Vitamin C and glutathione supplementation: a review of their additive effects on exercise performance.

PURPOSE: This review aimed to investigate the effects of vitamin C and glutathione supplementation on exercise performance. METHODS: We conducted a literature search across the PubMed, Google Scholar, and Web of Science databases using the keywords vitamin C, glutathione, antioxidants, exercise, and oxidative stress. RESULTS: The effects of vitamin C supplementation on exercise performance and oxidative stress levels are inconsistent. Glutathione, with its diverse forms of supplementation and methods, presents mixed outcomes. Vitamin C and glutathione have deeply interconnected antioxidant functions and are mutually essential to each other. Research investigating the combined intake of these two substances, which are intricately linked biochemically, and their effects on exercise performance remain largely unexplored. CONCLUSION: Studies on the effects of vitamin C and glutathione intake on exercise have been conducted using diverse approaches; however, the results have not been consistent. Although an additive effect is anticipated with the combined intake of vitamin C and glutathione, research on this topic is currently insufficient, and further studies are required.

Enhancing Supplemental Effects of Acute Natural Antioxidant Derived from Yeast Fermentation and Vitamin C on Sports Performance in Triathlon Athletes: A Randomized, Double-Blinded, Placebo-Controlled, Crossover Trial.

This study investigated the acute effects of natural antioxidants, derived from yeast fermentation containing glutathione and dietary vitamin C supplementation, on metabolic function, skeletal muscle oxygenation, cardiac function, and antioxidant function during submaximal exercise in middle-aged triathlon athletes. Twelve participants (aged 49.42 ± 5.9 years) completed 90 min submaximal cycling trials corresponding to 70% maximal oxygen uptake with either vitamin C and glutathione (VitC+Glu), vitamin C (VitC), glutathione (Glu) supplementation, or placebo. Metabolic function (minute ventilation, oxygen uptake, carbon dioxide output [VCO2], respiratory exchange ratio [RER], oxygen pulse [O2pulse], carbohydrate oxidation, fat oxidation, and energy expenditure), skeletal muscle oxygenation (oxidized hemoglobin and myoglobin in skeletal muscle tissue, total hemoglobin and myoglobin in skeletal muscle tissue [tHb]), cardiac function (heart rate [HR], stroke volume [SV], cardiac output, end-diastolic volume, end-systolic volume, and ejection fraction), and antioxidant function parameters (blood lactate, superoxide dismutase, catalase, glutathione peroxidases, glutathione [GSH], diacron reactive oxygen metabolite [dROM], and biological antioxidant potential [BAP]) were measured during submaximal exercise and recovery. VCO2, RER, HR, blood lactate after exercise, and dROM were significantly lower, and O2pulse, tHb, and BAP were significantly higher for VitC+Glu than for the other trials (p < 0.05). In conclusion, combined vitamin C and glutathione supplementation was more effective in improving metabolic function, skeletal oxygenation, cardiac function, and antioxidant function during prolonged submaximal exercise in middle-aged triathletes.

System-level investigation of anti-obesity effects and the potential pathways of Cordyceps militaris in ovariectomized rats.

BACKGROUND: Cordyceps species have been used as tonics to enhance energy, stamina, and libido in traditional Asian medicine for more than 1600 years, indicating their potential for improving reproductive hormone disorders and energy metabolic diseases. Among Cordyceps, Cordyceps militaris has been reported to prevent metabolic syndromes including obesity and benefit the reproductive hormone system, suggesting that Cordyceps militaris can also regulate obesity induced by the menopause. We investigated the effectiveness of Cordyceps militaris extraction (CME) on menopausal obesity and its mechanisms. METHODS: We applied an approach combining in vivo, in vitro, and in silico methods. Ovariectomized rats were administrated CME, and their body weight, area of adipocytes, liver and uterus weight, and lipid levels were measured. Next, after the exposure of MCF-7 human breast cancer cells to CME, cell proliferation and the phosphorylation of estrogen receptor and mitogen-activated protein kinases (MAPK) were measured. Finally, network pharmacological methods were applied to predict the anti-obesity mechanisms of CME. RESULTS: CME prevented overweight, fat accumulation, liver hypertrophy, and lowered triglyceride levels, some of which were improved in a dose-dependent manner. In MCF-7 cell lines, CME showed not only estrogen receptor agonistic activity through an increase in cell proliferation and the phosphorylation of estrogen receptors, but also phosphorylation of extracellular-signal-regulated kinase and p38. In the network pharmacological analysis, bioactive compounds of CME such as cordycepin, adenine, and guanosine were predicted to interact with non-overlapping genes. The targeted genes were related to the insulin signaling pathway, insulin resistance, the MARK signaling pathway, the PI3K-Akt signaling pathway, and the estrogen signaling pathway. CONCLUSIONS: These results suggest that CME has anti-obesity effects in menopause and estrogenic agonistic activity. Compounds in CME have the potential to regulate obesity-related and menopause-related pathways. This study will contribute to developing the understanding of anti-obesity effects and mechanisms of Cordyceps militaris.

