👤 Anne E Carpenter

Sleep is a marker of brain function that could potentially identify patients for early intervention by detecting cognitive change during the early asymptomatic stages of Alzheimer disease (AD). We examined the relationship between sleep and cognition in cognitively unimpaired older adults and evaluated whether the relationship was altered by AD risk factors. Cognitively unimpaired older adults (N = 319, age 54-97 years) were administered a sleep diary (1x/day) and brief cognitive assessments (4x/day) for seven consecutive days via a smartphone application. We evaluated if a previous night's sleep predicts next-day cognition and if sleep averaged over a week predicts cognitive performance averaged over a week. Additional analyses included the effects of carrying an apolipoprotein (APOE) ε4 allele and cerebrospinal fluid biomarkers of AD pathology. At the between-person level, no associations were observed between sleep and cognition. Within-person analyses revealed that deviations (both higher and lower scores) from an individual's usual sleep pattern were associated poorer next day cognitive performance. Carriage of the APOE ε4 allele and AD biomarkers did not interact with sleep-cognition relationships. Remote, multi-day assessments of cognition and sleep revealed subtle non-linear associations between nightly sleep and next-day cognition in cognitively unimpaired older adults. Furthermore, the individualized nature of sleep-cognition relationships underscores the importance of maintaining consistent person-centered sleep health metrics to support cognitive function. Capturing latent AD-related changes in sleep and cognition among asymptomatic older adults may require repeated assessments across extended timeframes. Show less

Uterine fibroids, or leiomyomas, are noncancerous tumors of the myometrium and the most common tumors in women, with a cumulative incidence of approximately 80% by age 50. Currently, hysterectomy is the only definitive cure, and effective non-hormonal therapeutics are lacking. Understanding the etiology of fibroids may lead to alternative, less invasive treatments. Several obstetric disorders, including polycystic ovary syndrome (PCOS), have been linked to uterine fibroids, and women with PCOS often exhibit hormonal imbalances, particularly elevated serum testosterone levels. However, the impact of testosterone on the myometrium remains poorly understood. We hypothesize that elevated testosterone may increase the risk of developing uterine fibroids. Using RNA sequencing and MethylationEPIC array analyses, we compared myometrial tissue from women without fibroids (MyoN, n = 33), with fibroids (MyoF, n = 66), and after testosterone therapy as part of clinical care for gender dysphoria (MyoT, n = 7). The transcriptomic and methylation profiles of MyoT clustered with MyoF and were distinct from MyoN. We identified 1,321 differentially expressed protein-coding genes between MyoT and MyoN, while only 494 were found between MyoT and MyoF. Disease ontology analysis of MyoT vs. MyoN revealed enrichment of the fibroid tumor gene set. Fibroid associated genes including TGFβ3, CCND1, SERPINE1, and FGFR1 were upregulated in MyoT and MyoF samples compared to MyoN samples. The DNA methylation profiles of MyoT were closer to those of MyoF, but no correlation was observed between methylation status and gene expression. Our preliminary data suggest that exogenous testosterone induces transcriptional and methylation changes in the myometrium consistent with those observed in MyoF tissues. These findings suggest that elevated testosterone may be associated with an increased risk of developing uterine fibroids. Show less

