L-cysteine and zinc L-carnosine in the therapy of chronic atrophic gastritis: clinical efficacy and tolerability
Keywords:
chronic atrophic gastritis, L-cysteine, zinc L-carnosine, pepsinogen I , gastrin 17, OLGAAbstract
Background and aim: Chronic atrophic gastritis (CAG) is characterized by gastric atrophy due to loss of the mucosa cells. Clinical manifestations are represented by gastrointestinal symptoms and/or alterations due to macronutrient deficiency. There is no specific therapy for CAG, although some medical devices appear promising: L-cysteine reduces acetaldehyde levels in the stomach , zinc L-carnosine shows direct cytoprotective and anti-inflammatory action. We evaluated, in CAG patients, the therapeutic efficacy and tolerability of both devices on the improvement of gastric functional picture and symptoms as compared to a control group. Methods: 200 CAG patients were recruited and divided into: Group 1: L-cysteine 300 mg/daily; Group 2: zinc L-carnosine 75 mg/daily; Group 3: control group without any therapy. Patients were followed up for three months to evaluate the efficacy of both molecules and the possible appearance of side effects and adverse events. Results: Increased serum pepsinogen l (efficacy rate 37.1% and 21.3%) and decreased gastrin 17 levels (efficacy rate 41.3% and 58.7%) were found for L-cysteine and zinc L-carnosine, respectively. An improvement or no appearance of new symptoms was detected (65.7% for L-cysteine and 77.3% for zinc L-carnosine). Both devices appeared well tolerated (compliance rate of 100% for L-cysteine and 93.7% for zinc L-carnosine) and side effects were limited to manifestations that resolved after stopping therapy. Conclusions: Clinical efficacy of both molecules on CAG patients management represents a promising result; however, further randomized prospective studies performed on larger series for a prolonged time and on individual pathology groups are mandatory to confirm these data.
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