Article Figures & Data
Figures
- FIGURE 1.
Schematic diagram of TBR system integrated with microPET Focus F220. (A) Cell chamber is integrated with microPET Focus F220 scanner in series with sensor probes, gas exchanger, degas vessel, and peristaltic pump. (B) Detailed schematic of cell chamber. C = carbon dioxide; DO/TMP = combined dissolved O2 and temperature probe; MFC = mass flow controllers; N = nitrogen; O = oxygen; S = septa.
- FIGURE 2.
Metabolic parameters during TBR study. (A) Concentration of glucose in feed, effluent (left axis), and consumption rate (right axis). (B) Concentration of FFA in feed, effluent (left axis), and production rate (right axis). (C) Concentration of lactate in feed, effluent (left axis), and production rate (right axis). Glucose, lactate, and FFA rate were calculated from piecewise function fitted curves. Refer to Table 1 for description of time stamps. Operational parameters throughout experiment: feed flow rate (Qfeed) = 0.5 mL/min, media recycle flow rate (Qrcy) = 50 mL/min, oxygen partial pressure (pO2) = 21%, pH set point = 7.3, and temperature = 37°C.
- FIGURE 3.
Physiologic parameters during TBR study. (A) DO and oxygen partial pressures (pO2) (left axis) and O2 consumption rate (right axis). (B) pH (left axis) and CO2 partial pressure (pCO2) needed to maintain pH (right axis). Operational parameters throughout experiment: feed flow rate (Qfeed) = 0.5 mL/min, media recycle flow rate (Qrcy) = 50 mL/min, pO2 = 21%, pH set point = 7.3, and temperature = 37°C.
- FIGURE 4.
(A) AUCs for 3 glucose uptake tests. Glucose concentration before bolus injection was used as baseline for integration. AUC represents integral between time of glucose injection, which is defined as baseline, to time when concentration returns to baseline in Figure 2. (B) Intercellular FFA and TG content of cell samples taken from chamber. Open symbols were sampled from upper septum; closed symbols were sampled from lower septum. Averages and SD represent data from multiple sampling of chamber at given location in time. Glu = glucose; PGZ = pioglitazone.
- FIGURE 5.
Coronal and sagittal views of TBR highlighting heterogeneity within chamber. Arrows indicate direction of flow from top of chamber to bottom. Max = maximum.
- FIGURE 6.
Representation of input function curve (A) in absence of cells in chamber (solid line) depicting transient kinetics and in presence of HepG2 cells with sampled obtained manually from inlet to chamber (•), effluent (■), and image (◆). (B) Kinetics of 2 regions of interest depicting heterogeneity of 11C-palmitate uptake in TBR chamber as shown in Figure 5. SUV = standardized uptake value.
- FIGURE 7.
Serum and TBR chamber 11C-palmitate kinetics in presence and absence of lipids. (A) Normalized standardized uptake value kinetics of 11C-palmitate in medium in presence and absence of lipids. (B) Region of interest drawn in TBR chamber depicting total uptake of 11C-palmitate in presence and absence of lipids. SUV = standardized uptake value.
Tables
Time stamp Time (h) Event A 17.2 Started medium feed, glucose = 5.55 mM B 119.9 Glucose = 1.39 mM C 137.9 Glucose uptake test 1, 0.75 mL bolus of 283 mg/mL D 162.1 Glucose = 5.55 mM, lipid = 100 μM E 236.8 Glucose = 1.39 mM, lipid = 100 μM F 258.1 Glucose uptake test 2, 0.75 mL bolus of 283 mg/mL G 286.3 Glucose = 5.55 mM, lipid = 100 μM, pioglitazone = 1 μg/mL H 334.9 Glucose = 1.39 mM, lipid = 100 μM, pioglitazone = 1 μg/mL I 358.5 Glucose uptake test 3, 0.75 mL bolus of 283 mg/mL 382.0 Glucose = 5.55 mM, pioglitazone = 0 520.0 First imaging* 643.0 Second imaging* ↵* Feed flow rate (Qfeed) = 5 mL/min during imaging sessions.
Operational parameters throughout experiment: Qfeed = 0.5 mL/min, media recycle flow rate (Qrcy) = 50 mL/min, pO2 = 21%, pH set point = 7.3, temperature = 37°C.
Supplemental Data
Files in this Data Supplement:
