Visceral Pain Research Group, Centre for Neuroscience, College of Medicine and Public Health, Flinders University, Bedford Park, South Australia, Australia.
Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, North Terrace, Adelaide, South Australia, Australia, and South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia, Australia.
JCI Insight. 2018 Oct 4;3(19):121841. doi: 10.1172/jci.insight.121841.
Irritable bowel syndrome (IBS) patients suffer from chronic abdominal pain and extraintestinal comorbidities, including overactive bladder (OAB) and interstitial cystitis/painful bladder syndrome (IC-PBS). Mechanistic understanding of the cause and time course of these comorbid symptoms is lacking, as are clinical treatments. Here, we report that colitis triggers hypersensitivity of colonic afferents, neuroplasticity of spinal cord circuits, and chronic abdominal pain, which persists after inflammation. Subsequently, and in the absence of bladder pathology, colonic hypersensitivity induces persistent hypersensitivity of bladder afferent pathways, resulting in bladder-voiding dysfunction, indicative of OAB/IC-PBS. Daily administration of linaclotide, a guanylate cyclase-C (GC-C) agonist that is restricted to and acts within the gastrointestinal tract, reverses colonic afferent hypersensitivity, reverses neuroplasticity-induced alterations in spinal circuitry, and alleviates chronic abdominal pain in mice. Intriguingly, daily linaclotide administration also reverses persistent bladder afferent hypersensitivity to mechanical and chemical stimuli and restores normal bladder voiding. Linaclotide itself does not inhibit bladder afferents, rather normalization of bladder function by daily linaclotide treatment occurs via indirect inhibition of bladder afferents via reduced nociceptive signaling from the colon. These data support the concepts that cross-organ sensitization underlies the development and maintenance of visceral comorbidities, while pharmaceutical treatments that inhibit colonic afferents may also improve urological symptoms through common sensory pathways.
肠易激综合征(IBS)患者患有慢性腹痛和肠道外合并症,包括膀胱过度活动症(OAB)和间质性膀胱炎/疼痛性膀胱综合征(IC-PBS)。这些合并症症状的原因和时间过程的机制理解以及临床治疗方法都很缺乏。在这里,我们报告结肠炎引发结肠传入神经的过敏反应、脊髓回路的神经可塑性和慢性腹痛,这些在炎症消退后仍然存在。随后,在没有膀胱病理的情况下,结肠过敏反应会引起膀胱传入神经通路的持续过敏反应,导致膀胱排空功能障碍,表现为 OAB/IC-PBS。每天给予 linaclotide(一种仅作用于胃肠道的鸟苷酸环化酶-C(GC-C)激动剂)可逆转结肠传入神经过敏反应,逆转脊髓回路中神经可塑性诱导的改变,并缓解小鼠的慢性腹痛。有趣的是,每日给予 linaclotide 还可逆转对机械和化学刺激的持续膀胱传入神经过敏反应,并恢复正常的膀胱排空。Linaclotide 本身不会抑制膀胱传入神经,而是通过减少来自结肠的伤害性信号,通过间接抑制膀胱传入神经来实现对膀胱功能的正常化。这些数据支持这样的概念,即跨器官敏化是内脏合并症发展和维持的基础,而抑制结肠传入神经的药物治疗也可能通过共同的感觉途径改善泌尿科症状。