Plasma levels of HDL and carotenoids are lower in dementia patients with vascular comorbidities.
Elevated serum cholesterol concentrations in mid-life increase risk for Alzheimer’s disease (AD) in later life. However, lower concentrations of cholesterol-carrying high density lipoprotein (HDL) and its principal apolipoprotein A1 (ApoA1) correlate with increased risk for AD. As HDL transports oxocarotenoids, which are scavengers of peroxynitrite, we have investigated the hypothesis that lower HDL and oxocarotenoid concentrations during AD may render HDL susceptible to nitration and oxidation and in turn reduce the efficiency of reverse cholesterol transport (RCT) from lipid-laden cells. Fasting blood samples were obtained from subjects with (1) AD without cardiovascular comorbidities and risk factors (AD); (2) AD with cardiovascular comorbidities and risk factors (AD Plus); (3) normal cognitive function; for carotenoid determination by HPLC, analysis of HDL nitration and oxidation by ELISA, and 3H-cholesterol export to isolated HDL. HDL concentration in the plasma from AD Plus patients was significantly lower compared to AD or control subject HDL levels.
Similarly, lutein, lycopene, and zeaxanthin concentrations were significantly lower in AD Plus patients compared to those in control subjects or AD patients, and oxocarotenoid concentrations correlated with Mini-Mental State Examination scores. At equivalent concentrations of ApoA1, HDL isolated from all subjects irrespective of diagnosis was equally effective at mediating RCT. HDL concentration is lower in AD Plus patients’ plasma and thus capacity for RCT is compromised. In contrast, HDL from patients with AD-only was not different in concentration, modifications, or function from HDL of healthy age-matched donors.
The relative importance of elevating HDL alone compared with elevating carotenoids alone or elevating both to reduce risk for dementia should be investigated in patients with early signs of dementia.
Lycopene for the Prevention or Treatment of Prostate Disease
Benign prostatic hyperplasia (BPH) and prostate cancer are common diseases of the prostate gland. BPH is commonly treated by pharmaceutical products, which commonly improve symptoms but are often off-set by adverse events including erectile dysfunction, which affect quality of life. Similarly, a variety of treatment options exist for the treatment of prostate cancer. The applicability of these prostate cancer treatments is reliant on stage of disease. Whilst effectiveness of prostate cancer treatments may vary, common adverse effects include erectile dysfunction, incontinence and lower quality of life. Early evidence from systematic reviews has suggested that diet and lifestyle factors may be beneficial in reducing the risk of cancer.
Lycopene, a member of the carotenoid family, found commonly in red pigmented fruit and vegetables has been established as having strong antioxidant and pro-oxidant properties. This chapter examines the current evidence on the use of lycopene as a preventive agent for prostate disease