bluuebunny/crossref_metadata_2025 huggingface dataset:
Nitrogen Dioxide Air Pollution near Ambient Levels is an Atherogenic Risk Primarily in Obese Subjects: A Brief Communication
Authors: Takano Hirohisa , Yanagisawa Rie , Inoue Ken-ichiro , Shimada Akinori , Ichinose Takamichi , Sadakane Kaori , Yoshino Shin , Yamaki Kouya , Morita Masatoshi , Yoshikawa Toshikazu
Published: July 2017

Ambient exposure to nitrogen dioxide, a critical air pollutant in developed countries, is positively associated with cardiovascular mortality and morbidity. Although its cardiovascular effects are predominantly shown in patients with high risk of atherogenesis, no studies have elucidated whether daily exposure to nitrogen dioxide air pollution enhances atherogenic metabolisms, primarily in obese subjects who are susceptible to atherogenesis and subsequent cardiovascular diseases. We used male Otsuka Long-Evans Tokushima Fatty (OLETF) rats as obese subjects and Long-Evans Tokushima (LETO) rats as nonobese controls. The animals were continuously exposed to nitrogen dioxide at a concentration of 0, 0.16, 0.8, or 4.0 ppm from 8 weeks of age through 32 weeks. At 40 weeks of age, levels of body weight, triglyceride, and total cholesterol were significantly greater in the OLETF rats than in the LETO rats. A ratio of high-density lipoprotein (HDL) to total cholesterol was significantly smaller in the former than in the latter. In the LETO rats, nitrogen dioxide exposure significantly decreased only the levels of HDL as compared with clean air exposure. In the OLETF rats, however, nitrogen dioxide exposure at a concentration of 0.16 ppm significantly elevated triglyceride concentration and decreased the ratio of HDL to total cholesterol as well as the levels of HDL. Nitrogen dioxide air pollution near ambient levels is an atherogenic risk primarily in obese subjects.
Endocrine Disruption by Cadmium, a Common Environmental Toxicant with Paradoxical Effects on Reproduction
Authors: Henson Michael C. , Chedrese P. Jorge
Published: July 2017

Cadmium (Cd2+) is a common environmental pollutant and a major constituent of tobacco smoke. Exposure to this heavy metal, which has no known beneficial physiological role, has been linked to a wide range of detrimental effects on mammalian reproduction. Intriguingly, depending on the identity of the steroidogenic tissue involved and the dosage used, it has been reported to either enhance or inhibit the biosynthesis of progesterone, a hormone that is inexorably linked to both normal ovarian cyclicity and the maintenance of pregnancy. Thus, Cd2+has been shown to exert significant effects on ovarian and reproductive tract morphology, with extremely low dosages reported to stimulate ovarian luteal progesterone biosynthesis and high dosages inhibiting it. In addition, Cd2+exposure during human pregnancy has been linked to decreased birth weights and premature birth, with the enhanced levels of placental Cd2+resulting from maternal exposure to industrial wastes or tobacco smoke being associated with decreased progesterone biosynthesis by the placental trophoblast. The stimulatory effects of Cd2+on ovarian progesterone synthesis, as revealed by the results of studies using stable porcine granulosa cells, appear centered on the enhanced conversion of cholesterol to pregnenolone by the cytochrome P450 side chain cleavage (P450scc). However, in the placenta, the Cd2+-induced decline in progesterone synthesis is commensurate with a decrease in P450scc. Additionally, placental low-density lipoprotein receptor (LDL-R) mRNA declines in response to Cd2+exposure, suggesting an inhibition in the pathway that provides cholesterol precursor from the maternal peripheral circulation. Potential mechanisms by which Cd2+may affect steroidogenesis include interference with the DNA binding zinc (Zn2+)-finger motif through the substitution of Cd2+for Zn2+or by taking on the role of an endocrine disrupting chemical (EDC) that could mimic or inhibit the actions of endogenous estrogens. Divergent, tissue-specific (ovary vs. placenta) effects of Cd2+also cannot be ruled out. Therefore, in consideration of the data currently available and in light of the potentially serious consequences of environmental Cd2+exposure to human reproduction, we propose that priority should be given to studies dedicated to further elucidating the mechanisms involved.
Biological Roles of Alpha-Fetoprotein During Pregnancy and Perinatal Development
Authors: Mizejewski Gerald J.
Published: July 2017

The use of alpha-fetoprotein (AFP) as a serum marker in cancer actually predates its employment in the detection of congenital defects; however, the latter use of AFP as a fetal defect marker has propelled its clinical utilization. Although the serum-marker capacity of AFP has long been exploited, less is known of the biological activities of this oncofetal protein during fetal and perinatal development. In the present review, the biological activities of AFP are discussed in light of this glycoprotein's presence in various biological fluid compartments: embryonic and fetal tissues, serum, urine, and reproductive fluids. After a review of the histochemical detection of AFP in various cells and tissues during development, AFP concentrations within various biological fluids were discussed in the context of gestational age and anatomic location. Discussion follows concerning the relationships and roles of AFP in developmental events such as erthyropoiesis, histogenesis/organogenesis, and ligand binding and in developmental disorders such as hypothyroidism, folate deficiencies, and acquired immunodeficiency disorder (AIDS). Based on its association with so many types of birth defects, malformations, and congenital anomalies, AFP can be viewed as a molecular “troubleshooter” until signal transduction pathways are established during pregnancy and prenatal development. The review concludes with a discussion of the place of AFP in the rapidly expanding field of proteomics.
Senescent B Lymphopoiesis is Balanced in Suppressive Homeostasis: Decrease in Interleukin-7 and Transforming Growth Factor-β Levels in Stromal Cells of Senescence-Accelerated Mice
Authors: Tsuboi Isao , Morimoto Kohji , Hirabayashi Yoko , Li Guang-Xun , Aizawa Shin , Mori Kazuhiro J. , Kanno Jun , Inoue Tohru
Published: July 2017

