Chrysanthemum morifolium Flower Extract Ameliorates Obesity-Induced Inflammation and Increases the Muscle Mitochondria Content and AMPK/SIRT1 Activities in Obese Rats.

Decreased energy expenditure and chronically positive energy balance contribute to the prevalence of obesity and associated metabolic dysfunctions, such as dyslipidemia, hepatic fat accumulation, inflammation, and muscle mitochondrial defects. We investigated the effects of Chrysanthemum morifolium Ramat flower extract (CE) on obesity-induced inflammation and muscle mitochondria changes. Sprague-Dawley rats were randomly divided into four groups and fed either a normal diet, 45% high-fat diet (HF), HF containing 0.2% CE, or 0.4% CE for 13 weeks. CE alleviated HF-increased adipose tissue mass and size, dyslipidemia, hepatic fat deposition, and systematic inflammation, and increased energy expenditure. CE significantly decreased gene expression involved in adipogenesis, pro-inflammation, and the M1 macrophage phenotype, as well as glycerol-3-phosphate dehydrogenase (GPDH) and nuclear factor-kappa B (NF-kB) activities in epididymal adipose tissue. Moreover, CE supplementation improved hepatic fat accumulation and modulated gene expression related to fat synthesis and oxidation with an increase in adenosine monophosphate-activated protein kinase (AMPK) activity in the liver. Furthermore, CE increased muscle mitochondrial size, mitochondrial DNA (mtDNA) content, and gene expression related to mitochondrial biogenesis and function, including sirtuin 1 (SIRT1), peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), and PGC-1α-target genes, along with AMPK-SIRT1 activities in the skeletal muscle. These results suggest that CE attenuates obesity-associated inflammation by modulating the muscle AMPK-SIRT1 pathway.

Citrus hassaku Extract Powder Increases Mitochondrial Content and Oxidative Muscle Fibers by Upregulation of PGC-1α in Skeletal Muscle.

Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is expressed in skeletal muscles and regulates systemic metabolism. Thus, nutraceuticals targeting skeletal muscle PGC-1α have attracted attention to modulate systemic metabolism. As auraptene contained in citrus fruits promotes lipid metabolism and improves mitochondrial respiration, it could increase mitochondrial function through PGC-1α. Therefore, we hypothesized that PGC-1α is activated by auraptene and investigated its effect using Citrus hassaku extract powder (CHEP) containing >80% of auraptene. C2C12 myotubes were incubated with vehicle or CHEP for 24 h; C57BL/6J mice were fed a control diet or a 0.25% (w/w) CHEP-containing diet for 5 weeks. PGC-1α protein level and mitochondrial content increased following CHEP treatment in cultured myotubes and skeletal muscles. In addition, the number of oxidative fibers increased in CHEP-fed mice. These findings suggest that CHEP-mediated PGC-1α upregulation induced mitochondrial biogenesis and fiber transformation to oxidative fibers. Furthermore, as CHEP increased the expression of the protein sirtuin 3 and of phosphorylated AMP-activated protein kinase (AMPK) and the transcriptional activity of PGC-1α, these molecules might be involved in CHEP-induced effects in skeletal muscles. Collectively, our findings indicate that CHEP mediates PGC-1α expression in skeletal muscles and may serve as a dietary supplement to prevent metabolic disorders.

Qiangji Jianli Decoction promotes mitochondrial biogenesis in skeletal muscle of myasthenia gravis rats via AMPK/PGC-1α signaling pathway.

