Higher serum myostatin levels are associated with lower insulin sensitivity in adults with overweight/obesity.

Myostatin inhibition improves insulin sensitivity in preclinical and clinical models; however, studies investigating the relationship between serum myostatin levels and insulin sensitivity are discrepant. Sensitive and specific myostatin LC-MS/MS assays are now available to accurately assess serum myostatin level in vivo. We sought to determine whether higher serum myostatin levels are independently associated with lower insulin sensitivity in adults with overweight/obesity. Participants included 74 adults, 20-65 years old, BMI ≥25 kg/m2 without type 2 diabetes. Appendicular lean mass (ALM) was measured by dual-energy x-ray absorptiometry; visceral adipose tissue (VAT) was measured by computed tomography. Main outcome measures were serum myostatin levels (LC-MS/MS) and insulin sensitivity (Matsuda index). Mean age was 48 ± 12 years, and BMI was 33.1 ± 5.6 kg/m2 (mean ± SD). Men had higher mean serum myostatin levels versus women (8.3 ± 1.9 vs. 7.2 ± 1.9 ng/mL, p = 0.01) and higher serum myostatin levels were associated with higher ALM (R = 0.34, p = 0.003). Higher serum myostatin levels were associated with lower Matsuda index (R = -0.44, p = 0.0004), which remained significant after controlling for BMI, VAT, ALM, and sex. In conclusion, higher serum myostatin levels are independently associated with lower insulin sensitivity in adults with overweight/obesity and may be a marker of or play a mechanistic role in the development of insulin resistance.

Electroporation Delivery of Cas9 sgRNA Ribonucleoprotein-Mediated Genome Editing in Sheep IVF Zygotes.

The utilization of electroporation for delivering CRISPR/Cas9 system components has enabled efficient gene editing in mammalian zygotes, facilitating the development of genome-edited animals. In this study, our research focused on targeting the ACTG1 and MSTN genes in sheep, revealing a threshold phenomenon in electroporation with a voltage tolerance in sheep in vitro fertilization (IVF) zygotes. Various poring voltages near 40 V and pulse durations were examined for electroporating sheep zygotes. The study concluded that stronger electric fields required shorter pulse durations to achieve the optimal conditions for high gene mutation rates and reasonable blastocyst development. This investigation also assessed the quality of Cas9/sgRNA ribonucleoprotein complexes (Cas9 RNPs) and their influence on genome editing efficiency in sheep early embryos. It was highlighted that pre-complexation of Cas9 proteins with single-guide RNA (sgRNA) before electroporation was essential for achieving a high mutation rate. The use of suitable electroporation parameters for sheep IVF zygotes led to significantly high mutation rates and heterozygote ratios. By delivering Cas9 RNPs and single-stranded oligodeoxynucleotides (ssODNs) to zygotes through electroporation, targeting the MSTN (Myostatin) gene, a knock-in efficiency of 26% was achieved. The successful generation of MSTN-modified lambs was demonstrated by delivering Cas9 RNPs into IVF zygotes via electroporation.

Exploring the Impact of Astaxanthin Supplementation in Conjunction with a 12-Week CrossFit Training Regimen on Selected Adipo-Myokines Levels in Obese Males.

