Tools for noninvasively modulating neural signaling in peripheral organs will advance the study of nerves and their effect on homeostasis and disease. Herein, we demonstrate a noninvasive method to modulate specific signaling pathways within organs using ultrasound (U/S). U/S is first applied to spleen to modulate the cholinergic anti-inflammatory pathway (CAP), and US stimulation is shown to reduce cytokine response to endotoxin to the same levels as implant-based vagus nerve stimulation (VNS). Next, hepatic U/S stimulation is shown to modulate pathways that regulate blood glucose and is as effective as VNS in suppressing the hyperglycemic effect of endotoxin exposure. This response to hepatic U/S is only found when targeting specific sub-organ locations known to contain glucose sensory neurons, and both molecular (i.e. neurotransmitter concentration and cFOS expression) and neuroimaging results indicate US induced signaling to metabolism-related hypothalamic sub-nuclei. These data demonstrate that U/S stimulation within organs provides a new method for site-selective neuromodulation to regulate specific physiological functions.
9 November 2020 in Proceedings of the National Academy of Sciences
Significance: Electronic devices that stimulate electrical activity in the vagus nerve are being studied for clinical use in rheumatoid arthritis, inflammatory bowel disease, and other inflammatory syndromes because vagus nerve signals inhibit inflammation and cytokine production. A vagus nerve mechanism, termed the inflammatory reflex, has been widely studied, but the origin and functional neuroanatomy of vagus nerve fibers controlling inflammation were previously unknown. Here we reveal cholinergic neurons in the brainstem dorsal motor nucleus (DMN) of the vagus projecting to the celiac-superior mesenteric ganglia and transmitting cytokine-inhibiting signals to the splenic nerve. By combining optogenetics, anatomical and functional mapping, and measurement of TNF production, our data show the DMN is an important brainstem locus controlling anti-inflammatory signals in the inflammatory reflex.
9 March 2017 in American Journal of Transplantation
Donation after circulatory death (DCD) liver transplantation (LT) reportedly yields inferior survival and increased complication rates compared with donation after brain death (DBD). We compare 100 consecutive DCD LT using a protocol that includes thrombolytic therapy (late DCD group) to an historical DCD group (early DCD group n = 38) and a cohort of DBD LT recipients (DBD group n = 435). Late DCD LT recipients had better 1‐ and 3‐year graft survival rates than early DCD LT recipients (92% vs. 76.3%, p = 0.03 and 91.4% vs. 73.7%, p = 0.01). Late DCD graft survival rates were comparable to those of the DBD group (92% vs. 93.3%, p = 0.24 and 91.4% vs. 88.2%, p = 0.62). Re‐transplantation occurred in 18.4% versus 1% for the early and late DCD groups, respectively (p = 0.001). Patient survival was similar in all three groups. Ischemic‐type biliary lesions (ITBL) occurred in 5%, 3%, and 0.2% for early DCD, late DCD, and DBD groups, respectively, but unlike in the early DCD group, in the late DCD group ITBL was endoscopically managed and resolved in each case. Using a protocol that includes a thrombolytic therapy, DCD LT yielded patient and graft survival rates comparable to DBD LT.