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Biology subjects

Romero, A. G.

Publications and source records attributed to Romero, A. G..

3 recordsLinked to original sources

Dopamine signaling drives skin invasion by human-infective nematodes

Skin-penetrating nematodes are one of the most prevalent causes of disease worldwide - nearly 15% of the global population is infected with at least one species of skin-penetrating nematode1,2. The World Health Organization has targeted these parasites for elimination by 20303, but the lack of preventative measures is a major obstacle to this goal. The infective larvae of skin-penetrating nematodes enter hosts through skin4, and blocking skin penetration is an as-yet unexplored approach for preventing infection. However, in order to prevent worm ingress via the skin, an understanding of the behavioral and neural mechanisms that drive skin penetration is required. Here, we describe the skin-penetration behaviors of the human-infective threadworm Strongyloides stercoralis. Using fluorescently labeled worms to enable visualization on the skin coupled with time-lapse microscopy, we show that S. stercoralis engages in repeated cycles of pushing, puncturing, and crawling on the skin surface before penetrating the skin. Pharmacological inhibition of dopamine signaling inhibits these behaviors in S. stercoralis and the human hookworm Ancylostoma ceylanicum, suggesting a critical role for dopamine signaling in driving skin penetration across distantly related nematodes. CRISPR-mediated disruption of dopamine biosynthesis and chemogenetic silencing of dopaminergic neurons also inhibit skin penetration. Finally, inactivation of the TRPN channel TRP-4, which is expressed in the dopaminergic neurons, blocks skin penetration on both rat and human skin. Our results suggest that drugs targeting TRP-4 and other nematode-specific components of the dopaminergic pathway could be developed into topical prophylactics that block skin penetration, thereby preventing infections.

neuroscience↗

A first-in-kind MAPK13 inhibitor that can correct stem cell reprogramming and post-injury disease

The stress kinase MAPK13 (aka p38delta-MAPK) is an attractive entry point for therapeutic intervention because it regulates the structural remodeling that can develop after epithelial injury in the lung and likely other tissue sites. However, a selective, safe, and effective MAPK13 inhibitor is not yet available for experimental or clinical application. Here we identify a first-in-kind MAPK13 inhibitor using structure-based drug design combined with a screening funnel for cell safety and molecular specificity. In a mouse model of severe respiratory viral infection, treatment with this inhibitor (formulated as NuP-4A for intravenous use or Nu4-B for inhaled delivery) did not influence recovery from acute infectious illness, but still down-regulated basal-epithelial stem cell (basal-ESC) hyperplasia/metaplasia and in turn airway inflammation, mucus production, and pathophysiology biomarkers of chronic lung disease. Treatment prevented and reversed disease readouts equivalently to Mapk13 gene-knockout, and this benefit persisted after stopping treatment as a sign of disease modification. Further, NuP-4 treatment even at pM levels directly blocked basal-ESC reprogramming endpoints in organoid and cell-culture models derived from non-disease control and asthma subjects. The results thereby provide a new tool compound and drug candidate for basal-ESC reprogramming towards muco-obstructive lung diseases like asthma and any overlap with COPD and related diseases that depend on overactivity of MAPK13.

immunology↗

A new MAPK13-guided inhibitor for respiratory inflammation and mucus production

Common respiratory diseases continue to represent a major public health problem, and much of the morbidity and mortality is due to airway inflammation and mucus production. Previous studies indicated a role for mitogen-activated protein kinase 14 (MAPK14) in this type of disease, but clinical trials are unsuccessful to date. Our previous work identified a related but distinct kinase known as MAPK13 that is activated in respiratory airway diseases and is required for mucus production in human cell-culture models. Support for MAPK13 function in these models came from effectiveness of MAPK13 versus MAPK14 gene-knockdown and from first-generation MAPK13-14 inhibitors. However, these first-generation inhibitors were incompletely optimized for blocking activity and were untested in vivo. Here we report the next generation and selection of a potent MAPK13-14 inhibitor (designated NuP-3) that more effectively down-regulates type-2 cytokine-stimulated mucus production in air-liquid interface and organoid cultures of human airway epithelial cells. We also show that NuP-3 treatment prevents respiratory airway inflammation and mucus production in new minipig models of airway disease triggered by type-2 cytokine challenge or respiratory viral infection. The results thereby provide the next advance in developing a small-molecule kinase inhibitor to address key features of respiratory disease. New and noteworthyThis study describes the discovery of a potent MAPK13-14 inhibitor and its effectiveness in models of respiratory airway disease. The findings thereby provide a scheme for pathogenesis and therapy of lung diseases (e.g., asthma, COPD, Covid-19, post-viral and allergic respiratory disease) and related conditions that implicate MAPK13-14 function. The findings also refine a hypothesis for epithelial and immune cell functions in respiratory disease that features MAPK13 as a possible component of this disease process.

immunology↗