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Klein, M. E.

Publications and source records attributed to Klein, M. E..

2 recordsLinked to original sources
bioRxiv2022

A Novel Mouse Model of Chronic Primary Pain Conditions that Integrates Clinically Relevant Genetic and Environmental Factors

Chronic primary pain conditions (CPPCs) affect over 100 million people, predominantly women. Yet, they remain ineffectively treated due, in large part, to lack of valid animal models with translational relevance. Here, we characterized a novel mouse model of CPPCs that integrated clinically-relevant genetic (catechol-o-methyltransferase; COMT knockdown) and environmental (stress and minor injury) factors. Compared to wildtype mice, COMT+/- mice undergoing the repeated swim stress and molar extraction surgery intervention exhibited pronounced multi-site body pain and depressive-like behavior lasting more than 3 months. The COMT+/- mice undergoing the intervention also exhibited enhanced activity of primary afferent DRG nociceptors innervating hindpaw and back sites and increased plasma levels of norepinephrine and the pro-inflammatory cytokines IL-6 and IL-17A. Notably, the pain and depressive-like behavior was of greater magnitude and longer duration (lasting at least 12 months) in females compared to males. Further, increases in anxiety-like behavior and IL-6 levels were female-specific. Intervention-induced body pain and nociception in COMT+/- mice was blocked by a beta-3 adrenergic antagonist, demonstrating predictive validity. Finally, the effect of COMT genotype x stress interactions on pain and IL-6 and IL-17A levels was observed in our clinical CPPC case-control cohort, demonstrating construct validity. Thus, our novel mouse model reliably recapitulates clinically- and biologically-relevant features of CPPCs and can be further implemented to test underlying mechanisms and discover new therapeutics. One Sentence SummaryWe developed a novel mouse model of chronic primary pain conditions that shares similar genetic, biologic, and clinical features of patients.

neuroscience↗
bioRxiv2020

A gut sensor for sugar preference

Summary Paragraph/AbstractAnimals innately prefer caloric sugars over non-caloric sweeteners. Such preference depends on the sugar entering the intestine.1-4 Although the brain is aware of the stimulus within seconds,5-8 how the gut discerns the caloric sugar to guide choice is unknown. Recently, we discovered an intestinal transducer, known as the neuropod cell.9,10 This cell synapses with the vagus to inform the brain about glucose in the gut in milliseconds.10 Here, we demonstrate that neuropod cells distinguish a caloric sugar from a non-caloric sweetener using the electrogenic sodium glucose co-transporter 1 (SGLT1) or sweet taste receptors. Activation of neuropod cells by non-caloric sucralose leads to ATP release, whereas the entry of caloric sucrose via SGLT1 stimulates glutamate release. To interrogate the contribution of the neuropod cell to sugar preference, we developed a method to record animal preferences in real time while using optogenetics to silence or excite neuropod cells. We discovered that silencing these cells, or blocking their glutamatergic signaling, renders the animals unable to recognize the caloric sugar. And, exciting neuropod cells leads the animal to consume the non-caloric sweetener as if it were caloric. By transducing the precise identity of the stimuli entering the gut, neuropod cells guide an animals internal preference toward the caloric sugar.

neuroscience↗