Ginsenoside Rg5 Improves Insulin Resistance and Mitochondrial Biogenesis of Liver via Regulation of the Sirt1/PGC-1α Signaling Pathway in db/db Mice

Author(s):  
Yanyan Zhu ◽  
Haixia Yang ◽  
Jianjun Deng ◽  
Daidi Fan
2020 ◽  
Vol 17 ◽  
Author(s):  
Qian Lu ◽  
Hai-Zhu Xing ◽  
Nian-Yun Yang

Background: CCl4 acute liver injury (ALI) is a classical model for experimental research. However, there are few reports involved in the fundamental research of CCl4-induced ALI Ligustri Lucidi Fructus (LLF) are and its prescription have been used to treat hepatitis illness clinically. LLF and its active ingredients displayed anti-hepatitis effects, but the mechanism of function has not been fully clarified Objective: To investigate the proteomic analysis of CCl4-induced ALI, and examine the effects of active total glycosides (TG) from LLF on ALI of mice4, including histopathological survey and proteomic changes of liver tissues, and delineate the possible underlying mechanism. Methods: CCl4 was used to produce ALI mice model. The model mice were intragastrically administrated with TG and the liver his-topathological changes of mice were examined. At the end of test, mice liver samples were collected, after protein denaturation, re-duction, desalination and enzymatic hydrolysis, identification was carried out by nano LC-ESI-OrbiTrap MS/MS technology. The data was processed by Maxquant software. The differentially-expressed proteins were screened and identified, and their biological information was also analyzed based on GO and KEGG analysis. Key protein expression was validated by Western blot analysis Results: A total of 705 differentially-expressed proteins were identified during the normal, model and administration group. 9 signifi-cant differential proteins were focused based on analysis. Liver protein expression changes of CCl4-induced ALI mice were mainly involved in several important signal channels, namely FoxO signaling pathway, autophagy-animal, insulin signaling pathway. TG has anti-liver damnification effect in ALI mice, the mechanism of which is related to FoxO1 and autophagy pathways Conclusion: CCl4 inhibited expression of insulin-Like growth factor 1 (Igf1) and 3-phosphoinositide-dependent protein kinase 1 (Pdpk1) in liver cells and induced insulin resistance, thus interfered with mitochondrial autophagy and regeneration of liver cells and the metabolism of glucose and lipid, and caused hepatic necrosis in mice. TG resisted liver injury in mice. TG adjusted the expression level of key proteins Igf1 and Pdpk1 after liver injury and improved insulin resistance, thus promoted autophagy and resisted the liver damage


Author(s):  
Chih-Chieh Chen ◽  
Chong-Kuei Lii ◽  
Chia-Wen Lo ◽  
Yi-Hsueh Lin ◽  
Ya-Chen Yang ◽  
...  

14-Deoxy-11,12-didehydroandrographolide (deAND), a bioactive component of Andrographis paniculata, has antidiabetic activity. AMP-activated protein kinase (AMPK) regulates glucose transport and ameliorates insulin resistance. The aim of the present study was to investigate whether activation of AMPK is involved in the mechanism by which deAND ameliorates insulin resistance in muscles. deAND amounts up to 40 [Formula: see text]M dose-dependently activated phosphorylation of AMPK[Formula: see text] and TBC1D1 in C2C12 myotubes. In addition, deAND significantly activated phosphorylation of LKB1 at 6 h after treatment, and this activation was maintained up to 48 h. deAND increased glucose uptake at 18 h after treatment, and this increase was time dependent up to 72 h. Compound C, an inhibitor of AMPK, suppressed deAND-induced phosphorylation of AMPK[Formula: see text] and TBC1D1 and reversed the effect on glucose uptake. In addition, the expression of GLUT4 mRNA and protein in C2C12 myotubes was up-regulated by deAND in a time-dependent manner. Promotion of GLUT4 gene transcription was verified by a pGL3-GLUT4 (837 bp) reporter assay. deAND also increased the nuclear translocation of MEF-2A and PPAR[Formula: see text]. After 16 weeks of feeding, the high-fat diet (HFD) inhibited phosphorylation of AMPK[Formula: see text] and TBC1D1 in skeletal muscle of obese C57BL/6JNarl mice, and deactivation of AMPK[Formula: see text] and TBC1D1 by the HFD was abolished by deAND supplementation. Supplementation with deAND significantly promoted membrane translocation of GLUT4 compared with the HFD group. Supplementation also significantly increased GLUT4 mRNA and protein expression in skeletal muscle compared with the HFD group. The hypoglycemic effects of deAND are likely associated with activation of the LKB1/AMPK[Formula: see text]/TBC1D1/GLUT4 signaling pathway and stimulation of MEF-2A- and PPAR[Formula: see text]-dependent GLUT4 gene expression, which account for the glucose uptake into skeletal muscle and lower blood glucose levels.


