Estradiol- and Progesterone-Associated Changes in microRNA-Induced Silencing and Reduced Antiseizure Efficacy of an Antagomir in Female Mice.

About one-third of individuals living with epilepsy have treatment-resistant seizures. Alternative therapeutic strategies are thus urgently needed. One potential novel treatment target is miRNA-induced silencing, which is differentially regulated in epilepsy. Inhibitors (antagomirs) of specific microRNAs (miRNAs) have shown therapeutic promise in preclinical epilepsy studies; however, these studies were mainly conducted in male rodent models, and research into miRNA regulation in females and by female hormones in epilepsy is scarce. This is problematic because female sex and the menstrual cycle can affect the disease course of epilepsy and may, therefore, also alter the efficacy of potential miRNA-targeted treatments. Here, we used the proconvulsant miRNA miR-324-5p and its target, the potassium channel Kv4.2, as an example to test how miRNA-induced silencing and the efficacy of antagomirs in epilepsy are altered in female mice. We showed that Kv4.2 protein is reduced after seizures in female mice similar to male mice; however, in contrast to male mice, miRNA-induced silencing of Kv4.2 is unchanged, and miR-324-5p activity, as measured by the association with the RNA-induced silencing complex, is reduced in females after seizure. Moreover, an miR-324-5p antagomir does not consistently reduce seizure frequency or increase Kv4.2 in female mice. As a possible underlying mechanism, we found that miR-324-5p activity and the silencing of Kv4.2 in the brain were differentially correlated with plasma levels of 17ß-estradiol and progesterone. Our results suggest that hormonal fluctuations in sexually mature female mice influence miRNA-induced silencing and could alter the efficacy of potential future miRNA-based treatments for epilepsy in females.

MiR-324-5p inhibition after intrahippocampal kainic acid-induced status epilepticus does not prevent epileptogenesis in mice.

Background: Acquired epilepsies are caused by an initial brain insult that is followed by epileptogenesis and finally the development of spontaneous recurrent seizures. The mechanisms underlying epileptogenesis are not fully understood. MicroRNAs regulate mRNA translation and stability and are frequently implicated in epilepsy. For example, antagonism of a specific microRNA, miR-324-5p, before brain insult and in a model of chronic epilepsy decreases seizure susceptibility and frequency, respectively. Here, we tested whether antagonism of miR-324-5p during epileptogenesis inhibits the development of epilepsy. Methods: We used the intrahippocampal kainic acid (IHpKa) model to initiate epileptogenesis in male wild type C57BL/6 J mice aged 6-8 weeks. Twenty-four hours after IHpKa, we administered a miR-324-5p or scrambled control antagomir intracerebroventricularly and implanted cortical surface electrodes for EEG monitoring. EEG data was collected for 28 days and analyzed for seizure frequency and duration, interictal spike activity, and EEG power. Brains were collected for histological analysis. Results: Histological analysis of brain tissue showed that IHpKa caused characteristic hippocampal damage in most mice regardless of treatment. Antagomir treatment did not affect latency to, frequency, or duration of spontaneous recurrent seizures or interictal spike activity but did alter the temporal development of frequency band-specific EEG power. Conclusion: These results suggest that miR-324-5p inhibition during epileptogenesis induced by status epilepticus does not convey anti-epileptogenic effects despite having subtle effects on EEG frequency bands. Our results highlight the importance of timing of intervention across epilepsy development and suggest that miR-324-5p may act primarily as a proconvulsant rather than a pro-epileptogenic regulator.

Transcriptional profile of spinal dynorphin-lineage interneurons in the developing mouse.

