Neurite Outgrowth-Promoting Compounds from Cockscomb Hydrolysate

Cockscomb hydrolysate was found to have neurite outgrowth-promoting activity in PC12 cells. To investigate the neurite outgrowth-promoting compounds derived from cockscomb hydrolysate, bioassay-guided purification was carried out. Purified active fractions were obtained by liquid–liquid partition, followed by column chromatography. High-performance liquid chromatography and proton nuclear magnetic resonance analyses of the purified active fractions clarified that the main compounds are threonine, alanine, valine, and methionine. By screening for 20 kinds of amino acids, it was shown that valine and methionine, but not threonine and alanine, have neurite outgrowth-promoting activity. The results of activity evaluation of the mixture of amino acids indicated that alanine enhanced the activity of valine and that the mixture of valine and methionine showed a higher ratio of neurite formation than did each of them alone. On the other hand, dipeptides formed by valine and methionine showed weak neurite outgrowth-promoting activity. A mixture of threonine, alanine, valine, and methionine at the same concentrations as those in cockscomb hydrolysate showed neurite outgrowth-promoting activity comparable to that of cockscomb hydrolysate although threonine, alanine, valine, and methionine alone did not show activity at their concentrations in cockscomb hydrolysate. Therefore, the strong neurite outgrowth-promoting activity of cockscomb hydrolysate was considered to be due to the synergistic effect of threonine, alanine, valine, and methionine

Neurite Outgrowth-Promoting Activity of Compounds in PC12 Cells from Sunflower Seeds

In the current super-aging society, the establishment of methods for prevention and treatment of Alzheimer’s disease (AD) is an urgent task. One of the causes of AD is thought to be a decrease in the revel of nerve growth factor (NGF) in the brain. Compounds showing NGF-mimicking activity and NGF-enhancing activity have been examined as possible agents for improving symptoms. In the present study, sunflower seed extract was found to have neurite outgrowth-promoting activity, which is an NGF-enhancing activity, in PC12 cells. To investigate neurite outgrowth-promoting compounds from sunflower seed extract, bioassay-guided purification was carried out. The purified active fraction was obtained by liquid-liquid partition followed by some column chromatographies. Proton nuclear magnetic resonance and gas chromatography-mass spectrometry analyses of the purified active fraction indicated that the fraction was a mixture of β-sitosterol, stigmasterol and campesterol, with β-sitosterol being the main component. Neurite outgrowth-promoting activities of β-sitosterol, stigmasterol, campesterol and cholesterol were evaluated in PC12 cells. β-Sitosterol and stigmasterol showed the strongest activity of the four sterol compounds (β-sitosterol ≈ stigmasterol > campesterol > cholesterol), and cholesterol did not show any activity. The results indicated that β-sitosterol was the major component responsible for the neurite outgrowth-promoting activity of sunflower seeds. Results of immunostaining also showed that promotion by β-sitosterol of neurite formation induced by NGF was accompanied by neurofilament expression. β-Sitosterol, which showed NGF-enhancing activity, might be a candidate ingredient in food for prevention of AD

Loss of SOCS3 in T helper cells resulted in reduced immune responses and hyperproduction of interleukin 10 and transforming growth factor–β1

Suppressor of cytokine signaling (SOCS)3 is a major negative feedback regulator of signal transducer and activator of transcription (STAT)3-activating cytokines. Transgenic mouse studies indicate that high levels of SOCS3 in T cells result in type 2 T helper cell (Th2) skewing and lead to hypersensitivity to allergic diseases. To define the physiological roles of SOCS3 in T cells, we generated T cell–specific SOCS3 conditional knockout mice. We found that the mice lacking SOCS3 in T cells showed reduced immune responses not only to ovalbumin-induced airway hyperresponsiveness but also to Leishmania major infection. In vitro, SOCS3-deficient CD4+ T cells produced more transforming growth factor (TGF)-β1 and interleukin (IL)-10, but less IL-4 than control T cells, suggesting preferential Th3-like differentiation. We found that STAT3 positively regulates TGF-β1 promoter activity depending on the potential STAT3 binding sites. Furthermore, chromatin immunoprecipitation assay revealed that more STAT3 was recruited to the TGF-β1 promoter in SOCS3-deficient T cells than in control T cells. The activated STAT3 enhanced TGF-β1 and IL-10 expression in T cells, whereas the dominant-negative form of STAT3 suppressed these. From these findings, we propose that SOCS3 regulates the production of the immunoregulatory cytokines TGF-β1 and IL-10 through modulating STAT3 activation

