Assessment of the Antioxidant/Hypolipidemic Relationship of Sideritis hyssopifolia in an Experimental Animal Model.

Many publications have described the potential cardioprotective action of different medicinal plants, relating this effect with blood lipid levels. However, these publications do not justify the right amount of plant administered, which can vary greatly. Sideritis hyssopifolia is a little woody plant endemic to western and southwestern Europe. We have quantified its antioxidant activity, which can be used as an indicator of its cardioprotective action. This study evaluates the antioxidant capacity of Sideritis hyssopifolia to design a feed whose hypolipidemic effects are proven in cholesterol-fed New Zealand rabbits. Antioxidant action was assessed in infusions, which were prepared with 1 or 3 g of plant in 200 mL of water by using an ABTS assay and expressed as Ascorbic acid Equivalent Antioxidant Capacity (AEAC). Aqueous infusions with infusion times of 10 min and prepared with 3 g plant exhibited the strongest antioxidant activity. Sideritis hyssopifolia showed an intermediate antioxidant capacity for the concentrations and times of the infusion tested. According to our results, we suggest incorporating 2.36 g of S. hyssopifolia every 150 g of rabbit feeding stuff (15.73 g/kg). This chow decreased cholesterol, HDL-cholesterol, LDL-cholesterol, and triglycerides levels in cholesterol-fed rabbits, as well as the atherogenic index. This reduction was similar to that obtained with simvastatin.

Systemic and mammary gland disposition of enrofloxacin in healthy sheep following intramammary administration.

BACKGROUND: Mastitis is one of the most important diseases affecting dairy sheep. Antimicrobial drugs are often administered directly through teat to treat or prevent this disease, but data on drug distribution within glandular tissue are scarce and it cannot be estimated from concentrations in milk. Thus, the aim of this study was to investigate systemic and mammary gland distribution of enrofloxacin after intramammary administration. The drug was administered to 6 healthy lactating Assaf sheep with an injector containing an enrofloxacin preparation (1 g drug/5 g ointment). Blood samples were collected at 0, 30, 60, 90, 120, 150 and 180 min. Animals were then sedated and sacrificed, and glandular tissue samples were obtained from treated udders at 2, 4, 6 and 8 cm height. Enrofloxacin concentrations were measured in plasma and tissue samples by UV high-performed liquid chromatography. RESULTS: Mean enrofloxacin plasma concentrations were below 0.5 µg/mL. Mean tissue concentrations decreased in mammary gland with vertical distance from the teat, ranging from 356.6 µg/g at 2 cm to 95.60 µg/g at the base of the udder. Glandular tissue concentrations best fitted to a decreasing monoexponential model, and showed a good correlation with an ex vivo model previously developed. CONCLUSIONS: Enrofloxacin concentrations were effective in the entire glandular tissue against the main pathogens causing mastitis in sheep. These results suggest that this drug may be suitable to treat mastitis in sheep by intramammary administration.