OBJECTIVE: Obesity is associated with an exacerbated metabolic condition that is mediated through impairing balance in the secretion of some adipo-myokines. Therefore, the objective of the present study was to explore the impact of astaxanthin supplementation in conjunction with a 12-week CrossFit training regimen on some selected adipo-myokines, insulin insensitivity, and serum lipid levels in obese males. MATERIAL AND METHODS: This study is a randomized control trial design; 60 obese males were randomly divided into four groups of 15, including the control group (CG), supplement group (SG), training group (TG), and combined training and supplement group (TSG). The participants were subjected to 12 weeks of astaxanthin (AST) supplementation [20 mg/d capsule, once/d] or CrossFit training or a combination of both interventions. The training regimen comprised 36 sessions of CrossFit, each lasting 60 min, conducted three times per week. The metabolic indices, body composition, anthropometrical, cardio-respiratory, and also some plasma adipo-myokine factors, including decorin (DCN), activin A, myostatin (MST), transforming growth factor (TGF)-ß1, and follistatin (FST), were examined 12 and 72 h before the initiation of the main interventional protocols, and then 72 h after the final session of the training protocol. RESULTS: There was no significant difference in the baseline data between the groups (p > 0.05). There were significant interactions between group x time for DCN (η2 = 0.82), activin A (η2 = 0.50), FST (η2 = 0.92), MST (η2 = 0.75), and TGFB-1 (η2 = 0.67) (p < 0.001 for all the variables). Significantly changes showed for DCN in TSG compared to TG and SG and also TG compared to SG (p = 0.0001); for activin A in SG compared to TG (p = 0.01) and TSG (p = 0.002); for FST in SG compared to TG and TSG (p = 0.0001), also in TSG compared to TG (p = 0.0001); for MST in SG, TG, and TSG compared to CG (p = 0.0001) and also in TSG compared to SG (p = 0.0001) and TG (p = 0.001); for TGFB-1 in SG, TG, and TSG compared to CG (p = 0.0001) and also TSG compared to SG (p = 0.0001) and TG (p = 0.001). CONCLUSIONS: The 12-week CrossFit training concurrent with AST supplementation reduced anthropometric and metabolic factors and also serum lipid levels while producing positive changes in body composition and cardiovascular factors. Increased FST and DCN and reduced activin A, MST, and TGF-ß1 were other affirmative responses to both interventions.

New Insight in Using of Mesenchyme Stem Cell Conditioning Medium for the Impaired Muscle related Biomarkers: In vivo Study with Rat Model.

AIMS AND OBJECTIVES: This study aimed to investigate the effects of Umbilical Cord Mesencymal Stem Cell Conditioning Medium (UC MSC-CM) administration on body weight recovery and the level of four molecular biomarkers, namely Superoxide Dismutase (SOD), vascular Endothelial Growth Factor (VEGF), C-Reactive Protein (CRP), and myostatin. MATERIALS AND METHODS: Secretome was injected intramuscularly twice at 1.5 mL (day 7 and 14) into the right thigh of high-dose, short-term galactose-induced aging rats. The data of day 7 (before) and day 21 (after the administration) were evaluated. The body weights and the four biomarkers were measured before (day 7) and after intervention (day 21). RESULTS: This study showed that the UC MSC-CM intramuscular administrations did not influence body weight regeneration. However, it could increase SOD and VEGF levels and decrease CRP and myostatin levels. CONCLUSION: Treatment with UC MSC-CM is a promising and potential agent in treating sarcopenia.

Résumé Buts et objectifs:Cette étude visait à examiner les effets de l'administration d'un milieu de conditionnement de cellules souches mésencéphaliques de cordon ombilical (UC MSC-CM) sur la récupération du poids corporel et le niveau de quatre biomarqueurs moléculaires, à savoir la superoxyde dismutase (SOD), le facteur de croissance endothéliale vasculaire (VEGF), la protéine C-réactive (CRP) et la myostatine.Matériels et méthodes:Le sécrétome (UC MSC-CM) a été injecté par voie intramusculaire deux fois à 1,5 ml (jour 7 et 14) dans la cuisse droite de rats vieillissant à forte dose et à court terme induits par le galactose. Les données du jour 7 (avant) et du jour 21 (après l'administration) ont été évaluées. Le poids corporel et les quatre biomarqueurs ont été mesurés avant (jour 7) et après l'intervention (jour 21).Résultats:Cette étude a montré que les administrations intramusculaires de CSM-CM d'UC n'ont pas influencé la régénération du poids corporel. Cependant, elle a pu augmenter les niveaux de SOD et de VEGF et diminuer les niveaux de CRP et de myostatine.Conclusion:Le traitement par UC MSC-CM est un agent prometteur et potentiel dans le traitement de la sarcopénie.

Impact of combined intermittent fasting and high-intensity interval training on apoptosis and atrophy signaling in rat fast- and slow-twitch muscles.