Neurite Outgrowth-Promoting Activity of Compounds in PC12 Cells from Sunflower Seeds

In the current super-aging society, the establishment of methods for prevention and treatment of Alzheimer’s disease (AD) is an urgent task. One of the causes of AD is thought to be a decrease in the revel of nerve growth factor (NGF) in the brain. Compounds showing NGF-mimicking activity and NGF-enhancing activity have been examined as possible agents for improving symptoms. In the present study, sunflower seed extract was found to have neurite outgrowth-promoting activity, which is an NGF-enhancing activity, in PC12 cells. To investigate neurite outgrowth-promoting compounds from sunflower seed extract, bioassay-guided purification was carried out. The purified active fraction was obtained by liquid-liquid partition followed by some column chromatographies. Proton nuclear magnetic resonance and gas chromatography-mass spectrometry analyses of the purified active fraction indicated that the fraction was a mixture of β-sitosterol, stigmasterol and campesterol, with β-sitosterol being the main component. Neurite outgrowth-promoting activities of β-sitosterol, stigmasterol, campesterol and cholesterol were evaluated in PC12 cells. β-Sitosterol and stigmasterol showed the strongest activity of the four sterol compounds (β-sitosterol ≈ stigmasterol > campesterol > cholesterol), and cholesterol did not show any activity. The results indicated that β-sitosterol was the major component responsible for the neurite outgrowth-promoting activity of sunflower seeds. Results of immunostaining also showed that promotion by β-sitosterol of neurite formation induced by NGF was accompanied by neurofilament expression. β-Sitosterol, which showed NGF-enhancing activity, might be a candidate ingredient in food for prevention of AD

Neurite Outgrowth-Promoting Compounds from the Petals of Paeonia lactiflora in PC12 Cells

Isorhamnetin-3-O-glucoside and astragalin, flavonol glucosides, were isolated from the petals of Paeonia lactiflora as neurite outgrowth-promoting compounds. Isoquercitrin, formed by demethylating the B ring of isorhamnetin-3-O-glucoside or by adding a hydroxyl group to the B ring of astragalin, was evaluated for neurite outgrowth-promoting activity and was compared with the activities of isorhamnetin-3-O-glucoside and astragalin. The activities of isorhamnetin, kaempferol, and quercetin, aglycones corresponding to isorhamnetin-3-O-glucoside, astragalin, and isoquercitrin, respectively, were also evaluated. Isorhamnetin-3-O-glucoside and astragalin showed much stronger neurite outgrowth-promoting activities than the activities of the other tested flavonoids. They exhibited relatively weak anti-oxidant activities and moderate AChE inhibitory activities compared to the activities of the other tested flavonoids. Isorhamnetin-3-O-glucoside and astragalin promoted morphological neurite outgrowth and the expression of neurofilaments induced by NGF in PC12 cells. Isorhamnetin-3-O-glucoside and astragalin might be candidate compounds as neural differentiation agents in peripheral nerves and functional food ingredients preventing cognitive decline

Commissioning of the hypertriton binding energy measurement at MAMI

A high-precision hypernuclear experiment has been commissioned at the Mainz Microtron (MAMI) to determine the hypertriton Λ binding energy via decay-pion spectroscopy. The method has been successfully pioneered with 4ΛH studies in the last decade. The experiment makes use of a novel high luminosity lithium target with a length of 45mm while being only 0.75mm thick to keep momentum smearing of the decay pions low. The target-to-beam alignment as well as the observation of the deposited heat is achieved with a newly developed thermal imaging system. Together with a precise beam energy determination via the undulator light interference method a recalibration of the magnetic spectrometers will be done to obtain a statistical and systematic error of about 20 keV. The experiment started in the summer of 2022 and initial optimization studies for luminosity and data quality are presented