Astaxanthin induces migration in human skin keratinocytes via Rac1 activation and RhoA inhibition

Optimization and multiple in vitro activity potentials of carotenoids from marine Kocuria sp. RAM1

Marine pigmented bacteria are a promising natural source of carotenoids. Kocuria sp. RAM1 was isolated from the Red Sea Bohadschia graeffei collected from Marsa Alam, Egypt, and used for carotenoids production. The extracted carotenoids were purified by thin-layer chromatography (TLC). The characteristic UV absorbance of the three purified fractions gave us an inkling of what the purified pigments were. The chemical structures were confirmed by nuclear magnetic resonance spectroscopy (NMR) and LC-ESI-QTOF-MS/MS. The three different red pigments were identified as two C₅₀-carotenoids, namely bisanhydrobacterioruberin and trisanhydrobacterioruberin, in addition to 3,4,3',4'-Tetrahydrospirilloxanthin (C₄₂-carotenoids). Kocuria sp. RAM1 carotenoids were investigated for multiple activities, including antimicrobial, anti-inflammatory, antioxidant, anti-HSV-1, anticancer, antidiabetic and wound healing. These new observations suggest that Kocuria sp. RAM1 carotenoids can be used as a distinctive natural pigment with potent properties.

Health benefits of astaxanthin against age-related diseases of multiple organs: A comprehensive review

Age-related diseases are associated with increased morbidity in the past few decades and the cost associated with the treatment of these age-related diseases exerts a substantial impact on social and health care expenditure. Anti-aging strategies aim to mitigate, delay and reverse aging-associated diseases, thereby improving quality of life and reducing the burden of age-related pathologies. The natural dietary antioxidant supplementation offers substantial pharmacological and therapeutic effects against various disease conditions. Astaxanthin is one such natural carotenoid with superior antioxidant activity than other carotenoids, as well as well as vitamins C and E, and additionally, it is known to exhibit a plethora of pharmacological effects. The present review summarizes the protective molecular mechanisms of actions of astaxanthin on age-related diseases of multiple organs such as Neurodegenerative diseases [Alzheimer's disease (AD), Parkinson's disease (PD), Stroke, Multiple Sclerosis (MS), Amyotrophic lateral sclerosis (ALS), and Status Epilepticus (SE)], Bone Related Diseases [Osteoarthritis (OA) and Osteoporosis], Cancers [Colon cancer, Prostate cancer, Breast cancer, and Lung Cancer], Cardiovascular disorders [Hypertension, Atherosclerosis and Myocardial infarction (MI)], Diabetes associated complications [Diabetic nephropathy (DN), Diabetic neuropathy, and Diabetic retinopathy (DR)], Eye disorders [Age related macular degeneration (AMD), Dry eye disease (DED), Cataract and Uveitis], Gastric Disorders [Gastritis, Colitis, and Functional dyspepsia], Kidney Disorders [Nephrolithiasis, Renal fibrosis, Renal Ischemia reperfusion (RIR), Acute kidney injury (AKI), and hyperuricemia], Liver Diseases [Nonalcoholic fatty liver disease (NAFLD), Alcoholic Liver Disease (AFLD), Liver fibrosis, and Hepatic Ischemia-Reperfusion (IR) Injury], Pulmonary Disorders [Pulmonary Fibrosis, Acute Lung injury (ALI), and Chronic obstructive pulmonary disease (COPD)], Muscle disorders (skeletal muscle atrophy), Skin diseases [Atopic dermatitis (ATD), Skin Photoaging, and Wound healing]. We have also briefly discussed astaxanthin's protective effects on reproductive health.

Chronic Inflammation in Non-Healing Skin Wounds and Promising Natural Bioactive Compounds Treatment

Chronic inflammation is one of the hallmarks of chronic wounds and is tightly coupled to immune regulation. The dysregulation of the immune system leads to continuing inflammation and impaired wound healing and, subsequently, to chronic skin wounds. In this review, we discuss the role of the immune system, the involvement of inflammatory mediators and reactive oxygen species, the complication of bacterial infections in chronic wound healing, and the still-underexplored potential of natural bioactive compounds in wound treatment. We focus on natural compounds with antioxidant, anti-inflammatory, and antibacterial activities and their mechanisms of action, as well as on recent wound treatments and therapeutic advancements capitalizing on nanotechnology or new biomaterial platforms.

