Development of strains of the thermotolerant yeast Hansenula polymorpha capable of alcoholic fermentation of starch and xylan

The thermotolerant yeast Hansenula polymorpha ferments glucose and xylose to ethanol at high temperatures. However, H. polymorpha cannot utilize starchy materials or xylans. Heterologous amylolytic and xylanolytic enzymes have to be expressed in this yeast to provide for utilization and growth on starch and xylan. Genes SWA2 and GAM1 from the yeast Schwanniomyces occidentalis, encoding α-amylase and glucoamylase, respectively, were expressed in H. polymorpha. The expression was achieved by integration of the SWA2 and GAM1 genes under the strong constitutive promoter of the H. polymorpha glyceraldehyde-3-phosphate dehydrogenase gene (HpGAP) into H. polymorpha genome. Resulting transformants acquired the ability to grow on a minimal medium containing soluble starch as a sole carbon source. Ethanol production at high-temperature fermentation from starch by the recombinant strains was up to 10 g/L. The XYN2 gene encoding endoxylanase of the fungus Trichoderma reseei was expressed in H. polymorpha. Co-expression of xlnD gene coding for β-xylosidase of the fungus Aspergillus niger and the XYN2 gene in H. polymorpha was achieved by integration of these genes under control of the HpGAP promoter. Resulting transformants were capable of growth and alcoholic fermentation on a minimal medium supplemented with birchwood xylan as a sole carbon source at 48 °C.     

Daily profiles of plasma prolactin (PRL), growth hormone (GH), insulin-like growth factor-1 (IGF-1), luteinizing hormone (LH), testosterone, and melatonin, and of pituitary PRL mRNA and GH mRNA in male Long Evans rats in acute phase of adjuvant arthritis

We studied the effects of adjuvant arthritis (AA) on the endocrine circadian rhythms of plasma prolactin (PRL), growth hormone (GH), insulin-like growth factor-1 (IGF-1), luteinizing hormone (LH), testosterone, and melatonin and of pituitary PRL and GH mRNA in male Long Evans rats. Groups of control and AA rats (studied 23 days after AA induction) that were housed under a 12/12 h light/dark cycle (light on at 06:00 h) were killed at 4 h intervals starting at 14:00 h. Cosinor analysis revealed a significant 12 h rhythm in PRL and PRL mRNA (p < 0.001) in controls with peaks at 14:00 h and 02:00 h, respectively. The peak at 02:00 h was abolished in the AA group resulting in a significant 24 h rhythm in parallel with that of PRL (p < 0.05) and PRL mRNA (p < 0.0001). Growth hormone showed no rhythm, but a significant rhythm of GH mRNA was present in both groups (p < 0.0001). Insulin-like growth factor-1 showed a 24 h rhythm in control but not in AA rats. The mean values of GH, GH mRNA, and IGF-1 were significantly reduced in AA. Luteinizing hormone displayed a significant 24 h rhythm (p < 0.01) peaking in the dark period in the control but not AA group. Testosterone showed in phase temporal changes of LH levels with AA abolishing the 02:00 h peak. Melatonin exhibited a significant 24 h rhythm in control (p < 0.001) and AA (p < 0.01) rats with maximum levels during the dark phase; the mesor value was higher in the AA males. These results demonstrate that AA interferes with the rhythms of all the studied hormones except the non-24 h (arrhythmic) GH secretion pattern and the rhythm in melatonin. The persistence of a distinct melatonin rhythm in AA suggests the observed disturbances of hormonal rhythms in this condition do not occur at the level of the pineal gland.     

Differential expression of glucose transporters in rabbit placenta: effect of hypercholesterolemia in dams

Low birth weight is observed in rabbit offspring when maternal hypercholesterolemia is induced during gestation, but the related etiology is still unknown. Glucose is one of the most important substances during fetal development, and defect in glucose supply to fetus was related to pathophysiological mechanisms in intrauterine growth restriction. Thus, the aim of this work was to evaluate the impact of maternal hypercholesterolemia during rabbit gestation on the glucose metabolism and the routing of glucose transporters (SLC2 and SLC5 [previously known as GLUT and SGLT]) in placenta. In this study, maternal and offspring serum levels of glucose and insulin were evaluated for control and hypercholesterolemic groups, and the mRNA and protein expressions of placental SLCs were quantified by real-time RT-PCR and Western immunoblot, respectively. Our data demonstrate that maternal hypercholesterolemia during gestation: 1) induces offspring hypoglycemia; 2) does not modify the genetic and protein expressions of SLC2A1 and SLC2A4 (previously GLUT1 and GLUT4) in total placental extract; 3) downregulates the placental SLC5A1 (previously SGLT1) protein expression without affecting its mRNA levels; 4) impairs the translocation of SLC2A1 but not SLC2A4 from cytoplasmatic pool to the cell membrane surface. Then we assume that reduction of offspring birth weight in presence of maternal hypercholesterolemia may be related to the offspring's hypoglycemia and the reduction of the cell surface expression of placental SLC2A1.     

Activation of aerobic metabolism by Amaranth oil improves heart rate variability both in athletes and patients with type 2 diabetes mellitus

The aim of present research was to study the effects of Amaranth oil (AmO) supplementation on aerobic metabolism and heart rate variability (HRV) in type 2 diabetes mellitus patients and in athletes. Several parameters of aerobic metabolism and HRV were assessed. Supplementation with AmO caused mild pro-oxidant activity resulting in improved uptake of oxidative destruction products and modulation of catalase and SOD activity with subsequent development of an antioxidant effect. These findings were very distinct in athletes but less pronounced in diabetics. Redistribution of haemoglobin ligands in athletes indicates involvement of haemoproteins in free radical reactions during AmO supplementation. Improvement in HRV by daily consumption of AmO as observed in both study groups suggested increased production of endogenous oxygen and enhancement of the cardio-respiratory function. The advantage of activation of aerobic metabolism in OS-related disorders resulting in improved self-organization of the living system and hormetic reaction mechanisms are discussed.     

Phytochemical Analysis and Antioxidant Activity of <i>Crocus speciosus</i> Leaves

The numerous studies indicate leaves of plants are a rich source of bioactive compounds that can be a valuable source of compounds used in the pharmaceutical and cosmetic industries. Aim of this study was to investigate the chemical composition and the antioxidant property of Crocus speciosus leaves. Primary phytochemical screening of C. speciosus leaves revealed the presence of some following compound categories such as phenolic compounds, aminoacids, saponins, proteins, tannins, triterpenoids, glycosides, polysaccharides. The total flavonoids and phenolic compounds content were determined spectrophotometrically and by HPLC-DAD and HPLC-MS. Antiradical activity was determined by ABTS radical-cation scavenging method, spectrophotometrically. The total amount of flavonoids in C. speciosus leaves was 1.07 ± 0.02 mg RE/g (p < 0.05), the total amount of phenolic compounds was 0.41 ± 0.01 mg GAE/g (p < 0.05). By HPLC-DAD-MS analysis the presence of the mangiferin, chlorogenic acid, isoorientin, kaempferol, hyperoside, and isoquercitin was established for the first time in Crocus leaves. The antiradical activity of C. speciosus leaves extracts was 150.08 ± 4.5 μmol/g (p < 0.05) and its was mainly attributed to phenolic compounds content. The high amounts of flavonoids and antiradical activity in C. speciosus leaves suggests promising phytochemical and pharmacological study of this Crocus species.