Astaxanthin and its Effects in Inflammatory Responses and Inflammation-Associated Diseases: Recent Advances and Future Directions

Astaxanthin attenuates diabetic kidney injury through upregulation of autophagy in podocytes and pathological crosstalk with mesangial cells

Objectives: Astaxanthin (ATX) is a strong antioxidant drug. This study aimed to investigate the effects of ATX on podocytes in diabetic nephropathy and the underlying renal protective mechanism of ATX, which leads to pathological crosstalk with mesangial cells.Methods: In this study, diabetic rats treated with ATX exhibited reduced 24-h urinary protein excretion and decreased blood glucose and lipid levels compared to vehicle-treated rats. Glomerular mesangial matrix expansion and renal tubular epithelial cell injury were also attenuated in ATX-treated diabetic rats compared to control rats.Results: ATX treatment markedly reduced the α-SMA and collagen IV levels in the kidneys of diabetic rats. Additionally, ATX downregulated autophagy levels. In vitro, compared with normal glucose, high glucose inhibited LC3-II expression and increased p62 expression, whereas ATX treatment reversed these changes. ATX treatment also inhibited α-SMA and collagen IV expression in cultured podocytes. Secreted factors (vascular endothelial growth factor B and transforming growth factor-β) generated by high glucose-induced podocytes downregulated autophagy in human mesangial cells (HMCs); however, this downregulation was upregulated when podocytes were treated with ATX.Conclusions: The current study revealed that ATX attenuates diabetes-induced kidney injury likely through the upregulation of autophagic activity in podocytes and its antifibrotic effects. Crosstalk between podocytes and HMCs can cause renal injury in diabetes, but ATX treatment reversed this phenomenon.

Krill oil supplementation for knee pain: a systematic review and meta-analysis with trial sequential analysis of randomized controlled trials

INTRODUCTION

Knee pain is a major cause of disability worldwide, particularly among the elderly. Current treatments, including nonsteroidal anti-inflammatory drugs and analgesics, often lead to adverse effects. Krill oil is being explored as a potential alternative, however its efficacy in managing knee symptoms remains unclear.

METHODS

MEDLINE, Embase, and Cochrane databases were searched until May 2024 for studies comparing krill oil and placebo in knee pain patients. Endpoints included knee pain, stiffness, physical function, and lipid profiles (HDL-C, LDL-C, triglycerides, and total cholesterol). A restricted maximum likelihood random-effects model with standardized mean differences (SMD) and 95% confidence intervals (CI) was used. A trial sequential analysis was conducted to evaluate further research implications.

RESULTS

We included five trials with 700 patients using krill oil for knee pain. Results showed no significant difference between krill oil and placebo for knee pain, knee stiffness, and lipid profiles. However, krill oil demonstrated a significant small effect in improving knee physical function (SMD -0.24, 95% CI [-0.41; -0.08], I2 = 0%).Trial sequential analysis provided certainty that krill oil enhances knee physical function compared to placebo and indicated no improvement in knee pain, but the findings for knee stiffness need to be confirmed by further research.

CONCLUSION

This study found that krill oil supplementation did not significantly improve knee pain, stiffness, or lipid profile, although it may help knee physical function. Based on these findings, krill oil supplementation is not yet justified for knee pain.

Exploring Extremotolerant and Extremophilic Microalgae: New Frontiers in Sustainable Biotechnological Applications

Exploring extremotolerant and extremophilic microalgae opens new frontiers in sustainable biotechnological applications. These microorganisms thrive in extreme environments and exhibit specialized metabolic pathways, making them valuable for various industries. The study focuses on the ecological adaptation and biotechnological potential of these microalgae, highlighting their ability to produce bioactive compounds under stress conditions. The literature reveals that extremophilic microalgae can significantly enhance biomass production, reduce contamination risks in large-scale systems, and produce valuable biomolecules such as carotenoids, lipids, and proteins. These insights suggest that extremophilic microalgae have promising applications in food, pharmaceutical, cosmetic, and biofuel industries, offering sustainable and efficient alternatives to traditional resources. The review concludes that further exploration and utilization of these unique microorganisms can lead to innovative and environmentally friendly solutions in biotechnology.

A Focus on the Proximal Tubule Dysfunction in Dent Disease Type 1

Dent disease type 1 is a rare X-linked recessive inherited renal disorder affecting mainly young males, generally leading to end-stage renal failure and for which there is no cure. It is caused by inactivating mutations in the gene encoding ClC-5, a 2Cl-/H+ exchanger found on endosomes in the renal proximal tubule. This transporter participates in reabsorbing all filtered plasma proteins, which justifies why proteinuria is commonly observed when ClC-5 is defective. In the context of Dent disease type 1, a proximal tubule dedifferentiation was shown to be accompanied by a dysfunctional cell metabolism. However, the exact mechanisms linking such alterations to chronic kidney disease are still unclear. In this review, we gather knowledge from several Dent disease type 1 models to summarize the current hypotheses generated to understand the progression of this disorder. We also highlight some urinary biomarkers for Dent disease type 1 suggested in different studies.

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.

Astaxanthin ameliorated isoproterenol induced myocardial infarction via improving the mitochondrial function and antioxidant activity in rats

The present study evaluated the cardioprotective effect of astaxanthin (ASX) against isoproterenol (ISO) induced myocardial infarction in rats via the pathway of mitochondrial biogenesis as the possible molecular target of astaxanthin. The control group was injected with normal physiological saline subcutaneously for 2 days. The second group was injected with ISO at a dose of 85 mg/kg bwt subcutaneously for 2 days. The third, fourth and fifth groups were supplemented with ASX at doses of 10, 20, 30 mg/kg bwt, respectively daily by oral gavage for 21 days then injected with ISO dose of 85 mg/kg bwt subcutaneously for 2 successive days. Isoproterenol administration in rats elevated the activities of Creatine kinase-MB (CK-MB), aspartate transaminase (AST), lactate dehydrogenase (LDH), and other serum cardiac biomarkers Troponin-I activities, oxidative stress biomarkers, malondialdehyde(MDA), Nuclear factor-kappa B (NF-KB), while it decreased Peroxisome proliferator-activated receptor-gamma coactivator (PGC-1α), Nuclear factor erythroid-2-related factor 2 (Nfe212), mitochondrial transcriptional factor A (mt TFA), mitochondrial DNA copy number and glutathione system parameters. However, Astaxanthin decreased the activities of serum AST, LDH, CK-MB, and Troponin I that elevated by ISO. In addition, it increased glutathione peroxidase and reductase activities, total glutathione and reduced GSH content, and GSH/GSSG ratio, mtDNA copy number, PGC-1α expression and Tfam expression that improved mitochondrial biogenesis while it decreased GSSG and MDA contents and NF-KB level in the cardiac tissues. This study indicated that astaxanthin relieved isoproterenol induced myocardial infarction via scavenging free radicals and reducing oxidative damage and apoptosis in cardiac tissue.

Anti-Inflammatory and Antioxidant Properties of a New Mixture of Vitamin C, Collagen Peptides, Resveratrol, and Astaxanthin in Tenocytes: Molecular Basis for Future Applications in Tendinopathies

Tendinopathy is one of the most frequent musculoskeletal disorders characterized by sustained tissue inflammation and oxidative stress, accompanied by extracellular matrix remodeling. Patients suffering from this pathology frequently experience pain, swelling, stiffness, and muscle weakness. Current pharmacological interventions are based on nonsteroidal anti-inflammatory drugs; however, the effectiveness of these strategies remains ambiguous. Accumulating evidence supports that oral supplementation of natural compounds can provide preventive, and possibly curative, effects. Vitamin C (Vit C), collagen peptides (Coll), resveratrol (Res), and astaxanthin (Asx) were reported to be endowed with potential beneficial effects based on their anti-inflammatory and antioxidant activities. Here, we analyzed the efficacy of a novel combination of these compounds (Mix) in counteracting proinflammatory (IL-1β) and prooxidant (H2O2) stimuli in human tenocytes. We demonstrated that Mix significantly impairs IL-6-induced IL-1β secretion, NF-κB nuclear translocation, and MMP-2 production; notably, a synergistic effect of Mix over the single compounds could be observed. Moreover, Mix was able to significantly counteract H2O2-triggered ROS production. Together, these results point out that Mix, a novel combination of Vit C, Coll, Resv, and Asx, significantly impairs proinflammatory and prooxidant stimuli in tenocytes, mechanisms that contribute to the onset of tendinopathies.

