Levels In Muscle Tissue Research Articles

Apoglobin Stability Is the Major Factor Governing both Cell-free and in Vivo Expression of Holomyoglobin

Expression levels in animal muscle tissues and in Escherichia coli vary widely for naturally occurring mammalian myoglobins (Mb). To explore this variation, we developed an in vitro transcription and wheat germ extract-based translation assay to examine quantitatively the factors that govern expression of holoMb. We constructed a library of naturally occurring Mbs from two terrestrial and four deep-diving aquatic mammals and three distal histidine mutants designed to enhance apoglobin stability but decrease hemin affinity. A strong linear correlation is observed between cell-free expression levels of holo-metMb variants and their corresponding apoglobin stabilities, which were measured independently by guanidine HCl-induced unfolding titrations using purified proteins. In contrast, there is little dependence of expression on hemin affinity. Our results confirm quantitatively that deep diving mammals have highly stable Mbs that express to higher levels in animal myocytes, E. coli, and the wheat germ cell-free system than Mbs from terrestrial mammals. Our theoretical analyses show that the rate of aggregation of unfolded apoMb is very large, and as a result, the key factor for high level expression of holoMb, and presumably other heme proteins, is an ultra high fraction of folded, native apoglobin that is capable of rapidly binding hemin. This fraction is determined by the overall equilibrium folding constant and not hemin affinity. These results also demonstrate that the cell-free transcription/translation system can be used as a high throughput platform to screen for apoglobin stability without the need to generate large amounts of protein for in vitro unfolding measurements.

Evaluation of the Postmortem Glucose and Glycogen Levels in Hepatic, Renal, Muscle, and Brain Tissues: Is It Possible to Estimate Postmortem Interval Using These Parameters?

The aim of our study was to investigate the postmortem levels of glucose and glycogen in hepatic, renal, muscle, and brain tissues and then examine the changes in those levels that could be useful for estimating postmortem interval. We established an animal model. Seventy female BALB/c albino mice were used in this study. After being sacrificed, the mice were randomly divided into six groups according to time elapsed since death (Group 1: 0h; Group 2: 12h; Group 3: 24h; Group 4: 36h; Group 5: 48h; and Group 6: 60h). Glucose levels were significantly different between groups for all tissues studied. Slope of the change per unit time was higher for the hepatic glucose levels. Based on these results, it is possible to estimate postmortem interval using postmortem glucose levels in hepatic tissue. Tissue-specific assessment may contribute valuable information to postmortem interval studies.

Discovery of 4-Amino-8-quinoline Carboxamides as Novel, Submicromolar Inhibitors of NAD-Hydrolyzing Enzyme CD38.

Starting from the micromolar 8-quinoline carboxamide high-throughput screening hit 1a, a systematic exploration of the structure-activity relationships (SAR) of the 4-, 6-, and 8-substituents of the quinoline ring resulted in the identification of approximately 10-100-fold more potent human CD38 inhibitors. Several of these molecules also exhibited pharmacokinetic parameters suitable for in vivo animal studies, including low clearances and decent oral bioavailability. Two of these CD38 inhibitors, 1ah and 1ai, were shown to elevate NAD tissue levels in liver and muscle in a diet-induced obese (DIO) C57BL/6 mouse model. These inhibitor tool compounds will enable further biological studies of the CD38 enzyme as well as the investigation of the therapeutic implications of NAD enhancement in disease models of abnormally low NAD.

Abstract 3527: OTX015, a novel BET-bromodomain (BET-BRD) inhibitor, displays antitumoral effects in orthotopic and heterotopic models of human glioblastoma

