RESUMEN
Genetic manipulation of animal models is a fundamental research tool in biology and medicine but is challenging in large animals. In rodents, models can be readily developed by knocking out genes in embryonic stem cells or by knocking down genes through in vivo delivery of nucleic acids. Swine are a preferred animal model for studying the cardiovascular and immune systems, but there are limited strategies for genetic manipulation. Lipid nanoparticles (LNPs) efficiently deliver small interfering RNA (siRNA) to knock down circulating proteins, but swine are sensitive to LNP-induced complement activation-related pseudoallergy (CARPA). We hypothesized that appropriately administering optimized siRNA-LNPs could knock down circulating levels of plasminogen, a blood protein synthesized in the liver. siRNA-LNPs against plasminogen (siPLG) reduced plasma plasminogen protein and hepatic plasminogen mRNA levels to below 5% of baseline values. Functional assays showed that reducing plasminogen levels modulated systemic blood coagulation. Clinical signs of CARPA were not observed, and occasional mild and transient hepatotoxicity was present in siPLG-treated animals at 5 h post-infusion, which returned to baseline by 7 days. These findings advance siRNA-LNPs in swine models, enabling genetic engineering of blood and hepatic proteins, which can likely expand to proteins in other tissues in the future.
RESUMEN
Context: Current Endocrine Society guidelines recommend that transgender women taking spironolactone have their potassium levels checked every 3 months for the first year after initiating therapy and annually thereafter to monitor for hyperkalemia. Objective: The goal of this study was to assess the need for such frequent potassium monitoring and to investigate whether age plays a role in potassium abnormalities in transgender, gender diverse, and nonbinary (TGDNB) individuals taking spironolactone. Methods: Using EPIC-Clarity, a retrospective study of healthy, adult individuals with gender-identity disorder listed in their problem list and taking spironolactone was performed. We analyzed the incidence of hyperkalemia in this population. Data from June 2006 through November 2021 were obtained. Exclusion criteria included hypertension, renal failure, diabetes mellitus, heart failure, and medications that affect the renin-angiotensin-aldosterone system. Results: 318 healthy TGDNB individuals met our inclusion criteria. We identified 8/318 (2.5%) individuals with hyperkalemia on spironolactone. There was a significant difference in incidence of hyperkalemia events in those >45 years old and those ≤45 years old (8.9% vs 1.5%, P = .016). Conclusion: Our data suggest the incidence of hyperkalemia in our TGDNB population is low, particularly in those ≤45 years old; however, this risk increases with age. These findings suggest practice guidelines may need to be adjusted to minimize unnecessary testing in the population ≤45 years old who are not plagued by comorbidities that affect potassium handling.
RESUMEN
Synthetic methodology utilizing two aryne intermediates (i.e., a formal benzdiyne) enables the rapid generation of structurally complex molecules with diverse functionality. This report describes the sequential generation of two ortho-benzyne intermediates for the synthesis of 2,3-disubstituted aryl phosphonates. Aryl phosphonates have proven useful in medicinal chemistry and materials science, and the reported methodology provides a two-step route to functionally dense variants by way of 3-phosphonyl benzyne intermediates. The process begins with regioselective trapping of a 3-trifloxybenzyne intermediate by an O-silyl phosphite in an Abramov-like reaction to bond the strained Csp carbons with phosphorus and silicon. Standard aryne-generating conditions follow to convert the resulting 2-silylphenyl triflate into a 3-phosphonyl benzyne, which readily reacts with numerous aryne trapping reactants to form a variety of 2,3-difunctionalized aryl phosphonate products. DFT computational studies shed light on important mechanistic details and revealed that 3-phosphonyl benzynes are highly polarizable. Specifically, the distortion in the internal bond angles at each of the Csp atoms was strongly influenced by both the electronegativity of the phosphonate ester groups as well as the dielectric of the computational solvation model. These effects were verified experimentally as the regioselectivity of benzyl azide trapping increased with more electronegative esters and/or increasingly polar solvents. Conversely, replacing the conventional solvent, acetonitrile, with nonpolar alternatives provided attenuated or even inverted selectivities. Overall, these studies showcase new reactivity of benzyne intermediates and extend the aryne relay methodology to include organophosphonates. Furthermore, this work demonstrates that the regioselectivity of aryne trapping reactions could be tuned by simply changing the solvent.
