Publications by authors named "RW Johnson"

Studies using acute or subchronic pharmacological inhibition of phosphodiesterase 2 A (PDE2A) have led to its proposal as a target for treatment of cognitive deficits associated with neuropsychiatric and neurodegenerative disease. However, the impact of continuous inhibition of PDE2A on memory is unknown. Moreover, the neuroanatomical regions mediating memory enhancement have not been categorically identified.

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  • The lone star tick's range has increased in the northeastern USA, now overlapping with the blacklegged tick, which carries serious diseases like Lyme disease.
  • Research on Martha's Vineyard from 2011 to 2024 showed the expansion of lone star ticks from certain areas to all six towns, coinciding with more tick submissions for pathogen testing.
  • While blacklegged ticks were slightly more common in wooded areas, lone star ticks were found in a broader variety of habitats, complicating prevention and management efforts for the public.
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Peripheral viral infection disrupts oligodendrocyte (OL) homeostasis such that endogenous remyelination may be affected. Here, we demonstrate that influenza A virus infection perpetuated a demyelination- and disease-associated OL phenotype following cuprizone-induced demyelination that resulted in delayed OL maturation and remyelination in the prefrontal cortex. Furthermore, we assessed cellular metabolism , and found that infection altered brain OL and microglia metabolism in a manner that opposed the metabolic profile induced by remyelination.

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Gut inflammation can trigger neuroinflammation and is linked to mood disorders. Microbiota-derived short-chain fatty acids (SCFAs) can modulate microglia, yet the mechanism remains elusive. Since microglia do not express free-fatty acid receptor (FFAR)2, but intestinal epithelial cells (IEC) and peripheral myeloid cells do, we hypothesized that SCFA-mediated FFAR2 activation within the gut or peripheral myeloid cells may impact microglia inflammation.

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  • DNA methylation is an epigenetic change that influences gene expression, with effects varying by developmental stage, inflammation, and sex.
  • In a pig model, researchers examined how maternal viral infection and sex affect DNA methylation patterns in the hypothalamus, identifying 120 differentially methylated sites linked to various biological processes.
  • Findings indicate that maternal infection can lead to significant long-term epigenetic changes that differ between males and females, potentially impacting immune response and other developmental processes.
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The role of parathyroid hormone (PTH)-related protein (PTHrP) in breast cancer remains controversial, with reports of PTHrP inhibiting or promoting primary tumor growth in preclinical studies. Here, we provide insight into these conflicting findings by assessing the role of specific biological domains of PTHrP in tumor progression through stable expression of PTHrP (-36-139aa) or truncated forms with deletion of the nuclear localization sequence (NLS) alone or in combination with the C-terminus. Although the full-length PTHrP molecule (-36-139aa) did not alter tumorigenesis, PTHrP lacking the NLS alone accelerated primary tumor growth by downregulating p27, while PTHrP lacking the NLS and C-terminus repressed tumor growth through p27 induction driven by the tumor suppressor leukemia inhibitory factor receptor (LIFR).

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Epigenetic alterations, including DNA methylation and post translational modifications to histones, drive tumorigenesis and metastatic progression. In the context of bone metastasis, epigenetic modifications in tumor cells can modulate dissemination of cancer cells to the bone, tumor progression in the bone marrow, and may be associated with patient survival rates. Bone disseminated tumor cells may enter a dormant state or stimulate osteolysis through the "vicious cycle" of bone metastasis where bone disseminated tumor cells disrupt the bone microenvironment, which fuels tumor progression.

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The hypothalamic molecular processes participate in the regulation of the neuro-immune-endocrine system, including hormone, metabolite, chemokine circulation, and corresponding physiological and behavioral responses. RNA-sequencing profiles were analyzed to understand the effect of juvenile immune and metabolic distress 100 days after virally elicited maternal immune activation during gestation in pigs. Over 1,300 genes exhibited significant additive or interacting effects of gestational immune activation, juvenile distress, and sex.

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This study aimed to improve our understanding of how the hypothalamus mediates the effects of prenatal and postnatal challenges on behavior and sensitivity to stimuli. A pig model of virally initiated maternal immune activation (MIA) was used to investigate potential interactions of the prenatal challenge both with sex and with postnatal nursing withdrawal. The hypothalami of 72 females and males were profiled for the effects of MIA and nursing withdrawal using RNA-sequencing.

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Immune checkpoint inhibitors (ICIs) have revolutionized the field of anti-cancer therapy over the last decade; they provide durable clinical responses against tumors by inhibiting immune checkpoint proteins that canonically regulate the T cell-mediated immune response. Despite their success in many primary tumors and soft tissue metastases, ICIs function poorly in patients with bone metastases, and these patients do not have the same survival benefit as patients with the same primary tumor type (e.g.

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  • The study aimed to evaluate the feasibility of the Zingo app, a gamified therapy tool for children with neurodisability, in delivering therapy programs at school and home.
  • A mixed-methods approach was used, involving 8 children and their parents, therapists, and teachers over a 4-week therapy program, measuring adherence, engagement, app quality, and user experience.
  • Results showed a 58% adherence rate with a solid engagement score of 74%, and high app quality ratings (around 4.5 out of 5) from parents and educators, suggesting Zingo can motivate children to complete therapy programs despite challenges like the COVID-19 outbreak.
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  • - Prenatal stress can lead to maternal immune activation (MIA), affecting brain development and metabolism, with lasting effects that may manifest later in life.
  • - A study using a pig model revealed that both MIA and postnatal stress significantly influenced fifty-nine hippocal metabolites, with some showing interactive effects, impacting important pathways in metabolism and brain function.
  • - The findings suggest that prenatal and postnatal stressors may disrupt metabolic pathways linked to neuroinflammation, supporting the "double-hit hypothesis," which indicates that prior MIA can worsen the effects of later stress on brain health.
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Parathyroid-hormone-related protein (PTHrP) is a protein with a long history of association with bone metastatic cancers. The paracrine signaling of PTHrP through the parathyroid hormone receptor (PTHR1) facilitates tumor-induced bone destruction, and PTHrP is known as the primary driver of humoral hypercalcemia of malignancy. In addition to paracrine signaling, PTHrP is capable of intracrine signaling independent of PTHR1 binding, which is essential for cytokine-like functions in normal physiological conditions in a variety of tissue types.