The Qiangji Jianli Decoction (QJJLD) is an effective Chinese medicine formula for treating Myasthenia gravis (MG) in the clinic. QJJLD has been proven to regulate mitochondrial fusion and fission of skeletal muscle in myasthenia gravis. In this study, we investigated whether QJJLD plays a therapeutic role in regulating mitochondrial biogenesis in MG and explored the underlying mechanism. Rats were experimentally induced to establish autoimmune myasthenia gravis (EAMG) by subcutaneous immunization with R97-116 peptides. The treatment groups were administered three different dosages of QJJLD respectively. After the intervention of QJJLD, the pathological changes of gastrocnemius muscle in MG rats were significantly improved; SOD, GSH-Px, Na+-K+ ATPase and Ca2+-Mg2+ ATPase activities were increased; and MDA content was decreased in the gastrocnemius muscle. Moreover, AMPK, p38MAPK, PGC-1α, NRF-1, Tfam and COX IV mRNA and protein expression levels were also reversed by QJJLD. These results implied that QJJLD may provide a potential therapeutic strategy through promoting mitochondrial biogenesis to alleviate MG via activating the AMPK/PGC-1α signaling pathway.

Improved Calcium Homeostasis and Force by Selenium Treatment and Training in Aged Mouse Skeletal Muscle.

During aging reduction in muscle mass (sarcopenia) and decrease in physical activity lead to partial loss of muscle force and increased fatigability. Deficiency in the essential trace element selenium might augment these symptoms as it can cause muscle pain, fatigue, and proximal weakness. Average voluntary daily running, maximal twitch and tetanic force, and calcium release from the sarcoplasmic reticulum (SR) decreased while reactive oxygen species (ROS) production associated with tetanic contractions increased in aged - 22-month-old - as compared to young - 4-month-old - mice. These changes were accompanied by a decline in the ryanodine receptor type 1 (RyR1) and Selenoprotein N content and the increased amount of a degraded RyR1. Both lifelong training and selenium supplementation, but not the presence of an increased muscle mass at young age, were able to compensate for the reduction in muscle force and SR calcium release with age. Selenium supplementation was also able to significantly enhance the Selenoprotein N levels in aged mice. Our results describe, for the first time, the beneficial effects of selenium supplementation on calcium release from the SR and muscle force in old age while point out that increased muscle mass does not improve physical performance with aging.

Polyphenols and their potential role in preventing skeletal muscle atrophy.

Skeletal muscle atrophy is the consequence of various conditions, such as disuse, denervation, fasting, aging, and disease. Even if the underlying molecular mechanisms are still not fully understood, an elevated oxidative stress related to mitochondrial dysfunction has been proposed as one of the major contributors to skeletal muscle atrophy. Researchers have described various forms of nutritional supplementation to prevent oxidative stress-induced muscle wasting. Among a variety of nutrients, attention has also focused on polyphenols, a wide range of plant-based compounds with antioxidant and inflammatory properties, many of which have beneficial effects on human health and might retard skeletal muscle loss and function impairment. The purpose of this review is to describe polyphenol actions in skeletal muscle atrophy prevention. Published articles from the last 10 years were searched on PubMed and other databases. Polyphenols are important molecules that should be considered when discussing possible strategies against muscle atrophy. In particular, the collected studies describe, for each polyphenol subclass, the beneficial effect on muscle mass preservation in various skeletal muscle disorders. In these examples, the polyphenol compounds appear to mainly act by reversing mitochondrial dysfunction. Given that the current information on polyphenols is mostly restricted to basic studies, more comprehensive research and additional studies should be performed to clarify their mechanisms of action in improving skeletal muscle functions during atrophy.

Glycogen storage in a zebrafish Pompe disease model is reduced by 3-BrPA treatment.

Pompe disease (PD) is an autosomal recessive muscular disorder caused by deficiency of the glycogen hydrolytic enzyme acid α-glucosidase (GAA). The enzyme replacement therapy, currently the only available therapy for PD patients, is efficacious in improving cardiomyopathy in the infantile form, but not equally effective in the late onset cases with involvement of skeletal muscle. Correction of the skeletal muscle phenotype has indeed been challenging, probably due to concomitant dysfunctional autophagy. The increasing attention to the pathogenic mechanisms of PD and the search of new therapeutic strategies prompted us to generate and characterize a novel transient PD model, using zebrafish. Our model presented increased glycogen content, markedly altered motor behavior and increased lysosome content, in addition to altered expression of the autophagy-related transcripts and proteins Beclin1, p62 and Lc3b. Furthermore, the model was used to assess the beneficial effects of 3-bromopyruvic acid (3-BrPA). Treatment with 3-BrPA induced amelioration of the model phenotypes regarding glycogen storage, motility behavior and autophagy-related transcripts and proteins. Our zebrafish PD model recapitulates most of the defects observed in human patients, proving to be a powerful translational model. Moreover, 3-BrPA unveiled to be a promising compound for treatment of conditions with glycogen accumulation.

