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Background: Mitochondrial dysfunction is strongly associated with several kidney diseases. However, no studies have evaluated the potential renal hazards of serum mitochondria-inhibiting substance (MIS) and aryl hydrocarbon receptor ligand (AhRL) levels.Methods: We used serum level of MIS and AhRL and clinical renal outcomes from 1,511 participants of a prospective community-based cohort in Ansung. MIS was evaluated based on intracellular adenosine triphosphate (MIS-ATP) or reactive oxygen species (MIS-ROS) generation measured using cell-based assays.Results: During a mean 6.9-year follow-up, 84 participants (5.6%) developed a rapid decline in kidney function. In the lowest quartile group of MIS-ATP, patients were older and had metabolically deleterious parameters. In multivariate logistic regression analysis, higher MIS-ATP was associated with decreased odds for rapid decline: the odds ratio (OR) of 1% increase was 0.977 (95% confidence interval [CI], 0.957 to 0.998; P=0.031), while higher MIS-ROS was marginally associated with increased odds for rapid decline (OR, 1.014; 95% CI, 0.999 to 1.028; P=0.055). However, serum AhRL was not associated with the rapid decline in kidney function. In subgroup analysis, the renal hazard of MIS was particularly evident in people with hypertension and low baseline kidney function.Conclusion: Serum MIS was independently associated with a rapid decline in kidney function, while serum AhRL was not. The clinical implication of renal hazard on serum MIS requires further evaluation in future studies.

Parkinson’s disease (PD), characterized by degeneration of dopaminergic neurons, share pathogenic features with obesity, including mitochondrial dysfunction and oxidative stress. Paraoxonase 2 (PON2) is an inner mitochondrial membrane protein that is highly expressed in dopaminergic neurons and is involved in the regulation of mitochondrial oxidative stress. However, no drug targeting PON2 has ever been developed for the treatment of PD. Here, we show that vutiglabridin, a clinical phase 2-stage drug for the treatment of obesity, has therapeutic effects in PD models, targeting mitochondrial PON2. Vutiglabridin penetrates into the brain, binds to PON2, and restores 1-methyl-4-phenylpyridinium (MPP+)-induced mitochondrial dysfunction in SH-SY5Y neuroblastoma cells. Knockdown of PON2 by lentiviral shRNA infection abolished the effects of vutiglabridin on mitochondria. In mice, vutiglabridin significantly alleviated motor impairments and damage to dopaminergic neurons in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD model, and these effects were also abolished in PON2-knockdown mice, suggesting that vutiglabridin is neuroprotective via PON2. Extensive in vitro and in vivo assessment of potential neurotoxicity showed vutiglabridin to be safe. Overall, these findings provide support for the clinical development of vutiglabridin as a novel PON2 modulator for the treatment of PD.One Sentence SummaryTargeting paraoxonase-2 by a clinical-stage compound vutiglabridin provides neuroprotective effects in preclinical models of Parkinson’s disease.

The early prediction and identification of risk factors for diabetes may prevent or delay diabetes progression. In this study, we developed an interactive online application that provides the predictive probabilities of prediabetes and diabetes in 4 years based on a Bayesian network (BN) classifier, which is an interpretable machine learning technique. The BN was trained using a dataset from the Ansung cohort of the Korean Genome and Epidemiological Study (KoGES) in 2008, with a follow-up in 2012. The dataset contained not only traditional risk factors (current diabetes status, sex, age, etc.) for future diabetes, but it also contained serum biomarkers, which quantified the individual level of exposure to environment-polluting chemicals (EPC). Based on accuracy and the area under the curve (AUC), a tree-augmented BN with 11 variables derived from feature selection was used as our prediction model. The online application that implemented our BN prediction system provided a tool that performs customized diabetes prediction and allows users to simulate the effects of controlling risk factors for the future development of diabetes. The prediction results of our method demonstrated that the EPC biomarkers had interactive effects on diabetes progression and that the use of the EPC biomarkers contributed to a substantial improvement in prediction performance.

