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Clinically applicable GABA receptor positive allosteric modulators promote ß-cell replication. Sci Rep 2017; 7:374. [PMID: 28336918 PMCID: PMC5428733 DOI: 10.1038/s41598-017-00515-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 02/28/2017] [Indexed: 11/09/2022] Open
Abstract
A key goal of diabetes research is to develop treatments to safely promote human ß-cell replication. It has recently become appreciated that activation of γ-aminobutyric acid receptors (GABA-Rs) on ß-cells can promote their survival and replication. A number of positive allosteric modulators (PAMs) that enhance GABA’s actions on neuronal GABAA-Rs are in clinical use. Repurposing these GABAA-R PAMs to help treat diabetes is theoretically appealing because of their safety and potential to enhance the ability of GABA, secreted from ß-cells, or exogenously administered, to promote ß-cell replication and survival. Here, we show that clinically applicable GABAA-R PAMs can increase significantly INS-1 ß-cell replication, which is enhanced by exogenous GABA application. Furthermore, a GABAA-R PAM promoted human islet cell replication in vitro. This effect was abrogated by a GABAA-R antagonist. The combination of a PAM and low levels of exogenous GABA further increased human islet cell replication. These findings suggest that PAMs may potentiate the actions of GABA secreted by islet ß-cells on GABAA-Rs and provide a new class of drugs for diabetes treatment. Finally, our findings may explain a past clinical observation of a GABAA-R PAM reducing HbA1c levels in diabetic patients.
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Parente A, Vállez García D, Shoji A, Lopes Alves I, Maas B, Zijlma R, Dierckx RA, Buchpiguel CA, de Vries EF, Doorduin J. Contribution of neuroinflammation to changes in [ 11C]flumazenil binding in the rat brain: Evaluation of the inflamed pons as reference tissue. Nucl Med Biol 2017; 49:50-56. [PMID: 28364664 DOI: 10.1016/j.nucmedbio.2017.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/09/2017] [Accepted: 03/10/2017] [Indexed: 11/17/2022]
Abstract
INTRODUCTION [11C]Flumazenil is a well-known PET tracer for GABAA receptors and is mainly used as an imaging biomarker for neuronal loss. Recently, GABAA receptors on immune cells have been investigated as target for modulation of inflammation. Since neuronal loss is often accompanied by neuroinflammation, PET imaging with [11C]flumazenil is potentially affected by infiltrating immune cells. This may also compromise the validity of using the pons as reference tissue in quantitative pharmacokinetic analysis. This study aims to evaluate whether inflammatory processes in the brain can influence [11C]flumazenil uptake and affect the outcome of pharmacokinetic modeling when the pons is used as reference tissue. METHODS The herpes simplex encephalitis (HSE) rat model is known to cause neuroinflammation in the brainstem. Dynamic [11C]flumazenil PET scans of 60-min, accompanied by arterial blood sampling and metabolite analysis, were acquired at day 6-7days post-infection of male Wistar rats (HSE, n=5 and control, n=6). Additionally, the GABAA receptor was saturated by injection of unlabeled flumazenil prior to the tracer injection in 4 rats per group. PET data were analyzed by pharmacokinetic modeling. RESULTS No statistically significant differences were found in the volume of distribution (VT) or non-displaceable binding potential (BPND) between control and HSE rats in any of the brain regions. Pre-saturation with unlabeled flumazenil resulted in a statistically significant reduction in [11C]flumazenil VT in all brain regions. The BPND obtained from SRTM exhibited a good correlation to DVR - 1 values from the two-tissue compartment model, coupled with some level of underestimation. CONCLUSION Reliable quantification of [11C]flumazenil binding in rats can be obtained by pharmacokinetic analysis using the pons as a pseudo-reference tissue even in the presence of strong acute neuroinflammation.
