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Yan Z, Ji F, Yan R, Jiao J, Wang W, Zhang M, Li F, Zhao Y, Chang Z, Yan S, Li J. Reyanning mixture inhibits M1 macrophage polarization through the glycogen synthesis pathway to improve lipopolysaccharide-induced acute lung injury. J Ethnopharmacol 2024; 328:118005. [PMID: 38508433 DOI: 10.1016/j.jep.2024.118005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 02/23/2024] [Accepted: 03/01/2024] [Indexed: 03/22/2024]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Reyanning (RYN) mixture is a traditional Chinese medicine composed of Taraxacum, Polygonum cuspidatum, Scutellariae Barbatae and Patrinia villosa and is used for the treatment of acute respiratory system diseases with significant clinical efficacy. AIM OF THE STUDY Acute lung injury (ALI) is a common clinical disease characterized by acute respiratory failure. This study was conducted to evaluate the therapeutic effects of RYN on ALI and to explore its mechanism of action. MATERIALS AND METHODS Ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used to analyze the chemical components of RYN. 7.5 mg/kg LPS was administered to induce ALI in rats. RYN was administered by gavage at doses of 2 ml/kg, 4 ml/kg or 8 ml/kg every 8 h for a total of 6 doses. Observations included lung histomorphology, lung wet/dry (W/D) weight ratio, lung permeability index (LPI), HE staining, Wright-Giemsa staining. ELISA was performed to detect the levels of TNF-α, IL-6, IL-10, Arg-1,UDPG. Immunohistochemical staining detected IL-6, F4/80 expression. ROS, MDA, SOD, GSH/GSSG were detected in liver tissues. Multiple omics techniques were used to predict the potential mechanism of action of RYN, which was verified by in vivo closure experiments. Immunofluorescence staining detected the co-expression of CD86 and CD206, CD86 and P2Y14, CD86 and UGP2 in liver tissues. qRT-PCR detected the mRNA levels of UGP2, P2Y14 and STAT1, and immunoblotting detected the protein expression of UGP2, P2Y14, STAT1, p-STAT1. RESULTS RYN was detected to contain 1366 metabolites, some of the metabolites with high levels have anti-inflammatory, antibacterial, antiviral and antioxidant properties. RYN (2, 4, and 8 ml/kg) exerted dose-dependent therapeutic effects on the ALI rats, by reducing inflammatory cell infiltration and oxidative stress damage, inhibiting CD86 expression, decreasing TNF-α and IL-6 levels, and increasing IL-10 and Arg-1 levels. Transcriptomics and proteomics showed that glucose metabolism provided the pathway for the anti-ALI properties of RYN and that RYN inhibited lung glycogen production and distribution. Immunofluorescence co-staining showed that RYN inhibited CD86 and UGP2 expressions. In vivo blocking experiments revealed that blocking glycogen synthesis reduced UDPG content, inhibited P2Y14 and CD86 expressions, decreased P2Y14 and STAT1 mRNA and protein expressions, reduced STAT1 protein phosphorylation expression, and had the same therapeutic effect as RYN. CONCLUSION RYN inhibits M1 macrophage polarization to alleviate ALI. Blocking glycogen synthesis and inhibiting the UDPG/P2Y14/STAT1 signaling pathway may be its molecular mechanism.
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Affiliation(s)
- Zhipeng Yan
- Departments of Infectious Disease, The Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, PR China
| | - Fanpu Ji
- Department of Infectious Diseases, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710004, PR China
| | - Ruijuan Yan
- Departments of Infectious Disease, The Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, PR China; Key Laboratory of Gastrointestinal Diseases and Prescriptions in Shaanxi Province, Shaanxi University of Chinese Medicine, Xianyang, 712046, PR China
| | - Junzhe Jiao
- Departments of Infectious Disease, The Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, PR China; Key Laboratory of Gastrointestinal Diseases and Prescriptions in Shaanxi Province, Shaanxi University of Chinese Medicine, Xianyang, 712046, PR China
| | - Wenba Wang
- College of Basic Medicine, Shaanxi University of Chinese Medicine, Xianyang, 712046, PR China
| | - Miaomiao Zhang
- Departments of Infectious Disease, The Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, PR China
| | - Fenhong Li
- Departments of Infectious Disease, The Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, PR China
| | - Yunyu Zhao
- Department of Infectious Diseases, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710004, PR China
| | - Zhanjie Chang
- Departments of Infectious Disease, The Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, PR China; Key Laboratory of Gastrointestinal Diseases and Prescriptions in Shaanxi Province, Shaanxi University of Chinese Medicine, Xianyang, 712046, PR China
| | - Shuguang Yan
- College of Basic Medicine, Shaanxi University of Chinese Medicine, Xianyang, 712046, PR China; Key Laboratory of Gastrointestinal Diseases and Prescriptions in Shaanxi Province, Shaanxi University of Chinese Medicine, Xianyang, 712046, PR China.
| | - Jingtao Li
- Departments of Infectious Disease, The Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, 712000, PR China; Key Laboratory of Gastrointestinal Diseases and Prescriptions in Shaanxi Province, Shaanxi University of Chinese Medicine, Xianyang, 712046, PR China.
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Yu H, Geng S, Li S, Wang Y, Ren X, Zhong D, Mo H, Yao M, Yu J, Li Y, Wang L. The AMPK and AKT/GSK3β pathways are involved in recombinant proteins fibroblast growth factor 1 (rFGF1 and rFGF1a) improving glycolipid metabolism in rainbow trout ( Oncorhynchus mykiss) fed a high carbohydrate diet. Anim Nutr 2024; 17:11-24. [PMID: 38444689 PMCID: PMC10912841 DOI: 10.1016/j.aninu.2023.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 09/30/2023] [Accepted: 10/15/2023] [Indexed: 03/07/2024]
Abstract
Fibroblast growth factor 1 (FGF1) regulates vertebrate cell growth, proliferation and differentiation, and energy metabolism. In this study, we cloned rainbow trout (Oncorhynchus mykiss) fgf1 and fgf1a, prepared their recombinant proteins (rFGF1 and rFGF1a), and described the molecular mechanisms by which they improve glycolipid metabolism in carnivorous fish. A 31-d feeding trial was conducted to investigate whether they could enhance glycolipid metabolism in rainbow trout on high-carbohydrate diets (HCD). A total of 720 rainbow trout (8.9 ± 0.5 g) were equally divided into 4 groups: the chow diet (CD) group injected with PBS, the HCD group injected with PBS, the HCD group injected with rFGF1 (400 ng/g body weight), and the HCD group injected with rFGF1a (400 ng/g body weight). The results showed that short-term HCD had a significant positive effect on the specific growth rate (SGR) of rainbow trout (P < 0.05). However, it led to an increase in crude fat, serum triglyceride (TG) and glucose content, as well as serum glutamic pyruvic transaminase (GPT) and glutamic oxalacetic transaminase (GOT) contents (P < 0.05), suggesting a negative health effect of HCD. Nevertheless, rFGF1 and rFGF1a showed beneficial therapeutic effects. They significantly reduced the crude fat content of the liver, serum TG, GOT, and GPT contents caused by HCD (P < 0.05). The upregulation in atgl, hsl, and acc2 mRNAs implied the promotion of TG catabolism. Moreover, rFGF1 and rFGF1a contributed to promoting lipolysis by activating the AMPK pathway and reducing lipid accumulation in the liver caused by HCD. In addition, the rFGF1 and rFGF1a-treated groups significantly reduced serum glucose levels and elevated hepatic glycogen content under HCD, and increased glucose uptake by hepatocytes. We observed a decrease in mRNA levels for pepck, g6pase, and pygl, along with an increase in mRNA levels for gys, glut2, and gk in the liver. Furthermore, these proteins regulated hepatic gluconeogenesis and glycogen synthesis by increasing the phosphorylation level of AKT, ultimately leading to an increase in GSK3β phosphorylation. In conclusion, this study demonstrates that rFGF1 and rFGF1a can enhance lipolysis and glucose utilization in rainbow trout by activating the AMPK pathway and AKT/GSK3β axis.
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Affiliation(s)
- Huixia Yu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Shuo Geng
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Shuai Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yingwei Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xin Ren
- Meixian Aquaculture Farm of Shitouhe Reservoir Administration, Xianyang, Shaanxi, 712000, China
| | - Debin Zhong
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Haolin Mo
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Mingxing Yao
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Jiajia Yu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yang Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Lixin Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
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Nie H, Hu X, Xiong H, Zeng L, Chen W, Su T. Change and pathological significance of glycogen content in oral squamous cell carcinoma and oral submucous fibrosis. Tissue Cell 2024; 87:102337. [PMID: 38430849 DOI: 10.1016/j.tice.2024.102337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 02/18/2024] [Accepted: 02/22/2024] [Indexed: 03/05/2024]
Abstract
OBJECTIVE This study aimed to investigate the change and pathological significance of glycogen content in oral squamous cell carcinoma (OSCC) and oral submucous fibrosis (OSF). METHODS AND MATERIALS 13 normal oral mucosa (NOM), 12 OSF mucosa, and 35 pairs of OSCC tissues and their corresponding adjacent mucosa tissues (AT) were collected from Xiangya Hospital for PAS staining to detect glycogen. Transcriptome sequencing data from OSCC were used to compare glycogen metabolism gene expression differences. Kaplan-Meier method was conducted to estimate Recurrence-free survival (RFS). RESULTS Glycogen levels were lower in OSF than in NOM and lower in OSCC than in AT. Transcriptome sequencing data analysis showed the expression of most glycogenolysis genes was increased and the expression of glycogen synthesis genes including PPP1R3C and GBE1 was decreased in OSCC tissues. High glycogen level was correlated with poor prognosis in OSCC patients under the background of OSF. CONCLUSION Glycogen may be used as a potential diagnostic biomolecule for OSF and OSCC, as well as a potential prognostic factor for OSCC in the context of OSF.
