Pharmaceutically versatile sulfated polysaccharide based bionano platforms

Recent Advances in Multifaceted Drug Delivery Using Natural Polysaccharides and Polyacrylamide-based Nanomaterials in Nanoformulation

Rapid growth in nanotechnology, also known as 21st-century technology, is occurring in response to the increasing diversity of diseases. The development of safe and effective drug delivery methods to enhance bioavailability is of paramount importance. Researchers have focused on creating safe, cost-effective, and environmentally friendly nanoparticle construction processes. Natural polysaccharides, a type of multifaceted polymer with a wide range of applications and advantages, are particularly well suited for nanoparticle formulations, as they can mitigate the adverse consequences of synthetic nanoparticle formulations and promote sustainability. This review summarizes various sources of natural-based polysaccharides and polyacrylamide-based nanomaterials in nanoparticle preparation. Additionally, it discusses the use of natural polysaccharides in formulations beyond nanotechnology, highlighting their importance in green synthesis and different preparation methods.

Composite hydrogels assembled from food-grade biopolymers: Fabrication, properties, and applications

Biopolymer hydrogels have a broad range of applications as soft materials in a variety of commercial products, including foods, cosmetics, agrochemicals, personal care products, pharmaceuticals, and biomedical products. They consist of a network of entangled or crosslinked biopolymer molecules that traps relatively large quantities of water and provides semi-solid properties, like viscoelasticity or plasticity. Composite biopolymer hydrogels contain inclusions (fillers) to enhance their functional properties, including solid particles, liquid droplets, gas bubbles, nanofibers, or biological cells. These fillers vary in their composition, size, shape, rheology, and surface properties, which influences their impact on the rheological properties of the biopolymer hydrogels. In this article, the various types of biopolymers used to fabricate composite hydrogels are reviewed, with an emphasis on edible proteins and polysaccharides from sustainable sources, such as plants, algae, or microbial fermentation. The different kinds of gelling mechanism exhibited by these biopolymers are then discussed, including heat-, cold-, ion-, pH-, enzyme-, and pressure-set mechanisms. The different ways that biopolymer molecules can organize themselves in single and mixed biopolymer hydrogels are then highlighted, including polymeric, particulate, interpenetrating, phase-separated, and co-gelling systems. The impacts of incorporating fillers on the rheological properties of composite biopolymer hydrogels are then discussed, including mathematical models that have been developed to describe these effects. Finally, potential applications of composite biopolymer hydrogels are presented, including as delivery systems, packaging materials, artificial tissues, wound healing materials, meat analogs, filters, and adsorbents. The information provided in this article is intended to stimulate further research into the development and application of composite biopolymer hydrogels.

Dextran sulfate inhibits proliferation and metastasis of human gastric cancer cells via miR-34c-5p

Background

Gastric cancer (GC) is a malignant tumor with a high global mortality rate that is currently difficult to treat. Dextran sulfate (DS), a safe anti-tumor agent, can effectively inhibit the malignant biological behavior of gastric cancer; however, its mechanism of action is not fully understood. Therefore, this study aimed at elucidate the potential mechanisms of action.

Methods

In this study we used DS to intervene in lentivirus-transfected gastric cancer cells to observe the effect of DS on miR-34c-5p. RT-qPCR, CCK-8, clone formation assay, wound healing assay, transwell assay and western blot were used to examine whether DS affects the proliferation and metastasis of gastric cancer cells via miR-34c-5p. The results were validated using in vivo experiments.

Results

Our data confirmed that DS up-regulated miR-34c-5p expression in human gastric cancer cells. Moreover, DS intervention enhanced the inhibitory effect of miR-34c-5p over-expression on the proliferation, invasion, and migration of gastric cancer cells, and partially reversed the promotive effect of miR-34c-5p on the proliferation, invasion, and migration of gastric cancer cells. In addition, DS could affect the activation of the MAP2K1/ERK signaling pathway through the up-regulation of miR-34c-5p, thereby inhibiting the malignant biological behavior of gastric cancer. Finally, it was demonstrated that DS could also inhibit the expression of MAP2K1 in vivo, which in turn inhibits the activation of the ERK signaling pathway to exert anti-cancer effects.

Conclusion

DS may inhibit the proliferation and metastasis of gastric cancer cells by regulating miR-34c-5p, which may be a new option for clinical treatment.