Impact of alpha-tocopherol deficiency and supplementation on sacrocaudalis and gluteal muscle fiber histopathology and morphology in horses.

BACKGROUND: A subset of horses deficient in alpha-tocopherol (α-TP) develop muscle atrophy and vitamin E-responsive myopathy (VEM) characterized by mitochondrial alterations in the sacrocaudalis dorsalis medialis muscle (SC). OBJECTIVES: To quantify muscle histopathologic abnormalities in subclinical α-TP deficient horses before and after α-TP supplementation and compare with retrospective (r)VEM cases. ANIMALS: Prospective study; 16 healthy α-TP-deficient Quarter Horses. Retrospective study; 10 retrospective vitamin E-responsive myopathy (rVEM) cases . METHODS: Blood, SC, and gluteus medius (GM) biopsy specimens were obtained before (day 0) and 56 days after 5000 IU/450 kg horse/day PO water dispersible liquid α-TP (n = 8) or control (n = 8). Muscle fiber morphology and mitochondrial alterations were compared in samples from days 0 and 56 and in rVEM cases. RESULTS: Mitochondrial alterations more common than our reference range (<2.5% affected fibers) were present in 3/8 control and 4/8 treatment horses on day 0 in SC but not in GM (mean, 2.2; range, 0%-10% of fibers). Supplementation with α-TP for 56 days did not change the percentage of fibers with mitochondrial alterations or anguloid atrophy, or fiber size in GM or SC. Clinical rVEM horses had significantly more mitochondrial alterations (rVEM SC, 13% ± 7%; GM, 3% ± 2%) and anguloid atrophy compared to subclinical day 0 horses. CONCLUSIONS AND CLINICAL IMPORTANCE: Clinically normal α-TP-deficient horses can have mitochondrial alterations in the SC that are less severe than in atrophied VEM cases and do not resolve after 56 days of α-TP supplementation. Preventing α-TP deficiency may be of long-term importance for mitochondrial viability.

Effects of intermittent dietary supplementation with conjugated linoleic acid and fish oil (EPA/DHA) on body metabolism and mitochondrial energetics in mice.

Understanding the mitochondrial processes that contribute to body energy metabolism may provide an attractive therapeutic target for obesity and co-morbidities. Here we investigated whether intermittent dietary supplementation with conjugated linoleic (CLA, 18:2n-6), docosahexaenoic (22:6n-3, DHA) and eicosapentaenoic (20:5n-3, EPA) acids, either alone or in combination, changes body metabolism associated with mitochondrial functions in the brain, liver, skeletal muscle and brown adipose tissue (BAT). Male C57Bl/6 mice were divided into groups: CLA (50% cis-9, trans-11; 50% trans-10, cis-12), EPA/DHA (64% EPA; 28% DHA), CLA plus EPA/DHA or control (linoleic acid). Each mouse received 3 g/kg b.w. of the stated oil by gavage on alternating days for 60 days. Dietary supplementation with CLA or EPA/DHA increased body VO2 consumption, VCO2 production and energy expenditure, being fish oil (FO) the most potent even in combination with CLA. Individually, both oils reduced mitochondrial density in BAT. CLA supplementation alone also a) elevated the expression of uncoupling proteins in soleus, liver and hippocampus and the uncoupling activity in the last two, ad this effect was associated with reduced hydrogen peroxide production in hippocampus; b) increased proteins related to mitochondrial fission in liver. EPA/DHA supplementation alone also a) induced mitochondrial biogenesis in liver, soleus and hippocampus associated with increased expression of PGC1-α; b) induced proteins related to mitochondrial fusion in the liver, and fission and fusion in the hippocampus. Therefore, this study shows changes on mitochondrial mechanisms induced by CLA and/or EPA/DHA that can be associated with elevated body energy expenditure.