Background: High circulating levels of dioxins and dioxin-like chemicals, acting via the aryl hydrocarbon receptor (AhR), have previously been linked to diabetes. We now investigated whether the serum AhR ligands (AhRL) were higher in subjects with metabolic syndrome (MetS) and in subjects who had developed a worsened glucose tolerance over time.Methods: Serum AhRL at baseline was measured by a cell-based AhRL activity assay in 70-year-old subjects (n=911) in the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study. The main outcome measures were prevalent MetS and worsening of glucose tolerance over 5 years of follow-up.Results: AhRL was significantly elevated in subjects with prevalent MetS as compared to those without MetS, following adjustment for sex, smoking, exercise habits, alcohol intake and educational level (P=0.009). AhRL at baseline was higher in subjects who developed impaired fasting glucose or diabetes at age 75 years than in those who remained normoglycemic (P=0.0081). The odds ratio (OR) of AhRL for worsening glucose tolerance over 5 years was 1.43 (95% confidence interval [CI], 1.13 to 1.81; P=0.003, continuous variables) and 2.81 (95% CI, 1.31 to 6.02; P=0.008, in the highest quartile) adjusted for sex, life style factors, body mass index, and glucose.Conclusion: These findings support a large body of epidemiologic evidence that exposure to AhR transactivating substances, such as dioxins and dioxin-like chemicals, might be involved in the pathogenesis of MetS and diabetes development. Measurement of serum AhRL in humans can be a useful tool in predicting the onset of metabolic disorders.

Parkinson's disease (PD) is a multifactorial neurodegenerative disease manifesting mitochondrial damages and neuroinflammation. Qi is defined as a natural power that can regulate the energy flow in Oriental medicine, whereas mitochondria generate energy power in Western medicine. We investigated whether Qi-enhancing component in Oriental herb medicines could activate mitochondrial activities. Quercetin was found as a major bioactive compound in most Qi-activating Oriental herb medicines through online search for active compounds in several Oriental Medicine databases. We then investigated if quercetin could reverse 1-methyl-4-phenylpyridinium (MPP+)-induced mitochondrial dysfunction and lipopolysaccharide (LPS)-induced neuroinflammation. Mitochondrial activities were monitored based on complex 1 NADH dehydrogenase activities, ATP contents, mitochondrial membrane potential, cellular/mitochondrial reactive oxygen species, and oxygen consumption rate in SH-SY5Y cells. Quercetin at concentration up to 20 µg/ml was not cytotoxic to SH-SY5Y cells. Pre-treatment with quercetin significantly protected mitochondrial damages in 1 mM MPP+- or 100 ng/ml LPS-treated cells. Quercetin increased expression levels of tyrosine hydroxylase and mitochondria controlling proteins. When in vivo effects of quercetin were assessed by immunohistochemical staining of tissue sections from LPS-injected mice brains, quercetin reduced the activation of microglia and astrocytes in the hippocampus and substantia nigra of LPS-injected mice. Our data suggest that Qi-activating quercetin might be therapeutically effective for neuroinflammation-mediated neurodegeneration by alleviating mitochondrial damages.

Purpose Elevated aryl hydrocarbon receptor (AhR) transactivating (AHRT) activity and uremia in chronic kidney disease (CKD) may interact with each other, further complicating the disease course. In this study, we prospectively estimated serum AHRT activity using a highly sensitive cell-based AhR-dependent luciferase activity assay in CKD patients and compared differences therein according to treatment modality. Materials and methods Patients undergoing peritoneal dialysis (PD) (n=22) and hemodialysis (HD) (n=38) and patients with pre-dialysis CKD stage IV or V (n=28) were included. AHRT activity and intracellular adenosine triphosphate (ATP) levels were measured. We performed a correlation analysis for AHRT activity, ATP levels, and various clinical parameters. Results AHRT activity and intracellular ATP levels were inversely correlated and differed according to treatment modalities. AHRT activity was higher in non-dialysis CKD patients than in patients undergoing dialysis and was higher in patients undergoing HD, compared to PD. AHRT activity decreased after HD treatment in HD patients. ATP levels were higher in healthy controls than in patients with pre-dialysis CKD and PD and were further decreased in patients with HD. We noted significant correlations between multiple clinical parameters associated with cardiovascular risk factors and AHRT activity. Conclusion AHRT activity was elevated in CKD patients, while dialysis treatment reduced AHRT activity. Further studies are warranted to specify AHRT activity and to evaluate the precise roles thereof in patients with CKD.

In our previous study, 20 nm-sized amorphous silica nanoparticles (20-SiNPs), but not 50 nm-sized amorphous silica nanoparticles (50-SiNPs), induced pulmonary inflammatory response in rats exposed repeatedly for 14 days (12.5, 25, and 50 μg/time, total six times). In this study, we tried to clarify the causes of different responses induced by both SiNPs using mice (12.5, 25, and 50 μg/lung) and mouse alveolar macrophage cells. When exposed to alveolar macrophage cells for 24 h, both SiNPs decreased cell viability and enhanced ROS generation compared to controls. The 20- and 50-SiNPs also formed giant and autophagosome-like vacuoles in the cytoplasm, respectively. Structural damage of organelles was more pronounced in 20-SiNPs-treated cells than in 50-SiNPs-treated cells, and an increased mitochondrial membrane potential and mitochondrial calcium accumulation were observed only in the 20-SiNPs-treated cells. Additionally, a single intratracheal instillation of both sizes of SiNPs to mice clearly elevated the relative proportion of neutrophils and inhibited differentiation of macrophages and expression of an adhesion molecule. Meanwhile, interestingly, the total number of pulmonary cells and the levels of pro-inflammatory mediators more notably increased in the lungs of mice exposed to 20-SiNPs compared to 50-SiNPs. Given that accumulation of giant vacuoles and dilation of the ER and mitochondria are key indicators of paraptosis, we suggest that 20-SiNPs-induced pulmonary inflammation may be associated with paraptosis of alveolar macrophages.

