Gonzalez-Hernandez, G. | bioRxiv Science

bioRxiv2026

Molecular signaling associated with antidepressant actions exhibits diurnal fluctuations in the prefrontal cortex and hippocampus of adult male and female mice

An increasing number of epidemiological and experimental studies have demonstrated a bidirectional relationship between mood disorders and the circadian system, with disrupted circadian rhythms contributing to depressive states, and their restoration playing a key role in antidepressants effects. In this context, we sought to examine whether key molecular targets of antidepressants exhibit diurnal regulatory patterns. Naive adult male and female C57BL/6 mice were euthanized at 3-hour intervals beginning at Zeitgeber Time 0 (ZT0), and hippocampal (HC) and medial prefrontal cortex (mPFC) tissues were collected for RT-qPCR and western blot analyses. We observed statistically significant diurnal rhythmicity in all analyzed transcripts (cFos, Arc, Nr4a1, Dusp1, Dusp5, and Dusp6) in both HC and mPFC samples, with peak expression occurring during the dark (active) phase (ZT15-18). Phosphorylation levels of TrkBY816 (tropomyosin-related kinase) and GSK3{beta}S9 (glycogen synthase kinase 3{beta}) also showed periodic rhythmicity, peaking during the light (inactive) phase. Levels of p-ERK2T185/Y187 (extracellular-signal regulated kinase) did not display rhythmicity, but peaked during the light phase in the HC, especially in males. Collectively, these findings demonstrate that antidepressant targets are subject to diurnal regulation, highlighting the importance of integrating circadian biology and time-of-day as relevant variables in the development of translationally relevant antidepressant research. HighlightsO_LIKey molecular targets of antidepressants exhibit diurnal regulation in adult mice C_LIO_LIDiurnal patterns were conserved across targets, sexes, and brain regions (HC&PFC) C_LIO_LIcFos, Arc, Nr4a1, Dusp1,5,6 mRNAs display peak expression during the dark phase C_LIO_LITrkBY816 and GSK3{beta}S9 phosphorylation peak during the light (inactive) phase C_LIO_LIAntidepressant mechanisms may be linked with circadian and sleep-wake dynamics C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=102 SRC="FIGDIR/small/716906v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@1e65e60org.highwire.dtl.DTLVardef@13e302corg.highwire.dtl.DTLVardef@1ccc25forg.highwire.dtl.DTLVardef@1ed10d3_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

bioRxiv2019

Effective buprenorphine use and tapering strategies: Endorsements and insights by people in recovery from opioid use disorder on a Reddit forum

Opioid use disorder (OUD) is a public health emergency in the United States. Over 47,000 overdose-related deaths in 2017 involved opioids. Medication-assisted treatment (MAT), in particular, buprenorphine and buprenorphine combination products such as Suboxone(R), is the most effective, evidence-based treatment for OUD. However, there are a limited number of conclusive scientific studies that provide guidance to medical professionals about strategies for using buprenorphine to achieve stable recovery. In this study, we used data-driven natural language processing methods to mine a total of 16,146 posts about buprenorphine from 1933 unique users on the anonymous social network Reddit. Analysis of a sample of these posts showed that 74% of the posts described users personal experiences and that the top three topics included advice on using Suboxone(R) (55.0%), Suboxone(R) dosage information (35.5%) and information about Suboxone(R) tapering (32.0%). Based on two models, one that incorporated upvoting by other members and one that did not, we found that Reddit users reported more successful recovery with longer tapering schedules, particularly from 2.0 mg to 0.0 mg (median: 93 days; mean: 95 days), as compared to shorter tapering schedules investigated in past clinical trials. Diarrhea, insomnia, restlessness, and fatigue were commonly reported adverse events. Physical exercise, clonidine, and Imodium(R) were frequently reported to help during the recovery process. Due to the difficulties of conducting longer-term clinical trials involving patients with OUD, clinicians should consider other information sources including peer discussions from the abundant, real-time information available on Reddit. Significance StatementOpioid use disorder (OUD) is a national crisis in the United States and buprenorphine is one of the most effective evidence-based treatments. However, few studies have explored successful strategies for using and tapering buprenorphine to achieve stable recovery, particularly due to the difficulties of conducting long-term studies involving patients with OUD. In this study, we show that discussions on the anonymous social network Reddit may be leveraged, via automatic text mining methods, to discover successful buprenorphine use and tapering strategies. We discovered that longer tapering schedules, compared to those investigated in past clinical trials, may lead to (self-reported) sustained recovery. Furthermore, Reddit posts also provide key information regarding buprenorphine withdrawal, cravings, adjunct medications for withdrawal symptoms and relapse prevention strategies.

pharmacology and toxicology↗