Astaxanthin attenuates oxidative stress and immune impairment in D-galactose-induced aging in rats by activating the Nrf2/Keap1 pathway and suppressing the NF-κB pathway

Structural characterization, anti-aging activity and mechanisms investigation in vivo of a polysaccharide from Anthriscus sylvestris

Anthriscus sylvestris (L.) Hoffm has a long history of use for anti-aging, although the anti-aging properties of its decoction ingredients have been seldom explored. This study marks the first detailed examination of the in vivo anti-aging activity of A. sylvestris roots polysaccharide (AP). Structural analyses revealed that AP is a neutral heteropolysaccharide with an average molecular weight (Mw) of 34.17 kDa, comprising glucose, xylose, galactose, mannose, and arabinose, with a backbone primarily of 1,4-α-D-Glc and minor branching at 1,4,6-α-D-Man. Its advanced structure is characterized by stable triple-helical chains and nanoscale agglomerated spherical particles. Using a D-gal-induced aging mouse model, further investigation showed that AP boosts the activity of various antioxidant enzymes via the Nrf2/HO-1/NQO1 signaling pathway. Aging-related immune decline was also mitigated by an increase in lymphocyte production in thymus. Moreover, AP reduced inflammation and downregulated aging genes p53 and p21 in hippocampus and liver tissues, enhanced the cholinergic system, and improved liver functions and lipid metabolism. The collective impact of these mechanisms underscores the robust anti-aging properties of AP. These findings highlight the anti-aging and immunomodulatory potential of A. sylvestris polysaccharide, broadening the understanding of its active components.

p-Hydroxy benzaldehyde, a phenolic compound from Nostoc commune, ameliorates DSS-induced colitis against oxidative stress via the Nrf2/HO-1/NQO-1/NF-κB/AP-1 pathway

BACKGROUND

Ulcerative colitis (UC), a chronic idiopathic inflammatory bowel disease (IBD), presents with limited current drug treatment options. Consequently, the search for safe and effective drug for UC prevention and treatment is imperative. Our prior studies have demonstrated that the phenolic compound p-Hydroxybenzaldehyde (HD) from Nostoc commune, effectively mitigates intestinal inflammation. However, the mechanisms underlying HD's anti-inflammatory effects remain unclear.

PURPOSE

This study delved into the pharmacodynamics of HD and its underlying anti-inflammation mechanisms.

METHODS

For in vivo experiments, dextran sodium sulfate (DSS)-induced colitis mouse model was established. In vitro inflammation model was established using lipopolysaccharide (LPS)-induced RAW264.7 and bone marrow-derived macrophages (BMDMs). The protective effect of HD against colitis was determined by monitoring clinical symptoms and histological morphology in mice. The levels of inflammatory factors and oxidative stress markers were subsequently analyzed with enzyme-linked immunosorbent assay (ELISA) and biochemical kits. Furthermore, western blotting (WB), immunofluorescence (IF), luciferase reporter gene, drug affinity reaction target stability (DARTS) assay, molecular docking, and molecular dynamics (MD) simulation were used to determine the potential target and molecular mechanism of HD.

RESULTS

Our findings indicate that HD significantly alleviated the clinical symptoms and histological morphology of colitis in mice, and curtailed the production of pro-inflammatory cytokines, including TNF-α, IL-6, IFN-γ, COX-2, and iNOS. Furthermore, HD stimulated the production of SOD, CAT, and GSH-px, enhanced total antioxidant capacity (T-AOC), and reduced MDA levels. Mechanically, HD augmented the expression of Nrf2, HO-1, and NQO-1, while concurrently downregulating the phosphorylation of p65, IκBα, c-Jun, and c-Fos. ML385 and siNrf2 largely attenuated the protective effect of HD in enteritis mice and RAW 264.7 cells, as well as the promotion of HO-1 expression levels. ZnPP-mediated HO-1 knockdown reversed HD-induced inhibition of colonic inflammation. Luciferase reporter assay and IF assay confirmed the transcriptional activation of Nrf2 by HD. DARTS analysis, molecular docking, and MD results showed high binding strength, interaction efficiency and remarkable stability between Nrf2 and HD.

CONCLUSION

These outcomes extend our previous research results that HD can combat oxidative stress through the Nrf2/HO-1/NQO-1/NF-κB/AP-1 pathways, effectively alleviating colitis, and propose new targets for HD to protect against intestinal barrier damage.

Protective effects of astaxanthin on particulate matter 2.5‑induced senescence in HaCaT keratinocytes via maintenance of redox homeostasis

Particulate matter 2.5 (PM2.5) imposes a heavy burden on the skin and respiratory system of human beings, causing side effects such as aging, inflammation and cancer. Astaxanthin (ATX) is a well-known antioxidant widely used for its anti-inflammatory and anti-aging properties. However, few studies have investigated the protective effects of ATX against PM2.5-induced senescence in HaCaT cells. In the present study, the levels of reactive oxygen species (ROS) and antioxidant enzymes were measured after treatment with PM2.5. The results revealed that PM2.5 generated excessive ROS and reduced the translocation of nuclear factor erythroid 2-related factor 2 (NRF2), subsequently reducing the expression of antioxidant enzymes. However, pretreatment with ATX reversed the ROS levels as well as the expression of antioxidant enzymes. In addition, ATX protected cells from PM2.5-induced DNA damage and rescued PM2.5-induced cell cycle arrest. The levels of senescence-associated phenotype markers, such as interleukin-1β, matrix metalloproteinases, and β-galactosidase, were increased by exposure to PM2.5, however these effects were reversed by ATX. After interfering with NRF2 mRNA expression and exposing cells to PM2.5, the levels of ROS and β-galactosidase were higher compared with siControl RNA cells exposed to PM2.5. However, ATX inhibited ROS and β-galactosidase levels in both the siControl RNA and the siNRF2 RNA groups. Thus, ATX protects HaCaT keratinocytes from PM2.5-induced senescence by partially inhibiting excessive ROS generation via the NRF2 signaling pathway.