Vitamin D Status and Factors Associated with Vitamin D Deficiency during the First Year of Life in Preterm Infants.

We aimed to investigate the changes in vitamin D levels and factors associated with vitamin D deficiency (VDD) during the first year of life in Korean preterm infants. We enrolled 333 preterm infants who were born at Kyungpook National University Children's Hospital between March 2013 and December 2019. 25-hydroxyvitamin D (25-OHD) levels and medical records were collected at birth, 6 months, and 12 months of age. The mean gestational age was 33.4 ± 2.3 weeks and mean 25-OHD levels at birth were 18.2 ± 13.5 ng/mL. The incidence of VDD was 82.8%, 30.6%, and 27.0% at birth, 6 months, and 12 months, respectively. The incidence of severe VDD (25-OHD < 10 ng/mL) was 31.5%, 1.5%, and 0%, at birth, 6 months, and 12 months, respectively. Among infants with severe VDD, the deficiency persisted in 49.6% at 6 months, and 35.3% at 12 months. The strongest predictor of VDD during follow-up was 25-OHD concentration at birth. Vitamin D supplementation at 400 IU/day did not affect vitamin D levels during the first year of life. Therefore, it is important to prevent neonatal VDD through maternal vitamin D supplementation during pregnancy. Further research is needed to determine the optimal vitamin D supplementation dose for Korean preterm infants.

Effects of Cognitive Behavioral Group Program for Mental Health Promotion of University Students.

This study aimed to explore the effects of a group cognitive behavioral program on depression, self-esteem, and interpersonal relations among undergraduate students. A non-equivalent control group pretest-posttest design was used. A convenient sample of 37 undergraduates (18 in the experimental group and 19 in the control group) at K university located in Changwon, South Korea was used. Data were collected from February 4, 2019 to June 18, 2019. The experimental group received eight sessions of the program, which were scheduled twice a week, with each session lasting 90 min. Collected data were analyzed using a chi-square test, Fisher's exact test, independent t-test, and repeated measures ANOVA by SPSS/WIN 23.0 (SPSS, Inc., Chicago, IL, USA). The interaction of group and time was significant, indicating that the experimental group showed an improvement in depression, self-esteem, and personal relationship compared to the control group. A significant group by time interaction for depression, self-esteem, and personal relationship was also found between the two groups. The study results revealed that the group cognitive behavioral program was effective in reducing depression and improving self-esteem and interpersonal relation. Therefore, the group cognitive behavioral program can be used for promoting the mental health of students as well as for preventing depression in a university setting.

A Deep Learning-Based Approach for Identifying the Medicinal Uses of Plant-Derived Natural Compounds.

Medicinal plants and their extracts have been used as important sources for drug discovery. In particular, plant-derived natural compounds, including phytochemicals, antioxidants, vitamins, and minerals, are gaining attention as they promote health and prevent disease. Although several in vitro methods have been developed to confirm the biological activities of natural compounds, there is still considerable room to reduce time and cost. To overcome these limitations, several in silico methods have been proposed for conducting large-scale analysis, but they are still limited in terms of dealing with incomplete and heterogeneous natural compound data. Here, we propose a deep learning-based approach to identify the medicinal uses of natural compounds by exploiting massive and heterogeneous drug and natural compound data. The rationale behind this approach is that deep learning can effectively utilize heterogeneous features to alleviate incomplete information. Based on latent knowledge, molecular interactions, and chemical property features, we generated 686 dimensional features for 4,507 natural compounds and 2,882 approved and investigational drugs. The deep learning model was trained using the generated features and verified drug indication information. When the features of natural compounds were applied as input to the trained model, potential efficacies were successfully predicted with high accuracy, sensitivity, and specificity.