Comprehensive review on recent trends and perspectives of natural exo-polysaccharides: Pioneering nano-biotechnological tools

Exopolysaccharides (EPSs), originating from various microbes, and mushrooms, excel in their conventional role in bioremediation to showcase diverse applications emphasizing nanobiotechnology including nano-drug carriers, nano-excipients, medication and/or cell encapsulation, gene delivery, tissue engineering, diagnostics, and associated treatments. Acknowledged for contributions to adsorption, nutrition, and biomedicine, EPSs are emerging as appealing alternatives to traditional polymers, for biodegradability and biocompatibility. This article shifts away from the conventional utility to delve deeply into the expansive landscape of EPS applications, particularly highlighting their integration into cutting-edge nanobiotechnological methods. Exploring EPS synthesis, extraction, composition, and properties, the discussion emphasizes their structural diversity with molecular weight and heteropolymer compositions. Their role as raw materials for value-added products takes center stage, with critical insights into recent applications in nanobiotechnology. The multifaceted potential, biological relevance, and commercial applicability of EPSs in contemporary research and industry align with the nanotechnological advancements coupled with biotechnological nano-cleansing agents are highlighted. EPS-based nanostructures for biological applications have a bright future ahead of them. Providing crucial information for present and future practices, this review sheds light on how eco-friendly EPSs derived from microbial biomass of terrestrial and aquatic environments can be used to better understand contemporary nanobiotechnology for the benefit of society.

Chondroitin sulfate modified calcium phosphate nanoparticles for efficient transfection via caveolin-mediated endocytosis

Efficient transfection remains a challenge for gene delivery in both cell biological scientific research and gene therapeutic fields. Existing transfection strategies rarely pay attention to altering the endocytosis pathway of nanocarriers for transfection efficiency improvement. In this work, we innovatively postulated that calcium phosphate nanoparticles coated with glycosaminoglycan could be internalized by cells mainly through caveolin-mediated endocytosis pathway allowing genes to bypass lysosome route, and hence enhance the transfection efficiency. To achieve this, we developed calcium phosphate nanoparticles (CP-ALN-CS) coated with chondroitin sulfate (CS) and alendronate (ALN) in a modular manner. The CP-ALN-CS had a hydrodynamic size of 131.0 ± 8.7 nm and exhibited favorable dispersity, stability, and resistance to nuclease degradation. Unlike conventional calcium phosphate and PEI-based transfection, CP-ALN-CS exhibited efficient cellular uptake with co-localization in Golgi apparatus and endoplasmic reticulum. Through bypassing the lysosome involved cellular uptake route, CP-ALN-CS can effectively protect genes from degradation and relieve cytotoxicity. After loading plasmid DNA, CP-ALN-CS showed extraordinary transfection efficiency in HEK 293T cells, outperforming the PEI which is considered as the gold standard. The current work provides a novel and facile approach to improve gene transfection efficiency and is valuable for the design of next-generation in vitro transfection reagents.

Nanotechnology-driven improvisation of red algae-derived carrageenan for industrial and bio-medical applications

Algae biomass has been recognized as feedstock with diverse application including production of biofuel, biofertilizer, animal feed, wastewater treatment and bioremediation. In addition, algae species are a potential reservoir of metabolites and polymers with potential to be utilized for biomedicine, healthcare and industrial purposes. Carrageenan is one such medicinally and industrially significant polysaccharide which is extracted from red algae species (Kappaphycus alvarezii and Eucheuma denticulatum, among the common species). The extraction process of carrageenan is affected by different environmental factors and the source of biomass, which can vary and significantly impact the yield. Diverse applications of carrageenan include hydrogel beads, bio-composites, pharmacological properties, application in cosmetics, food and related industries. Carrageenan biological activities including antioxidant, anti-inflammatory, antimicrobial, and antitumor activities are significantly influenced by sulfation pattern, yield percentage and molecular weight. In addition to natural biomedical potential of carrageenan, synergetic effect of carrageenan- nanocomposites exhibit potential for further improvisation of biomedical applications. Nanotechnology driven bio-composites of carrageenan remarkably improve the quality of films, food packaging, and drug delivery systems. Such nano bio-composites exhibit enhanced stability, biodegradability, and biocompatibility, making them suitable alternatives for drug delivery, wound-healing, and tissue engineering applications. The present work is a comprehensive study to analyze biomedical and other applications of Carrageenan along with underlying mechanism or mode of action along with synergetic application of nanotechnology.