Cellular senescence in cancer: molecular mechanisms and therapeutic targets

Aging exhibits several hallmarks in common with cancer, such as cellular senescence, dysbiosis, inflammation, genomic instability, and epigenetic changes. In recent decades, research into the role of cellular senescence on tumor progression has received widespread attention. While how senescence limits the course of cancer is well established, senescence has also been found to promote certain malignant phenotypes. The tumor-promoting effect of senescence is mainly elicited by a senescence-associated secretory phenotype, which facilitates the interaction of senescent tumor cells with their surroundings. Targeting senescent cells therefore offers a promising technique for cancer therapy. Drugs that pharmacologically restore the normal function of senescent cells or eliminate them would assist in reestablishing homeostasis of cell signaling. Here, we describe cell senescence, its occurrence, phenotype, and impact on tumor biology. A "one-two-punch" therapeutic strategy in which cancer cell senescence is first induced, followed by the use of senotherapeutics for eliminating the senescent cells is introduced. The advances in the application of senotherapeutics for targeting senescent cells to assist cancer treatment are outlined, with an emphasis on drug categories, and the strategies for their screening, design, and efficient targeting. This work will foster a thorough comprehension and encourage additional research within this field.

RTA 408 ameliorates diabetic cardiomyopathy by activating Nrf2 to regulate mitochondrial fission and fusion and inhibiting NF-κB-mediated inflammation

Diabetic cardiomyopathy (dCM) is a major complication of diabetes; however, specific treatments for dCM are currently lacking. RTA 408, a semisynthetic triterpenoid, has shown therapeutic potential against various diseases by activating the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. We established in vitro and in vivo models using high glucose toxicity and db/db mice, respectively, to simulate dCM. Our results demonstrated that RTA 408 activated Nrf2 and alleviated various dCM-related cardiac dysfunctions, both in vivo and in vitro. Additionally, it was found that silencing the Nrf2 gene eliminated the cardioprotective effect of RTA 408. RTA 408 ameliorated oxidative stress in dCM mice and high glucose-exposed H9C2 cells by activating Nrf2, inhibiting mitochondrial fission, exerting anti-inflammatory effects through the Nrf2/NF-κB axis, and ultimately suppressing apoptosis, thereby providing cardiac protection against dCM. These findings provide valuable insights for potential dCM treatments.NEW & NOTEWORTHY We demonstrated first that the nuclear factor erythroid 2-related factor 2 (Nrf2) activator RTA 408 has a protective effect against diabetic cardiomyopathy. We found that RTA 408 could stimulate the nuclear entry of Nrf2 protein, regulate the mitochondrial fission-fusion balance, and redistribute p65, which significantly alleviated the oxidative stress level in cardiomyocytes, thereby reducing apoptosis and inflammation, and protecting the systolic and diastolic functions of the heart.

Astaxanthin alleviates chronic prostatitis/chronic pelvic pain syndrome by increasing colonization of Akkermansia muciniphila in the intestine

BACKGROUND

Astaxanthin (AST) is a natural compound with anti-inflammatory/immunomodulatory properties that has been found to have probiotic properties. However, the role and mechanism of AST in chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) are still not fully understood.

PURPOSE

The aim of this study was to evaluate the effect of AST on CP/CPPS and elucidate the mediating role of the gut microbiota.

MATERIALS AND METHODS

An experimental autoimmune prostatitis (EAP) mouse model was utilized to test the potential role of AST on CP/CPPS. Antibiotic cocktail (ABX) treatment and fecal microbiota transplantation (FMT) were used to elucidate the gut microbiota-mediated effects on AST. In addition, 16S rRNA gene sequencing and qRT-PCR analyses were used to analyze changes in the gut microbiota of EAP mice and CP/CPPS patients. Finally, the mechanism by which AST exerts a protective effect on CP/CPPS was explored by untargeted metabolomics and gut barrier function assays.

RESULTS

Oral administration of AST reduced prostate inflammation scores, alleviated tactile sensitization of the pelvic region in EAP mice, reduced CD4+ T cell and CD68+ macrophage infiltration in the prostatic interstitium, and inhibited the up-regulation of systemic and localized pain/pro-inflammatory mediators in the prostate. After ABX, the protective effect of AST against CP/CPPS was attenuated, whereas colonization with fecal bacteria from AST-treated EAP mice alleviated CP/CPPS. 16S rRNA gene sequencing and qRT-PCR analyses showed that Akkermansia muciniphila in the feces of EAP mice and CP/CPPS patients showed a trend toward a decrease, which was associated with poor progression of CP/CPPS. In contrast, oral administration of AST increased the relative abundance of A. muciniphila, and oral supplementation with A. muciniphila also alleviated inflammation and pain in EAP mice. Finally, we demonstrated that both AST and A. muciniphila interventions increased serum levels of SCFAs acetate, up-regulated expression of colonic tight junction markers, and decreased serum lipopolysaccharide levels in EAP mice.

