ABSTRACT
Chikungunya (CHIKV) and Mayaro (MAYV) viruses are arthritogenic alphaviruses that promote an incapacitating and long-lasting inflammatory muscle-articular disease. Despite studies pointing out the importance of skeletal muscle (SkM) in viral pathogenesis, the long-term consequences on its physiology and the mechanism of persistence of symptoms are still poorly understood. Combining molecular, morphological, nuclear magnetic resonance imaging, and histological analysis, we conduct a temporal investigation of CHIKV and MAYV replication in a wild-type mice model, focusing on the impact on SkM composition, structure, and repair in the acute and late phases of infection. We found that viral replication and induced inflammation promote a rapid loss of muscle mass and reduction in fiber cross-sectional area by upregulation of muscle-specific E3 ubiquitin ligases MuRF1 and Atrogin-1 expression, both key regulators of SkM fibers atrophy. Despite a reduction in inflammation and clearance of infectious viral particles, SkM atrophy persists until 30 days post-infection. The genomic CHIKV and MAYV RNAs were still detected in SkM in the late phase, along with the upregulation of chemokines and anti-inflammatory cytokine expression. In agreement with the involvement of inflammatory mediators on induced atrophy, the neutralization of TNF and a reduction in oxidative stress using monomethyl fumarate, an agonist of Nrf2, decreases atrogen expression and atrophic fibers while increasing weight gain in treated mice. These data indicate that arthritogenic alphavirus infection could chronically impact body SkM composition and also harm repair machinery, contributing to a better understanding of mechanisms of arthritogenic alphavirus pathogenesis and with a description of potentially new targets of therapeutic intervention.
Subject(s)
Chikungunya virus , Muscle, Skeletal , Muscular Atrophy , Oxidative Stress , Animals , Muscular Atrophy/virology , Muscular Atrophy/metabolism , Muscular Atrophy/pathology , Mice , Muscle, Skeletal/pathology , Muscle, Skeletal/metabolism , Muscle, Skeletal/virology , Chikungunya Fever/pathology , Chikungunya Fever/virology , Chikungunya Fever/metabolism , Inflammation/pathology , Inflammation/metabolism , Inflammation/virology , Muscle Proteins/metabolism , Muscle Proteins/genetics , Virus Replication , Mice, Inbred C57BL , SKP Cullin F-Box Protein Ligases/metabolism , SKP Cullin F-Box Protein Ligases/genetics , Alphavirus Infections/virology , Alphavirus Infections/pathology , Alphavirus Infections/metabolism , Tripartite Motif Proteins/metabolism , Tripartite Motif Proteins/genetics , Disease Models, Animal , Ubiquitin-Protein Ligases/metabolism , Ubiquitin-Protein Ligases/geneticsABSTRACT
BACKGROUND: The Tripartite motif (TRIM) family includes more than 80 distinct human genes. Their function has been implicated in regulating important cellular processes, including intracellular signaling, transcription, autophagy, and innate immunity. During viral infections, macrophages are key components of innate immunity that produce interferons (IFNs) and IL27. We recently published that IL27 and IFNs induce transcriptional changes in various genes, including those involved in JAK-STAT signaling. Furthermore, IL27 and IFNs share proinflammatory and antiviral pathways in monocyte-derived macrophages (MDMs), resulting in both common and unique expression of inflammatory factors and IFN-stimulated genes (ISGs) encoding antiviral proteins. Interestingly, many TRIM proteins have been recognized as ISGs in recent years. Although it is already very well described that TRIM expression is induced by IFNs, it is not fully understood whether TRIM genes are induced in macrophages by IL27. Therefore, in this study, we examined the effect of stimulation with IL27 and type I, II, and III IFNs on the mRNA expression profiles of TRIM genes in MDMs. METHODS: We used bulk RNA-seq to examine the TRIM expression profile of MDMs treated with IFNs or IL27. Initially, we characterized the expression patterns of different TRIM subfamilies using a heatmap. Subsequently, a volcano plot was employed to identify commonly differentially expressed TRIM genes. Additionally, we conducted gene ontology analysis with ClueGO to explore the biological processes of the regulated TRIMs, created a gene-gene interaction network using GeneMANIA, and examined protein-protein interactions with the STRING database. Finally, RNA-seq data was validated using RT-qPCR. Furthermore, the effect of IL27 on Mayaro virus replication was also evaluated. RESULTS: We found that IL27, similar to IFNs, upregulates several TRIM genes' expression in human macrophages. Specifically, we identified three common TRIM genes (TRIM19, 21, and 22) induced by IL27 and all types of human IFNs. Additionally, we performed the first report of transcriptional regulation of TRIM19, 21, 22, and 69 genes in response to IL27. The TRIMs involved a broad range of biological processes, including defense response to viruses, viral life cycle regulation, and negative regulation of viral processes. In addition, we observed a decrease in Mayaro virus replication in MDMs previously treated with IL27. CONCLUSIONS: Our results show that IL27, like IFNs, modulates the transcriptional expression of different TRIM-family members involved in the induction of innate immunity and an antiviral response. In addition, the functional analysis demonstrated that, like IFN, IL27 reduced Mayaro virus replication in MDMs. This implies that IL27 and IFNs share many similarities at a functional level. Moreover, identifying distinct TRIM groups and their differential expressions in response to IL27 provides new insights into the regulatory mechanisms underlying the antiviral response in human macrophages.
