Yeu-Ching Shi

Beneficial effects of Monascus purpureus NTU 568-fermented products: a review

Monascus-fermented products have been used in food, medicine, and industry dating back over a thousand years in Asian countries. Monascus-fermented products contained several bioactive metabolites such as pigments, polyketide monacolins, dimerumic acid, and γ-aminobutyric acid. Scientific reports showed that Monascus-fermented products proved to be effective for the management of blood cholesterol, diabetes, blood pressure, obesity, Alzheimer’s disease, and prevention of cancer development. This review article describes the beneficial effects about using Monascus-fermented products in human beings and animals.

Monascin from red mold dioscorea as a novel antidiabetic and antioxidative stress agent in rats and Caenorhabditis elegans

Monascin is a major yellow compound from red mold dioscorea. We investigated monascin to test whether this compound acts as an antidiabetic and antioxidative stress agent in diabetic rats and Caenorhabditis elegans. The mechanisms by which monascin exerts its action in vivo were also examined. Streptozotocin (STZ)-induced diabetic rats were given monascin at 30 mg/kg/day and sacrificed after 8 weeks. Blood glucose and serum insulin, triglyceride, total cholesterol, and high-density lipoprotein and antioxidative enzymes in the pancreas of rats were measured. In addition, monascin was evaluated for stress resistance and potential associated mechanisms in C. elegans. Throughout the 8-week experimental period, significantly lowered blood glucose, serum triglyceride, and total cholesterol and higher high-density lipoprotein levels were observed in monascin-treated rats. Monascin-treated rats showed higher serum insulin level, lower reactive oxygen species production, and higher activities of glutathione peroxidase, superoxide dismutase, and catalase in the pancreas compared to diabetic control rats. In addition, monascin significantly induced the hepatic mRNA levels of FOXO3a, FOXO1, MnSOD, and catalase in STZ-induced diabetic rats. Monascin-treated C. elegans showed an increased survival rate during oxidative stress and heat stress treatments compared to untreated controls. Moreover, monascin extended the life span under high-glucose conditions and enhanced expression of small heat shock protein (sHSP-16.2), superoxide dismutase (SOD-3), and glutathione S-transferase (GST-4) in C. elegans. Finally, we showed that monascin affected the subcellular distribution of the FOXO transcription factor DAF-16, whereas it was unable to enhance oxidative stress resistance in the daf-16 deletion mutant in C. elegans. Mechanistic studies in rats and C. elegans suggest that the protective effects of monascin are mediated via regulation of the FOXO/DAF-16-dependent insulin signaling pathway by inducing the expression of stress response/antioxidant genes, thereby enhancing oxidative stress resistance.

Anti-diabetic effects of Monascus purpureus NTU 568 fermented products on streptozotocin-induced diabetic rats.

Red-mold-fermented products have the unique ability to economically produce many secondary metabolites and are known to improve blood circulation. Diabetes mellitus is a chronic disease that is characterized by hyperglycemia caused by insufficient insulin action. In the current study, we examine the effect of Monascus purpureus NTU 568 fermented products on fasting blood glucose and oral glucose tolerance testing (OGTT) in streptozotocin-induced diabetic rats. After 8 weeks of being fed with red-mold-fermented products at a dose of 200 mg/kg, the experimental results indicate that oral administration of red-mold-fermented products can delay the development of the plasma glucose level in rats. A significant reduction was found in urine sugar and urine protein levels. The study scientifically validates the widely claimed use of red-mold-fermented products as an ethnomedicine to treat diabetes mellitus.

Antidepressant effect of GABA-rich monascus-fermented product on forced swimming rat model.

