Astaxanthin induces angiogenesis through Wnt/β-catenin signaling pathway

Astaxanthin treatment decreases pro-inflammatory cytokines and improves reproductive outcomes in patients with polycystic ovary syndrome undergoing assisted reproductive technology: A randomized clinical trial

RESEARCH QUESTION

In a randomized, triple-blind, placebo-controlled clinical trial (RCT), we investigated the effect of astaxanthin (AST) on pro-inflammatory cytokines, oxidative stress (OS) markers, and assisted reproductive technology (ART) outcomes in 44 infertile Polycystic Ovary Syndrome (PCOS) patients.

DESIGN

Patients with PCOS were randomly divided into two groups. The intervention group received 6 mg AST, and the control group received placebo daily for 8 weeks. Blood samples were obtained from all patients before and after intervention and follicular fluid (FF) was collected during the ART procedure. Interleukin (IL) -6, IL-1β were evaluated from serum samples and FF and OS markers (malondialdehyde [MDA], catalase [CAT], superoxide dismutase [SOD], and reactive oxygen species [ROS]) were measured from FF. The groups were compared for ART outcomes as well.

RESULTS

A significant decrease in IL-6 and IL-1β concentrations (both, P = < 0.01) serum levels was found following AST treatment. FF cytokine levels and OS markers did not differ significantly between the groups. Reproductive outcomes, including the number of oocytes retrieved (P = 0.01), the MII oocyte count (P = 0.007), oocyte maturity rate (MII %) (P = 0.02) and number of frozen embryos (P = 0.03) significantly improved after intervention. No significant differences were found in chemical, clinical and multiple pregnancies between the groups.

CONCLUSIONS

AST pretreatment may modify inflammation and improve ART outcomes in PCOS infertile patients. Further investigations are recommended to verify these findings.

Natural products for gastric carcinoma prevention and treatment: Focus on their antioxidant stress actions in the Correa's cascade

BACKGROUND

Correa's cascade is a pathological process beginning from gastritis to gastric precancerous lesions, and finally to gastric carcinoma (GC). While the pathogenesis of GC remains unclear, oxidative stress plays a prominent role throughout the entire Correa's cascade process. Studies have shown that some natural products (NPs) could halt and even reverse the development of the Correa's cascade by targeting oxidative stress.

METHODS

To review the effects and mechanism by which NPs inhibit the Correa's cascade through targeting oxidative stress, data were collected from PubMed, Embase, Web of Science, ScienceDirect, and China National Knowledge Infrastructure databases from initial establishment to April 2023. NPs were classified and summarized by their mechanisms of action.

RESULTS

NPs, such as terpenoid, polyphenols and alkaloids, exert multistep antioxidant stress effects on the Correa's cascade. These effects include preventing gastric mucosal inflammation (stage 1), reversing gastric precancerous lesions (stage 2), and inhibiting gastric carcinoma (stage 3). NPs can directly impact the conversion of gastritis to GC by targeting oxidative stress and modulating signaling pathways involving IL-8, Nrf2, TNF-α, NF-κB, and ROS/MAPK. Among which polyphenols have been studied more and are of high research value.

CONCLUSIONS

NPs display a beneficial multi-step action on the Correa's cascade, and have potential value for clinical application in the prevention and treatment of gastric cancer by regulating the level of oxidative stress.

Extremophilic Solutions: The Role of Deinoxanthin in Counteracting UV-Induced Skin Harm

