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Vignesh V, Kavalappa YP, Ponesakki G, Madhan B, Shanmugam G. Lutein, a carotenoid found in numerous plants and the human eye, demonstrates the capacity to bundle collagen fibrils. Int J Biol Macromol 2024; 274:133389. [PMID: 38925203 DOI: 10.1016/j.ijbiomac.2024.133389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 05/29/2024] [Accepted: 06/21/2024] [Indexed: 06/28/2024]
Abstract
Collagen fibrils serve as the building blocks of the extracellular matrix, providing a resilient and structural framework for tissues. However, the bundling of collagen fibrils is of paramount importance in maintaining the structural integrity and functionality of various tissues in the human body. In this scenario, there is limited exploration of molecules that promote the bundling of collagen fibrils. Investigating the interactions of well-known carotenoids, commonly associated with ocular health, particularly in the retina, with collagen presents a novel and significant area of study. Here, we studied the influence of lutein, a well-known carotenoid present in many plant tissues and has several biological properties, on the structure, thermal stability, self-assembly, and fibrillation of collagen. Fibrillation kinetics and electron microscopic analyses indicated that lutein did not interfere with fibrillation process of collagen, whereas it enhances the lateral fusion of collagen fibrils leading to the formation of compact bundles of thick fibrils under physiological conditions. The hydrophobic and hydrogen bonding interactions between lutein and collagen fibrils are most likely the cause of the bundling of the fibrils. This study establishes the first investigation of collagen-carotenoid interactions, showcasing the unique property of lutein in bundling collagen fibrils, which may find potential application in tissue engineering.
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Affiliation(s)
- Venkatesan Vignesh
- Organic & Bioorganic Chemistry Laboratory, Council of Scientific and Industrial Research - Central Leather Research Institute (CSIR-CLRI), Sardar Patel Road, Adyar, Chennai 600020, India
| | - Yogendra Prasad Kavalappa
- Biochemistry and Biotechnology Laboratory, CSIR-CLRI, Sardar Patel Road, Adyar, Chennai 600 020, India
| | - Ganesan Ponesakki
- Biochemistry and Biotechnology Laboratory, CSIR-CLRI, Sardar Patel Road, Adyar, Chennai 600 020, India
| | - Balaraman Madhan
- Biochemistry and Biotechnology Laboratory, CSIR-CLRI, Sardar Patel Road, Adyar, Chennai 600 020, India
| | - Ganesh Shanmugam
- Organic & Bioorganic Chemistry Laboratory, Council of Scientific and Industrial Research - Central Leather Research Institute (CSIR-CLRI), Sardar Patel Road, Adyar, Chennai 600020, India.
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Ahn S, Hwang JE, Kim YJ, Eom K, Jung MH, Moon H, Ham D, Park JM, Oh SU, Park JY, Joung H. Examination of the utility of skin carotenoid status in estimating dietary intakes of carotenoids and fruits and vegetables: A randomized, parallel-group, controlled feeding trial. Nutrition 2024; 119:112304. [PMID: 38154397 DOI: 10.1016/j.nut.2023.112304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 11/01/2023] [Accepted: 11/16/2023] [Indexed: 12/30/2023]
Abstract
OBJECTIVE Optical spectroscopy-measured skin carotenoid status (SCS) has been validated for estimating fruit and vegetable (F&V) intake; however, there is limited research addressing SCS kinetics in whole-diet interventions. The aim of this controlled feeding trial was to explore SCS's response to carotenoid intake changes via whole-diet intervention, evaluating its biomarker potential. METHODS Eighty participants ages 20 to 49 y, without underlying diseases, were randomly allocated to the high-carotenoid group (HG; n = 40) or control group (CG; n = 40). The HG consumed a high-carotenoid diet (21 mg total carotenoids/2000 kcal), whereas the CG consumed a control diet (13.6 mg total carotenoids/2000 kcal) for 6 wk. Subsequently, skin and blood carotenoid concentrations were tracked without intervention for 4 wk. SCS was measured weekly via resonance Raman spectroscopy, and serum carotenoid concentrations were analyzed biweekly using high-performance liquid chromatography. Baseline carotenoid and F&V intakes were assessed via a 3-d diet record. The kinetics of SCS and serum carotenoid concentrations were analyzed using a weighted generalized estimating equation. Pearson's correlation analyses were used to examine baseline correlations between SCS and dietary carotenoid and F&V intakes, as well as serum carotenoid concentrations. RESULTS During the intervention, the HG showed a faster and greater SCS increase than the CG (difference in slope per week = 8.87 AU, Pinteraction <0.001). Baseline SCS had positive correlations with total carotenoid intake (r = 0.45), total F&V intake (r = 0.49), and total serum carotenoid concentration (r = 0.79; P < 0.001 for all). CONCLUSION These results suggest that SCS is a valid biomarker for monitoring changes in carotenoid intake through whole diet, which supports using SCS for assessing carotenoid-rich F&V intake.