2019 ◽  
Vol 316 (2) ◽  
pp. C223-C234 ◽  
Author(s):  
Yong Wang ◽  
Yun-Sheng Cheng ◽  
Xiao-Qiang Yin ◽  
Gang Yu ◽  
Ben-Li Jia

Insulin resistance (IR) continues to pose a major threat to public health due to its role in the pathogenesis of metabolic syndrome and its ever-increasing prevalence on a global scale. The aim of the current study was to investigate the efficacy of Anxa2 in obesity-induced IR through the mediation of the NF-κB signaling pathway. Microarray analysis was performed to screen differentially expressed genes associated with obesity. To verify whether Anxa2 was differentially expressed in IR triggered by obesity, IR mouse models were established in connection with a high-fat diet (HFD). In the mouse IR model, the role of differentially expressed Anxa2 in glycometabolism and IR was subsequently detected. To investigate the effect of Anxa2 on IR and its correlation with inflammation, a palmitic acid (PA)-induced IR cell model was established, with the relationship between Anxa2 and the NF-κB signaling pathway investigated accordingly. Anxa2 was determined to be highly expressed in IR. Silencing Anxa2 was shown to inhibit IR triggered by obesity. When Anxa2 was knocked down, elevated expression of phosphorylated insulin receptor substrate 1 (IRS1), IRS1 and peroxisome proliferator-activated receptor coactivator-1a, and glucose tolerance and insulin sensitivity along with 2-deoxy-d-glucose uptake was detected, whereas decreased expression of suppressor of cytokine signaling 3, IL-6, IL-1β, TNF-α, and p50 was observed. Taken together, the current study ultimately demonstrated that Anxa2 may be a novel drug strategy for IR disruption, indicating that Anxa2 gene silencing is capable of alleviating PA or HFD-induced IR and inflammation through its negative regulatory role in the process of p50 nuclear translocation of the NF-κB signaling pathway.


Nutrients ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3771
Author(s):  
Laurent L’homme ◽  
Benan Pelin Sermikli ◽  
Bart Staels ◽  
Jacques Piette ◽  
Sylvie Legrand-Poels ◽  
...  

Growth differentiation factor-15 (GDF-15) and its receptor GFRAL are both involved in the development of obesity and insulin resistance. Plasmatic GDF-15 level increases with obesity and is positively associated with disease progression. Despite macrophages have been recently suggested as a key source of GDF-15 in obesity, little is known about the regulation of GDF-15 in these cells. In the present work, we sought for potential pathophysiological activators of GDF15 expression in human macrophages and identified saturated fatty acids (SFAs) as strong inducers of GDF15 expression and secretion. SFAs increase GDF15 expression through the induction of an ER stress and the activation of the PERK/eIF2/CHOP signaling pathway in both PMA-differentiated THP-1 cells and in primary monocyte-derived macrophages. The transcription factor CHOP directly binds to the GDF15 promoter region and regulates GDF15 expression. Unlike SFAs, unsaturated fatty acids do not promote GDF15 expression and rather inhibit both SFA-induced GDF15 expression and ER stress. These results suggest that free fatty acids may be involved in the control of GDF-15 and provide new molecular insights about how diet and lipid metabolism may regulate the development of obesity and T2D.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Ritika Singh ◽  
Lucy Mohapatra ◽  
Alok Shiomurthi Tripathi

