Su1726 GASTRIC PER-ORAL ENDOSCOPIC MYOTOMY (G-POEM) FOR THE TREATMENT OF GASTROPARESIS (GP): A PROSPECTIVE SINGLE CENTER EXPERIENCE TO ASSESS IMPACT ON QUALITY OF LIFE (QOL) Lennon Gregor, John M. Wo, John M. DeWitt, Sarah A. Stainko, Anita Gupta, Brandon Yim, Martha Mendez, Thomas V. Nowak, Mohammad A. Al-Haddad Introduction: G-POEM is pylorus-directed therapy that is hypothesized to accelerate gastric emptying in order to improve symptoms and QOL in patients with GP. Early feasibility studies have demonstrated safety and early clinical success, yet few studies have evaluated impact of QOL. Aim: To assess the short and intermediate term clinical efficacy and impact on QOL, up to 12 months, in patients with GP after G-POEM. Methods: Using a prospectively maintained G-POEM database, patients with confirmed diagnosis of GP by 4-hour solid- phase gastric scintigraphy (GES) within one year of presentation were included. All patients were assessed at baseline and then at 1, 3, 6 and 12 months post G-POEM. Patients were evaluated pre- and post-procedure with EGD, 4-hr scintigraphy, pyloric EndoFLIP®, and antroduodenal manometry. In addition, validated symptom and QOL instruments were utilized: Gastroparesis Cardinal Symptom Index (GCSI), Patient Assessment of Gastrointesti- nal Disorders Symptom Severity Index (PAGI-SYM ), and SF-36. G-POEM was completed by creating mucosal incision at a site orientated about 5 cm proximal to the pylorus. A tunnel was created by dissecting the submucosa, the pyloric muscle isolated, and a short 2 cm myotomy (circular or full thickness) at 6 o’clock was performed. The incision was closed using endoscopic suturing. Technical success was defined as the ability to perform a minimum of circular pyloromyotomy. A two-sample t-test was used to compare baseline measurements to those post G-POEM. Results: 34 patients (median age: 49 yrs, range 28-80, 82% female) underwent G-POEM between February 2018 to October 2019 for diabetic (n=16); idiopathic (n=14) and post-surgical (n=4) GP. The phenotypes of patients included: vomiting predomi- nant (VP) (n=24), dyspepsia-predominant (DP) (n=8), and regurgitation predominant (RP) (n=2). The technical success rates was 100%. There were adverse events in 3/34 (GI bleeding in one and mucosal incision leaks in two) that were successfully managed endoscopically. A significant improvement in PAGI-SYM and GCSI scores was observed at 1, 3, and 6 months compared to baseline, and significant improvement was noted in some domains of SF-36 (Table). GES significantly improved at 6 months post G-POEM (mean 4-hour retention of 6.3% post G-POEM compared to 32.9% baseline, p < 0.001). At 1 month follow up, 12/ 15 (80%) of VP, 2/5 (40%) DP, and 0/2 (0%) RP patients had greater or equal to 1 improvement in total GCSI score. Conclusion: G-POEM appears to be a safe and feasible treatment alternative for GP with significant short and mid-term improvements in symptom and QOL scores. RP and VP gastroparesis phenotypes might be more suited to respond to G-POEM. A larger cohort of patients is needed to validate these findings and examine the long-term effect of G-POEM on patients’ well-being and healthcare utilization. Su1727 SUPPLEMENTATION OF 17β-ESTRADIOL NORMALIZES RAPID GASTRIC EMPTYING BY RESTORING IMPAIRED NRF2 AND NEURONAL NITRIC OXIDE SYNTHASE FUNCTION IN OBESITY-INDUCED DIABETIC OVARIECTOMIZED MICE Jeremy Sprouse, Chethan Sampath, Pandu R. Gangula Background: Gastroparesis (Gp)is a multifactorial condition commonly observed in females and characterized by abnormal delayed or rapid gastric emptying (GE) in the absence of mechanical obstruction. GE is reported to be faster in post-menopause, when compared to premenopausal women- likely due to variations in endogenous sex steroid hormones. More- over, the loss of ovarian function and reduced circulatory hormone levels have also been linked to increased risks of development of metabolic syndrome, hallmarked by obesity, hyperinsulinemia, and type II diabetes (T2DM). Several lines of evidence suggest that sex hormones, estrogens in particular, are protective against complications of obesity, diabetes, inflammation, and oxidative stress- all commonly implicated in the development of gastropar- esis. The aims of our study were to investigate whether exogenous sex hormone supplementa- tion restores impaired nuclear factor erythroid 2-related factor 2 (Nrf2, an oxidative stress- responsive transcription factor) and NO-mediated gastric motility in ovariectomized (OVX) female mice consuming a high-fat diet (HFD) to induce T2DM. Methods: Young adult (12 wk old) C57BL/6J (n=46) female mice were separated into sham and ovariectomized (OVX) groups and fed either with a standard chow diet (ND) or HFD for 12 weeks. Groups of OVX+HFD mice were administered daily subcutaneous doses of either 17b-estradiol (E 2 ) (0.25 mg/kg/bw or 1.0 mg/kg/bw) or progesterone (P 4 ) (2.0 mg/kg or 4.0 mg/kg/bw) for S-623 AGA Abstracts the duration of the 12-week study. The effects of OVX and HFD on metabolic homeostasis, solid GE, gastric non-adrenergic, non-cholinergic (NANC) -mediated relaxation, systemic hormone