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Ferroptosis is an iron-dependent form of cell death caused by the inactivation of glutathione peroxidase 4 (GPX4) and accumulation of lipid peroxides. Ferroptosis has been found to participate in the ischemia-reperfusion (I/R) injury, leading to heart dysfunction and myocardial cell death. Xanthohumol (XN), a prenylated flavonoid isolated from Humulus lupulus, has multiple pharmacological activities, such as anti-inflammatory and antioxidant. This study is aimed at investigating whether XN could attenuate the I/R-induced ferroptosis in cardiomyocytes and the underlying mechanisms. Cardiomyocytes were treated with Fe-SP and RSL3, and the rat hearts were treated with I/R. The results from the present study show that XN was able to protect cardiomyocytes against Fe-SP- and RSL3-induced ferroptotic cell death by decreasing the production of lipid peroxidation and ROS, chelating iron, reducing the NRF2 protein level, and modulating the protein levels of GPX4. Moreover, XN significantly decreased the mRNA levels of ferroptosis markers, Ptgs2 and Acsl4, and the protein levels of ACSL4 and NRF2 and modulated the protein levels of GPX4 in I/R-treated hearts. The findings from the present study suggest that XN might have the therapeutic potential for the I/R-induced ferroptosis injury.

Myocardial hypertrophy is associated with a significant increase in intracellular Ca

Coenzyme Q10 (CoQ10), a well-known antioxidant, has been explored as a treatment in several neurodegenerative diseases, but its utility in spinocerebellar ataxia type 3 (SCA3) has not been explored. Herein, the protective effect of CoQ10 was examined using a transgenic mouse model of SCA3 onset. These results demonstrated that a diet supplemented with CoQ10 significantly improved murine locomotion, revealed by rotarod and open-field tests, compared with untreated controls. Additionally, a histological analysis showed the stratification of cerebellar layers indistinguishable from that of wild-type littermates. The increased survival of Purkinje cells was reflected by the reduced abundance of TUNEL-positive nuclei and apoptosis markers of activated p53, as well as lower levels of cleaved caspase 3 and cleaved poly-ADP-ribose polymerase. CoQ10 effects were related to the facilitation of the autophagy-mediated clearance of mutant ataxin-3 protein, as evidenced by the increased expression of heat shock protein 27 and autophagic markers p62, Beclin-1 and LC3II. The expression of antioxidant enzymes heme oxygenase 1 (HO-1), glutathione peroxidase 1 (GPx1) and superoxide dismutase 1 (SOD1) and 2 (SOD2), but not of glutathione peroxidase 2 (GPx2), were restored in 84Q SCA3 mice treated with CoQ10 to levels even higher than those measured in wild-type control mice. Furthermore, CoQ10 treatment also prevented skeletal muscle weight loss and muscle atrophy in diseased mice, revealed by significantly increased muscle fiber area and upregulated muscle protein synthesis pathways. In summary, our results demonstrated biochemical and pharmacological bases for the possible use of CoQ10 in SCA3 therapy.

Background The transfer of whole mitochondria has been demonstrated to be beneficial for treating breast cancer because it induces apoptosis and drug sensitivity; however, in vivo evidence of this benefit remains scant. The present study compared the transplantation of mitochondria with instinctive (Mito) and membrane-fused morphologies induced by Pep-1 conjugation (P-Mito) using a mouse model of triple-negative breast cancers. Materials and methods Mice with advanced severe immunodeficiency received orthotopic implantation of MDA-MB-231 human breast cancer cells followed by transplants of 5-bromo-2'-deoxyuridine (BrdU)-labeled Mito or P-Mito (200 μg [10 μg/μL]) through intratumoral injection at multiple points once a week for 4 weeks. Results After 1 month of consecutive treatment, 8.2% and 14.2% of the BrdU-labeled mitochondria were preserved in tumors of the Mito and P-Mito groups, respectively. Both Pep-1 and P-Mito treatments reduced tumor weight (21.7% ± 2.43% vs 40.6% ± 2.28%) and led to marked inhibition of Ki67 staining and angiogenesis. However, only the P-Mito group exhibited obvious necrosis and DNA fragmentation accompanied by an altered tumor microenvironment, which included reduced oxidative stress and size of cancer-associated fibroblast populations and enhanced immune cell infiltration. Transmission electron microscopy images further revealed an elongated network of perinuclear mitochondria fused with a few peripheral mitochondria in the nonnecrotic area in the P-Mito group as well as increases in mitochondrial fusion proteins and parkin compared with mitochondrial fission proteins. Conclusion In this study, the results of mitochondrial transplantation emphasized that the facilitation of mitochondrial fusion is a critical regulator in breast cancer therapy.