This study aimed to evaluate the influence of combined intermittent fasting (IF) and high-intensity interval training (HIIT) on morphology, caspase-independent apoptosis signaling pathway, and myostatin expression in soleus and gastrocnemius (white portion) muscles from healthy rats. Sixty-day-old male Wistar rats (n = 60) were divided into four groups: control (C), IF, high-intensity-interval training (T), and high-intensity-interval training and intermittent fasting (T-IF). The C and T groups received ad libitum chow daily; IF and T-IF received the same standard chow every other day. Animals from T and T-IF underwent a HIIT protocol five times a week for 12 weeks. IF reduced gastrocnemius mass and increased pro-apoptotic proteins apoptosis-inducing factor (AIF) and endonuclease G (EndoG) in soleus and cleaved-to-non-cleaved PARP-1 ratio and myostatin expression in gastrocnemius white portion. HIIT increased AIF and apoptosis repressor with caspase recruitment domain expression in soleus and cleaved-to-total PARP-1 ratio in gastrocnemius muscle white portion. The combination of IF and HIIT reduced fiber cross-sectional area in both muscles, increased EndoG and AIF expression, and decreased cleaved-to-non-cleaved PARP-1 ratio in gastrocnemius muscle white portion. Muscle responses to IF and HIIT are directly impacted by the muscle fiber type composition and are modulated, at least in part, by myostatin and caspase-independent apoptosis signaling.

Adipokines and Myokines as Markers of Malnutrition and Sarcopenia in Patients Receiving Kidney Replacement Therapy: An Observational, Cross-Sectional Study.

Chronic kidney disease (CKD) is linked to an elevated risk of malnutrition and sarcopenia, contributing to the intricate network of CKD-related metabolic disorders. Adipokines and myokines are markers and effectors of sarcopenia and nutritional status. The aim of this study was to assess whether the adipokine-myokine signature in patients on kidney replacement therapy could help identify malnutrition and sarcopenia. The study involved three groups: 84 hemodialysis (HD) patients, 44 peritoneal dialysis (PD) patients, and 52 kidney transplant recipients (KTR). Mean age was 56.1 ± 16.3 years. Malnutrition was defined using the 7-Point Subjective Global Assessment (SGA) and the Malnutrition-Inflammation Score (MIS). Sarcopenia was diagnosed based on reduced handgrip strength (HGS) and diminished muscle mass. Concentrations of adipokines and myokines were determined using the enzyme-linked immunosorbent assay (ELISA). 32.8% of all study participants were identified as malnourished and 20.6% had sarcopenia. For malnutrition, assessed using the 7-Point SGA, in ROC analysis albumin (area under the curve (AUC) 0.67 was the best single biomarker identified. In dialysis patients, myostatin (AUC 0.79) and IL-6 (AUC 0.67) had a high discrimination value for sarcopenia, and we were able to develop a prediction model for sarcopenia, including age, albumin, adiponectin, and myostatin levels, with an AUC of 0.806 (95% CI: 0.721-0.891). Adipokines and myokines appear to be useful laboratory markers for assessing malnutrition and sarcopenia. The formula we propose could contribute to a better understanding of sarcopenia and potentially lead to more effective interventions and management strategies for dialysis patients.

Increased nanosphere size in the cuticle layer of Japanese quail egg by mutation in the myostatin gene.

Cuticle quality can affect food safety by protecting poultry eggs from bacterial infection in the modern poultry industry. However, genetic factors related to cuticle nanostructure are not much reported due to limited bird models. In the current study, the genome-edited quail targeting myostatin (MSTN) gene was used to investigate the effect of MSTN mutation on the cuticle nanostructure and quality. To analyze nanostructure of the cuticle layer of the MSTN mutant and wild-type (WT) quail eggs, scanning electron microscope (SEM) images was taken. Thickness of the cuticle layer did not differ between the MSTN mutant and WT groups, but the size of the nanospheres in the surface of the cuticle layer was increased by MSTN mutation. In addition, increased size of the nanospheres in the MSTN mutant group was also shown in the upper region of the cross-sectional cuticle layer. Notably, both groups showed similar small-sized nanospheres in the lower region of the cuticle layer and the size was increased as they ascended to the upper region. The data suggested that MSTN mutation increased the size of the nanosphere in the upper region of the cuticle layer at a late phase rather than increasing the size of nanospheres in the lower region of the cuticle layer at an early phase of cuticle formation. However, the number of Escherichia coli attached to the surface did not differ between the two groups indicating no association between nanosphere size and bacterial attachment in quail eggs. The current study demonstrated a new function of the MSTN gene on regulation of cuticle nanostructure, for the first time. These results advanced our knowledge on the association between genetic factors and cuticle nanostructure and can be served as a reference to study the mechanism of cuticle formation in the future study.

