Faculty Bibliography

Trypanosomatids are parasites of health importance that cause neglected diseases in humans and animals. Chagas' disease, caused by Trypanosoma cruzi, affects 6-7 millions of people worldwide, mostly in Latin America, most of whom do not have access to diagnosis or treatment. Currently, there are no available vaccines, and the antiparasitic drugs used for treatment are often toxic and ineffective for the chronic stage of infection. Therefore, exploration of new therapeutic targets is necessary and highlights the importance of identifying new therapeutic options for the treatment of this disease. Trypanosomatid genes are organized and expressed in a species-specific fashion and many of their regulatory factors remain to be explored, so proteins involved in the regulation of gene expression are interesting candidates as drug targets. Previously, we demonstrated that the TbRRM1 protein from T. brucei is an essential nuclear factor involved in Pol-II transcriptional regulation. TcSR62 is a TbRRM1 orthologous protein in T. cruzi, but little is known about its function. In this study, we used molecular modeling of the RNA-binding domains of the TcSR62 protein and computational molecular docking to identify TcSR62-specific drug candidates. We identified sorafenib tosylate (ST) as a compound with trypanocidal activity. Sorafenib tosylate showed promising half-maximal inhibitory concentration (IC50) for all parasite stages in vitro. Furthermore, overexpression of TcSR62 protein led to ST-resistant parasites, suggesting that the trypanocidal effect might be due to the inhibition of TcSR62 function. These results demonstrate that ST could be repurposed as a novel drug to treat Chagas' disease.

The oral mucosal calcified nodule (OMCN) is a rare soft tissue lesion with only 7 cases reported in the English literature. It typically presents in the pediatric population as an asymptomatic submucosal nodule of less than 2 cm size affecting the maxillary ridge or palate, though other sites are reported. The histopathology displays stratified squamous epithelium overlying fibrous connective tissue with embedded calcified aggregates bordered by variable numbers of multinucleated giant cells. Surgical excision is curative. In this report, we present a new case of OMCN, outline the characteristic histopathologic features and review the cases reported in the English literature.

Progressive supranuclear palsy (PSP) is a rare, debilitating neurodegenerative disorder that significantly impairs both motor and cognitive functions. Current pharmacological treatments offer only transient symptomatic relief, driving interest in the past in alternative therapeutic strategies such as deep brain stimulation. Deep brain stimulation (DBS), known for its success in treating motor symptoms of Parkinson's disease, has been explored as a possible symptomatic treatment for PSP, considering the pedunculopontine nucleus (PPN), involved in motor control and postural stability, as a promising target for deep brain stimulation in PSP. However, its complex anatomy and the clinical variability of PSP complicate the prediction and generalization of the effectiveness of DBS. The present review examines the existing studies in the literature about DBS in PSP patients. Some studies highlighted modest benefits in motor symptoms, while others reported variable outcomes and inherent risks of the procedure. Generally, patients with a parkinsonism predominant phenotype have shown some subjective or clinical improvements in gait and balance when subjected to low-frequency stimulation. While DBS of the PPN holds promise for ameliorating gait and balance of PSP, current evidence does not yet establish clear criteria for ideal candidates, nor does it provide overwhelmingly supportive results in favor of PPN-DBS in PSP patients. Without any further systematic study is not possible to define accurate candidate selection parameters and understand long-term outcomes and safety profiles.