Abstract Background: BRD2 and BRD4, members of the BET family of bromodomains, were recently described to be significantly increased in glioblastoma multiforme (GBM), the most common primary adult brain cancer. OTX015 (OncoEthix SA, Switzerland), a novel BET-BRD2/3/4 inhibitor, is currently being evaluated in clinical Phase Ib studies in hematologic malignancies and solid tumors, including GBM. Here, we report the effects of OTX015 in vitro as a single agent and in combination with temozolomide (TMZ) in human U87MG cells, along with in vivo activity in heterotopic and orthotopic U87MG models. Material and Methods: GI50s were determined in U87MG cells after 72 h with OTX015 or JQ1 with MTT assays. Combination indexes of simultaneous and sequential schedules of OTX015 with TMZ were determined using Chou & Talalay analysis. For orthotopic in vivo experiments, 105 U87MG cells were injected in the frontal lobe of nude mice and 5 days later mice were randomized. For the xenograft model, 5.106 U87MG cells were injected into the right lateral flank and mice were randomized when tumors reached 100 mm3. Treatment groups (n = 6) were: vehicle PBS, OTX015 50 mg/kg/BID and 100 mg/kg/daily, or TMZ 100 mg/kg/daily (ip, days 6-10). Median survival was determined in the orthotopic model by the Kaplan-Meier method. Tumor volume was evaluated 3 times weekly in the flank model. An independent in vivo experiment was done for the evaluation of OTX015 levels in tumor and normal tissues, animals were sacrificed after 7 days of treatment at 50 mg/kg/BID, using ultra performance liquid chromatography with tandem mass spectrometry. Results: OTX015 displayed antiproliferative effects in U87MG cells with GI50 values of 0.9μM versus 2.1μM for JQ1. OTX015/TMZ combination studies revealed synergistic activity when TMZ was administered after OTX015. OTX015 significantly increased survival in mice bearing orthotopic U87MG cells, with median survival of 28 and 25 days for 50 and 100 mg/kg/daily OTX015, respectively vs 19.5 days in control mice. Furthermore, in the heterotopic model, OTX015 treatment at both doses, significantly decreased tumor growth at day 22. No major side effects were seen during in vivo OTX015 treatment. In orthotopic models, OTX015 plasmatic levels were 1365.3 (±481)ng/mL, while in tumor and peritumoral brain tissues OTX015 levels were 995.0(±549) and 62.97(±10.3)ng/g tissue, respectively. In the flank model, OTX015 tumor levels were about 1.2 times higher than in peripheral muscle tissue and plasma levels [848.1(±127)ng/mL] and about 7 times higher than in normal brain tissue. Conclusion: We demonstrated the passage of OTX015 across the blood-brain barrier, as well as preferential binding of OTX015 to tumor tissue. Oral OTX015 treatment significantly enhanced survival and decreased tumor growth in GBM xenograft models, highlighting the therapeutic potential of OTX015 in GBM patients. Citation Format: Lucile Astorgues-xerri, Caroline Berenger, Mylène Cayol, Mohamed Bekradda, Elodie Odore, Keyvan Rezai, Esteban Cvitkovic, Maria E. Riveiro, L'Houcine Ouafik. OTX015, a novel BET-bromodomain (BET-BRD) inhibitor, displays antitumoral effects in orthotopic and heterotopic models of human glioblastoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3527. doi:10.1158/1538-7445.AM2015-3527

Exceptional longevity and muscle and fitness related genotypes: a functional in vitro analysis and case-control association replication study with SNPs THRH rs7832552, IL6 rs1800795, and ACSL1 rs6552828.

There are several gene variants that are candidates to influence functional capacity in long-lived individuals. As such, their potential association with exceptional longevity (EL, i.e., reaching 100+ years) deserves analysis. Among them are rs7832552 in the thyrotropin-releasing hormone receptor (TRHR) gene, rs1800795 in the interleukin-6 (IL6) gene and rs6552828 in the coenzyme A synthetase long-chain 1 (ACSL1) gene. To gain insight into their functionality (which is yet unknown), here we determined for the first time luciferase gene reporter activity at the muscle tissue level in rs7832552 and rs6552828. We then compared allele/genotype frequencies of the 3 abovementioned variants among centenarians [n = 138, age range 100–111 years (114 women)] and healthy controls [n = 334, 20–50 years (141 women)] of the same ethnic and geographic origin (Spain). We also studied healthy centenarians [n = 79, 100–104 years (40 women)] and controls [n = 316, 27–81 years (156 women)] from Italy, and centenarians [n = 742, 100–116 years (623 women)] and healthy controls [n = 499, 23–59 years (356 women)] from Japan. The THRH rs7832552 T-allele and ACSL1 rs6552828 A-allele up-regulated luciferase activity compared to the C and G-allele, respectively (P = 0.001). Yet we found no significant association of EL with rs7832552, rs1800795 or rs6552828 in any of the 3 cohorts. Further research is needed with larger cohorts of centenarians of different origin as well as with younger old people.

