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Skeletal muscle function is highly dependent on the energy supply provided by mitochondria. Besides ATP production, mitochondria have several other roles, such as calcium storage, heat production, cell death signaling, autophagy regulation and redox state modulation. Mitochondrial function is crucial for skeletal muscle fiber formation. Disorders that affect mitochondria have a major impact in muscle development and function. Here we studied the role of mitochondria during chick skeletal myogenesis. We analyzed the intracellular distribution of mitochondria in myoblasts, fibroblasts and myotubes using Mitotracker labeling. Mitochondrial respiration was investigated in chick muscle cells. Our results show that (i) myoblasts and myotubes have more mitochondria than muscle fibroblasts; (ii) mitochondria are organized in long lines within the whole cytoplasm and around the nuclei of myotubes, while in myoblasts they are dispersed in the cytoplasm; (iii) the area of mitochondria in myotubes increases during myogenesis, while in myoblasts and fibroblasts there is a slight decrease; (iv) mitochondrial length increases in the three cell types (myoblasts, fibroblasts and myotubes) during myogenesis; (v) the distance of mitochondria to the nucleus increases in myoblasts and myotubes during myogenesis; (vi) Rotenone inhibits muscle fiber formation, while FCCP increases the size of myotubes; (vii) N-acetyl cysteine (NAC), an inhibitor of ROS formation, rescues the effects of Rotenone on muscle fiber size; and (viii) Rotenone induces the production of ROS in chick myogenic cells. The collection of our results suggests a role of ROS signaling in mitochondrial function during chick myogenesis. • Mitochondrial respiration is modulated during myogenesis. • Distance of mitochondria to the nucleus increases in myoblasts during myogenesis. • Rotenone inhibits muscle fiber formation, while FCCP increases the size of myotubes. • N-acetyl cysteine rescues the effects of Rotenone on muscle fiber size. • We suggest a role of ROS signaling in mitochondrial function during myogenesis. [ABSTRACT FROM AUTHOR]

Sodium-glucose co-transporter 2 (SGLT 2) inhibitors are a relatively new antidiabetic drug with antioxidant and anti-inflammatory properties. Therefore, this study aimed to investigate whether SGLT 2 inhibitors have a neuroprotective effect in PD. Twenty-four Wistar rats were randomized into four groups. The first one (control group) received dimethyl sulfoxide (DMSO) as a vehicle (0.2 mL/48 hr, S.C). The second group (positive control) received rotenone (ROT) (2.5 mg/kg/48 hr, S.C) for 20 successive days, whereas the third and fourth groups received empagliflozin (EMP) (1 and 2 mg/kg/day, orally), respectively. The two groups received rotenone (2.5 mg/kg/48 hr S.C) concomitantly with EMP for another 20 days on the fifth day. By the end of the experimental period, behavioral examinations were done. Subsequently, rats were sacrificed, blood samples and brain tissues were collected for analysis. ROT significantly elevated oxidative stress and proinflammatory markers as well as α-synuclein. However, dopamine (DP), antioxidants, tyrosine hydroxylase (TH), and Parkin were significantly decreased. Groups of (EMP + ROT) significantly maintained oxidative stress and inflammatory markers elevation, maintained α-synuclein and Parkin levels, and elevated TH activity and dopamine level. In both low and high doses, EMP produced a neuroprotective effect against the PD rat model, with the high dose inducing a more significant effect. [ABSTRACT FROM AUTHOR]

• α-Synuclein (αS) is a synaptic protein up-regulated in Parkinson's disease. • SH-SY5Y neuroblastoma cells were engineered to overexpress αS at low and high levels. • High-αS overexpression stimulates cell proliferation and delay senescence. • Low-αS overexpression causes toxicity, oxidative stress, and accelerates senescence. • A fine-tuned up-regulation of αS is critical for neuronal maintenance and survival. Alpha-Synuclein (aSyn) is a chameleon-like protein. Its overexpression and intracellular deposition defines neurodegenerative α-synucleinopathies including Parkinson's disease. Whether aSyn up-regulation is the cause or the protective reaction to α-synucleinopathies remains unresolved. Remarkably, the accumulation of aSyn is involved in cancer. Here, the neuroblastoma SH-SY5Y cell line was genetically engineered to overexpress aSyn at low and at high levels. aSyn cytotoxicity was assessed by the MTT and vital-dye exclusion methods, observed at the beginning of the sub-culture of low-aSyn overexpressing neurons when cells can barely proliferate exponentially. Conversely, high-aSyn overexpressing cultures grew at high rates while showing enhanced colony formation compared to low-aSyn neurons. Cytotoxicity of aSyn overexpression was indirectly revealed by the addition of pro-oxidant rotenone. Pretreatment with partially reduced graphene oxide, an apoptotic agent, increased toxicity of rotenone in low-aSyn neurons, but, it did not in high-aSyn neurons. Consistent with their enhanced proliferation, high-aSyn neurons showed elevated levels of SMP30, a senescence-marker protein, and the mitosis Ki-67 marker. High-aSyn overexpression conferred to the carcinogenic neurons heightened tumorigenicity and resistance to senescence compared to low-aSyn cells, thus pointing to an inadequate level of aSyn stimulation, rather than the aSyn overload itself, as one of the factors contributing to α-synucleinopathy. [ABSTRACT FROM AUTHOR]

