The Uptake and Deconjugation of Androstenone Sulfate in the Adipose Tissue of the Boar

Abstract

Boars express high testicular levels of sulfotransferase enzymes, and consequently, the boar taint causing compound androstenone predominantly circulates as a steroid sulfate. Androstenone sulfate is suspected to function as a steroid reservoir that can be deconjugated to provide a source of free androstenone for accumulation. Therefore, the purpose of this study was to characterize the uptake and deconjugation of androstenone sulfate in the adipose tissue of the boar. Real-time PCR was used to quantify the expression of steroid sulfatase (STS) and several organic anion transporting polypeptides (OATPs) in the adipose tissue. Additionally, [3H]-androstenone sulfate was incubated with adipocytes or supernatant from homogenized fat to assess steroid uptake and conversion, respectively. A positive correlation existed between OATP-B expression and androstenone sulfate uptake (r = 0.86, p = 0.03), as well as between STS expression and androstenone sulfate conversion (r = 0.76, p < 0.001). Moreover, fat androstenone concentrations were positively correlated (r = 0.85, p < 0.001) with androstenone sulfate conversion and tended to increase with STS expression in early maturing boars. This suggests that androstenone sulfate uptake and deconjugation are mediated by OATP-B and STS, respectively, which may influence the development of boar taint in early maturing animals.

The Effect of the Boar Taint Masking Strategy (Adding Dried Origanum vulgare or Allium sativum) on Sensory Characteristics

“…No significant differences in skatole levels or in the sensory perception of the panellists were detected between the individual muscles. According to more recent studies [ 9 , 32 ], the level of boar taint components in fat, lean tissue and plasma may be affected by the presence of other compounds related to boar taint. One of these compounds is androstenone sulphate, which contributes significantly to the free androstenone content in tissues.…”

Can sensory boar taint levels be explained by fatty acid composition and emitted volatile organic compounds in addition to androstenone and skatole content?

“…leading to a poorer correlation). Such conjugates include androstenone sulfates such as androst-3-enol-3-sulfate and androstenone-4-sulfate (Bone & Squires, 2021;Squires et al, 2020). Secondly, correlation is lower at higher levels of androstenone than at lower ones.…”

Nuclear Receptor Pathways Mediating the Development of Boar Taint

“…This suggests that the sulfoconjugation of androstenone and its metabolites during Phase II metabolism is essential for reducing the development of boar taint. However, we have recently shown that androstenone sulfate can be transported into the adipose tissue and deconjugated by the enzyme steroid sulfatase (STS) [61]. The deconjugation of androstenone sulfate was positively correlated with fat androstenone concentrations in early but not late-maturing boars, which suggests that the sulfoconjugation of the 16-androstene steroids may not reduce boar taint development in all animals.…”