Microvette 500 k3 edta coated capillary tubes

To compare levels of 3-hydroxydecanoate in CONV-R Swiss Webster mice fed a chow or HFD, male mice of 10–11 weeks of age (N = 6 mice/group) were fed a standard chow diet or HFD (research Diets #D12492i) with 60% energy from fat for two weeks. The mice were then fasted for 4 h, anesthetized using isoflurane (Baxter #EAAG9623C) and blood was collected from vena cava into Microvette® 500 K3 EDTA-coated capillary tubes (Sarstedt #20.1341). Plasma was separated after centrifugation (10,000xg for 5 min), snap-frozen and stored at −80°C until metabolomics analysis. Epididymal fat pads and the liver were harvested and snap-frozen in liquid nitrogen for metabolomics analysis.

Male CONV-R Swiss Webster mice of 12 weeks of age were fasted for 4 h, weighed and randomized in a weight-matched manner into two groups (N = 6 mice/group). In the morning, mice were injected i.p. with 25 mg/kg 3-hydroxydecanoate (Larodan #14–1003) dissolved in 5% v/v DMSO (Sigma #D5879) in 0.9% saline (Mediq Danmark #B230553) for seven days. The vehicle group received 5% v/v DMSO in saline. Based on the 3-hydroxydecanoate (or vehicle) stock solution, the dosing volume was 5.32 μL/g body weight, resulting in a dose of 0.29 mg/g body weight DMSO. On day eight, the mice were fasted for 4 h, anesthetized with isoflurane (Baxter #EAAG9623C), and the vena cava blood was collected into Microvette® 500 K3 EDTA-coated capillary tubes (Sarstedt #20.1341). Blood samples were centrifuged (10,000xg for 5 min) and separated plasma was snap-frozen and stored at −80°C until cytokine measurements. Epididymal and inguinal fat pads and the liver were harvested and snap-frozen in liquid nitrogen for RNA isolation. In addition, the epididymal and inguinal fat pads and liver were harvested, placed in the cassettes and stored in 4% formaldehyde (VWR #9713.5000) for two days before embedding in paraffin.