Fucoidan⁻Fucoxanthin Ameliorated Cardiac Function via IRS1/GRB2/ SOS1, GSK3β/CREB Pathways and Metabolic Pathways in Senescent Mice

Management of ROS and Regulatory Cell Death in Myocardial Ischemia-Reperfusion Injury

Myocardial ischemia-reperfusion injury (MIRI) is fatal to patients, leading to cardiomyocyte death and myocardial remodeling. Reactive oxygen species (ROS) and oxidative stress play important roles in MIRI. There is a complex crosstalk between ROS and regulatory cell deaths (RCD) in cardiomyocytes, such as apoptosis, pyroptosis, autophagy, and ferroptosis. ROS is a double-edged sword. A reasonable level of ROS maintains the normal physiological activity of myocardial cells. However, during myocardial ischemia-reperfusion, excessive ROS generation accelerates myocardial damage through a variety of biological pathways. ROS regulates cardiomyocyte RCD through various molecular mechanisms. Targeting the removal of excess ROS has been considered an effective way to reverse myocardial damage. Many studies have applied antioxidant drugs or new advanced materials to reduce ROS levels to alleviate MIRI. Although the road from laboratory to clinic has been difficult, many scholars still persevere. This article reviews the molecular mechanisms of ROS inhibition to regulate cardiomyocyte RCD, with a view to providing new insights into prevention and treatment strategies for MIRI.

The Ocean's Pharmacy: Health Discoveries in Marine Algae

Non-communicable diseases (NCDs) represent a global health challenge, constituting a major cause of mortality and disease burden in the 21st century. Addressing the prevention and management of NCDs is crucial for improving global public health, emphasizing the need for comprehensive strategies, early interventions, and innovative therapeutic approaches to mitigate their far-reaching consequences. Marine organisms, mainly algae, produce diverse marine natural products with significant therapeutic potential. Harnessing the largely untapped potential of algae could revolutionize drug development and contribute to combating NCDs, marking a crucial step toward natural and targeted therapeutic approaches. This review examines bioactive extracts, compounds, and commercial products derived from macro- and microalgae, exploring their protective properties against oxidative stress, inflammation, cardiovascular, gastrointestinal, metabolic diseases, and cancer across in vitro, cell-based, in vivo, and clinical studies. Most research focuses on macroalgae, demonstrating antioxidant, anti-inflammatory, cardioprotective, gut health modulation, metabolic health promotion, and anti-cancer effects. Microalgae products also exhibit anti-inflammatory, cardioprotective, and anti-cancer properties. Although studies mainly investigated extracts and fractions, isolated compounds from algae have also been explored. Notably, polysaccharides, phlorotannins, carotenoids, and terpenes emerge as prominent compounds, collectively representing 42.4% of the investigated compounds.

Mechanistic Implications of GSK and CREB Crosstalk in Ischemia Injury

Ischemia-reperfusion (IR) injury is a damage to an organ when the blood supply is less than the demand required for normal functioning, leading to exacerbation of cellular dysfunction and death. IR injury occurs in different organs like the kidney, liver, heart, brain, etc., and may not only involve the ischemic organ but also cause systemic damage to distant organs. Oxygen-glucose deprivation in cells causes oxidative stress, calcium overloading, inflammation, and apoptosis. CREB is an essential integrator of the body's various physiological systems, and it is widely accepted that dysfunction of CREB signaling is involved in many diseases, including ischemia-reperfusion injury. The activation of CREB can provide life to a cell and increase the cell's survival after ischemia. Hence, GSK/CREB signaling pathway can provide significant protection to cells of different organs after ischemia and emerges as a futuristic strategy for managing ischemia-reperfusion injury. Different signaling pathways such as MAPK/ERK, TLR4/MyD88, RISK, Nrf2, and NF-κB, get altered during IR injury by the modulation of GSK-3 and CREB (cyclic AMP response element (CRE)-binding protein). GSK-3 (protein kinase B) and CREB are the downstream targets for fulfilling the roles of various signaling pathways. Calcium overloading during ischemia increases the expression of calcium-calmodulin-dependent protein kinase (CaMK), which subsequently activates CREB-mediated transcription, thus promoting the survival of cells. Furthermore, this review highlights the crosstalk between GSK-3 and CREB, promoting survival and rendering the cells resistant to subsequent severe ischemia.

