Prolonged Fasting Induces Histological and Ultrastructural Changes in the Intestinal Mucosa That May Reduce Absorption and Revert after Enteral Refeeding

Gonçalo Nunes; Marta Guimarães; Hélder Coelho; Ricardo Carregosa; Cátia Oliveira; Sofia S Pereira; António Alves de Matos; Jorge Fonseca

doi:10.3390/nu16010128

Prolonged Fasting Induces Histological and Ultrastructural Changes in the Intestinal Mucosa That May Reduce Absorption and Revert after Enteral Refeeding

Nutrients. 2023 Dec 30;16(1):128. doi: 10.3390/nu16010128.

Authors

Gonçalo Nunes^{1

2

3}, Marta Guimarães^{4

5}, Hélder Coelho⁶, Ricardo Carregosa⁷, Cátia Oliveira¹, Sofia S Pereira^{4

5}, António Alves de Matos⁷, Jorge Fonseca^{1

2

3}

Affiliations

¹ Gastroenterology Department, GENE-Artificial Feeding Team, Hospital Garcia de Orta, 2805-267 Almada, Portugal.
² ICBAS-UP-Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal.
³ PaMNEC-Grupo de Patologia Médica, Nutrição e Estudos Clínicos, Egas Moniz Center for Interdisciplinary Research (CiiEM), Egas Moniz School of Health and Science, 2829-511 Almada, Portugal.
⁴ UMIB-Unit for Multidisciplinary Research in Biomedicine, ICBAS-School of Medicine and Biomedical Sciences, Universidade do Porto, Rua Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal.
⁵ ITR-Laboratory of Integrative and Translocation Research in Population Health, Rua das Taipas 135, 4050-600 Porto, Portugal.
⁶ Pathology Department, Hospital Garcia de Orta, 2805-267 Almada, Portugal.
⁷ Cmicros-Centro de Microscopia Eletrónica e Histopatologia, CiiEM-Centro de Investigação Interdisciplinar Egas Moniz, 2829-511 Almada, Portugal.

Abstract

Background: Malnutrition is usual in patients referred for endoscopic gastrostomy (PEG). Refeeding syndrome is rarely observed in PEG-fed patients, which could possibly be associated with reduced absorption induced by prolonged starvation. Objective: In patients submitted to PEG after a significant period of fasting, the present study aims to: 1. evaluate the histological/ultrastructural initial changes in the intestinal mucosa, potentially associated with reduced absorption, and 2. assess if these changes could reverse with enteral refeeding. Methods: The present study is an observational, prospective, controlled study. Adult patients with ingestion below 50% of daily needs for at least one month and/or diagnosis of malnutrition were enrolled. Duodenal biopsies were taken at baseline and after 3-6 months of PEG feeding, which then underwent histological/ultrastructural analysis. Random healthy individuals were used as controls. Results: A total of 30 patients (16 men/14 women) aged 67.1 ± 13.5 years were included. Malnutrition was found in 40% of patients. Approximately 14 patients completed follow-up during both periods (46.7%). At baseline: duodenal mucosal atrophy was evident in three patients (10%); the median villi length (MVL) was 0.4 mm (0.25-0.6 mm), with it being shorter than the controls, which was 0.6 mm (0.4-0.7 mm) (p = 0.006); ultrastructural changes included focal shortening, bending, and disruption of enterocyte microvilli, the presence of citoplasmatic autophagic vacuoles, dilation and vesiculation of the smooth endoplasmic reticulum, and the presence of dilated intercellular spaces with basement membrane detachment. After refeeding, most patients displayed normal histology (92.9%) and increase MVL (p < 0.001), ultrastructural changes disappeared, and enterocytes resumed a normal appearance, although retaining scarce, small, dense bodies in apical regions from the evolution of previous autophagy. Conclusions: Prolonged fasting induces histological and ultrastructural changes in the intestinal mucosa that may reflect impaired absorption in the early post-PEG period. These changes were reverted after refeeding with enteral nutrition.

Keywords: PEG; duodenal mucosa; histology; malnutrition; ultrastructure.

Publication types

Controlled Clinical Trial
Observational Study

MeSH terms

Adult
Duodenum
Fasting*
Female
Humans
Intestinal Mucosa
Male
Malnutrition* / etiology
Prospective Studies

Grants and funding

This work was financed by national funds from the FCT—Foundation for Science and Technology, I.P., under the project UIDB/04585/2020. This work was also partially supported by a research grant obtained from the Portuguese Gastroenterology Society. The study sponsors were not involved in the study design, data collection, analysis of data, or interpretation of the data.