NOX4 and constipation disorder: Among them, some genes such as T cell differentiation protein (MAL), cadherin 16 (CDH16), tight junction-associated protein 1 (TJAP1), and NADPH oxidase 4 (NOX4) were upregulated in the IBS-constipation (IBS-C) group, while other genes such as damage-specific DNA-binding protein 1 (DDB1) and CUL4-associated factor 1 (DCAF1), aldehyde dehydrogenase 9, family member A1 (ALDH9A1), synaptosome-associated protein 47 (SNAP47), palladin, cytoskeletal-associated protein (PALLD) and NK3 homeobox 1 (NKX3-1) were downregulated in the same group [12].