Konjac Glucomannan Attenuated Triglyceride Metabolism during Rice Gruel Tolerance Test.

In a recent study, we showed that konjac glucomannan (KGM) inhibits rice gruel-induced postprandial increases in plasma glucose and insulin levels. To extend this research, we investigated the effects of KGM addition to rice gruel on pre- and postprandial concentrations of circulating lipoprotein lipase (LPL), glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1), hepatic triglyceride lipase (HTGL), free fatty acids (FFA), and triglycerides (TG). A total of 13 Japanese men, without diabetes, dyslipidemia, or gastrointestinal diseases, interchangeably ingested rice gruel containing no KGM (0%G), rice gruel supplemented with 0.4% KGM (0.4%G), and rice gruel supplemented with 0.8% KGM (0.8%G), every Sunday for 3 weeks. Blood samples were obtained at baseline and at 30, 60, and 120 min after ingestion to measure the abovementioned lipid parameters. Lipid parameters showed small, but significant, changes. Significant reductions were found in circulating FFA levels among all participants. Circulating TG levels significantly declined at 30 min and then remained nearly constant in the 0.8%G group but exhibited no significant difference in the 0%G and 0.4%G groups. Although circulating levels of LPL and GPIHBP1 significantly decreased in the 0%G and 0.4%G groups, they increased at 120 min in the 0.8%G group. Participants in the 0%G and 0.4%G groups showed significant decreases in circulating HTGL levels, which was not observed in the 0.8%G group. Our results demonstrate the novel pleiotropic effects of KGM. Supplementation of rice gruel with KGM powder led to TG reduction accompanied by LPL and GPIHBP1 elevation and HTGL stabilization, thereby attenuating TG metabolism.

Elevated phosphatidylserine-specific phospholipase A1 level in hyperthyroidism.

OBJECTIVES: Although a single nucleotide polymorphism in a specific receptor for lysophosphatidylserine, a lysophospholipid mediator involved in the immune system, is reportedly associated with Graves' disease, the association between lysophosphatidylserine and thyroid disorders remains to be elucidated. Therefore, we aimed to investigate the association between the level of phosphatidylserine-specific phospholipase A1 (PS-PLA1), which produces lysophosphatidylserine, and thyroid disorders. METHODS: We measured serum PS-PLA1 levels in the patients with various thyroid disorders (n = 120) and normal subjects (n = 58). RESULTS: We observed that the serum PS-PLA1 levels were higher in the subjects with Graves' disease, subacute thyroiditis, or silent thyroiditis, while they were not modulated in the patients with hypothyroidism. The serum PS-PLA1 levels were strongly correlated with the levels of thyroid hormones, especially in the subjects with Graves' disease. Moreover, we found that the serum PS-PLA1 levels were lowered by treatment with anti-thyroid reagents in subjects with Graves' disease and that the changes in PS-PLA1 were strongly correlated with those in thyroid hormones. CONCLUSION: These results suggest that PS-PLA1 might be a novel target in the treatment of hyperthyroidism, especially Graves' disease, and that its measurement might be useful as a supplementary diagnostic test for thyroid function.

Selenium enrichment of broccoli sprout extract increases chemosensitivity and apoptosis of LNCaP prostate cancer cells.

BACKGROUND: Broccoli is a Brassica vegetable that is believed to possess chemopreventive properties. Selenium also shows promise as an anticancer agent. Thus, selenium enrichment of broccoli has the potential to enhance the anticancer properties of broccoli sprouts. METHOD: Selenium-enriched broccoli sprouts were prepared using a sodium selenite solution. Their anticancer properties were evaluated in human prostate cancer cell lines and compared with those of a control broccoli sprout extract. RESULTS: Selenium-enriched broccoli sprouts were superior to normal broccoli sprouts in inhibiting cell proliferation, decreasing prostate-specific antigen secretion, and inducing apoptosis of prostate cancer cells. Furthermore, selenium-enriched broccoli sprouts but, not normal broccoli sprouts, induced a downregulation of the survival Akt/mTOR pathway. CONCLUSION: Our results suggest that selenium-enriched broccoli sprouts could potentially be used as an alternative selenium source for prostate cancer prevention and therapy.