A molecular pathway for cancer cachexia-induced muscle atrophy revealed at single-nucleus resolution.

Cancer cachexia is a prevalent and often fatal wasting condition that cannot be fully reversed with nutritional interventions. Muscle atrophy is a central component of the syndrome, but the mechanisms whereby cancer leads to skeletal muscle atrophy are not well understood. We performed single-nucleus multi-omics on skeletal muscles from a mouse model of cancer cachexia and profiled the molecular changes in cachexic muscle. Our results revealed the activation of a denervation-dependent gene program that upregulates the transcription factor myogenin. Further studies showed that a myogenin-myostatin pathway promotes muscle atrophy in response to cancer cachexia. Short hairpin RNA inhibition of myogenin or inhibition of myostatin through overexpression of its endogenous inhibitor follistatin prevented cancer cachexia-induced muscle atrophy in mice. Our findings uncover a molecular basis of muscle atrophy associated with cancer cachexia and highlight potential therapeutic targets for this disorder.

Establishment of CRISPR-Cas9 ribonucleoprotein mediated MSTN gene edited pregnancy in buffalo: Compare cells transfection and zygotes electroporation.

Genome editing is recognized as a powerful tool in agriculture and research, enhancing our understanding of genetic function, diseases, and productivity. However, its progress in buffaloes has lagged behind other mammals due to several challenges, including long gestational periods, single pregnancies, and high raising costs. In this study, we aimed to generate MSTN-edited buffaloes, known for their distinctive double-muscling phenotype, as a proof of concept. To meet our goal, we used somatic cell nuclear transfer (SCNT) and zygotic electroporation (CRISPR-EP) technique. For this, we firstly identified the best transfection method for introduction of RNP complex into fibroblast which was further used for SCNT. For this, we compared the transfection, cleavage efficiency and cell viability of nucleofection and lipofection in adult fibroblasts. The cleavage, transfection efficiency and cell viability of nucleofection group was found to be significantly (P ≤ 0.05) higher than lipofection group. Four MSTN edited colony were generated using nucleofection, out of which three colonies was found to be biallelic and one was monoallelic. Further, we compared the efficacy, embryonic developmental potential and subsequent pregnancy outcome of SCNT and zygotic electroporation. The blastocyst rate of electroporated group was found to be significantly (P ≤ 0.05) higher than SCNT group. However, the zygotic electroporation group resulted into two pregnancies which were confirmed to be MSTN edited. Since, the zygotic electroporation does not require complex micromanipulation techniques associated with SCNT, it has potential for facilitating the genetic modification in large livestock such as buffaloes. The present study lays the basis for inducing genetic alternation with practical or biological significance.

[Effects of thunder-fire moxibustion on balance function and musculoskeletal metabolism in female patients of primary osteoporosis with low muscle mass].