Fucoxanthin alleviated myocardial ischemia and reperfusion injury through inhibition of ferroptosis via the NRF2 signaling pathway

Background: Myocardial ischemia and reperfusion injury (MIRI) is a severe complication of revascularization therapy in patients with myocardial infarction. Therefore, there is an urgent requirement to find more therapeutic solutions for MIRI. Recently, ferroptosis, which is characterized by lipid peroxidation, was considered a critical contributor to MIRI. Fucoxanthin (FX), a natural antioxidant carotenoid, which is abundant in brown seaweed, exerts protective effects under various pathological conditions. However, whether FX alleviates MIRI is unclear. This study aims to clarify the effects of FX on MIRI. Methods: Mice with left anterior descending artery ligation and reperfusion were used as in vivo models. Neonatal rat cardiomyocytes (NRCs) induced with hypoxia and reperfusion were used as in vitro models. TTC-Evans blue staining was performed to validate the infarction size. Transmission electron microscopy was employed to detect mitochondrial injury in cardiomyocytes. In addition, 4 weeks after MIRI, echocardiography was performed to measure cardiac function; fluorescent probes and western blots were used to detect ferroptosis. Results: TTC-Evans blue staining showed that FX reduced the infarction size induced by MIRI. Transmission electron microscopy showed that FX ameliorated the MIRI-induced myofibril loss and mitochondrion shrinkage. Furthermore, FX improved LVEF and LVFS and inhibited myocardial hypertrophy and fibrosis after 4 weeks in mice with MIRI. In the in vitro study, calcein AM/PI staining and TUNEL staining showed that FX reduced cell death caused by hypoxia and reperfusion treatment. DCFH-DA and MitoSOX probes indicated that FX inhibited cellular and mitochondrial reactive oxygen species (ROS). Moreover, C11-BODIPY 581/591 staining, ferro-orange staining, MDA assay, Fe2+ assay, 4-hydroxynonenal enzyme-linked immunosorbent assay, and western blot were performed and the results revealed that FX ameliorated ferroptosis in vitro and in vivo, as indicated by inhibiting lipid ROS and Fe2+ release, as well as by modulating ferroptosis hallmark FTH, TFRC, and GPX4 expression. Additionally, the protective effects of FX were eliminated by the NRF2 inhibitor brusatol, as observed from western blotting, C11-BODIPY 581/591 staining, and calcein AM/PI staining, indicating that FX exerted cardio-protective effects on MIRI through the NRF2 pathway. Conclusion: Our study showed that FX alleviated MIRI through the inhibition of ferroptosis via the NRF2 signaling pathway.

Fucoidan from Sargassum wightii reduces oxidative stress through upregulating Nrf2/HO-1 signaling pathway in alloxan-induced diabetic cardiomyopathy rats

BACKGROUND

Diabetic cardiomyopathy (DCM) is a form of cardiac dysfunction caused by diabetes, increasing heart failure and death. Studies shown that hyperglycemia-induced oxidative stress significantly affects heart structure and functional changes during diabetic cardiomyopathy. Fucoidans are sulfated polysaccharide derived from naturally available seaweeds and reported for various biological functions such as antioxidant, anti-diabetic, and anti-inflammatory. However, the therapeutic potential of Indian seaweeds against DCM remains largely unexplored. Therefore, the current study aimed to work on the cardioprotective effect of extracted fucoidan from Sargassum wightii (SwF) in alloxan-induced DCM.

METHODS AND RESULTS

Diabetes (DM) was induced with alloxan monohydrate (150 mg/kg-1) dissolved in Nacl (0.9%) overnight-fasted rats. Group III, IV rats were DM induced, followed by treated with SwF (150 mg/kg-1) and (300 mg/kg-1). Group V and VI were non-diabetic rats and received SwF (150 mg/kg-1) and (300 mg/kg-1). SwF reduced classical progressive DM complications such as hyperglycemia, polydipsia, polyphagia, and polyurea in alloxan-induced diabetic rats. Biochemical analysis showed that SwF decreased blood glucose, cardiac markers enzymes, and lipid peroxidation levels compared to diabetic rats. SwF administration significantly increased Nrf2, HO-1, SOD, Catalase, and NQO1 gene expression. In addition, SwF-treated rats showed reduced heart tissue damage with increased Nrf2 and HO-1 protein expression.

CONCLUSION

The current research concludes that targeting oxidative stress with SwF provided an effective role in the prevention of DCM. Thus, fucoidan could be used to develop functional food ingredients for DCM.

