Putative Effect of Extract on Enzyme Activities Participating in Lipid and Carbohydrate Digestion Processes.

Excessive calorie intake is generally accepted as a primary cause of metabolic syndrome, and therefore a well-balanced diet and moderate exercise can be expected to be the most effective measures to avoid the disorder of energy utilization and storage. Furthermore, as any other way to improve the disorder of energy balance, it may be effective to delay and lower the digestion and/or absorption of energy sources, lipids, and carbohydrates. As a primary screening of effective substances to delay and lower the digestion and absorption processes among natural materials, the protein-deprived extract was prepared from blue-green algae , and the effect of this extract on lipase and α-glucosidase activities was examined.

Suppressive effect of Okara on intestinal lipid digestion and absorption in mice ingesting high-fat diet.

Soymilk residue Okara is paid attention as a low-calorie foodstuff effective for the amelioration of obesity, and expected to have the potential ability to reduce calorie intake by suppressing the digestion and absorption of high-calorie nutrients in the intestinal tract. Then, the direct effect of Okara extract on lipase activity was examined, and this extract was shown to inhibit the enzyme activity. On the other hand, the spray-dried powder of Okara extract was suspended in a drinking water and given to mice fed with a high-fat diet.

Lotus Root Extract Stimulates BDNF Gene Expression Through Potential Mechanism Depending on HO-1 Activity in C6 Glioma Cells.

Polyphenolic compounds have been suggested to be involved in the preservation of neural function via the production of neurotrophic factors in the brain. The nonedible joint part of lotus root (a rhizome of Nelumbo nucifera) has been reported to contain large amounts of polyphenolic compounds and, therefore, is expected to improve neural function by stimulating the production of brain-derived neurotrophic factor (BDNF) in glial cells. The effect of the aqueous extract prepared from the joint part of lotus root on BDNF gene expression was examined in C6 glioma cells as an in vitro model.

Fermented Brown Rice Extract Stimulates BDNF Gene Transcription in C6 Glioma Cells: Possible Connection with HO-1 Expression.

Fermented brown rice with Aspergillus oryzae, designated as FBRA, is known to be commercially available dietary fiber-rich food, which is appreciated as prebiotics to improve intestinal microflora, and also shown to contain various biologically active substances including polyphenolic compounds. On the other hand, polyphenolic compounds have been suggested to stimulate the expression of brain-derived neurotrophic factor (BDNF) gene in connection with the expression of heme oxidase-1 (HO-1) gene in glial cells, thus resulting in the augmentation of BDNF production in the brain, thereby being anticipated to have a putative effect on the brain function. Then, the effect of FBRA extract on HO-1 and BDNF messenger ribonucleic acid (mRNA) levels in C6 glioma cells was examined, and the extract was shown to stimulate both HO-1 and BDNF gene transcription in the glioma cells.

Soy Pulp Extract Inhibits Angiotensin I-Converting Enzyme (ACE) Activity In Vitro: Evidence for Its Potential Hypertension-Improving Action.

Soy pulp, called "okara" in Japanese, is known as a by-product of the production of bean curd (tofu), and expected to contain a variety of biologically active substances derived from soybean. However, the biological activities of okara ingredients have not yet been fully understood, and the effectiveness of okara as a functional food seems necessary to be further evaluated. Then the effect of okara extract on angiotensin I-converting enzyme (ACE) activity was examined in vitro, and the extract was shown to cause the inhibition of ACE activity in a manner depending on its concentration.

Fermented Brown Rice Extract Causes Apoptotic Death of Human Acute Lymphoblastic Leukemia Cells via Death Receptor Pathway.

Mixture of brown rice and rice bran fermented with Aspergillus oryzae, designated as FBRA, has been reported to reveal anti-carcinogenic and anti-inflammatory effects in rodents. Then, to test its potential anti-cancer activity, the aqueous extract was prepared from FBRA powder, and the effect of this extract on human acute lymphoblastic leukemia Jurkat cells was directly examined. The exposure to FBRA extract reduced the cell viability in a concentration- and time-dependent manner.

Spirulina non-protein components induce BDNF gene transcription via HO-1 activity in C6 glioma cells.