Immunomodulatory Effect of Epidermal Growth Factor Secreted by Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells on Atopic Dermatitis

Background and Objectives

Human mesenchymal stem cells (MSCs) are emerging as a treatment for atopic dermatitis (AD), a chronic inflammatory skin disorder that affects a large number of people across the world. Treatment of AD using human umbilical cord blood-derived MSCs (hUCB-MSCs) has recently been studied. However, the mechanism underlying their effect needs to be studied continuously. Thus, the objective of this study was to investigate the immunomodulatory effect of epidermal growth factor (EGF) secreted by hUCB-MSCs on AD.

Methods and Results

To explore the mechanism involved in the therapeutic effect of MSCs for AD, a secretome array was performed using culture medium of hUCB-MSCs. Among the list of genes common for epithelium development and skin diseases, we focused on the function of EGF. To elucidate the effect of EGF secreted by hUCB-MSCs, EGF was downregulated in hUCB-MSCs using EGF-targeting small interfering RNA. These cells were then co-cultured with keratinocytes, Th2 cells, and mast cells. Depletion of EGF disrupted immunomodulatory effects of hUCB-MSCs on these AD-related inflammatory cells. In a Dermatophagoides farinae-induced AD mouse model, subcutaneous injection of hUCB-MSCs ameliorated gross scoring, histopathologic damage, and mast cell infiltration. It also significantly reduced levels of inflammatory cytokines including interleukin (IL)-4, tumor necrosis factor (TNF)-α, thymus and activation-regulated chemokine (TARC), and IL-22, as well as IgE levels. These therapeutic effects were significantly attenuated at all evaluation points in mice injected with EGF-depleted hUCB-MSCs.

Conclusions

EGF secreted by hUCB-MSCs can improve AD by regulating inflammatory responses of keratinocytes, Th2 cells, and mast cells.

Konjac Ceramide (kCer)-Mediated Signal Transduction of the Sema3A Pathway Promotes HaCaT Keratinocyte Differentiation

Simple Summary

Konjac ceramide (kCer) is a unique molecular species of plant-type ceramide, and is a potential Sema3A-like ligand of Nrp1. kCer suppresses histamine-stimulated cell migration of HaCaT keratinocytes. This effect of kCer is not due to histamine-activated GPCRs, but rather to Sema3A-Nrp1 receptor binding. The present study focused on the ability of kCer to induce cell differentiation, in addition to its anti-migratory effects. We demonstrated that the effects of kCer on cell migration and cell differentiation are perpetuated by a cascade of crosstalk between pathways downstream of Nrp1 and GPCR in HaCaT cells.

Abstract

Histamines suppress epidermal keratinocyte differentiation. Previously, we reported that konjac ceramide (kCer) suppresses histamine-stimulated cell migration of HaCaT keratinocytes. kCer specifically binds to Nrp1 and does not interact with histamine receptors. The signaling mechanism of kCer in HaCaT cells is also controlled by an intracellular signaling cascade activated by the Sema3A-Nrp1 pathway. In the present study, we demonstrated that kCer treatment induced HaCaT keratinocyte differentiation after migration of immature cells. kCer-induced HaCaT cell differentiation was accompanied by some features of keratinocyte differentiation markers. kCer induced activating phosphorylation of p38MAPK and c-Fos, which increased the protein levels of involucrin that was the latter differentiation marker. In addition, we demonstrated that the effects of both kCer and histamines are regulated by an intracellular mechanism of Rac1 activation/RhoA inhibition downstream of the Sema3A/Nrp1 receptor and histamine/GPCR pathways. In summary, the effects of kCer on cell migration and cell differentiation are regulated by cascade crosstalk between downstream Nrp1 and histamine-GPCR pathways in HaCaT cells.