Background: Nonvitamin A apocarotenoids occur in foods. Some function as retinoic acid receptor antagonists in vitro, though it is unclear if apocarotenoids are absorbed or accumulate to levels needed to elicit biological function. Objective: The aim of this study was to quantify carotenoids and apocarotenoids (β-apo-8′-, -10′-, -12′-, and -14′-carotenal, apo-6′-, -8′-, -10′-, -12′-, and -14′-lycopenal, retinal, acycloretinal, β-apo-13-carotenone, and apo-13-lycopenone) in human plasma after controlled consumption of carotenoid-rich tomato juices. Design: Healthy subjects (n = 35) consumed a low-carotenoid diet for 2 wk, then consumed 360 mL of high-β-carotene tomato juice (30.4 mg of β-carotene, 34.5 μg total β-apocarotenoids/d), high-lycopene tomato juice (42.5 mg of lycopene, 119.2 μg total apolycopenoids/d), or a carotenoid-free control (cucumber juice) per day for 4 wk. Plasma was sampled at baseline (after washout) and after 2 and 4 wk, and analyzed for carotenoids and apocarotenoids using high-pressure liquid chromatography (HPLC) and HPLC-tandem mass spectrometry, respectively. The methods used to analyze the apocarotenoids had limits of detection of ∼ 100 pmol/L. Results: Apocarotenoids are present in tomato juices at 0.1–0.5% of the parent carotenoids. Plasma lycopene and β-carotene increased (P < 0.001) after consuming high-lycopene and β-carotene tomato juices, respectively, while retinol remained unchanged. β-Apo-13-carotenone was found in the blood of all subjects at every visit, although elevated (P < 0.001) after consuming β-carotene tomato juice for 4 wk (1.01 ± 0.27 nmol/L) compared with both baseline (0.37 ± 0.17 nmol/L) and control (0.46 ± 0.11 nmol/L). Apo-6′-lycopenal was detected or quantifiable in 29 subjects, while β-apo-10′- and 12′-carotenal were detected in 6 and 2 subjects, respectively. No other apolycopenoids or apocarotenoids were detected. Conclusions: β-Apo-13-carotenone was the only apocarotenoid that was quantifiable in all subjects, and was elevated in those consuming high-β-carotene tomato juice. Levels were similar to previous reports of all-trans-retinoic acid. Other apocarotenoids are either poorly absorbed or rapidly metabolized or cleared, and so are absent or limited in blood. β-Apo-13-carotenone may form from vitamin A and its presence warrants further investigation. [ABSTRACT FROM AUTHOR]

Background: Mitochondrial dysfunction and reactive oxygen species (ROS) generation cause dopaminergic neurodegeneration in Parkinson's disease. The neuroprotective approach is a promising strategy to slow disease progression in Parkinson's disease. A standardized extract of Centella asiatica ECa233 has been previously reported to have pharmacological effects in the central nervous system.Purpose: This study aimed to determine the neuroprotective effect and mechanisms of ECa233 in rotenone-induced parkinsonism rats.Methods: Rats were orally given either vehicle or ECa233 (10, 30 and 100 mg/kg) for 20 consecutive days. Rotenone (2.5 mg/kg i.p.) was given to parkinsonism (PD) and ECa-treated rats from day 15 to 20. Locomotor activity was recorded on day 1, 14, 17 and 20. Tyrosine-hydroxylase (TH) immunohistological staining was used to determine dopaminergic neurons in the substantia nigra and striatum. Furthermore, mitochondrial complex I activity, malondialdehyde (MDA) levels, superoxide dismutase (SOD) and catalase protein expression were measured in brain tissue.Results: Rats receiving ECa233 30 mg/kg showed a significant increase in distances (p < 0.01) together with a higher number and intensity of dopaminergic neurons in the substantia nigra and striatum (p < 0.001) compared to PD rats. ECa233 (30 mg/kg) protected against mitochondrial complex I inhibition, decreased MDA levels (p < 0.05) and increased SOD (p < 0.01) and catalase (p < 0.05) expression.Conclusion: ECa233 can protect against rotenone-induced motor deficits and dopaminergic neuronal death. These effects are mediated through the protection of mitochondrial complex I activity, the effects of antioxidants and the enhancement of antioxidant enzyme expression. [ABSTRACT FROM AUTHOR]

Ghrelin, a 28-amino acid peptide hormone, has protective effects on neuronal cells. The present study aimed to examine the neuroprotective effects of ghrelin on the rat retinal ganglion cells in the rotenone-induced in vitro model of Parkinson's disease (PD). Cell viability and cell apoptosis were determined by MTT assay and flow cytometry, respectively. Mitochondrial functions were detected by mitochondrial complex I activity assay and mitochondrial membrane potential (MMP) assay. The mRNA and protein expression levels were determined by qRT-PCR and western blot, respectively. Rotenone significantly suppressed cell viability and increased cell apoptosis, also decreased the mitochondrial complex I activity as well as MMP in rat retinal ganglion cell line (RGC-5). Growth hormone secretagogue receptor ( Ghsr ) siRNA transfection significantly suppressed the expression of Ghsr in RGC-5 cells. Ghrelin treatment attenuated the effects of rotenone-induced changes in cell viability, cell apoptosis and mitochondrial functions in RGC-5 cells. Post-transcriptional suppression by Ghsr siRNA transfection and treatment with GHS-R antagonist, YIL781, both significantly attenuated the effects of ghrelin in RGC-5 cells. Rotenone decreased the protein levels of Bcl-2 and increased the protein levels of Bax, cleaved caspase-3 and cleaved caspase-9, and this effect was reversed by ghrelin treatment. Ghrelin also prevented the inhibitory effects of rotenone on the AKT-mTOR signaling. The effects of ghrelin on the rotenone-induced changes in apoptosis-related protein levels and AKT-mTOR signaling were attenuated by Ghsr siRNA transfection and treatment with YIL781 in the RGC-5 cells. In addition, both rapamycin and AKT inhibitor IV pre-treatment significantly attenuated the effects of ghrelin on rotenone-induced changes in cell viability and cell apoptosis. In conclusion, ghrelin by acting on the GSH-R to protect rat retinal ganglion cells against rotenone via inhibiting apoptosis and restore mitochondrial functions in RGC-5 cells, and this effect was partially associated with the AKT-mTOR signaling pathway in RGC-5 cells. [ABSTRACT FROM AUTHOR]

