bluuebunny/crossref_metadata_2025 huggingface dataset:
Dietary Whey Protein Modulates Liver Glycogen Level and Glycoregulatory Enzyme Activities in Exercise-Trained Rats
Authors: Morifuji Masashi , Sakai Kensuke , Sugiura Katsumi
Published: July 2017

This study compared the effects of dietary whey protein with dietary casein or soy protein on glycogen storage and glycoregulatory enzyme activities in the liver of sedentary and exercise-trained rats. Male Sprague-Dawley rats (ca. 130 g) were divided into one sedentary and three exercise-trained groups, with eight animals in each group. Casein was provided as the source of dietary protein in the sedentary group while the exercise-trained groups were fed casein, whey, or soy protein. Rats in the exercise-trained groups ran for 30 mins/day, 4 days/week on a motor-driven treadmill. In the exercise-trained rats, animals fed whey protein had higher liver glycogen content than animals in the other two diet groups. Glucokinase activity was significantly higher in rats fed whey protein compared to that in rats fed soy protein, while glucose 6-phosphatase activity was significantly decreased in animals on the whey protein diet compared with those the other two diets. Although 6-phosphofructokinase activity was significantly lower in the whey protein group than in the soy protein group, we found that fructose 1,6-bisphosphatase activity was significantly higher in the whey group compared with either the casein or soy groups. Pyruvate kinase activity in rats fed the casein diet was significantly higher than in rats fed either the whey or soy protein diets. In addition, hepatic alanine aminotransferase activity and serum alanine level were also increased in the whey protein group compared with the casein or soy protein groups. Taken together, these results demonstrate that the whey protein diet in exercise-trained rats results in significantly higher levels of liver glycogen, because of the combined effects of regulation of rate limiting glycolytic and gluconeogenic enzyme activities and activation of glycogenesis from alanine via alanine aminotransferase.
Glutathione Preconditioning Attenuates Ac-LDL–lnduced Macrophage Apoptosis via Protein Kinase C–Dependent Ac-LDL Trafficking
Authors: Rosenson-Schloss Rene S. , Chnari Evangelia , Brieva Thomas A. , Dang Anh , Moghe Prabhas V.
Published: July 2017

Oxidized low-density lipoprotein (ox-LDL) incorporation into intlmally resident vascular cells via scavenger receptors marks one of the early steps in atherosclerosis. Cellular apoptotic damage results from two major serial intracellular events: the binding and scavenger receptor-mediated uptake of oxldizable lipoproteins and the intracellular oxidative responses of accumulated lipoproteins. Most molecular approaches to prevent apoptotic damage have focused on singular events within the cascade of lipoprotein trafficking. To identify a multifocal strategy against LDL-induced apoptosis, we evaluated the role of cellular preconditioning by glutathione-ethyl ester (GSH-Et), a native redox regulator, in the prevention of the uptake and apoptotic effects of an oxldizable scavenger receptor-specific ligand, acetylated low-density lipoprotein (Ac-LDL). Our results indicate that GSH-Et–mediated protein kinase C (PKC) pathway modulation regulates Ac-LDL binding and incorporation into GSH-Et preconditioned cells and subsequently delays reactive oxygen intermediate generation and apoptotic conversion. The GSH-Et protective effects on apoptosis and Ac-LDL binding were reversed by calphostin C, a PKC inhibitor, and were accompanied by an increase in PKC phosphorylation. However, the rate of reactive oxygen intermediate accumulation was not increased following calphostin C treatment, suggesting that GSH-Et may play an important nonreactive oxygen-intermediate–based protective role in regulating apoptotic dynamics. Overall, we report on the novel role for GSH-Et preconditioning as a molecular strategy to limit lipoprotein entry Into the cells, which presents a proactive modality to prevent cellular apoptosis in contrast with the prevalent antioxidant approaches that treat damage retroactively.
Proinflammatory Cytokines and the Hypermetabolism of Children with Sickle Cell Disease
Authors: Hibbert Jacqueline M. , Hsu Lewis L. , Bhathena Sam J. , Irune Ikovwa , Sarfo Bismark , Creary Melissa S. , Gee Beatrice E. , Mohamed Ali I. , Buchanan Iris D. , Al-Mahmoud Ahmad , Stiles Jonathan K.
Published: July 2017

Sickle cell anemia (HbSS) includes chronic inflammation, but the origin is unclear. We hypothesized that in stable HbSS patients the inflammation was associated with hypermetabolism. We compared selected hypermetabolic and key Immuno-modulator indicators in HbSS versus control children and examined associations between measures of hypermetabolism and inflammation. Twelve fasting asymptomatic HbSS children 6–12 years and 9 controls matched for age, gender and fat mass (FM) were studied. Proportional reticulocyte count (retic%) and resting energy expenditure (REE) represented hypermetabolism, and C-reactive protein (CRP) Indicated Inflammation. Proinflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), chemokine monocyte chemoattractant proteln-1 (MCP-1), and energy balance cytokine leptin were measured. Methods were indirect calorimetry, enzyme-linked immunosorbent assay, and radioimmunoassay. Statistical analysis included simple correlation and regression analysis. REE (51 ± 6 vs. 43 ± 12 kcal/kg per fat-free mass (FFM), mean ± SD), retic% (12 ± 4 vs. 0.7 ± 0.3%), CRP (5 ± 3 vs. 0.3 ± 0.4 mg/liter), and IL-6 (71 ± 40 vs. 20 ± 7 pg/ml) were significantly higher for HbSS than controls (P < 0.05). Conversely, leptin (0.1 ± 0.1 vs. 2 ± 1 µg/liter per kgFM) and MCP-1 (34 ± 5 vs. 41 ± 4 pg/ml) were significantly lower for the HbSS subjects (P < 0.01). TNF-α was not significantly different. There were no significant associations between REE or retic% and any cytokine measured. However, CRP was significantly associated with REE in HbSS (r = 0.8, P = 0.003) and an important predictor of REE/FFM. We provide new evidence for low circulating levels of inflammatory chemokine MCP-1 in stable HbSS children, confirm mostly low cytokine levels, inflammation, and hypermetabolism and demonstrate association of hypermetabolism with inflammation via CRP but not via cytokines.
When Melatonin Gets on Your Nerves: Its Beneficial Actions in Experimental Models of Stroke
Authors: Reiter Russel J. , Tan Dun-xian , Leon Josefa , Kilic Ülkan , Kilic Ertugrul
Published: July 2017

