Submit to IJMS Review for IJMS Propose a Special Issue

Journal Menu

Journal Browser

Bioactive Phenolics and Polyphenols 2020

Special Issue Editors
Special Issue Information
Keywords
Benefits of Publishing in a Special Issue
Related Special Issues
Published Papers

A special issue of International Journal of Molecular Sciences (ISSN 1422-0067). This special issue belongs to the section "Bioactives and Nutraceuticals".

Deadline for manuscript submissions: closed (15 August 2020) | Viewed by 78807

Share This Special Issue

Special Issue Editors

Prof. Dr. Luis Cisneros-Zevallos

E-Mail Website
Guest Editor

Department of Horticultural Sciences, Texas A&M University, College Station, TX 77843-2133, USA
Interests: secondary metabolism of plants under stress conditions; functional foods and cell molecular targets; postharvest biology and technology
Special Issues, Collections and Topics in MDPI journals

Prof. Dr. Daniel Jacobo-Velazquez

E-Mail Website
Guest Editor

Centro de Biotecnología-FEMSA, School of Engineering and Sciences. Tecnológico de Monterrey. E. Garza Sada 2501 Sur, C.P. 64849, Monterrey, N.L., Mexico
Interests: phenolics biosynthesis; methods of analysis; antioxidant activity; non-thermal processing technologies; extraction and purification techniques; postharvest physiology; postharvest stress responses
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

This Special Issue, "Bioactive Phenolics and Polyphenols 2020", which is a continuation of our previous Special Issue "Bioactive Phenolics and Polyphenols 2018" (https://www.mdpi.com/journal/ijms/special_issues/bioactive_phenolics), will cover a selection of recent research topics and current review articles in the field of bioactive phenolics and polyphenols. Experimental papers, up-to-date review articles, and commentaries are all welcome.

The scientific interest in plant phenolics as chemopreventive and therapeutic agents against chronic and degenerative diseases has been increasing since the late 1990s, when the French paradox was associated to the high intake of polyphenols present in red wine. Since then, research advances include their biosynthesis, biological activities, purification, and chemical characterization in different plant species. Furthermore, research on the stability of phenolics in food processing techniques and storage is an area of major interest.

Contributions to this Special Issue, may cover all aspects of phenolics and polyphenols including: not only their chemical characterization on different plant species; methods for their extraction, purification, and quantification; but also elucidation of their mechanism of action; development of innovative methods for the evaluation of their bioactivity in vitro and in vivo; evaluation of their stability to thermal and non-thermal food processing techniques; elicitation of plant phenolic biosynthesis pathway; and effect of postharvest handling on the phenolic profiles of plant foods. Papers regarding the development of food products and dietary supplements enriched with plant phenolics will be also taken into consideration.

Prof. Dr. Luis Cisneros-Zevallos
Prof. Dr. Daniel Jacobo-Velazquez
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. International Journal of Molecular Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. There is an Article Processing Charge (APC) for publication in this open access journal. For details about the APC please see here. Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

Phenolic metabolism
Biological activities
Stability to food processing
Elicitation
Methods of analysis
Dietary supplements
Nutraceutical ingredients
Non-thermal processing
Extraction and purification

Benefits of Publishing in a Special Issue

Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Related Special Issues

Bioactive Phenolics and Polyphenols 2018 in International Journal of Molecular Sciences (27 articles)
Bioactive Phenolics and Polyphenols in International Journal of Molecular Sciences (23 articles)

Published Papers (11 papers)

Download All Papers

Order results

Result details

Show export options Show export options

Select all

Export citation of selected articles as:

Research

Jump to: Review

16 pages, 3248 KiB

Open AccessArticle

Lablab purpureus Protects HaCaT Cells from Oxidative Stress-Induced Cell Death through Nrf2-Mediated Heme Oxygenase-1 Expression via the Activation of p38 and ERK1/2

by Nurud Diniyah, Md Badrul Alam, Hee-Jeong Choi and Sang-Han Lee

Int. J. Mol. Sci. 2020, 21(22), 8583; https://doi.org/10.3390/ijms21228583 - 14 Nov 2020