Astaxanthin Protects Ultraviolet B-Induced Oxidative Stress and Apoptosis in Human Keratinocytes via Intrinsic Apoptotic Pathway

Background

Ultraviolet radiation causes skin damage due to increased production of reactive oxygen species (ROS) and inflammatory intermediates and direct attack of DNA of skin cells. Astaxanthin is a reddish pigment that belongs to a group of chemicals called carotenoids and has protective effects as an antioxidant.

Objective

To determine the beneficial effects of astaxanthin on damaged human skin after exposure to ultraviolet radiation.

Methods

Normal human epidermal keratinocytes (NHEKs) were pre-treated with astaxanthin for 24 hours and exposed to ultraviolet B (UVB) irradiation. After 24 hours, the Cell Counting Kit-8 (CCK-8) assay measured cell viability, ROS assay and flow cytometry analysis assessed apoptosis, and western blotting was performed to determine expression of apoptosis-related proteins.

Results

Astaxanthin significantly inhibited UVB-induced NHEKs cytotoxicity. Pretreatment of NHEKs with astaxanthin reduced UVB-induced ROS production. Astaxanthin caused significant inhibition of UVB-induced apoptosis, as evidenced by flow cytometry analysis and western blotting.

Conclusion

These results suggest that astaxanthine has a beneficial effect of reducing damage caused by UVB by effectively inhibiting cell death and reducing ROS production in keratinocytes.

Rational selection of bioactive principles for wound healing applications: Growth factors and antioxidants

Wound healing is a complex process of communication between growth factors, reactive species of oxygen, cells, signalling pathways, and cytokines in the extracellular matrix, in which growth factors are the key regulators. In humans, the main regulators of the cellular responses in wound healing are five growth factors, namely EGF, bFGF, VEGF, and TGF-β1. On the other hand, antioxidants such as astaxanthin, beta-carotene, epigallocatechin gallate, delphinidin, and curcumin have been demonstrated to stimulate cell proliferation, migration and angiogenesis, and control inflammation, to suggest a practical approach to design new strategies to treat non-healing cutaneous conditions. Based on the individual effects of growth factors and antioxidants, it may be envisioned that the use of both types of bioactives in wound healing formulations may have an additive or synergistic effect on the healing potential. This review addresses the effect of growth factors and antioxidants on wound healing-related processes. Furthermore, a prospective on their potential additive or synergistic effect on wound healing formulations, based on their individual effects, is presented. This may serve as a guide for the development of a new generation of wound healing formulations.

Protective effects of astaxanthin on lipopolysaccharide-induced inflammation in bovine endometrial epithelial cells†

Astaxanthin (AST), a natural antioxidant carotenoid, has been shown to exert anti-inflammatory effects. However, to our knowledge, no study has specifically addressed the potential protective effects of AST against bovine endometritis. The purpose of this study was to examine whether treatment with AST could protect endometrial epithelial cells against lipopolysaccharide (LPS)-induced inflammatory injury. Treatment of bovine endometrial (BEND) epithelial cell line with AST reduced LPS-induced production of interleukin-6 and tumor necrosis factor-alpha, increased the cellular activity of superoxide dismutase and catalase, decreased the proportion of apoptotic cells, and promoted the production of insulin-like growth factor and epithelial growth factor. The effects of AST were mediated through the downregulation of B-cell lymphoma 2 (Bcl-2) associated X, apoptosis regulator (Bax), and cleaved caspase-3 and through the upregulation of Bcl-2. Moreover, AST significantly increased the expression of the tight junction proteins (TJP) claudin, cadherin-1, and TJP1, which play an essential role in the maintenance of host endometrial defense barrier against pathogen infection. Collectively, these results demonstrated that treatment with AST protected against oxidative stress, prevented cell apoptosis, promoted BEND cells viability, and increased the production of growth factors, in addition to activating the endometrial defense barrier. Therefore, AST is a promising therapeutic agent for the prevention and treatment of endometritis. This finding is of utmost importance in the present times when the excessive use of antibiotics has resulted in the development of antibiotic-resistant bacteria.