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Affiliation(s)
- Andrea Parente
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - David Vállez García
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Alexandre Shoji
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Center of Nuclear Medicine, University of Sao Paulo, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Isadora Lopes Alves
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Bram Maas
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Rolf Zijlma
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Rudi Ajo Dierckx
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Carlos A Buchpiguel
- Center of Nuclear Medicine, University of Sao Paulo, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Erik Fj de Vries
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Janine Doorduin
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
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Ren W, Yin J, Xiao H, Chen S, Liu G, Tan B, Li N, Peng Y, Li T, Zeng B, Li W, Wei H, Yin Z, Wu G, Hardwidge PR, Yin Y. Intestinal Microbiota-Derived GABA Mediates Interleukin-17 Expression during Enterotoxigenic Escherichia coli Infection. Front Immunol 2017; 7:685. [PMID: 28138329 PMCID: PMC5237640 DOI: 10.3389/fimmu.2016.00685] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 12/22/2016] [Indexed: 12/21/2022] Open
Abstract
Intestinal microbiota has critical importance in pathogenesis of intestinal infection; however, the role of intestinal microbiota in intestinal immunity during enterotoxigenic Escherichia coli (ETEC) infection is poorly understood. The present study tested the hypothesis that the intestinal microbiota is associated with intestinal interleukin-17 (IL-17) expression in response to ETEC infection. Here, we found ETEC infection induced expression of intestinal IL-17 and dysbiosis of intestinal microbiota, increasing abundance of γ-aminobutyric acid (GABA)-producing Lactococcus lactis subsp. lactis. Antibiotics treatment in mice lowered the expression of intestinal IL-17 during ETEC infection, while GABA or L. lactis subsp. lactis administration restored the expression of intestinal IL-17. L. lactis subsp. lactis administration also promoted expression of intestinal IL-17 in germ-free mice during ETEC infection. GABA enhanced intestinal IL-17 expression in the context of ETEC infection through activating mechanistic target of rapamycin complex 1 (mTORC1)-ribosomal protein S6 kinase 1 (S6K1) signaling. GABA-mTORC1 signaling also affected intestinal IL-17 expression in response to Citrobacter rodentium infection and in drug-induced model of intestinal inflammation. These findings highlight the importance of intestinal GABA signaling in intestinal IL-17 expression during intestinal infection and indicate the potential of intestinal microbiota-GABA signaling in IL-17-associated intestinal diseases.
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Affiliation(s)
- Wenkai Ren
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Jie Yin
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Hao Xiao
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Shuai Chen
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Gang Liu
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Bie Tan
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Nengzhang Li
- Chongqing Key Laboratory of Forage and Herbivorce, College of Animal Science and Technology, Southwest University, Chongqing, China
| | - Yuanyi Peng
- Chongqing Key Laboratory of Forage and Herbivorce, College of Animal Science and Technology, Southwest University, Chongqing, China
| | - Tiejun Li
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Benhua Zeng
- Department of Laboratory Animal Science, College of Basic Medicine Science, Third Military Medical University, Chongqing, China
| | - Wenxia Li
- Department of Laboratory Animal Science, College of Basic Medicine Science, Third Military Medical University, Chongqing, China
| | - Hong Wei
- Department of Laboratory Animal Science, College of Basic Medicine Science, Third Military Medical University, Chongqing, China
| | - Zhinan Yin
- Biomedical Translational Research Institute, Jinan University, Guangzhou, China
| | - Guoyao Wu
- Department of Animal Science, Texas A&M University, College Station, TX, USA
| | - Philip R. Hardwidge
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, KS, USA
| | - Yulong Yin
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
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Praengam K, Sahasakul Y, Kupradinun P, Sakarin S, Sanitchua W, Rungsipipat A, Rattanapinyopituk K, Angkasekwinai P, Changsri K, Mhuantong W, Tangphatsornruang S, Tuntipopipat S. Brown rice and retrograded brown rice alleviate inflammatory response in dextran sulfate sodium (DSS)-induced colitis mice. Food Funct 2017; 8:4630-4643. [DOI: 10.1039/c7fo00305f] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We investigate the impact of brown rice and retrograded brown rice consumption on colonic health in dextran sulfate sodium induced colitis mice.
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Affiliation(s)
- Kemika Praengam
- Institute of Nutrition
- Mahidol University
- Nakhonpathom
- Thailand
| | | | | | | | | | - Anudep Rungsipipat
- Department of Pathology
- Faculty of Veterinary Science
- Chulalongkorn University
- Bangkok
- Thailand
| | | | - Pornpimon Angkasekwinai
- Department of Medical technology
- Faculty of Allied Health Sciences
- Thammasat University
- Pathum Thani
- Thailand
| | - Khaimuk Changsri
- Department of Medical technology
- Faculty of Allied Health Sciences
- Thammasat University
- Pathum Thani
- Thailand
| | - Wuttichai Mhuantong
- National Center for Genetic Engineering and Biotechnology
- Pathum Thani
- Thailand
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Circulating IL-27 Is Elevated in Rheumatoid Arthritis Patients. Molecules 2016; 21:molecules21111565. [PMID: 27869736 PMCID: PMC6273926 DOI: 10.3390/molecules21111565] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 11/04/2016] [Accepted: 11/14/2016] [Indexed: 02/04/2023] Open
Abstract
Cytokines are key immunoregulatory molecules that regulate T lymphocyte-mediated immune responses and inflammatory reactions. We determined whether there is aberrant expression of interleukin-27 (IL-27) in rheumatoid arthritis (RA) patients and investigated the clinical significance of these changes. IL-27 is a key cellular factor that regulates the differentiation of CD4+ T cells, which can secrete interleukin-10 (IL-10) and interleukin-17 (IL-17) in vivo. Concentrations of serum IL-27 in 67 RA patients, and 36 sex- and age-matched control subjects were measured by enzyme-linked immunosorbent assay (ELISA). Results showed that concentrations of serum IL-27 in all RA patients were significantly higher than in healthy control subjects, and there was a significant and positive correlation between serum IL-27 levels and disease activity in all RA patients. Levels of serum IL-27 in RA patients were significantly correlated with disease activity score in 28 joints (DAS28). Moreover, immunosuppressive treatment with leflunomide downregulated the levels of IL-27 in active RA patients. Therefore, the elevated production of circulating T cell inflammatory factors contributes to the pathogenesis of RA, and serum IL-27 could potentially serve as a new biomarker of RA disease activity.