Seaweed-Derived Sulfated Polysaccharides; The New Age Chemopreventives: A Comprehensive Review

Seaweed-derived bioactive compounds are regularly employed to treat human diseases. Sulfated polysaccharides are potent chemotherapeutic or chemopreventive medications since it has been discovered. They have exhibited anti-cancer properties by enhancing immunity and driving apoptosis. Through dynamic modulation of critical intracellular signalling pathways, such as control of ROS generation and preservation of essential cell survival and death processes, sulfated polysaccharides' antioxidant and immunomodulatory potentials contribute to their disease-preventive effectiveness. Sulfated polysaccharides provide low cytotoxicity and good efficacy therapeutic outcomes via dynamic modulation of apoptosis in cancer. Understanding how sulfated polysaccharides affect human cancer cells and their molecular involvement in cell death pathways will showcase a new way of chemoprevention. In this review, the significance of apoptosis and autophagy-modulating sulfated polysaccharides has been emphasized, as well as the future direction of enhanced nano-formulation for greater clinical efficacy. Moreover, this review focuses on the recent findings about the possible mechanisms of chemotherapeutic use of sulfated polysaccharides, their potential as anti-cancer drugs, and proposed mechanisms of action to drive apoptosis in diverse malignancies. Because of their unique physicochemical and biological properties, sulfated polysaccharides are ideal for their bioactive ingredients, which can improve function and application in disease. However, there is a gap in the literature regarding the physicochemical properties and functionalities of sulfated polysaccharides and the use of sulfated polysaccharide-based delivery systems in functional cancer. Furthermore, the preclinical and clinical trials will reveal the drug's efficacy in cancer.

Electrochemically Enhanced Delivery of Pemetrexed from Electroactive Hydrogels

Electroactive hydrogels based on derivatives of polyethyleneglycol (PEG), chitosan and polypyrrole were prepared via a combination of photopolymerization and oxidative chemical polymerization, and optionally doped with anions (e.g., lignin, drugs, etc.). The products were analyzed with a variety of techniques, including: FT-IR, UV-Vis, ¹H NMR (solution state), ¹³C NMR (solid state), XRD, TGA, SEM, swelling ratios and rheology. The conductive gels swell ca. 8 times less than the non-conductive gels due to the presence of the interpenetrating network (IPN) of polypyrrole and lignin. A rheological study showed that the non-conductive gels are soft (G' 0.35 kPa, G″ 0.02 kPa) with properties analogous to brain tissue, whereas the conductive gels are significantly stronger (G' 30 kPa, G″ 19 kPa) analogous to breast tissue due to the presence of the IPN of polypyrrole and lignin. The potential of these biomaterials to be used for biomedical applications was validated in vitro by cell culture studies (assessing adhesion and proliferation of fibroblasts) and drug delivery studies (electrochemically loading the FDA-approved chemotherapeutic pemetrexed and measuring passive and stimulated release); indeed, the application of electrical stimulus enhanced the release of PEM from gels by ca. 10-15% relative to the passive release control experiment for each application of electrical stimulation over a short period analogous to the duration of stimulation applied for electrochemotherapy. It is foreseeable that such materials could be integrated in electrochemotherapeutic medical devices, e.g., electrode arrays or plates currently used in the clinic.

Nanoplatforms for Irinotecan Delivery Based on Mesoporous Silica Modified with a Natural Polysaccharide

Natural compounds are an important source of beneficial components that could be used in cancer therapy along with well-known cytostatic agents to enhance the therapeutic effect while targeting tumoral tissues. Therefore, nanoplatforms containing mesoporous silica and a natural polysaccharide, ulvan, extracted from Ulva Lactuca seaweed, were developed for irinotecan. Either mesoporous silica-ulvan nanoplatforms or irinotecan-loaded materials were structurally and morphologically characterized. In vitro drug release experiments in phosphate buffer solution with a pH of 7.6 emphasized the complete recovery of irinotecan in 8 h. Slower kinetics were obtained for the nanoplatforms with a higher amount of natural polysaccharide. Ulvan extract proved to be biocompatible up to 2 mg/mL on fibroblasts L929 cell line. The irinotecan-loaded nanoplatforms exhibited better anticancer activity than that of the drug alone on human colorectal adenocarcinoma cells (HT-29), reducing their viability to 60% after 24 h. Moreover, the cell cycle analysis proved that the irinotecan loading onto developed nanoplatforms caused an increase in the cell number trapped at G0/G1 phase and influenced the development of the tumoral cells.

