Therapeutic potential of algal natural products against metabolic syndrome: A review of recent developments

The therapeutic potential of typical plant-derived compounds for the management of metabolic disorders

Obesity and Type 2 diabetes are prevalent metabolic dysfunctions that present significant health challenges worldwide. Available cures for these ailments have constraints with accompanying unwanted effects that persistently exist. Compounds originated from plants have recently been introduced as hopeful remedies to treat metabolic disorders because of their diverse pharmacological activities. This detailed observation gives an introduction into the treatment capacity of plant-derived compounds regarding metabolic syndromes while analyzing various groups alongside their performance in this field despite unique mechanisms designed by nature itself. Interestingly, this study provides some examples including curcumin, resveratrol, quercetin, berberine, epigallocatechin gallate (EGCG), and capsaicin, which highlights potential therapeutic impacts for future testing. However, current clinical trials inspecting human studies investigating efficacies concerning metabolism challenge present limitations. Finally, the review weighs up bad reactions possibly inflicted after administering plant-originated materials though suggestive insights will be provided later. Above all, it outlines the chance to identify novel therapies encapsulated within natural substances based upon recent developments could hold significant promise toward managing misplaced metabolisms globally.

Natural products for managing metabolic syndrome: a scoping review

Introduction

Metabolic syndrome comprises a collection of metabolic disorders stemming from factors like genetic predisposition, inadequate nutrition, stress, decreased physical activity, aging, and ethnicity. Although traditional pharmaceutical treatments exist for metabolic syndrome, their limited popularity is attributed to high costs and adverse effects. Consequently, natural products with fewer side effects have been explored for managing this condition. This literature review aims to explore the role of natural products including herbs, botanicals, vitamins, minerals, probiotics, and dietary supplements in managing metabolic syndrome.

Methods

This scoping review was conducted in five steps, involving the formulation of a research question, the retrieval and extraction of relevant studies, the selection of pertinent studies, the organization of information into tables, and the reporting of results. Data was collected from various databases including Embase, Science Direct, PubMed, Google Scholar, Scopus, and Web of Science, with a focus on studies published from 2010 to the present, available in English and with full-text accessibility.

Results

We identified 1,259 articles, screened their titles, abstracts, and full texts, ultimately incorporating 169 pertinent articles into this review (comprising 90 review articles, 32 trial articles, 6 in vitro articles, 38 in vivo articles, 1 experimental article and 2 observational articles). The study's outcomes revealed that natural products, encompassing plants and their derivatives, vitamins and supplements, as well as probiotics, can exert a beneficial influence on metabolic syndrome by regulating blood sugar, blood pressure, lipid profiles, obesity, and abnormal cholesterol and triglyceride levels.

Conclusion

The current study underscores the significance of natural products in addressing metabolic syndrome. Consequently, it is advisable to conduct further extensive research to assess the efficacy of these products, potentially integrating them into treatment regimens for individuals with metabolic syndrome.

Natural products for managing metabolic syndrome: a scoping review

Introduction

Metabolic syndrome comprises a collection of metabolic disorders stemming from factors like genetic predisposition, inadequate nutrition, stress, decreased physical activity, aging, and ethnicity. Although traditional pharmaceutical treatments exist for metabolic syndrome, their limited popularity is attributed to high costs and adverse effects. Consequently, natural products with fewer side effects have been explored for managing this condition. This literature review aims to explore the role of natural products including herbs, botanicals, vitamins, minerals, probiotics, and dietary supplements in managing metabolic syndrome.

Methods

This scoping review was conducted in five steps, involving the formulation of a research question, the retrieval and extraction of relevant studies, the selection of pertinent studies, the organization of information into tables, and the reporting of results. Data was collected from various databases including Embase, Science Direct, PubMed, Google Scholar, Scopus, and Web of Science, with a focus on studies published from 2010 to the present, available in English and with full-text accessibility.

Results

We identified 1,259 articles, screened their titles, abstracts, and full texts, ultimately incorporating 169 pertinent articles into this review (comprising 90 review articles, 32 trial articles, 6 in vitro articles, 38 in vivo articles, 1 experimental article and 2 observational articles). The study’s outcomes revealed that natural products, encompassing plants and their derivatives, vitamins and supplements, as well as probiotics, can exert a beneficial influence on metabolic syndrome by regulating blood sugar, blood pressure, lipid profiles, obesity, and abnormal cholesterol and triglyceride levels.

Conclusion

The current study underscores the significance of natural products in addressing metabolic syndrome. Consequently, it is advisable to conduct further extensive research to assess the efficacy of these products, potentially integrating them into treatment regimens for individuals with metabolic syndrome.