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Affiliation(s)
- Huanquan Nie
- Department of Oral and Maxillofacial Surgery, Centre of Stomatology, Xiangya Hospital, Central South University, Changsha, Hunan, China; Research Center of Oral and Maxillofacial Tumor, Xiangya Hospital, Central South University, Changsha, Hunan, China; Institute of Oral Cancer and Precancerous Lesions, Central South University, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Changsha, Hunan, China
| | - Xin Hu
- Department of Oral and Maxillofacial Surgery, Centre of Stomatology, Xiangya Hospital, Central South University, Changsha, Hunan, China; Research Center of Oral and Maxillofacial Tumor, Xiangya Hospital, Central South University, Changsha, Hunan, China; Institute of Oral Cancer and Precancerous Lesions, Central South University, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Changsha, Hunan, China
| | - Haofeng Xiong
- Department of Oral and Maxillofacial Surgery, Centre of Stomatology, Xiangya Hospital, Central South University, Changsha, Hunan, China; Research Center of Oral and Maxillofacial Tumor, Xiangya Hospital, Central South University, Changsha, Hunan, China; Institute of Oral Cancer and Precancerous Lesions, Central South University, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Changsha, Hunan, China
| | - Liujun Zeng
- Department of Oral and Maxillofacial Surgery, Centre of Stomatology, Xiangya Hospital, Central South University, Changsha, Hunan, China; Research Center of Oral and Maxillofacial Tumor, Xiangya Hospital, Central South University, Changsha, Hunan, China; Institute of Oral Cancer and Precancerous Lesions, Central South University, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Changsha, Hunan, China
| | - Wenxin Chen
- Department of Oral and Maxillofacial Surgery, Centre of Stomatology, Xiangya Hospital, Central South University, Changsha, Hunan, China; Research Center of Oral and Maxillofacial Tumor, Xiangya Hospital, Central South University, Changsha, Hunan, China; Institute of Oral Cancer and Precancerous Lesions, Central South University, China; Department of Orthodontics, Shanghai Huangpu District Dental Disease Prevention and Treatment Institute, Shanghai, China.
| | - Tong Su
- Department of Oral and Maxillofacial Surgery, Centre of Stomatology, Xiangya Hospital, Central South University, Changsha, Hunan, China; Research Center of Oral and Maxillofacial Tumor, Xiangya Hospital, Central South University, Changsha, Hunan, China; Institute of Oral Cancer and Precancerous Lesions, Central South University, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Changsha, Hunan, China.
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Deng A, Wang Y, Huang K, Xie P, Mo P, Liu F, Chen J, Chen K, Wang Y, Xiao B. Artichoke (Cynara scolymus L.) water extract alleviates palmitate-induced insulin resistance in HepG2 hepatocytes via the activation of IRS1/PI3K/AKT/FoxO1 and GSK-3β signaling pathway. BMC Complement Med Ther 2023; 23:460. [PMID: 38102588 PMCID: PMC10722847 DOI: 10.1186/s12906-023-04275-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 11/23/2023] [Indexed: 12/17/2023] Open
Abstract
BACKGROUND Artichoke (Cynara scolymus L.) is a typical element of a traditional Mediterranean diet and has potential health advantages for insulin resistance (IR) and type 2 diabetes mellitus (T2DM). This study aims to evaluate the effect and underlying mechanism of artichoke water extract (AWE) on palmitate (PA)-induced IR in human hepatocellular carcinoma (HepG2) cells. METHODS The effect of AWE on cell viability was determined using CCK8 assay. Cellular glucose uptake, glucose consumption, glucose production, and glycogen content were assessed after AWE treatment. The gene expression and protein levels were examined by real-time polymerase chain reaction (qRT-PCR) and western blotting. RESULTS The results showed that AWE dose-dependently increased cell viability in IR HepG2 cells (P < 0.01). AWE treatment significantly promoted glucose uptake and consumption, decreased glucose production, and increased the cellular glycogen content in IR HepG2 cells (P < 0.01). Mechanistically, AWE elevated the phosphorylation and total protein levels of major insulin signaling molecules in IR HepG2 cells, which resulted in a decrease in the expression of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) and the inhibition of glycogen synthase (GS) phosphorylation in IR HepG2 cells. Furthermore, the protective effect of AWE on IR HepG2 cells might be ascribed to the inhibition of the endoplasmic reticulum (ER) stress. CONCLUSION We conclude that AWE may improve glucose metabolism by regulating IRS1/PI3K/AKT/FoxO1 and GSK-3β signaling associated with the inhibition of ER stress in IR HepG2 cells induced by PA.
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Affiliation(s)
- Aihua Deng
- Key Laboratory of Agricultural Products Processing and Food Safety in Hunan Higher Education; Science and Technology Innovation Team for Efficient Agricultural Production and Deep Processing at General University in Hunan Province; Human Provincial Engineering Research Center for Fresh Wet Rice Noodels; College of Life and Environmental Science, Hunan University of Arts and Science, Changde, 415000, China
| | - Yun Wang
- Key Laboratory of Agricultural Products Processing and Food Safety in Hunan Higher Education; Science and Technology Innovation Team for Efficient Agricultural Production and Deep Processing at General University in Hunan Province; Human Provincial Engineering Research Center for Fresh Wet Rice Noodels; College of Life and Environmental Science, Hunan University of Arts and Science, Changde, 415000, China
| | - Kerui Huang
- Key Laboratory of Agricultural Products Processing and Food Safety in Hunan Higher Education; Science and Technology Innovation Team for Efficient Agricultural Production and Deep Processing at General University in Hunan Province; Human Provincial Engineering Research Center for Fresh Wet Rice Noodels; College of Life and Environmental Science, Hunan University of Arts and Science, Changde, 415000, China
| | - Peng Xie
- Key Laboratory of Agricultural Products Processing and Food Safety in Hunan Higher Education; Science and Technology Innovation Team for Efficient Agricultural Production and Deep Processing at General University in Hunan Province; Human Provincial Engineering Research Center for Fresh Wet Rice Noodels; College of Life and Environmental Science, Hunan University of Arts and Science, Changde, 415000, China
| | - Ping Mo
- Key Laboratory of Agricultural Products Processing and Food Safety in Hunan Higher Education; Science and Technology Innovation Team for Efficient Agricultural Production and Deep Processing at General University in Hunan Province; Human Provincial Engineering Research Center for Fresh Wet Rice Noodels; College of Life and Environmental Science, Hunan University of Arts and Science, Changde, 415000, China
| | - Fengying Liu
- Key Laboratory of Agricultural Products Processing and Food Safety in Hunan Higher Education; Science and Technology Innovation Team for Efficient Agricultural Production and Deep Processing at General University in Hunan Province; Human Provincial Engineering Research Center for Fresh Wet Rice Noodels; College of Life and Environmental Science, Hunan University of Arts and Science, Changde, 415000, China
| | - Jun Chen
- Sanjin Group Hunan Sanjin Pharmaceutical Co., Ltd, Changde, 415000, China
| | - Kaiyi Chen
- Sanjin Group Hunan Sanjin Pharmaceutical Co., Ltd, Changde, 415000, China
| | - Yun Wang
- National Clinical Research Center for Hematologic Diseases, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, Soochow University, Suzhou, P. R. China.
| | - Bing Xiao
- Institute for Development and Regenerative Cardiovascular Medicine, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China.
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Yang S, Yang G, Wang X, Li L, Li Y, Xiang J, Kang L, Liang Z. MicroRNA-92b in the skeletal muscle regulates exercise capacity via modulation of glucose metabolism. J Cachexia Sarcopenia Muscle 2023; 14:2925-2938. [PMID: 37985354 PMCID: PMC10751421 DOI: 10.1002/jcsm.13377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 09/19/2023] [Accepted: 09/25/2023] [Indexed: 11/22/2023] Open
Abstract
BACKGROUND Exercise mimetics is a proposed class of therapeutics that specifically mimics or enhances the therapeutic effects of exercise. Muscle glycogen and lactate extrusion are critical for physical performance. The mechanism by which glycogen and lactate metabolism are manipulated during exercise remains unclear. This study aimed to assess the effect of miR-92b on the upregulation of exercise training-induced physical performance. METHODS Adeno-associated virus (AAV)-mediated skeletal muscle miR-92b overexpression in C57BLKS/J mice, and global knockout of miR-92b mice were used to explore the function of miR-92b in glycogen and lactate metabolism in skeletal muscle. AAV-mediated UGP2 or MCT4 knockdown in WT or miR-92 knockout mice was used to confirm whether miR-92b regulates glycogen and lactate metabolism in skeletal muscle through UGP2 and MCT4. Body weight, muscle weight, grip strength, running time and distance to exhaustion, and muscle histology were assessed. The expression levels of muscle mass-related and function-related proteins were analysed by immunoblotting or immunostaining. RESULTS Global knockout of miR-92b resulted in normal body weight and insulin sensitivity, but higher glycogen content before exercise exhaustion (0.8538 ± 0.0417 vs. 1.043 ± 0.040, **P = 0.0087), lower lactate levels after exercise exhaustion (4.133 ± 0.2589 vs. 3.207 ± 0.2511, *P = 0.0279), and better exercise capacity (running distance to exhaustion, 3616 ± 86.71 vs. 4231 ± 90.29, ***P = 0.0006; running time to exhaustion, 186.8 ± 8.027 vs. 220.8 ± 3.156, **P = 0.0028), as compared with those observed in the control mice. Mice skeletal muscle overexpressing miR-92b (both miR-92b-3p and miR-92b-5p) displayed lower glycogen content before exercise exhaustion (0.6318 ± 0.0231 vs. 0.535 ± 0.0194, **P = 0.0094), and higher lactate accumulation after exercise exhaustion (4.5 ± 0.2394 vs. 5.467 ± 0.1892, *P = 0.01), and poorer exercise capacity (running distance to exhaustion, 4005 ± 81.65 vs. 3228 ± 149.8, ***P<0.0001; running time to exhaustion, 225.5 ± 7.689 vs. 163 ± 6.476, **P = 0.001). Mechanistic analysis revealed that miR-92b-3p targets UDP-glucose pyrophosphorylase 2 (UGP2) expression to inhibit glycogen synthesis, while miR-92b-5p represses lactate extrusion by directly target monocarboxylate transporter 4 (MCT4). Knockdown of UGP2 and MCT4 reversed the effects observed in the absence of miR-92b in vivo. CONCLUSIONS This study revealed regulatory pathways, including miR-92b-3p/UGP2/glycogen synthesis and miR-92b-5p/MCT4/lactate extrusion, which could be targeted to control exercise capacity.
