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Highlights • MiR-142 levels were significantly increased in the amygdala of rats subjected to SPS. • Npas4 was identified as a direct target of miR-142. • Activation of miR-142 reduced the expression of Npas4 and BDNF. • Administration of LV-anti-miR-142 into amygdalae abolished the behavioral responses caused by SPS. Abstract Posttraumatic stress disorder (PTSD) is a prevalent mental disorder that is classified as a trauma- and stressor-related disorder. While numerous epigenetic factors are related to the risk for PTSD, the precise mechanisms underlying this disorder remain unclear. However, accumulating evidence has demonstrated that dysregulation of microRNAs is involved in stress-related psychiatric disorders, resulting in anxiety-like behavior, memory-related deficits and aberrant neuronal plasticity. Here, rats exposed to single prolonged stress showed increased microRNA-142-5p levels in the amygdala and a concurrent reduction in the levels of its predicted target Npas4, an activity-regulated transcription factor, which was implicated in stress-related psychopathologies. In addition, the inhibition of microRNA-142 following exposure to single prolonged stress exhibited decreased anxiety-like behaviors and memory deficits, as well as increased expression of Npas4 and BDNF. Furthermore, a dual-luciferase reporter assay indicated that Npas4 was a direct downstream target of miR-142. Taken together, these data suggest that miR-142 may play a key role in the pathogenesis of stress-related psychiatric disorders. [ABSTRACT FROM AUTHOR]

Among learning and memory processes, fear memories are crucial in some psychiatric disorders like post-traumatic stress disorder (PTSD). Accumulating evidence shows that the sigma-1 receptor (Sig-1R) has comprehensive involvement in cognitive impairment and neuroprotective effects. It has also been reported that BDNF appears to enhance extinction of fear in anxiety disorders via the MAPK signaling cascade. However, it remains unclear whether BDNF-TrkB-MAPK pathway may be mechanistically involved in the therapeutic effect of sigma-1 receptor in the development of PTSD. To address this question, rats were subjected to a classical single-prolonged stress procedure (SPS) and kept undisturbed for 7 days. After that, rats were re-stressed by re-exposure to the forced swim component of SPS (RSPS). Behavior tests were subsequently performed to assess anxiety and cognitive impairments. Furthermore, we analyzed the expression of BDNF and the phosphorylation of TrkB and three MAPK pathways, namely, the ERK, JNK and p38. We found that the levels of BDNF and p-TrkB were increased following the RSPS procedure, which were reversed by the administration of PRE-084. Meanwhile, among the three MAPK signaling pathways, only the p-ERK expression was increased following the RSPS procedure. Collectively, our results indicate that BDNF-TrkB-ERK signaling pathway may be involved in the activation of sigma-1 receptor to yield therapeutic benefits for PTSD. [ABSTRACT FROM AUTHOR]

Hormesis refers to the phenomenon that an exposure or repeated exposures of a toxin can elicit adaptive changes within the organism to resist to higher doses of toxin with reduced harm. Skeletal muscle shows considerable plasticity and adaptions in response to a single bout of acute exercise or chronic training, especially in antioxidant defense capacity and metabolic functions mainly due to remodeling of mitochondria. It has thus been hypothesized that contraction-induced production of reactive oxygen species (ROS) may stimulate the hormesis-like adaptations. Furthermore, there has been considerable evidence that select ROS such as hydrogen peroxide and nitric oxide, or even oxidatively degraded macromolecules, may serve as signaling molecules to stimulate such hermetic adaptations due to the activation of redox-sensitive signaling pathways. Recent research has highlighted the important role of nuclear factor (NF) κB, mitogen-activated protein kinase (MAPK), and peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α), along with other newly discovered signaling pathways, in some of the most vital biological functions such as mitochondrial biogenesis, antioxidant defense, inflammation, protein turnover, apoptosis, and autophagy. The inability of the cell to maintain proper redox signaling underlies mechanisms of biological aging, during which inflammatory and catabolic pathways prevail. Research evidence and mechanisms connecting exercise-induced hormesis and redox signaling are reviewed. [ABSTRACT FROM AUTHOR]

Loss of mitochondrial structural and functional integrity plays a critical role in the pathogenesis of muscle disuse atrophy. Peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) has been suggested to modulate autophagy–lysosome pathway (mitophagy) during muscle atrophy, but clear evidence is still lacking. In the current study, we tested the hypothesis that overexpression of PGC-1α via in vivo transfection would ameliorate mitophagy in mouse tibialis anterior muscle subjected to two weeks of immobilization (IM), followed by remobilization (RM). While mitochondrial biogenesis and antioxidant enzymes are decreased, all autophagic and mitophagic protein markers such as Beclin-1, Bnip3, PINK1, parkin, Mul1 and the LC3II/LC3I ratio were increased in IM–RM muscle together with activation of FoxO pathway. Overexpression of PGC-1α significantly increased mitochondrial DNA proliferation and oxidative enzyme activity, whereas it mitigated oxidative stress and mitochondrial ubiquination in IM–RM muscle. Protein contents of PINK1, parkin and Mul1 in mitochondria decreased by approximately 50% with PGC-1α treatment. Furthermore, PGC-1α overexpression suppressed FoxO1 and FoxO3 activation along with a decreased LC3II/LC3I ratio. Importantly, PGC-1α attenuated IM–RM-induced ubiquination and degradation of mitofusion protein Mfn2. Muscle apoptotic tendency, measured by Bax/Bcl2 ratio and caspase-3 activity, were elevated with IM–RM, but unaffected by PGC-1α. We conclude that overexpression of PGC-1α by in vivo transfection can inhibit activation of mitophagy pathway in the atrophying muscle caused by immobilization. [ABSTRACT FROM AUTHOR]