Although the effects of growth hormone (GH) therapy on spinocerebellar ataxia type 3 (SCA3) have been examined in transgenic SCA3 mice, it still poses a nonnegligible risk of cancer when used for a long term. This study investigated the efficacy of IGF-1, a downstream mediator of GH, in vivo for SCA3 treatment. IGF-1 (50 mg/kg) or saline, once a week, was intraperitoneally injected to SCA3 84Q transgenic mice harboring a human ATXN3 gene with a pathogenic expanded 84 cytosine–adenine–guanine (CAG) repeat motif at 9 months of age. Compared with the control mice harboring a 15 CAG repeat motif, the SCA3 84Q mice treated with IGF-1 for 9 months exhibited the improvement only in locomotor function and minimized degeneration of the cerebellar cortex as indicated by the survival of more Purkinje cells with a more favorable mitochondrial function along with a decrease in oxidative stress caused by DNA damage. These findings could be attributable to the inhibition of mitochondrial fission, resulting in mitochondrial fusion, and decreased immunofluorescence staining in aggresome formation and ataxin-3 mutant protein levels, possibly through the enhancement of autophagy. The findings of this study show the therapeutic potential effect of IGF-1 injection for SCA3 to prevent the exacerbation of disease progress.

Summary: Human ubiquinol-cytochrome c reductase core protein 1 (UQCRC1) is an evolutionarily conserved core subunit of mitochondrial respiratory chain complex III. We recently identified the disease-associated variants of UQCRC1 from patients with familial parkinsonism, but its function remains unclear. Here we investigate the endogenous function of UQCRC1 in the human neuronal cell line and the Drosophila nervous system. Flies with neuronal knockdown of uqcrc1 exhibit age-dependent parkinsonism-resembling defects, including dopaminergic neuron reduction and locomotor decline, and are ameliorated by UQCRC1 expression. Lethality of uqcrc1-KO is also rescued by neuronally expressing UQCRC1, but not the disease-causing variant, providing a platform to discern the pathogenicity of this mutation. Furthermore, UQCRC1 associates with the apoptosis trigger cytochrome c (cyt-c), and uqcrc1 deficiency increases cyt-c in the cytoplasmic fraction and activates the caspase cascade. Depleting cyt-c or expression of the anti-apoptotic p35 ameliorates uqcrc1-mediated neurodegeneration. Our findings identify a role for UQCRC1 in regulating cyt-c-induced apoptosis.

Spinocerebellar ataxia (SCA) type 1 (SCA1) is a rare autosomal dominant disorder that is characterized by worsening of disordered coordination, ataxia of the trunk, and other neurological symptoms. Physical activity improves both mobility and the daily living activities of patients with SCA. Intervention with daily regular treadmill exercise may slow the deterioration of cerebellar neurons in SCA1. Therefore, the signal changes and performance of cerebellar neurons after exercise in SCA1 was investigated in this study. We employed a transgenic mouse model of SCA1, generated by amplifying the cytosine‐adenine‐guanine trinucleotide repeat expansions, and the mice underwent 1 month of moderate daily treadmill exercise for 1 hour. The rotarod test revealed that the motor function of the SCA1 mice that underwent training was superior to that of the control SCA1 mice, which did not undergo training. Moreover, the cerebellar pathology revealed preserved Purkinje neurons stained by carbindin with an increase of the neuronal Per Arnt Sim domain protein 4, a key regulation in the structural and functional plasticity of neurons, in the excised SCA1 mice relative to the controls. The mechanism was related to an increase of phosphorylation of ribosomal protein S6, a downstream target of the mammalian target of rapamycin pathway, but not to autophagy activation. This study determined that regular treadmill exercise may play a crucial role in the viable support of cerebellar neurons in SCA1.