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Affiliation(s)
- Shu Yang
- Department of Geriatrics, Shenzhen People's Hospital (The Second Clinical Medical CollegeJinan UniversityGuangzhouChina
- The First Affiliated HospitalSouthern University of Science and TechnologyShenzhenChina
- Guangdong Provincial Clinical Research Center for Geriatrics, Shenzhen Clinical Research Centre for GeriatricsShenzhen People's HospitalShenzhenChina
| | - Guangyan Yang
- Department of Geriatrics, Shenzhen People's Hospital (The Second Clinical Medical CollegeJinan UniversityGuangzhouChina
- Guangdong Provincial Clinical Research Center for Geriatrics, Shenzhen Clinical Research Centre for GeriatricsShenzhen People's HospitalShenzhenChina
| | - Xinyu Wang
- Department of Geriatrics, Shenzhen People's Hospital (The Second Clinical Medical CollegeJinan UniversityGuangzhouChina
- Guangdong Provincial Clinical Research Center for Geriatrics, Shenzhen Clinical Research Centre for GeriatricsShenzhen People's HospitalShenzhenChina
| | - Lixing Li
- Department of Geriatrics, Shenzhen People's Hospital (The Second Clinical Medical CollegeJinan UniversityGuangzhouChina
- Guangdong Provincial Clinical Research Center for Geriatrics, Shenzhen Clinical Research Centre for GeriatricsShenzhen People's HospitalShenzhenChina
| | - Yanchun Li
- Department of Geriatrics, Shenzhen People's Hospital (The Second Clinical Medical CollegeJinan UniversityGuangzhouChina
- Guangdong Provincial Clinical Research Center for Geriatrics, Shenzhen Clinical Research Centre for GeriatricsShenzhen People's HospitalShenzhenChina
| | - Jiaqing Xiang
- Department of Geriatrics, Shenzhen People's Hospital (The Second Clinical Medical CollegeJinan UniversityGuangzhouChina
- Guangdong Provincial Clinical Research Center for Geriatrics, Shenzhen Clinical Research Centre for GeriatricsShenzhen People's HospitalShenzhenChina
| | - Lin Kang
- Department of Geriatrics, Shenzhen People's Hospital (The Second Clinical Medical CollegeJinan UniversityGuangzhouChina
- Guangdong Provincial Clinical Research Center for Geriatrics, Shenzhen Clinical Research Centre for GeriatricsShenzhen People's HospitalShenzhenChina
- The Biobank of National Innovation Center for Advanced Medical DevicesShenzhen People's HospitalShenzhenChina
| | - Zhen Liang
- Department of Geriatrics, Shenzhen People's Hospital (The Second Clinical Medical CollegeJinan UniversityGuangzhouChina
- Guangdong Provincial Clinical Research Center for Geriatrics, Shenzhen Clinical Research Centre for GeriatricsShenzhen People's HospitalShenzhenChina
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Chang YR, Cheng WC, Hsiao YC, Su GW, Lin SJ, Wei YS, Chou HC, Lin HP, Lin GY, Chan HL. Links between oral microbiome and insulin resistance: Involvement of MAP kinase signaling pathway. Biochimie 2023; 214:134-144. [PMID: 37442534 DOI: 10.1016/j.biochi.2023.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 06/29/2023] [Accepted: 06/30/2023] [Indexed: 07/15/2023]
Abstract
Oral dysbiosis contributes to periodontitis and has implications for systemic diseases. Diabetes mellitus is a common metabolic disorder characterized by impaired glucose regulation. AMP-activated protein kinase (AMPK) plays a vital role in regulating glucose uptake and glycogenesis in the liver. This study aimed to investigate the association between periodontal bacteria and diabetes mellitus. A clinical trial was conducted to explore the association between oral bacteria and hyperglycemia. Additionally, we elucidated the molecular mechanisms by which periodontal bacteria cause insulin resistance. In the clinical trial, we discovered significant alterations in the expression levels of Fusobacterium nucleatum (Fn) and Tannerella forsythia (Tf) in patients with diabetes compared with healthy controls. Furthermore, Fn and Tf levels positively correlated with fasting blood glucose and glycated hemoglobin (HbA1C) levels. Moreover, we explored and elucidated the molecular mechanism by which Fusobacterium nucleatum culture filtrate (FNCF) induces cytokine release via the Toll-like receptor 2 (TLR2) signaling pathway in human gingival epithelial Smulow-Glickman (S-G) cells. This study investigated the effects of cytokines on insulin resistance pathways in liver cells. The use of an extracellular signal-regulated kinase (ERK) inhibitor (U0126) demonstrated that FNCF regulates the insulin receptor substrate 1 and protein kinase B (IRS1/AKT) signaling pathway, which affects key proteins involved in hepatic glycogen synthesis, including glycogen synthase kinase-3 beta (GSK3β) and glycogen synthase (GS), ultimately leading to insulin resistance. These findings suggest that ERK plays a crucial role in hepatocyte insulin resistance.
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Affiliation(s)
- Yi-Ru Chang
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan; General Biologicals Corporation, Hsinchu, Taiwan
| | - Wen-Chi Cheng
- SDGs Teaching and Research Headquarters, Tzu Chi University, Hualien, Taiwan
| | - Ya-Chun Hsiao
- Department of Endocrinology and Metabolism, Hsinchu Mackay Memorial Hospital, Hsinchu, Taiwan
| | - Guan-Wei Su
- Dental Department of Hsinchu Mackay Memorial Hospital, Hsinchu, Taiwan
| | - Shan-Jen Lin
- Dental Department of Hsinchu Mackay Memorial Hospital, Hsinchu, Taiwan
| | - Yu-Shan Wei
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Hsiu-Chuan Chou
- Institute of Analytical and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | | | - Guan-Yu Lin
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Hong-Lin Chan
- Department of Medical Science and Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, Taiwan.
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Zhong J, Tian L, Gou Y, Zhao P, Dong X, Guo M, Zhao G, Li A, Hao A, He TC, Fan J. BMP4 upregulates glycogen synthesis through the SMAD/SLC2A1 (GLUT1) signaling axis in hepatocellular carcinoma (HCC) cells. Cancer Metab 2023; 11:9. [PMID: 37443106 DOI: 10.1186/s40170-023-00310-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 06/26/2023] [Indexed: 07/15/2023] Open
Abstract
BACKGROUND Excessive hepatic glycogen accumulation benefits tumorigenesis and cancer cell survival. We previously reported that BMP4 has the strongest ability to promote glycogenesis among the 14 BMPs in hepatocytes and augmented hepatocellular carcinoma (HCC) cell survival under hypoxia and hypoglycemia conditions by promoting the glycolysis pathway. However, the mechanism underlying BMP4's effect on glycogenesis in HCC remains elusive. METHODS The expression of BMP4 and SLC2A1 were acquired by analyzing the TCGA-LIHC dataset, as well as by immunohistochemical analysis of the 40 pairs of human HCC samples and para-tumor tissues. Gene expressions were detected by qPCR, immunoflurorescence staining, and Western blotting. Overexpression and silencing of BMP4 were accomplished through adenoviruses Ad-B4 and Ad-siB4 infection. Hepatic glycogen was detected by PAS staining. SLC2A1 (GLUT1) function was blocked by the inhibitor BAY-876. ChIP assay was used to determine the binding of SMADs to the promoter region of SLC2A1 in HCC cells. Lastly, the in vivo effect of BMP4-regulated SLC2A1 on HCC tumor growth was assessed in a xenograft model of HCC. RESULTS The elevated expression of BMP4 in HCC tumor tissues was highly correlated with hepatic glycogen accumulation in clinical samples. SLC2A1 was highly expressed in HCC tumor tissue and correlated with clinical stage and prognosis. Exogenous BMP4 augmented glycogen accumulation and upregulated the expression of glycogen synthesis-related genes in Huh7 and HepG2 cells, both of which were effectively blunted by SLC2A1inhibitor BAY-876. In mechanism, BMP4 activated SMAD5 to regulate the promoter of SLC2A1to enhance its expression. The in vivo xenograft experiments revealed that BMP4 promoted glycogen accumulation and tumor growth, which were effectively diminished by BAY-876. CONCLUSION These results demonstrate that BMP4 upregulates glycogen synthesis through the SMAD/SLC2A1 (GLUT1) signaling axis in HCC cells, which may be exploited as novel therapeutic targets for HCC treatment.