Seaweeds as Nutraceutical Elements and Drugs for Diabetes Mellitus: Future Perspectives

Diabetes mellitus is a chronic metabolic condition marked by high blood glucose levels caused by inadequate insulin synthesis or poor insulin use. This condition affects millions of individuals worldwide and is linked to a variety of consequences, including cardiovascular disease, neuropathy, nephropathy, and retinopathy. Diabetes therapy now focuses on controlling blood glucose levels through lifestyle changes, oral medicines, and insulin injections. However, these therapies have limits and may not successfully prevent or treat diabetic problems. Several marine-derived chemicals have previously demonstrated promising findings as possible antidiabetic medicines in preclinical investigations. Peptides, polyphenols, and polysaccharides extracted from seaweeds, sponges, and other marine species are among them. As a result, marine natural products have the potential to be a rich source of innovative multitargeted medications for diabetes prevention and treatment, as well as associated complications. Future research should focus on the chemical variety of marine creatures as well as the mechanisms of action of marine-derived chemicals in order to find new antidiabetic medicines and maximize their therapeutic potential. Based on preclinical investigations, this review focuses on the next step for seaweed applications as potential multitargeted medicines for diabetes, highlighting the bioactivities of seaweeds in the prevention and treatment of this illness.

Flavonoids, Isoflavonoids and others Bioactives for Insulin Sensitizations

Diabetes is a chronic condition that has an impact on a huge part of the world. Both animals and humans have been demonstrated to benefit from natural goods, and organisms (animals, or microbes). In 2021, approximately 537 million adults (20-79 years) are living with diabetes, making it the one of the biggest cause of death worldwide. Various phytoconstituent preserved β- cells activity helps to prevent the formation of diabetes problems. As a result, β-cells mass and function are key pharmaceutical targets. The purpose of this review is to provide an overview of flavonoids' effects on pancreatic β-cells. Flavonoids have been demonstrated to improve insulin release in cell lines of isolated pancreatic islets and diabetic animal models. Flavonoids are thought to protect β-cells by inhibiting nuclear factor-κB (NF-κB) signaling, activating the phosphatidylinositol 3-kinase (PI3K) pathway, inhibiting nitric oxide production, and lowering reactive oxygen species levels. Flavonoids boost β-cells secretory capacity by improving mitochondrial bioenergetic function and increasing insulin secretion pathways. Some of the bioactive phytoconstituents such as S-methyl cysteine sulfoxides stimulate insulin synthesis in the body and increase pancreatic output. The berberine increased insulin secretion in the HIT-T15 and Insulinoma 6 (MIN6) mouse cell line. Epigallocatechin-3-Gallate protects against toxicity accrued by cytokines, reactive oxygen species (ROS), and hyperglycemia. Quercetin has been proven to boost insulin production by Insulinoma 1 (INS-1) cells and also protect cell apoptosis. Overall flavonoids have beneficial effects on β-cells by prevented their malfunctioning or degradation and improving synthesis or release of insulin from β-cells.

Exploring cardiac impact of oral nicotine exposure in a transplantable Neoplasm Mice Model: Insights from biochemical analysis, morphometry, and molecular docking: Chlorella vulgaris green algae support

Nicotine-induced cardiac tissue damage is a concern for cancer patients, but the exact pathogenesis from nicotine oral exposure is unclear. This study was designed to investigate the impact of nicotine and Chlorella vulgaris (Ch. V) on cardiac glutathione homeostasis, inflammatory response, cardiac damage markers, apoptotic proteins and histopathological findings in an experimentally transplantable neoplasm mouse model (Ehrlich ascites carcinoma; EAC). In the in-vivo experiment, the female Swiss mice were divided into four groups: control, Ch.V (100 mg/kg), Nicotine (100 µg/ml/kg), and a combination group ( Nocotine+ Ch.V) for 40 days. Furthermore, in this study,the effects of C. vulgaris components on caspase-3, TNF-α, and IL-1β activity were explored using Molecular Operating Environment (MOE) docking software to ensure its ability to counteract the toxic effects of nicotine. The results indicated that nicotine has induced significant (P < 0.001) cardiopathic alterations in EAC-bearing mice with changes in cardiac tissue enzymes. C. Vulgaris attenuated the nicotine-induced cardiac glutathione inhibition, suppressed the inflammatory response, exerted antiapoptotic effects, mitigated myocardial injury biomarkers, and repaired cellular and tissue damage. Moreover, the molecular docking results revealed the ability of C. vulgaris to bind with interleukin-1 receptor type 1 (IL1R1) and tumor necrosis factor receptor superfamily member 1 A (TNFRSF1A) in the mice tissues, ameliorating apoptosis and inflammatory processes associated with nicotine-induced cardiotoxicity. This study provides a model for understanding nicotine-induced myocardial injury during experimentally transplantable neoplasm. It highlights C. vulgaris as a beneficial food supplement for cancer patients exposed to nicotine orally.

