Fig. 3.

MDCK-derived tubules model PKD and respond to treatment with different compounds. (A) Schematic representation of 3D collagen culture system. (B) A forskolin-stimulated microtubule showing many large spheroidal cysts stained with hematoxylin and eosin (insets). (C,D) Cysts are delimited by a monolayered epithelium positive for E-cadherin (white) in the basolateral membranes and (D) podocalyxin (green) in the apical membranes (insets). The tubular lumen is lost. (E–J) Forskolin-stimulated tubules after 7 days' treatment with (E) rapamycin, (F) Tolvaptan in combination with AVP, (G) OCTR, (H) PAS, (I) 2DG or (J) berberine. (I,J) 2DG and berberine treatments restore tubular lumen. (K,L) Quantification of cyst number/mm^2: No treatment (forskolin; 1205 ± 48.81); rapamycin (990 ± 174.5); OCTR (508.5 ± 39.52); PAS (688.9 ± 52.1); 2DG (348.1 ± 44.15); berberine (335.8 ± 27.93); AVP (1948 ± 283.4); AVP + Tolvaptan (716.4 ± 57). Data are expressed as means ± SEM from three independent experiments. (K) Number of fields analyzed: n = 18 for forskolin, n = 6 for rapamycin, n = 6 for OCTR, n = 7 for PAS, n = 8 for 2DG, n = 11 for berberine. *P < 0.05 versus PAS, °P < 0.0001 versus rapamycin, ^#P < 0.0001 versus forskolin by one-way ANOVA with Tukey's multiple comparisons test. (L) Number of fields analyzed: n = 4 for AVP, n = 9 for Tolvaptan in combination with AVP. **P < 0.0001 by two-tailed Student's t-test. DAPI, blue-stained nuclei; AVP, arginine vasopressin; OCTR, octreotide; PAS, pasireotide; 2DG, 2-deoxy-d-glucose. Scale bars: 100 μm (B), 50 μm (C, E–J), 20 μm (D).