• Journal of Life Science
• /
• v.28 no.4
• /
• pp.435-443
• /
• 2018

AMP-activated protein kinase (AMPK) functions as a metabolic master through regulating and restoring cellular energy balance. In skeletal muscle, AMPK increases myofibril protein degradation through the expression of muscle-specific ubiquitin ligases. Mori Folium, the leaf of Morus alba, is a traditional medicinal herb with various pharmacological functions; however, the effects associated with muscle atrophy have not been fully identified. In this study, we confirmed the effects of AMPK activation by examining the effects of 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR), an activator of AMPK, on the induction of atrophy and expression of atrophy-related genes in C2C12 myotubes. We also investigated the effects of the ethanol extract of Mori Folium (EEMF) on the recovery of AICAR-induced muscle atrophy in C2C12 myotubes. It was found that exposure to AICAR resulted in the stimulation of Forkhead box O3a (FOXO3a); an up-regulation of muscle-specific ubiquitin ligases such as Muscle Atrophy F-box (MAFbx)/atrogin-1 and muscle RING finger-1 (MuRF1), and a down-regulation of muscle-specific transcription factors, such as MyoD and myogenin; with the activation of AMPK. In addition, AICAR without cytotoxicity indicated a decrease in diameter of C2C12 myotubes. However, treatment with EEMF significantly suppressed AICAR-induced muscle atrophy of C2C12 myotubes in a dose-dependent manner as confirmed by a decrease in myotube diameter, which is associated with a reversed stimulation of FOXO3a by the inhibition of AMPK activation. These results indicate that the activation of AMPK by AICAR induces muscle atrophy, and EEMF has preeminent effects on the inhibition of AICAR-induced muscle atrophy through the AMPK signaling pathway.

• IMMUNE NETWORK
• /
• v.16 no.4
• /
• pp.242-248
• /
• 2016

Thymic atrophy is a complication that results from exposure to many environmental stressors, disease treatments, and microbial challenges. Such acute stress-associated thymic loss can have a dramatic impact on the host's ability to replenish the necessary naïve T cell output to reconstitute the peripheral T cell numbers and repertoire to respond to new antigenic challenges. We have previously reported that treatment with the orexigenic hormone ghrelin results in an increase in the number and proliferation of thymocytes after dexamethasone challenge, suggesting a role for ghrelin in restraint stress-induced thymic involution and cell apoptosis and its potential use as a thymostimulatory agent. In an effort to understand how ghrelin suppresses thymic T cell apoptosis, we have examined the various signaling pathways induced by receptor-specific ghrelin stimulation using a restraint stress mouse model. In this model, stress-induced apoptosis in thymocytes was effectively blocked by ghrelin. Western blot analysis demonstrated that ghrelin prevents the cleavage of pro-apoptotic proteins such as Bim, Caspase-3, and PARP. In addition, ghrelin stimulation activates the Akt and Mitogen-activated protein kinases (MAPK) signaling pathways in a time/dose-dependent manner. Moreover, we also revealed the involvement of the FoxO3a pathway in the phosphorylation of Akt and ERK1/2. Together, these findings suggest that ghrelin inhibits apoptosis by modulating the stress-induced apoptotic signal pathway in the restraint-induced thymic apoptosis.

• Herbal Formula Science
• /
• v.29 no.1
• /
• pp.45-55
• /
• 2021

Objectives : This study was conducted to evaluate the anti-atrophic effect of polycan in dexamethasone-induced skeletal muscle atrophy in vitro model. Methods : C2C12 myoblast were differentiated into myotube by 2% horese serum medium for 6 days, and then treated polycan extract at different concentrations for 24h. The effect of dexamethasone on the induction of muscle atrophy and expression of atrophy-related genes in differentiated C2C12 myotubes using a GSH, ROS, real-time PCR, western blots analysis. Results : The results showed that Treatment with polycan (100 and 200 ㎍/㎖) noncytotoxic levels on both myoblast and myotube. Polycan decreased the ROS level overproduced with dexamethasone and improved the depletion of GSH level. Dexamethasone showed a decrease in myotube diameter, which was associated with up-regulation muscle-specific ubiquitin ligases markers, such as atrogin-1, FoxO3, myostatin and muscle RING finger-1 (MuRF1), and down-regulation of myogenin, MEF2, Myogenic regulatory factor 5, 6 and MyoD. The results showed that polycan treatment significantly dose-dependently inhibited it. Furthermore, decreased expressions of PI3K/Akt signal pathway by dexamethasone were reversed by treatment with polycan. Conclusions : Thus, polycan suppresses dexamethasone induced muscle atrophy in C2C12 myotube in vitro model through activation of PI3K/Akt pathway and protective effect of improve skeletal muscle function.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.38 no.1
• /
• pp.22-26
• /
• 2024