In vitro antioxidant and wound-healing activities of hydrolyzed collagen from defatted Asian sea bass skin as influenced by different enzyme types and hydrolysis processes

Hydrolyzed collagen (HC) from defatted Asian sea bass skin was prepared by different enzymatic hydrolysis processes. For one-enzyme hydrolysis, papain (0.3 unit per g dry matter, DM) at 40 °C for 90 min or Alcalase (0.2 or 0.3 unit per g DM) at 50 °C for 90 min were used. The two-enzyme hydrolysis was accomplished with papain at 0.3 unit per g DM (P0.3), followed by Alcalase hydrolysis at 0.2 or 0.3 units per g DM (A0.2 or A0.3, respectively). HC prepared using the P0.3 + A0.3 process showed higher peptide yield, recovery and imino acid content in addition to stronger ABTS, DPPH radical scavenging activities and ferric reducing antioxidant power than other hydrolysis processes. HC obtained from the P0.3 + A0.3 process (at 125–500 μg mL⁻¹) induced MRC-5 fibroblast proliferation and augmented migration and lamellipodia formation in the cells. Peptides with average molecular weight of 750 Da exhibited the highest ABTS radical scavenging activity while the 4652 Da fraction had the lowest. Thus, HC can be considered as a suitable ingredient to formulate functional products for skin nourishment and wound healing.

Hydrolyzed collagen (HC) from sea bass skin prepared using papain and Alcalase had antioxidant potency and could enhance MRC-5 cell proliferation and lamellipodia formation. HC can be used as a nutraceutical or functional food ingredient.

Keratinocytes Migration Promotion, Proliferation Induction, and Free Radical Injury Prevention by 3-Hydroxytirosol

3-hydroxytyrosol (HT) is the main phenolic compound found in olive oil with known antioxidant, anti-inflammatory, and antimicrobial properties in several dermatological conditions, both when taken in the form of olive oil or pure in cosmeceutical formulations. To date, its direct effect on the wound healing process and the molecular mechanisms involved have not yet been elucidated. Thus, in the present study, we aimed to explore its effects in vitro in epidermal keratinocyte cultures focusing on the molecular mechanism implied. HT was able to induce keratinocyte proliferation in the low micromolar range, increasing the expression of cyclin dependent kinases fundamental for cell cycle progression such as CDK2 and CDK6. Furthermore, it increased cell migration through the activation of tissue remodeling factors such as matrix metalloproteinase-9 (MMP-9) protein. Then, we evaluated whether HT also showed antioxidant activity at this concentration range, protecting from H₂O₂-induced cytotoxicity. The HT prevented the activation of ATM serine/threonine kinase (ATM), Checkpoint kinase 1 (Chk1), Checkpoint kinase 2 (Chk2), and p53, reducing the number of apoptotic cells. Our study highlighted novel pharmacological properties of HT, providing the first evidence of its capability to induce keratinocyte migration and proliferation required for healing processes and re-epithelialization.

Effect of hydrolyzed collagen from defatted Asian sea bass (Lates calcarifer) skin on fibroblast proliferation, migration and antioxidant activities

Hydrolyzed collagen from the defatted Asian sea bass (Lates calcarifer) (Asbs-HC) had high hydrophobic amino acids and imino acids. When fibroblast cell was treated with Asbs-HC, there was no cytotoxicity at any concentrations (25-1000 µg/mL). Asbs-HC at 1000 µg/mL exhibited the highest cell proliferation and cell migration (p < 0.05), indicating wound healing ability. Antioxidative activities of Asbs-HC at different concentrations were determined. ABTS radical scavenging activity (ABTS-RSA) and oxygen radical absorbance capacity (ORAC) increased when Asbs-HC levels augmented up to 1 mg/mL (p < 0.05). Decreased activities in scavenging DPPH radical and chelating metal were found at higher levels of Asbs-HC (0.5 and 1 mg/mL) (p < 0.05). Molecular weight (MW) of peptides in Asbs-HC ranged from 406 to 16,120 Da. Peptide containing MW of 406 Da rendered the highest scavenging activity towards ABTS radical. Thus, Asbs-HC could be applied as antioxidant, skin nourishment and wound healing agents for food/drink fortification.

Potential Antioxidant and Wound Healing Effect of Nano-Liposol with High Loading Amount of Astaxanthin

Background

Astaxanthin (ASTA), a carotenoid, is a strong antioxidant. However, its application in functional foods, pharmaceuticals, and cosmetics remains limited due to its low aqueous solubility and stability. Several different encapsulating materials have been used to improve the stability and bioavailability of ASTA; however, the currently investigated nano-carriers for ASTA require additional improvements with regard to their loading capacity and stability.

Methods

In this study, we developed lecithin nano-liposol (Lec NS) as a novel carrier of ASTA using a simple emulsion evaporation method. The physicochemical characteristics including hydrodynamic diameter, polydispersity index, surface charge and morphology were analyzed by DLS and TEM. The antioxidant activity of the ASTA-loaded Lec NS (ASTA@Lec NS) was evaluated using a DPPH radical scavenging assay and in vitro antioxidant assay. The study of in vitro wound healing efficacy was carried out to observe the beneficial effect of antioxidant activity of ASTA@Lec NS on cell migration.

Results

ASTA@Lec NS showed improved stability and efficacy owing to improved aqueous solubility of ASTA inside Lec NS. Both in situ and in vitro antioxidant activities of ASTA@Lec NS were higher than that of bare ASTA and Lec NS. It also exhibited strong wound healing efficacy by regulation of ROS level in in vitro cell model.

Conclusion

This study revealed that the encapsulation of ASTA into Lec NS using a wet phase transfer enhanced its physiological stability and bioavailability for effective scavenging of reactive oxygen species.

Effects of dietary supplementation of natural astaxanthin from Haematococcus pluvialis on antioxidant capacity, lipid metabolism, and accumulation in the egg yolk of laying hens

The present study evaluated the effects of natural astaxanthin (ASTA) from Haematococcus pluvialis on the antioxidant capacity, lipid metabolism, and ASTA accumulation in the egg yolk of laying hens. Hy-Line Brown layers (n = 288, 50 wk old) were randomly assigned to 1 of 4 dietary treatment groups. Each group had 6 replicates of 12 hens each. All birds were given a corn-soybean meal-based diet containing 0, 25, 50, or 100 mg/kg ASTA for 6 wk. The results showed that the total antioxidant capacity, superoxide dismutase level, and glutathione peroxidase level in the plasma, livers, and egg yolks were significantly increased in the ASTA groups compared with those of the control group (P < 0.05), whereas the content of malondialdehyde linearly decreased (P < 0.05). The plasma levels of high-density and very-low-density lipoprotein cholesterol in the ASTA groups were significantly higher than those in the control group (P < 0.05). In addition, ASTA supplementation decreased low-density lipoprotein cholesterol and triglyceride plasma levels (P < 0.05). However, there were no significant differences in the other lipid metabolism parameters among the ASTA-supplemented groups relative to the control group except for an increase in high-density lipoprotein cholesterol in the liver. Compared with the control, dietary ASTA supplementation significantly increased the enrichment of ASTA in egg yolks at the end of week 2, 4, and 6 (P < 0.05). The mRNA expression of scavenger receptor class B type 1 (SCARB1) and very-low-density lipoprotein receptor (VLDLR) in the ASTA groups was markedly higher (P < 0.05) than that in the control group in the liver and ovaries, respectively. In conclusion, these results suggest that dietary ASTA enhances the antioxidant capacity and regulates lipid metabolism in laying hens. ASTA enrichment in egg yolks may be closely related to the upregulation of SCARB1 and VLDLR gene expression.

