J Nutritional Biochemistry in press.pdf (219.07 kB)
Download fileMolecular Signature of Kappa-Carrageenan Mimics Chondroitin-4-Sulfate and Dermatan Sulfate and Enables Interaction with Arylsulfatase B
journal contribution
posted on 2013-11-22, 00:00 authored by Sumit Bhattacharyya, Joanne K. TobacmanThe common food additive kappa-carrageenan ( -CGN) is a sulfated
polysaccharide that resembles chondroitin-4-sulfate (C4S) and dermatan sulfate (DS). All
have a sulfate group on C4 of a glycoside (galactose for carrageenan and Nacetylgalactosamine
for C4S), and the sulfate-bearing glycoside is linked in a -1,4-
configuration to an unsulfated, 6-carbon sugar (galactose for carrageenan, glucuronate for
C4S, and iduronate for DS). The enzyme arylsulfatase B (ARSB; N-acetylgalactosamine-
4-sulfate) is the highly selective enzyme that removes the 4-sulfate group from the nonreducing
terminus of C4S and DS, thereby regulating subsequent degradation. In this
report, -CGN is shown to be a substrate for recombinant human ARSB (rhARSB).
Sulfate was generated from both C4S and -CGN following incubation with rhARSB.
Exposure of human colonic epithelial cells to -CGN, but not to C4S produced reactive
oxygen species (ROS) and increased Interleukin (IL)-8 secretion. The ROS production
from -CGN was reduced by exposure to rhARSB, but increased by competition from
C4S or DS, but not from chondroitin-6-sulfate (C6S). Prior treatment of either lambda- or
iota-CGN with rhARSB had no impact on ROS, IL-8, or inorganic sulfate production,
demonstrating a specific effect of the molecular configuration of -CGN. By mimicry of
C4S and DS and by interaction with ARSB, -CGN can directly interfere with the
normal, cellular functions of C4S, DS, and ARSB. Since C4S and DS are present in high
concentration in tissues, the impact of -CGN exposure may be due to some extent by
interference with the normal biological functions of ARSB, C4S, and DS.