Severe gastrointestinal dysmotility developed after treatment with gonadotropin-releasing hormone analogs

Endoscopic versus Laparoscopic Full-Thickness Biopsy in the Pathological Evaluation of the Enteric Nervous System

A full-thickness biopsy of the bowel wall is required to evaluate the enteric nervous system. A patient with aggravating gastrointestinal symptoms underwent a laparoscopic full-thickness biopsy of the ileum and, 1 year later, an endoscopic full-thickness biopsy of the sigmoid colon. Both samples showed enteric neuropathy characterized by vacuolated and enlarged neurons. The length of the myenteric plexus was greater in the endoscopic (23 mm) compared to the laparoscopic (11 mm) biopsy, with fewer tissue artefacts in the laparoscopic approach. Clinical deterioration was paralleled by enteric neuropathy with an increase in the percentage of vacuolated and enlarged enteric neurons from 24 to 35%.

Gonadotropin-Releasing Hormone and Its Role in the Enteric Nervous System

Gonadotropin-releasing hormone (GnRH), follicle-stimulating hormone, and luteinizing hormone orchestrate the reproduction cycle and regulate the sex steroid secretion from the gonads. In mammals, GnRH1 is secreted as a hormone from the hypothalamus, whereas both GnRH1 and GnRH2 are present as neurotransmitters/peptides in various tissues, where the peptides exert many different effects. mRNA coding for GnRH1 and GnRH2 have been described in the human gastrointestinal tract, and GnRH has been found in both submucosal and myenteric neurons. mRNA coding for GnRH and the fully expressed peptide have been found in rat enteric neurons by some researchers but not by others. mRNA coding for GnRH receptors, but not the fully expressed receptor, has been found in one rat study. GnRH influences gastrointestinal motility and secretion. GnRH analogs are clinically used in the treatment of sex hormone-dependent diseases, i.e., endometriosis and malignancies, and as pretreatment for in vitro fertilization. Reduced numbers of enteric neurons and IgM antibodies against GnRH and progonadoliberin-2 (precursor of GnRH2) have been observed after such treatment, with the clinical picture of gastrointestinal dysmotility. Similarly, a rat model of enteric neurodegeneration has been developed after administration of the GnRH analog buserelin. Serum IgM antibodies against GnRH1, progonadoliberin-2, and GnRH receptors have been described in patients with signs and symptoms of gastrointestinal dysmotility and/or autonomic dysfunction, such as irritable bowel syndrome, enteric dysmotility, diabetes mellitus, and primary Sjögren's syndrome. Thus, apart from regulation of reproduction and sex hormone secretion, GnRH also constitutes a part of enteric nervous system (ENS) and its functions during physiological and pathological conditions. This review aimed to describe the role of GnRH in the ENS.

In vivo and vitro characterization of the effects of kisspeptin-13, endogenous ligands for GPR54, on mouse gastrointestinal motility

Kisspeptin (KP), the endogenous ligand of GPR54, is a mammalian amidated neurohormone, which belongs to the RF-amide peptide family. However, in contrast with the related members of the RF-amide family, little information is available regarding its role in the gastrointestinal motility. With regard to the recent data suggesting KP play an important role in food intake, and while gastrointestinal motility are closely related to it. Thus, in the present work, effects of central administration of KP-13, one of the endogenous active isoforms, on gastrointestinal motility were investigated. The results indicated that intracerebroventricular (i.c.v.) infused of KP-13 significantly facilitated gastrointestinal transit, bead expulsion and fecal pellet output, respectively, while has no effect on gastric emptying. The effects were significantly reversed by GPR54 antagonist 234, but not GnRH receptor antagonist Cetrorelix. However, i.p. injected of KP-13 or compound 5 (10mg/kg), a high metabolic stability kisspeptin analog, did not affect gastrointestinal transit, suggesting that KP-13 or compound 5 facilitated gastrointestinal transit through the activation of central GPR54. Then the gastrointestinal motility-enhancing effects were also presented after infusion of KP-13 into the hypothalamus. In vitro, KP-13 (10^-6M) also modulated colonic contraction, but not in the stomach and small intestine. Similarly, KP-13 (10^-6M)-induced contractions of circular and longitudinal colonic muscle were significantly attenuated by antagonist 234 (10^-6M). In conclusion, all the results indicated that KP-13 promoted gastrointestinal motility through the activation of GPR54, which implicate that KP/GPR54 system might be a new target to treat gastrointestinal function disorder.