Quercetin, one of the most abundant dietary flavonoids, is reported to have protective function against various hepatotoxicant-induced hepatotoxicity. The present study aims to investigate the critical role of the nuclear factor erythroid 2-related factor 2 (Nrf2) antioxidative signaling pathway in the protection of quercetin against hepatotoxicity. Quercetin prevented the cytotoxicity induced by a variety of hepatotoxicants including clivorine (Cliv), acetaminophen (APAP), ethanol, carbon tetrachloride (CCl 4 ), and toosendanin (TSN) in human normal liver L-02 cells. Quercetin induced the nuclear translocation of Nrf2, along with the increased expression of the antioxidant responsive element (ARE)-dependent genes like catalytic or modify subunit of glutamate-cysteine ligase (GCLC/GCLM), and heme oxygenase-1 (HO-1). In addition, the HO-1 inhibitor zinc protoporphyrin (ZnPP) and the GCL inhibitor L -buthionine-( S , R )-sulfoximine (BSO) both reduced the hepatoprotection induced by quercetin. Quercetin had no effect on kelch-like ECH-associated protein-1(Keap1) expression, but molecular docking results indicated the potential interaction of quercetin with the Nrf2-binding site in Keap1 protein. Quercetin increased the expression of p62, and p62 siRNA decreased quercetin-induced hepatoprotection. Quercetin induced the activation of c-Jun N-terminal kinase (JNK) in hepatocytes. JNK inhibitor SP600125 and JNK siRNA both reduced quercetin-induced hepatoprotection. SP600125 and JNK siRNA decreased the increased p62 expression induced by quercetin. In addition, SP600125 also decreased the increased mRNA and protein expression of GCLC, GCLM, and HO-1 induced by quercetin. Taken together, our present study demonstrates that quercetin prevents hepatotoxicity by inducing p62 expression, inhibiting the binding of Keap1 to Nrf2, and thus leading to the increased expression of antioxidative genes dependent on Nrf2. Meanwhile, our study indicates that JNK plays some regulation in this process. [ABSTRACT FROM AUTHOR]

Highlights: [•] We tested 60 Chinese elders with MCI. [•] This is a randomized clinical trial. [•] Handball training can improve cognitive ability in elderly with MCI. [ABSTRACT FROM AUTHOR]

Abstract: Antitumor activities of water extract (fraction A), ethanol extract (fraction B), ethyl acetate extract (fraction C), non-ethyl acetate extract (fraction D) and compound diosbulbin B isolated from Dioscorea bulbifera L. (DB) were investigated in vivo in this present study. The results showed that fractions B and C both decreased tumor weight in S180 and H22 tumor cells bearing mice, while fractions A and D had no such effect. Furthermore, fraction C altered the weight of spleen and thymus, and the amounts of total leukocytes, lymphocytes and neutrophils in tumor-bearing mice. Further results showed that compound diosbulbin B demonstrated anti-tumor effects in the dose-dependent manner at the dosage of 2 to 16mg/kg without significant toxicity in vivo. Furthermore, on the basis of chemical analysis of the above extracts by high-performance liquid chromatography (HPLC) with a diode array detector (DAD), diosbulbin B was found to be the major antitumor bioactive component of DB. These results suggest that DB has potential anti-tumor effects which may be related to influencing the immune system for the first time, and the compound diosbulbin B is the major antitumor component of DB. [Copyright &y& Elsevier]

Abstract: Ferulic acid ethyl ester (FAEE) and ferulic acid (FA) were fed to rats to determine in vivo efficacy in elevating selected phase II enzyme activities and antioxidant capacity. Male Sprague–Dawley rats were fed the AIN-93M control diet, or the control diet supplemented with 1% FA, 1% FAEE, or 0.1% FAEE for 2weeks. Quinone reductase (QR), glutathione-S-transferase (GST), thioredoxin reductase (TxR) activities, and oxidised and reduced glutathione were determined for brain, lung, liver, kidney, intestine and colon tissues. Both FA and FAEE (1%) supplementation increased QR and GST specific activities in kidney and colon tissues by 23–38% relative to the control diet. FAEE (1%) supplementation also induced QR specific activity, by 1.46- and 1.27-fold over the control diet, in intestinal and lung tissue of animals, whereas FA did not. No effect of diet was observed on liver cytochrome P450-1A1 activity. These results demonstrate that dietary FA and FAEE induce QR activity in the colon, small intestine, lung, and kidney, and improve glutathione antioxidant status in the colon and intestine. Therefore, dietary FA and FAEE may elevate defences to oxidative- and xenobiotic-induced stress in vivo. [ABSTRACT FROM AUTHOR]

Abstract: Isoline is a retronecine-type pyrrolizidine alkaloid (PA) isolated from the traditional Chinese medicinal herb Ligularia duciformis. The present investigation was carried out to evaluate isoline-induced oxidative injury in various important mouse organs. Various tissue samples were collected after mice were administrated with 100mg/kg isoline for 36h, and then lipid peroxidation (LPO) level, total antioxidant capacity, glutathione-S-transferase (GST), glutathione peroxidase (GPx) and catalase (CAT) activities were determined to evaluate the oxidative injury. Our results showed that the total antioxidant capacity of liver, brain and lung were all decreased after given isoline, and the LPO level was increased in liver and heart of isoline-treated mice. Further antioxidant-related enzyme activity assays showed that isoline (100mg/kg) decreased GPx activity in liver and heart, increased CAT activity in liver, brain and heart, and decreased the GST activity in lung. Taken together, our results demonstrate that isoline can induce different oxidative injury in various important mouse organs, and of which liver is the most sensitive organ. [Copyright &y& Elsevier]