Astaxanthin Supplementation Does Not Alter Training-Related Changes in Inflammatory Cytokine Profile in Arabian Racing Horses

This study aimed to evaluate the oral supplementation of astaxanthin (ATX) on inflammatory markers in 3-year-old Arabian racehorses. Despite the recognized antioxidant and anti-inflammatory properties of ATX observed in vitro in rodent models and in human athletes, the effects in equine subjects remain unknown. This study involved a controlled trial with 14 horses receiving either ATX (six horses) or a placebo (eight horses), monitored over four months of race training. Inflammatory cytokines: TNFα, IFNγ, IL-6, IL-10, and prostaglandin E (PGE), were measured monthly to assess the impact of ATX on the inflammatory response. The results indicated no significant differences in measured parameters between the ATX and the control group during the study. However, a significant time-dependent decrease in TNFα and IFNγ levels (p = 0.001) was observed in both groups, suggesting that regular training naturally modulates inflammatory responses. Moreover, positive correlations were noted between TNFα and IFNγ (p < 0.001) in the early phase of the study and between IL-6 and IL-10 (p = 0.008) in the later phase. Hematological parameters remained stable and within reference ranges, indicating no adverse effects of ATX supplementation. Performance metrics, including the number of races completed and wins, showed no significant differences between groups, suggesting that ATX did not enhance athletic performance under the study conditions. Overall, while ATX supplementation affected neither cytokine levels nor performance in Arabian racehorses, the natural anti-inflammatory effects of regular training were evident. Further research is needed to explore potential benefits of ATX supplementation under different conditions, such as in horses with subclinical inflammation or varying training regimens, to fully clarify its role and applications in equine sports medicine.

Phytonutrients in the promotion of healthspan: a new perspective

Considering a growing, aging population, the need for interventions to improve the healthspan in aging are tantamount. Diet and nutrition are important determinants of the aging trajectory. Plant-based diets that provide bioactive phytonutrients may contribute to offsetting hallmarks of aging and reducing the risk of chronic disease. Researchers now advocate moving toward a positive model of aging which focuses on the preservation of functional abilities, rather than an emphasis on the absence of disease. This narrative review discusses the modulatory effect of nutrition on aging, with an emphasis on promising phytonutrients, and their potential to influence cellular, organ and functional parameters in aging. The literature is discussed against the backdrop of a recent conceptual framework which describes vitality, intrinsic capacity and expressed capacities in aging. This aims to better elucidate the role of phytonutrients on vitality and intrinsic capacity in aging adults. Such a review contributes to this new scientific perspective-namely-how nutrition might help to preserve functional abilities in aging, rather than purely offsetting the risk of chronic disease.

Krill oil: nutraceutical potential in skin health and disease

Krill oil (KO), extracted from the Antarctic marine crustacean Euphausia superba, is a nutrient-dense substance that includes rich profiles of n-3 polyunsaturated fatty acids (n-3 PUFAs), phospholipids (PLs), astaxanthin (ASX), as well as vitamins A and E, minerals, and flavonoids. As a high-quality lipid resource, KO has been widely used as a dietary supplement for its health-protective properties in recent years. KO has various benefits, including antioxidative, anti-inflammatory, metabolic regulatory, neuroprotective, and gut microbiome modulatory effects. Especially, the antioxidant and anti-inflammatory effects make KO have potential in skin care applications. With increasing demands for natural skin anti-aging solutions, KO has emerged as a valuable nutraceutical in dermatology, showing potential for mitigating the effects of skin aging and enhancing overall skin health and vitality. This review provides an overview of existing studies on the beneficial impact of KO on the skin, exploring its functional roles and underlying mechanisms through which it contributes to dermatological health and disease management.

Effects of Astaxanthin Supplementation on Fatigue, Motor Function and Cognition: A Meta-Analysis of Randomized Controlled Trials

Dietary astaxanthin supplementation has been demonstrated to have many beneficial and health-promoting effects. The purpose of this systematic review and meta-analysis was to assess the effect of astaxanthin supplementation on fatigue, cognition, and exercise efficiency. A total of 11 randomized controlled trials (RCTs) with 346 healthy participants were included. The random effects model and pooled standardized mean difference (SMDs) were used according to Hedge's g for the meta-analysis, and a meta-regression was also conducted. The results of the two existing studies showed a positive trend for astaxanthin in subjective fatigue relief. The effects of astaxanthin supplementation for 8-12 weeks on cognitive accuracy were marginally significant (SMD: .12; 95% CI: -.02-.26) and on reaction time was not significant (SMD: -.08; 95% CI: -.26 to .10). Remarkably, astaxanthin supplementation combined with regular training could enhance the fat oxidation (SMD: 2.56; 95% CI: 1.24-3.89), and significantly improve the physical performance (SMD: .62; 95% CI: .17-1.06). The subgroup analysis further showed significantly greater benefits when performing the aerobic exercises performance (SMD: .45; 95% CI: .13-.76), when the dose was ≥ 20 mg (SMD: .37; 95% CI: .11-.63), and when the supplementation duration was > 12 weeks (SMD: .66; 95% CI: .13-.63). We conclude that astaxanthin supplementation could significantly enhance aerobic exercise efficiency, especially at higher doses and for longer durations. Further studies based on large sample sizes are imperatively warranted.

Randomized clinical trial of astaxanthin supplement on serum inflammatory markers and ER stress-apoptosis gene expression in PBMCs of women with PCOS

Polycystic ovarian syndrome (PCOS) is related to pro-apoptotic and pro-inflammatory conditions generated by Endoplasmic reticulum (ER) stress. This study aimed to determine the effect of Astaxanthin (ASX), as carotenoid with potent antioxidant and anti-inflammatory properties, on serum inflammatory markers, apoptotic factors and ER stress-apoptotic genes in peripheral blood mononuclear cells (PBMCs) of women with PCOS. This randomized, double-blind clinical trial included 56 PCOS patients aged 18-40. For 8 weeks, subjects were randomly assigned to one of two groups: either 12 mg ASX (n = 28) or placebo (n = 28). Real-time PCR was used to quantify gene expression associated with ER stress-apoptosis in PCOS women's PBMCs. The levels of TNF-α, IL18, IL6 and CRP were determined by obtaining blood samples from all patients before and after the intervention using Enzyme-linked immunosorbent assay (ELISA). Also, the levels of active caspase-3 and caspase-8 were detected in the PBMC by ELISA kit. Furthermore, we evaluated the efficacy of ASX on disease symptoms. Following the 8-week intervention, ASX supplementation was able to reduce the expression of GRP78 (p = 0.051), CHOP (p = 0.008), XBP1 (p = 0.002), ATF4 (0.038), ATF6 (0.157) and DR5 (0.016) when compared to the placebo. However, this decrease was not statistically significant for ATF6 (p = 0.067) and marginally significant for GRP78 (p = 0.051). The levels of TNF-α (p = 0.009), IL-18 (p = 0.003), IL-6 (p = 0.013) and active caspase-3 (p = 0.012) were also statistically significant lower in the therapy group. However, there was no significant difference in CRP (p = 0.177) and caspase-8 (p = 0.491) levels between the treatment and control groups. In our study, ASX had no significant positive effect on BMI, hirsutism, hair loss and regularity of the menstrual cycle. It appears that ASX may benefit PCOS by changing the ER stress-apoptotic pathway and reducing serum inflammatory markers; however, additional research is required to determine this compound's potential relevance.

Triterpenes G-A and G-E from Galphimia glauca with anti-inflammatory and anti-arthritic activity in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Galphimia glauca is a medicinal plant that treats inflammatory and anti-rheumatic problems. Its anti-inflammatory capacity has been reported pharmacologically, attributed to the triterpenes G-A and G-E.

AIM

The objective of the present work was to measure the anti-inflammatory and immunomodulatory effect of the methanolic extract (GgMeOH) of Galphimia glauca and the isolated galphimines G-A and G-E, first in an acute test of plantar edema with carrageenan, and later in the model of experimental-induced arthritis with CFA. The effect was measured by quantifying joint inflammation, the concentration of pro- (TNF-α, IL-6, IL-17) and anti-inflammatory (IL-10, and IL-4) cytokines, and the ADA enzyme in joints, kidneys, and spleen from mice with experimental arthritis.