Objective Brown adipocytes (BAs) are endowed with a high metabolic capacity for energy expenditure due to their high mitochondria content. While mitochondrial pH is dynamically regulated in response to stimulation and, in return, affects various metabolic processes, how mitochondrial pH is regulated during adrenergic stimulation-induced thermogenesis is unknown. We aimed to reveal the spatial and temporal dynamics of mitochondrial pH in stimulated BAs and the mechanisms behind the dynamic pH changes. Methods A mitochondrial targeted pH-sensitive protein, mito-pHluorin, was constructed and transfected to BAs. Transfected BAs were stimulated by an adrenergic agonist, isoproterenol. The pH changes in mitochondria were characterized by dual-color imaging with indicators that monitor mitochondrial membrane potential and heat production. The mechanisms of pH changes were studied by examining the involvement of electron transport chain (ETC) activity and Ca 2+ profiles in mitochondria and the intracellular Ca 2+ store, the endoplasmic reticulum (ER). Results A triphasic mitochondrial pH change in BAs upon adrenergic stimulation was revealed. In comparison to a thermosensitive dye, we reveal that phases 1 and 2 of the pH increase precede thermogenesis, while phase 3, characterized by a pH decrease, occurs during thermogenesis. The mechanism of pH increase is partially related to ETC. In addition, the pH increase occurs concurrently with an increase in mitochondrial Ca 2+ . This Ca 2+ increase is contributed to by an influx from the ER, and it is further involved in mitochondrial pH regulation. Conclusions We demonstrate that an increase in mitochondrial pH is implicated as an early event in adrenergically stimulated BAs. We further suggest that this pH increase may play a role in the potentiation of thermogenesis. [ABSTRACT FROM AUTHOR]

Several lines of evidence suggest that endoplasmic reticulum (ER) stress plays a critical role in the pathogenesis of many neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. Protein tyrosine phosphatase 1B (PTP1B) is known to regulate the ER stress signaling pathway, but its role in neuronal systems in terms of ER stress remains largely unknown. Here, we showed that rotenone-induced toxicity in human neuroblastoma cell lines and mouse primary cortical neurons was ameliorated by PTP1B inhibition. Moreover, the increase in the level of ER stress markers (eIF2α phosphorylation and PERK phosphorylation) induced by rotenone treatment was obviously suppressed by concomitant PTP1B inhibition. However, the rotenone-induced production of reactive oxygen species (ROS) was not affected by PTP1B inhibition, suggesting that the neuroprotective effect of the PTP1B inhibitor is not associated with ROS production. Moreover, we found that MG132-induced toxicity involving proteasome inhibition was also ameliorated by PTP1B inhibition in a human neuroblastoma cell line and mouse primary cortical neurons. Consistently, downregulation of the PTP1B homologue gene in Drosophila mitigated rotenone- and MG132-induced toxicity. Taken together, these findings indicate that PTP1B inhibition may represent a novel therapeutic approach for ER stressmediated neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

The pesticide rotenone has been shown to cause systemic inhibition of mitochondrial complex I activity, with consequent degeneration of dopamine neurons along the nigrostriatal pathway, as observed in Parkinson’s disease (PD). Recently, intracranial infusion of rotenone was found to increase the protein levels of the Lewy body constituents, α-synuclein and small ubiquitin-related modifier-1(SUMO-1), in the lesioned hemisphere of the mouse brain. These findings are supportive of a mouse model of PD, but information about the dopamine-synthesizing enzyme, tyrosine hydroxylase (TH), an essential marker of dopaminergic status, was not reported. Clarification of this issue is important because an intracranial rotenone mouse model of Parkinson's disease has not been established. Towards this end, the present study examined the effects of intracranial rotenone treatment on TH and α-synuclein immunohistochemistry in addition to forelimb motor function. Mice were unilaterally infused with either vehicle or rotenone (2 μg/site) in both the medial forebrain bundle and the substantia nigra. The forelimb asymmetry (cylinder) test indicated a significant decrease in use of the contralateral forelimb in lesioned animals as compared to the sham group. Densitometric analysis revealed a significant depletion of TH immunofluorescence within the ipsilateral striatum and substantia nigra of lesioned animals. Moreover, a significant bilateral increase in α-synuclein immunofluorescence was found in the substantia nigra of lesioned mice, as compared to control animals. These findings indicate that this intracranial rotenone mouse model will be useful for studies of neurodegenerative disorders such as PD. [ABSTRACT FROM AUTHOR]

Combinations of Ginkgo biloba (G. biloba) extract (active ingredient ginkgolic acid (GA)) and Derris trifoliata (D. trifoliata) extract (active ingredient rotenone (R)) were evaluated through bioassays and field trials to develop botanical insecticides as alternatives to chemical pesticides for aphid control. The bioassay results showed that the G. biloba extract exhibited high insecticidal activity against Acyrthosiphon pisum , Myzus persicae , and Aphis spiraecola adults, with LC 50 values of 333.89 μg/mL, 282.52 μg/mL, and 250.41 μg/mL, respectively. D. trifoliata extract exhibited better insecticidal activity against A. pisum, M. persicae , and A. spiraecola adults, with LC 50 values of 19.22 μg/mL, 12.70 μg/mL, and 3.99 μg/mL, respectively. Moreover, the extract combination of G. biloba and D. trifoliata at a ratio of 84:16 exhibited significant synergy against A. pisum , with a cotoxicity coefficient of 219.01. Additionally, two insecticidal formulations of 23% GA soluble liquid (SL) and 11.5% GA-R SL were developed using G. biloba extract (GA) and G. biloba with D. trifoliata extract (GA-R) combinations as the active substances. Field trials in 2020 and 2021 indicated that 11.5% GA-R SL had efficacies of 84.38% and 85.19%, respectively, against A. spiraecola seven days after a 721.28 a.i. g/hm2 application; 23% GA SL had 65.33% and 66.09% efficacies, respectively, against A. spiraecola seven days after a 1442.56 a.i. g/hm2 application. Based on these results, 11.5% GA-R SL has potential as a botanical pesticide for aphid control. [Display omitted] • Binary combination of two extracts has synergistic effect. • 11.5% GA-R SL has remarkable control effect against aphids. • 11.5% GA-R SL: a potential environmentally friendly insecticide to control aphids. [ABSTRACT FROM AUTHOR]

