Objective Herbal medicinal products (HMPs) are commonly used to treat symptoms of mild functional gastrointestinal disorders (FGID) such as functional dyspepsia (FD) and irritable bowel syndrome (IBS). Gasteo ® , an HMP containing a combination of 6 liquid plant extracts, has been on the market for over 60 years to treat FD, but little is known about its mode of action. This in vitro study aimed to investigate the effects of the HMP on pharmacological targets relevant for FD. Methods We investigated the anti-inflammatory properties of the HMP by measuring the release of the interleukins IL-1ß, IL-6, IL-8, the monocyte chemoattractant protein-1 (MCP-1), the tumor necrosis factor-α (TNF-α), and the prostaglandin E2 (PGE 2 ) release in a human monocyte cell model. We also assessed its effects on colonic epithelial barrier dysfunction by measuring the transepithelial electrical resistance (TEER) in Caco-2 cells, and carried out GPR55, TGR5 and TRPV1 functional assays, as well as muscarinic M3 and serotonin–type 3 (5-HT 3 ) receptor binding assays. Results The HMP inhibited the lipopolysaccharide-induced release of all investigated inflammatory mediators in human monocytes and prevented colonic epithelial barrier dysfunction in Caco-2 cells. The HMP had no effects on GPR55 or TGR5 functions, but it antagonized TRPV1. It also inhibited the binding of 3H-N-methylscopolamine to the M3 receptor and showed a weak inhibition of the binding of 3H-GR65630 to 5-HT 3 . Conclusion The HMP studied exhibited several in vitro pharmacological properties that could explain the effects observed on FD.
Günnewich et al. (Sun,) studied this question.