Prolonged underfeeding of sheep increases myostatin and myogenic regulatory factor Myf-5 in skeletal muscle while IGF-I and myogenin are repressed

The IGF axis is nutritionally sensitive in vivo and IGFs stimulate myoblast proliferation and differentiation in vitro, while myostatin inhibits these processes in vitro. We hypothesised that underfeeding would reversibly inhibit the myogenic activity of satellite cells in vivo together with decreased IGF-I and increased myostatin in muscle. Satellite cell activity was measured indirectly from the expression of proliferating cell nuclear antigen (PCNA) and the myogenic regulatory factors (MRFs), MyoD, Myf-5 and myogenin. Young sheep were underfed (30% of maintenance) and some killed after 1, 4, 12, 17, 21 and 22 weeks. Remaining underfed animals were then re-fed a control ration of pellets and killed after 2 days, and 1, 6 and 30 weeks. Expression of PCNA and MRFs decreased during the first week of underfeeding. This coincided with reduced IGF-I and myostatin mRNA, and processed myostatin. Subsequently, Myf-5, MyoD, myostatin mRNA and processed myostatin increased, suggesting that satellite cells may have become progressively quiescent. Long-term underfeeding caused muscle necrosis in some animals and IGF-I and MRF expression was increased in these, indicating the activation of satellite cells for muscle repair. Re-feeding initiated rapid muscle growth and increased expression of PCNA, IGF-I and the MRFs concurrently with decreased myostatin proteins. In conclusion, these data indicate that IGF-I and myostatin may work in a coordinated manner to regulate the proliferation, differentiation and quiescence of satellite cells in vivo.

Download Full-text

miR-194-5p negatively regulates the proliferation and differentiation of rabbit skeletal muscle satellite cells

Molecular and Cellular Biochemistry ◽

10.1007/s11010-020-03918-0 ◽

2020 ◽

Author(s):

Yu Shi ◽

Xudong Mao ◽

Mingcheng Cai ◽

Shenqiang Hu ◽

Xiulan Lai ◽

...

Keyword(s):

Skeletal Muscle ◽

Satellite Cells ◽

Mammalian Species ◽

Muscle Growth ◽

Luciferase Reporter ◽

Stem Cell Population ◽

Muscle Satellite Cells ◽

Skeletal Muscle Satellite Cells ◽

Proliferation And Differentiation

Abstract Skeletal muscle satellite cells (SMSCs), also known as a multipotential stem cell population, play a crucial role during muscle growth and regeneration. In recent years, numerous miRNAs have been associated with the proliferation and differentiation of SMSCs in a number of mammalian species; however, the regulatory mechanisms of miR-194-5p in rabbit SMSCs still remain scarce. In this study, miR-194-5p was first observed to be highly expressed in the rabbit leg muscle. Furthermore, both the mimics and inhibitor of miR-194-5p were used to explore its role in the proliferation and differentiation of rabbit SMSCs cultured in vitro. Results from both EdU and CCK8 assays showed that miR-194-5p inhibited the proliferation of SMSCs. Meanwhile, Mef2c was identified as a target gene of miR-194-5p based on the dual-luciferase reporter assay results. In addition, upregulation of miR-194-5p decreased the expression levels of Mef2c and MyoG during rabbit SMSCs differentiation on Days 3 and 7 of in vitro culture. Taken together, these data demonstrated that miR-194-5p negatively regulates the proliferation and differentiation of rabbit SMSCs by targeting Mef2c.

Download Full-text

Srf controls satellite cell fusion through the maintenance of actin architecture

The Journal of Cell Biology ◽

10.1083/jcb.201705130 ◽

2017 ◽

Vol 217 (2) ◽

pp. 685-700 ◽

Cited By ~ 20

Author(s):

Voahangy Randrianarison-Huetz ◽

Aikaterini Papaefthymiou ◽

Gaëlle Herledan ◽

Chiara Noviello ◽

Ulduz Faradova ◽

...

Keyword(s):

Actin Cytoskeleton ◽

Serum Response Factor ◽

Control Cell ◽

Muscle Growth ◽

Muscle Stem Cells ◽

Hypertrophic Growth ◽

Proliferation And Differentiation ◽

Muscle Homeostasis

Satellite cells (SCs) are adult muscle stem cells that are mobilized when muscle homeostasis is perturbed. Here, we show that serum response factor (Srf) is needed for optimal SC-mediated hypertrophic growth. We identified Srf as a master regulator of SC fusion required in both fusion partners, whereas it was dispensable for SC proliferation and differentiation. We show that SC-specific Srf deletion leads to impaired actin cytoskeleton and report the existence of finger-like actin–based protrusions at fusion sites in vertebrates that were notoriously absent in fusion-defective myoblasts lacking Srf. Restoration of a polymerized actin network by overexpression of an α-actin isoform in Srf mutant SCs rescued their fusion with a control cell in vitro and in vivo and reestablished overload-induced muscle growth. These findings demonstrate the importance of Srf in controlling the organization of actin cytoskeleton and actin-based protrusions for myoblast fusion in mammals and its requirement to achieve efficient hypertrophic myofiber growth.