Rotenone is a classic inhibitor of Complex I of the electron transport chain which is common to all life. Algae are known to be rotenone-insensitive because in addition to Complex I they have alternative pathways for the oxidation of NADH 2 . It is this differential sensitivity to rotenone that can be exploited to reduce many types of predators while not affecting biodiesel-producing algae. A universal tool like rotenone is needed to reduce predation in open ponds as predation is well known to limit cultivation to a few weeks in the warmer months. In this study, we tested the effect of rotenone on the mortality and reproduction of two marine algae strains, Nannochloropsis oculata and Tetraselmis suecica , and two marine rotifer strains, Brachionus manjavacas and Brachionus rotundiformis . The LC 50 s for the two rotifers ranged from 0.18 to 0.35 μM while N . oculata was unaffected to at least 7.6 μM. Rotifer reproduction was reduced at rotenone concentrations lower than those that caused mortality. Rotenone applications to produce 1 million gallons of biodiesel in one year are estimated to cost $1684. This provides algae farmers an important and inexpensive tool to manage grazing predators in algae mass cultures and avoid pond crashes. [ABSTRACT FROM AUTHOR]

Summary Immunological mediators that originate outside the nervous system can affect neuronal health. However, their roles in neurodegeneration remain largely unknown. Here, we show that the p38MAPK-mediated immune pathway activated in intestinal cells of Caenorhabditis elegans upon mitochondrial dysfunction protects neurons in a cell-non-autonomous fashion. Specifically, mitochondrial complex I dysfunction induced by rotenone activates the p38MAPK/CREB/ATF-7-dependent innate immune response pathway in intestinal cells of C. elegans . Activation of p38MAPK in the gut is neuroprotective. Enhancing the p38MAPK-mediated immune pathway in intestinal cells alone suppresses rotenone-induced dopaminergic neuron loss, while downregulating it in the intestine exacerbates neurodegeneration. The p38MAPK/ATF-7 immune pathway modulates autophagy and requires autophagy and the PTEN-induced putative kinase PINK-1 for conferring neuroprotection. Thus, mitochondrial damage induces the clearance of mitochondria by the immune pathway, protecting the organism from the toxic effects of mitochondrial dysfunction. We propose that mitochondria are subject to constant surveillance by innate immune mechanisms. [ABSTRACT FROM AUTHOR]

Infestation of pests on the field crops has resulted losses on its productivity yearly. Moreover, over usage of pesticides has also affected consumer's health as pesticides residues are detected inside the post-harvested crops. Therefore, the aim of this study is to determine the accumulation of rotenone Derris sp. in leaves, stem and fruit of terong plant ( Solanum melongena ) through the degradation rate (k) and half-life (t 1/2 ) of sprayed rotenone extract. The sprayed rotenone was prepared by using an optimized binary solvent mixture of 95% (v/v) acetone and ionic liquid (1-butyl-3-methylimidazolium trifluoromethansulfonate [BMIM] [OTf] via normal soaking extraction method. The same extraction method was used on the plant parts by using only 95% (v/v) of acetone. Reverse-phase high performance liquid chromatography (RP-HPLC) was used in analysing rotenone and [BMIM][OTf] traces. The results indicate that the degradation rates of 20 ppm were (1.35 ± 0.02 day -1 for leaves; 1.89 ± 0.07 day -1 for fruit) faster than 1000 ppm of rotenone extract (0.24 ± 0.00 day -1 for leaves; 0.21 ± 0.01 day -1 for stem; 0.31 ± 0.01 day -1 for fruit) ( p <0.05) within 6 days of observation. Rotenone was identified to possess the half-life (t 1/2 ) in the range of 0.37 ± 0.01 day to 0.51 ± 0.01 day in the study of 20 ppm rotenone extract. In contrast, the half-life (t 1/2 ) for rotenone on 1000 ppm extract was in the range of 2.23 ± 0.05 days to 3.38 ± 0.10 days which was longer than 20 ppm extract ( p <0.05). In conclusion, rotenone extract is still considered safe and has the potential to be used as a bio-pesticide due to its shorter half-life (t 1/2 ) (less than 7 days at the highest concentration of 1000 ppm) than other commercial pesticides. [ABSTRACT FROM AUTHOR]

Recent improvements in hygiene and innovations in medical technology have dramatically extended the average lifespan of humans in developed countries. However, extension of lifespan does not correlate with increased healthspan. In this study, we examined the health benefits of mature silk worm larvae enriched with diverse functional materials. We found that Drosophila reared on food containing boiled and freeze-dried mature silk worm larval powder (BMSPF) showed a significantly increased healthspan with an extended lifespan compared to normal food (NF) flies. In addition, BMSPF flies showed a significantly increased resistance to rotenone induced Parkinson's disease symptoms compared with NF flies. The results from microarray gene profiling, quantitative real-time PCR (QRT-PCR), and odorant response assays suggested that BMSPF flies may have improved olfactory responses compared with NF flies. In addition, integrity of mitochondria was significantly enhanced in BMSPF flies. Taken together, our data suggest that BMSP can be used to extend healthspan and prevent onset and progression of PD symptoms induced in Drosophila . [ABSTRACT FROM AUTHOR]

Ghrelin is an endogenous ligand for the growth hormone secretagogue (GHS) receptor and has several important physiological functions. Recently, particular attention has been paid to its neuroprotective effect. Rotenone is used to investigate the pathogenesis of Parkinson's disease (PD) for its ability to inhibit mitochondrial complex I. The current study was carried out to investigate the neuroprotective effects of ghrelin against rotenone in MES 23.5 dopaminergic cells and explored the possible mechanisms underlying this protection. Our results showed that rotenone induced significant decrease in cell viability which was counteracted by ghrelin treatment. In addition, rotenone challenge reduced mitochondrial membrane potential, inhibited the activity of mitochondrial complex I and depressed cytochrome C release from mitochondria. This mitochondrial dysfunction was reversed by ghrelin treatment. Furthermore, our results demonstrated that ghrelin protected MES23.5 cells against rotenone-induced apoptosis by inhibiting activation of caspase-3. Overall, our findings showed ghrelin provided protective effects on MES23.5 dopaminergic cells against rotenone via restoring mitochondrial dysfunction and inhibiting mitochondrial dependent apoptosis. [ABSTRACT FROM AUTHOR]

