Sonic hedgehog protein is decreased and penile morphology is altered in prostatectomy and diabetic patients.

Erectile dysfunction (ED) is a debilitating medical condition and current treatments are ineffective in patients with cavernous nerve (CN) injury, due to penile remodeling and apoptosis. A critical regulator of penile smooth muscle and apoptosis is the secreted protein sonic hedgehog (SHH). SHH protein is decreased in rat prostatectomy and diabetic ED models, SHH inhibition in the penis induces apoptosis and ED, and SHH treatment at the time of CN injury suppresses smooth muscle apoptosis and promotes regeneration of erectile function. Thus SHH treatment has significant translational potential as an ED therapy if similar mechanisms underlie ED development in patients. In this study we quantify SHH protein and morphological changes in corpora cavernosal tissue of control, prostatectomy and diabetic patients and hypothesize that decreased SHH protein is an underlying cause of ED development in prostatectomy and diabetic patients. Our results show significantly decreased SHH protein in prostatectomy and diabetic penis. Morphological remodelling of the penis, including significantly increased apoptotic index and decreased smooth muscle/collagen ratio, accompanies declining SHH. SHH signaling is active in human penis and is altered in a parallel manner to previous observations in the rat. These results suggest that SHH has significant potential to be developed as an ED therapy in prostatectomy and diabetic patients. The increased apoptotic index long after initial injury is suggestive of ongoing remodeling that may be clinically manipulatable

Elevated Atmospheric CO 2 Alters Soil Microbial Communities Associated with Trembling Aspen ( Populus tremuloides ) Roots

Global atmospheric CO 2 levels are expected to double within the next 50 years. To assess the effects of increased atmospheric CO 2 on soil ecosystems, cloned trembling aspen ( Populus tremuloides ) seedlings were grown individually in 1 m 3 open bottom root boxes under either elevated (720 ppm, ELEV) or ambient CO 2 (360 ppm, AMB). After 5 years, soil cores (40 cm depth) were collected from the root boxes and divided into 0–20 cm and 20–40 cm fractions. ELEV treatment resulted in significant decreases in both soil nitrate and total soil nitrogen in both the 0–20 cm and 20–40 cm soil fractions, with a 47% decrease in soil nitrate and a 50% decrease in total soil nitrogen occurring in the 0–20 cm fraction. ELEV treatment did not result in a significant change in the amount of soil microbial biomass. However, analysis of indicator phospholipid fatty acids (PLFA) indicated that ELEV treatment did result in significant increases in PLFA indicators for fungi and Gram-negative bacteria in the 0–20 cm fraction. Terminal restriction fragment length polymorphism (T-RFLP) analysis was used to analyze the composition of the soil bacterial communities (using primers targeting the 16SrRNA gene) and the soil fungal communities (using primers targeting the intergenic transcribed spacer region). T-RFLP analysis revealed shifts in both bacterial and fungal community structure, as well as increases in both bacterial and fungal species richness with ELEV treatment. These results indicated that increased atmospheric CO 2 had significant effects on both soil nutrient availability and the community composition of soil microbes associated with aspen roots.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48116/1/248_2004_Article_120.pd

Trichrome and TUNEL were performed on corpora cavernosal tissue from control, prostatectomy, and diabetic patients.

<p>The smooth muscle/collagen ratio decreased 25% in prostatectomy and 28% in diabetic penis (p = 0.0338). The apoptotic index increased 22% in prostatectomy and 25% in diabetic penis (p = 0.0141). Arrows indicate staining. 100–400× magnification.</p

Quantification of precursor and active SHH protein by western analysis of corpora cavernosal tissue from control, prostatectomy and diabetic patients.

<p>Precursor SHH protein significantly decreased 41% in prostatectomy and 39% in diabetic patients (p = 0.0312). Active SHH protein significantly decreased 46% in prostatectomy and 48% in diabetic patients in comparison to controls (p = 0.0222). Asterisks indicate significance. Where error bars do not appear they are too small to be shown on the graph.</p

ED severity as measured by IIEF in control, prostatectomy and diabetic patients.

<p>ED severity as measured by IIEF in control, prostatectomy and diabetic patients.</p

(A) Dual TUNEL/α-ACTIN IHC was performed using colorimetric and fluorescent techniques.

<p>Apoptosis was barely detectable in control penile smooth muscle. Apoptosis was abundant in prostatectomy and diabetic corpora cavernosal tissue and almost all apoptosis observed co-localized with α-ACTIN in penile smooth muscle. TUNEL appears in brown (diaminobenzidine, DAB, top) and red (bottom). α-ACTIN appears in red (top) and bluish-purple (bottom). Light blue staining is unavoidable auto-fluorescence present in human penis. Arrows indicate co-localization (shown in pink on bottom). 400× magnification. (B) TUNEL/CD31 IHC shows that apoptosis is also occurring at a very low level in the endothelium. TUNEL appears in brown (DAB) and CD31 appears in red. Arrows indicate co-localization. 400× magnification. Fluorescent co-localization for TUNEL/CD31 was not possible due to the low abundance of endothelium and the high auto-fluorescence present in human penile tissue.</p

Quantification of precursor and active SHH protein by western analysis of rats that underwent bilateral CN crush and sildenafil or DMSO treatment for 7 or 14 days.

<p>Precursor and active SHH proteins were significantly increased 50% and 57% (p = 0.02 and 0.04) after 14 days of sildenafil treatment.</p

<i>In situ</i> for <i>Shh</i> RNA and IHC for SHH protein, were performed on corpora cavernosal tissue from control, prostatectomy, and diabetic patients.

<p><i>Shh</i> RNA and SHH protein are present in smooth muscle and the localization was unchanged in prostatectomy and diabetic penis. SHH protein appears decreased by visual observation in prostatectomy and diabetic penis. PTCH1 (SHH receptor) and BDNF (SHH target in the rat) were also decreased in prostatectomy and diabetic penis. Arrows indicate staining. 100–400× magnification.</p

Quantification of α-ACTIN by western analysis of corpora cavernosal tissue from control, prostatectomy and diabetic patients.

<p>α-ACTIN was significantly decreased 52% in prostatectomy and 51% in diabetic (p = 0.005) corpora cavernosa.</p