Parkinson’s disease (PD) is a multifactorial neurodegenerative disease with damages to mitochondria and endoplasmic reticulum (ER), followed by neuroinflammation. We previously reported that a triple herbal extract DA-9805 in experimental PD toxin-models had neuroprotective effects by alleviating mitochondrial damage and oxidative stress. In the present study, we investigated whether DA-9805 could suppress ER stress and neuroinflammation in vitro and/or in vivo. Pre-treatment with DA-9805 (1 μg/ml) attenuated upregulation of glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP) and cleaved caspase-3 in SH-SY5Y neuroblastoma cells treated with thapsigargin (1 µg/ml) or tunicamycin (2 µg/ml). In addition, DA-9805 prevented the production of IL-1β, IL-6, TNF-α and nitric oxide through inhibition of NF-κB activation in BV2 microglial cells stimulated with lipopolysaccharides (LPS). Intraperitoneal injection of LPS (10 mg/kg) into mice can induce acute neuroinflammation and dopaminergic neuronal cell death. Oral administration of DA-9805 (10 or 30 mg/kg/day for 3 days before LPS injection) prevented loss of dopaminergic neurons and activation of microglia and astrocytes in the substantia nigra in LPS-injected mouse models. Taken together, these results indicate that DA-9805 can effectively prevent ER stress and neuroinflammation, suggesting that DA-9805 is a multitargeting and disease-modifying therapeutic candidate for PD.

α-Naphthoflavone (αNF) is a prototype flavone, also known as a modulator of aryl hydrocarbon receptor (AhR). In the present study, we investigated the molecular mechanisms of αNF-induced cytotoxic effects in HT22 mouse hippocampal neuronal cells. αNF induced apoptotic cell death via activation of caspase-12 and -3 and increased expression of endoplasmic reticulum (ER) stress-associated proteins, including C/EBP homologous protein (CHOP). Inhibition of ER stress by treatment with the ER stress inhibitor, salubrinal, or by CHOP siRNA transfection reduced αNF-induced cell death. αNF activated mitogen-activated protein kinases (MAPKs), such as p38, JNK, and ERK, and inhibition of MAPKs reduced αNF-induced CHOP expression and cell death. αNF also induced accumulation of reactive oxygen species (ROS) and an antioxidant, N-acetylcysteine, reduced αNF-induced MAPK phosphorylation, CHOP expression, and cell death. Furthermore, αNF activated c-Src kinase, and inhibition of c-Src by a kinase inhibitor, SU6656, or siRNA transfection reduced αNF-induced ROS accumulation, MAPK activation, CHOP expression, and cell death. Inhibition of AhR by an AhR antagonist, CH223191, and siRNA transfection of AhR and AhR nuclear translocator reduced αNF-induced AhR-responsive luciferase activity, CHOP expression, and cell death. Finally, we found that inhibition of c-Src and MAPKs reduced αNF-induced transcriptional activity of AhR. Taken together, these findings suggest that αNF induces apoptosis through ER stress via c-Src-, ROS-, MAPKs-, and AhR-dependent pathways in HT22 cells.

Persistent organic pollutants(POPs) are suggested to be potential risk factors for gestational diabetes mellitus(GDM). We examined the hypothesis that the aryl hydrocarbon receptor trans-activating(AhRT) activity, a potential biomarker for the presence of POPs, could be a GDM risk factor in pregnant women. A total of 390 GDM and 100 normal pregnant(non-GDM) subjects in the Korea National Diabetes Program cohort voluntarily participated. We measured AhRT activity and concentrations of ATP and reactive oxygen in the serum collected at the screening of the participants for GDM using recombinant Hepa1c1c7 cells. Odds ratios(ORs) and 95% confidence intervals(CIs) were estimated using multivariable logistic regression models. The sensitivity and specificity of AhRT activity for GDM diagnostics were measured by receiver operating characteristic(ROC) analysis. Body mass index at pre-pregnancy and delivery and systolic blood pressure were significantly higher in the GDM group. AhRT activity was higher, and ATP concentrations were lower in the GDM group than the non-GDM group(P P 2 = 0.387) and negatively correlated with ATP production(r2 = −0.650). In the ROC curve, AhRT activity had 70.9% sensitivity and 90.0% specificity for glucose-50, a GDM screening method. In conclusion, this study suggests that serum AhRT activity is positively associated with the risk of GDM.