Plant-Derived Biomaterials and Their Potential in Cardiac Tissue Repair

Cardiovascular disease remains the leading cause of mortality worldwide. The inability of cardiac tissue to regenerate after an infarction results in scar tissue formation, leading to cardiac dysfunction. Therefore, cardiac repair has always been a popular research topic. Recent advances in tissue engineering and regenerative medicine offer promising solutions combining stem cells and biomaterials to construct tissue substitutes that could have functions similar to healthy cardiac tissue. Among these biomaterials, plant-derived biomaterials show great promise in supporting cell growth due to their inherent biocompatibility, biodegradability, and mechanical stability. More importantly, plant-derived materials have reduced immunogenic properties compared to popular animal-derived materials (e.g., collagen and gelatin). In addition, they also offer improved wettability compared to synthetic materials. To date, limited literature is available to systemically summarize the progression of plant-derived biomaterials in cardiac tissue repair. Herein, this paper highlights the most common plant-derived biomaterials from both land and marine plants. The beneficial properties of these materials for tissue repair are further discussed. More importantly, the applications of plant-derived biomaterials in cardiac tissue engineering, including tissue-engineered scaffolds, bioink in 3D biofabrication, delivery vehicles, and bioactive molecules, are also summarized using the latest preclinical and clinical examples.

Fucoidan mitigates gastric ulcer injury through managing inflammation, oxidative stress, and NLRP3-mediated pyroptosis

This study aimed to elucidate the gastro-protective effect of fucoidan against ethanol-induced gastric ulcer mediated via NLRP3-induced pyroptosis as an underlying mechanism, not yet assessed in prior research. Forty-eight male Albino mice were divided into six groups: Group I (normal control), group II (Ulcer/ethanol control), group III (Omeprazole + ethanol), group IV (fucoidan 25 mg + ethanol), group V (fucoidan 50 mg + ethanol) and group VI (fucoidan only). Fucoidan was administered orally for seven consecutive days followed by ulcer induction by a single oral dose of ethanol. Using colorimetric analysis, ELISA, qRT-PCR, histological assessment, and immunohistochemical studies, the results revealed that ethanol-induced ulcer exhibited an ulcer score of 42.5 ± 5.1 and a significant increase (p < 0.05) in malondialdehyde (MDA), nuclear factor kappa B (NF-κB), and interleukin 6 (IL-6) with a significant decrease in the gastro-protective mediators, prostaglandin E2 (PGE2), superoxide dismutase (SOD) and glutathione (GSH), accompanied with an increase in NLRP3, interleukin 1β (IL-1β), interleukin 18 (IL-18), caspase 1, caspase 11, gasdermin D, and toll-like receptor 4 (TLR4), compared with the normal control. Pre-treatment with fucoidan showed a comparable result with omeprazole. Additionally, pre-treatments elevated the levels of the gastro-protective mediators and lessened oxidative stress, relative to the positive control findings. Conclusively, fucoidan has a promising gastro-protective role by inhibiting inflammation and pyroptosis.

Autologous Extracellular Vesicles Attenuate Cardiac Injury in Experimental Atherosclerotic Renovascular Disease More Effectively Than Their Parent Mesenchymal Stem/Stromal Cells

Atherosclerotic renovascular disease (RVD) leads to hypertension, chronic kidney disease (CKD), and heart disease. Intrarenal delivery of mesenchymal stem cells (MSCs) and MSC-derived extracellular vesicles (EVs) attenuate renal injury and suppress release of inflammatory cytokines in porcine RVD. We hypothesized that this strategy would also be useful for cardioprotection. Pigs with renovascular hypertension and metabolic syndrome were studied 4 weeks after treatment with a single intrarenal infusion of autologous MSCs, EVs, or vehicle. Cardiac structure and function were assessed in vivo, and myocardial remodeling and expression of the pro-fibrotic factor growth factor receptor-bound protein-2 (Grb2) were measured ex-vivo. Inflammatory cytokine levels were measured in the systemic circulation and myocardial tissue. Blood pressure was elevated in all RVD groups, but serum creatinine increased in RVD and decreased in both RVD + MSCs and RVD + EVs. RVD-induced diastolic dysfunction (lower E/A ratio) was normalized in both MSCs- and EVs- treated pigs. Intrarenal delivery of MSCs and EVs also attenuated RVD-induced myocardial fibrosis, collagen deposition, and Grb2 expression, yet EVs restored capillary density and inflammation more effectively than MSCs. These observations suggest that autologous EVs attenuate cardiac injury in experimental RVD more effectively than their parent MSCs.