Phosphaturic mesenchymal tumors (PMT) are uncommon neoplasms that cause hypophosphatemia/osteomalacia mainly by secreting fibroblast growth factor 23. We previously identified FN1::FGFR1/FGF1 fusions in nearly half of the PMTs and frequent KL (Klotho or α-Klotho) overexpression in only those with no known fusion. Here, we studied a larger cohort of PMTs for KL expression and alterations. By FN1 break-apart fluorescence in situ hybridization (FISH) and reappraisal of previous RNA sequencing data, 6 tumors previously considered "fusion-negative" (defined by negative results of FISH for FN1::FGFR1 fusion and FGF1 break-apart and/or of RNA sequencing) were reclassified as fusion-positive PMTs, including 1 containing a novel FN1::ZACN fusion. The final cohort of fusion-negative PMTs included 33 tumors from 32 patients, which occurred in the bone (n = 18), soft tissue (n = 10), sinonasal tract (n = 4), and brain (n = 1). In combination with previous work, RNA sequencing, RNA in situ hybridization, and immunohistochemistry showed largely concordant results and demonstrated KL/α-Klotho overexpression in 17 of the 28 fusion-negative and none of the 10 fusion-positive PMTs studied. Prompted by a patient in this cohort harboring germline KL upstream translocation with systemic α-Klotho overexpression and multifocal PMTs, FISH was performed and revealed KL rearrangement in 16 of the 33 fusion-negative PMTs (one also with amplification), including 14 of the 17 cases with KL/α-Klotho overexpression and none of the 11 KL/α-Klotho-low fusion-negative and 11 fusion-positive cases studied. Whole genomic sequencing confirmed translocation and inversion in 2 FISH-positive cases involving the KL upstream region, warranting further investigation into the mechanism whereby these rearrangements may lead to KL upregulation. Methylated DNA immunoprecipitation and sequencing suggested no major role of promoter methylation in KL regulation in PMT. Interestingly, KL-high/-rearranged cases seemed to form a clinicopathologically homogeneous group, showing a predilection for skeletal/sinonasal locations and typically matrix-poor, cellular solitary fibrous tumor-like morphology. Importantly, FGFR1 signaling pathways were upregulated in fusion-negative PMTs regardless of the KL status compared with non-PMT mesenchymal tumors by gene set enrichment analysis, perhaps justifying FGFR1 inhibition in treating this subset of PMTs. Show less

SignificanceTirzepatide is a dual agonist of the glucose-dependent insulinotropic polypeptide receptor (GIPR) and the glucagon-like peptide-1 receptor (GLP-1R), which are incretin receptors that regulate carbohydrate metabolism. This investigational agent has proven superior to selective GLP-1R agonists in clinical trials in subjects with type 2 diabetes mellitus. Intriguingly, although tirzepatide closely resembles native GIP in how it activates the GIPR, it differs markedly from GLP-1 in its activation of the GLP-1R, resulting in less agonist-induced receptor desensitization. We report how cryogenic electron microscopy and molecular dynamics simulations inform the structural basis for the unique pharmacology of tirzepatide. These studies reveal the extent to which fatty acid modification, combined with amino acid sequence, determines the mode of action of a multireceptor agonist. Show less

In this work, we describe the use of the rule of 3 fragment-based strategies from biochemical screening data of 1100 in-house, small, low molecular weight fragments. The sequential combination of in silico fragment hopping and fragment linking based on S160/Y161/A162 hinge residues hydrogen bonding interactions leads to the identification of novel 1H-benzo[d]imidazol-2-yl)-1H-indazol class of Phosphoinositide-Dependent Kinase-1 (PDK1) inhibitors. Consequent SAR and follow-up screening data led to the discovery of two potent PDK1 inhibitors: compound 32 and 35, with an IC Show less

Changes in chromatin structure are a key aspect in the epigenetic regulation of gene expression. We have used a lac operator array system to visualize by light microscopy the effect of heterochromatin protein 1 (HP1) alpha (HP1alpha) and HP1beta on large-scale chromatin structure in living mammalian cells. The structure of HP1, containing a chromodomain, a chromoshadow domain, and a hinge domain, allows it to bind to a variety of proteins. In vivo targeting of an enhanced green fluorescent protein-tagged HP1-lac repressor fusion to a lac operator-containing, gene-amplified chromosome region causes local condensation of the higher-order chromatin structure, recruitment of the histone methyltransferase SETDB1, and enhanced trimethylation of histone H3 lysine 9. Polycomb group proteins of both the HPC/HPH and the EED/EZH2 complexes, which are involved in the heritable repression of gene activity, are not recruited to the amplified chromosome region by HP1alpha and HP1beta in vivo targeting. HP1alpha targeting causes the recruitment of endogenous HP1beta to the chromatin region and vice versa, indicating a direct interaction between the two HP1 homologous proteins. Our findings indicate that HP1alpha and HP1beta targeting is sufficient to induce heterochromatin formation. Show less