Long‑term follow‑up of buserelin‑induced enteric neuropathy in rats

A few patients have been shown to develop severe abdominal pain and gastrointestinal dysmotility during treatment with gonadotropin‑releasing hormone (GnRH) analogs. A rat model of enteric neuropathy has been developed by administration of the GnRH analog buserelin to rats. Loss of enteric neurons and ganglioneuritis throughout the gastrointestinal tract has been described, without other histopathological changes. The aim of the present study was to investigate the long‑term effects of this rat model on body weight, and on morphology and inflammatory changes in the gastrointestinal tract. Rats were administered subcutaneous injections of buserelin or saline once daily for 5 days and allowed to recover for 3 weeks. This regimen was repeated four times. The rats were weighed weekly and were sacrificed 16 weeks after the fourth treatment. The bowel wall was measured by morphometry, and the presence of enteric neurons, mast cells, eosinophils and T‑lymphocytes was evaluated. Buserelin‑treated rats were shown to have a lower body weight at sacrifice, as compared with the controls (P<0.05). Compared with controls, buserelin treatment caused loss of myenteric neurons in the ileum and colon (P<0.01), a thinner circular muscle layer in ileum (P<0.05) and longitudinal muscle layer in colon (P<0.05), increased number of eosinophils in the submucosa of the ileum (P<0.05), and an increased number of T‑lymphocytes in the submucosa and circular muscle layer of the fundus (P<0.01 and P<0.05, respectively) and circular muscle layer of the colon (P<0.05). Mast cells were equally distributed in the two groups. Thus, long‑term follow‑up of buserelin‑induced enteric neuropathy reveals reduced body weight, loss of myenteric neurons, thinning of muscle layers, and increased numbers of eosinophils and T‑lymphocytes in the gastrointestinal tract.

Gonadotropin-Releasing Hormone and Its Physiological and Pathophysiological Roles in Relation to the Structure and Function of the Gastrointestinal Tract

<b><i>Background:</i></b> Gonadotropin-releasing hormone (GnRH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) are involved in the reproductive cycle and regulate the secretion of sex steroids from the gonads. In mammals, GnRH1 is secreted as a hormone from the hypothalamus, whereas both GnRH1 and GnRH2 are present as neuropeptides in a variety of tissues. This review describes the role of GnRH in the gastrointestinal tract. <b><i>Summary:</i></b> GnRH1, GnRH2, and LH receptors in humans and rats, and GnRH receptors in rats, have been described in the gastrointestinal tract, where they affect motility, gastric and hormone secretion, and cell proliferation. GnRH analogs are clinically used in the treatment of sex hormone-dependent diseases, i.e., endometriosis and malignancies, and as pretreatments for in vitro fertilization. Severe gastrointestinal dysmotility has been shown to develop in some women after such treatment, along with a reduction in the number of enteric neurons and autoantibodies against GnRH. Consequently, a rat model of enteric neurodegeneration has been developed based on the administration of the GnRH analog buserelin. Serum IgM antibodies against GnRH1, the GnRH2 precursor progonadoliberin-2, and the GnRH receptor have also been described in patients with irritable bowel syndrome and dysmotility, as well as in patients with gastrointestinal disorders associated with diabetes mellitus, posterior laryngitis, and primary Sjögren's syndrome, although no treatments using GnRH analogs have been administered. <b><i>Conclusion:</i></b> GnRH and receptors for GnRH and LH are present in the human and rat gastrointestinal tract. Treatment with GnRH analogs may induce severe dysmotility, and a rat model of enteric neurodegeneration has been developed based on stimulation by the GnRH analog buserelin. Autoantibodies against GnRH and its receptor are found in a subgroup of patients with functional bowel disorders and dysmotility, independent of treatment with GnRH analogs.

Buserelin treatment to rats causes enteric neurodegeneration with moderate effects on CRF-immunoreactive neurons and Enterobacteriaceae in colon, and in acetylcholine-mediated permeability in ileum

Background

The gonadotropin-releasing hormone (GnRH) analog buserelin causes enteric neuronal loss. Acute stress or injection of corticotropin-releasing factor (CRF) affects motility, secretion, and barrier function of the gastrointestinal tract. The aim of the study was to characterize the CRF immunoreactivity in enteric neurons after buserelin treatment, and to evaluate possible effects of enteric neuropathy on gut microbiota, intestinal permeability, and stress response behavior.