Resveratrol Improves Muscle Atrophy by Modulating Mitochondrial Quality Control in STZ-Induced Diabetic Mice.

SCOPE: In this study, we aim to determine the effects of resveratrol (RSV) on muscle atrophy in streptozocin-induced diabetic mice and to explore mitochondrial quality control (MQC) as a possible mechanism. METHODS AND RESULTS: The experimental mice were fed either a control diet or an identical diet containing 0.04% RSV for 8 weeks. Examinations were subsequently carried out, including the effects of RSV on muscle atrophy and muscle function, as well as on the signaling pathways related to protein degradation and MQC processes. The results show that RSV supplementation improves muscle atrophy and muscle function, attenuates the increase in ubiquitin and muscle RING-finger protein-1 (MuRF-1), and simultaneously attenuates LC3-II and cleaved caspase-3 in the skeletal muscle of diabetic mice. Moreover, RSV treatment of diabetic mice results in an increase in mitochondrial biogenesis and inhibition of the activation of mitophagy in skeletal muscle. RSV also protects skeletal muscle against excess mitochondrial fusion and fission in the diabetic mice. CONCLUSION: The results suggest that RSV ameliorates diabetes-induced skeletal muscle atrophy by modulating MQC.

Buyang Huanwu Tang improves denervation-dependent muscle atrophy by increasing ANGPTL4, and increases NF-κB and MURF1 levels.

Denervated-dependent skeletal muscle atrophy (DSMA) is a disorder caused by the peripheral neuro­disconnection of skeletal muscle. The current study aimed to investigate the molecular mechanism and potential therapeutic strategies for the DSMA. A DSMA rat model was established. A lentiviral vector expressing small interfering RNA (siRNA) targeting angiopoietin­like protein 4 (ANGPTL4) was generated and injected into the rats that were also treated with Buyang Huanwu Tang (BYHWT). Reverse transcription­quantitative polymerase chain reaction was performed to examine ANGPTL4 mRNA expression in anterior cervical muscle samples. Western blot assay was used to evaluate ANGPTL4, nuclear factor­κB (NF­κB) and muscle RING­finger protein­1 (MURF1) expression. The ultrastructure of muscle tissues was viewed using transmission electron microscopy. The cell apoptosis in muscle tissues was detected using the terminal deoxynucleotidyl transferase dUTP nick end labeling. The results indicated that BYHWT treatment increased ANGPTL4 mRNA and protein levels in muscle tissues. The suppression of ANGPTL4 using siRNA significantly increased inflammatory cells compared with the control siRNA group. BYHWT protected the ultrastructure muscle tissues and inhibited cell apoptosis in the DSMA model. The protective effect of BYHWT protected may be mediated by increased expression of NF­κB p65 and MURF1. In conclusion, BYHWT may improve denervation­dependent muscle atrophy by increasing ANGPTL4 expression, involving NF­κB and MURF1 signaling.

Oral Supplementation of Melatonin Protects against Fibromyalgia-Related Skeletal Muscle Alterations in Reserpine-Induced Myalgia Rats.