Preventive Effects of Vitamin C on Diethylnitrosamine-induced Hepatotoxicity in Smp30 Knockout Mice.

Vitamin C (L-ascorbic acid) is well known as a free radical scavenger that protects cells against damage from oxidative stress. Herein, we investigated the effects of vitamin C against diethylnitrosamine (DEN)-induced hepatotoxicity. Male wild-type (C57BL/6) and senescence marker protein-30 (Smp30) knockout (KO) mice were used and divided in the following four groups: WT group (n=15): Wild-type (WT) mice fed vitamin C-free diet with tap water; WV group (n=14): WT mice fed vitamin C-free diet with water supplemented with 1.5 g/kg vitamin C; KT group (n=12): Smp30 KO mice fed vitamin C-free diet with tap water; and KV group (n=13): Smp30 KO mice fed vitamin C-free diet with water supplemented with 1.5 g/kg vitamin C. A single intraperitoneal injection of DEN (5 mg/kg body weight) was injected in the second week during the experimental period. Mice were sacrificed after 17 weeks of treatment to investigate the effect of dietary vitamin C on DEN-induced hepatotoxicity. The results showed that vitamin C significantly increased the mean lifespan (p<0.05) in the WT, WV and KV groups compared with the KT group. The serum concentrations of γ-glutamyl transpeptidase, alanine aminotransferase, and aspartate aminotransferase did not significantly differ among groups. The WT group exhibited significantly more acute cellular swelling accompanied by centrilobular necrosis, focal lymphocyte infiltration, and eosinophilic intracytoplasmic inclusion bodies as compared with the WV and KV groups, suggesting that vitamin C had a hepatoprotective effect. Dysplastic, large, and binucleated hepatocytes were also observed in the WT group, but these pathological signs were absent from the WV and KV groups. Our experimental evidence suggests that vitamin C supplementation in Smp30 KO mice was effective for the treatment of DEN-induced hepatotoxicity.

Inhibition of Formation of Azoxymethane-induced Colonic Aberrant Crypt Foci in Rats by Edible Green Algae Capsosiphon fulvescens and Brown Algae Hizikia fusiforme.

Capsosiphon fulvescens (green seaweed) and Hizikia fusiforme (brown seaweed) are marine algae consumed as food supplements, especially in Japan, China and Korea, and are considered traditional medicinal tonics for certain ailments. The aim of this study was to investigate the possible inhibitory effects of dietary C. fulvescens and H. fusiforme on azoxymethane (AOM)-induced colorectal cancer (CRC) in rats. F344 male rats (5 weeks, 150 g) were divided into six groups as follows. Group 1: Injected with normal saline solution and fed control diet (untreated control). Group 2: Injected with AOM and fed control diet (treated control). Group 3: Injected with AOM and fed 1% C. fulvescens diet. Group 4: Injected with AOM and fed 2% C. fulvescens diet. Group 5: Injected with AOM and fed 2% H. fusiforme diet. Group 6: Injected with AOM and fed 6% H. fusiforme diet. Test animals received subcutaneous injections of AOM (15 mg/1 ml/kg body weight) once a week for 2 weeks to induce aberrant crypt foci (ACF) in treated control and experimental groups. We evaluated the effects of dietary C. fulvescens and H. fusiforme at two different dose levels: 1 and 2% C. fulvescens, and 2 and 6% H. fusiforme, on colonic carcinogenesis by AOM in rats. Our results suggest that body weights were not significantly different amongst groups. We found that feeding C. fulvescens and H. fusiforme with a control diet significantly (p<0.05) inhibited the development of ACF in experimental groups. C. fulvescens and H. fusiforme in food also significantly (p<0.05) reduced the proliferating cell nuclear antigen labeling index in the colonic tissues of experimental groups. These results demonstrate the chemopreventive potential of C. fulvescens and H. fusiforme against CRC in an AOM-induced rats.

Cohort profile: the National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS) in Korea.

