Effect of cocoa-enriched diets on lymphocytes involved in adjuvant arthritis in rats.

Abstract

Cocoa and its flavonoids have potential anti-inflammatory properties in vitro and in acute inflammation models in vivo. The aim of the present study was to ascertain the effects of two cocoa-enriched diets on adjuvant arthritis (AA) in rats, considering not only clinical and biochemical inflammatory indices, but also antibody response and lymphocyte composition. Female Wistar rats were fed with a 5 or 10 % cocoa-enriched diet beginning 2 weeks before arthritis induction and until the end of the study. AA was induced by an intradermal injection of heat-killed Mycobacterium butyricum suspension. The hind-paw swelling (plethysmometry), serum anti-mycobacterial antibody concentration (ELISA), blood and inguinal lymph node lymphocyte subset percentage (flow cytometry), and IL-2, interferon γ and PGE₂ released from splenocytes (ELISA) were assessed. Although the cocoa diets had no significant effect on hind-paw swelling, a tendency to reduce it was observed at the end of the study. Cocoa-enriched diets were able to decrease the serum anti-mycobacterial antibody concentration and the splenocyte PGE2 production, as well as the proportion of T-helper (Th) lymphocytes in blood and regional lymph nodes, which probably includes cells responsible for the arthritic process. The cocoa diets prevented a decrease in the proportion of regulatory T-cells in blood and a disequilibrium between inguinal lymph node natural killer (NK) CD8⁺ and NK CD8⁻ subsets. In conclusion, the cocoa-enriched diets during AA were not able to significantly decrease joint inflammation but modified Th-cell proportions and prevented specific antibody synthesis.

• Authors: Sara Ramos-Romero, Francisco J Pérez-Cano, Cristina Castellote, Margarida Castell, Àngels Franch
• Journal: The British journal of nutrition (Br J Nutr) Vol. 107 Issue 3 Pg. 378-87 (Feb 2012) ISSN: 1475-2662 [Electronic] England
• PMID: 21762542 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Anti-Inflammatory Agents, Non-Steroidal
• Antibodies, Bacterial
• Flavonoids
• Dinoprostone

Topics

• Animals
• Anti-Inflammatory Agents, Non-Steroidal (administration & dosage, analysis, therapeutic use)
• Antibodies, Bacterial (analysis)
• Arthritis, Experimental (immunology, metabolism, pathology, prevention & control)
• Cacao (chemistry)
• Cells, Cultured
• Diet
• Dinoprostone (metabolism)
• Female
• Flavonoids (administration & dosage, analysis, therapeutic use)
• Killer Cells, Natural (immunology, metabolism, pathology)
• Lymph Nodes (cytology, immunology, pathology)
• Lymphocyte Count
• Lymphocytes (immunology, metabolism, pathology)
• Mycobacterium (immunology)
• Random Allocation
• Rats
• Rats, Wistar
• Spleen (immunology, metabolism, pathology)
• T-Lymphocyte Subsets (immunology, metabolism, pathology)