Table 1.

Chemical and molecular factors in the multifactorial mechanisms implicated in mucosal functions in IBS

	Secretion/Absorption	Barrier	Inflammation	Sensation
Lumen	Bile acids; short-chain fatty acids	Bile acids	Bacterial proteases/toxins
Mucosa	Ion channel expression	Tight junction expression; microRNA expression		MicroRNA expression; neurotransmitters; mesotrypsin
Lamina propria		Serine proteases	Mast cells; serine proteases