Hepatic hepcidin is a well-known major iron regulator and has been reported to be closely related to hepatitis C virus (HCV) replication. However, pharmacological targeting of the hepcidin in HCV replication has not been reported. A short-chain fatty acid, 4-Phenyl butyrate (4-PBA), is an acid chemical chaperone that acts as a histone deacetylase inhibitor (HDACi) to promote chromosomal histone acetylation. Here, we investigated the therapeutic effect of 4-PBA on hepcidin expression and HCV replication. We used HCV genotype 1b Huh 7.5-Con1 replicon cells and engraftment of NOD/SCID mice as in vitro and in vivo models to test the effect of 4-PBA. It was found that 4-PBA inhibited HCV replication in Huh7.5-Con1 replicon cells in a concentration- and time-dependent manner through the induction of hepcidin expression by epigenetic modification and subsequent upregulation of interferon-&alpha, signaling. HCV formed a membranous web composed of double-membrane vesicles and was utilized for RNA replication. Moreover, 4-PBA also disrupted the integrity of the membranous web and interfered with the molecular interactions critical for the assembly of the HCV replication complex. These findings suggest that 4-PBA is a key epigenetic inducer of anti-HCV hepatic hepcidin and might at least in part play a role in targeting host factors related to HCV infection as an attractive complement to current HCV therapies.

Background Persistent organic pollutants (POPs) may cause diabetes, in part through aryl hydrocarbon receptor (AhR) binding. Ensuing mitochondrial dysfunction is postulated to mediate this effect. We aim to investigate the association of POPs with incident diabetes indirectly by bio-assaying AhR ligand bioactivity and intracellular ATP level induced by participant serum samples. Methods In incident case-cohort analyses of one ELSA-Brasil center, 1605 eligible subjects without diabetes at baseline had incident diabetes ascertained by self-report, medication use, OGTT or HbA1c at follow-up 4 years later. We assayed AhR ligand bioactivity (AhRL) and intracellular ATP content, the latter reflecting the presence of mitochondria-inhibiting substances (MIS), following incubation of recombinant mouse Hepa1c1c7 cells with participant sera for 71 incident diabetes cases and 472 randomly selected controls. Results In multiply-adjusted proportional hazards regression analyses, those with above-median AhRL and below-median MIS-ATP had 69 and 226% greater risk of developing diabetes (HR = 1.69; 95%CI 1.01–2.83 and 3.26; 1.84–5.78), respectively. A strong interaction was seen between the two exposures (HRhigh AhRL/low MIS-ATP vs. low AhRL/high MIS-ATP = 8.15; 2.86–23.2). Conclusion The markedly increased incidence of diabetes seen in those with both higher AhR ligand bioactivity and increased mitochondrial inhibition supports the hypothesis that widespread POPs exposure contributes to the diabetes epidemic.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has various toxicological effects in adipose tissue. Evidence is accumulating that glabridin, a flavonoid extracted from licorice, has beneficial effects on the regulation of glucose homeostasis. In this study, we investigated whether glabridin suppresses TCDD-induced loss of adipogenic action using 3T3-L1 adipocytes as a cell culture model of wasting syndrome. Glabridin effectively suppressed TCDD-induced loss of lipid accumulation in this model. Pretreating cells with glabridin increased the gene expression of not only the adipogenesis-associated key transcription factors peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer binding protein alpha, but also lipoprotein lipase in the presence of TCDD. TCDD decreased insulin-stimulated glucose uptake, which was effectively restored by pretreatment with glabridin. Glabridin also inhibited the TCDD-driven decreased production of insulin receptor substrate 1 and glucose transporter 4. TCDD increased the production of mitochondrial superoxides, prostaglandin E2 , phospholipase A2 , cyclooxygenase-1 and intracellular calcium concentrations, while reducing the production of PPARγ coactivator 1 alpha and glycolysis. However, glabridin treatment reduced these TCDD-induced effects. We conclude that glabridin suppresses the TCDD-induced loss of lipid accumulation in 3T3-L1 adipocytes by regulating the levels of PPARγ, CCAAT/enhancer binding protein alpha, lipoprotein lipase, glucose uptake, prostaglandin E2 and energy metabolism. These results also provide in vitro evidence of the effects of glabridin on adipocyte metabolism, which suggests a protective effect against dioxin exposure in the development of insulin resistance and diabetes.