Cited by 13 | Viewed by 4075

Abstract

Ultraviolet B (UV-B) radiation induces the extreme production of either reactive oxygen species (ROS) or inflammatory mediators. The aim of this study was to evaluate the antioxidant activities of 70% ethanolic extract of Lablab purpureus (LPE) and the underlying mechanisms using HaCaT cells exposed to UV-B. High-performance liquid chromatography (HPLC) confirmed the presence of gallic acid, catechin, and epicatechin in LPE. LPE was shown to have a very potent capacity to scavenge free radicals. The results showed that LPE prevented DNA damage and inhibited the generation of ROS in HaCaT cells without causing any toxicity. LPE increased the expression of endogenous antioxidant enzymes such as superoxide dismutase-1 and catalase. Furthermore, LPE treatment facilitates the nuclear translocation of nuclear factor (erythroid-derived 2)-like 2 (Nrf-2), boosting the phase II detoxifying enzyme heme oxygenase-1 (HO-1) leading to the combatting of oxidative stress. However, pretreatment of LPE also caused the phosphorylation of mitogen-activated protein kinases (MAPK kinase) (p38 kinase) and extracellular signal-regulated kinase (ERK), whereas treatment with p38 and ERK inhibitors substantially suppressed LPE-induced Nrf2 and heme oxygenase (HO)-1 expression. These findings suggest that LPE exhibits antioxidant activity via Nrf-2-mediated HO-1 signaling through the activation of p38 and ERK, indicating that LPE can potentially be used as a remedy to combat oxidative stress-induced disorder. Full article

(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols 2020)

► Show Figures

Figure 1

15 pages, 3233 KiB

Open AccessArticle

Phenolic-Enriched Collagen Fibrillar Coatings on Titanium Alloy to Promote Osteogenic Differentiation and Reduce Inflammation

by Anna Mieszkowska, Harrison Beaumont, Laurine Martocq, Andrey Koptyug, Maria A. Surmeneva, Roman A. Surmenev, Javad Naderi, Timothy E.L. Douglas and Katarzyna A. Gurzawska-Comis

Int. J. Mol. Sci. 2020, 21(17), 6406; https://doi.org/10.3390/ijms21176406 - 3 Sep 2020

Cited by 20 | Viewed by 3354

Abstract

The adsorption of biomolecules on biomaterial surfaces can promote their integration with surrounding tissue without changing their bulk properties. For biomaterials in bone reconstruction, the promotion of osteogenic differentiation and reduction of inflammation are desirable. Fibrillar coatings are interesting because of fibrils’ high surface area-volume ratio, aiding adsorption and adhesion. Fibrils also serve as a matrix for the immobilization of biomolecules with biological activity, such as the phenolic compound phloroglucinol (PG), the subunit of marine polyphenols. The aim of this work was to investigate the influence of PG coatings on fibroblast- and osteoblast-like cells to increase the osseointegration of titanium implants. Collagen fibril coatings, containing PG at low and high concentrations, were produced on titanium alloy (Ti6Al4V) scaffolds generated by additive manufacturing (AM). These coatings, especially PG-enriched coatings, reduced hydrophobicity and modulated the behavior of human osteosarcoma SaOS-2 and mouse embryonic fibroblast 3T3 cell lines. Both osteoblastic and fibroblastic cells spread and adhered well on PG-enriched coatings. Coatings significantly reduced the inflammatory response. Moreover, osteogenic differentiation was promoted by collagen coatings with a high PG concentration. Thus, the enrichment of collagen fibril coatings with PG is a promising strategy to improve Ti6Al4V implants for bone contact in orthopedics and dentistry and is worthy of further investigation. Full article

(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols 2020)

► Show Figures

Figure 1

26 pages, 8070 KiB

Open AccessArticle

Viburnum opulus L. Juice Phenolic Compounds Influence Osteogenic Differentiation in Human Osteosarcoma Saos-2 Cells

by Małgorzata Zakłos-Szyda, Adriana Nowak, Nina Pietrzyk and Anna Podsędek

Int. J. Mol. Sci. 2020, 21(14), 4909; https://doi.org/10.3390/ijms21144909 - 11 Jul 2020