Sulfated fuco-manno-glucuronogalactan alleviates pancreatic beta cell senescence via PI3K/AKT/FoxO1 pathway

Appearance of senescent beta cells in the pancreas leads to the onset of type 2 diabetes (T2D). The structural analysis of a sulfated fuco-manno-glucuronogalactan (SFGG) indicated SFGG had the backbones of interspersing 1, 3-linked β-D-GlcpA residues, 1, 4-linked α-D-Galp residues, and alternating 1, 2-linked α-D-Manp residues and 1, 4-linked β-D-GlcpA residues, sulfated at C6 of Man residues, C2/C3/C4 of Fuc residues and C3/C6 of Gal residues, and branched at C3 of Man residues. SFGG effectively alleviated senescence-related phenotypes in vitro and in vivo, including cell cycle, senescence-associated β-galactosidase, DNA damage and senescence-associated secretory phenotype (SASP) -associated cytokines and hall markers of senescence. SFGG also alleviated beta cell dysfunction in insulin synthesis and glucose-stimulated insulin secretion. Mechanistically, SFGG attenuated senescence and improved beta cell function via PI3K/AKT/FoxO1 signaling pathway. Therefore, SFGG could be used for beta cell senescence treatment and alleviation of the progression of T2D.

Fucoidan Protects against Doxorubicin-Induced Cardiotoxicity by Reducing Oxidative Stress and Preventing Mitochondrial Function Injury

Doxorubicin (DOXO) is a potent chemotherapeutic drug widely used to treat various cancers. However, its clinical application is limited due to serious adverse effects on dose-dependent cardiotoxicity. Although the underlying mechanism has not been fully clarified, DOXO-induced cardiotoxicity has been mainly attributed to the accumulation of reactive oxygen species (ROS) in cardiomyocytes. Fucoidan, as a kind of sulphated polysaccharide existing in numerous brown seaweed, has potent anti-oxidant, immune-regulatory, anti-tumor, anti-coagulate and anti-viral activities. Here, we explore the potential protective role and mechanism of fucoidan in DOXO-induced cardiotoxicity in mice. Our results show that oral fucoidan supplement exerts potent protective effects against DOXO-induced cardiotoxicity by reducing oxidative stress and preventing mitochondrial function injury. The improved effect of fucoidan on DOXO-induced cardiotoxicity was evaluated by echocardiography, cardiac myocytes size and cardiac fibrosis analysis, and the expression of genes related to cardiac dysfunction and remodeling. Fucoidan reduced the ROS content and the MDA levels but enhanced the activity of antioxidant enzymes GSH-PX and SOD in the mouse serum in a DOXO-induced cardiotoxicity model. In addition, fucoidan also increased the ATP production capacity and restored the levels of a mitochondrial respiratory chain complex in heart tissue. Collectively, this study highlights fucoidan as a potential polysaccharide for protecting against DOXO-induced cardiovascular diseases.

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.

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.

The interactive effects of exercise training and functional feeds on the cardiovascular performance of rainbow trout (Oncorhynchus mykiss) at high temperatures

The cardiovascular performance of salmonids in aquaculture can be impaired by acute climate warming, posing risks for fish survival. Exercise training and functional feeds have been shown to be cardioprotective in mammals but their action on the fish heart and its upper thermal performance has not been studied. To investigate this, rainbow trout were trained at a moderate water velocity of 1 body length per second (bl s⁻¹) for 6 h per day, either alone or in combination with one of two functional feed-supplements, allicin and fucoidan. After 6 weeks of exercise training and feeding, maximum heart rate and the temperature coefficient of heart rate were significantly higher in the trained fish as compared to untrained ones. There was a slight increase in hematocrit in trained control fish reared on a normal diet (TC group) compared to untrained fish fed with the same diet (CC). This implies that exercise training enhanced oxygen delivery to trout tissues via an increase of cardiac blood flow in warm water. However, cardiac thermal tolerance was not affected by exercise training or feeding, except from the temperature of peak heart rate which was higher in the trained group fed with fucoidan supplement (TF) as compared to the untrained group fed with same diet (CF). Allicin supplement caused a significant reduction in the maximum heart rate and the temperature coefficient of heart rate, especially in trained fish, while fucoidan supplement did not cause any effect on heart rate. No differences were observed in growth performance among groups. However, fish fed with fucoidan-supplemented diet had a slight reduction in feed conversion efficiency. We suggest further investigations to understand the antagonistic effect of allicin supplemental feeding and exercise training on cardiovascular performance. More studies are also required to investigate if other exercise training intensities could increase cardiac thermal tolerance.