The purpose of this study was to identify the applicability, main compounds, and target genes of Cnidii Fructus (CF) in the treatment of gastritis using network pharmacology. The compounds in CF were searched in Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and a database of medicinal materials and chemical compounds in Northeast Asian traditional medicine (TM-MC). The target gene information of the compounds was collected from pubchem and cross-compared with the gastritis-related target gene information collected from Genecard to derive the target genes. Gene ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed on the derived target genes. Afterwards, network analysis between compounds and disease target genes was performed using cytoscape. We identified 121 active compounds and 139 target genes associated with gastritis. Pathways derived from the GO biological process and KEGG pathway DB primarily focus on target genes related to inflammation (IL-6, IL-8, TNF production, NF-κB transcription factor activity, and NF-κB signaling pathway) and cell death (PI3K-Akt, FoxO). Major targets for CF treatment of gastritis include TP53, TNF, BCL2, EGFR, NFKB1, ABCB1, PPARG, PTGS2, IL6, IL1B, and SOD1, along with major compounds such as coumarin, osthol, hexadecanoic acid, oleic acid, linoleic acid, and stigmasterol. This study provided CF's applicability for gastritis, related compounds, and target information. Evaluating CF's effectiveness in a preclinical gastritis model suggests its potential use in clinical practice for digestive system diseases.

• IMMUNE NETWORK
• /
• v.20 no.6
• /
• pp.50.1-50.11
• /
• 2020

Osteoporosis is prevalent in elderly women and it may cause dental implant failure. In particular, estrogen deficiency in postmenopausal women leads to higher rates of osteoporosis prevalence. Immune cell-mediated effects involving the development of osteoporosis have been studied previously; however, the role of IL-10-producing regulatory B (B10) cells in osteoporosis is largely unclear. Here, we examined the role of B10 cells in osteoporosis. C57BL/6 mice were subjected to ovariectomy (OVX). Fifteen weeks after OVX surgery, the first molar of the right maxillary was extracted, and twenty-four weeks after OVX surgery, serous progression of osteoporosis was observed in the alveolar bone. Moreover, the proportion of CD19⁺CD5⁺CD1d^high regulatory B cells, B10, and CD4⁺CD25⁺FoxP3⁺ regulatory T cells from the spleen of OVX mice decreased during the progression of osteoporosis, compared to controls. In contrast to regulatory cells, IL-17-producing Th (Th17) cell levels were increased in OVX mice. Adoptive transfer of B10 cells to OVX mice led to a decrease in Th17 cell abundance and inhibited the development of osteoporosis in the alveolar bone from OVX mice. Thus, our results suggest that B10 cells may help suppress osteoporosis development.

• Animal Bioscience
• /
• v.37 no.6
• /
• pp.982-992
• /
• 2024

Objective: Jining Grey goat is a local Chinese goat breed that is well known for its high fertility and excellent meat quality but shows low meat production performance. Numerous studies have focused on revealing the genetic mechanism of its high fertility, but its highlighting meat quality and muscle growth mechanism still need to be studied. Methods: In this research, an integrative analysis of the genomics and transcriptomics of Jining Grey goats compared with Boer goats was performed to identify candidate genes and pathways related to the mechanisms of meat quality and muscle development. Results: Our results overlap among five genes (ABHD2, FN1, PGM2L1, PRKAG3, RAVER2) and detected a set of candidate genes associated with fatty acid metabolism (PRKAG3, HADHB, FASN, ACADM), amino acid metabolism (KMT2C, PLOD3, NSD2, SETDB1, STT3B, MAN1A2, BCKDHB, NAT8L, P4HA3) and muscle development (MSTN, PPARGC1A, ANKRD2). Several pathways have also been detected, such as the FoxO signaling pathway and Apelin signaling pathway that play roles in lipid metabolism, lysine degradation, N-glycan biosynthesis, valine, leucine and isoleucine degradation that involving with amino acid metabolism. Conclusion: The comparative genomic and transcriptomic analysis of Jining Grey goat and Boer goat revealed the mechanisms underlying the meat quality and meat productive performance of goats. These results provide valuable information for future breeding of goats.