Fibromyalgia is a chronic syndrome characterized by widespread musculoskeletal pain and an extensive array of other symptoms including disordered sleep, fatigue, depression and anxiety. Important factors involved in the pathogenic process of fibromyalgia are inflammation and oxidative stress, suggesting that ant-inflammatory and/or antioxidant supplementation might be effective in the management and modulation of this syndrome. Recent evidence suggests that melatonin may be suitable for this purpose due to its well known ant-inflammatory, antioxidant and analgesic effects. Thus, in the current study, the effects of the oral supplementation of melatonin against fibromyalgia-related skeletal muscle alterations were evaluated. In detail, 90 Sprague Dawley rats were randomly treated with reserpine, to reproduce the pathogenic process of fibromyalgia and thereafter they received melatonin. The animals treated with reserpine showed moderate alterations at hind limb skeletal muscles level and had difficulty in moving, together with significant morphological and ultrastructural alterations and expression of inflammatory and oxidative stress markers in the gastrocnemius muscle. Interestingly, melatonin, dose and/or time dependently, reduced the difficulties in spontaneous motor activity and the musculoskeletal morphostructural, inflammatory, and oxidative stress alterations. This study suggests that melatonin in vivo may be an effective tool in the management of fibromyalgia-related musculoskeletal morphofunctional damage.

Zebrafish exposure to environmentally relevant concentration of depleted uranium impairs progeny development at the molecular and histological levels.

Uranium is an actinide naturally found in the environment. Anthropogenic activities lead to the release of increasing amounts of uranium and depleted uranium (DU) in the environment, posing potential risks to aquatic organisms due to radiological and chemical toxicity of this radionucleide. Although environmental contaminations with high levels of uranium have already been observed, chronic exposures of non-human species to levels close to the environmental quality standards remain scarcely characterized. The present study focused on the identification of the molecular pathways impacted by a chronic exposure of zebrafish to 20 µg/L of DU during 10 days. The transcriptomic effects were evaluated by the use of the mRNAseq analysis in three organs of adult zebrafish, the brain the testis and the ovaries, and two developmental stages of the adult fish progeny, two-cells embryo and four-days larvae. The results highlight generic effects on the cell adhesion process, but also specific transcriptomic responses depending on the organ or the developmental stage investigated. The analysis of the transgenerational effects of DU-exposure on the four-day zebrafish larvae demonstrate an induction of genes involved in oxidative response (cat, mpx, sod1 and sod2), a decrease of expression of the two hatching enzymes (he1a and he1b), the deregulation of the expression of gene coding for the ATPase complex and the induction of cellular stress. Electron microscopy analysis of skeletal muscles on the four-days larvae highlights significant histological impacts on the ultrastructure of both the mitochondria and the myofibres. In addition, the comparison with the transcriptomic data obtained for the acetylcholine esterase mutant reveals the induction of protein-chaperons in the skeletal muscles of the progeny of fish chronically exposed to DU, pointing towards long lasting effects of this chemical in the muscles. The results presented in this study support the hypothesis that a chronic parental exposure to an environmentally relevant concentration of DU could impair the progeny development with significant effects observed both at the molecular level and on the histological ultrastructure of organs. This study provides a comprehensive transcriptomic dataset useful for ecotoxicological studies on other fish species at the molecular level. It also provides a key DU responsive gene, egr1, which may be a candidate biomarker for monitoring aquatic pollution by heavy metals.

Effect of propolis ethanol extract on myostatin gene expression and muscle morphometry of Nile tilapia in net cages.

Propolis can be used as growth enhancer due to its antimicrobial, antioxidant, and immune-stimulant properties, but its effects on morphometry and muscle gene expression are largely unknown. The present study evaluates the influence of propolis on muscle morphometry and myostatin gene expression in Nile tilapia (Oreochromis niloticus) bred in net cages. Reversed males (GIFT strain) with an initial weight of 170 ± 25 g were distributed in a (2 x 4) factorial scheme, with two diets (DPRO, commercial diet with 4% propolis ethanol extract and DCON, commercial diet without propolis, control) and four assessment periods (0, 35, 70, and 105 experimental days). Muscles were evaluated at each assessment period. Histomorphometric analysis classified the fiber diameters into four groups: <20 µm; 20-30 µm; 30-50 µm; and > 50 µm. RT-qPCR was performed to assess myostatin gene expression. Fibers < 20 µm diameter were more frequent in DPRO than in DCON at all times. Fiber percentages >30 µm (30-50 and > 50 µm) at 70 days were 25.39% and 40.07% for DPRO and DCON, respectively. There was greater myostatin gene expression at 105 days, averaging 1.93 and 1.89 for DCON and DPRO, respectively, with no significant difference in any of the analyzed periods. Propolis ethanol extract did not affect the diameter of muscle fibers or the gene expression of myostatin. Future studies should describe the mechanisms of natural products' effects on muscle growth and development since these factors are highly relevant for fish production performance.