Subject(s)
Interferons , Macrophages , Tripartite Motif Proteins , Virus Replication , Humans , Macrophages/virology , Macrophages/immunology , Tripartite Motif Proteins/genetics , Interferons/immunology , Gene Expression Regulation , Immunity, Innate , Interleukins/genetics , Interleukins/immunology , Interleukins/metabolism , Signal TransductionABSTRACT
INTRODUCTION: Cryptorchidism is a hereditary anomaly characterized by the incomplete descent of one or both testicles to the scrotum. One of the challenges of this anomaly is that the retained testicle maintains its endocrine function. As a consequence, cryptorchid animals produce hormone-tainted meat in comparison to castrated animals and are likely to be more aggressive. Cryptorchidism can lead to reduced animal welfare outcomes and cause economic losses. Identifying genetic markers for cryptorchidism is an essential step toward mitigating these negative outcomes and may facilitate genome manipulation to reduce the occurrence of cryptorchidism. Attempts to identify such markers have used genome-wide association studies. Using whole-exome sequencing, we aimed to identify single nucleotide polymorphisms (SNPs) in the coding regions of cryptorchid pigs and to characterize functional pathways concerning these SNPs. METHODS: DNA was extracted and sequenced from 5 healthy and 5 cryptorchid animals from the Landrace breed, using the Illumina HiSeq 2500 platform. Data were pre-processed using the SeqyClean tool and further mapped against the swine reference genome (Sus scrofa 11.1) using BWA software. GATK was used to identify polymorphisms (SNPs and InDels), which were annotated using the VEP tool. Network prediction and gene ontology enrichment analysis were conducted using the Cytoscape platform, and STRING software was used for visualization. RESULTS: A total of 63 SNPs were identified across the genes PIGB, CCPG1, COMMD9, LDLRAD3, TRIM44, MYLPF, SEPTIN, ZNF48, TIA1, FAIM2, KRT18, FBP1, FBP2, CTSL, DAPK1, DHX8, GPR179, DEPDC1B, ENSSSCG00000049573, ENSSSCG00000016384, ENSSSCG00000022657, ENSSSCG00000038825, and ENSSSCG00000001229. Using pathway enrichment analyses and network prospection, we have identified the following significant adjusted p value threshold of 0.001 involved with the biological function pathways of estrogen signaling, cytoskeleton organization, and the pentose phosphate pathway. CONCLUSION: Our data suggest the involvement of new SNPs and genes in developing cryptorchidism in pigs. However, further studies are needed to validate our results in a larger cohort population. Variations in the GPR179 gene, with implications at the protein level, may be associated with the appearance of this anomaly in the swine. Finally, we are showing that the estrogen signaling pathway may be involved in the pathophysiological mechanisms of this congenital anomaly as previously reported in GWAS.