Discovery, Synthesis, and Biological Evaluation of Thiazoloquin(az)olin(on)es as Potent CD38 Inhibitors.

A series of thiazoloquin(az)olinones were synthesized and found to have potent inhibitory activity against CD38. Several of these compounds were also shown to have good pharmacokinetic properties and demonstrated the ability to elevate NAD levels in plasma, liver, and muscle tissue. In particular, compound 78c was given to diet induced obese (DIO) C57Bl6 mice, elevating NAD > 5-fold in liver and >1.2-fold in muscle versus control animals at a 2 h time point. The compounds described herein possess the most potent CD38 inhibitory activity of any small molecules described in the literature to date. The inhibitors should allow for a more detailed assessment of how NAD elevation via CD38 inhibition affects physiology in NAD deficient states.

The traditional drug Gongjin-Dan ameliorates chronic fatigue in a forced-stress mouse exercise model

Ethnopharmacological relevanceGongjin-Dan is a representative traditional Oriental medicine herbal drug that has been used to treat chronic fatigue symptoms for several hundred years. We evaluated the anti-fatigue effects of Gongjin-Dan and the underlying mechanisms in a chronic forced exercise mouse model. Methods and materialsBalb/C male mice underwent an extreme treadmill-based running stress (1-h, 5 days/week), and daily oral administration of distilled water, Gongjin-Dan (100, 200, or 400mg/kg), or ascorbic acid (100mg/kg) for 28 days. The anti-fatigue effects of Gongjin-Dan were evaluated with behavioral tests (exercise tolerance and swimming tests), and the corresponding mechanisms were investigated based on oxidative stress and inflammatory cytokine and stress hormone levels in skeletal muscle, sera, and brain tissue. ResultsGongjin-Dan significantly increased exercise tolerance and latency times but reduced the number of electric shocks and immobilization time on the treadmill running and swimming tests, compared with the control group. Gongjin-Dan also significantly ameliorated alterations in oxidative stress-related biomarkers (reactive oxygen species and malondialdehyde), inflammatory cytokines (tumor necrosis factor-α, interleukin-1 beta, interleukin-6, and interferon-γ) and glycogen and l-lactate levels in skeletal muscle, compared with those in the control group. Moreover, Gongjin-Dan considerably normalized the forced running stress-induced changes in serum corticosterone and adrenaline levels, as well as brain serotonin level. These antioxidant and anti-stress effects of Gongjin-Dan were supported by the results of Western blotting (4-hydroxynonenal and heme oxygenase-1) and the gene expression levels (serotonin receptor and serotonin transporter). ConclusionThese results support the clinical relevance of Gongjin-Dan regarding anti-chronic fatigue properties. The underlying mechanisms involve attenuation of oxidative and inflammatory reactions in muscle and regulation of the stress response through the hypothalmo-pituitary-adrenal axis.

Current status, between-year comparisons and maternal transfer of organohalogenated compounds (OHCs) in Arctic char (Salvelinus alpinus) from Bjørnøya, Svalbard (Norway)