Abstract Background Diabetes mellitus is a lingering hyperglycemic ailment resulting in several life-threatening difficulties. Enduring hyperglycemia often persuades the buildup of reactive oxygen species that are the significant pathological makers of diabetic complications. The mitochondrial dysfunction, with mitochondrial damage and too much production of reactive oxygen species, have been proposed to be convoluted in the progress of insulin resistance. Numerous studies advocate that agents that enhance the mitochondrial number and/or decrease their dysfunction, could be greatly helpful in management of diabetes and its complications. Main body Mitochondrial biogenesis is an extremely delimited procedure arbitrated by numerous transcription influences, in which mitochondrial fusion and fission happen in synchronization in a standard vigorous cell. But this synchronization is greatly disturbed in diabetic condition designated by modification in the working of several important transcription factors regulating the expressions of different genes. Numerous preclinical and clinical investigations have suggested that, the compromised functions of mitochondria play a significant protagonist in development of pancreatic β-cell dysfunction, skeletal muscle insulin resistance and several diabetic complications. However, there are several phytoconstituents performing through numerous alleyways, either unswervingly by motivating biogenesis or indirectly by constraining or averting dysfunction and producing a beneficial effect on overall function of the mitochondria. Conclusion This review describes standard mitochondrial physiology and anomalous modifications that transpire in answer to persistent hyperglycemia in diabetes condition. It also discusses about the different phytoconstituents that can affect the biogenesis pathways of mitochondria and thus can be used in the treatment and prevention of diabetes.


2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Bo Ren ◽  
Luanfeng Wang ◽  
Zhigang Liu ◽  
Xuebo Liu

Abstract Objectives Moderate dietary methionine restriction (MR) extends life span in various animal models and delays the onset of aging-associated pathologies. However, the neuroprotective effects and underlying mechanism of MR on age and age-related diseases still remain to be investigated. Notably, fibroblast growth factor-21 (FGF21), a MR responding hormone mostly generated from liver, plays a critical role in neuronal mitochondrial function. Here, we aimed to reveal the neuroprotective effects of MR and the mediating role of FGF21 in aging mice model. Methods Male C57BL/6 mice (2-, 12-, and 15- month-old) were treated with control methionine diet (0.86% methionine) and methionine restriction diet (0.17% methionine) for 3 months. Adeno-associated virus was employed to build FGF21 knockdown mice model. Behavioral tests, synapse ultrastructure detection, and amino acid metabolomics were performed to evaluate cognitive function, neuron damage and signaling pathway activation. Results In behavioral tests, we found that MR significantly improved aging-induced decreased in spatial memory and cognitive function. Meanwhile, MR ameliorated neuronal damage and synapses structure damages in aging mice hippocampus. Moreover, MR significantly improved the mRNA expression of mitochondrial biogenesis and dynamics related genes such as COX2/fis1/pink1/binp1/drp1 in aging mice brain. MR also altered plasma amino acid metabolic phenotype-related glutathione synthesis, energy metabolism, and nervous system function. Furthermore, we found that MR could significant increase FGF21 level in both liver and serum of aging mice. Knockdown of FGF21 dramatically diminished the benefits of MR on cognitive impairments. Conclusions These results showed that MR mitigated aging-induced memory impairment and synapses structure damages via activating FGF21 signaling pathway. The study suggest that this dietary restriction might be plausible therapeutic intervention for aging and other neurodegenerative diseases such AD and PD. Funding Sources This work was financially supported by the National Key Research and Development Program of China, National Natural Science Foundation of China. Supporting Tables, Images and/or Graphs


Sign in / Sign up

Export Citation Format

Share Document