Download Full-text

Comparative analysis of cattle breeds as satellite cells donors for cultured beef

10.1101/2022.01.14.476358 ◽

2022 ◽

Author(s):

Lea Melzener ◽

Shijie Ding ◽

Rui Hueber ◽

Tobias Messmer ◽

Guanghong Zhou ◽

...

Keyword(s):

Satellite Cells ◽

Myogenic Differentiation ◽

Muscle Growth ◽

Meat Production ◽

Phenotypic Traits ◽

Welfare Benefits ◽

Cultured Meat ◽

Cattle Breeds

Background: Cultured meat is a promising new field with the potential for considerable environmental and animal welfare benefits. One technological approach to cultured meat production utilises the proliferative and differentiative capacity of muscle-derived satellite cells (SCs) to produce large volumes of cultured muscle tissue from small biopsies of donor animals. Differing genotypes between cattle breeds lead to predictable phenotypic traits, resulting in breeds being favoured for their respective meat or milk production characteristics in the livestock industry. However, whilst these breeds show significant differences in muscle growth, it is unclear whether the physiological differences observed between them in vivo are reflected in differences in SC behaviour in vitro, particularly with respect to proliferation, differentiation and cellular longevity, and hence whether particular breeds might represent preferred SC donors for a cultured beef bioprocess. Results: Comparing SCs isolated from five breeds (Belgian Blue, Holstein Friesian, Galloway, Limousin and Simmental), we found that the proliferation rates were largely unaffected by the donor breed. In contrast, potentially meaningful differences were observed in the kinetics and extent of myogenic differentiation. Furthermore, whilst differentiation dropped for all breeds with increasing population doublings (PDs), SCs from Belgian Blue and Limousin cattle showed significantly longer retention of differentiation capacity over long-term passaging. Conclusion: SCs from all breeds were able to proliferate and differentiate, although Limousin and (particularly) Belgian Blue cattle, both breeds commonly used for traditional meat production, may represent preferred donors for cultured beef production.

Download Full-text

Exogenous Expression of an Alternative Splicing Variant of Myostatin Prompts Leg Muscle Fiber Hyperplasia in Japanese Quail

International Journal of Molecular Sciences ◽

10.3390/ijms20184617 ◽

2019 ◽

Vol 20 (18) ◽

pp. 4617 ◽

Cited By ~ 1

Author(s):

Paula Renee Chen ◽

Yeunsu Suh ◽

Sangsu Shin ◽

Rachel Marie Woodfint ◽

Seongsoo Hwang ◽

...

Keyword(s):

Skeletal Muscle ◽

Alternative Splicing ◽

Japanese Quail ◽

Muscle Development ◽

Pectoralis Major Muscle ◽

Muscle Growth ◽

Cross Sectional ◽

Proliferation And Differentiation

Myostatin (MSTN) negatively regulates muscle growth and development through inhibiting myoblast proliferation and differentiation. Five alternative splicing isoforms of MSTN (MSTN-A to MSTN-E) have been discovered in domestic avian species. MSTN-A has high expression in skeletal muscle and encodes the full-length peptide with anti-myogenic activity. Another isoform, MSTN-B, is also highly expressed in skeletal muscle and encodes a truncated peptide that has pro-myogenic capabilities in vitro, which include promoting the proliferation and differentiation of quail muscle precursor cells. The objective of this study was to investigate overexpression of MSTN-B in vivo by using two independent lines of transgenic Japanese quail with expression directed in the skeletal muscle. Unexpectedly, the chicken skeletal muscle alpha actin 1 (cACTA1) promoter resulted in restricted exogenous MSTN-B protein expression to certain skeletal muscles, such as the gastrocnemius and tibialis anterior, but not the pectoralis major muscle. Gastrocnemius weight as a percentage of body weight in transgenic quail was increased compared to non-transgenic quail at posthatch day 21 (D21) and posthatch D42. An increase in the size of the gastrocnemius in transgenic quail was attributed to an increase in fiber number but not fiber cross-sectional area (CSA). During embryonic development, paired box 7 (PAX7) expression was prolonged in the transgenic embryos, but other myogenic regulatory factors (MRFs) were unchanged after MSTN-B overexpression. Taken together, these data provide novel insights into the regulation of skeletal muscle development by alternative splicing mechanisms in avians.