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Affiliation(s)
- Seoeun Ahn
- Department of Public Health Science, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea; Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea
| | - Jeong-Eun Hwang
- Department of Public Health Science, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea; Device Research Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon, Gyeonggi-do, Republic of Korea
| | - Yoon Jae Kim
- Device Research Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon, Gyeonggi-do, Republic of Korea
| | - Kunsun Eom
- Device Research Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon, Gyeonggi-do, Republic of Korea
| | - Myoung Hoon Jung
- Device Research Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon, Gyeonggi-do, Republic of Korea
| | - HyunSeok Moon
- Device Research Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon, Gyeonggi-do, Republic of Korea
| | - Dongwoo Ham
- Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea
| | - Ji Min Park
- Department of Public Health Science, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea
| | - Se Uk Oh
- Department of Public Health Science, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea
| | - Jin-Young Park
- Device Research Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon, Gyeonggi-do, Republic of Korea.
| | - Hyojee Joung
- Department of Public Health Science, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea; Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea.
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Montuori E, Lima S, Marchese A, Scargiali F, Lauritano C. Lutein Production and Extraction from Microalgae: Recent Insights and Bioactive Potential. Int J Mol Sci 2024; 25:2892. [PMID: 38474137 DOI: 10.3390/ijms25052892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 02/27/2024] [Accepted: 02/27/2024] [Indexed: 03/14/2024] Open
Abstract
Microalgae have been reported to be excellent producers of bioactive molecules. Lutein is a pigment reported to have various beneficial effects for humans, and especially for eye well-being. In the current review, we summarize various methods that have been developed to optimize its extraction and bioactivities reported for human health. Several protective effects have been reported for lutein, including antioxidant, anticancer, anti-inflammatory, and cardioprotective activity. This review also reports attempts to increase lutein production by microalgae by changing culturing parameters or by using pilot-scale systems. Genetic engineering lutein production is also discussed. Considering the increasing aging of the worldwide population will create an increased need for lutein, a viable economic and eco-sustainable method to produce lutein is needed to face this market demand.
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Affiliation(s)
- Eleonora Montuori
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale F. Stagno d'Alcontres 31, 98166 Messina, Italy
- Department of Ecosustainable Marine Biotechnology, Stazione Zoologica Anton Dohrn, Via Acton 55, 80133 Napoli, Italy
| | - Serena Lima
- Department of Engineering, University of Palermo, Viale delle Scienze ed. 6, 90128 Palermo, Italy
| | - Arima Marchese
- Department of Engineering, University of Palermo, Viale delle Scienze ed. 6, 90128 Palermo, Italy
| | - Francesca Scargiali
- Department of Engineering, University of Palermo, Viale delle Scienze ed. 6, 90128 Palermo, Italy
| | - Chiara Lauritano
- Department of Ecosustainable Marine Biotechnology, Stazione Zoologica Anton Dohrn, Via Acton 55, 80133 Napoli, Italy
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Kitao M, Yamaguchi A, Tomioka T, Kai K, Kamei Y, Sugimoto K, Akagawa M. Astaxanthin protects human ARPE-19 retinal pigment epithelium cells from blue light-induced phototoxicity by scavenging singlet oxygen. Free Radic Res 2023; 57:430-443. [PMID: 37897411 DOI: 10.1080/10715762.2023.2277144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 10/19/2023] [Indexed: 10/30/2023]
Abstract
Age-related macular degeneration (AMD) is one of an increasing number of diseases that causes irreversible impairment and loss of vision in the elderly. AMD occurs by oxidative stress-mediated apoptosis of retinal pigment epithelium cells. The onset of AMD may be positively correlated with the exposure to blue light. We screened food-derived carotenoids for cytoprotective action against blue light irradiation using human ARPE-19 retinal pigment epithelium cells. This study revealed that blue light irradiation triggered apoptosis and oxidative stress in all-trans-retinal (atRAL)-exposed ARPE-19 cells by generating singlet oxygen (1O2), leading to significant cell death. We found that astaxanthin, a potent anti-oxidative xanthophyll abundant in several marine organisms including microalgae, salmon, and shrimp, significantly suppresses blue light-induced apoptotic cell death of atRAL-exposed ARPE-19 cells by scavenging 1O2. Mechanistic studies using the blue-light irradiated cells also demonstrated that the cytoprotective effects of astaxanthin can be attributed to scavenging of 1O2 directly. Our results suggest the potential value of astaxanthin as a dietary strategy to prevent blue light-induced retinal degeneration including AMD.