Objective Glucagon-like peptide-1 (GLP-1) is a potent satiating and incretin hormone released by enteroendocrine L-cells in response to eating. Dietary fat, in particular monounsaturated fatty acids, such as oleic acid (OA), potently stimulates GLP-1 secretion from L-cells. It is, however, unclear whether the intracellular metabolic handling of OA is involved in this effect. Methods First we determined the optimal medium for the bioenergetics measurements. Then we examined the effect of OA on the metabolism of the immortalized enteroendocrine GLUTag cell model and assessed GLP-1 release in parallel. We measured oxygen consumption rate and extracellular acidification rate in response to OA and to different metabolic inhibitors with the Seahorse extracellular flux analyzer. Results OA increased cellular respiration and potently stimulated GLP-1 release. The fatty acid oxidation inhibitor etomoxir did neither reduce OA-induced respiration nor affect the OA-induced GLP-1 release. In contrast, inhibition of the respiratory chain or of downstream steps of aerobic glycolysis reduced the OA-induced GLP-1 release, and an inhibition of the first step of glycolysis by addition of 2-deoxy- d -glucose even abolished it. Conclusion These findings indicate that an indirect stimulation of glycolysis is crucial for the OA-induced release of GLP-1. [ABSTRACT FROM AUTHOR]

Although algae-biofuels have many advantages including high areal productivity, algae can be preyed upon by amoeba, ciliates, and rotifers, particularly in open pond systems. Thus, these algal predators need to be controlled. In this study, Chlorella kessleri was used as the algae and the freshwater rotifer Brachionus calyciflorus as the predator. The effect of the pesticide, rotenone, was tested with the goal of totally inhibiting the rotifer while causing only minor inhibition to the alga. The rotenone 24-hr LC 50 for B. calyciflorus was 0.074 μM while C. kessleri growth was uninhibited at 0.8 μM. The rotenone EC 50 for population growth of the marine alga Tetraselmis suecica was 0.56 μM, in contrast to 0.13 and 0.26 μM for the marine rotifers Brachionus rotundiformis and Brachionus manjavacas , respectively. Rotifer reproduction was inhibited at even lower rotenone concentrations than those causing mortality. In co-culture, a rotenone concentration of 0.1 μM caused near complete B. calyciflorus mortality while leaving C. kessleri growth unaffected. Rotenone applications to produce 1 million gallons of biodiesel in one year are estimated to cost $842. This provides algae farmers an important and inexpensive tool to manage grazing predators in algae mass cultures and avoid pond crashes. [ABSTRACT FROM AUTHOR]

In healthy pancreatic islets, glucose-stimulated changes in intracellular calcium ([Ca 2+ ] i ) provide a reasonable reflection of the patterns and relative amounts of insulin secretion. We report that [Ca 2+ ] i in islets under stress, however, dissociates with insulin release in different ways for different stressors. Islets were exposed for 48 h to a variety of stressors: cytokines (low-grade inflammation), 28 mM glucose (28G, glucotoxicity), free fatty acids (FFAs, lipotoxicity), thapsigargin (ER stress), or rotenone (mitochondrial stress). We then measured [Ca 2+ ] i and insulin release in parallel studies. Islets exposed to all stressors except rotenone displayed significantly elevated [Ca 2+ ] i in low glucose, however, increased insulin secretion was only observed for 28G due to increased nifedipine-sensitive calcium-channel flux. Following 3–11 mM glucose stimulation, all stressors substantially reduced the peak glucose-stimulated [Ca 2+ ] i response (first phase). Thapsigargin and cytokines also substantially impacted aspects of calcium influx and ER calcium handling. Stressors did not significantly impact insulin secretion in 11 mM glucose for any stressor, although FFAs showed a borderline reduction, which contributed to a significant decrease in the stimulation index (11:3 mM glucose) observed for FFAs and also for 28G. We also clamped [Ca 2+ ] i using 30 mM KCl + 250 μM diazoxide to test the amplifying pathway. Only rotenone-treated islets showed a robust increase in 3–11 mM glucose-stimulated insulin secretion under clamped conditions, suggesting that low-level mitochondrial stress might activate the metabolic amplifying pathway. We conclude that different stressors dissociate [Ca 2+ ] i from insulin secretion differently: ER stressors (thapsigargin, cytokines) primarily affect [Ca 2+ ] i but not conventional insulin secretion and ‘metabolic’ stressors (FFAs, 28G, rotenone) impacted insulin secretion. [ABSTRACT FROM AUTHOR]

Dopaminergic neuronal loss in Parkinson's disease (PD) results from oxidative stress, neuroinflammation and excitotoxicity. Because erythropoietin (EPO) has been shown to have antioxidant, anti-inflammatory and neuroprotective effects in many previous studies, present study was designed to evaluate the effect of EPO on rotenone-induced dopaminergic neuronal loss. The rats in which PD was induced by stereotaxical infusion of rotenone showed increased MDA and TNF-alpha levels and decreased HVA levels. On the other hand, EPO treatment resulted in markedly decreased MDA and TNF-alpha levels and increased HVA levels. EPO treatment in rotenone-infusion group resulted in improvement of striatal neurodegeneration and a significant increase in decreased total number of neurons and immunohistochemical TH positive neurons. Results of the present study demonstrate the neuroprotective, anti-inflammatory and antioxidant effects of EPO in a rotenone-induced neurodegenerative animal model. [ABSTRACT FROM AUTHOR]

