scholarly journals LOW GLUCOSE ENHANCES THE CYTOPROTECTIVE EFFECT OF METFORMIN AGAINST DOXORUBICIN-INDUCED CYTOTOXICITY

2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S961-S961
Author(s):  
Fathima Ameer ◽  
Xiaomin Zhang ◽  
Gohar Azhar ◽  
Yingni Che ◽  
Jeanne Wei
Keyword(s):  
Mitochondrial Fission ◽  
Pegylated Liposomal Doxorubicin ◽  
C2c12 Cells ◽  
C2c12 Myoblast ◽  
Protective Effects ◽  
Gene Expressions ◽  
Biochemical Alterations ◽  
Low Glucose ◽  
Pre Treatment ◽  
Myoblast Cells

Abstract Metformin, an oral anti-diabetic drug, is currently being investigated for its anti-aging properties and has also been used as adjunct therapy in cancer. Cancer is a disease of aging. Type 2 diabetes is also prevalent in older adults. We wanted to test the hypothesis that metformin could protect normal cells during chemotherapy treatment under different glucose conditions. We used C2C12 myoblast cells to study cellular bioenergetics, variations in gene expressions, and biochemical alterations induced by metformin and pegylated liposomal doxorubicin (L-Doxo) under low glucose (2.7 mM or 50 mg/dL) and normal physiologic glucose (5.5 mM, or 100 mg/dL) conditions. Using confocal microscopy, we noted that treatment of C2C12 cells with 30 µg/mL L-Doxo under low glucose and normal physiologic glucose conditions induced cellular defects. Furthermore, L-Doxo treatment dysregulated the expression of mitochondrial fission and fusion genes, which may influence transformation of the network’s connectivity. L-Doxo treatment significantly reduced mitochondrial oxygen consumption rate (OCR) and extracellular acidification rate (ECAR). However, pre-treatment with 100 nM metformin provided protection against L-Doxo-induced damage and increased cell viability and ATP levels in cells even under low glucose conditions. Our data provide further evidence by which low dose metformin exerts protective effects against L-Doxo, a chemotherapeutic drug, under low glucose conditions. Metformin appears to act via AMPKα, Raptor, and SRF, and has significant cellular protective effects that may be useful in cancer and/or aging.

scholarly journals Low Glucose Enhances the Cytoprotective Effect of Metformin Against Doxorubicin Induced Cytotoxicity in Normal Cells

2020 ◽  
pp. 1-9
Author(s):  
Jeanne Y. Wei ◽  
Fathima S. Ameer ◽  
Xiaomin Zhang ◽  
Gohar Azhar ◽  
Yingni Che ◽  
...  
Keyword(s):  
Liposomal Doxorubicin ◽  
Mitochondrial Fission ◽  
Pegylated Liposomal Doxorubicin ◽  
C2c12 Cells ◽  
C2c12 Myoblast ◽  
Protective Effects ◽  
Gene Expressions ◽  
Normal Cells ◽  
Biochemical Alterations ◽  
Low Glucose

The anti-diabetic drug, metformin, has been reported to be beneficial for the cardiovascular system and may facilitate the extension of a healthier lifespan. Doxorubicin is a leading chemotherapeutic drug used to treat a variety of cancers, yet it can cause significant adverse effects with cardiac toxicity and longterm damage. To test the hypothesis that the hypoglycaemic agent, metformin, may protect normal cells during chemotherapy treatment with liposomal doxorubicin, C2C12 myoblast cells were used to study cellular bioenergetics, variations in gene expressions and biochemical alterations induced by metformin and pegylated liposomal doxorubicin (L-Doxo) under low glucose conditions (2.7 mM or 50 mg/dL). Using confocal microscopy, we noted that treatment of C2C12 cells with 30 µg/mL L-Doxo under low glucose conditions induced a number of cellular defects. L-Doxo treatment dysregulated the expression of mitochondrial fission and fusion genes, which may influence transformation of the network’s connectivity. L-Doxo significantly reduced mitochondrial oxygen consumption rate (OCR) and extracellular acidification rate (ECAR). However, pre-treatment of cells with 100 nM metformin provided protection against L-Doxo-induced damage and increased cell viability and ATP levels in cells even under low glucose conditions. In addition, metformin increased and restored the decreased OCR and ECAR. Our data provide a mechanism by which low dose metformin exerts protective effects against L-Doxo via involvement of AMPKα under low glucose conditions. Taken together, our results demonstrate that metformin protects normal cells from L-Doxo damage even under low glucose conditions.