Increasing mitochondrial fusion by intra-tumoral grafting of membrane-fused mitochondria created with Pep-1 conjugation (P-Mito) contributes to breast cancer treatment, but it needs to be validated. Using mitochondrial division inhibitor-1 (Mdivi-1, Mdi) to disturb mitochondrial dynamics, we showed that the antitumor action of P-Mito in a mouse model of triple-negative breast cancer depends upon mitochondrial fusion and that Mdi treatment alone is ineffective. P-Mito significantly enhanced Doxorubicin (Dox) sensitivity by inducing mitochondrial fusion and mitophagy, and the same efficiency was also achieved with Mdi by inhibiting mitophagy. Cell death was induced via the p53 pathway and AIF nuclear translocation in the case of P-Mito, versus the caspase-dependent pathway for Mdi. Notably, both mitochondrial treatments reduced oxidative stress and blood vessel density of xenograft tumors, especially P-Mito, which was accompanied by inhibition of nuclear factor kappa-B activation. Furthermore, through enrichment analysis, four microRNAs in serum microvesicles induced by P-Mito caused expression of predicted targets via the PI3K-Akt pathway, and significantly impacted regulation of nuclear processes and myeloid cell differentiation. Clustering of gene-sets implicated a major steroid catabolic network. This study showed diverse roles of mitochondria in breast cancer and revealed effective adjuvant therapy targeting mitochondrial fusion and mitophagy.

Spinocerebellar ataxia type 3 (SCA3) is a genetic neurodegenerative disease for which a cure is still needed. Growth hormone (GH) therapy has shown positive effects on the exercise behavior of mice with cerebellar atrophy, retains more Purkinje cells, and exhibits less DNA damage after GH intervention. Insulin-like growth factor 1 (IGF-1) is the downstream mediator of GH that participates in signaling and metabolic regulation for cell growth and modulation pathways, including SCA3-affected pathways. However, the underlying therapeutic mechanisms of GH or IGF-1 in SCA3 are not fully understood. In the present study, tissue-specific genome-scale metabolic network models for SCA3 transgenic mice were proposed based on RNA-seq. An integrative transcriptomic and metabolic network analysis of a SCA3 transgenic mouse model revealed that metabolic signaling pathways were activated to compensate for the metabolic remodeling caused by SCA3 genetic modifications. The effect of IGF-1 intervention on the pathology and balance of SCA3 disease was also explored. IGF-1 has been shown to invoke signaling pathways and improve mitochondrial function and glycolysis pathways to restore cellular functions. As one of the downregulated factors in SCA3 transgenic mice, IGF-1 could be a potential biomarker and therapeutic target.

The feasibility of delivering mitochondria intranasally so as to bypass the blood–brain barrier in treating Parkinson's disease (PD), was evaluated in unilaterally 6-OHDA-lesioned rats. Intranasal infusion of allogeneic mitochondria conjugated with Pep-1 (P-Mito) or unconjugated (Mito) was performed once a week on the ipsilateral sides of lesioned brains for three months. A significant improvement of rotational and locomotor behaviors in PD rats was observed in both mitochondrial groups, compared to sham or Pep-1-only groups. Dopaminergic (DA) neuron survival and recovery > 60% occurred in lesions of the substantia nigra (SN) and striatum in Mito and P-Mito rats. The treatment effect was stronger in the P-Mito group than the Mito group, but the difference was insignificant. This recovery was associated with restoration of mitochondrial function and attenuation of oxidative damage in lesioned SN. Notably, P-Mito suppressed plasma levels of inflammatory cytokines. Mitochondria penetrated the accessory olfactory bulb and doublecortin-positive neurons of the rostral migratory stream (RMS) on the ipsilateral sides of lesions and were expressed in striatal, but not SN DA neurons, of both cerebral hemispheres, evidently via commissural fibers. This study shows promise for intranasal delivery of mitochondria, confirming mitochondrial internalization and migration via RMS neurons in the olfactory bulb for PD therapy.

