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Castaldi, L.

Publications and source records attributed to Castaldi, L..

3 recordsLinked to original sources

Cross-generational characterization of paternal Low Protein Diet effects in mice

The impact of diet on the physiology of organisms and their progeny has been well documented across phyla. Using the established paternal Low Protein (LP) diet paradigm in mice, here we assess the robustness of the diet-induced intergenerational responses upon variation of genetic background and dietary history of tested animals. Protein restriction in FVB/NCrl resulted in mild, but specific hepatic responses in exposed animals, as well as their F1 progeny, affecting fatty acid metabolism and cholesterol biosynthesis, respectively. These phenotypes were qualitatively conserved between FVB/NCrl and C56BL/6J mice, suggesting the existence of shared molecular mechanisms underlying metabolic reprogramming, modulated in magnitude by genetic background. Unexpectedly, we uncover cumulative intergenerational inheritance effects that get reshaped at every generation, and a sex-specific priming of cholesterol metabolism of LP-sired F1 offspring, evident upon dietary challenge. Together, our data, spanning multigenerational physiology, transcriptomics and lipidomics, indicate that the phenotypic consequences of paternal LP consumption depend on the duration and/or on the interaction of dietary exposure across generations, leading to distinct trajectories in hepatic energy metabolism.

molecular biology↗

Identification of a novel population of peripheral sensory neuron that regulates blood pressure

The vasculature is innervated by a network of peripheral afferents that sense and regulate blood flow. Here, we describe a system of non-peptidergic sensory neurons with cell bodies in the spinal ganglia that regulate vascular tone in the distal arteries. We identify a population of mechanosensitive neurons marked by TrkC and Tyrosine hydroxylase in the dorsal root ganglia that project to blood vessels. Local stimulation of these neurons decreases vessel diameter and blood flow, while systemic activation increases systolic blood pressure and heart rate variability via the sympathetic nervous system. Chemogenetic inactivation or ablation of the neurons provokes variability in local blood flow leading to a reduction in systolic blood pressure, increased heart rate variability and ultimately lethality within 48 hours. Thus, TrkC/Tyrosine hydroxylase positive sensory neurons form part of a sensory feedback mechanism that maintains cardiovascular homeostasis through the autonomic nervous system.

neuroscience↗

Molecule guided laser ablation as a novel therapeutic strategy to control itch.

Itch is a major symptom of many chronic skin diseases that can exacerbate inflammation by provoking excessive scratching and causing skin damage. Here we develop a novel technology to control itch through molecular guided delivery of a phototoxic agent and near infrared (IR) illumination of the skin. Exploiting the selective binding of the pruritogen Interleukin-31 to itch sensing cells, we generate an engineered IL31SNAP ligand derivative (IL31K138A-SNAP) that binds to cells but does not evoke signaling or provoke scratching when injected in vivo. Conjugation of IL31K138A-SNAP to the photosensitizer IRDye(R)700DX phthalocyanine (IR700) and injection of the skin results in long-term reversal of scratching behavior evoked by IL31 upon near IR illumination. We further develop a topical preparation of IL31 K138A-SNAP-IR700 that strikingly, reverses behavioral and dermatological indicators in mouse models of Atopic Dermatitis (AD) and the genetic skin disease Familial Primary Localized Cutaneous Amyloidosis (FPLCA). We demonstrate that this therapeutic effect results from selective retraction of itch sensing neurons in the skin, breaking the cycle of itch and disruption of the skins barrier function. Thus, molecule guided photoablation is a powerful new technology for controlling itch and treating inflammatory skin diseases.

neuroscience↗