Neoponcirin causes anxiolytic-like effects in mice when administered intraperitoneally but not orally. Neoponcirin is non-water-soluble and insoluble in solvents, and in medium acid, it isomerizes, reducing its bioavailability. To improve the pharmacological properties of neoponcirin, we formed a neoponcirin complex with beta-cyclodextrin (NEO/βCD), which was characterized by FT-IR, UV-Vis, and NMR, and their solubility profile. We evaluated the antidepressant-like effects of NEO/βCD acutely administered to mice orally in the behavioral paradigms, the tail suspension (TST) and the forced swimming (FST) tests. We also analyzed the benefits of repeated oral doses of NEO/βCD on depression- and anxiety-like behaviors induced in mice by chronic unpredictable mild stress (CUMS), using the FST, hole board, and open field tests. We determined the stressed mice’s expression of stress-related inflammatory cytokines (IL-1β, IL-6, and TNFα) and corticosterone. Results showed that a single or chronic oral administration of NEO/βCD caused a robust antidepressant-like effect without affecting the ambulatory activity. In mice under CUMS, NEO/βCD also produced anxiolytic-like effects and avoided increased corticosterone and IL-1β levels. The effects of the NEO/βCD complex were robust in both the acute and the stress chronic models, improving brain neurochemistry and recovering immune responses previously affected by prolonged stress.

Smell dysfunction affects quality of life and is considered an early clinical sign of Alzheimer’s and Parkinson’s diseases. Olfactory loss increases with age and is associated with certain ciliopathies, a group of genetic disorders characterized by a wide spectrum of multisystemic disturbances. The dysfunction of mature olfactory sensory neurons (OSNs) in the olfactory neuronal pathway remains poorly understood. Previous evidence suggests that primary cilia proteins are involved in the maturation of olfactory sensory neurons (OSNs). In this study, we obtained olfactory neuronal precursors (ONPs) from the olfactory mucosa of young and older healthy volunteers who reported smell impairment (hyposmia) without neurological deficits or underlying airflow issues (conductive olfactory loss), and from normosmic individuals. In vitro analysis of ONPs showed that these cells can form primary cilia in normosmic individuals, while in hyposmic participants, there is a reduction in cilia frequency and a shorter length. In addition, ONPs from hyposmic individuals had a decrease in proliferation and cell differentiation. Our data indicates that alterations in molecular pathways related to primary cilia formation and the proliferation of ONPs lead to defects in neuronal maturation. These changes may hinder the differentiation of olfactory sensory neurons OSNs and contribute, at least in part, to olfactory loss.

Smell dysfunction affects quality of life and is considered an early clinical sign of Alzheimer’s and Parkinson’s diseases. Olfactory loss increases with age and is associated with certain ciliopathies, a group of genetic disorders characterized by a wide spectrum of multisystemic disturbances. The dysfunction of mature olfactory sensory neurons (OSNs) in the olfactory neuronal pathway remains poorly understood. Previous evidence suggests that primary cilia proteins are involved in the maturation of olfactory sensory neurons (OSNs). In this study, we obtained olfactory neuronal precursors (ONPs) from the olfactory mucosa of young and older healthy volunteers who reported smell impairment (hyposmia) without neurological deficits or underlying airflow issues (conductive olfactory loss) and from normosmic individuals. In vitro analysis of ONPs showed that these cells can form primary cilia in normosmic individuals, while in hyposmic participants, there is a reduction in cilia frequency and a shorter length. In addition, ONPs from hyposmic individuals had a decrease in proliferation and cell differentiation. Our data indicate that alterations in molecular pathways related to primary cilia formation and the proliferation of ONPs lead to defects in neuronal maturation. These changes may hinder the differentiation of olfactory sensory neurons OSNs and contribute, at least in part, to olfactory loss.