Dietary polyphenols drive alterations in behavior, transcriptional regulation, and commensal microbiota in models of opioid use.

Opioid Use Disorder (OUD) is a neuropsychiatric condition associated with tremendous medical and social consequences. Despite this burden, current pharmacotherapies for OUD are ineffective or intolerable for many patients. As such, interventions aimed at promoting overall health and resilience against OUD are of immense clinical and societal interest. Recently, treatment with a Bioactive Dietary Polyphenol Preparation (BDPP) was shown to promote behavioral resilience and adaptive neuroplasticity in multiple models of neuropsychiatric disease. Here, we assessed effects of BDPP treatment on behavioral and molecular responses to repeated morphine treatment. We find that BDPP pre-treatment alters responses across the dose range for both locomotor sensitization and conditioned place preference. Most notably, polyphenol treatment consistently reduced formation of preference at low dose (5mg/kg) morphine but enhanced it at high dose (15mg/kg). In parallel, we performed transcriptomic profiling of the nucleus accumbens, which again showed a dose x polyphenol interaction. At high dose morphine, BDPP pre-treatment potentiated gene expression changes induced by morphine particularly for genes related to synaptic function. We also profiled microbiome composition and function, as polyphenols are metabolized by the microbiome and can act as prebiotics. The profile revealed polyphenol treatment markedly altered microbiome composition and function, particularly in the low dose morphine group. Finally, we investigated involvement of the SIRT1 histone deacetylase, and the role of specific polyphenol metabolites in these behavioral phenotypes. Taken together, these results demonstrate that polyphenols have robust dose-dependent effects on behavioral and physiological responses to morphine and lay the foundation for future translational work. ### Competing Interest Statement The authors have declared no competing interest.