Download Full-text

Mixed lactate and caffeine compound increases satellite cell activity and anabolic signals for muscle hypertrophy

Journal of Applied Physiology ◽

10.1152/japplphysiol.00054.2014 ◽

2015 ◽

Vol 118 (6) ◽

pp. 742-749 ◽

Cited By ~ 32

Author(s):

Yoshimi Oishi ◽

Hayato Tsukamoto ◽

Takumi Yokokawa ◽

Keisuke Hirotsu ◽

Mariko Shimazu ◽

...

Keyword(s):

Satellite Cells ◽

Cell Activity ◽

Treadmill Running ◽

C2c12 Cells ◽

Protein Levels ◽

Low Intensity ◽

Proliferation And Differentiation ◽

Total Dna ◽

Low Intensity Exercise

We examined whether a mixed lactate and caffeine compound (LC) could effectively elicit proliferation and differentiation of satellite cells or activate anabolic signals in skeletal muscles. We cultured C2C12 cells with either lactate or LC for 6 h. We found that lactate significantly increased myogenin and follistatin protein levels and phosphorylation of P70S6K while decreasing the levels of myostatin relative to the control. LC significantly increased protein levels of Pax7, MyoD, and Ki67 in addition to myogenin, relative to control. LC also significantly increased follistatin expression relative to control and stimulated phosphorylation of mTOR and P70S6K. In an in vivo study, male F344/DuCrlCrlj rats were assigned to control (Sed, n = 10), exercise (Ex, n = 12), and LC supplementation (LCEx, n = 13) groups. LC was orally administered daily. The LCEx and Ex groups were exercised on a treadmill, running for 30 min at low intensity every other day for 4 wk. The LCEx group experienced a significant increase in the mass of the gastrocnemius (GA) and tibialis anterior (TA) relative to both the Sed and Ex groups. Furthermore, the LCEx group showed a significant increase in the total DNA content of TA compared with the Sed group. The LCEx group experienced a significant increase in myogenin and follistatin expression of GA relative to the Ex group. These results suggest that administration of LC can effectively increase muscle mass concomitant with elevated numbers of myonuclei, even with low-intensity exercise training, via activated satellite cells and anabolic signals.

Download Full-text

367 Role of skeletal muscle satellite cells in the broiler chicken Wooden Breast myopathy

Journal of Animal Science ◽

10.1093/jas/skaa278.174 ◽

2020 ◽

Vol 98 (Supplement_4) ◽

pp. 95-96

Author(s):

Jessica D Starkey

Keyword(s):

Skeletal Muscle ◽

Meat Quality ◽

Satellite Cells ◽

Critical Role ◽

Muscle Growth ◽

Relative Size ◽

Genetic Selection ◽

Cell Labeling ◽

Myogenic Regulatory Factor

Abstract To meet the huge global demand for chicken meat, the commercial broiler industry has placed tremendous genetic selection pressure on breast meat yield, growth rate, and feed efficiency traits and has made remarkable improvements over the last 30 years. Unfortunately, along with those tremendous improvements has come a severe meat quality defect whose cause has yet to be elucidated. The Wooden (or Woody) Breast (WB) meat quality defect is characterized by visible bulging of the breast fillet with extreme hardness to the touch. The WB phenotype has been characterized by histopathologists as a degenerative myopathy in which excessive fibrotic tissue infiltration occurs. Skeletal muscle stem cells, also called satellite cells (MSC), play a critical role in post-hatch broiler skeletal muscle growth, repair, and maintenance. Yet the relationship between MSC function in high-yielding broilers and the development of the WB myopathy is still not well understood. Recent work using in vivo cell labeling, cryohistology, and immunofluorescence techniques demonstrates that the relative size and mitotic activity of the various MSC and macrophage populations and collagen deposition are altered in WB-affected muscle. Alterations in myogenic regulatory factor, collagen, and pro- and anti-inflammatory cytokine protein expression in WB-affected muscles have also been observed using quantitative fluorescent Western blotting. These data suggest the involvement of aberrant MSC function in the development of WB myopathy. Future work aimed at determining whether the apparent MSC dysfunction in WB-affected broilers is due to an issue with the MSC themselves and/or their environment will be accomplished using a combination of MSC isolation, labeling, transplant, and tracking strategies. Further exploration will also be required to understand how the local cell signaling mechanisms and cell population kinetics are related to the severity and timing of the development of the WB myopathy in today’s fast-growing, high-yielding broilers.

