Possible Interaction: Adenosine and Pentoxifylline

“Kreth et al. suggest that the anti-inflammatory properties of PTX are mediated by adenosine , more specifically via the adenosine A2A receptor (A2AR) pathway.”

“In T cells, adenosine plus PTX revealed similar synergistic inhibitory effects on proinflammatory cytokine production.”

“In stimulated … leukocytes, PTX treatment led to a 4.5-fold … of the 50% inhibitory concentrations of adenosine on the H2O2 production; i.e., for adenosine plus PTX (in clinically relevant concentrations), an overadditive … of inhibitory effects from less than 20% (estimated for each) to 56% (±5%) was found.”

“Thus for TNF alpha-primed PMN, pentoxifylline decreases PMN activity by enhancing the effect of adenosine on degranulation and superoxide production; whereas caffeine increases PMN activity by counteracting the effect of adenosine on degranulation.”

“For instance, pentoxifylline potentiates the anti-inflammatory actions of adenosine , prostacyclin, and prostaglandins of the E series by its synergistic action on intracellular cyclic AMP.”

“An inhibition of the erythrocyte uptake of adenosine contributes to the antiaggregatory effect of pentoxifylline.”

“These results reflect differences between the sites of action of ADO and POF.”

“ Pentoxifylline inhibited ingestion of microbial particles (Staphylococcus aureus and zymosan); decreased superoxide generation activated by zymosan, formyl-methionyl-leucyl-phenylalanine, and concanavalin A (but not phorbol myristate acetate); and decreased uptake (transport) of adenosine stimulated by formyl-methionyl-leucyl-phenylalanine and zymosan.”

“ PTX abolished contraction induced by adenosine or R-PIA, implying that contraction activated by A1 receptor was coupled to a pertussis toxin (PTX)-sensitive G(i) protein.”

“Treatment with PTX completely abolished the effect of both ATP and adenosine on atrial action potential duration.”

“In the isolated atrium, aminophylline, but not pentoxifylline , significantly inhibited the negative chronotropic and inotropic effects of adenosine.”