Three-Dimensional Bioprinting for Cartilage Tissue Engineering: Insights into Naturally-Derived Bioinks from Land and Marine Sources

In regenerative medicine and tissue engineering, the possibility to: (I) customize the shape and size of scaffolds, (II) develop highly mimicked tissues with a precise digital control, (III) manufacture complex structures and (IV) reduce the wastes related to the production process, are the main advantages of additive manufacturing technologies such as three-dimensional (3D) bioprinting. Specifically, this technique, which uses suitable hydrogel-based bioinks, enriched with cells and/or growth factors, has received significant consideration, especially in cartilage tissue engineering (CTE). In this field of interest, it may allow mimicking the complex native zonal hyaline cartilage organization by further enhancing its biological cues. However, there are still some limitations that need to be overcome before 3D bioprinting may be globally used for scaffolds' development and their clinical translation. One of them is represented by the poor availability of appropriate, biocompatible and eco-friendly biomaterials, which should present a series of specific requirements to be used and transformed into a proper bioink for CTE. In this scenario, considering that, nowadays, the environmental decline is of the highest concerns worldwide, exploring naturally-derived hydrogels has attracted outstanding attention throughout the scientific community. For this reason, a comprehensive review of the naturally-derived hydrogels, commonly employed as bioinks in CTE, was carried out. In particular, the current state of art regarding eco-friendly and natural bioinks' development for CTE was explored. Overall, this paper gives an overview of 3D bioprinting for CTE to guide future research towards the development of more reliable, customized, eco-friendly and innovative strategies for CTE.

Seaweed Phenolics as Natural Antioxidants, Aquafeed Additives, Veterinary Treatments and Cross-Linkers for Microencapsulation

Driven by consumer demand and government policies, synthetic additives in aquafeed require substitution with sustainable and natural alternatives. Seaweeds have been shown to be a sustainable marine source of novel bioactive phenolic compounds that can be used in food, animal and aqua feeds, or microencapsulation applications. For example, phlorotannins are a structurally unique polymeric phenolic group exclusively found in brown seaweed that act through multiple antioxidant mechanisms. Seaweed phenolics show high affinities for binding proteins via covalent and non-covalent bonds and can have specific bioactivities due to their structures and associated physicochemical properties. Their ability to act as protein cross-linkers means they can be used to enhance the rheological and mechanical properties of food-grade delivery systems, such as microencapsulation, which is a new area of investigation illustrating the versatility of seaweed phenolics. Here we review how seaweed phenolics can be used in a range of applications, with reference to their bioactivity and structural properties.

Eco-friendly extraction of Mastocarpus stellatus carrageenan for the synthesis of gold nanoparticles with improved biological activity

Carrageenan was extracted from Mastocarpus stellatus using hot water extraction under atmospheric and pressurized conditions. The influence of heating temperature during a non-isothermal heating profile up to temperatures in the range 70-190 °C was studied to evaluate the extraction yields and properties of the carrageenan fraction. Under the selected conditions (130 °C), extracted carrageenan (CMs) was used for the green synthesis of gold nanoparticles (AuNPs). After the optimization of the reaction conditions, the synthesized gold nanoparticles (Au@CMs) were characterized by UV-Vis spectroscopy, Z potential measurements, electron microscopy, and X-ray diffraction analysis, which confirmed the formation of spherical, polycrystalline, and negatively charged nanoparticles with a mean diameter of 14.3 ± 2.1 nm. The study conducted by scanning transmission electron microscopy, energy dispersive X-ray analysis and mapping confirmed the presence of carrageenan stabilizing AuNPs. Finally, Fourier transformed infrared spectroscopy was performed to analyze the functional groups of CMs involved in the reduction and stabilization of AuNPs. The selective cytotoxicity and the antioxidant activity of the Au@CMs were evaluated in different cell lines and compared to the CMs. Au@CMs showed an improved antioxidant capacity in cells under oxidative stress and the induction of apoptosis in a monocytic cell line, while no antitumor effect was observed in a lung endothelial cell line.

A comprehensive review on α-D-Glucans: Structural and functional diversity, derivatization and bioapplications