This research delved into the protective capacities of deinoxanthin, a carotenoid present in Deinococcus radiodurans, against UVA- and UVB-mediated skin damage using human fibroblast foreskin cells (HFF-1). Using the MTT assay, HFF-1 cells treated with 10 µM DNX displayed 20% and 31.7% higher viability than the positive (Vitamin C-treated) and negative (DNX-untreated) control groups, respectively, upon 100 mJ/cm2 UVB exposure. At 24 J/cm2 UVA, 20 µM DNX-treated cells showed 80.6% viability, exceeding the positive and negative control groups by 28.6% and 33.6%, respectively. Flow cytometry analysis revealed that cells treated with DNX and exposed to 24 J/cm2 UVA exhibited a 69.32% reduction in apoptotic processes compared to untreated cells. Similarly, when exposed to 100 mJ/cm2 UVB, DNX-treated cells demonstrated a 72.35% decrease in apoptotic processes relative to their untreated counterparts. DNX also displayed dose-dependent inhibition on tyrosinase activity. The study emphasized DNX's antioxidative capacity, evident in its modulation of superoxide dismutase activity and measurements of Malondialdehyde and intracellular reactive oxygen species levels. DNX-treated cells exhibited higher hydroxyproline levels, suggesting healthier collagen production. Additionally, the wound-healing assay method confirmed an accelerated healing rate in DNX-treated cells. Conclusively, DNX offers significant protection against UV-induced skin damage, emphasizing its potential for skincare and therapeutics.

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.

Halophilic Carotenoids and Breast Cancer: From Salt Marshes to Biomedicine

Breast cancer is the leading cause of death among women worldwide. Over the years, oxidative stress has been linked to the onset and progression of cancer. In addition to the classical histological classification, breast carcinomas are classified into phenotypes according to hormone receptors (estrogen receptor-RE-/progesterone receptor-PR) and growth factor receptor (human epidermal growth factor receptor-HER2) expression. Luminal tumors (ER/PR-positive/HER2-negative) are present in older patients with a better outcome. However, patients with HER2-positive or triple-negative breast cancer (TNBC) (ER/PR/HER2-negative) subtypes still represent highly aggressive behavior, metastasis, poor prognosis, and drug resistance. Therefore, new alternative therapies have become an urgent clinical need. In recent years, anticancer agents based on natural products have been receiving huge interest. In particular, carotenoids are natural compounds present in fruits and vegetables, but algae, bacteria, and archaea also produce them. The antioxidant properties of carotenoids have been studied during the last years due to their potential in preventing and treating multiple diseases, including cancer. Although the effect of carotenoids on breast cancer during in vitro and in vivo studies is promising, clinical trials are still inconclusive. The haloarchaeal carotenoid bacterioruberin holds great promise to the future of biomedicine due to its particular structure, and antioxidant activity. However, much work remains to be performed to draw firm conclusions. This review summarizes the current knowledge on pre-clinical and clinical analysis on the use of carotenoids as chemopreventive and chemotherapeutic agents in breast cancer, highlighting the most recent results regarding the use of bacterioruberin from haloarchaea.

Neuroprotective effects of astaxanthin against oxygen and glucose deprivation damage via the PI3K/Akt/GSK3β/Nrf2 signalling pathway in vitro

Astaxanthin (ATX), which is the most abundant flavonoid in propolis, has previously shown neuroprotective properties against cerebral ischaemia-induced apoptosis. However, the mechanisms by which ATX mediates its therapeutic effects are unclear. At present, we explored the underlying mechanisms involved in the protective effects of ATX via the phosphoinositide 3-kinase (PI3K)/Akt/glycogen synthase kinase 3 beta (GSK3β)/nuclear factor erythroid 2-related factor 2 (Nrf2) signalling pathway in SH-SY5Y cells. The PI3K/Akt inhibitor LY294002 and GSK3β inhibitor LiCl were employed in this study. Pre-treatment with ATX for 24 hours significantly decreased the oxygen and glucose deprivation (OGD)-induced viability loss, reduced the proportion of apoptosis and regulated OGD-mediated reactive oxygen species (ROS) production. Furthermore, ATX suppressed OGD-caused mitochondrial membrane potential and decomposition of caspase-3 to cleaved caspase-3, and heightened the B-cell lymphoma 2 (Bcl-2)/Bax ratio. PI3K/Akt/GSK3β/Nrf2 signalling pathway activation in SH-SY5Y cells was verified by Western blot. ATX and LiCl treatment raised the protein levels of p-Akt, p-GSK3β, nucleus Nrf2 and haeme oxygenase 1 (HO-1). However, these protein expression levels decreased by treatment of LY294002. The above in vitro data indicate that ATX can confer neuroprotection against OGD-induced apoptosis via the PI3K/Akt/GSK3β/Nrf2 signalling pathway.