CONCLUSION

Our results showed that AST improved CP/CPPS by up-regulating A. muciniphila, which provides new potentially effective strategies and ideas for CP/CPPS management.

Astaxanthin, Haematococcus pluvialis and Haematococcus pluvialis Residue Alleviate Liver Injury in D-Galactose-induced Aging Mice through Gut-liver Axis

Astaxanthin is a keto-based carotenoid mainly obtained from marine organisms, like Haematococcus pluvialis (H. pluvialis). Previous studies indicated the protective effects of Astaxanthin and H. pluvialis on aging related oxidative injury in liver, while the potential mechanisms are largely unknown. In addition, H. pluvialis residue is a by-product after astaxanthin extraction, which is rarely studied and utilized. The present study aimed to compare the effects of astaxanthin, H. pluvialis and H. pluvialis residue on the oxidant injury of liver in D-galactose-induced aging mice and explore the potential mechanisms through gut-liver axis. The results showed that all the three supplements prevented D-galactose-induced tissue injury, oxidative stress and chronic inflammation in liver and improved liver function. Gut microbiota analysis indicated that astaxanthin notably increased fecal levels of Bacteroidetes, unclassified_f__ Lachnospiraceae, norank_f__Lachnospiraceae, norank_f__norank_o__Clostridia_UCG-014, Prevotellaceae_ UCG-001, unclassified_f__Prevotellaceae in D-galactose-fed mice (p < 0.05). Compared to aging mice, H. pluvialis group had higher fecal levels of norank_f__Lachnospiraceae and Lachnospiraceae_UCG-006 (p < 0.05). H. pluvialis residue group displayed higher relative levels of Bacteroidetes, Streptococcus, and Rikenellaceae_RC9_gut_group (p < 0.05). Moreover, the production of fecal microbial metabolites, like SCFAs and LPS was also differently restored by the three supplements. Overall, our results suggest astaxanthin, H. pluvialis and H. pluvialis residue could prevent aging related hepatic injury through gutliver axis and provide evidence for exploiting of H. pluvialis residue as a functional ingredient for the treatment of liver diseases. Future studies are needed to further clarify the effect and mechanism of dominant components of H. pluvialis residue on liver injury, which is expected to provide a reference for the high-value utilization of H. pluvialis resources.

Anti-Aging Activity and Modes of Action of Compounds from Natural Food Sources

Aging is a natural and inescapable phenomenon characterized by a progressive deterioration of physiological functions, leading to increased vulnerability to chronic diseases and death. With economic and medical development, the elderly population is gradually increasing, which poses a great burden to society, the economy and the medical field. Thus, healthy aging has now become a common aspiration among people over the world. Accumulating evidence indicates that substances that can mediate the deteriorated physiological processes are highly likely to have the potential to prolong lifespan and improve aging-associated diseases. Foods from natural sources are full of bioactive compounds, such as polysaccharides, polyphenols, carotenoids, sterols, terpenoids and vitamins. These bioactive compounds and their derivatives have been shown to be able to delay aging and/or improve aging-associated diseases, thereby prolonging lifespan, via regulation of various physiological processes. Here, we summarize the current understanding of the anti-aging activities of the compounds, polysaccharides, polyphenols, carotenoids, sterols, terpenoids and vitamins from natural food sources, and their modes of action in delaying aging and improving aging-associated diseases. This will certainly provide a reference for further research on the anti-aging effects of bioactive compounds from natural food sources.

Antioxidant and Anti-Aging Properties of Polyphenol-Polysaccharide Complex Extract from Hizikia fusiforme

Hizikia fusiforme has a long history of consumption and medicinal use in China. It has been found that natural plants containing polyphenol-polysaccharide complexes have better activity compared with polyphenols and polysaccharides. Therefore, in this study on enzymatic hydrolysis and fractional alcohol precipitation, two kinds of polyphenol-polysaccharide complexes (PPC), PPC1 and PPC2, were initially obtained from Hizikia fusiforme, while the dephenolization of PPC1 and PPC2 produced PPC3 and PPC4. Through in vitro assays, PPC2 and PPC4 were found to have higher antioxidant activity, and thus were selected for testing the PPCs' anti-aging activity in a subsequent in vivo experiment with D-gal-induced aging in mice. The results indicated that PPCs could regulate the expressions of antioxidant enzymes and products of oxidation, elevate the expressions of genes and proteins related to the Nrf2 pathway in the mouse brain, enrich the gut microbiota species and increase the Bacteroidota-Firmicute (B/F) ratio. Above all, the Hizikia fusiforme polyphenol-polysaccharide complex has potential in the development of natural anti-aging drugs.

