Browsing by Author "Pediatrics, School of Medicine"
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Item 1,25-Dihydroxyvitamin D3 enhances glucose-stimulated insulin secretion in mouse and human islets: a role for transcriptional regulation of voltage-gated calcium channels by the vitamin D receptor(Elsevier, 2018) Kjalarsdottir, Lilja; Tersey, Sarah A.; Vishwanath, Mridula; Chuang, Jen-Chieh; Posner, Bruce A.; Mirmira, Raghavendra G.; Repa, Joyce J.; Pediatrics, School of MedicineAim Vitamin D deficiency in rodents negatively affects glucose-stimulated insulin secretion (GSIS) and human epidemiological studies connect poor vitamin D status with type 2 diabetes. Previous studies performed primarily in rat islets have shown that vitamin D can enhance GSIS. However the molecular pathways linking vitamin D and insulin secretion are currently unknown. Therefore, experiments were undertaken to elucidate the transcriptional role(s) of the vitamin D receptor (VDR) in islet function. Methods Human and mouse islets were cultured with vehicle or 1,25-dihydroxyvitamin-D3 (1,25D3) and then subjected to GSIS assays. Insulin expression, insulin content, glucose uptake and glucose-stimulated calcium influx were tested. Microarray analysis was performed. In silico analysis was used to identify VDR response elements (VDRE) within target genes and their activity was tested using reporter assays. Results Vdr mRNA is abundant in islets and Vdr expression is glucose-responsive. Preincubation of mouse and human islets with 1,25D3 enhances GSIS and increases glucose-stimulated calcium influx. Microarray analysis identified the R-type voltage-gated calcium channel (VGCC) gene, Cacna1e, which is highly upregulated by 1,25D3 in human and mouse islets and contains a conserved VDRE in intron 7. Results from GSIS assays suggest that 1,25D3 might upregulate a variant of R-type VGCC that is resistant to chemical inhibition. Conclusion These results suggest that the role of 1,25D3 in regulating calcium influx acts through the R-Type VGCC during GSIS, thereby modulating the capacity of beta cells to secrete insulin.Item 100 years of insulin: celebrating the past, present and future of diabetes therapy(Springer Nature, 2021) Sims, Emily K.; Carr, Alice L.J.; Oram, Richard A.; DiMeglio, Linda A.; Evans-Molina, Carmella; Pediatrics, School of MedicineThe year 2021 marks the centennial of Banting and Best's landmark description of the discovery of insulin. This discovery and insulin's rapid clinical deployment effectively transformed type 1 diabetes from a fatal diagnosis into a medically manageable chronic condition. In this Review, we describe key accomplishments leading to and building on this momentous occasion in medical history, including advancements in our understanding of the role of insulin in diabetes pathophysiology, the molecular characterization of insulin and the clinical use of insulin. Achievements are also viewed through the lens of patients impacted by insulin therapy and the evolution of insulin pharmacokinetics and delivery over the past 100 years. Finally, we reflect on the future of insulin therapy and diabetes treatment, as well as challenges to be addressed moving forward, so that the full potential of this transformative discovery may be realized.Item 11. Changes in Adolescent and Young Adult (AYA) Relationship Status during COVID19: Data from a 30 Country Sexual and Reproductive Health Study(Elsevier, 2022) Hensel, Devon J.; Campbell, Linda; Erausquin, Jennifer T.; Mark, Kristin P.; I-SHARE Consortium; Pediatrics, School of MedicinePurpose: Important milestones - including romantic/sexual relationship development - were impacted by COVID19 mitigation measures. We examined self-reported change in relationship status before, during and after COVID among AYA who participated in a 30-country survey. Methods: Data were drawn from the International Sexual Health And REproductive Health Survey (I-SHARE-1), a multi-country, cross-sectional, online study conducted to assess the impact of the pandemic on adult sexual health across the globe. Participants were recruited through local, regional, and national networks (e.g. listservs of professional organizations and international health organizations, social media, etc.) of each country’s research team. We drew a subsample of AYA (N=7527 18-26 years; 32.3% of the total sample; 60.1% female, 86.1% cisgender, 77.1% heterosexual). We examined 5 categories of relationship status change: 1) unpartnered pre/post; 2) unpartnered pre, new partner post; 3) same partner pre/post; 4) partnered pre, broke up, unpartnered post; 5) partnered pre, broke up, new partner post. Random intercept mixed effects multinomial regression (gllamm; Stata 17.0; all p<.05) adjusted for country-level clustering was used to understand how demographic (age, gender identity, sexual identity, employment status during COVID, mental health, distancing or isolation during