METHOD

The extract and the active triterpenes were obtained according to established methods using different chromatographic techniques. Female ICR strain mice were subjected to intraplantar administration with carrageenan and treated with different doses of GgMeOH, G-A, and G-E; edema was monitored at different times. Subsequently, the concentration of TNF-a and IL-10 in the spleen and swollen paw was quantified. Meloxicam (MEL) was used as an anti-inflammatory control drug. The most effective doses of each treatment were analyzed using a complete Freunds adjuvant (CFA)-induced experimental arthritis model. Joint inflammation was followed throughout the experiment. Ultimately, the concentration of inflammation markers, oxidant stress, and ADA activity was quantified. In this experimental stage, methotrexate (MTX) was used as an antiarthritic drug.

RESULTS

Treatments derived from G. glauca, GgMeOH (DE50 = 158 mg/kg), G-A (DE50 = 2 mg/kg), and G-E (DE50 = 1.5 mg/kg) caused an anti-inflammatory effect in the plantar edema test with carrageenan. In the CFA model, joint inflammation decreased with all natural treatments; GgMeOH and G-A inhibited the ADA enzyme in all organs analyzed (joints, serum, spleen, left and right kidneys), while G-E inhibited the enzyme in joints, serum, and left kidney. CFA caused an increase in the weight index of the organs, an effect that was counteracted by the administration of G. glauca treatments, which also modulate the response to the cytokines analyzed in the different organs (IL-4, IL-10, IL-17, IL-6, and TNF- α).

CONCLUSION

It is shown, for the first time, that the GgMeOH extract and the triterpenes G-A and G-E of Galphimia glauca have an anti-arthritic effect (anti-inflammatory, immunomodulatory, antioxidant, and ADA inhibitor), using an experimental arthritis model with CFA. Therefore, knowledge of the plant as a possible therapeutic agent for this rheumatic condition is expanding.

Independent and combined effects of astaxanthin and omega-3 on behavioral deficits and molecular changes in a prenatal valproic acid model of autism in rats

Objectives: Autism is a devastating neurodevelopmental disorder and recent studies showed that omega-3 or astaxanthin might reduce autistic symptoms due to their anti-inflammatory properties. Therefore, we investigated the effects of omega-3 and astaxanthin on the VPA-induced autism model of rats.Material and Methods: Female Wistar albino pups (n = 40) were grouped as control, autistic, astaxanthin (2 mg/kg), omega-3 (200 mg/kg), and astaxanthin (2 mg/kg)+omega-3 (200 mg/kg). All groups except the control were prenatally exposed to VPA. Astaxanthin and omega-3 were orally administered from the postnatal day 41 to 68 and behavioral tests were performed between day 69 and 73. The rats were decapitated 24 h after the behavioral tests and hippocampal and prefrontal cytokines and 5-HT levels were analyzed by ELISA.Results: VPA rats have increased grooming behavior while decreased sociability (SI), social preference index (SPI), discrimination index (DI), and prepulse inhibition (PPI) compared to control. Additionally, IL-1β, IL-6, TNF-α, and IFN-γ levels increased while IL-10 and 5-HT levels decreased in both brain regions. Astaxanthin treatment raised SI, SPI, DI, PPI, and prefrontal IL-10 levels. It also raised 5-HT levels and decreased IL-6 levels in both brain regions. Omega-3 and astaxanthin + omega-3 increased the SI, SPI, DI, and PPI and decreased grooming behavior. Moreover, they increased IL-10 and 5-HT levels whereas decreased IL-1β, IL-6, TNF-α, IFN-γ levels in both brain regions.Conclusions: Our results showed that VPA administration mimicked the behavioral and molecular changes of autism in rats. Single and combined administration of astaxanthin and omega-3 improved the autistic-like behavioral and molecular changes in the VPA model of rats.

The effects of astaxanthin supplementation on liver enzyme levels

According to previous studies, astaxanthin exerts various biological effects due to its anti-inflammatory and antioxidant capabilities; however, its effects on liver enzymes have not yet been well elucidated. Therefore, we conducted a meta-analysis to assess astaxanthin's effects on liver enzymes. A systematic literature search was conducted using scientific databases including PubMed, Scopus, Web of Science, the Cochrane databases, and Google Scholar up to February 2023 to find relevant randomized controlled trials (RCTs) examining the effects of astaxanthin supplementation on alanine transaminase (ALT), aspartate transaminase (AST), gamma-glutamyl transferase (GGT), and alkaline phosphatase (ALP). A random-effects model was used for the estimation of the pooled weighted mean difference (WMD). Overall, we included five trials involving 196 subjects. The duration of the intervention was between 4 and 48 weeks, and the dose was between 6 and 12 mg/day. ALT levels increased in the intervention group compared to the control group following astaxanthin supplementation (WMD: 1.92 U/L, 95% CI: 0.16 to 3.68, P=0.03), whereas supplementation with astaxanthin had a non-significant effect on AST (WMD: 0.72 U/L, 95% CI: -0.85 to 2.29, P=0.36), GGT (WMD: 0.48 U/L, 95% CI: -2.71 to 3.67, P=0.76), and ALP levels (WMD: 2.85 U/L, 95% CI: -7.94 to 13.63, P=0.60) compared to the placebo group. Our data showed that astaxanthin supplementation increases ALT concentrations in adults without affecting the levels of other liver enzymes. Further long-term and well-designed RCTs are necessary to assess and confirm these findings.

Therapeutic Potential of Natural Compounds in Subarachnoid Haemorrhage

Subarachnoid hemorrhage (SAH) is a common and fatal cerebrovascular disease with high morbidity, mortality and very poor prognosis worldwide. SAH can induce a complex series of pathophysiological processes, and the main factors affecting its prognosis are early brain injury (EBI) and delayed cerebral ischemia (DCI). The pathophysiological features of EBI mainly include intense neuroinflammation, oxidative stress, neuronal cell death, mitochondrial dysfunction and brain edema, while DCI is characterized by delayed onset ischemic neurological deficits and cerebral vasospasm (CVS). Despite much exploration in people to improve the prognostic outcome of SAH, effective treatment strategies are still lacking. In recent years, numerous studies have shown that natural compounds of plant origin have unique neuro- and vascular protective effects in EBI and DCI after SAH and long-term neurological deficits, which mainly include inhibition of inflammatory response, reduction of oxidative stress, anti-apoptosis, and improvement of blood-brain barrier and cerebral vasospasm. The aim of this paper is to systematically explore the processes of neuroinflammation, oxidative stress, and apoptosis in SAH, and to summarize natural compounds as potential targets for improving the prognosis of SAH and their related mechanisms of action for future therapies.

Pretreatment with Liposome-Encapsulated Shrimp Shell Extract Attenuated Neuronal Damage and Death in Aβ1-42-Induced Memory Deficits in Rats

The accumulation of amyloid-beta (Aβ) peptides is a crucial factor in the neuronal degeneration of Alzheimer's disease (AD). The current study investigated the underlying neuroprotective mechanisms of shrimp shell extract (SSE) and liposome-encapsulated SSE (SSE/L) against Aβ1-42-induced neuronal damage and death in rats. Intracerebroventricular infusion of Aβ1-42 effectively induced memory decline, as observed in a reduction of the rat's discriminating ability in the novel object recognition and novel object location tasks. Oral pretreatment with 100 mg/kg of SSE demonstrated no preventive effect on the memory decline induced by Aβ1-42 infusion. However, treatment with SSE/L 100 mg/kg BW effectively attenuated memory deficits in both behavioral assessments following two and four weeks after Aβ1-42 infusion. Moreover, SSE/L exerted neuroprotective effects by reducing lipid peroxidation and increasing Nrf2/HO-1 expression. There was a significant decrease in Iba1 and GFAP (biomarkers of microglia and astrocyte activity, respectively), as well as a decrease in the levels of NF-κB expression and the inflammatory cytokines TNF-α and IL-6 in the cortical and hippocampal tissues. Treatment with SSE/L also reduced the pro-apoptotic proteins Bax and cleaved caspase-3 while raising the anti-apoptotic protein Bcl2. In addition, the beneficial effects of SSE/L were along with the effects of a positive control commercial astaxanthin (AST). The findings of this study indicated that SSE/L provided neuroprotective effects on Aβ1-42-induced AD rats by ameliorating oxidative stress, neuroinflammation and apoptotic cell death. Therefore, SSE/L might be employed to prevent and mitigate Aβ accumulation-induced neurotoxicity in AD.