High levels of organohalogenated compounds (OHCs) have been found in Arctic char from Lake Ellasjøen at Bjørnøya (Svalbard, Norway) compared to char from other arctic lakes. The first aim of the study was to investigate the OHC status, contaminant profile, and partitioning of OHCs between muscle and ovary tissue in spawning female char from the high-polluted Lake Ellasjøen and the low-polluted Lake Laksvatn. The second aim was to investigate if OHC levels in muscle tissue have changed over time. Between-lake comparisons show that the muscle levels (lipid weight) of hexachlorobenzene (HCB), chlordanes (∑CHLs), mirex, dichlorodiphenyltrichloroethanes (∑DDTs) and polychlorinated biphenyls (∑PCBs) were up to 36 times higher in char from Ellasjøen than in Laksvatn, and confirm that the char from Ellasjøen are still heavily exposed compared to char from neighboring lake. A higher proportion of persistent OHCs were found in Ellasjøen compared to Laksvatn, while the proportion of the less persistent OHCs was highest in Laksvatn. A between-year comparison of OHC levels (i.e., HCB, DDTs, PCBs) in female and male char shows higher levels of HCB in female char from Ellasjøen in 2009/2012 compared to in 1999/2001. No other between-year differences in OHC levels were found. Due to small study groups, findings associated with between-year differences in OHC levels should be interpreted with caution. OHCs accumulate in the lipid rich ovaries of spawning females, resulting in up to six times higher levels of OHCs in ovaries compared to in muscle (wet weight). The toxic equivalent (TEQ)-value for the dioxin-like PCBs (PCB-105 and -118) in ovaries of the Ellasjøen char exceeded levels associated with increased egg mortality in rainbow trout (Oncorhynchus mykiss). Hence, we suggest that future studies should focus on the reproductive health and performance abilities of the high-exposed population of char inhabiting Lake Ellasjøen.

Effects of resveratrol on lipid metabolism in muscle and adipose tissues: A reevaluation in a pig model

The body fat-lowering effect and mechanisms of action of resveratrol (0, 300, 600 mg resveratrol/kg diet) was evaluated in a pig model. Resveratrol improved serum lipid profiles, and decreased visceral adipose tissue weight and serum leptin level. In adipose tissue, peroxisome proliferator activated receptor γ (PPARγ) and fatty acid synthase (FAS) mRNA levels, and FAS and lipoprotein lipase (LPL) activities were decreased by resveratrol, while hormone sensitive lipase (HSL), adipose triglyceride lipase (ATGL) and carnitine palmitoyl transferase-1(CPT-1) mRNA levels, and HSL and CPT-1 activities were increased. In muscle tissue, PPARγ, FAS, acetyl-CoA carboxylase (ACC) and LPL mRNA levels and FAS and ACC activities were decreased by resveratrol, while HSL mRNA levels and CPT-1 activity were increased. Moreover, compared with the control group, LPL activity was decreased, and CPT-1 mRNA levels and HSL activity were increased in the 600 mg resveratrol/kg diet group. This study provides the very first evidence in a pig model that resveratrol could improve serum lipid profiles and decrease body fat deposition, which might be mediated by a reduction in fatty acid uptake and de novo lipogenesis, as well as an increase in fat mobilization and fatty acid oxidation in muscle and adipose tissues.

SNP in pre-miR-1666 decreases mature miRNA expression and is associated with chicken performance.

Polymorphisms in miRNA genes could potentially alter various biological processes by influencing the processing and (or) target selection of miRNAs. The rs14120863 (C > G) mutation, which we characterized in a Gushi-Anka F2 resource population, resides in the precursor region of miR-1666. Association analysis with chicken carcass and growth traits showed that the SNP was significantly associated with carcass weight, evisceration weight, breast muscle weight, leg muscle weight, and body weight at 8 weeks of age, as well as some body size indexes including shank girth, chest breadth, breast bone length, and body slanting length, in the Gushi-Anka F2 resource population. Quantitative RT-PCR results showed that miR-1666 expression levels in muscle tissues differed within various genotypes. Experiment in DF1 cells further confirmed that the SNP in miR-1666 could significantly alter mature miRNA production. Subsequently, using dual-luciferase report assay, we verified that miR-1666 could perform its function through targeting of the CBFB gene. In conclusion, the SNP in the precursor of miR-1666 could significantly reduce mature miR-1666 production. It may further affect the function of miR-1666 through the target gene CBFB, hence it is associated with chicken growth traits.

Effects of acupotomylysis on basic fibroblast growth factor and CD34 levels in rabbits with third lumbar vertebral transverse foramen syndrome.