The mitochondrial respiratory chain of plants and some fungi contains multiple rotenone-insensitive NAD(P)H dehydrogenases, of which at least two are located on the outer surface of the inner membrane (i.e., external NADH and external NADPH dehydrogenases). Annotated sequences of the putative alternative NAD(P)H dehydrogenases of the protozoan Acanthamoeba castellanii demonstrated similarity to plant and fungal sequences. We also studied activity of these dehydrogenases in isolated A. castellanii mitochondria. External NADPH oxidation was observed for the first time in protist mitochondria. The coupling parameters were similar for external NADH oxidation and external NADPH oxidation, indicating similar efficiencies of ATP synthesis. Both external NADH oxidation and external NADPH oxidation had an optimal pH of 6.8 independent of relevant ubiquinol-oxidizing pathways, the cytochrome pathway or a GMP-stimulated alternative oxidase. The maximal oxidizing activity with external NADH was almost double that with external NADPH. However, a lower Michaelis constant ( K M ) value for external NADPH oxidation was observed compared to that for external NADH oxidation. Stimulation by Ca 2+ was approximately 10 times higher for external NADPH oxidation, while NADH dehydrogenase(s) appeared to be slightly dependent on Ca 2+ . Our results indicate that external NAD(P)H dehydrogenases similar to those in plant and fungal mitochondria function in mitochondria of A. castellanii . [ABSTRACT FROM AUTHOR]

Abstract: A study is presented on the regulation of alternative splicing (AS) of the Ndufb11 gene of complex I of the mitochondrial respiratory chain and the impact on this process of rotenone treatment in neuroblastoma cells. In physiological conditions the Ndufb11 gene produces at high level a short transcript isoform encoding for a 153 aa protein. This subunit is essential for the assembly of a functional and stable mammalian complex I. The gene produces also, at low level, a longer transcript isoform encoding for a 163 aa protein whose role is unknown. Evidence is presented here showing that the level of the two isoforms is regulated by three DGGGD ESS elements located in exon 2 which can bind the hnRNPH1 protein. In neuronal cells rotenone treatment affects the Ndufb11 alternative splicing pathway, with the increase of the 163/153 mRNAs ratio. This effect appears to be due to the down-regulation of the hnRNPH1 protein. Since rotenone induces apoptosis in neuronal cells, the post-transcriptional regulation of the Ndufb11 gene can be involved in the programmed cell death process. [Copyright &y& Elsevier]

Abstract: Even though rotenone has been used extensively in recent years to produce a model of Parkinson disease in rats, its systemic effects either on neurons apart from dopaminergic structures or non-neuronal tissues have not been elucidated well. In our present study, 30 adult Sprague-Dawley rats were divided into three even groups. A short-term rotenone-treated group received 10mg/kg b.w. rotenone daily for 7 days. The long-term rotenone-treated group received 3mg/kg b.w. rotenone daily for 30 days. The control group received vehicle only and were kept 5 rats each in parallel to both short- and long-term rotenone treated groups. It was found that short-term rotenone treatment produced marked vascular damages associated with ischemic neuronal degeneration particularly in the thalamus, cerebellum and nucleus dentatus. In long-term rotenone-treated group, vascular changes were less severe and neuronal degeneration was associated with mild microglial proliferation and astrocytosis. Non-neuronal pathology as the result of short-term rotenone exposure consisted of degeneration and necrosis of seminiferous tubular epithelia with formation of spermatide multinucleate giant cells. On the other hand, long-term rotenone treatment did not affect testicles and only caused sinusoidal dilatation in the liver, myocardial degeneration in the heart and interstitial hemorrhages in the kidneys and lungs. In conclusions, damage to blood vasculature by rotenone appeared mediating neuronal and non-neuronal pathology in Sprague-Dawley rats. This effect might provide new insights for ethiopathogenesis of neurodegenerative diseases and contributes to the understanding of hemorrhagic stroke. [Copyright &y& Elsevier]

Abstract: The South American fruit fly, Anastrepha fraterculus (Wied.), is one of the principal pests of fruit crops in Brazil. While organic farms use several compounds to control fruit flies, such as oils, plant extracts and soaps, there is little scientific evidence of their effectiveness. Our main goal was to evaluate the phytosanitary products used in organic orchards on A. fraterculus under laboratory conditions. Four multiples (0.25×, 0.5×, 1× and 2×) of the manufacturer-recommended concentrations of Rotenat CE® (extract of Derris spp. with rotenone 5%) (600ml 100l−1), Pironat® (pyroligneous extract) (250ml 100l−1), Biopirol 7M® (pyroligneous extract) (200ml 100l−1), Organic neem® (neem oil 80%) (500ml 100l−1), Natuneem® (neem oil – 1500ppm of azadirachtin) (500ml 100l−1) and lime sulfur (20% S+9% Ca) (5000ml 100l−1) were tested on A. fraterculus via ingestion and direct contact, topical application and residual application. We subsequently tested deterrence effects of the same products on oviposition. Organic Neem®, Natuneem®, lime sulfur, Pironat®, and Biopirol 7M® showed no insecticidal effect on the South American fruit fly. Only Rotenat CE® (1200ml 100l−1) showed an effect (71.6% mortality) following ingestion/contact. Lime sulfur, Pironat® and Biopirol 7M® did not prevent oviposition of A. fraterculus on artificial fruits. [Copyright &y& Elsevier]

Abstract: To study the role of mitochondrial Ca2+ clearance in stimulated cells, changes in free Ca2+ concentration in the cytosol, [Ca2+]c and that in mitochondria, [Ca2+]m along with secretory responses were observed using chromaffin cells co-loaded with Fura-2 and Rhod-2 in the perfused rat adrenal medulla. When the cells were stimulated with 40mM K+ in the perfusate, the duration of [Ca2+]m response markedly increased with prolongation of the stimulation period, exhibiting a mean half-decay time of 21min with 30s stimulation, whereas its amplitude was not altered with stimulations of 10–30s. A computer simulation analysis showed that such a mode of [Ca2+]m response can be produced if excess Ca2+ taken up by mitochondria precipitates as calcium phosphate (Pi) salt. In the presence of 5μM rotenone plus 10μM oligomycin, a decrease in the duration of [Ca2+]m response and a slight but significant increase (24%) in the secretory response to 30s stimulation with 40mM K+ were observed. Simulation analyses suggested that this effect of rotenone may be due to reduction in mitochondrial Ca2+ uptake induced by rotenone-elicited partial depolarization of the mitochondrial membrane potential. In chromaffin cells transsynaptically stimulated through the splanchnic nerve, the intensity of NAD(P)H autofluorescence changed with time courses similar to those of [Ca2+]m responses. The temporal profiles of those two responses were prolonged in a similar manner by application of an inhibitor of mitochondrial Na+/Ca2+ exchanger, CGP37157. Thus, due to the unique Ca2+ buffering mechanism, [Ca2+]m responses associated with massive mitochondrial Ca2+ uptake may occur within a limited concentration range in which Ca2+-sensitive dehydrogenases are activated to control the mitochondrial redox state in stimulated chromaffin cells. [Copyright &y& Elsevier]

