New Trends of the Polysaccharides as a Drug

Polysaccharides (PSs) may be regarded as key ingredients for the production of bio-based materials in life sciences (medical devices, pharmaceutics, food and cosmetics). There are an enormous variety of polysaccharides that can be synthesized and/or released by marine algae. Both these marine organisms are excellent sources of PSs, most of them sulfated (S-PSs). Although some similarities may be found between the PSs from each group of organisms, they can be very heterogeneous and structurally different. The biological source and biodegradability of these biopolymers, coupled to the large variety of functionalities they encompass, make them promising compounds for the application in pharmaceuticals, therapeutics, and regenerative medicine. Some of the beneficial bioactivities demonstrated by the crude PSs and their derivatives, either in-vitro or in-vivo, include anticoagulant and/or antithrombotic properties, immunomodulatory ability, anti-tumor and cancer preventive activity. They are also good antilipidemic and hypoglycemic agents, and can be powerful antioxidants, antibiotics and anti-inflammatory. Other biomedical properties of PSs have been discussed, such as antinociceptive, angiogenic, cardioprotective, gastroprotective and hepatoprotective activities. The biomedical applications and potentialities of PSs in this area were listed, such as healing wound agents, mucobioadhesives for bone and soft tissue closure, bio lubricants to mitigate joint disorders caused by arthritis, vaccines for cancer immunotherapy, or in a new generation of bio textiles and medical fibers, in drug delivery systems, and scaffolds in regenerative medicine. From the extensive list above, the importance of this type of PSs from algae for medical use is quite obvious. However, despite all the interesting properties and potentialities for human health, the use of these PSs, especially those from algae need to be further explored. In particular, the toxicity and bioavailability of some of these polymers are yet to be studied on humans.