Assessment of an iPad-based sperm motility analyzer for determination of canine sperm motility

The objective of this study was to evaluate the repeatability and accuracy of canine sperm motility (total and progressive) assessment with a tablet-based Canine iSperm instrument compared to computer-assisted sperm analysis (CASA). The experiment used fresh and frozen/thawed canine semen samples for comparisons of semen analysis parameters (concentration, total motility, and progressive motility) between a CASA system, iSperm, and NucleoCounter SP-100 (concentration) instruments. Spearman's Rho correlational analysis was used to identify significant associations between motility assessment methods. Significant positive correlations were found between CASA assessment and iSperm for both progressive and total motility measurements. We also determined the coefficient of variation (CV) for repeatability of sample analysis for iSperm and CASA for fresh sperm, wherein each sample was assessed 10 times on both devices. For fresh and frozen-thawed samples, concentration assessment by iSperm showed high variability (CV= 19.9 ± 1.5%). For iSperm assessment of total and progressive motility, the CVs were 6.3 ± 0.5% and 10.7 ± 0.8%, respectively. The results indicate that the iSperm application offers an accurate and alternative measurement of motility to traditional CASA analysis, though caution should be taken when assessing concentration due to the high CV observed in this study.

Wnt-induced secreted protein-1 is a prohypertrophic and profibrotic growth factor

Wnt1-induced secreted protein-1 (WISP-1) is a member of the cysteine-rich 61, connective tissue growth factor, and nephroblastoma overexpressed (CCN) family of growth factors and is expressed in the heart at low basal levels. The purpose of this study was to investigate whether WISP-1 is upregulated in postinfarct myocardium and whether WISP-1 exerts prohypertrophic and mitogenic effects stimulating myocyte hypertrophy, cardiac fibroblast (CF) proliferation, and collagen expression. Male C57Bl/6 (25 g) mice underwent permanent occlusion of the left anterior descending coronary artery. mRNA and protein levels were analyzed by Northern and Western blot analyses. Cardiomyocyte hypertrophy was quantified by protein and DNA synthesis. CF proliferation was quantified by CyQuant assay, and soluble collagen release by Sircol assay. A time-dependent increase in WISP-1 expression was detected in vivo in the noninfarct zone of the left ventricle, which peaked at 24 h (3.1-fold, P < 0.01). Similarly, biglycan expression was increased by 3.71-fold (P < 0.01). IL-1beta and TNF-alpha expression preceded WISP-1 expression in vivo and stimulated WISP-1 expression in neonatal rat ventricular myocytes in vitro. WISP-1-induced cardiomyocyte hypertrophy was evidenced by increased protein (2.78-fold), but not DNA synthesis, and enhanced Akt phosphorylation and activity. Treatment of primary CF with WISP-1 significantly stimulated proliferation at 48 h (6,966 +/- 264 vs. 5,476 +/- 307 cells/well, P < 0.01) and enhanced collagen release by 72 h (18.4 +/- 3.1 vs. 8.4 +/- 1.0 ng/cell, P < 0.01). Our results demonstrate for the first time that WISP-1 and biglycan are upregulated in the noninfarcted myocardium in vivo, suggesting a positive amplification of WISP-1 signaling. WISP-1 stimulates cardiomyocyte hypertrophy, fibroblast proliferation, and ECM expression in vitro. These results suggest that WISP-1 may play a critical role in post-myocardial infarction remodeling.

Phosphorylation of bovine rod photoreceptor cyclic GMP phosphodiesterase

The cyclic GMP phosphodiesterase (PDE) of retinal rods plays a key role in phototransduction and consists of two catalytic subunits (PDE alpha and PDE beta) and two identical inhibitory subunits (PDE gamma). Here we report that PDE alpha and PDE gamma are phosphorylated by protein kinase(s) C (PKC) from brain and rod outer segments (ROS). These same two types of PKC also phosphorylate PDE alpha in trypsin-activated PDE (without PDE gamma). In contrast, cyclic-AMP-dependent protein kinase catalytic subunit phosphorylates both PDE alpha and PDE beta, but not PDE gamma. This kinase does not phosphorylate trypsin-activated PDE. The synthetic peptides AKVISNLLGPREAAV (PDE alpha 30-44) and KQRQTRQFKSKPPKK (PDE gamma 31-45) inhibited phosphorylation of PDE by PKC from ROS. These data suggest that sites (at least one for each subunit) for phosphorylation of PDE by PKC are localized in these corresponding regions of PDE alpha and PDE gamma. Isoenzyme-specific PKC antibodies against peptides unique to the alpha, beta, gamma, delta, epsilon and zeta isoforms of protein kinase C were used to show that a major form of PKC in ROS is PKC alpha. However, other minor forms were also present.