Astaxanthin Added during Post-Warm Recovery Mitigated Oxidative Stress in Bovine Vitrified Oocytes and Improved Quality of Resulting Blastocysts

Various antioxidants are tested to improve the viability and development of cryopreserved oocytes, due to their known positive health effects. The aim of this study was to find whether astaxanthin (AX), a xanthophyll carotenoid, could mitigate deteriorations that occurred during the vitrification/warming process in bovine oocytes. Astaxanthin (2.5 µM) was added to the maturation medium during the post-warm recovery period of vitrified oocytes for 3 h. Afterward, the oocytes were fertilized in vitro using frozen bull semen and presumptive zygotes were cultured in the B2 Menezo medium in a co-culture with BRL-1 cells at 38.5 °C and 5% CO2 until the blastocyst stage. AX addition significantly reduced ROS formation, lipid peroxidation, and lysosomal activity, while increasing mitochondrial activity in vitrified oocytes. Although the effect of AX on embryo development was not observed, it stimulated cell proliferation in the blastocysts derived from vitrified oocytes and improved their quality by upregulation or downregulation of some genes related to apoptosis (BCL2, CAS9), oxidative stress (GPX4, CDX2), and development (GJB5) compared to the vitrified group without AX. Therefore, the antioxidant properties of astaxanthin even during short exposure to bovine vitrified/warmed oocytes resulted in improved blastocyst quality comparable to those from fresh oocytes.

A review on the pharmacology, pharmacokinetics and toxicity of sophocarpine

Sophocarpine is a natural compound that belongs to the quinolizidine alkaloid family, and has a long history of use and widespread distribution in traditional Chinese herbal medicines such as Sophora alopecuroides L., Sophora flavescens Ait., and Sophora subprostrata. This article aims to summarize the pharmacology, pharmacokinetics, and toxicity of sophocarpine, evaluate its potential pharmacological effects in various diseases, and propose the necessity for further research and evaluation to promote its clinical application. A large number of studies have shown that it has anti-inflammatory, analgesic, antiviral, antiparasitic, anticancer, endocrine regulatory, and organ-protective effects as it modulates various signaling pathways, such as the NF-κB, MAPK, PI3K/AKT, and AMPK pathways. The distribution of sophocarpine in the body conforms to a two-compartment model, and sophocarpine can be detected in various tissues with a relatively short half-life. Although the pharmacological effects of sophocarpine have been confirmed, toxicity and safety assessments and reports on molecular mechanisms of its pharmacological actions have been limited. Given its significant pharmacological effects and potential clinical value, further research and evaluation are needed to promote the clinical application of sophocarpine.

Dietary Astaxanthin Can Promote the Growth and Motivate Lipid Metabolism by Improving Antioxidant Properties for Swimming Crab, Portunus trituberculatus

This study aimed to assess the influence of varying dietary levels of astaxanthin (AST) on the growth, antioxidant capacity and lipid metabolism of juvenile swimming crabs. Six diets were formulated to contain different AST levels, and the analyzed concentration of AST in experimental diets were 0, 24.2, 45.8, 72.4, 94.2 and 195.0 mg kg-1, respectively. Juvenile swimming crabs (initial weight 8.20 ± 0.01 g) were fed these experimental diets for 56 days. The findings indicated that the color of the live crab shells and the cooked crab shells gradually became red with the increase of dietary AST levels. Dietary 24.2 mg kg-1 astaxanthin significantly improved the growth performance of swimming crab. the lowest activities of glutathione (GSH), total antioxidant capacity (T-AOC), superoxide dismutase (SOD) and peroxidase (POD) were found in crabs fed without AST supplementation diet. Crabs fed diet without AST supplementation showed lower lipid content and the activity of fatty acid synthetase (FAS) in hepatopancreas than those fed diets with AST supplementation, however, lipid content in muscle and the activity of carnitine palmitoyl transferase (CPT) in hepatopancreas were not significantly affected by dietary AST levels. And it can be found in oil red O staining that dietary 24.2 and 45.8 mg kg-1 astaxanthin significantly promoted the lipid accumulation of hepatopancreas. Crabs fed diet with 195.0 mg kg-1 AST exhibited lower expression of ampk, foxo, pi3k, akt and nadph in hepatopancreas than those fed the other diets, however, the expression of genes related to antioxidant such as cMn-sod, gsh-px, cat, trx and gst in hepatopancreas significantly down-regulated with the increase of dietary AST levels. In conclusion, dietary 24.2 and 45.8 mg kg-1 astaxanthin significantly promoted the lipid accumulation of hepatopancreas and im-proved the antioxidant and immune capacity of hemolymph.

Astaxanthin attenuates cigarette smoke-induced small airway remodeling via the AKT1 signaling pathway

BACKGROUND

Astaxanthin (AXT) is a keto-carotenoid with a variety of biological functions, including antioxidant and antifibrotic effects. Small airway remodeling is the main pathology of chronic obstructive pulmonary disease (COPD) and is caused by epithelial-to-mesenchymal transition (EMT) and fibroblast differentiation and proliferation. Effective therapies are still lacking. This study aimed to investigate the role of AXT in small airway remodeling in COPD and its underlying mechanisms.

METHODS

First, the model of COPD mice was established by cigarette smoke (CS) exposure combined with intraperitoneal injection of cigarette smoke extract (CSE). The effects of AXT on the morphology of CS combined with CSE -induced emphysema, EMT, and small airway remodeling by using Hematoxylin-eosin (H&E) staining, immunohistochemical staining, and western blot. In addition, in vitro experiments, the effects of AXT on CSE induced-EMT and fibroblast function were further explored. Next, to explore the specific mechanisms underlying the protective effects of AXT in COPD, potential targets of AXT in COPD were analyzed using network pharmacology. Finally, the possible mechanism was verified through molecular docking and in vitro experiments.

RESULTS

AXT alleviated pulmonary emphysema, EMT, and small airway remodeling in a CS combined with CSE -induced mouse model. In addition, AXT inhibited the EMT process in airway cells and the differentiation and proliferation of fibroblasts. Mechanistically, AXT inhibited myofibroblast activation by directly binding to and suppressing the phosphorylation of AKT1. Therefore, our results show that AXT protects against small airway remodeling by inhibiting AKT1.

CONCLUSIONS

The present study identified and illustrated a new food function of AXT, indicating that AXT could be used in the therapy of COPD-induced small airway remodeling.

Reprogramming Macrophage Polarization, Depleting ROS by Astaxanthin and Thioketal-Containing Polymers Delivering Rapamycin for Osteoarthritis Treatment

Osteoarthritis (OA) is a chronic joint disease characterized by synovitis and joint cartilage destruction. The severity of OA is highly associated with the imbalance between M1 and M2 synovial macrophages. In this study, a novel strategy is designed to modulate macrophage polarization by reducing intracellular reactive oxygen species (ROS) levels and regulating mitochondrial function. A ROS-responsive polymer is synthesized to self-assemble with astaxanthin and autophagy activator rapamycin to form nanoparticles (NP@PolyRHAPM ). In vitro experiments show that NP@PolyRHAPM significantly reduced intracellular ROS levels. Furthermore, NP@PolyRHAPM restored mitochondrial membrane potential, increased glutathione (GSH) levels, and promoted intracellular autophagy, hence successfully repolarizing M1 macrophages into the M2 phenotype. This repolarization enhanced chondrocyte proliferation and vitality while inhibiting apoptosis. In vivo experiments utilizing an anterior cruciate ligament transection (ACLT)-induced OA mouse model revealed the anti-inflammatory and cartilage-protective effects of NP@PolyRHAPM , effectively mitigating OA progression. Consequently, the findings suggest that intra-articular delivery of ROS-responsive nanocarrier systems holds significant promise as a potential and effective therapeutic strategy for OA treatment.

