apolipoprotein Eε4
- AβPP:
-
Amyloid β protein precursor
- BDNF:
-
Brain-derived neurotrophic factor
- CSF:
-
Cerebral spinal fluid
- DNA:
-
Deoxyribonucleic acid
- GSK-3β:
-
Glycogen synthase kinase-β
- GRH:
-
Gonadotropin-releasing hormone
- G-Px:
-
Glutathione peroxidase
- 4-HNE:
-
4-hydroxy-nonenal
- HSP:
-
Heat shock protein
- 5-HTT:
-
Serotonin transporter
- IL-1β:
-
Interleucine-1β
- IFN-γ:
-
Interferon-γ
- IL-1:
-
Interleukin-1
- IL-6R:
-
Interleukin-6 receptor
- JAK:
-
Janus kinase
- JNK 1–3:
-
Jun NH2 kinases 1–3
- MAPK:
-
Mitogen-activated protein kinase
- MCI:
-
Mild cognitive impairment
- MDD:
-
Major depressive disorder
- NGF:
-
Nerve growth factor
- NFT:
-
Neurofibrillary tangle
- NMDA:
-
N-Methyl-dextro-aspartate
- NMDAR:
-
NMDA receptor
- NO:
-
Nitric oxide
- NSAID:
-
Non-steroidal anti-inflammatory drugs
- NSD:
-
Not senile dementia
- PET:
-
Positron emission tomography
- PKC:
-
Protein kinase C
- RNS:
-
Reactive nitrogen species
- ROS:
-
Reactive oxygen species
- SDAT:
-
Senile dementia of Alzheimer type
- SP:
-
Senile plaque
- Tau:
-
Tau protein
- TNF-ɑ:
-
Tumor necrosis factor-ɑ
- TRK-β:
-
Tyrosine-receptor kinase-β
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Acknowledgments
George Perry is supported by the Semmes Foundation, Inc.; the Alzheimer Association; and by a grant from the National Institute on Minority Health and Health Disparities (G12MD007591) from the National Institutes of Health.
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Rodrigues, R., Petersen, R.B. & Perry, G. Parallels Between Major Depressive Disorder and Alzheimer’s Disease: Role of Oxidative Stress and Genetic Vulnerability. Cell Mol Neurobiol 34, 925–949 (2014). https://doi.org/10.1007/s10571-014-0074-5
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DOI: https://doi.org/10.1007/s10571-014-0074-5