Subject(s)
Cryptorchidism , Male , Humans , Animals , Cryptorchidism/genetics , Cryptorchidism/veterinary , Genome-Wide Association Study , Exome Sequencing , Signal Transduction , Polymorphism, Single Nucleotide/genetics , Mannosyltransferases/genetics , Mannosyltransferases/metabolism , Tripartite Motif Proteins/genetics , Tripartite Motif Proteins/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , RNA Splicing Factors/genetics , RNA Splicing Factors/metabolism , DEAD-box RNA Helicases/metabolism , GTPase-Activating Proteins/geneticsABSTRACT
AIMS: This study aimed to evaluate the impact of a 12-week calorie-restricted diet and recreational sports training on gene expressions IL-15, ATROGIN-1 and MURF-1 in skeletal muscle of T2D patients. METHODS: Older adults with T2D (n = 39, 60 ± 6.0 years, BMI 33.5 ± 0.6 kg/m2) were randomly allocated to Diet+Soccer (DS), Diet+Running (DR) or Diet (D). The training sessions were moderate-to-high-intensity and performed 3 × 40 min/week for 12-weeks. Gene expression from vastus lateralis muscle obtained by qRT-PCR, dual-energy X-ray and fasting blood testing measurements were performed before and after 12-weeks. Statistical analysis adopted were two-way ANOVA and Paired t-test for gene expression, and RM-ANOVA test for the remainder variables. RESULTS: Total body weight was reduced in ~4 kg representing body fat mass in all groups after 12-weeks (P < 0.05). HbA1c values decreased in all groups post-intervention. Lipids profile improved in the training groups (P < 0.05) after 12-weeks. ATROGIN-1 and MURF-1 mRNA reduced in the DS (1.084 ± 0.14 vs. 0.754 ± 1.14 and 1.175 ± 0.34 vs. 0.693 ± 0.12, respectively; P < 0.05), while IL-15 mRNA increased in the DR (1.056 ± 0.12 vs. 1.308 ± 0.13; P < 0.05) after 12-weeks intervention. CONCLUSION: Recreational training with a moderate calorie-restricted diet can downregulates the expression of atrophy-associated myokines and increases the expression of anti-inflammatory gene IL-15.
Subject(s)
Caloric Restriction , Diabetes Mellitus, Type 2 , Exercise , Muscle, Skeletal , Aged , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/therapy , Exercise/physiology , Gene Expression , Humans , Interleukin-15/biosynthesis , Interleukin-15/genetics , Muscle Proteins/biosynthesis , Muscle Proteins/genetics , Muscle, Skeletal/metabolism , Muscle, Skeletal/physiology , RNA, Messenger/genetics , RNA, Messenger/metabolism , SKP Cullin F-Box Protein Ligases/biosynthesis , SKP Cullin F-Box Protein Ligases/genetics , Tripartite Motif Proteins/biosynthesis , Tripartite Motif Proteins/genetics , Ubiquitin-Protein Ligases/biosynthesis , Ubiquitin-Protein Ligases/geneticsABSTRACT
Hypospadias is a common congenital disorder of male genital formation. Children born small for gestational age (SGA) present a high frequency of hypospadias of undetermined etiology. No previous study investigated the molecular etiology of hypospadias in boys born SGA using massively parallel sequencing. Our objective is to report the genetic findings of a cohort of patients born SGA with medium or proximal hypospadias. We identified 46 individuals with this phenotype from a large cohort of 46,XY DSD patients, including 5 individuals with syndromic features. DNA samples from subjects were studied by either whole exome sequencing or target gene panel approach. Three of the syndromic patients have 5 main clinical features of Silver-Russell syndrome (SRS) and were first studied by MLPA. Among the syndromic patients, loss of DNA methylation at the imprinting control region H19/IGF2 was identified in 2 individuals with SRS clinical diagnosis. Two novel pathogenic variants in compound heterozygous state were identified in the CUL7 gene establishing the diagnosis of 3M syndrome in one patient, and a novel homozygous variant in TRIM37 was identified in another boy with Mulibrey nanism phenotype. Among the non-syndromic subjects, 7 rare heterozygous variants were identified in 6 DSD-related genes. However, none of the variants found can explain the phenotype by themselves. In conclusion, a genetic defect that clarifies the etiology of hypospadias was not found in most of the non-syndromic SGA children, supporting the hypothesis that multifactorial causes, new genes, and/or unidentified epigenetic defects may have an influence in this condition.