Download Full-text

Uncoupling between proliferation and differentiation of ovine granulosa cells in vitro

Journal of Endocrinology ◽

10.1677/joe.0.1420497 ◽

1994 ◽

Vol 142 (3) ◽

pp. 497-510 ◽

Cited By ~ 14

Author(s):

D Monniaux ◽

C Pisselet ◽

J Fontaine

Keyword(s):

Cell Proliferation ◽

Granulosa Cell ◽

Granulosa Cells ◽

Follicular Growth ◽

Proliferating Cells ◽

Progesterone Secretion ◽

Proliferation And Differentiation ◽

Igf I

Abstract Granulosa cells of ovarian follicles both proliferate and undergo differentiation. In vivo, an inverse relationship between proliferation and steroidogenesis is observed. However, both processes can be enhanced by insulin-like growth factor-I (IGF-I) in vitro. Studies were undertaken in the ewe to understand the mechanisms controlling the balance between proliferation and differentiation in cultured granulosa cells from antral follicles better. For this purpose, granulosa cells from ovine small follicles (1–3 mm in diameter) and large follicles (5–7 mm in diameter) were compared for progesterone secretion, cytochrome P450 side-chain cleavage (P450scc) expression and their proportions of non-proliferating (G0) cells, in response to IGF-I and FSH stimulation in vitro. IGF-I mainly enhanced the proliferation of granulosa cells from small follicles but it strongly increased progesterone secretion and P450scc expression in granulosa cells from large follicles, in synergy with FSH. Blocking granulosa cell proliferation by the administration of colcemid or aphidicolin had no effect or a weak stimulating effect on progesterone secretion. At the beginning of the culture period, the proportion of non-proliferating cells, estimated by continuous [3H]thymidine labelling experiments, was clearly higher in large than in small follicles (91% vs 30%, P<0·001). For both cell types, treatment with IGF-I in vitro reduced the proportion of non-proliferating cells at 72 h of culture (40% vs 70% respectively in IGF-I-stimulated and unstimulated cells from large follicles, P<0·001, and 17% vs 30% respectively in IGF-I-stimulated and unstimulated cells from small follicles, P<0·001). Treatment with FSH had no effect on the proportion of non-proliferating cells. As revealed by immunohistochemistry experiments, IGF-I, in synergy with FSH, clearly increased the percentage of cells expressing P450scc enzyme and the intensity of staining in granulosa cells from large follicles. Unexpectedly, heavily stained cells in mitosis were observed in IGF-I-stimulated cells from large follicles after 96 h of culture, suggesting that dividing cells might also produce progesterone. Overall, these results support the hypothesis that the growth-promoting and the cytodifferentiative effects of IGF-I are clearly distinct. Moreover, they suggest that uncoupling between proliferation and steroidogenesis may occur in cultured ovine granulosa cells. The loss of proliferative activity accompanying terminal follicular growth in vivo could be reversed in vitro. During terminal follicular growth in vivo, the existence of an active mechanism inhibiting granulosa cell proliferation, and unrelated to terminal differentiation, is therefore strongly suspected. Journal of Endocrinology (1994) 142, 497–510

Download Full-text

A Comparison of Exogenous Labels for the Histological Identification of Transplanted Neural Stem Cells

Cell Transplantation ◽

10.3727/096368916x693680 ◽

2017 ◽

Vol 26 (4) ◽

pp. 625-645 ◽

Cited By ~ 2

Author(s):

Francesca J. Nicholls ◽

Jessie R. Liu ◽

Michel Modo

Keyword(s):