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Affiliation(s)
- Jiamin Zhong
- Ministry of Education Key Laboratory of Diagnostic Medicine, Chongqing, China
- Department of Clinical Biochemistry, College of Laboratory Medicine, Chongqing Medical University, No. 1 Medical School Road, Yuzhong District, Chongqing, 400016, China
- Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, 5841 South Maryland Avenue, MC 3079, Chicago, IL, 60637, USA
| | - Luyao Tian
- Ministry of Education Key Laboratory of Diagnostic Medicine, Chongqing, China
- Department of Clinical Biochemistry, College of Laboratory Medicine, Chongqing Medical University, No. 1 Medical School Road, Yuzhong District, Chongqing, 400016, China
| | - Yannian Gou
- Ministry of Education Key Laboratory of Diagnostic Medicine, Chongqing, China
- Department of Clinical Biochemistry, College of Laboratory Medicine, Chongqing Medical University, No. 1 Medical School Road, Yuzhong District, Chongqing, 400016, China
- Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, 5841 South Maryland Avenue, MC 3079, Chicago, IL, 60637, USA
| | - Piao Zhao
- Ministry of Education Key Laboratory of Diagnostic Medicine, Chongqing, China
- Department of Clinical Biochemistry, College of Laboratory Medicine, Chongqing Medical University, No. 1 Medical School Road, Yuzhong District, Chongqing, 400016, China
- Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, 5841 South Maryland Avenue, MC 3079, Chicago, IL, 60637, USA
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Xiangyu Dong
- Ministry of Education Key Laboratory of Diagnostic Medicine, Chongqing, China
- Department of Clinical Biochemistry, College of Laboratory Medicine, Chongqing Medical University, No. 1 Medical School Road, Yuzhong District, Chongqing, 400016, China
| | - Meichun Guo
- Ministry of Education Key Laboratory of Diagnostic Medicine, Chongqing, China
- Department of Clinical Biochemistry, College of Laboratory Medicine, Chongqing Medical University, No. 1 Medical School Road, Yuzhong District, Chongqing, 400016, China
| | - Guozhi Zhao
- Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, 5841 South Maryland Avenue, MC 3079, Chicago, IL, 60637, USA
- Department of Urology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Aohua Li
- Ministry of Education Key Laboratory of Diagnostic Medicine, Chongqing, China
- Department of Clinical Biochemistry, College of Laboratory Medicine, Chongqing Medical University, No. 1 Medical School Road, Yuzhong District, Chongqing, 400016, China
| | - Ailing Hao
- Ministry of Education Key Laboratory of Diagnostic Medicine, Chongqing, China
- Department of Clinical Biochemistry, College of Laboratory Medicine, Chongqing Medical University, No. 1 Medical School Road, Yuzhong District, Chongqing, 400016, China
| | - Tong-Chuan He
- Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, 5841 South Maryland Avenue, MC 3079, Chicago, IL, 60637, USA.
| | - Jiaming Fan
- Ministry of Education Key Laboratory of Diagnostic Medicine, Chongqing, China.
- Department of Clinical Biochemistry, College of Laboratory Medicine, Chongqing Medical University, No. 1 Medical School Road, Yuzhong District, Chongqing, 400016, China.
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8
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Liang M, Wang L, Wang W. The 15-hydroxyprostaglandin dehydrogenase inhibitor SW033291 ameliorates abnormal hepatic glucose metabolism through PGE 2-EP4 receptor-AKT signaling in a type 2 diabetes mellitus mouse model. Cell Signal 2023; 108:110707. [PMID: 37164143 DOI: 10.1016/j.cellsig.2023.110707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 04/21/2023] [Accepted: 05/03/2023] [Indexed: 05/12/2023]
Abstract
Type 2 diabetes mellitus (T2DM) is associated with high rates of morbidity and mortality worldwide. Prostaglandin E2 (PGE2) is a lipid signaling molecule that can ameliorate the symptoms of some metabolic diseases, including T2DM, and improve tissue repair and regeneration. Although SW033291 can increase PGE2 levels through its action as a small molecule inhibitor of the PGE2-degrading enzyme 15-hydroxyprostaglandin dehydrogenase, its effects on T2DM remain unclear. In the present study, we evaluated whether SW033291 treatment exerts a protective effect against T2DM and explored the underlying mechanisms. A T2DM mouse model was established using a high-fat diet combined with streptozotocin treatment. Palmitic acid-treated LO2 cells were used as an insulin-resistant cell model. SW033291 treatment reduced body weight and fasting blood glucose levels as well as serum triglyceride, total cholesterol, and low-density lipoprotein cholesterol levels in vivo. In addition to ameliorating glucose and insulin tolerance, SW033291 treatment reversed the T2DM-induced decrease in glycogen synthesis and increase in gluconeogenesis in the liver. Furthermore, SW033291 administration increased hepatic glycogen synthase kinase 3 beta (GSK3β) phosphorylation levels to promote glycogen synthesis. SW033291 treatment also inhibited gluconeogenesis by upregulating AKT serine/threonine kinase (AKT) and forkhead box O1 (FOXO1) phosphorylation and reducing glucose-6-phosphatase and phosphoenolpyruvate carboxykinase 1 expression in the livers of T2DM model mice. Additionally, SW033291 treatment improved abnormal hepatic glucose metabolism through the PGE2-EP4 receptor-AKT-GSK3β/FOXO1 signaling pathway in vitro. These results suggest a novel role of SW033291 in improving T2DM and support its potential as a novel therapeutic agent.
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Affiliation(s)
- Mingjie Liang
- Traditional Chinese Medicine Research Institute, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province, China; Guangdong Provincial Research Center of Integration of Traditional Chinese Medicine and Western Medicine in Metabolic Diseases, Guangzhou, Guangdong Province, China; Key Laboratory of Glucolipid Metabolic Diseases, Ministry of Education, Guangzhou, Guangdong Province, China; Guangdong Provincial TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province, China
| | - Lexun Wang
- Traditional Chinese Medicine Research Institute, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province, China; Guangdong Provincial Research Center of Integration of Traditional Chinese Medicine and Western Medicine in Metabolic Diseases, Guangzhou, Guangdong Province, China; Key Laboratory of Glucolipid Metabolic Diseases, Ministry of Education, Guangzhou, Guangdong Province, China; Guangdong Provincial TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province, China
| | - Weixuan Wang
- Traditional Chinese Medicine Research Institute, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province, China; Guangdong Provincial Research Center of Integration of Traditional Chinese Medicine and Western Medicine in Metabolic Diseases, Guangzhou, Guangdong Province, China; Key Laboratory of Glucolipid Metabolic Diseases, Ministry of Education, Guangzhou, Guangdong Province, China; Guangdong Provincial TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou, Guangdong Province, China.
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9
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Kyei-Barffour I, Kwarkoh RKB, Arthur OD, Akwetey SA, Acheampong DO, Aboagye B, Brah AS, Amponsah IK, Adokoh CK. Alkaloidal extract from Zanthoxylum zanthoxyloides stimulates insulin secretion in normoglycemic and nicotinamide/streptozotocin-induced diabetic rats. Heliyon 2021; 7:e07452. [PMID: 34278033 PMCID: PMC8267442 DOI: 10.1016/j.heliyon.2021.e07452] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/27/2021] [Accepted: 06/28/2021] [Indexed: 11/18/2022] Open
Abstract
Introduction Increase in the prevalence of type-2 diabetes in Sub-Sahara Africa has created the need for robust treatment and management programs. However, an effective diabetes management program requires a high annual budget that most countries in this region cannot afford. That said, various plants and plant products in this region have either been confirmed and/or ethnopharmacologically used for the management of type-2 diabetes. Aim To investigate the antidiabetic and insulin secretory effects of an alkaloidal extract derived from Zanthoxylum zanthoxyloides in normoglycemic and experimental diabetic rats. Materials and methods Alkaloidal extract was prepared from leaves of Zanthoxylum zanthoxyloides (ZZAE). Nicotinamide/streptozotocin-induced type-2 diabetes was modeled in male Sprague Dawley rats weighing between 130 to 150 g. The experimental diabetic rats were grouped into six treatment groups [Model, 20% Tween20, chlorpropamide, and ZZAE (50, 100, and 150 mg/kg)], and one control group. Fasting blood glucose (FBG), and body weight were measured weekly. Rats were sacrificed 2 days after treatment under chloroform anesthesia to collect blood samples and to isolate major organs for biochemical, and histological analyses respectively. Islets of Langerhans were isolated from normoglycemic rats and co-cultured with ZZAE and chlorpropamide (10 μg/mL) to assess the insulin secretory effect of ZZAE. Results ZZAE improved glucose kinetics curve in normoglycemic (p < 0.001) and experimental diabetic rats (p < 0.05) compared to the model. ZZAE (100 and 150 mg/kg) restored islets population, and improved kidney, and liver, histoarchitecture. ZZAE (150 mg/kg) improved post-treatment serum insulin levels compared to the model group (p < 0.001) and the Chlorpropamide group (p < 0.05). ZZAE also restored glycogen synthesis in skeletal muscles of experimental diabetic rats and stimulated insulin secretion in pancreatic islets of Langerhans isolated from normoglycemic rats. Conclusion These results showed that ZZAE has active alkaloids that can be explored for diabetes management.
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Affiliation(s)
- Isaac Kyei-Barffour
- Department of Biomedical Sciences, School of Allied Health Sciences, College of Health and Allied Sciences, University of Cape Coast, Ghana
- Corresponding author.
