Skin Carotenoid Levels Research Articles

Resonance Raman based skin carotenoid measurements in newborns and infants.

We describe Resonance Raman based skin carotenoid measurements in newborns and infants. Skin- and serum carotenoid levels correlate with high statistical significance in healthy newborns and infants, and with reduced accuracy also in prematurely born infants, who in general feature very low carotenoid levels and thin transparent skin giving rise to large background absorption effects. Skin carotenoid levels can be easily compared among subjects and/or tracked in longitudinal studies with the highly molecule-specific Raman method. It therefore holds promise as a rapid, non-invasive, carotenoid antioxidant assessment method for newborns and infants in the field of pediatrics.

Skin carotenoid levels may not reflect vitamin A (retinol) levels

To the Editor: We read with interest the letter entitled “Skin carotenoid levels are not associated with risk of nonmelanoma skin cancer.” The goal of this small pilot study was to compare mean skin carotenoid levels among 23 patients with a history of basal cell carcinoma (BCC), 22 patients with a history of squamous cell carcinoma (SCC), and 36 patients with no nonmelanoma skin cancer (NMSC) history, and the differences were not found to be statistically significant. Whereas the lack of statistical significance may be due to the lack of power in the study (as mentioned by the authors), as well as other methodologic issues (no adjustment for potential confounding variables such as age, gender, and ethnicity which may impact risk of BCC, SCC, and skin carotenoid levels; no information on the timing of the NMSC diagnosis in relation to the skin carotenoid measurement), the results are, nonetheless, intriguing.

Skin carotenoid levels are not associated with risk of nonmelanoma skin cancer: Response to “Supplement use and the risk of cutaneous squamous cell carcinoma”

To the Editor: Carotenoids, vitamin A provitamins found in several foods and oral supplements, have antioxidant and photoprotective properties and may confer protection against nonmelanoma skin cancer with less associated toxicity than systemic retinoids.1 However, study findings to date, including those of the study “Supplement use and the risk of cutaneous squamous cell carcinoma”, have failed to provide strong evidence for the anticancer effects of these chemical compounds.2-5

Relationship between skin carotenoid level and metabolic syndrome related indices

To provide scientific rationales through an analysis of the relationship between skin carotenoid level and metabolic syndrome related indices so as to prevent the occurrences of metabolic syndrome (MS). A total of 493 cases from December 2010 to December 2011 were recruited to measure the skin carotenoid levels and various laboratory indices of metabolic syndrome. Along with the rising risk factors of MS, the skin carotenoid level declined. And there were significant differences between the normal group (n=103), low risk group (n=63), high risk group (n=172) and the MS group (n=155) (40,407±10,961, 28,396±8683, 28,523±8887, 23,303±8887, F=72.704, P<0.01). Gender and skin carotenoid level had an obvious correlation. Males were significantly lower in females (P<0.01). There was no correlation of age and skin carotenoid level (P>0.05). Skin carotenoid level and metabolic syndrome have a negative correlation. Measurement of skin carotenoid level plays a certain role in the prevention of metabolic syndrome.

Macular Pigment Imaging in AREDS2 Participants: An Ancillary Study of AREDS2 Subjects Enrolled at the Moran Eye Center

Age-Related Eye Disease Study 2 (AREDS2) is a randomized, placebo-controlled study designed to determine whether supplementation with 10 mg of lutein and 2 mg of zeaxanthin per day can slow the rate of progression of age-related macular degeneration (AMD). Although some biomarkers of response to carotenoid supplementation such as serum concentrations are part of the AREDS2 protocol, measurement of carotenoid concentrations in the eye and other tissues is not. In this approved ancillary study, macular pigment optical density (MPOD), macular pigment distributions, and skin carotenoid levels at enrollment and at each annual visit were measured to assess baseline carotenoid status and to monitor response to assigned interventions. All subjects enrolled at the Moran Eye Center had MPOD and macular pigment spatial distributions measured by dual-wavelength autofluorescence imaging and total skin carotenoids measured by resonance Raman spectroscopy. Results. Baseline MPOD in enrolled subjects was unusually high relative to an age-matched control group that did not consume carotenoid supplements regularly, consistent with the high rate of habitual lutein and zeaxanthin consumption in Utah AREDS2 subjects prior to enrollment. MPOD did not correlate with serum or skin carotenoid measurements. Useful information is provided through this ancillary study on the ocular carotenoid status of AREDS2 participants in the target tissue of lutein and zeaxanthin supplementation: The macula. When treatment assignments are unmasked at the conclusion of the study, unique tissue-based insights will be provided on the progression of AMD in response to long-term, high-dose carotenoid supplementation versus diet alone. (ClinicalTrials.gov number, NCT00345176.).