scholarly journals Osteocalcin Induces Proliferation via Positive Activation of the PI3K/Akt, P38 MAPK Pathways and Promotes Differentiation Through Activation of the GPRC6A-ERK1/2 Pathway in C2C12 Myoblast Cells

2017 ◽  
Vol 43 (3) ◽  
pp. 1100-1112 ◽  
Author(s):  
Suifeng Liu ◽  
Feng Gao ◽  
Lei Wen ◽  
Min Ouyang ◽  
Yi Wang ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
P38 Mapk ◽  
C2c12 Cell ◽  
C2c12 Cells ◽  
Myoblast Differentiation ◽  
C2c12 Myoblast ◽  
C2c12 Myoblasts ◽  
Mapk Phosphorylation ◽  
Mapk Pathways ◽  
Myoblast Cells

Background/Aims: Sarcopenia is characterized by an age-related decline in skeletal muscle plus low muscle strength and/or physical performance. Despite the clinical significance of sarcopenia, the molecular pathways underlying sarcopenia remain elusive. The recent demonstration that undercarboxylated osteocalcin (ucOC) favours muscle function related to insulin sensitivity and glucose metabolism raises the question of whether this hormone may also regulate muscle mass. The present study explored the promotive effects of ucOC in proliferation and differentiation processes of C2C12 myoblasts as well as the possible signalling pathways involved. Methods: The effects of exogenous ucOC on C2C12 myoblasts proliferation were assessed using CCK8 and immunohistological staining assays. C2C12 cells were pretreated with PI3K/Akt or P38 MAPK inhibitors to investigate the possible involvement of the PI3K/Akt and P38 MAPK pathways in proliferation. The levels of Akt, phosphorylated-Akt (p-Akt), P38, and phosphorylated-P38 (p-P38) were measured by Western Blotting. The effects of ucOC on myoblast differentiation were quantified by morphological analysis. A silencing experiment was conducted in which the expression of GPRC6A in C2C12 myoblasts was modified. The expression of GPRC6A, myosin heavy chain (MyHC) and the related ERK1/2 signalling pathway in C2C12 myoblasts were monitored by qRT-PCR and Western Blotting. Results: We showed that treatment with exogenous ucOC stimulated the priming of C2C12 myoblasts proliferation. Inhibition of Akt phosphorylation by wortmannin or inhibition of P38 MAPK phosphorylation by SB203580 decreased C2C12 cell proliferation. Wortmannin also reduced P38 MAPK phosphorylation, whereas SB203580 did not affect Akt activation. Furthermore, ucOC promoted C2C12 myoblast differentiation. Inhibition of ERK1/2 phosphorylation with U0126 decreased C2C12 cell differentiation. Finally, GPRC6A expression was substantially increased after ucOC treatment of C2C12 cells. GPRC6A silencing inhibited Akt, P38 MAPK phosphorylation in C2C12 cells, and ERK1/2 phosphorylation in C2C12 myotubes; GPRC6A silencing also decreased cell proliferation, decreased cell differentiation, and downregulated MyHC expression. Conclusions: The present data suggest that ucOC induces myoblast proliferation via sequential activation of the PI3K/Akt and p38 MAPK pathways in C2C12 myoblast cells. Moreover, ucOC enhances myogenic differentiation via a mechanism involving GPRC6A-ERK1/2 signalling.

scholarly journals Ganoderma microsporum immunomodulatory protein, GMI, promotes C2C12 myoblast differentiation in vitro via upregulation of Tid1 and STAT3 acetylation

