TNF and asthma: In addition, several studies have demonstrated that betaine inhibits the transcriptional activation of nuclear factor‐κB (NF‐κB) and production of tumor necrosis factor‐ɑ (TNF‐ɑ) and IL‐1β,42, 43, 44 which are considered to be important chemokines for neutrophils and strongly associated with poor control of severe asthma.45, 46