This study was designed to evaluate the effects of triacylglycerol (TG) on nitric oxide (NO) production, expression of endothelial (e) and inducible (i) nitric oxide synthase (NOS) and variables related to oxidative stress in rat isolated hepatocytes. Hepatocytes were isolated and exposed to TG in the form of a lipid emulsion (0.01-0.1% LE). Exposure to LE dose dependently decreased nitrite levels. Nitrite levels were inhibited 67% and intracellular reactive oxygen species (ROS) levels were increased 250% at 0.1% LE. The decline in nitrite levels was accompanied by 37 and 67% reductions in iNOS and eNOS expressions, respectively. To evaluate whether the increased oxidative stress inhibited NOS synthesis, cells were treated for 48 h with rotenone (a mitochondrial complex 1 inhibitor) or buthionine sulfoximine (a glutathione synthesis inhibitor). Both compounds elevated ROS production, which was followed by inhibition of nitrite production. To determine whether there is an association between LE-mediated ROS production and the inhibition of NO synthesis by the LE, hepatocytes were treated with antioxidants. N-Acetyl-L-cysteine (NAC), ascorbate, and resveratrol attenuated the reduction of nitrite levels due to LE alone. NAC inhibited the reductions in eNOS and iNOS transcription and protein levels. Nuclear factor-KB (NF-sB), one of the transcription factors involved in eNOS and iNOS transcriptional regulation, was decreased 15% in the nucleus by LE treatment. These results suggest that TG reduces nitrite production by elevating intracellular ROS levels (prolonged oxidative stress), and the downregulation of NOS enzymes may occur at least in part via the NFxB pathway. [ABSTRACT FROM AUTHOR]

Isolated rat enterocytes, both normal and those de-energized with rotenone, were used to study the energy dependence of membrane and intracellular intestinal riboflavin transport in vitro. Membrane and intracellular transport were investigated by using short (3 min) and long (20 min) incubation times, respectively. For both types of cells and incubation times, [3H]-riboflavin uptake presented a saturable component prevailing at physiologic intraluminal concentrations. At 3 min incubation, saturable [3H]-riboflavin transport was apparently an energy-independent process with high affinity and low capacity. Values of the saturable component and its apparent constants, Km and Jmax, did not differ in normal and de-energized enterocytes. At 20 min incubation, saturable [3H]-riboflavin transport was a strictly energy-dependent process in which values of the saturable component were significantly greater in normal than in de-energized enterocytes. Km values did not differ in the two types of cells and were unmodified over 3 min, whereas in normal enterocytes, Jmax at 20 min [6.25 +/- 0.2 pmol/(mg protein. 20 min)] was significantly greater than at 3 min [2.67 +/- 0.33 pmol/(mg protein. 3 min)] and compared with de-energized enterocytes at 20 min [2.54 +/- 0.16 pmol/(mg protein. 20 min)]. Both membrane and intracellular events were inhibited by unlabeled riboflavin and analogs, which are good substrates for flavokinase, thus demonstrating the paramount role of this enzyme in riboflavin intestinal transport. [ABSTRACT FROM AUTHOR]

Abstract: Rotenone is a pesticide and a piscicide derived from the derris root. The mechanism for the cytotoxicity is at mitochondrial level affecting cellular respiration. A suicide by rotenone poisoning in an adult is described. An innovative laboratory methodology was developed for the principal requirement of the Coroner to determine a positive or negative result to assist in the investigation of the death. The antemortem concentrations detected were 4.05 ng/ml [0.00405 ppm] in the blood and 0.55 ng/ml [0.00055 ppm] in the serum. Toxicity in human is rare and therefore the interpretation of the toxicology results is complicated by the unavailability of a data bank. The cause of death was attributed to rotenone toxicity based on the circumstantial evidence and expert pathological opinion on a balance of probability acceptable under the Coroners Act 1988 and Coroners Rules 1984 in England and Wales. The forensic clinicopathology of rotenone toxicity is discussed. [Copyright &y& Elsevier]

A 64-year-old woman presented with coma, seizure, and lactic acidosis after ingesting 80 yam bean seeds. This rotenone-containing seeds cause cellular asphyxia via blockage of the mitochondrial electron transport. Subsequent oxidative stress results in the formation of lipid peroxidation (LPO). Rotenone analysis via liquid chromatography mass spectrometry revealed the following: 31,590 ng/mL in cooked yam bean seed and 100 ng/mL in the blood. We attempted to use N-acetylcysteine to alleviate oxidative stress and documented the continuous decline in the plasma concentration of LPO. [ABSTRACT FROM AUTHOR]