This article summarizes the evidence that endogenously produced and exogenously administered melatonin reduces the degree of tissue damage and limits the biobehavioral deficits associated with experimental models of ischemia/reperfusion injury in the brain (i.e., stroke). Melatonin's efficacy in curtailing neural damage under conditions of transitory interruption of the blood supply to the brain has been documented in models of both focal and global ischemia. In these studies many indices have been shown to be improved as a consequence of melatonin treatment. For example, when given at the time of ischemia or reperfusion onset, melatonin reduces neurophysio-logical deficits, infarct volume, the degree of neural edema, lipid peroxidation, protein carbonyls, DNA damage, neuron and glial loss, and death of the animals. Melatonin's protective actions against these adverse changes are believed to stem from its direct free radical scavenging and indirect antioxidant activities, possibly from its ability to limit free radical generation at the mitochondrial level and because of yet-undefined functions. Considering its high efficacy in overcoming much of the damage associated with ischemia/reperfusion injury, not only in the brain but in other organs as well, its use in clinical trials for the purpose of improving stroke outcome should be seriously considered.
Blood Concentrations of Th2-Type Immunoglobulins are Selectively Increased in Weanling Mice Subjected to Acute Malnutrition
Authors: Neyestani Tirang R. , Woodward Bill
Published: July 2017

Male and female C57BL/6J mice, initially 19 days old, consumed a complete purified diet either ad libitum (age-matched control) or in restricted daily quantities (energy deficiency), or they consumed a purified isocaloric low-protein diet ad libitum (protein and energy deficit). In a 14-day experimental period, malnourished animals lost approximately 1.5% of their initial body weight daily. Zero-time controls, 19 days old, were also included in the study. Serum levels of Th2-type (IgG1 and IgE) and Th1-type (IgG2a and IgG3) immunoglobulins were quantified by enzyme-linked immunosorbent assay, and total IgG concentration was also assessed. Both malnourished groups exhibited high serum concentrations of IgG1 and IgE relative to the age-matched control group, whereas levels of the Th1-type immunoglobulins were unaffected. Total IgG concentration in the malnourished groups reflected the usual finding in humans (i.e., no effect or elevated). The results are consistent with the proposition of Th2-polarized immune competence in acute weanling deficiencies of energy, protein, or both.
Soyasaponins Lowered Plasma Cholesterol and Increased Fecal Bile Acids in Female Golden Syrian Hamsters
Authors: Lee Sun-Ok , Simons Andrean L. , Murphy Patricia A. , Hendrich Suzanne
Published: July 2017

A study was conducted in hamsters to determine if group B soyasaponins improve plasma cholesterol status by increasing the excretion of fecal bile acids and neutral sterols, to identify group B soyasaponin metabolites, and to investigate the relationship between a fecal group B soyasaponin metabolite and plasma lipids. Twenty female golden Syrian hamsters, 11–12 weeks old and 85–125 g, were randomly assigned to a control diet or a similar diet containing group B soyasaponins (containing no isoflavones), 2.2 mmol/kg, for 4 weeks. Hamsters fed group B soyasaponins had significantly lower plasma total cholesterol (by 20%), non–high-density lipoprotein (HDL) cholesterol (by 33%), and triglycerides (by 18%) compared with those fed casein (P < 0.05). The ratio of total cholesterol to HDL cholesterol was significantly lower (by 13%) in hamsters fed group B soyasaponins than in those fed casein (P < 0.05). The excretion of fecal bile acids and neutral sterols was significantly greater (by 105% and 85%, respectively) in soyasaponin-fed hamsters compared with those fed casein (P < 0.05). Compared with casein, group B soyasaponins lowered plasma total cholesterol levels and non-HDL cholesterol levels by a mechanism involving greater excretion of fecal bile acids and neutral sterols. Hamsters fed group B soyasaponins statistically clustered into two fecal soyasaponin metabolite–excretion phenotypes: high excreters (n = 3) and low excreters (n = 7). When high and low producers of this soyasaponin metabolite were compared for plasma cholesterol status, the high producers showed a significantly lower total-cholesterol-to-HDL-cholesterol ratio compared with the low producers (1.38 ± 0.7 vs. 1.59 ± 0.13; P < 0.03). Greater production of group B soyasaponin metabolite in hamsters was associated with better plasma cholesterol status, suggesting that gut microbial variation in soyasaponin metabolism may influence the health effects of group B soyasaponins.
The HIV-1 Tat Protein Selectively Enhances CXCR4 and Inhibits CCR5 Expression in Megakaryocytic K562 Cells
Authors: Mondal Debasis , Williams Christopher A. , Ali Mussa , Eilers Mark , Agrawal Krishna C.
Published: July 2017