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244791
Author(s):  
Wan-Huai Teo ◽  
Jeng-Fan Lo ◽  
Yu-Ning Fan ◽  
Chih-Yang Huang ◽  
Tung-Fu Huang
Keyword(s):  
Myogenic Differentiation ◽  
Atp Synthesis ◽  
C2c12 Cells ◽  
Myoblast Differentiation ◽  
C2c12 Myoblast ◽  
Muscle Loss ◽  
C2c12 Myoblasts ◽  
Immunomodulatory Protein ◽  
Pre Treatment

Ageing and chronic diseases lead to muscle loss and impair the regeneration of skeletal muscle. Thus, it’s crucial to seek for effective intervention to improve the muscle regeneration. Tid1, a mitochondrial co-chaperone, is important to maintain mitochondrial membrane potential and ATP synthesis. Previously, we demonstrated that mice with skeletal muscular specific Tid1 deficiency displayed muscular dystrophy and postnatal lethality. Tid1 can interact with STAT3 protein, which also plays an important role during myogenesis. In this study, we used GMI, immunomodulatory protein of Ganoderma microsporum, as an inducer in C2C12 myoblast differentiation. We observed that GMI pretreatment promoted the myogenic differentiation of C2C12 myoblasts. We also showed that the upregulation of mitochondria protein Tid1 with the GMI pre-treatment promoted myogenic differentiation ability of C2C12 cells. Strikingly, we observed the concomitant elevation of STAT3 acetylation (Ac-STAT3) during C2C12 myogenesis. Our study suggests that GMI promotes the myogenic differentiation through the activation of Tid1 and Ac-STAT3.

scholarly journals Nogo-A is critical for pro-inflammatory gene regulation in myocytes and macrophages

2020 ◽  
Author(s):  
H M Arif Ullah ◽  
A. K. Elfadl ◽  
SunYoung Park ◽  
Yong Deuk Kim ◽  
Myung-Jin Chung ◽  
...  
Keyword(s):  
Inflammatory Process ◽  
Vital Role ◽  
C2c12 Cells ◽  
Inflammatory Factors ◽  
Mdx Mice ◽  
C2c12 Myoblast ◽  
Homologous Protein ◽  
Inflammatory Processes ◽  
Myoblast Cells ◽  
Factor C

Abstract Background: Nogo-A (Rtn 4A), a member of the reticulon 4 (Rtn4) protein family, is a neurite outgrowth inhibitor protein that is primarily expressed in the central nervous system (CNS). However, the role of Nogo-A in inflammatory mechanisms remains unclear. Therefore, in this study, we used Nogo-knockout (KO) mice to explore its potential role in the inflammatory process. Here, we investigated whether Nogo-A affects the inflammatory process through transcription factor C/EBP homologous protein (CHOP). Results: Our results demonstrated that Nogo-A, CHOP, and pro-inflammatory factors were activated in the following: notexin-induced muscle injury, in human Duchenne muscular dystrophy (DMD) patients, in dystrophin-deficient (mdx) mice, in differentiated C2C12 myoblast cells, and in lipopolysaccharide (LPS)-stimulated bone marrow-derived macrophages (BMDM). Moreover, we found that Nogo-KO BMDM exhibited lower migratory ability compared with wild type (WT) BMDM after LPS treatment. Conclusion: Our data demonstrated that the Nogo-A-CHOP signaling pathway regulated the inflammatory process in notexin-induced injured muscle, in mdx mice, in DMD patients, in differentiated C2C12 cells, and in LPS-stimulated BMDM. Taken together, these results suggest that Nogo-A plays a vital role in inflammatory processes, which resembles the pathological mechanisms observed in the CNS.

scholarly journals Low-level laser prevents doxorubicin-induced skeletal muscle atrophy by modulating AMPK/SIRT1/PCG-1α-mediated mitochondrial function, apoptosis and up-regulation of pro-inflammatory responses

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hsiu-Chung Ou ◽  
Pei-Ming Chu ◽  
Yu-Ting Huang ◽  
Hui-Ching Cheng ◽  
Wan-Ching Chou ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Muscle Atrophy ◽  
Muscle Wasting ◽  
Inflammatory Responses ◽  
C2c12 Cells ◽  
Skeletal Muscle Atrophy ◽  
C2c12 Myoblast ◽  
Protective Effects ◽  
Low Level ◽  
Beneficial Effects

Abstract Background Doxorubicin (Dox) is a widely used anthracycline drug to treat cancer, yet numerous adverse effects influencing different organs may offset the treatment outcome, which in turn affects the patient’s quality of life. Low-level lasers (LLLs) have resulted in several novel indications in addition to traditional orthopedic conditions, such as increased fatigue resistance and muscle strength. However, the mechanisms by which LLL irradiation exerts beneficial effects on muscle atrophy are still largely unknown. Results The present study aimed to test our hypothesis that LLL irradiation protects skeletal muscles against Dox-induced muscle wasting by using both animal and C2C12 myoblast cell models. We established SD rats treated with 4 consecutive Dox injections (12 mg/kg cumulative dose) and C2C12 myoblast cells incubated with 2 μM Dox to explore the protective effects of LLL irradiation. We found that LLL irradiation markedly alleviated Dox-induced muscle wasting in rats. Additionally, LLL irradiation inhibited Dox-induced mitochondrial dysfunction, apoptosis, and oxidative stress via the activation of AMPK and upregulation of SIRT1 with its downstream signaling PGC-1α. These aforementioned beneficial effects of LLL irradiation were reversed by knockdown AMPK, SIRT1, and PGC-1α in C2C12 cells transfected with siRNA and were negated by cotreatment with mitochondrial antioxidant and P38MAPK inhibitor. Therefore, AMPK/SIRT1/PGC-1α pathway activation may represent a new mechanism by which LLL irradiation exerts protection against Dox myotoxicity through preservation of mitochondrial homeostasis and alleviation of oxidative stress and apoptosis. Conclusion Our findings may provide a novel adjuvant intervention that can potentially benefit cancer patients from Dox-induced muscle wasting.

scholarly journals Platelet-poor plasma of athletes is a potent inducer of myogenic differentiation of C2C12 myoblasts

2020 ◽  
Vol 74 (1) ◽  
pp. 18-33
Author(s):  
Irina Maslovaric ◽  
Vesna Ilic ◽  
Ana Stancic ◽  
Juan Santibanez ◽  
Drenka Trivanovic ◽  
...  
Keyword(s):  
Myogenic Differentiation ◽  
Platelet Rich Plasma ◽  
C2c12 Cell ◽  
C2c12 Cells ◽  
Football Players ◽  
C2c12 Myoblast ◽  
Potent Inducer ◽  
Gelatinase Activity ◽  
Platelet Poor Plasma ◽  
Myoblast Cells

Introduction. Blood products, i.e. platelet rich plasma (PRP), leukocyte-poor plasma (PRP) and platelet poor plasma (PPP), have previously been used to improve muscle regeneration. In this study, six months? frozen-stored PPP of individuals who practiced different types of physical exercise was analysed; it could steer mouse C2C12 myoblast cells towards proliferation, migration and myogenic differentiation, and it could affect the morphology/shape of myotubes. Materials and Methods. PPP of male Olympic weightlifters, football players and professional folk dancers, aged 15-19, was collected 12 h post-training and stored for 6 months at -20?C. C2C12 cell proliferation was assessed by MTT test, motility by scratch assay, myogenic differentiation by myotube formation and gelatinase activity by gel-zymography. Results and Conclusions. PPP induced proliferation and migration of C2C12 cells. Proliferative capacity was as follows: weightlifters > dancers > football players; mean migratory capacity was: weightlifters = dancers > football players. PPP induced formation of myotubes; significant inter-individual variations were detected: PPP from weightlifters induced formation of round myotubes, and PPP from football players and dancers induced formation of elongated myotubes. The mean myotube area was as follows: football players > dancers > weightlifters. PPP gelatinolytic activity was observed; it was negatively correlated with C2C12 myoblast proliferation. These results provide general but distinct evidence that PPP of individuals practicing certain types of exercise can specifically modify myoblast morphology/function. This is significant for explaining physiological responses and adaptations to exercise. In conclusion, long-term, frozen-stored PPP preserves its potential to modify myoblast morphology and function.