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Affiliation(s)
- Mana Kitao
- Faculty of Biomolecular Chemistry, Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Ai Yamaguchi
- Faculty of Integrated Bioscience, Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Takuma Tomioka
- Faculty of Biomolecular Chemistry, Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Kenji Kai
- Faculty of Biomolecular Chemistry, Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Yuki Kamei
- Department of Food and Nutrition, Institute of Biomedical sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Kenji Sugimoto
- Faculty of Integrated Bioscience, Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Mitsugu Akagawa
- Department of Food and Nutrition, Institute of Biomedical sciences, Tokushima University Graduate School, Tokushima, Japan
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Md Jaffri J. Reactive Oxygen Species and Antioxidant System in Selected Skin Disorders. Malays J Med Sci 2023; 30:7-20. [PMID: 36875194 PMCID: PMC9984103 DOI: 10.21315/mjms2023.30.1.2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/07/2021] [Indexed: 03/06/2023] Open
Abstract
The skin has a solid protective system that includes the stratum corneum as the primary barrier and a complete antioxidant defence system to maintain the skin's normal redox homeostasis. The epidermal and dermal cells are continuously exposed to physiological levels of reactive oxygen species (ROS) originating from cellular metabolic activities. Environmental insults, such as ultraviolet (UV) rays and air pollutants, also generate ROS that can contribute to structural damage of the skin. The antioxidant defence system ensures that the ROS level remains within the safe limit. In certain skin disorders, oxidative stress plays an important role, and there is an established interplay between oxidative stress and inflammation in the development of the condition. Lower levels of skin antioxidants indicate that oxidative stress may mediate the pathogenesis of the disorder. Accordingly, the total antioxidant level was also found to be lower in individuals with skin disorders in individuals with normal skin conditions. This review attempts to summarise the skin oxidant sources and antioxidant system. In addition, both skin and total antioxidant status of individuals with psoriasis, acne vulgaris, vitiligo and atopic dermatitis (AD), as well as their associations with the progression of these disorders will be reviewed.
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Affiliation(s)
- Juliana Md Jaffri
- Kulliyyah of Pharmacy, International Islamic University Malaysia, Pahang, Malaysia
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Thakur M, Modi VK. Biocolorants in food: Sources, extraction, applications and future prospects. Crit Rev Food Sci Nutr 2022; 64:4674-4713. [PMID: 36503345 DOI: 10.1080/10408398.2022.2144997] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Color of a food is one of the major factors influencing its acceptance by consumers. At presently synthetic dyes are the most commonly used food colorant in food industry by providing more esthetically appearance and as a means to quality control. However, the growing concern about health and environmental due to associated toxicity with synthetic food colorants has accelerated the global efforts to replace them with safer and healthy food colorants obtained from natural resources (plants, microorganisms, and animals). Further, many of these biocolorants not only provide myriad of colors to the food but also exert biological properties, thus they can be used as nutraceuticals in foods and beverages. In order to understand the importance of nature-derived pigments as food colorants, this review provides a thorough discussion on the natural origin of food colorants. Following this, different extraction methods for isolating biocolorants from plants and microbes were also discussed. Many of these biocolorants not only provide color, but also have many health promoting properties, for this reason their physicochemical and biological properties were also reviewed. Finally, current trends on the use of biocolorants in foods, and the challenges faced by the biocolorants in their effective utilization by food industry and possible solutions to these challenges were discussed.
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Affiliation(s)
- Monika Thakur
- Amity Institute of Food Technology, Amity University, Noida, Uttar Pradesh, India
| | - V K Modi
- Amity Institute of Food Technology, Amity University, Noida, Uttar Pradesh, India
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Yamane Y, Mochiji M, Ichioka S, Takayanagi Y, Ishida A, Obana A, Tanito M. Effects of water chestnut ( Tarpa bispinosa Roxb.) extract/lutein on fingertip-measured advanced glycation endproduct/carotenoid levels. Free Radic Res 2022; 56:282-289. [PMID: 35687659 DOI: 10.1080/10715762.2022.2085098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
This pilot study tested the effects of the supplements containing water chestnut extract and carotenoids on antiglycation and carotenoid levels. Twenty Japanese subjects (mean age, 67 ± 7 years; 13 men) ingested 200 mg of Tarpa bispinosa Roxb. extract (containing >50 mg of polyphenols), 20 mg of lutein, and 3 mg of zeaxanthin daily for 3 months. Advanced glycation end product (AGEs) levels were estimated by fingertip skin autofluorescence using the AGEs Sensor; carotenoid levels were estimated by pressure-mediated reflection spectroscopy of the fingertips using the Veggie Meter. Compared to baseline, the mean AGEs score decreased significantly (0.55 ± 0.04 arbitrary units (AU) vs. 0.52 ± 0.07 AU, p = 0.03); the mean carotenoid score increased significantly (256 ± 68 optical density (OD) vs. 302 ± 109 OD, p = 0.02) at 3 months. Blood pressure, body weight, visual acuity, refractive error, and intraocular pressure were equivalent between baseline and 3 months. Compared to baseline, 13 (65%) patients had decreased AGEs scores, and 14 (70%) had increased carotenoid scores at 3 months; 9 (45%) subjects had both decreased AGEs scores and increased carotenoid scores, and two (10%) subjects had an inverse response. Co-administration of water chestnut extract and lutein for 3 months decreased the AGEs and increased the carotenoids estimated in the fingertip skin of humans.
