Onetouch ultra2 glucometer

Freshly prepared alloxan monohydrate (Sigma, St. Loius, MO) was administered i.v. to both male and female F2 mice as well as male congenic mice through the tail vein at 6 weeks of age (Chen et al., 2008b (link)). All F2 mice in the GWS received the dose of 52 mg/kg. Congenic mice were subjected to a dose response where AL was administered at the escalating doses of 45 mg/kg, 50 mg/kg, or 55 mg/kg. Blood from non-fasted mice was drawn immediately prior to the injection of AL, and then at 7 and 14 days post-AL administration. Glucose levels were measured with a One Touch Ultra 2 glucometer (Life Scan, Milpitas, CA). Alloxan-induced diabetes (ALD) was diagnosed in mice with blood glucose of ≥ 250 mg/dl (Chen et al., 2008b (link)).

IGTT was performed after 4-week of exposure (SF 4w), following the 2-week recovery period (SF 2R), and in CTL. Mice were injected with glucose (2 mg/g body weight, i.p.) after 3 hours of fasting. Water was available during the fasting period. Blood glucose was measured using an OneTouch Ultra 2 glucometer (Life Scan; Milpitas, CA). Blood samples were collected from the tail vein at 0, 4, 15, 30, 60, 90 and 120 min. Glucose response during IGTT was evaluated by estimating the total area under the glycemia index vs. time curves.

Mice were injected intraperitoneally with humulin (0.25 U/kg of body weight) after 3 hours of fasting in both SF 4w, SF 2R, and CTL mice. Blood was collected via the tail vein from each mouse, and blood glucose was measured using an OneTouch Ultra2 glucometer (Life Scan; Milpitas, CA). Blood samples for insulin determination were obtained from the cut tip of the tail at 0, 4, 15, 30, 60 and 120 min following injection. Insulin resistance was assessed using the homeostasis model assessment (HOMA-IR) equation (fasting insulin × fasting glucose/22.5). ITT glycemic trajectories were also analyzed for differences in insulin sensitivity as previously described51 (link). Mice undergoing ITT were not assessed for IGTT and vice-versa.

Rats were weighed and housed in metabolic cages, and urine was collected for a period of 24 hours to determine osmolality (day 1). All rats were given tolvaptan to produce NDI (day 2). NDI was verified by measuring urine osmolality (days 3–4). NDI-5033(P1), suspended in HPMC, was given to half of the rats daily by gavage feeding beginning on day 4 at a dose of 10 mg/kg/day. Urine was collected each morning, and osmolality was determined. Exercise was initiated on day 12. Rats were fed normally overnight. The next morning, rats were given NDI-5033; the food was removed and withheld for 3 hours. Blood (about 10 μL) was collected by tail vein nick and tested for blood glucose levels using a One Touch Ultra 2 glucometer (LifeScan Inc.). Next, the rats were exercised for 30 minutes on a treadmill at a speed of 12 m/min with 1.5% inclination, consistent with other aerobic exercise treadmill studies in rats (24 (link), 25 (link)). Following the exercise, blood glucose levels were again determined, after which, food was restored. The same protocol was followed for 4 successive days.

Exercise capacity tests were carried out with the Exer 3/6 Rodent treadmill (Columbus Instrument, Columbus, OH). Prior to exercise capacity testing, the mice (12–15-week-old) were acclimated to the treadmill for three 10-min sessions on 3 consecutive days. The treadmill was set to 10° inclination and the speed was set to 0, 5, and 10 m/min for the first, second and third acclimation sessions, respectively. The electric shock grid at the rear end of the treadmill was turned on and set at stimulation intensity of 9 and frequency of 3 Hz. During exercise capacity testing, each mouse was placed into a lane of the treadmill. The genotype of the animals was blinded to the operator. The exercise protocol consisted of the following steps: (1) 10 m/min for 2 min for warm-up, (2) continuous acceleration from 15 m/min at a rate of 0.6 m/min² until the mouse was exhausted. Exhaustion was determined when the mouse stayed on the shock grid continuously for 5 s and was determined by the same observer for all experiments. Glucose and lactate were measured from a drop of blood from the tail tip before and immediately after exercise, using a OneTouch Ultra 2 glucometer (Lifescan, Inc) and a Lactate Plus lactate meter (Nova Biomedical), respectively.

All blood glucose measurements were obtained using a commercially available One-Touch^® Ultra^®2 Glucometer (LifeScan, Milpitas, CA, USA) using blood collected from the tail vein. The maximum glucometer reading was 600 mg/dL. Mice underwent body weight measurement and glucose tolerance testing after 3 months on the lean and HFHS diet to establish a chronic diabetic model. Mice were fasted overnight before the glucose tolerance test (GTT). Baseline fasting blood glucose levels were measured. An intraperitoneal injection of 20% glucose solution (Teknova Inc., Hollister, CA, USA; cat. number: G0530) was given, with a total glucose load of 2 g/kg. Blood glucose levels were measured at 15, 30, 60, and 120-min intervals following injection. Geometric areas under the curves (AUCs) were calculated for comparison of glucose tolerance. Mice underwent body weight, fasting blood glucose, and glucose tolerance testing after 6 months on the normal and HFHS diet.

Diabetes was induced in twelve rats by streptozotocin (Sigma-Aldrich Chemical Co., St. Louis, MO, USA; administered intraperitoneally at 60 mg/kg body weight) and monitored with a One Touch Ultra 2 Glucometer^® (Life scan Inc., Milpitas, CA, USA). Rats with a blood glucose ≥250 mg/dL 5 days after streptozotocin injection were used for the study. The weights were taken at the beginning and end (after 5 days) of the experiment using a laboratory scale (Sartorius, Goettingen, Germany).