This study observed the local tissue homogenates in rabbits with third lumbar vertebral transverse foramen syndrome and explored the mechanism of acupotomylysis in local tissue revascularization. Thirty Japanese white rabbits were randomly divided into the following 5 groups of 6 rabbits each: normal, model, acupotomy, electroacupuncture (EA), and acupotomy-EA groups. All except the normal group were comprised of animal models of third lumbar vertebral transverse foramen syndrome prepared by embedding sponge in the left third lumbar transverse process. The rabbits in the acupotomy and EA groups underwent bilateral acupotomylysis intervention; those in the acupotomy-EA group underwent acupotomylysis and EA interventions. On the 28th day after modeling, the double-antibody ELISA was used to detect b-FGF and CD34 levels in the serum and homogenates of a muscle tissue sample from the left side of the third lumbar transverse process. The b-FGF levels in local muscle homogenates were significantly higher in the modeled rabbits than in the normal rabbits (P < 0.01), and the CD34 levels in the modeled group were significantly lower than in the normal group (P < 0.01). The b-FGF and CD34 levels in the EA, acutopomy, and acutopomy-EA groups were significantly lower than those in the modeled group (P < 0.01); the CD34 levels were significantly higher in the acupotomy-EA group than in the model group (P < 0.05); and the differences among the EA, acupotomy, and acupotomy-EA groups were not significant (P > 0.05). In conclusion, acupotomylysis regulates the levels of b-FGF and CD34 levels in serum and muscle tissue as well as local tissue revascularization.

VKORc1 Is Under-Expressed in Skeletal Muscle of Humans, Dogs and Mice: Potential Implications for Ectopic Coagulation Factor Expression in Pre-Clinical and Therapeutic Applications

Post-translational modifications of coagulation factors in the liver are essential for function. The vitamin K dependent coagulation proteins (VKCPs) require vitamin K to undergo gamma carboxylation of the glutamic residues in their Gla domain by gamma-glutamyl carboxylase [GGCX]. The vitamin K is then recycled by the action of epoxide reductase [VKORc1] and/or quinone reductase [NQO1]. The hemostatic importance of the vitamin K “cycle” is evidenced by patients who may suffer bleeding complications when anticoagulated with warfarin, which targets the vitamin K cycle. Moreover, the ability of a variety of VKCPs to secrete a biologically active product depends on the removal of their propeptide by the action of the intracellular endoprotease furin [FURIN gene]. Previous in vitro work on recombinant coagulation Factor IX, which is used for hemophilia B treatment, has connected these two processing steps by showing that endogenous VKORc1 as well as FURIN can be limiting factors in high-yield expression systems. In vivo, skeletal muscle (in contrast to liver) has been utilized to express low levels of coagulation Factor IX in the first hemophilia B gene therapy clinical trial. However, our experiments in mice demonstrated that the specific activity of muscle-synthesized Factor IX via gene transfer decreased at the high levels of FIX expression by a limited muscle area (Schuettrumpf J. et al., Blood 2005). These results suggest that in vitro and in vivo expression of biologically-active VKCPs outside the liver may be limited by the host cell post-translational modification machinery. Here, we performed a systematic study to determine the expression profiles of the vitamin K cycle and furin endoprotease genes in human liver and muscle, compared to the mouse. We also established these profiles in two hemophilic dogs, given the extensive use of this animal model in gene-based hemophilia therapies. RNA from liver and skeletal muscle was used as a template for reverse transcription and the subsequent relative quantification of the GGCX, VKORc1, NQO1, and FURIN genes by qPCR in each tissue using a housekeeping reporter gene. For this, a variety of housekeeping genes were investigated in all three species to identify ones with similar transcript levels in both liver and muscle tissue. We identified the housekeeping genes HPRT1, beta actin, and 18s rRNA as equivalently expressed in the liver and skeletal muscle of human, mouse, and dog, respectively. The relative mRNA transcript quantification of the vitamin K cycle genes in humans showed that the transcript levels of GGCX were similar in liver and muscle. In contrast, both VKORc1 and NQO1 were under-expressed in muscle vs. liver (69.5 ± 4.9% and 67.8 ± 12.5%, respectively, P<0.01). In the mouse, VKORc1 transcript levels in the muscle were reduced to 73.8 ± 9.9% vs. liver (P<0.05), while GGCX and NQO1 exhibited similar transcript levels in both tissues. In the dog, we observed a dramatic reduction in VKORc1 and GGCX transcript levels in the muscle vs. liver (11.8 ± 4.2% and 29.5 ± 15.8%, respectively, P<0.01). Surprisingly, NQO1 transcript levels were 253.8 ± 156.7% higher in muscle than liver (P<0.05). Lastly, in all three species tested, transcript levels for FURIN were similar in both muscle and liver. Our results indicate that VKORc1, a key enzyme in the vitamin K cycle, is consistently under-expressed in the skeletal muscle of humans as well as in mice and hemophilic dogs. In contrast, FURIN transcripts are similarly abundant in the liver and muscle of all three species tested. These suggest that the vitamin K cycle but not propeptide processing by furin can be a limiting factor in the secretion of biologically active muscle-expressed VKCPs. As a result, our observations provide (1) a plausible explanation for the inverse relationship between specific activity and Factor IX expression levels in mice following Factor IX gene transfer, and (2) further support for the mouse and dog as useful models for therapies that depend on the muscle-derived expression of VKCPs. DisclosuresNo relevant conflicts of interest to declare.