COVID) and country-level predictors (income group, Oxford Stringency Index [national response to COVID], Palma Ratio [country-income inequality) and Gender Inequality Index (country-gender inequality) were associated with relationship change. Results: 15% of AYA had no partner pre/post COVID, 5% were unpartnered pre-COVID with new partner post. 63.3% had the same partner pre/post, whereas 11.3% had a partner pre-COVID, but broke up and had no new partner post-COVID. Less than 5% had a new partner post-COVID after breaking up with their pre-COVID partner. Of those who broke up with their partner, the majority ended during (44.4%) or after (26.6%) COVID-lockdowns, and one-third thought social distancing precipitated the relationship’s end. Older (RRR=0.86-0.91), female (RRR=0.32-0.63) and transgender AYA (RRR=0.10-0.37) all had a lower risk, and sexual minority AYA had a higher risk (RRR=1.35-1.51), of being in all status categories compared to being in the same relationship before-and-after COVID. Higher mental health scores were linked to lower probability of being unpartnered pre/post as compared to being partnered pre/post (RRR=0.89-0.82). Social-distancing was associated with a lower risk for pre-COVID unpartnered individuals finding new post-COVID relationships (RRR=0.76) or of partnered individuals breaking up, while ever being in isolation was associated with higher risk of being unpartnered pre/post (RRR=1.20). Higher country income was associated with being unpartered pre-COVID (RRR=0.08-0.12) and higher risk of having a pre-COVID relationship break-up (RRR=1.32). Unpartnered individuals in countries with higher lockdown stringency had a greater probability of finding a new post-COVID relationship (RRR=1.13). Conclusions: COVID measures were associated with AYA relationships both initiating and ending. Strategies for relationship development/support should be included as part of preparation for future public health emergencies.Item 12-Lipoxygenase governs the innate immune pathogenesis of islet inflammation and autoimmune diabetes(The American Society for Clinical Investigation, 2021-07-22) Kulkarni, Abhishek; Pineros, Annie R.; Walsh, Melissa A.; Casimiro, Isabel; Ibrahim, Sara; Hernandez-Perez, Marimar; Orr, Kara S.; Glenn, Lindsey; Nadler, Jerry L.; Morris, Margaret A.; Tersey, Sarah A.; Mirmira, Raghavendra G.; Anderson, Ryan M.; Pediatrics, School of MedicineMacrophages and related myeloid cells are innate immune cells that participate in the early islet inflammation of type 1 diabetes (T1D). The enzyme 12-lipoxygenase (12-LOX) catalyzes the formation of proinflammatory eicosanoids, but its role and mechanisms in myeloid cells in the pathogenesis of islet inflammation have not been elucidated. Leveraging a model of islet inflammation in zebrafish, we show here that macrophages contribute significantly to the loss of β cells and the subsequent development of hyperglycemia. The depletion or inhibition of 12-LOX in this model resulted in reduced macrophage infiltration into islets and the preservation of β cell mass. In NOD mice, the deletion of the gene encoding 12-LOX in the myeloid lineage resulted in reduced insulitis with reductions in proinflammatory macrophages, a suppressed T cell response, preserved β cell mass, and almost complete protection from the development of T1D. 12-LOX depletion caused a defect in myeloid cell migration, a function required for immune surveillance and tissue injury responses. This effect on migration resulted from the loss of the chemokine receptor CXCR3. Transgenic expression of the gene encoding CXCR3 rescued the migratory defect in zebrafish 12-LOX morphants. Taken together, our results reveal a formative role for innate immune cells in the early pathogenesis of T1D and identify 12-LOX as an enzyme required to promote their prodiabetogenic phenotype in the context of autoimmunity.Item 12-Lipoxygenase Inhibitor Improves Functions of Cytokine-Treated Human Islets and Type 2 Diabetic Islets(Oxford University Press, 2017-08-01) Ma, Kaiwen; Xiao, An; Park, So Hyun; Glenn, Lindsey; Jackson, Laura; Barot, Tatvam; Weaver, Jessica R.; Taylor-Fishwick, David A.; Luci, Diane K.; Maloney, David J.; Mirmira, Raghavendra G.; Imai, Yumi; Nadler, Jerry L.; Pediatrics, School of MedicineContext: The 12-lipoxygenase (12-LO) pathway produces proinflammatory metabolites, and its activation is implicated in islet inflammation associated with type 1 and type 2 diabetes (T2D). Objectives: We aimed to test the efficacy of ML355, a highly selective, small molecule inhibitor of 12-LO, for the preservation of islet function. Design: Human islets from nondiabetic donors were incubated with a mixture of tumor necrosis factor α , interluekin-1β, and interferon-γ to model islet inflammation. Cytokine-treated islets and human islets from T2D donors were incubated in the presence and absence of ML355. Setting: In vitro study. Participants: Human islets from