Effects of egg yolk choline intake on cognitive functions and plasma choline levels in healthy middle-aged and older Japanese: a randomized double-blinded placebo-controlled parallel-group study.

BACKGROUND: Choline, as a neurotransmitter acetylcholine precursor, is reportedly associated with cognitive function. Although there are several cohort and animal studies on choline-containing foods and cognitive function, only a few interventional studies were reported. Egg yolk is a rich source of different choline-containing chemical forms, such as phosphatidylcholine (PC), lysophosphatidylcholine (LPC), and α-glycerophosphocholine (α-GPC). This study aimed to investigate the effect of consuming 300 mg of egg yolk choline per day on cognitive function of Japanese adults. METHODS: A 12-week, randomized, double-blind, placebo-controlled, parallel-group study was conducted in 41 middle-aged and elderly males and females (43.9% female) aged ≥ 60 years and ≤ 80 years without dementia. Participants were randomly assigned to placebo and choline groups. The choline group received a supplement containing egg yolk choline (300 mg/day), and the placebo group received an egg yolk supplement free from choline for 12 weeks. Assessments of Cognitrax, Trail Making Tests (TMT) part A and B, the MOS 36-Item Short-Form Health Survey (SF-36), the Simplified Japanese Version of the WHO-Five Well-Being Index (WHO-5), and plasma choline levels were performed before and 6 and 12 weeks after supplement intake. In the present study, 19 subjects (9 in the placebo group and 10 in the choline group) were excluded due to the violation of the discontinuation criteria or participant compliance, and 41 subjects were analyzed. RESULTS: The change amount of verbal memory scores and verbal memory test-correct hit (delay) was significantly higher in the choline group than in the placebo group at baseline-6 and baseline-12 weeks. The plasma free choline level was significantly higher in the choline group compared with the placebo group at 6 weeks. Conversely, the choline group showed significantly lower Cognitrax processing speed scores, symbol digit coding testing correct responses, and SF-36 physical quality of life summary scores compared to the placebo group at 6 weeks. CONCLUSIONS: The results suggested that continued 300 mg/day intake of egg yolk choline improved verbal memory, which is a part of cognitive functions. To confirm the observed effects of egg yolk choline, more well-designed and large-scale studies are warranted. TRIAL REGISTRATION: Study protocols were pre-registered in the Clinical Trials Registration System (UMIN-CTR) (UMIN 000045050).

Repeated fruiting of Japanese golden chanterelle in pot culture with host seedlings.

Yellow chanterelles are among the most popular wild edible ectomycorrhizal mushrooms worldwide. The representative European golden chanterelle, Cantharellus cibarius, has only once been reported to fruit under greenhouse conditions, due to the difficulty of establishing pure culture. Recently, we developed a new technique for establishing a pure culture of a Japanese golden chanterelle (Cantharellus anzutake), and conducted in vitro ectomycorrhizal synthesis using established strains and Pinus densiflora. Acclimated pine mycorrhizal seedlings colonized with C. anzutake in a pot system under laboratory conditions produced small but distinct basidiomata with developed basidiospores. C. anzutake mycorrhizae were established on Quercus serrata seedlings by inoculation of mycorrhizal root tips of the fungus synthesized on P. densiflora. A scaled-up C. anzutake-host system in larger pots (4 L soil volume) exhibited repeated fruiting at 20-24 °C under continuous light illumination at 150 µmol m-2 s-1 during a 2-year incubation period. Therefore, a C. anzutake cultivation trial is practical under controlled environmental conditions.

Oral sodium hyaluronate relieves knee discomfort: A 12­week double­blinded, placebo­controlled study.