The Biosynthesis of Astaxanthin Esters in Schizochytrium sp. is Mediated by a Bifunctional Diacylglycerol Acyltransferase

Astaxanthin esters are a major form of astaxanthin found in nature. However, the exact mechanisms of the biosynthesis and storage of astaxanthin esters were previously unknown. We found that Schizochytrium sp. synthesized both astaxanthin and docosahexaenoic acid (DHA)-enriched lipids. The major type of astaxanthin produced was free astaxanthin along with astaxanthin-DHA monoester and other esterified forms. DHA accounted for 41.0% of the total fatty acids from astaxanthin monoesters. These compounds were deposited mainly in lipid droplets. The biosynthesis of the astaxanthin esters was mainly carried out by a novel diacylglycerol acyltransferase ScDGAT2-1, while ScDGAT2-2 was involved only in the production of triacylglycerol. We also identified astaxanthin ester synthases from the astaxanthin-producing algae Haematococcus pluvialis and Chromochloris zofingiensis, as well as a thraustochytrid Hondaea fermentalgiana with an unknown carotenoid profile. This investigation enlightens the application of thraustochytrids for the production of both DHA and astaxanthin and provides enzyme resources for the biosynthesis of astaxanthin esters in the engineered microbes.

Protective Effects of Astaxanthin on Ochratoxin A-Induced Liver Injury: Effects of Endoplasmic Reticulum Stress and Mitochondrial Fission-Fusion Balance

Ochratoxin A (OTA), a common mycotoxin, can contaminate food and feed and is difficult to remove. Astaxanthin (ASTA), a natural antioxidant, can effectively protect against OTA-induced hepatotoxicity; however, its mechanism of action remains unclear. In the present study, we elucidate the protective effects of ASTA on the OTA-induced damage of the endoplasmic reticulum and mitochondria in broiler liver samples by serum biochemical analysis, antioxidant analysis, qRT-PCR, and Western blot analysis. ASTA inhibited the expressions of ahr, pxr, car, cyp1a1, cyp1a5, cyp2c18, cyp2d6, and cyp3a9 genes, and significantly alleviated OTA-induced liver oxidative damage (SOD, GSH-Px, GSH, MDA). Furthermore, it inhibited OTA-activated endoplasmic reticulum stress genes and proteins (grp94, GRP78, atf4, ATF6, perk, eif2α, ire1, CHOP). ASTA alleviated OTA-induced mitochondrial dynamic imbalance, inhibited mitochondrial division (DRP1, mff), and promoted mitochondrial fusion (OPA1, MFN1, MFN2). In conclusion, ASTA can decrease OTA-induced oxidative damage, thereby alleviating endoplasmic reticulum stress and mitochondrial dynamic imbalance.

Astaxanthin from microalgae: A review on structure, biosynthesis, production strategies and application

Astaxanthin is a red-colored secondary metabolite with excellent antioxidant properties, typically finds application as foods, feed, cosmetics, nutraceuticals, and medications. Astaxanthin is usually produced synthetically using chemicals and costs less as compared to the natural astaxanthin obtained from fish, shrimps, and microorganisms. Over the decades, astaxanthin has been naturally synthesized from Haematococcus pluvialis in commercial scales and remains exceptional, attributed to its higher bioactive properties as compared to synthetic astaxanthin. However, the production cost of algal astaxanthin is still high due to several bottlenecks prevailing in the upstream and downstream processes. To that end, the present study intends to review the recent trends and advancements in astaxanthin production from microalgae. The structure of astaxanthin, sources, production strategies of microalgal astaxanthin, and factors influencing the synthesis of microalgal astaxanthin were discussed while detailing the pathway involved in astaxanthin biosynthesis. The study also discusses the relevant downstream process used in commercial scales and details the applications of astaxanthin in various health related issues.

Neddylation Regulation of Immune Responses

Neddylation plays a vital role in post-translational modification, intricately shaping the regulation of diverse biological processes, including those related to cellular immune responses. In fact, neddylation exerts control over both innate and adaptive immune systems via various mechanisms. Specifically, neddylation influences the function and survival of innate immune cells, activation of pattern recognition receptors and GMP-AMP synthase-stimulator of interferon genes pathways, as well as the release of various cytokines in innate immune reactions. Moreover, neddylation also governs the function and survival of antigen-presenting cells, which are crucial for initiating adaptive immune reactions. In addition, neddylation regulates T cell activation, proliferation, differentiation, survival, and their effector functions, thereby ensuring an appropriate adaptive immune response. In this review, we summarize the most recent findings in these aspects and delve into the connection between dysregulated neddylation events and immunological disorders, especially inflammatory diseases. Lastly, we propose future directions and potential treatments for these diseases by targeting neddylation.

Recent advances in anti-inflammatory active components and action mechanisms of natural medicines

Inflammation is a series of reactions caused by the body's resistance to external biological stimuli. Inflammation affects the occurrence and development of many diseases. Anti-inflammatory drugs have been used widely to treat inflammatory diseases, but long-term use can cause toxic side-effects and affect human functions. As immunomodulators with long-term conditioning effects and no drug residues, natural products are being investigated increasingly for the treatment of inflammatory diseases. In this review, we focus on the inflammatory process and cellular mechanisms in the development of diseases such as inflammatory bowel disease, atherosclerosis, and coronavirus disease-2019. Also, we focus on three signaling pathways (Nuclear factor-kappa B, p38 mitogen-activated protein kinase, Janus kinase/signal transducer and activator of transcription-3) to explain the anti-inflammatory effect of natural products. In addition, we also classified common natural products based on secondary metabolites and explained the association between current bidirectional prediction progress of natural product targets and inflammatory diseases.

Astaxanthin alleviates PM2.5-induced cardiomyocyte injury via inhibiting ferroptosis

BACKGROUND

Long-term exposure of humans to air pollution is associated with an increasing risk of cardiovascular diseases (CVDs). Astaxanthin (AST), a naturally occurring red carotenoid pigment, was proved to have multiple health benefits. However, whether or not AST also exerts a protective effect on fine particulate matter (PM2.5)-induced cardiomyocyte damage and its underlying mechanisms remain unclear.

METHODS

In vitro experiments, the H9C2 cells were subjected to pretreatment with varying concentrations of AST, and then cardiomyocyte injury model induced by PM2.5 was established. The cell viability and the ferroptosis-related proteins expression were measured in different groups. In vivo experiments, the rats were pretreated with different concentrations of AST for 21 days. Subsequently, a rat model of myocardial PM2.5 injury was established by intratracheal instillation every other day for 1 week. The effects of AST on myocardial tissue injury caused by PM2.5 indicating by histological, serum, and protein analyses were examined.

RESULTS

AST significantly ameliorated PM2.5-induced myocardial tissue injury, inflammatory cell infiltration, the release of inflammatory factors, and cardiomyocyte H9C2 cell damage. Mechanistically, AST pretreatment increased the expression of SLC7A11, GPX4 and down-regulated the expression of TfR1, FTL and FTH1 in vitro and in vivo.

CONCLUSIONS

Our study suggest that ferroptosis plays a significant role in the pathogenesis of cardiomyocyte injury induced by PM2.5. AST may serve as a potential therapeutic agent for mitigating cardiomyocyte injury caused by PM2.5 through the inhibition of ferroptosis.

Advances in Neuropathic Pain Research: Selected Intracellular Factors as Potential Targets for Multidirectional Analgesics

Neuropathic pain is a complex and debilitating condition that affects millions of people worldwide. Unlike acute pain, which is short-term and starts suddenly in response to an injury, neuropathic pain arises from somatosensory nervous system damage or disease, is usually chronic, and makes every day functioning difficult, substantially reducing quality of life. The main reason for the lack of effective pharmacotherapies for neuropathic pain is its diverse etiology and the complex, still poorly understood, pathophysiological mechanism of its progression. Numerous experimental studies, including ours, conducted over the last several decades have shown that the development of neuropathic pain is based on disturbances in cell activity, imbalances in the production of pronociceptive factors, and changes in signaling pathways such as p38MAPK, ERK, JNK, NF-κB, PI3K, and NRF2, which could become important targets for pharmacotherapy in the future. Despite the availability of many different analgesics, relieving neuropathic pain is still extremely difficult and requires a multidirectional, individual approach. We would like to point out that an increasing amount of data indicates that nonselective compounds directed at more than one molecular target exert promising analgesic effects. In our review, we characterize four substances (minocycline, astaxanthin, fisetin, and peimine) with analgesic properties that result from a wide spectrum of actions, including the modulation of MAPKs and other factors. We would like to draw attention to these selected substances since, in preclinical studies, they show suitable analgesic properties in models of neuropathy of various etiologies, and, importantly, some are already used as dietary supplements; for example, astaxanthin and fisetin protect against oxidative stress and have anti-inflammatory properties. It is worth emphasizing that the results of behavioral tests also indicate their usefulness when combined with opioids, the effectiveness of which decreases when neuropathy develops. Moreover, these substances appear to have additional, beneficial properties for the treatment of diseases that frequently co-occur with neuropathic pain. Therefore, these substances provide hope for the development of modern pharmacological tools to not only treat symptoms but also restore the proper functioning of the human body.

