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.

Exploration of Toxins from a Marine Annelid: An Analysis of Phyllotoxins and Accompanying Bioactives

Proteinaceous toxins are peptides or proteins that hold great biotechnological value, evidenced by their ecological role, whether as defense or predation mechanisms. Bioprospecting using bioinformatics and omics may render screening for novel bioactives more expeditious, especially considering the immense diversity of toxin-secreting marine organisms. Eulalia sp. (Annelida: Phyllodocidae), a toxin bearing marine annelid, was recently shown to secrete cysteine-rich protein (Crisp) toxins (hitherto referred to as 'phyllotoxins') that can immobilize its prey. By analyzing and validating transcriptomic data, we narrowed the list of isolated full coding sequences of transcripts of the most abundant toxins or accompanying bioactives secreted by the species (the phyllotoxin Crisp, hyaluronidase, serine protease, and peptidases M12A, M13, and M12B). Through homology matching with human proteins, the biotechnological potential of the marine annelid's toxins and related proteins was tentatively associated with coagulative and anti-inflammatory responses for the peptidases PepM12A, SePr, PepM12B, and PepM13, and with the neurotoxic activity of Crisp, and finally, hyaluronidase was inferred to bear properties of an permeabilizing agent. The in silico analysis succeeded by validation by PCR and Sanger sequencing enabled us to retrieve cDNAs can may be used for the heterologous expression of these toxins.

An Exploration of Novel Bioactives from the Venomous Marine Annelid Glycera alba

The immense biodiversity of marine invertebrates makes them high-value targets for the prospecting of novel bioactives. The present study investigated proteinaceous toxins secreted by the skin and proboscis of Glycera alba (Annelida: Polychaeta), whose congenerics G. tridactyla and G. dibranchiata are known to be venomous. Proteomics and bioinformatics enabled the detection of bioactive proteins that hold potential for biotechnological applications, including toxins like glycerotoxins (GLTx), which can interfere with neuromuscular calcium channels and therefore have value for the development of painkillers, for instance. We also identified proteins involved in the biosynthesis of toxins. Other proteins of interest include venom and toxin-related bioactives like cysteine-rich venom proteins, many of which are known to interfere with the nervous system. Ex vivo toxicity assays with mussel gills exposed to fractionated protein extracts from the skin and proboscis revealed that fractions potentially containing higher-molecular-mass venom proteins can exert negative effects on invertebrate prey. Histopathology, DNA damage and caspase-3 activity suggest significant cytotoxic effects that can be coadjuvated by permeabilizing enzymes such as venom metalloproteinases M12B. Altogether, these encouraging findings show that venomous annelids are important sources of novel bioactives, albeit illustrating the challenges of surveying organisms whose genomes and metabolisms are poorly understood.

Algal Phycocolloids: Bioactivities and Pharmaceutical Applications

Seaweeds are abundant sources of diverse bioactive compounds with various properties and mechanisms of action. These compounds offer protective effects, high nutritional value, and numerous health benefits. Seaweeds are versatile natural sources of metabolites applicable in the production of healthy food, pharmaceuticals, cosmetics, and fertilizers. Their biological compounds make them promising sources for biotechnological applications. In nature, hydrocolloids are substances which form a gel in the presence of water. They are employed as gelling agents in food, coatings and dressings in pharmaceuticals, stabilizers in biotechnology, and ingredients in cosmetics. Seaweed hydrocolloids are identified in carrageenan, alginate, and agar. Carrageenan has gained significant attention in pharmaceutical formulations and exhibits diverse pharmaceutical properties. Incorporating carrageenan and natural polymers such as chitosan, starch, cellulose, chitin, and alginate. It holds promise for creating biodegradable materials with biomedical applications. Alginate, a natural polysaccharide, is highly valued for wound dressings due to its unique characteristics, including low toxicity, biodegradability, hydrogel formation, prevention of bacterial infections, and maintenance of a moist environment. Agar is widely used in the biomedical field. This review focuses on analysing the therapeutic applications of carrageenan, alginate, and agar based on research highlighting their potential in developing innovative drug delivery systems using seaweed phycocolloids.

