• Journal of Nutrition and Health
• /
• v.54 no.6
• /
• pp.594-602
• /
• 2021

Purpose: The zinc transporter ZIP7 is known to regulate glucose metabolism in skeletal muscles, and skeletal muscles are known to play a critical role in glycemic control. The present study examines the effects of dietary zinc supplementation on the blood glucose concentration and expression of ZIP7 in skeletal muscle obtained from obese mice fed a high-fat diet (HF). Methods: C57BL/6J male mice were divided into three groups and were administered either a HF (60% of total calories from fat), HF supplemented with zinc (HF+Zn, 60% calories from fat + 300 mg zinc/kg diet), or low-fat diet (CON, 10% calories from fat), for 15 weeks. Results: Compared to CON group mice, the final body weights and adipose tissue weights were significantly increased, while the skeletal muscle weights were significantly decreased in mice belonging to the HF and HF+Zn groups. The HF+Zn group had significantly lower levels of fasting blood glucose concentrations than the HF group. Similarly, zinc supplementation significantly decreased the HF-elevated area under the curve values obtained from the oral glucose tolerance test. Skeletal muscle protein levels of ZIP7 in samples obtained from the HF group were significantly decreased as compared to the CON group. Conversely, the skeletal ZIP7 protein levels in the HF+Zn group were significantly increased as compared to the HF group. Moreover, the protein levels of phosphorylated-AKT and glucose transporter 4 in the skeletal muscle were significantly increased subsequent to zinc supplementation. Conclusion: Our data demonstrates that zinc supplementation up-regulates the skeletal muscle ZIP7 expression, which is associated with improved glucose tolerance in the obesity.

• Journal of Animal Reproduction and Biotechnology
• /
• v.36 no.4
• /
• pp.314-322
• /
• 2021

Paired box protein, PAX7, is a key molecule for the specification, maintenance and skeletal muscle regeneration of muscle satellite cells. In this study, we identified and characterized the cDNA and amino acid sequences of PAX7 from black sea bream (Acanthopagrus schlegelii) via molecular cloning and sequence analysis. A. schlegelii PAX7 cDNA was comprised of 1,524 bp encoding 507 amino acids and multiple sequence alignment analysis of the translated amino acids showed that it contained three domains including paired DNA-binding domain, homeobox domain and OAR domain which were well conserved across various animal species investigated. Pairwise Sequence Alignment indicated that A. schlegelii PAX7 had the same amino acid sequences with that of yellowfin seabream (A. latus) and 99.8% identity and similarity with that of gilt-head bream (Sparus aurata). Molecular phylogenetic analysis confirmed that A. schlegelii PAX7 formed a monophyletic group with those of teleost and most closely related with those of the fish that belong to Sparidae family including A. latus and S. aurata. In the investigation of its tissue specific mRNA expression, the expression was specifically identified in skeletal muscle tissue and a weak expression was also shown in gonad tissue. The cultured cells derived from skeletal muscle tissues expressed PAX7 mRNA at early passage but the expression was not observed after several times of subculture.

• Asian-Australasian Journal of Animal Sciences
• /
• v.10 no.5
• /
• pp.528-533
• /
• 1997

Twenty four female Sprague-Dawley rats weighing about 190 g were used to examine changes in muscle cAMP concentrations and steady-state levels of skeletal muscle ${\alpha}$-actin mRNA during chronic administration of cimaterol, a ${\beta}$-adrenergic agonist. Cimaterol was mixed in a powdered rat diet at 10 mg/kg diet. At 3 and 21 days after the start of treatment, skeletal muscle and heart samples were collected for the measurement of cAMP concentrations and skeletal muscle ${\alpha}$-actin mRNA levels. Cimaterol increased (p < 0.01) body weight gain gradually during the first seven days of the trial period, but not thereafter. Most skeletal muscle weights and the ratio of muscle weight to body weight were increased (p < 0.05) by cimaterol treatment both at 3 and 21 days. Heart weight was also increased (p < 0.05) by cimaterol treatment at 3 and 21 days, but the ratio of heart weight to body weight was increased (p < 0.05) only at 3 day. Cimaterol decreased (p < 0.05) cAMP concentration of gastrocnemius muscle at both 3 and 21 days after treatment. However, cimaterol tended (p = 0.07) to increase cAMP concentration at 3 days in the heart. Cimaterol tended (p = 0.08) to increase the steady-state level of ${\alpha}$-actin mRNA by 60% in gastrocnemius muscle at 3 days but had no effect at 21 days. The results indicate that the pattern of hypertrophic response to chronic dietary administration of cimaterol is different between cardiac and skeletal muscle. In skeletal muscles it appears that the hypertrophy induced by cimaterol is partly due to stimulated myofibrillar protein synthesis at a pre-translational level.