Subject(s)
Disorder of Sex Development, 46,XY , Hypospadias , DNA Methylation/genetics , Disorder of Sex Development, 46,XY/genetics , Gestational Age , Humans , Hypospadias/complications , Hypospadias/genetics , Infant, Newborn , Infant, Small for Gestational Age , Male , Tripartite Motif Proteins/genetics , Ubiquitin-Protein Ligases/geneticsABSTRACT
Skeletal muscle atrophy occurs in several pathological conditions, such as cancer, especially during cancer-induced cachexia. This condition is associated with increased morbidity and poor treatment response, decreased quality of life, and increased mortality in cancer patients. A leucine-rich diet could be used as a coadjutant therapy to prevent muscle atrophy in patients suffering from cancer cachexia. Besides muscle atrophy, muscle function loss is even more important to patient quality of life. Therefore, this study aimed to investigate the potential beneficial effects of leucine supplementation on whole-body functional/movement properties, as well as some markers of muscle breakdown and inflammatory status. Adult Wistar rats were randomly distributed into four experimental groups. Two groups were fed with a control diet (18% protein): Control (C) and Walker 256 tumour-bearing (W), and two other groups were fed with a leucine-rich diet (18% protein + 3% leucine): Leucine Control (L) and Leucine Walker 256 tumour-bearing (LW). A functional analysis (walking, behaviour, and strength tests) was performed before and after tumour inoculation. Cachexia parameters such as body weight loss, muscle and fat mass, pro-inflammatory cytokine profile, and molecular and morphological aspects of skeletal muscle were also determined. As expected, Walker 256 tumour growth led to muscle function decline, cachexia manifestation symptoms, muscle fibre cross-section area reduction, and classical muscle protein degradation pathway activation, with upregulation of FoxO1, MuRF-1, and 20S proteins. On the other hand, despite having no effect on the walking test, inflammation status or muscle oxidative capacity, the leucine-rich diet improved muscle strength and behaviour performance, maintained body weight, fat and muscle mass and decreased some protein degradation markers in Walker 256 tumour-bearing rats. Indeed, a leucine-rich diet alone could not completely revert cachexia but could potentially diminish muscle protein degradation, leading to better muscle functional performance in cancer cachexia.
Subject(s)
Cachexia/diet therapy , Forkhead Box Protein O1/genetics , Leucine/pharmacology , Muscle Proteins/genetics , Muscular Atrophy/diet therapy , Tripartite Motif Proteins/genetics , Ubiquitin-Protein Ligases/genetics , Animals , Cachexia/genetics , Cachexia/pathology , Dietary Supplements , Humans , Inflammation/diet therapy , Inflammation/genetics , Inflammation/pathology , Leucine/metabolism , Muscular Atrophy/genetics , Muscular Atrophy/pathology , Neoplasms/complications , Neoplasms/diet therapy , Neoplasms/genetics , Proteolysis/drug effects , Quality of Life , RatsABSTRACT
Physical exercise has profound effects on quality of life and susceptibility to chronic disease; however, the regulation of skeletal muscle function at the molecular level after exercise remains unclear. We tested the hypothesis that the benefits of exercise on muscle function are linked partly to microtraumatic events that result in accumulation of circulating heme. Effective metabolism of heme is controlled by Heme Oxygenase-1 (HO-1, Hmox1), and we find that mouse skeletal muscle-specific HO-1 deletion (Tam-Cre-HSA-Hmox1fl/fl) shifts the proportion of muscle fibers from type IIA to type IIB concomitant with a disruption in mitochondrial content and function. In addition to a significant impairment in running performance and response to exercise training, Tam-Cre-HSA-Hmox1fl/fl mice show remarkable muscle atrophy compared to Hmox1fl/fl controls. Collectively, these data define a role for heme and HO-1 as central regulators in the physiologic response of skeletal muscle to exercise.
