Background:
Birch hemicellulose, mainly composed of glucuronoxylan (GX), is emerging as a sustainable food hydrocolloid. However, studies on health impacts of GX are limited.
Aim(s):
To study the effects of birch-derived GX on the expression of tight junction proteins in the colonic mucosa of healthy rats.
Methods:
An animal intervention study was conducted on 42 rats, stratified into three groups that received different diets for 28 days: 1) AIN-93 + 10% of cellulose (control), 2) AIN-93 + 10% of highly purified GX (GXpure), and 3) AIN-93 + 10% polyphenol-and-GX-rich extract (GXpoly). Protein expressions in the proximal and distal colon were analysed with western blot and examined with ANOVA and Tukey’s post-hoc tests.
Results:
In the proximal colon, no statistically significant differences in occludin, claudin-1 and claudin-7 expression were observed between the control and GX-diet groups. Similarly, no statistically significant differences in all tight junction proteins expressions were observed between the three groups. There were no differences in the results when adjusted for sex.
Conclusion:
The findings suggest that birch-derived GX consumption did not significantly alter the expression of TJ proteins, which is a positive sign for its usage as food hydrocolloids. As this is one of the first studies on this topic, further research, especially on a diseased model, is needed before determining the safety of birch-derived GX for human consumption