Liver ENPP1 protein increases with remission of type 2 diabetes after gastric bypass surgery.

BackgroundType 2 diabetes mellitus (T2DM) is a progressive disease resulting from increasing insulin resistance and reduced pancreatic β-cell insulin secretion. Ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) inhibits insulin signalling and may contribute to the pathogenesis of T2DM. Others have found elevated ENPP1 levels in muscle, fat, and skin tissues from insulin resistant individuals, but similar data on liver ENPP1 is lacking. The purpose of this study was to compare expression and protein concentrations of ENPP1 in liver between patients with and without T2DM.MethodsRoux-en-Y gastric bypass surgery (RYGB) results in remission of insulin resistance and T2DM thus presenting an opportunity to examine some critical aspects of these conditions. We measured liver ENPP1 gene and protein expression in individuals with or without T2DM at RYGB and on average 17 (±5.6) months later.ResultsWe found liver ENPP1 protein abundance was lower in individuals with T2DM than in those with normal glucose tolerance, and increased after RYGB surgery in those individuals who had remission of T2DM. ENPP1 positively correlated with insulin sensitivity at the liver (as measured by HOMA-IR), which is contrary to what others have reported in other insulin target tissues.ConclusionsLiver ENPP1 expression in T2DM is the reverse of that expected based on expression in other tissues and is likely due to the unique role the liver has in insulin clearance. The work presented here adds another dimension to the role of ENPP1, and supports the hypothesis that ENPP1 may act as a natural modulator of insulin signalling in the liver.Electronic supplementary materialThe online version of this article (doi:10.1186/s12876-014-0222-x) contains supplementary material, which is available to authorized users.

Associations between pig adiponectin (ADIPOQ) genotype and serum lipid levels are modulated by age-specific modifiers.

The adiponectin (ADIPOQ) locus is a positional and functional candidate gene for 2 porcine chromosome 13 (SSC13) QTL influencing cholesterol (CHOL) and low-density lipoprotein (LDL) concentrations in 190-d-old pigs. By sequencing 2.37 kb of the pig ADIPOQ cDNA, we have identified 1 c.*1512G>T 3' untranslated region polymorphism that has been genotyped in a Duroc pig commercial population with records for serum lipid levels at 45 and 190 d of age. Statistical analysis of the data have revealed significant associations between the ADIPOQ genotype and CHOL (P=0.0040) and LDL (P=0.0011) concentrations at 190 d but not at 45 d. In family 3, most of the SSC13 QTL effects on LDL levels at 190 d were explained by the ADIPOQ genotype. We also found an association with triglyceride levels at 45 d (P=0.0060) but not at 190 d. Measurement of allelic mRNA imbalance demonstrated that the G and T alleles are expressed at very similar levels in muscle and fat tissues, indicating that the c.*1512G>T polymorphism does not affect transcript abundance. As a whole, results obtained in the current work as well as previous data gathered in humans and pigs provide evidence that the magnitude of associations between blood lipid phenotypes and candidate loci genotypes may vary depending on the age of the individual, therefore suggesting the existence of dynamic genotype×environment interactions changing on a temporal scale.