OBJECTIVE: To observe the effects of thunder-fire moxibustion on the balance function and musculoskeletal metabolism in female patients of primary osteoporosis (POP) with low muscle mass. METHODS: Sixty female patients of POP with low muscle mass were randomly divided into an observation group (30 cases, 5 cases dropped out) and a control group (30 cases, 2 cases dropped out). The patients in the control group were treated with oral administration of Caltrate D (1.5 g calcium carbonate + 125 IU vitamin D3), one tablet per day for 12 weeks. In addition to the control treatment, the patients in the observation group were treated with thunder-fire moxibustion at Mingmen (GV 4), Yaoyangguan (GV 3), bilateral Ganshu (BL 18), Shenshu (BL 23), and Dachangshu (BL 25), 30 min per acupoint, once every other day, three times a week, for 12 weeks. Balance function indexes (95% confidence ellipse area of the center of pressure [COP], total displacement, average speed), lumbar pain visual analogue scale (VAS), serum muscle metabolism factors (myostatin [MSTN], peroxisome proliferator-activated receptor γ coactivator-1α [PGC-1α]) and bone metabolism factors (aminoterminal propeptide typeⅠ procollagen [PINP], C-terminal telopeptide of typeⅠcollagen [CTX-Ⅰ]) were compared before and after treatment in both groups. RESULTS: Compared before treatment, the 95% confidence ellipse area of COP, total displacement, and average speed in the observation group were decreased after treatment (P<0.01), and the above indexes in the observation group were lower than those in the control group (P<0.05). Compared before treatment, the VAS scores in both groups were decreased after treatment (P<0.01), the score in the observation group was lower than that in the control group (P<0.01). Compared before treatment, the serum levels of MSTN, PINP and CTX-Ⅰ in the observation group were reduced after treatment (P<0.01), while the serum level of PGC-1α was increased (P<0.01). The control group showed a decrease in serum level of MSTN (P<0.05). The observation group had lower serum levels of MSTN and PINP (P<0.05) and higher serum level of PGC-1α (P<0.01) compared to the control group. CONCLUSION: The thunder-fire moxibustion can effectively relieve lumbar pain, improve balance function, and regulate musculoskeletal metabolism in female patients of POP with low muscle mass.

IGF-1 and myostatin-mediated co-regulation in skeletal muscle and bone of Daurian ground squirrels (Spermophilus dauricus) during different hibernation stages.

Muscle and bone are cooperatively preserved in Daurian ground squirrels (Spermophilus dauricus) during hibernation. As such, we hypothesized that IGF-1 and myostatin may contribute to musculoskeletal maintenance during this period. Thus, we systematically assessed changes in the protein expression levels of IGF-1 and myostatin, as well as their corresponding downstream targets, in the vastus medialis (VM) muscle and femur in Daurian ground squirrels during different stages. Group differences were determined using one-way analysis of variance (ANOVA). Results indicated that the co-localization levels of IGF-1 and its receptor (IGF-1R) increased by 50% during the pre-hibernation period (PRE) and by 35% during re-entry into torpor (RET) compared to the summer active period (SA). The phosphorylation level of FOXO1 in the VM muscle increased by 50% in the torpor (TOR) group and by 82% in the inter-bout arousal (IBA) group compared to the PRE group. The phosphorylation level of SGK-1 increased by 54% in the IBA group and by 62% in the RET group compared to the SA group. In contrast, the protein expression of IGF-1 and phosphorylation levels of PI3K, Akt, mTOR, and GSK3ß in the VM muscle showed no obvious differences among the different groups. ß-catenin protein expression was up-regulated by 84% in the RET group compared to the SA group, while the content of IGF-1 protein, correlation coefficients of IGF-1 and IGF-1R, and phosphorylation levels of PI3K, Akt, and GSK3ß in the femur showed no significant differences among groups. Regarding myostatin and its downstream targets, myostatin protein expression decreased by 70% in the RET group compared to the SA group, whereas ActRIIB protein expression and Smad2/3 phosphorylation in the VM muscle showed no obvious differences among groups. Furthermore, Smad2/3 phosphorylation decreased by 58% in the TOR group and 53% in the RET group compared to the SA group, whereas ActRIIB protein expression in the femur showed no obvious differences among groups. Overall, the observed changes in IGF-1 and myostatin expression and their downstream targets may be involved in musculoskeletal preservation during hibernation in Daurian ground squirrels.

Swimming in cold water increases the browning process by diminishing the Myostatin pathway.