Selenium supplementation and blood rheological improvement in Japanese adults.

In order to study the prevention effect of selenium in the development of cardiovascular disease, we investigated the effects of selenium supplementation on the blood rheological properties. Eleven healthy adults were administered with 200 microg of selenium in the form of selenium yeast per day for 1 wk. Before and after the supplementation, serum selenium concentration, glutathione peroxidase (GPx) activity, biochemical indices, and the blood fluidity of the subjects were measured. The blood fluidity was measured using a (microchannel array flow analyzer) by the passage time of 100 microL of heparinized whole blood through the microchannel array. The selenium supplementation significantly (p = 0.001) shortened the mean blood passage time from 44.0 +/- 5.7 to 37.5 +/- 2.8 s. Serum selenium concentration significantly (p = 0.008) increased from 109.8 +/- 10.2 to 124.5 +/- 16.7 microg/L. Meanwhile, the GPx activity did not increased significantly (p = 0.058). The mean GPx activity of the subjects before supplementation was 171.0 +/- 16.1 Deltammol NADPH/min/L and 180.9 +/- 17.8 Deltammol NADPH/min/L after supplementation. Factor analysis of the passage time and biochemical indices of the subjects showed that blood fluidity improvement was related to the metabolic modification of lipoproteins during the selenium supplementation. These results showed that selenium supplementation improved the blood fluidity, without increasing the GPx activity of the subjects.

Effects of hormone replacement therapy on circulating docosahexaenoic acid and eicosapentaenoic acid levels in postmenopausal women.

Hormone replacement therapy (HRT) has antiatherosclerotic effects of which the mechanism remains unclear. The ingestion of fish oil or other sources of n-3 polyunsaturated fatty acids has been included in comprehensive strategies to prevent atherosclerosis. Many epidemiologic studies have shown that the dietary intake of docosahexaenoic acid and eicosapentaenoic acid has antiatherosclerotic effects. We investigated the effect of HRT on plasma docosahexaenoic acid and eicosapentaenoic acid concentrations in postmenopausal women. Fifty-nine postmenopausal women, who received conjugated estrogens (0.625 mg/day) and medroxyprogesterone (2.5 mg/day) for 12 months, and 45 control postmenopausal women, who did not receive HRT, volunteered to participate in this study. Plasma docosahexaenoic acid and eicosapentaenoic acid concentrations were measured at baseline and at 6 and 12 months after the start of HRT. HRT significantly increased the plasma docosahexaenoic acid and eicosapentaenoic acid concentrations from 134 +/- 5 microg/ml and 69 +/- 4 microg/ml at baseline to 156 +/- 7 microg/ml and 85 +/- 7 microg/ml after 12 months (both p<0.01). However, the control group showed no significant change in their plasma docosahexaenoic acid and eicosapentaenoic acid levels during the study. HRT increased plasma docosahexaenoic acid and eicosapentaenoic acid levels in postmenopausal women. We propose that the increase in docosahexaenoic acid and eicosapentaenoic acid may be partially responsible for the beneficial mechanisms by which HRT induces an antiatherosclerotic effect in postmenopausal women.

Type 1 iodothyronine deiodinase in the house musk shrew (Suncus murinus, Insectivora: Soricidae): cloning and characterization of complementary DNA, unique tissue distribution and regulation by T(3).

The house musk shrew Suncus murinus (Insectivora: Soricidae) has been reported as having low thyroxine to 3,3'5-triiodothyronine (T(3)) converting activity in liver and kidney homogenates and was assumed to be type 1 iodothyronine deiodinase (D1)-deficient. To study whether this is due to structural abnormality of shrew D1, we cloned the cDNA and characterized the enzyme. The deduced amino acid sequence of shrew D1 was found to be highly homologous to other known D1s and the enzyme itself to have similar catalytic activity. However, unlike in other species, the D1 activity was detected only in liver. Moreover, the D1 activity in liver of the shrew was less than half of that in rat liver and its expression was not up-regulated by T(3). In contrast, a very high activity of D2 was demonstrated in brain and brown adipose tissue. The present study also revealed that the serum level of T(3) in the shrew was in the same range as these in other mammals. These results suggest that D2 contributes to the production and maintenance of T(3) levels in the house musk shrew.