Cover Picture: J. Biophotonics 7/2012

AbstractThe cover illustrates the measurement of human skin carotenoid levels based on pressure mediated reflection spectroscopy. Carotenoids have a widespread distribution in fruits and vegetables, are taken up through the diet, and play an important role in tissue health through their function as antioxidants. Their characteristic absorption in the blue/green spectral range can be quantified in human tissue such as the thumb and tracked upon dietary supplementation. (Picture: I. V. Ermakov and W. Gellermann, pp. 442–453, in this issue)

Improvement in Skin Carotenoid Levels Assessed by Reflectance Spectroscopy

BACKGROUNDCarotenoids have been directly associated with health benefits, including lutein (eye health), lycopene (cardiovascular and prostate health), and beta‐carotene (ultraviolet skin protection). Various biophotonic spectroscopy techniques are accurate and noninvasive methods of detecting skin carotenoid levels and assessing change in antioxidant levels over time.OBJECTIVEWe used Reflectance Spectroscopy to measure skin carotenoid levels following two supplementation regimens.METHODSSixty‐six healthy volunteers were supplemented with: Group A = 15mg/day of mixed carotenoids (9mg beta‐carotene, 4mg lycopene, and 2mg lutein in a proprietary nano‐emulsion); Group B = 18mg/day of natural beta‐carotene; or Group C = placebo containing no carotenoids. Skin carotenoid levels were measured at Baseline and Weeks 8 &amp; 16.RESULTSSkin carotenoid levels were increased 59% and 57% in Group A, and 37% and 36% in Group B at weeks 8 and 16, respectively, compared to Control.CONCLUSIONThese results show, via Reflectance Spectroscopy, that skin carotenoid levels are significantly increased by supplementation with natural beta‐carotene (18mg/d) or a proprietary nano‐emulsion (15mg/d). The magnitude of skin carotenoid increase was greater with the nano‐emulsion, suggesting a possible enhancement of absorption, delivery, deposition, or retention in the body.

Carotenoids Intake and Asthma Prevalence in Thai Children

Several antioxidant nutrients have been described to inversely correlate with asthma. In order to quantify the intake of these substances, it is possible to measure skin levels by Raman spectroscopy, a novel non-invasive technique that can also be used in children. This cross-sectional school-based study involved 423 children from a rural area of Thailand. Asthmatic children were diagnosed according to a Health Interview for Asthma Control questionnaire. Skin carotenoid levels were measured with Raman spectroscopy. Demographic data were obtained by directly interviewing children and their parents, whereas anthropometric parameters were measured by trained staff. Intake of carotenoids, vitamin A and C were evaluated by a food frequency questionnaire. Overall incidence of asthma in Thai schoolchildren (aged 3.5–17.8 years) was 17.3%. There was no significant difference in dietary intake of carotenoids and vitamin A and C, and skin carotenoid level between asthmatic and non-asthmatic children. Skin carotenoid level significantly correlated with all carotenoids and vitamin A intake (P<0.05). Carotenoids and vitamin A and C intakes, and skin carotenoid levels were not associated with the risk of asthma in Thai children. Skin carotenoids correlated with all carotenoids and vitamin A intake in mild to moderate degrees. Raman spectroscopy was confirmed to be a useful tool to determine antioxidant skin levels.

Dermal carotenoid measurements via pressure mediated reflection spectroscopy

We describe a reflection-based method for the quantitative detection of carotenoid antioxidants in living human skin. The skin tissue site of interest is illuminated with broad-band white light spanning the spectral range from 350-850 nm and the spectral composition of the diffusively reflected light is analyzed in real time. Topical pressure is applied to temporarily squeeze blood out of the illuminated tissue volume. In this way the influence of oxy-hemoglobin on the reflection spectra is effectively reduced. After a short optical clearing time the carotenoid absorption becomes easily discernable in a 460-500 nm spectral window and its optical density can be calculated with high accuracy. Our empirical methodology provides a non-invasive rapid determination of skin carotenoid levels, can be used to monitor skin carotenoid concentration changes over time in response to carotenoid containing natural or supplemental diets, and is easily adaptable for applications in clinical and field settings.