• Journal of Life Science
• /
• v.25 no.10
• /
• pp.1081-1090
• /
• 2015

Diabetes has been one of major health risks in industrialized countries. Allium hookeri is a wild herb distributed in India and Myanmar. The root of the plant has been used as food and medicine in Southeast Asia. We investigated Allium hookeri extract improves type 2 diabetes mellitus in C57BL/KSJ db/db obese mouse. C57BL/KSJ db/db obese mouse arise out of Type 2 diabetes and we treated Allium hookeri methanol extract 400 mg/kg (AH 400), 800 mg/kg (AH 800), positive control group (thiazolidinedine;TZDs) were administered orally for 8weeks. AH treated group normalized lipid enzyme system (triglyceride, total cholesterol, HDL-cholesterol and LDL-cholesterol) and serum glucose, HbA1c and plasma insulin level. AH treated group recovered β-cell damage by hyperglycemia and fatty liver disease. AH treated group significantly up regulated expression of Peroxisome proliferator-activated receptor gamma (PPAR-γ), pyruvate dehydrogenase kinase4 (PDK4), Sterol regulatory element-binding protein 1c (SREBP 1) and fork head box O1 (FOX 01) proteins in C57BL/KSJ db/db obese mouse liver. And we found that AH treated group decreased hepatic malondialdehyde formation in C57BL/KSJ db/db obese mouse liver. These results indicate that Allium hookeri methanol extract might be a potential anti-diabetic agent and could be useful in the treatment of type 2 diabetes mellitus.

• Journal of Ginseng Research
• /
• v.47 no.6
• /
• pp.726-734
• /
• 2023

Background: Skeletal muscles play a key role in physical activity and energy metabolism. The loss of skeletal muscle mass can cause problems related to metabolism and physical activity. Studies are being conducted to prevent such diseases by increasing the mass and regeneration capacity of muscles. Ginsenoside Rg5 has been reported to exhibit a broad range of pharmacological activities. However, studies on the effects of Rg5 on muscle differentiation and growth are scarce. Methods: To investigate the effects of Rg5 on myogenesis, C2C12 myoblasts were induced to differentiate with Rg5, followed by immunoblotting, immunostaining, and qRT-PCR for myogenic markers and promyogenic signaling (p38MAPK). Immunoprecipitation confirmed that Rg5 increased the interaction between MyoD and E2A via p38MAPK. To investigate the effects of Rg5 on prevention of muscle mass loss, C2C12 myotubes were treated with dexamethasone to induce muscle atrophy. Immunoblotting, immunostaining, and qRT-PCR were performed for myogenic markers, Akt/mTOR signaling for protein synthesis, and atrophy-related genes (Atrogin-1 and MuRF1). Results: Rg5 promoted C2C12 myoblast differentiation through phosphorylation of p38MAPK and MyoD/E2A heterodimerization. Furthermore, Rg5 stimulated C2C12 myotube hypertrophy via phosphorylation of Akt/mTOR. Phosphorylation of Akt induces FoxO3a phosphorylation, which reduces the expression of Atrogin-1 and MuRF1. Conclusion: This study provides an understanding of how Rg5 promotes myogenesis and hypertrophy and prevents dexamethasone-induced muscle atrophy. The study is the first, to the best of our knowledge, to show that Rg5 promotes muscle regeneration and to suggest that Rg5 can be used for therapeutic intervention of muscle weakness and atrophy, including cancer cachexia.

• Animal Bioscience
• /
• v.35 no.9
• /
• pp.1327-1339
• /
• 2022

Objective: Fat deposition in poultry is an important factor in production performance and meat quality research. miRNAs also play important roles in regulating adipocyte differentiation process. This study was to investigate the expression patterns of miRNAs in duck adipocytes after differentiation and explore the role of miR-214 in regulating carnitine palmitoyltransferases 2 (CPT2) gene expression during duck adipocyte differentiation. Methods: Successful systems for the isolation, culture, and induction of duck primary fat cells was developed in the experiment. Using Illumina next-generation sequencing, the miRNAs libraries of duck adipocytes were established. miRanda was used to predict differentially expressed (DE) miRNAs and their target genes. The expression patterns of miR-214 and CPT2 during the differentiation were verified by quantitative real-time polymerase chain reaction and western blot. Luciferase reporter assays were used to explore the specific regions of CPT2 targeted by miR-214. We used a miR-214 over-expression strategy in vitro to further investigate its effect on differentiation process and CPT2 gene transcription. Results: There were 481 miRNAs identified in duck adipocytes, included 57 DE miRNA candidates. And the 1,046 targets genes of DE miRNAs were mainly involved in p53 signaling, FoxO signaling, and fatty acid metabolism pathways. miR-214 and CPT2 showed contrasting expression patterns before and after differentiation, and they were selected for further research. The expression of miR-214 was decreased during the first 3 days of duck adipocytes differentiation, and then increased, while the expression of CPT2 increased both in the transcriptional and protein level. The luciferase assay suggested that miR-214 targets the 3'untranslated region of CPT2. Overexpression of miR-214 not only promoted the formation of lipid droplets but also decreased the protein abundance of CPT2. Conclusion: Current study reports the expression profile of miRNAs in duck adipocytes differentiated for 4 days. And miR-214 has been proved to have the regulator potential for fat deposition in duck.