Hesperidin inhibits inflammatory response induced by Aeromonas hydrophila infection and alters CD4+/CD8+ T cell ratio

Abstract

Background: Aeromonas hydrophila is an opportunistic bacterial pathogen that is associated with a number of human diseases. Hesperidin (HES) has been reported to exert antioxidant and anti-inflammatory activities.

Objectives: The aim of this study was to investigate the potential effect of HES treatment on inflammatory response induced by A. hydrophila infection in murine.

Methods: A. hydrophila-infected mice were treated with HES at 250 mg/kg b.wt./week for 4 consecutive weeks. Phagocytosis, reactive oxygen species production, CD4(+)/CD8(+) T cell ratio, and CD14 expression on intestinal infiltrating monocytes were evaluated. The expression of E-selectin and intercellular adhesion molecule 1 on stimulated HUVECs and RAW macrophage was evaluated.

Results: Percentage of CD4(+) T cells in the intestinal tissues of infected treated mice was highly significantly increased; however, phagocytic index, ROS production, CD8(+) T cells percentage, and CD14 expression on monocytes were significantly reduced. On the other hand, HES significantly inhibited A-LPS- and A-ECP-induced E-selectin and ICAM-1 expression on HUVECs and ICAM-1 expression on RAW macrophage.

Conclusion: Present data indicated that HES has a potential role in the suppression of inflammatory response induced by A. hydrophila toxins through downmodulation of ROS production and CD14 and adhesion molecules expression, as well as increase of CD4(+)/CD8(+) cell ratio.

Figure 1

In vivo effect of hesperidin inoculation on body weight (a), liver weight/g (b), spleen weight/g (c), and intestine weight/g (d). Mice were infected, each with 2 × 10⁸ CFU of Aeromonas hydrophila per week for four consecutive weeks (B-infected group), and treated simultaneously with hesperidin at a dose of 250 mg/kg/week for four consecutive weeks (HES-treated group). At the end of week 4 following exposure and treatment, mice were sacrificed and weighted, the liver, spleen, and intestine were weighted, phagocytic activity was estimated in fresh blood, and intestinal ROS production was evaluated in intestinal homogenate. Values not sharing common superscripts denote significant differences.

Figure 2

In vivo effect of hesperidin inoculation on phagocytic activities in blood (NBT index) (a) and intestinal reactive oxygen species (ROS) production (b). Mice were infected, each with 2 × 10⁸ CFU of Aeromonas hydrophila per week for four consecutive weeks (B-infected group), and treated simultaneously with hesperidin at a dose of 250 mg/kg/week for four consecutive weeks (HES-treated group). At the end of week 4 following exposure and treatment, mice were sacrificed and weighted, the liver, spleen, and intestine were weighted, phagocytic activity was estimated in fresh blood, and intestinal ROS production was evaluated in intestinal homogenate. Values not sharing common superscripts denote significant differences.

Figure 3

Representative dot plots of FACS analysis showing changes in Mean Fluorescence Index (MFI) of CD3⁺, CD4⁺, and CD8⁺ lymphocytes and CD14⁺ monocytes in intestinal infiltrating cells in different groups control group (C); bacteria-infected group (B); and bacteria treated with hesperidin group (HES-treated group). Data reported as Mean Fluorescence Index (MFI) ± standard deviation (SD). Values of the same parameter not sharing common superscripts denote significant differences.