BACKGROUND: Brown adipose tissue (BAT) is a thermogenic tissue that uncouples oxidative phosphorylation from ATP synthesis and increases energy expenditure via non-shivering thermogenesis in mammals. Cold exposure and exercise have been shown to increase BAT and browning of white adipose tissue (WAT) in mice. This study aimed to determine whether there is an additive effect of exercise during cold exposure on markers related to browning of adipose tissue. in Wistar rats. METHODS: Twenty-four male Wistar rats were randomly divided into three groups: Control (C, 25˚C), Swimming in Neutral (SN, 30˚C) water, and Swimming in Cold (SC, 15˚C) water. Swimming included intervals of 2-3 min, 1 min rest, until exhausted, three days a week for six weeks, with a training load of 3-6% body weight. After the experimental protocol, interscapular BAT and inguinal subcutaneous white adipose tissue (WAT) were excised, weighed, and processed for beiging marker gene expression. RESULTS: SN and SC resulted in lower body weight gain, associated with reduced WAT and BAT volume and increased BAT number with greater effects observed in SC. Myostatin protein expression was lower in BAT, WAT, soleus muscle, and serum NC and SC compared to the C group. Expression of the interferon regulatory factor-4 (IRF4) gene in both BAT and WAT tissues was significantly greater in the SC than in the C. Expression of the PGC-1α in BAT was significantly increased in the SC compared to C and increased in WAT in NC and SC. Expression of the UCP1 in BAT and WAT increased in the SC group compared to other groups. CONCLUSION: The findings demonstrate that six weeks of swimming training in cold water promotes additive effects of the expression of genes and proteins involved in the browning process of adipose tissue in Wistar rats. Myostatin inhibition may possess a regulator effect on the PGC-1α - UCP1 pathway that mediates adipose tissue browning.

Transglutaminase-catalyzed covalent anti-myostatin peptide depots.

Nature realizes protein and peptide depots by catalyzing covalent bonds with the extracellular matrix (ECM) of tissues. We are translating this natural blueprint for the sustained delivery of a myostatin-inhibiting peptide (Anti-Myo), resulting in an enzyme depot established from injectable solutions. For that, we fused Anti-Myo to the D-domain of insulin-like growth factor I, a transglutaminase (TG) substrate. TG catalyzed the covalent binding of the D-domain to ECM proteins, such as laminin and fibronectin, on bioengineered ECM and in mice. ECM decorated with Anti-Myo suppressed myostatin activity and pathway activation and reduced the differentiation of preconditioned bone marrow-derived macrophages into osteoclasts in vitro.

Myostatin's marvels: From muscle regulator to diverse implications in health and disease.

Myostatin, a member of the transforming growth factor-ß superfamily, is a pivotal regulator of skeletal muscle growth in mammals. Its discovery has sparked significant interest due to its multifaceted roles in various physiological processes and its potential therapeutic implications. This review explores the diverse functions of myostatin in skeletal muscle development, maintenance and pathology. We delve into its regulatory mechanisms, including its interaction with other signalling pathways and its modulation by various factors such as microRNAs and mechanical loading. Furthermore, we discuss the therapeutic strategies aimed at targeting myostatin for the treatment of muscle-related disorders, including cachexia, muscular dystrophy and heart failure. Additionally, we examine the impact of myostatin deficiency on craniofacial morphology and bone development, shedding light on its broader implications beyond muscle biology. Through a comprehensive analysis of the literature, this review underscores the importance of further research into myostatin's intricate roles and therapeutic potential in human health and disease.

Impact of Disease Severity and Disease-Modifying Therapies on Myostatin Levels in SMA Patients.

Clinical trials with treatments inhibiting myostatin pathways to increase muscle mass are currently ongoing in spinal muscular atrophy. Given evidence of potential myostatin pathway downregulation in Spinal Muscular Atrophy (SMA), restoring sufficient myostatin levels using disease-modifying treatments (DMTs) might arguably be necessary prior to considering myostatin inhibitors as an add-on treatment. This retrospective study assessed pre-treatment myostatin and follistatin levels' correlation with disease severity and explored their alteration by disease-modifying treatment in SMA. We retrospectively collected clinical characteristics, motor scores, and mysotatin and follistatin levels between 2018 and 2020 in 25 Belgian patients with SMA (SMA1 (n = 13), SMA2 (n = 6), SMA 3 (n = 6)) and treated by nusinersen. Data were collected prior to treatment and after 2, 6, 10, 18, and 30 months of treatment. Myostatin levels correlated with patients' age, weight, SMA type, and motor function before treatment initiation. After treatment, we observed correlations between myostatin levels and some motor function scores (i.e., MFM32, HFMSE, 6MWT), but no major effect of nusinersen on myostatin or follistatin levels over time. In conclusion, further research is needed to determine if DMTs can impact myostatin and follistatin levels in SMA, and how this could potentially influence patient selection for ongoing myostatin inhibitor trials.

