Parapyruvate Induces Neurodegeneration in C57BL/6JNarl Mice via Inhibition of the α-Ketoglutarate Dehydrogenase Complex.

Parapyruvate is a substance commonly found in commercial dietary supplements of calcium pyruvate (DSCP) that inhibits the α-ketoglutarate dehydrogenase complex (KGDHC) and has been shown to induce senescence in human Hs68 cells. However, it is unknown whether parapyruvate can induce neurodegeneration. In this study, the parapyruvate content in DSCP was converted to an equivalent dose for mice and administered to the C57BL/6JNarl mice at doses around the equivalent dose for 69 days, including 5, 50, and 500 mg/kg/day. The Morris water maze (MWM) task and the active avoidance test were conducted to assess the learning and memory ability in mice, and then brain tissues were collected for biochemical analyses. The results demonstrated that parapyruvate significantly impaired the learning and memory ability, decreased the KGDHC activity, and promoted the oxidative stress and acetylcholinesterase (AChE) activity in mice in a dose-dependent manner. Additionally, parapyruvate induced Tau and phosphorylated Tau (p-Tau) aggregation at dosages ≥5 mg/kg/day and increased the myelin basic protein (MBP) expression at a dosage of 500 mg/kg/day. These results suggest that the equivalent dose of parapyruvate can induce neurodegeneration in the C57BL/6JNarl mice.

Safety Assessment and Hepatic-Renal Protection of Cajanus cajan (L.) Millsp. Root and Its Soy Isoflavone Contents.

Cajanus cajan (L.) Millsp., also known as pigeon pea, has roots that have exhibited much pharmacological potential. The present study was conducted to assess the safe dose of the ethanolic extract of C. cajan roots (EECR95) and to analyze the main soy isoflavones contents. In vitro, we investigated the mutagenicity and cytotoxic effect of EECR95 on Salmonella typhimurium-TA98 and TA100 (by Ames tests) and RAW 264.7, L-929, and HGF-1 cell lines (by MTT tests) for 24 h of incubation. We found no mutagenic or cytotoxic effects of EECR95. After administration of 0.2 or 1.0 g/kg bw of EECR95 to both male and female Wistar rats for 90 days, there were no significant adverse effects on the behaviors (body weight, water intake, and food intake), organ/tissue weights, or immunohistochemical staining, and the urine and hematological examinations of the rats were within normal ranges. EECR95 potentially decreases renal function markers in serum (serum uric acid, BUN, CRE, and GLU) or liver function markers (cholesterol, triglyceride, and glutamic-pyruvate-transaminase (GPT)). We also found that EECR95 contained five soy isoflavones (genistein, biochanin A, daidzein, genistin, and cajanol), which may be related to its hepatorenal protection. Based on the high dose (1.0 g/kg bw) of EECR95, a safe daily intake of EECR95 for human adults is estimated to be 972 mg/60 kg person/day.

Insulin sensitizer and antihyperlipidemic effects of Cajanus cajan (L.) millsp. root in methylglyoxal-induced diabetic rats.

Cajanus cajan (L.) Millsp., known as pigeon pea, is one of the major grain legume crops of the tropical world. It recognizes as an ethnomedicine to possess various functions, such as helping in healing wound and cancer therapy. We investigated whether 95% ethanol extracts from C. cajan root (EECR) protect against methylglyoxal (MGO)-induced insulin resistance (IR) and hyperlipidemia in male Wistar rats and explored its possible mechanisms. The hypoglycemic potential of EECR was evaluated using α-amylase, α-glucosidase activities, and advanced glycation end products (AGEs) formation. For in vivo study, the rats were divided into six groups and orally supplemented with MGO except for Group 1 (controls). Group 2 was supplemented with MGO only, Group 3: MGO + metformin, Group 4: MGO + Low dose-EECR (L-EECR; 10 mg/kg bw), Group 5: MGO + Middle dose-EECR (M-EECR; 50 mg/kg bw), and Group 6: MGO + High dose-EECR (H-EECR; 100 mg/kg bw). EECR possessed good inhibition of α-glucosidase, α-amylase activities, and AGEs formation (IC50 = 0.12, 0.32, and 0.50 mg/mL), respectively. MGO significantly increased serum levels of blood glucose (GLU), glycosylated hemoglobin, homeostasis model assessment of IR, AGEs, lipid biochemical values, and atherogenic index, whereas EECR decreased these levels in a dose-dependent manner. EECR can also act as an insulin sensitizer, which significantly decreased (47%, P < 0.05) the blood GLU levels after intraperitoneal injection of insulin in the insulin tolerance tests. The hypoglycemic and antihyperlipidemic mechanisms of EECR are likely through several possible pathways including the inhibition of carbohydrate-hydrolyzing enzymes (α-glucosidase and α-amylase) and the enhancement of MGO-trapping effects on inhibition of AGEs formation.