Mounting evidence suggests that the spinal dorsal horn (SDH) contains multiple subpopulations of inhibitory interneurons that play distinct roles in somatosensory processing, as exemplified by the importance of spinal dynorphin-expressing neurons for the suppression of mechanical pain and chemical itch. Although it is clear that GABAergic transmission in the SDH undergoes significant alterations during early postnatal development, little is known about the maturation of discrete inhibitory "microcircuits" within the region. As a result, the goal of this study was to elucidate the gene expression profile of spinal dynorphin (pDyn)-lineage neurons throughout life. We isolated nuclear RNA specifically from pDyn-lineage SDH interneurons at postnatal days 7, 21, and 80 using the Isolation of Nuclei Tagged in Specific Cell Types (INTACT) technique, followed by RNA-seq analysis. Over 650 genes were ≥2-fold enriched in adult pDyn nuclei compared with non-pDyn spinal cord nuclei, including targets with known relevance to pain such as galanin (Gal), prepronociceptin (Pnoc), and nitric oxide synthase 1 (Nos1). In addition, the gene encoding a membrane-bound guanylate cyclase, Gucy2d, was identified as a novel and highly selective marker of the pDyn population within the SDH. Differential gene expression analysis comparing pDyn nuclei across the 3 ages revealed sets of genes that were significantly upregulated (such as Cartpt, encoding cocaine- and amphetamine-regulated transcript peptide) or downregulated (including Npbwr1, encoding the receptor for neuropeptides B/W) during postnatal development. Collectively, these results provide new insight into the potential molecular mechanisms underlying the known age-dependent changes in spinal nociceptive processing and pain sensitivity.

Evaluating the effect of a campus-wide social norms marketing intervention on alcohol-use perceptions, consumption, and blackouts.

OBJECTIVE: To evaluate the effect of a campus-wide social norms marketing intervention on alcohol-use perceptions, consumption, and blackouts at a large, urban, public university. PARTICIPANTS: 4,172 college students (1,208 freshmen, 1,159 sophomores, 953 juniors, and 852 seniors) who completed surveys in Spring 2015 for the Spit for Science Study, a longitudinal study of students' substance use and emotional health. METHODS: Participants were e-mailed an online survey that queried campaign readership, perception of peer alcohol use, alcohol consumption, frequency of consumption, and frequency of blackouts. Associations between variables were evaluated using path analysis. RESULTS: We found that campaign readership was associated with more accurate perceptions of peer alcohol use, which, in turn, was associated with self-reported lower number of drinks per sitting and experiencing fewer blackouts. CONCLUSIONS: This evaluation supports the use of social norms marketing as a population-level intervention to correct alcohol-use misperceptions and reduce blackouts.

Ethnic Comparisons in HIV Testing Attitudes, HIV Testing, and Predictors of HIV Testing Among Black and White College Students.

OBJECTIVES: This study's primary aim was to examine ethnic differences in predictors of HIV testing among Black and White college students. We also examined ethnic differences in sexual risk behaviors and attitudes toward the importance of HIV testing. PARTICIPANTS/METHOD: An analytic sample of 126 Black and 617 White undergraduatestudents aged 18-24 were analyzed for a subset of responses on the American College Health Association-National College Health Assessment II (ACHA-NCHA II) (2012) pertaining to HIV testing, attitudes about the importance of HIV testing, and sexual risk behaviors. Predictors of HIV testing behavior were analyzed using logistic regression. t tests and chi-square tests were performed to access differences in HIV test history, testing attitudes, and sexual risk behaviors. RESULTS: Black students had more positive attitudes toward testing and were more likely to have been tested for HIV compared to White students. A greater number of sexual partners and more positive HIV testing attitudes were significant predictors of HIV testing among White students, whereas relationship status predicted testing among Black students. Older age and history of ever having sex were significant predictors of HIV testing for both groups. There were no significant differences between groups in number of sexual partners or self-reports in history of sexual experience (oral, vaginal, or anal). CONCLUSIONS: Factors that influence HIV testing may differ across racial/ethnic groups. Findings support the need to consider racial/ethnic differences in predictors of HIV testing during the development and tailoring of HIV testing prevention initiatives targeting college students.

Do "clicker" educational sessions enhance the effectiveness of a social norms marketing campaign?

OBJECTIVE: social norms campaigns are a cost-effective way to reduce high-risk drinking on college campuses. This study compares effectiveness of a "standard" social norms media (SNM) campaign for those with and without exposure to additional educational sessions using audience response technology ("clickers"). METHODS: American College Health Association's National College Health Assessment questions are used to evaluate actual and perceived use. Additional survey questions assess individual exposure to the interventions. RESULTS: the authors find "clicker" technology to be more effective than social norms poster media alone in reducing misperceptions of normative alcohol use for those students who attended clicker sessions. CONCLUSION: poster SNM campaigns may be most effective when supported by group "clicker" heath-related sessions.