γ-Aminobutyric acid (GABA) has several well-known physiological functions including antihypertension and antidepression. In this research, we focus on the antidepressant effects of oral administration of GABA-rich Monascus-fermented product in depression animal model (forced swimming test, FST) by Sprague-Dawley rats, and try to find its possible mechanism in the brain monoamine system. GABA and the Monascus-fermented product (MFP) significantly decreased the duration of immobility time in a short-term test. In a long-term test, the antidepressant-like effect of MFP was better than that of GABA at the same dosage (2.6 mg/kg), and the efficacy of MFP was similar to that of fluoxetine. Moreover, GABA might recover the level of monoamines norepinephrine, dopamine (DA), and 5-hydroxytryptamine (5-HT) in hippocampus and normalize the turnover ratio of 5-HT and DA in hippocampus and amygdala. In addition to the functions of GABA, the MFP has more potential in decreasing the turnover ratio of DA in the frontal cortex and striatum to improve depressive symptoms.

Red mold, diabetes, and oxidative stress: a review

Type 2 diabetes is a major health concern and a rapidly growing disease with a modern etiology, which produces significant morbidity and mortality. The optimal management of type 2 diabetes aims to control hyperglycemia, hypertension, and dyslipidemia to reduce overall risks. Diabetes and its complications usually develop as oxidative stress increases. Monascus-fermented rice, also called red mold rice or red mold dioscorea are used in China to enhance food color and flavor. Red mold-fermented products are popular health foods that are considered to have antiobesity, antifatigue, antioxidation, and cancer prevention effects. This review article describes the antidiabetic and antioxidative stress effects on humans and animals of red mold-fermented products or their secondary metabolites.

Protective Efficacy of Selenite against Lead-Induced Neurotoxicity in Caenorhabditis elegans

Background Selenium is an essential micronutrient that has a narrow exposure window between its beneficial and toxic effects. This study investigated the protective potential of selenite (IV) against lead (Pb(II))-induced neurotoxicity in Caenorhabditis elegans. Principal Findings The results showed that Se(IV) (0.01 µM) pretreatment ameliorated the decline of locomotion behaviors (frequencies of body bends, head thrashes, and reversal ) of C. elegans that are damaged by Pb(II) (100 µM) exposure. The intracellular ROS level of C. elegans induced by Pb(II) exposure was significantly lowered by Se(IV) supplementation prior to Pb(II) exposure. Finally, Se(IV) protects AFD sensory neurons from Pb(II)-induced toxicity. Conclusions Our study suggests that Se(IV) has protective activities against Pb(II)-induced neurotoxicity through its antioxidant property.

Antihypertriglyceridemia and Anti-Inflammatory Activities of Monascus-Fermented Dioscorea in Streptozotocin-Induced Diabetic Rats

The rice fermented by Monascus, called red mold rice (RMR), and has a long tradition in East Asia as a dietary staple. Monascus-fermented dioscorea called red mold dioscorea (RMD) contains various metabolites to perform the ability of reducing oxidative stress and anti-inflammatory response. We used Wistar rats and induced diabetes by injecting streptozotocin (STZ, 65 mg/kg i.p.). RMD was administered daily starting six weeks after disease onset. Throughout the experimental period, significantly (P < .05) lowered plasma glucose, triglyceride, cholesterol, free fatty acid and low density lipoprotein levels were observed in the RMD-treated groups. The RMD-treated diabetic rats showed higher activities of glutathione disulfide reductase, glutathione reductase, catalase and superoxide dismutase (P < .05) in the pancreas compared with the diabetic control rats. RMD also inhibited diabetes-induced elevation in the levels of interleukin (IL)-1β, IL-6, interferon-γ and tumor necrosis factor-α. Pancreatic β-cells damaged by STZ in the RMD supplemented groups were ameliorated. The results of this study clearly demonstrated that RMD possesses several treatment-oriented properties, including the control of hyperglycemia, antioxidant effects, pancreatic β-cell protection and anti-inflammatory effects. Considering these observations, it appears that RMD may be a useful supplement to delay the development of diabetes and its complications.