Effects of Cajanus cajan (L.) millsp. roots extracts on the antioxidant and anti-inflammatory activities.

Cajanus cajan (L.) Millsp., also named pigeon pea, is widely grown in the tropics and the subtropics. C. cajan roots (CR) and ribs stewed in hot water have been used as a traditional medicine in various cultures to treat diabetes. The purpose of this study was to determine the functional components of hot water (WCR) and 50%, 95% ethanol extracts (EECR50 and EECR95) from CR, then evaluating their antioxidant and anti-inflammatory effects. The results indicated that EECR95 had higher polyphenol, especially the isoflavones (e.x. daidzein, genistein, and cajanol) than those of the other extracts, and it also exhibited the most potent anti-oxidative activities by in vitro antioxidant assay. In the lipopolysaccharide-stimulated RAW 264.7 cells, we found that EECR95 significantly decreased intracellular reactive oxygen species and significantly enhanced the activities of superoxide dismutase and catalase. Mechanism studies showed that EECR95 mainly activated nuclear factor (NF) erythroid 2-related factor 2/antioxidant protein heme oxygenase-1 and inhibited nuclear factor kappa B (NF-κB) signaling pathway, and thus exhibited antioxidant and anti-inflammatory effects. Overall, this study suggests that CR may have the potential to be developed as a biomedical material and that genistein, which has relatively high uptakes (3.44% for the pure compound and 1.73% for endogenous genistein of EECR95) at 24 h of incubation with RAW 264.7 cells, could be the main active component of CR.

Safety and efficacy of tyrosinase inhibition of Paeonia suffruticosa Andrews extracts on human melanoma cells.

INTRODUCTION: The development of tyrosinase inhibitors is a hot research topic. Recently, the Chinese herb Paeonia suffruticosa Andrews, commonly named as Cortex Moutan (CM), was reported as being capable of reducing melanogenesis. We developed an A2058 human melanoma cell model to test the safety and efficacy of tyrosinase inhibition. The aim was to further clarify the bioactivities of CM extracts and paeonol for the purpose of skin whitening. METHODS: The 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity, total polyphenol and flavonoid contents, and in vitro tyrosinase inhibitory effects of water and ethanol CM extracts were determined. Cellular inhibitions of tyrosinase and melanin production were also evaluated. RESULTS: Water and ethanol CM extracts were both shown to have strong DPPH scavenging abilities in a dose-dependent manner. The polyphenol content was higher in the ethanol CM extract compared to the water extract, while the flavanone content was comparable. Kinetic analyses revealed that the ethanol CM extract and paeonol are noncompetitive tyrosinase inhibitors. The cellular melanin content and l-DOPA oxidation assays demonstrated that the ethanol CM extract was an appropriate alternative whitening agent to paeonol and arbutin in ultraviolet-induced A2058 human melanoma cells. CONCLUSION: The results of this study suggest that a human cell model is more suitable for determining tyrosinase activity than mouse cell models for determining cellular tyrosinase activity and melanin production. The ethanol CM extract was also confirmed as a promising ingredient in sun protection and skin whitening cosmetics. Future work should focus on melanogenesis-related gene expressions.

Anti-Fatigue, Antioxidation, and Anti-Inflammatory Effects of Eucalyptus Oil Aromatherapy in Swimming-Exercised Rats.