Subject(s)
Heme Oxygenase-1/genetics , Heme/metabolism , Membrane Proteins/genetics , Muscle Fibers, Skeletal/metabolism , Muscular Atrophy/genetics , Physical Conditioning, Animal/physiology , 5-Aminolevulinate Synthetase/genetics , 5-Aminolevulinate Synthetase/metabolism , Animals , Ferrochelatase/genetics , Ferrochelatase/metabolism , Gene Expression Regulation , Heme Oxygenase-1/deficiency , Isoenzymes/genetics , Isoenzymes/metabolism , Low Density Lipoprotein Receptor-Related Protein-1/genetics , Low Density Lipoprotein Receptor-Related Protein-1/metabolism , Male , Membrane Proteins/deficiency , Membrane Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Mitochondria/genetics , Mitochondria/metabolism , Muscle Proteins/genetics , Muscle Proteins/metabolism , Muscular Atrophy/metabolism , Muscular Atrophy/physiopathology , MyoD Protein/genetics , MyoD Protein/metabolism , PAX7 Transcription Factor/genetics , PAX7 Transcription Factor/metabolism , Signal Transduction , Tripartite Motif Proteins/genetics , Tripartite Motif Proteins/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolismABSTRACT
BACKGROUND: Burn injuries (BIs) due to scalding are one of the most common accidents among children. BIs greater than 40% of total body surface area are considered extensive and result in local and systemic response. We sought to assess morphological and myogenic mechanisms through both short- and long-term intensive insulin therapies that affect the skeletal muscle after extensive skin BI in young rats. MATERIALS AND METHODS: Wistar rats aged 21 d were distributed into four groups: control (C), control with insulin (C + I), scald burn injury (SI), and SI with insulin (SI + I). The SI groups were submitted to a 45% total body surface area burn, and the C + I and SI + I groups received insulin (5 UI/Kg/d) for 4 or 14 d. Glucose tolerance and the homeostatic model assessment of insulin resistance index were determined. Gastrocnemius muscles were analyzed for histopathological, morphometric, and immunohistochemical myogenic parameters (Pax7, MyoD, and MyoG); in addition, the expression of genes related to muscle atrophy (MuRF1 and MAFbx) and its regulation (IGF-1) were also assessed. RESULTS: Short-term treatment with insulin favored muscle regeneration by primary myogenesis and decreased muscle atrophy in animals with BIs, whereas the long-term treatment modulated myogenesis by increasing the MyoD protein. Both treatments improved histopathological parameters and secondary myogenesis by increasing the MyoG protein. CONCLUSIONS: Treatment with insulin benefits myogenic parameters during regeneration and modulates MuRF1, an important mediator of muscle atrophy.
Subject(s)
Burns/complications , Insulin/administration & dosage , Muscle Development/drug effects , Muscular Atrophy/prevention & control , Animals , Blood Glucose/analysis , Body Surface Area , Burns/pathology , Burns/physiopathology , Gene Expression/drug effects , Insulin-Like Growth Factor I/genetics , Male , Muscle Proteins/genetics , Muscle, Skeletal/chemistry , Muscle, Skeletal/pathology , Muscle, Skeletal/physiopathology , Muscular Atrophy/etiology , Muscular Atrophy/genetics , MyoD Protein/analysis , Myogenin/analysis , Paired Box Transcription Factors/analysis , Rats , Rats, Wistar , SKP Cullin F-Box Protein Ligases/genetics , Tripartite Motif Proteins/genetics , Ubiquitin-Protein Ligases/geneticsABSTRACT
INTRODUCTION: Various pathologies and lifestyle factors, such as nutritional factors and physical exercises, can alter the gene expression of proteins related to synthesis and degradation. AIM: We performed a systematic review of atrophy models, cancer models, burn models, sepsis models, cardiac insufficiency models, amino acid supplementation models, protein supplementation models, and miscellaneous models that have altered the gene expression of MTOR, MURF-1, or MAFBX in rats and mice. MATERIALS AND METHODS: We searched the literature in the following databases: Medline, Scielo.org, Scielo.br, Redib, Lilacs, and the Periodicos Capes. RESULTS: We selected 56 articles for this review. DISCUSSION: Several conditions can alter the gene expression of muscle proteins under conditions that stimulate muscle degradation pathways. Therefore, treatments must normalize the expression of the degradation pathways and potentiate the synthesis pathways so the muscular tissue confers an increase in functional capacity and thus, survival in diseased patients. Therefore, the reversal of the mechanisms that promote its depletion must be achieved. CONCLUSION: Identification of the atrophic mechanisms present in pathologies and other conditions of muscular disuse in the scientific literature is fundamental for the adoption of clinical strategies to prevent protein degradation and to promote the maintenance and/or increase of muscle tissue. Such strategies include physical exercise, protein supplementation, and/or pharmacological applications, aimed toward restoring the fullness of functional capacity.
