2-BFI Provides Neuroprotection Against Fluorosis by Stabilizing Endoplasmic Reticulum–Mitochondria Contact Sites and Inhibiting Activation of the NLRP3 Inflammasome

2-(2-benzofu-ranyl)-2-imidazoline (2-BFI) is a drug that has attracted much attention in recent years. It has a therapeutic effect on brain diseases in animal models such as Alzheimer’s disease and cerebral infarction. However, whether 2-BFI affords neuroprotection against the toxicity of fluoride, which can cross the blood–brain barrier and cause neurological dysfunction is not known. We investigated the cell viability and apoptosis of SH-SY5Y cells and primary cultures of cortical neurons exposed to fluoride, and 2-BFI was used to protect both two kinds of cells against the effects of fluoride. We found that 2-BFI can provide neuroprotection on SH-SY5Y cells and primary cultures of cortical neurons upon fluorosis by maintaining the stability of endoplasmic reticulum–mitochondria contact sites and inhibiting activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome. This study may provide a new method for protecting against the neurotoxicity induced by fluoride exposure.