Vortioxetine treatment for major depressive disorder with the co-morbidity of irritable bowel syndrome with diarrhoea: a case report

CSTI-300 (SMP-100); a Novel 5-HT3 Receptor Partial Agonist with Potential to Treat Patients with Irritable Bowel Syndrome or Carcinoid Syndrome

The 5-hydroxytryptamine (5-HT) (serotonin) 5-HT₃ receptor represents a clinical target for antagonists to deliver symptomatic relief to patients with diarrhea-predominant irritable bowel syndrome (IBS-d) or carcinoid syndrome. Unfortunately, this pharmacological strategy can present side effects (e.g., severe constipation). The present study investigates the potential of a novel 5-HT₃ receptor partial agonist, CSTI-300, to treat patients with IBS-d and other conditions associated with discomfort from colonic distension, with a predicted reduced side-effect profile. The in vitro and in vivo preclinical pharmacology of the drug CSTI-300 was investigated to explore the potential to treat patients with IBS-d. CSTI-300 displayed selective high affinity for the human and rat 5-HT₃ receptor (K_i approximately 2.0 nM) and acted as a partial agonist (approximately 30%-50% intrinsic efficacy) in vitro. In an in vivo model of IBS-d, the rat colon distension model, CSTI-300 displayed dose-dependent efficacy. In addition, oral administration of CSTI-300 to dogs that achieved plasma levels of the drug exceeding the K_i value for the 5-HT₃ receptor failed to either evoke emesis or alter the state of feces. Pharmacokinetics for CSTI-300 in rat and dog identified high levels of oral availability with t _1/2 range of 1.6-4.4 hours. The preclinical pharmacology of the lead candidate drug, CSTI-300, supports the potential of this novel drug to offer symptomatic relief to patients with irritable bowel syndrome and carcinoid syndrome with a rationale for a reduced "on-target" side-effect profile relative to 5-HT₃ receptor antagonists, such as alosetron. SIGNIFICANCE STATEMENT: There is a lack of effective current treatment for diarrhea-predominant irritable bowel syndrome and carcinoid syndrome, and in both conditions, overactivity of the 5-hydroxytryptamine (5-HT) 5-HT₃ receptor is thought to be implicated in the pathophysiology. Because 5-HT₃ receptor blockade with antagonists results in significant side effects, we present evidence that treatment with a suitable 5-HT₃ receptor partial agonist will alleviate some symptoms associated with these conditions yet, without fully inhibiting the receptor, predict a less pronounced side-effect profile associated with this therapeutic strategy.

Exploring the multicomponent synergy mechanism of Banxia Xiexin Decoction on irritable bowel syndrome by a systems pharmacology strategy

ETHNOPHARMACOLOGICAL RELEVANCE

Banxia Xiexin Decoction (BXD) is a representative prescription to regulate spleen and stomach in "Treatise on Febrile Diseases", which has been proven effective for the clinical treatment of irritable bowel syndrome (IBS) in the past decades. However, the active principles and molecular mechanisms involved in BXD against IBS are vague yet.

AIM OF THE STUDY

To unfold multicomponent synergy mechanism of BXD on irritable bowel syndrome, this work explored active principles, drug targets and crucial pathways using a systems pharmacology strategy.

MATERIALS AND METHODS

In this study, a systems pharmacology based strategy was applied by the procedures integrating compound database construction, ADME evaluation, target identification, functional annotation, pathway enrichment analysis, network analysis, and molecular docking verification. The 158 compounds from BXD were selected for the screening. The Compound-Target network (C-T) and the Target-Pathway network (T-P) were constructed. The bioinformatics and network topology were employed to systematically reveal multicomponent-target interactions of BXD. The affinity between important ingredients and the kernel targets was validated using molecular mechanics simulation.

RESULTS

The 35 potential important ingredients and the 16 associated kernel targets were identified. 27 crucial pathways, in which the kernel targets participated, could regulate the biological processes, such as synthesis of inflammatory mediators, smooth muscle relaxation and synaptic plasticity, closely related to pathological mechanism of IBS. The cross-talk interactions were revealed between TNF signaling pathway, Dopaminergic synapse and cGMP-PKG signaling pathway, which would exert the synergistic influences on the occurrence and treatment of the IBS. PTGS2, CALM, NOS2, SCN5A, and PRSS1 might become novel drug targets for IBS.

CONCLUSIONS

The study demonstrated that the synergy molecular mechanisms of BXD mainly involved three therapeutic modules including inhibiting inflammatory reaction, maintaining intestinal function and improving psychological regulation via the multicomponent-target interaction networks. It may also provide the promising drug targets and therapeutic agents for the development of new medicines.