Sex Differences and Similarities in Hippocampal Cellular Proliferation and the Number of Immature Neurons during Adolescence in Rats.

Adolescence is associated with significant reductions in hippocampal cellular proliferation and neurogenesis, the physiological and behavioral implications of which are unclear. Though sex differences exist in these proliferative processes in adulthood, relatively little is known about the role sex plays in these adolescent-related changes. To address this gap, we examined cross-sectional area of the dentate gyrus and cellular proliferation, as measured by Ki-67 immunohistochemistry, in pre- (30 days), mid- (45 days), and post-adolescent (70 days) male and female rats. We also investigated the number of immature neurons using doublecortin (DCX) immunohistochemistry in pre- and post-adolescent males and females. Despite increases in the size of the dentate gyrus during adolescence, we found significant adolescent-related decreases in hippocampal proliferation in both males and females, with a more dramatic decrease in males, indicating both age- and sex-dependent changes in the dentate gyrus. We also found an adolescent-related decline in the number of immature neurons in the dentate gyrus of male rats and a female-biased sex difference in the number of immature neurons in adults. Given these significant changes in the dentate gyrus, these data suggest that this period in development might be particularly sensitive to internal and external factors known to modulate neurogenesis, with potential sex-specific neurobehavioral ramifications.

Neuropathogenesis of HIV and emerging therapeutic targets.

INTRODUCTION: HIV infection causes a wide range of neurological complications, many of which are among the most common complications of chronic HIV infection in the era of combined antiretroviral therapy. These neurological conditions arise due to complex interactions between HIV viral proteins and neuronal and glial cells that lead to the activation of various inflammatory and neurotoxic pathways across the nervous system. AREAS COVERED: This review summarizes the current literature on the pathogenesis and clinical manifestations of neurological injuries associated with HIV in the brain, spinal cord, and peripheral nervous system. Molecular pathways relevant for possible therapeutic targets or advancements are emphasized. Gaps in knowledge and current challenges in therapeutic design are also discussed. EXPERT OPINION: Several challenges exist in the development of therapeutic targets for HIV-associated cognitive impairments. However, recent developments in drug delivery systems and treatment strategies are encouraging. Treatments for HIV-associated pain and peripheral sensory neuropathies currently consist of symptomatic management, but a greater understanding of their pathogenesis can lead to the development of targeted molecular therapies and disease-modifying therapies. HIV-associated autonomic dysfunction may affect the course of systemic disease via disrupted neuro-immune interactions; however, more research is needed to facilitate our understanding of how these processes present clinically.

Toward Safer Opioid Prescribing in HIV care (TOWER): a mixed-methods, cluster-randomized trial.

BACKGROUND: The 2016 U.S. Centers for Disease Control Opioid Prescribing Guideline (CDC Guideline) is currently being revised amid concern that it may be harmful to people with chronic pain on long-term opioid therapy (CP-LTOT). However, a methodology to faithfully implement the CDC guideline, measure prescriber adherence, and systematically test its effect on patient and public health outcomes is lacking. We developed and tested a CDC Guideline implementation strategy (termed TOWER), focusing on an outpatient HIV-focused primary care setting. METHODS: TOWER was developed in a stakeholder-engaged, multi-step iterative process within an Information, Motivation and Behavioral Skills (IMB) framework of behavior change. TOWER consists of: 1) a patient-facing opioid management app (OM-App); 2) a progress note template (OM-Note) to guide the office visit; and 3) a primary care provider (PCP) training. TOWER was evaluated in a 9-month, randomized-controlled trial of HIV-PCPs (N = 11) and their patients with HIV and CP-LTOT (N = 40). The primary outcome was CDC Guideline adherence based on electronic health record (EHR) documentation and measured by the validated Safer Opioid Prescribing Evaluation Tool (SOPET). Qualitative data including one-on-one PCP interviews were collected. We also piloted patient-reported outcome measures (PROMs) reflective of domains identified as important by stakeholders (pain intensity and function; mood; substance use; medication use and adherence; relationship with provider; stigma and discrimination). RESULTS: PCPs randomized to TOWER were 48% more CDC Guideline adherent (p < 0.0001) with significant improvements in use of: non-pharmacologic treatments, functional treatment goals, opioid agreements, prescription drug monitoring programs (PDMPs), opioid benefit/harm assessment, and naloxone prescribing. Qualitative data demonstrated high levels of confidence in conducting these care processes among intervention providers, and that OM-Note supported these efforts while experience with OM-App was mixed. There were no intervention-associated safety concerns (defined as worsening of any of the PROMs). CONCLUSIONS: CDC-guideline adherence can be promoted and measured, and is not associated with worsening of outcomes for people with HIV receiving LTOT for CP. Future work would be needed to document scalability of these results and to determine whether CDC-guideline adherence results in a positive effect on public health. Trial registration https://clinicaltrials.gov/ct2/show/NCT03669939 . Registration date: 9/13/2018.