Subject(s)
Gene Expression Regulation/genetics , Muscle Proteins/genetics , SKP Cullin F-Box Protein Ligases/genetics , TOR Serine-Threonine Kinases/genetics , Tripartite Motif Proteins/genetics , Ubiquitin-Protein Ligases/genetics , Amino Acid Metabolism, Inborn Errors/genetics , Amino Acid Metabolism, Inborn Errors/pathology , Animals , Arrhythmias, Cardiac/genetics , Arrhythmias, Cardiac/pathology , Atrophy/genetics , Atrophy/pathology , Burns/genetics , Burns/pathology , Disease Models, Animal , Humans , Mice , Neoplasms/genetics , Neoplasms/pathology , Rats , Sepsis/genetics , Sepsis/pathologyABSTRACT
The myofibrillar fragmentation index (MFI) is an indicative trait for meat tenderness. Longissimus thoracis muscle samples from the 20 most extreme bulls (out of 80 bulls set) for MFI (high (n = 10) and low (n = 10) groups) trait were used to perform transcriptomic analysis, using RNA Sequencing (RNA-Seq). An average of 24.616 genes was expressed in the Nellore muscle transcriptome analysis. A total of 96 genes were differentially expressed (p value ≤ 0.001) between the two groups of divergent bulls for MFI. The HEBP2 and BDH1 genes were overexpressed in animals with high MFI. The MYBPH and MYL6, myosin encoders, were identified. The differentially expressed genes were related to increase mitochondria efficiency, especially in cells under oxidative stress conditions, and these also were related to zinc and calcium binding, membrane transport, and muscle constituent proteins, such as actin and myosin. Most of those genes were involved in metabolic pathways of oxidation-reduction, transport of lactate in the plasma membrane, and muscle contraction. This is the first study applying MFI phenotypes in transcriptomic studies to identify and understand differentially expressed genes for beef tenderness. These results suggest that differences detected in gene expression between high and low MFI animals are related to reactive mechanisms and structural components of oxidative fibers under the condition of cellular stress. Some genes may be selected as positional candidate genes to beef tenderness, MYL6, MYBPH, TRIM63, TRIM55, TRIOBP, and CHRNG genes. The use of MFI phenotypes could enhance results of meat tenderness studies.
Subject(s)
Cattle/genetics , Muscle, Skeletal/metabolism , Quantitative Trait, Heritable , Red Meat/standards , Transcriptome , Animals , Cattle/metabolism , Cytoskeletal Proteins/genetics , Cytoskeletal Proteins/metabolism , Gene Expression Profiling , Heme-Binding Proteins/genetics , Heme-Binding Proteins/metabolism , Male , Myosins/genetics , Myosins/metabolism , Receptors, Nicotinic/genetics , Receptors, Nicotinic/metabolism , Tripartite Motif Proteins/genetics , Tripartite Motif Proteins/metabolismABSTRACT
Myostatin is a myokine that regulates muscle function and mass, producing muscle atrophy. Myostatin induces the degradation of myofibrillar proteins, such as myosin heavy chain or troponin. The main pathway that mediates protein degradation during muscle atrophy is the ubiquitin proteasome system, by increasing the expression of atrogin-1 and MuRF-1. In addition, myostatin activates the NF-κB signaling pathway. Renin-angiotensin system (RAS) also regulates muscle mass. Angiotensin (1-7) (Ang-(1-7)) has anti-atrophic properties in skeletal muscle. In this paper, we evaluated the effect of Ang-(1-7) on muscle atrophy and signaling induced by myostatin. The results show that Ang-(1-7) prevented the decrease of the myotube diameter and myofibrillar protein levels induced by myostatin. Ang-(1-7) also abolished the increase of myostatin-induced reactive oxygen species production, atrogin-1, MuRF-1, and TNF-α gene expressions and NF-κB signaling activation. Ang-(1-7) inhibited the activity mediated by myostatin through Mas receptor, as is demonstrated by the loss of all Ang-(1-7)-induced effects when the Mas receptor antagonist A779 was used. Our results show that the effects of Ang-(1-7) on the myostatin-dependent muscle atrophy and signaling are blocked by MK-2206, an inhibitor of Akt/PKB. Together, these data indicate that Ang-(1-7) inhibited muscle atrophy and signaling induced by myostatin through a mechanism dependent on Mas receptor and Akt/PKB.
