Astaxanthin protects against early burn-wound progression in rats by attenuating oxidative stress-induced inflammation and mitochondria-related apoptosis

Astaxanthin Modulation of Signaling Pathways That Regulate Autophagy

Autophagy is a lysosomal pathway that degrades and recycles unused or dysfunctional cell components as well as toxic cytosolic materials. Basal autophagy favors cell survival. However, the aberrant regulation of autophagy can promote pathological conditions. The autophagy pathway is regulated by several cell-stress and cell-survival signaling pathways that can be targeted for the purpose of disease control. In experimental models of disease, the carotenoid astaxanthin has been shown to modulate autophagy by regulating signaling pathways, including the AMP-activated protein kinase (AMPK), cellular homolog of murine thymoma virus akt8 oncogene (Akt), and mitogen-activated protein kinase (MAPK), such as c-Jun N-terminal kinase (JNK) and p38. Astaxanthin is a promising therapeutic agent for the treatment of a wide variety of diseases by regulating autophagy.

Astaxanthin Protects OTA-Induced Lung Injury in Mice through the Nrf2/NF-κB Pathway

The aim of this research was to evaluate the potential protective mechanism of astaxanthin (ASTA) against oxidative damage and inflammation caused by ochratoxin (OTA) in mouse lung. We divided mice into a control group (CG), an OTA group (PG), an astaxanthin group (AG), and an OTA+ASTA group (JG). Oxidative indices (malondialdehyde (MDA), total superoxide dismutase (T-SOD), and reduced glutathione (GSH)) and inflammatory markers (interleukin 1β (IL-1β), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α)) were assayed in the lung, and the lung-weight-to-body-weight ratio was calculated. Apoptosis was detected in pathological sections by the TdT-mediated dUTP nick-end labeling (TUNEL) assay. Oxidative damage and inflammation were detected in the lung of mice after exposure to OTA. Besides, Nrf2- and NF-κB-pathway-associated proteins were detected by Western blot. In contrast with OTA, ASTA significantly raised the expression of Nrf2, HO-1, and MnSOD, while the expression of other proteins (Keap1, TLR4, and NF-κB) was significantly decreased. These results indicate that ASTA exerted protective effects against OTA-induced oxidative damage and inflammation in the lung by regulating the Nrf2 and NF-κB pathways.

Protective effects of astaxanthin on skin: Recent scientific evidence, possible mechanisms, and potential indications

Astaxanthin is a naturally occurring ketocarotenoid which has been found to have numerous biological functions, with its strong antioxidant property being the prominent feature. The compound has attracted a great amount of interest with respect to its potential utilization in the betterment of human health. In the recent past, astaxanthin has been extensively studied with respect to its possible effect on skin health, with positive results. Astaxanthin has also shown to have anti-inflammatory, immune-modulating, and DNA repair properties, which have further encouraged its usage to maintain skin health and tackle skin damage. In this review article, we highlight the pharmacokinetic profile of the antioxidant in brief and describe the findings of various recent published research articles which studied the effect of astaxanthin in improvement of skin health. We also mention the possible mechanisms which form the basis of the positive dermatological effects of astaxanthin and the potential indications of the antioxidant molecule in cosmetology and dermatology.

Glucocorticoids suppress fibroblast apoptosis in an in vitro thermal injury model

The wounds of full- and deep partial-thickness burns result in hypertrophic scars and lead to skin contracture more severely than those of superficial partial-thickness burns. Therefore, preventing burn progression may help improve the aesthetic and functional outcomes after healing. Although a number of studies have focused on elucidating the underlying mechanisms of and preventing burn wound progression, it is still difficult to rescue burned dermis unless early tangential excision is performed. To investigate the underlying mechanisms of and prevent cell death of heat-injured fibroblasts, we developed an in vitro experimental model of heat-injured fibroblasts. We confirmed that heating at 55°C for 30s caused fibroblast necrosis immediately after heating, whereas heating at 46°C for 30s induced apoptosis 24h after heating. We also found that the supplementation of 100ng/ml betamethasone to the culture medium after heating decreased the number of apoptotic cells and increased that of live cells. Our studies suggest that glucocorticoids suppress apoptosis of heat-injured fibroblasts and may be useful for preventing burn wound progression.