Eucalyptus globulus possesses important pharmacological activities, including antioxidant and anti-inflammatory effects. We investigated the anti-fatigue, antioxidant, and anti-inflammatory effects of eucalyptus essential oil after swimming exercise using an animal model. Male Sprague­ Dawley rats were administered eucalyptus oil (200 µL/h) daily via inhalation (15 min), and anti-fatigue effects were assessed following eucalyptus essential oil administration for 2 or 4 weeks when forced to swim until exhaustion while carrying ~5% body weight-equivalent. To assess antioxidant and anti-inflammatory effects, control and oil-treated groups were subjected to swimming, which was intensified from 90 min to 120 min daily over 4 weeks, with non-swimming groups included as controls. The 2- and 4-week-treated rats increased their swimming-to-exhaustion time by 46 s and 111 s, respectively. Additionally, lactate (LA), creatine kinase (CK), and lactate dehydrogenase (LDH) activities increased significantly in the non-treated swimming relative to levels observed in the non-swimming groups (P < 0.05); however, no significant differences in these markers were observed between the treated groups. The anti-fatigue effects were related to LA clearance and reduced LDH and CK concentrations. Moreover, compared to the corresponding levels in the non-swimmers, the non-treated swimmers showed markedly elevated levels of liver malondialdehyde (MDA), xanthine oxidase (XO), and other factors, but significantly decreased (P < 0.05) glutathione (GSH) concentrations. However, compared with that of the non-swimmer group, the treated swimming group showed no significant changes in these levels (P > 0.05), suggesting stable XO and MDA production and maintenance of GSH levels. These results suggested that eucalyptus oil aromatherapy increased rat swimming performance and antioxidant capacity and decreased oxidative damage and inflammatory reactions in tissues, indicating good anti-fatigue, antioxidant, and anti-inflammatory effects after high-intensity endurance exercise.

Antioxidant Properties of Essential Oil Extracted from Pinus morrisonicola Hay Needles by Supercritical Fluid and Identification of Possible Active Compounds by GC/MS.

Pine (Pinus morrisonicola Hay, PM) needles have been used as folk medicine for their antihypertension and lipid-lowering effects. As supercritical fluid extraction (SFE) is considered an ideal technique for the extraction of essential oil from plant materials, the present work investigated the optimal SFE conditions and the protective effects of different resulting fractions of PM needles on lipid peroxidation and foam cell production in macrophages. Nine PM needle extracts (PME1-9) were obtained in 1%-4% yields using different SFE conditions, of which PME1 had the lowest yield (1.1%) and PME3 the highest (3.9%). PME3 exhibited lower cytotoxic effects and stronger inhibition of lipid peroxidation and formation of foam cell in RAW 264.7 macrophages than those of other PME extracts. PME3-1 purified from PME3 by column and thin layer chromatography inhibited LDL oxidation more effectively than did PME3 in a cell-free system oxidized by Cu(2+). PME3-1 dose-dependently (25-100 µg/mL) decreased conjugated diene levels and foam cell formation induced by ox-LDL. GC/MS analyses revealed that 1-docosene, neophytadiene, and methyl abietate were increased 5.2-, 1.7- and 4.3-fold in PME3-1 relative to PME3. A new hydrocarbon compound, cedrane-8,13-diol, was identified in PME3-1. Overall, the present study demonstrates the optimal extraction conditions of SFE of PM and identifies the most potent antioxidant fractions and possible active compounds in PM.

Acteoside and 6-O-acetylacteoside downregulate cell adhesion molecules induced by IL-1beta through inhibition of ERK and JNK in human vascular endothelial cells.