Cited by 21 | Viewed by 4922

Abstract

Bone mass loss occurs with a decrease in osteoblast proliferation and differentiation, or the enhancement of bone resorption, which further leads to the impairment of bone mineral density and increase in bone fracture. Recent studies suggest that some phenolic compounds found in food play positive role in bone metabolism. High content of phenolic compounds with potential beneficial effects on bone metabolism have been identified in the Viburnum opulus fruit. The aim of the study was to determine the influence of V. opulus fresh juice (FJ) and juice purified by solid phase extraction (PJ) on osteogenesis processes with osteosarcoma Saos-2 cell lines. V. opulus purified juice revealed stronger potential as an inducer of Saos-2 osteogenic differentiation. Saos-2 cells matrix mineralization was evaluated with alkaline phosphatase (ALP) activity measurement and alizarin red S staining. Gene expression analysis showed the elevation of the mRNA levels of Runt-related transcription factor 2 (RUNX2), ALP, collagen type 1 and osteonectin, whereas the nuclear factor-κB ligand and osteoprotegerin ratio (RANKL/OPG) decreased. Furthermore, V. opulus was able to diminish the secretion of pro-inflammatory cytokines Il6 and TNFα, however had no effect on vascular endothelial growth factor (VEGF). It decreased intracellular oxidative stress and induced DNA repair, but had no effect on the growth inhibition of lactic acid beneficial microorganisms. Full article

(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols 2020)

► Show Figures

Graphical abstract

17 pages, 1630 KiB

Open AccessArticle

Effects of Apigenin on RBL-2H3, RAW264.7, and HaCaT Cells: Anti-Allergic, Anti-Inflammatory, and Skin-Protective Activities

by Che-Hwon Park, Seon-Young Min, Hye-Won Yu, Kyungmin Kim, Suyeong Kim, Hye-Ja Lee, Ji-Hye Kim and Young-Jin Park

Int. J. Mol. Sci. 2020, 21(13), 4620; https://doi.org/10.3390/ijms21134620 - 29 Jun 2020

Cited by 118 | Viewed by 13529

Abstract

Apigenin (4′,5,7-trihydroxyflavone, flavonoid) is a phenolic compound that is known to reduce the risk of chronic disease owing to its low toxicity. The first study on apigenin analyzed its effect on histamine release in the 1950s. Since then, anti-mutation and antitumor properties of apigenin have been widely reported. In the present study, we evaluated the apigenin-mediated amelioration of skin disease and investigated its applicability as a functional ingredient, especially in cosmetics. The effect of apigenin on RAW264.7 (murine macrophage), RBL-2H3 (rat basophilic leukemia), and HaCaT (human immortalized keratinocyte) cells were analyzed. Apigenin (100 μM) significantly inhibited nitric oxide (NO) production, cytokine expression (interleukin (IL)-1β, IL6, cyclooxygenase (COX)-2, and inducible nitric oxide synthase [iNOS]), and phosphorylation of mitogen-activated protein kinase (MAPK) signal molecules, including extracellular signal-regulated kinase (ERK) and c-Jun N-terminal protein kinase (JNK) in RAW264.7 cells. Apigenin (30 μM) also inhibited the phosphorylation of signaling molecules (Lyn, Syk, phospholipase Cγ1, ERK, and JNK) and the expression of high-affinity IgE receptor FcεRIα and cytokines (tumor necrosis factor (TNF)-α, IL-4, IL-5, IL-6, IL-13, and COX-2) that are known to induce inflammation and allergic responses in RBL-2H3 cells. Further, apigenin (20 μM) significantly induced the expression of filaggrin, loricrin, aquaporin-3, hyaluronic acid, hyaluronic acid synthase (HAS)-1, HAS-2, and HAS-3 in HaCaT cells that are the main components of the physical barrier of the skin. Moreover, it promoted the expression of human β-defensin (HBD)-1, HBD-2, HBD-3, and cathelicidin (LL-37) in HaCaT cells. These antimicrobial peptides are known to play an important role in the skin as chemical barriers. Apigenin significantly suppressed the inflammatory and allergic responses of RAW264.7 and RBL cells, respectively, and would, therefore, serve as a potential prophylactic and therapeutic agent for immune-related diseases. Apigenin could also be used to improve the functions of the physical and chemical skin barriers and to alleviate psoriasis, acne, and atopic dermatitis. Full article

(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols 2020)

► Show Figures

Graphical abstract

20 pages, 1596 KiB

Open AccessArticle

Synergistic Combinations of Curcumin, Sulforaphane, and Dihydrocaffeic Acid against Human Colon Cancer Cells

by Jesús Santana-Gálvez, Javier Villela-Castrejón, Sergio O. Serna-Saldívar, Luis Cisneros-Zevallos and Daniel A. Jacobo-Velázquez