| | - Roselind Kyei Baah Kwarkoh
- Department of Physician Assistant Studies, School of Allied Health Sciences, College of Health and Allied Sciences, University of Cape Coast, Ghana
| | - Ophelia Duke Arthur
- Department of Medical Laboratory and Diagnostics, Euracare Advance Diagnostic Center, Labone, Accra, Ghana
| | - Samuel Addo Akwetey
- Department of Biomedical Sciences, School of Allied Health Sciences, College of Health and Allied Sciences, University of Cape Coast, Ghana
| | - Desmond Omane Acheampong
- Department of Biomedical Sciences, School of Allied Health Sciences, College of Health and Allied Sciences, University of Cape Coast, Ghana
| | - Benjamin Aboagye
- Department of Forensic Sciences, School of Biological Sciences, University of Cape Coast, Ghana
| | - Augustine Suurinobah Brah
- Department of Biomedical Sciences, School of Allied Health Sciences, College of Health and Allied Sciences, University of Cape Coast, Ghana
| | - Isaac Kingsley Amponsah
- Department of Pharmacognosy, Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Unkrumah University of Science and Technology, Kumasi, Ghana
| | - Christian Kweku Adokoh
- Department of Forensic Sciences, School of Biological Sciences, University of Cape Coast, Ghana
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10
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Zhao T, Wang J, He A, Wang S, Chen Y, Lu J, Lv J, Li S, Wang J, Qian M, Li H, Shen X. Mebhydrolin ameliorates glucose homeostasis in type 2 diabetic mice by functioning as a selective FXR antagonist. Metabolism 2021; 119:154771. [PMID: 33831422 DOI: 10.1016/j.metabol.2021.154771] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 03/01/2021] [Accepted: 03/28/2021] [Indexed: 02/08/2023]
Abstract
INTRODUCTION Type 2 diabetes mellitus (T2DM) is a chronic disease with hallmarks of hyperglycemia and hyperlipidemia. Long-term hyperglycemia damages the functions of multiple tissues and organs leading to a series of complications and disability or even death. Nuclear receptor farnesoid X receptor (FXR) antagonism has been recently discovered to exhibit beneficial effect on glucose metabolism in T2DM mice, although the underlying mechanisms remain unclear. Here, we performed the study on the discovery of new FXR antagonist and investigated the mechanism underlying the amelioration of FXR antagonism on glucose homeostasis in T2DM mice by using the determined FXR antagonist as a probe. METHODS FXR antagonist Mebhydrolin was discovered by screening against the lab in-house FDA approved drug library through surface plasmon resonance (SPR), microscale thermophoresis (MST), AlphaScreen, mammalian one-hybrid and transactivation assays. Activity of Mebhydrolin in improving glucose homeostasis was evaluated in db/db and HFD/STZ-induced T2DM mice, and the mechanisms governing the regulation of Mebhydrolin were investigated by assays of immunostaining, Western blot, ELISA, RT-PCR against liver tissues of both T2DM mice and the T2DM mice with liver-specific FXR knockdown injected via adeno-associated-virus AAV-FXR-RNAi and mouse primary hepatocytes. Finally, molecular docking and molecular dynamics (MD) technology-based study was performed to investigate the structural basis for the antagonistic regulation of Mebhydrolin against FXR at an atomic level. FINDINGS Mebhydrolin ameliorated blood glucose homeostasis in T2DM mice by both suppressing hepatic gluconeogenesis via FXR/miR-22-3p/PI3K/AKT/FoxO1 pathway and promoting glycogen synthesis through FXR/miR-22-3p/PI3K/AKT/GSK3β pathway. Structurally, residues L291, M332 and Y373 of FXR were required for Mebhydrolin binding to FXR-LBD, and Mebhydrolin induced H2 and H6 shifting of FXR potently affecting the regulation of the downstream target genes. CONCLUSIONS Our work has revealed a novel mode for the regulation of FXR against glucose metabolism in T2DM mice and highlighted the potential of Mebhydrolin in the treatment of T2DM.
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MESH Headings
- Animals
- Blood Glucose/drug effects
- Blood Glucose/metabolism
- Carbolines/chemistry
- Carbolines/pharmacokinetics
- Carbolines/therapeutic use
- Cells, Cultured
- Diabetes Mellitus, Experimental/chemically induced
- Diabetes Mellitus, Experimental/drug therapy
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Type 2/chemically induced
- Diabetes Mellitus, Type 2/drug therapy
- Diabetes Mellitus, Type 2/metabolism
- Gluconeogenesis/drug effects
- Gluconeogenesis/genetics
- Glucose/metabolism
- HEK293 Cells
- Homeostasis/drug effects
- Humans
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Molecular Docking Simulation
- Protein Interaction Domains and Motifs
- Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors
- Receptors, Cytoplasmic and Nuclear/chemistry
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/metabolism
- Streptozocin
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Affiliation(s)
- Tong Zhao
- School of Medicine& Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Jie Wang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Anxu He
- School of Medicine& Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Shan Wang
- School of Medicine& Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Yidi Chen
- School of Medicine& Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Jian Lu
- School of Medicine& Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Jianlu Lv
- School of Medicine& Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Shiliang Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Jiaying Wang
- School of Medicine& Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Minyi Qian
- School of Medicine& Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Honglin Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
| | - Xu Shen
- School of Medicine& Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China.
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11
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Zhang W, Gao J, Shen F, Ma X, Wang Z, Hou X, Hao E, Hou Y, Bai G. Cinnamaldehyde changes the dynamic balance of glucose metabolism by targeting ENO1. Life Sci 2020; 258:118151. [PMID: 32726661 DOI: 10.1016/j.lfs.2020.118151] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 07/21/2020] [Accepted: 07/22/2020] [Indexed: 11/21/2022]
Abstract
AIMS Hepatic glucose metabolism involves a variety of catabolic and anabolic pathways, and the dynamic balance of glucose metabolism is regulated in response to environmental and nutritional changes. The molecular mechanism of glucose metabolism in liver is complex and has not been fully elucidated so far. In this study, we hope to elucidate the target and mechanism of cinnamaldehyde (CA) in regulating glucose metabolism. MATERIALS AND METHODS Molecular image tracing and magnetic capture in combination with an alkynyl-CA probe (Al-CA) was used to show CA covalently binds to α-enolase (ENO1) in both mouse liver and HepG2 cells. Accurate metabolic flow assays subsequently demonstrated that the utilization of glycogenic amino acids and the biosynthesis of tricarboxylic acid (TCA) cycle intermediates were strengthened, which was detected using nontargeted and targeted metabolomics analyses. KEY FINDINGS Our study shows that CA covalently bonds with ENO1, which affects the stability and activity of ENO1 and changes the dynamic balance of glucose metabolism. The interruption of gluconeogenic reflux by ENO1 enhanced TCA cycle, and eventually led to a decrease in blood glucose and the improvement of mitochondrial efficiency. SIGNIFICANCE These results provide a detailed description of how CA maintains the dynamic balance of glucose utilization and improves energy metabolism.
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12
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Issac PK, Guru A, Chandrakumar SS, Lite C, Saraswathi NT, Arasu MV, Al-Dhabi NA, Arshad A, Arockiaraj J. Molecular process of glucose uptake and glycogen storage due to hamamelitannin via insulin signalling cascade in glucose metabolism. Mol Biol Rep 2020; 47:6727-6740. [PMID: 32809102 DOI: 10.1007/s11033-020-05728-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 08/10/2020] [Indexed: 12/19/2022]
Abstract
Understanding the mechanism by which the exogenous biomolecule modulates the GLUT-4 signalling cascade along with the information on glucose metabolism is essential for finding solutions to increasing cases of diabetes and metabolic disease. This study aimed at investigating the effect of hamamelitannin on glycogen synthesis in an insulin resistance model using L6 myotubes. Glucose uptake was determined using 2-deoxy-D-[1-3H] glucose and glycogen synthesis were also estimated in L6 myotubes. The expression levels of key genes and proteins involved in the insulin-signaling pathway were determined using real-time PCR and western blot techniques. The cells treated with various concentrations of hamamelitannin (20 µM to 100 µM) for 24 h showed that, the exposure of hamamelitannin was not cytotoxic to L6 myotubes. Further the 2-deoxy-D-[1-3H] glucose uptake assay was carried out in the presence of wortmannin and Genistein inhibitor for studying the GLUT-4 dependent cell surface recruitment. Hamamelitannin exhibited anti-diabetic activity by displaying a significant increase in glucose uptake (125.1%) and glycogen storage (8.7 mM) in a dose-dependent manner. The optimum concentration evincing maximum activity was found to be 100 µm. In addition, the expression of key genes and proteins involved in the insulin signaling pathway was studied to be upregulated by hamamelitannin treatment. Western blot analysis confirmed the translocation of GLUT-4 protein from an intracellular pool to the plasma membrane. Therefore, it can be conceived that hamamelitannin exhibited an insulinomimetic effect by enhancing the glucose uptake and its further conversion into glycogen by regulating glucose metabolism.
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Affiliation(s)
- Praveen Kumar Issac
- SRM Research Institute, SRM Institute of Science and Technology, Kattankulathur, Chennai, Tamil Nadu, 603 203, India
| | - Ajay Guru
- SRM Research Institute, SRM Institute of Science and Technology, Kattankulathur, Chennai, Tamil Nadu, 603 203, India
| | - Sri Snehaa Chandrakumar
- Department of Biotechnology, Anna University, BIT Campus, Tiruchirappalli, Tamil Nadu, 620 024, India
| | - Christy Lite
- Endocrine and Exposome Laboratory, Department of Zoology, Madras Christian College, Tambaram, Chennai, Tamil Nadu, 600 059, India
| | - N T Saraswathi
- Molecular Biophysics Laboratory, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, Tamil Nadu, 613 401, India
| | - Mariadhas Valan Arasu
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, 11451, Riyadh, Saudi Arabia
| | - Naif Abdullah Al-Dhabi
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, 11451, Riyadh, Saudi Arabia
| | - Aziz Arshad
- International Institute of Aquaculture and Aquatic Sciences (I-AQUAS), Universiti Putra Malaysia, Port Dickson, Negeri Sembilan, 71050, Malaysia
- Department of Aquaculture, Faculty of Agriculture, Universiti Putra Malaysia, Serdang, Selangor, 43400, Malaysia
| | - Jesu Arockiaraj
- SRM Research Institute, SRM Institute of Science and Technology, Kattankulathur, Chennai, Tamil Nadu, 603 203, India.
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Luca E, Turcekova K, Hartung A, Mathes S, Rehrauer H, Krützfeldt J. Genetic deletion of microRNA biogenesis in muscle cells reveals a hierarchical non-clustered network that controls focal adhesion signaling during muscle regeneration. Mol Metab 2020; 36:100967. [PMID: 32240622 PMCID: PMC7139120 DOI: 10.1016/j.molmet.2020.02.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 02/19/2020] [Accepted: 02/20/2020] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVE Decreased muscle mass is a major contributor to age-related morbidity, and strategies to improve muscle regeneration during ageing are urgently needed. Our aim was to identify the subset of relevant microRNAs (miRNAs) that partake in critical aspects of muscle cell differentiation, irrespective of computational predictions, genomic clustering or differential expression of the miRNAs. METHODS miRNA biogenesis was deleted in primary myoblasts using a tamoxifen-inducible CreLox system and combined with an add-back miRNA library screen. RNA-seq experiments, cellular signalling events, and glycogen synthesis, along with miRNA inhibitors, were performed in human primary myoblasts. Muscle regeneration in young and aged mice was assessed using the cardiotoxin (CTX) model. RESULTS We identified a hierarchical non-clustered miRNA network consisting of highly (miR-29a), moderately (let-7) and mildly active (miR-125b, miR-199a, miR-221) miRNAs that cooperate by directly targeting members of the focal adhesion complex. Through RNA-seq experiments comparing single versus combinatorial inhibition of the miRNAs, we uncovered a fundamental feature of this network, that miRNA activity inversely correlates to miRNA cooperativity. During myoblast differentiation, combinatorial inhibition of the five miRNAs increased activation of focal adhesion kinase (FAK), AKT, and p38 mitogen-activated protein kinase (MAPK), and improved myotube formation and insulin-dependent glycogen synthesis. Moreover, antagonizing the miRNA network in vivo following CTX-induced muscle regeneration enhanced muscle mass and myofiber formation in young and aged mice. CONCLUSION Our results provide novel insights into the dynamics of miRNA cooperativity and identify a miRNA network as therapeutic target for impaired focal adhesion signalling and muscle regeneration during ageing.