Natural gene variants of metabotropic glutamate receptor subtype 7 (Grm7), coding for mGluR7, affect individuals' alcohol-drinking preference. Psychopharmacological investigations have suggested that mGluR7 is also involved in responses to cocaine, morphine, and nicotine exposures. We review the pleiotropic effects of Grm7 and the principle of recombinant quantitative trait locus introgression (RQI), which led to the discovery of the first mammalian quantitative gene accounting for alcohol-drinking preference. Grm7/GRM7 can play important roles in mammalian ontogenesis, brain development, and predisposition to addiction. It is also involved in other behavioral phenotypes, including emotion, stress, motivated cognition, defensive behavior, and pain-related symptoms. This review identified pleiotropy and the modulation of neurobehavioral processes by variations in the gene Grm7/GRM7. Patterns of pleiotropic genes can form oligogenic architectures whosecombined additive and interaction effects can significantly predispose individuals to the expressions of disorders. Identifying and characterizing pleiotropic genes are necessary for understanding the expressions of complex traits. This requires tasks, such as discovering and identifying novel genetic elements of the genetic architecture, which are unsuitable for AI but require classical experimental genetics.

Although platelets play a critical pathogenic role in myocardial infarction (MI), few studies have characterized the MI platelet transcriptome in the acute or chronic setting in women. We report that transcripts associated with the actin cytoskeleton, Rho family GTPases, mitochondrial dysfunction, and inflammatory signaling are enriched in platelets from MI patients in the acute setting (n = 40, MI; n = 38, control) and do not significantly change over time. Furthermore, 79 platelet genes chronically elevated or suppressed after MI are associated with future cardiovascular events in an independent high-risk cohort (n = 135). Compared with women with MI with nonobstructive coronary arteries, platelets from women with MI and obstructive coronary artery disease were enriched in neutrophil activation and proinflammatory signaling pathways driven by increased tumor necrosis factor (TNF)-α signaling. Hierarchic clustering of the MI transcriptomic profile identified 3 subgroups with distinctive biological pathways and MI correlates. Our data demonstrate that platelets from MI patients are phenotypically different from MI-naïve patients in the acute and chronic settings and reveal a platelet transcriptomic signature with distinct clinical features.

INTRODUCTION/BACKGROUND:Disturbances in microvascular flow dynamics are hypothesized to precede the symptomatic phase of Alzheimer's disease (AD). However, evidence in presymptomatic AD remains elusive, underscoring the need for therapies targeting these early vascular changes. METHODS:We employed a multimodal approach, combining in vivo optical imaging, molecular techniques, and ex vivo magnetic resonance imaging, to investigate early capillary dysfunction in C57BL/6-Tg(Thy1-APPSwDutIowa)BWevn/Mmjax (Tg-SwDI) mice without memory impairment. We also assessed the efficacy of carbonic anhydrase inhibitors (CAIs) in preventing capillary flow disturbances. RESULTS:Our study revealed capillary flow disturbances associated with alterations in capillary morphology, adhesion molecule expression, and amyloid beta (Aβ) load in 9- to 10-month-old Tg-SwDI mice without memory impairment. CAI treatment ameliorated these capillary flow disturbances, enhanced oxygen availability, and reduced Aβ load. DISCUSSION/CONCLUSIONS:These findings underscore the importance of capillary flow disturbances as early biomarkers in presymptomatic AD and highlight the potential of CAIs for preserving vascular integrity in the early stages of AD. HIGHLIGHTS/CONCLUSIONS:Uncovered early capillary dysfunction in a presymptomatic Alzheimer's disease (AD) mouse model. Evidence linking capillary stalls and capillary dysfunction with oxygen delivery issues in AD. Novel use of carbonic anhydrase inhibitors to prevent early capillary flow disturbances in AD.

PURPOSE OF REVIEW/OBJECTIVE:Chylomicron biosynthesis plays a vital role in supplying essential lipids and lipid soluble vitamins to peripheral tissues for various functions. Despite this, the intracellular synthesis, trafficking, and secretion of chylomicrons remains only partly understood. The purpose of this review is to summarize the role of established proteins in this process and bring attention to recently identified proteins to provide an up-to-date model of chylomicron biosynthesis. RECENT FINDINGS/RESULTS:Recently, several proteins have been shown to play a role in the initial formation and lipidation of chylomicrons at the endoplasmic reticulum (ER), which include: TM6SF2, PLA2G12B, PRAP1, and SURF4. In addition, mitochondria have been implicated in chylomicron metabolism, but mechanistic insight is missing. The trafficking of chylomicrons from the ER to the Golgi, and the subsequent trafficking from the Golgi to the basolateral side of enterocytes, however, remains a mystery. SUMMARY/CONCLUSIONS:Progress in the chylomicron biosynthesis field is largely associated with findings in VLDL biosynthesis. In addition, increased insight in events after prechylomicrons leave the ER is needed. Given the important role of chylomicron biosynthesis in whole-body lipid metabolism, further research into the molecular mechanisms is warranted.