Effects of oxidative stress regulation in inflammation-associated gastric cancer progression treated using traditional Chinese medicines: A review

Gastric cancer (GC) is a global public health concern that poses a serious threat to human health owing to its high morbidity and mortality rates. Due to the lack of specificity of symptoms, patients with GC tend to be diagnosed at an advanced stage with poor prognosis. Therefore, the development of new treatment methods is particularly urgent. Chronic atrophic gastritis (CAG), a precancerous GC lesion, plays a key role in its occurrence and development. Oxidative stress has been identified as an important factor driving the development and progression of the pathological processes of CAG and GC. Therefore, regulating oxidative stress pathways can not only intervene in CAG development but also prevent the occurrence and metastasis of GC and improve the prognosis of GC patients. In this study, PubMed, CNKI, and Web of Science were used to search for a large number of relevant studies. The review results suggested that the active ingredients of traditional Chinese medicine (TCM) and TCM prescriptions could target and improve inflammation, pathological status, metastasis, and invasion of tumor cells, providing a potential new supplement for the treatment of CAG and GC.

Modification of titanium orthopedic implants with bioactive glass: a systematic review of in vivo and in vitro studies

Bioactive glasses (BGs) are ideal biomaterials in the field of bio-restoration due to their excellent biocompatibility. Titanium alloys are widely used as a bone graft substitute material because of their excellent corrosion resistance and mechanical properties; however, their biological inertness makes them prone to clinical failure. Surface modification of titanium alloys with bioactive glass can effectively combine the superior mechanical properties of the substrate with the biological properties of the coating material. In this review, the relevant articles published from 2013 to the present were searched in four databases, namely, Web of Science, PubMed, Embase, and Scopus, and after screening, 49 studies were included. We systematically reviewed the basic information and the study types of the included studies, which comprise in vitro experiments, animal tests, and clinical trials. In addition, we summarized the applied coating technologies, which include pulsed laser deposition (PLD), electrophoretic deposition, dip coating, and magnetron sputtering deposition. The superior biocompatibility of the materials in terms of cytotoxicity, cell activity, hemocompatibility, anti-inflammatory properties, bioactivity, and their good bioactivity in terms of osseointegration, osteogenesis, angiogenesis, and soft tissue adhesion are discussed. We also analyzed the advantages of the existing materials and the prospects for further research. Even though the current research status is not extensive enough, it is still believed that BG-coated Ti implants have great clinical application prospects.

Extraction and Purification of Highly Active Astaxanthin from Corynebacterium glutamicum Fermentation Broth

The marine carotenoid astaxanthin is one of the strongest natural antioxidants and therefore is used in a broad range of applications such as cosmetics or nutraceuticals. To meet the growing market demand, the natural carotenoid producer Corynebacterium glutamicum has been engineered to produce astaxanthin by heterologous expression of genes from the marine bacterium Fulvimarina pelagi. To exploit this promising source of fermentative and natural astaxanthin, an efficient extraction process using ethanol was established in this study. Appropriate parameters for ethanol extraction were identified by screening ethanol concentration (62.5-97.5% v/v), temperature (30-70 °C) and biomass-to-solvent ratio (3.8-19.0 mgCDW/mLsolvent). The results demonstrated that the optimal extraction conditions were: 90% ethanol, 60 °C, and a biomass-to-solvent ratio of 5.6 mgCDW/mLsolvent. In total, 94% of the cellular astaxanthin was recovered and the oleoresin obtained contained 9.4 mg/g astaxanthin. With respect to other carotenoids, further purification of the oleoresin by column chromatography resulted in pure astaxanthin (100%, HPLC). In addition, a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay showed similar activities compared to esterified astaxanthin from microalgae and a nine-fold higher antioxidative activity than synthetic astaxanthin.

Anti-Osteoarthritic Effects of Antarctic Krill Oil in Primary Chondrocytes and a Surgical Rat Model of Knee Osteoarthritis

Osteoarthritis (OA) is characterized by progressive cartilage destruction and synovitis; however, there are no approved disease-modifying OA drugs. Krill oil (KO) has been reported to possess anti-inflammatory properties and alleviate joint pain in knee OA, indicating its potential to target the inflammatory mechanism of OA. Therefore, the anti-OA effects of KO were investigated in primary chondrocytes and a surgical rat model of knee OA. The oral administration of KO at 200 and 100 mg/kg for 8 weeks improved joint swelling and mobility in the animal model and led to increased bone mineral density and compressive strength in the cartilage. The oral KO doses upregulated chondrogenic genes (type 2 collagen, aggrecan, and Sox9), with inhibition of inflammation markers (5-lipoxygenase and prostaglandin E2) and extracellular matrix (ECM)-degrading enzymes (MMP-2 and MMP-9) in the cartilage and synovium. Consistently, KO treatments increased the viability of chondrocytes exposed to interleukin 1α, accompanied by the upregulation of the chondrogenic genes and the inhibition of the ECM-degrading enzymes. Furthermore, KO demonstrated inhibitory effects on lipopolysaccharide-induced chondrocyte inflammation. Histopathological and immunohistochemical analyses revealed that KO improved joint destruction and synovial inflammation, probably due to the anti-inflammatory, anti-apoptotic, and chondrogenic effects. These findings suggest the therapeutic potential of KO for knee OA.

Carotenoids from Starfish Patiria pectinifera: Therapeutic Activity in Models of Inflammatory Diseases

The carotenoids mixture (MC) isolated from the starfish Patiria. pectinifera contains more than 50% astaxanthin, 4-6% each zeaxanthine and lutein, and less pharmacologically active components such as free fatty acids and their glycerides. Astaxanthin, the major component of MC, belongs to the xanthophyll class of carotenoids, and is well known for its antioxidant properties. In this work, in vitro and in vivo studies on the biological activity of MC were carried out. The complex was shown to exhibit anti-inflammatory, anti-allergic and cancer-preventive activity, without any toxicity at a dose of 500 mg/kg. MC effectively improves the clinical picture of the disease progressing, as well as normalizing the cytokine profile and the antioxidant defense system in the in vivo animal models of inflammatory diseases, namely: skin carcinogenesis, allergic contact dermatitis (ACD) and systemic inflammation (SI). In the skin carcinogenesis induced by 7,12-dimethylbenzanthracene, the incidence of papillomas was decreased 1.5 times; 1% MC ointment form in allergic contact dermatitis showed an 80% reduced severity of pathomorphological skin manifestations. Obtained results show that MC from starfish P. pectinifera is an effective remedy for the treatment and prevention of inflammatory processes.

Effects of Extracts of Two Selected Strains of Haematococcus pluvialis on Adipocyte Function

Recently, microalgae are arousing considerable interest as a source of countless molecules with potential impacts in the nutraceutical and pharmaceutical fields. Haematococcus pluvialis, also named Haematococcus lacustris, is the largest producer of astaxanthin, a carotenoid exhibiting powerful health effects, including anti-lipogenic and anti-diabetic activities. This study was carried out to investigate the properties of two selected strains of H. pluvialis (FBR1 and FBR2) on lipid metabolism, lipolysis and adipogenesis using an in vitro obesity model. FBR1 and FBR2 showed no antiproliferative effect at the lowest concentration in 3T3-L1 adipocytes. Treatment with FBR2 extract reduced lipid deposition, detected via Oil Red O staining and the immunocontent of the adipogenic proteins PPARγ, ACLY and AMPK was revealed using Western blot analysis. Extracts from both strains induced lipolysis in vitro and reduced the secretion of interleukin-6 and tumor necrosis factor-α. Moreover, the FBR1 and FBR2 extracts improved mitochondrial function, reducing the levels of mitochondrial superoxide anion radical and increasing mitochondrial mass compared to untreated adipocytes. These findings suggest that FBR2 extract, more so than FBR1, may represent a promising strategy in overweight and obesity prevention and treatment.

Progress on the Extraction, Separation, Biological Activity, and Delivery of Natural Plant Pigments

Natural plant pigments are safe and have low toxicity, with various nutrients and biological activities. However, the extraction, preservation, and application of pigments are limited due to the instability of natural pigments. Therefore, it is necessary to examine the extraction and application processes of natural plant pigments in detail. This review discusses the classification, extraction methods, biological activities, and modification methods that could improve the stability of various pigments from plants, providing a reference for applying natural plant pigments in the industry and the cosmetics, food, and pharmaceutical industries.