BackgroundFeasibility of mitochondrial organelle transport via the olfactory bulb route for Parkinson's disease (PD) therapy was evaluated in the unilateral 6-OHDA-lesioned rats due to the distinct difference based on payload properties. MethodsAn intranasal infusion with 200 μg of allogeneic mitochondria conjugated with Pep-1 (P-Mito) or not (Mito) was executed once a week at the ipsilateral side of lesioned brain for three months of treatments.Results A significant improvement of rotational and locomotor behaviors in PD rats was found in both mitochondria-treating groups in contrast to Sham group or Pep-1 group. There was more than 60% recovery survival of dopaminergic (DA) neurons in substantia nigra (SN) and striatum (ST) of lesioned sides compared to the intact sides in groups of Mito and P-Mito. Treatment effect in P-Mito group was higher in the P-Mito group than Mito group but not significant. The mechanism was associated with the restoration of mitochondrial function and attenuation of oxidative damage in lesioned SN. Notably, Pep-1 modification suppressed the plasma level of inflammatory cytokines induced by infused mitochondria. The 5-bromo-2-deoxyuridine-labelled tracks showed the mitochondrial penetrating into doublecortin-positive neurons of rostral migratory stream (RMS) along with the accessory olfactory bulb in ipsilateral side of lesion and it was expressed in striatal DA neurons, but not in SN, of two cerebral hemispheres via commissural fibers. Conclusion This study showed a promising approach of nose-to-brain delivery for mitochondrial transplantation by confirming the mitochondrial internalization via RMS neurons migration in olfactory bulb for therapeutic action of PD in rats.

Spinocerebellar ataxia type 3 (SCA3) is a fatal neurodegenerative disease for which no identified effective treatment or prevention methods exist. However, low-dose growth hormone (GH) therapy, as a potential off-label use, may deter the progress of SCA3. SCA3 15Q and SCA3 84Q transgenic mice harboring a YAC transgene that expresses the human ATXN3 gene with a pathogenic expanded 15 CAG repeat and 84 CAG repeat motif, respectively, were recruited. SCA3 15Q transgenic mice were considered as the healthy control group, whereas low-dose GH- and PBS-treated SCA3 84Q transgenic mice were considered as the study and sham groups, respectively. The SCA3 84Q transgenic mice were administered intraperitoneal injections of GH or PBS weekly from the postnatal age of 9 months–18 months. After 9 months of GH treatment in the SCA3 84Q transgenic mice, all locomotor functions including rotarod test, behavior box analysis were restored. The GH-treated SCA3 84Q transgenic mice revealed more preserved Purkinje cells/cerebellar cortex and less ataxin-3 aggregation, DNA oxidative, cell apoptosis compared with the PBS-treated SCA3 84Q transgenic mice. GH therapy may be one of the potential off-labeled using in the alleviation of SCA3 progression.

Spinocerebellar ataxia type 3 (SCA3) is a polyglutamine neurodegenerative disease resulting from the misfolding and accumulation of a pathogenic protein, causing cerebellar dysfunction, and this disease currently has no effective treatments. Far-infrared radiation (FIR) has been found to protect the viability of SCA3 cells by preventing mutant ataxin-3 protein aggregation and promoting autophagy. However, this possible treatment still lacks in vivo evidence. This study assessed the effect of FIR therapy on SCA3 in vivo by using a mouse model over 28 weeks. Control mice carried a healthy wild-type ATXN3 allele that had a polyglutamine tract with 15 CAG repeats (15Q), whereas SCA3 transgenic mice possessed an allele with a pathological polyglutamine tract with expanded 84 CAG (84Q) repeats. The results showed that the 84Q SCA3 mice displayed impaired motor coordination, balance abilities, and gait performance, along with the associated loss of Purkinje cells in the cerebellum, compared with the normal 15Q controls; nevertheless, FIR treatment was sufficient to prevent those defects. FIR significantly improved performance in terms of maximal contact area, stride length, and base support in the forepaws, hindpaws, or both. Moreover, FIR treatment supported the survival of Purkinje cells in the cerebellum and promoted the autophagy, as reflected by the induction of autophagic markers, LC3II and Beclin-1, concomitant with the reduction of p62 and ataxin-3 accumulation in cerebellar Purkinje cells, which might partially contribute to the rescue mechanism. In summary, our results reveal that FIR confers therapeutic effects in an SCA3 transgenic animal model and therefore has considerable potential for future clinical use.