Int. J. Mol. Sci. 2020, 21(9), 3108; https://doi.org/10.3390/ijms21093108 - 28 Apr 2020

Cited by 22 | Viewed by 4601

Abstract

Nutraceutical combinations that act synergistically could be a powerful solution against colon cancer, which is the second deadliest malignancy worldwide. In this study, curcumin (C), sulforaphane (S), and dihydrocaffeic acid (D, a chlorogenic acid metabolite) were evaluated, individually and in different combinations, over the viability of HT-29 and Caco-2 colon cancer cells, and compared against healthy fetal human colon (FHC) cells. The cytotoxic concentrations to kill 50%, 75%, and 90% of the cells (CC₅₀, CC₇₅, and CC₉₀) were obtained, using the MTS assay. Synergistic, additive, and antagonistic effects were determined by using the combination index (CI) method. The 1:1 combination of S and D exerted synergistic effects against HT-29 at 90% cytotoxicity level (doses 90:90 µM), whereas CD(1:4) was synergistic at all cytotoxicity levels (9:36–34:136 µM) and CD(9:2) at 90% (108:24 µM) against Caco-2 cells. SD(1:1) was significantly more cytotoxic for cancer cells than healthy cells, while CD(1:4) and CD(9:2) were similarly or more cytotoxic for healthy cells. Therefore, the SD(1:1) combination was chosen as the best. A model explaining SD(1:1) synergy is proposed. SD(1:1) can be used as a basis to develop advanced food products for the prevention/co-treatment of colon cancer. Full article

(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols 2020)

► Show Figures

Figure 1

17 pages, 2898 KiB

Open AccessArticle

Effect of a Resveratrol/Quercetin Mixture on the Reversion of Hypertension Induced by a Short-Term Exposure to High Sucrose Levels Near Weaning and a Long-Term Exposure That Leads to Metabolic Syndrome in Rats

by Vicente Castrejón-Téllez, Mariana Villegas-Romero, María Esther Rubio-Ruiz, Israel Pérez-Torres, Elizabeth Carreón-Torres, Eulises Díaz-Díaz and Verónica Guarner-Lans

Int. J. Mol. Sci. 2020, 21(6), 2231; https://doi.org/10.3390/ijms21062231 - 23 Mar 2020

Cited by 13 | Viewed by 3124

Abstract

Hypertension is an important global public health problem. Excess sucrose during a short period near weaning (short sucrose period, SSP; sucrose during rat postnatal days 12 to 28) increases the risk of developing hypertension during adulthood and sucrose ingestion for 6 months after weaning also results in metabolic syndrome (MS) accompanied by hypertension. The aim of this study was to test if the mechanisms that lead to hypertension induced by SSP and MS are similarly modified by a resveratrol/quercetin mixture (RSV/QSC) that targets epigenetic cues. We studied the reversion of hypertension by an RSV/QSC mixture administered for 1 month (from month 6 to month 7 of age) in these two models, since it is effective against some signs of MS. RSV/QSC might determine Sirtuin 1 (SIRT1) and Sirtuin 3 (SIRT3) expression that modulates the expression of endothelial nitric oxide synthase (eNOS), which synthesizes nitric oxide (NO), and of superoxide dismutases (SOD1 and 2), which are antioxidant enzymes that have an impact on the NO levels. Short- (SSP) and long-term (MS) exposure to sucrose induced hypertension and RSV/QSC reversed it. It increased the insulin sensitivity, which may determine the eNOS expression. eNOS expression was decreased in aortas from SSP and MS rats and RSV/QSC only elevated its levels in aortas from MS rats. SIRT1 was also only increased in the MS aortas. Hypertension was accompanied by a decrease in total non-enzymatic antioxidant defenses in SSP and MS aortas, which improved with the RSV/QSC treatment. SOD1 expression was not modified by the sucrose treatments, but SOD2 expression was decreased in SSP and MS aortas. The RSV/QSC treatment increased SOD1 expression in MS aortas. SIRT3 was not modified by the sucrose or RSV/QSC treatments. In conclusion, SSP and MS lead to hypertension, but MS leads to more possible epigenetically- regulated mechanisms related to high blood pressure that could be targeted by the RSV/QSC mixture. Therefore, treatment has better effects on hypertension produced by MS. Full article

(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols 2020)