PURPOSE: The National Health Insurance Service-Health Screening Cohort (NHIS-HEALS) is a cohort of participants who participated in health screening programmes provided by the NHIS in the Republic of Korea. The NHIS constructed the NHIS-HEALS cohort database in 2015. The purpose of this cohort is to offer relevant and useful data for health researchers, especially in the field of non-communicable diseases and health risk factors, and policy-maker. PARTICIPANTS: To construct the NHIS-HEALS database, a sample cohort was first selected from the 2002 and 2003 health screening participants, who were aged between 40 and 79 in 2002 and followed up through 2013. This cohort included 514 866 health screening participants who comprised a random selection of 10% of all health screening participants in 2002 and 2003. FINDINGS TO DATE: The age-standardised prevalence of anaemia, diabetes mellitus, hypertension, obesity, hypercholesterolaemia and abnormal urine protein were 9.8%, 8.2%, 35.6%, 2.7%, 14.2% and 2.0%, respectively. The age-standardised mortality rate for the first 2 years (through 2004) was 442.0 per 100 000 person-years, while the rate for 10 years (through 2012) was 865.9 per 100 000 person-years. The most common cause of death was malignant neoplasm in both sexes (364.1 per 100 000 person-years for men, 128.3 per 100 000 person-years for women). FUTURE PLANS: This database can be used to study the risk factors of non-communicable diseases and dental health problems, which are important health issues that have not yet been fully investigated. The cohort will be maintained and continuously updated by the NHIS.

Melatonin ameliorates alcohol-induced bile acid synthesis by enhancing miR-497 expression.

Alcoholic liver disease is a major cause of chronic liver disease worldwide, and cannabinoid receptor type 1 (CB1R) is involved in a diverse metabolic diseases. B-cell translocation gene 2 (BTG2) and yin yang 1 (YY1) are a potent regulator of biological conditions. Melatonin plays a crucial role in regulating diverse physiological functions and metabolic homeostasis. MicroRNAs are key regulators of various biological processes. Herein, we demonstrate that melatonin improves bile acid synthesis in the liver of alcohol-fed mice by controlling miR-497 expression. The level of bile acid and the expression of Cb1r, Btg2, Yy1, and bile acid synthetic enzymes were significantly elevated in the livers of Lieber-DeCarli alcohol-fed mice. The overexpression of Btg2 enhanced Yy1 gene expression and bile acid production, whereas disrupting the CB1R-BTG2-YY1 cascade protected against the bile acid synthesis caused by alcohol challenge. We identified an alcohol-mediated YY1 binding site on the cholesterol 7α-hydroxylase (Cyp7a1) gene promoter using promoter deletion analysis and chromatin immunoprecipitation assays. Notably, melatonin attenuated the alcohol-stimulated induction of Btg2, Yy1 mRNA levels and bile acid production by promoting miR-497. Overexpression of a miR-497 mimic dramatically diminished the increase of Btg2 and Yy1 gene expression as well as bile acid production by alcohol, whereas this phenomenon was reversed by miR-497 inhibitor. These results demonstrate that the upregulation of miR-497 by melatonin represses alcohol-induced bile acid synthesis by attenuating the BTG2-YY1 signaling pathway. The melatonin-miR497 signaling network may provide novel therapeutic targets for the treatment of hepatic metabolic dysfunction caused by the alcohol-dependent pathway.

ENA-A actimineral resource A extends lifespan associated with antioxidant mechanism in SMP30 knockout mice.

ENA-actimineral resource A (ENA-A) is an alkaline mineral water and has a few biological activities such as antioxidant activity. The aim of this study was to examine the effects of ENA-A on lifespan in mice using senescence marker protein-30 knockout mice. The present study had groups of 18-week-old mice (n = 24), 26-week-old mice (n = 12), and 46-week-old mice (n = 20). Each differently aged mice group was divided into three subgroups: a control group, a 5 % ENA-A-treated group, and a 10 % ENA-A-treated group. Mice in the 18-week-old group were treated with vitamin C drinking water 1.5 g/L. However, the mice in the 26-week-old and 46-week-old groups were not treated with vitamin C. The experiments were done for 18 weeks. All vitamin C-treated mice were alive at week 18 (100% survival rate). In the non-vitamin C group, the 10% ENA-A-treated mice were alive at week 18. The control and 5% ENA-A-treated mice died by week 15. As expected, vitamin C was not detected in the non-vitamin C-treated group. However, vitamin C levels were increased in an ENA-A dose-dependent manner in the vitamin C-treated group. In the TUNEL assay, a number of positive hepatocytes significantly decreased in an ENA-A dose-dependent manner. Periodic acid Schiff positive hepatocytes were significantly increased in an ENA-A dose-dependent manner. In addition, the expression level of CuZnSOD was increased by the ENA-A treatment. These data suggest that the intake of ENA-A has a critical role in the anti-aging mechanism and could be applied toward the lifespans of humans.