Histomorphologic and ultrastructural recovery of myopathy in rats treated with low-level laser therapy.

The purpose of the present work was to study the effect of low-level laser therapy (LLLT): helium-neon (He-Ne) and gallium arsenide (Ga-As) laser on the histomorphology of muscle and mitochondria in experimental myopathy in rats. Thirty Suquía strain female rats were distributed in groups: (A) control (intact), (B) injured, (C) injured and treated with He-Ne laser, (D) injured and treated with Ga-As laser, (E) irradiated with He-Ne laser on the non-injured muscle, and (F) irradiated with Ga-As laser on the non-injured muscle. Myopathy was induced by injecting 0.05 mg/rat/day of adrenaline in the left gastrocnemius muscle at the same point on five consecutive days, in groups B, C, and D. LLLT was applied with 9.5 J cm-2 daily for seven consecutive days in groups C, D, E, and F. The muscles were examined with optic and electronic microscopy. The inflammation was classified as absent, mild, and intense and the degree of mitochondrial alteration was graded I, II, III, and IV. Categorical data were statistically analyzed by Chi-square and the Fisher-Irwin Bilateral test, setting significant difference at p < 0.05. The damage found in muscle and mitochondria histomorphology in animals with induced myopathy (B) was intense or severe inflammation with grade III or IV of mitochondrial alteration. They underwent significant regression (p < 0.001) compared with the groups treated with He-Ne (C) and Ga-As (D) laser, in which mild or moderate inflammation was seen and mitochondrial alteration grades I and II, recovering normal myofibrillar architecture. No differences were found between the effects caused by the two lasers, or between groups A, E, and F. Group A was found to be different from B, C, and D (p < 0.001). LLLT in experimental myopathy caused significant muscular and mitochondrial morphologic recovery.

[Changes of perimysial junctional plates induced by excessive eccentric training and the effects of acupuncture intervention].

This study aimed to investigate the effects of acupuncture intervention on excessive eccentric training-induced changes of perimysial junctional plates (PJPs) domain. Thirty healthy male Wistar rats were randomly assigned to 5 groups: control group, four-week training group, four-week training + 1-week recovery group and four-week training + 1-week acupuncture group. Rats were subjected to continuous excessive eccentric training for 4 weeks (incline -16°, speed 16-20 m/min, 60-90 min/d, 5 day per week), and then were subjected to one-week spontaneous recovery or one-week recovery with acupuncture intervention (a piece of filiform needle for 4 min every day). The PJPs domain changes were observed under transmission electron microscopy, and the perimysial collagen network structural changes were examined by scanning electron microscopy with or without a digestion technique (NaOH). The following results were obtained: (1) Compared with control group, PJPs domain of four-week training group showed excessive shortening of sarcomere (P < 0.001), serious damage of sarcomere structure, and altered mitochondria morphology in intermyofibria and subsarcolemma; 54% degradation of sarcolemma, and increased number of caveolae (P < 0.01); reduced number of PJPs (P < 0.001). (2) In comparison with four-week training group, PJPs domain was slightly changed in four-week training + 1-week recovery group, i.e., partial recovery of sarcomere length and structure (accounting for 85.23% of control group), and recovery of intermyofibrial and subsarcolemmal mitochondria morphology; decreased sarcolemmal degradation (P < 0.001), and increased number of caveolae (P < 0.05); increased PJPs number (P < 0.001). (3) PJPs domain changed in four-week training + 1-week acupuncture group compared with four-week training + 1-week recovery group, which were substantial recovery of sarcomere length (accounting for 94.51% of control group), increased subsarcolemmal mitochondrial fusion (P < 0.001), decreased caveolae number (P < 0.001), and decreased PJPs number (P < 0.001). The results indicated that excessive eccentric training resulted in excessively reduced number of PJPs with altered PJPs domain homeostasis, thus impeding the adaptability to eccentric training. After 1 week of natural recovery, the number of PJPs was excessively increased, hindering muscle damage repair. Acupuncture intervention helped to recover PJPs number and PJPs domain homeostasis, thus significantly relieving overuse injuries.