Subject(s)
Angiotensin I/pharmacology , Muscle Fibers, Skeletal/drug effects , Myostatin/pharmacology , NF-kappa B/metabolism , Peptide Fragments/pharmacology , Signal Transduction , Animals , Cell Line , Mice , Muscle Fibers, Skeletal/metabolism , Muscle Proteins/genetics , Muscle Proteins/metabolism , Reactive Oxygen Species/metabolism , SKP Cullin F-Box Protein Ligases/genetics , SKP Cullin F-Box Protein Ligases/metabolism , Tripartite Motif Proteins/genetics , Tripartite Motif Proteins/metabolism , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolismABSTRACT
The aim of this study was to examine the activation of skeletal muscle signaling pathways related to protein synthesis and the gene expression of regeneration/degradation markers following repeated bouts of eccentric cycling. Nine untrained men (25.4 ± 1.9 yr) performed two 30-min eccentric cycling bouts (ECC1, ECC2) at 85% of maximal concentric workload, separated by 2 wk. Muscle biopsies were taken from the vastus lateralis before and 2 h after each bout. Indirect markers of muscle damage were assessed before and 24-48 h after exercise. Changes in the Akt/mammalian target of rapamycin (mTOR)/rbosomal protein S6 kinase 1 (S6K1)/ribosomal protein S6 (rpS6) and MAPK signaling pathways were measured by Western blot and changes in mRNA expression of IL-6 and IL-1ß, and myogenic regulatory factors (MRFs) were measured by real-time PCR. ECC1 induced greater increases in indirect markers of muscle damage compared with ECC2. Phosphorylation of S6K1 and rpS6 increased after both exercise bouts (P < 0.05), whereas phosphorylation of mTOR increased after ECC2 only (P = 0.03). Atrogin-1 mRNA expression decreased after ECC1 and ECC2 (P < 0.05) without changes in muscle RING-finger protein-1 mRNA. Basal mRNA levels of myoblast determination protein-1 (MyoD), MRF4, and myogenin were higher 2 wk after ECC1 (P < 0.05). MRF4 mRNA increased after ECC1 and ECC2 (P < 0.05), whereas MyoD mRNA expression increased only after ECC1 (P = 0.03). Phosphorylation of JNK and p38 MAPK increased after both exercise bouts (P < 0.05), similar to IL-6 and IL-1ß mRNA expression. All together, these results suggest that differential regulation of the mTOR pathway and MRF expression could mediate the repeated bout effect observed between an initial and secondary bout of eccentric exercise.
Subject(s)
Bicycling , Exercise/physiology , Gene Expression , MAP Kinase Signaling System/genetics , Protein Biosynthesis/genetics , Quadriceps Muscle/metabolism , Regeneration/genetics , Adult , Humans , Interleukin-1beta/genetics , Interleukin-6/genetics , MAP Kinase Kinase 4/metabolism , Male , Muscle Proteins/genetics , Muscle, Skeletal/metabolism , Muscle, Skeletal/physiology , MyoD Protein/genetics , Myogenic Regulatory Factors/genetics , Myogenin/genetics , Proto-Oncogene Proteins c-akt/metabolism , Ribosomal Protein S6/metabolism , Ribosomal Protein S6 Kinases, 90-kDa/metabolism , SKP Cullin F-Box Protein Ligases/genetics , TOR Serine-Threonine Kinases/metabolism , Tripartite Motif Proteins/genetics , Ubiquitin-Protein Ligases/genetics , Young Adult , p38 Mitogen-Activated Protein Kinases/metabolismABSTRACT
Knee osteoarthritis (KOA) is associated with muscle weakness, but it is unclear which structures are involved in the muscle changes. This study assessed morphological alterations and the expression of genes and proteins linked to muscular atrophy and neuromuscular junctions (NMJs) in KOA, induced by anterior cruciate ligament transection (ACLT) in rats. Two groups of rats were assessed: control (without intervention) and KOA (ACLT surgery in the right knee). After 8 weeks, quadriceps, tibialis anterior (TA) and gastrocnemius muscles were analyzed (area of muscle fibers, NMJ, gene and protein expression). KOA group showed atrophy in quadriceps (15.7%) and TA (33%), with an increase in atrogin-1 and muscle RING-finger protein-1 (MuRF-1). KOA group showed quadriceps NMJ remodeling (reduction area and perimeter) and decrease in NMJ diameter in TA muscle. The expression of nicotinic acetylcholine receptor (nAChR) γ-nAChR increased and that of α-nAChR and muscle specific tyrosine kinase (MuSK) declined in the quadriceps, with a decrease in ε-nAChR in TA. MuRF-1 protein expression increased in quadriceps and TA, with no changes in neural cell adhesion molecule (NCAM). In conclusion, ACLT-induced KOA promotes NMJ remodeling and atrophy in quadriceps and TA muscles, associated with inflammatory signs and changes in muscle gene and protein expression.
