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Pellegrino, K.

Publications and source records attributed to Pellegrino, K..

3 recordsLinked to original sources

Identification of a Thermogenic Target in the Dorsal Raphe Nucleus for Weight Management

Obesity emerges from a complex interplay of factors, including imbalanced interoception, genetic predisposition, and environmental cues, ultimately disrupting body weight homeostasis1. While much research has concentrated on strategies to suppress appetite for sustained weight loss, insufficient attention has been given to counterregulatory mechanisms that promote energy expenditure. Here, we show that chronic inhibition of GABAergic neurons in the Dorsal Raphe Nucleus (DRNVGAT) reduces body weight in diet-induced obese (DIO) mice. In this study, molecular profiling and in-situ hybridization in rodent and human brains revealed that the constitutively activated orphan receptor GPR6 is selectively enriched in DRNVGAT neurons. We next developed and administered a potent and highly selective GPR6 inverse agonist, which significantly reduced weight gain in DIO mice by stimulating brown adipose tissue thermogenesis without affecting appetite. Altogether, this study transitions from transcriptomic profiling, high-throughput drug screening and metabolic phenotyping to successfully identify a novel candidate to treat obesity.

neuroscience↗

TDP-43 pathology links innate and adaptive immunity in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis is the most common fatal motor neuron disease. Approximately 90% of ALS patients exhibit pathology of the master RNA regulator, Transactive Response DNA Binding protein (TDP-43). Despite the prevalence TDP-43 pathology in ALS motor neurons, recent findings suggest immune dysfunction is a determinant of disease progression in patients. Whether TDP-43 pathology elicits disease-modifying immune responses in ALS remains underexplored. In this study, we demonstrate that TDP-43 pathology is internalized by antigen presenting cells, causes vesicle rupture, and leads to innate and adaptive immune cell activation. Using a multiplex imaging platform, we observed interactions between innate and adaptive immune cells near TDP-43 pathological lesions in ALS brain. We used a mass cytometry-based whole-blood stimulation assay to provide evidence that ALS patient peripheral immune cells exhibit responses to TDP-43 aggregates. Taken together, this study provides a novel link between TDP-43 pathology and ALS immune dysfunction, and further highlights the translational and diagnostic implications of monitoring and manipulating the ALS immune response.

cell biology↗

A Simple Subcortical Feeding Circuit Linking Interoceptive Inputs to Consummatory Behavior

The brain processes an array of stimuli enabling the selection of an appropriate behavioural response but the neural pathways linking interoceptive inputs to outputs for feeding are poorly understood. Here we delineate a subcortical circuit in which brain-derived neurotrophic factor (BDNF) expressing neurons in the ventromedial hypothalamus (VMH) directly connect interoceptive inputs to motor centers controlling food consumption and jaw movements. VMHBDNF neuron inhibition increases food intake by gating motor sequences of feeding through projections to premotor areas of the jaw. When food is unavailable, VMHBDNF inhibition elicits consummatory behaviors directed at inanimate objects such as a wooden block and inhibition of mesencephalic trigeminal area (Me5) projections evokes rhythmic jaw movements. The activity of these neurons is decreased during food consumption and increases when food is in proximity but not consumed. Activity is also increased in obese animals and after leptin treatment. VMHBDNF neurons receive monosynaptic inputs from both agouti-related peptide (AgRP) and proopiomelanocortin (POMC) neurons in the arcuate nucleus (Arc) and constitutive VMHBDNF activation blocks the orexigenic effect of AgRP activation. These data delineate an Arc[->]VMHBDNF[->]Me5 circuit that senses the energy state of an animal and regulates consummatory behaviors in a state dependent manner.

neuroscience↗