Coffee charcoal is described as the milled, roasted to blackening outer seed parts of green dried Coffea Arabica L. fruits and was introduced into medical practice by August G. Heisler in 1937. Within a traditional herbal medicinal product (Myrrhinil-Intest®) it is used for the treatment of intestinal disorders. Previous pharmacological studies revealed significant effects of a coffee charcoal extract on cytokine/chemokine signalling in human macrophages.
The present investigation aimed to identify potential active components in coffee charcoal and to test their effects on cytokine/chemokine release from activated THP-1 cells.
An HPLC/LC-MS method was developed and utilised to determine UV-detectable substances in an aqueous coffee charcoal extract. Their effect on cytokine (TNF α ; IL-6) and chemokine (MCP-1) release from LPS-challenged human macrophages (THP-1) was investigated using ELISA . Budesonide served as positive control and concomitant cytotoxicity testing was conducted via MTT assay.
HPLC/LC-MS analysis detected the presence of trigonelline, caffeine, chlorogenic acid (3-CQA) and its isomers cryptochlorogenic (4-CQA) and neochlorogenic acid (5-CQA) as well as feruloylquinic acid derivates in the coffee charcoal extract.
Cryptochlorogenic acid (4-CQA) led to an inhibition of cytokine TNFα (IC50=20.7µM) and IL-6 (IC50=43.3µM) as well as chemokine MCP-1 (IC50: 4-CQA=13.9µM) release. 3-CQA, 5-CQA and caffeine were less effective (3-CQA: IC50-TNFα=51.0µM; 5-CQA: IC50-TNFα=14.3µM; caffeine: IC50-TNFα=14µM; no influence on IL6 or MCP-1).
The present study revealed that pharmacologically active components in coffee charcoal affect cytokine and chemokine release from activated macrophages to a varying extent and thus contribute to the anti-inflammatory activity of the herbal substance. These data reinforce the use of coffee charcoal for the treatment of inflammatory intestinal disorders and suggests the application of 4-CQA as active marker for the anti-inflammatory activity.