Prevention of inflammation-mediated neurotoxicity by butylidenephthalide and its role in microglial activation.

Microglial cells are the prime effectors in immune and inflammatory responses of the central nervous system (CNS). During pathological conditions, the activation of these cells helps restore CNS homeostasis. However, chronic microglial activation endangers neuronal survival through the release of various proinflammatory molecules and neurotoxins. Thus, negative regulators of microglial activation have been considered as potential therapeutic candidates to target neurodegeneration, such as that in Alzheimer's and Parkinson's diseases. The rhizome of Ligusticum chuanxiong Hort. (Ligusticum wallichii Franch) has been widely used for the treatment of vascular diseases in traditional oriental medicine. Butylidenephthalide (BP), a major bioactive component from L. chuanxiong, has been reported to have a variety of pharmacological activities, including vasorelaxant, anti-anginal, anti-platelet and anti-cancer effects. The aim of this study was to examine whether BP represses microglial activation. In rat brain microglia, BP significantly inhibited the lipopolysaccharide (LPS)-induced production of nitric oxide (NO), tumour necrosis factor-α and interleukin-1ß. In organotypic hippocampal slice cultures, BP clearly blocked the effect of LPS on hippocampal cell death and inhibited LPS-induced NO production in culture medium. These results newly suggest that BP provide neuroprotection by reducing the release of various proinflammatory molecules from activated microglia.

Paeonol attenuates inflammation-mediated neurotoxicity and microglial activation.

Chronic activation of microglial cells endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. The root of Paeonia lactiflora Pall has been considered useful for the treatment of various disorders in traditional oriental medicine. Paeonol, found in the root of Paeonia lactiflora Pall, has a wide range of pharmacological functions, including anti-oxidative, anti-inflammatory and neuroprotective activities. The objective of this study was to examine the efficacy of paeonol in the repression of inflammation-induced neurotoxicity and microglial cell activation. Organotypic hippocampal slice cultures and primary microglial cells from rat brain were stimulated with bacterial lipopolysaccharide. Paeonol pretreatment was performed for 30 minutes prior to lipopolysaccharide addition. Cell viability and nitrite (the production of nitric oxide), tumor necrosis factor-alpha and interleukin-1beta products were measured after lipopolysaccharide treatment. In organotypic hippocampal slice cultures, paeonol blocked lipopolysaccharide-related hippocampal cell death and inhibited the release of nitrite and interleukin-1beta. Paeonol was effective in inhibiting nitric oxide release from primary microglial cells. It also reduced the lipopolysaccharide-stimulated release of tumor necrosis factor-alpha and interleukin-1ß from microglial cells. Paeonol possesses neuroprotective activity in a model of inflammation-induced neurotoxicity and reduces the release of neurotoxic and proinflammatory factors in activated microglial cells.

Neuroprotective effects of INM-176 against lipopolysaccharide-induced neuronal injury.

Neuroinflammation plays a critical role in the etiology of chronic neurodegenerative diseases such as Alzheimer's disease. INM-176 is a standardized ethanolic extract of Angelica gigas, which has been traditionally used as a tonic to treat anemia. In the present study, we investigated whether INM-176 exhibits neuroprotective activities against lipopolysaccharide (LPS)-induced neuronal damage in vitro and in vivo. In primary microglial cells, INM-176 significantly inhibited LPS-induced nitric oxide release and expression of tumor necrosis factor-α and interleukin-1ß. The expression levels of inducible nitric oxide synthase and cylcooxygenase-2 in BV2 microglial cells were markedly upregulated by LPS, but this increased expression was counteracted by INM-176. LPS-mediated neuronal damage in an organotypic hippocampal slice culture was also attenuated by the administration of INM-176. In addition, LPS (1 µg/2 µl, i.c.v.)-induced cognitive dysfunction in mice, as determined by passive avoidance and Y-maze tasks, was significantly attenuated by the administration of INM-176. Furthermore, the activation of microglia or astrocytes by LPS in the hippocampal regions of mice was suppressed by INM-176. These results suggest that the neuroprotective and cognition ameliorating effects of INM-176 against LPS-induced damage are mediated, in part, by its anti-inflammatory activities.