Glucans are the most abundant natural polysaccharides across the living kingdom with tremendous biological activities. Now a days, α-D-glucans are gaining importance as a prebiotics, nutraceuticals, immunostimulants, antiproliferative agents and biodegradable polymers in pharmaceutical and cosmetic sectors. A wide variety of bioresources including bacteria, fungi, lichens, algae, plants and animals produce α-D-glucans either as an exopolysaccharide (EPS) or a cell wall component or an energy storage polymer. The α-D-glucans exhibit great structural and functional diversity as the type of linkage and percentage of branching dictate the functional properties of glucans. Among the different linkages, bioactivities are greatly confined to the α-D-(1 → 3) linkages whereas starch and other polymers consisting of α-D-(1 → 4) (1 → 6) linkages are specific for food and pharmaceutical applications. However, the bioactivities of the α-D-(1 → 3) glucans in native form is limited mainly due to their hydrophobic nature. Hence several derivatization techniques have been developed to improve the bioavailability as well as bioactive features such as antiviral, antimicrobial, anti-inflammatory, antioxidant, immunomodulatory and antitumor properties. Though, several reports have presented about α-D-glucans, still there is an ambiguity in terms of their structure among different natural sources and moreover no comprehensive information was available on their derivatization techniques and application potential. Therefore, the present review summarizes distinct description on diverse sources, type of linkages, derivatization techniques as well as the application potential of the native and modified α-D-glucans.

In vitro biocompatibility screening of a colloidal gum Arabic-polyaniline conducting nanocomposite

Although polyaniline (PANI) is a widely investigated conductive polymer for biological applications, studies addressing the biocompatibility of colloidal PANI dispersions are scarcely found in the literature of the area. Therefore, PANI nanoparticles stabilized by the natural polysaccharide gum Arabic (GA) were screened for their biocompatibility. The GA successfully stabilized the colloidal PANI-GA dispersions when exposed to a protein-rich medium, showing compatibility with the biological environment. The results obtained from a series of in vitro assays showed that, after up to 48 h of exposure to a range of PANI-GA concentrations (1-50 μg/mL), both mouse BALB/3T3 fibroblasts and RAW 264.7 macrophages showed no evidence of change in cellular proliferation, viability and metabolic activity. An increase in macrophage granularity poses as evidence of phagocytic uptake of PANI-GA, without resulting activation of this cell type. Additionally, the PANI-GA nanoparticles modulated the cell morphology changes induced on fibroblasts by GA in a concentration-dependent manner. Thus, this unprecedented biocompatibility study of PANI nanoparticles stabilized by a plant gum exudate polysaccharide showed promising results. This simple biomaterial might be further developed into colloidal formulations for biological and biomedical applications, taking advantage of its versatility, biocompatibility, and conductive properties.

Structural sequencing and anti-inflammatory, anti-lung cancer activities of 1,4-α/β-sulfomalonoglucan in Antrodia cinnamomea

Antrodia cinnamomea is a precious Polyporaceous fungus with various bioactivities. This study reports the chemical identification and biological activities of sulfomalonoglucan, a sulfated polysaccharide (SPS), from the sodium sulfate enriched medium of the title fungus. The SPS-containing fraction was separated by gel filtration chromatography (GFC) to give the title SPS (denoted as Na10_SPS-F3). By analyzing the evidence for key inter-glycosidic linkages in the 1D and 2D NMR spectroscopic data, one possible repeat unit was proposed as: Na10_SPS-F3 inhibited the secretion of tumor necrosis factor (TNF-α) and interleukin (IL)-6 after lipopolysaccharide (LPS) stimulation in RAW264.7 macrophages. Mechanistically, Na10_SPS-F3 downregulated TGFRII also attenuated the LPS-induced IκB-α degradation. Moreover, Na10_SPS-F3 inhibited lung cancer cell H1975 EGFR/ERK signaling. This is the first paper reporting a 3-O-sulfomalonyl glucan (Na10_SPS-F3) with eight 1,4-β-Glc moieties connected with ten 1,4-α-Glc moieties from Antrodia cinnamomea and its anti-inflammatory and anti-cancer activities.

Carrageenan: Drug Delivery Systems and Other Biomedical Applications

Marine resources are today a renewable source of various compounds, such as polysaccharides, that are used in the pharmaceutical, medical, cosmetic, and food fields. In recent years, considerable attention has been focused on carrageenan-based biomaterials due to their multifunctional qualities, including biodegradability, biocompatibility, and non-toxicity, in addition to bioactive attributes, such as their antiviral, antibacterial, antihyperlipidemic, anticoagulant, antioxidant, antitumor, and immunomodulating properties. They have been applied in pharmaceutical formulations as both their bioactive and physicochemical properties make them suitable biomaterials for drug delivery, and recently for the development of tissue engineering. This article provides a review of recent research on the various types of carrageenan-based biomedical and pharmaceutical applications.