• Journal of Life Science
• /
• v.26 no.7
• /
• pp.758-763
• /
• 2016

Fatty acid transporters are key mediators of skeletal muscle lipid metabolism. Several protein groups have been implicated in cellular long-chain fatty acid uptake or oxidation, including fatty acid transporter proteins (FATPs), the plasma membrane fatty acid-binding protein (FABPpm), and the fatty acid translocase (FAT/CD36). FAT/CD36 is highly expressed in skeletal muscle and known to be regulated by various factors such as exercise and hormones. Insulin-like growth factor-I (IGF-I) is a well-known regulator of skeletal muscle cells. However, it has not been studied whether there is any interaction between IGF-I and FAT/CD36 in skeletal muscle cells. In this study, the effects of IGF-I treatment on FAT/CD36 induction were examined. Differentiated C2C12 cells were treated with 20 ng/ml of IGF-I at different time points. Treatment of C2C12 cells with IGF-I resulted in increased FAT/CD36 mRNA and protein expression. After 24 and 48 hr of IGF-I treatment, FAT/CD36 mRNA increased 89% and 24% respectively. The increase of both proteins returned to the control level after 72 hr of IGF-I treatment, suggesting that the FAT/CD36 gene is regulated pretranslationally by IGF-I in skeletal muscle cells. These results suggest that IGF-I can regulate the expression of FAT/CD36 in skeletal muscle cells. In conclusion, IGF-I induces a rapid transcriptional modification of the FAT/CD36 gene in C2C12 skeletal muscle cells and has modulating effects on fatty acid uptake proteins as well as oxidative proteins.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.32 no.3
• /
• pp.221-230
• /
• 2022

Objectives: The aim of this study is to evaluate the association between shiftwork and skeletal muscle mass index in a single university health check-up. Methods: We used data from 98,227 workers who answered in a special interview on health check-up at a local university hospital from 2014 to 2020. Pearson correlation analysis was conducted for comparing the association between skeletal muscle mass index and demographic and hematological variables in shiftwork and non-shiftwork groups. Mixed linear model analysis after controlling demographic and hematological variables was used to analyze the difference of skeletal muscle mass index between groups at every visit for seven years. Results: In linear regression analysis, the variables most significantly correlated with skeletal muscle index in both groups were shiftwork(p=0.049), BMI(p<0.001), hypertension(p=0.024), platelet(p<0.001), total protein (p<0.001), AST(p=0.028), ALT(p=0.003), ALP(p<0.001), total cholesterol(p=0.002), triglyceride(p=0.019), BUN (p=0.001), creatinine(p<0.001), and uric acid(p=0.002). After the adjustment for demographic and hematologic variables, the skeletal muscle mass index at every visit was decreased both in the shiftwork group and non-shiftwork group. The slope of the shiftwork group was -0.240 and non-shiftwork group -0.149, showing a significant difference (p<0.001). Conclusions: In the shiftwork group, the skeletal muscle mass index showed a tendency to decrease markedly over time compared to the non-shiftwork group. It is presumed that shift workers' skeletal muscle health was adversely affected by changes in the biological clock due to changes in wake-up and sleep patterns, and changes in food intake.

• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.10
• /
• pp.1496-1502
• /
• 2006

Skeletal muscle contains slow and fast twitch fibers. These skeletal muscle fibers express type I and type II myosin, respectively, and these myosin isoenzymes have different ATPase activity. The aim of this study was to investigate protein profiles of bovine skeletal muscles by proteomic analysis. Fifty seven spots of distinct proteins were excised and characterized. The expression of sixteen spots was differed in longissimus dorsi muscle with a minimal 2-fold change compared to biceps femoris muscle. The majority of differentially expressed proteins belonged to metabolic regulation-related proteins such as glyceraldehyde 3-phosphate dehydrogenase, triosephosphate isomerase and carbonic anhydrase 3. The real time-PCR assay confirmed an increase or induction of specific genes: RGS12TS isoform, GAPDH, triosephosphate isomerase and carbonic anhydrase. These results suggest that the expression of metabolic proteins is under a specific control system in different bovine skeletal muscle. These observations could have significant implications for understanding the physiological regulation of bovine skeletal muscles.