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Affiliation(s)
- Yukari Yamane
- Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo, Japan
| | - Mihoko Mochiji
- Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo, Japan
| | - Sho Ichioka
- Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo, Japan
| | - Yuji Takayanagi
- Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo, Japan
| | - Akiko Ishida
- Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo, Japan
| | - Akira Obana
- Department of Ophthalmology, Seirei Hamamatsu General Hospital, Hamamatsu, Japan
| | - Masaki Tanito
- Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo, Japan
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Kadoh Y, Takayanagi Y, Sasaki J, Tanito M. Fingertip-Measured Skin Carotenoids and Advanced Glycation End Product Levels in Glaucoma. Antioxidants (Basel) 2022; 11:antiox11061138. [PMID: 35740035 PMCID: PMC9220224 DOI: 10.3390/antiox11061138] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 05/30/2022] [Accepted: 06/08/2022] [Indexed: 02/07/2023] Open
Abstract
Carotenoids have antioxidant properties, and the accumulation of advanced glycation end products (AGEs) is associated with reactive oxygen species production; they have attracted attention as factors predictive of the onset and progression in glaucoma. Fingertip measurement is applicable for carotenoids and AGEs due to its noninvasiveness and simplicity. The study included 663 eyes of 663 Japanese subjects (357 males, 306 females). The mean age was 69.9 years with a standard deviation of 11.0. The study population comprised participants with primary open-angle glaucoma (PG) (n = 358), exfoliation glaucoma (EG) (n = 168), and controls (n = 137). Multivariate models suggested that lower skin carotenoid (SC) levels were associated with male gender (standard β = −0.14), AGE scores (−0.24), and a history of intraocular surgery (−0.22). Higher SC levels were associated with higher vegetable intake scores (0.21 for score 3) and diabetes (0.10). However, no association was seen between SCs and glaucoma type. AGEs levels were negatively associated with carotenoid scores (−0.25), PG (−0.15), and smoking habits (−0.26) and positively correlated with EG (0.14). SCs and AGEs were negatively correlated in the single regression analysis (r = −0.20, p < 0.0001). In conclusion, higher levels of AGEs may be candidates for systemic biomarkers of glaucoma associated with the exfoliation syndrome. SC levels can reflect self-reported daily vegetable intake.
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Lutein and Zeaxanthin Intake during Pregnancy and Visual Function in Offspring at 11–12 Years of Age. Nutrients 2022; 14:nu14040872. [PMID: 35215522 PMCID: PMC8876686 DOI: 10.3390/nu14040872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 02/03/2022] [Accepted: 02/16/2022] [Indexed: 02/01/2023] Open
Abstract
(1) Background: Lutein and zeaxanthin (L&Z) are essential dietary nutrients that are a crucial component of the human macula, contributing to visual functioning. They easily cross the placental barrier, so that retinal deposition commences during foetal development. This study aims to assess associations between maternal L&Z intake during pregnancy and offspring visual function at 11–12 years. (2) Methods: Using the Spanish INfancia y Medio Ambiente project (INMA) Sabadell birth cohort, 431 mother–child pairs were analysed. L&Z data were obtained from food frequency questionnaires (FFQ) at week 12 and 32 of pregnancy, alongside other nutritional and sociodemographic covariates. Contrast vision (CS) and visual acuity (VA) were assessed using the automated Freiburg Acuity and Contrast Testing (FRACT) battery. Low CS and VA were defined as being below the 20th cohort centile. Associations were explored using multiple logistic regression. (3) Results: After controlling for potential confounders, L&Z intake during the 1st and 3rd trimester did not reveal any statistically significant association with either CS or VA in offspring at age 11/12 years. (4) Conclusions: No evidence of a long-term association between L&Z intake during pregnancy and visual function in offspring was found. Further larger long-term studies including blood L&Z levels are required to confirm this result.
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Comparative Efficiency of Lutein and Astaxanthin in the Protection of Human Corneal Epithelial Cells In Vitro from Blue-Violet Light Photo-Oxidative Damage. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12031268] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The aim of this study was to compare in vitro the protective and antioxidant properties of lutein and astaxanthin on human primary corneal epithelial cells (HCE-F). To this purpose, HCE-F cells were irradiated with a blue-violet light lamp (415–420 nm) at different energies (20 to 80 J/cm2). Lutein and astaxanthin (50 to 250 μM) were added to HCE-F right before blue-violet light irradiation at 50 J/cm2. Viability was evaluated by the CKK-8 assay while the production of reactive oxygen species (ROS) by the H2DCF-DA assay. Results have shown that the viability of HCE-F cells decreased at light energies from 20 J/cm2 to 80 J/cm2, while ROS production increased at 50 and 80 J/cm2. The presence of lutein or astaxanthin protected the cells from phototoxicity, with lutein slightly more efficient than astaxanthin also on the blunting of ROS, prevention of apoptotic cell death and modulation of the Nrf-2 pathway. The association of lutein and astaxanthin did not give a significant advantage over the use of lutein alone. Taken together, these results suggest that the association of lutein and astaxanthin might be useful to protect cells of the ocular surface from short (lutein) and longer (astaxanthin) wavelengths, as these are the most damaging radiations hitting the eye from many different LED screens and solar light.