scholarly journals 2-D08 treatment regulates C2C12 myoblast proliferation and differentiation via the Erk1/2 and proteasome signaling pathways

2021 ◽  
Author(s):  
Hyunju Liu ◽  
Su-Mi Lee ◽  
Hosouk Joung
Keyword(s):  
Myogenic Differentiation ◽  
C2c12 Cell ◽  
C2c12 Cells ◽  
Covalent Attachment ◽  
Myoblast Differentiation ◽  
C2c12 Myoblast ◽  
Long Term Effects ◽  
Proliferation And Differentiation ◽  
Myoblast Proliferation ◽  
Myoblast Cells

AbstractSUMOylation is one of the post-translational modifications that involves the covalent attachment of the small ubiquitin-like modifier (SUMO) to the substrate. SUMOylation regulates multiple biological processes, including myoblast proliferation, differentiation, and apoptosis. 2-D08 is a synthetically available flavone, which acts as a potent cell-permeable SUMOylation inhibitor. Its mechanism of action involves preventing the transfer of SUMO from the E2 thioester to the substrate without influencing SUMO-activating enzyme E1 (SAE-1/2) or E2 Ubc9-SUMO thioester formation. However, both the effects and mechanisms of 2-D08 on C2C12 myoblast cells remain unclear. In the present study, we found that treatment with 2-D08 inhibits C2C12 cell proliferation and differentiation. We confirmed that 2-D08 significantly hampers the viability of C2C12 cells. Additionally, it inhibited myogenic differentiation, decreasing myosin heavy chain (MHC), MyoD, and myogenin expression. Furthermore, we confirmed that 2-D08-mediated anti-myogenic effects impair myoblast differentiation and myotube formation, reducing the number of MHC-positive C2C12 cells. In addition, we found that 2-D08 induces the activation of ErK1/2 and the degradation of MyoD and myogenin in C2C12 cells. Taken together, these results indicated that 2-D08 treatment results in the deregulated proliferation and differentiation of myoblasts. However, further research is needed to investigate the long-term effects of 2-D08 on skeletal muscles.

Transcriptional Regulation of the Murine Urokinase-type Plasminogen Activator Gene in Skeletal Myoblasts

1999 ◽  
Vol 81 (05) ◽  
pp. 767-774 ◽  
Author(s):  
Francesc Miralles ◽  
Inés Ibáñez-Tallon ◽  
Maribel Parra ◽  
Massimo Crippa ◽  
Francesco Blasi ◽  
...  
Keyword(s):  
Plasminogen Activator ◽  
C2c12 Cells ◽  
Regulatory Function ◽  
C2c12 Myoblast ◽  
Mobility Shift ◽  
Nuclear Extracts ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator ◽  
Myoblast Cells

SummaryWe have previously shown that urokinase-type plasminogen activator (uPA) is highly expressed in murine C2C12 myoblasts and that antibodies against uPA are able to block both myoblast fusion and differentiation. Here we show the characterization of cis-acting elements in the mouse uPA promoter in vitro which are involved in uPA gene expression in C2C12 myoblast cells. DNase I hypersensitive (HS) site analysis revealed the presence of three HS sites in myoblasts. Deletion analysis of stably transfected uPA-promoter constructs revealed that at least two of the three HS sites accounted for the high transcriptional expression in C2C12 cells. One was located at -2.4 kb and corresponded to a known PEA3/AP1A element and the other one was located at -4.9 kb and contained a CArG box and a CRE element. So far, no regulatory function had been assigned to this CRE/CArG element. Both HS sites alone were able to activate transcription of a heterologous promoter and showed a cooperative effect when placed together. Electrophoretic mobility-shift assays using myoblast nuclear extracts and specific antibodies demonstrated that cJun, JunD and ATF2 bound to the PEA3/AP1A element, whereas the CRE/CArG element bound SRF. Altogether, these results suggest that high uPA expression in myoblasts is dependent on the cooperation of two regulatory sites in the uPA promoter.

scholarly journals Curcumin Ameliorated Oxidative Stress and Inflammation-Related Muscle Disorders in C2C12 Myoblast Cells