Cortisol and Fatty Acid Contents in Hanwoo Meat Produced by Antibiotics-free Rearing System

This study was carried out to elucidate the effect of antibiotic-free rearing system(ARS) on cortisol level, stress hormone, and fatty acid content in the edible muscle tissues, that were of M. longissimus in Hanwoo. These cattle were reared in two different systems including antibiotic-free (ARS) and conservative system (CRS). To increase the experimental reliability, the muscle samples were purchased 3 times from 3 Korean brands of beef produced with ARS or CRS. In the muscle tissue, cortisol level was significantly lower in ARS than CRS, (p=0.0176). But the levels of total saturated- and unsaturated-fatty acids were not significantly different between ARS and CRS (p>0.05). Of total fatty acids, the total saturated fatty acid tended to be greater in CRS and the total unsaturated fatty acid tended to be greater in ARS. However, of the total unsaturated fatty acids, the level of n-6 unsaturated fatty acids was significantly higher in ARS than CRS (p=0.0040). Especially, α-linolenic acid (ALA) and γ-linolenic acid (GLA) levels were significantly higher in ARS (p<0.01). The n-6 fatty acid content and cortisol level in muscle tissue were negatively correlated at p=0.0140. In conclusion, ARS may produce beef with higher quality which contains lower cortisol and greater n-6 fatty acids, such as ALA and GLA.

The measurement of nickel concentration in muscle tissues of Otolithes ruber in Persian Gulf waters, Iran

In order to examine and compare nickel accumulation levels in muscle tissues of Otolithes ruber in Persian Gulf waters (Bushehr province region), sampling the fish was done in both Bushehr and Asalouyeh stations during the summer 2013. After biometry, muscle tissues of the samples were separated and chemical digestion was done. Nickel accumulation levels in tissues were measured by using graphite furnace atomic absorption instrument. Based on the obtained results, mean concentrations of Nickel in muscle tissues were 0.262 ± 0.014 mgkg -1 dw in Bushehr station and 0.293 ± 0.011 mgkg -1 dw in Asalouyeh station, and it indicated no statistically significant differences between the two stations (P>0.05). The obtained concentrations and analysis done indicate that based on the WHO standard, the amount of nickel was higher than the standard levels and its use poses risks to human.

Exploration of Metallic Contamination in Fish Species of the Polluted Rivers in Bangladesh

An attempt was made to assess metal ionic toxicity levels of different fishes in the polluted rivers viz., Buriganga and Turag. Fish samples collected from two polluted rivers were analyzed for the levels of metals such as Cd, Cr, Cu, Mn, Pb, and Zn in order to elucidate the status of these contaminants in fish meant for human consumption. The detected concentrations of Cr, Cu, Mn, and Zn ions in fish species collected from the polluted rivers were below the toxic levels and did not appear to pose a threat. Among the analyzed metals, Cd and Pb ions were detected above the permissible levels in liver and muscle tissues of stinging catfish (Heteropneustesfossilis), spotted snakehead (Channapunctata) and wallago (Wallagoattu) collected from the polluted rivers causing toxicity for human consumption. Stinging catfish (Heteropneustesfossilis) was the species found to highly bioaccumulate these metals. Fish species bioconcentrated appreciable amounts of Cd and Pb as toxic metals in the liver as compared to the muscle. Levels of these toxic metals varied depending on different tissues in fish species.

Toxic effects of excessive levels of dietary selenium in juvenile yellowtail kingfish (Seriola lalandi)