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is an environmental contaminant. Xanthohumol is a prenylated flavonoid found in hops (Humulus lupulus) and beer. The aim of the current study was to explore the role of xanthohumol in modulating the toxicity of TCDD in MC3T3-E1 osteoblastic cells. In cells treated with TCDD alone, intracellular Ca2+ concentrations, mitochondrial membrane potential disruption, reactive oxygen species production, cardiolipin peroxidation, nitric oxide release and cytochrome P450 1A1 expression were significantly increased. TCDD treatment increased the mRNA levels of extracellular signal-regulated kinase 1 and nuclear factor kappa B, and significantly decreased the level of protein kinase B (AKT) in MC3T3-E1 osteoblastic cells. However, the presence of xanthohumol alleviated the pathological effects of TCDD. In addition, xanthohumol treatment significantly increased the expression of genes associated with osteoblast differentiation (alkaline phosphatase, osteocalcin, osteoprotegerin and osterix). We conclude that xanthohumol has a beneficial influence and may antagonize TCDD toxicity in osteoblastic cells.

The environmental pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is known to affect bone metabolism. We evaluated the protective effects of the triterpene glycoside actein from the herb black cohosh against TCDD-induced toxicity in MC3T3-E1 osteoblastic cells. We found that TCDD significantly reduced cell viability and increased apoptosis and autophagy in MC3T3-E1 osteoblastic cells (P

Several environmental contaminants have been linked to the development of diabetes and increased diabetes‑associated mortality. Perfluorooctanoic acid (PFOA) is a widely used perfluoroalkane found in surfactants and lubricants, and in processing aids used in the production of polymers. Furthermore, PFOA has been detected in humans, wildlife and the environment. The present study investigated the toxic effects of PFOA on rat pancreatic β‑cell‑derived RIN‑m5F cells. Cell viability, apoptosis, reactive oxygen and nitrogen species, cytokine release and mitochondrial parameters, including membrane potential collapse, reduced adenosine triphosphate levels, cardiolipin peroxidation and cytochrome c release were assessed. PFOA significantly decreased RIN‑m5F cell viability and increased apoptosis. Exposure to PFOA increased the formation of reactive oxygen species, mitochondrial superoxide, nitric oxide and proinflammatory cytokines. Furthermore, PFOA induced mitochondrial membrane potential collapse and reduced adenosine triphosphate levels, cardiolipin peroxidation and cytochrome c release. These results indicate that PFOA is associated with the induction of apoptosis in RIN-m5F cells, and induces cytotoxicity via increased oxidative stress and mitochondrial dysfunction.

Exposure to environment-polluting chemicals (EPC) is associated with the development of diabetes. Many EPCs exert toxic effects via aryl hydrocarbon receptor (AhR) and/or mitochondrial inhibition. Here we investigated if the levels of human exposure to a mixture of EPC and/or mitochondrial inhibitors could predict the development of diabetes in a prospective study, the Korean Genome and Epidemiological Study (KoGES). We analysed AhR ligands (AhRL) and mitochondria-inhibiting substances (MIS) in serum samples (n = 1,537), collected during the 2008 Ansung KoGES survey with a 4-year-follow-up. Serum AhRL, determined by the AhR-dependent luciferase reporter assay, represents the contamination level of AhR ligand mixture in serum. Serum levels of MIS, analysed indirectly by MIS-ATP or MIS-ROS, are the serum MIS-induced mitochondria inhibiting effects on ATP content or reactive oxygen species (ROS) production in the cultured cells. Among 919 normal subjects at baseline, 7.1% developed impaired glucose tolerance (IGT) and 1.6% diabetes after 4 years. At the baseline, diabetic and IGT sera displayed higher AhRL and MIS than normal sera, which correlated with indices of insulin resistance. When the subjects were classified according to ROC cut-off values, fully adjusted relative risks of diabetes development within 4 years were 7.60 (95% CI, 4.23–13.64), 4.27 (95% CI, 2.38–7.64), and 21.11 (95% CI, 8.46–52.67) for AhRL ≥ 2.70 pM, MIS-ATP ≤ 88.1%, and both, respectively. Gender analysis revealed that male subjects with AhRL ≥ 2.70 pM or MIS-ATP ≤ 88.1% showed higher risk than female subjects. High serum levels of AhRL and/or MIS strongly predict the future development of diabetes, suggesting that the accumulation of AhR ligands and/or mitochondrial inhibitors in body may play an important role in the pathogenesis of diabetes.