Abstract: Clivorine is an otonecine-type pyrrolizidine alkaloid (PA) isolated from the Chinese medicinal plant Ligularia hodgsonii Hook., and our previous reports have shown its toxicity on human normal liver L-02 cells. It is generally believed that biotransformation of PAs to its metabolites is required for their toxicity; thus, there is nearly no report about the toxicity of clivorine on other non-hepatic cells in vitro. The aim of this study is to observe the toxicity of clivorine on the non-hepatic human embryonic kidney 293 (HEK293) cell that is of epithelial origin, and its primary mechanism. Our results showed that clivorine significantly reduced HEK293 cell viability, but there was no detectable apoptotic DNA ladder and cleaved fragments of caspase-3 and caspase-9 in clivorine-treated cells, which indicates the toxicity of clivorine is not due to inducing apoptosis. The results of western blot showed that clivorine induced sustained p38, c-Jun N-terminal kinase (JNK) and extracellular signal-related kinases (ERK1/2) phosphorylation in a concentration- and time-dependent manner, and the JNK inhibitor SP600125 significantly augmented the toxicity of clivorine. Our results suggest that clivorine itself has direct toxicity on HEK293 cells, and phosphorylated JNK may play some role in counteracting the toxicity of clivorine on HEK293 cells. [Copyright &y& Elsevier]

Abstract: Contraction-induced production of reactive oxygen species has been shown to cause oxidative stress to skeletal muscle. As an adaptive response, muscle antioxidant defense systems are upregulated in response to exercise. Nuclear factor κB and mitogen-activated protein kinase are two major oxidative-stress-sensitive signal transduction pathways that have been shown to activate the gene expression of a number of enzymes and proteins that play important roles in maintenance of intracellular oxidant–antioxidant homeostasis. This mini-review will discuss the main mechanisms and gene targets for these signaling pathways during exercise and the biological significance of the adaptation. [Copyright &y& Elsevier]

Abstract: Generation of reactive oxygen species (ROS) is a ubiquitous biological phenomenon in eukaryotic cell life. During the past two decades, much attention has been paid to the detrimental effects of ROS such as oxidative stress, pathogenesis and aging. However, there is now increasing evidence and recognition that ROS are not merely damaging agents inflicting random destruction to the cell structure and function, but useful signaling molecules to regulate growth, differentiation, proliferation, and apoptosis, at least within the physiological concentration. In skeletal muscle contractile activity has been shown to upregulate antioxidant defense systems and ROS has been postulated to be essential in this adaptation. Available research data suggest that nuclear factor (NF)κB and mitogen-activated protein kinase (MAPK) play a critical role in the relay of oxidative stress signals to gene expression apparatus in the myocytes under a variety of physiological and pathological conditions. This mini-review will discuss the main mechanisms and gene targets for these antioxidant signaling pathways during exercise, inflammation and aging. [Copyright &y& Elsevier]

Abstract: Clivorine, a pyrrolizidine alkaloid, is a potent toxic compound extracted from a Chinese medicinal plant Ligularia hodgsonii Hook. We have previously shown that clivorine inhibited human normal liver L-02 cells proliferation and induced p38 mitogen-activated protein kinase phosphorylation. The aim of this study is to further observe the mechanism of clivorine-inhibited L-02 cells growth. In this paper we show here that clivorine can induce apoptosis in L-02 cells, reduce the expression of p53 protein but has no effect on the expression of Bcl-2 protein, and clivorine also induces the cleavage of the poly(ADP-ribose) polymerase in L-02 cells. Our results suggest that the anti-proliferative function of clivorine in L-02 cells may be due to its inducing cell apoptosis, and clivorine-induced cell apoptosis is independent of p53 protein. [Copyright &y& Elsevier]

Clivorine, a pyrrolizidine alkaloid extracted from Chinese medicinal plant Ligularia hodgsonii Hook significantly inhibited human normal liver L-02 cells proliferation and decreased L-02 cells viability. The results of western blot showed that clivorine strongly evoked phosphorylation of p38 mitogen-activated protein (MAP) Kinase in L-02 cells, but had no effect on extracellular signal-related kinases MAP Kinase phosphorylation. Moreover, another pyrrolizidine alkaloid monocrotaline had no effect on phosphorylation of p38 MAP Kinase in L-02 cells. These studies document the effects of pyrrolizidine alkaloid clivorine on the MAPK cascade and on the growth of human normal liver L-02 cells for the first time, which may be a possible reason for the toxic effects observed in those plants containing pyrrolizidine alkaloids. [Copyright &y& Elsevier]

The present study examined the effect of glutathione (GSH) and glutathione ethyl ester (GSH-E) supplementation on GSH homeostasis and exercise-induced oxidative stress. Male Swiss-Webster mice were randomly divided into 4 groups: starved for 24 h and injected with GSH or GSH-E (6 mmol/kg body wt, i.p.) 1 h before exercise, starved for 24 h and injected with saline (S); and having free access to food and injected with saline (C). Half of each group of mice was killed either after an acute bout of exhaustive swimming (E) or after rest (R). Plasma GSH concentration was 100-160% (P < 0.05) higher in GSH mice vs. C or S mice at rest, whereas GSH-E injection had no effect. Plasma GSH was not affected by exercise in C or S mice, but was 44 and 34% lower (P < 0.05) in E vs. R mice with GSH or GSH-E injection, respectively. S, GSH- and GSH-E-treated mice had significantly lower liver GSH concentration and the GSH:glutathione disulfide (GSSG) ratio than C mice. Hepatic and renal GSH and the GSH:GSSG ratio were significantly lower in E vs. R mice in all groups. GSH-E-treated mice had a significantly smaller exercise-induced decrease in GSH vs. C, S, and GSH-treated mice and no difference in the GSH:GSSG ratio in the kidney. Activities of gamma-glutamylcysteine synthetase and gamma-glutamyltranspeptidase in the liver and kidney were not affected by either GSH treatment or exercise. GSH concentration and the GSH:GSSG ratio in quadriceps muscle were not different among C, S and GSH-treated mice, but significantly lower in GSH-E-treated mice (P < 0.05). Hepatic malondialdehyde (MDA) content was greater in exercised mice in all but GSH-E-treated groups. GSH and GSH-E increased MDA levels in the kidney of E vs. R mice, but attenuated exercise-induced lipid peroxidation in muscle. Swim endurance time was approximately 2 h longer in GSH (351 +/- 22 min) and GSH-E (348 +/- 27) than S mice (237 +/- 17). We conclude that 1) acute GSH and GSH-E supplementation at the given doses does not increase tissue GSH content or redox status; 2) both GSH and GSH-E improve endurance performance and prevent muscle lipid peroxidation during prolonged exercise; and 3) while both compounds may impose a metabolic and oxidative stress to the kidney, this side effect is smaller with GSH-E supplementation. [ABSTRACT FROM AUTHOR]

Presents a study which investigated the response of tissue glutathione (GSH) status to an acute bout of exhaustive exercise in unfed and refed rats. Dietary treatment; Glutathione, exercise and feeding status; Amino acid concentrations; Plasma insulin and glucagon concentration; Lipid peroxidation.