Marine Macroalgae Polyphenols as Potential Neuroprotective Antioxidants in Neurodegenerative Diseases

Polyphenols are beneficial natural compounds with antioxidant properties that have recently gain a lot of interest for their potential therapeutic applications. Marine polyphenols derived from marine macroalgae have been discovered to possess interesting antioxidant properties; therefore, these compounds can be included in several areas of drug development. Authors have considered the use of polyphenol extracts from seaweeds as neuroprotective antioxidants in neurodegenerative diseases. Marine polyphenols may slow the progression and limit neuronal cell loss due to their antioxidant activity; therefore, the use of these natural compounds would improve the quality of life for patients affected with neurodegenerative diseases. Marine polyphenols have distinct characteristics and potential. Among seaweeds, brown algae are the main sources of polyphenols, and present the highest antioxidant activity in comparison to red algae and green algae. The present paper collects the most recent in vitro and in vivo evidence from investigations regarding polyphenols extracted from seaweeds that exhibit neuroprotective antioxidant activity. Throughout the review, oxidative stress in neurodegeneration and the mechanism of action of marine polyphenol antioxidant activity are discussed to evidence the potential of algal polyphenols for future use in drug development to delay cell loss in patients with neurodegenerative disorders.

Effect of the alveolate parasite Perkinsus olseni infection on sexual maturation and spawning efficiency of the clam Ruditapes decussatus

The effect of Perkinsus olseni infection on the reproduction ability of clams has been underestimated so far. Although some studies found evidence of reduction of egg production and delay in gonad maturation after infection, the total effect of the infection is still unclear. In this study, Ruditapes decussatus clams from a naïve population were injected with two different doses of P. olseni parasites, a low dose leading to a light infection and a high dose leading to a heavy infection. Clams were maintained during 2 months for maturation, and at the end of the experiment, the spawning was induced, the number of larvae release and mortality were evaluated. During the maturation period, infection level, gonadal stage, condition index, gross biochemical composition and oxidative status of progenitors were evaluated at days 0, 30 and 60 post-injection. The effects of P. olseni infection on clams showed alterations on biochemical parameters, namely lipid peroxidation, a significant mortality and a delayed gonad maturation, with a greater effect in the highly infected individuals. The reproductive capacity of the clams was impaired in both infected groups showing a lower production and a higher mortality rate of larvae. Finally, this study indicates that the production of natural beds with a high prevalence of P. olseni could be compromised by a deregulation of the natural reproduction cycle and a decrease in larvae production by infected animals, probably due to a combination of lower egg production and lower lipid reserves in larvae from infected clams.

Call the Eckols: Present and Future Potential Cancer Therapies

In recent years, an increased interest in marine macroalgae bioactive compounds has been recorded due to their benefits to human health and welfare. Several of their bioactivities have been demonstrated, such as anti-inflammatory, antioxidant, anticarcinogenic, antibacterial and antiviral behavior. However, there still lacks a clear definition regarding how these compounds exert their bioactive properties. Of all the bioactive compounds derived from marine macroalgae, attention has been focused on phenolic compounds, specifically in phlorotannins, due to their potential for biomedical applications. Phlorotannins are a diverse and wide group of phenolic compounds, with several structural variations based on the monomer phloroglucinol. Among the diverse phlorotannin structures, the eckol-family of phlorotannins demonstrates remarkable bioactivity, notably their anti-tumoral properties. However, the molecular mechanisms by which this activity is achieved remain elusive and sparse. This review focuses on the described molecular mechanisms of anti-tumoral effects by the eckol family of compounds and the future prospects of these molecules for potential application in oncology therapies.

An Overview to the Health Benefits of Seaweeds Consumption

Currently, seaweeds are gaining major attention due to the benefits they give to our health. Recent studies demonstrate the high nutritional value of seaweeds and the powerful properties that seaweeds' bioactive compounds provide. Species of class Phaeophyceae, phylum Rhodophyta and Chlorophyta possess unique compounds with several properties that are potential allies of our health, which make them valuable compounds to be involved in biotechnological applications. In this review, the health benefits given by consumption of seaweeds as whole food or by assumption of bioactive compounds trough natural drugs are highlighted. The use of seaweeds in agriculture is also highlighted, as they assure soils and crops free from chemicals; thus, it is advantageous for our health. The addition of seaweed extracts in food, nutraceutical, pharmaceutical and industrial companies will enhance the production and consumption/usage of seaweed-based products. Therefore, there is the need to implement the research on seaweeds, with the aim to identify more bioactive compounds, which may assure benefits to human and animal health.