Micro-algal astaxanthin improves lambda-cyhalothrin-induced necroptosis and inflammatory responses via the ROS-mediated NF-κB signaling in lymphocytes of carp (Cyprinus carpio L.)

Lambda-cyhalothrin (LCY) is a widely used toxic pesticide that causes harmful effects on the immune organs of fish and aquatic species. Micro-algal astaxanthin (MAA), a heme pigment found in haematococcus pluvialis, has been shown to benefit antioxidants and immunity in aquaculture. To investigate how MAA protects carp lymphocytes from LCY-induced immunotoxicity, a model of fish lymphocytes treated with LCY and/or MAA was established. Lymphocytes from carp (Cyprinus carpio L.) were given LCY (80 μM) and/or MAA (50 μM) as a treatment for a period of 24 h. Firstly, LCY exposure resulted in excessive ROS and malondialdehyde production and reduces antioxidant enzymes (SOD and CAT), indicating a reduced capacity of the antioxidant system. Secondly, the results of flow cytometry and AO/EB labeling proved that lymphocytes treated with LCY have a larger ratio of necroptosis. In addition, LCY upregulated the levels of necroptosis-related regulatory factors (RIP1, RIP3 and MLKL) via the ROS-mediated NF-κB signaling pathway in lymphocytes. Thirdly, LCY treatment caused increased secretion of inflammatory genes (IL-6, INF-γ, IL-4, IL-1β and TNF-α), leading to immune dysfunction in lymphocytes. Surprisingly, LCY-induced immunotoxicity was inhibited by MAA treatment, indicating that it effectively attenuated the LCY-induced changes described above. Overall, we concluded that MAA treatment could ameliorate LCY-induced necroptosis and immune dysfunction by inhibiting the ROS-mediated NF-κB signaling in lymphocytes. It provides insights into the protection of farmed fish from agrobiological threats in fish under LCY and the value of MAA applications in aquaculture.

Astaxanthin prevents osteoarthritis by blocking Rspo2-mediated Wnt/β-catenin signaling in chondrocytes and abolishing Rspo2-related inflammatory factors in macrophages

Chondrocyte degeneration and classically activated macrophage (AM)-related inflammation play critical roles in osteoarthritis (OA). Here, we explored the effects of astaxanthin and Rspo2 on OA in vitro and in vivo. We observed that the Rspo2 gene was markedly elevated in synovial tissues of OA patients compared with healthy controls. In 2D cultures, Rspo2 and inflammatory factors were enhanced in AMs compared with nonactivated macrophages (NMs), and the protein expression levels of Rspo2, β-catenin, and inflammatory factors were increased, and anabolic markers were reduced in osteoarthritic chondrocytes (OACs) compared to normal chondrocytes (NCs). Astaxanthin reversed these changes in AMs and OACs. Furthermore, Rspo2 shRNA significantly abolished inflammatory factors and elevated anabolic markers in OACs. In NCs cocultured with AM, and in OACs cocultured with AMs or NMs, astaxanthin reversed these changes in these coculture systems and promoted secretion of Rspo2, β-catenin and inflammatory factors and suppressed anabolic markers compared to NCs or OACs cultured alone. In AMs, coculture with NCs resulted in a slight elevation of Rspo2 and AM-related genes, but not protein expression, compared to culture alone, but when cocultured with OACs, these inflammatory mediators were significantly enhanced at both the gene and protein levels. Astaxanthin reversed these changes in all the groups. In vivo, we observed a deterioration in cartilage quality after intra-articular injection of Rspo2 associated with medial meniscus (DMM)-induced instability in the OA group, and astaxanthin was protective in these groups. Our results collectively revealed that astaxanthin attenuated the process of OA by abolishing Rspo2 both in vitro and in vivo.

Microbial astaxanthin: from bioprocessing to the market recognition

The attractive biological properties and health benefits of natural astaxanthin (AXT), including its antioxidant and anti-carcinogenic properties, have garnered significant attention from academia and industry seeking natural alternatives to synthetic products. AXT, a red ketocarotenoid, is mainly produced by yeast, microalgae, wild or genetically engineered bacteria. Unfortunately, the large fraction of AXT available in the global market is still obtained using non-environmentally friendly petrochemical-based products. Due to the consumers concerns about synthetic AXT, the market of microbial-AXT is expected to grow exponentially in succeeding years. This review provides a detailed discussion of AXT's bioprocessing technologies and applications as a natural alternative to synthetic counterparts. Additionally, we present, for the first time, a very comprehensive segmentation of the global AXT market and suggest research directions to improve microbial production using sustainable and environmentally friendly practices. KEY POINTS: • Unlock the power of microorganisms for high value AXT production. • Discover the secrets to cost-effective microbial AXT processing. • Uncover the future opportunities in the AXT market.

Production and therapeutic use of astaxanthin in the nanotechnology era

Astaxanthin (AXT) is a red fat-soluble pigment found naturally in aquatic animals, plants, and various microorganisms and can be manufactured artificially using chemical catalysis. AXT is a xanthophyll carotenoid with a high potential for scavenging free radicals. Several studies have investigated AXT efficacy against diseases such as neurodegenerative, ocular, skin, and cardiovascular hypertension, diabetes, gastrointestinal and liver diseases, and immuno-protective functions. However, its poor solubility, low stability to light and oxygen, and limited bioavailability are major obstacles hindering its wide applications as a therapeutic agent or nutritional supplement. Incorporating AXT with nanocarriers holds great promise in enhancing its physiochemical properties. Nanocarriers are delivery systems with several benefits, including surface modification, bioactivity, and targeted medication delivery and release. Many approaches have been applied to enhance AXT's medicinal effect, including solid lipid nanoparticles, nanostructured lipid carriers (NLCs) and polymeric nanospheres. AXT nano-formulations have demonstrated a high antioxidant and anti-inflammatory effect, significantly affecting cancer in different organs. This review summarizes the most recent data on AXT production, characterization, biological activity, and therapeutic usage, focusing on its uses in the nanotechnology era.

Astaxanthin suppresses oxidative stress and calcification in vertebral cartilage endplate via activating Nrf-2/HO-1 signaling pathway

BACKGROUND

Cartilage endplate (CEP) degeneration is an important initiating factor leading to intervertebral disc degeneration (IVDD). Astaxanthin (Ast) is a natural lipid-soluble and red-orange carotenoid which possesses various biological activities, including antioxidant, anti-inflammatory, and anti-aging effects in multiple organisms. However, the effects and mechanism of Ast on endplate chondrocytes remain largely unknown. The objective of the current study was to investigate the effects and of Ast on CEP degeneration and its underlying molecular mechanisms.

METHODS

Tert-butyl hydroperoxide (TBHP) was used to mimic the IVDD pathological environment. We investigated the effects of Ast on the Nrf2 signaling pathway and damage-associated events. The IVDD model was constructed by surgical resection of L4 posterior elements to explore the role of Ast in vivo.

RESULTS

We found that the activation of the Nrf-2/HO-1 signaling pathway was enhanced by Ast, thus promoted mitophagy process, inhibited oxidative stress and CEP chondrocytes ferroptosis, eventually ameliorated extracellular matrix (ECM) degradation, CEP calcification and endplate chondrocytes apoptosis. Knockdown of Nrf-2 using siRNA inhibited Ast induced mitophagy process and its protective effect. Moreover, Ast inhibited oxidative stimulation-induced NF-κB activity and could ameliorate the inflammation response. The results also were confirmed by experiments in vivo, Ast alleviated IVDD development and CEP calcification.

CONCLUSIONS

Ast could protect vertebral cartilage endplate against oxidative stress and degeneration via activating Nrf-2/HO-1 pathway. Our results imply that Ast may serve as a potential therapeutic agent for IVDD progression and treatment.