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Affiliation(s)
- Edlira Luca
- Division of Endocrinology, Diabetes, and Clinical Nutrition, University Hospital Zurich, 8091, Switzerland
| | - Katarina Turcekova
- Division of Endocrinology, Diabetes, and Clinical Nutrition, University Hospital Zurich, 8091, Switzerland; Competence Center Personalized Medicine UZH/ETH, ETH Zurich and University of Zurich, 8091, Switzerland
| | - Angelika Hartung
- Division of Endocrinology, Diabetes, and Clinical Nutrition, University Hospital Zurich, 8091, Switzerland
| | - Sebastian Mathes
- Division of Endocrinology, Diabetes, and Clinical Nutrition, University Hospital Zurich, 8091, Switzerland; Zurich Center for Integrative Human Physiology, University of Zurich, 8091, Switzerland
| | - Hubert Rehrauer
- Functional Genomics Center Zurich UZH/ETH, ETH Zurich and University of Zurich, 8091, Switzerland
| | - Jan Krützfeldt
- Division of Endocrinology, Diabetes, and Clinical Nutrition, University Hospital Zurich, 8091, Switzerland; Competence Center Personalized Medicine UZH/ETH, ETH Zurich and University of Zurich, 8091, Switzerland; Zurich Center for Integrative Human Physiology, University of Zurich, 8091, Switzerland.
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14
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Olaniyi KS, Olatunji LA. Oral ethinylestradiol-levonorgestrel attenuates cardiac glycogen and triglyceride accumulation in high fructose female rats by suppressing pyruvate dehydrogenase kinase-4. Naunyn Schmiedebergs Arch Pharmacol 2018; 392:89-101. [PMID: 30276420 DOI: 10.1007/s00210-018-1568-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 09/19/2018] [Indexed: 12/16/2022]
Abstract
Fructose (FRU) intake has increased dramatically in recent decades with a corresponding increased incidence of insulin resistance (IR), particularly in young adults. The use of oral ethinylestradiol-levonorgestrel (EEL) formulation is also common among young women worldwide. The present study aimed at determining the effect of EEL on high fructose-induced cardiac triglyceride (TG) and glycogen accumulation. The study also investigated the possible involvement of pyruvate dehydrogenase kinase-4 (PDK-4) in EEL and/or high fructose metabolic effects on the heart. Ten-week-old female Wistar rats were allotted into four groups. The control, EEL, FRU, and EEL + FRU rats received distilled water (vehicle, p.o.), 1.0 μg ethinylestradiol plus 5.0 μg levonorgestrel (p.o.), 10% fructose (w/v), and 1.0 μg ethinylestradiol plus 5.0 μg levonorgestrel and 10% fructose, respectively, daily for 8 weeks. Data showed that EEL or high fructose caused IR' impaired glucose tolerance' hyperlipidemia' increased plasma lactate, lactate dehydrogenase, PDK-4, uric acid, xanthine oxidase (XO), adenosine deaminase (ADA), malondialdehyde (MDA), cardiac uric acid, TG, TG/HDL- cholesterol, glycogen synthesis, MDA, and visceral fat content and reduced glutathione. High fructose also resulted in impaired pancreatic β-cell function, hyperglycemia, and increased cardiac PDK-4, lactate synthesis, and mass. Nonetheless, these alterations were ameliorated in EEL plus high fructose rats. This study demonstrates that high fructose-induced myocardial TG and glycogen accumulation is attributable to increased PDK-4. Besides, EEL could be a useful pharmacological utility for protection against cardiac dysmetabolism by inhibiting PDK-4.
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Affiliation(s)
- Kehinde Samuel Olaniyi
- HOPE Cardiometabolic Research Team & Department of Physiology, College of Health Sciences, University of Ilorin, P.M.B. 1515, Ilorin, 240001, Nigeria
| | - Lawrence Aderemi Olatunji
- HOPE Cardiometabolic Research Team & Department of Physiology, College of Health Sciences, University of Ilorin, P.M.B. 1515, Ilorin, 240001, Nigeria.
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15
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Aziz MA, Ushirokita R, Azuma Y. Identification of Chlamydia pneumoniae candidate genes that interact with human apoptotic factor caspase-9. J GEN APPL MICROBIOL 2018; 64:253-257. [PMID: 29760350 DOI: 10.2323/jgam.2017.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Chlamydia pneumoniae is an obligate intracellular pathogen responsible for respiratory diseases, including pneumonia and bronchitis, and is highly involved in chronic diseases, including atherosclerosis, asthma, and Alzheimer's disease. We previously showed that the host apoptotic factor caspase-9 played a crucial role for chlamydial multiplication and host apoptosis inhibition by chlamydial infection. To identify chlamydial genes interacting with human caspase-9, yeast two-hybrid screening was performed and 5 chlamydial genes, including Cpj0838 and pmpG were isolated from the C. pneumoniae genomic library. Pull-down experiments showed that caspase-9 physically bound to the Cpj0838 product and chlamydial cells, which contain PmpG proteins. This study could provide a clue to understanding host-Chlamydia interactions, especially the apoptosis repression by Chlamydia infection.
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Affiliation(s)
- Md Abdul Aziz
- Graduate School of Biology-Oriented Science and Technology, Kindai University
| | - Rie Ushirokita
- Graduate School of Biology-Oriented Science and Technology, Kindai University
| | - Yoshinao Azuma
- Graduate School of Biology-Oriented Science and Technology, Kindai University
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Lassiter DG, Nylén C, Sjögren RJO, Chibalin AV, Wallberg-Henriksson H, Näslund E, Krook A, Zierath JR. FAK tyrosine phosphorylation is regulated by AMPK and controls metabolism in human skeletal muscle. Diabetologia 2018; 61:424-432. [PMID: 29022062 PMCID: PMC6449061 DOI: 10.1007/s00125-017-4451-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 08/11/2017] [Indexed: 01/28/2023]
Abstract
AIMS/HYPOTHESIS Insulin-mediated signals and AMP-activated protein kinase (AMPK)-mediated signals are activated in response to physiological conditions that represent energy abundance and shortage, respectively. Focal adhesion kinase (FAK) is implicated in insulin signalling and cancer progression in various non-muscle cell types and plays a regulatory role during skeletal muscle differentiation. The role of FAK in skeletal muscle in relation to insulin stimulation or AMPK activation is unknown. We examined the effects of insulin or AMPK activation on FAK phosphorylation in human skeletal muscle and the direct role of FAK on glucose and lipid metabolism. We hypothesised that insulin treatment and AMPK activation would have opposing effects on FAK phosphorylation and that gene silencing of FAK would alter metabolism. METHODS Human muscle was treated with insulin or the AMPK-activating compound 5-aminoimadazole-4-carboxamide ribonucleotide (AICAR) to determine FAK phosphorylation and glucose transport. Primary human skeletal muscle cells were used to study the effects of insulin or AICAR treatment on FAK signalling during serum starvation, as well as to determine the metabolic consequences of silencing the FAK gene, PTK2. RESULTS AMPK activation reduced tyrosine phosphorylation of FAK in skeletal muscle. AICAR reduced p-FAKY397 in isolated human skeletal muscle and cultured myotubes. Insulin stimulation did not alter FAK phosphorylation. Serum starvation increased AMPK activation, as demonstrated by increased p-ACCS222, concomitant with reduced p-FAKY397. FAK signalling was reduced owing to serum starvation and AICAR treatment as demonstrated by reduced p-paxillinY118. Silencing PTK2 in primary human skeletal muscle cells increased palmitate oxidation and reduced glycogen synthesis. CONCLUSIONS/INTERPRETATION AMPK regulates FAK signalling in skeletal muscle. Moreover, siRNA-mediated FAK knockdown enhances lipid oxidation while impairing glycogen synthesis in skeletal muscle. Further exploration of the interaction between AMPK and FAK may lead to novel therapeutic strategies for diabetes and other chronic conditions associated with an altered metabolic homeostasis.
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Affiliation(s)
- David G Lassiter
- Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, von Eulers väg 4a, IV, SE-171 65, Stockholm, Sweden
| | - Carolina Nylén
- Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, von Eulers väg 4a, IV, SE-171 65, Stockholm, Sweden
| | - Rasmus J O Sjögren
- Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, von Eulers väg 4a, IV, SE-171 65, Stockholm, Sweden
| | - Alexander V Chibalin
- Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, von Eulers väg 4a, IV, SE-171 65, Stockholm, Sweden
| | | | - Erik Näslund
- Division of Surgery, Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Anna Krook
- Department of Physiology and Pharmacology, Integrative Physiology, Karolinska Institutet, Stockholm, Sweden
| | - Juleen R Zierath
- Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, von Eulers väg 4a, IV, SE-171 65, Stockholm, Sweden.
- Department of Physiology and Pharmacology, Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.
- Section of Integrative Physiology, The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark.
