Leptin-activated hypothalamic BNC2 neurons acutely suppress food intake.

Leptin is an adipose tissue hormone that maintains homeostatic control of adipose tissue mass by regulating the activity of specific neural populations controlling appetite and metabolism. Leptin regulates food intake by inhibiting orexigenic agouti-related protein (AGRP) neurons and activating anorexigenic pro-opiomelanocortin (POMC) neurons. However, whereas AGRP neurons regulate food intake on a rapid time scale, acute activation of POMC neurons has only a minimal effect.

A subcortical feeding circuit linking an interoceptive node to jaw movement.

The brain processes an array of stimuli, enabling the selection of appropriate behavioural responses, 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 centres, controlling food consumption and jaw movements. VMH neuron inhibition increases food intake by gating motor sequences of feeding through projections to premotor areas of the jaw.

Bidirectional regulation of motor circuits using magnetogenetic gene therapy.

Here, we report a magnetogenetic system, based on a single anti-ferritin nanobody-TRPV1 receptor fusion protein, which regulated neuronal activity when exposed to magnetic fields. Adeno-associated virus (AAV)-mediated delivery of a floxed nanobody-TRPV1 into the striatum of adenosine-2a receptor-Cre drivers resulted in motor freezing when placed in a magnetic resonance imaging machine or adjacent to a transcranial magnetic stimulation device. Functional imaging and fiber photometry confirmed activation in response to magnetic fields.

The discovery and development of GLP-1 based drugs that have revolutionized the treatment of obesity.

The 2024 Lasker~DeBakey Clinical Medical Research Award has been given to Joel Habener and Svetlana Mojsov for their discovery of a new hormone GLP-1(7-37) and to Lotte Knudsen for her role in developing sustained acting versions of this hormone as a treatment for obesity. Each of the three had a distinct set of skills that made this advance possible; Habener is an endocrinologist and molecular biologist, Mojsov is a peptide chemist, and Knudsen is a pharmaceutical scientist. Their collective efforts have done what few thought possible-the development of highly effective medicines for reducing weight.

The impact of hindsight bias on the diagnosis of perioperative events by anesthesia providers: A multicenter randomized crossover study.

Study Objective: Hindsight bias is the tendency to overestimate the predictability of an event after it has already occurred. We aimed to evaluate whether hindsight bias influences the retrospective interpretation of clinical scenarios in the field of anesthesiology, which relies on clinicians making rapid decisions in the setting of perioperative adverse events.

Design: Two clinical scenarios were developed (intraoperative hypotension and intraoperative hypoxia) with 3 potential diagnoses for each.

Drugs of abuse hijack a mesolimbic pathway that processes homeostatic need.

Drugs of abuse are thought to promote addiction in part by "hijacking" brain reward systems, but the underlying mechanisms remain undefined. Using whole-brain FOS mapping and in vivo single-neuron calcium imaging, we found that drugs of abuse augment dopaminoceptive ensemble activity in the nucleus accumbens (NAc) and disorganize overlapping ensemble responses to natural rewards in a cell type-specific manner. Combining FOS-Seq, CRISPR-perturbation, and single-nucleus RNA sequencing, we identified as a molecular substrate that regulates cell type-specific signal transduction in NAc while enabling drugs to suppress natural reward consumption.

Association of Structural Forms of 17q21.31 with the Risk of Progressive Supranuclear Palsy and Sub-haplotypes.

Importance: The chromosome 17q21.31 region, containing a 900 Kb inversion that defines H1 and H2 haplotypes, represents the strongest genetic risk locus in progressive supranuclear palsy (PSP). In addition to H1 and H2, various structural forms of 17q21.

Staged breast reconstruction utilizing primary nipple repositioning surgery prior to nipple-sparing mastectomy.

Staged nipple-sparing mastectomy (NSM) following mastopexy or breast reduction has become increasingly utilized in patients with large or ptotic breasts. The safety and efficacy of this approach has been demonstrated in recent years. However, the optimal timing between stages has not been established.

Seeking satiety: From signals to solutions.

Remedies for the treatment of obesity date to Hippocrates, when patients with obesity were directed to "reduce food and avoid drinking to fullness" and begin "running during the night." Similar recommendations have been repeated ever since, despite the fact that they are largely ineffective. Recently, highly effective therapeutics were developed that may soon enable physicians to manage body weight in patients with obesity in a manner similar to the way that blood pressure is controlled in patients with hypertension.

Magnetogenetic cell activation using endogenous ferritin.

The ability to precisely control the activity of defined cell populations enables studies of their physiological roles and may provide therapeutic applications. While prior studies have shown that magnetic activation of ferritin-tagged ion channels allows cell-specific modulation of cellular activity, the large size of the constructs made the use of adeno-associated virus, AAV, the vector of choice for gene therapy, impractical. In addition, simple means for generating magnetic fields of sufficient strength have been lacking.