The hematopoietic compartments act as long-term reservoirs for human immunodeficiency virus type-1 (HIV-1). Although hematopoietic progenitor cells (HPCs) are rarely infectable, HPCs committed to the megakaryocytic lineage can be infected and support a productive infection by both the X4 and R5 strains of HIV-1. Indeed, in contrast to the CD34+ progenitors, the lineage-committed HPCs express high levels of the HIV-1 co-receptors, CXCR4 and CCR5. The HIV-1 transactivator (Tat) protein has been shown to alter co-receptor expression in T lymphocytes and macrophages. We hypothesized that Tat may regulate co-receptor expression in lineage-specific HPCs as Well. We have monitored the effects of Tat protein on co-receptor expression and on lineage-specific differentiation, using the HPC cell line, K562. Butyric acid (BA)-induced erythroid differentiation in K562 cells was suppressed by 1–100 ng/ml of Tat, as evident from a 70–80% decrease in hemoglobin (Hb) production and a 10–30-fold decrease in glycophorin-A expression. However, Tat treatment enhanced phorbol myristate acetate (PMA)-induced megakaryocytic differentiation, as evident from a 180–210% increase in3H-serotonin uptake and a 5–12-fold increase in CD61 expression. Tat did not significantly alter co-receptor expression in erythroid cells. However, Tat co-treatment profoundly effected both CXCR4 and CCR5 gene expression and protein levels in megakaryocytic cells. In PMA-stimulated cells, Tat increased CXCR4 and decreased in CCR5 expression, this was potentiated in cells chronically exposed to Tat. In conclusion, Tat protein suppresses erythroid and facilitates megakaryocytic differentiation of K562 cells. In megakaryocytic cells, Tat differentially effected CXCR4 and CCR5 expression. Because megakaryocytes may play a crucial role in HIV-1 infectivity in viral reservoirs, our findings implicate a role for Tat protein in dictating co-receptor usage in lineage-committed HPCs.
The Tetratricopeptide Repeat Domain 7 Gene is Mutated in Flaky Skin Mice: A Model for Psoriasis, Autoimmunity, and Anemia
Authors: Helms Cynthia , Pelsue Stephen , Cao Li , Lamb Erika , Loffredo Brett , Taillon-Miller Patricia , Herrin Brooke , Burzenski Lisa M. , Gott Bruce , Lyons Bonnie L. , Keppler Deana , Shultz Leonard D. , Bowcock Anne M.
Published: July 2017

The flaky skin (fsn) mutation in mice causes pleiotropic abnormalities including psoriasiform dermatitis, anemia, hyper-IgE, and anti-dsDNA autoantibodies resembling those detected in systemic lupus erythematosus. The fsn mutation was mapped to an interval of 3.9 kb on chromosome 17 between D17Mit130 and D17Mit162. Resequencing of known and predicted exons and regulatory sequences from this region in fsn/fsn and wild-type mice indicated that the mutation is due to the insertion of an endogenous retrovirus (early transposon class) into intron 14 of the Tetratricopeptide repeat (TPR) domain 7 (Ttc7) gene. The insertion leads to reduced levels of wild-type Ttc7 transcripts in fsn mice and the insertion of an additional exon derived from the retrovirus into the majority of Ttc7 mRNAs. This disrupts one of the TPRs within TTC7 and may affect its interaction with an as-yet unidentified protein partner. The Ttc7 is expressed in multiple types of tissue including skin, kidney, spleen, and thymus, but is most abundant in germinal center B cells and hematopoietic stem cells, suggesting an important role in the development of immune system cells. Its role in immunologic and hematologic disorders should be either investigated.
Measuring Rotations of a Few Cross-Bridges in Skeletal Muscle
Authors: Borejdo Julian , Talent John , Akopova Irina
Published: July 2017

The ability to measure properties of a single cross-bridge in working muscle is important because it avoids averaging the signal from a large number of molecules and because it probes cross-bridges in their native crowded environment. Because the concentration of myosin in muscle is large, observing the kinetics of a single myosin molecule requires that the signal be collected from small volumes. The introduction of small observational volumes defined by diffraction-limited laser beams and confocal detection has made it possible to limit the observational volume to a femtoliter (10 15 liter). By restraining labeling to 1 fluorophore per 100 myosin molecules, we were able to follow the kinetics of approximately 400 cross-bridges. To reduce this number further, we used two-photon (2P) microscopy. The focal plane in which the laser power density was high enough to produce 2P absorption was thinner than in confocal microscopy. Using 2P microscopy, we were able to observe approximately 200 cross-bridges during contraction. The novel method of confocal total internal reflection (CTIR) provides a method to reduce the observational volume even further, to approximately 1 attoliter (10 18 liter), and to measure fluorescence with a high signal-to-noise (S/N) ratio. In this method, the observational volume is made shallow by illuminating the sample with an evanescent field produced by total internal reflection (TIR) of the incident laser beam. To guarantee the small lateral dimensions of the observational volume, a confocal aperture is inserted in the conjugate-image plane of the objective. With a 3.5-μm confocal aperture, we achieved a volume of 1.5 attoliter. Association-dissociation of the myosin head was probed with rhodamine attached at cys707 of the heavy chain of myosin. Signal was contributed by one to five fluorescent myosin molecules. Fluorescence decayed in a series of discrete steps, corresponding to bleaching of individual molecules of rhodamine. The S/N ratio was sufficiently large to make statistically significant comparisons from rigor and contracting myofibrils.
Influence of a Protein Concentrate from Amaranthus cruentus Seeds on Lipid Metabolism
Authors: Escudero N. L. , Zirulnik F. , Gomez N. N. , Mucciarelli S. I. , Mucciarelli S. I. , Giménez M. S.
Published: July 2017