The maximal activity and mRNA abundance of hepatic fatty acid synthase (FAS) and other lipogenic enzymes were investigated in rats meal-fed either a high fructose (F) or a high cornstarch (C) diet. The diet contained 50% F or C (g/100 g), casein (20%), cornstarch (16.13%), corn oil (5%), minerals (5.37%), vitamins (1%) and Solka-floc (2%). Female Sprague-Dawley rats (n = 44) were randomly divided into C or F groups that were meal-fed for 3 h/d; each group was subdivided into exercise-trained (T) and untrained (U) groups. Treadmill training was performed 4 h after the initiation of the meal at 25 m/min, 10% grade for 2 h/d, 5 d/wk, for 10 wk. Rats were killed 9 h after the meal and 27 h after the last training session. F-fed rats had significantly higher activities of all lipogenic enzymes assayed and mRNA abundance of FAS and acetyl-coenzyme A carboxylase (ACC) than C rats (P < 0.05). Concentrations of plasma insulin and glucose and liver pyruvate were not altered by F feeding. Proportions of the fatty acids 18:2 and 20:4 were lower, whereas those of 16:0 and 16:1 were higher, in livers of F than of C rats (P < 0.05). Training decreased FAS activity by 50% (P < 0.05), without affecting FAS mRNA level in C rats; this down-regulation was absent in the F rats. ACC mRNA abundance tended to be lower in CT than in CU rats (P < 0.075). L-Type pyruvate kinase activity was lower in FT than in FU rats (P < 0.05), whereas other lipogenic enzyme activities did not differ between T and U rats of each diet group. We conclude that hepatic lipogenic enzyme induction by high carbohydrate meal feeding may be inhibited by exercise training and that a fructose-rich diet may attenuate this training-induced down-regulation. [ABSTRACT FROM AUTHOR]

As a candidate antitumor agent, diosbulbin B (DB) can induce serious liver toxicity and other adverse reactions. DB is mainly metabolized by CYP3A4 in vitro and in vivo , but the cytotoxicity and anti -tumor mechanisms of DB have yet to be clarified. This study aimed to determine whether the cytotoxicity and anti -tumor effects of DB are related to the metabolism-induced activation of CYP3A4 in various cell models, including CYP-free NIH3T3 cells, primary rat hepatocytes, HepG2 and L02 cells of high CYP3A4 expression and wild-type. Results showed that DB did not markedly decrease the viability of NIH3T3 cells. DB metabolites, obtained from the metabolism by mouse liver microsomes, did not elicit cytotoxicity on NIH3T3 cells either. By contrast, DB could induce significant cytotoxicity on primary rat hepatocytes. The DB induced cytotoxicity on HepG2 or L02 cells with high CYP3A4 expression were stronger than those on wild-type cells. As a metabolic biomarker, the metabolite conjugate (M31) of DB with GSH was detected in the incubation system. A higher amount of M31 was generated in the transfected HepG2 and L02 cells than in the wild-type cells at different time points. Ketoconazole, however, could restrain DB induced cytotoxicity on primary rat hepatocytes and in CYP3A4 transfected HepG2 and L02 cells. Therefore, the cytotoxicity of DB was closely related to CYP3A4-metabolized reactive DB metabolites. [ABSTRACT FROM AUTHOR]

Abstract: Pyrrolizidine alkaloids (PAs) are distributed in plants worldwide including medicinal herbs or teas. In the present study, we investigated the effects of isoline, which is a retronecine-type PA isolated from traditional Chinese medicinal herb Ligularia duciformis, on mouse liver proteins by using proteomic approaches. Firstly, our results showed that 110mg/kg isoline increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities in serum, and hepatic tissue pathological observation further confirmed isoline-induced liver injury. Proteomic analysis showed that the liver samples from mice of isoline group demonstrated about 13 differentially expressed proteins compared with normal group, and those proteins may be involved in isoline-induced liver injury in mice. Next, all these 13 protein spots were identified by MALDI-TOF-TOF MS or LTQ MS; and among them 9 differentially expressed proteins are involved in the process of oxidative stress or cellular energy metabolism. Further lipid peroxidation analysis and ATPase assay confirmed the existing of oxidative injury induced by isoline and consequent disruption of energy metabolism. Furthermore, an in silico drug target searching program INVDOCK identified 2 potential protein targets of isoline, and the results are in support of proteomic analysis. In summary, the possible signaling molecules related with isoline-induced liver injury were demonstrated in this study. [Copyright &y& Elsevier]