Effects of green tea ingestion on postprandial drops in blood pressure in older adults.

The purpose of this study was to examine whether drinking green tea can prevent postprandial drops in blood pressure in older adults. Participants included 29 older adults who had experienced postprandial drops in systolic blood pressure of more than 15 mmHg in a previous study. During the experimental phase, each participant drank 400 mL of green tea before lunch; during the control phase, participants ate lunch without any tea. Blood pressure and heart rate were measured during both phases before lunch and at 15-minute intervals for 90 minutes after lunch. Drinking green tea before lunch elicited significant pressor effects by increasing systolic and diastolic blood pressure an average of 15.1 mmHg and 5.7 mmHg, respectively. It had no significant effect on heart rate. Drinking green tea before meals is recommended for older adults who experience postprandial hypotension; however, the appropriate volume and time of green tea ingestion to prevent a postprandial drop in blood pressure should be further studied.

Gami-Chunghyuldan ameliorates memory impairment and neurodegeneration induced by intrahippocampal Aß 1-42 oligomer injection.

Soluble oligomeric forms of amyloid beta (AßO) are regarded as a main cause of synaptic and cognitive dysfunction in Alzheimer's disease (AD) and have been a primary target in the development of drug treatments for AD. The present study utilized a mouse model of AD induced by intrahippocampal injection of AßO (10 µM) to investigate the effects of Gami-Chunghyuldan (GCD), a standardized multi-herbal medicinal formula, on the presentation of memory deficits and neurohistological pathogenesis. GCD (10 and 50mg/kg/day, 5 days, p.o.) improved AßO-induced memory impairment as well as reduced neuronal cell death, astrogliosis, and microgliosis in the hippocampus. In addition, GCD prevented AßO-triggered synaptic disruption and cholinergic fiber loss. These results suggest that GCD may be useful in the prevention and treatment of AD.

Anti-inflammatory effects of crocin and crocetin in rat brain microglial cells.

Microglial cells play critical roles in the immune and inflammatory responses of the central nervous system (CNS). Under pathological conditions, the activation of microglia helps in restoring CNS homeostasis. However, chronic microglial activation endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. Thus, negative regulators of microglial activation have been considered as potential therapeutic candidates to target neurodegeneration, such as that observed in Alzheimer's and Parkinson's diseases. Crocin and crocetin, found in the fruits of gardenia and in the stigmas of saffron, have been considered for the treatment of various disorders in traditional oriental medicine. Crocin and crocetin have been reported to have diverse pharmacological functions, such as anti-hyperlipidemic, anti-atherosclerotic, and anti-cancer effects. Specifically, the neuroprotective potential of crocetin derivatives has previously been demonstrated. The specific aim of this study was to examine whether crocin or crocetin represses microglial activation. Crocin and crocetin were shown to be effective in the inhibition of LPS-induced nitric oxide (NO) release from cultured rat brain microglial cells. These compounds reduced the LPS-stimulated productions of tumor necrosis factor-α, interleukin-1ß, and intracellular reactive oxygen species. The compounds also effectively reduced LPS-elicited NF-κB activation. In addition, crocin reduced NO release from microglia stimulated with interferon-γ and amyloid-ß. In organotypic hippocampal slice cultures, both crocin and crocetin blocked the effect of LPS on hippocampal cell death. These results suggest that crocin and crocetin provide neuroprotection by reducing the production of various neurotoxic molecules from activated microglia.

Protective effects of Chunghyuldan against ROS-mediated neuronal cell death in models of Parkinson's disease.

