The Variation Of Leptin In Human Gastric Mucosa And Serum From Cases With Reflux Esophagitis

Objective: The morbidity of reflux esophagitis (RE) has been on the increase, but its pathogenesis is not yet very clear. At present, it is reported that transient lower esophageal sphincter relaxations (TLESR) and lower esophageal sphincter pressure (LESP) are considered as the main factors that can cause RE. And it is indicated that TLESR plays an important role in the pathogenesis of RE and delayed gastric emptying may trigger the course of TLESR. RE has been paid great attention. However, effective therapy of RE is still scarce. Recently it has been reported that a variety of gut hormones play an important role in the development of RE. Leptin, as a gut hormone, has been studied extensively. It has been proved that Leptin play a critical role in many fields including suppressing food intake, increasing energy consumption, regulating growth and development, immune function, and neuroendocrine. Moreover, Leptin has been studied further in gastric kinesis. Animal experiments have shown that Leptin can change gastric motility patterns, delay gastric emptying and regulate gastric movement combining with other gut hormones. However, there is no clinical research about the relationship between Leptin and RE. The aim of this study is to explore the role of Leptin in the development and pathogenesis of RE by detect the variation of Leptin in human gastric mucosa and serum from cases with reflux esophagitis in order to provide a new theoretical foundation for the pathogenesis of RE.Methods: In this study, case group including 20 male cases and 12 female cases were studied and their average age is 45.2 and average body mass index is 25.2 kg/m2. Control group including 9 male cases and 6 female cases without gastro-esophageal reflux symptoms and esophageal mucosal lesion under gastroscopic examination were selected as control group. The average age of the control group is 44.9 and the average body mass index (BMI) of the control group is 25.1 kg/m2. There was no statistical difference of the gender composition, average age, BMI between case group and control group. What's more, all the studied cases had no heart disease, diabetes, cirrhosis of the liver, renal insufficiency, primary hypertension, cerebrovascular disease, cancer, peptic ulcer, pyloric obstruction, chronic atrophic gastritis; all the studied cases had not been treated with non-steroidal anti-inflammatory drugs (NSAIDs) and glucocorticoids; all the studied cases had no drinking history. And the tests of helicobacter pylori (H. pylori) were negative by rapid urease test and serum antibody detection. The esophageal mucosa was observed by video gastroscopy firstly and all the RE group were further classified according to Los Angeles (LA) classification standards. A sample of biopsy was taken from gastric antral mucosa for rapid urease test, and the case would be excluded if the test result was positive. But another 2 pieces of sample were taken from lower greater curvature mucosa of corpus and fixed by 10% neutral formalin for paraffin sections. Fasting blood samples were collected for H.pylori antibody test and Leptin concentration determination. If the antibody test result was positive, the case would be excluded; while the blood sample would be used for further study, if the antibody test result was negative. The expression of Leptin was examined by immunohistochemistry and the semi-quantitative analysis of the staining was analyzed by the pathological image analysis system. The concentration of Leptin in the serum was determined by radioimmunoassay (RIA). All the data was shown as mean+standard deviation and analyzed by SPSS 12.0 software.Results: According to LA classification standard under gastroscopic examination, 10 cases in grade A, 15 cases in grade B and 7 cases in grade C, no one with grade D in 32 case group; while the esophageal mucosa was normal in all cases of control group.The Leptin level in the serum from the patients with RE was significantly higher than that from control group (6.79±1.54 ng/ml vs 4.78±1.69 ng/ml,P<0.05). But there was no significant difference of Leptin level in the serum from patients in LA A (1.91+0.95 ng/ml), LA B (1.39+1.09ng/ml),and LA C (1.07+0.74ng/ml).Immunohistochemical staining result showed that Leptin expressed in the lower half of basic glands of gastric corpus mucosa. There is no significant difference between the Leptin expression in patients with RE and that of control group (P>0.05). And the difference of Leptin expression in gastric corpus mucosa among grade A (412.86+48.42), grade B (388.89+45.56) and grade stage (375.81+56.11) was not remarkable (P>0.05).Conclusions: The Leptin level in the serum of case group increased compared with the control group, but it's not increased significantly with the aggravation of inflammation. The difference of the Leptin expression in corpus mucosa of case group and that of the control group was not significant, indicating that the Leptin expression may have no obvious effect in the RE. All the results suggested that the Leptin in the blood may play a role in the development of RE, but the Leptin expression in gastric mucosa had no obvious relation with RE.