It is widely known that elevated cholesterol and triglycerides levels favor the development of heart disease. In this paper we studied the effect of a protein concentrate from Amaranthus cruentus (Ac) on the lipid content in serum and liver tissue of male Wistar rats. The animals were separated into two groups, each group with 16 rats. The control diet had casein as protein source (CD), and the experimental one had Ac protein concentrate (PCAcD). The diets contained 1% cholesterol. Parameters of oxidative stress in liver with CD and PCAcD were also evaluated. No significant differences were observed in serum total cholesterol, whereas LDL decreased and HDL increased (P < 0.001), and the amount of triglycerides decreased in PCAcD as compared to CD. In liver, a decrease of total cholesterol and triglycerides (P < 0.001) was observed in the experimental group in relation to control. Fatty acid synthase (FAS) activity decreased significantly in the experimental group. The mRNA of HMG-CoA reductase did not change, and mRNA of FAS decreased in rat liver fed with PCAcD compared with CD. The excretion of total lipids in feces increased with PCAcD compared to CD (P < 0.001). The activity of reactive substances to thiobarbituric acid in liver showed no significant differences between the control and experimental diets. However, total glutathione and reduced glutathione increased in PCAcD compared to CD (P < 0.001). It can be concluded that PCAcD has a hypotriglyceridemic effect, affects the metabolism of liver lipids, and increases parameters of antioxidant protection in male Wistar rats.
T Cell Deficiency Leads to Liver Carcinogenesis in Azoxymethane-Treated Rats
Authors: Wu Bin , Ootani Akifumi , Iwakiri Ryuichi , Sakata Yasuhisa , Fujise Takehiro , Amemori Sadahiro , Yokoyama Fumie , Tsunada Seiji , Toda Shuji , Fujimoto Kazuma
Published: July 2017

There is an increasing amount of evidence suggesting that T cell deficiency contributes to tumor development. However, it is unclear whether T cell deficiency leads to liver and colon carcinogenesis. The aim of this study was to investigate the role of T cells on liver and colon carcinogenesis. Athymic F344/N Jcl-rnu/- (nu/nu) rats and euthymic F344/N Jcl-rnu/+ (nu/+) rats were administered the carcinogen azoxymethane (AOM) at a dose of 15 mg/kg body wt once a week for 2 weeks. At 48 weeks after the second carcinogen treatment, the rats were sacrificed, and livers and colons were examined. Apoptosis and cell proliferation were evaluated by DNA fragmentation and proliferating cell nuclear antigen assays, respectively. Wild-type p53 and members of the Jun and Fos oncogene families were detected by Western blotting. AOM treatment induced 100% liver tumor and 63.6% colon tumor incidence in T cell–deficient nu/nu rats, compared with 0% and 38.5% incidence in nu/+ rats. T cell deficiency promoted the inhibitory action of AOM on apoptosis in both liver and colon at 48 weeks. In contrast, T cell deficiency increased cell proliferation after AOM treatment in both tissues. Wild-type p53 was reduced in both tissues of T cell–deficient rats. AOM treatment induced c-Jun and c-Fos expressions in the liver but increased only Fos B in the colon, whereas T cell deficiency enhanced c-Jun overexpression in the liver. These results suggest that T cell deficiency leads to liver carcinogenesis partly by a reduction in wild-type p53 and increasing c-Jun expression in AOM-treated rats.
Functional Hypersplenism in Mice Induced by Adoptive Transfer of Syngeneic Spleen Cells
Authors: Salman Hertzel , Bessler Hanna , Bergman Michael , Fibach Eitan , Djaldetti Meir
Published: July 2017

Investigation of peripheral blood cell count alterations in cases with hypersplenism, and an understanding of the relationship between splenic function and hematopoietic cell production require suitable experimental animal models. Previously described methods are either traumatic or require surgical intervention. We suggest a relatively simple method for achievement of a state mimicking hypersplenism in mice by intraperitoneal inoculation of syngeneic spleen cells. Mice were inoculated intraperitoneally with 3 × 107 splenocytes suspended in 0.3 ml phosphate buffered saline (PBS). After 2 months, the inoculated animals showed a progressive decrease in the peripheral white blood cell (WBC) counts and hyperplastic bone marrow that persisted until the experimental end point (7 months). Five days after inoculation of splenocytes stained with carboxy-fluorescein diacetate succinimidyl ester (CFSE), the majority of the stained cells was present in the peritoneal cavity (33%) and in the liver (13%), whereas the percentage of stained cells in the peripheral blood and the spleen cell suspension was negligible. The mitogen response of the peripheral blood mononuclear cells (PBMC) from treated mice to concanavalin A (Con A) remained unaltered. Splenocyte-inoculated mice that were further splenectomized did not show leukocytosis after splenectomy, as was observed in animals in which the spleen was removed without any pretreatment. The lack of any signs of discomfort in animals from the study group, in comparison with the visibly ill appearance and even death of mice in which hypersplenism was achieved by repeated injections of methylcellulose (MC), which served as controls, favors the convenience of the method.
Obesity-Induced Hypertension Develops in Young Rats Independently of the Renin-Angiotensin-Aldosterone System
Authors: Smith Anita D. , Brands Michael W. , Wang Mong-Heng , Dorrance Anne M.
Published: July 2017