Acteoside, an active phenylethanoid glycoside of many medicinal plants and bitter tea, displays anti-inflammatory properties in vitro. However, it is unclear whether acteoside and similar compounds may inhibit the expression of cell adhesion molecules (CAMs), which plays a role in the pathogenesis of atherosclerosis and inflammation. Here, we found that acteoside, isoacteoside, and 6-O-acetylacteoside inhibited IL-1beta-activated expression of intercellular CAM-1 (ICAM-1) and vascular CAM-1 (VCAM-1) in human umbilical vein endothelial cells (HUVECs); the inhibitory potency was as follows: 6-O-acetylacteoside > acteoside > isoacteoside. Acteoside and 6-O-acetylacteoside also dose-dependently inhibited VCAM-1 gene promoter activity in IL-1beta-activated HUVECs. The inhibition of acteoside and 6-O-acetylacteoside on IL-1beta-activated expression of CAMs was manifested by decreased phosphorylation of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK). These results indicate that acteoside and 6-O-acetylacteoside may exert anti-inflammatory activities in vascular endothelium by inhibiting the expression of CAMs, primarily through decreased phosphorylation of ERK and JNK.

Antiproliferative and antimetastatic effects of the ethanolic extract of Phellinus igniarius (Linnearus: Fries) Quelet.

AIM OF THIS STUDY: Phellinus igniarius (Linnearus: Fries) Quelet (Phellinus igniarius) has been used in oriental countries for treatment of various diseases including cancer. However, it is unclear how Phellinus igniarius exerts anticancer effects. MATERIALS AND METHODS: In this study the ethanolic extract from the fruiting body of Phellinus igniarius (EEPI) was used to evaluate the antiproliferative and antimetastatic effects in human hepatocarcinoma SK-Hep-1 cells and rat heart vascular endothelial cells (RHE cells). RESULTS: We found that EEPI inhibited the proliferation of both cell lines in a dose-dependent manner, and the IC50 values at 48 h were 72 and 103 microg/ml for SK-Hep-1 cells and RHE cells, respectively. EEPI at non- or sub-cytotoxic concentrations (25-100 microg/ml) markedly inhibited the migration and invasion of SK-Hep-1 cells. EEPI added at 25 microg/ml significantly decreased the secretion of matrix metalloproteinase-2 (MMP-2) (49%, p<0.01) and vascular endothelial growth factor (VEGF) (13%, p<0.05) in SK-Hep-1 cells. EEPI at 25 microg/ml completely inhibited matrigel-induced tube formation in RHE cells. Importantly, EEPI (25 or 50 microg/ml) in combination with oxaliplatin (Oxa) or 5-flurouracil (5-FU) synergistically inhibited the proliferation of SK-Hep-1 cells. CONCLUSION: These results demonstrate the antiproliferative and antimetastatic effects of EEPI in vitro and the potential of EEPI as an adjuvant for chemotherapy.

Induction of apoptosis in human hepatoma cells by mycelia of Antrodia camphorata in submerged culture.

The effect of methanolic extracts of mycelia (MEM) from Antrodia camphorata (Polyporaceac, Aphyllophorales) of submerged culture (ACSC) on the inhibition of cell viability and the mechanism of MEM-induced cytotoxic in hepatoma cells were investigated. The IC(50) of MEM on the cytotoxicity of HepG2 (wild type p53) and Hep3B (delete p53) were 49.5 and 62.7 microg/ml, respectively, on 48 h incubation. There is no observable cytotoxicity of MEM in Chang liver cells and rat primary hepatocytes at the concentration of 100 microg/ml. Cell cycle analysis revealed that MEM induced apoptosis on HepG2 via G0/G1 cell cycle arrest. MEM (100 microg/ml) treated HepG2 and Hep3B for 72 h, the apoptotic cells were 98.3 and 39.5%, respectively. The activities of caspase-3, -8 and -9 in HepG2 induced by MEM (50 microg/ml) were increased 5.3, 6.7 and 2.2-fold, respectively. MEM-induced apoptotic cell death was accompanied by up-regulation of caspase-3 and -8 in HepG2 cells. Combined treatment with MEM and caspase-3, -8 and -9 inhibitors, the caspase-3 and -8 inhibitors were accounting for 63 and 47% inhibition in MEM-induced apoptosis, respectively; however, caspase-9 inhibitor exhibited no obvious inhibition effect on the apoptosis percentage (p>0.05). The results indicated that MEM induced HepG2 apoptosis through activation of caspase-3 and -8 cascades and regulation of the cell cycle progression to inhibit hepatoma cells proliferation.