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Exercise training at 1 bl s⁻¹ increased the hematocrit values of rainbow trout.

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Exercise training at 1 bl s⁻¹ increased the maximum heart rate and temperature coefficient of rainbow trout.

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Exercise training at 1bl s⁻¹ did not enhance the cardiac thermal tolerance of rainbow trout.

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Functional feeds, allicin and fucoidan, did not improve the cardiovascular system of rainbow trout at high temperatures.

The Critical Studies of Fucoxanthin Research Trends from 1928 to June 2021: A Bibliometric Review

Fucoxanthin is a major carotenoid in brown macroalgae and diatoms that possesses a broad spectrum of health benefits. This review evaluated the research trends of the fucoxanthin field from 1928 to June 2021 using the bibliometric method. The present findings unraveled that the fucoxanthin field has grown quickly in recent years with a total of 2080 publications. Japan was the most active country in producing fucoxanthin publications. Three Japan institutes were listed in the top ten productive institutions, with Hokkaido University being the most prominent institutional contributor in publishing fucoxanthin articles. The most relevant subject area on fucoxanthin was the agricultural and biological sciences category, while most fucoxanthin articles were published in Marine Drugs. A total of four research concepts emerged based on the bibliometric keywords analysis: “bioactivities”, “photosynthesis”, “optimization of process’’, and “environment”. The “bioactivities” of fucoxanthin was identified as the priority in future research. The current analysis highlighted the importance of collaboration and suggested that global collaboration could be the key to valorizing and efficiently boosting the consumer acceptability of fucoxanthin. The present bibliometric analysis offers valuable insights into the research trends of fucoxanthin to construct a better future development of this treasurable carotenoid.

Fucoidan as an Autophagy Regulator: Mechanisms and Therapeutic Potentials for Cancer and Other Diseases

Fucoidan, a natural polysaccharide with a variety of classical bioactivities mainly sourced from brown algae, has been extensively studied owing to its favorable pharmacological effects, including anti-inflammatory, anti-tumor, anticoagulant and liver protection. Recently it has been found to play a regulatory role in the processes of autophagy. Autophagy is an important cellular process that effectively protects cells and organisms from stimulating factors such as nutrient deficiency, low cellular ATP levels, metabolic stress, growth factor deprivation and hypoxic conditions. In recent years, many studies have shown that fucoidan can treat human diseases by regulating autophagy process though cell signaling pathways. In this review, we summarize the latest progress in the discovery of natural autophagy regulator of fucoidan for the therapeutic application in cardiac diseases, cancers and liver diseases, aiming to provide the new pharmacological application that fucoidan may treat human diseases by regulating autophagy. Furthermore, we look forward to seeing more diseases that would be treated by autophagy modulator of fucoidan and the discovery of more elaborate autophagy regulation mechanism.

Protective effect of valsartan against doxorubicin-induced cardiotoxicity: Histopathology and metabolomics in vivo study

Doxorubicin (DOX) treatment has been associated with cardiotoxicity. Therefore, it is crucial to search for a therapeutic that can effectively mitigate DOX-induced cardiotoxicity. This study was conducted to investigate the protective effects of valsartan (VAL) against DOX-induced cardiotoxicity. Sprague-Dawley rats were divided into four treatment groups: Group I: Control, Group II: VAL (30 mg/kg, ip), Group III: DOX (15 mg/kg, ip), and Group IV: VAL + DOX (30 + 15 mg/kg, ip). All groups were treated every other day for 14 days. Blood was isolated for biochemical and metabolomics studies, and sections of the heart were also analyzed for histopathological and immunohistochemical alterations to detect changes in P53, BAX, BCL-2, and P62 expression. The combination of VAL + DOX resulted in a marked decrease in cardiac biomarker enzymes (aminotransferase and creatine phosphokinase) compared to DOX monotherapy. In addition, the histopathological examination of the VAL + DOX combination revealed a low percentage of fibrosis and inflammation. Immunohistochemical expression of p53 and BAX was significantly reduced, whereas BCL-2 expression was significantly increased in the VAL + DOX treatment group compared to DOX monotherapy. Also, the combination of VAL + DOX reverses the negative effect of DOX on nuclear p62 expression. Analysis of serum metabolites showed that DOX monotherapy reduced the number of several amino acids, whereas the combination of VAL + DOX restored these metabolic pathways. This study revealed the potential cardioprotective effect of VAL, which may provide novel and promising approaches for managing cardiotoxicity induced by DOX.

