Anti-Neuroinflammatory Effects of Fucoxanthin via Inhibition of Akt/NF-κB and MAPKs/AP-1 Pathways and Activation of PKA/CREB Pathway in Lipopolysaccharide-Activated BV-2 Microglial Cells

Fucoxanthin alleviates secondary brain injury in mice following intracerebral hemorrhage via PI3K-mediated inhibition of NF-κB signaling pathway

BACKGROUND

ICH is an acute clinical cerebrovascular disease without effective treatments. This study was designed to investigate the therapeutic value of fucoxanthin in ICH treatment.

METHODS

Animal ICH models were established by collagenase IV injection. ICH mice were given intraperitoneal injection of fucoxanthin (100 mg/kg). Neurological deficits, brain edema, blood-brain barrier (BBB) integrity, and histological impairment were assessed. Nissl staining and TUNEL staining were performed to detect neuronal cell loss and apoptosis. The levels of tight junction proteins, apoptosis-related proteins, Iba-1, and pathway-related proteins were measured by immunofluorescence staining, western blotting, and ELISA.

RESULTS

Fucoxanthin administration attenuated neurological deficits and brain injuries following ICH. Additionally, fucoxanthin alleviated neuronal apoptosis caused by ICH. Moreover, fucoxanthin inhibited microglia-mediated inflammation and M1 polarization in ICH models. Mechanistically, fucoxanthin inactivated the NF-κB pathway and triggered the activation of PI3K/Akt signaling after ICH, and LY294002 (a PI3K inhibitor) compromised the protective effect of fucoxanthin.

CONCLUSION

Fucoxanthin alleviates ICH-induced neurological deficits and brain injuries by suppressing the PI3K/Akt-mediated NF-κB pathway to inhibit M1 polarization and attenuate neuroinflammation, neuronal apoptosis, BBB dysfunction, and brain edema.

Long-term fucoxanthin treatment prevents cognitive impairments and neuroinflammation via the inhibition of Nogo-A in APP/PS1 transgenic mice

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by neuroinflammation and cognitive impairments. Although short-term treatment with fucoxanthin, a marine carotenoid with anti-neuroinflammatory activity, has been reported to prevent cognitive impairments in scopolamine- and β-amyloid (Aβ)-treated mice, it remains uncertain whether long-term fucoxanthin treatment could produce similar effects in transgenic AD models. Moreover, the anti-neuroinflammatory mechanism of fucoxanthin is still unclear. In this study, long-term treatment with fucoxanthin (15-150 mg kg-1, twice a week for 20 weeks) significantly prevented cognitive deficits and Aβ-related neuroinflammation in APP/PS1 transgenic mice. In addition, fucoxanthin largely prevented Aβ oligomer-induced secretion of pro-inflammatory cytokines and the activation of BV2 microglial cells. Furthermore, fucoxanthin reduced the increased expression of Nogo-A, a central player in AD pathophysiology, as well as the activation of downstream Rho-associated protein kinase 2 (ROCK2) and nuclear factor kappa-B (NF-κB) pathways in AD models. Most importantly, the inhibition of neuroinflammation by fucoxanthin was not reduced by shRNA-mediated knockdown of Nogo-A, suggesting that fucoxanthin significantly prevented cognitive impairments and neuroinflammation via the inhibition of Nogo-A. These results not only elucidate an anti-neuroinflammatory mechanism of fucoxanthin, but also provide strong support for the development of fucoxanthin as a novel food ingredient or drug for the treatment of AD.

Bioactive compounds and dietary patterns in Alzheimer's disease

Alzheimer's disease (AD) is a progressive neurodegenerative disorder that primarily affects the elderly, leading to severe cognitive decline and loss of autonomy. The accumulation of amyloid-β peptides and tau proteins in the brain is considered the central pathogenic mechanism, which results in neuronal dysfunction and cell death. Various metabolic disruptions, such as chronic oxidative stress and inflammatory processes, further exacerbate the progression of AD. This review, based on literature from PubMed, SciELO, MDPI, and ScienceDirect, evaluates the role of bioactive compounds and dietary patterns, specifically the Mediterranean and MIND diets, in mitigating the progression of AD. These diets, rich in vitamins, flavonoids, carotenoids, and omega-3 fatty acids, have shown potential in reducing oxidative damage and inflammation in the brain, offering neuroprotective benefits. The findings suggest that bioactive compounds such as vitamin E isomers and polyphenols may delay cognitive decline, presenting a promising avenue for future dietary interventions aimed at optimizing the consumption of these compounds to prevent or slow the onset of AD. Further research is needed to determine the optimal doses and combinations of these bioactive compounds to maximize their protective effects.

Association of serum carotenoids and SII among general people, based on NHANES 2001-2006

As a novel inflammatory marker, Systemic Immune-Inflammation Index (SII) has recently been recognized as a prognostic indicator for a variety of diseases including malignant cancers, coronary artery disease, hyperlipidemia, and hepatic steatosis. Carotenoids are a group of abundant lipid-soluble phytochemicals, and studies have suggested that they have antioxidant, antiapoptotic, and anti-inflammatory properties. However, a systematic analysis of the association between serum carotenoids and SII is still lacking. The purpose of this investigation was to explore the association between serum carotenoid concentration and SII. The cross-sectional investigation included general people (age ≥ 20) with complete information on SII and five different serum carotenoids (Trans-lycopene, β-carotene, α-carotene, lutein/zeaxanthin, and β-cryptoxanthin). Multivariate linear regression analyses were used to evaluate the association between serum carotenoids and SII among general people. The potential non-linear relationship was determined using threshold effect analysis and fitted smoothing curves. Subgroup analysis was performed to explore the potential stratified factors. 15903 participants were enrolled in our investigation. Based on multivariate linear regressions, the highest quartiles of serum carotenoids were found significantly associated with SII compared with the lowest quartiles. The results showed the negative association between SII and the concentration of five different serum carotenoids. According to the non-linear analysis, we found that there are non-linear relationships between β-carotene and trans-lycopene and SII in general people with an inflection point of 6.90 (log2-transformed, ug/dL) and 4.01 (log2-transformed, ug/dL), respectively. The results from subgroup analysis provide several potential moderating effects, such as race, current drinker, and age. This study revealed the relationship between the concentration of several serum carotenoids and SII across the general American population. Further prospective and longitude investigations are needed.

The Advancements of Marine Natural Products in the Treatment of Alzheimer's Disease: A Study Based on Cell and Animal Experiments

As life expectancy rises and the aging population grows, Alzheimer's disease (AD) has become a significant global health concern. AD is a complex neurodegenerative disorder with an unclear etiology. Current hypotheses primarily focus on β-amyloid (Aβ) aggregation, tau protein hyperphosphorylation, and neuroinflammation as key pathological processes. Given the limited efficacy of existing therapeutic strategies, there is an urgent need to explore novel treatment options. Marine natural products have garnered significant attention due to their unique chemical structures and diverse bioactivities, demonstrating potential for multi-target interventions in AD. This review systematically summarizes the roles of marine-derived compounds, including polysaccharides, carotenoids, and polyphenols, in modulating Aβ aggregation, mitigating tau protein pathology, and regulating gut-brain axis dysfunction. Furthermore, the challenges of current research are discussed, with an emphasis on improving blood-brain barrier permeability and optimizing drug delivery systems to facilitate clinical translation.

Non-Invasive Imaging for the Evaluation of a New Oral Supplement in Skin Aging: A Case-Controlled Study

BACKGROUND

Skin aging represents a para-physiological process related to metabolic imbalances, inflammation, proliferative responses, and oxidative stress. Ending the cycle of inflammation, and oxidative stress represents a way to slow the effects of aging.

STUDY OBJECTIVE

The aim of our study was to evaluate the benefits of supplements with an herbal mixture based on Venerinase and B-group vitamins, Zinc, and Magnesium in preventing/reducing photoaging by means of objective quantitative analysis of visual skin features obtained by VISIA 2D and stroma and vascular characteristics measured by Optical Coherence Tomography (OCT).

METHODS

A prospective clinical study was conducted in 40 participants. They were randomized 1:1 to receive the supplement (Giovina) or placebo. Assessments were conducted at Baseline (T0), after 2 months (T1), and after 4 months (T2). The primary endpoint was to obtain a significant improvement in facial photo/chrono-aging in the treatment arm, as assessed through the evaluation of the Griffith scale. Secondary endpoints were to assess significant changes in skin aging objective features (VISIA) and Optical Coherence Tomography (OCT) parameters.

RESULTS

The treated group showed a significant reduction in the mean Griffith scale score from 4.5 at baseline to 3.76 at T2 (4 months) (p = 0.001). A significant decrease in red areas and a borderline significant reduction in the number of wrinkles have been shown by skin aging objective feature calculation on VISIA 2D photographs. OCT analysis showed a borderline significant reduction in collagen density.

CONCLUSIONS

The decrease in vascular pattern and collagen density suggests an anti-inflammatory effect with a potential stromal remodeling in the treated group. This seems to be correlated to the reduction in wrinkles and facial redness.

Beneficial effects of fenoprofen on cognitive impairment induced by the kindling model of epilepsy: Interaction of oxidative stress and inflammation

Hippocampal-dependent cognitive impairments are consequences of temporal lobe epilepsy. This study aimed to assess the modulatory effects of fenoprofen on Pentylenetetrazol (PTZ)-induced cognitive dysfunction in the rat model of epilepsy. Male Wistar rats were randomly divided into five groups. Except for the control group, the kindling model was induced by intraperitoneal (IP) injection of PTZ (35 mg/kg) every other day for a month. Three groups received fenoprofen (10, 20, and 40 mg/kg) before each PTZ injection. One week after kindling development, rats were challenged with PTZ (70 mg/kg). The Morris Water Maze, Shuttle Box, and Elevated Plus Maze tests were applied to assess cognitive functions. Rats' serum and brain samples were prepared for biochemical, histological, and gene expression studies. Fenoprofen pretreatment effectively reduced the mean seizure score, and treated rats had better cognitive performance than the PTZ group in passive avoidance and spatial memory and learning tests; they also showed less anxiety-like behaviors. Its administration also showed anti-oxidative properties. So the serum level of Nitric oxide was significantly reduced while Glutathione and Catalase increased significantly. It also diminished the expression of inflammatory genes (Tumor Necrosis Factor alpha (TNF-α) and Nuclear Factor Kappa B (NF-kB)) in the hippocampus, these results were confirmed by histological observation from Hematoxylin & Eosin staining. These results show the ability of fenoprofen to reduce cognitive impairments caused by epilepsy induction. These effects seem to be through the modulation of inflammatory mediators and oxidative stress.

Glucagon-like peptide-1 receptor: mechanisms and advances in therapy

The glucagon-like peptide-1 (GLP-1) receptor, known as GLP-1R, is a vital component of the G protein-coupled receptor (GPCR) family and is found primarily on the surfaces of various cell types within the human body. This receptor specifically interacts with GLP-1, a key hormone that plays an integral role in regulating blood glucose levels, lipid metabolism, and several other crucial biological functions. In recent years, GLP-1 medications have become a focal point in the medical community due to their innovative treatment mechanisms, significant therapeutic efficacy, and broad development prospects. This article thoroughly traces the developmental milestones of GLP-1 drugs, from their initial discovery to their clinical application, detailing the evolution of diverse GLP-1 medications along with their distinct pharmacological properties. Additionally, this paper explores the potential applications of GLP-1 receptor agonists (GLP-1RAs) in fields such as neuroprotection, anti-infection measures, the reduction of various types of inflammation, and the enhancement of cardiovascular function. It provides an in-depth assessment of the effectiveness of GLP-1RAs across multiple body systems-including the nervous, cardiovascular, musculoskeletal, and digestive systems. This includes integrating the latest clinical trial data and delving into potential signaling pathways and pharmacological mechanisms. The primary goal of this article is to emphasize the extensive benefits of using GLP-1RAs in treating a broad spectrum of diseases, such as obesity, cardiovascular diseases, non-alcoholic fatty liver disease (NAFLD), neurodegenerative diseases, musculoskeletal inflammation, and various forms of cancer. The ongoing development of new indications for GLP-1 drugs offers promising prospects for further expanding therapeutic interventions, showcasing their significant potential in the medical field.

Tisochrysis lutea Fucoxanthin Suppresses NF-κB, JNK, and p38-Associated MMP Expression in Arthritis Pathogenesis via Antioxidant Activity

Tisochrysis lutea is a highly nutritious marine microalga that has various applications in aquaculture and biotechnology. However, the effects of T. lutea extract (TLE) on osteoarthritis (OA) pathogenesis remain unexplored. In this study, we aimed to determine the effects of TLE on OA development. We found that TLE inhibits the expression of matrix metalloproteinases (MMPs) and reactive oxygen species (ROS) activity in an OA mouse model generated by the destabilization of the medial meniscus (DMM) surgery. In vivo assays of the OA model mice demonstrated that TLE has a protective effect against cartilage destruction by inhibiting MMP3 and MMP13 expression. To enable the medical use of TLE, the components of TLE were characterized using high-performance liquid chromatography (HPLC) analysis. Interestingly, we found that Fucoxanthin accounts for 41.2% of TLE and showed anti-catabolic and antioxidant effects under IL-1β-treated in vitro conditions. RNA sequencing analysis showed that fucoxanthin decreased p38, NF-κB, and JNK signaling pathway gene expression, all of which are activated by IL-1β. Furthermore, in vivo analysis showed that fucoxanthin inhibited the IL-1β-stimulated phosphorylation of p65, JNK, and p38. These results highlight new possibilities for the use of TLE as a source of fucoxanthin, an antioxidant, for OA treatment.

Neuromodulatory Effects Induced by the Association of Moringa oleifera Lam., Tribulus terrestris L., Rhodiola rosea Lam., and Undaria pinnatidifida Extracts in the Hypothalamus

The present study investigated the role of a commercial formulation constituted by herbal extracts from Rhodiola rosea, Undaria pinnatifida, Tribulus terrestris, and Moringa oleifera. The formulation was analysed for determining the content in total phenols and flavonoids and scavenging/reducing properties. The formulation was also tested on isolated mouse hypothalamus in order to investigate effects on serotonin, dopamine, neuropeptide Y (NPY), and orexin A. The gene expression of gonadrotopin releasing hormone (GnRH) was also assayed. The formulation was able to reduce dopamine and serotonin turnover, and this could be related, albeit partially, to the capability of different phytochemicals, among which hyperoside and catechin to inhibit monoaminooxidases activity. In parallel, the formulation was effective in reducing the gene expression of NPY and orexin-A and to improve the gene expression of GnRH. In this context, the increased GnRH gene expression induced by the formulation may contribute not only to improve the resistance towards the stress related to ageing, but also to prevent the reduction of libido that could be related with a stimulation of the serotoninergic pathway. According to the in silico analysis, hyperoside could play a pivotal role in modulating the gene expression of GnRH. Regarding NPY and orexin A gene expression, no direct interactions between the formulation phytochemicals and these neuropeptides were anticipated; thus, suggesting that the pattern of gene expression observed following exposure of the hypothalamus to the formulation may be secondary to inhibitory effects of dopamine and serotonin turnover. Concluding, the present study demonstrated the efficacy of the formulation in exerting neuromodulatory effects at the hypothalamic level; thus, suggesting the potential to contrast stress and fatigue.

Dose-Dependent Effects of Lipopolysaccharide on the Endothelium-Sepsis versus Metabolic Endotoxemia-Induced Cellular Senescence

The endothelium, the innermost cell layer of blood vessels, is not only a physical barrier between the bloodstream and the surrounding tissues but has also essential functions in vascular homeostasis. Therefore, it is not surprising that endothelial dysfunction is associated with most cardiovascular diseases. The functionality of the endothelium is compromised by endotoxemia, the presence of bacterial endotoxins in the bloodstream with the main endotoxin lipopolysaccharide (LPS). Therefore, this review will focus on the effects of LPS on the endothelium. Depending on the LPS concentration, the outcomes are either sepsis or, at lower concentrations, so-called low-dose or metabolic endotoxemia. Sepsis, a life-threatening condition evoked by hyperactivation of the immune response, includes breakdown of the endothelial barrier resulting in failure of multiple organs. A deeper understanding of the underlying mechanisms in the endothelium might help pave the way to new therapeutic options in sepsis treatment to prevent endothelial leakage and fatal septic shock. Low-dose endotoxemia or metabolic endotoxemia results in chronic inflammation leading to endothelial cell senescence, which entails endothelial dysfunction and thus plays a critical role in cardiovascular diseases. The identification of compounds counteracting senescence induction in endothelial cells might therefore help in delaying the onset or progression of age-related pathologies. Interestingly, two natural plant-derived substances, caffeine and curcumin, have shown potential in preventing endothelial cell senescence.

Understanding Macroalgae: A Comprehensive Exploration of Nutraceutical, Pharmaceutical, and Omics Dimensions

Driven by a surge in global interest in natural products, macroalgae or seaweed, has emerged as a prime source for nutraceuticals and pharmaceutical applications. Characterized by remarkable genetic diversity and a crucial role in marine ecosystems, these organisms offer not only substantial nutritional value in proteins, fibers, vitamins, and minerals, but also a diverse array of bioactive molecules with promising pharmaceutical properties. Furthermore, macroalgae produce approximately 80% of the oxygen in the atmosphere, highlighting their ecological significance. The unique combination of nutritional and bioactive attributes positions macroalgae as an ideal resource for food and medicine in various regions worldwide. This comprehensive review consolidates the latest advancements in the field, elucidating the potential applications of macroalgae in developing nutraceuticals and therapeutics. The review emphasizes the pivotal role of omics approaches in deepening our understanding of macroalgae's physiological and molecular characteristics. By highlighting the importance of omics, this review also advocates for continued exploration and utilization of these extraordinary marine organisms in diverse domains, including drug discovery, functional foods, and other industrial applications. The multifaceted potential of macroalgae warrants further research and development to unlock their full benefits and contribute to advancing global health and sustainable industries.

Identification of Anti-Neuroinflammatory Bioactive Compounds in Essential Oils and Aqueous Distillation Residues Obtained from Commercial Varieties of Cannabis sativa L

Neuroinflammation, which is mainly triggered by microglia, is a key contributor to multiple neurodegenerative diseases. Natural products, and in particular Cannabis sativa L., due to its richness in phytochemical components, represent ideal candidates to counteract neuroinflammation. We previously characterized different C. sativa commercial varieties which showed significantly different chemical profiles. On these bases, the aim of this study was to evaluate essential oils and aqueous distillation residues from the inflorescences of three different hemp varieties for their anti-neuroinflammatory activity in BV-2 microglial cells. Cells were pretreated with aqueous residues or essential oils and then activated with LPS. Unlike essential oils, aqueous residues showed negligible effects in terms of anti-inflammatory activity. Among the essential oils, the one obtained from 'Gorilla Glue' was the most effective in inhibiting pro-inflammatory mediators and in upregulating anti-inflammatory ones through the modulation of the p38 MAPK/NF-κB pathway. Moreover, the sesquiterpenes (E)-caryophyllene, α-humulene, and caryophyllene oxide were identified as the main contributors to the essential oils' anti-inflammatory activity. To our knowledge, the anti-neuroinflammatory activity of α-humulene has not been previously described. In conclusion, our work shows that C. sativa essential oils characterized by high levels of sesquiterpenes can be promising candidates in the prevention/counteraction of neuroinflammation.

Prevention of aspirin-mediated secondary toxicity by combined treatment of carotenoids in macrophages

Upon understanding the boosting role of carotenoids on the endogenous anti-inflammatory system, it is vital to explore their role in reducing the use of high doses of non-steroidal anti-inflammatory drug (NSAIDs), and their mediated secondary toxicity during the treatment of chronic diseases. The current study investigates the carotenoids potential on inhibition of secondary complications induced by NSAIDs, aspirin (ASA) against lipopolysaccharide (LPS) stimulated inflammation. Initially, this study evaluated a minimal cytotoxic dose of ASA and carotenoids (β-carotene, BC/lutein, LUT/astaxanthin, AST/fucoxanthin FUCO) in Raw 264.7, U937, and peripheral blood mononuclear cells (PBMCs). In all three cells, carotenoids + ASA treatment reduced the LDH release, NO, and PGE2 efficiently than an equivalent dose of carotenoid or ASA treated alone. Based on cytotoxicity and sensitivity results, RAW 264.7 cells were selected for further cell-based assay. Among carotenoids, FUCO + ASA exhibited an efficient reduction of LDH release, NO, and PGE2 than the other carotenoids (BC + ASA, LUT + ASA, and AST + ASA) treatment. FUCO + ASA combination decreased LPS/ASA induced oxidative stress, pro-inflammatory mediators (iNOS, COX-2, and NF-κB), and cytokines (IL-6, TNF-α, and IL-1β) efficiently. Further, apoptosis was inhibited by 69.2% in FUCO + ASA, and 46.7% in ASA than LPS treated cells. A drastic decrease in intracellular ROS generation with the increase in GSH was observed in FUCO + ASA compared to LPS/ASA groups. The results documented on the low dose of ASA with a relative physiological concentration of FUCO suggested greater importance for alleviating secondary complications and optimize prolonged chronic disease treatments with NSAID's associated side effects.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03632-w.

SENP3-mediated deSUMOylation of c-Jun facilitates microglia-induced neuroinflammation after cerebral ischemia and reperfusion injury

Recent evidences have implicated that SENP3 is a deSUMOylase which possesses neuronal damage effects in cerebral ischemia. However, its role in microglia remains poorly understood. Here, we found that SENP3 was upregulated in the peri-infarct areas of mice following ischemic stroke. Furthermore, knockdown of SENP3 significantly inhibits the expression of proinflammatory cytokines and chemokines in microglial cells. Mechanistically, SENP3 can bind and then mediated the deSUMOylation of c-Jun, which activated its transcriptional activity, ultimately followed by the activation of MAPK/AP-1 signaling pathway. In addition, microglia-specific SENP3 knockdown alleviated ischemia-induced neuronal damage, and markedly diminished infract volume, ameliorated sensorimotor and cognitive function in animals subjected to ischemic stroke. These results indicated SENP3 functions as a novel regulator of microglia-induced neuroinflammation by activating the MAPK/AP-1 signaling pathway via mediating the deSUMOylation of c-Jun. Interventions of SENP3 expression or its interaction with c-Jun would be a new and promising therapeutic strategy for ischemic stroke.

Dietary Protective Potential of Fucoxanthin as an Active Food Component on Neurological Disorders

The prevalence of neurodegenerative, cerebrovascular, and psychiatric diseases and other neurological disorders has increased dramatically worldwide. Fucoxanthin is an algal pigment with many biological functions, and there is rising evidence that fucoxanthin plays a preventive and therapeutic role in neurological disorders. This review focuses on the metabolism, bioavailability, and blood-brain barrier penetration of fucoxanthin. Furthermore, the neuroprotective potential of fucoxanthin in neurodegenerative diseases, cerebrovascular diseases, and psychiatric diseases as well as other neurological disorders such as epilepsy, neuropathic pain, and brain tumors by acting on multiple targets will be summarized. The multiple targets include regulating apoptosis, reducing oxidative stress, activating the autophagy pathway, inhibiting Aβ aggregation, improving dopamine secretion, reducing α-synuclein aggregation, attenuating neuroinflammation, modulating gut microbiota, and activating brain-derived neurotrophic factor, etc. Additionally, we look forward to brain-targeted oral transport systems due to the low bioavailability and blood-brain barrier permeability of fucoxanthin. We also propose exploring the systemic mechanisms of fucoxanthin metabolism and transport through the gut-brain process and envision new therapeutic targets for fucoxanthin to act on the central nervous system. Finally, we propose dietary fucoxanthin delivery interventions to achieve preventive effects on neurological disorders. This review provides a reference for the application of fucoxanthin in the neural field.

Preparation and properties of fucoxanthin-loaded liposomes stabilized by sea cucumber derived cholesterol sulfate instead of cholesterol

The preparation of steady-state phospholipid liposomes requires cholesterol as a stabilizer, but excessive intake of cholesterol may increase the risk of cardiovascular disease. The sulfated sterols extracted from sea cucumber, mainly including sulfated 24-methylene cholesterol and cholesterol sulfate, have been reported to have a variety of physiological activities. Sulfated sterols are similar to cholesterol in structure and have the potential to replace cholesterol to prepare novel stable multifunctional liposomes, allowing the liposomes to act as carriers for the delivery of less bioavailable nutrients while allowing sulfated sterols in the lipid bilayer to exert physiologically active effects. This study aimed to prepare a novel multifunctional nanoliposome stabilized with sulfated sterols from sea cucumber instead of cholesterol by ultrasound-assisted thin-film dispersion method. The results showed that stable and uniformly dispersed nanoliposomes could be formed when the substitution ratio of sea cucumber-derived cholesterol sulfate was 100% and the ratio of lecithin to cholesterol sulfate was 3:1. Fucoxanthin encapsulated liposome with egg yolk lecithin/sea cucumber-derived cholesterol sulfate/fucoxanthin mass ratio of 6:2:3 was successfully prepared, with an average particle size of 214 ± 3 nm, polydispersity index (PDI) value of 0.297 ± 0.006, the zeta potential of -57.2 ± 1.10 mV, and the encapsulation efficiency of 85.5 ± 0.8%. The results of digestion and absorption in vitro and in vivo showed that liposomes could significantly improve the bioavailability of fucoxanthin and prolong its residence time in serum. As an efficient multifunctional carrier, this novel liposome has great potential for applications in functional foods and biomedicine.

Anti-Inflammatory Effects of Marine Bioactive Compounds and Their Potential as Functional Food Ingredients in the Prevention and Treatment of Neuroinflammatory Disorders

Functional foods include enhanced, enriched, fortified, or whole foods that impart health benefits beyond their nutritional value, particularly when consumed as part of a varied diet on a regular basis at effective levels. Marine sources can serve as the sources of various healthy foods and numerous functional food ingredients with biological effects can be derived from these sources. Microalgae, macroalgae, crustaceans, fungi, bacteria fish, and fish by-products are the most common marine sources that can provide many potential functional food ingredients including phenolic compounds, proteins and peptides, and polysaccharides. Neuroinflammation is closely linked with the initiation and progression of various neurodegenerative diseases, including Alzheimer's disease, Huntington's disease, and Parkinson's disease. Activation of astrocytes and microglia is a defense mechanism of the brain to counter damaged tissues and detrimental pathogens, wherein their chronic activation triggers neuroinflammation that can further exacerbate or induce neurodegeneration. Currently, available therapeutic agents only provide symptomatic relief from these disorders and no therapies are available to stop or slow down the advancement of neurodegeneration. Thereffore, natural compounds that can exert a protective effect against these disorders have therapeutic potential. Numerous chemical compounds, including bioactive peptides, fatty acids, pigments, alkaloids, and polysaccharides, have already been isolated from marine sources that show anti-inflammatory properties, which can be effective in the treatment and prevention of neuroinflammatory disorders. The anti-inflammatory potential of marine-derived compounds as functional food ingredients in the prevention and treatment of neurological disorders is covered in this review.

Macroalgae Specialized Metabolites: Evidence for Their Anti-Inflammatory Health Benefits

Inflammation is an organism's response to chemical or physical injury. It is split into acute and chronic inflammation and is the last, most significant cause of death worldwide. Nowadays, according to the World Health Organization (WHO), the greatest threat to human health is chronic disease. Worldwide, three out of five people die from chronic inflammatory diseases such as stroke, chronic respiratory diseases, heart disorders, and cancer. Nowadays, anti-inflammatory drugs (steroidal and non-steroidal, enzyme inhibitors that are essential in the inflammatory process, and receptor antagonists, among others) have been considered as promising treatments to be explored. However, there remains a significant proportion of patients who show poor or incomplete responses to these treatments or experience associated severe side effects. Seaweeds represent a valuable resource of bioactive compounds associated with anti-inflammatory effects and offer great potential for the development of new anti-inflammatory drugs. This review presents an overview of specialized metabolites isolated from seaweeds with in situ and in vivo anti-inflammatory properties. Phlorotannins, carotenoids, sterols, alkaloids, and polyunsaturated fatty acids present significant anti-inflammatory effects given that some of them are involved directly or indirectly in several inflammatory pathways. The majority of the isolated compounds inhibit the pro-inflammatory mediators/cytokines. Studies have suggested an excellent selectivity of chromene nucleus towards inducible pro-inflammatory COX-2 than its constitutive isoform COX-1. Additional research is needed to understand the mechanisms of action of seaweed's compounds in inflammation, given the production of sustainable and healthier anti-inflammatory agents.

Antidepressive Effect of Natural Products and Their Derivatives Targeting BDNF-TrkB in Gut-Brain Axis

Modern neurological approaches enable detailed studies on the pathophysiology and treatment of depression. An imbalance in the microbiota-gut-brain axis contributes to the pathogenesis of depression. This extensive review aimed to elucidate the antidepressive effects of brain-derived neurotrophic factor (BDNF)-targeting therapeutic natural products and their derivatives on the gut-brain axis. This information could facilitate the development of novel antidepressant drugs. BDNF is crucial for neuronal genesis, growth, differentiation, survival, plasticity, and synaptic transmission. Signaling via BDNF and its receptor tropomyosin receptor kinase B (TrkB) plays a vital role in the etiopathogenesis of depression and the therapeutic mechanism of antidepressants. This comprehensive review provides information to researchers and scientists for the identification of novel therapeutic approaches for neuropsychiatric disorders, especially depression and stress. Future research should aim to determine the possible causative role of BDNF-TrkB in the gut-brain axis in depression, which will require further animal and clinical research as well as the development of analytical approaches.

Spirulina platensis Suppressed iNOS and Proinflammatory Cytokines in Lipopolysaccharide-Induced BV2 Microglia

The disease burden of neurodegenerative diseases is on the rise due to the aging population, and neuroinflammation is one of the underlying causes. Spirulina platensis is a well-known superfood with numerous reported bioactivities. However, the effect of S. platensis Universiti Malaya Algae Culture Collection 159 (UMACC 159) (a strain isolated from Israel) on proinflammatory mediators and cytokines remains unknown. In this study, we aimed to determine the anti-neuroinflammatory activity of S. platensis extracts and identify the potential bioactive compounds. S. platensis extracts (hexane, ethyl acetate, ethanol, and aqueous) were screened for phytochemical content and antioxidant activity. Ethanol extract was studied for its effect on proinflammatory mediators and cytokines in lipopolysaccharide (LPS)-induced BV2 microglia. The potential bioactive compounds were identified using liquid chromatography-mass spectrometric (LC-MS) analysis. Ethanol extract had the highest flavonoid content and antioxidant and nitric oxide (NO) inhibitory activity. Ethanol extract completely inhibited the production of NO via the downregulation of inducible NO synthase (iNOS) and significantly reduced the production of tumor necrosis factor (TNF)-α and interleukin (IL)-6. Emmotin A, palmitic amide, and 1-monopalmitin, which might play an important role in cell signaling, have been identified. In conclusion, S. platensis ethanol extract inhibited neuroinflammation through the downregulation of NO, TNF-α and IL-6. This preliminary study provided insight into compound(s) isolation, which could contribute to the development of precision nutrition for disease management.

Marine Natural Products from the Russian Pacific as Sources of Drugs for Neurodegenerative Diseases

Neurodegenerative diseases are growing to become one of humanity's biggest health problems, given the number of individuals affected by them. They cause enough mortalities and severe economic impact to rival cancers and infections. With the current diversity of pathophysiological mechanisms involved in neurodegenerative diseases, on the one hand, and scarcity of efficient prevention and treatment strategies, on the other, all possible sources for novel drug discovery must be employed. Marine pharmacology represents a relatively uncharted territory to seek promising compounds, despite the enormous chemodiversity it offers. The current work discusses one vast marine region-the Northwestern or Russian Pacific-as the treasure chest for marine-based drug discovery targeting neurodegenerative diseases. We overview the natural products of neurological properties already discovered from its waters and survey the existing molecular and cellular targets for pharmacological modulation of the disease. We further provide a general assessment of the drug discovery potential of the Russian Pacific in case of its systematic development to tackle neurodegenerative diseases.

Fucoxanthin decreases lipopolysaccharide-induced acute lung injury through the inhibition of RhoA activation and the NF-κB pathway

Fucoxanthin is a natural pigment widely distributed in macroalgae and microalgae. An orange-colored xanthophyll, it has several bioactive effects, including anticancer, anti-obesity, oxidative stress reduction, and anti-inflammation. Acute lung injury (ALI) caused by acute infections or injurious stimuli to the lung tissues is a severe pulmonary inflammatory disease. To date, no evidence has shown ALI to be reduced by fucoxanthin through activation of Ras homolog family member A (RhoA) and the nuclear factor (NF)-κB pathway in lipopolysaccharide (LPS)-treated mice. Pretreatment with fucoxanthin inhibited histopathological changes in lung tissues and neutrophil infiltration into bronchoalveolar lavage fluid induced by LPS in ALI mice. Moreover, LPS-induced proinflammatory cytokine expression and neutrophil infiltration were inhibited by fucoxanthin in a concentration-dependent manner. Pretreatment of mice with fucoxanthin inhibited NF-κB phosphorylation and IκB degradation in the lungs of mice with LPS-induced ALI. We further found that phosphorylation of Akt and p38 mitogen-activated protein KINASE (MAPK) was inhibited by fucoxanthin. By contrast, the phosphorylation of extracellular signal-regulated kinase and c-Jun N-terminal kinase was not inhibited by fucoxanthin. Furthermore, we found that the activation of RhoA was inhibited by fucoxanthin in LPS-induced ALI. On the basis of these results, we propose that fucoxanthin disrupts the RhoA activation-mediated phosphorylation of Akt and p38 MAPK, leading to NF-κB activation in mice with LPS-induced ALI.

Fucoxanthin: A Promising Phytochemical on Diverse Pharmacological Targets

Fucoxanthin (FX) is a special carotenoid having an allenic bond in its structure. FX is extracted from a variety of algae and edible seaweeds. It has been proved to contain numerous health benefits and preventive effects against diseases like diabetes, obesity, liver cirrhosis, malignant cancer, etc. Thus, FX can be used as a potent source of both pharmacological and nutritional ingredient to prevent infectious diseases. In this review, we gathered the information regarding the current findings on antimicrobial, antioxidant, anti-inflammatory, skin protective, anti-obesity, antidiabetic, hepatoprotective, and other properties of FX including its bioavailability and stability characteristics. This review aims to assist further biochemical studies in order to develop further pharmaceutical assets and nutritional products in combination with FX and its various metabolites.

Brown Algae as Functional Food Source of Fucoxanthin: A Review

Fucoxanthin is an algae-specific xanthophyll of aquatic carotenoid. It is prevalent in brown seaweed because it functions as a light-harvesting complex for algal photosynthesis and photoprotection. Its exceptional chemical structure exhibits numerous biological activities that benefit human health. Due to these valuable properties, fucoxanthin's potential as a potent source for functional food, feed, and medicine is being explored extensively today. This article has thoroughly reviewed the availability and biosynthesis of fucoxanthin in the brown seaweed, as well as the mechanism behind it. We included the literature findings concerning the beneficial bioactivities of fucoxanthin such as antioxidant, anti-inflammatory, anti-obesity, antidiabetic, anticancer, and other potential activities. Last, an additional view on its potential as a functional food ingredient has been discussed to facilitate a broader application of fucoxanthin as a promising bioactive compound.

Biological Potential, Gastrointestinal Digestion, Absorption, and Bioavailability of Algae-Derived Compounds with Neuroprotective Activity: A Comprehensive Review

Currently, there is no known cure for neurodegenerative disease. However, the available therapies aim to manage some of the symptoms of the disease. Human neurodegenerative diseases are a heterogeneous group of illnesses characterized by progressive loss of neuronal cells and nervous system dysfunction related to several mechanisms such as protein aggregation, neuroinflammation, oxidative stress, and neurotransmission dysfunction. Neuroprotective compounds are essential in the prevention and management of neurodegenerative diseases. This review will focus on the neurodegeneration mechanisms and the compounds (proteins, polyunsaturated fatty acids (PUFAs), polysaccharides, carotenoids, phycobiliproteins, phenolic compounds, among others) present in seaweeds that have shown in vivo and in vitro neuroprotective activity. Additionally, it will cover the recent findings on the neuroprotective effects of bioactive compounds from macroalgae, with a focus on their biological potential and possible mechanism of action, including microbiota modulation. Furthermore, gastrointestinal digestion, absorption, and bioavailability will be discussed. Moreover, the clinical trials using seaweed-based drugs or extracts to treat neurodegenerative disorders will be presented, showing the real potential and limitations that a specific metabolite or extract may have as a new therapeutic agent considering the recent approval of a seaweed-based drug to treat Alzheimer’s disease.

Natural Products from Plants and Algae for Treatment of Alzheimer’s Disease: A Review

Neurodegenerative disorders including Parkinson’s disease (PD), Huntington’s disease (HD) and the most frequent, Alzheimer’s disease (AD), represent one of the most urgent medical needs worldwide. Despite a significantly developed understanding of disease development and pathology, treatments that stop AD progression are not yet available. The recent approval of sodium oligomannate (GV-971) for AD treatment in China emphasized the potential value of natural products for the treatment of neurodegenerative disorders. Many current clinical studies include the administration of a natural compound as a single and combination treatment. The most prominent mechanisms of action are anti-inflammatory and anti-oxidative activities, thus preserving cellular survival. Here, we review current natural products that are either approved or are in testing for a treatment of neurodegeneration in AD. In addition to the most important compounds of plant origin, we also put special emphasis on compounds from algae, given their neuroprotective activity and their underlying mechanisms of neuroprotection.

A Systematic Review on Marine Algae-Derived Fucoxanthin: An Update of Pharmacological Insights

Fucoxanthin, belonging to the xanthophyll class of carotenoids, is a natural antioxidant pigment of marine algae, including brown macroalgae and diatoms. It represents 10% of the total carotenoids in nature. The plethora of scientific evidence supports the potential benefits of nutraceutical and pharmaceutical uses of fucoxanthin for boosting human health and disease management. Due to its unique chemical structure and action as a single compound with multi-targets of health effects, it has attracted mounting attention from the scientific community, resulting in an escalated number of scientific publications from January 2017 to February 2022. Fucoxanthin has remained the most popular option for anti-cancer and anti-tumor activity, followed by protection against inflammatory, oxidative stress-related, nervous system, obesity, hepatic, diabetic, kidney, cardiac, skin, respiratory and microbial diseases, in a variety of model systems. Despite much pharmacological evidence from in vitro and in vivo findings, fucoxanthin in clinical research is still not satisfactory, because only one clinical study on obesity management was reported in the last five years. Additionally, pharmacokinetics, safety, toxicity, functional stability, and clinical perspective of fucoxanthin are substantially addressed. Nevertheless, fucoxanthin and its derivatives are shown to be safe, non-toxic, and readily available upon administration. This review will provide pharmacological insights into fucoxanthin, underlying the diverse molecular mechanisms of health benefits. However, it requires more activity-oriented translational research in humans before it can be used as a multi-target drug.

Targeting Nrf2-Mediated Oxidative Stress Response in Traumatic Brain Injury: Therapeutic Perspectives of Phytochemicals

Traumatic brain injury (TBI), known as mechanical damage to the brain, impairs the normal function of the brain seriously. Its clinical symptoms manifest as behavioral impairment, cognitive decline, communication difficulties, etc. The pathophysiological mechanisms of TBI are complex and involve inflammatory response, oxidative stress, mitochondrial dysfunction, blood-brain barrier (BBB) disruption, and so on. Among them, oxidative stress, one of the important mechanisms, occurs at the beginning and accompanies the whole process of TBI. Most importantly, excessive oxidative stress causes BBB disruption and brings injury to lipids, proteins, and DNA, leading to the generation of lipid peroxidation, damage of nuclear and mitochondrial DNA, neuronal apoptosis, and neuroinflammatory response. Transcription factor NF-E2 related factor 2 (Nrf2), a basic leucine zipper protein, plays an important role in the regulation of antioxidant proteins, such as oxygenase-1(HO-1), NAD(P)H Quinone Dehydrogenase 1 (NQO1), and glutathione peroxidase (GPx), to protect against oxidative stress, neuroinflammation, and neuronal apoptosis. Recently, emerging evidence indicated the knockout (KO) of Nrf2 aggravates the pathology of TBI, while the treatment of Nrf2 activators inhibits neuronal apoptosis and neuroinflammatory responses via reducing oxidative damage. Phytochemicals from fruits, vegetables, grains, and other medical herbs have been demonstrated to activate the Nrf2 signaling pathway and exert neuroprotective effects in TBI. In this review, we emphasized the contributive role of oxidative stress in the pathology of TBI and the protective mechanism of the Nrf2-mediated oxidative stress response for the treatment of TBI. In addition, we summarized the research advances of phytochemicals, including polyphenols, terpenoids, natural pigments, and otherwise, in the activation of Nrf2 signaling and their potential therapies for TBI. Although there is still limited clinical application evidence for these natural Nrf2 activators, we believe that the combinational use of phytochemicals such as Nrf2 activators with gene and stem cell therapy will be a promising therapeutic strategy for TBI in the future.

Carotenoids from Marine Sources as a New Approach in Neuroplasticity Enhancement

An increasing number of people experience disorders related to the central nervous system (CNS). Thus, new forms of therapy, which may be helpful in repairing processes' enhancement and restoring declined brain functions, are constantly being sought. One of the most relevant physiological processes occurring in the brain for its entire life is neuroplasticity. It has tremendous significance concerning CNS disorders since neurological recovery mainly depends on restoring its structural and functional organization. The main factors contributing to nerve tissue damage are oxidative stress and inflammation. Hence, marine carotenoids, abundantly occurring in the aquatic environment, being potent antioxidant compounds, may play a pivotal role in nerve cell protection. Furthermore, recent results revealed another valuable characteristic of these compounds in CNS therapy. By inhibiting oxidative stress and neuroinflammation, carotenoids promote synaptogenesis and neurogenesis, consequently presenting neuroprotective activity. Therefore, this paper focuses on the carotenoids obtained from marine sources and their impact on neuroplasticity enhancement.

Therapeutic promise of carotenoids as antioxidants and anti-inflammatory agents in neurodegenerative disorders

Neurodegenerative disorders (NDs) including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, Huntington's disease, and multiple sclerosis have various disease-specific causal factors and pathological features. A very common characteristic of NDs is oxidative stress (OS), which takes place due to the elevated generation of reactive oxygen species during the progression of NDs. Furthermore, the pathological condition of NDs including an increased level of protein aggregates can further lead to chronic inflammation because of the microglial activation. Carotenoids (CTs) are naturally occurring pigments that play a significant role in averting brain disorders. More than 750 CTs are present in nature, and they are widely available in plants, microorganisms, and animals. CTs are accountable for the red, yellow, and orange pigments in several animals and plants, and these colors usually indicate various types of CTs. CTs exert various bioactive properties because of its characteristic structure, including anti-inflammatory and antioxidant properties. Due to the protective properties of CTs, levels of CTs in the human body have been markedly linked with the prevention and treatment of multiple diseases including NDs. In this review, we have summarized the relationship between OS, neuroinflammation, and NDs. In addition, we have also particularly focused on the antioxidants and anti-inflammatory properties of CTs in the management of NDs.

Anti-Inflammatory and Anticancer Effects of Microalgal Carotenoids

Acute inflammation is a key component of the immune system's response to pathogens, toxic agents, or tissue injury, involving the stimulation of defense mechanisms aimed to removing pathogenic factors and restoring tissue homeostasis. However, uncontrolled acute inflammatory response may lead to chronic inflammation, which is involved in the development of many diseases, including cancer. Nowadays, the need to find new potential therapeutic compounds has raised the worldwide scientific interest to study the marine environment. Specifically, microalgae are considered rich sources of bioactive molecules, such as carotenoids, which are natural isoprenoid pigments with important beneficial effects for health due to their biological activities. Carotenoids are essential nutrients for mammals, but they are unable to synthesize them; instead, a dietary intake of these compounds is required. Carotenoids are classified as carotenes (hydrocarbon carotenoids), such as α- and β-carotene, and xanthophylls (oxygenate derivatives) including zeaxanthin, astaxanthin, fucoxanthin, lutein, α- and β-cryptoxanthin, and canthaxanthin. This review summarizes the present up-to-date knowledge of the anti-inflammatory and anticancer activities of microalgal carotenoids both in vitro and in vivo, as well as the latest status of human studies for their potential use in prevention and treatment of inflammatory diseases and cancer.

Nutritional Supplements and Neuroprotective Diets and Their Potential Clinical Significance in Post-Stroke Rehabilitation

Nutrition and rehabilitation are crucial in post-stroke recovery, especially in the elderly. Since stroke is the leading cause of long-term disability, there is a need to promote special, individually tailored nutrition strategies targeting older patients with low motor ability. Chronic stroke survivors have higher risk of developing nutrition-related chronic diseases, such as sarcopenia, anemia, type 2 diabetes mellitus and osteoporosis. Moreover, reduced motor activity, cognitive impairment and depression might be aggravated by poor malnutrition status. Accumulated data suggest that nutritional supplements and neuroprotective diets can be associated with better effectiveness of post-stroke rehabilitation as well as brain recovery. Therefore, this review focuses on preventive strategies that can improve dietary intake and change dietary patterns. We highlight the importance of neuroprotective diets, the problem of dysphagia and the role of nutrition in rehabilitation. This article focuses on potential nutritional supplements and neuroprotective diets that may have an impact on functional recovery during and after rehabilitation. Moreover, a new approach to post-stroke neuroplasticity including the use of agents from marine sources such as fucoxanthin and tramiprosate as compounds that might be used as potential neuroprotectants with antioxidative and anti-inflammatory properties is introduced.

(-)-Syringaresinol suppressed LPS-induced microglia activation via downregulation of NF-κB p65 signaling and interaction with ERβ

Albiziae Cortex (AC) is a well-known traditional Chinese medicine with sedative-hypnotic effects and neuroprotective ability. However, the bioactive components of AC responsible for the neuro-protective actitivity remain unknown. Here, we investigated the anti-neuroinflammatory effects of (-)-syringaresinol (SYR) extracted from AC in microglia cells and wild-type mice. As a result, (-)-SYR significantly reduced lipopolysaccharide (LPS)-induced production of interleukin - 6 (IL-6), tumor necrosis factor α (TNF-α), interleukin -1 beta (IL-1β), cycloxygenase-2 (COX-2), and nitric oxide (NO) in BV2 microglia cells. (-)-SYR also significantly reduced M1 marker CD40 expression and increased M2 marker CD206 expression. Moreover, we found that (-)-SYR inhibited LPS-induced NF-κB activation by suppressing the translocation of NF-κB p65 into the nucleus in a concentration-dependent manner. Meanwhile, estrogen receptor β (ERβ) was found to be implied in the anti-inflammatory activity of (-)-SYR in BV2 microglia. In vivo experiments revealed that administration of (-)-SYR in mice significantly reduced microglia/astrocytes activation and mRNA levels of proinflammatory mediators. Taken together, our data indicated that (-)-SYR exerted the anti-neuroinflammatory effects by inhibiting NF-κB activation and modulation of microglia polarization, and via interaction with ERβ. The anti-neuroinflammatory activity of (-)-SYR may provide a new therapeutic avenue for the treatment of brain diseases associated with inflammation.

Neuroprotective effects of NDEELNK from sea cucumber ovum against scopolamine-induced PC12 cell damage through enhancing energy metabolism and upregulation of the PKA/BDNF/NGF signaling pathway

The aim of the study was to evaluate the neuroprotective function of sea cucumber ovum peptide-derived NDEELNK and explore the underlying molecular mechanisms. NDEELNK exerted the neuroprotective effect by improving the acetylcholine (ACh) level and reducing the acetylcholinesterase (AChE) activity in PC12 cells. By molecular docking, we confirmed that the NDEELNK backbone and AChE interacted through hydrophobic and hydrogen bonds in contact with the amino acid residues of the cavity wall. NDEELNK increased superoxide dismutase (SOD) activity and decreased reactive oxygen species (ROS) production, thereby reducing mitochondrial dysfunction and enhancing energy metabolism. Our results demonstrated that NDEELNK supplementation alleviated scopolamine-induced PC12 cell damage by improving the cholinergic system, increasing energy metabolism and upregulating the expression of phosphorylated protein kinase A (p-PKA), brain-derived neurotrophic factor (BNDF) and nerve growth factor (NGF) signaling proteins in in vitro experiments. These results demonstrated that the sea cucumber ovum peptide-derived NDEELNK might play a protective role in PC12 cells.

The State of The Art on Acetylcholinesterase Inhibitors in the Treatment of Alzheimer's Disease

Alzheimer's disease (AD) is a chronic disabling disease that affects the central nervous system. The main consequences of AD include the decline of cognitive functions and language disorders. One of the causes leading to AD is the decrease of neurotransmitter acetylcholine (ACh) levels in the brain, in part due to a higher activity of acetylcholinesterase (AChE), the enzyme responsible for its degradation. Many acetylcholinesterase inhibitors (AChEIs), both natural and synthetic, have been developed and used through the years to counteract the progression of the disease. The first of such drugs approved for a therapeutic use was tacrine, that binds through a reversible bond to the enzyme. However, tacrine has since been withdrawn because of its adverse effects. Currently, donepezil and galantamine are very promising AChEIs with clinical benefits. Moreover, rivastigmine is considered a pseudo-irreversible compound with anti-AChE action, providing similar effects at the clinical level. The purpose of this review is to provide an overview of what has been published over the last decade on the effectiveness of AChEIs in AD, analysing the most relevant issues under the clinical and methodological profiles and the consequent possible welfare effects for the whole world. Furthermore, novel drugs and possible therapeutic approaches are also discussed.

Ethanol extract of Sargarsum fusiforme alleviates HFD/STZ-induced hyperglycemia in association with modulation of gut microbiota and intestinal metabolites in type 2 diabetic mice

Type 2 diabetes mellitus (T2DM) is considered a rapidly growing chronic disease that threatens human health worldwide. Extracts of various seaweeds have been shown to have anti-diabetic activity. Sargarsum fusiforme, an edible brown seaweed, has been shown to possess anti-inflammatory, anti-diabetic and anti-obesity activities. In this study, we investigated the beneficial effect of an ethanol extract of S. fusiforme (EE) on type 2 diabetes in mice induced with high-fat diet (HFD) and streptozotocin (STZ). Administering EE to the diabetic mice significantly reduced food intake, water intake and fasting blood glucose (FBG), while improving glucose tolerance, lipid profile and ameliorating hepatic oxidative stress. Furthermore, these animals also exhibited significantly diminished epididymal fat deposition, as well as less pathological changes in the heart and liver tissues, while displaying some highly enriched benign gut bacteria (e.g., Intestinimonas, Oscillibacter, Lachnoclostridium, unidentified_Lachnospiraceae, Roseburia and Anaerotruncus) and a lower abundance of bacteria associated with diabetes or other metabolic diseases (e.g., Enterorhabdus and Romboutsia). Metabolomic analysis revealed reduced levels of branched-chain amino acids (BCAA), such as l-valine and l-isoleucine, aromatic amino acids (AAA), such as l-tyrosine and l-phenylalanine, and increased levels of 4-hydroxyphenylacetic acid (4-HPA) in the gut content, suggesting that EE may impact T2DM through modulation of these compounds in the gut of the animals. Taken together, the results implied that S. fusiforme may contain valuable active components other than polysaccharides that have potential benefit in alleviating T2DM.

The endocannabinoidome in neuropsychiatry: Opportunities and potential risks

The endocannabinoid system (ECS) comprises two cognate endocannabinoid receptors referred to as CB1R and CB2R_. ECS dysregulation is apparent in neurodegenerative/neuro-psychiatric disorders including but not limited to schizophrenia, major depressive disorder and potentially bipolar disorder. The aim of this paper is to review mechanisms whereby both receptors may interact with neuro-immune and neuro-oxidative pathways, which play a pathophysiological role in these disorders. CB1R is located in the presynaptic terminals of GABAergic, glutamatergic, cholinergic, noradrenergic and serotonergic neurons where it regulates the retrograde suppression of neurotransmission. CB1R plays a key role in long-term depression, and, to a lesser extent, long-term potentiation, thereby modulating synaptic transmission and mediating learning and memory. Optimal CB1R activity plays an essential neuroprotective role by providing a defense against the development of glutamate-mediated excitotoxicity, which is achieved, at least in part, by impeding AMPA-mediated increase in intracellular calcium overload and oxidative stress. Moreover, CB1R activity enables optimal neuron-glial communication and the function of the neurovascular unit. CB2R receptors are detected in peripheral immune cells and also in central nervous system regions including the striatum, basal ganglia, frontal cortex, hippocampus, amygdala as well as the ventral tegmental area. CB2R upregulation inhibits the presynaptic release of glutamate in several brain regions. CB2R activation also decreases neuroinflammation partly by mediating the transition from a predominantly neurotoxic "M1" microglial phenotype to a more neuroprotective "M2" phenotype. CB1R and CB2R are thus novel drug targets for the treatment of neuro-immune and neuro-oxidative disorders including schizophrenia and affective disorders.

Mechanistic aspects of carotenoid health benefits - where are we now?

Dietary intake and tissue levels of carotenoids have been associated with a reduced risk of several chronic diseases, including cardiovascular diseases, type 2 diabetes, obesity, brain-related diseases and some types of cancer. However, intervention trials with isolated carotenoid supplements have mostly failed to confirm the postulated health benefits. It has thereby been speculated that dosing, matrix and synergistic effects, as well as underlying health and the individual nutritional status plus genetic background do play a role. It appears that our knowledge on carotenoid-mediated health benefits may still be incomplete, as the underlying mechanisms of action are poorly understood in relation to human relevance. Antioxidant mechanisms - direct or via transcription factors such as NRF2 and NF-κB - and activation of nuclear hormone receptor pathways such as of RAR, RXR or also PPARs, via carotenoid metabolites, are the basic principles which we try to connect with carotenoid-transmitted health benefits as exemplified with described common diseases including obesity/diabetes and cancer. Depending on the targeted diseases, single or multiple mechanisms of actions may play a role. In this review and position paper, we try to highlight our present knowledge on carotenoid metabolism and mechanisms translatable into health benefits related to several chronic diseases.

Algae-Derived Anti-Inflammatory Compounds against Particulate Matters-Induced Respiratory Diseases: A Systematic Review

Air pollution has recently become a subject of increasing concern in many parts of the world. The World Health Organization (WHO) estimated that nearly 4.2 million early deaths are due to exposure to fine particles in polluted air, which causes multiple respiratory diseases. Algae, as a natural product, can be an alternative treatment due to potential biofunctional properties and advantages. This systematic review aims to summarize and evaluate the evidence of metabolites derived from algae as potential anti-inflammatory agents against respiratory disorders induced by atmospheric particulate matter (PM). Databases such as Scopus, Web of Science, and PubMed were systematically searched for relevant published full articles from 2016 to 2020. The main key search terms were limited to "algae", "anti-inflammation", and "air pollutant". The search activity resulted in the retrieval of a total of 36 publications. Nine publications are eligible for inclusion in this systematic review. A total of four brown algae (Ecklonia cava, Ishige okamurae, Sargassum binderi and Sargassum horneri) with phytosterol, polysaccharides and polyphenols were reported in the nine studies. The review sheds light on the pathways of particulate matter travelling into respiratory systems and causing inflammation, and on the mechanisms of actions of algae in inhibiting inflammation. Limitations and future directions are also discussed. More research is needed to investigate the potential of algae as anti-inflammatory agents against PM in in vivo and in vitro experimental models, as well as clinically.

Fucoxanthin has potential for therapeutic efficacy in neurodegenerative disorders by acting on multiple targets

Fucoxanthin, one of the most abundant carotenoids from edible brown seaweeds, for years has been used as a bioactive dietary supplement and functional food ingredient. Recently, fucoxanthin was reported to penetrate the blood-brain barrier, and was superior to other carotenoids to exert anti-neurodegenerative disorder effects via acting on multiple targets, including amyloid protein aggregation, oxidative stress, neuroinflammation, neuronal loss, neurotransmission dysregulation and gut microbiota disorder. However, the concentration of fucoxanthin required for in vivo neuroprotective effects is somewhat high, and the poor bioavailability of this molecule might prevent its clinical use. As such, new strategies have been introduced to overcome these obstacles, and may help to develop fucoxanthin as a novel lead for neurodegenerative disorders. Moreover, it has been shown that some metabolites of fucoxanthin may produce potent in vivo neuroprotective effects. Altogether, these studies suggest the possibility for future development of fucoxanthin as a one-compound-multiple-target or pro-drug type pharmaceutical or nutraceutical treatment for neurodegenerative disorders.Trial registration: ClinicalTrials.gov identifier: NCT03625284.Trial registration: ClinicalTrials.gov identifier: NCT02875392.Trial registration: ClinicalTrials.gov identifier: NCT03613740.Trial registration: ClinicalTrials.gov identifier: NCT04761406.

Narciclasine inhibits LPS-induced neuroinflammation by modulating the Akt/IKK/NF-κB and JNK signaling pathways

BACKGROUND

Neuroinflammation is defined as innate immune system activation in the central nervous system, and is a complex response involved in removing pathogens, toxic components, and dead cells by activating microglial cells. However, over-activated microglia have been implicated in the pathogenesis of neurodegenerative diseases, because they release large amounts of neurotoxic factors. Thus, inhibiting microglial activation may represent an attractive approach for preventing neuroinflammatory disorders. The objective of this study was to investigate the effect of narciclasine (NA) on lipopolysaccharide (LPS)-induced neuroinflammation by evaluating related markers and neurotoxic factors.

METHODS

BV-2 cells were pre-incubated with NA at 0.1, 0.2, and 0.3 µM for 1h, and then co-treated with LPS for 12 h. Cellular medium and lysates were measured using a nitric oxide assay, enzyme-link immunosorbent assay (ELISA), western blotting, kinase activity assay, luciferase assay, and immunofluorescence assay. C57BL/6N mice were orally administered NA and intraperitoneally injected with LPS, and the cerebral cortex was examined using western blotting and immunofluorescence assays.

RESULTS

NA showed novel pharmacological activity, inhibiting pro-inflammatory factors, including TNF-α, IL-6, IL-18, NO, and PGE₂, but increasing the anti-inflammatory cytokines IL-10 and TGF-β1 in LPS-induced microglial cells. Moreover, NA also attenuated the LPS-induced mRNA and proteins of iNOS and COX-2. The mechanistic study indicated that NA attenuates the secretion of pro-inflammatory factor by down-regulating the Akt/IKK/NF-κB and JNK signaling pathways, and directly inhibits the catalytic activity of IKKα/β. Furthermore, we found that NA also reduced the expression of the microglial markers Iba-1, COX-2, and TNF-α in the mouse brain.

CONCLUSION

NA inhibits the over-expression of pro-inflammatory factors but it promotes anti-inflammatory cytokines by down-regulating the Akt/IKK/NF-κB and JNK signaling pathways in experimental models. Thus, NA may be a potential candidate for relieving neuroinflammation.

Marine Natural Products: Promising Candidates in the Modulation of Gut-Brain Axis towards Neuroprotection

In recent decades, several neuroprotective agents have been provided in combating neuronal dysfunctions; however, no effective treatment has been found towards the complete eradication of neurodegenerative diseases. From the pathophysiological point of view, growing studies are indicating a bidirectional relationship between gut and brain termed gut-brain axis in the context of health/disease. Revealing the gut-brain axis has survived new hopes in the prevention, management, and treatment of neurodegenerative diseases. Accordingly, introducing novel alternative therapies in regulating the gut-brain axis seems to be an emerging concept to pave the road in fighting neurodegenerative diseases. Growing studies have developed marine-derived natural products as hopeful candidates in a simultaneous targeting of gut-brain dysregulated mediators towards neuroprotection. Of marine natural products, carotenoids (e.g., fucoxanthin, and astaxanthin), phytosterols (e.g., fucosterol), polysaccharides (e.g., fucoidan, chitosan, alginate, and laminarin), macrolactins (e.g., macrolactin A), diterpenes (e.g., lobocrasol, excavatolide B, and crassumol E) and sesquiterpenes (e.g., zonarol) have shown to be promising candidates in modulating gut-brain axis. The aforementioned marine natural products are potential regulators of inflammatory, apoptotic, and oxidative stress mediators towards a bidirectional regulation of the gut-brain axis. The present study aims at describing the gut-brain axis, the importance of gut microbiota in neurological diseases, as well as the modulatory role of marine natural products towards neuroprotection.

Fucoxanthin inhibits lipopolysaccharide-induced inflammation and oxidative stress by activating nuclear factor E2-related factor 2 via the phosphatidylinositol 3-kinase/AKT pathway in macrophages

PURPOSE

Anti-inflammatory and antioxidant effects of fucoxanthin (FCX), a xanthophyll carotenoid, have been suggested. However, underlying mechanisms are elusive. The objective of this study was to elucidate the mechanisms by which FCX and its metabolites inhibit lipopolysaccharide (LPS)-induced inflammation and oxidative stress in macrophages.

METHODS

The effects of the FCX on mRNA and protein expression of pro-inflammatory cytokines and antioxidant genes, and reactive oxygen species (ROS) accumulation were determined in RAW 264.7 macrophages. A potential role of FCX in the modulation of phosphatidylinositol 3-kinase (PI3K)/AKT/nuclear E2-related factor 2 (NRF2) axis was evaluated.

RESULTS

FCX significantly decreased LPS-induced interleukin (Il)6, Il1b, and tumor necrosis factor α (Tnf) mRNA abundance and TNFα secretion. FCX attenuated LPS or tert-butyl-hydroperoxide-induced ROS accumulation with concomitant increases in the expression of antioxidant enzymes. Also, trolox equivalent antioxidant capacity assay demonstrated that FCX had a potent free radical scavenging property. FCX markedly increased nuclear translocation of NRF2 in LPS-treated macrophages, consequently inducing its target gene expression. Interestingly, the effect of FCX on NRF2 nuclear translocation was noticeably diminished by LY294002, an inhibitor of PI3K, but not by inhibitors of mitogen-activated protein kinases. Phosphorylation of AKT, a downstream element of PI3K, was also markedly increased by FCX. FCX metabolites, such as fucoxanthinol and amarouciaxanthin A, significantly attenuated LPS-induced ROS accumulation and pro-inflammatory cytokine expression.

CONCLUSION

FCX exerts anti-inflammatory and antioxidant effects by the activation of NRF2 in the macrophages activated by LPS, which is mediated, at least in part, through the PI3K/AKT pathway.

Adrenomedullin 2 attenuates LPS-induced inflammation in microglia cells by receptor-mediated cAMP-PKA pathway

Inflammation plays a critical role in the development of neurodegenerative diseases. Adrenomedullin 2 (AM2), a member of the calcitonin gene-related peptide family, has been known to have anti-inflammatory effects. Here, we evaluated the anti-inflammatory effects of AM2 in LPS-activated microglia and BV2 cells. The endogenous mRNA and protein expressions of AM2, calcitonin receptor-like receptor (CLR), receptor activity-modifying proteins (RAMPs) including RAMP1, RAMP2 and RAMP3 and the production of inflammatory mediators including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) were detected by RT-PCR and Western blot. Our results revealed that LPS (1 μg/mL) significantly stimulated CLR, RAMP1, RAMP2 and RAMP3 protein expressions in BV2 microglia cells, but AM2 had a significant decrease. However, the mRNA levels of AM2, CLR, and RAMP1/2/3 were all markedly increased. LPS also induced obvious increases in mRNA and protein levels of the inflammatory mediators (TNF-α, IL-1β, COX2 and iNOS). More importantly, AM2 (10 nM) administration effectively inhibited the mRNA and protein expressions of these mediators induced by LPS and increased the cAMP content in LPS-stimulated BV2 cells. Furthermore, the antagonism with AM2 receptor antagonist IMD17-47, adrenomedullin (AM) receptor antagonist by AM22-52 or the inhibition of protein kinase A (PKA) activation by P1195 effectively prevented the inhibitory role of AM2 in LPS-induced production of the above inflammatory mediators. In conclusion, AM2 inhibits LPS-induced inflammation in BV2 microglia cells that may be mainly through AM receptor-mediated cAMP-PKA pathway. Our results indicate AM2 plays an important protective role in microglia inflammation, suggesting therapeutic potential for AM2 in neuroinflammation diseases caused by activated microglia.

Fucoxanthin from microalgae Phaeodactylum tricornutum inhibits pro-inflammatory cytokines by regulating both NF-κB and NLRP3 inflammasome activation

Pro-inflammatory cytokines such as IL-1β, IL-6, and TNF-α are mediated by the activation of various kinds of signaling pathways in the innate immune system. Particularly, NF-κB and NLRP3 inflammasome signaling are involved in the production and secretion of these cytokines. Each signaling is participated in the two steps necessary for IL-1β, a representative pro-inflammatory cytokine, to be processed into a form secreted by cells. In the priming step stimulated by LPS, pro-IL-1β is synthesized through NF-κB activation. Pro-IL-1β cleavages into mature IL-1β by formed NLRP3 inflammasome in the activation step induced by ATP. The mature form of IL-1β is subsequently secreted out of the cell, causing inflammation. Moreover, IL-6 and TNF-α are known to increase in NLRP3 inflammasome-mediated conditions. Here, we found that fucoxanthin, one of the major components of Phaeodactylum tricornutum, has an inhibitory effect on NF-κB and NLRP3 inflammasome activation induced by the combination of LPS and ATP in bone marrow-derived immune cells as well as astrocytes. Fucoxanthin, which is abundant in the EtOH fraction of Phaeodactylum tricornutum extracts, has shown to have less cell toxicity and found to decrease the production of major pro-inflammatory cytokines such as IL-1β, IL-6, and TNF-α. Fucoxanthin has also shown to suppress the expression of cleaved caspase-1 and the oligomerization of ASC, which are the main components of the NLRP3 inflammasome. Furthermore, phosphorylated IκBα and pro-IL-1β expression decreased in the presence of fucoxanthin, suggesting that fucoxanthin can negatively regulate the priming step of inflammasome signaling. Thus, our results provide reliable evidence that fucoxanthin may serve as a key candidate in the development of potential therapeutic agents for inflammatory diseases as well as neurodegenerative diseases caused by NF-κB and NLRP3 inflammasome activation.

Benefits under the Sea: The Role of Marine Compounds in Neurodegenerative Disorders

Marine habitats offer a rich reservoir of new bioactive compounds with great pharmaceutical potential; the variety of these molecules is unique, and its production is favored by the chemical and physical conditions of the sea. It is known that marine organisms can synthesize bioactive molecules to survive from atypical environmental conditions, such as oxidative stress, photodynamic damage, and extreme temperature. Recent evidence proposed a beneficial role of these compounds for human health. In particular, xanthines, bryostatin, and 11-dehydrosinulariolide displayed encouraging neuroprotective effects in neurodegenerative disorders. This review will focus on the most promising marine drugs' neuroprotective potential for neurodegenerative disorders, such as Parkinson's and Alzheimer's diseases. We will describe these marine compounds' potential as adjuvant therapies for neurodegenerative diseases, based on their antioxidant, anti-inflammatory, and anti-apoptotic properties.