Protective Effects of Astaxanthin Supplementation against Ultraviolet-Induced Photoaging in Hairless Mice

Ultraviolet (UV) light induces skin photoaging, which is characterized by thickening, wrinkling, pigmentation, and dryness. Astaxanthin (AST), a ketocarotenoid isolated from Haematococcus pluvialis, has been extensively studied owing to its possible effects on skin health as well as UV protection. In addition, AST attenuates the increased generation of reactive oxygen species (ROS) and capillary regression of the skeletal muscle. In this study, we investigated whether AST could protect against UV-induced photoaging and reduce capillary regression in the skin of HR-1 hairless mice. UV light induces wrinkle formation, epidermal thickening, and capillary regression in the dermis of HR-1 hairless mice. The administration of AST reduced the UV-induced wrinkle formation and skin thickening, and increased collagen fibers in the skin. AST supplementation also inhibited the generation of ROS, decreased wrinkle formation, reduced epidermal thickening, and increased the density of capillaries in the skin. We also found an inverse correlation between wrinkle formation and the density of capillaries. An association between photoaging and capillary regression in the skin was also observed. These results suggest that AST can protect against photoaging caused by UV irradiation and the inhibitory effects of AST on photoaging may be associated with the reduction of capillary regression in the skin.

Therapeutic and Protective Effects of Liposomal Encapsulation of Astaxanthin in Mice with Alcoholic Liver Fibrosis

Astaxanthin (Asta) has been demonstrated to possess anti-inflammatory, antitumor, and free radical-clearing activities. However, the poor stability and low water solubility of Asta hamper its bioavailability. The objectives of this study were to fabricate Asta-loaded liposomes (Asta-lipo) and investigate the therapeutic effects of Asta-lipo on alcoholic liver fibrosis in mice. The mice were administered with Asta-lipo or liposomes alone prior to a 3-week dose containing 30% alcohol with or without feeding with a second dose of 30% alcohol. The prepared Asta-lipo of 225.0 ± 58.3 nm in diameter, had an encapsulation efficiency of 98%. A slow release profile of 16.2% Asta from Asta-lipo was observed after a 24-h incubation. Restorative actions against alcoholic liver fibrosis were observed after oral administration of Asta-lipo for 4 weeks. Hepatic repair, followed by a second dose of 30% alcohol, suggested that Asta-lipo exerted protective and reparative effects against liver injuries induced by repeated consumption of alcohol. The changes of serum ALT and AST values were principally in consistence with the histopathologic findings. Asta-lipo exerted rapid and direct effects against repeated alcohol-induced liver disease, whereas Asta-lipo given orally could boost recovery from liver injuries obtained due to previous long-term alcohol use. These data demonstrate that Asta-lipo has applicable protective and therapeutic potential to treat alcohol-induced liver diseases.

Stabilization of Intrinsically Disordered DKK2 Protein by Fusion to RNA-Binding Domain

Intrinsic disorders are a common feature of hub proteins in eukaryotic interactomes controlling the signaling pathways. The intrinsically disordered proteins (IDPs) are prone to misfolding, and maintaining their functional stability remains a major challenge in validating their therapeutic potentials. Considering that IDPs are highly enriched in RNA-binding proteins (RBPs), here we reasoned and confirmed that IDPs could be stabilized by fusion to RBPs. Dickkopf2 (DKK2), Wnt antagonist and a prototype IDP, was fused with lysyl-tRNA synthetase (LysRS), with or without the fragment crystallizable (Fc) domain of an immunoglobulin and expressed predominantly as a soluble form from a bacterial host. The functional competence was confirmed by in vitro Wnt signaling reporter and tube formation in human umbilical vein endothelial cells (HUVECs) and in vivo Matrigel plug assay. The removal of LysRS by site-specific protease cleavage prompted the insoluble aggregation, confirming that the linkage to RBP chaperones the functional competence of IDPs. While addressing to DKK2 as a key modulator for cancer and ischemic vascular diseases, our results suggest the use of RBPs as stabilizers of disordered proteinaceous materials for acquiring and maintaining the structural stability and functional competence, which would impact the druggability of a variety of IDPs from human proteome.

