Carotenoid level

ASTLEY s B, ELLIOTT R M, ARCHER D B and souTHON s (2002) Increased cellular carotenoid levels reduce the persistance of DNA single strand breaks following oxidative chaUange. Nutrition and Cancer. In press. 

Table 13.4 Tomato mutants with altered carotenoid levels...

Based upon such reports, there is an increasing view that functional foods (nutraceuticals), in which carotenoid levels are high or modified qualitatively, would be beneficial to human health, especially with respect to degenerative... 

A single gene transformation crtB from Erwinia) was sufficient to increase carotenoid levels some 50-fold in seeds of canola (Brassica napus), which already contains low levels of carotenoids (Shewmaker et ah, 1999). This is the most spectacular increase in carotenoid levels of any plant to date. 

Health benefits of carotenoids are related to their bioavailability and thus then-absorption. Plasma concentration is considered a good biomarker of fruit and vegetable consumption. Table 3.1.1 shows plasma carotenoid levels in EPIC study subjects from 16 European locations. EPIC was the first large cross-sectional study analyzing plasma carotenoid levels in several European populations. ... 

Mean Plasma Carotenoid Levels (timol/l) in EPIC Study Subjects from... 

Both intact carotenoids and their apolar metabolites (retinyl esters) are secreted into the lymphatic system associated with CMs. In the blood circulation, CM particles undergo lipolysis, catalyzed by a lipoprotein lipase, resulting in the formation of CM remnants that are quickly taken up by the liver. In the liver, the remnant-associated carotenoid can be either (1) metabolized into vitamin A and other metabolites, (2) stored, (3) secreted with the bile, or (4) repackaged and released with VLDL particles. In the bloodstream, VLDLs are transformed to LDLs, and then HDLs by delipidation and the carotenoids associated with the lipoprotein particles are finally distributed to extrahepatic tissues (Figure 3.2.2). Time-course studies focusing on carotenoid appearances in different lipoprotein fractions after ingestion showed that CM carotenoid levels peak early (4 to 8 hr) whereas LDL and HDL carotenoid levels reach peaks later (16 to 24 hr). 

Raman measurements of skin carotenoid levels could be used as an indirect, rapid optical method to assess fruit and vegetable consumption in large populations. 

Also, we have noted that patients with unilateral cataracts after trauma or retinal detachment repair typically have very similar RRS carotenoid levels in the normal and in the pseudophakic eye. Thus, we have concluded that there is a decline of macular carotenoids that reaches a low steady state just at the time when the incidence and prevalence of AMD begins to rise dramatically. While this age effect has been noticed sometimes also in other studies using clinical populations and different MP detection methods (Sharifzadeh et al. 2006, Nolan et al. 2007), several groups have reported constant, age-independent MP levels. Examples include reflectance-based population studies in which respective average MP optical densities of 0.23 (Delori et al. 2001), 0.33 (Berendschot et al. 2002), and 0.48 (Berendschot and Van Norren 2004) were determined. 

To validate the skin carotenoid RRS detection approach, we initially carried out an indirect validation experiment that compared HPLC derived carotenoid levels of fasting serum with RRS derived carotenoid levels for inner palm tissue sites. Measuring a large group of 104 healthy male and female human volunteers, we obtained a significant correlation (p < 0.001) with a correlation coefficient of 0.78 (Smidt et al. 2004). Recently, we carried out a direct validation study, in which we compared in vivo RRS carotenoid skin responses with HPLC-derived results, using the thick... 

FIGURE 6.14 (a) Plot of carotenoid levels, shown as solid disks, for eight samples of human tissue mea-... 

Based on these capabilities, the RRS detection method has already found commercial application in the nutritional supplement industry (BioPhotonic Scanner , Pharmanex LLC, Provo, and Utah), which has placed thousands of portable instruments with their customers for rapid optical measurements of dermal carotenoid levels, and which has further developed the instrumentation for rugged field use (Bergeson et al. 2008). 

Bhosale P, Zhao DY, and Bernstein PS (2007), HPLC measurement of ocular carotenoid levels in human donor eyes in the lutein supplementation era, Invest. Ophthalmol. Visual Sci. 48 543-549. 

Obana, A., T. Hiramitsu et al. (2008). Macular carotenoid levels of normal subjects and age-related maculopathy patients in a Japanese population. Ophthalmology 115(1) 147-157. 

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