BACKGROUND/UNASSIGNED:Whether prolonged and excessive alcohol consumption contributes to dilated cardiomyopathy (DCM) remains uncertain. This study aimed to describe the prevalence of alcohol use in patients with DCM and their first-degree relatives (FDRs) and determine if cumulative alcohol exposure associates with DCM/partial DCM or modifies the association of DCM with DCM-relevant rare variants. METHODS/UNASSIGNED:All probands had DCM; FDRs were classified as with or without DCM or partial DCM. Alcohol exposure was measured with the Alcohol Use Disorder Identification Test-Consumption questionnaire and years of drinking. Rare variants in 36 DCM genes were classified as pathogenic, likely pathogenic, or variants of uncertain significance (pathogenic, likely pathogenic, variant of uncertain significance). Generalized linear mixed models were used to assess the association of DCM/partial DCM with alcohol use among FDRs. RESULTS/UNASSIGNED:=0.55). CONCLUSIONS/UNASSIGNED:Alcohol use was frequent among probands and FDRs. This study did not provide evidence supporting an association of cumulative alcohol exposure with DCM/partial DCM or a modifying effect of alcohol use on the association of DCM with DCM-relevant rare variants. REGISTRATION/UNASSIGNED:URL: https://www.clinicaltrials.gov; Unique identifier: NCT03037632.

BACKGROUND:Four-dimensional computed tomography is routinely used to localize parathyroid disease, with consistently excellent parathyroid gland localization rates reported. This study evaluated whether pairing 4-dimensional computed tomography results with preoperative clinical variables can accurately predict single-gland disease in primary hyperparathyroidism. METHODS:Patients with primary hyperparathyroidism who underwent both 4-dimensional computed tomography imaging and parathyroidectomy between January 2019 and September 2021 at a large academic health system were included. Patient demographics, preoperative characteristics, and peri- and postoperative data were collected. The accuracy of 4-dimensional computed tomography in correctly identifying patients with single-gland disease with and without preoperative calcium and parathyroid hormone levels was calculated. Single-gland disease was defined by intraoperative parathyroid hormone decrease >50% and a hypercellular gland on pathology. RESULTS:One hundred seventy-five patients had 4-dimensional computed tomography results suggestive of single gland disease. One hundred fifty-two patients (87%) were predicted correctly to have single-gland disease. The predictive accuracy increased when stratifying by preoperative calcium (≥10.5 mg/dL, ≥11 mg/dL, and ≥12 mg/dL) and parathyroid hormone levels (≥65 pg/mL, ≥100 pg/mL, and ≥200 pg/dL). The accuracy further increased when stratifying by age (≤50 years). Accuracy for single gland disease was 100% when combined with any of the following: (1) calcium ≥12 mg/dL, (2) parathyroid hormone ≥200 pg/dL, or (3) calcium ≥11 mg/dL in patients ≤50 years. CONCLUSION/CONCLUSIONS:Four-dimensional computed tomography alone accurately predicted single gland disease in 87% of patients with primary hyperparathyroidism. When combined with preoperative calcium, parathyroid hormone and age thresholds, predictive accuracy for single-gland disease approached 100%. Given the high likelihood of single-gland disease in these scenarios, clinicians may consider offering focused unilateral parathyroidectomy without intraoperative parathyroid hormone monitoring in selected patients.