CRISPR-Cas guide RNA indel analysis using CRISPResso2 with Nanopore sequencing data.

OBJECTIVE: Insertion and deletion (indel) analysis of CRISPR-Cas guide RNAs (gRNAs) is crucial in gene editing to assess gRNA efficiency and indel frequency. This study evaluates the utility of CRISPResso2 with Oxford Nanopore sequencing data (nCRISPResso2) for gRNA indel screening, compared to two common Sanger sequencing-based methods, TIDE and ICE. To achieve this, sheep and horse fibroblasts were transfected with Cas9 and a gRNA targeting the myostatin (MSTN) gene. DNA was subsequently extracted, and PCR products exceeding 600 bp were sequenced using both Sanger and Nanopore sequencing. Indel profiling was then conducted using TIDE, ICE, and nCRISPResso2. RESULTS: Comparison revealed close correspondence in indel formation among methods. For the sheep MSTN gRNA, indel percentages were 52%, 58%, and 64% for TIDE, ICE, and nCRISPResso2, respectively. Horse MSTN gRNA showed 81%, 87%, and 86% edited amplicons for TIDE, ICE, and nCRISPResso2. The frequency of each type of indel was also comparable among the three methods, with nCRISPResso2 and ICE aligning the closest. nCRISPResso2 offers a viable alternative for CRISPR-Cas gRNA indel screening, especially with large amplicons unsuitable for Illumina sequencing. CRISPResso2's compatibility with Nanopore data enables cost-effective and efficient indel profiling, yielding results comparable to common Sanger sequencing-based methods.

Genetic Variations of MSTN and Callipyge in Tibetan Sheep: Implications for Early Growth Traits.

Tibetan sheep are vital to the ecosystem and livelihood of the Tibetan Plateau; however, traditional breeding methods limit their production and growth. Modern molecular breeding techniques are required to improve these traits. This study identified a single nucleotide polymorphism (SNP) in myostatin (MSTN) and Callipyge in Tibetan sheep. The findings indicated notable associations between MSTN genotypes and growth traits including birth weight (BW), body length (BL), chest width (ChW), and chest circumference (ChC), as well as a particularly strong association with cannon circumference (CaC) at 2 months of age. Conversely, Callipyge polymorphisms did not have a significant impact on Tibetan sheep. Moreover, the analyses revealed a significant association between sex and BW or hip width (HW) at 2 months of age and ChW, ChC, and CaC at 4 months of age. Furthermore, the study's results suggested that the genotype of MSTN as a GA was associated with a notable sex effect on BW, while the genotype of Callipyge (CC) showed a significant impact of sex on CaC at 2 months of age. These results indicated that the SNP of MSTN could potentially serve as a molecular marker for early growth traits in Tibetan sheep.

Effects of weight loss rate on myostatin and follistatin dynamics in patients with obesity.

