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Schipper, Nicolaas; Vårum, Kjell M.; Artursson, Per

doi:10.1023/a:1016444808000

Cited by 346 publications

(76 citation statements)

References 16 publications

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“…Toxicity was found to be degree of deacetylation and molecular weight dependent. At high DD the toxicity is related to the molecular weight and the concentration, at lower DD toxicity is less pronounced and less related to the molecular weight [93].…”

Section: Safe Biomaterialsmentioning

confidence: 96%

Is Chitosan a New Panacea? Areas of Application

Castro¹,

Paulín²

2012

The Complex World of Polysaccharides

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Chitin is a big molecule composed of -beta-1,4-N-acetylglucosamine (GlcNAc) monomers. There are three forms of chitin: , , and chitin. The -form, is mainly obtained from crab and shrimp. Both and chitin/chitosan are commercially available [5]. Sources of chitinIn the book "Chitin" published by Muzarelli in 1977, we can find a complete list of organisms that contain chitin: Fungi, Algae, Cnidaria (jellyfish), Aschelminthes (round worm), Entoprocta, Bryozoa (Moss or lace animals, Phoronida (Horseshoe worms), Brachiopoda(Lamp shells), Echiruda, Annelida (Segmented worms), Mollusca, Arthropoda and Ponogophora [6]). Herring, P.J in 1979 wrote that chitin is the main component of arthropod exoskeletons, tendons, and the linings of their respiratory, excretory, and digestive systems, as well as insects external structure and some fungi. It is also found in the reflective material (iridophores) of both epidermis and eyes of arthropods and cephalopods (phylum: Mollusca) and the epidermal cuticle of the vertebrate Paralipophrys trigloides (fish) is also chitinous [7,8]. The main commercial sources of chitin are the shell wastes of shrimp, lobsters, crabs and krill. There are three forms of chitin: , , and chitin. The -form, is composed of alternating antiparallel polysaccharide strands and is mainly obtained from crab and shrimp. -Chitin is by far the most abundant; it occurs in fungal and yeast cell walls, krill, lobster and crab tendons and shells, shrimp shells, and insect cuticle. The rarer -chitin is composed of parallel strands of polysaccharides, is found in association with proteins in squid pens [9,10] and in the tubes synthesized by pogonophoran and vestimetiferan worms [11,12]. It also occurs in aphrodite chaetae [13] as well as in the lorica, built by some seaweeds or protozoa [14,15,16]. And 2 parallel chains alternating with an antiparallel strand constitute gamma chitin and are found in fungi [15].

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Section: Safe Biomaterialsmentioning

confidence: 96%

Is Chitosan a New Panacea? Areas of Application

Castro¹,

Paulín²

2012

The Complex World of Polysaccharides

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“…[11][12][13] It has also been reported that chitosan having a low degree of deacetylation (DA), which are active as absorption enhancer at both low and high molecular weights, shows a clear dose-dependent toxicity. 14) However, chitosan having a higher DA is active enhancer at high molecular weight, but show low toxicity at low molecular weight. As far as toxicity is concerned, it depends on the structural features of the chitosan polymer and not always related to its absorption enhancing effect.…”

Section: Propertiesmentioning

confidence: 99%

“…106,107) Chitosan solutions have shown to increase trans and para-cellular permeability in a reversible, dose-dependent manner depending on the molecular weight and degree of deacetylation of the chitosan. 108) The mechanism of action, which have been reported to be mediated by the positive charges on the chitosan, includes interactions with the tight junction proteins occludin and ZO-1, redistribution of F-actin, and slight destabilization of the plasma membrane. 107,109,110) This ability of chitosan to enhance permeation is also influenced by the pH of the environment.…”

Section: In Ocular Drug Deliverymentioning

confidence: 99%

Chitosan Nanoparticles: A Promising System in Novel Drug Delivery

2010

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The ability of nanoparticles to manipulate the molecules and their structures has revolutionized the conventional drug delivery system. The chitosan nanoparticles, because of their biodegradability, biocompatibility, better stability, low toxicity, simple and mild preparation methods, offer a valuable tool to novel drug delivery systems in the present scenario. Besides ionotropic gelation method, other methods such as microemulsion method, emulsification solvent diffusion method, polyelectrolyte complex method, emulsification cross-linking method, complex coacervation method and solvent evaporation method are also in use. The chitosan nanoparticles have also been reported to have key applications in parentral drug delivery, per-oral administration of drugs, in nonviral gene delivery, in vaccine delivery, in ocular drug delivery, in electrodeposition, in brain targeting drug delivery, in stability improvement, in mucosal drug delivery in controlled drug delivery of drugs, in tissue engineering and in the effective delivery of insulin. The present review describes origin and properties of chitosan and its nanoparticles along with the different methods of its preparation and the various areas of novel drug delivery where it has got its application.

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“…It implies the NH 2 group or positive NH 2 group would be necessary for the inhibitory effect of glucosamine in vitro. A possible ionic interactions between the positively-charged NH 2 group in GlcNH 2 ⋅HCl and negatively-charged sialic acid residue on tumor cell surface would possibly result in a change in the ionic environment of the cell membrane, which is important in maintaining cell integrity and cell growth (Olsen et al, 1989;Santini et al, 1997;Schipper et al, 1996). Thus, it is the lack of the amino group in NAG (Chandy and Sharma, 1990).…”

Section: Discussionmentioning

confidence: 99%

Antitumor activities of D-glucosamine and its derivatives

Zhang

Liu

Han

et al. 2006

J. Zhejiang Univ. - Sci. B

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Abstract:The growth inhibitory effects of D-glucosamine hydrochloride (GlcNH 2 ⋅HCl), D-glucosamine (GlcNH 2 ) and N-acetyl glucosamine (NAG) on human hepatoma SMMC-7721 cells in vitro were investigated. The results showed that GlcNH 2 ⋅HCl and GlcNH 2 resulted in a concentration-dependent reduction in hepatoma cell growth as measured by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. This effect was accompanied by a marked increase in the proportion of S cells as analyzed by flow cytometry. In addition, human hepatoma SMMC-7721 cells treated with GlcNH 2 ⋅HCl resulted in the induction of apoptosis as assayed qualitatively by agarose gel electrophoresis. NAG could not inhibit the proliferation of SMMC-7721 cells. GlcNH 2 ⋅HCl exhibited antitumor activity against Sarcoma 180 in Kunming mice at dosage of 125~500 mg/kg, dose of 250 mg/kg being the best. GlcNH 2 ⋅HCl at dose of 250 mg/kg could enhance significantly the thymus index, and spleen index and could promote T lymphocyte proliferation induced by ConA. The antitumor effect of GlcNH 2 ⋅HCl is probably host-mediated and cytocidal.

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Abstract: The structural features of chitosans determining absorption enhancement are not correlated with those determining toxicity, which makes it possible to select chitosans with maximal effect on absorption and minimal toxicity.

Cited by 346 publications

References 16 publications

Is Chitosan a New Panacea? Areas of Application

Is Chitosan a New Panacea? Areas of Application

Chitosan Nanoparticles: A Promising System in Novel Drug Delivery

Antitumor activities of D-glucosamine and its derivatives

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