Skeletonema marinoi Extracts and Associated Carotenoid Fucoxanthin Downregulate Pro-Angiogenic Mediators on Prostate Cancer and Endothelial Cells

The exploration of natural preventive molecules for nutraceutical and pharmaceutical use has recently increased. In this scenario, marine microorganisms represent an underestimated source of bioactive products endowed with beneficial effects on health that include anti-oxidant, anti-inflammatory, differentiating, anti-tumor, and anti-angiogenic activities. Here, we tested the potential chemopreventive and anti-angiogenic activities of an extract from the marine coastal diatom Skeletonema marinoi Sarno and Zingone (Sm) on prostate cancer (PCa) and endothelial cells. We also tested one of the main carotenoids of the diatom, the xanthophyll pigment fucoxanthin (Fuco). Fuco from the literature is a potential candidate compound involved in chemopreventive activities. Sm extract and Fuco were able to inhibit PCa cell growth and hinder vascular network formation of endothelial cells. The reduced number of cells was partially due to growth inhibition and apoptosis. We studied the molecular targets by qPCR and membrane antibody arrays. Angiogenesis and inflammation molecules were modulated. In particular, Fuco downregulated the expression of Angiopoietin 2, CXCL5, TGFβ, IL6, STAT3, MMP1, TIMP1 and TIMP2 in both prostate and endothelial cells. Our study confirmed microalgae-derived drugs as potentially relevant sources of novel nutraceuticals, providing candidates for potential dietary or dietary supplement intervention in cancer prevention approaches.

Astaxanthin as a King of Ketocarotenoids: Structure, Synthesis, Accumulation, Bioavailability and Antioxidant Properties

Astaxanthin (3,3-dihydroxy-β, β-carotene-4,4-dione) is a ketocarotenoid synthesized by Haematococcus pluvialis/lacustris, Chromochloris zofingiensis, Chlorococcum, Bracteacoccus aggregatus, Coelastrella rubescence, Phaffia rhodozyma, some bacteria (Paracoccus carotinifaciens), yeasts, and lobsters, among others However, it is majorly synthesized by Haematococcus lacustris alone (about 4%). The richness of natural astaxanthin over synthetic astaxanthin has drawn the attention of industrialists to cultivate and extract it via two stage cultivation process. However, the cultivation in photobioreactors is expensive, and converting it in soluble form so that it can be easily assimilated by our digestive system requires downstream processing techniques which are not cost-effective. This has made the cost of astaxanthin expensive, prompting pharmaceutical and nutraceutical companies to switch over to synthetic astaxanthin. This review discusses the chemical character of astaxanthin, more inexpensive cultivating techniques, and its bioavailability. Additionally, the antioxidant character of this microalgal product against many diseases is discussed, which can make this natural compound an excellent drug to minimize inflammation and its consequences.

Research progress of Astaxanthin nano-based drug delivery system: Applications, prospects and challenges?

Astaxanthin (ASX) is a kind of carotenoid widely distributed in nature, which has been shown to extremely strong antioxidative effects and significant preventive and therapeutic effects on cancer, diabetes, cardiovascular disease, etc. However, its application in the medical field is greatly limited due to its poor water solubility, unstable chemical properties and other shortcomings. In recent years, the nano-based drug delivery systems such as nanoparticles, liposomes, nanoemulsions, nanodispersions, and polymer micelles, have been used as Astaxanthin delivery carriers with great potential for clinical applications, which have been proved that they can enhance the stability and efficacy of Astaxanthin and achieve targeted delivery of Astaxanthin. Herein, based on the pharmacological effects of Astaxanthin, we reviewed the characteristics of various drug delivery carriers, which is of great significance for improving the bioavailability of Astaxanthin.

Recent Advancements and Biotechnological Implications of Carotenoid Metabolism of Brassica

Carotenoids were synthesized in the plant cells involved in photosynthesis and photo-protection. In humans, carotenoids are essential as dietary antioxidants and vitamin A precursors. Brassica crops are the major sources of nutritionally important dietary carotenoids. Recent studies have unraveled the major genetic components in the carotenoid metabolic pathway in Brassica, including the identification of key factors that directly participate or regulate carotenoid biosynthesis. However, recent genetic advances and the complexity of the mechanism and regulation of Brassica carotenoid accumulation have not been reviewed. Herein, we reviewed the recent progress regarding Brassica carotenoids from the perspective of forward genetics, discussed biotechnological implications and provided new perspectives on how to transfer the knowledge of carotenoid research in Brassica to the crop breeding process.

Astaxanthin attenuates cigarette smoking-induced oxidative stress and inflammation in a sirtuin 1-dependent manner

Oxidative stress and chronic inflammation play key roles in the pathogenesis of chronic obstructive pulmonary disease (COPD). Astaxanthin (AXT) is a keto-carotenoid with a variety of biological functions, including antioxidant and anti-inflammatory effects This study aimed to explore the protective role and underlying mechanism of AXT in the pathogenesis of COPD. In this study, we found AXT alleviated pulmonary emphysema in a CS-exposed mouse model and regulated the expression of MMP-9/TIMP-1. And, AXT attenuates CSE-induced small airway fibrosis. Meanwhile, AXT inhibited Nrf2-modulated oxidative stress and the p65 NF-κB-regulated inflammatory pathway in both the mouse model and CSE-treated HBE cells. Mechanistically, AXT could directly bind to SIRT1 (the binding energy of the complex was -8.8 kcal/mol) and regulate the deacetylation activity of SIRT1. Finally, by activating SIRT1 deacetylation, AXT deacetylated Nrf2 and contributed to its action of reducing oxidative stress by generating antioxidant enzymes, and inhibiting p65 NF-κB transcriptional activity to suppress the inflammatory response. Our results show that treatment with AXT significantly reverses the oxidative stress and inflammation induced by cigarette smoke both in vivo and in vitro in a sirtuin 1-dependent manner.

Pangenome analysis of the genus Herbiconiux and proposal of four new species associated with Chinese medicinal plants

Five Gram-stain-positive, aerobic, non-motile actinobacterial strains designated as CPCC 205763T, CPCC 203386T, CPCC 205716T, CPCC 203406T, and CPCC 203407 were obtained from different ecosystems associated with four kinds of Chinese traditional medicinal plants. The 16S rRNA gene sequences of these five strains showed closely related to members of the genus Herbiconiux of the family Microbacteriaceae, with the highest similarities of 97.4-99.7% to the four validly named species of Herbiconiux. In the phylogenetic trees based on 16S rRNA gene sequences and the core genome, these isolates clustered into the clade of the genus Herbiconiux within the lineage of the family Microbacteriaceae. The overall genome relatedness indexes (values of ANI and dDDH) and the phenotypic properties (morphological, physiological and chemotaxonomic characteristics) of these isolates, readily supported to affiliate them to the genus Herbiconiux, representing four novel species, with the isolates CPCC 203406T and CPCC 203407 being classified in the same species. For which the names Herbiconiux aconitum sp. nov. (type strain CPCC 205763T = I19A-01430T = CGMCC 1.60067T), Herbiconiux daphne sp. nov. (type strain CPCC 203386T = I10A-01569T = DSM 24546T = KCTC 19839T), Herbiconiux gentiana sp. nov. (type strain CPCC 205716T = I21A-01427T = CGMCC 1.60064T), and Herbiconiux oxytropis sp. nov. (type strain CPCC 203406T = I10A-02268T = DSM 24549T = KCTC 19840T) were proposed, respectively. In the genomes of these five strains, the putative encoding genes for amidase, endoglucanase, phosphatase, and superoxidative dismutase were retrieved, which were classified as biosynthetic genes/gene-clusters regarding plant growth-promotion (PGP) functions. The positive results from IAA-producing, cellulose-degrading and anti-oxidation experiments further approved their potential PGP bio-functions. Pangenome analysis of the genus Herbiconiux supported the polyphasic taxonomy results and confirmed their bio-function potential.

Extraction of Valuable Biomolecules from the Microalga Haematococcus pluvialis Assisted by Electrotechnologies

The freshwater microalga Haematococcus pluvialis is well known as the cell factory for natural astaxanthin, which composes up to 4-7% of its total dry weight. The bioaccumulation of astaxanthin in H. pluvialis cysts seems to be a very complex process that depends on different stress conditions during its cultivation. The red cysts of H. pluvialis develop thick and rigid cell walls under stress growing conditions. Thus, the biomolecule extraction requires general cell disruption technologies to reach a high recovery rate. This short review provides an analysis of the different steps in H. pluvialis's up and downstream processing including cultivation and harvesting of biomass, cell disruption, extraction and purification techniques. Useful information on the structure of H. pluvialis's cells, biomolecular composition and properties and the bioactivity of astaxanthin is collected. Special emphasis is given to the recent progress in application of different electrotechnologies during the growth stages and for assistance of the recovery of different biomolecules from H. pluvialis.