Drugs of abuse hijack a mesolimbic pathway that processes homeostatic need.

Addiction prioritizes drug use over innate needs by "hijacking" brain circuits that direct motivation, but how this develops remains unclear. Using whole-brain FOS mapping and single-neuron calcium imaging, we find that drugs of abuse augment ensemble activity in the nucleus accumbens (NAc) and disorganize overlapping ensemble responses to natural rewards in a cell-type-specific manner. Combining "FOS-Seq", CRISPR-perturbations, and snRNA-seq, we identify as a shared molecular substrate that regulates cell-type-specific signal transductions in NAc while enabling drugs to suppress natural reward responses.

Bidirectional Regulation of Motor Circuits Using Magnetogenetic Gene Therapy Short: Magnetogenetic Regulation of Motor Circuits.

Here we report a novel suite of magnetogenetic tools, based on a single anti-ferritin nanobody-TRPV1 receptor fusion protein, which regulated neuronal activity when exposed to magnetic fields. AAV-mediated delivery of a floxed nanobody-TRPV1 into the striatum of adenosine 2a receptor-cre driver mice resulted in motor freezing when placed in an MRI or adjacent to a transcranial magnetic stimulation (TMS) device. Functional imaging and fiber photometry both confirmed activation of the target region in response to the magnetic fields.

FGF21 counteracts alcohol intoxication by activating the noradrenergic nervous system.

Animals that consume fermenting fruit and nectar are at risk of exposure to ethanol and the detrimental effects of inebriation. In this report, we show that the hormone FGF21, which is strongly induced by ethanol in murine and human liver, stimulates arousal from intoxication without changing ethanol catabolism. Mice lacking FGF21 take longer than wild-type littermates to recover their righting reflex and balance following ethanol exposure.

Resting-state network functional connectivity before and after bariatric surgery.

Background: Bariatric surgery is an increasingly popular treatment for patients with severe obesity and related health issues (e.g., diabetes, cardiovascular disease).

Change in medial frontal cerebral metabolite concentrations following bariatric surgery.

Obesity is associated with adverse effects on brain health, including an increased risk of neurodegenerative diseases. Changes in cerebral metabolism may underlie or precede structural and functional brain changes. While bariatric surgery is known to be effective in inducing weight loss and improving obesity-related medical comorbidities, few studies have examined whether it may be able to improve brain metabolism.

Pharmacological targeting of glutamatergic neurons within the brainstem for weight reduction.

Food intake and body weight are tightly regulated by neurons within specific brain regions, including the brainstem, where acute activation of dorsal raphe nucleus (DRN) glutamatergic neurons expressing the glutamate transporter Vglut3 (DRN) drive a robust suppression of food intake and enhance locomotion. Activating Vglut3 neurons in DRN suppresses food intake and increases locomotion, suggesting that modulating the activity of these neurons might alter body weight. Here, we show that DRN neurons project to the lateral hypothalamus (LHA), a canonical feeding center that also reduces food intake.

Dynamic processing of hunger and thirst by common mesolimbic neural ensembles.

The nucleus accumbens (NAc) is a canonical reward center that regulates feeding and drinking but it is not known whether these behaviors are mediated by same or different neurons. We employed two-photon calcium imaging in awake, behaving mice and found that during the appetitive phase, both hunger and thirst are sensed by a nearly identical population of individual D1 and D2 neurons in the NAc that respond monophasically to food cues in fasted animals and water cues in dehydrated animals. During the consummatory phase, we identified three distinct neuronal clusters that are temporally correlated with action initiation, consumption, and cessation shared by feeding and drinking.

Brainstem ADCYAP1 neurons control multiple aspects of sickness behaviour.

Infections induce a set of pleiotropic responses in animals, including anorexia, adipsia, lethargy and changes in temperature, collectively termed sickness behaviours. Although these responses have been shown to be adaptive, the underlying neural mechanisms have not been elucidated. Here we use of a set of unbiased methodologies to show that a specific subpopulation of neurons in the brainstem can control the diverse responses to a bacterial endotoxin (lipopolysaccharide (LPS)) that potently induces sickness behaviour.

Prevalence of Postoperative Micronutrient Deficiencies in Bariatric Surgery Patients Who Use Transdermal Patches for Supplementation: A Pilot Study.

Background Patients require vitamin and mineral supplementation after bariatric surgery to prevent the development of micronutrient deficiencies. Consuming oral supplements is challenging due to gastric volume restriction. A transdermal patch dosage form may provide adequate micronutrient supplementation without pill burden.

Comparative Safety of Sleeve Gastrectomy and Roux-en-Y: A Propensity Score Analysis.

Background: Use of bariatric surgery has increased dramatically in the USA. However, there are growing concerns regarding the safety outcomes of different bariatric procedures. We aim to compare the safety of sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB), which includes hospital readmissions, emergency room (ER) visits, gastrointestinal bleeding, and revisional surgery.