BACKGROUND Akt plays diverse roles in humans.It is involved in the pathogenesis of type 2 diabetes mellitus(T2DM),which is caused by insulin resistance.Akt also plays a vital role in human platelet activation.Furtherm...BACKGROUND Akt plays diverse roles in humans.It is involved in the pathogenesis of type 2 diabetes mellitus(T2DM),which is caused by insulin resistance.Akt also plays a vital role in human platelet activation.Furthermore,the hippocampus is closely associated with memory and learning,and a decrease in hippocampal volume is reportedly associated with an insulin-resistant phenotype in T2DM patients without dementia.AIM To investigate the relationship between Akt phosphorylation in unstimulated platelets and the hippocampal volume in T2DM patients.METHODS Platelet-rich plasma(PRP)was prepared from the venous blood of patients with T2DM or age-matched controls.The pellet lysate of the centrifuged PRP was subjected to western blotting to analyse the phosphorylation of Akt,p38 mitogen-activated protein(MAP)kinase and glyceraldehyde 3-phosphate dehydrogenase(GAPDH).Phosphorylation levels were quantified by densitometric analysis.Hippocampal volume was analysed using a voxel-based specific regional analysis system for Alzheimer’s disease on magnetic resonance imaging,which proposes the Z-score as a parameter that reflects hippocampal volume.RESULTS The levels of phosphorylated Akt corrected with phosphorylated p38 MAP kinase were inversely correlated with the Z-scores in the T2DM subjects,whereas the levels of phosphorylated Akt corrected with GAPDH were not.However,this relationship was not observed in the control patients.CONCLUSION These results suggest that an inverse relationship may exist between platelet Akt activation and hippocampal atrophy in T2DM patients.Our findings provide insight into the molecular mechanisms underlying T2DM hippocampal atrophy.展开更多
In order to examine the hydronium ion （proton）-releasing functions in cells, [pH]out （extracellular pH） was measured using an ion image sensor composed of a 2D （two-dimensional） array of potential sensitive pixe...In order to examine the hydronium ion （proton）-releasing functions in cells, [pH]out （extracellular pH） was measured using an ion image sensor composed of a 2D （two-dimensional） array of potential sensitive pixels. Using gastric tissues prepared from the stomach, pH distribution was observed during the histamine stimulation. The 2D distribution of [pH]out in the gastric tissues showed clear differences between the mucosal sides and the serous side. Even before the histamine stimulation, the mucosal side of the gastric mucosa showed a slightly lower pH than that of serous side. In the mucosal side, [pH]out decreased after the onset of the stimulation. The ion image sensor was capable of visualizing [pH]out in the gastric tissues. The present chemical-sensing technique realized a label-free microscopic assessment of the 2D distributions of biologically interesting substances, and consequently, [pH] out imaging via chemical microscopy has a future potential in medical fields for endoscopic analysis of gastric ulcers.展开更多
基金Research Funding for Longevity Science from The National Center for Geriatrics and Gerontology,Japan,No.19-21and No.22-19.
文摘BACKGROUND Akt plays diverse roles in humans.It is involved in the pathogenesis of type 2 diabetes mellitus(T2DM),which is caused by insulin resistance.Akt also plays a vital role in human platelet activation.Furthermore,the hippocampus is closely associated with memory and learning,and a decrease in hippocampal volume is reportedly associated with an insulin-resistant phenotype in T2DM patients without dementia.AIM To investigate the relationship between Akt phosphorylation in unstimulated platelets and the hippocampal volume in T2DM patients.METHODS Platelet-rich plasma(PRP)was prepared from the venous blood of patients with T2DM or age-matched controls.The pellet lysate of the centrifuged PRP was subjected to western blotting to analyse the phosphorylation of Akt,p38 mitogen-activated protein(MAP)kinase and glyceraldehyde 3-phosphate dehydrogenase(GAPDH).Phosphorylation levels were quantified by densitometric analysis.Hippocampal volume was analysed using a voxel-based specific regional analysis system for Alzheimer’s disease on magnetic resonance imaging,which proposes the Z-score as a parameter that reflects hippocampal volume.RESULTS The levels of phosphorylated Akt corrected with phosphorylated p38 MAP kinase were inversely correlated with the Z-scores in the T2DM subjects,whereas the levels of phosphorylated Akt corrected with GAPDH were not.However,this relationship was not observed in the control patients.CONCLUSION These results suggest that an inverse relationship may exist between platelet Akt activation and hippocampal atrophy in T2DM patients.Our findings provide insight into the molecular mechanisms underlying T2DM hippocampal atrophy.
文摘In order to examine the hydronium ion （proton）-releasing functions in cells, [pH]out （extracellular pH） was measured using an ion image sensor composed of a 2D （two-dimensional） array of potential sensitive pixels. Using gastric tissues prepared from the stomach, pH distribution was observed during the histamine stimulation. The 2D distribution of [pH]out in the gastric tissues showed clear differences between the mucosal sides and the serous side. Even before the histamine stimulation, the mucosal side of the gastric mucosa showed a slightly lower pH than that of serous side. In the mucosal side, [pH]out decreased after the onset of the stimulation. The ion image sensor was capable of visualizing [pH]out in the gastric tissues. The present chemical-sensing technique realized a label-free microscopic assessment of the 2D distributions of biologically interesting substances, and consequently, [pH] out imaging via chemical microscopy has a future potential in medical fields for endoscopic analysis of gastric ulcers.