Algae-Derived Natural Products in Diabetes and Its Complications-Current Advances and Future Prospects

Diabetes poses a significant global health challenge, necessitating innovative therapeutic strategies. Natural products and their derivatives have emerged as promising candidates for diabetes management due to their diverse compositions and pharmacological effects. Algae, in particular, have garnered attention for their potential as a source of bioactive compounds with anti-diabetic properties. This review offers a comprehensive overview of algae-derived natural products for diabetes management, highlighting recent developments and future prospects. It underscores the pivotal role of natural products in diabetes care and delves into the diversity of algae, their bioactive constituents, and underlying mechanisms of efficacy. Noteworthy algal derivatives with substantial potential are briefly elucidated, along with their specific contributions to addressing distinct aspects of diabetes. The challenges and limitations inherent in utilizing algae for therapeutic interventions are examined, accompanied by strategic recommendations for optimizing their effectiveness. By addressing these considerations, this review aims to chart a course for future research in refining algae-based approaches. Leveraging the multifaceted pharmacological activities and chemical components of algae holds significant promise in the pursuit of novel antidiabetic treatments. Through continued research and the fine-tuning of algae-based interventions, the global diabetes burden could be mitigated, ultimately leading to enhanced patient outcomes.

Bioactivity of Macronutrients from Chlorella in Physical Exercise

Chlorella is a marine microalga rich in proteins and containing all the essential amino acids. Chlorella also contains fiber and other polysaccharides, as well as polyunsaturated fatty acids such as linoleic acid and alpha-linolenic acid. The proportion of the different macronutrients in Chlorella can be modulated by altering the conditions in which it is cultured. The bioactivities of these macronutrients make Chlorella a good candidate food to include in regular diets or as the basis of dietary supplements in exercise-related nutrition both for recreational exercisers and professional athletes. This paper reviews current knowledge of the effects of the macronutrients in Chlorella on physical exercise, specifically their impact on performance and recovery. In general, consuming Chlorella improves both anaerobic and aerobic exercise performance as well as physical stamina and reduces fatigue. These effects seem to be related to the antioxidant, anti-inflammatory, and metabolic activity of all its macronutrients, while each component of Chlorella contributes its bioactivity via a specific action. Chlorella is an excellent dietary source of high-quality protein in the context of physical exercise, as dietary proteins increase satiety, activation of the anabolic mTOR (mammalian Target of Rapamycin) pathway in skeletal muscle, and the thermic effects of meals. Chlorella proteins also increase intramuscular free amino acid levels and enhance the ability of the muscles to utilize them during exercise. Fiber from Chlorella increases the diversity of the gut microbiota, which helps control body weight and maintain intestinal barrier integrity, and the production of short-chain fatty acids (SCFAs), which improve physical performance. Polyunsaturated fatty acids (PUFAs) from Chlorella contribute to endothelial protection and modulate the fluidity and rigidity of cell membranes, which may improve performance. Ultimately, in contrast to several other nutritional sources, the use of Chlorella to provide high-quality protein, dietary fiber, and bioactive fatty acids may also significantly contribute to a sustainable world through the fixation of carbon dioxide and a reduction of the amount of land used to produce animal feed.

Structural diversity, biosynthesis, and health-promoting properties of brown algal meroditerpenoids

Marine algae that constitute hundreds of millions of tons of biomass are the oldest representatives of the plant kingdom. Recently, there has been growing interest in the utilization of algae as sustainable feedstocks for natural products with an economic value. Among these natural products are the meroditerpenoids, which are renowned for their protective effects against oxidative stress, inflammation, cancer, obesity, diabetes, and neurodegenerative disorders. Meroditerpenoids have a mixed biosynthetic origin and display a wide range of structural diversity. Their basic structure consists of a ring system bearing a diterpenoid side chain. Structural variations are observed in terms of the functional groups and saturation/cyclization of the diterpenoid side chain. This review classifies algal meroditerpenoids as plastoquinones, chromanols, chromenes, chromones, cyclic meroditerpenoids, nahocols, and isonahocols and examines their potential applications in functional foods and biopharmacology. Their lipid solubility, low molecular weight, and propensity to cross the blood-brain barrier places meroditerpenoids as potential drug candidates. There is growing interest in the study of algal meroterpenoids, and recent research has reported the structure of several new meroterpenoids and their biological activities. Further research is needed to extend the use of algal meroditerpenoids in preclinical trials. Understanding the mechanism of their biosynthesis will allow the development of de novo biosynthesis and biomimetic synthesis strategies for the industrial-scale production of meroditerpenoids and their synthetic derivatives to aid pharmaceutical research. This review is the first to summarize up-to-date information on all brown algae-derived meroditerpenoids.