Skin carotenoid levels in adult patients with psoriasis

Psoriasis is an inflammatory disease that not only affects the skin but can also have systemic implications such as obesity and nutritional deficiencies. Carotenoids are vitamin A provitamins with anti-oxidant properties that are present in human tissues including skin. To determine whether psoriasis is associated with lower levels of skin carotenoid levels. In this cross-sectional study, skin carotenoid levels were measured on the palms of 44 patients with psoriasis and 72 patients without psoriasis. A linear regression model was used to evaluate the relationship between psoriasis and carotenoid levels (primary aim) and to determine if severity of disease was associated with carotenoid levels (secondary aim). Potential confounders included demographic factors, smoking status, body mass index and multivitamin intake. The mean carotenoid levels in the psoriasis and no psoriasis groups were respectively 22,099 and 29,180 and presence of psoriasis was found to be significantly related to lower levels of carotenoids in both univariable and multivariable analysis (P < 0.05). In the psoriasis group, the Psoriasis Area and Severity Index score was not significantly related to carotenoid levels (P = 0.07). Patients with psoriasis appear to have lower skin carotenoid counts than patients without psoriasis.

Evaluation of carotenoid level in schizophrenic patients using non-invasive measurement

Free radicals are produced as part of the body immune response triggered by exogenous oxidants. In excess, they impair antioxidant defence system and cause oxidative stress. Antioxidants are hypothesised as antidotes to counteract oxidative stress and improve immune function. Carotenoids serve as a reliable indicator of overall antioxidant level in humans. This study investigated the possible relationship of carotenoid antioxidant levels in schizophrenia. A total of 351 schizophrenic subjects from Hospital Bahagia Ulu Kinta, Malaysia and 247 healthy controls were recruited. Subjects’ skin carotenoid levels were measured using a non-invasive technique, Raman spectroscopy. The results showed significant ( P < 0.01) reduction of carotenoid level in patient compared to healthy controls, suggesting higher levels of oxidative stress in schizophrenia. Comparison between gender, age, subtypes, antipsychotic drug treatments, and duration of illness was investigated, but none was significantly associated with carotenoid score. Antipsychotics were suggested to be the possible causes of reduced antioxidant level in schizophrenia.

Validation model for Raman based skin carotenoid detection

Raman spectroscopy holds promise as a rapid objective non-invasive optical method for the detection of carotenoid compounds in human tissue in vivo. Carotenoids are of interest due to their functions as antioxidants and/or optical absorbers of phototoxic light at deep blue and near UV wavelengths. In the macular region of the human retina, carotenoids may prevent or delay the onset of age-related tissue degeneration. In human skin, they may help prevent premature skin aging, and are possibly involved in the prevention of certain skin cancers. Furthermore, since carotenoids exist in high concentrations in a wide variety of fruits and vegetables, and are routinely taken up by the human body through the diet, skin carotenoid levels may serve as an objective biomarker for fruit and vegetable intake. Before the Raman method can be accepted as a widespread optical alternative for carotenoid measurements, direct validation studies are needed to compare it with the gold standard of high performance liquid chromatography. This is because the tissue Raman response is in general accompanied by a host of other optical processes which have to be taken into account. In skin, the most prominent is strongly diffusive, non-Raman scattering, leading to relatively shallow light penetration of the blue/green excitation light required for resonant Raman detection of carotenoids. Also, sizable light attenuation exists due to the combined absorption from collagen, porphyrin, hemoglobin, and melanin chromophores, and additional fluorescence is generated by collagen and porphyrins. In this study, we investigate for the first time the direct correlation of in vivo skin tissue carotenoid Raman measurements with subsequent chromatography derived carotenoid concentrations. As tissue site we use heel skin, in which the stratum corneum layer thickness exceeds the light penetration depth, which is free of optically confounding chromophores, which can be easily optically accessed for in vivo RRS measurement, and which can be easily removed for subsequent biochemical measurements. Excellent correlation (coefficient R = 0.95) is obtained for this tissue site which could serve as a model site for scaled up future validation studies of large populations. The obtained results provide proof that resonance Raman spectroscopy is a valid non-invasive objective methodology for the quantitative assessment of carotenoid antioxidants in human skin in vivo.