The suppression of the B cell population during senescence has been considered to be due to the suppression of interleukin-7 (IL-7) production and responsiveness to IL-7; however, the upregulation of transforming growth factor-β (TGF-β) was found to contribute to B cell suppression. To investigate the mechanism of this suppression based on the interrelationship between IL-7 and TGF-β during senescence, senescence-accelerated mice (SAMs), the mouse model of aging, were used in this study to elucidate the mechanisms of B lymphopoietic suppression during aging. Similar to regular senescent mice, SAMs showed a decrease in the number of IL-7–responding B cell progenitors (i.e., colony-forming unit pre-B [CFU-pre-B] cells in the femoral bone marrow [BM]). A co-culture system of B lymphocytes and stromal cells that the authors established showed a significantly lower number of CFU-pre-B cells harvested when BM cells were co-cultured with senescent stromal cells than when they were co-cultured with young stromal cells. Interestingly, cells harvested from a senescent stroma and those from the control culture without stromal cells were higher in number than those harvested from a young stroma, thereby implying that an altered senescent stromal cell is unable to maintain self-renewal of the stem cell compartment. Because TGF-β is supposed to suppress the proliferative capacity of pro-B/pre-B cells, we added a neutralizing anti-TGF-β antibody to the co-culture system with a pro-B/pre-B cell-rich population to determine whether such suppression may be rescued. However, unexpectedly, any rescue was not observed and the number of CFU-pre-B cells remained unchanged when BM cells were co-cultured with senescent stromal cells compared with the co-culture with young stromal cells, which essentially showed an increase in the number of CFU-pre-B cells (P < 0.001 in 5 μg/ml). Furthermore, TGF-β protein level in the supernatant of cultured senescent stroma cells was evaluated by enzyme-linked immunoabsorbent assay, but surprisingly, it was found that TGF-β concentration was significantly lower than that of cultured young stromal cells. Thus, TGF-β activity was assumed to decline particularly in a senescent stroma, which means a distinct difference between the senescent suppression of B lymphopoiesis and secondary B lymphocytopenia. Concerning proliferative signaling, on the other hand, the level of IL-7 gene expression in cells from freshly isolated BM decreased significantly with age. Therefore, the acceleration of proliferative signaling and the deceleration of suppressive signaling may both be altered and weakened in a senescent stroma (i.e., homeosupression).
Compensatory Growth of Adipose Tissue After Partial Lipectomy: Involvement of Serum Factors
Authors: Hausman Dorothy B. , Lu Jie , Ryan Donna H. , Flatt William P. , Harris Ruth B. S.
Published: July 2017

The regulation of body weight/fat was studied by investigating mechanisms for compensatory adipose tissue growth after removal of bilateral epididymal fat pads from male adult Wistar rats. Food intake during the first 4 weeks and energy expenditure on Days 8-10 postsurgery were not different between lipectomized and sham operated rats. During Days 29–31 post surgery, a small (2.4%) but significant (P < 0.05) increase in heat production per metabolic body size was detected in lipectomized as compared with sham operated rats. The carcass composition of lipectomized and sham operated rats was not significantly different 16 weeks after surgery. The compensatory growth was fat pad–specific: mesenteric, retroperitoneal, and inguinal fat pads, but not perirenal fat pads, were heavier in lipectomized rats than in sham operated rats as early as 4 weeks postsurgery. Examination of fat cell size distribution in the compensating pads indicated a shift toward larger cells in retroperitoneal fat, but not in inguinal fat of lipectomized as compared with sham operated rats. Serum from lipectomized rats, but not media conditioned by exposure to retroperitoneal fat pads from lipectomized rats, stimulated proliferation of preadipocytes in vitro more than that from sham operated rats. Thus, compensatory adipose tissue growth after lipectomy may be mediated, in part, by blood-borne factors that are derived from tissues other than adipose tissue.
Vitamin A Requirement for Early Cardiovascular Morphogenesis Specification in the Vertebrate Embryo: Insights from the Avian Embryo
Authors: Zile Maija H.
Published: July 2017

Vitamin A is required throughout the life cycle, including crucial stages of embryonic and fetal development. With the identification of retinoic acid-specific nuclear transcription factors, the retinoid receptors, considerable advances have been made in understanding the molecular function of vitamin A. The requirement for vitamin A during early embryogenesis has successfully been examined in the vitamin A-deficient avian embryo during neurulation, when in the vertebrates crucial developmental decisions take place. These studies revealed that retinoic acid is essential during these early stages of embryogenesis for the initiation of organogenesis (i.e., formation of the heart). If retinoic acid is not present at this time, abnormal development ensues, leading to early embryonic death. Though the initial insult of the absence of vitamin A appears to be on the specification of cardiovascular tissues, subsequently all development is adversely affected and the embryo dies. Molecular and functional studies revealed that retinoic acid regulates the expression of the cardiogenic transcription factor GATA-4 and several heart asymmetry genes, which explains why the heart position is random in vitamin A-deficient quail embryos. During the crucial retinoic acid-requiring developmental window, retinoic acid transduces its signals to genes for heart morphogenesis via the receptors RARα2, RARγ, and RXRα. Elucidation of the function of vitamin A during early embryonic development may lead to a better understanding of the cardiovascular birth defects prevalent in the Western world.
Oxidative Stress Plays an Important Role in the Pathogenesis of Drug-Induced Retinopathy
Authors: Toler Steven M.
Published: July 2017