Burn-induced Oxidative Stress and Serum Glutathione Depletion; a Cross Sectional Study

INTRODUCTION

Several studies have shown the role of oxidative stress in pathophysiology of burn injuries. This study aimed to evaluate the changes of oxidant-antioxidant levels during the week following burn injuries and its correlation with grade of burn.

METHODS

In this prospective cross-sectional study, changes of total glutathione, reduced glutathione (GSH), oxidized GSH (GSSG), GSH/GSSG ratio, as well as Pro-oxidant-antioxidant balance (PAB) were investigated on the 1^st, 2^nd and 7^th days of admission in patients with > 15 % burns.

RESULTS

40 patients with the mean age of 21.1 ± 14.5 were studied (47.5% male). More than 50% of patients were in the 18 - 55 years age range and over 70% had 20% - 60% grade of burn. Total serum glutathione level and GSH had significant decreasing trends (P < 0.001) and GSSG and GSH/GSSG ratio had increasing trends (p < 0.001). No significant correlation was observed between serum GSH level and the total body surface area (TBSA) of burn injury (r = 0.047; p = 0.779). The evaluation of PAB and its correlation with TBSA showed a significant and direct association between them on the 1^st (coefficient = 0.516; p = 0.001), 2^nd (coefficient = 0.62; p <0.001), and 3^rd (coefficient = 0.471; p = 0.002) day of follow up.

CONCLUSION

According to this study, the redox perturbation occurred in burn injury which was measured and proved by decreased GSH/GSSG ratio as well as the shift of PAB in favour of oxidants. Besides, since PAB positively correlated with the severity of dermal damage, it might suggest the application of antioxidants as a part of therapeutic protocol for which the dosage should be proportionate to the surface area of the damaged skin.

Inhibitory Effect of Astaxanthin on Oxidative Stress-Induced Mitochondrial Dysfunction-A Mini-Review

Oxidative stress is a major contributor to the pathogenesis of various human diseases as well as to the aging process. Mitochondria, as the center of cellular metabolism and major regulators of redox balance, play a critical role in disease development and progression. Mitochondrial dysfunction involving structural and metabolic impairment is prominent in oxidative stress-related diseases. Increased oxidative stress can damage mitochondria, and subsequent mitochondrial dysfunction generates excesses of mitochondrial reactive oxygen species that cause cellular damage. Mitochondrial dysfunction also activates the mitochondrial apoptotic pathway, resulting in cellular death. Astaxanthin, a red-colored xanthophyll carotenoid, exerts an anti-oxidative and anti-inflammatory effect on various cell lines. In this manner astaxanthin maintains mitochondrial integrity under various pathological conditions. In this review, the inhibitory effects of astaxanthin on oxidative stress-induced mitochondrial dysfunction and related disease development are discussed.

The Protective Role of Astaxanthin for UV-Induced Skin Deterioration in Healthy People-A Randomized, Double-Blind, Placebo-Controlled Trial

Skin is a major safeguard tissue in humans. Because biological barrier function is deteriorated by several kinds of stresses including exposure to ultra-violet (UV) rays, the protection and treatment of skin conditions by dietary supplements are important. We therefore evaluated the effects of dietary supplementation with an algal food-derived antioxidant, astaxanthin, on UV-induced skin deterioration. Twenty-three healthy Japanese participants were recruited to a 10-week double-blind placebo-controlled study. They were assigned to the astaxanthin group supplemented with a capsule containing 4 mg of astaxanthin or the placebo group. To assess the protective role of astaxanthin for UV-induced skin deterioration, we determined the minimal erythema dose (MED) and analyzed UV-induced changes of moisture and transepidermal water loss (TEWL) at baseline and after 9 weeks of supplementation. Subjective skin conditions were assessed by the visual analog scale. The astaxanthin group showed increased MED compared with placebo. In addition, the astaxanthin group had a reduced loss of skin moisture in the irradiated area compared with placebo. Subjective skin conditions for “improvement of rough skin” and “texture” in non-irradiated areas were significantly improved by astaxanthin. Astaxanthin seems protective against UV-induced skin deterioration and helps maintain healthy skin in healthy people.