► Show Figures

Graphical abstract

10 pages, 1307 KiB

Open AccessArticle

Structural Requirements of Benzofuran Derivatives Dehydro-δ- and Dehydro-ε-Viniferin for Antimicrobial Activity Against the Foodborne Pathogen Listeria monocytogenes

by Giorgia Catinella, Luce M. Mattio, Loana Musso, Stefania Arioli, Diego Mora, Giovanni Luca Beretta, Nadia Zaffaroni, Andrea Pinto and Sabrina Dallavalle

Int. J. Mol. Sci. 2020, 21(6), 2168; https://doi.org/10.3390/ijms21062168 - 21 Mar 2020

Cited by 15 | Viewed by 2964

Abstract

In a recent study, we investigated the antimicrobial activity of a collection of resveratrol-derived monomers and dimers against a series of foodborne pathogens. Out of the tested molecules, dehydro-δ-viniferin and dehydro-ε-viniferin emerged as the most promising derivatives. To define the structural elements essential to the antimicrobial activity against the foodborne pathogen L. monocytogenes Scott A as a model Gram-positive microorganism, the synthesis of a series of simplified benzofuran-containing derivatives was carried out. The systematic removal of the aromatic moieties of the parent molecules allowed a deeper insight into the most relevant structural features affecting the activity. While the overall structure of compound 1 could not be altered without a substantial loss of antimicrobial activity, the structural simplification of compound 2 (minimal inhibitory concentration (MIC) 16 µg/mL, minimal bactericidal concentration (MBC) >512 µg/mL) led to the analogue 7 with increased activity (MIC 8 µg/mL, MBC 64 µg/mL). Full article

(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols 2020)

► Show Figures

Graphical abstract

Review

Jump to: Research

41 pages, 895 KiB

Open AccessReview

Phenolic Compounds in Mesoamerican Fruits—Characterization, Health Potential and Processing with Innovative Technologies

by Andrea Gómez-Maqueo, Zamantha Escobedo-Avellaneda and Jorge Welti-Chanes

Int. J. Mol. Sci. 2020, 21(21), 8357; https://doi.org/10.3390/ijms21218357 - 7 Nov 2020

Cited by 24 | Viewed by 4884

Abstract

Diets rich in phenolic compounds have been associated to reducing the risk of metabolic syndrome and its derived disorders. Fruits are healthy components of the human diet because of their vitamin, mineral, fiber and phenolic profile. However, they have a short shelf-life which is limited by microbiological growth and enzymatic activity. Innovative preservation methods such as high hydrostatic pressure, pulsed electric fields, ultrasound, microwave, cold plasma and ultraviolet light have become popular for the processing of fruits because they can preserve nutritional quality. In this review, the phenolic profile and health potential of 38 Mesoamerican fruits were assessed. Phenolic compounds were classified based on their contribution to the diet as flavonoids, phenolic acids, tannin, lignins and stilbenoids. Due to this composition, fruits showed a wide range of bioactivities which included anti-inflammatory, anti-diabetic, anti-hypertensive and anti-obesity activities, among others. Phenolic content in fruits submitted to innovative food processing technologies depended on parameters such as enzymatic activity, antioxidant capacity, microstructure integrity and cell viability. Innovative technologies could increase phenolic content while assuring microbiological safety by (i) promoting the release of bound phenolic compounds during processing and (ii) inducing the synthesis of phenolic compounds by activation of phenylpropanoid pathway during storage. Full article

(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols 2020)

► Show Figures

Graphical abstract

24 pages, 2145 KiB

Open AccessReview

Anti-Obesity Effects of Polyphenol Intake: Current Status and Future Possibilities

by Mariarosaria Boccellino and Stefania D’Angelo

Int. J. Mol. Sci. 2020, 21(16), 5642; https://doi.org/10.3390/ijms21165642 - 6 Aug 2020