• Overexpression of miR-124 or inhibition of C1ql3 rescued learning and memory deficit in APP/PS1 mice. • C1ql3 was a potential target of miR-124 in the brain of APP/PS1 mice. • Overexpression of miR-124 or inhibition of C1ql3 alleviated cerebromicrovascular impairments. • Overexpression of miR-124 or inhibition of C1ql3 rescued breakdown of blood-brain barrier in the APP/PS1 mice. • Overexpression of miR-124 or inhibition of C1ql3 promoted angiogenesis and reduced Aβ deposition in the APP/PS1 mice. Many neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease, are associated with microvascular dysfunction, but the cellular and molecular mechanisms are poorly understood. Recently, microRNAs (miRNAs) have been suggested to be involved in the microvascular dysfunction and subsequent memory impairment. MicroRNA-124 (miR-124) is one of the most abundant miRNAs in the brain that is dysregulated in the hippocampus of AD animals. To explore the role of miR-124 in AD pathology, we employed the APP/PS1 transgenic mice and found downregulation of miR-124 and upregulation of complement C1q-like protein 3 (C1ql3) in the hippocampus and cerebral cortex. Downregulation of miR-124 expression resulted in Aβ deposition and a variety of cerebromicrovascular impairments, including the decline in microvascular density, reduced angiogenesis, accompanied by C1ql3 alteration. Treatment with lentivirus-mediated overexpression of miR-124 or the C1q inhibitor C1INH rescued breakdown of blood-brain barrier, promoted angiogenesis and reduced Aβ deposition, and finally alleviated learning and memory deficit in APP/PS1 mice. Moreover, we found that C1ql3, a component of the classical complement, might be a potential target of miR-124. These results suggested that miR-124 was involved in the angiogenesis and vascular integrity in the hippocampus and the cerebral cortex of the AD mice by regulating the classical complement C1ql3. [ABSTRACT FROM AUTHOR]

Abstract Mitochondrial dysfunction plays an important role in the etiology of age-related muscle atrophy known as sarcopenia. PGC-1α is positioned at the center of crosstalk in regulating mitochondrial quality control, but its role in mitophagy in aged skeletal muscle is currently unclear. The present study investigated the effects of aging and PGC-1α overexpression via in vivo DNA transfection on key mitophagy protein markers, as well as mitochondrial dynamics related proteins, metabolic function and antioxidant capacity in mouse muscle. C57BL/6J mice at the age of 2 mo (young, Y; N = 14) and 24 mo (old, O; N = 14) were transfected in vivo with either PGC-1α DNA (OE, N = 7) or GFP (N = 7) into the tibialis anterior (TA) muscle followed by electroporation. PINK1 and Parkin protein contents were 3.6 and 1.4-fold higher (P < 0.01), whereas mitochondrial ubiquitination (Ub) increased 1.5-fold (P < 0.05), in O vs. Y mice. PGC-1 OE suppressed PINK and Parkin protein levels by 50–60% (P < 0.01), and decreased Ub by 20% (P < 0.05) in old mice. Aging significantly increased the protein content of LC3II (30%, P < 0.05), p62 (42%, P < 0.05), RheB (5.5-fold, P < 0.01), Beclin-1 (3-fold, P < 0.01) and Mfn2 (~4-fold, P < 0.01) in the TA muscle. However, these age-related increases in mitophagy markers were attenuated by PGC-1α OE. Furthermore, aging dramatically increased Fis-1 protein content by 14-fold (P < 0.01), along with a severe reduction of citrate synthase activity (64%, P < 0.01) and cytochrome c oxidase subunit IV (COXIV) protein content (85%, P < 0.01). PGC-1α OE mitigated the age effects on Fis-1 and Drp-1 (P < 0.05). Moreover, PGC-1α OE enhanced mitochondrial oxidative function and antioxidant enzyme activities, and decreased lipid peroxidation and inner membrane damage found in old mice (P < 0.01). In summary, our data demonstrate that mitophagy protein expression in skeletal muscle was enhanced at old age driven possibly by increased mitochondrial dysfunction, damage, and fission. PGC-1α OE was effective in ameliorating mitochondrial deficits but did not restore muscle fiber atrophy. Graphical abstract fx1 Highlights • Aging upregulates mitophagy-related proteins in mouse skeletal muscle. • Overexpression of PGC-1α ameliorates mitophagic pathway and mitochondrial quality control in aged muscle. • Overexpression of PGC-1α did not protect against age-related loss of muscle mass and fiber size. [ABSTRACT FROM AUTHOR]

The Nrf2/Keap1 antioxidant system plays important roles in protecting against oxidative stress and toxic stimuli, which may vary in infants, elderly, and females. Aim The constitutive expression of the Nrf2 genes during development and aging in both sexes would help our understanding of the Nrf2/Keap1 pathway in toxicological studies. Main methods Sprague Dawley rat livers were collected at 11 age points from prenatal (−2 d), neonatal (1, 7, 14 and 21 d), at puberty (28 and 35 d), at adulthood (60 and 180 d), to aging (540 and 800 d) from both sexes. Total RNA and proteins were extracted for real-time RT-PCR and Western-blot analysis. Key findings The abundant mRNA expression was in the order of Nrf2, Gclm, Nqo1, Gclc, Ho-1, and Keap1. The expression of these genes except Gclc was high in fetal livers, decreased at birth, reached the first peak at 7 days of age, and gradually decreased to adult levels till 180 days of age. All these genes remained high at 540 days of age, but declined at 800 days of age, with more increases with Nqo1 and Ho-1. Females had lower fetal, neonatal, and aged levels than males. Protein expressions of Nrf2, Nqo1, Ho-1, GCLC and GCLM agree with mRNA analysis. Significance This study characterized the age- and sex-related changes of Nrf2-related gene/proteins in livers of rats, and higher expressions in newborns and aged rats could cope with increased oxidative stress in infants and elderly. [ABSTRACT FROM AUTHOR]