Effects of antioxidant supplementation on skin and serum carotenoids

Raman spectroscopy (RS) has been used to determine human carotenoid status based on non-invasive skin measurements. In this study, we compared RS with serum HPLC to monitor effects of a comprehensive dietary vitamin/mineral/antioxidant supplement (LifePak, Pharmanex). Fifty-three healthy adults (age 55.4±8.4 yrs) were randomly assigned in a 42-day double-blind study to assess the effects of the dietary supplement (S: n=25) vs placebo (P: n=28) on serum carotenoids and antioxidant status. Serum carotenoids were determined using HPLC. Skin carotenoids were assessed using RS (Pharmanex BioPhotonic Scanner) using 473 nm excitation in stratum corneum layer of a standardized location on the palm. Significant increases (p<0.05) were observed with S for total serum carotenoids (2.48 ± 1.1 to 3.35±1.6 ìmol/L), serum β-carotene (0.56 ± 0.3 to 1.26 ± 0.6 ìmol/L), lutein (0.29 ± 0.1 to 0.34 ± 0.1 ìmol/L), lycopene (0.94 ± 0.3 to 1.31 ± 0.4 ìmol/L), ascorbate (50 ± 23 to 85 ± 29 ìmol/L), α-tocopherol (34 ± 9.4 to 54 ± 13 ìmol/L) and skin carotenoids (18353 ± 4827 to 25358 ± 5229 units). Only serum ascorbate changed in P (53 ± 24 to 67 ± 39 ìmol/L). Significant correlations (p<0.01) between total serum and skin carotenoids were observed in S (baseline: r= 0.73; day 42: r= 0.57) and in P (baseline: r= 0.91; day 42: r= 0.87). The significant correlations between serum and skin carotenoid levels suggest that RS may be useful as an effective non-invasive tool to monitor carotenoid and possibly antioxidant status during dietary antioxidant interventions. Bioavailable carotenoids and other antioxidants were provided by LifePak.

Adiposity Negatively Influences Carotenoids and Antioxidant Status in Overweight Individuals.

2077 PURPOSE: To describe the cross-sectional association of body composition with carotenoid antioxidants in overweight individuals in 176 overweight (BMI ≥ 27 kg.M-2) participants. METHODS: Carotenoid antioxidant concentration in the skin was measured non-invasively using Raman Spectroscopy (Biophotonic Scanner, Pharmanex). Briefly, by shining a low power blue laser onto the skin at the palm of the hand an individual's carotenoid antioxidant levels were determined. Body composition (i.e., percent fat, fat mass, lean body mass) was determined with air displacement plethesmography. Data were analyzed using SPSS version 9.0. Statistical significance was set at p<0.05. RESULTS: Skin carotenoid level was inversely correlated with body weight (r = −0.228, p = 0.002), BMI (r = −0.176, p = 0.019), and fat mass (r = −0.228, p = 0.002). However correlations with Lean Body Mass (r = −0.121, p = 0.109) and percent fat (r = −0.092, p = 0.223) were not significant. CONCLUSIONS: This study confirms that in overweight and obese individuals the level of adipose tissue accumulation negatively influences skin carotenoid levels, and thus antioxidant status. A component of the known adverse health consequences from excess adiposity may thus arise from free radical damage to tissues. Effective strategies to support antioxidant status may be appropriate for overweight and obese individuals. Future studies should examine the effect of weight loss on carotenoid antioxidant concentration.

Supplementation with β-Carotene or a Similar Amount of Mixed Carotenoids Protects Humans from UV-Induced Erythema

Carotenoids are useful oral sun protectants, and supplementation with high doses of beta-carotene protects against UV-induced erythema formation. We compared the erythema-protective effect of beta-carotene (24 mg/d from an algal source) to that of 24 mg/d of a carotenoid mix consisting of the three main dietary carotenoids, beta-carotene, lutein and lycopene (8 mg/d each). In a placebo-controlled, parallel study design, volunteers with skin type II (n = 12 in each group) received beta-carotene, the carotenoid mix or placebo for 12 wk. Carotenoid levels in serum and skin (palm of the hand), as well as erythema intensity before and 24 h after irradiation with a solar light simulator were measured at baseline and after 6 and 12 wk of treatment. Serum beta-carotene concentration increased three- to fourfold (P < 0.001) in the beta-carotene group, whereas in the mixed carotenoid group, the serum concentration of each of the three carotenoids increased one- to threefold (P < 0.001). No changes occurred in the control group. The intake of either beta-carotene or a mixture of carotenoids similarly increased total carotenoids in skin from wk 0 to wk 12. No changes in total carotenoids in skin occurred in the control group. The intensity of erythema 24 h after irradiation was diminished in both groups that received carotenoids and was significantly lower than baseline after 12 wk of supplementation. Long-term supplementation for 12 wk with 24 mg/d of a carotenoid mix supplying similar amounts of beta-carotene, lutein and lycopene ameliorates UV-induced erythema in humans; the effect is comparable to daily treatment with 24 mg of beta-carotene alone.