Purpose Parkinson's disease (PD) is a progressive degenerative central nervous system disorder that particularly impairs motor function. As PD advances, gait disorders become more pronounced and are often difficult to treat with current pharmacological therapies. Physical activity improves both mobility in and the daily living activities of patients with PD. Mitochondrial alterations and oxidative stress contribute to PD progression. Therefore, the association between mitochondria and exercise in PD and the implicated regulation of mitochondrial proteins was explored in this study. Methods In this study, we developed a unilateral 6-hydroxydopamine rat model of PD and executed 4 weeks of treadmill training. Motor behavior was evaluated through gait change analysis (the CatWalk method) and rotational testing. The viability of dopaminergic neurons, mitochondrial function, and oxidative stress in the substantia nigra and striatum were investigated through Western blot and immunohistochemical staining. Key findings Treadmill training improved the performance of gait parameters in terms of maximal area, swing speed, stride length, and stance phase; treadmill training also reduced methamphetamine-induced rotation. This training not only improved dopaminergic neuron viability but also recovered mitochondrial function and attenuated oxidative stress in PD rats. The mechanism may be associated with the facilitation of mitochondrial turnover, including facilitation of mitochondrial fusion, fission, and clearance accompanying increased quantities of mitochondria. Significance Treadmill exercise improved gait speed and balance, reduced oxidative stress, improved mitochondrial fusion and fission, increased mitochondrial amounts, and potentially attenuated dopaminergic neuron degeneration. Consequently, mitochondrial quality was improved in PD rats.

Spinocerebellar ataxia type 3 (SCA3) is caused by the expansion of a polyglutamine (polyQ) repeat in the protein ataxin-3 which is involved in susceptibility to mild oxidative stress induced neuronal death. Here we show that caffeic acid (CA) and resveratrol (Res) decreased reactive oxygen species (ROS), mutant ataxin-3 and apoptosis and increased autophagy in the pro-oxidant tert-butyl hydroperoxide (tBH)-treated SK-N-SH-MJD78 cells containing mutant ataxin-3. Furthermore, CA and Res improved survival and locomotor activity and decreased mutant ataxin-3 and ROS levels in tBH-treated SCA3 Drosophila. CA and Res also altered p53 and nuclear factor-κB (NF-κB) activation and expression in tBH-treated cell and fly models of SCA3, respectively. Blockade of NF-κB activation annulled the protective effects of CA and Res on apoptosis, ROS, and p53 activation in tBH-treated SK-N-SH-MJD78 cells, which suggests the importance of restoring NF-κB activity by CA and Res. Our findings suggest that CA and Res may be useful in the management of oxidative stress induced neuronal apoptosis in SCA3.

Background The transfer of whole mitochondria has been demonstrated to be beneficial for treating breast cancer because it induces apoptosis and drug sensitivity; however, in vivo evidence of this benefit remains scant. The present study compared the transplantation of mitochondria with instinctive (Mito) and membrane-fused morphologies induced by Pep-1 conjugation (P-Mito) using a mouse model of triple-negative breast cancers. Materials and Methods Mice with advanced severe immunodeficiency received orthotopic implantation of MDA-MB-231 human breast cancer cells followed by transplants of 5-bromo-2ʹ-deoxyuridine (BrdU)-labeled Mito or P-Mito (200 μg [10 μg/μL]) through intratumoral injection at multiple points once a week for 4 weeks. Results After 1 month of consecutive treatment, 8.2% and 14.2% of the BrdU-labeled mitochondria were preserved in tumors of the Mito and P-Mito groups, respectively. Both Pep-1 and P-Mito treatments reduced tumor weight (21.7% ± 2.43% vs 40.6% ± 2.28%) and led to marked inhibition of Ki67 staining and angiogenesis. However, only the P-Mito group exhibited obvious necrosis and DNA fragmentation accompanied by an altered tumor microenvironment, which included reduced oxidative stress and size of cancer-associated fibroblast populations and enhanced immune cell infiltration. Transmission electron microscopy images further revealed an elongated network of perinuclear mitochondria fused with a few peripheral mitochondria in the nonnecrotic area in the P-Mito group as well as increases in mitochondrial fusion proteins and parkin compared with mitochondrial fission proteins. Conclusion In this study, the results of mitochondrial transplantation emphasized that the facilitation of mitochondrial fusion is a critical regulator in breast cancer therapy.