Avenanthramides (Avns), the polyphenol compounds found only in oats, have been shown to exhibit anti-inflammatory effects mainly by inhibiting nuclear factor (NF)-κB activation in select cell lines. However, the molecular mechanism by which Avns regulate the NF-κB pathway is still unclear. The purpose of this study was to investigate (1) the molecular mechanism by which three main fractions of Avns (AvnA, AvnB and AvnC) interact with IκB Kinase β (IKKβ); and (2) whether this interaction results in reduced inflammatory responses in skeletal muscle cells. The protein-ligand docking and molecular dynamics simulation studies suggest that Avns acted as an allosteric inhibitor for modulating IKKβ’s affinity for the NF-κB complex. Thus, Avns reduced IKKβ kinase activity in response to tert-butyl hydroperoxide (tBHP) stimulation and attenuated tBHP-induced TNFα and IL-1β mRNA expression. Furthermore, the three-fold increases in cyclooxygenase-2 (COX-2) protein and luciferase activity with tBHP treatment were reduced by 50% with Avns ( P < .01), along with decreased prostaglandin E2 levels ( P < .01). These data indicate that Avns are potent inhibitors of NFκB-mediated inflammatory response due to the downregulation of IKKβ activity in C2C12 cells. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is the most common and serious complication of diabetes mellitus (DM). The present study investigates the amelioration of ethanol extract of Dendrobium chrysotoxum Lindl (DC) on streptozotocin (STZ)-induced DR and its engaged mechanism. Retinal immunofluorescence staining with cluster of differentiation 31 (CD31) demonstrated that DC (30–300 mg/kg) decreased the increased retinal vessels in STZ-induced diabetic rats. Retinal histopathological observation also showed that retinal vessels were decreased in DC-treated diabetic rats. DC decreased the increased retinal mRNA expression of vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) in diabetic rats, and DC also decreased the elevated serum VEGF level. Immunohistochemical staining further evidenced that DC decreased VEGF and VEGFR2 expression in retinas. Retinal mRNA expression of matrix metalloproteinase (MMP) 2/9 was decreased in DC (300 mg/kg)-treated diabetic rats. Serum levels of MMP 2/9, basic fibroblast growth factor (bFGF), platelet-derived growth factor (PDGF) A/B, insulin-like growth factor 1 (IGF-1), interleukin 1β (IL-1β), and IL-6 were all decreased in DC-treated diabetic rats. In addition, DC decreased the increased phosphorylation of p65 and the increased expression of intercellular adhesion molecule-1 (ICAM-1). In conclusion, DC can alleviate retinal angiogenesis during the process of DR via inhibiting the expression of VEGF/VEGFR2, and some other pro-angiogenic factors such as MMP 2/9, PDGF A/B, bFGF, IGF-1. In addition, DC can also ameliorate retinal inflammation via inhibiting NFκB signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract: Aged skeletal muscle demonstrates declines in muscle mass and deterioration of mitochondrial content and function. Peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α) plays an important role in promoting muscle mitochondrial biogenesis in response to exercise training, but its role in senescent muscle is not clear. In the present study we hypothesize that a downregulation of the PGC-1α signaling pathway contributes to mitochondrial deterioration in aged muscle whereas endurance training ameliorates the deficits. Three groups of Fischer 344/BNF1 rats were used: young, sedentary (Y, 4months); old, sedentary (O, 22months); and old trained (OT, 22months), subjected to treadmill running at 17.5m/min, 10% grade for 45min/day, 5days/week for 12-weeks. PGC-1α mRNA and nuclear PGC-1α protein content in the soleus muscle were both decreased in O vs. Y rats, whereas OT rats showed a 2.3 and 1.8-fold higher PGC-1α content than O and Y rats, respectively (P<0.01). Mitochondrial transcription factor A (Tfam), cytochrome c (Cyt c) and mitochondrial (mt) DNA contents were significantly decreased in O vs. Y rats, but elevated by 2.2 (P<0.01), 1.4 (P<0.05) and 2.4-fold (P<0.01), respectively, in OT vs. O rats. In addition, Tfam and mtDNA showed 1.6 and 1.8-fold (P<0.01) higher levels, respectively, in OT vs. Y rats. These adaptations were accompanied by significant increases in the expression of the phosphorylated form of AMP-activated kinase (AMPK) (P<0.01), p38 mitogen-activated kinase (MAPK) (P<0.05) and silent mating type information regulator 2 homolog 1 (SIRT1) (P<0.01) in OT rats. Furthermore, OT rats showed great levels of phosphorylation in cAMP responsive element binding protein (p-CREB) and DNA binding compared to O and Y rats. These data indicate that endurance training can attenuate aging-associated decline in mitochondrial protein synthesis in skeletal muscle partly due to upregulation of PGC-1α signaling. [Copyright &y& Elsevier]

Abstract: The 3D heterometallic 3d–4f coordination polymer, [EuZn(gly)(ox)2(H2O)2]n, 1, (gly=glycinate, ox=oxalate), was the product of the hydrothermal synthesis of glycinate from the reaction of tetrazole-1-acetic acid, sodium oxalate, zinc and europium salts in the presence of a trace quantity of nitric acid. Coordination polymer 1 exhibits an unusual 3D heterometallic coordination framework that is built up by heterometallic dinuclear EuZn secondary building units and mixed ox and gly linkers in a uninodal 6-connected vme {33.43.58.6} net. The solid-state photoluminescence and lifetime characteristics of 1 reveal intense red luminescence. [Copyright &y& Elsevier]

Abstract: Three norclerodane diterpenoids, diosbulbins K–M, and one analogous enolglycoside, diosbulbinoside G, together with four norclerodane diterpenoids, diosbulbins B, E, F and G, were isolated from rhizomes of Dioscorea bulbifera. Their structures were established by spectroscopic and chemical methods, including 1H and 13C NMR, NOESY, HSQC, HMBC, and HRMS analyses. The relative configurations of diosbulbins K and L, and diosbulbin F were confirmed by X-ray crystallographic diffraction analysis, and the absolute stereochemistry of diosbulbin K was determined by a modified Mosher’s method. The 13C NMR spectroscopic data for diosbulbins E, F and G were also measured for the first time. The compounds did not show significant cytotoxic and anti-bacterial activities. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to investigate the changes in the gene expression of Mitofusion (Mfn) 1 and 2 and Fission 1 (Fis1) and mitochondrial energy metabolism in response to altered energy demand during prolonged exercise in rat skeletal muscle. Male Sprague–Dawley rats were subjected to an acute bout of treadmill running at various durations and killed immediately or during recovery. Mfn1/2 and Fis1 mRNA and protein contents, reactive oxygen species (ROS) generation, state 3 and state 4 respiration rates, trans-innermembrane potential and ATP synthase activity were measured in isolated muscle mitochondria. We found that (1) Mfn1/2 mRNA contents were progressively decreased during 150 min of exercise, along with decreased Mfn 1 protein levels. Fis1 mRNA and protein contents showed significant increases after 120–150 min of exercise. These changes persisted through the recovery period up to 24 h. (2) Mitochondrial ROS generation and state 4 respiration showed progressive increases up to 120 min, but dropped at 150 min of exercise. (3) State 3 respiration rate and respiratory control index were unchanged initially but decreased at 150 and 120 min of exercise, respectively, whereas ATP synthase activity was elevated at 45 min and returned to resting level thereafter. Our data suggested that the gene expression of mitochondrial fusion and fission proteins in skeletal muscle can respond rapidly to increased metabolic demand during prolonged exercise, which could significantly affect the efficiency of oxidative phosphorylation. [Copyright &y& Elsevier]

