Tadalafil increases axonal remodeling in diabetic db/db mice.

<p>Panels A to C show semi-thin toluidine blue-stained cross sections of sciatic nerves from a representative non-diabetic mouse (DM, A), diabetic mouse treated with saline (DB, B), and diabetic mouse treated with tadalafil (DBTA, C). The table shows the effect of tadalafil on histomorphometric parameter of sciatic nerves. Values are mean±SE. *p<0.05 and #p<0.05 versus the non-diabetic mouse (DM) and the diabetic mouse treated with saline (DB), respectively. n = 10/group. Bar = 20μm. DBTA = diabetic mouse treated with tadalafil.</p

Tadalafil increases intraepidermal nerve fiber density in diabetic db/db mice.

<p>Panels A to C show PGP 9.5 immunoreactive intraepidermal nerve fibers (red, arrows) in the plantar skin from a representative non-diabetic mouse treated with saline (DM, A), diabetic mouse treated with saline (DB, B) and diabetic mouse treated with tadalafil (DBTA, C). Panel D shows quantitative data. *p<0.05 and #p<0.05 versus the non-diabetic mouse (DM) and the diabetic mouse treated with saline (DB), respectively. n = 10/group. Bar = 50μm. DBTA = diabetic mouse treated with tadalafil.</p

Effect of tadalafil on blood glucose.

<p>Effect of tadalafil on blood glucose.</p

Letters adjacent to boxed areas in schematic representation of a brain coronal section (A) indicate areas where representative confocal microscopic images were taken.

<p>Panels B and C show YFP (green) and DCX (red) positive cells in non-ischemic (B) and ischemic SVZ (C) in middle-aged mice 30 days after stroke. Orthogonal views (D, E) show that a YFP immunoreactive cell (green) was DCX positive (D, red) or NeuN (NN) positive (E) in the ischemic striatum. Quantitative data analysis (F) shows percentage of YFP/DCX and YFP/NeuN positive cells in the ischemic striatum after treatment with saline and Sildenafil. *p<0.05 vs the saline group. n = 10/saline and n = 11/Sildenafil. Bar = 10 µm for B to E. Blue color  =  cell nuclei. CC  =  corpus callosum, and LV  =  lateral ventricle.</p

Representative confocal microscopic images (A to F, H, I) show that YFP immunoreactive cells (green) were NG (A, B, red), CNPase (C, D, red), CC1 (E, F, red), and GFAP (H, I, red) positive in the corpus callosum (A, C, E), striatum (B, D, F, H) and SVZ (I) of the ischemic hemisphere in middle-aged mice 30 days after stroke.

<p>Panel G shows percentage of YFP/CNPase positive cells in the ipsilateral corpus callosum and striatum in middle-aged mice treated with saline and Sildenafil. *p<0.05 vs saline group. n = 10/saline and n = 11/Sildenafil. Bars  = 10 µm. Blue color  =  cell nuclei. CC  =  corpus callosum, LV  =  lateral ventricle.</p

The number of YFP⁺ cells in the ischemic hemisphere.

<p>Date are presented as Mean ± SE. CC  =  corpus callosum. SVZ  =  subventricular zone.</p>*<p> =  P<0.05 vs the saline group.</p

Tadalafil improves vascular function in the sciatic nerve tissue.

<p>Panels A to I show FITC-dextran perfused vessels from whole mounted (A to C) and cross sections (D to F) of the sciatic nerve tissue, and CD31 immunoreactive blood vessels at the cross section (G and I) of the sciatic nerve tissue from a representative non-diabetic mouse treated with saline (DM, A, D and G), diabetic mouse treated with saline (DB, B, E and H), and diabetic mouse treated with tadalafil (DBTA, 10 mg/kg, C, F and I). Panels J to L show quantitative data of density of FITC-dextran perfused vessels in cross section (J, n = 6/group), CD31 immunoreactive vascular perimeters (K, n = 6/group), and percentage changes of sciatic nerve blood flow with a reference of non-diabetic mouse at 100% (L, n = 5/group). *p<0.05 and #p<0.05 versus the non-diabetic mouse (DM) and the diabetic mouse treated with saline (DB), respectively. Bar = 100μm. DBTA = diabetic mouse treated with tadalafil.</p

A diagram shows experimental protocols (A).

<p>Confocal microscopic images show YFP positive cells in non-ischemic brain 14 days after injection of tamoxifen (B and C) and YFP positive cells in ischemic striatum 30 days after middle cerebral artery occlusion (MCAO, D). An orthogonal view shows that several YFP immunoreactive cells (green) were nestin positive (red) in the anterior SVZ of the lateral ventricle of non-ischemic brain (C). A light microscopic image of hematoxylin and eosin (H&E) stained coronal section shows striatal ischemic lesion 30 days after MCAO (E). Bars = 100 µm for B, and D, 10 µm in C, and 100 µm in E. Blue color  =  cell nuclei. LV  =  lateral ventricle. D0 represents the day of MCAO.</p

NGF and PDGF-C protein levels.

<p>Representative images of double immunofluorescent staining show that NGF and PDGF-C immunoreactivity (B, C, E, F, red, arrows) was co-localized to S100 positive Schwann cells (A, D, green, arrows). Western blot analysis (G) shows NGF and PDGF-C levels in the sciatic nerve tissue and β-actin was used as an internal control. *p<0.05 and #p<0.05 versus the non-diabetic mouse (DM) and the diabetic mouse treated with saline (DB), respectively. n = 6/group. Bar = 50μm. DBTA = diabetic mouse treated with tadalafil.</p

GFAP⁺ processes at ventricular surface.

<p>Double and triple immunofluorescent images acquired from the apical surface of representative non-ischemic (A, B) and ischemic (C, D) whole mounts show acetylated tubulin⁺ cilium and γ-tubulin⁺ basal bodies (A, C) and cells with single γ-tubulin⁺ basal body, GFAP⁺ processes at the center of β-catenin⁺ cobblestone ependymal cells (B, D). Quantitative data (E, F) show the number of cells with GFAP⁺ processes on the apical surface. *p<0.05, n = 6 mice/group. Bar = 10 µm.</p