Cited by 155 | Viewed by 14125

Abstract

The prevalence of obesity has steadily increased worldwide over the past three decades. The conventional approaches to prevent or treat this syndrome and its associated complications include a balanced diet, an increase energy expenditure, and lifestyle modification. Multiple pharmacological and non-pharmacological interventions have been developed with the aim of improving obesity complications. Recently, the use of functional foods and their bioactive components is considered a new approach in the prevention and management of this disease. Due to their biological properties, polyphenols may be considered as nutraceuticals and food supplement recommended for different syndromes. Polyphenols are a class of naturally-occurring phytochemicals, some of which have been shown to modulate physiological and molecular pathways involved in energy metabolism. Polyphenols could act in the stimulation of β-oxidation, adipocyte differentiation inhibition, counteract oxidative stress, etc. In this narrative review, we considered the association between polyphenols (resveratrol, quercetin, curcumin, and some polyphenolic extracts) and obesity, focusing on human trials. The health effects of polyphenols depend on the amount consumed and their bioavailability. Some results are contrasting, probably due to the various study designs and lengths, variation among subjects (age, gender, ethnicity), and chemical forms of the dietary polyphenols used. But, in conclusion, the data so far obtained encourage the setting of new trials, necessary to validate benefic role of polyphenols in obese individuals. Full article

(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols 2020)

► Show Figures

Graphical abstract

27 pages, 2127 KiB

Open AccessReview

A Re-Appraisal of Pathogenic Mechanisms Bridging Wet and Dry Age-Related Macular Degeneration Leads to Reconsider a Role for Phytochemicals

by Roberto Pinelli, Francesca Biagioni, Fiona Limanaqi, Miorica Bertelli, Elena Scaffidi, Maico Polzella, Carla Letizia Busceti and Francesco Fornai

Int. J. Mol. Sci. 2020, 21(15), 5563; https://doi.org/10.3390/ijms21155563 - 3 Aug 2020

Cited by 13 | Viewed by 6213

Abstract

Which pathogenic mechanisms underlie age-related macular degeneration (AMD)? Are they different for dry and wet variants, or do they stem from common metabolic alterations? Where shall we look for altered metabolism? Is it the inner choroid, or is it rather the choroid–retinal border? Again, since cell-clearing pathways are crucial to degrade altered proteins, which metabolic system is likely to be the most implicated, and in which cell type? Here we describe the unique clearing activity of the retinal pigment epithelium (RPE) and the relevant role of its autophagy machinery in removing altered debris, thus centering the RPE in the pathogenesis of AMD. The cell-clearing systems within the RPE may act as a kernel to regulate the redox homeostasis and the traffic of multiple proteins and organelles toward either the choroid border or the outer segments of photoreceptors. This is expected to cope with the polarity of various domains within RPE cells, with each one owning a specific metabolic activity. A defective clearance machinery may trigger unconventional solutions to avoid intracellular substrates’ accumulation through unconventional secretions. These components may be deposited between the RPE and Bruch’s membrane, thus generating the drusen, which remains the classic hallmark of AMD. These deposits may rather represent a witness of an abnormal RPE metabolism than a real pathogenic component. The empowerment of cell clearance, antioxidant, anti-inflammatory, and anti-angiogenic activity of the RPE by specific phytochemicals is here discussed. Full article

(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols 2020)

► Show Figures

Figure 1

83 pages, 29878 KiB

Open AccessReview

An Overview of Coumarin as a Versatile and Readily Accessible Scaffold with Broad-Ranging Biological Activities

by Francesca Annunziata, Cecilia Pinna, Sabrina Dallavalle, Lucia Tamborini and Andrea Pinto

Int. J. Mol. Sci. 2020, 21(13), 4618; https://doi.org/10.3390/ijms21134618 - 29 Jun 2020

Cited by 268 | Viewed by 15727

Abstract

Privileged structures have been widely used as an effective template for the research and discovery of high value chemicals. Coumarin is a simple scaffold widespread in Nature and it can be found in a considerable number of plants as well as in some fungi and bacteria. In the last years, these natural compounds have been gaining an increasing attention from the scientific community for their wide range of biological activities, mainly due to their ability to interact with diverse enzymes and receptors in living organisms. In addition, coumarin nucleus has proved to be easily synthetized and decorated, giving the possibility of designing new coumarin-based compounds and investigating their potential in the treatment of various diseases. The versatility of coumarin scaffold finds applications not only in medicinal chemistry but also in the agrochemical field as well as in the cosmetic and fragrances industry. This review is intended to be a critical overview on coumarins, comprehensive of natural sources, metabolites, biological evaluations and synthetic approaches. Full article

(This article belongs to the Special Issue Bioactive Phenolics and Polyphenols 2020)

► Show Figures

Journal Menu

Journal Browser

Bioactive Phenolics and Polyphenols 2020

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Related Special Issues

Published Papers (11 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI