Mixture of Phlorotannin and Fucoidan from Ecklonia cava Prevents the Aβ-Induced Cognitive Decline with Mitochondrial and Cholinergic Activation

Optimization of Nanoencapsulation of Codium tomentosum Extract and Its Potential Application in Yogurt Fortification

Marine macroalgae are excellent sources of bioactive compounds recognized by their pharmaceutical and biomedical potential. A subcritical water extraction (SWE) was applied to the macroalga Codium tomentosum, and the extract was used to prepare phytosomes. A Box-Behnken design was applied to optimize the entrapment efficiency. These phytosomes were further modified with DSPE-PEG (2000)-maleimide and apolipoprotein E and characterized by dynamic light scattering, UV spectrophotometry, octanol/water partition coefficient, differential scanning calorimetry, and Fourier transform infrared spectroscopy. As proof of concept, prototypes of functional food tailored to the elderly were produced. Yogurts were fortified with seaweed extract or phytosomes, and physicochemical properties and proximal composition (pH, acidity, syneresis, moisture, peroxides, proteins, total lipids, sugar content, ash, and mineral composition) were analyzed. The antioxidant and the inhibition capacity of two brain enzymes, cholinesterases (AChE and BuChE), involved in the pathogenesis of Alzheimer's disease, were also evaluated in the final prototypes. Despite their unappealing sensory characteristics, the results are promising for integrating marine extracts with potential neuroprotective effects into functional foods.

Effects of a mitochondrial calcium uniporter and P-selectin inhibitors on neural injury induced by global cerebral ischemia-reperfusion in male rats

Neural injury following ischemia-reperfusion (I/R) is induced by multiple pathophysiological pathways. This study aimed to use mitochondrial calcium channel and p-selectin inhibitors to weaken these pathways. One hundred and two rats were randomly divided into six groups. In the sham group, cerebral I/R induction and drug intervention were not performed. In the I/R group, cerebral I/R induction was induced. In the RR + FCN group, animals received only ruthenium red (RR) and fucoidan (FCN) intraperitoneally without I/R induction. In the I/R + RR group, animals received RR during the cerebral I/R period. In the I/R + FCN group, FCN was administered along with cerebral I/R. In the I/R +(RR + FCN) group, animals exposed to cerebral I/R received a combination of RR and FCN simultaneously. The shuttle box and new object tests were used to assess learning and memory. The superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-1 beta (IL-1β), and tumor necrosis factor-alpha (TNF-α) levels in the hippocampus were measured. Neuronal death in the hippocampal CA1 area was assessed via hematoxylin-eosin staining. FCN and RR significantly decreased the tissue MDA, IL-1β, TNF-α levels while increased the SOD level. These inhibitors significantly reduced learning disorders and cerebral edema following I/R. The rate of neuronal death was significantly lower in each of the receiving RR and FCN groups. This study revealed that the use of FCN and RR significantly attenuated the pathways associated with oxidative stress and inflammation as well as neuronal death following cerebral I/R, thereby reducing learning and memory impairments. The effects of neuroprotection were further determined when two inhibitors were used simultaneously. HIGHLIGHTS: Cerebral ischemia-reperfusion is associated with many neurological, sensory and motor defects. Multiple pathways of neural pathophysiology are activated during cerebral ischemia-reperfusion. The Administration of ruthenium and fucoidan weakens inflammatory pathways, oxidative stress, and learning dysfunctions caused by cerebral ischemia and reperfusion. Stronger Neuroprotective effects were observed during the simultaneous administration of ruthenium and fucoidan.

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.

Exposure to an enriched environment and fucoidan supplementation ameliorate learning and memory function in rats subjected to global cerebral ischemia

An enriched environment (EE) constitutes a proficient strategy that instigates social, cognitive, and motor faculties, fostering healing and heightening learning and memory function after ischemia, while fucoidan derived from brown seaweed encompasses a diverse array of bioactivities and is known to possess neuroprotective properties. This study aims to investigate the effectiveness of combining fucoidan and EE in a rat model of vascular dementia to overcome cognitive challenges. The rats were randomly assigned as Sham, Lesion - 4-vessel occlusion (4VO) i.e., transient global cerebral ischemia (tGCI), 4VO + F50mg/kg, 4VO + EE, and 4VO + F50mg/kg + EE. At the end of the study periods, the rats were exposed to the Novel object task, T-maze, and the Morris water maze. The profile of hippocampal pyramidal neurons and their dendrites was assessed through the CFV, and Golgi cox stained brain sections. Neuroinflammatory markers (IL-1β, IL-6, NF-κB, TNF-α) and synaptogenic markers (BDNF, SYP, PSD-95) were evaluated through western blot analysis. The levels of oxidative stress marker (LPO) and antioxidants (SOD, CAT, GSH, GST, GPX) in the hippocampus were quantified through biochemical assay. The findings revealed that the cognitive deficits were significantly reduced in both the 4VO + F50mg/kg and 4VO + F50mg/kg + EE treatment groups and inflammatory markers were reduced with increased antioxidant levels and synaptogenic markers when compared with the lesion group. However, through this study, the combination therapy involving fucoidan and exposure to an EE was proven effective in preserving neural integrity and restoring cognitive function against the damage caused by oxidative stress and inflammation following tGCI.

Phlorotannin Supplement Improves Scopolamine-Induced Memory Dysfunction by Rescuing Synaptic Damage in Mice

This study investigated the efficacy of a phlorotannin supplement (PS) in ameliorating scopolamine (SCO)-induced memory deficits in mice, focusing on synaptic function and the underlying molecular mechanisms. Male C57BL/6N mice were divided into six groups and treated with vehicle, donepezil (5 mg/kg body weight, (BW)), or PS (100, 250, or 500 mg/kg BW) for 6 weeks. Behavioral tests were conducted, followed by Golgi staining, immunofluorescence, and immunoblotting to assess synaptic protein expression and signaling pathways. Behavioral tests showed that PS administration significantly improved SCO-induced memory impairment and restored synaptic protein expression (synaptophysin, synapsin1, and postsynaptic density protein 95) in the hippocampus. Additionally, PS enhanced brain-derived neurotrophic factor (BDNF) signaling and activated the extracellular signal-regulated kinase/CAMP response element binding protein (ERK-CREB) pathway, essential for synaptic plasticity. Our findings demonstrate that PS mitigates SCO-induced memory dysfunction by protecting synaptic integrity and activating the BDNF-ERK-CREB signaling pathway, indicating the potential of PS as a natural intervention for treating memory deficits.

Therapeutic potential of fucoidan in central nervous system disorders: A systematic review

Central nervous system (CNS) disorders have a complicated pathogenesis, and to date, no single mechanism can fully explain them. Most drugs used for CNS disorders primarily aim to manage symptoms and delay disease progression, and none have demonstrated any pathological reversal. Fucoidan is a safe, sulfated polysaccharide from seaweed that exhibits multiple pharmacological effects, and it is anticipated to be a novel treatment for CNS disorders. To assess the possible clinical uses of fucoidan, this review aims to provide an overview of its neuroprotective mechanism in both in vivo and in vitro CNS disease models, as well as its pharmacokinetics and safety. We included 39 articles on the pharmacology of fucoidan in CNS disorders. In vitro and in vivo experiments demonstrate that fucoidan has important roles in regulating lipid metabolism, enhancing the cholinergic system, maintaining the functional integrity of the blood-brain barrier and mitochondria, inhibiting inflammation, and attenuating oxidative stress and apoptosis, highlighting its potential for CNS disease treatment. Fucoidan has a protective effect against CNS disorders. With ongoing research on fucoidan, it is expected that a natural, highly effective, less toxic, and highly potent fucoidan-based drug or nutritional supplement targeting CNS diseases will be developed.

Ecklonia cava Ameliorates Cognitive Impairment on Amyloid β-Induced Neurotoxicity by Modulating Oxidative Stress and Synaptic Function in Institute of Cancer Research (ICR) Mice

This study investigated the neuroprotective effect of 70% ethanol extract of Ecklonia cava (EE) in amyloid beta (Aβ)-induced cognitive deficit mice. As a result of analyzing the bioactive compounds in EE, nine compounds were identified using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). In particular, the diekcol content was quantified by high-performance liquid chromatography with diode-array detection (DAD-HPLC). Biochemical analysis was performed on brain tissue to determine the mechanism of the cognitive function improvement effect of EE. The result showed that EE ameliorated learning and memory decline in behavioral tests on Aβ-induced mice. EE also attenuated oxidative stress by regulating malondialdehyde (MDA) content, reduced glutathione (GSH), and superoxide dismutase (SOD) levels. Similarly, EE also improved mitochondrial dysfunction as mitochondrial membrane potential, ATP production, and reactive oxygen species (ROS) levels. In addition, EE enhanced synapse function by modulating acetylcholine-related enzymes and synaptic structural proteins in the whole brain, hippocampus, and cerebral cortex tissues. Also, EE regulated Aβ-induced apoptosis and inflammation through the c-Jun N-terminal kinase (JNK) and nuclear factor-kappa B (NF-κB) signaling pathways. Furthermore, EE protected neurotoxicity by increasing brain-derived neurotrophic factor (BDNF) production. These results suggest that EE may be used as a dietary supplement for the prevention and treatment of Alzheimer's disease (AD).

Multiple roles of fucoxanthin and astaxanthin against Alzheimer's disease: Their pharmacological potential and therapeutic insights

Alzheimer's disease (AD) is the most devastating neurodegenerative disorder affecting the elderly. The exact pathology of AD is not yet fully understood and several hallmarks such as the deposition of amyloid-β, tau hyperphosphorylation, and neuroinflammation, as well as mitochondrial, metal ions, autophagy, and cholinergic dysfunctions are known as pathologic features of AD. Since no definitive treatment has been proposed to target AD to date, many natural products have shown promising preventive potentials and contributed to slowing down the disease progression. Algae is a promising source of novel bioactive substances known to prevent neurodegenerative disorders including AD. In this context, fucoxanthin and astaxanthin, natural carotenoids abundant in algae, has shown to possess neuroprotective properties through antioxidant, and anti-inflammatory characteristics in modulating the symptoms of AD. Fucoxanthin and astaxanthin exhibit anti-AD activities by inhibition of AChE, BuChE, BACE-1, and MAO, suppression of Aβ accumulation. Also, fucoxanthin and astaxanthin inhibit apoptosis induced by Aβ_1-42 and H₂O₂-induced cytotoxicity, and modulate the antioxidant enzymes (SOD and CAT), through inhibition of the ERK pathway. Moreover, cellular and animal studies on the beneficial effects of fucoxanthin and astaxanthin against AD were also reviewed. The potential role of fucoxanthin and astaxanthin exhibits great efficacy for the management of AD by acting on multiple targets.

Advances in Anti-Diabetic Cognitive Dysfunction Effect of Erigeron Breviscapus (Vaniot) Hand-Mazz

Diabetic cognitive dysfunction (DCD) is the decline in memory, learning, and executive function caused by diabetes. Although its pathogenesis is unclear, molecular biologists have proposed various hypotheses, including insulin resistance, amyloid β hypothesis, tau protein hyperphosphorylation hypothesis, oxidative stress and neuroinflammation. DCD patients have no particular treatment options and current pharmacological regimens are suboptimal. In recent years, Chinese medicine research has shown that herbs with multi-component, multi-pathway and multi-target synergistic activities can prevent and treat DCD. Yunnan is home to the medicinal herb Erigeron breviscapus (Vant.) Hand-Mazz. (EBHM). Studies have shown that EBHM and its active components have a wide range of pharmacological effects and applications in cognitive disorders. EBHM's anti-DCD properties have been seldom reviewed. Through a literature study, we were able to evaluate the likely pathophysiology of DCD, prescribe anti-DCD medication and better grasp EBHM's therapeutic potential. EBHM's pharmacological mechanism and active components for DCD treatment were also summarized.