Dietary nitrate markedly improves voluntary running in mice.

Nitrate supplementation is shown to increase submaximal force in human and mouse skeletal muscles. In this study, we test the hypothesis that the increased submaximal force induced by nitrate supplementation reduces the effort of submaximal voluntary running, resulting in increased running speed and distance. C57Bl/6N male mice were fed nitrate in the drinking water and housed with or without access to an in-cage running wheel. Nitrate supplementation in sedentary mice had no effect on endurance in a treadmill test, nor did it enhance mitochondrial function. However, after three weeks with in-cage running wheel, mice fed nitrate ran on average 20% faster and 30% further than controls (p<0.01). Compared to running controls, this resulted in ~13% improved endurance on a subsequent treadmill test (p<0.05) and increased mitochondrial oxidative capacity, as judged from a mean increase in citrate synthase activity of 14% (p<0.05). After six weeks with nitrate, the mice were running 58% longer distances per night. When nitrate supplementation was removed from the diet, the running distance and speed decreased to the control level, despite the improved endurance achieved during nitrate supplementation. In conclusion, low-frequency force improvement due to nitrate supplementation facilitates submaximal exercise such as voluntary running.

Effects of dietary vitamin E deficiency on systematic pathological changes and oxidative stress in fish.

The aim of this study was to investigate the effects of dietary vitamin E deficiency on systematic pathological changes and oxidative stress in fish. A total of 320 healthy common carp (Cyprinus carpio) were randomized into four groups; the control group was fed a basal diet supplemented with 100 IUkg-1 of vitamin E, while the three experimental groups were fed the same basal diet with reduced vitamin E content (0, 25, or 50 IUkg-1). Findings showed that fish in the experimental groups mainly presented with sekoke disease, exophthalmia, leprnorthsis, and ascites. Histopathological and ultrastructural changes comprised nutritional myopathy with muscle fiber denaturation and necrosis, and multi-tissue organ swelling, degeneration, and necrosis. Compared with the control group, RBC count, hemoglobin content, vitamin E concentration, and superoxide dismutase activity were significantly lower in all three experimental groups. However, malondialdehyde content was considerably higher in experimental groups than in the control group. However, there was no difference in glutathione peroxidase activity among groups. In conclusion, dietary vitamin E deficiency (<100 IUkg-1) can cause severe injury and, in particular, oxidative damage in common carp. The oxidative damage might be a main influence caused by vitamin E deficiency in fish. These findings reveal the complete systematic pathological effect of vitamin E deficiency in common carp, which may be applicable to other fish and animals.

The influence of dietary fat source on liver and skeletal muscle mitochondrial modifications and lifespan changes in calorie-restricted mice.

