Expression of aldo-keto reductase family 1 member C1 (AKR1C1) gene in porcine ovary and uterine endometrium during the estrous cycle and pregnancy

<p>Abstract</p> <p>Background</p> <p>The aldo-keto reductase family 1 member C1 (AKR1C1) belongs to a superfamily of NADPH-dependent reductases that convert a wide range of substrates, including carbohydrates, steroid hormones, and endogenous prostaglandins. The 20alpha-hydroxysteroid dehydrogenase (20alpha-HSD) is a member of AKR family. The aims of this study were to determine its expression in the ovary and uterus endometrium during the estrous cycle and pregnancy.</p> <p>Methods</p> <p>Rapid amplification of cDNA ends (RACE) experiments were performed to obtain the 5' and 3' ends of the porcine <it>20alpha-HSD </it>cDNA. Reverse-transcriptase-PCR (RT-PCR), real-time PCR, northern blot analysis, and western blot analysis were performed to examine the expression of porcine 20alpha-HSD. Immunohistochemical analysis was also performed to determine the localization in the ovary.</p> <p>Results</p> <p>The porcine 20alpha-HSD cDNA is 957 bp in length and encodes a protein of 319 amino acids. The cloned cDNA was virtually the same as the porcine <it>AKR1C1 </it>gene (337 amino acids) reported recently, and only differed in the C-terminal region (the <it>AKR1C1 </it>gene has a longer C-terminal region than our sequence). The <it>20alpha-HSD </it>gene (from now on referred to as <it>AKR1C1</it>) cloned in this paper encodes a deletion of 4 amino acids, compared with the C-terminal region of <it>AKR1C1 </it>genes from other animals. Porcine AKR1C1 mRNA was expressed on day 5, 10, 12, 15 of the cycle and 0-60 of pregnancy in the ovary. The mRNA was also specifically detected in the uterine endometrium on day 30 of pregnancy. Western blot analysis indicated that the pattern of AKR1C1 protein in the ovary during the estrous cycle and uterus during early pregnancy was similar to that of <it>AKR1C1 </it>mRNA expression. The recombinant protein produced in CHO cells was detected at approximately 37 kDa. Immunohistochemical analysis also revealed that pig AKR1C1 protein was localized in the large luteal cells in the early stages of the estrous cycle and before parturition.</p> <p>Conclusions</p> <p>Our study demonstrated that AKR1C1 mRNA and protein are coordinately expressed in the luteal cell of ovary throughout the estrous cycle and in the uterus on day 30 of pregnancy. Thus, the porcine AKR1C1 gene might control important mechanisms during the estrous cycle.</p

Electroanalytical Applications Based on Carbon Nanotube/Prussian Blue Screen-printable Composite

A single step fabrication process of carbon nanotube/Prussian Blue (CNT/PB) paste electrodes based on screen printing technology has been studied as an amperometric sensor for the determination of hydrogen peroxide and free chlorine. Compared to the classical carbon paste (CP) electrode, the CNT paste electrode greatly enhanced the response in the presence of hydrogen peroxide due to the electrocatalytic activity of the CNT. Based on the CNT/binder paste, PB was also incorporated into a network of CNT paste and characterized. The best electroanalytical properties of PB-mixed sensors to hydrogen peroxide were obtained with PB ratio of 10 wt % composition, which showed fast response time (t90 ≤ 5 s; 0.2- 0.3 mM), low detection limit of 1.0 µM, good linear response in the range from 5.0 × 10‒5- 1.0 × 10‒3 mol L‒1 (r2 = 0.9998), and high sensitivity of ‒8.21 µA mM‒1. In order to confirm the enhanced electrochemical properties of CNT/PB electrode, the sensor was further applied for the determination of chlorine in water, which exhibited a linear response behavior in the range of 50- 2000 ppb for chlorine with a slope of 1.10 µA ppm‒1 (r2 = 9971)