[The stress symptoms and posttraumatic growth of dispatched firefighters following the Great East Japan Earthquake].

This study investigated posttraumatic stress symptoms and posttraumatic growth among 534 fire fighters who were dispatched to the disaster area following the Great East Japan Earthquake. Specifically, we investigated the effect of acute stress symptoms and social support from peers and family on posttraumatic stress symptoms, depression, and posttraumatic growth one year after being dispatched. We found that dispatched fire fighters experienced posttraumatic growth as well as posttraumatic stress symptoms following disaster work. Moreover, social support from peers was positively associated with professional growth as a disaster worker, whereas social support from family positively associated with gratitude. These results imply that it is useful to take into consideration supporting the posttraumatic growth of fire fighters as an opportunity for professional growth with respect to stress management programs as well as relieving posttraumatic symptoms with early intervention.

Melanin synthesis inhibitors from Balanophora fungosa.

Tyrosinase, trypsin, and tryptase are known to play important roles in melanin production of human skin. This paper describes the study of the inhibitory effect of Balanophora fungosa on melanin. The 50% EtOH extract obtained from B. fungosa indicated an inhibitory effect on mushroom tyrosinase activity with an IC(50) value of 15 µg/mL. Bioassay-guided fractionation of the active extract resulted in the isolation of four known compounds. Their structures were identified as 1-O-(E)-caffeoyl-3-O-galloyl-4,6-(S)-HHDP-ß-d-glucopyranose (1), 1-O-(E)-caffeoyl-3,4,6-tri-O-galloyl-ß-d-glucopyranose (2), caffeoyl-ß-d-glucopyranose (3), and abietin (4) on the basis of spectroscopic analyses and comparison of their spectral data with those in the literature. Compounds 1 and 2 prevented pigmentation of melanin in a three-dimensional cultured human skin model. Furthermore, compounds 1 and 2 indicated inhibitory activities against trypsin and tryptase.

Antihypertensive effect of enzymatic hydrolysate of collagen and Gly-Pro in spontaneously hypertensive rats.

Continuous oral feeding of enzymatic hydrolysate of porcine skin collagen showed an antihypertensive effect in spontaneously hypertensive rats (SHRs). We isolated an angiotensin I-converting enzyme (ACE) inhibitory peptide, Gly-Phe-Hyp-Gly-Pro (IC(50)=91 microM), from the hydrolysate, but the ACE inhibitory activities of the other peptides isolated were weak. Although the ACE inhibitory activity of Gly-Pro (IC(50)=360 microM) was not potent, Gly-Pro exists in collagen as a large number of repeated sequences. We then examined the antihypertensive effect of Gly-Pro. Orally administered Gly-Pro at 500 mg/kg significantly decreased the blood pressure of SHRs, and at 50 mg/kg it also showed a tendency to lower the blood pressure. Oral administration of Gly-Phe-Hyp-Gly-Pro (10 or 30 mg/kg) also decreased the blood pressure of SHRs.

N-[(Dihydroxyphenyl)acyl]serotonins as potent inhibitors of tyrosinase from mouse and human melanoma cells.

A series of N-acyl derivatives of tyramine, tryptamine, and serotonin were synthesized and tested on anti-melanogenic activity. The serotonin derivatives such as N-caffeoylserotonin (3) and N-protocatechuoylserotonin (9) were inhibitory to tyrosinase from mouse B16 and human HMV-II melanoma cells, while the corresponding derivatives of tryptamine and 5-methoxytryptamine were almost inactive or less active than the serotonin derivatives. The inhibitory activity of the serotonin derivatives increased with increasing number of phenolic hydroxyl groups in the acyl moiety. Melanin formation in the culture of B16 cells was suppressed by 3 and 9 with no cytotoxicity in the concentration range tested (IC(50)=15, 3 and 111muM for 3, 9, and kojic acid, respectively). Thus the N-acylserotonin derivatives having a dihydroxyphenyl group are potential anti-melanogenic agents. Their inhibition of tyrosinase is primarily performed through the 5-hydroxyindole moiety and further strengthened by the phenolic hydroxyl groups in the acyl moiety.

Antihypertensive effect of an extract of Passiflora edulis rind in spontaneously hypertensive rats.

Orally administered methanol extract of Passiflora edulis rind (10 mg/kg or 50 mg/kg) or luteolin (50 mg/kg), which is one of consistent polyphenols of the extract, significantly lowered systolic blood pressure in spontaneously hypertensive rats (SHRs). Quantitative analysis by liquid chromatography tandem mass spectrometry (LC-MS/MS) showed that the extract contained 20 microg/g dry weight of luteolin and 41 microg/g dry weight of luteolin-6-C-glucoside. It also contained gamma-aminobutyric acid (GABA, 2.4 mg/g dry weight by LC-MS/MS or 4.4 mg/g dry weight by amino acid analysis) which has been reported to be an antihypertensive material. Since the extract contained a relatively high concentration of GABA, the antihypertensive effect of the extract in SHRs might be due mostly to the GABA-induced antihypertensive effect and partially to the vasodilatory effect of polyphenols including luteolin.

