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Biology subjects

Alakesh, A.

Publications and source records attributed to Alakesh, A..

5 recordsLinked to original sources

Structure-Property-Performance Engineering of Hydrogel Depots for Long-Acting Peptide Delivery

Controlled release systems for subcutaneous peptide delivery often exhibit a pronounced initial burst release followed by inadequate maintenance of therapeutic exposure, limiting depot lifetime and increasing pharmacokinetic variability. Here, we engineer a dynamic, injectable hydrogel depot technology for months-long delivery of lipidated peptides. Using semaglutide as a model, we establish a modular formulation framework integrating: (i) formulation-driven tuning of depot mechanics to control release kinetics, (ii) cargo complexation strategies leveraging hydrophobic and multivalent ion-mediated interactions, and (iii) oxidative stabilization through sacrificial antioxidant excipients. We evaluated depot performance by rheology, in vitro cargo release, and in vivo pharmacokinetic and pharmacodynamic studies in rodents. Optimized formulations sustained semaglutide exposure for over six weeks from a single administration with two-fold reduction in peak-to-trough exposure and comparable total bioavailability relative to daily dosing, resulting in improved glucose control, weight regulation, and preservation of pancreatic islet content. These results suggest potential for quarterly dosing in humans. Together, this work establishes integrated and generalizable structure-property-performance relationships that account for cargo-matrix and cargo-excipient interactions across burst, diffusion, and erosion regimes to inform a practical formulation framework for engineering long-acting depots for sustained peptide delivery.

bioengineering↗

Intranasal sertraline for the investigation of nose-to-brain delivery to mitigate systemic exposure

Antenatal depression, or depression during pregnancy, is a common psychiatric disorder and poses significant risks to both the mother and the fetus. Despite these risks, it is frequently left untreated due to fears of side effects caused by antidepressant medications which cross through the placental barrier. It is therefore desirable to develop formulation strategies to mitigate systemic exposure to relevant drug molecules while maintaining their psychotropic efficacy. In this work, we develop formulations of sertraline, a common antidepressant, to target delivery to the brain through intranasal administration. Formulation engineering enables successful solubilization of sertraline at high concentrations and our lead formulation remains stable at room temperature for months. Using mice, we compare sertraline biodistribution following intranasal administration and standard oral administration. Intranasal administration of our drug product candidate provides comparable brain exposure at half the dose compared to oral treatment and lowers the maximum plasma exposure. These findings suggest that intranasal administration may provide selectivity for drug exposure in the central nervous system over systemic exposure.

pharmacology and toxicology↗

Long-acting hydrogel-based depot formulations of tirzepatide and semaglutide for the management of type 2 diabetes and weight

Several incretin hormone therapies have been clinically approved and have revolutionized the treatment of diabetes and obesity. Promising therapeutics include semaglutide (Ozempic(R) and Wegovy(R)), an agonist for glucagon-like peptide-1 (GLP-1) receptor, and tirzepatide (Mounjaro(R)), a dual agonist for GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) receptors. These molecules help to regulate blood glucose levels, enhance insulin secretion and sensitivity, and reduce appetite. Currently, these treatments require weekly injections, which can be challenging for patients to adhere to. We recently reported the development of an injectable hydrogel depot technology enabling months-long release of semaglutide (Sema). Here, we further develop this technology for improved prolonged release of both Sema and tirzepatide (TZP). In a rat model of diabetes, we show a single administration of hydrogel-based formulations of either Sema or TZP maintained relevant drug levels for over 6 weeks. In these studies, single administrations of long-acting hydrogel-based therapies of Sema or TZP were similarly effective at regulating blood glucose and weight compared to daily injections of either Sema or TZP in standard aqueous vehicles. This hydrogel depot technology is easy to manufacture, injectable, and exhibits excellent biocompatibility, enabling months-long-acting treatments with the potential to improve management of diabetes and weight.

bioengineering↗

Chronic Inflammation Induced Immature Neutrophils Drive Immunopathology During Subsequent Inflammatory Events

Individuals with underlying chronic inflammatory conditions are prone to increased morbidity when posed with an additional inflammatory challenge such as an injury or infection, but why this occurs remains unclear. Herein, we address this question in mouse models by demonstrating that chronic inflammation results in a pronounced expansion of circulating immature neutrophils that exhibit dysregulated effector functions as determined by single cell RNA sequencing and ex vivo functional assays. We show that these immature neutrophils are associated with and contribute to increased immunopathology in response to a new inflammatory challenge. Blocking the migration or function of these immature neutrophils through the administration of therapeutic antibodies or small molecules, profoundly lowers the immunopathology caused by the inflammatory challenge. Together, these studies establish a causal link between immature neutrophils and increased immunopathology, while also providing insights into new therapeutic strategies for treating individuals with chronic inflammatory ailments.

immunology↗

Particle Uptake Driven Phagocytosis in Macrophages and Neutrophils Enhances Bacterial Clearance

Humans are exposed to numerous synthetic foreign particulates in the form of environmental pollutants and diagnostic or therapeutic agents. Specialized immune cells (phagocytes) clear these particulates by phagocytosing and attempting to degrade them. The process of recognition and internalization of the particulates may trigger changes in the function of phagocytes. Some of these changes, especially the ability of a particle-loaded phagocyte to take up and neutralize pathogens, remains poorly studied. Herein, we demonstrate that the uptake of non-stimulatory cargo-free particles enhances the phagocytic ability of monocytes, macrophages and neutrophils. The enhancement in phagocytic ability was independent of particle properties, such as size or the base material constituting the particle. Additionally, we show that the increased phagocytosis was not a result of cellular activation or cellular heterogeneity but was driven by changes in cell membrane fluidity and cellular compliance. A consequence of the enhanced phagocytic activity was that particulate-laden immune cells neutralize E. coli faster in culture. Moreover, when administered in mice as a prophylactic, particulates enable faster clearance of E. coli and S. epidermidis. Together, we demonstrate that the process of uptake induces cellular changes that favor additional phagocytic events. This study provides insights into using non-stimulatory cargo-free particles to engineer immune cell functions for applications involving faster clearance of phagocytosable particulates.

immunology↗