The Membrane Theory of Aging proposes that lifespan is inversely related to the level of unsaturation in membrane phospholipids. Calorie restriction (CR) without malnutrition extends lifespan in many model organisms, which may be related to alterations in membrane phospholipids fatty acids. During the last few years our research focused on studying how altering the predominant fat source affects the outcome of CR in mice. We have established four dietary groups: one control group fed 95 % of a pre-determined ad libitum intake (in order to prevent obesity), and three CR groups fed 40 % less than ad libitum intake. Lipid source for the control and one of the CR groups was soybean oil (high in n-6 PUFA) whereas the two remaining CR groups were fed diets containing fish oil (high in n-3 PUFA), or lard (high in saturated and monounsaturated fatty acids). Dietary intervention periods ranged from 1 to 18 months. We performed a longitudinal lifespan study and a cross-sectional study set up to evaluate several mitochondrial parameters which included fatty acid composition, H(+) leak, activities of electron transport chain enzymes, ROS generation, lipid peroxidation, mitochondrial ultrastructure, and mitochondrial apoptotic signaling in liver and skeletal muscle. These approaches applied to different cohorts of mice have independently indicated that lard as a fat source often maximizes the effects of 40 % CR on mice. These effects could be due to significant increases of monounsaturated fatty acids levels, in accordance with the Membrane Theory of Aging.

Effect of Mailuoning injection on 8-iso-prostaglandin F2 alpha and superoxide dismutase in rabbits with extremity ischemia-reperfusion injury.

BACKGROUND: To date, there are no effective treatments for extremity ischemia-reperfusion (IR) injury. The objective of the present study was to explore the protective effect of Mailuoning on IR injury by investigating the plasma levels of 8-iso-prostaglandin F2 alpha (8-iso-PGF2α) and the activity of superoxide dismutase (SOD) in rabbits. MATERIALS AND METHODS: The experimental models of posterior limb IR injury were established in thirty rabbits that were divided into three groups: the sham, IR, and IR + Mailuoning groups. At the end of ischemia, Mailuoning was injected intravenously into the rabbits in the IR + Mailuoning group, and normal saline solution was administered to the rabbits in the sham and IR groups. Venous blood samples were collected to measure the levels of 8-iso-PGF2α and the activity of SOD in the plasma at the following time points: at the onset of ischemia, the end of ischemia, and 2, 4, 8, 12, and 24 h after reperfusion. The skeletal muscles were harvested to examine the ultrastructure. RESULTS: The levels of 8-iso-PGF2α increased significantly and SOD activity decreased in the IR group at every time point after reperfusion (P <0.01 or P <0.05). In contrast, the levels of 8-iso-PGF2α and SOD activity were not significantly different after reperfusion in the IR + Mailuoning group (P >0.05) but were significantly different compared with the IR group (P <0.01). Using electron microscopy, the skeletal muscle injury was shown to be milder in the IR+ Mailuoning group after reperfusion compared with the IR group. CONCLUSIONS: The Mailuoning is capable of decreasing the excessive production of 8-iso-PGF2α and protecting SOD activity, thereby exhibiting a protective effect on extremity IR injury.

Arsenic induces sustained impairment of skeletal muscle and muscle progenitor cell ultrastructure and bioenergetics.

Over 4 million individuals in the United States, and over 140 million individuals worldwide, are exposed daily to arsenic-contaminated drinking water. Human exposures can range from below the current limit of 10 µg/L to over 1mg/L, with 100 µg/L promoting disease in a large portion of those exposed. Although increased attention has recently been paid to myopathy following arsenic exposure, the pathogenic mechanisms underlying clinical symptoms remain poorly understood. This study tested the hypothesis that arsenic induces lasting muscle mitochondrial dysfunction and impairs metabolism. Compared to nonexposed controls, mice exposed to drinking water containing 100 µg/L arsenite for 5 weeks demonstrated impaired muscle function, mitochondrial myopathy, and altered oxygen consumption that were concomitant with increased mitochondrial fusion gene transcription. There were no differences in the levels of inorganic arsenic or its monomethyl and dimethyl metabolites between controls and exposed muscles, confirming that arsenic does not accumulate in muscle. Nevertheless, muscle progenitor cells isolated from exposed mice recapitulated the aberrant myofiber phenotype and were more resistant to oxidative stress, generated more reactive oxygen species, and displayed autophagic mitochondrial morphology, compared to cells isolated from nonexposed mice. These pathological changes from a possible maladaptive oxidative stress response provide insight into declines in muscle functioning caused by exposure to this common environmental contaminant.