Luteolin inhibits endothelin-1 secretion in cultured endothelial cells.

We discovered that luteolin, a typical flavonoid contained in various kinds of plants, inhibits the secretion and gene expression of endothelin-1 (ET-1), a potent vasoconstrictor regulating blood pressure, in porcine aortic endothelial cells. Its ED50 was about 10 microM. In addition, the inhibition of ET-1 by a glycoside compound of luteolin (luteolin-6-C-glucoside) was weak.

A synthetic polymer, poly(2-methacryloyloxyethyl phosphorylcholine-co-n-stearyl methacrylate), stimulates insulin release from RINm5F insulinoma cells.

A water-soluble phospholipid-like polymer, poly(2-methacryloyloxyethyl phosphorylcholine-co-n-stearyl methacrylate) (PMC(18), average molecular weight = 4.3 x 10(4)), at a concentration (0.5-5 mg/ml) showing no inhibition of cell proliferation, stimulated insulin release from RINm5F rat insulinoma cells in a concentration- and time-related manner. But poly(2-methacryloyloxyethyl phosphorylcholine) and other synthetic phospholipid-like polymers failed to stimulate insulin release.

Angiotensin I-converting enzyme inhibitory activity and insulin secretion stimulative activity of fermented fish sauce.

Angiotensin I-converting enzyme (ACE) inhibitory peptides, Ala-Pro, Lys-Pro, and Arg-Pro, were isolated from fermented fish sauce. Five other proline-containing dipeptides having weak ACE inhibitory activity were also isolated from the fermented fish sauce. Orally administered Lys-Pro showed a tendency to lower the blood pressure of spontaneously hypertensive rats. As fermented anchovy sauce also stimulated insulin secretion by cultured RINm5F insulinoma cells, the sauce may be useful as a source of biologically active substances.

Enhanced production of matrix metalloproteinase-2 in human head and neck carcinomas is correlated with lymph node metastasis.

Matrix metalloproteinase (MMP)-2 and -9 degrade type IV collagen, which is one of the major components of the basement membrane in normal tissue and expressed in the surroundings of the cancer nest in squamous cell carcinoma. The degeneration of type IV collagen is an essential step in the metastasis to lymph nodes and distant organs. In this study, we examined MMP-2 and -9 levels of cancer tissue and serum obtained from patients with head and neck squamous cell carcinoma (HNSCC) in order to evaluate the relationship between the clinicopathologic features and MMPs. We examined the production of MMP-2 and -9 in cancer tissue homogenates of 73 patients who had HNSCC and the serum MMP levels of 16 patients with HNSCC and 8 healthy volunteers. We also studied the localization of MMP-2 in the carcinoma using an immunohistochemical approach. The concentrations of MMP-2 and -9 in the tissue homogenates and serum were measured by means of a sandwich enzyme immunoassay using a monoclonal antibody. Immunohistochemical analyses were performed with monoclonal antibody to MMP-2. The concentration of MMP-2 in the tumor tissue homogenates was unrelated to tumor size, but that in patients with lymph node metastases was significantly higher than in those without lymph node metastases. The concentration of MMP-9 was unrelated to lymph node metastasis and tumor size. The levels of both MMP-2 and -9 in serum were unrelated to lymph node metastasis. Immunohistochemistry indicated that MMP-2 was mainly expressed in cancer cells. Because MMP-2 degrades type IV collagen, the level of MMP-2 in carcinomas may be a useful indicator of the degree of invasion and metastasis.

In Vitro and in Vivo Anti-platelet Effects of Enzymatic Hydrolysates of Collagen and Collagen-related Peptides.

Collagen-related peptides, Gly-Pro-Arg and its analogues, were examined for their inhibitory effects on platelet aggregation induced by the addition of ADP. Human platelet aggregation was suppressed by more than 50% with each of Gly-Pro-Arg and such Gly-Pro-Arg-containing peptides as Gly-Pro-Arg-Gly, Gly-Pro-Arg-Gly-Pro, Gly-Pro-Arg-Pro-Pro, and Gly-Pro-Arg-Pro-Pro-Pro at a concentration of 0.3 mm. The inhibitory effects of these peptides were about 10 times higher in human PRP than in rat PRP. Other Gly-Pro-Arg analogues such as Sar-Pro-Arg, Gly-Pro-Lys, Gly-Ala-Arg, and Ala-Gly-Pro-Arg had no inhibitory effect at a concentration from 0.1 to 0.8 mm even in human PRP. Intravenous and oral administrations of Gly-Pro-Arg and enzymatic hydrolysates of collagen suppressed the decrease in platelet count for endotoxin-induced DIC in rats. Collagen itself has been regarded as a potent inducer of platelet aggregation, but these findings suggest that collagen-related peptides and enzymatic hydrolysates of collagen prevent platelet aggregation.