Changes in the Intestinal Microbiota of Wild Atlantic cod Gadus morhua L. Upon Captive Rearing

The commensal microbiota plays an important role in the well-being of the host organism, and it would be worthwhile to know the tenacious communities among them. Therefore, a study was undertaken to examine the changes in constitution of the intestinal microbiota of wild fish consequential to captivity. At first, the composition of intestinal microorganisms of Atlantic cod caught from the coastal area off Bod?, Norway, was examined. Thereafter, the changes in the bacterial community of the captive fish after offering them artificial feed or subjecting them to starvation were studied. The microbiota from the intestinal contents and wall segments were analyzed quantitatively by spread plate technique and DAPI staining and qualitatively by denaturing gradient gel electrophoresis. The study revealed that the counts of intestinal microbes in wild-caught Atlantic cod were not affected by captive rearing for 6?weeks, either when fed or when starved. However, the diversity of intestinal bacterial community was reduced in response to artificial feeding, whereas the change was restricted upon starvation.     

Impact of lifestyle on circadian orientation and sleep behaviour

Sleep and Biological Rhythms - Individual variability in preferred sleep timing is popularly described as chronotype. This study was conducted on 2105 subjects living in remote (500; without...     

Three-dimensional interactions between enhancers and promoters during intestinal differentiation depend upon HNF4

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Somatic embryogenesis,regeneration and <Emphasis Type="Italic">in vitro</Emphasis> production of glycyrrhizic acid from root cultures of <Emphasis Type="Italic">Taverniera cuneifolia</Emphasis> (Roth) Arn.

Taverniera cuneifolia (Roth) Arn. or Indian licorice is considered to be a substitute for Glycyrrhiza glabra L. owing to an equivalent content of glycyrrhizic acid (GA). GA recognized as the main active ingredient of T. cuneifolia, GA imparts several medicinal properties to these plants. However, research on this plant is scanty with no published record on tissue culture studies. Present study demonstrates a method for (1) induction and successful development of somatic embryos from the root culture, (2) regeneration of plants, and (3) GA production by root cultures of T. cuneifolia. Shoot initiation frequency of cultured roots ranged from 52.57% to 97.71%. Plant regeneration frequency (germination) from somatic embryos was 88.66% in 1/4-strength Murashige and Skoog (MS) medium supplemented with 2% sucrose, as against 68% in half 1/2-strength MS containing 2% sucrose. Glycyrrhizic acid of 1.32 mg/gm of dry weight was obtained in full-strength MS medium supplemented with 3% sucrose, through high-performance thin layer chromatography analysis with standard GA in root cultures. The present study provides an efficient method for the mass production of plants from a single mother plant as well as the potential root culture system to study the GA production pathways in T. cuneifolia.     

Comparison of innate immune activation after prolonged feeding of milk fermented with three species of Lactobacilli

The present investigation aimed at identifying the abilities of three different species of probiotic lactobacilli to modulate cellular immune responses in mouse neutrophils and macrophages in vivo over a study period of 60 days. Neutrophil respiratory burst enzymes (cytochrome c reductase and MPO) showed remarkable increased activity (P ≤ 0.01) after consumption of milks fermented by different species of probiotics over 30 and 60 days of feeding trials. Enzyme activities (β‐galactosidase and β‐glucuronidase) and nitric oxide production also increased considerably (P ≤ 0.01) in macrophages, both in peritoneal fluid and in enriched cell cultures. The effects of enhanced enzyme activities were corroborated by simultaneous increases in the phagocytic activities of neutrophils and macrophages. The increases in cellular functions were invariably maximal during the first 30 days of study and were maintained, but did not increase, over the next 30 days. Further, Lactobacillus helveticus‐fed groups were most effective at modulating neutrophil functions whereas Lactobacillus paracasei‐fed groups were more potent at enhancing macrophage functions. Together, our results indicate that probiotics have strain specific effects on stimulating cellular functions while not causing excessive stimulation of the immune system over longer feeding periods, thereby resulting in maximum and stable health benefits.     

SUMOylation of Pancreatic Glucokinase Regulates Its Cellular Stability and Activity

Glucokinase is the predominant hexokinase expressed in hepatocytes and pancreatic β-cells, with a pivotal role in regulating glucose-stimulated insulin secretion, illustrated by glucokinase gene mutations causing monogenic diabetes and congenital hyperinsulinemic hypoglycemia. A complex tissue-specific network of mechanisms regulates this enzyme, and a major unanswered question in glucokinase biology is how post-translational modifications control the function of the enzyme. Here, we show that the pancreatic isoform of human glucokinase is SUMOylated in vitro, using recombinant enzymes, and in insulin-secreting model cells. Three N-terminal lysines unique for the pancreatic isoform (Lys-12/Lys-13 and/or Lys-15) may represent one SUMOylation site, with an additional site (Lys-346) common for the pancreatic and the liver isoform. SUMO-1 and E2 overexpression stabilized preferentially the wild-type human pancreatic enzyme in MIN6 β-cells, and SUMOylation increased the catalytic activity of recombinant human glucokinase in vitro and also of glucokinase in target cells. Small ubiquitin-like modifier conjugation represents a novel form of post-translational modification of the enzyme, and it may have an important regulatory function in pancreatic β-cells.