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Goji Berry Intake Increases Macular Pigment Optical Density in Healthy Adults: A Randomized Pilot Trial. Nutrients 2021; 13:nu13124409. [PMID: 34959963 PMCID: PMC8708314 DOI: 10.3390/nu13124409] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/10/2021] [Accepted: 12/07/2021] [Indexed: 12/28/2022] Open
Abstract
Age-related macular degeneration (AMD) is the third leading cause of blindness worldwide. Macular pigment optical density (MPOD), a biomarker for AMD, is a non-invasive measure to assess risk. The macula xanthophyll pigments lutein (L) and zeaxanthin (Z) protect against blue light and provide oxidant defense, which can be indexed by MPOD. This study examined the effects of Z-rich goji berry intake on MPOD and skin carotenoids in healthy individuals. A randomized, unmasked, parallel-arm study was conducted with 27 participants, aged 45–65, who consumed either 28 g of goji berries or a supplement containing 6 mg L and 4 mg Z (LZ), five times weekly for 90 days. After 90 days, MPOD was significantly increased in the goji berry group at 0.25 and 1.75 retinal eccentricities (p = 0.029 and p = 0.044, respectively), while no changes were noted in the LZ group. Skin carotenoids were significantly increased in the goji berry group at day 45 (p = 0.025) and day 90 (p = 0.006), but not in the LZ group. Regular intake of goji berries in a healthy middle-aged population increases MPOD may help prevent or delay the development of AMD.
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Lutein and Zeaxanthin Distribution in the Healthy Macula and Its Association with Various Demographic Factors Examined in Pseudophakic Eyes. Antioxidants (Basel) 2021; 10:antiox10121857. [PMID: 34942960 PMCID: PMC8698861 DOI: 10.3390/antiox10121857] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/18/2021] [Accepted: 11/19/2021] [Indexed: 02/06/2023] Open
Abstract
The macular pigment consisting of lutein (L) and zeaxanthin (Z) protects photoreceptors via its antioxidative and barrier activities. This study aimed to determine L and Z distribution in the healthy macula and their association with various demographic factors. Macular pigment optical density (MPOD) was measured using fundus autofluorescence spectroscopy in 352 pseudophakic eyes with no fundus diseases. Pseudophakia was chosen to avoid the influence of cataract in the measurement of fundus autofluorescence. The mean patient age was 72.3 ± 8.6 years. MPOD was analyzed separately in three zones, i.e., A: a central area within a radius of 0.5°, mainly containing Z; B: a ring area with radii from 0.5° to 1.3°, containing Z and L; C: a ring area with radii from 1.3° to 9°, containing L. Multivariate analyses were performed with MPOD as the dependent variable and sex, supplement intake, smoking habits, glaucoma, diabetes, age, body mass index (BMI), skin carotenoid levels, retinal thickness, retinal volume, axial length as the independent variables. The mean total MPOD volume within 9° eccentricity was 20,121 ± 6293. Age was positively associated with MPOD in all zones. Supplement and BMI were positively and negatively associated with MPOD in zones B and C. Smoking was negatively associated with MPOD in zone A. This study revealed the standard MP values of aged Japanese, which resulted to be higher than the previously reported values in other races. Age was found to have a positive association with MP values. L in the outer foveola was affected by BMI and supplements, but Z in the foveola was not. The amount of Z in the Müller cell cone may not be changed easily by factors such as hunger and satiety in the context of preservation of homeostasis in the human body, but tobacco had a negative effect on Z.
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Development of Lutein-Containing Eye Drops for the Treatment of Dry Eye Syndrome. Pharmaceutics 2021; 13:pharmaceutics13111801. [PMID: 34834216 PMCID: PMC8621052 DOI: 10.3390/pharmaceutics13111801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 10/06/2021] [Accepted: 10/22/2021] [Indexed: 11/17/2022] Open
Abstract
Dry eye syndrome (DES) is a common ophthalmological disease that decreases tear secretion and causes dryness, photophobia, pain, severe corneal rupture, and even blindness. Ocular and lacrimal gland inflammation is one of the pathological mechanisms underlying DES. Therefore, effective suppression of inflammation is a crucial strategy for the treatment of DES. Lutein, commonly found in healthy foods, has anti-inflammatory effects in corneal or retina-related cells and may be a potential therapy for DES. The addition of lutein to artificial tears (AT) as an eye-drop formulation for DES treatment in a mouse model was studied in the present work. Polyvinyl alcohol (PVA) was used as a thickener to increase the viscosity of eye drops to prolong drug retention on the ocular surface. A WST-8 assay in human corneal epithelial cells (HCE-2) showed that a concentration of <5 μM lutein (L5) and <1% PVA (P1) maintained the cell viability at 80%. A real-time PCR showed that the inflamed human corneal epithelial cells (HCECs) cocultured with L5P1 had downregulated expression of inflammatory genes such as IL-1β, IL-6, and TNF-α. In a benzalkonium chloride- (BAC) induced DES mouse model, AT/L5P1 could repair damaged corneas, elevate tear secretion, increase the number of goblet cells, and inhibit the production of inflammatory cytokines, such as IL-1β, IL-6, and TNF-α, in the cornea. In conclusion, we demonstrate that lutein/PVA as eye drops could prolong the drug ocular retention time and effectively to decrease inflammation in DES mice. Therefore, lutein, obtained from eye drops, has a potential therapeutic role for DES.
