Biofactors - Volume 31, issue 2

Authors: Schetinger, Maria Rosa C. | Morsch, Vera Maria | Bonan, Carla Denise | Wyse, Angela T.S.

Article Type: Research Article

Abstract: Extracellular nucleotides and nucleosides act as signaling molecules involved in a wide spectrum of biological effects. Their levels are controlled by a complex cell surface-located group of enzymes called ectonucleotidases. There are four major families of ectonucleotidases, nucleoside triphosphate diphosphohydrolases (NTPDases/CD39), ectonucleotide pyrophosphatase/phosphodiesterases (E-NPPs), alkaline phosphatases and ecto-5'-nucleotidase. In the last few years, substantial progress has been made toward the molecular identification of members of the ectonucleotidase families …and their enzyme structures and functions. In this review, there is an emphasis on the involvement of NTPDase and 5'-nucleotidase activities in disease processes in several tissues and cell types. Brief background information is given about the general characteristics of these enzymes, followed by a discussion of their roles in thromboregulatory events in diabetes, hypertension, hypercholesterolemia and cancer, as well as in pathological conditions where platelets are less responsive, such as in chronic renal failure. In addition, immunomodulation and cell-cell interactions involving these enzymes are considered, as well as ATP and ADP hydrolysis under different clinical conditions related with alterations in the immune system, such as acute lymphoblastic leukemia (ALL), B-chronic lymphocytic leukemia (B-CLL) and infections associated with human immunodeficiency virus (HIV). Finally, changes in ATP, ADP and AMP hydrolysis induced by inborn errors of metabolism, seizures and epilepsy are discussed in order to highlight the importance of these enzymes in the control of neuronal activity in pathological conditions. Despite advances made toward understanding the molecular structure of ectonucleotidases, much more investigation will be necessary to entirely grasp their role in physiological and pathological conditions. Show more

Keywords: NTPDases, ectonucleotidases, extracellular ATP, adenosine, purinergic system

Citation: BioFactors, vol. 31, no. 2, pp. 77-98, 2007

Authors: Chattopadhyay, Pronobesh | Shukla, Gunjan | Verma, Anurag | Wahi, A.K.

Article Type: Research Article

Abstract: The present study was aimed to evaluate the efficacy of L-arginine on mitochondrial function in ischemic and reperfusion (I/R) induced hepatic injury. Adult Wistar rat were subjected to 1 h of partial liver ischemia followed by 3 hour reperfusion. Eighteen wistar rats were divided into three groups viz. sham-operated control group (I) (n = 6), ischemia and reperfusion (I/R) group (II) (n = 6), L-arginine treated group (100 mg/kg body weight/daily by oral route for …7 days before induced ischemia reperfusion maneuver) (III) (n = 6). Mitochondrial injury was assessed in terms of decreased (P < 0.05) activities of mitochondrial antioxidant enzymes (GSH, SOD, CAT), respiratory marker enzymes (NADH dehydrogenase, cytochrome c oxidases) and hepatocytes nitric oxide production. Pre-treatment with L-arginine (10 mg/kg/p.o. for 7 days) significantly counteracted the alternations of hepatic enzymes and mitochondrial respiratory and antioxidant enzymes. In addition, electron microscopy and histopathology study showed the restoration of cellular normalcy and accredits the cytoprotective role of L-arginine against I/R induced hepatocellular injury. On the basis of these findings it may be concluded that L-arginine protects mitochondrial function in hepatic ischemic and reperfused liver. Show more

Keywords: Ischemic-reperfusion injury, mitochondrial respiratory enzymes, antioxidant enzymes, L-arginine

Citation: BioFactors, vol. 31, no. 2, pp. 99-106, 2007

Authors: Eguchi, Ai | Murakami, Akira | Li, Shiming | Ho, Chi-Tang | Ohigashi, Hajime

Article Type: Research Article

Abstract: Unregulated uptake of oxidized low-density lipoproteins (ox-LDL) via macrophage scavenger receptors (SRs) is a key event in atherosclerosis. We previously reported that nobiletin (NOB), a citrus polymethoxylated flavone, markedly reduced 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced SRs and adhesion molecules mRNA expression and blockade of DiI-acLDL uptake in THP-1 human monocyte-like cells. In this study, we examined the effects of NOB metabolites, 3'-hydroxy-5,6,7,8,4'-pentamethoxyflavone (3'-demethyl-NOB), 4'-hydroxy-5,6,7,8,3'-pentamethoxyflavone (4'-demethyl-NOB) and …3', 4'-dihydroxy-5,6,7,8,-tetramethoxyflavone (3', 4'-didemethyl-NOB) and NOB analog, tangeretin, on SRs and adhesion molecules mRNA expression. 3'-Demethyl-NOB significantly suppressed CD36 expression, moreover, 4'-demethyl- and 3', 4'-didemethyl-NOB significantly suppressed TPA-induced expression of SR-A and LOX-1. Further, the suppressive effects of 4'-demethyl- and 3', 4'-didemethyl-NOB on the expression of CD36 mRNA were greater extent than parent NOB. The inhibitory effects of the metabolites toward TPA-induced SR mRNA expression are partly associated with the suppression of AP-1 and NF-κB transcriptional activities. Together, our results suggest that metabolites of NOB, such as 4'-demethyl- and 3', 4'-didemethyl-NOB, have comparable or higher potentials to attenuate SR expression than NOB. Show more

Keywords: Oxidized LDL, scavenger receptors, nobiletin, metabolites, demethylnobiletin

Citation: BioFactors, vol. 31, no. 2, pp. 107-116, 2007

Authors: Eimani, H. | Mamzoji, S.S. | Soleimani, M.M. | Abnosi, M.H. | Valojerdi, M. Rezazadeh | Yazdi, P. Eftekhari | Shahverdi, A. | Guorabi, H.