A correlation exists between obesity and hypertension. In the currently available models of diet-induced obesity, the treatment of rats with a high fat (HF) diet does not begin until adulthood. Our aim was to develop and characterize a model of pre-pubescent obesity-induced hypertension. Male Sprague-Dawley rats were fed a HF diet (35% fat) for 10 weeks, beginning at age 3 weeks. Blood pressure was measured by tail-cuff, and a terminal blood sample was obtained to measure fasting blood glucose, insulin, plasma renin, aldosterone, thiobarbitutic acid reactive substances (TBARS), and free 8-isoprostanes levels. The vascular reactivity in the aorta was assessed using a myograph. Blood pressure was increased in rats fed the HF diet (HF, 161 ± 2 mm Hg vs. control, 137 ± 2 mm Hg, P < 0.05). Blood glucose (HF, 155 ± 4 mg/dL vs. control, 123 ± 5 mg/dL, P < 0.05), insulin (HF, 232 ± 63 pM vs. control, 60 ± 11 pM, P < 0.05), TBARS (expressed as nM of malondialdehyde [MDA]/ml [HF, 1.8 ± 0.37 nM MDA/ml vs. control 1.05 ± 0.09 nM MDA/ml, P < 0.05]), and free 8-isoprostanes (HF, 229 ± 68 pg/ml vs. control, 112 ± 9 pg/ml, P < 0.05) levels were elevated in the HF diet group. Interestingly, plasma renin and aldosterone levels were not different between the groups. The maximum vasoconstriction to phenylephrine (10−4 M) was increased in the HF diet group (HF, 26.1 ± 1.5 mN vs. control 22.3 ± 1.2 mN, P < 0.05). In conclusion, pre-pubescent rats become hypertensive and have increased oxidative stress and enhanced vasoconstriction when fed a HF diet. Surprisingly, this occurs without the increase in renin or aldosterone levels seen in the adult models of diet-induced obesity.
Vagotonic Effects of Enkephalin are Not Mediated by Sympatholytic Mechanisms
Authors: Barlow Matthew A. , Deo Shekhar , Johnson Shavsha , Caffrey James L.
Published: July 2017

This study examined the hypothesis that vagotonic and sympatholytic effects of cardiac enkephalins are independently mediated by different receptors. A dose-response was constructed by administering the δ-receptor opioid methionine-enkephalin-arginine-phenylalanine (MEAP) by microdialysis into the interstitium of the canine sinoatrial node during vagal and sympathetic stimulation. The right cardiac sympathetic nerves were stimulated as they exited the stellate ganglion at frequencies selected to increase heart rate approximately 35 bpm. The right cervical vagus was stimulated at frequencies selected to produce a two-step decline in heart rate of 25 and 50 bpm. A six-step dose-response was constructed by recording heart rates during nerve stimulation as the dose of MEAP was increased between 0.05 pmol/min and 1.5 nmol/min. Vagal transmission improved during MEAP at 0.5 pmol/min. However, sympathetically mediated tachycardia was unaltered with any dose of MEAP. In Study 2, a similar dose-response was constructed with the κ-opioid receptor agonist trans(·)-3–4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)cyclohexyl]benzeneacetamide-HCI (U-50488H) to illustrate an independent sympatholytic effect and to verify its κ-receptor character. U-50488H gradually suppressed the sympathetic tachycardia, with a significant effect obtained only at the highest dose (1.5 nmol/min). U-50488H had no effect on vagally mediated bradycardia. Surprisingly, the sympatholytic effect was not reversed by withdrawing U-50488H or by the subsequent addition of the κ-antagonist 17,17′-(dichloropropylmethyl)-6,6′,7,7′-6,6′-imino-7,7′-binorphinan-3,4′,14,14′-tetroldihydrochloride (norBNI). Study 3 was conducted to determine whether the sympatholytic effect of U-50488H could be prevented by norBNI. NorBNI blocked the sympatholytic effect of the U50488H for 90 mins. When norBNI was discontinued afterward and U-50488H was continued alone, a sympatholytic effect emerged within 30 mins. Collectively these observations support the hypothesis that the vagotonic influence of MEAP is not dependent on a sympatholytic influence. Furthermore, the sympatholytic effect is mediated independently by κ-receptors. The sympatholytic effect of sustained κ-receptor stimulation appears to evolve gradually into a functional state not easily reversed.
Allyl Isothiocyanate and Its N-Acetylcysteine Conjugate Suppress Metastasis via Inhibition of Invasion, Migration, and Matrix Metalloproteinase-2/-9 Activities in SK-Hep1 Human Hepatoma Cells
Authors: Hwang Eun-Sun , Lee Hyong Joo
Published: July 2017

Cruciferous vegetables contain a series of relatively unique secondary metabolites of amino acids, called glucosinolates. Sinigrin, the predominant aliphatic glucosinolate in cruciferous vegetables, is hydrolyzed to yield allyl isothiocyanate (AITC), which, after absorption and metabolism in humans, is excreted in the urine as an N-acetyicysteine (NAC) conjugate. We have determined the inhibitory effects of AITC and its NAC conjugate on cell proliferation, the expression of matrix metalloproteinases (MMPs), adhesion, invasion, and migration in SK-Hep1 human hepatoma cells. Our results demonstrate that AITC and NAC-AITC suppress SK-Hep1 cell proliferation in a dose-dependent manner; by 25% and 30% for 10 μM AITC and 10 μM NAC-AITC, respectively. We examined the influence of AITC and NAC-AITC on the gene expression of MMPs and tissue inhibitors of metalloproteinase (TIMPs). Gelatin zymography also revealed a significant downregulation of MMP-2/-9 expression in SK-Hep1 cells treated with 0.1–5 μM AITC and NAC-AITC compared with controls. Reverse transcriptase polymerase chain reaction revealed dose-dependent decreases in MMP-2/-9 messenger RNA levels in both AITC-treated and NAC-AITC–treated cells. TIMP-1/-2 activities were unaffected by treatment with AITC or NAC-AITC in our experiments. NAC-AITC inhibited cancer cell adhesion and invasion much more potently than its parent compound. NAC-AITC at 5 μM caused excellent inhibition of cell migration for 48 hrs. These results demonstrate the potential of AITC and NAC-AITC as chemopreventive agents.
Fructose-Fed Rat Hearts are Protected Against Ischemia-Reperfusion Injury
Authors: Faure Marie Joyeux , Rossini Eliane , Ribuot Christophe , Faure Patrice
Published: July 2017