Synthesis, stability and bioavailability of astaxanthin succinate diester

BACKGROUND

We synthesized astaxanthin succinate diester (ASD), a novel astaxanthin (AST) derivate, with succinic anhydride and free AST. ASD was purified and characterized using silica gel column chromatography and spectrometry, respectively.

RESULTS

The ASD final synthesis rate was 82.63%. A stability test revealed a high AST and ASD retention rate at pH 5.0-7.0. ASD showed better stability than did AST under acidic conditions. Both sample ions showed lower retention rates under Fe²⁺ and Fe³⁺ states. The ASD metabolic curve showed serum and liver area under the curve from 0 h to time t (AUC_0-t ) values of 45.05 ± 4.58 and 120.38 ± 23.66 µg h^-1  mL^-1 , respectively. The long-term accumulation was significantly higher in the ASD group than in the AST group, which showed higher accumulation in the heart, muscle and spleen than in other tissues in vivo.

CONCLUSION

The thermal stability and bioavailability of ASD were higher than that of the non-esterified free AST and common free AST, respectively. Additionally, AST accumulation in different tissues of the ASD group was multifold higher than that of free AST. These results prove that ASD may serve as a better source of AST for human nutrition than does free AST. © 2017 Society of Chemical Industry.

Astaxanthin in Skin Health, Repair, and Disease: A Comprehensive Review

Astaxanthin, a xanthophyll carotenoid, is a secondary metabolite naturally synthesized by a number of bacteria, microalgae, and yeasts. The commercial production of this pigment has traditionally been performed by chemical synthesis, but the microalga Haematococcus pluvialis appears to be the most promising source for its industrial biological production. Due to its collective diverse functions in skin biology, there is mounting evidence that astaxanthin possesses various health benefits and important nutraceutical applications in the field of dermatology. Although still debated, a range of potential mechanisms through which astaxanthin might exert its benefits on skin homeostasis have been proposed, including photoprotective, antioxidant, and anti-inflammatory effects. This review summarizes the available data on the functional role of astaxanthin in skin physiology, outlines potential mechanisms involved in the response to astaxanthin, and highlights the potential clinical implications associated with its consumption.

Astaxanthin mitigates cobalt cytotoxicity in the MG-63 cells by modulating the oxidative stress

Background

With the re-popularity of metal-on-metal (MoM) bearing in recent years, the cobalt toxicity has been a cause for concern in the total hip replacement surgery by both physicians and patients.

Methods

MG-63 cell line was cultured in vitro and incubated with cobalt (II) chloride (CoCl₂) and/or with astaxanthin (ASX) for 24 h. MTT assay was conducted to evaluate the cell viability after cobalt exposure and ASX treatment. Fluorescence-activated cell sorting (FACS) analysis was performed to examine the reactive oxygen species (ROS) level. Quantitative real-time polymerase chain reaction (PCR) was adopted to determine the mRNA levels of related targets. And western blot analysis was used to examine the protein expressions. One-way ANOVA with posttest Newman-Keuls multiple comparisons was adopted to analysis all the obtained data.

Results

In the current study, ASX exhibited significant protective effect against the Co(II)-induced cytotoxicity in MG-63 cell line. We also found that ASX protected the cells against Co-induced apoptosis by regulating the expression of Bcl-2 family proteins. Besides, heme oxygenase 1 (HO-1) could be activated by Co exposure; ASX treatment significantly inhibited HO-1 activation, suppressing the oxidative stress induced by Co exposure. Moreover, c-Jun N-terminal Kinase (JNK) phosphorylation was shown to participate in the signaling pathway of the protective effect of ASX. However, knockdown of JNK expression by siRNA transfection or JNK inhibitor SP600125 treatment did not affect the protective effect of ASX against cobalt cytotoxicity in MG-63 cells.

Conclusions

ASX mitigated cobalt cytotoxicity in the MG-63 cells by modulating the oxidative stress. And ASX could be a promising therapy against cobalt toxicity in the hip articulation surgery.

Electronic supplementary material

The online version of this article (doi:10.1186/s40360-017-0166-1) contains supplementary material, which is available to authorized users.