Recent advances in biological properties of brown algae-derived compounds for nutraceutical applications

The increasing demand for nutraceuticals in the circular economy era has driven the research toward studying bioactive compounds from renewable underexploited resources. In this regard, the exploration of brown algae has shown significant growth and maintains a great promise for the future. One possible explanation could be that brown algae are rich sources of nutritional compounds (polyunsaturated fatty acids, fiber, proteins, minerals, and vitamins) and unique metabolic compounds (phlorotannins, fucoxanthin, fucoidan) with promising biological activities that make them good candidates for nutraceutical applications with increased value-added. In this review, a deep description of bioactive compounds from brown algae is presented. In addition, recent advances in biological activities ascribed to these compounds through in vitro and in vivo assays are pointed out. Delivery strategies to overcome some drawbacks related to the direct application of algae-derived compounds (low solubility, thermal instability, bioavailability, unpleasant organoleptic properties) are also reviewed. Finally, current commercial and legal statuses of ingredients from brown algae are presented, considering future therapeutical and market perspectives as nutraceuticals.

Molecular Targets of Brown Algae Phlorotannins for the Therapy of Inflammatory Processes of Various Origins

Inflammatory reactions are part of a complex biological response that plays a vital role in the appearance of various stimuli resulting from tissue and cell damage, the invasion of pathogenic bacteria, and the formation of the subsequent adaptive immune response. The production of many triggers and mediators of inflammation, which are inducers of pro-inflammatory factors, is controlled by numerous differentiation programs, through which inflammation is resolved and tissue homeostasis is restored. However, prolonged inflammatory responses or dysregulation of pro-inflammatory mechanisms can lead to chronic inflammation. Modern advances in biotechnology have made it possible to characterize the anti-inflammatory activity of phlorotannins, polyphenolic compounds from brown seaweed, and the mechanisms by which they modulate the inflammatory response. The purpose of this review is to analyze and summarize the results of numerous experimental in vitro and in vivo studies, illustrating the regulatory mechanisms of these compounds, which have a wide range of biological effects on the body. The results of these studies and the need for further research are discussed.

Transcranial photobiomodulation therapy ameliorates perioperative neurocognitive disorder through modulation of mitochondrial function in aged mice

Perioperative neurocognitive disorder (PND) is a serious nervous system complication characterized by progressive cognitive impairment, especially in geriatric population. However, the neuropathogenesis of PND is complex, and there are no approved disease-modifying therapeutic options. Mitochondrial dysfunction has been demonstrated to contribute to the occurrence and development of PND. Transcranial near-infrared (tNIR) light treatment helps to improve mitochondrial dysfunction and enhance cognition, but its effect on PND remains unclear. Here, we evaluated the effect of tNIR light treatment on PND caused by anesthesia and surgery in aged mice. We built the PND models with 18-month C57BL/6 male mice by exploratory laparotomy under isoflurane inhalation anesthesia, and treated by tNIR light with wavelength 810 nm for 2 weeks. The short-term and long-term changes in cognitive function were analyzed by behavioral tests. We further explored the effects of tNIR light on mitochondria, synapses, neurons, and signaling pathways through different experimental methods. The results demonstrated that the cognitive impairment and mitochondrial dysfunction in PND mice were ameliorated after tNIR light treatment. Further experiments demonstrated that photobiomodulation therapy (PBMT) increased synapse-related protein expression, neuronal survival, and protected synapse from depletion. Moreover, downregulated sirtuin 1 (SIRT1) and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) were increased after tNIR light treatment. Our results suggested that tNIR light was an effective treatment of PND through PBMT effect, accompanied by synaptic and neuronal improvement. The improvement of mitochondrial dysfunction mediated by SIRT1/PGC-1α signaling pathway might participate in this process. Those findings might provide a novel and noninvasive therapeutic target for PND.