Article Type: Research Article

Abstract: The aim of this study was to investigate the growth and survival rate of preantral follicles isolated from vitrified ovarian tissue by Cryotop and conventional methods. The ovaries of 14-day-old mice were separated and divided into four groups as following: Cryotop group, vitrified by Cryotop; CV (Conventional; CV) group, vitrified by conventional straw; toxicity test group and control group. After warming the vitrified ovaries, isolated preantral follicles from four groups were cultured for 4 days to …compare survival rate and follicular growth between above-mentioned groups. Survival rate (97.3%) in toxicity test group alike the control group (98.7%) were significantly higher (P < 0.05) than the Cryotop (92.7%) and CV (47.7%) groups. Increase in follicle diameters after 4 days in Cryotop and CV groups was significantly lower (P < 0.05) than the control and toxicity test groups, but growth and survival rate of follicles in Cryotop group was significantly higher (P < 0.05) than the CV group. These results demonstrated that ovarian tissue vitrification by Cryotop highly preserves the viability rate of preantral follicles. Show more

Keywords: Vitrification, ovarian tissue, preantral follicles, cryotop

Citation: BioFactors, vol. 31, no. 2, pp. 117-126, 2007

Authors: Safaralizadeh, Reza | Sirjani, Mahshid | Pourpak, Zahra | Kardar, Gholam Ali | Teimourian, Shahram | Shams, Sedigheh | Namdar, Zahra | Kazemnejad, Anoushiravan | Moin, Mostafa

Article Type: Research Article

Abstract: Introduction: Selenium is one of the essential trace elements which is more notified in children in recent years. Reliable age-specific reference values for selenium in children in Iran are not clear and are important for the identification of selenium deficiency and some other researches that is the aim of this study. Methods: Serum samples of 216 healthy children were analyzed by using hydride generation and flame atomic absorption spectroscopy to measured selenium level. …Results: The mean and standard deviation of serum selenium level in children 0–16 years old (mean: 39.83 months) was 72.14 ± 16.80 μg/l. There was significant difference in serum selenium concentration between two sexes which was 76.78 ± 15.24 μg/l and 69.56 ± 17.09 μg/l in girls and boys respectively (P value = 0.002). There was also a positive correlation between higher selenium serum concentration and age in both sexes. Conclusion: Essential trace element's normal ranges are fundamental data which could use in many studies. Serum selenium concentration in healthy Iranian children that found in this study is very close to serum concentration of European children. Our findings may reveal nutritional culture's similarity. Show more

Keywords: Selenium, hydride generation atomic absorption spectrometry

Citation: BioFactors, vol. 31, no. 2, pp. 127-131, 2007

Authors: Ambati, Suresh | Duan, Jiuhua | Duff, Emily | Choi, Yang-Ho | Hartzell, Diane L. | Della-Fera, Mary Anne | Baile, Clifton A.

Article Type: Research Article

Abstract: Ciliary neurotrophic factor (CNTF) and leptin are cytokine-like% hormones and act on their corresponding receptors in the hypothalamic arcuate nucleus (ARC). The present study was designed to assess effects of intracerebroventricular (ICV) injection of leptin and CNTF on gene expression in micropunched hypothalamic arcuate nucleus-median eminence (ARC-ME) complex samples from rats. Male Sprague Dawley rats were implanted with lateral cerebroventricular cannulas for administration of control, 10 μg/d leptin or 5 μg/d CNTF …for four days. Real-time Taqman™ RT-PCR was used to quantitatively compare the mRNA levels of selected genes in the ARC-ME complex. Leptin and CNTF increased ARC-ME mRNA levels of signal transducer and activator of transcription 3 (STAT3) by 64.5 and 124.7% (p < 0.01), suppressor of cytokine signaling 3 (SOCS3) by 258.9 and 1063.9% (p < 0.01), cocaine and amphetamine regulated transcript (CART) by 102.7 and 123.1% (p < 0.01), and proopiomelanocortin (POMC2) by 374.1 and 264.9% (p < 0.01), respectively. Leptin increased growth hormone releasing hormone (GHRH) by 309.9% (p < 0.01), while CNTF increased janus kinase 2 (JAK2) mRNA by 31.7% (p < 0.01) and decreased gonadotropin releasing hormone 1 (GNRH1) by 59.7% (p < 0.01), mitogen activated protein kinase 1 (MAPK1) by 19.4% (p < 0.05) and tyrosine hydroxylase (TH) by 74.5% (p < 0.05). Significant reduction in daily food intake and body weights by both the treatments was observed. Also, decrease in weights of fat pads was concomitant with lowered serum insulin and leptin levels. Our findings show that leptin and CNTF engage both convergent and divergent pathways involved in feeding, cellular signaling, inflammation, and other related regulatory systems. Show more

Keywords: mRNA expression, feeding, RT-PCR, peptide, ICV, regulation

Citation: BioFactors, vol. 31, no. 2, pp. 133-144, 2007