• Asian-Australasian Journal of Animal Sciences
• /
• v.32 no.2
• /
• pp.170-175
• /
• 2019

Objective: Uncoupling protein 3 gene (UCP3) is a candidate gene associated with the meat quality of pigs. The aim of this study was to explore the regulation mechanism of UCP3 expression and provide a theoretical basis for the research of the function of porcine UCP3 gene in meat quality. Methods: Bisulfite sequencing polymerase chain reaction (PCR) and quantitative real-time PCR (Q-PCR) were used to analyze the methylation of UCP3 5′-flanking region and UCP3 mRNA expression in the adipose tissue or skeletal muscle of three pig breeds at different ages (1, 90, 210-day-old Putian Black pig; 90-day-old Duroc; and 90-day-old Dupu). Results: Results showed that two cytosine-guanine dinucleotide (CpG) islands are present in the promoter region of porcine UCP3 gene. The second CpG island located in the core promoter region contained 9 CpG sites. The methylation level of CpG island 2 was lower in the adipose tissue and skeletal muscle of 90-day-old Putian Black pigs compared with 1-day-old and 210-day-old Putian Black pigs, and the difference also existed in the skeletal muscle among the three 90-day-old pig breeds. Furthermore, the obvious changing difference of UCP3 mRNA expression was observed in the skeletal muscle of different groups. However, the difference of methylation status and expression level of UCP3 gene was not significant in the adipose tissue. Conclusion: Our data indicate that UCP3 mRNA expression level was associated with the methylation status of UCP3 promoter in the skeletal muscle of pigs.

• Korean Journal of Exercise Nutrition
• /
• v.13 no.2
• /
• pp.131-140
• /
• 2009

The aim of this study was to investigate the expression of PPAR-α, -β/δ, -γ, PGC-1α, GLUT-4 and p-AMPK-α₂ protein in the skeletal muscle of diabetic induced-rats by endurance training combined with rosiglitazone. The expression of PPAR-α, -β/δ, -γ, PGC-1α, GLUT-4 and p-AMPK-α₂ protein in red and white gastrocnemius by western blotting. The body weight was higher in diabetic induced-rats compared to the normal rats and after the treatment of exercise combined with rosiglitazone was significantly reduced in the all group. The levels of blood glucose was higher in diabetic induced-rats compared to the normal rats and after the treatment of exercise combined with rosiglitazone was significantly reduced in the all group. The expression of PPAR-α, -γ, PGC-1α in skeletal muscle of diabetic induced-rats were increased all groups and increased significantly in the group with exercise combined with rosiglitazone. The expression of GLUT-4 and p-AMPK-α₂ protein in the skeletal muscle of diabetic induced-rats were increased all groups and increased significantly in the group with exercise combined with rosiglitazoneI. These results suggest that exercise training and rosiglitazone may act as complementary therapies for the treatment of insulin rasistance.

• Animal Bioscience
• /
• v.34 no.6
• /
• pp.1078-1087
• /
• 2021

Objective: Skeletal muscle satellite cells (SMSCs) are significant for the growth, regeneration, and maintenance of skeletal muscle after birth. However, currently, few studies have been performed on the isolation, culture and inducing differentiation of goose muscle satellite cells. Previous studies have shown that C1q and tumor necrosis factor-related protein 3 (CTRP3) participated in the process of muscle growth and development, but its role in the goose skeletal muscle development is not yet clear. This study aimed to isolate, culture, and identify the goose SMSCs in vitro. Additionally, to explore the function of CTRP3 in goose SMSCs. Methods: Goose SMSCs were isolated using 0.25% trypsin from leg muscle (LM) of 15 to 20 day fertilized goose eggs. Cell differentiation was induced by transferring the cells to differentiation medium with 2% horse serum and 1% penicillin streptomycin. Immunofluorescence staining of Desmin and Pax7 was used to identify goose SMSCs. Quantitative realtime polymerase chain reaction and western blot were applied to explore developmental expression profile of CTRP3 in LM and the regulation of CTRP3 on myosin heavy chains (MyHC), myogenin (MyoG) expression and Notch signaling pathway related genes expression. Results: The goose SMSCs were successfully isolated and cultured. The expression of Pax7 and Desmin were observed in the isolated cells. The expression of CTRP3 decreased significantly during leg muscle development. Overexpression of CTRP3 could enhance the expression of two myogenic differentiation marker genes, MyHC and MyoG. But knockdown of CTRP3 suppressed their expression. Furthermore, CTRP3 could repress the mRNA level of Notch signaling pathway-related genes, notch receptor 1, notch receptor 2 and hairy/enhancer-of-split related with YRPW motif 1, which previously showed a negative regulation in myoblast differentiation. Conclusion: These findings provide a useful cell model for the future research on goose muscle development and suggest that CTRP3 may play an essential role in skeletal muscle growth of goose.

• Proceedings of the Korean Biophysical Society Conference
• /
• 2001.06a
• /
• pp.46-46
• /
• 2001

Evidence has suggested that an anion channel blocker, 4, 4'-diisothiocyanatostilbene-2, 2' disulfonic acid (DIDS) could trigger Ca release from skeletal sarcoplasmic reticulum (SR) by binding to a 30 kDa SR protein. Since the high molecular weight $Ca^{2＋}$ release channel (CRC)/ryanodine receptor (RyR) is the main SR protein that conducts $Ca^{2＋}$ efflux in skeletal muscles, the relationship between CRC and the 30kDa protein remains to be elucidated.(omitted)