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Watson A, Rostaher A, Fischer NM, Favrot C. A novel therapeutic diet can significantly reduce the medication score and pruritus of dogs with atopic dermatitis during a nine month controlled study. Vet Dermatol 2021; 33:55-e18. [PMID: 34545649 PMCID: PMC9292154 DOI: 10.1111/vde.13020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/29/2021] [Indexed: 11/29/2022]
Abstract
Background Canine atopic dermatitis (cAD) is a common chronic relapsing pruritic skin disease for which management commonly relies on life‐long use of immunomodulatory drugs. A number of the medications used are associated with adverse effects and the potential for complications during long‐term use. Hypothesis The goal of the study was to determine if a complete and balanced diet formulated for therapeutic benefit could contribute towards management of cAD. We hypothesised that the diet would reduce pruritus while also reducing the requirement for medication during the study period. Animals, materials and methods Forty privately owned dogs, having undergone a comprehensive diagnosis for cAD, were randomly allocated to two groups, each group being fed one of two diets (test or control) for up to nine months. We assessed pruritus, Canine Atopic Dermatitis Extent and Severity Index‐(4th iteration) and medication score, the latter reflecting the medication required to maintain a satisfactory quality of life for the animal. Results Both diets were well‐accepted and ‐tolerated. There was a significant improvement in the pruritus score after three months of feeding the therapeutic diet (P = 0.0001). No such improvement was observed at any time point in the group of dogs given the control diet. There was a reduced drug requirement for dogs receiving the therapeutic diet after three months (P = 0.058), and that decrease was significant at six months (P = 0.021) and nine months (P = 0.018). No improvement was seen at any time point in the control group. Conclusion The results suggest that a novel therapeutic diet can assist in the management of cAD by helping to control pruritus and reducing reliance on medication.
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Affiliation(s)
| | - Ana Rostaher
- Clinic for Small Animal Internal Medicine, Vetsuisse Faculty University of Zurich, Winterthurerstrasse 260, Zurich, 8057, Switzerland
| | - Nina M Fischer
- Clinic for Small Animal Internal Medicine, Vetsuisse Faculty University of Zurich, Winterthurerstrasse 260, Zurich, 8057, Switzerland
| | - Claude Favrot
- Clinic for Small Animal Internal Medicine, Vetsuisse Faculty University of Zurich, Winterthurerstrasse 260, Zurich, 8057, Switzerland
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16
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Radtke MD, Poe M, Stookey J, Jilcott Pitts S, Moran NE, Landry MJ, Rubin LP, Stage VC, Scherr RE. Recommendations for the Use of the Veggie Meter® for Spectroscopy-Based Skin Carotenoid Measurements in the Research Setting. Curr Dev Nutr 2021; 5:nzab104. [PMID: 34476333 PMCID: PMC8405124 DOI: 10.1093/cdn/nzab104] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/18/2021] [Accepted: 07/22/2021] [Indexed: 12/20/2022] Open
Abstract
Carotenoids are a class of phytochemical compounds found in a variety of fruits and vegetables (F/V) and, therefore, are commonly used as a biomarker for F/V intake. The Veggie Meter® is a noninvasive research-grade instrument that detects and quantifies carotenoids in the skin. To determine current practices and examine variability among users, a survey was administered to researchers using the device (n = 19, response rate = 35.8%) and variation in anatomical site preparation, calibration, number of measurements, measurement site, and documentation was observed. A protocol was developed in partnership with Veggie Meter® users to outline the preparation, calibration, and data collection procedures for using this device for research purposes. Although many protocol conditions will benefit from additional validation, this standardized protocol supports the development of a universal data repository to establish usual observed ranges, with the ultimate goal of examining associations between skin carotenoid scores and diet-related health outcomes.
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Affiliation(s)
- Marcela D Radtke
- Department of Nutrition, University of California, Davis, Davis, CA, USA
- Center for Nutrition in Schools, University of California, Davis, Davis, CA, USA
| | - Mykaela Poe
- Department of Public Health Sciences, University of California, Davis, Davis, CA, USA
| | - Jodi Stookey
- San Francisco Department of Public Health, San Francisco, CA, USA
| | - Stephanie Jilcott Pitts
- Department of Public Health, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Nancy E Moran
- USDA/Agricultural Research Service Children's Nutrition Research Center and Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Matthew J Landry
- Stanford Prevention Research Center, School of Medicine, Stanford University, Stanford, CA, USA
| | - Lewis P Rubin
- Department of Pediatrics, Georgetown University Medical Center, Washington, DC, USA
| | - Virginia C Stage
- Department of Nutrition Science, East Carolina University, Greenville, NC, USA
| | - Rachel E Scherr
- Department of Nutrition, University of California, Davis, Davis, CA, USA
- Center for Nutrition in Schools, University of California, Davis, Davis, CA, USA
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17
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Di Noia J, Gellermann W. Use of the Spectroscopy-Based Veggie Meter ® to Objectively Assess Fruit and Vegetable Intake in Low-Income Adults. Nutrients 2021; 13:2270. [PMID: 34209048 PMCID: PMC8308249 DOI: 10.3390/nu13072270] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 06/21/2021] [Accepted: 06/29/2021] [Indexed: 12/20/2022] Open
Abstract
Reflection spectroscopy is an emerging approach for noninvasively assessing dermal carotenoids as a biomarker of fruit and vegetable (FV) intake. This study sought to profile and identify determinants of scores from a reflection spectroscopy device (the Veggie Meter (VM)®) among 297 urban, primarily Hispanic low-income adults served by the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). The repeatability of the scores and bi- and multivariate relationships between VM scores, self-reported FV intake measured by a brief screener, and participant characteristics were examined. The mean VM score was 270 (range 0-695); 3- and 6-month test-retest correlations were positive and strong (r = 0.79 and 0.55, respectively). VM scores were negatively associated with body mass index (BMI; r = -0.22) and were higher among participants of Ecuadorian, Dominican, and Mexican Hispanic origin relative to those of Puerto Rican origin; foreign- vs. US-born participants, breastfeeding vs. non-breastfeeding participants, nonsmokers vs. smokers, and participants who consumed three or more cups of FV/day relative to those who consumed less than three cups of FV/day. Foreign-born nativity, consumption of three or more cups of FV/day, and smaller body size were determinants of increased VM scores. Although replication studies are needed to confirm these findings, investigators working with similar populations are encouraged to use the VM to longitudinally track FV intake and to target determinants of the scores in observational and intervention studies of FV intake as measured by the VM.
