川井 薫

A decrease in the quality of sleep is believed to cause anxiety and worsen depression. Comparisons of salivary melatonin levels with different factors including quality of sleep, state and trait anxieties, and depression, were conducted to examine whether there is a relationship between melatonin, presumably associated with sleep, and psychological stress. The saliva of healthy young females was collected during the daytime and before they went to bed at night (when they were awake and resting in a sitting position), and salivary melatonin levels were measured. The quality of sleep was scored using the Pittsburgh Sleep Quality Index (PSQI)-a questionnaire method. State and trait anxieties, and depression were scored using other questionnaire methods: the State-Trait Anxiety Inventory (STAI) and Self-Rating Depression Scale (SDS), respectively. The following findings were obtained: (1) Salivary melatonin levels measured during the daytime and before going to bed were higher in females with a high depression score, compared to those with a low score, and there was a correlation between the depression scores and salivary melatonin levels measured at night; and (2) salivary melatonin levels measured before going to bed at night (in a sitting position) were higher in females with a high state anxiety score, suggesting a correlation between state anxiety scores and salivary melatonin levels during the night. Both depression and a sense of anxiety are forms of psychological stress. Therefore, it is assumed that, when a person is under psychological stress, the action of melatonin as a ligand on its receptor is reduced. Meaning psychological stress may induce oxidative stress in the body. On the other hand, no correlation was noted between the quality of sleep and salivary melatonin levels during the night, presumably because saliva was collected when the subjects were awake and sitting, rather than sleeping.

We established a highly reproducible, simple and rapid simultaneous measurement method in which blood plasma can be directly injected into high-performance liquid chromatography (HPLC) without conducting conventional extraction of kynurenine (Kyn) and tryptophan (Trp) from blood plasma. In this method, Kyn and Trp were first separated from proteins present in blood plasma using a pre-column. Then, by column-switching, the separated Kyn and Trp were automatically injected into a separation column. The recoveries of Kyn and Trp determined in blood plasma by this method were 100.0 ± 0.9 and 100.0 ± 1.4%, respectively. © 2007 Elsevier B.V. All rights reserved.

In order to investigate the effect of mental stress on the tryptophan metabolism, a stress model of visual display terminals work was loaded on healthy students. Before and just after stress, plasma samples were collected and serotonin, tryptophan and kynurenine were assayed. The plasma concentration of serotonin was increased by visual display terminals work. Both Trp and Kyn concentrations were decreased after stress load. These results suggest that serotonin formation from tryptophan may be accelerated, resulting in the suppressing of kynurenine metabolism from tryptophan. Furthermore, when these subjects were divided into two groups, one group of those accustomed to the personal computer and another group of those not accustomed, the changes of above amines and scores of Profile of Mood States in the latter group were larger than that in the former group. These results also suggest that the activation of the person with a strong psychological load is larger than that of a weak person. © 2007.

We have hypothesized that a close correlation exists between tryptophan metabolism, exercise performance and mood. Before and after a 20-km run, a POMS test and serum l-kynurenine determination were performed. Serum l-kynurenine concentration was negatively correlated with running distance. After running, scores for Vigor and serum l-kynurenine concentration were correlated (r = 0.556) subjects with higher l-kynurenine concentrations tended to have higher scores for Vigor. In this study, we attempted to confirm this hypothesis. The present results suggest a close correlation between tryptophan metabolism, exercise performance and mood. © 2007 Elsevier B.V. All rights reserved.

Monthly variations in the concentrations of barbaloin, isobarbaloin, aloenin, protein, saccharide, polyamines, and the carboxypeptidase activity of Aloe arborescens Miller var. natalensis Berger (Japanese name Kidachi aloe) were studied and correlated with temperature and rainfall. The overall concentration or activity of the components was high in the warm season and low in the cold season, and protein, saccharide, polyamines and carboxypeptidase were strongly affected by rainfall putrescine occurred in low concentrations in August (drought period) and during cultivation in a greenhouse (cold season without watering). The concentrations of barbaloin, isobarbaloin, aloenin, protein, saccharide and carboxypeptidase in different parts and positions of the leaf of Kidachi aloe were also studied. (C) 2004 Elsevier Ltd. All rights reserved.

Trichophytosis was induced in guinea-pigs and the antifungal effects of Aloe arborescens Miller var. natalensis Berger (Kidachi aloe) evaluated in comparison with lanoconazole, a commercially available antifungal agent. Trichophytosis was induced by inoculation of arthrospores of Trichophyton mentagrophytes cephalic strain SM-110 (T. mentagrophytes SM-110) onto the plantar part of guinea-pig feet. Culture studies after application of 30% freeze-dried Kidachi aloe for 10 days showed a 70% growth inhibition compared with the untreated animals. In an in vitro experiment, the fraction of Kidachi aloe with molecular weights less than 10000 and a bioactive compound of barbaloin, a low molecular weight component of Kidachi aloe, showed growth inhibition of Trichophyton at a minimum concentration of 75 mg/mL and 200 mu g/mL. (C) 1998 John Wiley & Sons, Ltd.