Porphyran-capped silver nanoparticles as a promising antibacterial agent and electrode modifier for 5-fluorouracil electroanalysis

In the present work, the green synthesis of silver nanoparticles (AgNPs) using the sulfated polysaccharide porphyran (PFR) as capping agent and d-glucose as reducing agent is described. PFR was extracted from red seaweed and characterized by employing ¹³C NMR and determination of total sugar, protein, and sulfate contents. The obtained AgNPs-PFR were characterized by using UV-VIS spectroscopy, zeta potential determination, FESEM, and TEM, which demonstrated that PFR was effective at capping the AgNPs, yielding stable suspensions. The AgNPs-PFR presented good antimicrobial properties against Gram-positive and Gram-negative bacterial strains (Staphylococcus aureus and Escherichia coli, respectively). The AgNPs-PFR were also employed as the modifier of carbon paste electrodes, which were efficiently applied as electrochemical sensors for the determination of 5-fluorouracil (5-FU), an important anticancer drug, through square wave voltammetry (SWV). The AgNPs-PFR improved the electrochemical properties of the electrodes, and enhanced their electroanalytical performance. The developed sensing device presented detection and quantification limits equal to 10.7 and 35.8 μmol L-1, respectively, towards 5-FU determination. The proposed electrochemical sensor successfully quantified 5-FU in a real pharmaceutical formulation, confirming its potential as a new promising analytical detection tool for 5-FU quality control purposes.

Chondroitin sulfate-hybridized zein nanoparticles for tumor-targeted delivery of docetaxel

Chondroitin sulfate-hybridized zein nanoparticles (zein/CS NPs) were developed for targeted delivery of docetaxel, which exhibited mean diameters of 157.8 ± 3.6 nm and docetaxel encapsulation efficiency of 64.2 ± 1.9 %. Docetaxel was released from the NPs in a sustained manner (∼72 h), following first-order kinetics. The zein/CS NPs showed improved colloidal stability, maintaining the initial size in serum for 12 h. The pre-treatment of CS reduced the uptake efficiency of the NPs by 23 % in PC-3 cells, suggesting the involvement of CD44-mediated uptake mechanism. The NPs showed 2.79-fold lower IC₅₀ values than free docetaxel. Enhanced tumor accumulation of the NPs was confirmed in PC-3 xenograft mice by near-infrared fluorescence imaging (35.3-fold, versus free Cy5.5). The NPs exhibited improved pharmacokinetic properties (9.5-fold longer terminal half-life, versus free docetaxel) and anti-tumor efficacy comparable to Taxotere with negligible systemic toxicity, suggesting zein/CS NPs could be a promising nanoplatform for targeted cancer therapy.

Disentangling the role of extracellular polysaccharides in desiccation tolerance in lichen-forming microalgae. First evidence of sulfated polysaccharides and ancient sulfotransferase genes

Trebouxia sp. TR9 and Coccomyxa simplex are desiccation-tolerant microalgae with flexible cell walls, which undergo species-specific remodelling during dehydration-rehydration (D/R) due to their distinct ultrastructure and biochemical composition. Here, we tested the hypothesis that extracellular polysaccharides excreted by each microalga could be quantitatively and/or qualitatively modified by D/R. Extracellular polysaccharides were analysed by size exclusion and anion exchange chromatography, specific stains after gel electrophoresis and gas chromatography/mass spectrometry of trimethylsilyl derivatives (to determine their monosaccharide composition). The structure of a TR9-sulfated polymer was deduced from nuclear magnetic resonance (NMR) analyses. In addition, sugar-sulfotransferase encoding genes were identified in both microalgae, and their expression was measured by RT-qPCR. D/R did not alter the polydispersed profile of extracellular polysaccharides in either microalga but did induce quantitative changes in several peaks. Furthermore, medium-low-sized uronic acid-containing polysaccharides were almost completely substituted by higher molecular mass carbohydrates after D/R. Sulfated polysaccharide(s) were detected, for the first time, in the extracellular polymeric substances of both microalgae, but only increased significantly in TR9 after cyclic D/R, which induced a sugar-sulfotransferase gene and accumulated sulfated ß-D-galactofuranan(s). Biochemical remodelling of extracellular polysaccharides in aeroterrestrial desiccation-tolerant microalgae is species-specific and seems to play a role in the response to changes in environmental water availability.

Current Designs and Developments of Fucoidan-based Formulations for Cancer Therapy

BACKGROUND

Natural nanostructure materials have been involved in antitumor drug delivery systems due to their biocompatibility, biodegradation, and bioactive properties.

METHODS

These materials have contributed to advanced drug delivery systems in the roles of both bioactive compounds and delivery nanocarriers. Fucoidan, a valuable ocean material used in drug delivery systems, has been exploited in research on cancer and a variety of other diseases.