Several pharmaceutical agents have been associated with rare but serious retinopathies, some resulting in blindness. Little is known of the mechanism(s) that produce these injuries. Mechanisms proposed thus far have not been embraced by the medical and scientific communities. However, preclinical and clinical data indicate that oxidative stress may contribute substantially to iatrogenic retinal disease. Retinal oxidative stress may be precipitated by the interaction of putative retinal toxins with the ocular redox system. The retina, replete with cytochromes P450 and myeloperoxidase, may serve to activate xenobiotics to oxidants, resulting in ocular injury. These activated agents may directly form retinal adducts or may diminish ocular reduced glutathione concentrations. Data are reviewed that suggest that indomethacin, tamoxifen, thioridazine, and chloroquine all produce retinopathies via a common mechanism—they produce ocular oxidative stress.
Polyenoic Fatty Acid Ratios Alter Fibroblast Collagen Production Via PGE2 and PGE Receptor Subtype Response
Authors: Jia Yi , Turek John J.
Published: July 2017

Previous experiments have shown that dietary n-6 and n-3 polyenoic fatty acids (PFA) have different effects on collagen production, a process that may be related to the formation of prostaglandins (PG). This study tested the hypothesis that fibroblast collagen production could be regulated by different n-6:n-3 PFA ratios and that the effects were mediated by PGE2 and altered signaling via the different PGE receptor subtypes. Compared to a bovine serum albumin control, eicosapentaenoic acid (EPA; 20:5 n-3) treated cells significantly (P < 0.05) increased both collagen production and collagen as a percentage of total cellular protein (C-PTP), but arachidonic acid (AA; 20:4 n-6) reduced collagen production and C-PTP. As the amount of AA decreased and that of EPA increased, collagen production and C-PTP increased, especially when ratio of n-6:n-3 PFA was less than 1:1. C-PTP was significantly correlated with the amount of PGE2 in the medium. AA- or EPA-treated cells produced similar C-PTP when incubated with 10−6 M indomethacin, a cyclooxygenase inhibitor. Addition of exogenous PGE2 to cell cultures treated with 10−6 M indomethacin for 48 hrs decreased C-PTP in both AA and EPA groups. Decreased C-PTP was observed in AA-treated cells exposed to EP1, EP2, and EP4 PGE receptor agonists and in EPA-treated cells exposed to EP2 and EP4 agonists. AA-treated cell responded to activators of cyclic adenosine monophosphate and protein kinase C by decreasing C-PTP, but EPA-treated cells were unresponsive. In conclusion, collagen production in 3T3-Swiss fibroblasts induced by different n-6:n-3 PFA ratios was correlated with PGE2 production and altered responsiveness and signaling via the different PGE receptor subtypes.
Intermittent Hypoxic Training Protects Canine Myocardium from Infarction
Authors: Zong Pu , Setty Srinath , Sun Wei , Martinez Rodolfo , Tune Johnathan D. , Ehrenburg Igor V. , Tkatchouk Elena N. , Mallet Robert T. , Downey H. Fred
Published: July 2017

This investigation examined cardiac protective effects of normobaric intermittent hypoxia training. Six dogs underwent intermittent hypoxic training for 20 consecutive days in a normobaric chamber ventilated intermittently with N2 to reduce fraction of inspired oxygen (Fio2) to 9.5%–10%. Hypoxic periods, initially 5 mins and increasing to 10 mins, were followed by 4-min normoxic periods. This hypoxia-normoxia protocol was repeated, initially 5 times and increasing to 8 times. The dogs showed no discomfort during intermittent hypoxic training. After 20 days of hypoxic training, the resistance of ventricular myocardium to infarction was assessed in an acute experiment. The left anterior descending (LAD) coronary artery was occluded for 60 mins and then reperfused for 5 hrs. At 30 mins of LAD occlusion, radioactive microspheres were injected through a left atrial catheter to assess coronary collateral blood flow into the ischemic region. After 5 hrs reperfusion, the heart was dyed to delineate the area at risk (AAR) of infarction and stained with triphenyl tetrazolium chloride to identify infarcted myocardium. During LAD occlusion and reperfusion, systemic hemodynamics and global left ventricular function were stable. Infarction was not detected in 4 hearts and was 1.6% of AAR in the other 2 hearts. In contrast, 6 dogs sham-trained in a chamber ventilated with compressed air and 5 untrained dogs subjected to the same LAD occlusion/reperfusion protocol had infarcts of 36.8% ± 5.8% and 35.2% ± 9.5% of the AAR, respectively. The reduction in infarct size of four of the six hypoxia-trained dogs could not be explained by enhanced collateral blood flow to the AAR. Hypoxia-trained dogs had no ventricular tachycardia or ventricular fibrillation. Three sham-trained dogs had ventricular tachycardia and two had ventricular fibrillation. Three untrained dogs had ventricular fibrillation. In conclusion, intermittent hypoxic training protects canine myocardium from infarction and life-threatening arrhythmias during coronary artery occlusion and reperfusion. The mechanism responsible for this potent cardioprotection merits further study.
Postnatal Environment Affects Behavior of Adult Transgenic Mice
Authors: Crews David , Fuller Trevon , Mirasol Elsa G. , Pfaff Donald W. , Ogawa Sonoko
Published: July 2017

