Alzheimer's and Oxidized Cholesterol

I have mentioned many times that oxidized cholesterol is 500 times more atherogenic or promotional of blocked arteries than non-oxidized cholesterol. Recently, researchers have begun to note that oxidation of cholesterol and other fats in the brain is associated with the development of Alzheimer's disease. A study by Testa concludes, "these results strongly support the association between changes in oxysterol levels and AD progression." Research by Marwarha suggests that oxidized cholesterol also plays a role in the development of Parkinson's disease. Measuring oxidation products in the spinal fluid can ever serve as a marker for the development of Alzheimer's and impairment of brain function.

Non oxidized cholesterol does not appear to cross the blood-brain barrier, but oxidized cholesterol can. It then can promote inflammation of the nerves and brain cells that leads to brain deterioration. Oxidized fats are hard on the brain and can lead to death of brain cells.

Oxidized cholesterol can enter the body through a diet high in oxidized fats. The cholesterol within the body can also oxidize, particularly if the diet is deficient in fat and water soluble antioxidants. Key fat soluble antioxidants include carotenoids, CoQ10, and vitamin E. Research on the NeoLife Carotenoid Complex suggested that it significantly reduced fat oxidation in the blood when levels were high due to poor diet. Water soluble antioxidants like vitamin C, tea, and berries can also reduce the risk of auto-oxidation of fats in the brain.

Sources of oxidized fats in the diet include highly heated fats in fast food, powdered eggs and aged cheeses.

References:

Testa G, et al. Changes in brain oxysterols at different stages of Alzheimer's disease: Their involvement in neuroinflammation. Redox Biol. 2016 Dec;10:24-33. doi: 10.1016/j.redox.2016.09.001. Epub 2016 Sep 16. PMID: 27687218; PMCID: PMC5040635.

Marwarha G, Ghribi O. Does the oxysterol 27-hydroxycholesterol underlie Alzheimer's disease-Parkinson's disease overlap? Exp Gerontol. 2015 Aug;68:13-8. doi: 10.1016/j.exger.2014.09.013. Epub 2014 Sep 28. PMID: 25261765; PMCID: PMC4377123.

Wang HL, et al. Cholesterol, 24-Hydroxycholesterol, and 27-Hydroxycholesterol as Surrogate Biomarkers in Cerebrospinal Fluid in Mild Cognitive Impairment and Alzheimer's Disease: A Meta-Analysis. J Alzheimers Dis. 2016;51(1):45-55. doi: 10.3233/JAD-150734. PMID: 26836015; PMCID: PMC6110663.

Gamba P, et al. Oxidized cholesterol as the driving force behind the development of Alzheimer's disease. Front Aging Neurosci. 2015 Jun 19;7:119. doi: 10.3389/fnagi.2015.00119. PMID: 26150787; PMCID: PMC4473000.