The circadian changes in the concentrations of monoamines and their metabolites in plasma [tyrosine (Tyr), 3-methoxydopa (3-OMD), dopamine (DA), norepinephrine (NE), epinephrine (EN), homovanilic acid (HVA), vanillylmandelic acid (VMA), 3-methoxy-4-hydroxyphenylglycol (MHPG), tryptophan (Trp), 5-hydroxyindoleacetic acid (5-HIAA)] obtained at (05:00 AM and 13:00 PM) and their total contents in W-hour urine from 15 healthy subjects were simultaneously determined using an HPLC/multi-electrode electrochemical detection. Their precursor amino acids, Tyr and Trp, and dopamine beta-hydroxylase (DBH) activity, which is mainly secreted from the peripheral catecholamine systems of the sympathetic nerves and adrenal medulla into the blood and shows circadian variations (minimum at 05:00 AM and maximum at 13:00 PM) were also determined. Many monoamine parameters, especially NE and EN, showed higher values in plasma at 13:00 PM, whereas the levels of HVA, VMA and 5-HIAA tended to be low at 13:00 PM. Significant correlations were observed between each monoamine.

We examined the modifying effect of hemicalcium ascorbate (Ca-Asc), and its lipophilic derivatives, 2-O-octadecylascorbic acid (CV-3611) and ascorbyl palmitate (AscP), on hepatocarcinogenesis by 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) in ODS rats (a mutant unable to synthesize ascorbic acid). Male 14-week-old ODS rats were given a modified AIN-A diet or the diet containing 0.06% 3'-Me-DAB, and drinking water containing 0.1% ascorbic acid. Rats were divided into the following eight groups: Group 1, no treatment (basal diet alone); Group 2, Ca-Asc; Group 3, CV-3611;Group 4, AscP; Group 5, 3'-Me-DAB; Group 6, 3'-Me-DAB + Ca-Asc; Group 7, 3'-Me-DAB + CV-3611; and Group 8, 3'-Me-DAB + AscP. Ca-Asc (2 g/kg), CV-3611 (0.2 g/kg), and AscP (0.6 g/kg) was administered once every day by gavage. 3'-Me-DAB was given in the basal diet. After 17 weeks, animals were killed by exsanguination, and the liver was weighed and processed for histological examination. Treatment by CV-3611 exerted a marked inhibitory effect on the development of 3'-Me-DAB-induced hepatocellular carcinomas (HCC) as measured by multiplicity. Although less effective than CV-3611, Ca-Asc and AscP also showed inhibitory effect. We have also studied the correlation of erythrocyte (RBC) polyamine levels and HCC development. RBC polyamine levels were inhibited by Ca-Asc and its derivatives, indicating it may be a marker of hepatocarcinogenesis.

Serum dopamine-beta-hydroxylase (DBH, dopamine beta-monooxygenase ; EC 1.14.17.1) is derived from peripheral sympathetic nerves together with norepinephrine. Serum DBH shows circadian variations. We have developed a simple method to estimate the circadian variation, and have applied the method for the study of serum DBH in schizophrenic patients. We estimated the times at which the activity of serum DBH showed the maximum and minimum levels from the circadian rhythm in 40 normal controls. We then compared the activities at these two points between schizophrenic patients and normal controls, and evaluated the significance of the circadian variation of serum DBH activity as a biochemical marker in schizophrenia. From the circadian rhythm of the serum DBH activity (IU, mu-mol/min per liter serum) in 40 normal controls, 5:00 a.m. (minimum activity) and 13:00 p.m. (maximum activity) were selected as the two measurement points to estimate circadian variation. The serum DBH activity was then measured at these times in 40 normal controls and 166 volunteer patients with schizophrenia during 5 consecutive days. The mean serum DBH activities at 5:00 and 13:00 were significantly lower in 166 schizophrenic patients than those in 40 normal controls (25.65 +/- 0.91 vs 42.79 +/- 3.59 at 5:00 ; 25.80 +/- 0.92 vs 44.50 +/- 3.67 at 13:00), conforming to our previous report [Fujita, K. et al, (1978) J. Newochem, 30, 1569 - 1572]. The difference between the mean DBH levels at 13:00 and 5:00 was divided by the mean activity of the values at all 10 time points during the 5 days, and this value was defined as the circadian variation in serum DBH activity (%). The circadian variation in serum DBH activity (mean @ SEM) was 4.37 +/- 0.48 (%) in 40 normal controls and 1.05 +/- 0.33 (%) in 166 schizophrenic patients, being significantly smaller in schizophrenic patients than in normal controls (p < 0.001). Furthermore, in 6 from 40 normal controls and 78 from 166 schizophrenic patients whose serum DBH levels were less than 25 IU, the mean circadian variation in serum DBH activity was 6.33 +/- 1.95 (%) in normal controls and 1.02 +/- 0.55 (%) in schizophrenic patients (P < 0.05). Similarly, in schizophrenic patients and normal controls whose serum DBH levels were 25 IU and above, the circadian variation in DBH was 4.03 +/- 0.45 (%) in normal controls and 1.09 +/- 0.39 (%) in schizophrenic patients (p < 0.001). Significantly lower circadian variations were observed in three types of schizophrenia ; hebephrenic, Paranoid and catatonic forms. These results indicate that the circadian variation in serum DBH is significantly decreased in schizophrenic patients regardless of the mean serum DBH activity during 24 hours and of the types of disease. Therefore, the variation in DBH is considered to be useful as a biochemical marker in schizophrenia.