Behavioral phenotypes of knockout mice are often interpreted as the effects of the absence of the gene product on adult behavior, yet behavioral differences among genotypes may be exaggerated or blurred by the postnatal environment. For example, mice develop in litters of varying sex ratios and genotypes, and it is possible that some of these behavioral differences may result from the composition of the litter. To determine whether these factors might play a role in the development of the behavioral characteristics that have become diagnostic of the knockout, offspring of parents heterozygous for a null mutation of estrogen receptor α (ERKO) were sexed and genotyped within 2 days of birth. Litters were then reconstituted, forming same-sex litters of equal numbers of ERKO and wild-type (WT) individuals that were tested in a standard resident-intruder paradigm. In this manner the effect of genotype would be evident without the potential confound of the presence of the opposite sex in the litter. Behavioral differences between the genotypes were more sharply defined than reported previously. ERKO females displayed only aggressive behavior whereas their WT littermates displayed only mounting behavior; both aggression and mounting behavior were greatly reduced in ERKO males. These data suggest that the postnatal environment such as litter composition may influence the development of sociosexual behaviors in ERKO mice.
DNA Methylation, Cancer Susceptibility, and Nutrient Interactions
Authors: Davis Cindy D. , Uthus Eric O.
Published: July 2017

DNA methylation is an important epigenetic mechanism of transcriptional control. DNA methylation plays an essential role in maintaining cellular function, and changes in methylation patterns may contribute to the development of cancer. Aberrant methylation of DNA (global hypomethylation accompanied by region-specific hypermethylation) is frequently found in tumor cells. Global hypomethylation can result in chromosome instability, and hypermethylation has been associated with the inaction of tumor suppressor genes. Preclinical and clinical studies suggest that part of the cancer-protective effects associated with several bioactive food components may relate to DNA methylation patterns. Dietary factors that are involved in one-carbon metabolism provide the most compelling data for the interaction of nutrients and DNA methylation because they influence the supply of methyl groups, and therefore the biochemical pathways of methylation processes. These nutrients include folate, vitamin B12, vitamin B6, methionine, and choline. However, looking at individual nutrients may be too simplistic. Dietary methyl (folate, choline, and methionine) deficiency in combination causes decreased tissue S-adenosylmethionine, global DNA hypomethylation, hepatic steatosis, cirrhosis, and ultimately hepatic tumorigenesis in rodents in the absence of carcinogen treatment. Other dietary components such as vitamin B12, alcohol, and selenium may modify the response to inadequate dietary folate.
Dietary Corn Oil Promotes Colon Cancer by Inhibiting Mitochondria-Dependent Apoptosis in Azoxymethane-Treated Rats
Authors: Wu Bin , Iwakiri Ryuichi , Ootani Akifumi , Tsunada Seiji , Fujise Takehiro , Sakata Yasuhisa , Sakata Hiroyuki , Toda Shuji , Fujimoto Kazuma
Published: July 2017

How dietary corn oil is involved in colon carcinogenesis and cancer development is poorly understood. The aim of this study was to investigate whether long-term dietary corn oil promotes colon cancer by inhibiting the tumor suppressor gene p53-mediated mitochondria-dependent apoptosis in azoxymethane (AOM)-treated rats. Male Sprague-Dawley rats were injected with AOM or with saline and fed on a basal diet or basal diet supplemented with 10% corn oil for 48 weeks. Colonic aberrant crypt foci (ACF) and tumors, including adenomas and carcinomas, were examined. Colonic apoptosis and cell proliferation were evaluated. Wild type (wt) p53 was analyzed using reverse transcription–polymerase chain reaction (RT-PCR) and Western blotting. In addition, Bcl-2, Bcl-xL, Bax, and Bak localized in the mitochondria were detected. Long-term dietary corn oil increased ACF in AOM-treated rats at 12 weeks and promoted colon cancer invasion at 48 weeks. Cancer invasion was not observed in the AOM-treated rats without dietary corn oil, although colon adenomas and cancers were detected. Apoptosis was decreased and cell proliferation was increased in the AOM-treated rats with dietary corn oil, compared with the AOM-treated rats with dietary basal diet. In these rats, mitochondrial wt p53 was significantly inhibited through decreased mitochondrial localization of wt p53 and increased cytosolic p53, resulting in the upregulation of Bcl-2 and Bcl-xL and the downregulation of Bak in the mitochondria. Results suggest that long-term dietary corn oil promotes AOM-induced colon cancer development partly by inhibiting the tumor suppressor gene p53-mediated mitochondria-dependent apoptosis.
Functional Piglet Model for the Clinical Syndrome and Postmortem Findings Induced by Staphylococcal Enterotoxin B
Authors: Gessel Yvonne A. van , Mani Sachin , Bi Shuguang , Hammamieh Rasha , Shupp Jeffrey W. , Das Rina , Coleman Gary D. , Jett Marti
Published: July 2017

Staphylococcal enterotoxin (SE) B causes serious gastrointestinal illness, and intoxication with this exotoxin can lead to lethal toxic shock syndrome. In order to overcome significant shortcomings of current rodent and nonhuman primate models, we developed a piglet model of lethal SEB intoxication. Fourteen-day-old Yorkshire piglets were given intravenous SEB, observed clinically, and sacrificed at 4, 6, 24, 48, 72, or 96 hrs posttreatment. Clinical signs were biphasic with pyrexia, vomiting, and diarrhea within 4 hrs, followed by terminal hypotension and shock by 96 hrs. Mild lymphoid lesions were identified as early as 24 hrs, with severe lymphadenopathy, splenomegaly, and prominent Peyer's patches found by 72 hrs. Widespread edema—most prominent in the mesentery, between loops of spiral colon, and in retroperitoneal connective tissue—was found in animals at 72 hrs. Additional histologic changes included perivascular aggregates of large lymphocytes variably present in the lung and brain, circulating lymphoblasts, and lymphocytic portal hepatitis. Preliminary molecular investigation using gene array has uncovered several gene profile changes that may have implications in the pathophysiology leading to irreversible shock. Five genes were selected for further study, and all showed increased mRNA levels subsequent to SEB exposure. The use of this piglet model will continue to elucidate the pathogenesis of SEB intoxication and facilitate the testing of new therapeutic regimens that may better correlate with human lesions.
Impaired Hepatic Regeneration in Metallothionein-I/II Knockout Mice After Partial Hepatectomy
Authors: Oliver Jordan R. , Mara Tom W. , Cherian M. George
Published: July 2017