organ donors aged >20 years of both sexes and any race were used. T2D status was defined from either medical history or most recent hemoglobin A1c value >6.5%. Intervention: Glucose stimulation. Main Outcome Measures: Static and dynamic insulin secretion and oxygen consumption rate (OCR). Results: ML355 prevented the reduction of insulin secretion and OCR in cytokine-treated human islets and improved both parameters in human islets from T2D donors. Conclusions: ML355 was efficacious in improving human islet function after cytokine treatment and in T2D islets in vitro. The study suggests that the blockade of the 12-LO pathway may serve as a target for both form of diabetes and provides the basis for further study of this small molecule inhibitor in vivo.Item A 12-lipoxygenase-Gpr31 signaling axis is required for pancreatic organogenesis in the zebrafish(Wiley, 2020-11) Hernandez-Perez, Marimar; Kulkarni, Abhishek; Samala, Niharika; Sorrell, Cody; El, Kimberly; Haider, Isra; Aleem, Ansari Mukhtar; Holman, Theodore R.; Rai, Ganesha; Tersey, Sarah A.; Mirmira, Raghavendra G.; Anderson, Ryan M.; Pediatrics, School of Medicine12-Lipoxygenase (12-LOX) is a key enzyme in arachidonic acid metabolism, and alongside its major product, 12-HETE, plays a key role in promoting inflammatory signaling during diabetes pathogenesis. Although 12-LOX is a proposed therapeutic target to protect pancreatic islets in the setting of diabetes, little is known about the consequences of blocking its enzymatic activity during embryonic development. Here, we have leveraged the strengths of the zebrafish-genetic manipulation and pharmacologic inhibition-to interrogate the role of 12-LOX in pancreatic development. Lipidomics analysis during zebrafish development demonstrated that 12-LOX-generated metabolites of arachidonic acid increase sharply during organogenesis stages, and that this increase is blocked by morpholino-directed depletion of 12-LOX. Furthermore, we found that either depletion or inhibition of 12-LOX impairs both exocrine pancreas growth and unexpectedly, the generation of insulin-producing β cells. We demonstrate that morpholino-mediated knockdown of GPR31, a purported G-protein-coupled receptor for 12-HETE, largely phenocopies both the depletion and the inhibition of 12-LOX. Moreover, we show that loss of GPR31 impairs pancreatic bud fusion and pancreatic duct morphogenesis. Together, these data provide new insight into the requirement of 12-LOX in pancreatic organogenesis and islet formation, and additionally provide evidence that its effects are mediated via a signaling axis that includes the 12-HETE receptor GPR31.Item 143 Training & Sustaining: Training and learning collaborative outcomes across a statewide network for early diagnosis of children with autism(Cambridge University Press, 2024-04-03) McNally Keehn, Rebecca; Paxton, Angela; Delaney, Mary; Ciccarelli, Mary; Pediatrics, School of MedicineOBJECTIVES/GOALS: Community-based primary care autism diagnostic models are one promising solution to delays in autism diagnosis. Our objective is to describe the development and report on outcomes related to primary care professional (PCP) training and sustained engagement in a longitudinal learning collaborative across a statewide network for autism diagnosis. METHODS/STUDY POPULATION: We developed ADAPT (i.e., Accelerating the Diagnosis of Autism with Primary care Training), a training program to prepare PCPs to develop independent competency in evaluation of autism in children ages 14-48 months. ADAPT includes didactic and case-based modules and expert practice-based coaching delivered by a diagnostic specialist; following training PCPs participate in a longitudinal learning collaborative. Aligned with competency-based medical education standards, measures of autism evaluation knowledge and diagnostic competency are collected. RESULTS/ANTICIPATED RESULTS: To date, 13 PCPs have completed ADAPT didactic and practicum training reaching competency in independent autism evaluation. Clinicians demonstrated significant improvement in total autism knowledge following didactic training (p=.02). There was an overall trend toward increased scoring agreement on an autism observational assessment over case observations and practicum evaluations. Similarly, PCPs demonstrated improved evaluation competence, moving on average from Advanced Beginner to Competent Performer as rated by expert trainers. Following training, PCPs attended 57% of monthly learning collaborative sessions. DISCUSSION/SIGNIFICANCE: Training PCPs to deliver autism evaluations as part of community-based models of care is a promising solution to address access and waitlist challenges. ADAPT is an intensive, standard PCP training model which results in achievement of independent competency and sustained engagement in in autism evaluation.Item 15-Lipoxygenase worsens renal fibrosis, inflammation, and metabolism in a murine model of ureteral obstruction(American Physiological Society, 2022) Montford, John R.; Bauer, Colin; Rahkola, Jeremy; Reisz, Julie A.; Floyd, Deanna; Hopp, Katharina; Soranno, Danielle E.; Klawitter, Jelena; Weiser-Evans, Mary C. M.; Nemenoff, Raphael; Faubel, Sarah; Furgeson, Seth B.; Pediatrics, School of Medicine15-Lipoxygenase (15-LO) is a nonheme iron-containing dioxygenase that has both pro- and anti-inflammatory roles in many tissues and disease states. 