The yield and efficacy of bioactive compounds from Cordyceps militaris fruiting bodies and its fermented grains usually vary with the strain used. In this study, we compared the antiproliferative, apoptotic, and antioxidative properties of ethanolic extracts of fruiting bodies and solid-stated fermented rice (FRE) from two wild-type strains of C. militaris applied to human breast cancer cell lines. We observed that FRE of the Zhangzhou strain (FRE-Z) produced a high level of cordycepin and exhibited comprehensive in vitro antioxidant activity against the oxidation of 2,2-diphenyl-1-picrylhydrazyl, superoxide, and hydroxyl radicals and low-density lipoprotein. Only FRE-Z exhibited dose-dependent inhibition of cell proliferation in MCF-7 (0.7 mg/mL) and MDA-MB-231 cells (1 mg/mL) after culturing for 24 h. The antiproliferative effects of FRE-Z were associated with an early stage of apoptosis induction at 4 h of treatment with 0.5 mg/mL FRE-Z in MCF-7 cells. The antiproliferative effect was determined to occur through p53 activation but not through the release of mitochondrial apoptosis-inducing factor or caspase-9 activation for an initial culture period of 16 h. In addition to a transient increase in cellular antioxidant enzyme, Cu/Zn superoxide dismutase was identified in MCF-7 cells after 2 h of treatment with FRE-Z. Therefore, FRE-Z, which exhibits various dose- and exposure time-dependent activities, has potential application in breast cancer chemoprevention.

In this research, we propose a novel centrifugal device for the massive extraction of healthy mitochondria with a centrifuge used in general laboratories within 30 minutes. The device mainly consists of two key components. One component is a microfluidic device, which is fabricated by photolithography, nickel electroforming, and polydimethylsiloxane casting, for the efficient disruption of the cell membrane. The other component is a stainless steel container, which is manufactured by computer numerical control machining, for the storage of the cell suspension. After assembly, the appropriate number of cells is pushed through the microfluidic device for cell membrane disruption by centrifugal force generated by a general laboratory centrifuge. The solution which contains cell debris and mitochondria are collected to purify the crude mitochondria via differential centrifugation. Compared with the quantity and efficiency of mitochondria isolated from the same number of cells using a conventional kit, device-extracted mitochondria show a more complete mitochondrial electron transport chain complex and a similar number of mitochondria verified by Western blot analysis of mitochondrial complexes I-V and mitochondrial outer membrane protein Tom20, respectively, as well as a normal mitochondrial structure revealed by transmission electron microscopy. Moreover, the mitochondrial membrane potential of device-extracted mitochondria stained with tetramethylrhodamine ethyl ester is higher than that of kit-extracted mitochondria. Furthermore, the coculture of device-extracted mitochondria with fibroblasts revealed that fibroblasts could uptake foreign mitochondria through endocytosis without drug treatment. These results show that the proposed microfluidic device preserves mitochondrial protein structure, membrane integrity, and membrane potential within 30 minutes of extraction and is a useful tool for therapeutic mitochondrial transplantation and regenerative medicine.

Objective: Tissue hypoperfusion during cardiopulmonary bypass (CPB) affects cardiac surgical outcomes. Lactate, an end product of anaerobic glycolysis from oxygen deficit, is a marker of tissue hypoxia. In this study, we aimed to identify the prognostic value of blood lactate level during CPB in predicting outcomes in adults undergoing cardiac surgeries. Materials and Methods: We retrospectively reviewed the medical records of patients who underwent cardiac surgeries with CPB from January 2015 to December 2015. Data about the characteristics of patients, preoperative status, type of surgery, and intraoperative lactate levels were collected. The outcomes were in-hospital mortality and complications. The receiver operating characteristics (ROC) curves were used to assess the ability of peak lactate level during CPB in predicting in-hospital mortality. Results: A total of 97 patients, including 61 who underwent emergent or urgent surgery, were enrolled. The types of surgery included coronary artery bypass grafting (CABG, n = 52), valve surgery (n = 27), combined surgery (CABG and valve surgery, n = 4), great vessel surgery (including aortic dissection, n = 9), and others (n = 5). The median CPB time was 139 min (interquartile range = 120–175). The median initial lactate and peak lactate levels during CPB were 0.9 and 4.2 mmol/L, respectively. In-hospital mortality was 14.4%, which was significantly associated with age and peak lactate level in the multivariate logistic regression model. When the peak lactate level during CPB reached 7.25 mmol/L, in-hospital mortality could be predicted with an area under the ROC curve of 0.75 (95% confidence interval: 0.59–0.90; P = 0.003), with a sensitivity of 57% and specificity of 93%. Conclusion: Hyperlactatemia during CPB was associated with increased in-hospital mortality. Thus, early detection of such conditions and aggressive postoperative care are important.

