Pelot Nicole A, Grill Warren M
Department of Biomedical Engineering, Duke University, Room 1427, Fitzpatrick CIEMAS, 101 Science Drive, Campus Box 90281, Durham, NC, USA.
Department of Biomedical Engineering, Duke University, Room 1427, Fitzpatrick CIEMAS, 101 Science Drive, Campus Box 90281, Durham, NC, USA; Department of Electrical and Computer Engineering, Duke University, Room 130, Hudson Hall, Campus Box 90291, Durham, NC, USA; Department of Neurobiology, Duke University, Room 101B, Bryan Research Building, 311 Research Drive, Campus Box 3209, Durham, NC, USA; Department of Neurosurgery, Duke University School of Medicine, Durham, NC, USA.
Brain Res. 2018 Aug 15;1693(Pt B):180-187. doi: 10.1016/j.brainres.2018.02.003. Epub 2018 Feb 7.
Implanted vagus nerve stimulation (VNS) for obesity was recently approved by the FDA. However, its efficacy and mechanisms of action remain unclear. Herein, we synthesize clinical and preclinical effects of VNS on feeding behavior and energy balance and discuss engineering considerations for understanding and improving the therapy. Clinical cervical VNS (≤30 Hz) to treat epilepsy or depression has produced mixed effects on weight loss as a side effect, albeit in uncontrolled, retrospective studies. Conversely, preclinical studies (cervical and subdiaphragmatic VNS) mostly report decreased food intake and either decreased weight gain or weight loss. More recent clinical studies report weight loss in response to kilohertz frequency VNS applied to the subdiaphragmatic vagi, albeit with a large placebo effect. Rather than eliciting neural activity, this therapy putatively blocks conduction in the vagus nerves. Overall, stimulation parameters lack systematic exploration, optimization, and justification based on target nerve fibers and therapeutic outcomes. The vagus nerve transduces, transmits, and integrates important neural (efferent and afferent), humoral, energetic, and inflammatory information between the gut and brain. Thus, improved understanding of the biophysics, electrophysiology, and (patho)physiology has the potential to advance VNS as an effective therapy for a wide range of diseases.
植入式迷走神经刺激（VNS）用于治疗肥胖症最近已获美国食品药品监督管理局（FDA）批准。然而，其疗效和作用机制仍不清楚。在此，我们综合了VNS对进食行为和能量平衡的临床及临床前效应，并讨论了理解和改进该疗法的工程学考量。临床应用于治疗癫痫或抑郁症的颈部VNS（≤30赫兹）作为副作用对体重减轻产生了不同的影响，尽管这些研究是无对照的回顾性研究。相反，临床前研究（颈部和膈下VNS）大多报告食物摄入量减少以及体重增加减少或体重减轻。最近的临床研究报告称，应用于膈下迷走神经的千赫兹频率VNS可导致体重减轻，尽管存在较大的安慰剂效应。这种疗法并非引发神经活动，而是推测会阻断迷走神经中的传导。总体而言，刺激参数缺乏基于目标神经纤维和治疗结果的系统探索、优化及论证。迷走神经在肠道和大脑之间传导、传递并整合重要的神经（传出和传入）、体液、能量及炎症信息。因此，更好地理解生物物理学、电生理学及（病理）生理学有潜力推动VNS成为治疗多种疾病的有效疗法。