Effects of a Mealworm (Tenebrio molitor) Extract on Metabolic Syndrome-Related Pathologies: In Vitro Insulin Sensitivity, Inflammatory Response, Hypolipidemic Activity and Oxidative Stress

The mealworm (Tenebrio molitor Linnaeus 1758) is gaining importance as one of the most popular edible insects. Studies focusing on its bioactivities are increasing, although alternative forms of consumption other than the whole insect or flour, such as bioactive non-protein extracts, remain underexplored. Furthermore, the incidence of metabolic syndrome-related pathologies keeps increasing, hence the importance of seeking novel natural sources for reducing the impact of certain risk factors. The aim was to study the potential of a non-protein mealworm extract on metabolic syndrome-related pathologies, obtained with ethanol:water (1:1, v/v) by ultrasound-assisted extraction. We characterized the extract by gas-chromatography mass-spectrometry and assessed its hypolipidemic potential, its ability to scavenger free radicals, to attenuate the inflammatory response in microglial cells, to affect mitochondrial respiration and to enhance insulin sensitivity in mouse hepatocytes. The extract contained fatty acids, monoglycerides, amino acids, certain acids and sugars. The mealworm extract caused a 30% pancreatic lipase inhibition, 80% DPPH· scavenging activity and 55.9% reduction in the bioaccessibility of cholesterol (p = 0.009). The extract was effective in decreasing iNOS levels, increasing basal, maximal and ATP coupled respiration as well as enhancing insulin-mediated AKT phosphorylation at low insulin concentrations (p < 0.05). The potential of a non-protein bioactive mealworm extract against metabolic syndrome-related pathologies is shown, although further studies are needed to elucidate the mechanisms and relationship with compounds.

Mechanistic insights into the inhibitory activities of chemical constituents from the fruits of Terminalia boivinii on α-glucosidase

Regulation of key digestive enzymes is currently considered an effective remedy for diabetes mellitus. In this study, bioactive constituents were purified from Terminalia boivinii fruits and identified by 1 H NMR, 13 C NMR and EI-MS. In vitro and in silico methods were used to evaluate α-glucosidase, α-amylase, and lipase inhibition activities. Compounds 1 , 2 , and 4-7 with IC50 values between 89 and 445 µM showed stronger α-glucosidase inhibitory activities than the antihyperglycemic drug acarbose (IC 50 =1463.0 ± 29.5 µM). However, the compounds showed lower inhibitory effects against α-amylase and lipase with IC 50 values above 500 µM than acarbose (IC 50 = 16.7 ± 3.5 µM) and ursolic acid (IC 50 = 89.5 ± 5.6 µM), respectively. Lineweaver-Burk plots showed that compounds 1 , 2 , and 7 were non-competitive inhibitors, compounds 4 and 5 were competitive inhibitors and compound 6 was a mixed-type inhibitor. Fluorescence spectroscopic data showed that the compounds altered the microenvironment and conformation of α-glucosidase. Computer simulations indicated that the compounds and enzyme interacted primarily through hydrogen bonding. The findings indicated that the compounds were inhibitors of α-glucosidase and provided significant structural basis for understanding the binding activity of the compounds with α-glucosidase.

Algae: Study of Edible and Biologically Active Fractions, Their Properties and Applications

The beneficial properties of algae make them perfect functional ingredients for food products. Algae have a high energy value and are a source of biologically active substances, proteins, fats, carbohydrates, vitamins, and macro- and microelements. They are also rich in polyunsaturated fatty acids, proteins, mycosporine-like amino acids, polysaccharides, polyphenols, carotenoids, sterols, steroids, lectins, halogenated compounds, polyketides, alkaloids, and carrageenans. Different extraction parameters are used depending on the purpose and the substances to be isolated. In this study, the following parameters were used: hydromodule 1:10 and an extraction duration of 1-2 h at the extraction temperature of 25-40 °C. A 30-50% solution of ethanol in water was used as an extractant. Algae extracts can be considered as potential natural sources of biologically active compounds with antimicrobial activity and antiviral properties. The content of crude protein, crude fat, and carbohydrates in U. Prolifera, C. racemosa var. peltata (Chlorophyta), S. oligocystum and S. fusiforme (SF-1) was studied. It was found that C. muelleri (Bacillariophyta), I. galbana (Haptophyta), and T. weissflogii (Bacillariophyta) contain about 1.9 times more omega-3 than omega-6 fatty acids. N. gaditana (Ochrophyta), D. salina (Chlorophyta), P. tricornutum (Bacillaryophyta) and I. galbana (Haptophyta) extracts showed inhibitory activity of varying intensities against E. coli or P. aeruginosa. In addition, algae and algae-derived compounds have been proposed to offer attractive possibilities in the food industry, especially in the meat sector, to evolve functional foods with myriad functionalities. Algae can increase the biological activity of food products, while the further study of the structure of compounds found in algae can broaden their future application possibilities.