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Affiliation(s)
- Jennifer Di Noia
- Department of Sociology, William Paterson University, Wayne, NJ 07470, USA
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18
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Wilson LM, Tharmarajah S, Jia Y, Semba RD, Schaumberg DA, Robinson KA. The Effect of Lutein/Zeaxanthin Intake on Human Macular Pigment Optical Density: A Systematic Review and Meta-Analysis. Adv Nutr 2021; 12:2244-2254. [PMID: 34157098 PMCID: PMC8634499 DOI: 10.1093/advances/nmab071] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/15/2021] [Accepted: 05/11/2021] [Indexed: 01/05/2023] Open
Abstract
Lutein, zeaxanthin, and meso-zeaxanthin are the only carotenoids found in the human macula and may have a role in visual function. These carotenoids are reported to protect the retina, and thus vision, as antioxidants and by acting as a blue light filter. Our objective was to determine a minimum concentration of lutein/zeaxanthin intake that is associated with a statistically significant and/or clinically important change in macular pigment optical density (MPOD) among adults with healthy eyes. We searched Ovid MEDLINE, CENTRAL, and the Commonwealth of Agriculture Bureau for English-language studies through to July 2020. Two reviewers screened results to identify studies that evaluated supplements or dietary sources of lutein/zeaxanthin on MPOD among adults with healthy eyes. One reviewer extracted data and assessed strength of evidence, which was confirmed by a second reviewer. Two independent reviewers assessed the risk of bias. Meta-analyses were stratified by total lutein/zeaxanthin dose. We included 46 studies (N = 3189 participants; mean age = 43 y; 42% male). There was no statistically significant change in MPOD among studies evaluating <5 mg/d of total lutein/zeaxanthin intake which primarily assessed dietary interventions for 3-6 mo (pooled mean difference, 0.02; 95% CI: -0.01 to 0.05). The pooled mean increase in MPOD was 0.04 units (95% CI: 0.02 to 0.07) among studies evaluating 5 to <20 mg/d of lutein/zeaxanthin and was 0.11 units (95% CI: 0.06 to 0.16) among studies evaluating ≥20 mg/d of lutein/zeaxanthin for 3-12 mo. MPOD increased with lutein/zeaxanthin intake, particularly at higher doses, among adults with healthy eyes. The effects of lutein/zeaxanthin intake at doses <5 mg/d or from dietary sources is less clear. Increased lutein/zeaxanthin intake can help with maintaining ocular health. Future research is needed to determine the minimum dose and duration of lutein/zeaxanthin intake that is associated with a clinically important change in MPOD or visual function.
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Affiliation(s)
| | - Saraniya Tharmarajah
- Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Yuanxi Jia
- Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Richard D Semba
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA,Center for Human Nutrition, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Debra A Schaumberg
- Department of Ophthalmology & Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, USA,Evidera, Inc., Bethesda, MD, USA
| | - Karen A Robinson
- Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA,Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
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19
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Fleckenstein M, Keenan TDL, Guymer RH, Chakravarthy U, Schmitz-Valckenberg S, Klaver CC, Wong WT, Chew EY. Age-related macular degeneration. Nat Rev Dis Primers 2021; 7:31. [PMID: 33958600 DOI: 10.1038/s41572-021-00265-2] [Citation(s) in RCA: 376] [Impact Index Per Article: 125.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/23/2021] [Indexed: 02/07/2023]
Abstract
Age-related macular degeneration (AMD) is the leading cause of legal blindness in the industrialized world. AMD is characterized by accumulation of extracellular deposits, namely drusen, along with progressive degeneration of photoreceptors and adjacent tissues. AMD is a multifactorial disease encompassing a complex interplay between ageing, environmental risk factors and genetic susceptibility. Chronic inflammation, lipid deposition, oxidative stress and impaired extracellular matrix maintenance are strongly implicated in AMD pathogenesis. However, the exact interactions of pathophysiological events that culminate in drusen formation and the associated degeneration processes remain to be elucidated. Despite tremendous advances in clinical care and in unravelling pathophysiological mechanisms, the unmet medical need related to AMD remains substantial. Although there have been major breakthroughs in the treatment of exudative AMD, no efficacious treatment is yet available to prevent progressive irreversible photoreceptor degeneration, which leads to central vision loss. Compelling progress in high-resolution retinal imaging has enabled refined phenotyping of AMD in vivo. These insights, in combination with clinicopathological and genetic correlations, have underscored the heterogeneity of AMD. Hence, our current understanding promotes the view that AMD represents a disease spectrum comprising distinct phenotypes with different mechanisms of pathogenesis. Hence, tailoring therapeutics to specific phenotypes and stages may, in the future, be the key to preventing irreversible vision loss.
