Baicalin Is Curative Against Rotavirus Damp Heat Diarrhea by Tuning Colonic Mucosal Barrier and Lung Immune Function

Dig Dis Sci. 2020 Aug;65(8):2234-2245. doi: 10.1007/s10620-019-05977-w. Epub 2019 Dec 4.

Abstract

Background: Previous studies have indicated that rotavirus (RV) is a causative factor for diarrhea and gastroenteritis in pediatric and neonatal settings. Baicalin has many functions, including antibacterial, antiinflammatory, and antihypertensive activities. However, the immunological mechanism of RV-induced diarrhea with heat-dampness syndrome (RV-DH) remains unclear.

Aims: The aim of this study is to explore the role of baicalin in RV-DH diarrhea and its underlying mechanism.

Methods: A mouse model of pediatric RV-DH diarrhea was established and treated with baicalin. The concentrations of cytokines were detected by enzyme-linked immunosorbent assay. Messenger RNA (mRNA) expression levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR), while protein expression levels were determined by Western blotting and immunohistochemistry. Flow cytometry was used to detect the frequency of lymphocytes.

Results: The concentrations of interleukin-1β (IL-1β), IL-2, IL-6, IL-8, RVvb, and secretory immunoglobulin A (SIgA) in bronchoalveolar lavage fluid (BALF) and colonic mucosa were significantly increased in the RV-DH group. Decreased expression of occludin, claudin-1, and zonula occludens-1 (ZO-1) indicated loss of tight junction function and disturbances in intestinal mucosal permeability in the RV-DH group. Flow cytometry analysis showed a high rate of CD8+ lymphocytes and low amount of CD4+ lymphocytes in the RV-DH group. Treatment of RV-DH mice with baicalin significantly reduced the duration of diarrhea and ameliorated the symptoms and pathological and immunological changes. Furthermore, baicalin inhibited STAT1 and activated STAT3 signaling pathways.

Conclusions: These findings indicate the curative and immunoregulatory properties of baicalin and have direct practical and clinical relevance for the treatment of RV-DH enteritis in humans.

Keywords: Baicalin; Cytokines; Heat-dampness syndrome; Rotavirus diarrhea.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Colon / drug effects
  • Colon / metabolism
  • Diarrhea / drug therapy*
  • Diarrhea / etiology
  • Disease Models, Animal
  • Drug Evaluation, Preclinical
  • Drugs, Chinese Herbal / pharmacology
  • Drugs, Chinese Herbal / therapeutic use*
  • Flavonoids / pharmacology
  • Flavonoids / therapeutic use*
  • Intestinal Mucosa / drug effects*
  • Intestinal Mucosa / immunology
  • Lung / drug effects*
  • Lung / immunology
  • Medicine, Chinese Traditional
  • Mice, Inbred BALB C
  • Rotavirus Infections / complications
  • STAT1 Transcription Factor / metabolism
  • STAT3 Transcription Factor / metabolism

Substances

  • Drugs, Chinese Herbal
  • Flavonoids
  • STAT1 Transcription Factor
  • STAT3 Transcription Factor
  • Stat1 protein, mouse
  • Stat3 protein, mouse
  • baicalin