Marine algal flavonoids and phlorotannins; an intriguing frontier of biofunctional secondary metabolites

Algae are the oldest representatives of the plant world with reserves exceeding hundreds of millions of tons in the world's oceans. Currently, a growing interest is placed toward the use of algae as feedstocks for obtaining numerous natural products. Algae are a rich source of polyphenols that possess intriguing structural diversity. Among the algal polyphenols, phlorotannins, which are unique to brown seaweeds, and have immense value as potent modulators of biochemical processes linked to chronic diseases. In algae, flavonoids remain under-explored compared to other categories of polyphenols. Both phlorotannins and flavonoids are inclusive of compounds indicating a wide structural diversity. The present paper reviews the literature on the ecological significance, biosynthesis, structural diversity, and bioactivity of seaweed phlorotannins and flavonoids. The potential implementation of these chemical entities in functional foods, cosmeceuticals, medicaments, and as templates in drug design are described in detail, and perspectives are provided to tackle what are perceived to be the most momentous challenges related to the utilization of phlorotannins and flavonoids. Moving beyond: industrial biotechnology applications, metabolic engineering, total synthesis, biomimetic synthesis, and chemical derivatization of phlorotannins and flavonoids could broaden the research perspectives contributing to the health and economic up-gradation.

Therapeutic Potential of Seaweed-Derived Bioactive Compounds for Cardiovascular Disease Treatment

Cardiovascular diseases are closely related to hypertension, type 2 diabetes mellitus, obesity, and hyperlipidemia. Many studies have reported that an unhealthy diet and sedentary lifestyle are critical factors that enhance these diseases. Recently, many bioactive compounds isolated from marine seaweeds have been studied for their benefits in improving human health. In particular, several unique bioactive metabolites such as polyphenols, polysaccharides, peptides, carotene, and sterol are the most effective components responsible for these activities. This review summarizes the current in vitro, in vivo, and clinical studies related to the protective effects of bioactive compounds isolated from seaweeds against cardiovascular disorders, including anti-diabetic, anti-hypertensive, anti-hyperlipidemia, and anti-obesity effects. Therefore, this present review summarizes these concepts and provides a basis for further in-depth research.

Unravelling the promise and limitations of CRISPR/Cas system in natural product research: Approaches and challenges

An incredible array of natural products are produced by plants that serve several ecological functions, including protecting them from herbivores and microbes, attracting pollinators, and dispersing seeds. In addition to their obvious medical applications, natural products serve as flavouring agents, fragrances and many other uses by humans. With the increasing demand for natural products and the development of various gene engineering systems, researchers are trying to modify the plant genome to increase the biosynthetic pathway of the compound of interest or blocking the pathway of unwanted compound synthesis. The clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 has had widespread success in genome editing due to the system's high efficiency, ease of use, and accuracy which revolutionized the genome editing system in living organisms. This article highlights the method of the CRISPR/Cas system, its application in different organisms including microbes, algae, fungi and also higher plants in natural product research, its shortcomings and future prospects. This article is protected by copyright. All rights reserved.

Supercritical fluid extraction (SCFE) as green extraction technology for high-value metabolites of algae, its potential trends in food and human health

Application of high-value algal metabolites (HVAMs) in cosmetics, additives, pigments, foods and medicines are very important. These HVAMs can be obtained from the cultivation of micro- and macro-algae. These metabolites can benefit human and animal health in a physiological and nutritional manner. However, because of conventional extraction methods and their energy and the use of pollutant solvents, the availability of HVAMs from algae remains insufficient. Receiving their sustainability and environmental benefits have recently made green extraction technologies for HVAM extractions more desirable. But very little information is available about the technology of green extraction of algae from these HVAM. This review, therefore, highlights the supercritical fluid extraction (SCFE) as principal green extraction technologyand theirideal parameters for extracting HVAMs. In first, general information is provided concerning the HVAMs and their components of macro and micro origin. The review also includes a description of SCFE technology's properties, instrumentation operation, solvents used, and the merits and demerits. Moreover, there are several HVAMs associated with their numerous high-level biological activities which include high-level antioxidant, anti-inflammatory, anticancer and antimicrobial activity and have potential health-beneficial effects in humans since they are all HVAMs, such as foods and nutraceuticals. Finally, it provides future insights, obstacles, and suggestions for selecting the right technologies for extraction.