High fructose-fed (HFF) rat model is known to develop the insulin-resistant syndrome with a very similar metabolic profile to the human X syndrome. Such metabolic modifications have been associated with a high incidence of cardiovascular disease. The role of free radical attack in diabetes mellitus and its cardiovascular complications have been abundantly documented. The present study examined the susceptibility to myocardial ischemic injury and the involvement of free radical attack and/or protection in the metabolic disorders of high FF rats. Rats were divided into two experimental groups that received diet for 4 weeks: a control group (C, n = 28) receiving a standard diet and a HFF group (FF, n = 28), in which 58% of the total carbohydrate was fructose. The euglycemic clamp technique was performed to assess insulin resistance. For the ischemia-reperfusion procedure, rat hearts were isolated and perfused at constant pressure before they were subjected to a 30-min occlusion of the left coronary artery followed by 120 mins of reperfusion. Hemodynamic parameters were measured throughout the protocol. Infarct-to-risk ratio (I/R) was assessed at the end of the protocol by 2,3,4-triphenyltetrazolium chloride staining and planimetric analysis. Lipid peroxidation, antioxidant enzyme activity, level of vitamin E, and trace element status were measured in blood samples from both groups. Rats of the FF group developed an insulin resistance indicated by the glucose infusion rate, which was decreased by 47%. Infarct size was significantly reduced in rats from the FF group (19.9% ± 6.6%) compared to rats from the control group (34.6% ± 4.9%), and cardiac functional recovery at reperfusion was improved in the FF group. Lipid peroxidation and oxidative stress were higher in the FF group, as indicated by higher malonedialdehyde level, whereas plasma vitamin E/triacylglycerol ratio was also enhanced in this group. This study indicates that fructose feeding affords protection against in vitro ischemia-reperfusion injury, potentially implicating vitamin E.
Antioxidant and Lysosomotropic Properties of Acute d-Propranolol Underlies Its Cardioprotection of Postischemic Hearts from Moderate Iron-Overloaded Rats
Authors: Kramer Jay H. , Murthi Sarah B. , Wise Robert M. , Mak I-Tong , Weglicki William B.
Published: July 2017

The benefits of acute d-propranolol (d-Pro, non–β-adrenergic receptor blocker) pretreatment against enhanced ischemia/reperfusion (I/R) injury of hearts from moderate iron-overloaded rats were examined. Perfused hearts from iron-dextran-treated rats (450 mg/kg/week for 3 weeks, intraperitoneal administration) exhibited normal control function, despite iron treatment that elevated plasma iron and conjugated diene levels by 8.1-and 2.5-fold, respectively. However, these hearts were more susceptible to 25 mins of global I/R stress compared with nonloaded hearts; the coronary flow rate, aortic output, cardiac work, left ventricular systolic pressure, positive differential left ventricular pressure (dP/dt), and left ventricular developed pressure displayed 38%, 60%, 55%, 13%, 41%, and 15% lower recoveries, respectively, and a 6.5-fold increase in left ventricular end-diastolic pressure. Postischemic hearts from iron-loaded rats also exhibited 5.6-, 3.48-, 2.43-, and 3.45-fold increases in total effluent iron content, conjugated diene levels, lactate dehydrogenase (LDH) activity, and lysosomal N-acetyl-β-glucosaminidase (NAGA) activity, respectively, compared with similarly stressed nonloaded hearts. A comparison of detection time profiles during reperfusion suggests that most of the oxidative injury (conjugated diene) in hearts from iron-loaded rats occurred at later times of reperfusion (8.5-15 mins), and this corresponded with heightened tissue iron and NAGA release, d-Pro (2 μM infused for 30 mins) pretreatment before ischemia protected all parameters compared with the untreated iron-loaded group; pressure indices improved 1.2- to 1.6-fold, flow parameters improved 1.70- to 2.96-fold, cardiac work improved 2.87-fold, and end-diastolic pressure was reduced 56%. d-Pro lowered total release of tissue iron, conjugated diene content, LDH activity, and NAGA activity 4.59-, 2.55-, 3.04-, and 4.14-fold, respectively, in the effluent of l/R hearts from the iron-loaded group. These findings suggest that the enhanced postischemic dysfunction and tissue injury of hearts from iron-loaded rats was caused by excessive iron-catalyzed free radical stress, and that the membrane antioxidant properties of d-Pro and its stabilization of sequestered lysosomal iron by d-Pro may contribute to the cardioprotective actions of d-Pro.
Choline Transport for Phospholipid Synthesis
Authors: Michel Vera , Yuan Zongfei , Ramsubir Shobha , Bakovic Marica
Published: July 2017