Cell Transplantation ◽

In Vivo Studies ◽

Nuclear Antigen ◽

Hoechst 33342 ◽

Cellular Effects ◽

Proliferation And Differentiation ◽

Brdu Labeling ◽

Transplantation Experiments

The interpretation of cell transplantation experiments is often dependent on the presence of an exogenous label for the identification of implanted cells. The exogenous labels Hoechst 33342, 5-bromo-2′-deoxyuridine (BrdU), PKH26, and Qtracker were compared for their labeling efficiency, cellular effects, and reliability to identify a human neural stem cell (hNSC) line implanted intracerebrally into the rat brain. Hoechst 33342 (2 mg/ml) exhibited a delayed cytotoxicity that killed all cells within 7 days. This label was hence not progressed to in vivo studies. PKH26 (5 μM), Qtracker (15 nM), and BrdU (0.2 μM) labeled 100% of the cell population at day 1, although BrdU labeling declined by day 7. BrdU and Qtracker exerted effects on proliferation and differentiation. PKH26 reduced viability and proliferation at day 1, but this normalized by day 7. In an in vitro coculture assay, all labels transferred to unlabeled cells. After transplantation, the reliability of exogenous labels was assessed against the gold standard of a human-specific nuclear antigen (HNA) antibody. BrdU, PKH26, and Qtracker resulted in a very small proportion (<2%) of false positives, but a significant amount of false negatives (~30%), with little change between 1 and 7 days. Exogenous labels can therefore be reliable to identify transplanted cells without exerting major cellular effects, but validation is required. The interpretation of cell transplantation experiments should be presented in the context of the label's limitations.

Download Full-text

Overexpression of Gly56/Gly80/Gly81-Mutant Insulin-Like Growth Factor-Binding Protein-3 in Transgenic Mice

Endocrinology ◽

10.1210/en.2004-0905 ◽

2005 ◽

Vol 146 (3) ◽

pp. 1523-1531 ◽

Cited By ~ 24

Author(s):

Josef V. Silha ◽

Yaoting Gui ◽

Suresh Mishra ◽

Arnold Leckstrom ◽

Pinchas Cohen ◽

...

Keyword(s):

Binding Protein ◽

Serum Levels ◽

Nuclear Antigen ◽

Mouse Strains ◽

Wild Type ◽

Igf I ◽

Independent Effects ◽

Igfbp 3

IGF-independent effects of IGF-binding protein-3 (IGFBP-3) have been demonstrated in vitro; however, the physiological significance of these effects in vivo is unclear. We generated two transgenic (Tg) mouse strains that overexpress a human Gly56/Gly80/Gly81-mutant IGFBP-3 cDNA. This mutant has a markedly reduced affinity for the IGFs, but retains the IGF-independent effects. Serum levels of mutant IGFBP-3 were 156 ± 12 and 400 ± 24 ng/ml in hemizygous mice of strains 5005 and 5012, respectively. When Tg and wild-type mice were compared, there was no reduction in birth weight, litter size, or postnatal growth. Despite differences in transgene expression in various tissues, relative organ weight was similar in Tg and wild-type mice, with exception of brain, where a modest reduction in brain weight was observed in the high-expressing 5012 lineage. There was also a significant reduction in proliferating cell nuclear antigen-staining cells observed in the periventricular region of the developing brain in embryonic d 18 Tg embryos. In the higher expressing 5012 Tg strain, IGF-I and murine IGFBP-3 levels, marker of GH action were increased. Furthermore, there was a positive correlation between mutant IGFBP-3 levels and IGF-I levels and between mutant IGFBP-3 levels and murine IGFBP-3 (P = 0.002 and P < 0.001, respectively). These data indicate that overexpression of mutant IGFBP-3 is not associated with growth retardation. The higher levels of IGF-I and murine IGFBP-3 in the 5012 Tg strain suggest that the growth inhibitory effect of mutant IGFBP-3 may be compensated for by other mechanisms.

Download Full-text

Osseointegrating and phase-oriented micro-arc-oxidized titanium dioxide bone implants

Journal of Applied Biomaterials & Functional Materials ◽

10.1177/22808000211006878 ◽

2021 ◽

Vol 19 ◽

pp. 228080002110068

Author(s):

Hsien-Te Chen ◽

Hsin-I Lin ◽

Chi-Jen Chung ◽

Chih-Hsin Tang ◽

Ju-Liang He

Keyword(s):

Titanium Dioxide ◽

High Surface ◽

Cell Activity ◽

Active Surface ◽

Rutile Phase ◽

Hydroxyl Groups ◽

Bone Implant ◽

Implant System

Here, we present a bone implant system of phase-oriented titanium dioxide (TiO2) fabricated by the micro-arc oxidation method (MAO) on β-Ti to facilitate improved osseointegration. This (101) rutile-phase-dominant MAO TiO2 (R-TiO2) is biocompatible due to its high surface roughness, bone-mimetic structure, and preferential crystalline orientation. Furthermore, (101) R-TiO2 possesses active and abundant hydroxyl groups that play a significant role in enhancing hydroxyapatite formation and cell adhesion and promote cell activity leading to osseointegration. The implants had been elicited their favorable cellular behavior in vitro in the previous publications; in addition, they exhibit excellent shear strength and promote bone–implant contact, osteogenesis, and tissue formation in vivo. Hence, it can be concluded that this MAO R-TiO2 bone implant system provides a favorable active surface for efficient osseointegration and is suitable for clinical applications.

Download Full-text