Dieckol induces cell cycle arrest by down-regulating CDK2/cyclin E in response to p21/p53 activation in human tracheal fibroblasts

The phlorotannin derivative dieckol isolated from Ecklonia cava has been shown to exhibit anti-inflammatory, anti-bacterial, anti-oxidative anti-adipogenic and anti-stenosis activity. However, the role of dieckol in cyclin-dependent kinase 2 (CDK2)/cyclin E signalling, which regulates fibrosis development, has not yet been determined. In this study, we report that dieckol-suppressed cell proliferation through the cell cycle arrest of Hs680.Tr human tracheal fibroblasts. Following consecutive purification, dieckol was identified as a potent bioactive compound. The results showed that dieckol had significant anti-proliferative activity against Hs680.Tr human tracheal fibroblastsWestern blotting analysis also found that dieckol dose-dependently induced the cell cycle arrest of Hs680.Tr fibroblasts in the G0/G1 phase, accompanied by the downregulation of CDK2 and cyclin E and the upregulation of p21 and p53. As attested by molecular docking study, the dieckol interacted with the core interface residues in transforming growth factor-β receptor with high affinity. These findings suggest that dieckol from E. cava inhibits the cell proliferation of Hs680.Tr, potentially through p21- and p53-mediated G0/G1 cell cycle arrest.

A Comprehensive Review about the Molecular Structure of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2): Insights into Natural Products against COVID-19

In 2019, the world suffered from the emergence of COVID-19 infection, one of the most difficult pandemics in recent history. Millions of confirmed deaths from this pandemic have been reported worldwide. This disaster was caused by SARS-CoV-2, which is the last discovered member of the family of Coronaviridae. Various studies have shown that natural compounds have effective antiviral properties against coronaviruses by inhibiting multiple viral targets, including spike proteins and viral enzymes. This review presents the classification and a detailed explanation of the SARS-CoV-2 molecular characteristics and structure-function relationships. We present all currently available crystal structures of different SARS-CoV-2 proteins and emphasized on the crystal structure of different virus proteins and the binding modes of their ligands. This review also discusses the various therapeutic approaches for COVID-19 treatment and available vaccinations. In addition, we highlight and compare the existing data about natural compounds extracted from algae, fungi, plants, and scorpion venom that were used as antiviral agents against SARS-CoV-2 infection. Moreover, we discuss the repurposing of select approved therapeutic agents that have been used in the treatment of other viruses.

Screening of in vitro and in silico α-amylase, α-glucosidase, and lipase inhibitory activity of oxyprenylated natural compounds and semisynthetic derivatives

Metabolic syndrome has several characteristic manifestations, including insulin resistance and dyslipidaemia, that demand therapeutic approaches, such as the inhibition of enzymes involved in nutrient absorption and digestion.This study aimed to evaluate the potential pharmacological use of natural compounds widespread in the plant kingdom and their semisynthetic compounds against target enzymes. Twenty-three oxyprenylated natural compoundswere investigated for their ability to inhibit α-amylase, α-glucosidase, and pancreatic lipase enzymes by in vitro assays. Moreover, in silico molecular docking was performed to analyse their binding capabilities into 3D structures. Farnesyloxyferulic acid, geranyloxyvanillic acid, nelumal A, and geranyloxyferulic acid showed the highest inhibition activity in all three in vitro enzyme assays. Moreover, in silico molecular docking of these four compounds was used to analyse their possible binding in 3D structures of the investigated enzymes. The results indicate that these compounds have considerable therapeutic potential for the treatment of metabolic syndrome, and further studies are warranted for their pharmacological development.