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Tsai TW, Chang CC, Liao SF, Liao YH, Hou CW, Tsao JP, Cheng IS. Effect of green tea extract supplementation on glycogen replenishment in exercised human skeletal muscle. Br J Nutr 2017; 117:1343-50. [PMID: 28631582 DOI: 10.1017/S0007114517001374] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The purpose of this study was to investigate the effects of 8-week green tea extract (GTE) supplementation on promoting postexercise muscle glycogen resynthesis and systemic energy substrate utilisation in young college students. A total of eight healthy male participants (age: 22·0 (se 1·0) years, BMI: 24·2 (se 0·7) kg/m2, VO2max: 43·2 (se 2·4) ml/kg per min) participated in this study. GTE (500 mg/d for 8 weeks) was compared with placebo in participants in a double-blind/placebo-controlled and crossover study design with an 8-week washout period. Thereafter, all participants performed a 60-min cycling exercise (75 % VO2max) and consumed a carbohydrate-enriched meal immediately after exercise. Vastus lateralis muscle samples were collected immediately (0 h) and 3 h after exercise, and blood and gaseous samples were collected during the 3-h postexercise recovery period. An 8-week oral GTE supplementation had no effects on further promoting muscle glycogen resynthesis in exercised human skeletal muscle, but the exercise-induced muscle GLUT type 4 (GLUT4) protein content was greater in the GTE supplementation trial (P<0·05). We observed that, during the postexercise recovery period, GTE supplementation elicited an increase in energy reliance on fat oxidation compared with the placebo trial (P<0·05), although there were no differences in blood glucose and insulin responses between the two trials. In summary, 8-week oral GTE supplementation increases postexercise systemic fat oxidation and exercise-induced muscle GLUT4 protein content in response to an acute bout of endurance exercise. However, GTE supplementation has no further benefit on promoting muscle glycogen resynthesis during the postexercise period.
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Fariña AC, Hirabara S, Sain J, González M, Curi R, Bernal C. Influence of trans fatty acids on glucose metabolism in soleus muscle of rats fed diets enriched in or deprived of linoleic acid. Eur J Nutr 2017; 57:1343-1355. [PMID: 28285433 DOI: 10.1007/s00394-017-1413-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 02/19/2017] [Indexed: 11/26/2022]
Abstract
PURPOSE Industrial trans fatty acid (TFA) intake leads to impaired glucose metabolism. However, the overall effects reported are inconsistent and vary with the dietary FA composition and TFA isomer type and levels. We investigated TFA effects on glucose uptake, incorporation and oxidation, and glycogen synthesis in incubated soleus muscle under basal conditions or after treatment with insulin and/or palmitate. METHODS Male Wistar rats were fed either linoleic acid (LA)-enriched (+LA) or LA-deprived (-LA) diet, supplemented (+LA + TFA or -LA + TFA) or not with TFA, for 60 days. Soleus muscle glucose metabolism was assessed in the absence or presence of insulin and/or palmitic acid. RESULTS Under basal conditions, TFA enhanced glucose uptake and oxidation regardless of the LA status. Both TFA-supplemented groups had lower insulin response to glucose metabolism. Under insulin-stimulated conditions, TFA prevented the palmitate inhibition of muscle glucose uptake and metabolism in the +LA + TFA group. CONCLUSION Dietary TFA enhanced glucose utilization in incubated soleus muscle under basal conditions and prevented the palmitate-induced inhibition in insulin-stimulated conditions. However, TFA reduced the insulin response to glucose uptake and metabolism. The effects mentioned above were influenced by the FA profile modifications induced by the dietary LA levels, suggesting that lipid metabolization and incorporation into plasma membrane are important determining factors of glucose metabolism and insulin sensitivity.
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Affiliation(s)
- Ana C Fariña
- Cátedra Bromatología y Nutrición, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, C.C. 242, 3000, Santa Fe, Argentina
| | - Sandro Hirabara
- Institute of Physical Activity Sciences and Sports, Cruzeiro do Sul University, Sao Paulo, Brazil
| | - Juliana Sain
- Cátedra Bromatología y Nutrición, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, C.C. 242, 3000, Santa Fe, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina
| | - Marcela González
- Cátedra Bromatología y Nutrición, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, C.C. 242, 3000, Santa Fe, Argentina
| | - Rui Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
- Post-Graduate Program in Human Health Sciences, Biological Sciences and Health Center, Cruzeiro do Sul University, Sao Paulo, Brazil
| | - Claudio Bernal
- Cátedra Bromatología y Nutrición, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, C.C. 242, 3000, Santa Fe, Argentina.
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina.
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Mu S, Liu J, Guo W, Zhang S, Xiao X, Wang Z, Zhang J. Roux-en-Y Gastric Bypass Improves Hepatic Glucose Metabolism Involving Down-Regulation of Protein Tyrosine Phosphatase 1B in Obese Rats. Obes Facts 2017; 10:191-206. [PMID: 28564652 PMCID: PMC5644909 DOI: 10.1159/000470912] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 03/09/2017] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVE This study was initiated to investigate the effects of Roux-en-Y gastric bypass (RYGB) surgery on hepatic glucose metabolism and hepatic expression of protein tyrosine phosphatase 1B (PTP1B) in obese rats. METHODS Body weight, glucose, intraperitoneal glucose, insulin, and pyruvate tolerance tests were performed pre- and postoperatively, and plasma lipid, insulin and glucagon-like peptide 1 (GLP-1) were measured. The mRNA levels of G6Pase, Pepck, Gsk-3β and Gys-2, and the expression levels of PTP1B mRNA, protein, and other components of the insulin signaling pathway were measured by using RT-PCR and western blotting. The intracellular localization of PTP1B and hepatic glycogen deposition was also observed. RESULTS RYGB surgery-treated rats showed persistent weight loss, significantly improved glucose tolerance, pyruvate tolerance, and dyslipidemia, as well as increased insulin sensitivity, hepatic glycogen deposition and increased plasma GLP-1 in obese rats. RT-PCR analyses showed Pepck, G6Pase, and Gsk-3β mRNA to be significantly decreased, and Gys-2 mRNA to be significantly increased in liver tissue in the RYGB group (p < 0.05 vs. high-fat diet (HFD) or HFD + sham group); in addition, the expression of PTP1B were significantly decreased and insulin signaling were improved in the RYGB group (p < 0.05 vs. HFD or HFD + sham group). CONCLUSION RYGB can improve hepatic glucose metabolism and down-regulate PTP1B in obese rats. An increased circulating GLP-1 concentration may be correlated with the effects following RYGB in obese rats.
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Affiliation(s)
- Song Mu
- Department of General Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jiayu Liu
- Department of Endocrinology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Wei Guo
- Department of General Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Shuping Zhang
- Department of Endocrinology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xiaoqiu Xiao
- Laboratory of Lipid & Glucose Metabolism, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhihong Wang
- Department of Endocrinology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- *Dr. Jun Zhang and Dr. Zhihong Wang, Department of General Surgery And Department of Endocrinology, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing 400016, China, ;
| | - Jun Zhang
- Department of General Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- *Dr. Jun Zhang and Dr. Zhihong Wang, Department of General Surgery And Department of Endocrinology, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing 400016, China, ;
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Bowser SM, Moore WT, McMillan RP, Dorenkott MR, Goodrich KM, Ye L, O'Keefe SF, Hulver MW, Neilson AP. High-molecular-weight cocoa procyanidins possess enhanced insulin-enhancing and insulin mimetic activities in human primary skeletal muscle cells compared to smaller procyanidins. J Nutr Biochem 2017; 39:48-58. [PMID: 27816760 DOI: 10.1016/j.jnutbio.2016.10.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 10/01/2016] [Accepted: 10/03/2016] [Indexed: 11/23/2022]
Abstract
Dysregulation of glucose metabolism is a primary hallmark of metabolic disease (i.e., diabetes, obesity, etc.). Complementary nonpharmaceutical strategies are needed to prevent and/or ameliorate dysregulation of glucose metabolism and prevent progression from normoglycemia to prediabetes and type 2 diabetes across the lifespan. Cocoa compounds, particularly the procyanidins, have shown promise for improving insulin sensitivity and blood glucose homeostasis. However, the molecular mechanisms by which cocoa procyanidins exert these functions remain poorly understood. Furthermore, cocoa procyanidins exhibit size diversity, and evidence suggests that procyanidin bioactivity and size may be related. Here, we show that a procyanidin-rich cocoa extract elicits an antidiabetic effect by stimulating glycogen synthesis and glucose uptake, independent of insulin. Cocoa procyanidins did not appear to act via stimulation of AMPK or CaMKII activities. Additionally, in the presence of insulin, glycogen synthesis and AKT phosphorylation were affected. These mechanisms of action are most pronounced in response to oligomeric and polymeric procyanidins. These results demonstrate (1) specific mechanisms by which cocoa procyanidins improve glucose utilization in skeletal muscle and (2) that larger procyanidins appear to possess enhanced activities. These mechanistic insights suggest specific strategies and biological contexts that may be exploited to maximize the antidiabetic benefits of cocoa procyanidins.
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Jiang B, Le L, Zhai W, Wan W, Hu K, Yong P, He C, Xu L, Xiao P. Protective effects of marein on high glucose-induced glucose metabolic disorder in HepG2 cells. Phytomedicine 2016; 23:891-900. [PMID: 27387397 DOI: 10.1016/j.phymed.2016.05.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 04/06/2016] [Accepted: 05/13/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Our previous study has shown that Coreopsis tinctoria increases insulin sensitivity and regulates hepatic metabolism in high-fat diet (HFD)-induced insulin resistance rats. However, it is unclear whether or not marein, a major compound of C. tinctoria, could improve insulin resistance. Here we investigate the effect and mechanism of action of marein on improving insulin resistance in HepG2 cells. METHODS We investigated the protective effects of marein in high glucose-induced human liver carcinoma cell HepG2. In kinase inhibitor studies, genistein, LY294002, STO-609 and compound C were added to HepG2 cells 1h before the addition of marein. Transfection with siRNA was used to knock down LKB1, and 2-(N-(7-nitrobenz-2-oxa-1, 3-diazol-4-yl) amino)-2-deoxyglucose (2-NBDG), an effective tracer, was used to detect glucose uptake. RESULTS The results showed for the first time that marein significantly stimulates the phosphorylation of AMP-activated protein kinase (AMPK) and the Akt substrate of 160kDa (AS160) and enhanced the translocation of glucose transporter 1 (GLUT1) to the plasma membrane. Further study indicated that genistein (an insulin receptor tyrosine kinase inhibitor) altered the effect of marein on glucose uptake, and both LY294002 (a phosphatidylinositol 3-kinase inhibitor) and compound C (an AMP-activated protein kinase inhibitor) significantly decreased marein-stimulated 2-NBDG uptake. Additionally, marein-stimulated glucose uptake was blocked in the presence of STO-609, a CaMKK inhibitor; however, marein-stimulated AMPK phosphorylation was not blocked by LKB1 siRNA in HepG2 cells. Marein also inhibited the phosphorylation of insulin receptor substrate (IRS-1) at Ser 612, but inhibited GSK-3β phosphorylation and increased glycogen synthesis. Moreover, marein significantly decreased the expression levels of FoxO1, G6Pase and PEPCK. CONCLUSIONS Consequently, marein improved insulin resistance induced by high glucose in HepG2 cells through CaMKK/AMPK/GLUT1 to promote glucose uptake, through IRS/Akt/GSK-3β to increase glycogen synthesis, and through Akt/FoxO1 to decrease gluconeogenesis. Marein could be a promising leading compound for the development of hypoglycemic agent or developed as an adjuvant drug for diabetes mellitus.