Although the translocation of metallothionein (MT) from cytoplasm to nucleus has been demonstrated in liver during times of high requirement for zinc (fetal development and the neonatal period), the role of MT in cellular growth is not well understood. In this study, a potential role of MT in liver regeneration was investigated in wild type (WT) and MT-I and MT-II gene knockout (MT-null) mice after 35% partial hepatectomy (PH) or sham laparotomy. Hepatic MT levels and proliferation index were measured at 0, 5, 15, 24, 36, 48, and 60 hrs after PH and 48 hrs after sham laparotomy (control). MT levels were increased in WT mice (peak at 24 hrs after PH) and declined to normal levels by 60 hrs after PH. Immunohistochemical staining for MT in WT mice indicated the presence of MT in both nucleus and cytoplasm of hepatocytes at 24 hrs after PH, whereas MT was present mainly in the cytoplasm at 36–60 hrs after PH and 48 hrs after sham laparotomy. Hepatic proliferation Index in both WT and MT-null mice, as determined by argyrophilic nucleolar organizing region staining and proliferating cell nuclear antigen immunohistochemical staining, reached a peak at 48 hrs and declined by 60 hrs after PH. Cell proliferation was significantly less in MT-null mice as compared to WT mice during liver regeneration after PH. These results suggest that MT may play a positive role in hepatic regeneration after PH.
Role of Metallothionein in Antigen-Related Airway Inflammation
Authors: Inoue Ken-Ichiro , Takano Hirohisa , Yanagisawa Rie , Sakurai Miho , Ichinose Takamichi , Sadakane Kaori , Hiyoshi Kyoko , Sato Masahiko , Shimada Akinori , Inoue Mamoru , Yoshikawa Toshikazu
Published: July 2017

Metallothionein (MT) is a protein that can be induced by inflammatory mediators and participates in cytoprotection. However, its role in antigen-related inflammation remains to be established. We determined whether intrinsic MT protects against antigen-related airway inflammation induced by ovalbumin (OVA) in MT-I/II null (MT [–/–]) mice and in corresponding wild-type (WT) mice. MT (–/–) mice and WT mice were intratracheally challenged with OVA (1 µg per body) biweekly four times. Twenty-four hours after the last OVA challenge, significant increases were shown in the numbers of total cells, eosinophils, and neutrophils in bronchoalveolar lavage fluid from MT (–/–) mice than in those from WT mice. The protein level of interleukin-1β (IL-1β) was significantly greater in MT (–/–) mice than in WT mice after OVA challenge. Immunohistochemical analysis showed that the formations of 8-oxy-deoxyguanosine and nitrotyrosine in the lung were more intense in MT (–/–) mice than in WT mice after OVA challenge. These results indicate that endogenous MT is a protective molecule against antigen-related airway inflammation induced by OVA, at least partly, via the suppression of enhanced lung expression of IL-1β and via the antioxidative properties. Our findings suggest that MT may be a therapeutic target for the treatment of antigen-related airway inflammatory diseases such as bronchial asthma.
Anti-Allergic Effects of Artemisia iwayomogi on Mast Cell-Mediated Allergy Model
Authors: Kim Sang-Hyun , Choi Cheol-Hee , Kim Sang-Yong , Eun Jae-Soon , Shin Tae-Yong
Published: July 2017

The discovery of drugs for the treatment of allergic disease is an important subject in human health. The Artemisia iwayomogi (Compositae) (AIE) has been used as a traditional medicine in Korea and is known to have an anti-inflammatory effect. However, its specific mechanism of action is still unknown. In this report, we investigated the effect of AIE on the mast cell-mediated allergy model and studied the possible mechanism of action. AIE inhibited compound 48/80–induced systemic reactions and plasma histamine release in mice. AIE decreased immunoglobulin E (lgE)–mediated local allergic reaction, passive cutaneous anaphylaxis (PCA) reaction. AIE dose dependency attenuated histamine release from rat peritoneal mast cells activated by compound 48/80 or IgE. AIE decreased the compound 48/80-induced intracellular Ca2+. Furthermore, AIE decreased the phorbol 12-myristate 13-acetate (PMA) plus calcium lonophore A23187-stimulated tumor necrosis factor-α and interleukin-6 gene expression and production in human mast cells. The inhibitory effect of AIE on the proinflammatory cytokine was p38 mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) dependent. AIE attenuated PMA plus A23187-lnduced degradation of licBa and nuclear translocation of NF-κB and specifically blocked activation of p38 MAPK but not that of c-jun N-terminal kinase and extracellular signal-regulated kinase. Our findings provide evidence that AIE inhibits mast cell-derived immediate-type allergic reactions and involvement of Intracellular Ca2+, proinflammatory cytokines, p38 MAPK, and NF-κB in these effects.
Immunologic and Biochemical Effects of the Fermented Wheat Germ Extract Avemar
Authors: Illmer Christoph , Madlener Sibylle , Horvath Zsuzsanna , Saiko Philipp , Losert Annemarie , Herbacek Irene , Grusch Michael , Krupitza Georg , Fritzer-Szekeres Monika , Szekeres Thomas
Published: July 2017