and total nitrite levels, and neuronal nitric oxide synthase (nNOS α) and its cofactor synthesis proteins levels were assessed. In addition, changes in pro-inflammatory cytokines, Nrf2, and MAPK, a master intracellular regulator, protein inductions were evaluated. Histo- pathological alterations in gastric specimens were also noted. Results: First, we demonstrate that Obesity (Sham + HFD) and chronic loss of hormones (OVX+ND) significantly (p<0.05) increased metabolic parameters (body weights, glycemia and insulinemia), while delaying GE and impairing nitrergic function when compared to ND-fed sham mice (p<0.05). Interest- ingly, the combination of OVX and HFD exacerbates hyperglycemia and insulinemia, while accelerating GE (p<0.05) though nitrergic relaxation was impaired. Exogenous E 2 , but not P 4 , attenuated rapid GE and diminished nitrergic relaxation while elevating total nitrite levels in OVX+HFD mice. E 2 significantly (p<0.05) restored impaired nNOS α, guanine triphosphate cyclohydrolase (GCH-1), and MAPK protein expression in OVX+HFD gastric tissues. Conclusions: Our findings demonstrate potential molecular underpinnings of sex hormone influence on Nrf2 and nNOS function in GE in female mice. Su1728 GASTROINTESTINAL SYMPTOMS DURING GASTRIC EMPTYING SCINTIGRAPHY CORRELATE WITH PERCENT RETENTION AND DIFFER BETWEEN CHILDREN WITH AND WITHOUT GASTROPARESIS Liz Febo-Rodriguez, Bruno P. Chumpitazi, Salma Musaad, Andrew Sher, Robert J. Shulman Background: Previous studies in children and adults have not demonstrated a relationship between percent retention measured by gastric emptying scintigraphy ( GES) and dyspeptic symptoms (abdominal pain, chest burning, nausea, bloating, fullness, and/or vomiting). In these studies symptoms were identified using retrospective questionnaires. However, whether symptoms recorded prospectively during GES relate to the degree of gastric retention remains unclear. Aims: To ascertain prospectively dyspeptic symptoms, their severity and time course of appearance in children undergoing GES. We hypothesized that: 1) the severity of dyspeptic symptoms correlates with percent retention during GES and 2) the severity and time course of appearance of symptoms during GES differs between those children ultimately found to have gastroparesis ( GP) as defined by gastric retention > 60 at 2 hours and/or >10% at 4 hours (PMID: 18028513) versus those with normal gastric emptying. Methods: In an ongoing prospective study, children 5-18 years of age undergoing a 4-hour solid (Tougas) meal GES study complete a symptoms questionnaire via REDCap. Dyspeptic symptoms (abdominal pain, chest burning, nausea, bloating, fullness) are each recorded at baseline (prior to meal ingestion), during meal ingestion, and at 15, 30, 45, 60, 120, 180, and 240 min. following the meal. Each symptom’s severity is rated 0-100 on a visual analogue scale. Total symptom score is the sum of the individual scores. Statistical analyses included regression modeling and non-parametric Wilcoxon 2-sample testing. Results: To date, 104 children have been studied. A total of 52 children (50%) had GP (GP: 12.5 ± 2.9 years [mean±SD], 65% female; non-GP: 13.0 +/- 2.9 years [mean±SD], 60% female). When evaluating the entire cohort together, only bloating correlated with percent retention and it did so at every hour (1 hr., P=0.01; 2 hrs., P =0.004; 3 hrs., P =0.02; 4 hrs., P =0.03). Nausea was the only symptom to correlate with the degree of retention (at the fourth hour) in subjects with GP (Table). Fullness correlated with the degree of retention at the second and third hours in subjects with normal emptying (Table). Total symptom score did not differ between those with GP vs normal emptying. However, bloating was significantly worse over the entire test period in those with GP vs normal emptying (P=0.05). Conclusions: During GES in children, bloating correlates with the severity of gastric retention. Bloating symptoms are worse in those with GP vs normal stomach emptying over the time course of GES. Symptoms of bloating, fullness, and nausea may help differentiate those children with GP vs those with normal gastric emptying. Su1729 PILOTING A PROSPECTIVE PEDIATRIC GASTROPARESIS SYMPTOM QUESTIONNAIRE Liz Febo-Rodriguez, Bruno P. Chumpitazi, Salma Musaad, Andrew Sher, Robert J. Shulman Background: The Gastroparesis Cardinal Symptoms Index ( GCSI) has been validated for use in adults and has been used for years to measure adult gastroparesis ( GP) severity and study outcomes. However, currently there is no validated prospective pediatric GP patient- reported symptoms instrument to assess the severity of pediatric GP. There is a critical need for such a tool to provide a reliable means to follow disease outcomes and responses to changes in management. Aims: To begin to develop and assess the reliability of a prospective pediatric GP-specific symptoms questionnaire. Methods: By using the GCSI as a base model, a pediatric cardinal symptoms questionnaire was developed. The measured symptoms included: abdominal pain, chest burning, nausea, bloating, fullness, and hunger. Each AGA Abstracts