Antioxidants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 476
Author(s):  
Da-Yeon Lee ◽  
Yoon-Seok Chun ◽  
Jong-Kyu Kim ◽  
Jeong-Ok Lee ◽  
Young-Joon Lee ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Radical Scavenging ◽  
C2c12 Cells ◽  
C2c12 Myoblast ◽  
Related Factor ◽  
Dependent Manner ◽  
Quinone Oxidoreductase ◽  
Muscle Disorders ◽  
Myoblast Cells ◽  
Dose Dependent

The purpose of the current study was to investigate antioxidant and anti-inflammatory effects of spray dry powder containing 40% curcumin (CM-SD) in C2C12 myoblast cells. CM-SD increased DPPH radical scavenging activity in a dose-dependent manner, and up to 30 μg/mL of CM-SD did not express cytotoxicity in C2C12 cells. Exposure to hydrogen peroxide (H2O2) drastically decreased the viability of C2C12 cells, but pre-treatment of CM-SD significantly increased the cell viability (p < 0.01). CM-SD significantly transactivated the nuclear factor erythroid-2-related factor 2 (Nrf2)-dependent luciferase activity in a dose-dependent manner and enhanced the levels of heme oxygenase (HO)-1, glutamate cysteine ligase catalytic subunit (GCLC), and NAD(P)H-dependent quinone oxidoreductase (NQO)-1. CM-SD also significantly reduced reactive oxygen species (ROS) production and lipid peroxidation and restored glutathione (GSH) depletion in H2O2-treated C2C12 cells. Moreover, CM-SD significantly reduced lipopolysaccharides (LPS)-mediated interleukin (IL)-6 production in the conditioned medium. Results from the current study suggest that CM-SD could be a useful candidate against oxidative stress and inflammation-related muscle disorders.

scholarly journals A Study of C2C12 Myoblast Bioenergetics in Response to the CCG-1423 Rho A Inhibitor

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 689-689
Author(s):  
Bachkhoa Nguyen ◽  
Fathima Ameer ◽  
Jasmine Crane ◽  
Gohar Azhar ◽  
Xiaomin Zhang ◽  
...  
Keyword(s):  
Gene Expression ◽  
Oxygen Consumption ◽  
Mitochondrial Function ◽  
Consumption Rate ◽  
C2c12 Cells ◽  
C2c12 Myoblast ◽  
Dependent Manner ◽  
Mitochondrial Oxygen Consumption ◽  
Myoblast Cells ◽  
Dose Dependent

Abstract CCG-1423 is a Rho A pathway inhibitor which has been reported to inhibit Rho/SRF-mediated transcriptional regulation. SRF and SRF cofactors, which include ternary complex factors (TCFs) and myocardin-related transcription factor (MRTF), regulate various cellular functions. The Rho/SRF signaling pathway also regulates the sirtuin 2 (SIRT2) gene that contains a classic serum response element (SRE) sequence. Current research on CCG-1423 focuses on gene expression levels of SRF in response to CCG-1423 and how SRF levels affect the cells; the studies are focused on cell morphology, migration, viability/reproduction, and overall function. The pathways of this inhibitor have yet to be fully elucidated, but several have been suggested with good evidence. Our goal is to study the effect of CCG-1423 on mitochondrial function and gene expression of cells. In this work C2C12 myoblast cells have been used as an in-vitro model to study cellular bioenergetics and variations in gene expressions induced by CCG-1423. The effect of CCG-1423 on mitochondrial function was determined by measuring the mitochondrial oxygen consumption rate and glycolysis rate after treating C2C12 cells with varying concentrations of CCG-1423 overnight. In C2C12 myoblast cells, CCG-1423 treatment significantly reduced mitochondrial oxygen consumption rate (OCR) in a dose-dependent manner. However, treatment of C2C12 cells with CCG-1423 overnight increased the extracellular acidification rate (ECAR) in a dose-dependent manner. By indicating that CCG-1423 represses mitochondrial respiration via the Rho-SRF signaling pathway, the results of this study may enable a better understanding of the bioenergetics of the cell in the aging body.

Sign in / Sign up

Export Citation Format

Share Document