Avemar (MSC) is a nontoxic fermented wheat germ extract demonstrated to have antitumor effects. Avemar has the potential to significantly improve the survival rate in patients suffering from malignant colon tumors. We studied its effects in the HT-29 human colon carcinoma cell line. Avemar had an inhibiting effect on colonies of HT-29 cells with an IC50 value of 118 μg/ml (7 days of incubation); this value could be decreased to 100 and 75 μg/ml in the presence of vitamin C. In the cell line examined, Avemar induced both necrosis and apoptosis, as demonstrated by Hoechst/propldium iodide staining. The incubation of cells with 3200 μg/ml Avemar for 24 hrs caused necrosis in 28% and the induction of apoptosis in 22% of the cells. Avemar inhibited the cell-cycle progression of HT-29 cells in the G1 phase of the cell cycle. In addition, Avemar inhibited the activity of the key enzyme of de novo DNA synthesis, ribonucleotide reductase. In addition, we determined the effects of Avemar on the activity of cyclooxygenase-1 and -2. Both enzymes were significantly inhibited by Avemar with IC50 values of 100 and 300 μg/ml, respectively. We outline new explanations for its antitumor activity, which might serve as the basis for further studies using Avemar.
Endocannabinoids and Food Intake: Newborn Suckling and Appetite Regulation in Adulthood
Authors: Fride Ester , Bregman Tatyana , Kirkham Tim C.
Published: July 2017

The appetite-stimulating effects of the cannabis plant (Cannabis sativa) have been known since ancient times, and appear to be effected through the incentive and rewarding properties of foods. Investigations into the biological basis of the multiple effects of cannabis have yielded important breakthroughs in recent years: the discovery of two cannabinoid receptors in brain and peripheral organ systems, and endogenous ligands (endocannabinoids) for these receptors. These advances have greatly increased our understanding of how appetite is regulated through these endocannabinoid receptor systems. The presence of endocannabinoids in the developing brain and in maternal milk have led to evidence for a critical role for CB, receptors in oral motor control of suckling during neonatal development. The endocannabinoids appear to regulate energy balance and food intake at four functional levels within the brain and periphery: (i) limbic system (for hedonic evaluation of foods), (ii) hypothalamus and hindbrain (integrative functions), (iii) intestinal system, and (iv) adipose tissue. At each of these levels, the endocannabinoid system interacts with a number of better known molecules involved in appetite and weight regulation, including leptin, ghrelin, and the melanocortins. Therapeutically, appetite stimulation by cannabinoids has been studied for several decades, particularly in relation to cachexia and malnutrition associated with cancer, acquired immunodeficiency syndrome, or anorexia nervosa. The recent advances in cannabinoid pharmacology may lead to improved treatments for these conditions or, conversely, for combating excessive appetite and body weight, such as CB, receptor antagonists as antiobesity medications. In conclusion, the exciting progress in the understanding of how the endocannabinoid CB receptor systems influence appetite and body weight is stimulating the development of therapeutic orexigenic and anorectic agents. Furthermore, the role of cannabinoid CB, receptor activation for milk suckling in newborns may open new doors toward understanding nonorganic failure-to-thrive in infants, who display growth failure without known organic cause.
Differential Effects of cGMP Produced by Soluble and Particulate Guanylyl Cyclase on Mouse Ventricular Myocytes
Authors: Su Jun , Scholz Peter M. , Weiss Harvey R.
Published: July 2017

Particulate guanylyl cyclase (pGC) and soluble guanylyl cyclase (sGC) are cGMP-generation systems distributed in different intracellular locations. Our aim was to test the hypothesis that the functional effects of cGMP produced by pGC and sGC on contraction and Ca2+ transients would differ in ventricular myocytes. We measured myocyte shortening from adult mice using a video edge-detector and investigated the functional changes after stimulating pGC with C-type natriuretic peptide (CNP; 10–8 M and 10–7 M) or sGC with S-nitroso-N-acetyl-penicillamine (SNAP; nitric oxide donor; 10–6 M and 10–5 M). Significant concentration-dependent decreases in percentage shortening (PCS), maximal rate of shortening (RSmax), and relaxation (RRmax) were produced by CNP. To a similar degree, SNAP concentration-dependently reduced PCS, RSmax, and RRmax. The addition of Rp-8-[(4-chlorophenyl)thio]-cGMPS triethylamine (cGMP-dependent protein kinase inhibitor; 5 × 10–6 M) or erythro-9-(2-hydroxy-3-nonyl) adenine (cGMP-stimulated cAMP phosphodiesterase inhibitor; 10–5 M) reduced the responses induced by CNP or SNAP, suggesting that their actions were through cGMP-mediated pathways. While SNAP significantly increased intracellular cGMP concentration by 57%, CNP had little effect on cGMP production. We also found that CNP markedly decreased the amplitude of Ca2+ transients while SNAP had little effect, suggesting the cGMP generated by sGC may decrease myofilament Ca2+ sensitivity. The small amount of cGMP generated by pGC had a major effect in reducing Ca2+ level. This study suggested the existence of compartmentalization for cGMP in ventricular myocytes.
Endocrinologic Adaptations to Wintertime Fasting in the Male American Mink (Mustela vison)
Authors: Mustonen Anne-Mari , Saarela Seppo , PyykÖnen Teija , Nieminen Petteri
Published: July 2017