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Affiliation(s)
- Monika Fleckenstein
- Department of Ophthalmology and Visual Science, John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA.
| | - Tiarnán D L Keenan
- Division of Epidemiology and Clinical Applications, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Robyn H Guymer
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Melbourne, VIC, Australia.,Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, VIC, Australia
| | - Usha Chakravarthy
- Department of Ophthalmology, Centre for Public Health, Queen's University of Belfast, Belfast, UK
| | - Steffen Schmitz-Valckenberg
- Department of Ophthalmology and Visual Science, John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA.,Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Caroline C Klaver
- Department of Ophthalmology, Erasmus MC, Rotterdam, Netherlands.,Department of Epidemiology, Erasmus MC, Rotterdam, Netherlands.,Department of Ophthalmology, Radboud Medical Center, Nijmegen, Netherlands.,Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Wai T Wong
- Section on Neuron-Glia Interactions in Retinal Disease, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Emily Y Chew
- Division of Epidemiology and Clinical Applications, National Eye Institute, National Institutes of Health, Bethesda, MD, USA.
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20
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Baswan SM, Klosner AE, Weir C, Salter-Venzon D, Gellenbeck KW, Leverett J, Krutmann J. Role of ingestible carotenoids in skin protection: A review of clinical evidence. PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2021; 37:490-504. [PMID: 33955073 DOI: 10.1111/phpp.12690] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 03/05/2021] [Accepted: 05/03/2021] [Indexed: 12/01/2022]
Abstract
Carotenoids, a class of phytonutrients, have been well established to boost skin's innate resistance against ultraviolet (UV) B-induced erythema (sunburn). Many of the published clinical studies thus far have focused on the measurement of erythema as the primary clinical indicator of skin protection against UVB radiation. More recent studies have shown that carotenoid supplementation provides even more skin protection than previously shown as new clinical and molecular endpoints beyond UVB-induced erythema have been reported. These recent studies have demonstrated that carotenoids also provide photoprotection against UVA-induced pigmentation and inhibit molecular markers of oxidative stress such as intercellular adhesion molecule 1, heme oxygenase-1, and matrix metalloproteinases 1 and 9. This article provides a comprehensive review of the published clinical evidence on skin benefits of carotenoids in the last five decades and indicates new perspectives on the role of ingestible carotenoids in skin protection.
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Affiliation(s)
| | - Allison E Klosner
- Nutrilite Health Institute, Innovation and Science, Amway Corporation, Buena Park, CA, USA
| | - Cathy Weir
- Innovation and Science, Amway Corporation, Ada, MI, USA
| | - Dawna Salter-Venzon
- Nutrilite Health Institute, Innovation and Science, Amway Corporation, Buena Park, CA, USA
| | - Kevin W Gellenbeck
- Nutrilite Health Institute, Innovation and Science, Amway Corporation, Buena Park, CA, USA
| | | | - Jean Krutmann
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany.,Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
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21
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The Effect of Antioxidants on Photoreactivity and Phototoxic Potential of RPE Melanolipofuscin Granules from Human Donors of Different Age. Antioxidants (Basel) 2020; 9:antiox9111044. [PMID: 33114498 PMCID: PMC7693403 DOI: 10.3390/antiox9111044] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 10/16/2020] [Accepted: 10/19/2020] [Indexed: 11/17/2022] Open
Abstract
One of the most prominent age-related changes of retinal pigment epithelium (RPE) is the accumulation of melanolipofuscin granules, which could contribute to oxidative stress in the retina. The purpose of this study was to determine the ability of melanolipofuscin granules from younger and older donors to photogenerate reactive oxygen species, and to examine if natural antioxidants could modify the phototoxic potential of this age pigment. Electron paramagnetic resonance (EPR) oximetry, EPR-spin trapping, and time-resolved detection of near-infrared phosphorescence were employed for measuring photogeneration of superoxide anion and singlet oxygen by melanolipofuscin isolated from younger and older human donors. Phototoxicity mediated by internalized melanolipofuscin granules with and without supplementation with zeaxanthin and α-tocopherol was analyzed in ARPE-19 cells by determining cell survival, oxidation of cellular proteins, organization of the cell cytoskeleton, and the cell specific phagocytic activity. Supplementation with antioxidants reduced aerobic photoreactivity and phototoxicity of melanolipofuscin granules. The effect was particularly noticeable for melanolipofuscin mediated inhibition of the cell phagocytic activity. Antioxidants decreased the extent of melanolipofuscin-dependent oxidation of cellular proteins and disruption of the cell cytoskeleton. Although melanolipofuscin might be involved in chronic phototoxicity of the aging RPE, natural antioxidants could partially ameliorate these harmful effects.
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