Dietary Supplementation with Montmorency Tart Cherry Prevents the Alterations in Gut Mucosal Immunity That Occurs with Ovarian Hormone Deficiency

Postmenopausal women are at risk for a number of diseases linked to dysregulation of the immune response, including autoimmune diseases, osteoporosis and certain cancers. The decline in ovarian hormones that occurs with menopause is known to alter immune cell function and activation, but few studies have examined its specific effects on the gut mucosal immune response. Moreover, foods rich in phenolic compounds may provide a means of countering the effects of ovarian hormone deficiency due to their proximity to the gut mucosa and immunomodulating properties. Therefore, this study aimed to determine the alterations in the gut immune response induced by ovarian hormone deficiency and the extent to which dietary supplementation with dried tart cherries prevents this response. Five month old C57BL/6 female mice (n=10/group) were either sham‐operated (SHAM) or ovariectomized (OVX). OVX mice were then randomly assigned to treatments consisting of either control diet (OVX; AIN‐93M) or control diet supplemented with 5% (w/w) Montmorency cherry powder (CH; Van Drunen Farms); SHAM mice received the control diet. All diets were adjusted to have similar macronutrient, fiber, calcium and phosphorus content. Body weights were monitored throughout the study. At the end of the 28 day treatment period, a dual‐energy x‐ray absorptiometry scan was performed to assess body composition and the spleen, thymus, cecal contents and lamina propria (LP) from the colon were isolated. Body weight, lean mass and percent fat increased in the OVX group (P< 0.05) as expected, and cherry supplementation had no effect on this response. No differences were observed in cecal content and thymus weights among the groups. The OVX group experienced an increase (P< 0.05) in spleen weight, and cherry supplementation prevented this response to some extent (OVX=CH=SHAM). Following total RNA extraction from the LP, RT‐PCR was performed to assess the relative abundance of RNA for inflammatory mediators. Gene expression of interferon (IFN)‐γ was upregulated with OVX (P<0.05), and cherry supplementation restored IFN‐γ expression to that of the SHAM group. Tumor necrosis factor (TNF)‐α tended to be increased (P=0.0526) in the OVX group compared to the SHAM group, and cherry supplementation normalized this response. Additionally, the OVX‐induced suppression (P<0.05) of interleukin (IL)‐10, an anti‐inflammatory cytokine, was restored in CH group to that of the SHAM group. These data demonstrate that in a postmenopausal animal model, ovarian hormone deficiency promotes a pro‐inflammatory environment within the lamina propria of the colon and dietary supplementation with tart cherries provides a means of countering these responses.Support or Funding InformationCherry Research Committee of the Cherry Marketing Institute