Antitumor Effects of Various Low-Molecular-Weight Chitosans Are Due to Increased Natural Killer Activity of Intestinal Intraepithelial Lymphocytes in Sarcoma 180–Bearing Mice

Abstract

Various low-molecular-weight chitosans such as the 21-kDa, 46-kDa, and 120-kDa chitosans obtained by enzymatic hydrolysis of a high-molecular-weight chitosan (average molecular weight, 650 kDa) had low viscosity and were water soluble. We examined the antitumor activity of various water-soluble chitosans with different molecular weights in sarcoma 180-bearing mice. A 21-kDa water-soluble chitosan and oligochitosan (100 and 300 mg/kg body) administered by i.g. intubation reduced the tumor growth and final tumor weight in sarcoma 180-bearing mice. A 46-kDa water-soluble chitosan at a dose of 100 mg/kg body reduced the tumor growth and final tumor weight, but had no effect at 300 mg/kg. On the other hand, a 130-kDa water-soluble chitosan had no effect on tumor growth. The 21- and 46-kDa chitosans (10 mg/L) enhanced the natural killer (NK) activity in intestinal intraepithelial lymphocytes (IELs) or splenic lymphocytes. The NK activity of low-molecular-weight chitosan (21- and 46-kDa chitosans)-treated IELs or splenic lymphocytes was stronger than that of high-molecular-weight chitosan (130- and 650-kDa chitosans)-treated IELs or splenic lymphocytes. In addition, low-molecular-weight chitosan-treated IELs or splenic lymphocytes also enhanced the cytotoxic activity against sarcoma 180 cells. In an in vivo study, although low-molecular-weight chitosan-treated IELs had cytotoxic activity against tumor cells, splenic lymphocytes treated with chitosans had no effect. These findings suggest that the antitumor activity of low-molecular-weight chitosans (12- and 46-kDa chitosans) and oligochitosan might be due in part to the enhancement of NK activity in IELs. Thus, the low-molecular-weight chitosans or oligochitosan might be useful in preventing tumor growth through the activation of intestinal immune functions.

Chitosan multiple addition enhances laccase production from Trametes versicolor

“…Chitosan could have facilitated increased synthesis of intracellular laccase and its efflux, thereby increasing the laccase activity in the medium. Chitosan molecule is a multi-cationic polymer due to its exposed amino groups [1,[4][5][6]. It can bind charged cell surfaces, trigger the cavitations of the cell wall and facilitate the leak of laccase from the intracellular into the extracellular milieu [30].…”

“…This polysaccharide is nontoxic, semicrystalline, biocompatible and biodegradable [3]. Chitosan molecules contain many exposed positively charged ions and this accounts for its potentials in mediating lots of biological activities [1,[4][5][6]. These chemical characteristics make chitosan to be of great use/importance in food processing, agriculture, nanobiotechnology and medicine [3][4][5].…”

“…These chemical characteristics make chitosan to be of great use/importance in food processing, agriculture, nanobiotechnology and medicine [3][4][5]. It exhibits antibacterial, antitumor, antifungi and hypocholesterolemic activity [2][3][4][5][6]. In plants, it stimulates growth, induces disease defense responses, regulates immunity, reduces transpiration, extends shelf life and increases yield [2,4].…”

Perbedaan Pengaruh Pemberian Kitosan Berat Molekul Tinggi dan Rendah terhadap Jumlah Pembuluh Darah pada Proses Penyembuhan Luka Pencabutan Gigi

“…9 Kitosan yang memiliki berat molekul tinggi maka viskositasnya tinggi, sedangkan kitosan yang memiliki berat molekul rendah maka viskositasnya juga rendah, karena semakin tinggi berat molekul maka ukuran partikelnya juga semakin besar sehingga proses pelarutan semakin lambat. 10 Kitosan berat molekul tinggi memiliki sifat mukoadhesif yang baik dalam menutup luka. 11 Penelitian yang dilakukan Gunawan (2014) tentang pembuatan formulasi kitosan gel ditambah dengan NaOH untuk menetralkan pH sudah memenuhi kriteria pengaplikasian gel dalam rongga mulut, namun viskositasnya menjadi rendah sehingga sulit untuk diaplikasikan ke dalam rongga mulut.…”

Evaluation Antioxidant and cytotoxic activities of novel chitooligosaccharides prepared from chitosan via enzymatic hydrolysis and ultrafiltration

“…Chitooligosaccharides inhibited the growth of tumor cells through influence immuno-enhancing effects and also by inhibiting angiogenesis (Wu et al, 2012). In intestinal intraepithelial lymphocytes, chitooligosaccharides improved the natural killer activity and decreased tumor growth in mice (Maeda and Kimura, 2004). They caused death of human hepatocellular carcinoma cells by regulation of the pro-apoptotic protein (Xu et al, 2008).…”