RESULTS

Although the uniqueness, structure, properties, and health benefits of fucoidan have been mentioned in various prominent reviews, current developments and designs of fucoidan-based formulations still need to be assessed to further develop an effective anticancer therapy. In this review, current important formulations using fucoidan as a functional material and as an anticancer agent will be discussed. This article will also provide a brief principle of the methods that incorporate functional nanostructure materials in formulations exploiting fucoidan.

CONCLUSION

Current research and future perspectives on the use of fucoidan in anticancer therapy will advance innovative and important products for clinical uses.

Review on marine carbohydrate-based gold nanoparticles represented by alginate and chitosan for biomedical application

Gold nanoparticles (AuNPs) have been attracted considerable attention in cancer therapy, drug delivery and other applications due to their unique physical, chemical, and optical properties. Marine carbohydrates are important biological macromolecules that widely exist in marine algae and animals, such as alginate, carrageenan, porphyran, fucoidan, ulvan, agarose, and chitosan. Their excellent properties, such as biocompatibility, biodegradability and no irritation, make them widely used in biomedicine and nanomaterials fields. More importantly, they can be easily modified by functional groups, such as sulfation, acetylation, and carboxylation, to further extend their applications. The marine carbohydrates functionalized AuNPs can increase their biocompatibility and targeting in a green preparation method. Here, we review recent advances on marine carbohydrate-based AuNPs for cancer therapy, imaging, drug delivery and other biomedical fields. The topics of selective surface modification in different carbohydrates and further biomedical applications of AuNPs are also discussed.

Sulfated fucan/fucosylated chondroitin sulfate-dominated polysaccharide fraction from low-edible-value sea cucumber ameliorates type 2 diabetes in rats: New prospects for sea cucumber polysaccharide based-hypoglycemic functional food

Sulfated fucan chondroitin sulfate-dominated polysaccharide fraction from low-edible-value sea cucumber may be a good alternative to high-edible-value sea cucumber-derived polysaccharide for application in hypoglycemic functional foods. To evaluate the potential effect of low-edible-value sea cucumber-derived polysaccharide fraction on type 2 diabetes (T2DM), two sulfated fucan/fucosylated chondroitin sulfate-dominated polysaccharide fractions screening from 10 global commercial low-edible-value sea cucumber species were investigated to identify their anti-diabetics efficacies using a high-fat diet and streptozotocin-induced T2DM rat model. Sulfated fucan-dominated polysaccharide fraction from Thelenota ananas and fucosylated chondroitin sulfate-dominated polysaccharide fraction from Cucumaria frondosa ameliorated hyperglycemia, restored hypertriglyceridemia and hypercholesterolemia, decreased inflammatory status and oxidative stress, protected against liver injury, as well as improved insulin resistance and promoted accumulation of hepatic glycogen by activating IRS/PI3K/AKT signaling and regulating GSK-3β gene expression in T2DM rats. The current findings provide an available strategy for the commercialization of sea cucumber polysaccharide based-hypoglycemic functional food.

Effects of phytochemicals on cellular signaling: reviewing their recent usage approaches

Most of the previous studies in last three decades report evidence of interactions between the different phytochemicals and the proteins involved in signal transduction pathways using in silico, in vitro, ex vivo, and in vivo analyses. However, extrapolation of these findings for clinical purposes has not been that fruitful. The efficacy of the phytochemicals in vivo studies is limited by parameters such as solubility, metabolic degradation, excretion, etc. Various approaches have now been devised to circumvent these limitations. Recently, chemical modification of the phytochemicals are demonstrated to reduce some of the limitations and improve their efficacy. Similar to traditional medicines several combinatorial phytochemical formulations have shown to be more efficient. Further, phytochemicals have been reported to be even more efficient in the form of nanoparticles. However, systematic evaluation of their efficacy, mode of action in pathway modulation, usage and associated challenges is required to be done. The present review begins with basic understanding of how signaling cascades regulate cellular response and the consequences of their dysregulation further summarizing the developments and problems associated with the dietary phytochemicals and also discuss recent approaches in strengthening these compounds in pharmacological applications. Only context relevant studies have been reviewed. Considering the limitations and scope of the article, authors do not claim inclusion of all the early and recent studies.