Abstract: A biological treatment with the integration of partial nitrification, anaerobic ammonium oxidation (Anammox) and heterotrophic denitrification was successfully developed in a SBR with periodical air supply to treat landfill leachate. An operating temperature of 30±1°C and a dissolved oxygen concentration within 1.0–1.5mg/L were maintained in the SBR. First, the mixture of Anammox biomass and aerobic activated sludge (80% w/w) were inoculated, and inorganic synthetic wastewater with progressively increased N-loading was added. The activities of maximum aerobic ammonium oxidizing and anaerobic ammonium oxidizing reached 0.79 and 0.18(kg –N/kgdw/day) after the inoculation lasting 86days, respectively. Secondly, an unexpected group of heterotrophic denitrifying bacteria was inoculated into the reactor along with the feeding of raw landfill leachate, and the final maximum activities of aerobic ammonium oxidizing, anaerobic ammonium oxidizing and denitrification reached 2.83 (kg –N/kgdw/day), 0.65 (kg –N/kgdw/day) and 0.11 (kg –N/kgdw/day), respectively. [Copyright &y& Elsevier]

Abstract: The peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α)-activated signal transduction pathway has previously been shown to stimulate mitochondrial biogenesis in skeletal muscle in response to endurance exercise. In vitro data indicate that PGC-1α signaling may be sensitive to reactive oxygen species (ROS) but its role in vivo is not clear. The objectives of this study were (1) to investigate whether the PGC-1α pathway could be activated by a single bout of anaerobic exercise in rats, wherein a major portion of ROS was generated via the cytosolic xanthine oxidase (XO), and (2) to examine whether allopurinol (ALP), a specific XO inhibitor, would attenuate PGC-1α expression and signaling owing to decreased ROS generation. Female Sprague–Dawley rats were randomly divided into three groups: (1) subjected to sprinting on a treadmill at 35 m/min, 15% grade, for 3 min followed by 3 min slow running at 15 m/min, 0% grade, repeated until exhaustion (88 ± 4 min; Exer; N = 9); (2) subjected to the same exercise protocol (88 ± 4 min) but injected with two doses of ALP (0.4 mmol/kg, ip) 24 and 1 h before the experiment (Exer+ ALP; N = 9); and (3) rested control (C; N = 9). Exercise increased XO activity and ROS generation in the Exer rat vastus lateralis muscle (P < 0.05), whereas the Exer+ ALP group displayed only 7% XO activity and similar ROS level compared with the C group. PGC-1α protein content showed a 5.6-fold increase (P < 0.01) in Exer vs C, along with a 200% (P < 0.01) increase in both nuclear respiratory factor (NRF)-1 and mitochondrial transcription factor A (Tfam) content. ALP treatment decreased PGC-1α, NRF-1, and Tfam levels by 45, 19, and 20% (P < 0.05), respectively. Exercise doubled the content of the phosphorylated cAMP-responsive element-binding protein in the Exer group (P < 0.01) and tripled phosphorylated p38 mitogen-activated protein kinase (P < 0.01), whereas these effects were reduced by 60 and 30% (P < 0.01, P < 0.05), respectively, in Exer+ ALP rats. Nuclear factor-κB binding and phospho-IκB content were also increased in Exer rats (P < 0.01) and these increases were abolished by ALP treatment. The data indicate that contraction-activated PGC-1α signaling pathways in skeletal muscle are redox sensitive and that nonmitochondrial ROS play an important role in stimulating mitochondrial biogenesis. [Copyright &y& Elsevier]

A diet high in saturated fat leads to skeletal muscle deteriorations including insulin resistance, mitochondrial dysfunction and muscle fiber atrophy. Consumption of long-chain polyunsaturated fatty acids and exercise have shown promise in ameliorating high-fat diet (HFD)-induced oxidative stress and inflammation. However, the impact of extra virgin olive oil (EVOO) on mitochondrial homeostasis in muscle is largely unknown. This study aimed to investigate whether 12 wks of EVOO feeding alone and in conjunction with endurance training could protect against metabolic and mitochondrial dysfunction rat muscle with HFD. Female Sprague-Dawley rats were divided into 4 groups fed a control diet (C), HFD, EVOO diet, and EVOO diet with training (EVOO+T). Mitochondrial enzyme activity and protein content decreased with HFD compared to C, but were restored with EVOO and EVOO+T. EVOO+T elevated muscle cytochrome c and PGC-1α levels. HFD increased muscle proteolytic markers and protein ubiquitination, whereas these effects were not seen in EVOO and EVOO+T. HFD suppressed mitochondrial fusion protein level while increasing fission protein levels, but were restored with EVOO and EVOO+T. Mitophagy marker PINK1 content decreased with HFD, but was unchanged in EVOO and EVOO+T. EVOO+T upregulated autophagy markers, along with decreased phosphorylated/dephosphorylated FoxO3 ratio. Antioxidants enzyme levels were upregulated by EVOO and EVOO+T, and EVOO+T reduced HFD-induced lipid peroxidation. In conclusion, HFD impaired muscle oxidative capacity, promoted protein ubiquitination and mitochondrial fission, and upregulated autophagy markers. Replacement of HFD with EVOO corrected the observed adverse effects, while exercise training in conjunction with EVOO provided additional protection to the muscle. [ABSTRACT FROM AUTHOR]