Grb2 Induces Cardiorenal Syndrome Type 3: Roles of IL-6, Cardiomyocyte Bioenergetics, and Akt/mTOR Pathway

Cardiorenal syndrome type 3 (CRS-3) is damage to the heart following acute kidney injury (AKI). Although many experiments have found that inflammation, oxidative stress, and cardiomyocyte death are involved in cardiomyocyte pathophysiological alterations during CRS-3, they lack a non-bias analysis to figure out the primary mediator of cardiac dysfunction. Herein proteomic analysis was operated in CRS-3 and growth factor receptor-bound protein 2 (Grb2) was identified as a regulator involving AKI-related myocardial damage. Increased Grb2 was associated with cardiac diastolic dysfunction and mitochondrial bioenergetics impairment; these pathological changes could be reversed through the administration of a Grb2-specific inhibitor during AKI. Molecular investigation illustrated that augmented Grb2 promoted cardiomyocyte mitochondrial metabolism disorder through inhibiting the Akt/mTOR signaling pathway. Besides that, Mouse Inflammation Array Q1 further identified IL-6 as the upstream stimulator of Grb2 upregulation after AKI. Exogenous administration of IL-6 induced cardiomyocyte damage and mitochondrial bioenergetics impairment, whereas these effects were nullified in cardiomyocytes pretreated with Grb2 inhibitor. Our results altogether identify CRS-3 to be caused by the upregulations of IL-6/Grb2 which contribute to cardiac dysfunction through inhibiting the Akt/mTOR signaling pathway and inducing cardiomyocyte mitochondrial bioenergetics impairment. This finding provides a potential target for the clinical treatment of patients with CRS-3.

Combined protective effects of oligo-fucoidan, fucoxanthin, and L-carnitine on the kidneys of chronic kidney disease mice

Chronic kidney disease (CKD) is a common global progressive disease, but there are no ideal drugs for the treatment. Fucoidan and fucoxanthin, and L-carnitine are one of the very few natural products that have a therapeutic effect on CKD in animal experiments. However, the combined effects of these compounds on CKD are unknown. We established a mouse CKD model by right nephrectomy with transient ischemic injury to the left kidney. Oligo-fucoidan and fucoidan were extracted from Laminaria japonica. We fed CKD mice with the two compounds and L-carnitine to evaluate the combined effects on CKD. Oligo-fucoidan and fucoidan inhibited renal fibrosis and reduced serum creatine in CKD mice to a greater extent than any single compound. L-carnitine had no measurable effect on renal fibrosis but promoted the protective effect of the mixture of oligo-fucoidan and fucoidan on renal function in CKD mice. In the two-month safety test, the combined mixture further improved renal function and did not elevate serum aspartate aminotransferase and alanine aminotransferase levels in CKD mice. Furthermore, the weights of CKD mice treated with the combination increased to the normal level. We also found that all oligo-fucoidan, fucoxanthin, and L-carnitine inhibit H2O2-induced apoptosis and activated Akt in rat renal tubular cells. Our results confirm that oligo-fucoidan, fucoxanthin, and L-carnitine have a combined protective effect on the kidneys. The combined mixture may be beneficial for CKD patients.

Aging and Senescence of Dental Pulp and Hard Tissues of the Tooth

The ability to consume a meal using one's own teeth influences an individual's quality of life. In today's global aging society, studying the biological changes in aging teeth is important to address this issue. A tooth includes three hard tissues (enamel, dentin, and cementum) and a soft tissue (dental pulp). With advancing age, these tissues become senescent; each tissue exhibits a unique senescent pattern. This review discusses the structural alterations of hard tissues, as well as the molecular and physiological changes in dental pulp cells and dental pulp stem cells during human aging. The significance of senescence in these cells remains unclear. Thus, there is a need to define the regulatory mechanisms of aging and senescence in these cells to aid in preservation of dental health.