Characterization and antitumor activity of the extracellular carbohydrate polymer from the cyanobacterium Synechocystis ΔsigF mutant

Cyanobacterial extracellular carbohydrate polymers are particularly attractive for biotechnological applications. Previously, we determined the monosaccharidic composition of the polymer of a Synechocystis ΔsigF overproducing mutant. Here, we further characterized this polymer, demonstrated that it is possible to recover it in high yields, and successfully use it for biomedical research. This amorphous polymer is formed by a mesh of fibrils/lamellar structures with high porosity, is constituted by high molecular mass fractions, is highly sulfated and displays low viscosity, even in highly concentrated aqueous solutions. FTIR analysis confirmed the presence of several functional groups. We demonstrated that the ΔsigF polymer has strong biological activity, decreasing the viability of melanoma, thyroid and ovary carcinoma cells by inducing high levels of apoptosis, through p53 and caspase-3 activation. Therefore, the ΔsigF Synechocystis mutant is a promising platform for the sustainable production of biological active carbohydrate polymer(s) with the desired characteristics for biomedical applications.

Ulvan, a bioactive marine sulphated polysaccharide as a key constituent of hybrid biomaterials: A review

Ulvan, a sulphated polysaccharide located in the cell walls of green algae that possesses unique structural properties albeit its repeating unit shares chemical affinity with glycosoaminoglycans, such as hyaluronan and chondroitin sulphate, has been increasingly studied over the years for applications in the pharmaceutical field. The increasing knowledge on ulvan's chemical properties and biological activities has triggered its utilization in hybrid materials, given its potential efficacy in biomedical applications. In the present review, the use of ulvan in the design of different biomaterials, including membranes, particles, hydrogels, 3D porous structures and nanofibers, is presented. The applications of these structures may vary from drug delivery to wound dressing or bone tissue engineering. In this context, general information regarding the structure and chemical variability, extraction processes, physicochemical properties, and biological activities of ulvan is reported.

Mechanical Stability of Lipid Membranes Decorated with Dextran Sulfate

Lipid vesicles decorated with polysaccharides have been proposed as vehicles for drug delivery because the polymers confer to the vesicles an enhanced stability, increasing the probability of the drug for reaching the target cell. Here, we first test the affinity of dextran sulfate (DS) for two different vesicle composition, and afterward, we study the effect of DS on the liposome mechanical properties. We found that DS binds to both tested membrane compositions. The interaction of DS with the anionic membranes studied here is mediated by the metal ions present in the aqueous solution (Na⁺ and Ca²⁺), being higher in the presence of Ca²⁺. Binding occurs preferentially in regions of closely packed lipids. Strikingly, DS did not affect the stability against detergent and the membrane rigidity of none of the vesicles. Thus, the proposed stability increase induced by this kind of polymers in drug delivery systems is not related with a modulation of the membrane thermodynamic properties but to other biochemical factors.

Smart Carriers and Nanohealers: A Nanomedical Insight on Natural Polymers

Biodegradable polymers are popularly being used in an increasing number of fields in the past few decades. The popularity and favorability of these materials are due to their remarkable properties, enabling a wide range of applications and market requirements to be met. Polymer biodegradable systems are a promising arena of research for targeted and site-specific controlled drug delivery, for developing artificial limbs, 3D porous scaffolds for cellular regeneration or tissue engineering and biosensing applications. Several natural polymers have been identified, blended, functionalized and applied for designing nanoscaffolds and drug carriers as a prerequisite for enumerable bionano technological applications. Apart from these, natural polymers have been well studied and are widely used in material science and industrial fields. The present review explains the prominent features of commonly used natural polymers (polysaccharides and proteins) in various nanomedical applications and reveals the current status of the polymer research in bionanotechnology and science sectors.

Sulfated Seaweed Polysaccharides as Multifunctional Materials in Drug Delivery Applications

In the last decades, the discovery of metabolites from marine resources showing biological activity has increased significantly. Among marine resources, seaweed is a valuable source of structurally diverse bioactive compounds. The cell walls of marine algae are rich in sulfated polysaccharides, including carrageenan in red algae, ulvan in green algae and fucoidan in brown algae. Sulfated polysaccharides have been increasingly studied over the years in the pharmaceutical field, given their potential usefulness in applications such as the design of drug delivery systems. The purpose of this review is to discuss potential applications of these polymers in drug delivery systems, with a focus on carrageenan, ulvan and fucoidan. General information regarding structure, extraction process and physicochemical properties is presented, along with a brief reference to reported biological activities. For each material, specific applications under the scope of drug delivery are described, addressing in privileged manner particulate carriers, as well as hydrogels and beads. A final section approaches the application of sulfated polysaccharides in targeted drug delivery, focusing with particular interest the capacity for macrophage targeting.