Dietary Carotenoids Contribute to Normal Human Skin Color and UV Photosensitivity

The aim of the current study was to determine whether dietary carotenoids influence skin pigmentation and UV photosensitivity in a healthy unsupplemented panel (n = 22) of Caucasian (skin Type II) subjects. Skin spectrophotometric and tristimulus (L*a*b*) CR200 chromameter readings were made at various body sites to objectively measure skin carotenoid levels and skin color, respectively. The minimal erythemal dose (MED) was also measured to determine the intrinsic UV photosensitivity of the skin. We found that tristimulus b* values (but not L* and a* values) were consistently and closely correlated with skin carotenoid levels at a number of body sites including the back (r = 0.85, P < 0.00001), forehead (r = 0.85, P < 0.00001), inner forearm (r = 0.75, P < 0.0001) and palm of the hand (r = 0.78, P < 0.0001). Skin carotenoid levels and MED were also correlated in these subjects (r = 0.66, P < 0.001), as were tristimulus b* values and MED (r = 0.71, P < 0.0002). From these observations, we conclude that carotenoids from a normal, unsupplemented diet accumulate in the skin and confer a measurable photoprotective benefit (at least in lightly pigmented Caucasian skin), that is directly linked to their concentration in the tissue. Carotenoids also appear to contribute measurably and significantly to normal human skin color, in particular the appearance of "yellowness" as defined objectively by CR200 tristimulus b* values. On the basis of these findings we believe that objective measurements of skin color, in particular tristimulus b* values, may be a potentially useful means of monitoring dietary carotenoid status and assessing UV photosensitivity in Caucasian populations.

Carotenoids and carotenoids plus vitamin E protect against ultraviolet light–induced erythema in humans

Carotenoids and tocopherols, known to be efficient antioxidants and capable of scavenging reactive oxygen species generated during photooxidative stress, may protect the skin from ultraviolet light-induced erythema. beta-Carotene is widely used as an oral sun protectant but studies on its protective effects are scarce. The objective of this study was to investigate the protective effects of oral supplementation with carotenoids and a combination of carotenoids and vitamin E against the development of erythema in humans. A carotenoid supplement (25 mg total carotenoids/d) and a combination of the carotenoid supplement and vitamin E [335 mg (500 IU) RRR-alpha-tocopherol/d] were given for 12 wk to healthy volunteers. Erythema was induced by illumination with a blue-light solar simulator. Serum beta-carotene and alpha-tocopherol concentrations and skin carotenoid levels were assessed by HPLC and reflection photometry. Serum beta-carotene and alpha-tocopherol concentrations increased with supplementation. Erythema on dorsal skin (back) was significantly diminished (P < 0.01) after week 8, and erythema suppression was greater with the combination of carotenoids and vitamin E than with carotenoids alone. The antioxidants used in this study provided protection against erythema in humans and may be useful for diminishing sensitivity to ultraviolet light.

Physiological correlates of paternal care in male threespine stickleback

In threespine stickleback, Gasterosteus aculeatus, paternal care of eggs requires nesting males to remain in their territories to defend their nests from intruding males or bands of marauding females, thus decreasing feeding opportunities, which presumably leads to reserve mobilisation. To evaluate whether physiological consequences of paternal care are apparent in stickleback nesting in their breeding grounds, we examined whether males which were tending eggs (paternal males) differed in their physiological capacities from males without eggs in their nests (bachelor males). As female choice of males and nest sites could influence which males obtain matings, we also examined whether externally visible indicators of male quality (ectoparasite infestation, coloration and skin carotenoid content) and nest site quality (algal cover) are related to the physiological attributes of the nesting males. We examined biochemical correlates of burst and endurance swimming, as well as energy reserves and tissue masses. The physiological attributes varied little between paternal and bachelor males, suggesting limited costs of parental care. However, the number of eggs in the nests was negatively correlated with the dry mass of the axial musculature, suggesting reserve mobilisation during parental care. The number of eggs was positively correlated with the activity of pyruvate kinase in the pectoral muscle. The nests of paternal males had greater algal cover than those of bachelor males. The percent algal cover of a nest was positively correlated with the nesting male’s skin carotenoid levels. In contrast, the males whose nests had greater algal cover had lower total and soluble protein levels in the axial muscle. The coloration of the males at the time of capture was positively correlated with the activity of creatine phosphokinase (CPK) in the pectoral and axial muscles, but did not reflect condition, ectoparasite infestation, tissue masses or water contents. Skin carotenoid levels were positively correlated with the activity of CPK and LDH in the pectoral muscle as well as with that of CPK in the axial muscle, without reflecting energy reserves. Of the tissue masses, only the wet and dry masses of the kidney were correlated (negatively) with carotenoid levels. Whereas the externally visible attributes upon which females could base mate choice showed little correlation with energetic reserves (glycogen levels, condition factor or tissue masses), coloration and carotenoid contents were positively correlated with the levels of several enzymes involved in anaerobic ATP production in skeletal muscle.