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Affiliation(s)
- Baoping Jiang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 151 Malianwa North, Haidian District, Beijing 100193, China; Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China
| | - Liang Le
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 151 Malianwa North, Haidian District, Beijing 100193, China
| | - Wei Zhai
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 151 Malianwa North, Haidian District, Beijing 100193, China
| | - Wenting Wan
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 151 Malianwa North, Haidian District, Beijing 100193, China; Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China
| | - Keping Hu
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 151 Malianwa North, Haidian District, Beijing 100193, China
| | - Peng Yong
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 151 Malianwa North, Haidian District, Beijing 100193, China; Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China
| | - Chunnian He
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 151 Malianwa North, Haidian District, Beijing 100193, China; Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China
| | - Lijia Xu
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 151 Malianwa North, Haidian District, Beijing 100193, China; Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China
| | - Peigen Xiao
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 151 Malianwa North, Haidian District, Beijing 100193, China; Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China.
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Lin KT, Hsu SW, Lai FY, Chang TC, Shi LS, Lee SY. Rhodiola crenulata extract regulates hepatic glycogen and lipid metabolism via activation of the AMPK pathway. Altern Ther Health Med 2016; 16:127. [PMID: 27184670 PMCID: PMC4869342 DOI: 10.1186/s12906-016-1108-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 05/11/2016] [Indexed: 02/06/2023]
Abstract
Background Metabolic syndrome may lead to many complications, such as nonalcoholic fatty liver disease (NAFLD). A natural and effective therapeutic agent for patients with NAFLD is urgently needed. In a previous study, we showed that Rhodiola crenulata root extract (RCE) regulated hepatic gluconeogenesis through activation of AMPK signaling. However, the manner in which RCE regulates hepatic lipid and glycogen metabolism remains unclear. The current study was conducted to investigate the effects of RCE on hepatic glycogen and lipid metabolism, as well as the mechanisms underlying such effects. Methods Human hepatoma HepG2 cells were treated with RCE for 6 h under high glucose conditions, after which glycogen synthesis, lipogenesis, and relative gene expression were examined. In addition, lipogenesis-related genes were investigated in vivo. Results RCE significantly increased glycogen synthesis and inhibited lipogenesis, while regulating genes related to these processes, including glycogen synthase kinase 3β (GSK3β), glycogen synthase (GS), fatty acid synthase (FAS), CCAAT/enhancer-binding protein (C/EBP), and sterol regulatory element-binding protein 1c (SREBP-1c). However, the effects caused by RCE were neutralized by compound C, an AMPK antagonist. Further studies showed that expression levels of lipogenic genes decreased at the protein and mRNA levels in the rat liver. Conclusions Our results demonstrate that RCE regulates hepatic glycogen and lipid metabolism through the AMPK signaling pathway. These results suggest that RCE is a potential intervention for patients with NAFLD.
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Burgos-Ramos E, Canelles S, Frago LM, Chowen JA, Arilla-Ferreiro E, Argente J, Barrios V. Improvement in glycemia after glucose or insulin overload in leptin-infused rats is associated with insulin-related activation of hepatic glucose metabolism. Nutr Metab (Lond) 2016; 13:19. [PMID: 26937247 DOI: 10.1186/s12986-016-0079-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/25/2016] [Indexed: 11/16/2022] Open
Abstract
Background Insulin regulates glucose homeostasis through direct effects on the liver, among other organs, with leptin modulating insulin’s hepatic actions. Since central leptin may modify insulin signaling in the liver, we hypothesized that leptin infusion activates hepatic glycogen synthesis following peripheral administration of a bolus of glucose or insulin, thus regulating glycemia. Findings Oral glucose and intraperitoneal insulin tolerance tests were performed in control, intracerebroventricular leptin-treated and pair-fed rats during 14 days. An improvement in glycemia and an increase in hepatic free glucose and glycogen concentrations after glucose or insulin overload were observed in leptin-treated rats. In order to analyze whether the liver was involved in these changes, we studied activation of insulin signaling by Western blotting and multiplex bead immunoassay after leptin infusion. Our studies revealed an increase in phosphorylation of insulin receptor substrate-1 and Akt in leptin-treated rats. Examination of parameters related to glucose uptake and metabolism in the liver revealed an augment in glucose transporter 2 and a decrease in phosphoenolpyruvate carboxylase protein levels in this group. Conclusions These results indicate that central leptin increases hepatic insulin signaling, associated with increased glycogen concentrations after glucose or insulin overload, leading to an improvement in glycemia.
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Burgos-Ramos E, Canelles S, Rodríguez A, Gómez-Ambrosi J, Frago LM, Chowen JA, Frühbeck G, Argente J, Barrios V. Chronic central leptin infusion modulates the glycemia response to insulin administration in male rats through regulation of hepatic glucose metabolism. Mol Cell Endocrinol 2015; 415:157-72. [PMID: 26296906 DOI: 10.1016/j.mce.2015.08.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 08/06/2015] [Accepted: 08/09/2015] [Indexed: 10/23/2022]
Abstract
Leptin and insulin use overlapping signaling mechanisms to modify hepatic glucose metabolism, which is critical in maintaining normal glycemia. We examined the effect of an increase in central leptin and insulin on hepatic glucose metabolism and its influence on serum glucose levels. Chronic leptin infusion increased serum leptin and reduced hepatic SH-phosphotyrosine phosphatase 1, the association of suppressor of cytokine signaling 3 to the insulin receptor in liver and the rise in glycemia induced by central insulin. Leptin also decreased hepatic phosphoenolpyruvate carboxykinase levels and increased insulin's ability to phosphorylate insulin receptor substrate-1, Akt and glycogen synthase kinase on Ser9 and to stimulate glucose transporter 2 and glycogen levels. Peripheral leptin treatment reproduced some of these changes, but to a lesser extent. Our data indicate that leptin increases the hepatic response to a rise in insulin, suggesting that pharmacological manipulation of leptin targets may be of interest for controlling glycemia.
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Affiliation(s)
- Emma Burgos-Ramos
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, E-28009, Spain; IMDEA Food, CEI UAM+CSIC, Carretera de Cantoblanco 8, Madrid, E-28049, Spain
| | - Sandra Canelles
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, E-28009, Spain; Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, E-28009, Spain
| | - Amaia Rodríguez
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, E-28009, Spain; Metabolic Research Laboratory, Clínica Universidad de Navarra, IdiSNA, Pamplona, E-31008, Spain
| | - Javier Gómez-Ambrosi
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, E-28009, Spain; Metabolic Research Laboratory, Clínica Universidad de Navarra, IdiSNA, Pamplona, E-31008, Spain
| | - Laura M Frago
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, E-28009, Spain; Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, E-28009, Spain
| | - Julie A Chowen
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, E-28009, Spain; Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, E-28009, Spain
| | - Gema Frühbeck
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, E-28009, Spain; Metabolic Research Laboratory, Clínica Universidad de Navarra, IdiSNA, Pamplona, E-31008, Spain
| | - Jesús Argente
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, E-28009, Spain; Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, E-28009, Spain
| | - Vicente Barrios
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, E-28009, Spain; Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, E-28009, Spain.
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Jan M, Medh JD. ShRNA-mediated gene silencing of lipoprotein lipase improves insulin sensitivity in L6 skeletal muscle cells. Biochem Biophys Res Commun 2015; 462:33-7. [PMID: 25931001 DOI: 10.1016/j.bbrc.2015.04.098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 04/20/2015] [Indexed: 12/25/2022]
Abstract
In previous studies, we demonstrated that down-regulation of lipoprotein lipase in L6 muscle cells increased insulin-stimulated glucose uptake. In the current study, we used RNA interference technology to silence the LPL gene in L6 cells and generate a LPL-knock-down (LPL-KD) cell line. ShRNA transfected cells showed a 88% reduction in the level of LPL expression. The metabolic response to insulin was compared in wild-type (WT) and LPL-KD cells. Insulin-stimulated glycogen synthesis and glucose oxidation were respectively, 2.4-fold and 2.6-fold greater in LPL-KD cells compared to WT cells. Oxidation of oleic acid was reduced by 50% in LPL-KD cells compared to WT cells even in the absence of insulin. The contribution of LPL in regulating fuel metabolism was confirmed by adding back purified LPL to the culture media of LPL-KD cells. The presence of 10 μg/mL LPL resulted in LPL-KD cells reverting back to lower glycogen synthesis and glucose oxidation and increased fatty acid oxidation. Thus, LPL depletion appeared to mimic the action of insulin. These finding suggests an inverse correlation between muscle LPL levels and insulin-stimulated fuel homeostasis.
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Affiliation(s)
- Majib Jan
- Department of Chemistry and Biochemistry, California State University Northridge, Northridge, CA 91330-8262, USA
| | - Jheem D Medh
- Department of Chemistry and Biochemistry, California State University Northridge, Northridge, CA 91330-8262, USA.
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