This study evaluates the performance of an optical sensor and measurement system (CMA-24) which can analyze the fluctuation of dissolved oxygen and pH simultaneously. In the optical sensor system, the fluorescent materials, Rudpp and HPTS which are sensitive to dissolved oxygen and pH, respectively, are coated on the bottom of a 24-well -plate by the sol-gel technology. The detection times of the emission light of the oxygen sensor were and for the dissolved oxygen of 17% and 7.6% , respectively. On the other hand, the detection times of the pH sensor were , , and using pH 6, 7, and 8, respectively. When we determined cellular respiration levels of C2C12 myocytes with CMA-24, /pH measurement system, the ratio of the uncoupled to coupled OCR (oxygen consumption rate) was 1.41. The results mean that this CMA-24 system shows almost the same sensitiveness as the commercial system.

Ethnopharmacological relevance The root of Bupleurum falcatum L. (BF) has been used in traditional Korean and Chinese medicines for over 2000 years to treat infections, fever, and chronic liver diseases. Among the many active compounds in BF ethanol extract (BFE), saikosaponins exert pharmacological activities including anti-inflammatory effects. Activated microglial cells release a variety of pro-inflammatory substances, leading to neuronal cell death and neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. The aim of the present study was to investigate the mechanism of the anti-neuroinflammatory effects of BFE using lipopolysaccharide (LPS)-stimulated microglial cells and LPS-intraperitoneal injected C57BL/6 mice. Materials and methods Dried roots of BF were extracted with 70% ethanol (tenfold volume) on a stirring plate for 24 h at room temperature to prepare BFE. Pure saikosaponins (SB3, SB4, and SD) were prepared by solvent extraction and column chromatography fractionation. BV2 murine microglial cells were treated with BFE or saikosaponins for 4 h and stimulated with LPS. Generation of nitric oxide (NO), inflammatory cytokines, and reactive oxygen species (ROS) from activated microglial cells were monitored. The effects of BFE on NF-κB activation were determined using RT-PCR, reporter assay, and immunostaining. The in vivo effects of BFE were also assessed by immunohistochemical staining of tissue sections from LPS-injected mouse brains. Results Treatment with BFE or saikosaponins dose-dependently attenuated LPS-induced production of NO, iNOS mRNA, and ROS by 30–50%. They reduced LPS-mediated increases in the mRNA levels of IL-6, IL-1β, and TNF-α by approximately 30–70% without affecting cell viability, and decreased LPS-mediated NF-κB activity via reducing p65/RELA mRNA, transcriptional activity, and nuclear localization of NF-κB. BFE also reduced LPS-induced activation of microglia and astrocytes in the hippocampus and substantia nigra of LPS-injected mice. Conclusion Our data suggest that BFE may be effective for reducing neuroinflammation-mediated neurodegeneration through suppressing NF-κB-mediated inflammatory pathways.

This paper describes a multi-well-based (24-well) electrochemical dissolved oxygen sensor (m-well ECDO sensor) array on a glass substrate, using Nafion as a solid polymer electrolyte. The designed m- well ECDO sensor array shares working electrodes, reference electrodes, and counter electrodes, to reduce the number of electrode pads to approximately one-fourth of its expected pad numbers (72 to 18), compared to the simply repeated 24 sensors. This m-well ECDO sensor array can simultaneously measure up to six sensors at individual crossing points of the row and column electrodes. The fabricated m-well ECDO sensor array showed good repeatability during five consecutive measurements at intervals of 100 s with a 2.4 μm thick Nafion membrane. The response time was about 10 s when the solution state changed from the air-saturated state to the zero-oxygen state, and the measured output current was about -1 μA and-20 nA in the corresponding states, respectively. The fabricated m-well ECDO sensor array was applied to measure the oxygen consumption rate of C2C12 cells for a cell metabolic study. The ratios of the uncoupled oxygen consumption rate (OCR) to the coupled OCR obtained from three sensors of the fabricated m-well ECDO sensor array were 2.16, 2.22, 2.18, which are higher than 1.71, 1.68, 1.73 obtained from of the XF-24 of Agilent Inc. in 5,000, 10,000, 30,000 cells, respectively. This indicates that using the fabricated m-well ECDO sensor array, variations in DO (dissolved oxygen) concentration due to cellular respiration can be effectively detected, even at low cell numbers.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has various toxicological effects in adipose tissue. Evidence is accumulating that glabridin, a flavonoid extracted from licorice, has beneficial effects on the regulation of glucose homeostasis. In this study, we investigated whether glabridin suppresses TCDD-induced loss of adipogenic action using 3T3-L1 adipocytes as a cell culture model of wasting syndrome. Glabridin effectively suppressed TCDD-induced loss of lipid accumulation in this model. Pretreating cells with glabridin increased the gene expression of not only the adipogenesis-associated key transcription factors peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer binding protein alpha, but also lipoprotein lipase in the presence of TCDD. TCDD decreased insulin-stimulated glucose uptake, which was effectively restored by pretreatment with glabridin. Glabridin also inhibited the TCDD-driven decreased production of insulin receptor substrate 1 and glucose transporter 4. TCDD increased the production of mitochondrial superoxides, prostaglandin E

