Obesity-induced taste bud loss in mice is only partially remediated long after return to a healthy weight.

Abstract

BACKGROUND: Mice developing obesity through their diet have fewer taste buds than littermates maintained on healthy chow. In this experiment we investigated if diet-induced taste bud loss, inflammation, and an attenuated regenerative capacity of taste buds would persist after return to a healthy weight. METHODS: 8-week-old C57Bl/6 mice were split into three groups, one (chow) maintained on a standard lab chow diet for 16 weeks, a second (HFD) maintained on a high fat diet for 16 weeks, while the third (diet) was placed on a HFD for the first 8 weeks, then switched to the healthy diet. RESULTS: In this second 8 week period, diet mice lost all excess weight. Despite returning to a healthy weight, dieted mice showed only minor recovery of taste buds, with better recovery for proliferating cells and cells undergoing apoptosis. HFD mice exhibited increased tumor necrosis factor alpha (TNFα) expression, with altered Sonic Hedgehog (Shh) and Bone morphogenetic protein 4 (BMP4) expression, both linked to taste homeostasis. CONCLUSIONS: Overall, data demonstrate that obesity has a persistent effect on taste buds long after excess weight is lost.