Chemical induction of gut β-like-cells by combined FoxO1/Notch inhibition as a glucose-lowering treatment for diabetes

Abstract

Lifelong insulin replacement remains the mainstay of type 1 diabetes treatment. Genetic FoxO1 ablation promotes enteroendocrine cell (EECs) conversion into glucose-responsive β-like cells. Here, we tested whether chemical FoxO1 inhibitors can generate β-like gut cells. Pan-intestinal epithelial FoxO1 ablation expanded the EEC pool, induced β-like cells, and improved glucose tolerance in Ins2Akita/+ mice. This genetic effect was phenocopied by small molecule FoxO1 inhibitor, Cpd10. Cpd10 induced β-like cells that released insulin in response to glucose in mouse gut organoids, and this effect was strengthened by the Notch inhibitor, DBZ. In Ins2Akita/+ mice, a five-day course of either Cpd10 or DBZ induced insulin-immunoreactive β-like cells in the gut, lowered glycemia, and increased plasma insulin levels without apparent adverse effects. These results provide proof of principle of gut cell conversion into β-like cells by a small molecule FoxO1 inhibitor, paving the way for clinical applications.

Triple Notch/Tgfβ/FoxO1 blockade converts multiple intestinal sub-lineages into β-like cells and lowers glycemia in diabetic animals

“…In addition, expanding on Egozi (Egozi et al , 2021), we show that in human fetal intestine of 15- to 17-week gestational age, insulin-immunoreactive cells also colocalize with goblet/Paneth lineage markers but exclude active FOXO1, lending further support to the notion that FOXO1-inactive cells can be converted to β-like cells. These findings address the question of which type of cell can be converted into insulin-immunoreactive β-like cells, extending previous observations (Bouchi et al , 2014; Kitamoto et al, 2021; Talchai et al , 2012a).…”

“…Transforming Growth Factor-β (TGF-β), Wnt, fibroblast growth factor (FGF), Notch, bone morphogenic protein (BMP), and FoxO1, along with relevant receptors and signaling pathways, are involved in pancreatic and intestinal tissue patterning (Boonekamp et al, 2020; Nostro et al, 2011). FoxO1 and Notch signaling interact in determining intestinal stem cell differentiation into Paneth/goblet (Ludikhuize et al, 2020) and EEC lineages (Kitamoto et al , 2021; Zeve et al, 2022). Thus, we combined genetic FoxO1 knockout with pharmacological Notch inhibition (DBZ) to show that dual Notch/FoxO1 inhibition expands the Neurog3+ progenitor pool and its secretory lineage cell descendants.…”

Single-agent Foxo1 inhibition normalizes glycemia and induces gut β-like cells in streptozotocin-diabetic mice

“…In conclusion we have identified potent, selective, orally bioavailable Foxo1 inhibitors that show efficacy in normalizing glucose levels in STZ diabetes, either in combination with a Notch inhibitor (thereby extending our previous findings in the Akita model) (10) or as single agents, phenocopying the effect of genetic Foxo1 ablation in mouse (8). Our results suggest the use of Foxo1 inhibitors as a potential new class of agents for the treatment of insulin-dependent diabetes.…”

“…We further investigated whether it is possible to achieve a synergistic glucose lowering effect by combining Notch inhibition with the orally bioavailable clinical gamma secretase inhibitor PF-03084014 (PF) and FBT432 in the STZ model. The effects of treatment with PF alone are described in the previous report (10). Oral administration of PF at 150 mg/kg and FBT432 at 50 mg/kg b.i.d.…”

“…More recently, we have demonstrated that this new therapeutic paradigm can be realized by oral treatment with a small-molecule tool compound Foxo1 inhibitor (FBT10), when used in combination with a Notch inhibitor to increase the pool of EECs available for conversion to insulin-producing cells. We observed a significant improvement in glucose levels and glucose tolerance in Akita mice, a model of insulin-deficient diabetes (10).…”