Choline is an essential nutrient for all cells because it plays a role in the synthesis of the membrane phospholipid components of the cell membranes, as a methyl-group donor in methionine metabolism as well as in the synthesis of the neurotransmitter acetylcholine. Choline deficiency affects the expression of genes involved in cell proliferation, differentiation, and apoptosis, and it has been associated with liver dysfunction and cancer. Abnormal choline transport and metabolism have been implicated in a number of neurodegenerative disorders such as Alzheimer's and Parkinson's disease. Therefore, the study of choline transport and the characteristics of choline transporters are of central importance to understanding the mechanisms that underlie membrane integrity and cell signaling in such disorders. Kinetic studies with radiolabeled choline and inhibitors distinguish three systems for choline transport: (i) low-affinity facilitated diffusion, (ii) high-affinity, Na+-dependent transport, and (iii) intermediate-affinity, Na+-independent transport. It is only recently, however, that the proteins having transport characteristics of at least one of these systems have been identified. They include (i) polyspecific organic cation transporters (OCTs) with low affinity for choline, (ii) high-affinity choline transporters (CHT1s), and (iii) intermediate-affinity choline transporter-like (CTL1) proteins. CHT1 and CTL1 but not OCT transporters are selectively inhibited with hemicholinium-3 and essentially display characteristics of specialized transporters for targeted choline metabolism. CHT1 is abundant in neurons and almost exclusively supplies choline for acetylcholine synthesis. The focus here is more on newly-discovered CTL1 choline transporters. They are expressed in different organisms and cell types, apparently not for the biosynthesis of acetylcholine but for the production of the most abundant metabolite of choline, the membrane lipid phosphatidylcholine.
Global Gene Expression in Mouse Vaginae Exposed to Diethylstilbestrol at Different Ages
Authors: Suzuki Atsuko , Watanabe Hajime , Mizutani Takeshi , Sato Tomomi , Ohta Yasuhiko , Iguchi Taisen
Published: July 2017

Estrogens regulate proliferation and differentiation of cells in target organs such as the female reproductive tract. In mature mice, estrogens stimulate cell proliferation, whereas ovariectomy results in atrophy of the female reproductive tract. In contrast, perinatal exposure to estrogens, including diethylstilbestrol (DES), induces persistent, ovary-independent vaginal stratification and cervico-vaginal tumors later in life. These effects are due to altered cell fate following DES exposure during a critical developmental period. The detailed mechanisms underlying the reversible and irreversible cell proliferation in vaginae induced by DES at different ages has not been clarified. Therefore, we examined differences in gene expression pattern using DNA microarray analysis in mouse vaginae 6 hrs after a single injection of 2 μg DES per gram of body weight, and proliferation of vaginal epithelial and stromal cells 24 hrs after the injection at postnatal days (PNDs) 0, 5, 20, and 70. After DES stimulation, vaginal epithelial and stromal cells showed cell proliferation at PNDs 20 and 70, and at PNDs 0 and 5, respectively. DNA microarray analysis exhibited 54 DES-induced genes and 9 DES-repressed genes in vaginae at PND 0, whereas more than 200 DES-induced genes were found in vaginae at PNDs 5 and 20, and 350 genes at PND 70. Clustering analysis of DES-induced genes in the vaginae at different ages revealed that genes induced by DES at PND 5 were closer to the adult type than that of PND 0. Genes related to keratinocyte differentiation, such as Gadd45α, p21, 14–3–3 sigma, small proline-rich protein 2f (Sprr2f), and Krupple-like factor 4 (Klf4), were induced by DES. The number of DES-induced genes during the critical period, PND 0, was smaller than those found after the critical period. These results give insight toward understanding the molecular mechanisms underlying the critical period in mouse vaginae.
Industry's Challenge to Academia: Changing the Bench to Bedside Paradigm
Authors: Fluckiger Stephen L.
Published: July 2017

The need for interdisciplinary collaboration is arising as a result of accelerating advances in basic science, including massive research and development funding by both government and industry, which has spurred the so-called “nanotechnology revolution” and developments at the intersection of the life and physical sciences, increasing emphasis by federal research funding agencies on interdisciplinary and inter-institutional research and by market influences. A number of barriers presently limit the interaction between academics and industry, including the typically very time-consuming and slow pace of technology transfer, which is compounded in the case of interdisciplinary and inter-institutional licensing, as well as the natural, and understandable, antipathies that exist between academia and industry as a result of their differing missions and approaches to scientific discovery. Moreover, if mechanisms are not in place at the outset of an inter-university collaboration, then the transition of inventions to clinical applications can be fraught with additional complexities and barriers. Policies suggested by the National Nanotechnology Initiative offer a number of ideas for overcoming barriers to multidisciplinary and inter-institutional research and illustrate some of the ways in which academia can structure partnerships with industry that will not only provide needed funding for multidisciplinary and inter-institutional biomedical research in an era of diminishing federal resources, but may permit academia, on the one hand, and industry, on the other, to benefit from the strengths provided by the other without compromising either academia's or industry's basic missions.
Retinoblastoma Tumor Suppressor: Where Cancer Meets the Cell Cycle
Authors: Knudsen Erik S. , Knudsen Karen E.
Published: July 2017

The retinoblastoma tumor suppressor gene, Rb, was the first tumor suppressor identified and plays a fundamental role in regulation of progression through the cell cycle. This review details facets of RB protein function in cell cycle control and focuses on specific questions that remain intensive areas of investigation.
Treatment of Viral and Neoplastic Diseases with Double-Stranded RNA Derivatives and Other New Agents
Authors: Ambrus Julian L. , Chadha Kailash C. , Islam Anwarul , Akhter Selina , Ambrus Julian L.
Published: July 2017

Many attempts have been made to inhibit viral and neoplastic diseases by targeting the RNA system. The pathophysiologic significance of the microRNA system and the therapeutic potential of its manipulation are discussed. Studies of double-stranded RNA derivatives are reviewed. The therapeutic potential of one of these compounds, polyl: MPC, is emphasized. Studies of other related antiviral and antineoplastic agents are discussed, including 2′-deoxyoligocytidilates and telomerase inhibitors.
Central Effects of Ghrelin on Serum Growth Hormone and Morphology of Pituitary Somatotropes in Rats
Authors: Stevanović D. , Milošević V. , Nešić D. , Ajdžanović V. , Starčević V. , Severs W. B.
Published: July 2017

