School of Medicine

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Insulin is an important regulator of whole-body glucose homeostasis. In insulin sensitive tissues such as muscle and adipose, insulin induces the translocation of glucose transporter 4 (GLUT4) to the cell membrane, thereby increasing glucose uptake. However, insulin also signals in tissues that are not generally associated with glucose homeostasis. In the human reproductive endocrine axis, hyperinsulinemia suppresses the secretion of gonadotropins from gonadotrope cells of the anterior pituitary, thereby linking insulin dysregulation to suboptimal reproductive health. In the mouse, gonadotropes express the insulin receptor which has the canonical signaling response of IRS, AKT, and mTOR activation. However, the functional outcomes of insulin action on gonadotropes are unclear. Here, we demonstrate through use of an optimized cell fractionation protocol that insulin stimulation of the LβT2 gonadotropic cell line results in the unexpected translocation of GLUT1 to the plasma membrane. Using our high purity fractionation protocol, we further demonstrate that though Akt signaling in response to insulin is intact, insulin-induced translocation of GLUT1 occurs independently of Akt activation in LβT2 cells.

BACKGROUND: Interleukin-18 (IL-18), or interferon (IFN)-γ-inducing factor, potentiates T helper 1 and natural killer cell activation as well as CD8+ T-cell proliferation. Recombinant IL-18 has displayed limited clinical efficacy in part due to the expression of the decoy receptor, IL-18 binding protein (IL-18BP). A series of IL-18 variants that are devoid of IL-18BP binding, termed DR18 (decoy-resistant IL-18), was developed via directed evolution. We tested DR18 using oncolytic adenovirus (oAd) as a platform for delivery in syngeneic mouse tumor models. METHODS: oAd harboring wild-type IL-18 or DR18 (oAdDR18) was constructed by inserting IL-18 mutant into modified oAd backbone with Ad5/3 chimeric fiber. The delivery effect and IFN-γ induction were determined by ELISA. The antitumor efficiency of oAdDR18 was tested in CT26, B16BL6 and 4T1 tumor-bearing mice, or athymic nude mice and compared with recombinant DR18 protein (rDR18). 4T1 lung metastasis model was used to evaluate the antitumor efficiency of local and distant tumors. Antitumor memory and synergistic effect with an anti-programmed cell death protein-1 (PD-1) antibody was evaluated. The phenotypes of the immune cells in tumor microenvironment were analyzed by flow cytometry and immunohistochemistry. RESULTS: Mice received oAdDR18 maintained stable production of IL-18 and IFN-γ compared with those received rDR18. Intratumoral delivery of oAdDR18 significantly reduced tumor growth across several tumor models, but not in the athymic nude mouse model. Mice that had tumor remission showed antitumor memory. The antitumor effect was associated with intratumor infiltration of CD4+ and CD8+ T cells. DR18 delivered by oAd demonstrated long-lasting and enhanced antitumor activities against local and distant tumors compared with that received rDR18 or wild-type IL-18 delivered by oAd (oAdwtIL-18). oAdDR18 treatment also reduced 4T1 lung metastasis. In addition, combination of this virotherapy with immune checkpoint inhibitors (ICIs)like the anti-PD-1 antibody further enhanced the antitumor activity as compared with respective monotherapy. CONCLUSIONS: oAdDR18 demonstrates enhanced antitumor activities through the induction of stronger local and system immunities and modulation of the tumor microenvironment compared with those of oAdwtIL-18 and rDR18. A combination of oncolytic virotherapy with cytokine engineering would lead to cytokine-based therapeutics for cancer and other diseases.

