Marine algae in regenerative medicine

Marine algae in regenerative medicine
Shima Mokhtari Garakani,^1,* Soha Mokhtari Garakani,²
Introduction: Marine algae are one of the most numerous resources in the ocean. They have been classified into 3 groups due to their natural chlorophylls and pigments which make their thallus colour. These groups are brown(Phaeophyta), green (Chlorophyta), and red (Rhodophyta) seaweeds. They are rich in polysaccharides and recent studies shows the high potentials of , marine algae polysaccharides (MAPs) in a wide range of health -promoting activities, such as regenerative medicine, wound dressing, tissue-engineering, 3D bioprinting , prebiotic, anti -oxidant, anti -bacterial, anti -inflammatory, and anti -cancer activities. Brown algae are rich in polysaccharides of the laminarin, alginate, and fucoidan types, with monosaccharide subunits such as glucose, rhamnose, galactose, fucose, xylose, mannose, glucuronic acid, and mannuronic acid. Red algae are rich in polysaccharides of the carrageenan, agar, and agarose types, which have a monosaccharide composition mainly composed of glucose, galactose, and 3,6 -anhydro -galactose . Green algae contain polysaccharides of the cellulose, mannan, sulfated rhamnan, and ulvan types, made up of monosaccharide subunits such as glucose, mannose, rhamnose, xylose, iduronic acid, and glucuronic acid.
Methods: Due to their unique structure resembling the human extracellular matrix, a wide spectrum of biological activities, high biocompatibility, biodegradability, low toxicity, renewability, significant moisture-retaining and swelling ability, and colloidal properties, Algae PS have found a wide range of applications in technologies of regenerative medicine, including the design of wound dressing materials. Wound healing is a multi-phase mechanism with various factors and cellular mediators. The use of conventional (standard) wound dressing materials, even those containing a drug, rarely provide successful wound healing, and deep and chronic wounds cannot be adequately treated with their use. Furthermore, the damage of bone tissues need the fixation or use of bone fillers. The use of biocompatible and biodegradable natural biopolymers derived from marine organisms, as promising materials for the development of innovative wound dressings, can be a comprehensive approach that takes into account the type and characteristics of a wound, the phase of wound healing, etc., thus, providing effective and complete healing within a shorter period of time.
Results: Current modern polymer-production technologies are also focused on the required physicochemical and biological properties of PS and synthetic polymers that provide opportunities for tissue-engineering technologies to be feasible in reconstructive and transplant surgery, the advanced delivery of drugs, growth factors, biologically active substances and tissue-engineering structures such as proteins, genes, cells, and implantable materials that are combined with tissue-engineering technologies. The wide range of biological activities of algae PS, their biocompatibility and biodegradability, gelling ability, hydrophilicity, and natural rigidity make them full-scale candidates to be used as biomaterials for the 3D bioprinting of tissues and organs. Tissue engineering is aimed at creating viable biological structures with the desirable spatial arrangement using three-dimensional (3D) bioprinting based on biocompatible materials (combinations of various biopolymers and synthetic polymers), which can also include living cells. The similarity of their structure with the human extracellular matrix and their inherent biological activity makes them viable for 3D bioprinting and other applications in tissue engineering. Many structures in the form of hydrogels, 3D-porous scaffolds, and nanofibers, which applications may vary from drug delivery to tissue-engineering purposes, have been developed on the basis of Polysaccharides. The target product of 3D bioprinting is implanted in the body, where it is completely dissolved and replaced by host tissues within a few months. The most studied compounds which were promising and have the potential to be used in these technologies are sulfated PS from various algae species (alginates and fucoidans from brown algae, carrageenans from red algae, and ulvans from green algae).
Conclusion: In vitro and in vivo mechanism studies are used to focus on the exhibition of physical, chemical, and biological activities under controlled environmental conditions. In vitro researches can entails laboratory -based mimics of one or more of the case encountered in the digestive tract such as the oral cavity, stomach, small intestine, and large intestine, while in vivo researches can continue at detailed descriptions of the mechanism of the digestion and fermentation behavior of MAPs.
Keywords: Marine algae, polysaccharides, wound dressing, tissue-engineering, 3D bioprinting