Homo-Tris-Nitrones Derived from α-Phenyl-N-tert-butylnitrone: Synthesis, Neuroprotection and Antioxidant Properties
Abstract
:1. Introduction
2. Results and Discussion
2.1. Chemistry
2.2. Neuroprotection Studies of HTNs 1-3
2.2.1. Neuroprotection Analysis in an Oligomycin A/Rotenone Model
2.2.2. Neuroprotection Analysis in an Oxygen Glucose Deprivation Model
2.2.3. Effect of HTNs on Necrotic and Apoptotic Cell Death Induced by Induced by Oxygen Glucose Deprivation
2.2.4. Basal Neurotoxicity of HTNs 1-3
2.2.5. Antioxidant Capacity of HTNs 1-3. Production and Scavenging of Radical Superoxide Radical in Human Neuroblastoma SH-SY5Y Cells
2.3. Antioxidant Tests
3. Materials and Methods
3.1. Chemistry
3.1.1. General Methods
3.1.2. General Method for the Synthesis of HTNs
3.1.3. (1. Z,1′Z,1″Z)-1,1′,1″-(Benzene-1,3,5-triyl)tris(N-methylmethanimine oxide) (HTN1)
3.1.4. (1. Z,1′Z,1″Z)-1,1′,1″-(Benzene-1,3,5-triyl)tris(N-tert-butylmethanimine oxide) (HTN2)
3.1.5. (1. Z,1′Z,1″Z)-1,1′,1″-(Benzene-1,3,5-triyl)tris(N-benzylmethanimine oxide) (HTN3)
3.2. Neuroprotection Assessment Assays
3.2.1. Neuroblastoma Cell Cultures
3.2.2. Neuroblastoma Cell Cultures Exposure to Oxygen Glucose Deprivation
3.2.3. Assessment of Cell Viability
3.2.4. Measurement of LDH Activity
3.2.5. Analysis of Caspase-3 Activity
3.2.6. Measurement of Reactive Oxygen Species Formation
3.2.7. Statistical Analysis
3.3. Antioxidant Activity Tests of HTNs 1-3, PBN, Trolox, and NDGA in Vitro
3.3.1. Estimation of Lipophilicity as Clog P
3.3.2. General Methods
3.3.3. Inhibition of Linoleic Acid Peroxidation
3.3.4. Soybean Lipoxygenase Inhibition Study
3.3.5. ABTS+•—Decolorization Assay for Antioxidant Activity
3.3.6. Hydroxyl Radical Scavenging Activity
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
Abbreviations
AAPH | 2,2′-Azobis(2-amidinopropane) dihydrochloride |
NAC | N-Acetyl-L-cysteine |
BBB | Blood−brain barrier |
HBNs | Homo-bis-nitrones |
HTNs | Homo-tris-nitrones |
IR | Ischemic reperfusion |
LDH | Lactate dehydrogenase |
LOX | Lipoxygenase |
LP | Lipid peroxidation |
MTT | 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide |
NDGA | Nordihydroguaiaretic acid |
O/R | Oligomycin A/Rotenone |
OGD | Oxygen Glucose Deprivation |
PBN | α-Phenyl-N-tert-butylnitrone |
ROS | Reactive oxygen species |
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Nitrones/ Standards | ClogP * | ILPO (%) | LOX Inhibition (% or IC50 [μM]) (±SEM) | Scavenger Activity for •OH (%) | ABTS+. (%) |
---|---|---|---|---|---|
HTN1 | −2.94 | 46 | 100 ± 1.1 μΜ | 59 | No |
HTN2 | 0.77 | 55 | 26 ± 0.2% | 81 | No |
HTN3 | 2.73 | 92 | 70 ± 2.6 μΜ | 83 | 10 |
PBN | 3.02 | 11 | 23 ± 0.1% | No | 5 |
HBN5 [46] | 4.51 | 55 | 6 ± 0.1% | 67 | No |
HBN6 [46] | 4.96 | 37 | 29 ± 0.3% | 81 | No |
NDGA | 0.45 μM | ||||
Trolox | 88 | 83 | 91 |
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Diez-Iriepa, D.; Chamorro, B.; Talaván, M.; Chioua, M.; Iriepa, I.; Hadjipavlou-Litina, D.; López-Muñoz, F.; Marco-Contelles, J.; Oset-Gasque, M.J. Homo-Tris-Nitrones Derived from α-Phenyl-N-tert-butylnitrone: Synthesis, Neuroprotection and Antioxidant Properties. Int. J. Mol. Sci. 2020, 21, 7949. https://doi.org/10.3390/ijms21217949
Diez-Iriepa D, Chamorro B, Talaván M, Chioua M, Iriepa I, Hadjipavlou-Litina D, López-Muñoz F, Marco-Contelles J, Oset-Gasque MJ. Homo-Tris-Nitrones Derived from α-Phenyl-N-tert-butylnitrone: Synthesis, Neuroprotection and Antioxidant Properties. International Journal of Molecular Sciences. 2020; 21(21):7949. https://doi.org/10.3390/ijms21217949
Chicago/Turabian StyleDiez-Iriepa, Daniel, Beatriz Chamorro, Marta Talaván, Mourad Chioua, Isabel Iriepa, Dimitra Hadjipavlou-Litina, Francisco López-Muñoz, José Marco-Contelles, and María Jesús Oset-Gasque. 2020. "Homo-Tris-Nitrones Derived from α-Phenyl-N-tert-butylnitrone: Synthesis, Neuroprotection and Antioxidant Properties" International Journal of Molecular Sciences 21, no. 21: 7949. https://doi.org/10.3390/ijms21217949