Fucoidan from Fucus vesiculosus attenuates doxorubicin-induced acute cardiotoxicity by regulating JAK2/STAT3-mediated apoptosis and autophagy

Doxorubicin (DOX) is well-known for its potent antitumor activity but limited by its multiple and serious adverse effects. A major adverse effect is acute cardiotoxicity; yet, its mechanism has not been elucidated. Fucoidan is a multifunctional and nontoxic polysaccharide that is widely studied because of its favorable biological activities and safety. Hence, we proposed that fucoidan may play a protective role in DOX-induced acute cardiotoxicity without causing additional side effects. Sprague-Dawley rats were injected intraperitoneally with a single high dose of DOX to induce acute cardiac injury. Fucoidan was administered orally before DOX injection and AG490, a JAK2 inhibitor, was applied to verify the participation of the JAK2/STAT3 pathway. In vitro, H9C2 cells were treated with the same drugs at different concentrations and intervention times. in vivo and in vitro results demonstrated that DOX administration induced myocardial damage accompanied by acceleratory apoptosis and deficient autophagy in heart tissues or cells, which could be significantly improved by fucoidan supplement. AG490 partly abolished the cardioprotective effects of fucoidan, suggesting the involvement of JAK2 signaling. Additionally, western blotting revealed DOX-induced JAK2/STAT3 pathway activation, which was enhanced by fucoidan and weaken by AG490. Hence, fucoidan exerted a favorable effect on DOX-induced cardiotoxicity by enhancing autophagy and suppressing apoptosis in a JAK2/STAT3-dependent manner, which may provide a promising and novel therapeutic strategy against negative chemotherapy-induced effects.

Ginsenoside Rb1 Ameliorates Age-Related Myocardial Dysfunction by Regulating the NF-[Formula: see text]B Signaling Pathway

Age-related myocardial dysfunction is a very large healthcare burden. Here, we aimed to investigate whether ginsenoside Rb1 (Rb1) improves age-related myocardial dysfunction and to identify the relevant molecular mechanism. Young mice and aged mice were injected with Rb1 or vehicle for 3 months. Then, their cardiac function was inspected by transthoracic echocardiography. Serum and myocardium tissue were collected from all mice for histological or molecular expression analyses, including aging-related proteins, markers relevant to fibrosis and inflammation, and markers indicating the activation of the nuclear factor-kappa B (NF-[Formula: see text]B) pathway. Compared with the control condition, Rb1 treatment significantly increased the ejection fraction percentage and significantly decreased the internal diameter and volume of the left ventricle at the end-systolic and end-diastolic phases in aged mice. Rb1 treatment reduced collagen deposition and collagen I, collagen III, and transforming growth factor-[Formula: see text]1 protein expression levels in aged hearts. Rb1 also decreased the aging-induced myocardial inflammatory response, as measured by serum or myocardial interleukin-6 and tumor necrosis factor-[Formula: see text] levels. Furthermore, Rb1 treatment in aged mice increased cytoplasmic NF-[Formula: see text]B but decreased nuclear NF-[Formula: see text]B, which indicated the suppression of the NF-[Formula: see text]B signaling pathway by regulating the translocation of NF-[Formula: see text]B. Rb1 could alleviate aging-related myocardial dysfunction by suppressing fibrosis and inflammation, which is potentially associated with regulation of the NF-[Formula: see text]B signaling pathway.

Mitochondria-Targeting Antioxidant Provides Cardioprotection through Regulation of Cytosolic and Mitochondrial Zn2+ Levels with Re-Distribution of Zn2+-Transporters in Aged Rat Cardiomyocytes

