Blockade of glucagon signaling prevents or reverses diabetes onset only if residual β-cells persist
- University of Geneva, Switzerland
- Eli Lilly and Company, United States
- Albert Einstein College of Medicine, United States
- Columbia University, United States
- Vanderbilt University, United States
- VA Tennessee Valley Healthcare System, United States
Figures
Figure 1 with 1 supplement
Gcgr-/- mice become diabetic after massive β-cell ablation.
(A) Random-fed glycemia (left) and area under the glycemia curve (AUC) between days 0 and 7 after DT (right) in untreated (Untr.) and DT-treated RIP-DTR;Gcgr+/- and RIP-DTR;Gcgr-/- females. (B) Body …
Figure 1—figure supplement 1
Insulin administration stabilizes body weight and allows survival of DT-treated Gcgr-/-mice.
Glycemia (left) and body weight (right) of RIP-DTR;Gcgr+/+ (blue triangles, N=7), RIP-DTR;Gcgr+/- (black squares, N=9), and RIP-DTR;Gcgr-/- (red circles, N=9) males following DT-mediated β-cell …
Figure 2 with 2 supplements
Anti-GCGR mAb-treated mice become diabetic after massive β-cell ablation.
(A) Experimental design. (B-C) Random-fed glycemia (B) and body weight (C) after DT in C57BL/6 males pre-treated with vehicle or mAb (N=3).
Figure 2—figure supplement 1
Anti-GCGR mAb administration recapitulates the metabolic and cellular phenotypes of Gcgr-/- mice.
(A) Experimental design. 9 mg/kg anti-GCGR mAb was injected i.p. 3 times per week for 3 weeks in C57BL/6 animals. (B) Left: Random fed glycemia of vehicle- (black squares) or mAb-treated males (red …
Figure 2—figure supplement 2
Insulin administration is required to stabilize body weight and allow survival of anti-GCGR-treated mice after DT.
(A-C) Exogenous insulin, but not anti-GCGR mAb treatment, stabilizes body weight and improves survival after extreme β-cell loss. (A) Experimental design. (B) Evolution of body weight following DT …
Figure 3 with 2 supplements
DT administration leads to a more complete β-cell ablation than STZ.
(A) Islet sections stained for insulin (red) and glucagon (green) from untreated, STZ-, or DT-treated RIP-DTR;Gcgr-/- females, 6 days after the last STZ or DT injection. Scale bars: 20 μm. (B-D) …
Figure 3—figure supplement 1
RIP-DTR;Gcgr-/- mice remain hyperglucagonemic and α-cell mass is not affected after STZ- or DT-treatment.
(A-B) fed plasma glucagon levels (A) and α-cell mass (B) in untreated (Untr.), STZ-, or DT-treated RIP-DTR;Gcgr+/- and RIP-DTR;Gcgr-/- males and females, measured 6 days after the last injection. …
Figure 3—figure supplement 2
Higher efficiency of β-cell ablation after DT- than after STZ-treatment in mice with normal glucagon signaling.
(A-B) β-cell mass (A) and pancreatic insulin content (B) in untreated (Untr.), STZ-, or DT-treated RIP-DTR;Gcgr+/- females, measured 6 days after the last injection. STZ administration: two …
Figure 4 with 3 supplements
Inhibition of insulin action triggers hyperglycemia in STZ-treated Gcgr-/-mice.
(A) Random-fed glycemia after STZ and/or S961 administration in Gcgr+/- and Gcgr-/- females (left), and area under the glycemia curve (AUC) during S961 treatment (right). (B-D) Hepatic Pepck (top) …
Figure 4—figure supplement 1
Higher hepatic PEPCK protein expression after DT in both Gcgr+/- and Gcgr-/- mice.
Western blot analysis showing PEPCK and Tubulin expression in the liver of untreated (untr.) and DT-treated RIP-DTR-Gcgr+/- and RIP-DTR-Gcgr-/- females (left). Quantification of PEPCK band …
Figure 4—figure supplement 2
Liver glycogen concentration is reduced after DT-treatment in both RIP-DTR-Gcgr+/- and RIP-DTR-Gcgr-/- mice.
Liver glycogen concentration in different conditions of insulin and/or glucagon deficiency (N=4). *p<0.05; Mann-Whitney U test.
Figure 4—figure supplement 3
Expression of genes negatively regulated by insulin signaling in skeletal muscle.
mRNA levels of genes inhibited by insulin in skeletal muscle (gastrocnemius), relative to those of untreated Gcgr+/- females (normalized to Actb, Gapdh, and Gusb) (N=4–6). Irs2, Insulin receptor …
Figure 5 with 1 supplement
Anti-GCGR mAb treatment does not normalize hyperglycemia after efficient STZ-mediated β-cell ablation.
(A) Random-fed glycemia in C57BL/6 males treated with STZ (single injection at day 0: 175 or 225 mg/kg) and/or anti-GCGR mAb (osmotic pump, days 6 to 14; N=3–6). (B) Area under the glycemia curves …
Figure 5—figure supplement 1
Hepatic Pepck and Glucokinase expression after STZ and/or anti-GCGR mAb treatment.
Liver Pepck (left) and Glucokinase (right) mRNA levels in mice treated with STZ (single injection at day 0: 175 or 225 mg/kg) and/or anti-GCGR mAb (osmotic pump, days 6 to 14) relative to those of …
Figure 6 with 1 supplement
Absence of glucagon signaling does not block the appearance of new glucagon-insulin bihormonal cells after β-cell ablation.
(A) Islet sections exhibiting glucagon-insulin co-expressing cells (arrowheads) from RIP-DTR;Gcgr+/+ and RIP-DTR;Gcgr-/- females (1 m after DT). Scale bars: 20 μm. (B-D) Percentage of glucagon+ …
Figure 6—figure supplement 1
Newly formed bihormonal cells in Gcgr-/- mice are reprogrammed α-cells.
(A) Transgenes required to irreversibly lineage-trace pancreatic α-cells with YFP before β-cell ablation. Inverted triangles represent loxP sites. (B) Experimental design. Upon DOX administration, …
Additional files
-
Supplementary file 1
Primer sequences used for RT-qPCR.
- https://doi.org/10.7554/eLife.13828.019