Potential applications of algae in biochemical and bioenergy sector

Algae have gained substantial importance as the most promising potential green fuel source across the globe and is on growing demand due to their antioxidant, anticancer, antiviral, antihypertensive, cholesterol reducing and thickening properties. Therefore, it has vast range of application in medicines, pharmaceutical, cosmetics, paper and nutraceutical industries. In this work, the remarkable ability of algae to convert CO₂ and other toxic compounds in atmosphere to potential biofuels, foods, feeds and high-value bioactive compounds is reviewed. Algae produce approximately 50% of the earth's oxygen using its photosynthetic activity, thus acting as a potent tool to mitigate the effects of air pollution. Further, the applicability of algae as a desirable energy source has also been discussed, as they have the potential to serve as an effective alternative to intermittent renewable energy; and also, to combustion-based fossil fuel energy, making them effective for advanced biofuel conversions. This work also evaluates the current applications of algae and the implications of it as a potential substrate for bioplastic, natural alternative to inks and for making paper besides high-value products. In addition, the scope for integrated biorefinery approach is also briefly explored in terms of economic aspects at the industrial scale, as such energy conversion mechanisms are directly linked with sustainability, thus providing a positive overall energy outlook.

Using polyphenols as a relevant therapy to diabetes and its complications, a review

Diabetes is currently a worldwide health concern. Hyperglycemia, hypertension, obesity, and oxidative stress are the major risk factors that inevitably lead to all the complications from diabetes. These complications severely impact the quality of life of patients, and they can be managed, reduced, or even reverted by several polyphenols, plant extracts and foods rich in these compounds. The goal of this review is to approach diabetes not as a single condition but rather an interconnected combination of risk factors and complications. This work shows that polyphenols have multi target action and effects and they have been systematically proven to be relevant in the reduction of each risk factor and improvement of associated complication.

Edible Microalgae and Their Bioactive Compounds in the Prevention and Treatment of Metabolic Alterations

Marine and freshwater algae and their products are in growing demand worldwide because of their nutritional and functional properties. Microalgae (unicellular algae) will constitute one of the major foods of the future for nutritional and environmental reasons. They are sources of high-quality protein and bioactive molecules with potential application in the modern epidemics of obesity and diabetes. They may also contribute decisively to sustainability through carbon dioxide fixation and minimization of agricultural land use. This paper reviews current knowledge of the effects of consuming edible microalgae on the metabolic alterations known as metabolic syndrome (MS). These microalgae include Chlorella, Spirulina (Arthrospira) and Tetraselmis as well as Isochrysis and Nannochloropsis as candidates for human consumption. Chlorella biomass has shown antioxidant, antidiabetic, immunomodulatory, antihypertensive, and antihyperlipidemic effects in humans and other mammals. The components of microalgae reviewed suggest that they may be effective against MS at two levels: in the early stages, to work against the development of insulin resistance (IR), and later, when pancreatic -cell function is already compromised. The active components at both stages are antioxidant scavengers and anti-inflammatory lipid mediators such as carotenoids and -3 PUFAs (eicosapentaenoic acid/docosahexaenoic acid; EPA/DHA), prebiotic polysaccharides, phenolics, antihypertensive peptides, several pigments such as phycobilins and phycocyanin, and some vitamins, such as folate. As a source of high-quality protein, including an array of bioactive molecules with potential activity against the modern epidemics of obesity and diabetes, microalgae are proposed as excellent foods for the future. Moreover, their incorporation into the human diet would decisively contribute to a more sustainable world because of their roles in carbon dioxide fixation and reducing the use of land for agricultural purposes.

Diphlorethohydroxycarmalol Isolated from Ishige okamurae Exerts Vasodilatory Effects via Calcium Signaling and PI3K/Akt/eNOS Pathway

Nitric oxide (NO) is released by endothelial cells in the blood vessel wall to enhance vasodilation. Marine polyphenols are known to have protective effects against vascular dysfunction and hypertension. The present study is the first to investigate how diphlorethohydroxycarmalol (DPHC) isolated from Ishige okamurae affects calcium levels, resulting in enhanced vasodilation. We examined calcium modulation with the well-known receptors, acetylcholine receptor (AchR) and vascular endothelial growth factor 2 (VEGFR2), which are related to NO formation, and further confirmed the vasodilatory effect of DPHC. We confirmed that DPHC stimulated NO production by increasing calcium levels and endothelial nitric oxide synthase (eNOS) expression. DPHC affected AchR and VEGFR2 expression, thereby influencing transient calcium intake. Specific antagonists, atropine and SU5416, were used to verify our findings. Furthermore, based on the results of in vivo experiments, we treated Tg(flk:EGFP) transgenic zebrafish with DPHC to confirm its vasodilatory effect. In conclusion, the present study showed that DPHC modulated calcium transit through AchR and VEGFR2, increasing endothelial-dependent NO production. Thus, DPHC, a natural marine component, can efficiently ameliorate cardiovascular diseases by improving vascular function.