The aim of this study was to investigate the endocrine response to wintertime starvation in the male American mink (Mustela vison) fasted for 16 hrs, 2 days, 3 days, 5 days, or 7 days (n–10 per group). After 2 days of fasting, the plasma leptin concentrations decreased, along with the triiodothyronine, testosterone, and progesterone levels, and the blood monocyte counts. Leptin also seems to trigger the response to fasting in mustelids by inducing immunosuppression and downregulation of the reproductive and thyroid axes. The dramatic increase in the peptide YY concentrations after 3 days of fasting may be required to suppress gastrointestinal processes during food scarcity. The plasma insulin levels decreased, and those of glucagon increased after 5 days of fasting in association with efficient glucose sparing and lipid mobilization. Body energy stores cannot be wasted for growth during nutritional scarcity and, thus, the growth hormone levels of the minks decreased after 5 days of fasting. The plasma noradrenaline and cortisol concentrations also decreased after 3 and 7 days without food, respectively. The plasma ghrelin, adiponectin, resistin, thyroxine, adrenaline, or estradiol levels did not respond to fasting. The endocrine response to food deprivation is remarkably similar in divergent mammalian orders, indicating that the hormonal signals enhancing survival during nutritional scarcity must be evolutionarily old and well conserved.
Murine Macrophages Produce Endothelin-1 After Microbial Stimulation
Authors: Wahl Jeffrey R. , Goetsch Nicholas J. , Young Heather J. , Maanen Ryan J. Van , Johnson Jason D. , Pea Anisa S. , Brittingham Andrew
Published: July 2017

Endothelin-1 (ET-1) was originally characterized as a potent vasoconstrictor secreted by the endothelium and participating in the regulation of vascular tone. Subsequent analysis has revealed ET-1 to be a multifunctional peptide produced by a wide variety of cells and tissues under normal and pathologic conditions. The importance of macrophages as a source of ET-1 during infection and inflammation is supported by clinical observations in humans and in animal models of inflammation. We hypothesize that the production of ET-1 is part of the characteristic macrophage response to infection, and have begun to investigate the ability of various classes of microbes or microbial products to induce macrophage ET-1 production. We report the production of ET-1 by murine macrophages in response to stimulation with both gram-positive and gram-negative bacteria. Stimulation of macrophages with yeast (Candida albicans or Saccharomyces cerevisiae) or the protozoan parasite Leishmania major, elicited no significant release of ET. The production of ET-1 in response to lipopolysaccharide (LPS) was dose and time dependent, and required the expression of a functional toll-like receptor 4 (TLR4). Pharmacologic inhibition of the transcription factor, nuclear factor-κB (NF-κB) suppressed LPS-induced ET-1 production. Our findings complement the growing body of literature implicating a role for macrophage-derived ET-1 in inflammatory pathologies. The production of ET-1 by macrophages during infection and inflammation has the potential to affect tissue perfusion, leukocyte extravasation, and immune cell function.
Physiologic Interactions Between Macrophages and Leydig Cells
Authors: Hutson James C.
Published: July 2017

The purpose of this minireview is to present information concerning the morphologic and functional relationship between testicular macrophages and Leydig cells. Although data concerning the negative influence of macrophage-derived products on testicular Leydig cells exist, this review is focused on the stimulatory influences thought to be involved in the physiologic interactions between these two diverse cell types.
Accumulation of Symmetric Dimethylarginine in Hepatorenal Syndrome
Authors: Lluch Paloma , Mauricio Maria D. , Vila José M. , Segarra Gloria , Medina Pascual , Olmo Juan A. del , Rodrigo José M. , Serra Miguel A.
Published: July 2017

In patients with cirrhosis, nitric oxide (NO), asymmetric dimethylarginine (ADMA), and possibly symmetric dimethylarginine (SDMA) have been linked to the severity of the disease. We investigated whether plasma levels of dimethylarginines and NO are elevated in patients with hepatorenal syndrome (HRS), compared with patients with cirrhosis without renal failure (no-HRS). Plasma levels of NO, ADMA, SDMA, and l-arginine were measured in 11 patients with HRS, seven patients with no-HRS, and six healthy volunteers. SDMA concentration in HRS was higher than in no-HRS and healthy subjects (1.47 ± 0.25 vs. 0.38 ± 0.06 and 0.29 ± 0.04 μM, respectively; P < 0.05). ADMA and NOx concentrations were higher in HRS and no-HRS patients than in healthy subjects (ADMA, 1.20 ± 0.26, 1.11 ± 0.1, and 0.53 ± 0.06 μM, respectively; P < 0.05; NOx, 94 ± 9.1, 95.5 ± 9.54, and 37.67 ± 4.62 μM, respectively; P < 0.05). In patients with HRS there was a positive correlation between serum creatinine and plasma SDMA (r2 = 0.765, P < 0.001) but not between serum creatinine and ADMA or NOx. The results suggest that renal dysfunction is a main determinant of elevated SDMA concentration in HRS. Accumulation of ADMA as a result of impaired hepatic removal may be the causative factor initiating renal vasoconstriction and SDMA retention in the kidney.
Synergistic Effect of Hydrogen Peroxide and Elastase on Elastic Fiber Injury In Vitro
Authors: Cantor Jerome O. , Shteyngart Bronislava , Cerreta Joseph M. , Ma Shuren , Turino Gerard M.
Published: July 2017

This laboratory has previously shown that hyperoxia enhances airspace enlargement in a hamster model of elastase-induced emphysema. To further understand the mechanism responsible for this finding, the effect of oxidants on elastase activity was studied in vitro, using a radiolabeled elastic fiber matrix derived from rat pleural mesothelial cells. Matrix samples were treated with either 0.1%, 1%, 3%, or 10% hydrogen peroxide (H2O2) for 1 hr, then incubated with 1.0 μg/ml porcine pancreatic elastase for 2 hrs. Radioactivity released from the matrix was used as a measure of elastolysis. Results indicate that sequential exposure to H2O2 and elastase markedly enhanced elastolysis compared to enzyme treatment alone. A 22% increase in elastolysis was seen with 0.1% H2O2 (325 vs. 396 cpm; P < 0.05), whereas samples pretreated with 1%, 3%, and 10% H2O2 showed increases of 53% (274 vs. 420 cpm; P < 0.05), 71% (381 vs. 653 cpm; P < 0.01), and 38% (322 vs. 443 cpm; P < 0.01), respectively. Exposure to various concentrations of H2O2 alone (0.1% to 10%) produced only minimal elastolysis (<20 cpm). However, 1% H2O2 was capable of degrading peptide-free desmosine and isodesmosine, suggesting that exposure to this oxidant may reduce the stability of the elastic fiber matrix. With regard to lung diseases such as emphysema, H2O2 and other oxidants derived from inflammatory cells or the environment could possibly act as priming agents for elastase-mediated breakdown of elastic fibers, resulting in amplification of lung injury.
Fourier Transform Infrared Spectroscopic Analysis of the Intact Zona Pellucida of the Mammalian Egg: Changes in the Secondary Structure of Bovine Zona Pellucida Proteins During Fertilization
Authors: Nara Masayuki , Yonezawa Naoto , Shimada Takeshi , Takahashi Kazuya , Tanokura Masaru , Yumoto Fumiaki , Nakagawa Hiroyuki , Ohashi Kazuyo , Hamano Seizo , Nakano Minoru
Published: July 2017