PURPOSE: Patients with invasive lobular carcinoma (ILC) face high rates of positive margins and completion mastectomy, which can be improved with the use of specific techniques, such as oncoplastic surgery. However, prior studies have shown that type of breast cancer surgery performed is also associated with patient factors such as elevated body mass index (BMI). Thus, this study investigates whether BMI impacts the type of surgical interventions in patients with ILC. METHODS: A retrospective analysis of 705 patients with stage I-III ILC from an institutional database was conducted. Patients were stratified by BMI (underweight, normal weight, overweight, obese). Pearsons Chi-square, ANOVA, and multivariable logistic regression were used to evaluate the relationship between BMI and surgical procedures. RESULTS: Breast-conserving surgery (BCS) was the initial operation in 60% of patients, with no significant difference by BMI. Among those undergoing BCS, patients with obese BMI were significantly more likely to undergo oncoplastic surgery (46.9% vs. 7.7%, 37.3%, and 33.6% for underweight, normal, and overweight, respectively, p = 0.032). Obese BMI patients undergoing mastectomy were less likely to have reconstruction compared to those with underweight, normal weight, and overweight BMI (44.2% vs. 50%, 71.1%, and 64.1%, p = 0.002). CONCLUSION: Overweight/obese BMI patients with ILC underwent different surgical interventions compared to those with lower BMI. While initial BCS rates were similar, overweight/obese patients had higher oncoplastic surgery rates in BCS and lower reconstruction rates in mastectomy. Further research is needed to understand BMIs impact on surgical decisions and outcomes in ILC.

Significance

BACKGROUND: Historically, the clinical characteristics and treatment pathways for patients with uterine fibroids and heavy menstrual bleeding have differed between White and Black women. OBJECTIVE: To provide a contemporary comparison of patient characteristics and treatment patterns among White and Black women with uterine fibroids and heavy menstrual bleeding in the United States. STUDY DESIGN: This retrospective cohort study included administrative claims data from 46,139 White and 17,297 Black women with uterine fibroids and heavy menstrual bleeding from the Optum Clinformatics database (January 2011-December 2020) and 7353 White and 16,776 Black women from the IBM MarketScan Multi-State Medicaid Insurance database (January 2010-December 2019). Patients were indexed at their initial uterine fibroid diagnosis claim and were required to have a claim for heavy menstrual bleeding and ≥12 months of continuous enrollment pre- and postindex. Patients were followed until the earliest of death, disenrollment, hysterectomy date, or end of study database. Outcomes were stratified by race and included patient demographics, clinical characteristics, pharmacologic treatment patterns, and surgeries/procedures. Pearsons Chi-square test for categorical variables and Students t-test for continuous data were used to evaluate differences in baseline characteristics. Descriptive statistics were used to characterize treatment pathways for hormonal contraceptive use in women with ≥24 months of follow-up. Kaplan-Meier survival analysis was used to estimate time until hysterectomy, with log-rank testing to assess between-group differences. RESULTS: The mean (standard deviation) duration of follow-up was 44.6 (27.9) and 41.0 (24.9) months in the commercial and Medicaid databases, respectively. Mean (standard deviation) age at uterine fibroid diagnosis was lower for Black than White women in both databases (commercial: 42.3 [6.5] vs 44.4 [6.3] years; P<.0001; Medicaid: 39.6 [7.1] years vs 40.2 [7.2] years; P<.0001). Anemia was more prevalent in Black vs White women in both databases (commercial: 5.9% [1028/17,297] vs 3.6% [1648/46,139]; P<.0001; Medicaid: 7.0% [1180/16,776] vs 4.5% [331/7353]; P<.0001). In the commercial database, approximately one-half of women had claims for ≥1 bulk symptom, with no significant differences between groups. In the Medicaid database, significantly more White than Black women had claims for bulk symptoms (77.0% [5665/7353] vs 68.4% [11,477/16,776]; P<.0001). Approximately 40% of all patients received hormonal drug therapies as initial treatment, most commonly hormonal contraceptives. However, discontinuation of hormonal contraceptive therapy was nearly universal, with one-half discontinuing within a median treatment duration of ∼5 months. Most women stopped treatment after 1 or 2 agents (commercial: White, 89.9% [9757/10,857]; Black, 90.0% [3594/3993]; Medicaid: White, 92.2% [1635/1773]; Black, 94.2% [4454/4726]). Hysterectomy was the most common procedure, and was more common among White vs Black women (commercial: 43.9% [20,235/46,139] vs 37.8% [6536/17,297]; Medicaid: 46.8% [3444/7353] vs 32.0% [5364/16,776]). CONCLUSIONS: Black women with UF-HMB were diagnosed at a younger age than White women, and White women had higher hysterectomy rates than Black women, representing a shift from earlier researched treatment patterns. Patients with UF-HMB were also highly reliant on hormonal contraceptives, followed by nearly universal therapeutic discontinuation.