Effect of Lactobacillus brevis (MG000874) on antioxidant-related gene expression of the liver and kidney in D-galactose-induced oxidative stress mice model

Oxidative stress (OS) is a phenomenon induced by excessive production and accumulation of reactive oxygen species (ROS) in living cells. These increased ROS productions connected, coupled with many neurological and physiological diseases. Several antioxidants were utilized recently to combat OS, and lactic acid bacteria have a potent radical-scavenging activity to minimize OS. The present work was designed to find out the protective effects of Lactobacillus brevis MG000874 (L. brevis MG000874) against oxidative injuries induced by D-galactose (D-gal) in vivo and to explore the gene expression of OS-related gene mice. Sixty male mice were randomly split into six groups. The first four groups were different control groups as no treatment (N), positive (G), probiotic (B), and ascorbic acid (A); the remaining two groups were treatment groups such as probiotic treatment (BG) and ascorbic acid treatment (AG). L. brevis MG000874 (0.2 ml of 1010 CFU/ml) and ascorbic acid (0.2 ml of 25 mg/ml) were administered orally daily for 5 weeks. It was revealed that these significantly affect the weight of treated mice: 40.22 ± 1.5 and 33.0 ± 0.57 g on days 0 and 36, respectively. D-gal induction in mice declined the levels of SOD and CAT determined by spectrophotometer. Administration of L. brevis MG000874 improved the antioxidant status of the stress mice and recovered the antioxidant activities of SOD and CAT enzymes. In addition, L. brevis MG000874-altered gene expression of OS marker at the messenger RNA (mRNA) levels was determined by RT-PCR in the mouse model. L. brevis MG000874 significantly improved the GST, GPX, SOD, CAT, and ß-actin levels in the kidney and the liver of the D-gal-induced mice (p < 0.05). Moreover, the histological investigation indicated that L. brevis MG000874 mitigated damage to the kidney and liver effectively in mice induced by D-gal. Therefore, it could be concluded from the current results that L. brevis MG000874 may act as a powerful antioxidant agent, and this study can provide the baseline data for drug development against OS-linked diseases.

Celastrol alleviates oxidative stress induced by multi-walled carbon nanotubes through the Keap1/Nrf2/HO-1 signaling pathway

Multi-walled carbon nanotubes (MWCNTs) mainly induce oxidative stress through the overproduction of reactive oxygen species (ROS), which can lead to cytotoxicity. Celastrol, a plant-derived compound, can exert antioxidant effects by reducing ROS production. Our results indicated that exposure to MWCNTs decreased cell viability and increased ROS production. Nrf2 knockdown (kd) led to increased ROS production and enhanced MWCNT-induced cytotoxicity. Keap1-kd led to decreased ROS production and attenuated cytotoxicity. Treatment with celastrol significantly decreased ROS production and promoted Keap1 protein degradation through the lysosomal pathway, thereby enhancing the translocation of Nrf2 from the cytoplasm to the nucleus and increasing HO-1 expression. The in vivo results showed that celastrol could alleviate the inflammatory damage of lung tissues, increase the levels of the antioxidants, GSH and SOD, as well as promote the expression of the antioxidant protein, HO-1 in MWCNT-treated mice. Celastrol can alleviate MWCNT-induced oxidative stress through the Keap1/Nrf2/HO-1 signaling pathway.

Acute Aluminum Sulfate Triggers Inflammation and Oxidative Stress, Inducing Tissue Damage in the Kidney of the Chick

In this study, a total of 20 7-day-old chicks were randomly divided into an experimental group and a control group. The experimental group was administered aluminum sulfate (Al₂(SO₄)₃) once by gavage, and the control group was sacrificed after 24 h of fasting with distilled water. Serum and kidney tissue samples from both groups were collected and compared using hematoxylin-eosin staining (H&E) and microscopy. The Paller scores increased (p < 0.01) for biochemical kidney function, redox-related indicators, and mRNA expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) downstream related genes. The results showed that in the kidneys of the experimental group, renal tubular epithelial cells appeared to swell, and there was necrosis and shedding; the blood urea nitrogen (BUN) and uric acid (UA) decreased, serum creatinine (CREA) increased; nitric oxide (NO), glutathione (GSH), and malondialdehyde (MDA) contents increased; NO synthase (NOS), glutathione peroxidase (GSH-PX), and superoxide dismutase (SOD) enzyme activities increased; tumor necrosis factor alpha (TNF-α), tumor necrosis factor receptor 1 (TNF-R1), tumor necrosis factor receptor 2 (TNF -R2), cyclooxygenase-2 (COX-2), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and heme oxygenase-1 (HO-1) mRNA expression levels increased (p < 0.05 or p < 0.01); Nrf2, glutathione S-transferase A3 (GSTA3), glutathione-S-transferase mu-1 (GSTM1), glutathione synthetase (GSS), glutamate cysteine ligase (GCLC and GCLM), quinone oxidoreductase 1 (NQO1), and Kelch-like ECH-associated protein 1 (Keap1) mRNA expression levels decreased (p < 0.05 or p < 0.01) compared to the control group. Acute aluminum poisoning can cause obvious pathological changes in the structure of the kidney tissue of the chick, resulting in damage to the kidney function, as well as triggering inflammation and oxidative stress in the kidney.

Emerging cellular senescence-centric understanding of immunological aging and its potential modulation through dietary bioactive components

Immunological aging is strongly associated with the observable deleterious effects of human aging. Our understanding of the causes, effects, and therapeutics of aging immune cells has long been considered within the sole purview of immunosenescence. However, it is being progressively realized that immunosenescence may not be the only determinant of immunological aging. The cellular senescence-centric theory of aging proposes a more fundamental and specific role of immune cells in regulating senescent cell (SC) burden in aging tissues that has augmented the notion of senescence immunotherapy. Now, in addition, several emerging studies are suggesting that cellular senescence itself may be prevalent in aging immune cells, and that senescent immune cells exhibiting characteristic markers of cellular senescence, similar to non-leucocyte cells, could be among the key drivers of various facets of physiological aging. The present review integrates the current knowledge related to immunosenescence and cellular senescence in immune cells per se, and aims at providing a cohesive overview of these two phenomena and their significance in immunity and aging. We present evidence and rationalize that understanding the extent and impact of cellular senescence in immune cells vis-à-vis immunosenescence is necessary for truly comprehending the notion of an 'aged immune cell'. In addition, we also discuss the emerging significance of dietary factors such as phytochemicals, probiotic bacteria, fatty acids, and micronutrients as possible modulators of immunosenescence and cellular senescence. Evidence and opportunities related to nutritional bioactive components and immunological aging have been deliberated to augment potential nutrition-oriented immunotherapy during aging.

Recent advances in the bio-application of microalgae-derived biochemical metabolites and development trends of photobioreactor-based culture systems

Microalgae are microscopic algae in sizes ranging from a few micrometers to several hundred micrometers. On average, half of the oxygen in the atmosphere is produced by the photosynthetic process of microalgae, so the role of these microorganisms in the life cycle of the planet is very significant. Pharmaceutical products derived from microalgae and commercial developments of a variety of supplements extracted from them originate from a variety of their specific secondary metabolites. Many of these microalgae are a reservoir of unique biological compounds including carotenoids, antioxidants, fatty acids, polysaccharides, enzymes, polymers, peptides, pigments, toxins and sterols with antimicrobial, antiviral, antifungal, antiparasitic, anticoagulant, and anticancer properties. The present work begins with an introduction of the importance of microalgae in renewable fuels and biodiesel production, the development of healthy food industry, and the creation of optimal conditions for efficient biomass yield. This paper provides the latest research related to microalgae-derived substances in the field of improving drug delivery, immunomodulatory, and anticancer attributes. Also, the latest advances in algal biocompounds to combat the COVID-19 pandemic are presented. In the subject of cultivation and growth of microalgae, the characteristics of different types of photobioreactors, especially their latest forms, are fully discussed along with their advantages and obstacles. Finally, the potential of microalgae biomass in biotechnological applications, biofuel production, as well as various biomass harvesting methods are described.

Accelerated Bone Regeneration by an Astaxanthin-Modified Antioxidant Aerogel through Relieving Oxidative Stress via the NRF2 Signaling Pathway

Bone regeneration of critical-sized bone defects (CSBDs) with biomimetic collagen-based aerogels remains a significant challenge due to the oxidative stress on the microenvironment. The excessive oxidative stress could induce apoptosis and dysfunction of host-derived cells. Astaxanthin (ATX) exhibits excellent antioxidant ability to block free radical chain reactions. In the present study, hybrid antioxidant collagen-derived aerogels (ATX-Col aerogels) were fabricated by a simple one-step method through the covalent cross-linking of Col and ATX. The resulting ATX-Col aerogels show porous and interconnected structures due to freeze-drying strategies. The ATX-Col aerogels exhibited excellent biocompatibility and biosafety. Furthermore, ATX-Col aerogels demonstrated favorable antioxidant capacity by eliminating intracellular ROS by activating the NRF2 signaling pathway. Finally, excellent reparative effects in repairing rat cranial defects were observed in ATX-Col aerogels. Taken together, ATX-Col aerogels can accelerate bone regeneration by relieving oxidative stress via the NRF2 signaling pathway and act as a potential bone graft for CSBD. This study provides a simple method of developing antioxidant aerogels for bone regeneration.

Signal pathways in the treatment of Alzheimer's disease with traditional Chinese medicine

AIM OF THE REVIEW

This study aimed to reveal the classical signal pathways and important potential targets of traditional Chinese medicine (TCM) for treating Alzheimer's disease (AD), and provide support for further investigation on TCM and its active ingredients.

MATERIALS AND METHODS

Literature survey was conducted using PubMed, Web of Science, Google Scholar, CNKI, and other databases, with "Alzheimer's disease," "traditional Chinese medicine," "medicinal herb," "Chinese herb," and "natural plant" as the primary keywords.

RESULTS

TCM could modulate signal pathways related to AD pathological progression, including NF-κB, Nrf2, JAK/STAT, ubiquitin-proteasome pathway, autophagy-lysosome pathway-related AMPK/mTOR, GSK-3/mTOR, and PI3K/Akt/mTOR, as well as SIRT1 and PPARα pathway. It could regulate crosstalk between pathways through a multitarget, thus maintaining chronic inflammatory interaction balance, inhibiting oxidative stress damage, regulating ubiquitin-proteasome system function, modulating autophagy, and eventually improving cognitive impairment in patients with AD.

CONCLUSION

TCM could be multilevel, multitargeted, and multifaceted to prevent and treat AD. In-depth research on the prevention and treatment of AD with TCM could provide new ideas for exploring the pathogenesis of AD and developing new anti-AD drugs.

PIN1-mediated ROS production is involved in antagonism of N-acetyl-L-cysteine against arsenic-induced hepatotoxicity

Arsenic, a widely existing environmental contaminant, is recognized to be toxic to multiple organs. Exposure to arsenic results in liver damage via excessive production of reactive oxidative species (ROS). PIN1 regulates the levels of ROS. N-acetyl-L-cysteine (NAC) is an ROS scavenger that protects the hepatic functions. Whether PIN1 plays a regulatory role in NAC-mediated antagonism against arsenic hepatotoxicity remains largely unknown. In our study, the protective effects of NAC against arsenic (NaAsO2)-induced hepatotoxicity were evaluated in vitro and in vivo. Arsenic exposure induced cytotoxicity by increasing the intracellular ROS production, impairing mitochondrial function and inducing apoptosis in L02 hepatocytes. Overexpression of PIN1 markedly protected against arsenic cytotoxicity, decreased ROS levels, and mitigated mitochondrial dysfunction and apoptosis in L02 cells. However, loss of PIN1 further aggravated arsenic-induced cytotoxicity and abolished the protective effects of NAC in L02 cells. An in vivo study showed that pretreatment with NAC rescued arsenic-induced liver injury by restoring liver function and suppressing hepatic oxidative stress. Overexpression of PIN1 in mice transfected with AAV-Pin1 relieved arsenic-induced liver dysfunction and hepatic oxidative stress. Taken together, our study identified PIN1 as a novel intervention target for antagonizing arsenic-induced hepatotoxicity, highlighting a new pharmacological mechanism of NAC targeting PIN1 in antagonism against arsenic toxicity.

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

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

New Insights Into the Persistent Effects of Acute Exposure to AFB1 on Rat Liver

Aflatoxin B₁ (AFB₁) has mutagenesis, carcinogenesis and teratogenesis effects and mainly found in food crops and their processed foods. AFB₁ exposure can cause acute or chronic liver poisoning, but there were few studies on the persistent effects of acute AFB₁ exposure on the liver. In this study, rat liver injury models were established 2 and 7 days after single exposure to high and low doses of AFB₁. The persistent effects of AFB₁ single acute exposure (ASAE) on rat liver were analyzed from the phenotypic and genetic levels. The results showed that compared with the control group, liver function indexes, MDA content in liver and the number of apoptotic hepatocytes in model groups increased to the highest on the 2nd day after ASAE (p < 0.001). However, the changes of liver coefficient were most significant on the 7th day after ASAE (p < 0.01). The results of liver pathology showed that the liver injury was not alleviated and the activities of antioxidant enzymes GSH-Px and SOD were the lowest on the 7th day (p < 0.001). RNA-Seq results indicated that there were 236, 33, 679, and 78 significantly differentially expressed genes (DEGs) in the model groups (LA-2d, LA-7d, HA-2d, HA-7d) compared with the control group. Among them, the Gtse1 gene related to the proliferation, differentiation and metastasis of liver cancer cells, the Lama5 and Fabp4 gene related to the inflammatory response were significantly DEGs in the four model groups, and the differential expression of the immune system-related Bcl6 gene increased with the prolonged observation time after ASAE. In conclusion, ASAE can cause persistent liver damage in rats. The persistently affected genes Lama5, Gtse1, Fabp4, and Bcl6 possess the potential to be therapeutic targets for liver disease induced by AFB₁.

Astaxanthin attenuates cardiovascular dysfunction associated with deoxycorticosterone acetate-salt-induced hypertension in rats

BACKGROUND

Hypertension is a major global health problem. It is a major risk factor of cardiovascular disease. One of the most used experimental models in studying antihypertensive action is the deoxycorticosterone acetate (DOCA)-salt hypertensive rat. This study aimed to investigate the cardiovascular protective effect of astaxanthin (ASX) in DOCA-salt-induced hypertension and its possible underlying mechanisms.

METHODS

A total of 48 adult male Wistar albino rats were divided into three groups: control, DOCA, and DOCA + ASX. Blood pressure, serum cardiac enzyme levels, some oxidative stress and inflammatory biomarker levels, and lipid profile levels were measured. The weight of the left ventricle to tibial length ratio was calculated. Apoptosis detection and total genomic DNA extraction in aortic and cardiac tissues were investigated. The apoptotic marker BAX was also immunohistochemically assessed in the heart and aorta.

RESULTS

Compared to the control group, the DOCA group was associated with a significant increase in blood pressure, serum cardiac enzyme levels, oxidative stress and inflammatory biomarker levels, lipid profile except serum high-density lipoprotein (HDL), weight of the left ventricle to tibial length, and total released DNA fragmentation level of the left ventricle and aorta and a significant decrease in reduced glutathione (GSH) and HDL. Compared to the DOCA group, the DOCA + ASX group significantly improved the DOCA-induced changes.

CONCLUSION

ASX has beneficial protective effects on DOCA-salt-induced hypertension via DNA fragmentation protection, apoptosis inhibition, antioxidant, anti-inflammatory, and its effects on lipid levels.

Randomized controlled trial of astaxanthin impacts on antioxidant status and assisted reproductive technology outcomes in women with polycystic ovarian syndrome

PURPOSE

Polycystic ovary syndrome (PCOS), the most common endocrinopathy in women, is typically accompanied by a defective oxidative defense system. Here, we investigated the effect of astaxanthin (AST) as a powerful antioxidant on the oxidative stress (OS) response and assisted reproductive technology (ART) outcomes in PCOS patients.

METHODS

In this double-blind, randomized, placebo-controlled trial, PCOS patients were randomly assigned into two groups. The intervention group received 8 mg AST, and the control group received the placebo daily for 40 days. The primary outcomes were the serum and follicular fluid (FF) levels of the OS biomarkers and the expression levels of the specific genes and proteins in the oxidative stress response pathway. The secondary outcomes were considered ART outcomes.

RESULTS

According to our findings, a 40-day course of AST supplementation led to significantly higher levels of serum CAT and TAC in the AST group compared to the placebo group. However, there were no significant intergroup differences in the serum MDA and SOD levels, as well as the FF levels of OS markers. The expression of Nrf2, HO-1, and NQ-1 was significantly increased in the granulosa cells (GCs) of the AST group. Moreover, the MII oocyte and high-quality embryo rate were significantly increased in the AST group compared to the placebo group. We found no significant intergroup difference in the chemical and clinical pregnancy rates.

CONCLUSION

AST treatment has been shown to increase both serum TAC levels and activation of the Nrf2 axis in PCOS patients' GCs.

TRIAL REGISTRATION

ClincialTrials.gov Identifier: NCT03991286.

Astaxanthin as a Modulator of Nrf2, NF-κB, and Their Crosstalk: Molecular Mechanisms and Possible Clinical Applications

Astaxanthin (AST) is a dietary xanthophyll predominantly found in marine organisms and seafood. Due to its unique molecular features, AST has an excellent antioxidant activity with a wide range of applications in the nutraceutical and pharmaceutical industries. In the past decade, mounting evidence has suggested a protective role for AST against a wide range of diseases where oxidative stress and inflammation participate in a self-perpetuating cycle. Here, we review the underlying molecular mechanisms by which AST regulates two relevant redox-sensitive transcription factors, such as nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor κB (NF-κB). Nrf2 is a cellular sensor of electrophilic stress that coordinates the expression of a battery of defensive genes encoding antioxidant proteins and detoxifying enzymes. Likewise, NF-κB acts as a mediator of cellular stress and induces the expression of various pro-inflammatory genes, including those encoding cytokines, chemokines, and adhesion molecules. The effects of AST on the crosstalk between these transcription factors have also been discussed. Besides this, we summarize the current clinical studies elucidating how AST may alleviate the etiopathogenesis of oxidative stress and inflammation.

Limonin Inhibits IL-1β-Induced Inflammation and Catabolism in Chondrocytes and Ameliorates Osteoarthritis by Activating Nrf2

Osteoarthritis (OA), a degenerative disorder, is considered to be one of the most common forms of arthritis. Limonin (Lim) is extracted from lemons and other citrus fruits. Limonin has been reported to have anti-inflammatory effects, while inflammation is a major cause of OA; thus, we propose that limonin may have a therapeutic effect on OA. In this study, the therapeutic effect of limonin on OA was assessed in chondrocytes in vitro in IL-1β induced OA and in the destabilization of the medial meniscus (DMM) mice in vivo. The Nrf2/HO-1/NF-κB signaling pathway was evaluated to illustrate the working mechanism of limonin on OA in chondrocytes. In this study, it was found that limonin can reduce the level of IL-1β induced proinflammatory cytokines such as INOS, COX-2, PGE2, NO, TNF-α, and IL-6. Limonin can also diminish the biosynthesis of IL-1β-stimulated chondrogenic catabolic enzymes such as MMP13 and ADAMTS5 in chondrocytes. The research on the mechanism study demonstrated that limonin exerts its protective effect on OA through the Nrf2/HO-1/NF-κB signaling pathway. Taken together, the present study shows that limonin may activate the Nrf2/HO-1/NF-κB pathway to alleviate OA, making it a candidate therapeutic agent for OA.

Vitamin D3 Protects Mice from Diquat-Induced Oxidative Stress through the NF-κB/Nrf2/HO-1 Signaling Pathway

Vitamin D3, as an indispensable and fat-soluble micronutrient, plays an important role in the health of humans and animals. At present, studies are focusing on the calcium absorption and immunoregulation function of vitamin D3; this study was aimed at exploring the antioxidative stress ability of vitamin D3 on diquat-induced intestinal dysfunction of ICR mice and the underlying mechanism. The results showed that oral gavage of vitamin D3 daily significantly improved the body weight gain and immune organ index and significantly reverted the abnormal changes of ALT, AST, SOD, GSH-Px, T-AOC, and MDA in the serum and jejunum induced by diquat. The addition of vitamin D3 also significantly reduced the concentration of DAO, D-LA, and certain proinflammatory cytokines in serum. Moreover, vitamin D3 improved the pathological morphology of the duodenum, jejunum, colon, liver, and kidney tissues, and it also largely attenuated the degree of inflammatory infiltration of macrophages and cell apoptotic index of jejunal epithelial tissue induced by diquat. The results demonstrated that vitamin D3 significantly recovered the intestinal barrier injury by enhancing the expression of mucins and tight junction proteins in the jejunum. In addition, the results indicated that vitamin D3 could significantly reduce the phosphorylation level of NF-κB (p65) and enhance the expression of Nrf2 and HO-1 in the jejunum compared with the diquat-induced group. This study suggested that oral administration of vitamin D3 can protect mice against oxidative damage by inhibiting the phosphorylation level of NF-κB (p65) and activating Nrf2-related signaling pathways.

Carotenoids: Therapeutic Strategy in the Battle against Viral Emerging Diseases, COVID-19: An Overview

Carotenoids, a group of phytochemicals, are naturally found in the Plant kingdom, particularly in fruits, vegetables, and algae. There are more than 600 types of carotenoids, some of which are thought to prevent disease, mainly through their antioxidant properties. Carotenoids exhibit several biological and pharmaceutical benefits, such as anti-inflammatory, anti-cancer, and immunity booster properties, particularly as some carotenoids can be converted into vitamin A in the body. However, humans cannot synthesize carotenoids and need to obtain them from their diets or via supplementation. The emerging zoonotic virus severe acute respiratory syndrome coronavirus 2, which causes coronavirus disease 2019 (COVID-19), originated in bats, and was transmitted to humans. COVID-19 continues to cause devastating international health problems worldwide. Therefore, natural preventive therapeutic strategies from bioactive compounds, such as carotenoids, should be appraised for strengthening physiological functions against emerging viruses. This review summarizes the most important carotenoids for human health and enhancing immunity, and their potential role in COVID-19 and its related symptoms. In conclusion, promising roles of carotenoids as treatments against emerging disease and related symptoms are highlighted, most of which have been heavily premeditated in studies conducted on several viral infections, including COVID-19. Further in vitro and in vivo research is required before carotenoids can be considered as potent drugs against such emerging diseases.

Wan-Nian-Qing, a Herbal Composite Prescription, Suppresses the Progression of Liver Cancer in Mice by Regulating Immune Response

The Wan-Nian-Qing prescription (WNQP), an herbal composite containing Ornithogalum caudatum, has been used in China for several years for cancer treatment. However, the mechanism of its pharmacological action against liver cancer is not clear. This study aimed to investigate the role of WNQP in inhibiting tumor growth in hepatocellular carcinoma model mice and determine its mechanism of action. We established HepG2- and SMMC-7721-xenografted tumor models in nude mice and BALB/c mice. The mice were administered WNQP for 2 weeks. The bodyweight of each mouse was monitored every day, and the tumor size was measured using vernier caliper before each round of WNQP administration. After the last dose, mice were sacrificed. The tumors were removed, lysed, and subjected to proteome profiling, enzyme-linked immunosorbent assay, and western blotting. The liver, spleen, and kidney were collected for histopathological examination. The effects of WNQP against liver cancer were first systematically confirmed in HepG2- and SMMC-7721-xenografted nude mice and BALB/c mice models. WNQP inhibited tumor growth, but failed to affect bodyweight and organ structures (liver and spleen), confirming that it was safe to use in mice. In BALB/c mice, WNQP regulated immune function, inferred from the modulation of immune-related cytokines such as interleukins, interferon, tumor necrosis factors, and chemokines. Further results confirmed that this regulation occurred via the regulatory effects of WNQP on Nrf2 signaling. WNQP can inhibit the growth of HepG2- and SMMC-7721-xenografted tumors in nude mice and BALB/c mice. This effect manifests at least partially through immunomodulation mediated apoptosis.

Antioxidant activity of Lactobacillus plantarum NJAU-01 in an animal model of aging

BACKGROUND

Excessive reactive oxygen species (ROS) can cause serious damage to the human body and may cause various chronic diseases. Studies have found that lactic acid bacteria (LAB) have antioxidant and anti-aging effects, and are important resources for the development of microbial antioxidants. This paper was to explore the potential role of an antioxidant strain, Lactobacillus plantarum NJAU-01 screened from traditional dry-cured meat product Jinhua Ham in regulating D-galactose-induced subacute senescence of mice. A total of 48 specific pathogen free Kun Ming mice (SPF KM mice) were randomly allocated into 6 groups: control group with sterile saline injection, aging group with subcutaneously injection of D-galactose, treatments groups with injection of D-galactose and intragastric administration of 107, 108, and 109 CFU/mL L. plantarum NJAU-01, and positive control group with injection of D-galactose and intragastric administration of 1 mg/mL Vitamin C.

RESULTS

The results showed that the treatment group of L. plantarum NJAU-01 at 109 CFU/mL showed higher total antioxidant capacity (T-AOC) and the antioxidant enzymatic activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) than those of the other groups in serum, heart and liver. In contrast, the content of the oxidative stress marker malondialdehyde (MDA) showed lower levels than the other groups (P < 0.05). The antioxidant capacity was improved with the supplement of the increasing concentration of L. plantarum NJAU-01.

CONCLUSIONS

Thus, this study demonstrates that L. plantarum NJAU-01 can alleviate oxidative stress by increasing the activities of enzymes involved in oxidation resistance and decreasing level of lipid oxidation in mice.

Microorganisms: A Potential Source of Bioactive Molecules for Antioxidant Applications

Oxidative stress originates from an elevated intracellular level of free oxygen radicals that cause lipid peroxidation, protein denaturation, DNA hydroxylation, and apoptosis, ultimately impairing cell viability. Antioxidants scavenge free radicals and reduce oxidative stress, which further helps to prevent cellular damage. Medicinal plants, fruits, and spices are the primary sources of antioxidants from time immemorial. In contrast to plants, microorganisms can be used as a source of antioxidants with the advantage of fast growth under controlled conditions. Further, microbe-based antioxidants are nontoxic, noncarcinogenic, and biodegradable as compared to synthetic antioxidants. The present review aims to summarize the current state of the research on the antioxidant activity of microorganisms including actinomycetes, bacteria, fungi, protozoa, microalgae, and yeast, which produce a variety of antioxidant compounds, i.e., carotenoids, polyphenols, vitamins, and sterol, etc. Special emphasis is given to the mechanisms and signaling pathways followed by antioxidants to scavenge Reactive Oxygen Species (ROS), especially for those antioxidant compounds that have been scarcely investigated so far.

Nrf2 a molecular therapeutic target for Astaxanthin

Astaxanthin (ATX) is a red pigment carotenoid present in shrimp, salmon, crab, and asteroidean. Several studies have corroborated the anti-oxidant efficacy of ATX. In addition, ATX has anti-inflammatory, anti-apoptotic and anti-proliferative properties. In the present review, we discuss the role of Nrf2 in mediating the anti-cancer, anti-aging, neuroprotective, lung-protective, skin-protective, cardioprotective, hepatoprotective, anti-diabetic and muscloprotective effects of ATX.