15-LO is thought to influence macrophage phenotype, and silencing 15-LO reduces fibrosis after acute inflammatory triggers. The goal of the present study was to determine whether altering 15-LO expression influences inflammation and fibrogenesis in a murine model of unilateral ureteral obstruction (UUO). C57BL/6J mice, 15-LO knockout (Alox15-/-) mice, and 15-LO transgenic overexpressing (15LOTG) mice were subjected UUO, and kidneys were analyzed at 3, 10, and 14 days postinjury. Histology for fibrosis, inflammation, cytokine quantification, flow cytometry, and metabolomics were performed on injured tissues and controls. PD146176, a specific 15-LO inhibitor, was used to complement experiments involving knockout animals. Compared with wild-type animals undergoing UUO, Alox15-/- mouse kidneys had less proinflammatory, profibrotic message along with less fibrosis and macrophage infiltration. PD146176 inhibited 15-LO and resulted in reduced fibrosis and macrophage infiltration similar to Alox15-/- mice. Flow cytometry revealed that Alox15-/- UUO-injured kidneys had a dynamic change in macrophage phenotype, with an early blunting of CD11bHiLy6CHi "M1" macrophages and an increase in anti-inflammatory CD11bHiLy6CInt "M2c" macrophages and reduced expression of the fractalkine receptor chemokine (C-X3-C motif) receptor 1. Many of these findings were reversed when UUO was performed on 15LOTG mice. Metabolomics analysis revealed that wild-type kidneys developed a glycolytic shift postinjury, while Alox15-/- kidneys exhibited increased oxidative phosphorylation. In conclusion, 15-LO manipulation by genetic or pharmacological means induces dynamic changes in the inflammatory microenvironment in the UUO model and appears to be critical in the progression of UUO-induced fibrosis. NEW & NOTEWORTHY: 15-Lipoxygenase (15-LO) has both pro- and anti-inflammatory functions in leukocytes, and its role in kidney injury and repair is unexplored. Our study showed that 15-LO worsens inflammation and fibrosis in a rodent model of chronic kidney disease using genetic and pharmacological manipulation. Silencing 15-LO promotes an increase in M2c-like wound-healing macrophages in the kidney and alters kidney metabolism globally, protecting against anaerobic glycolysis after injury.Item 153. AYA Subspecialty Patient and Parent Views on COVID-19 Vaccination(Elsevier, 2022) Hardman, Sara; Jacob, Seethal A.; Coven, Scott L.; Rahim, Mahvish Q.; Miller, Meagan E.; Zimet, Gregory D.; Meagher, Carolyn G.; Ott, Mary A.; Pediatrics, School of MedicinePurpose: Adolescents/young adults (AYA) with hematologic and oncologic (heme-onc) conditions are important targets for vaccine outreach because they are at increased risk for complications from COVID-19. AYA patients may also need additional support, as they are transitioning from parent to independent vaccine decision-making. AYA with sickle cell disease (SCD) are of particular concern because a high proportion are African American and experience structural racism in addition to their illness. Our objective was to examine AYA and parent attitudes regarding the COVID-19 vaccine among heme-onc populations. Methods: As part of a larger IRB-approved study, we recruited vaccine decision-makers in pediatric SCD and oncology survivor clinics, including parents of adolescents under 18 years (n=35), AYA patients 18-21 years old (n=21), and parents of AYA patients 18-21 years old (n=14). After informed consent, participants completed a demographic survey and a semi-structured interview regarding their vaccine decision-making process. Example questions included “What do you see as the benefits of the COVID-19 vaccine?” and “What are your concerns about the COVID-19 vaccine?”. Saturation was reached. Interviews were audio recorded, transcribed, and analyzed using thematic analysis. Codes were developed from the literature and early interviews. Examples included “attitudes against vaccine,” “medical mistrust,” “hesitancy,” “vaccine side effects,” and “vaccine interactions with disease process.” Fisher exact statistical tests were performed to analyze quantitative data. Results: In SCD clinic, we recruited 31 index patients (mean age: 15.1±3.5 years; 30 African American and 1 Other or Mixed), yielding 11 AYA and 26 parent interviews. In survivor clinic, we recruited 26 index patients (mean age: 16.0±3.4 years; 20 White, 2 Hispanic or Latinx; 2 Other or Mixed, 1 African American, and 1 Asian), yielding 10 AYA and 23 parent interviews. Out