Sodium hyaluronate (SH) is a high molecular-weight polysaccharide composed of repeating polymeric disaccharides of D-glucuronic acid and N-acetyl-D-glucosamine. SH is present in every connective tissue and organ, with synovial fluid having the highest concentration of SH in the body. The effectiveness of oral SH on gonarthrosis is known; although, its influence on the knees of healthy individuals is not. However, as severe diseases may require surgery, it is better to take care of healthy knees before the onset of gonarthrosis. Therefore, the present study investigated the functionality of SH on the knee of healthy individuals. The present study was a randomized double-blind, placebo-controlled trial in which healthy adults (mean age: Placebo group, 61.50±1.59; SH group, 58.50±1.81), rated as grade ≤1 based on the Kellgren-Lawrence classification, were administered 111 mg/day SH for 12 weeks. The evaluation of visual analog scales were performed to assess the discomfort in the knees of the participants and were conducted at baseline, and then 6 and 12 weeks after the start of SH ingestion. Additionally, a locomotive syndrome risk test quantifying the mobility of the participants, a one-leg standing time with eyes open test evaluating the strength of the leg muscle as well as the ability to balance by measuring the time to stand on one leg and a blood test (interleukin-10, aspartate aminotransferase, alanine transaminase, γ-glutamyl transferase, lactate dehydrogenase, creatine kinase and C-reactive protein) were performed at baseline and then 12 weeks after the start of SH ingestion. A significant suppression of knee symptoms were demonstrated in the SH group compared with the placebo group in terms of the total visual analog scale scores for pain, stiffness and discomfort for the 31 healthy adult subjects. Significant suppression of symptoms was also demonstrated in the placebo group in terms of discomfort in the knees when descending stairs and pain in the knees after walking for a longer distance or duration than normal. No significant differences between the two groups were demonstrated in the locomotive syndrome risk test, one-leg standing time with eyes open test and the blood test. The results of the present study suggest the possibility that oral SH may help to maintain a healthy condition of the knees. The study protocol was registered with the University Hospital Medical Information Network Clinical Trial Registry in advance (registration no. UMIN000045980, November 4, 2021).

c-Src but not Fyn promotes proper spindle orientation in early prometaphase.

Src family tyrosine kinases (SFKs) participate in mitotic signal transduction events, including mitotic entry, cleavage furrow ingression, and cytokinesis abscission. Although SFKs have been shown to associate with the mitotic spindle, the role of SFKs in mitotic spindle formation remains unclear. Here, we show that c-Src promotes proper spindle orientation in early prometaphase. Src localizes close to spindle poles in a manner independent of Src kinase activity. Three-dimensional analyses showed that Src inhibition induced spindle misorientation, exhibiting a tilting spindle in early prometaphase. Spindle misorientation is frequently seen in SYF cells, which harbor triple knock-out mutations of c-Src, c-Yes, and Fyn, and reintroduction of c-Src but not Fyn into SYF cells rescued spindle misorientation. Spindle misorientation was also observed upon Src inhibition under conditions in which Aurora B was inhibited. Inducible expression of c-Src promoted a properly oriented bipolar spindle, which was suppressed by Src inhibition. Aster formation was severely inhibited in SYF cells upon Aurora B inhibition, which was rescued by reintroduction of c-Src into SYF cells. Furthermore, reintroduction of c-Src facilitated microtubule regrowth from cold-induced depolymerization and accelerated M phase progression. These results suggest that c-Src is involved in spindle orientation through centrosome-mediated aster formation.

Src-mediated tyrosine phosphorylation of PRC1 and kinastrin/SKAP on the mitotic spindle.

Src-family tyrosine kinases (SFKs) play important roles in a number of signal transduction events during mitosis, such as spindle formation. A relationship has been reported between SFKs and the mitotic spindle; however, the underlying mechanisms remain unclear. We herein demonstrated that SFKs accumulated in the centrosome region at the onset of mitosis. Centrosomal Fyn increased in the G2 phase in a microtubule polymerization-dependent manner. A mass spectrometry analysis using mitotic spindle preparations was performed to identify tyrosine-phosphorylated substrates. Protein regulator of cytokinesis 1 (PRC1) and kinastrin/small kinetochore-associated protein (kinastrin/SKAP) were identified as SFK substrates. SFKs mainly phosphorylated PRC1 at Tyr-464 and kinastrin at Tyr-87. Although wild-type PRC1 is associated with microtubules, phosphomimetic PRC1 impaired the ability to bind microtubules. Phosphomimetic kinastrin at Tyr-87 also impaired binding with microtubules. Collectively, these results suggest that tyrosine phosphorylation of PRC1 and kinastrin plays a role in their delocalization from microtubules during mitosis.