Ghrelin, an endogenous ligand for the growth hormone (GH) secretagogue receptor, was originally purified from rat stomach; subsequently, ghrelin neurons were found in the arcuate nuclei of rats. Central effects of the peptide on GH release, however, remain to be clarified. The aim of the present study was to determine the morphologic features of GH-producing pituicytes and serum GH concentration after central administration of ghrelin. Five injections of rat ghrelin or phosphate-buffered saline (PBS; n = 10 rats/group) were given every 24 hrs (1 μg of ghrelin in 5 μl of PBS) into the lateral cerebral ventricle of male rats. Significant (P < 0.05) increases in absolute and relative pituitary weights occurred in ghrelin-treated rats versus controls (58% and 41%, respectively). Morphometric parameters (i.e., the volume of GH cells, volume of their nuclei, and volume density) all significantly (P < 0.05) increased by 17%, 18%, and 19%, respectively, in the ghrelin-treated group versus controls. Terminal serum concentration of GH was significantly (P < 0.05) increased by 15% with ghrelin treatment. The results clearly document that daily nanomolar doses of ghrelin into the lateral cerebral ventricle stimulate GH cell proliferation and promote GH release. Thus, achieving pharmacologic control of central ghrelin receptors is a promising modality to modulate the actions of GH.
Dose-Different Effects of Orexin-A on the Renal Sympathetic Nerve and Blood Pressure in Urethane-Anesthetized Rats
Authors: Tanida Mamoru , Niijima Akira , Shen Jiao , Yamada Shigeru , Sawai Hajime , Fukuda Yutaka , Nagai Katsuya
Published: July 2017

Previous studies have demonstrated that central injection of orexin-A affects renal sympathetic nerve activity (RSNA) and blood pressure (BP) in both anesthetized and unanesthetized rats. In the present study, we examined, using urethane-anesthetized rats, the dose-dependent effects of intravenous (iv) or intralateral cerebral ventricular (LCV) injection of various doses of orexin-A on RSNA and BP. We found that injection of a low dose of orexin-A (10 ng iv or 0.01 ng LCV) suppressed RSNA and BP significantly. Conversely, a high dose (1000 ng iv or 10 ng LCV) of orexin-A elevated both RSNA and BP significantly. Pretreatment with either iv or LCV injection of thioperamide, a histaminergic H3-receptor antagonist, eliminated the effects of a low dose of orexin-A on both RSNA and BP. Both iv and LCV injection of diphenhydramine, a histaminergic H1-receptor antagonist, abolished the effects of a high dose of orexin-A on RSNA and BP. Furthermore, bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN) abolished the effects of both low and high doses of orexin-A on RSNA and BP. These findings suggest that orexin-A affects RSNA and BP in a dose-dependent manner and that the SCN and histaminergic nerve may be involved in the dose-different effects of orexin-A in rats.
Effects of Histamine on Immunophenotype and Notch Signaling in Human HL-60 Leukemia Cells
Authors: Yu Li Mei , Chen Dai Xiong , Zhou Qi Xin , Fang Ning , Liu Zu Lin
Published: July 2017

Surface molecules are important biomarkers for cell proliferation and differentiation and play important roles in cell function and cell interaction. Notch is a transmembrane receptor that regulates developmental processes and cell-fate decision. Histamine is used as an adjunct to immunotherapy in myelogenous leukemia, and regulates hematopoietic cell development. Thus, we investigated the effects of histamine on immunophenotype and Notch signaling in human HL-60 leukemia cells. Histamine (0.1–10 μM) inhibited the colony-forming efficiency of HL-60 cells in a dose-dependent fashion and shifted the growth curve to the right. HL-60 cells were treated with histamine 0.1–1.0 μM for 6 days, and surface molecules were analyzed by flow cytometry. Histamine decreased CD49d positive cells by 74% while increasing CD31 positive cells by 53% as compared to controls. Histamine did not affect the expression of CD11b, CD14, CD34, CD44, CD54, CD49e, and CD62L. To examine Notch signaling in histamine-induced immunophenotype alterations in HL-60 cells, total RNA was isolated, purified, and subjected to real-time RT-PCR analysis. The expressions of Notch1, Notch4, the ligands Jagged1, Delta4, and the downstream hairy enhancer of split 1 gene (HES1) were not significantly altered by histamine. In summary, this study demonstrated that histamine inhibited HL-60 cell growth and regulated immunophenotypes of CD49d and CD31. These effects are not mediated through the Notch signaling.
Paracrine VEGF/VE-Cadherin Action on Ovarian Cancer Permeability
Authors: Hu Limin , Ferrara Napoleone , Jaffe Robert B.
Published: July 2017

Ascites formation associated with neoplasms is most likely due to increased vascular permeability, a process in which vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) plays a pivotal role. We hypothesized that tumor-derived VEGF/VPF modulates ascites formation through a paracrine effect on both tumor and peritoneal vessels. We investigated human vascular endothelial permeability using a newly developed dual-chamber permeability assay by co-culturing human umbilical vein cells with and without ovarian cancer cell lines (OVCAR-3, Hey-A8, and OCC-1) in the presence or absence of a human VEGF monoclonal antibody and VE-cadherin function–blocking antibody. This method permits determination of mechanisms by which substances released from neoplasms and other sources of vascular endothelial cell secretagogues modulate vascular permeability and likely other pathologic states.