of the total index patients, 8 had already received the vaccine, 13 were planning to receive it, 27 were considering it, and 9 had declined it. There was no clear relationship between patients’ diagnosis (SCD or cancer) and their vaccine decisions nor between the index patient’s age (under or over 18) and their vaccine decisions. A high proportion of participants saw benefits to vaccination, such as lowering personal risk, community benefits of preventing the spread of COVID-19, and a possible return to “normal.” However, many AYA and parent participants also had concerns toward the vaccine, including concerns about short-term side effects and the potential for unknown, long-term effects. Concerns were also voiced about how rapidly the vaccine was developed and misconceptions about the vaccine were common, namely the vaccine causing infertility or increasing one’s susceptibility to contracting COVID-19. Medical mistrust toward either the vaccine or providers was explicitly stated by several participants, the majority of whom were from minoritized groups. Conclusions: COVID-19 vaccines have the potential to protect medically and socially vulnerable AYA, however patient and parent concerns, misconceptions, and mistrust are still prevalent. These data provide insights into the design and implementation of vaccine counseling interviews for AYA subspecialty patients and families.Item 156. Daily Association of Drug Use Cravings and Physical and Emotional Well-Being among Students Attending a Recovery High School during COVID-19: Results from an EMA Study(Elsevier, 2023) Hensel, Devon J.; Wilburn, Victoria Garcia; Pediatrics, School of MedicinePurpose: Ongoing COVID-19 restrictions are now well-known to increase youth substance use. Little research has addressed this vulnerability among adolescents in substance use recovery (AIR), who may be at heightened risk for relapse within ongoing pandemic management. We used ecological momentary assessment-focused (EMA) to characterize daily shifts in recovery management among adolescents attending a recovery high school. We engage the first wave of these EMA-data collected during third wave of the pandemic (January-February 2022) to: 1) document day-to-day changes in drug craving context (e.g., frequency, temporality, duration, and intensity) and; 2) examine its association with daily shifts in physical and emotional well-being. Methods: Data were from an EMA-study (ongoing through 2022-2023 school-year) intended to understand the social/emotional context of drug use cravings among a cohort of AIR attending a recovery high school in Indianapolis, IN. Our analytic-sample includes six-students (N=40 total) who were enrolled during the second pandemic wave (57.3% female, 42.5% heterosexual, 71.0% White, 52.3% 12th-grade, 57.4% had weekly urges use). Drug use context measures: any drug-use urge (no/yes), urge frequency (5-point item: once-6+ times), urge temporality/duration (6-point item: AM, aft or PM only, more than half the day, all day) and urge intensity (single item: 0-10). Physical and emotional variables: emotional pain (5-point single item: not at all-extremely), self-perceived health (5-point single item: poor to excellent), positive and negative mood (PANAS) and somatic symptoms (summed 12-point: all no/yes). Descriptive statistics and intraclass correlation coefficients (ICC) examined the prevalence and day-to-day variability of each outcome; random intercept mixed effects binary or ordinal regression assessed the impact of physical and emotional predictors on each outcome (Stata v. 18). Results: Participants contributed 81.2% (147/180) of expected EMAs, one-third of which were associated with an urge to use drugs. 6% of urge days also involved a report of drug-use (4/48; ns sample size for additional-analysis). Median within-day urge frequency was 3-5x/day (35.3% of all urge events). We observed significant day-to-day variability in reports of drug urges and the intensity of urges (ICC: 0.209-0.601), but not in temporality and duration of urges. Greater daily emotional pain nearly quadrupled the odds of reporting having drug urges (OR=3.75) and was associated with three-fold higher within-day urge frequency (OR=2.42) and urge intensity (OR=2.92). Higher positive mood was positively associated with urge to use (OR=1.36), urge frequency (OR=1.17) and urge intensity (OR=1.18). More somatic symptoms were associated with greater odds of having drug urges (OR=1.26) and urge frequency during the day (OR=1.10). Conclusions: Our research demonstrates that daily emotional valence and greater somatic symptoms are associated with daily drug urge occurrence, daily urge frequency and daily drug urge intensity among AIR. These EMA data have important clinical implications for “just in time” mental and behavioral health interventions that could focus on mood stability and physical wellness as scaffolds in adolescent recovery management.