Blue-green algae are known to contain biologically active proteins and non-protein substances and considered as useful materials for manufacturing the nutritional supplements. Particularly, Spirulina has been reported to contain a variety of antioxidants, such as flavonoids, carotenoids, and vitamin C, thereby exerting their protective effects against the oxidative damage to the cells. In addition to their antioxidant actions, polyphenolic compounds have been speculated to cause the protection of neuronal cells and the recovery of neurologic function in the brain through the production of brain-derived neurotrophic factor (BDNF) in glial cells.

Polyamines cause elevation of steroid 5α-reductase mRNA levels by suppressing mRNA degradation in C6 glioma cells.

Polyamines are widely distributed in living organisms, and considered to play a potential role in various cellular processes. The effects of polyamines on gene expression as well as cell proliferation have been suggested to be closely associated with the physiological and pathological functions. However, it seems necessary to investigate their potential roles in the regulation of cellular metabolism and functions.

Trichostatin A enhances glutamate transporter GLT-1 mRNA levels in C6 glioma cells via neurosteroid-mediated cell differentiation.

The neurotoxic effects of excitatory amino acids (EAAs) are suggested to be connected with the chronic loss of neuronal cells, thereby being responsible for the age-related neurodegenerative diseases. Therefore, it seems conceivable that the excitatory amino acid transporters may contribute to the protection of neuronal cells against the excitotoxic damage by facilitating the removal of EAAs from the brain tissue. On the other hand, previous studies have suggested that glial cell differentiation may be involved in the protection and recovery of neural function probably through the elevation of BDNF gene expression in the brain.

Extract of fermented brown rice induces apoptosis of human colorectal tumor cells by activating mitochondrial pathway.

Brown rice fermented with Aspergillus oryzae, designated as FBRA, is a dietary fiber-rich food, and fully appreciated as one of the prebiotics, which are generally considered to be beneficial to the health of the body, because of stimulating the growth and/or the activity of bacteria in the digestive system. To assess the effectiveness of FBRA as a functional food, the direct effect of FBRA extract on human colorectal tumor cells was examined. The exposure of HCT116 cells to FBRA extract reduced their viabilities in a concentration-dependent manner, and the reduction of the cell viability might be attributed to the induction of apoptosis probably through the oxidative damage to the cells.

Histone deacetylase inhibitors promote neurosteroid-mediated cell differentiation and enhance serotonin-stimulated brain-derived neurotrophic factor gene expression in rat C6 glioma cells.

Progesterone treatment has previously been reported to promote the differentiation of glial cells probably through the production of 5alpha-reduced neurosteroids, resulting in the enhancement of serotonin-stimulated brain-derived neurotrophic factor (BDNF) gene expression, which is considered to contribute to the survival, regeneration, and plasticity of neuronal cells in the brain and hence has been suggested to improve mood disorders and other symptoms in depressive patients. Based on these previous observations, the effects on glial cells of histone deacetylase (HDAC) inhibitors, which are known as agents promoting cell differentiation, were examined using rat C6 glioma cells as a model for in vitro studies. Consequently, trichostatin A (TSA), sodium butyrate (NaB), and valproic acid (VPA) stimulated glial fibrillary acidic protein (GFAP) gene expression, and their stimulatory effects on GFAP gene expression were inhibited by treatment of these cells with finasteride, an inhibitor of the enzyme producing 5alpha-reduced neurosteroids.

Possible relation of hemin-induced HO-1 expression to the upregulation of VEGF and BDNF mRNA levels in rat C6 glioma cells.

Glial cells are generally considered to contribute to retaining the integrity of neural function through the protection of neuronal cells against neurodegenerative insults and also expected to play a potential role in the protection of cerebrovascular systems from various toxic insults of hemorrhaged blood, thus proposing a possible implication of glial cells in the recovery of brain function from the damage caused by cerebral hemorrhage. Based on this hypothetical idea, the direct effect of hemin on the expression of genes encoding heme oxygenase-1 (HO-1), vascular endothelial growth factor (VEGF), and brain-derived neurotrophic factor (BDNF) in glial cells was examined using rat C6 glioma cells as an in vitro model system. Hemin elevated both HO-1 and VEGF mRNA levels in the glioma cells at the concentration causing no critical damage to the cells, and the elevation of BDNF mRNA levels was also observed by exposing the cells to hemin under the same conditions.