Wildlife biodiversity is essential for healthy, resilient and sustainable ecosystems. For biologists, this diversity also represents a treasure trove of genetic, molecular and developmental mechanisms that deepen our understanding of the origins and rules of life. However, the rapid decline in biodiversity reported recently foreshadows a potentially catastrophic collapse of many important ecosystems and the associated irreversible loss of many forms of life on our planet. Immediate action by conservationists of all stripes is required to avert this disaster. In this Spotlight, we draw together insights and proposals discussed at a recent workshop hosted by Revive & Restore, which gathered experts to discuss how stem cell technologies can support traditional conservation techniques and help protect animal biodiversity. We discuss reprogramming, in vitro gametogenesis, disease modelling and embryo modelling, and we highlight the prospects for leveraging stem cell technologies beyond mammalian species.

Puberty is the critical developmental transition to reproductive capability driven by the activation of gonadotropin-releasing hormone (GnRH) neurons. The complex neural mechanisms underlying pubertal activation of GnRH secretion still remain unknown, yet likely include kisspeptin neurons. However, kisspeptin neurons reside in several hypothalamic areas and the specific kisspeptin population timing pubertal onset remains undetermined. To investigate this, we strategically capitalized on the differential ontological expression of the Kiss1 gene in different hypothalamic nuclei to selectively ablate just arcuate kisspeptin neurons (aka KNDy neurons) during the early juvenile period, well before puberty, while sparing RP3V kisspeptin neurons. Both male and female transgenic mice with a majority of their KNDy neurons ablated (KNDy^ABL) by diphtheria toxin treatment in juvenile life demonstrated significantly delayed puberty onset and lower peripubertal LH secretion than controls. In adulthood, KNDy^ABL mice demonstrated normal in vivo LH pulse frequency with lower basal and peak LH levels, suggesting that only a small subset of KNDy neurons is sufficient for normal GnRH pulse timing but more KNDy cells are needed to secrete normal LH concentrations. Unlike prior KNDy ablation studies in rats, there was no alteration in the occurrence or magnitude of estradiol-induced LH surges in KNDy^ABL female mice, indicating that a complete KNDy neuronal population is not essential for normal LH surge generation. This study teases apart the contributions of different kisspeptin neural populations to the control of puberty onset, demonstrating that a majority of KNDy neurons in the arcuate nucleus are necessary for the proper timing of puberty in both sexes.

INTRODUCTION: Reducing cardiopulmonary bypass (CPB) induced inflammatory injury is a potentially important strategy for children undergoing multiple operations for single ventricle palliation. We sought to characterize the soluble receptor for advanced glycation end products (sRAGE), a protein involved in acute lung injury and inflammation, in pediatric patients with congenital heart disease and hypothesized that patients undergoing single ventricle palliation would have higher levels of sRAGE following bypass than those with biventricular physiologies. METHODS: This was a prospective, observational study of children undergoing CPB. Plasma samples were obtained before and after bypass. sRAGE levels were measured and compared between those with biventricular and single ventricle heart disease using descriptive statistics and multivariate analysis for risk factors for lung injury. RESULTS: sRAGE levels were measured in 40 patients: 19 with biventricular and 21 with single ventricle heart disease. Children undergoing single ventricle palliation had a higher factor and percent increase in sRAGE levels when compared to patients with biventricular circulations (4.6 vs. 2.4, p = 0.002) and (364% vs. 181%, p = 0.014). The factor increase in sRAGE inversely correlated with the patients preoperative oxygen saturation (Pearson correlation (r) = -0.43, p = 0.005) and was positively associated with red blood cell transfusion (coefficient = 0.011; 95% CI: 0.004, 0.017; p = 0.001). CONCLUSIONS: Children with single ventricle physiology have greater increase in sRAGE following CPB as compared to children undergoing biventricular repair. Larger studies delineating the role of sRAGE in children undergoing single ventricle palliation may be beneficial in understanding how to prevent complications in this high-risk population.

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