A detection and degradation platform was developed to optically quantify the 6-enolate, 8-keto-dG, an important tautomer of mitochondrial mutated DNA 8-oxo-dG. We first found that 6-enolate, 8-keto-dG offers particular fluorescence emission under the conditions between pH ∼ 7 and ∼11. Thus, a mitochondria-targeting photosensitizer NV-12P was prepared to offer simultaneously photoinduced electron transfer and fluorescence resonance energy transfer (FRET) with 6-enolate, 8-keto-dG. Furthermore, NV-12P can also generate a reactive oxygen species to degrade 6-enolate, 8-keto-dG under irradiation conditions. This is the first publication about optical characterization, concentration detection and photodegradation of 6-enolate, 8-keto-dG, either in biological or in vitro applications.

Transferring exogenous mitochondria has therapeutic effects on damaged heart, liver, and lung tissues. Whether this protective effect requires the symbiosis of exogenous mitochondria in host cells remains unknown. Here xenogenic mitochondria derived from a hamster cell line were applied to ischemic rat brains and rat primary cortical neurons. Isolated hamster mitochondria, either through local intracerebral or systemic intra-arterial injection, significantly restored the motor performance of brain-ischemic rats. The brain infarct area and neuronal cell death were both attenuated by the exogenous mitochondria. Although internalized mitochondria could be observed in neurons and astrocytes, the low efficacy of mitochondrial internalization could not completely account for the high rate of rescue of the treated neural cells. We further illustrated that disrupting electron transport or ATPase synthase in mitochondria significantly attenuated the protective effect, suggesting that intact respiratory activity is essential for the mitochondrial potency on neural protection. These results emphasize that nonsymbiotic extracellular mitochondria can provide an effective cell defense against acute injurious ischemic stress in the central nervous system.