Background: Exercise-induced cytokines involved in controlling body composition include myostatin (MST) and follistatin (FST), both of which are influenced by physical activity. This study investigated changes in body composition and physical activity during a weight loss program, as well as the impact on serum MST and FST levels at various weight loss rates. Methods: A total of 126 patients with obesity who completed a 6-month weight loss program were divided into three groups based on weight loss rate (%): low (< 3%), middle (3-10%), and high (≥10%). The International Physical Activity Questionnaire was used for assessing physical activity, whereas dual X-ray absorptiometry was used to determine body composition. Serum MST and FST levels were measured using the enzyme-linked immunosorbent assay. Results: The middle and high groups showed a significant decrease in percent body fat and a significant increase in percent lean body mass and physical activity. Serum MST levels increased significantly in all three groups, although FST levels reduced significantly only in the middle group. After adjusting for sex and body composition, changes in peak oxygen intake (ß = -0.359) and serum FST levels (ß = -0.461) were identified as independent factors for the change in MST levels in the low group. Sex (ß = -0.420) and changes in MST levels (ß = -0.525) were identified as independent factors for the change in serum FST levels in the low group, whereas in the high group, sitting time (ß = -0.600) during the weight loss program was identified as an independent factor for change in serum FST levels. Conclusion: Serum MST levels in patients with obesity increased significantly following the weight loss program, independent of weight loss rate. In contrast, serum FST levels reduced significantly only in the 3-10% weight loss group. These findings indicate that MST and FST secretion dynamics may fluctuate in response to physical activity, while also reflecting feedback regulation of body composition and metabolism during weight reduction.

Serum Myostatin is Associated With Central-to-Peripheral Arterial Stiffness Gradient in Healthy Adolescents: The MACISTE Study.

BACKGROUND: Myostatin is a protein compound, structurally related to the transforming growth factor-beta protein, which plays a pivotal role in regulating muscle growth and extracellular matrix production. It exerts both profibrotic and antihypertrophic effects on vascular smooth muscle cells. Aim of the study was to explore the potential association between serum myostatin levels (sMSTN) and carotid-femoral pulse wave velocity (cf-PWV), carotid-radial pulse wave velocity (cr-PWV), and their ratio (PWVr), in a cohort of healthy adolescents. METHODS: A cohort of 128 healthy subjects (mean age 17 ±â€…2 years, 59% male) was randomly selected from participants to the MACISTE (Metabolic And Cardiovascular Investigation at School, TErni) study. sMSTN was assessed utilizing an enzyme-linked immunosorbent assay. PWVs were measured in the supine position using high-fidelity applanation tonometry. RESULTS: The mean cf-PWV was 5.1 ±â€…0.9 m/s, cr-PWV was 6.9 ±â€…0.9 m/s, and PWVr was 0.75 ±â€…0.12. PWVr exhibited a linear increase across increasing quartiles of sMSTN (0.71 ±â€…0.1, 0.74 ±â€…0.1, 0.7 ±â€…0.1, 0.77 ±â€…0.1, P for trend = 0.03), whereas the association between sMSTN and each single component of PWVr (cf-PWV, cr-PWV) did not attain statistical significance. Quartiles of sMSTN displayed a positive trend with serum HDL-cholesterol (P = 0.01) and a negative one with LDL-cholesterol (P = 0.01). In a multivariate linear model, the association between PWVr and sMSTN was independent of SBP values, age, sex, heart rate, BMI, HDL-cholesterol, and HOMA Index. CONCLUSIONS: In healthy adolescents, sMSTN showed independent associations with PWVr, a measure of central-to-peripheral arterial stiffness gradient. sMSTN may exert differential effects on the structural and functional properties of the arterial wall.

Myostatin serum levels depends on age and diet in athletic and no athletic dogs.

Myostatin is a growth factor related to muscular mass atrophy via mTOR pathway inhibition. Mutations in this gene have been correlated with high muscular mass development in different species of mammals, including human and dogs. Different studies have shown that sport practice increases myostatin gene expression. Some of them were conducted in canine breeds selected for different sport practices, including mushing sports. In this study, body weight, muscular mass, and serum levels of myostatin were analysed in different canine breeds, selected, and not selected for sprint and middle-distance racing, and the effect on epidemiological factors was evaluated. Sex, reproductive status, and canine breed affects body weight and muscular mass, being higher in males, and in sled canine breed. Age has an effect in body weight and myostatin serum levels, being lower in elder dogs. Sport practice and type of diet had an effect in muscular mass development but not in myostatin serum levels. Results showed a high positive correlation between muscular mass and body weight but not with myostatin levels. These results suggest that independent-myostatin mechanisms of mTOR pathway regulation could be related to muscular mass development in dogs.