Previous reports have suggested that the herbal medicine Chunghyuldan (CHD, Qingxue-dan in Chinese and Daio-Orengedokuto in Japanese) has wide-ranging biological effects, including anti-hyperlipidaemic, anti-ischaemic, anti-inflammatory and antioxidant activities. Reactive oxygen species (ROS)-mediated mitochondrial dysfunction is thought to be one of the major pathological mechanisms responsible for Parkinson's disease (PD) and may underlie the selective loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) that is a hallmark of this disease. In this study, we examined the neuroprotective effects of CHD in PD models produced by treatment with neurotoxins that act via ROS-mediated mitochondrial dysfunction. In an in vitro PD model using 6-hydroxydopamine, CHD applied at concentrations of 10 and 100 µg/ml exhibited significant protective effects in PC12 cells by inhibiting intracellular ROS generation. CHD applied at 10 and 100 µg/ml also prevented 6-hydroxydopamine-induced mitochondrial depolarization and elevation of caspase-3 activity. At the same doses, CHD showed regulatory effects on the haem oxygenase-1 and gp91 phagocytic oxidase which have critical roles in generating ROS. In addition, CHD protected dopaminergic neurons in a primary mesencephalic culture against MPP+ neurotoxicity. In an in vivo PD model produced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine treatment (20 mg/kg, 4 times, i.p.), co-administration of CHD (50 mg/kg, 5 days, p.o.) ameliorated PD-like behavioural symptoms (bradykinesia) and reduced dopaminergic neuronal damage in the SNpc and striatum as measured by immunocytochemistry. These results demonstrate the neuroprotective effects of CHD in PD models that are mediated through inhibition of ROS generation and associated mitochondrial dysfunction.

Inhibitory effects of 5-chloroacetyl-2-piperidino-1,3-selenazole, a novel selenium-containing compound, on skin melanin biosynthesis.

OBJECTIVES: Increased production and accumulation of melanin leads to many hyperpigmentation disorders such as melasma, freckles and geriatric pigment spots. Thus, there is a need for the development of depigmenting agents. Based on our previous reports, selenium derivatives as anti-melanogenic lead compounds could be very important. The aim of this study was to investigate the depigmenting effect of novel selenium-containing compounds. METHODS: The inhibitory effects of 5-chloroacetyl-2-piperidino-1,3-selenazole (CS1), a novel selenium-containing compound, on melanogenesis were investigated in B16F10 melanoma cells and cultured brownish guinea pig skin tissue with alpha-melanocyte-stimulating hormone stimulation. KEY FINDINGS: We found that CS1 inhibited melanin production in B16F10 cells by suppressing tyrosinase activity and its protein expression. In addition, Western blotting analysis revealed that CS1 suppressed the expression of tyrosinase-related protein (TRP)-1 and TRP-2. Therefore, the depigmenting effect of CS1 might have been due to inhibition of tyrosinase activity and expression of melanogenic enzymes. Furthermore, CS1 had inhibitory effects on melanin biosynthesis of primary cultured skin of brownish guinea pig. CONCLUSIONS: The results suggested that CS1 could be a useful candidate for the treatment of skin hyperpigmentation.

Genipin inhibits the inflammatory response of rat brain microglial cells.

Microglia are the prime effectors in immune and inflammatory responses of the central nervous system (CNS). Under pathological conditions, the activation of these cells helps restore CNS homeostasis. However, chronic microglial activation endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. Thus, negative regulators of microglial activation have been considered as potential therapeutic candidates to target neurodegeneration, such as that in Alzheimer's and Parkinson's diseases. Genipin, the aglycon of geniposide found in gardenia fruit has long been considered for treatment of various disorders in traditional oriental medicine. Genipin has recently been reported to have diverse pharmacological functions, such as antimicrobial, antitumor, and anti-inflammatory effects. The specific aim of this study was to examine whether genipin represses brain microglial activation. Genipin was effective at inhibiting LPS-induced nitric oxide (NO) release from cultured rat brain microglial cells. Genipin reduced the LPS-stimulated production of tumor necrosis factor-alpha, interleukin-1beta, prostaglandin E(2), intracellular reactive oxygen species, and NF-kappaB activation. In addition, genipin reduced NO release from microglia stimulated with interferon-gamma and amyloid-beta. Both pretreatment and post-treatment of genipin to LPS-stimulated microglia were effective at decreasing NO release. Furthermore, genipin effectively inhibited microglial activation in a mouse model of brain inflammation. These results suggest that genipin provide neuroprotection by reducing the production of various neurotoxic molecules from activated microglia.