Moutan cortex, Angelica Dahurica root, and Bupleurum root are traditional herbal medicines used in Asian countries to treat various diseases caused by oxidative stress or inflammation. Parkinson’s disease (PD) has been associated with mitochondrial dysfunction, but no effective treatment for mitochondrial dysfunction has yet been identified. In this study we investigated the neuroprotective effects of the triple herbal extract DA-9805 in experimental models of PD. DA-9805 was prepared by extracting three dried plant materials (Moutan cortex, Angelica Dahurica root, and Bupleurum root in a 1:1:1 mixture) with 90% ethanol on a stirring plate for 24 h at room temperature and fingerprinted using high-performance liquid chromatography. 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and its active metabolite 1-methyl-4-phenylpyridinium (MPP+), which both exert neurotoxic effects on dopaminergic neurons by inhibiting mitochondrial oxidative phosphorylation (OXPHOS) complex I, were used to make experimental models of PD. In MPP+-treated SH-SY5Y cells, DA-9805 ameliorated the suppression of tyrosine hydroxylase expression and mitochondrial damage on OXPHOS complex 1 activity, mitochondrial membrane potential, reactive oxygen species (ROS) generation, and oxygen consumption rate. In the MPTP-induced subacute PD model mice, oral administration of DA-9805 recovered dopamine content as well as bradykinesia, as determined by the rotarod test. DA-9805 protected against neuronal damage in the substantia nigra pars compacta (SNpc) and striatum. In both in vitro and in vivo models of PD, DA-9805 normalized the phosphorylation of AKT at S473 and T308 on the insulin signaling pathway and the expression of mitochondria-related genes. These results demonstrate that the triple herbal extract DA-9805 showed neuroprotective effects via alleviating mitochondria damage in experimental models of PD. We propose that DA-9805 may be a suitable candidate for disease-modifying therapeutics for PD.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a well-known environmental contaminant that exerts its toxicity through a variety of signaling mechanisms. The present study evaluated the effects of 27-deoxyactein, one of the major constituents isolated from Cimicifuga racemosa, on TCDD-induced toxicity in osteoblastic MC3T3-E1 cells. TCDD reduced cell survival, markedly increased apoptosis, and enhanced autophagy activity. However, pre-treatment with 27-deoxyactein attenuated all TCDD-induced effects and significantly decreased intracellular calcium (Ca2+) concentrations, the collapse of the mitochondrial membrane potential (MMP), the level of reactive oxygen species (ROS), and cardiolipin peroxidation compared to the TCDD-treated controls. Additionally, TCDD-induced increases in the levels of aryl hydrocarbon receptor (AhR), cytochrome P450 1A1 (CYP1A1), and extracellular signal-regulated kinase (ERK) were significantly inhibited by 27-deoxyactein. The mRNA levels of superoxide dismutase (SOD), ERK1, and nuclear factor kappa B (NF-κB) were also effectively restored by pre-treatment with 27-deoxyactein. Furthermore, 27-deoxyactein significantly increased the expressions of genes associated with osteoblast differentiation, including alkaline phosphatase (ALP), osteocalcin, bone sialoprotein (BSP), and osterix. Taken together, the present findings demonstrate the preventive effects of 27-deoxyactein on TCDD-induced damage in osteoblasts.

Background: Exposure to persistent organic pollutants (POPs), some of which are aryl hydrocarbon receptor (AhR) ligands, is suspected to cause diabetes mellitus (DM). Our previous case-control studies showed that serum AhR bioactivity (AhRB) and mitochondria inhibition potential (MIP) were enhanced in DM. Methods: In this nested case-control study, we tested whether serum AhRB and MIP could predict the future development of DM. We selected 1537 participants with normal glucose tolerance (NGT; n=919), impaired glucose tolerance (IGT; n=244), or DM (n=374) with serum samples and oral glucose tolerance tests from the 2008 Korean Genome and Epidemiologic Study. The AhRB and MIP of serum were measured by cell-based bioassays. MIP was determined by measuring the intracellular adenosine triphosphate (ATP) content and reactive oxygen species production in serum-treated cells. Findings: Among 919 subjects with NGT, 109 converted to IGT and 25 cases developed DM during the 4-year follow-up period. AhRB was higher in IGT progressors (1.97 ± 0.41-fold induction [FI] of charcoal-stripped serum control, p 2.05 FI and an ATP cutoff value ≤88.07%. Interpretation: These results suggest that exposure to AhR ligands and/or mitochondrial inhibitors may cause the development of DM and that mitochondrial dysfunction is the underlying mechanism of DM. Funding: The Korean Health Technology R&D Project Conflict of Interest: No potential conflicts of interest relevant to the article were reported Ethical Approval Statement: The study protocol was also approved by the ethics committee of the institutional review board of Ajou University School of Medicine (IRB No. AJIRB-CRO-07-012), Kyung Hee University (IRB No. KHSIRB-14-056), and Eulji University College of Medicine (IRB No. EGH2015-12-005).

