Sodium Glucose Co-Transporter 2 Inhibitors Ameliorate Endothelium Barrier Dysfunction Induced by Cyclic Stretch through Inhibition of Reactive Oxygen Species

SGLT-2i's exert direct anti-inflammatory and anti-oxidative effects on resting endothelial cells. However, endothelial cells are constantly exposed to mechanical forces such as cyclic stretch. Enhanced stretch increases the production of reactive oxygen species (ROS) and thereby impairs endothelial barrier function. We hypothesized that the SGLT-2i's empagliflozin (EMPA), dapagliflozin (DAPA) and canagliflozin (CANA) exert an anti-oxidative effect and alleviate cyclic stretch-induced endothelial permeability in human coronary artery endothelial cells (HCAECs). HCAECs were pre-incubated with one of the SGLT-2i's (1 µM EMPA, 1 µM DAPA and 3 µM CANA) for 2 h, followed by 10% stretch for 24 h. HCAECs exposed to 5% stretch were considered as control. Involvement of ROS was measured using N-acetyl-l-cysteine (NAC). The sodium-hydrogen exchanger 1 (NHE1) and NADPH oxidases (NOXs) were inhibited by cariporide, or GKT136901, respectively. Cell permeability and ROS were investigated by fluorescence intensity imaging. Cell permeability and ROS production were increased by 10% stretch; EMPA, DAPA and CANA decreased this effect significantly. Cariporide and GKT136901 inhibited stretch-induced ROS production but neither of them further reduced ROS production when combined with EMPA. SGLT-2i's improve the barrier dysfunction of HCAECs under enhanced stretch and this effect might be mediated through scavenging of ROS. Anti-oxidative effect of SGLT-2i's might be partially mediated by inhibition of NHE1 and NOXs.

Phosphorylation of Helicobacter pylori CagA by c-Abl leads to cell motility

Helicobacter pylori induces a strong motogenic response in infected gastric epithelial host cells, which is enhanced by translocation of the pathogenic factor cytotoxin-associated gene A (CagA) into host cells via a specialized type IV secretion system. Once injected into the cytosol CagA is rapidly tyrosine phosphorylated by Src family kinases followed by Src inactivation. Hence, it remained unknown why CagA is constantly phosphorylated in sustained H. pylori infections to induce cell migration, whereas other substrates of Src kinases are dephosphorylated. Here, we identify the non-receptor tyrosine kinase c-Abl as a crucial mediator of H. pylori-induced migration and novel CagA kinase in epithelial cells. Upon H. pylori infection c-Abl directly interacts with CagA and localizes in focal adhesion complexes and membrane ruffles, which are highly dynamic cytoskeletal structures necessary for cell motility. Selective inhibition of c-Abl kinase activity by STI571 or shRNA abrogates sustained CagA phosphorylation and epithelial cell migration, indicating a pivotal role of c-Abl in H. pylori infection and pathogenicity. These results implicate c-Abl as a novel molecular target for therapeutic intervention in H. pylori-related gastric diseases.

Beta 3-adrenergic-receptor allele distributions in children, adolescents and young adults with obesity, underweight or anorexia nervosa

OBJECTIVE

The missense mutation (64Trp to 64Arg) in the beta 3-adrenergic-receptor has previously been described to confer a genetic predisposition to the development of obesity.

DESIGN

To test the hypothesis we evaluated allele frequencies in children, adolescents and young adults who belonged to different weight groups that were delineated with percentiles for the body mass index (BMI; kg/m2).

SUBJECTS

99 underweight probands (BMI < or = 15th percentile). 80 normal weight probands (BMI: 5th-85th percentile). 238 obese children and adolescents (BMI > or = 97th percentile). 84 patients with anorexia nervosa (AN).

MEASUREMENTS

The cohorts were screened by polymerase chain reaction with subsequent restriction fragment length polymorphism (PCR-RFLP) analysis. Data were statistically analysed for association. In addition to these case control studies, the transmission disequilibrium test (TDT) was applied to 80 families of obese probands and to 52 families of patients with AN.

RESULTS

Both the tests for association and linkage were negative. The Trp64Arg allele frequencies in the three weight groups (obesity: 0.071; normal weight: 0.081; underweight: 0.056) and the AN patients (0.054) were similar. Extremely obese individuals showed no excess of the Trp64Arg allele. No homozygotes for the Trp64Arg allele were detected.

CONCLUSION

Heterozygosity for the Trp64Arg allele is not of major importance in regulation of body weight in individuals younger than 35 y. Additionally, the extreme obese subgroup is not enriched for the polymorphism.

Tactile recognition of laterally inverted mirror images by children: intermanual transfer and rotation of the palm

Intermanual tactile recognition of laterally inverted mirror shapes was studied, with special reference to the role of the thumb. Children were allowed to feel the shapes either with the whole hand, with only four fingers (excluding the thumb), or with only the index finger. Intramanual recognition was also studied after rotation of the hand from the palm down/up to the palm up/down orientation. The thumb was found not to be important for intermanual mirror reversals, and only of limited importance for intramanual reversals. There was no evidence that coding with reference to the hand is of importance for either inter or intramamual reversals. The explanations for the two kinds of reversals are quite different.

[Sensory and chemical changes of dried foods under the influence of extreme storage conditions. 1. Method of sensory evaluation (author's transl)]

This paper described a method for the evaluation of sensory changes in the quality of dried foods, which have been stored under extreme conditions. The applied method is based on the 5 point DLG-scale, the structure of this scale has been adapted to the requirements of a methematical-statistical evaluation. In addition standard samples are provided as reference during the test.

[Sensory and chemical changes of dried foods under the influence of extreme storage conditions. 2. Sensory changes (author's transl)]

The sensory quality of dried infant foods is decreasing steadily during the storage under extreme conditions. Odor and taste are influenced to a higher degree than colour and consistency. A package with a high permeability for oxygen and water vapor has an unfavourable effect on the storability. The composition of the investigated products has no influence on the sensory estimation, but a significant influence on the storage behavior.

[Sensory and chemical changes of dried foods under the influence of extreme storage conditions. 3. Chemical changes (authors transl)]

The content of free amino acids and free fatty acids of dried infant foods is clearly decreasing during the storage under extreme conditions, whilst the percentage composition of the fatty acids in the triglycerides remains nearly unchanged. The content of hydroxymethylfurfural is connected with the sensory changes. For the single foods as well a high increase as a strong decrease of the HMF-content can be combined with distinct sensory changes. The vitamin C-content decreases during the storage, the permeability of the packing material for oxygen and water vapor has an unfavourable effect. Furthermore the pH-value of the investigated products is lowered during the storage period.

[Sensory and chemical changes of dried foods under the influence of extreme storage conditions. 4. Flavor compounds (authors transl)]

From dried infant foods stored under extreme conditions aroma compounds have been isolated analyzed by gas chromatography and mass spectrometry. The results has been, that during the storage long chain aliphatic aldehydes are newly formed.--It is scarcely possible to attach the investigated chemical parameters (content of ascorbic acid, free amino acids and free fatty acids, hydroxymethylfurfural, pH-value) for the investigated products to a sensory impression.