Clinical Efficacy of Brown Seaweeds Ascophyllum nodosum and Fucus vesiculosus in the Prevention or Delay Progression of the Metabolic Syndrome: A Review of Clinical Trials

Metabolic syndrome (MetS) is a global public health problem affecting nearly 25.9% of the world population characterised by a cluster of disorders dominated by abdominal obesity, high blood pressure, high fasting plasma glucose, hypertriacylglycerolaemia and low HDL-cholesterol. In recent years, marine organisms, especially seaweeds, have been highlighted as potential natural sources of bioactive compounds and useful metabolites, with many biological and physiological activities to be used in functional foods or in human nutraceuticals for the management of MetS and related disorders. Of the three groups of seaweeds, brown seaweeds are known to contain more bioactive components than either red and green seaweeds. Among the different brown seaweed species, Ascophyllum nodosum and Fucus vesiculosus have the highest antioxidant values and highest total phenolic content. However, the evidence base relies mainly on cell line and small animal models, with few studies to date involving humans. This review intends to provide an overview of the potential of brown seaweed extracts Ascophyllum nodosum and Fucus vesiculosus for the management and prevention of MetS and related conditions, based on the available evidence obtained from clinical trials.

Brown Seaweeds for the Management of Metabolic Syndrome and Associated Diseases

Metabolic syndrome is characterized by the coexistence of different metabolic disorders which increase the risk of developing type 2 diabetes mellitus and cardiovascular diseases. Therefore, metabolic syndrome leads to a reduction in patients' quality of life as well as to an increase in morbidity and mortality. In the last few decades, it has been demonstrated that seaweeds exert multiple beneficial effects by virtue of their micro- and macronutrient content, which could help in the management of cardiovascular and metabolic diseases. This review aims to provide an updated overview on the potential of brown seaweeds for the prevention and management of metabolic syndrome and its associated diseases, based on the most recent evidence obtained from in vitro and in vivo preclinical and clinical studies. Owing to their great potential for health benefits, brown seaweeds are successfully used in some nutraceuticals and functional foods for treating metabolic syndrome comorbidities. However, some issues still need to be tackled and deepened to improve the knowledge of their ADME/Tox profile in humans, in particular by finding validated indexes of their absorption and obtaining reliable information on their efficacy and long-term safety.

Mechanisms of Bioactivities of Fucoidan from the Brown Seaweed Fucus vesiculosus L. of the Barents Sea

The aim of this study was to elucidate some mechanisms of radical scavenging and the anti-inflammatory, anti-hyperglycemic, and anti-coagulant bioactivities of high molecular weight fucoidan from Fucus vesiculosus in several in vitro models. Fucoidan has displayed potent 1, 1-diphenyl-2-picryl hydrazil radical scavenging and reduction power activities. It significantly inhibits the cyclooxygenase-2 (COX-2) enzyme (IC₅₀ 4.3 μg mL⁻¹) with a greater selectivity index (lg(IC₈₀ COX-2/IC₈₀COX-1), −1.55) than the synthetic non-steroidal anti-inflammatory drug indomethacin (lg(IC₈₀ COX-2/IC₈₀COX-1), −0.09). A concentration-dependent inhibition of hyaluronidase enzyme with an IC₅₀ of 2.9 μg mL⁻¹ was observed. Fucoidan attenuated the lipopolysaccharide-induced expression of mitogen-activated protein kinase p38. Our findings suggest that the inhibition of dipeptidyl peptidase-IV (DPP-IV) (IC₅₀ 1.11 μg mL⁻¹) is one of the possible mechanisms involved in the anti-hyperglycemic activity of fucoidan. At a concentration of 3.2 μg mL⁻¹, fucoidan prolongs the activated partial thromboplastin time and thrombin time by 1.5-fold and 2.5-fold compared with a control, respectively. A significant increase of prothrombin time was observed after the concentration of fucoidan was increased above 80 μg mL⁻¹. This evidenced that fucoidan may have an effect on intrinsic/common pathways and little effect on the extrinsic mechanism. This study sheds light on the multiple pathways of the bioactivities of fucoidan. As far as we know, the inhibition of hyaluronidase and DPP-IV by high molecular fucoidan was studied for the first time in this work. Our results and literature data suggest that molecular weight, sulfate content, fucose content, and polyphenols may contribute to these activities. It seems that high molecular weight fucoidan has promising therapeutic applications in different pharmacological settings. Anti-oxidant, anti-inflammatory and anti-coagulant drugs have been used for the management of complications of COVID19. Taken as a whole, fucoidan could be considered as a prospective candidate for the treatment of patients with COVID19; however, additional research in this field is required.