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is an environmental contaminant. Xanthohumol is a prenylated flavonoid found in hops (Humulus lupulus) and beer. The aim of the current study was to explore the role of xanthohumol in modulating the toxicity of TCDD in MC3T3-E1 osteoblastic cells. In cells treated with TCDD alone, intracellular Ca

Cyclophilin A (CypA), a member of the immunophilin family, is predominantly localized in the cytoplasm. The peptidylprolyl isomerase (PPIase) activity of CypA has been demonstrated to be involved in diverse cellular processes, including intracellular protein trafficking, mitochondrial function, pre-mRNA processing, and maintenance of multiprotein complex stability. In this study, we have demonstrated that CypA regulates apoptosis signaling-regulating kinase 1 (ASK1) through its direct binding. ASK1 is a member of MAPK kinase kinase (MAP3K) family, and selectively activates both JNK and p38 MAPK pathways. Here, we also report that CypA negatively regulates phosphorylation of ASK1 at Ser966, and that CypA reduces ASK1 and its downstream kinases of the JNK and p38 signaling. ASK1 is known to induce caspase-3 activation and apoptosis, and CypA inhibited ASK1-mediated apoptosis by decrease in caspase-3 activity under cellular stress conditions. Overall, we conclude that CypA negatively regulates ASK1 functions by its physical interaction with ASK1.

Mitochondria play a central role in cell survival, and apoptotic cell death is associated with morphological changes in mitochondria. Quantification of the morphological and mechanical property changes in brain mitochondria is useful for evaluating the degree of ischemic injury and the neuroprotective effects of various drugs. This study was performed to investigate the changes in brain mitochondria in an 11-vessel occlusion ischemic model treated with magnesium sulfate (MgSO4), utilizing atomic force microscopy (AFM). Rats were randomly divided into three groups consisting of sham (n=6), global ischemia (GI, n=6), and MgSO4-treated global ischemia (MgSO4, n=6). The biophysical properties of brain mitochondria determined from AFM topographic images and adhesion force from force-distance measurements. The mean perimeter of ischemic mitochondria significantly increased to 2,396±541 nm (vs. 1,006±318 nm in control group, P0.001). The MgSO4 treatment during global ischemia reduced the perimeter of ischemic mitochondria (1,127±399 nm, P0.001). The other parameters including length, width and area were significantly different than the GI group. Besides, the adhesion force (23.2±3.9 nN) of isolated mitochondria from the MgSO4 group was close to normal levels (28.5±2.5 nN), compared with that of ischemic ones (17.7±3.3 nN, P0.001). To confirm the neuroprotective effects of MgSO4, we performed Nissl staining. This study suggested that quantitative analysis of mitochondrial changes utilizing AFM could be effective for evaluating neuronal injury and drug effects.

Recent evidence suggests that mitochondrial genomes harboring common mitochondrial DNA polymorphisms might have functional difference and could be associated with common complex human diseases such as metabolic syndrome and cancer that are related to mitochondrial dysfunction. However, there has been no report examining the functional difference of mitochondrial genome in the pathogenesis of such diseases at the cellular or molecular level. In order to examine the effect of mitochondrial genome on metabolic syndrome or cancer without interference from nuclear genes, we analyzed trans-mitochondrial cytoplasmic hybrid cells (cybrids) with common Asian mtDNA haplogroups A, B, D, and F from healthy volunteers. The mitochondrial oxygen consumption rates of cybrids were associated with multiple components of metabolic syndrome such as body mass index, waist circumference, serum triglyceride levels and high-density lipoprotein cholesterol levels. In addition, the cybrids showed varying degree of tumorigenicity both in vitro and in vivo. Especially, the cybrids harboring mtDNA haplogroup D had a significantly slower growth rate. These findings suggest that the phenotypes of common complex diseases in humans can be determined by their mitochondrial genomes. Therefore, not only nuclear genome but also mitochondrial genome should be considered in explaining the genetic pathogenesis of common complex human diseases.