The zona pellucida is the acellular transparent envelope surrounding the mammalian oocyte. An analysis of the changes in the structures of zona pellucida proteins is essential for understanding the molecular mechanisms underlying the important physiological roles of the zona during fertilization and prelmplantatlon. The hardening of the zona caused by the structural changes during fertilization is generally accepted to be responsible for blocking polyspermy. In this study, we analyzed changes in the secondary structure of the zona during fertilization by Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy. The predominance of β-sheet structure in porcine ovarian egg zona proteins in water was ascertained using FTIR spectra. α-Helix structure was also present. The attenuated total reflection (ATR)-FTIR spectrum of intact, unsolubilized porcine zonae pellucidae from ovarian eggs Indicated that the zona proteins in the native zona pellucida also have β-structure as the main constituent. Attenuated total reflectlon-FTIR spectroscopy of intact bovine zona pellucida obtained from ovarian and fertilized eggs at the blastocyst stage revealed that the β-structure content Increased during fertilization. Furthermore, a reduction of the thickness of the zona during fertilization was observed using transmission electron microscopy. Therefore, the change in the zona architecture that causes hardening of the zona during fertilization is accompanied by changes in the secondary structure of the zona proteins.
Hydrogen Peroxide as a Paracrine Vascular Mediator: Regulation and Signaling Leading to Dysfunction
Authors: Ardanaz Noelia , Pagano Patrick J.
Published: July 2017

Numerous studies have demonstrated the ability of a variety of vascular cells, including endothelial cells, smooth muscle cells, and fibroblasts, to produce reactive oxygen species (ROS). Until recently, major emphasis was placed on the production of superoxide anion (O2–) in the vasculature as a result of its ability to directly attenuate the biological activity of endothelium-derived nitric oxide (NO). The short half-life and radius of diffusion of O2–drastically limit the role of this ROS as an important paracrine hormone in vascular biology. On the contrary, in recent years, the O2–metabolite hydrogen peroxide (H2O2) has increasingly been viewed as an important cellular signaling agent in its own right, capable of modulating both contractile and growth-promoting pathways with more far-reaching effects. In this review, we will assess the vascular production of H2O2, its regulation by endogenous scavenger systems, and its ability to activate a variety of vascular signaling pathways, thereby leading to vascular contraction and growth. This discussion will include the ability of H2O2to (i) Initiate calcium flux as well as (ii) stimulate pathways leading to sensitization of contractile elements to calcium. The latter involves a variety of protein kinases that have also been strongly implicated in vascular hypertrophy. Previous Intensive study has emphasized the ability of NADPH oxidase-derived O2–and H2O2to activate these pathways in cultured smooth muscle cells. However, growing evidence indicates a considerably more complex array of unique oxidase systems in the endothelium, media, and adventitia that appear to participate in these deleterious effects in a sequential and temporal manner. Taken together, these findings seem consistent with a paracrine effect of H2O2across the vascular wall.
The Saponin-Mediated Enhanced Uptake of Targeted Saporin-Based Drugs is Strongly Dependent on the Saponin Structure
Authors: Bachran Christopher , Sutherland Mark , Heisler Iring , Hebestreit Philipp , Melzig Matthias F. , Fuchs Hendrik
Published: July 2017

Saponins are a group of plant glycosides consisting of a steroid or triterpenoid aglycone to which one or more sugar chains are attached. They exhibit cell membrane–permeabilizing properties and, thus, have been investigated for their therapeutic potential. Recently, at a nonpermeabilizing concentration saponinum album from Gypsophila paniculata L. has been described to enhance the cytotoxicity of a chimeric toxin in a cell culture model. To elucidate whether this enhancing effect is also mediated by other saponins, we analyzed the ability of seven different saponins to enhance the cytotoxicity of a targeted chimeric toxin. The chimeric toxin is composed of saporin, a plant ribosome-inactivating toxin, a cleavable adapter, and human epidermal growth factor (EGF). Cytotoxicity on EGF receptor (EGFR)-bearing cells was analyzed both alone and after combined application of saponin and chimeric toxin. Only two of the tested saponins, quillajasaponin and saponinum album, enhanced cytotoxicity by more than 1000-fold, whereas the enhancement factors of the other saponins were only approximately 10-fold. In contrast to saponinum album, quillajasaponin enhanced the cytotoxicity both on control cells lacking EGFR and on target cells, indicating that, in this case, the enhancement is not target cell receptor specific. This is also the case for some of the saponins with low enhancement factors. Saponinum album resulted in a more than 13,600-fold receptor-specific enhancement, decreasing the 50% inhibitory concentration (IC50) from 2.4 nM to 0.18 pM, which renders it the best option to promote saporin-3-based drug uptake while retaining specificity for the EGFR.