Background: Centella asiatica (CA) is one of the most valuable herbal medicines widely being used for the treatment of various neurological ailments that are challenging for health-care providers and also is deemed to be safe and effective.Purpose: Monoamines (MAs) are neurotransmitters and neuromodulators that play a significant role in the neural communication, regulation of motor and cognitive functions in the brain. Neurodegeneration is associated with elevated levels of MAO-B that can lead to damaging reactive oxygen species (ROS) in the brain. The current study, evaluated the effects of asiaticoside-D (AD) from neuroprotective CA, on the levels and activities of monoamine oxidase A and B (MAO-A and B), in addition to the behavioral analysis.Methods: Qualitative and quantitative analyses of various solvent extracts of CA were performed. The extracts were screened for antioxidant potential using 1,1-diphenyl-2-picryl hydroxyl (DPPH), 2,2'-azinobis-3-ethylbenzothiozoline-6-sulfonic acid (ABTS), hydrogen peroxide (H2O2) radical, nitric oxide (NO) radical inhibition, lipid peroxidation (LPO) and ferric reducing antioxidant power (FRAP) assays. The purification of AD was done by column, thin layer and high-performance liquid chromatographies followed by structural elucidation using IR, HR-MS, 1H and 13C NMR spectra. Docking studies were performed to assess the impact of AD on MAO-A and B.In vivo, Lumbricus terrestris were exposed to 0.4 ppm rotenone (ROT) of medium for 7 days and were subjected to co-treatment along with 15 ppm of AD from CA. At the end of experiment period, the neuronal behavior of worms was assessed. Cerebral ganglions (CGs) were removed and the m-RNA levels of MAO-A and B were analyzed by Semi Q-PCR and their activities were also analyzed.Results: The ethanolic extracts exhibited higher antiradical activity against DPPH, ABTS, H2O2, LPO, FRAP, NO and vitamin C with EC50 value of 20.2, 20.9, 20.4, 22.0, 24.9, 28.1, 25.5 and 22.0 µg/ml respectively. Structural analysis by IR, HR-MS, 1H and 13C NMR spectrum have shown the structure of the isolated compound as (2α, 3β)-2,3-dihydroxyurs-12-en-28-oicacid-O-α-L-rhamnopyranosyl-(1→4)-O-β-d-glucopyranosyl (1→6)-β-copyranosyl ester and was represented as AD. In silico interaction of AD with MAO-A and B residues Lys312 at distances of 1.84 Å and 2.44 Å respectively was found to exhibit high binding energy of -9.4 and 7.4 kcal. The neuronal behavior using L. terrestris showed significant improvement against (p < 0.001) ROT impaired behavior (group II) on AD supplementation (p < 0.05). Further, the m-RNA levels and activities of MAO-A and B which were significantly altered (p < 0.001) by ROT could be effectively maintained on AD supplementation.Conclusion: AD was found to exert its negative impact on the levels and activities of MAO-A and B in CGs of rotenone- induced changes in L. terrestris, the property which is considered to be crucial against ROT induced neurodegenerative pathology like -Parkinsonism. [ABSTRACT FROM AUTHOR]

Background & Aims: Previous studies of pancreatic acinar cells characterized the effects of Ca2+-releasing secretagogues and substances, inducing acute pancreatitis on mitochondrial Ca2+, transmembrane potential, and NAD(P)H, but dynamic measurements of the crucial intracellular adenosine triphosphate (ATP) levels have not been reported. Here we characterized the effects of these agents on ATP levels in the cytosol and mitochondria. Methods: ATP levels were monitored using cytosolic- or mitochondrial-targeted luciferases. Results: Inhibition of oxidative phosphorylation produced a substantial decrease in cytosolic ATP comparable to that induced by inhibition of glycolysis. Cholecystokinin-8 (CCK) increased cytosolic ATP in spite of accelerating ATP consumption. Acetylcholine, caerulein, and bombesin had similar effect. A bile acid, taurolithocholic acid 3-sulfate (TLC-S); a fatty acid, palmitoleic acid (POA); and palmitoleic acid ethyl ester (POAEE) reduced cytosolic ATP. The ATP decrease in response to these substances was observed in cells with intact or inhibited oxidative phosphorylation. TLC-S, POA, and POAEE reduced mitochondrial ATP, whereas physiological CCK increased mitochondrial ATP. Supramaximal CCK produced a biphasic response composed of a small initial decline followed by a stronger increase. Conclusions: Both glycolysis and oxidative phosphorylation make substantial contributions to ATP production in acinar cells. Ca2+-releasing secretagogues increased ATP level in the cytosol and mitochondria of intact isolated cells. TLC-S, POA, and POAEE reduced cytosolic and mitochondrial ATP. When cells rely on nonoxidative ATP production, secretagogues as well as TLC-S, POA, and POAEE all diminish cytosolic ATP levels. [Copyright &y& Elsevier]

La mort cellulaire au cours de l’ischémie-reperfusion cardiaque est associée à l’ouverture du pore de transition de perméabilité mitochondrial (mPTP). La cyclosporine A (CsA) limite l’étendue des dommages myocardiques en inhibant l’ouverture du mPTP. La production massive de radicaux libres de l’oxygène (ROS) pendant la reperfusion est soupçonnée être un facteur favorisant l’ouverture du mPTP. Nous avons réalisé sur des mitochondries isolées de cœur de rats sham des études doses-réponses de l’inhibiteur du complexe I (la roténone de 6,25nM à 6,25μm), ou de l’inhibiteur du complexe III (antimycine A de 2,5nM à 2,5μm) sur la capacité de rétention du calcium (CRC) et la production de ROS en présence ou absence de CsA (1μm). La CRC et la production de ROS ont été mesurées par spectrofluorimétrie en présence de Calcium Green ou d’Amplex Red respectivement. La roténone n’a pas d’effet sur la CRC (853±62nmoles/mg de prot) et la CsA augmente le CRC à 1405±89nmoles/mg de prot. La combinaison des deux potentialise l’effet de la CsA de 154±9 %. L’antimycine A diminue la CRC à partir de 25nM, la CsA n’antagonise pas cet effet. La production de ROS par les mitochondries est de 65±9pmol H2O2/min/mg prot. En présence de CsA, cette production diminue à 49±6pmol/min/mg prot. Quelque soit la dose utilisée de roténone, elle diminue cette production en présence ou absence de CsA. L’antimycine A augmente la production de ROS à partir de la concentration de 25nM en présence ou absence de CsA. En conclusion, les inhibiteurs de la chaine respiratoire modifient l’ouverture du mPTP et la production de ROS. Ces résultats sont en faveur du rôle délétère des ROS sur le mPTP et indiquent que le complexe I participe à la formation du mPTP. [Copyright &y& Elsevier]