Freestyle freedom lite blood glucose monitoring system

Fasting blood glucose was measured with a FreeStyle Freedom Lite–blood glucose monitoring system (Abbott, Wiesbaden, Germany), directly after fish were sacrificed.

Eight-week-old female NOD/ShiLtJ (NOD) mice were purchased from the Jackson Laboratories (001976, The Jackson Laboratories, Bar Harbor, ME, USA) and used for this study, due to their higher incidence of T1D development as they age (50% of females compared to 30% of males by 22 weeks of age) [42 (link),43 (link),44 (link)]. Coxsackievirus B4 (CVB4) Edwards strain (GenBank: S76772.1) was used for this study (a generous gift from Roger Loria, Virginia Commonwealth University, Richmond, VA, USA). NOD mice were exposed at 10 weeks of age via intraperitoneal (IP) injection of 500,000 plaque-forming units (PFUs) of CVB4 or sterile phosphate-buffered saline (PBS) (#J373, VWR, Radnor, PA, USA) as a stress control. Body weight and blood glucose were measured once a week for the course of the study. A drop of blood was collected from the tip of the tail and applied to a handheld glucometer (Freestyle Freedom Lite Blood Glucose Monitoring System, Abbott Laboratories, Lake Bluff, IL, USA). Mice were considered to be diabetic with a non-fasting blood glucose level ≥ 250 mg/dL, and confirmed by glucosuria prior to euthanasia (#2806, Bayer Healthcare, Leverkusen, Germany).

Glucose, Nitrite and Phosphate concentrations were monitored during growth by electronic FreeStyle Freedom Lite® Blood Glucose Monitoring System (Abbott), Griess Reagent Kit for Nitrite Determination (Invitrogen) and EnzCheck® Phosphate Assay Kit (Invitrogen), respectively.
Polyphosphates (PPs) were extracted by an acid method and determined as in [18 (link)]. Nitrate amount was measured as described in [34 (link)]. The determination of the ammonium ion concentration was performed by a spectrophotometric method using Nessler’s reagent [35 (link)].