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Role of marine polysaccharides in treatment of metabolic disorders
Published in Antonio Trincone, Enzymatic Technologies for Marine Polysaccharides, 2019
Manigandan Venkatesan, Velusamy Arumugam, Rathinam Ayyasamy, Karthik Ramachadran, Subhapradha Namasivayam, Umamaheswari Sundaresan, Archunan Govindaraju, Ramachandran Saravanan
Glycosaminoglycans (GAGs) are heteropolysaccharides with repeating units of disaccharide and consist mainly of an amino sugar (N-acetylgalactosamine or N-acetylglucosamine) and uronic acid. It is present on the surface of the extracellular matrix of almost all animal cells, through which it binds and regulates different kinds of proteins, growth factors, and cytokines for normal metabolic activity. GAGs are generally generated from mammalian tissues mainly from slaughterhouse [e.g., rooster combs, cartilage (tracheas and nasal from bovine and swine) and umbilical cords]. However, the prevalence of bovine spongiform encephalopathy and other food chain crises will eventually lead to the exploration of other sources such as microbes and marine organisms. Among the marine diversity, mollusks, squid, sea cucumbers, sponges, cartilaginous material from shark, salmon, and ray fish are potential source of GAGs (Seno and Mayer 1963; Kinoshita-Toyoda et al. 2004). The effects of GAGs have been analyzed on the type 2 diabetic mice model by administering chitosan with intraperitoneal injection of streptozotocin and maintaining the mice on a high-sugar, high-lipid diet. Treatment with GAGs from the marine worm Urechis unicinctus reversed the damage on islet of β cell and restored its function. GAGs from U. unicinctus has potent hypoglycemic activity and has the ability to improve the antioxidant mechanism of diabetic mice; improves glucose tolerance, liver glycogen content, and insulin sensitivity index; and also repairs liver and pancreatic tissue (Yuan et al. 2015). Albuminuria in type 1 and type 2 diabetic patients is significantly improved when treated with GAGs and with sulodexide (Abaterusso and Gambaro 2006). Administration with GAGs, such as low molecular weight heparin and dermatan sulfate in diabetic rats, prevents both glomerular basement membrane thickening and anionic charge density reduction in the glomerular basement membrane and sustains urinary excretion of albumin at normal levels without affecting the metabolic control of the disease (Gambaro et al. 1992). Administration with insulin prevents renal lesions in diabetic rats and controls glycemia (Rasch 1979), even in the absence of insulin treatment; animals administered with GAGs showed good results (Gambaro et al. 1992). Administration of GAGs can prevent some of the morphological and physiological alterations that occur in experimental diabetic nephropathy. In 1994, Gambaro and coworkers proved that the long-term administration of GAGs prevents morphological and functional alterations of renal tissue in diabetic rats and reversed the condition of established diabetic renal lesions. GAG administration modified renal matrix composition by the normalization of collagen gene expression and increasing glomerular 35S-sulfate incorporation.
Combination of engineering the substrate and Ca2+ binding domains of heparinase I to improve the catalytic activity
Published in Preparative Biochemistry & Biotechnology, 2023
Hua-Ping Zhou, Ding-Ran Wang, Chen-Lu Xu, Ye-Wang Zhang
Heparin lyases, also named as heparinases, first identified from Pedobacter heparinus,[1] which cleave heparin and heparan sulfate at the glycosidic bond between hexosamine and uronic acid through β-elimination mechanism.[2,3] Heparin lyases are classified as heparinase I (EC 4.2.2.7), heparinase II (no EC number), and heparinase III (EC 4.2.2.8). Of the three kinds of heparinases, heparinase I is the widest used enzyme in their essential industrial and clinical applications. Since it can be used to analyze the structures of heparin and heparin-like glycosaminoglycan (GAG),[4,5] it can also be the candidate for the neutralization of heparin in human blood[6–8] and production of low molecular weight heparin (LMWH).[9,10] Meanwhile, one of the advantages of heparinase I degradation reactions is that they are milder and can be performed without complications of competing side-reactions associated with conventional chemical decomposition.[11]
Green in the deep blue: deep eutectic solvents as versatile systems for the processing of marine biomass
Published in Green Chemistry Letters and Reviews, 2022
Colin McReynolds, Amandine Adrien, Natalia Castejon, Susana C. M. Fernandes
Chondroitin sulfate is a polysaccharide of the glycosaminoglycan family, made up of repeating disaccharide units of glucuronic acid and N-acetylgalactosamine linked by β-(1→3) glycosidic bonds and sulfated in different carbon positions. It is an essential component of an extracellular matrix of connective tissues, which plays a central role in diverse biological processes (114). It is commonly extracted from both terrestrial and marine sources, composition and concentration depending on organism and tissue. Uses of chondroitin sulfate are predominantly centered around medical/nutraceutical use as treatment for osteoarthritis (115) although new uses are emerging for tissue engineering (116). Classically, shark and ray fins have been the most commonly used to produce these molecules, although stock management is problematic for the long-term sustainability of these sources (117).
Heparin conjugated PCL/Gel – PCL/Gel/n-HA bilayer fibrous membrane for potential regeneration of soft and hard tissues
Published in Journal of Biomaterials Science, Polymer Edition, 2020
Jie Liu, Qin Zou, Bin Cai, Jiawei Wei, Chen Yuan, Yubao Li
Surface modification of electrospun fibers of biodegradable aliphatic polyesters can be achieved by plasma treatment and chemical hydrolysis, which will result in the generation of oxygen-based functional groups, such as carboxyl, carbonyl and hydroxyl groups. These functional groups benefit for further immobilization of bioactive molecules that could enhance cellular interactions such as cell adhesion and proliferation [20, 21]. Heparin is a highly sulfated glycosaminoglycan and possesses strong binding affinity (electrostatic interaction) to a variety of growth factors [22], this is why some researchers have devised a number of ways to conjugate heparin on scaffolds or protein delivery carriers [23, 24]. Therefore, we plan to use heparin to conjugate the bilayer membrane to further improve the biological properties.