The role of angiogenesis in Group 3 medulloblastoma pathogenesis and survival

Background

Of the 4 medulloblastoma subgroups, Group 3 is the most aggressive but the importance of angiogenesis is unknown. This study sought to determine the role of angiogenesis and identify clinically relevant biomarkers of tumor vascularity and survival in Group 3 medulloblastoma.

Methods

VEGFA mRNA expression and survival from several patient cohorts were analyzed. Group 3 xenografts were implanted intracranially in nude rats. Dynamic susceptibility weighted (DSC) MRI and susceptibility weighted imaging (SWI) were obtained. DSC MRI was used to calculate relative cerebral blood volume (rCBV) and flow (rCBF). Tumor vessel density and rat vascular endothelial growth factor alpha (VEGFA) expression were determined.

Results

Patient VEGFA mRNA levels were significantly elevated in Group 3 compared with the other subgroups (P < 0.001) and associated with survival. Xenografts D283, D341, and D425 were identified as Group 3 by RNA hierarchical clustering and MYC amplification. The D283 group had the lowest rCBV and rCBF, followed by D341 and D425 (P < 0.05). These values corresponded to histological vessel density (P < 0.05), rat VEGFA expression (P < 0.05), and survival (P = 0.002). Gene set enrichment analysis identified 5 putative genes with expression profiles corresponding with these findings: RNH1, SCG2, VEGFA, AGGF1, and PROK2. SWI identified 3 xenograft-independent categories of intratumoral vascular architecture with distinct survival (P = 0.004): organized, diffuse microvascular, and heterogeneous.

Conclusions

Angiogenesis plays an important role in Group 3 medulloblastoma pathogenesis and survival. DSC MRI and SWI are clinically relevant biomarkers for tumor vascularity and overall survival and can be used to direct the use of antivascular therapies for patients with Group 3 medulloblastoma.

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

BACKGROUND/OBJECTIVES

Re-epithelialization has an important role in skin wound healing. Astaxanthin (ASX), a carotenoid found in crustaceans including shrimp, crab, and salmon, has been widely used for skin protection. Therefore, we investigated the effects of ASX on proliferation and migration of human skin keratinocyte cells and explored the mechanism associated with that migration.

MATERIAL/METHOD

HaCaT keratinocyte cells were exposed to 0.25-1 µg/mL of ASX. Proliferation of keratinocytes was analyzed by using MTT assays and flow cytometry. Keratinocyte migration was determined by using a scratch wound-healing assay. A mechanism for regulation of migration was explored via immunocytochemistry and western blot analysis.

RESULTS

Our results suggest that ASX produces no significant toxicity in human keratinocyte cells. Cell-cycle analysis on ASX-treated keratinocytes demonstrated a significant increase in keratinocyte cell proliferation at the S phase. In addition, ASX increased keratinocyte motility across the wound space in a time-dependent manner. The mechanism by which ASX increased keratinocyte migration was associated with induction of filopodia and formation of lamellipodia, as well as with increased Cdc42 and Rac1 activation and decreased RhoA activation.

CONCLUSIONS

ASX stimulates the migration of keratinocytes through Cdc42, Rac1 activation and RhoA inhibition. ASX has a positive role in the re-epithelialization of wounds. Our results may encourage further in vivo and clinical study into the development of ASX as a potential agent for wound repair.

