Barrett's Esophagus and β-carotene Therapy: Symptomatic Improvement in GERD and Enhanced HSP70 Expression in Esophageal Mucosa

Abstract

Epidemiological studies suggest a protective role for β-carotene with several malignancies. Esophageal adenocarcinoma frequently arises from Barrett's esophagus (BE). We postulated that β-carotene therapy maybe protective in BE. We conducted a prospective study in which 25 mg of β-carotene was administered daily for six-months to six patients. Each patient underwent upper endoscopy before and after therapy and multiple mucosal biopsies were obtained. Additionally, patients completed a gastroesophageal reflux disease (GERD) symptoms questionnaire before and after therapy and severity score was calculated. To study the effect of β-carotene at molecular level, tissue extracts of the esophageal mucosal biopsy were subjected to assessment of heat-shock protein 70 (HSP70). A significant (p<0.05) reduction in mean GERD symptoms severity score from 7.0±2.4 to 2.7±1.7 following β-carotene therapy was noted. Measurement of Barrett's segment also revealed a significant reduction in mean length after therapy. In fact, two patients had complete disappearance of intestinal metaplasia. Furthermore, marked enhancement of HSP70 expression was demonstrated in biopsy specimens from Barrett's epithelium in four cases that were tested. Long- term β-carotene therapy realizes amelioration of GERD symptoms along with restitution of the histological and molecular changes in esophageal mucosa of patients with BE, associated with concurrent increase in mucosal HSP70 expression.