Abstract Selenomethionine (SeMet) was supplemented to a fishmeal-based diet to investigate the toxic effects of excessive levels of dietary selenium (Se) in juvenile yellowtail kingfish ( Seriola lalandi ). For 10 weeks, the fish were fed one of five experimental diets; a basal diet containing 2.31 mg/kg of inherent Se or diets supplemented with SeMet to provide 4.91, 9.58, 15.43 or 20.87 mg/kg of Se. The results showed that the fish muscle proximate composition, feed conversion ratio and survival were not sensitive to dietary Se treatments; and no histopathological lesions were observed in heart and intestine tissues of the fish. The Se concentrations in liver and muscle tissues showed a strong linear positive relationship with the levels of Se in diets. Fish when fed the basal diet exhibited Se deficiency symptoms including myopathy, reduced feed intake, glutathione peroxidase activity and growth; whereas those fed the diets containing ≥ 4.91 mg Se/kg did not. While fish fed the 15.43 mg Se/kg diet did not show any toxic effects, the 20.87 mg Se/kg diet caused histopathological changes in liver and spleen as well as reduced feed intake, growth, haematocrit and hepatosomatic index, indicating Se toxicity. In conclusion, Se levels in liver and muscle tissues can be used as effective indicators of dietary Se exposure and dietary Se level between 15.43 and 20.87 mg/kg may be a threshold level in juvenile yellowtail kingfish.

Adiponectin is expressed in the pancreas of high-fat-diet-fed mice and protects pancreatic endothelial function during the development of type 2 diabetes

AimAdiponectin levels in skeletal muscle and adipose tissue have been reported to be involved in insulin resistance in rats fed with a high-fat diet (HFD). Our objective was to explore whether adiponectin is also expressed in the pancreas and what its potential role is during the development of type 2 diabetes (T2D) in outbred CD-1 mice. MethodsMale 4-week-old outbred CD-1 mice were fed an HFD to induce a polygenic model of human T2D. Adiponectin expression was examined in mouse pancreas by quantitative real-time polymerase chain reaction (qPCR), western blots and immunofluorescence analyses. Human umbilical vein endothelium cells (HUVECs) were transfected with an adiponectin-expressing lentivirus to determine the effect of adiponectin on angiogenic function in vitro. ResultsFeeding mice an HFD for 9weeks resulted in constant hyperglycaemia, obesity, impaired glucose tolerance and insulin resistance. Additional hyperinsulinaemia emerged in mice fed an HFD for 18weeks. Interestingly, aberrant expression of adiponectin was detectable in the pancreatic vascular endothelial cells (VECs) of mice fed with an HFD, but not in mice fed with regular chow (RC). Expression levels of pancreatic adiponectin varied during the development of T2D. This extraordinary expression of adiponectin in pancreatic VECs played a role in protecting endothelial function against potential damage by HFD. Our in vitro study has demonstrated that adiponectin promotes angiogenic function. ConclusionThese results reveal for the first time that adiponectin is expressed in pancreatic VECs of HFD-fed mice during the development of T2D as a protective adaptation in response to the HFD.

Featherless and feathered broilers under control versus hot conditions. 2. Breast muscle development and growth in pre- and posthatch periods

Breast meat yield (% of BW) of featherless broilers (sc/sc) is higher than that of their feathered sibs (+/sc) and contemporary broilers (+/+) under hot temperature (32°C) conditions. This study tested the hypothesis that the advantage to the featherless broiler condition with respect to breast meat yield and quality is due to differences in muscle development during pre- and posthatch periods. Broilers from the 3 genetic groups were reared under normal (26°C) and hot (32°C) conditions and slaughtered on d 29 and 47. Evaluation of myofiber diameter (mean and distribution) and blood-vessel density in breast muscle sections sampled on these days revealed that the fluctuations in breast muscle yields of the different genetic groups under different temperature conditions and the better muscle growth of the featherless broilers are due to changes in muscle hypertrophy and vascularization. In addition, the featherless broilers presented continuous satellite cell proliferation and a slower rate of differentiation compared with the feathered broilers on immediate posthatch period, suggesting a higher reserve of myogenic progeny cells that will contribute to later muscle hypertrophy. In the embryos, breast muscle yield was higher for the featherless versus feathered counterparts between embryonic day (E) 15 and E20. This was manifested in a shift toward higher myofiber diameters in the featherless embryos on E18, and a higher number of myoblasts, which could be explained by higher insulin-like growth factor-I levels in the muscle tissue and lower triiodothyronine levels in the plasma on E17. Together, the data show the advantage of being featherless under hot conditions with regard to breast muscle growth and hypertrophy, and overall performance. Moreover, featherless embryos had increased breast muscle weight compared with their feathered counterparts, likely due to a higher proliferation rate of myoblasts and higher muscle hypertrophy.