Quercetin Improves Inflammation, Oxidative Stress, and Impaired Wound Healing in Atopic Dermatitis Model of Human Keratinocytes

Background: Atopic dermatitis (AD) is a common inflammatory skin disease with complex pathogenesis. Natural flavonoids exhibit strong anti-inflammatory and antioxidant properties in many human diseases. In this study, the potential bioactive effect of quercetin, a polyphenolic plant-derived flavonoid, on the AD model of human keratinocytes was evaluated. Methods: Immortalized human HaCaT keratinocytes were treated with interleukin (IL) -4, -13, and tumor necrosis factor-α to mimic AD features in vitro. Then effects of quercetin on inflammation, oxidative stress, and wound healing were assessed. Results: Pretreatment of the cells with 1.5 μM of quercetin significantly reduced the expression of AD-induced IL-1β, IL-6, IL-8, and thymic stromal lymphopoietin, while it strongly enhanced the expression of superoxide dismutase-1 (SOD1), SOD2, catalase, glutathione peroxidase, and IL-10. Quercetin promoted wound healing by inducing epithelial-mesenchymal transition, which was supported by the upregulation of Twist and Snail mRNA expression. Unexpectedly, quercetin pretreatment of AD-induced cells upregulated the mRNA expression of occludin and E-cadherin, while downregulating matrix metalloproteinase 1 (MMP1), MMP2, and MMP9 expression. The pretreatment inhibited AD-induced phosphorylation of extracellular signal-regulated kinase 1/2/mitogen-activated protein kinase (ERK1/2 MAPK) and the expression of nuclear factor-kappa B (NF-κB), but it did not alter signal transducer and activator of transcription 6 (STAT6) phosphorylation. Conclusion: Quercetin may serve as a potential bioactive substance for atopic dermatitis-related symptoms through anti-inflammatory and antioxidant activities along with its acceleration of wound healing via ERK1/2 MAPK and NF-κB pathways.

Astaxanthin anticancer effects are mediated through multiple molecular mechanisms: A systematic review

During the latest decades, the interest on the effectiveness of natural compounds and their impact on human health constantly increased, especially on those demonstrating to be effective on cancer. Molecules coming from nature are currently used in chemotherapy like Taxol, Vincristine or Vinblastine, and several other natural substances have been showed to be active in reducing cancer cell progression and migration. Among them, astaxanthin, a xanthophyll red colored carotenoid, displayed different biological activities including, antinflammatory, antioxidant, proapoptotic, and anticancer effects. It can induce apoptosis through downregulation of antiapoptotic protein (Bcl-2, p-Bad, and survivin) expression and upregulation of proapoptotic ones (Bax/Bad and PARP). Thanks to these mechanisms, it can exert anticancer effects towards colorectal cancer, melanoma, or gastric carcinoma cell lines. Moreover, it possesses antiproliferative activity in many experimental models and enhances the effectiveness of conventional chemotherapic drugs on tumor cells underling its potential future use. This review provides an overview of the current knowledge on the anticancer potential of astaxanthin by modulating several molecular targets. While it has been clearly demonstrated its multitarget activity in the prevention and regression of malignant cells in in vitro or in preclinical investigations, further clinical studies are needed to assess its real potential as anticancer in humans.

Induction of keratinocyte migration by ECa 233 is mediated through FAK/Akt, ERK, and p38 MAPK signaling

Centella asiatica is widely considered the most important medicinal plant for treating and relieving skin diseases. Recently developed standardized extract of Centella asiatica ECa 233 has demonstrated positive effects on wound healing of incision and burn wound in rats. However, knowledge associated with wound healing mechanism of ECa 233 was scare. Therefore, this study aimed to investigate the effect and underlying molecular mechanisms of ECa 233 on the migration of a human keratinocyte cell line (HaCaT) using scratch wound healing assay. Formation of filopodia, a key protein in cell migration as well as signaling pathways possibly involved were subsequently assessed. It was found that HaCaT cell migration was significantly enhanced by ECa 233 in a concentration- and time-dependent manner. The filopodia formations were accordingly increased in exposure to ECa 233 at concentrations of 0.1-100 μg/ml. Furthermore, ECa 233 was found to significantly upregulate the expression of Rac1 and RhoA and to induce phosphorylation of FAK and Akt as well as ERK and p38 MAPK. Taken all together, it is suggestive that ECa 233 induces cell migration and subsequently promotes wound healing activity, through the activation of FAK, Akt, and MAPK signaling pathways thereby supporting the role of ECa 233 to be further developed for the clinical treatment of wound.