Vitamin B12 Attenuates Changes in Phospholipid Levels Related to Oxidative Stress in SH-SY5Y Cells

Abstract

Oxidative stress is closely linked to Alzheimer’s disease (AD), and is detected peripherally as well as in AD-vulnerable brain regions. Oxidative stress results from an imbalance between the generation and degradation of reactive oxidative species (ROS), leading to the oxidation of proteins, nucleic acids, and lipids. Extensive lipid changes have been found in post mortem AD brain tissue; these changes include the levels of total phospholipids, sphingomyelin, and ceramide, as well as plasmalogens, which are highly susceptible to oxidation because of their vinyl ether bond at the sn-1 position of the glycerol-backbone. Several lines of evidence indicate that a deficiency in the neurotropic vitamin B12 is linked with AD. In the present study, treatment of the neuroblastoma cell line SH-SY5Y with vitamin B12 resulted in elevated levels of phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, and plasmalogens. Vitamin B12 also protected plasmalogens from hydrogen peroxide (H2O2)-induced oxidative stress due to an elevated expression of the ROS-degrading enzymes superoxide-dismutase (SOD) and catalase (CAT). Furthermore, vitamin B12 elevates plasmalogen synthesis by increasing the expression of alkylglycerone phosphate synthase (AGPS) and choline phosphotransferase 1 (CHPT1) in SH-SY5Y cells exposed to H2O2-induced oxidative stress.

Simultaneous Intake of Chlorella and Ascidian Ethanolamine Plasmalogen Accelerates Activation of BDNF–TrkB–CREB Signaling in Rats

“…Kotake-Nara et al reported that intestinal absorption of carotenoids by Caco-2 cells, although low in general, was enhanced by glycerophospholipids in mixed micelles [ 37 ], suggesting that phospholipids containing plasmalogen promote lutein absorption. In addition, it has been reported that vitamin B12 promotes plasmalogen biosynthesis and protects plasmalogen from oxidative stress in neuroblastoma cells [ 38 ]. Chlorella powder used in this study contained 200 µg/100 g of vitamin B12 ( Table 1 ), and it is estimated that rats in the CHL and Mix groups consumed approximately 40% more vitamin B12 compared to rats in other groups.…”

Vitamin B12 Deficiency and the Nervous System: Beyond Metabolic Decompensation—Comparing Biological Models and Gaining New Insights into Molecular and Cellular Mechanisms

“…Specifically, when the cells were treated with hydrogen peroxide (H 2 O 2 ) to induce oxidative stress, the administration of VitB12 demonstrated a beneficial effect on the plasmalogens. This effect was attributed to the indirect antioxidant activity of VitB12, which upregulated the expression of superoxide dismutase (SOD) and catalase (CAT) enzymes responsible for degrading ROS [ 126 ]. A similar effect has been observed in melanocytes, where VitB12 (specifically Me-Cbl) can induce the activation of Nuclear factor erythroid 2-related factor 2 (NRF2), subsequently promoting the transcription of target genes SOD and CAT , and reducing oxidative stress triggered by H 2 O 2 [ 127 ].…”

“…In SH-SY5Y cells, VitB12 enhanced the synthesis of plasmalogens by promoting the expression of alkylglycerone phosphate synthase (AGPS) and choline phosphotransferase1 (CHPT1) [ 126 ], suggesting an impact of VitB12 on cell lipid composition. Interestingly, comparing the works of Theiss and Zhong (both were carried out using SH-SY5Y cells), it is to be noted that Theiss and coworkers employed VitB12 at a dose of 10 nM, which was indeed contrasting compared to the 20 mM concentration of VitB12 utilized by Zhong and co-workers.…”

Alzheimer’s Disease Treatment: The Search for a Breakthrough

“…Vitamin B12 plays a role in the cellular metabolism of carbohydrates, proteins and lipids, and its deficiency has neurologic consequences that can include cognitive decline [ 309 , 310 , 311 ]. In addition, vitamin B12 has anti-oxidant properties postulated to be neuroprotective [ 312 ]. Politis et al found an association between low serum B12 and higher peripheral blood mononuclear cell production of Il-6, an inflammatory cytokine [ 313 ].…”