Prevalence of Treatment Burden in the Last Three Years of Life.

Background: Little is known about the experience of treatment burden, or the difficulties that arise when the treatment workload overwhelms one's ability to take on treatment activities, at the end of life. Objective: We first assessed rates of treatment burden experienced by all older adults in the last three years of life. Among the subset of our sample who had multiple chronic conditions (MCCs), we determined correlates of treatment burden with sociodemographic, health, and caregiving factors. Design: We conducted a cross-sectional study using nationally representative data from the National Health and Aging Trends Study (NHATS). Setting/Subjects: Our sample included 356 adults, aged 65 years and older, who died within three years of completing the 2012 NHATS Treatment Burden Questionnaire. Our MCC cohort included only those in our sample with two or more chronic conditions. Measurements: Our measure of treatment burden included reports of difficulty in managing treatment activities, delays in treatments, or feeling that physicians asked for too much. We built a composite measure to identify burden if participants reported that at least one item occurred sometimes or often. Results: Forty-three percent of older adults in their last three years of life experienced treatment burden. Among individuals with MCCs, bivariate analysis found that treatment burden was associated with being a racial minority and having depression, anxiety, and a cancer diagnosis. These associations were not statistically significant in a multivariable model. Conclusion: Treatment burden is a common experience among older adults regardless of sociodemographic, clinical, and caregiving factors.

Adolescent Changes in Cellular Proliferation in the Dentate Gyrus of Male and Female C57BL/6N Mice Are Resilient to Chronic Oral Corticosterone Treatments.

Adolescent development is marked by significant changes in neurobiological structure and function. One such change is the substantial adolescent-related decline in cellular proliferation and neurogenesis in the dentate gyrus of the hippocampal formation. Though the behavioral implications of these developmental shifts in cell proliferation are unclear, these changes might contribute to the altered cognitive and emotional functions associated with puberty and adolescence. The significant decrease in cellular proliferation throughout adolescence might make the hippocampus more vulnerable to perturbations during this developmental stage, particularly to factors known to disrupt neurogenesis, such as chronic exposure to stress-related hormones. To examine this possibility, we first measured cellular proliferation in the dentate gyrus of male and female C57BL/6N mice before and after adolescence and then assessed both cellular proliferation and the number of immature neurons in mice treated with oral corticosterone for 4 weeks during either adolescence or adulthood. We found significant age-related decreases in hippocampal cellular proliferation in both males and females. Though the greatest decrease in proliferation was during adolescence, we also observed that proliferation continued to decline through young adulthood. Despite the significant effect of chronic oral corticosterone on body weight gain in both the adolescent- and adult-treated males and females and the subtle, but significant suppressive effect of corticosterone on the number of immature neurons in the adolescent-treated males, cell proliferation in the hippocampus was unaffected by these treatments. These data show that the substantial adolescent-related change in cellular proliferation in the dentate gyrus is largely unaffected by chronic oral corticosterone exposure in males and females. Thus, despite being vulnerable to the metabolic effects of these chronic corticosterone treatments, these results indicate that the developmental changes in cellular proliferation in the dentate gyrus are relatively resilient to these treatments in mice.