Effect of astaxanthin on cutaneous wound healing

Wound healing consists of a complex series of convoluted processes which involve renewal of the skin after injury. ROS are involved in all phases of wound healing. A balance between oxidative and antioxidative forces is necessary for a favorable healing outcome. Astaxanthin, a member of the xanthophyll group, is considered a powerful antioxidant. In this study, we investigated the effect of topical astaxanthin on cutaneous wound healing. Full-thickness dermal wounds were created in 36 healthy female mice, which were divided into a control group and a group receiving 78.9 µM topical astaxanthin treatment twice daily for 15 days. Astaxanthin-treated wounds showed noticeable contraction by day 3 of treatment and complete wound closure by day 9, whereas the wounds of control mice revealed only partial epithelialization and still carried scabs. Wound healing biological markers including Col1A1 and bFGF were significantly increased in the astaxanthin-treated group since day 1. Interestingly, the oxidative stress marker iNOS showed a significantly lower expression in the study. The results indicate that astaxanthin is an effective compound for accelerating wound healing.

Gene expression profiles of brain endothelial cells during embryonic development at bulk and single-cell levels

The blood-brain barrier is a dynamic interface that separates the brain from the circulatory system, and it is formed by highly specialized endothelial cells. To explore the molecular mechanisms defining the unique nature of vascular development and differentiation in the brain, we generated high-resolution gene expression profiles of mouse embryonic brain endothelial cells using translating ribosome affinity purification and single-cell RNA sequencing. We compared the brain vascular translatome with the vascular translatomes of other organs and analyzed the vascular translatomes of the brain at different time points during embryonic development. Because canonical Wnt signaling is implicated in the formation of the blood-brain barrier, we also compared the brain endothelial translatome of wild-type mice with that of mice lacking the transcriptional cofactor β-catenin (Ctnnb1). Our analysis revealed extensive molecular changes during the embryonic development of the brain endothelium. We identified genes encoding brain endothelium-specific transcription factors (Foxf2, Foxl2, Foxq1, Lef1, Ppard, Zfp551, and Zic3) that are associated with maturation of the blood-brain barrier and act downstream of the Wnt-β-catenin signaling pathway. Profiling of individual brain endothelial cells revealed substantial heterogeneity in the population. Nevertheless, the high abundance of Foxf2, Foxq1, Ppard, or Zic3 transcripts correlated with the increased expression of genes encoding markers of brain endothelial cell differentiation. Expression of Foxf2 and Zic3 in human umbilical vein endothelial cells induced the production of blood-brain barrier differentiation markers. This comprehensive data set may help to improve the engineering of in vitro blood-brain barrier models.

Berberine promotes proliferation of sodium nitroprusside-stimulated rat chondrocytes and osteoarthritic rat cartilage via Wnt/β-catenin pathway

Berberine chloride (BBR) is an isoquinoline derivative alkaloid isolated from medicinal herbs, including Coptis chinensis and Berberis aristate. This compound plays significant roles in the treatment of osteoarthritis (OA). The purpose of this study was to investigate the effects of BBR on the proliferation of sodium nitroprusside (SNP)-stimulated chondrocytes in vitro, the articular cartilage in a rat OA model, as well as to discuss the molecular mechanisms underlying these effects. In vitro, we demonstrated that BBR led to cell proliferation, increased the cell population in S-phase and decreased that in G0/G1-phase; moreover, the F-actin remodeling in SNP-stimulated chondrocytes were prevented. In addition, BBR markedly up-regulated β-catenin, c-Myc, and cyclin D1 expression of genes and proteins, and down-regulated glycogen synthase kinase-3β (GSK-3β) and matrix metalloproteinase-7 (MMP-7) expression. Notably, inhibition of the Wnt/β-catenin pathway by XAV939 partially blocked these effects. The in vivo results suggested that BBR promoted β-catenin protein level and enhanced proliferating cell nuclear antigen (PCNA) expression in osteoarthritic rat cartilage. In conclusion, these findings indicate that BBR promotes SNP-stimulated chondrocyte proliferation by promoting G1/S phase transition and synthesis of PCNA in cartilage through activation of Wnt/β-catenin signaling pathway.