Results

Sixty rats were given buserelin (20 μg) or saline subcutaneously for 5 days, repeated four times with 3 weeks in-between. At the study end, enteric neuronal density, enteric expression of CRF, gut microbial composition, and plasma levels of adrenocorticotropic hormone (ACTH) and CRF were analyzed. Intestinal permeability was examined in Ussing chambers and the reaction to stressful events was measured by behavior tests. Buserelin treatment reduced the number of neurons along the entire gastrointestinal tract, with increased relative numbers of CRF-immunoreactive submucosal and myenteric neurons in colon (p < 0.05 and p < 0.01, respectively). The overall microbial diversity and relative abundance did not differ between groups, but Enterobacteriaceae was decreased in colon in buserelin-treated rats (p = 0.020). Basal intestinal permeability did not differ between groups, whereas carbachol stimulation increased ileum permeability in controls (p < 0.05), but not in buserelin-treated rats. Buserelin did not affect stress behavior.

Conclusions

Although buserelin treatment leads to enteric neuronal loss along the gastrointestinal tract with an increased percentage of CRF-immunoreactive neurons in colon, the physiology is well preserved, with modest effects on colon microbiota and absence of carbachol-induced permeability in ileum as the only observed changes.

Electronic supplementary material

The online version of this article (doi:10.1186/s13104-015-1800-x) contains supplementary material, which is available to authorized users.

Gastrointestinal symptoms among endometriosis patients--A case-cohort study

Background

Women with endometriosis often experience gastrointestinal symptoms. Gonadotropin-releasing hormone (GnRH) analogs are used to treat endometriosis; however, some patients develop gastrointestinal dysmotility following this treatment. The aims of the present study were to investigate gastrointestinal symptoms among patients with endometriosis and to examine whether symptoms were associated with menstruation, localization of endometriosis lesions, or treatment with either opioids or GnRH analogs, and if hormonal treatment affected the symptoms.

Methods

All patients with diagnosed endometriosis at the Department of Gynecology were invited to participate in the study. Gastrointestinal symptoms were registered using the Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS); socioeconomic and medical histories were compiled using a clinical data survey. Data were compared to a control group from the general population.

Results

A total of 109 patients and 65 controls were investigated. Compared to controls, patients with endometriosis experienced significantly aggravated abdominal pain (P = 0.001), constipation (P = 0.009), bloating and flatulence (P = 0.000), defecation urgency (P = 0.010), and sensation of incomplete evacuation (P = 0.050), with impaired psychological well-being (P = 0.005) and greater intestinal symptom influence on their daily lives (P = 0.001). The symptoms were not associated with menstruation or localization of endometriosis lesions, except increased nausea and vomiting (P = 0.010) in patients with bowel-associated lesions. Half of the patients were able to differentiate between abdominal pain from endometriosis and from the gastrointestinal tract. Patients using opioids experienced more severe symptoms than patients not using opioids, and patients with current or previous use of GnRH analogs had more severe abdominal pain than the other patients (P = 0.024). Initiation of either combined oral contraceptives or progesterone for endometriosis had no effect on gastrointestinal symptoms when the patients were followed prospectively.

Conclusions

The majority of endometriosis patients experience more severe gastrointestinal symptoms than controls. A poor association between symptoms and lesion localization was found, indicating existing comorbidity between endometriosis and irritable bowel syndrome (IBS). Treatment with opioids or GnRH analogs is associated with aggravated gastrointestinal symptoms.

The Expression of Serum Antibodies Against Gonadotropin-releasing Hormone (GnRH1), Progonadoliberin-2, Luteinizing Hormone (LH), and Related Receptors in Patients with Gastrointestinal Dysfunction or Diabetes Mellitus

Gonadotropin-releasing hormone (GnRH) 1 and 2 and luteinizing hormone (LH) receptors have been described in the gastrointestinal tract. We have previously demonstrated antibodies in serum against GnRH1 in patients with gastrointestinal dysfunction and diabetes mellitus, and antibodies against GnRH receptor, LH, and LH receptor in patients with infertility. The aim of this study was to search for the expression of serum antibodies against GnRH1 with an improved enzyme-linked immune sorbent assay (ELISA), and antibodies against progonadoliberin-2, GnRH2, GnRH receptor, LH, and LH receptor with newly developed ELISAs, in patients with gastrointestinal dysfunction or diabetes mellitus. Healthy blood donors served as controls. Medical records were scrutinized. Our conclusion was that IgM antibodies against GnRH1, progonadoliberin-2, and/or GnRH receptors were more prevalent in patients with functional gastrointestinal disorders, gastrointestinal dysmotility, and/or diabetes mellitus, whereas IgG antibodies against these peptides, and LH- and LH receptor antibodies, were expressed in the same magnitude as in controls.