Monascus-Fermented Dioscorea Enhances Oxidative Stress Resistance via DAF-16/FOXO in Caenorhabditis elegans

Background Monascus-fermented products are mentioned in an ancient Chinese pharmacopoeia of medicinal food and herbs. Monascus-fermented products offer valuable therapeutic benefits and have been extensively used in East Asia for several centuries. Several biological activities of Monascus-fermented products were recently described, and the extract of Monascus-fermented products showed strong antioxidant activity of scavenging DPPH radicals. To evaluate whether Monascus-fermented dioscorea products have potential as nutritional supplements, Monascus-fermented dioscorea’s modulation of oxidative-stress resistance and associated regulatory mechanisms in Caenorhabditis elegans were investigated. Principal Findings We examined oxidative stress resistance of the ethanol extract of red mold dioscorea (RMDE) in C. elegans, and found that RMDE-treated wild-type C. elegans showed an increased survival during juglone-induced oxidative stress compared to untreated controls, whereas the antioxidant phenotype was absent from a daf-16 mutant. In addition, the RMDE reduced the level of intracellular reactive oxygen species in C. elegans. Finally, the RMDE affected the subcellular distribution of the FOXO transcription factor, DAF-16, in C. elegans and induced the expression of the sod-3 antioxidative gene. Conclusions These findings suggest that the RMDE acts as an antioxidative stress agent and thus may have potential as a nutritional supplement. Further studies in C. elegans suggest that the antioxidant effect of RMDE is mediated via regulation of the DAF-16/FOXO-dependent pathway.

Selenite protects Caenorhabditis elegans from oxidative stress via DAF‐16 and TRXR‐1

SCOPE Selenium is an essential micronutrient. In the present study, trace amount of selenite (0.01 μM) was evaluated for oxidative stress resistance and potential associated factors in Caenorhabditis elegans. METHODS AND RESULTS Selenite-treated C. elegans showed an increased survival under oxidative stress and thermal stress compared to untreated controls. Further studies demonstrated that the significant stress resistance of selenite on C. elegans could be attributed to its in vivo free radical-scavenging ability. We also found that the oxidative and thermal stress resistance phenotypes by selenite were absent from the forkhead transcription factor daf-16 mutant worms. Moreover, selenite influenced the subcellular distribution of DAF-16 in C. elegans. Furthermore, selenite increased mRNA levels of stress-resistance-related proteins, including superoxide dismutase-3 and heat shock protein-16.2. Additionally, selenite (0.01 μM) upregulated expressions of transgenic C. elegans carrying sod-3::green fluorescent protein (GFP) and hsp-16.2::GFP, whereas this effect was abolished by feeding daf-16 RNA interference in C. elegans. Finally, unlike the wild-type N2 worms, the oxidative stress resistance phenotypes by selenite were both absent from the C. elegans selenoprotein trxr-1 mutant worms and trxr-1 mutants feeding with daf-16 RNA interference. CONCLUSION These findings suggest that the antioxidant effects of selenite in C. elegans are mediated via DAF-16 and TRXR-1.

Antioxidant Activity and Delayed Aging Effects of Hot Water Extract from Chamaecyparis obtusa var. formosana Leaves

The antioxidant activity and delayed aging effects of hot water extracts from leaves of Chamaecyparis obtusa var. formosana were investigated. Free radical, superoxide radical scavenging, and total phenolic content assays were employed to evaluate the in vitro activities of the extracts. In addition, in vivo assays using the nematode Caenorhabditis elegans were also performed in this study. The results showed that among all soluble fractions obtained from the extracts, the ethyl acetate-soluble fraction has the best in vitro and in vivo antioxidant activities. Moreover, it decreased significantly the deposition of lipofuscin (aging pigment) and extended the lifespan of C. elegans. Bioactivity-guided fractionation yielded six potent antioxidant constituents from the ethyl acetate-soluble fraction, namely, catechin, quercetin, quercetin-3-O-α-rhamnoyranoside, myricetin-3-O-α-rhamnoyranoside, vanillic acid, and 4-hydroxybenzoic acid. Quercetin-3-O-α-rhamnoyranoside pretreatment showed the highest survival of C. elegans upon juglone exposure. Taken together, the results revealed that hot water extracts from C. obtusa var. formosana leaves have the potential to be used as a source for antioxidant or delayed aging health food.