A mass spectromeric study on meloxicam metabolism in horses and the fungus Cunninghamella elegans, and the relevance of this microbial system as a model of drug metabolism in the horse

• This paper describes a study where the metabolism of the non-steroidal   anti-inflammatory drug meloxicam was investigated in six horses and in  the filamentous fungus Cunninghamella elegans. The metabolites identified were compared between the species, and then the fungus was  used to produce larger amounts of the metabolites for future use as   reference material. C. elegans proved to be a good model of phase I   meloxicam metabolism in horses since all four metabolites found were   the same in both species. Apart from the two main metabolites,   5'-hydroxymethylmeloxicam and 5'-carboxymeloxicam, a second isomer of   hydroxymeloxicam and dihydroxylated meloxicam were detected for the   first time in horse urine and the microbial incubations. Phase II   metabolites were not discovered in the C. elegans samples but   hydroxymeloxicam glucuronide was detected intact in horse urine for the   first time in this study. Urine from six horses was further analyzed in   a semi-quantitative sense and 5'-hydroxymethylmeloxicam gave peaks with   much higher intensity compared to the parent drug and the other   metabolites, and was detected for at least 14 days after the last given   dose in some of the horses. From the results presented in this article,   we suggest that analytical methods developed for the detection of   meloxicam in horse urine after prohibited use should focus on the   5'-hydroxymethyl metabolite and that C. elegans can be used to produce  large amounts of this metabolite for potential future use as a reference compound.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Farmaceutiska vetenskaper (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Pharmaceutical Sciences (hsv//eng)

Keyword

Meloxicam

metabolism

mass spectrometry

horse

Cunninghamella elegans

PHARMACY

FARMACI

Analytical Pharmaceutical Chemistry

Analytisk farmaceutisk kemi

Publication and Content Type

ref (subject category)

art (subject category)