Subject(s)
Muscle Proteins/genetics , Muscle, Skeletal/metabolism , Muscular Atrophy/genetics , Neuromuscular Junction/metabolism , Osteoarthritis, Knee/genetics , Quadriceps Muscle/metabolism , Animals , Anterior Cruciate Ligament/physiopathology , Anterior Cruciate Ligament/surgery , Gene Expression , Muscle Proteins/metabolism , Muscle Weakness/genetics , Muscle Weakness/metabolism , Muscle Weakness/physiopathology , Muscle, Skeletal/physiopathology , Muscular Atrophy/metabolism , Muscular Atrophy/physiopathology , Neuromuscular Junction/physiopathology , Osteoarthritis, Knee/metabolism , Osteoarthritis, Knee/physiopathology , Quadriceps Muscle/physiopathology , Rats, Wistar , Receptor Protein-Tyrosine Kinases/genetics , Receptor Protein-Tyrosine Kinases/metabolism , Receptors, Nicotinic/genetics , Receptors, Nicotinic/metabolism , SKP Cullin F-Box Protein Ligases/genetics , SKP Cullin F-Box Protein Ligases/metabolism , Tripartite Motif Proteins/genetics , Tripartite Motif Proteins/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolismABSTRACT
Growth is one of the main biological processes in aquatic organisms that is affected by environmental fluctuations such as upwelling (characterized by food-rich waters). In fish, growth is directly related with skeletal muscle increase; which represents the largest tissue of body mass. However, the effects of upwelling on growth, at the physiological and molecular level, are unknown. This study used Girella laevifrons (one of the most abundant intertidal fish in Eastern South Pacific) as a biological model, considering animals from upwelling (U) and non-upwelling (NU) areas. Here, we evaluated the effect of nutritional composition and food availability on growth performance and expression of key growth-related genes (insulin-kike growth factor 1 (igf1) and myosin heavy-chain (myhc)) and atrophy-related genes (muscle ring-finger 1 (murf1), F-box only protein 32 (atrogin-1) and BCL2/adenovirus E1B 19kDa-interacting protein 3 (bnip3)). We reported that, among zones, U fish displayed higher growth performance in response to nutritional composition, specifically between protein- and fiber-rich diets (~1g). We also found in NU fish that atrophy-related genes were upregulated with fiber-rich diet and during fasting (~2-fold at minimum respect U). In conclusion, our results suggest that the growth potential of upwelling fish may be a consequence of differential muscle gene expression. Our data provide a preliminary approach contributing on how upwelling influence fish growth at the physiological and molecular levels. Future studies are required to gain further knowledge about molecular differences between U and NU animals, as well as the possible applications of this knowledge in the aquaculture industry.
Subject(s)
Gene Expression Regulation, Developmental , Muscle Proteins/genetics , Muscle, Skeletal/metabolism , Perciformes/growth & development , Perciformes/genetics , Animals , Diet, Carbohydrate Loading , Ecosystem , Food Chain , Insulin-Like Growth Factor I/genetics , Insulin-Like Growth Factor I/metabolism , Muscle Proteins/metabolism , Muscle, Skeletal/growth & development , Perciformes/metabolism , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Rivers/chemistry , SKP Cullin F-Box Protein Ligases/genetics , SKP Cullin F-Box Protein Ligases/metabolism , Seawater/chemistry , Tripartite Motif Proteins/genetics , Tripartite Motif Proteins/metabolismABSTRACT
We performed a retrospective genome-wide association study in HIV-infected individuals who were treated with dendritic cell-based immunotherapy in clinical trials performed by two research groups (Spain and Brazil). We aimed to identify host genetic variants influencing treatment response. The Illumina Human Core Exome 12 v 1.0 Bead Chip with over 250,000 markers was used to analyze genetic factors affecting treatment response. Additionally, we performed a meta-analysis of the results obtained from Spanish and Brazilian patients. We identified a genetic variation (rs7935564 G allele) in TRIM22 gene, which encodes TRIM22 protein acting like a HIV restriction factor, as being associated with good response to dendritic cell-based immunotherapy. We then verified the impact of TRIM22 rs7935564 SNP in susceptibility to HIV infection and disease progression by assessing the influence of biogeographic ancestry in the distribution of allelic and genotype frequencies in three populations from Italy, Brazil and Zambia. TRIM22 rs7935564 genotyping indicated association of G rs7935564 allele with long-term non-progression of HIV disease in Italian patients, thus corroborating our hypothesis that it is involved as a restriction factor in dendritic cell-based immunotherapy response. TRIM22 rs7935564 polymorphism was associated with good response to dendritic cell-based immunotherapy. We hypothesize that in selecting patients for treatment, there is a possible bias related to the natural presence of restriction factors that are genetically determined and could influence final outcome of therapy.