Salicylic Acid sans Aspirin in Animals and Man: Persistence in Fasting and Biosynthesis from Benzoic Acid

Abstract

Salicylic acid (SA), which is central to defense mechanisms in plants and the principal metabolite of aspirin, occurs naturally in man with higher levels of SA and its urinary metabolite salicyluric acid (SU) in vegetarians overlapping with levels in patients on low-dose aspirin regimens. SA is widely distributed in animal blood. Fasting for major colorectal surgery did not cause disappearance of SA from plasma, even in patients following total proctocolectomy. A 13C6 benzoic acid load ingested by six volunteers led, between 8 and 16 h, to a median 33.9% labeling of urinary salicyluric acid. The overall contribution of benzoic acid (and its salts) to the turnover of circulating SA thus requires further assessment. However, that SA appears to be, at least partially, an endogenous compound should lead to reassessment of its role in human (and animal) pathophysiology.

Benzoate- and Salicylate-Tolerant Strains of Escherichia coli K-12 Lose Antibiotic Resistance during Laboratory Evolution

“…Some permeant acids also cross the membrane in the unprotonated form and decrease the proton motive force (PMF); an example is benzoic acid (benzoate), a food preservative found in soft drinks and acidic foods (12). The related molecule salicylic acid (salicylate) is a plant defense regulator (13,14) as well as the primary active metabolite of acetylsalicylate (aspirin) (15)(16)(17). Salicylates enter the human diet from fruits and vegetables, leading to circulating plasma levels as high as 0.1 to 0.2 M (18).…”

Non-Steroidal Anti-Inflammatory Drugs, DNA Repair and Cancer

“…To facilitate interpretation, we have incorporated the concentrations utilised in the relevant publications. We should also point out that whilst vegetables and fruits have been considered to be a www.intechopen.com natural source of salicylate, where it functions as a plant signalling molecule (Paterson & Lawrence, 2001;Schenk et al, 2000, and refs therein), it has been reported that SA may be an endogenous compound, with SA found in the blood of carnivorous animals, for example in the burrowing owl (Paterson et al, 1998;Paterson et al 2008). Fig.…”

Robust and sensitive LC/MS-MS method for simultaneous detection of acetylsalicylic acid and salicylic acid in human plasma

“…ii) Complete separation of the analytes is essential, because ASP undergoes source fragmentation in the mass spectrometer and forms SAL. iii) In addition, highly different calibration ranges are required for ASP and SAL because of the endogenous SAL levels in blank human plasma [28,29]. iv) In the case of partial separation of the analytes, the much higher SAL levels can lead to ion suppression in the source of the mass spectrometer.…”