Introduction Cells intake nutrients and oxygen to produce cellular energy (adenosine triphosphate, ATP) and simultaneously excrete acidic waste and carbon dioxide. Cell activity can be estimated by measuring cellular metabolism-related molecules, such as oxygen and proton. Furthermore, the rate of oxidative phosphorylation (OXPHOS) can be used as a probe to evaluate carcinomatosis degree. Normal cells produce ATP via OXPHOS, but cancer cells mainly produce ATP via cytosol glycolysis, which consumes less oxygen and produces more protons. Therefore, to measure the consuming rate of oxygen and the change in extracellular pH values is meaningful for the estimation of cell activity and carcinomatosis degree. In our previous studies [1-4], Clark and non-Clark oxygen sensing chips were designed and fabricated for estimating the respiratory activity of mammalian cells, such as HeLa cells [3]. The time-lapse monitoring shows that the respiratory activity of HeLa cells increases with the cultivation time. Moreover, an oxygen electrode array integrated with a microfluidic channel and microstructures can be constructed to measure the oxygen consumption rate of single bovine embryo for the estimation of embryo development [2]. It is worth noting that the microfluidic flow of cell-based chip may induce a shear force or a viscous force to move the attached cell away from the detecting electrodes during medium replacement. In our previous study, a cell-based chip consisting of position-raised microchannel, an open chamber slab and a IrOx-deposited microelectrode-containing substrate was developed for the measurement of extracellular acidification. The position-raised microchannel can reduce the effect of shear force on the cell attachment during perform medium replacement. The design of cell-based chip was used to construct a platform to estimate the mitochondria activity of adipocytes and monocytes. In this presentation, I will introduce the recent progress of cell-based chip in the applications of estimating mitochondria activity. Measuring the activity of low cell-matrix adhesion-type cells Adipocyte activity determines the metabolism of carbohydrate and fatty acid of human beings, related to the formation of diabetes. Evaluation of adipocyte activity allows the researchers to realize the causes of type II diabetes and therapeutic methods. In the study, a microfluidic chip containing dissolved oxygen (DO) sensors of three-electrode electrochemical system was developed for the measurement of DO around the cultivated adipocytes. Moreover, the iridium oxide (IrOx) layer was electrodeposited on a gold electrode as the reference electrode. Adipocytes were estimated with the stimulation of different glucose concentration, insulin and mitochondria activity-controlled drugs, such as oligomycin, FCCP, rotenone . Method The microfluidic chip comprises a poly(dimethylsiloxane) (PDMS) slab containing a microchannel-connected container and a glass substrate containing IrOx-electrodeposited gold ultramicroelectrode. The schematic cross-section structure of chip is shown in Fig. 1. The PDMS slab is constructed for the purpose of cell culture and fluidic control of medium by means of the open container and the position-raised microchannel, respectively. A 50-mm thick PDMS membrane prepared by spin-coating on polyacrylate substrate was irreversibly bonded with the bottom side of PDMS microchannel replica using oxygen plasma treatment to act as a spacer for raising the position of the microchannel. Furthermore, the PDMS spacer locating between the open container and the reference electrode setting container can increase the liquid-junction area between the DO electrodes and the IrOx reference electrode. Finally, a Teflon tubing was connected to the outlet of position-raised microchannel and the other end of tubing was connected with a pump. 50-nm Ti and 250-nm Au thin films were patterned on the glass substrate as the working electrodes. Subsequently, a 10-mm thick negative photoresist, SU8-3010, was employed to define the sensitive area of electrodes. Furthermore, a self-made plexiglass clamp was used to enhance the fixation between the PDMS slab and the glass substrate. Results and Conclusions Figure 2 shows the optical images of adipocytes before and after medium replacement. The result shows the low-adhesion-type adipocyte don’t move during the fluidic replacement via the position-raised microchannel. A pulse amperometry was used for the measurement of DO concentration at -0.7 V for 120 s with 5 min time interval, shown in Fig. 3. The reductive current of DO is proportional to DO concentration. When applying different mitochondria activity-modulated drugs, the oxygen consumption rate was good correlation with cellular physiological behavior. For example, oligomycin is a ATPase inhibitor, which decreased the oxygen consumption rate (OCR). FCCP is an uncoupling protein, dissipating proton gradient, to increase mitochondria activity, which increases OCR. The DO microfluidic chip has a great promise in the application of estimating the effect of drugs on the cellular physiological behavior to replace animal and clinical experiments, and estimate the mitochondria activity to realize the degree and metabolic aging. References [1] C.-C.Wu, T. Yasukawa, H. Shiku, T. Matsue, Fabrication of miniature Clark oxygen sensor integrated with microstructure, Sensors and Actuators B 110 (2005) 342–349. doi.org/10.1016/j.snb.2005.02.014. [2] C.-C.Wu, T. Saito, T. Yasukawa, H. Shiku, H. Abe, H. Hoshi, T. Matsue, Microfluidic chip integrated with amperometric detector array for in situ estimating oxygen consumption characteristics of single bovine embryos, Sensors and Actuators B 125 (2007) 680–687. doi.org/10.1016/j.snb.2007.03.017. [3] C.-C. Wu, H.-N. Luk, Y.-T. Tsai Lin, C.-Y. Yuan, A Clark-type oxygen chip for in situ estimation of the respiratory activity of adhering cells, Talanta 81 (2010) 228–234. doi: 10.1016/j.talanta.2009.11.062 [4] C.-C.Wu, W.-C. Lin, S.-Y. Fu, The open container-used microfluidic chip using IrOx ultramicroelectrodes for the in situ measurement of extracellular acidification, Biosensors and Bioelectronics 26 (2011) 4191–4197. doi.org/10.1016/j.bios.2011.04.034 Figure 1

Supplementary methods. (DOCX 20 kb)

Olfactory dysfunction has been recently identified as one of the earliest non-motor symptoms of Parkinson’s disease (PD); it occurs at an early stage in approximately 90% of patients with PD and can be observed several years before the onset of limb disorders...