Insulin Carrier

PMN binding to and migration across endothelium initiates a sequence of events that resembles that following histamine treatment [14,30], namely, an increase in the permeability of the EC monolayer. For anionic plasma macromolecules, the plasmalemmal vesicles and transendothelial channels are suitable candidates for exit from the vessel lumen. Indeed, receptor-mediated transcytosis of insulin and transferrin has been identified for brain capillaries [31-33]. The insulin carriers have not yet been identified, but it is speculated that they could be coated vesicles and/or plasmalemmal vesicles. Transferrin [34] as well as ceruloplasmin [35,36] binding has been localized to coated pits and vesicles in the endothelium of bone marrow and liver capillary endothelium, respectively. 

M. J. Poznansky, R. Singh, B. Singh, and G. Fantus. Insulin carrier potential for enzyme and drug therapy. Science 223 1304 (1984). 

Alginate nanoparticles can be used as oral insulin carrier or glucose binder in the treatment of diabetes as a function of its chemical composition. High molecular weight M-rich alginate nanoparticles are a suitable vehicle for future development into oral insulin carrier (Kadir et al., 2013). 

Kadir, A., Mokhtar, M.T., Wong, T.W., 2013. Nanoparticulate assembly of mannuronic acid-and guluronic acid-rich alginate oral insulin carrier and glucose binder. J. Pharm. Sci. 102 (12), 4353 363. 

Transepithelial electrical resistance (TEER) measurements and transport smdies implied that CS/y-PGA NPs can be effective as an insulin carrier only in a limited area of the intestinal lumen where the pH values are close to the p/iTa of chitosan. So, a pH-responsive nanoparticle system was self-assembled by TMC and y-PGA for oral delivery of insulin. In contrast, TMC(40% Degree of Quatemisation) / y-PGA NPs may be a suitable carrier for transmucosal delivery of insulin within the entire intestinal tract. The loading efficiency and loading content of insulin in TMC/ y-PGA NPs were 73.8 2.9% and 23.5 2.1%, respectively. TMC/y-PGA NPs had superior stability in a broader pH range to CS/y-PGA NPs the in vitro release profiles of insulin from both test nanoparticles were significantly affected by their stability at distinct pH environments. TEER experiments showed that TMC/y-PGA NPs were able to open the tight junctions between Caco-2 cells, and this was further confirmed by confocal microscopy [66]. 

Insulin is commonly used in the treatment of diabetes mellitus. In the study carried out by Adresi and Yalcin [127] glutaraldehyde crosslinked agarose films were developed and examined as an insulin carrier. Swelling ratios and surface properties of agarose films were investigated for the characterization of the carrier materials. 

Ohya et al. reported poly(ethyleneglycol)-grafted chitosan nanoparticles as peptide drug carriers. The incorporation and release of insulin was dependent on the extent of the reaction of poly(ethyleneglycol) with chitosan [190]. 

It is not dependent upon insulin, unlike the corresponding carrier in muscle and adipose tissue. 

The concept of immunoassay was first described in 1945 when Landsteiner suggested that antibodies could bind selectively to small molecules (haptens) when they were conjugated to a larger carrier molecule. This hapten-specific concept was explored by Yalow and Berson in the late 1950s, and resulted in an immunoassay that was applied to insulin monitoring in humans. This pioneering work set the stage for the rapid advancement of immunochemical methods for clinical use. 

Since erythrocytes, platelets, and leukocytes have received the greatest attention, the discussion that follows will be limited to these carriers. Fibroblasts [180] and hepatocytes [181] have been specifically used as viable sources to deliver missing enzymes in the management of enzyme-deficiency diseases, whereas islets are useful as a cellular transplant to produce insulin [182,183],... 

Akiyoshi K, Kobayashi S, Shichibe S et al (1998) Self-assembled hydrogel nanoparticle of cholesterol-bearing pullulan as a carrier of protein drugs Complexation and stabilization of insulin. J Control Release 54 313-320... 

Fatty add synthase is a large multienzyme complex in the cytoplasm that is rapidly induced in the liver after a meal by high carbohydrate and the concomitant rise in insulin levels. It contains an acyl carrier protein (AGP) that requires the vitamin pantothenic add. Althoi malonyl CoA is the substrate used by fetty acid synthase, only the carbons from the acetyl CoA portion are actually incorporated into the fatty acid produced. Therefore, the fetty add is derived entirely from acetyl CoA. 

Mitchell, A., Pace, M., Numberger, J., et al. (2005) Insulin-mediated venodUation is impaired in young, healthy carriers of the 825T allele of the G-protein beta3 subunit gene (GNB3). Clin. 

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