STW 5, a herbal medicinal product, has been shown to stimulate intestinal chloride
secretion. Whether it can modulate paracellular and transcellular permeability remains
currently unknown. Therefore, we did study the ability of STW 5 to modulate intestinal
permeability under basal and repeated acute stress conditions.
C57 bl6 mice were gavaged for 14 days with STW 5 (3 mL/kg). After 10 days of treatment,
mice were subjected to water avoidance stress (WAS) during 4 consecutive days. In vivo permeability to FITC -Sulfonic Acid (FSA, 400 Da) and Horse Radish Peroxydase (HRP,
44KDa), total transit time and colonic transit (fecal pellet output – FPO) were assessed
at Day 0 (D0), D10 and D14 of IB treatment. Ex vivo permeability to FSA and HRP was assessed on jejunum, ileum, proximal colon and distal
colon at D14 using Ussing chambers. Corticosterone blood level was measured at D11
and D14.
While in vivo permeability to FSA and HRP as well as total transit time were not modified by STW
5 in basal and WAS conditions, STW 5 prevented the increase in permeability to FSA
induced by WAS in the distal colon ex vivo. STW 5 prevented the increase in permeability to HRP induced by WAS in the jejunum
and proximal colon. While STW 5 tended to increase colonic transit as compared to
control in basal conditions, it did not influence the increase in colonic transit
induced by WAS. STW 5 did not modify the changes in corticosterone induced by WAS.
STW 5 (Iberogast) obviously can prevent WAS induced changes in paracellular and transcellular
permeability in specific regions of the gastrointestinal tract. Such effects could
contribute to the therapeutic effects of STW 5 in irritable bowel syndrome and support
its use in indications in which barrier functions are altered.
