Fucoidan Immobilized at the Surface of a Fibrous Mesh Presents Toxic Effects over Melanoma Cells, But Not over Noncancer Skin Cells

Comparative Bioactivities of Chemically Modified Fucoidan and λ-Carrageenan toward Cells Encapsulated in Covalently Cross-Linked Hydrogels

The sulfated marine polysaccharides, fucoidan and λ-carrageenan, are known to possess anti-inflammatory, immunomodulatory, and cellular protective properties. Although they hold considerable promise for tissue engineering constructs, their covalent cross-linking in hydrogels and comparative bioactivities to cells are absent from the literature. Thus, fucoidan and λ-carrageenan were modified with methacrylate groups and were covalently cross-linked with the synthetic polymer poly(vinyl alcohol)-methacrylate (PVA-MA) to form 20 wt % biosynthetic hydrogels. Identical degrees of methacrylation were confirmed by 1H NMR, and covalent conjugation was determined by using a colorimetric 1,9-dimethyl-methylene blue (DMMB) assay. Pancreatic beta cells were encapsulated in the hydrogels, followed by culturing in the 3D environment for a prolonged period of 32 days and evaluation of the cellular functionality by live/dead, adenosine 5'-triphosphate (ATP) level, and insulin secretion. The results confirmed that fucoidan and λ-carrageenan exhibited ∼12% methacrylate substitution, which generated hydrogels with stable conjugation of the polysaccharides with PVA-MA. The cells encapsulated in the PVA-fucoidan hydrogels demonstrated consistently high ATP levels over the culture period. Furthermore, only cells in the PVA-fucoidan hydrogels retained glucose responsiveness, demonstrating comparatively higher insulin secretion in response to glucose. In contrast, cells in the PVA-λ-carrageenan and the PVA control hydrogels lost all glucose responsiveness. The present work confirms the superior effects of chemically modified fucoidan over λ-carrageenan on pancreatic beta cell survival and function in covalently cross-linked hydrogels, thereby illustrating the importance of differential polysaccharide structural features on their biological effects.

Biomedical potency and mechanisms of marine polysaccharides and oligosaccharides: A review

Derived from bountiful marine organisms (predominantly algae, fauna, and microorganisms), marine polysaccharides and marine oligosaccharides are intricate macromolecules that play a significant role in the growth and development of marine life. Recently, considerable attention has been paid to marine polysaccharides and marine oligosaccharides as auspicious natural products due to their promising biological attributes. Herein, we provide an overview of recent advances in the miscellaneous biological activities of marine polysaccharides and marine oligosaccharides that encompasses their anti-cancer, anti-inflammatory, antibacterial, antiviral, antioxidant, anti-diabetes mellitus, and anticoagulant properties. Furthermore, we furnish a concise summary of the underlying mechanisms governing the behavior of these biological macromolecules. We hope that this review inspires research on marine polysaccharides and marine oligosaccharides in medicinal applications while offering fresh perspectives on their broader facets.

Marine-Inspired Drugs and Biomaterials in the Perspective of Pancreatic Cancer Therapies

Despite its low prevalence, pancreatic cancer (PC) is one of the deadliest, typically characterised as silent in early stages and with a dramatically poor prognosis when in its advanced stages, commonly associated with a high degree of metastasis. Many efforts have been made in pursuing innovative therapeutical approaches, from the search for new cytotoxic drugs and other bioactive compounds, to the development of more targeted approaches, including improved drug delivery devices. Marine biotechnology has been contributing to this quest by providing new chemical leads and materials originating from different organisms. In this review, marine biodiscovery for PC is addressed, particularly regarding marine invertebrates (namely sponges, molluscs, and bryozoans), seaweeds, fungi, and bacteria. In addition, the development of biomaterials based on marine-originating compounds, particularly chitosan, fucoidan, and alginate, for the production of advanced cancer therapies, is also discussed. The key role that drug delivery can play in new cancer treatments is highlighted, as therapeutical outcomes need to be improved to give further hope to patients.

Electrospinning: New Strategies for the Treatment of Skin Melanoma

Recent studies have shown a significant growth of skin cancer cases in northern regions of the world, in which its presence was not common. Skin cancer is one of the cancers that mostly affects the world's population, ranking fifth in studies conducted in the United States (USA). Melanoma is cancer that has the highest number of deaths worldwide since it is the most resistant skin cancer to current treatments. This is why alternatives for its treatment has been investigated considering nanomedicine concepts. This study approaches the role of this field in the creation of promising electrospun devices, composed of nanoparticles and nanofibers, among other structures, capable of directing and/or loading active drugs and/or materials with the objective of inhibiting the growth of melanoma cells or even eliminating those cells.

Transdermal nanotherapeutics: Panax quinquefolium polysaccharide nanoparticles attenuate UVB-induced skin cancer

Ultraviolet (UV) radiation is known to cause an imbalance of the endogenous antioxidant system leading to an increase in skin cancer. Panax quinquefolium (American ginseng) polysaccharides (GPS) can inhibit such an imbalance due to its anti-oxidative and anti-inflammatory properties. The aim of this study was to investigate the therapeutic effects of topical formulations containing GPS nanoparticles (NPs) to inhibit UVB induced oxidative damage and skin cancer. Photoaging was conducted under UVB irradiation with a dose of 300 mJ/cm2 on SKH1 hairless mice. The treatment groups (n = 5) were as follows: sham control, native GPS, GPS NPs and fluorescent labeled GPS NPs. To compare the photoprotective performance, the topical formulations were applied before and after UVB induction (pre-treatment and post-treatment), followed by sacrificing the animals. Then, skin and blood samples were collected, and inflammatory cytokines production was measured using ELISA. Compared to the sham control, GPS NPs pre-treated mice skin and blood samples exhibited a significant lowering in all cytokine production. In addition, skin histology analysis showed that pre-treatment of GPS NPs prevented epidermal damage and proliferation. The results support that topical formulation containing GPS NPs can inhibit UVB induced oxidative damage and skin cancer.

Angiogenic potential of airbrushed fucoidan/polycaprolactone nanofibrous meshes

Implantation of biomaterials and hybrid constructs in tissue engineering approaches presents major limitations such as inflammatory reaction and the lack of vasculature integration. Therefore, new strategies are needed to enhance implant function, immune protection, and revascularization. In this work, we developed fibrous meshes composed of fucoidan (Fu), a sulfated polysaccharide extracted from brown algae, and polycaprolactone (PCL), a synthetic biodegradable polymer, using the airbrush technique. The chemical characterization by FTIR, EDS, and XPS confirmed the presence of the two polymers in the structure of airbrushed nanofibrous meshes (ANFM). Moreover, these nanofibrous exhibited good wettability and mechanical properties envisaging their application as templates for biomaterials and cell culture. The developed ANFM were directly cultured with human pulmonary microvascular endothelial (HPMEC-ST1.6R) cells for up to 7 days. Biological results demonstrated that ANFM comprising Fu promoted cellular attachment, spreading, and proliferation of human endothelial cells. The angiogenic potential of ANFM was further evaluated by onplantation of PCL and PCL/Fu ANFM in chick chorioallantoic membrane (CAM). In ovo and ex ovo results showed that the incorporation of Fu increased the pro-angiogenic potential of ANFM. Altogether, the results suggest that airbrush biocomposite meshes could be used as a biomaterial substrate to promote vascularization.