Carotenoids in Human Skin In Vivo: Antioxidant and Photo-Protectant Role against External and Internal Stressors

Abstract

The antioxidant system of the human body plays a crucial role in maintaining redox homeostasis and has an important protective function. Carotenoids have pronounced antioxidant properties in the neutralization of free radicals. In human skin, carotenoids have a high concentration in the stratum corneum (SC)—the horny outermost layer of the epidermis, where they accumulate within lipid lamellae. Resonance Raman spectroscopy and diffuse reflectance spectroscopy are optical methods that are used to non-invasively determine the carotenoid concentration in the human SC in vivo. It was shown by electron paramagnetic resonance spectroscopy that carotenoids support the entire antioxidant status of the human SC in vivo by neutralizing free radicals and thus, counteracting the development of oxidative stress. This review is devoted to assembling the kinetics of the carotenoids in the human SC in vivo using non-invasive optical and spectroscopic methods. Factors contributing to the changes of the carotenoid concentration in the human SC and their influence on the antioxidant status of the SC in vivo are summarized. The effect of chemotherapy on the carotenoid concentration of the SC in cancer patients is presented. A potential antioxidant-based pathomechanism of chemotherapy-induced hand-foot syndrome and a method to reduce its frequency and severity are discussed.

Naturally Occurring Functional Ingredient from Filamentous Thermophilic Cyanobacterium Leptolyngbya sp. KC45: Phytochemical Characterizations and Their Multiple Bioactivities

“…KC45 might possibly be employed as a DPPH inhibitor to protect cells from oxidative stress by scavenging DPPH free radicals. It was discovered that chlorophylls [ 6 ], carotenoids [ 101 ], and phenolics [ 5 ] could all play a significant role in the process of scavenging DPPH free radicals. Similarly, the phytochemicals obtained from plants and algae with different solvent extraction methods, such as the methanolic extract of edible macroalgae [ 1 ], the methanol extract of Clausena excavata , Clausena harmandiana , and Murraya koenigii [ 30 ], the methanolic extracts of Leptolyngbya sp.…”

Correlation between Blood Flow and Various Physiological Parameters in Human Skin

“…Carotenoids are fat-soluble molecules with a powerful antioxidant capacity against reactive oxygen species [26][27][28]. Carotenoids are dissolved in the blood plasma [29] and have a beneficial function in the human skin [6]. Carotenoids can be quantified separately using high performance liquid chromatography [9,30] and as a total concentration using photometric absorption at 450 and 525 nm [31] or by Raman spectroscopy [29] directly in blood plasma samples.…”

“…This concerns, but is not limited to the determination of the glucose concentration in blood samples using attenuated total reflection Fouriertransform infrared (ATR-FTIR) spectroscopy [1,2] as well as the analysis of the influence of topically applied substances on the blood flow using laser Doppler flowmetry [3][4][5]. Antioxidants like carotenoids betacarotene and lycopene could be detected in the blood plasma correlating to the antioxidant status of human skin and reflecting health conditions in animals [6]. Noninvasive measurements of carotenoids in the skin are limited to the application of Raman spectroscopy and reflection spectroscopy [7][8][9].…”

“…Noninvasive measurements of carotenoids in the skin are limited to the application of Raman spectroscopy and reflection spectroscopy [7][8][9]. The in vivo investigations of the cutaneous antioxidant status were carried out both on humans and in veterinary medicine on cattle [6,10]. Furthermore, blood capillaries were visualized non-invasively in human skin using two-photon excited fluorescence lifetime imaging [11], which extends the application of confocal laser scanning microscopy and optical coherent tomography in dermatology [12][13][14].…”

Modulation of Membrane Microviscosity by Protein-Mediated Carotenoid Delivery as Revealed by Time-Resolved Fluorescence Anisotropy

“…In particular, carotenoids form the basis for visual pigments responsible for light perception and color discrimination. In humans, carotenoids have been also detected in skin by non-invasive optical techniques [ 4 , 5 ] and in the yellow spot in the macular region of the retina [ 6 ]. Much attention has been attracted to the presence of various carotenoids in neural cells [ 7 ], including the human brain [ 8 ].…”