Aging is an important risk factor for cardiac dysfunction. Heart during aging exhibits a depressed mechanical activity, at least, through mitochondria-originated increases in ROS. Previously, we also have shown a close relationship between increased ROS and cellular intracellular free Zn²⁺ ([Zn²⁺]_i) in cardiomyocytes under pathological conditions as well as the contribution of some re-expressed levels of Zn²⁺-transporters for redistribution of [Zn²⁺]_i among suborganelles. Therefore, we first examined the cellular (total) [Zn²⁺] and then determined the protein expression levels of Zn²⁺-transporters in freshly isolated ventricular cardiomyocytes from 24-month rat heart compared to those of 6-month rats. The [Zn²⁺]_i in the aged-cardiomyocytes was increased, at most, due to increased ZIP7 and ZnT8 with decreased levels of ZIP8 and ZnT7. To examine redistribution of the cellular [Zn²⁺]_i among suborganelles, such as Sarco/endoplasmic reticulum, S(E)R, and mitochondria ([Zn²⁺]_SER and [Zn²⁺]_Mit), a cell model (with galactose) to mimic the aged-cell in rat ventricular cell line H9c2 was used and demonstrated that there were significant increases in [Zn²⁺]_Mit with decreases in [Zn²⁺]_SER. In addition, the re-distribution of these Zn²⁺-transporters were markedly changed in mitochondria (increases in ZnT7 and ZnT8 with no changes in ZIP7 and ZIP8) and S(E)R (increase in ZIP7 and decrease in ZnT7 with no changes in both ZIP8 and ZnT8) both of them isolated from freshly isolated ventricular cardiomyocytes from aged-rats. Furthermore, we demonstrated that cellular levels of ROS, both total and mitochondrial lysine acetylation (K-Acetylation), and protein-thiol oxidation were significantly high in aged-cardiomyocytes from 24-month old rats. Using a mitochondrial-targeting antioxidant, MitoTEMPO (1 µM, 5-h incubation), we provided an important data associated with the role of mitochondrial-ROS production in the [Zn²⁺]_i-dyshomeostasis of the ventricular cardiomyocytes from 24-month old rats. Overall, our present data, for the first time, demonstrated that a direct mitochondria-targeting antioxidant treatment can be a new therapeutic strategy during aging in the heart through a well-controlled [Zn²⁺] distribution among cytosol and suborganelles with altered expression levels of the Zn²⁺-transporters.

Preventive Effects of Fucoidan and Fucoxanthin on Hyperuricemic Rats Induced by Potassium Oxonate

The purpose of this study was to investigate the preventive effects of fucoidan (Fc) and fucoxanthin (Fx) on hyperuricemic rats. Sprague Dawley (SD) rats were randomly assigned to seven groups: a control group, a hyperuricemia (HUA) group, low- and high-dose Fx groups, a Fc group, a combination Fc and Fx group, and a positive control group. Three weeks after the interventions, each group was given potassium oxonate (PO) and hypoxanthine (HX) to induce HUA in all groups except for the control group, and the rats were then sacrificed. Blood and urine were analyzed for biochemical properties, and differences in urine volume were determined. Livers and kidneys were collected to analyze xanthine oxidase (XO) activity and the expression of uric acid (UA) transporter-related proteins (GLUT9, ABCG2, OAT1, URAT1). The results show that HUA was successfully induced by PO/HX after 4 h of administration. The activity of XO was significantly reduced by a combination of Fc and Fx. In the combination group, both ABCG2 and OAT1 increased significantly, whereas GLUT9 and URAT1 decreased significantly. In summary, the combination of Fc and Fx can inhibit the activity of XO in the liver and regulate the expression of proteins related to UA transporter in the kidney to reduce the UA level in serum.

Development of Injectable Fucoidan and Biological Macromolecules Hybrid Hydrogels for Intra-Articular Delivery of Platelet-Rich Plasma

Platelet-rich plasma (PRP) is rich in growth factors and has commonly been utilized in the repair and regeneration of damaged articular cartilage. However, the major drawbacks of direct PRP injection are unstable biological fixation and fast or burst release of growth factors. Fucoidan is a heparinoid compound that can bind growth factors to control their release rate. Furthermore, fucoidan can reduce arthritis through suppressing inflammatory responses and thus it has been reported to prevent the progression of osteoarthritis, promote bone regeneration and accelerate healing of cartilage injury. Injectable hydrogels can be used to deliver cells and growth factors for an alternative, less invasive treatment of cartilage defects. In this study, hyaluronic acid (HA) and fucoidan (FD) was blended with gelatin (GLT) and the GLT/HA/FD hybrid was further cross-linked with genipin (GP) to prepare injectable GP-GLT/HA/FD hydrogels. The gelation rate was affected by the GP, GLT, HA and FD concentrations, as well as the pH values. The addition of HA and FD to GLT networks improved the mechanical strength of the hydrogels and facilitated the sustained release of PRP growth factors. The GP-GLT/HA/FD hydrogel showed adequate injectability, shape-persistent property and strong adhesive ability, and was more resistant to enzymatic degradation. The PRP-loaded GP-GLT/HA/FD hydrogel promoted cartilage regeneration in rabbits, which may lead to an advanced PRP therapy for enhancing cartilage repair.