Abstract: Uncoupling protein-3 (UCP3) expression has been shown to increase dramatically in response to muscular contraction, but the physiological significance of UCP3 upregulation is still elusive. In this study, UCP3 mRNA and protein expression were investigated along with mitochondrial respiratory function, reactive oxygen species (ROS) generation, and antioxidant defense in rat skeletal muscle during and after an acute bout of prolonged exercise. UCP3 mRNA expression was elevated sharply at 45 min of exercise, reaching 7- to 8-fold above resting level at 150 min. The increase in UCP3 protein content showed a latent response but was elevated ∼1.9-fold at 120 min of exercise. Both UCP3 mRNA and UCP3 protein gradually returned to resting levels 24 h postexercise. Mitochondrial ROS production was progressively increased during exercise. However, ROS showed a dramatic drop at 150 min although their levels remained severalfold higher during the recovery. Mitochondrial State 4 respiration rate was increased by 46 and 58% (p <0.05) at 90 and 120 min, respectively, but returned to resting rate at 150 min, when State 3 respiration and respiratory control index (RCI) were suppressed. ADP-to-oxygen consumption (P/O) ratio and ATP synthase activity were lowered at 3 h postexercise, whereas proton motive force and mitochondrial malondialdehyde content were unchanged. Manganese superoxide dismutase gene expression was not affected by exercise except for an increase in mRNA abundance at 3 h postexercise. These data demonstrate that UCP3 expression in rat skeletal muscle can be rapidly upregulated during prolonged exercise, possibly owing to increased ROS generation. Increased UCP3 may partially alleviate the proton gradient across the inner membrane, thereby reducing further ROS production by the electron transport chain. However, prolonged exercise caused a decrease in energy coupling efficiency in muscle mitochondria revealed by an increased respiration rate due to proton leak (State 4/State 3 ratio) and decreased RCI. We thus propose that the compromise of the oxidative phosphorylation efficiency due to UCP3 upregulation may serve an antioxidant function to protect the muscle mitochondria from exercise-induced oxidative stress. [Copyright &y& Elsevier]

Abstract: The physiological significance of cardiac mitochondrial uncoupling protein 2 (UCP2)-mediated uncoupling respiration in exercise is unknown. In the current study, mitochondrial respiratory function, UCP2 mRNA level, UCP2-mediated respiration (UCR), and reactive oxygen species (ROS) generation, as well as manganese superoxide dismutase (MnSOD) activity were determined in rat heart with or without endurance training after an acute bout of exercise of different duration. In the untrained rats, state 4 respiration and UCR-independent respiration rates were progressively increased with exercise time and were 64 and 70% higher, respectively, than resting rate at 150 min, whereas UCR was elevated by 86% with no significant change in state 3 respiration. UCP2 mRNA level showed a 5- and 4-fold increase, respectively, after 45 and 90 min of exercise, but returned to resting level at 120 and 150 min. Mitochondrial ROS production and membrane potential (Δψ) increased progressively until 120 min, followed by a decrease to the resting level at 150 min. MnSOD mRNA abundance showed a 2-fold increase at 120 min but MnSOD activity did not change with exercise. Training significantly increased mitochondrial ATP synthetase activity, ADP to oxygen consumption (P/O) ratio, respiratory control ratio, and MnSOD activity, whereas exercise-induced state 4 respiration, UCR, ROS production, and Δψ were attenuated in the trained rats. We conclude that (1) UCP2 mRNA expression and activity in rat heart can be upregulated during prolonged exercise, which may reduce cross-membrane Δψ and thus ROS production; and (2) endurance training can blunt exercise-induced UCP2 and UCR, and improve mitochondrial efficiency of oxidative phosphorylation due to increased removal of ROS. [Copyright &y& Elsevier]

MicroRNA-142-5p (miR-142-5p) has been found to be dysregulated in several neurodegenerative disorders. However, little is known about the involvement of miR-142-5p in Alzheimer's disease (AD). Brain angiogenesis inhibitor 3 (BAI3), which belongs to the adhesion-G protein-coupled receptor subgroup, contributes to a variety of neuropsychiatric disorders. Despite its very high expression in neurons, the role of BAI3 in AD remains elusive, and its mechanism at the cellular and molecular levels needs to be further elucidated. The current study sought to investigate whether miR-142-5p influenced BAI3 expression and neuronal synaptotoxicity induced by Aβ, both in APP/PS1 transgenic mice and a cellular model of Alzheimer's disease. Altered expression of miR-142-5p was found in the hippocampus of AD mice. Inhibition of miR-142 could upregulate BAI3 expression, enhance neuronal viability and prevent neurons from undergoing apoptosis. In addition, the reduction of phosphorylation of Synapsin I and calcium/calmodulin-dependent protein kinase II (CaMKII), as well as the expression of PSD-95 in the hippocampus of APP/PS1 transgenic mice, were significantly restored by inhibiting miR-142. Meanwhile, the levels of Aβ 1-42 , β-APP, BACE-1 and PS-1 in cultured neurons were detected, and the effects of inhibiting miR-142 on spatial learning and memory were also observed. Interestingly, we found that BAI3, an important regulator of excitatory synapses, was a potential target gene of miR-142-5p. Collectively, our findings suggest that miR-142 inhibition can alleviate the impairment of spatial learning and memory, reduce the level of apoptosis, and upregulate the expression of pCaMKII and BAI3 in the hippocampus of APP/PS1 transgenic mice; thus, appropriate interference of miR-142 may provide a potential therapeutic approach to rescue cognitive dysfunction in AD patients. [ABSTRACT FROM AUTHOR]