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The complexity of new therapeutics continues to increase and the timeline for the discovery of these therapeutics continues to shrink. This creates demand for new analytical techniques to facilitate quicker discovery and development of novel drugs. Mass spectrometry is one of the most prolific analytical techniques that has been applied across the entire drug discovery pipeline.

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Immune challenges during gestation are associated with neurodevelopmental disorders and can interact with stress later in life. The pituitary gland participates in endocrine- and immune-related processes that influence development, growth, and reproduction and can modulate physiological and behavioral responses to challenges. The objective of this study was to investigate the effect of stressors at different time points on the molecular mechanisms of the pituitary gland and detect sex differences.

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Due to the increasing human life expectancy and limited supply of healthcare resources, strategies to promote healthy aging and reduce associated functional deficits are of public health importance. The gut microbiota, which remodels with age, has been identified as a significant contributor to the aging process that is modifiable by diet. Since prebiotic dietary components such as inulin have been shown to impart positive benefits with regards to aging, this study used C57Bl6 mice to investigate whether 8 weeks on a 2.

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Breast cancer has a high predilection for spreading to bone with approximately 70% of patients who succumb to disease harboring bone disseminated tumor cells. Despite this high prevalence, treatments for bone metastatic breast cancer predominantly manage morbidities, including pain and hypercalcemia, rather than reducing bone metastasis incidence or growth. Histone deacetylase inhibitors (HDACi), including panobinostat, entinostat, and valproic acid, typically slow primary tumor progression and are currently in clinical trials for the treatment of many cancers, including primary and metastatic breast cancer, but their effects on bone metastatic disease have not been examined in preclinical models.

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Microglia play a vital role maintaining brain homeostasis but can also cause persistent neuroinflammation. Short-chain fatty acids (SCFAs) produced by the intestinal microbiota have been suggested to regulate microglia inflammation indirectly by signaling through the gut-brain axis or directly by reaching the brain. The present work evaluated the anti-inflammatory effects of SCFAs on lipopolysaccharide (LPS)-stimulated microglia from mice fed inulin, a soluble fiber that is fermented by intestinal microbiota to produce SCFAs in vivo, and SCFAs applied to primary microglia in vitro.

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  • The hippocampus is key for spatial navigation and can be affected by environmental and inflammatory challenges during prenatal and postnatal stages, potentially leading to neuropsychiatric issues.
  • A study using a pig model examined the effects of maternal immune activation (MIA) on the hippocampal gene expression of offspring, revealing over 2600 genes influenced by factors like stress, sex, and treatments (fasting, viral mimetics, saline).
  • The research indicates that environmental challenges can interact in complex ways, with some prenatal effects being negated by postnatal stress, highlighting potential molecular targets for addressing stress-related impacts on hippocampal function.
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Teriparatide, recombinant parathyroid hormone (PTH[1-34]), and abaloparatide, an analogue of PTH related-peptide (PTHrP[1-34]), are both anabolic medications for osteoporosis that target the PTH receptor PTH1R. PTH1R is a G protein-coupled receptor, and the stimulatory Gs protein is an important mediator of the anabolic actions of PTH1R activation in bone. We have published that mice lacking the α subunit of Gs in osteoprogenitors do not increase bone mass in response to PTH(1-34).

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Purpose: Endurance exercise alters the gut microbiome independently of diet. The extent to which gut microbes are responsible for physiologic adaptations to exercise training is unknown. The purpose of these experiments was to determine the role of gut microbes in performance and muscle adaptation to 6 wk of voluntary wheel running (VWR) in mice.

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  • The study investigates how maternal immune activation (MIA) and morphine exposure affect brain pathways in a pig model, focusing on the prefrontal cortex of both sexes.
  • Researchers used RNA-sequencing to analyze about 2000 genes, revealing significant interactions between morphine, MIA, and sex, particularly in pathways related to inflammation and neuronal development.
  • Findings indicate that the combined impact of morphine and MIA is less extreme than that of individual exposures, providing new insights into how prenatal and postnatal challenges influence brain molecular mechanisms.
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Objective: To determine whether initiating saline nasal irrigation after COVID-19 diagnosis reduces hospitalization and death in high-risk outpatients compared with observational controls, and if irrigant composition impacts severity.

Methods: Participants 55 and older were enrolled within 24 hours of a + PCR COVID-19 test between September 24 and December 21, 2020. Among 826 screened, 79 participants were enrolled and randomly assigned to add 2.

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Parathyroid hormone-related protein (PTHrP) was discovered as the tumor product causing the humoral hypercalcemia of malignancy. Its structural similarity to the hormone, PTH, with 8 of the first 13 amino acids identical, was sufficient to explain the sharing by PTHrP and PTH of a common receptor, PTH1R, although the remainder of the sequences are unique. PTHrP has important roles in development of several organs, including breast and bone, and functions as a paracrine factor postnatally in these and other tissues.

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