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Urrutia M, Fernández S, González M, Vilches R, Rojas P, Vásquez M, Kurte M, Vega-Letter AM, Carrión F, Figueroa F, Rojas P, Irarrázabal C, Fuentealba RA. Overexpression of Glutamate Decarboxylase in Mesenchymal Stem Cells Enhances Their Immunosuppressive Properties and Increases GABA and Nitric Oxide Levels. PLoS One 2016; 11:e0163735. [PMID: 27662193 PMCID: PMC5035029 DOI: 10.1371/journal.pone.0163735] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 09/13/2016] [Indexed: 12/12/2022] Open
Abstract
The neurotransmitter GABA has been recently identified as a potent immunosuppressive agent that targets both innate and adaptive immune systems and prevents disease progression of several autoimmunity models. Mesenchymal stem cells (MSCs) are self-renewing progenitor cells that differentiate into various cell types under specific conditions, including neurons. In addition, MSC possess strong immunosuppressive capabilities. Upon cytokine priming, undifferentiated MSC suppress T-cell proliferation via cell-to-cell contact mechanisms and the secretion of soluble factors like nitric oxide, prostaglandin E2 and IDO. Although MSC and MSC-derived neuron-like cells express some GABAergic markers in vitro, the role for GABAergic signaling in MSC-mediated immunosuppression remains completely unexplored. Here, we demonstrate that pro-inflammatory cytokines selectively regulate GAD-67 expression in murine bone marrow-MSC. However, expression of GAD-65 is required for maximal GABA release by MSC. Gain of function experiments using GAD-67 and GAD-65 co-expression demonstrates that GAD increases immunosuppressive function in the absence of pro-inflammatory licensing. Moreover, GAD expression in MSC evokes an increase in both GABA and NO levels in the supernatants of co-cultured MSC with activated splenocytes. Notably, the increase in NO levels by GAD expression was not observed in cultures of isolated MSC expressing GAD, suggesting crosstalk between these two pathways in the setting of immunosuppression. These results indicate that GAD expression increases MSC-mediated immunosuppression via secretion of immunosuppressive agents. Our findings may help reconsider GABAergic activation in MSC for immunological disorders.
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Affiliation(s)
- Mariana Urrutia
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Sebastián Fernández
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Marisol González
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Rodrigo Vilches
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Pablo Rojas
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Manuel Vásquez
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Mónica Kurte
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Ana María Vega-Letter
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Flavio Carrión
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Fernando Figueroa
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Patricio Rojas
- Departamento de Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Carlos Irarrázabal
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
| | - Rodrigo A. Fuentealba
- Centro de Investigación Biomédica, Facultad de Medicina, Universidad de Los Andes, Santiago, Chile
- * E-mail:
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Feeding rumen-protected gamma-aminobutyric acid enhances the immune response and antioxidant status of heat-stressed lactating dairy cows. J Therm Biol 2016; 60:103-8. [DOI: 10.1016/j.jtherbio.2016.06.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Revised: 06/12/2016] [Accepted: 06/14/2016] [Indexed: 11/19/2022]
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58
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Chen SY, Hsu YM, Lin YJ, Huang YC, Chen CJ, Lin WD, Liao WL, Chen YT, Lin WY, Liu YH, Yang JS, Sheu JC, Tsai FJ. Current concepts regarding developmental mechanisms in diabetic retinopathy in Taiwan. Biomedicine (Taipei) 2016; 6:7. [PMID: 27154195 PMCID: PMC4859317 DOI: 10.7603/s40681-016-0007-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 03/31/2016] [Indexed: 12/15/2022] Open
Abstract
Diabetic retinopathy (DR) is one of the most feared complications of diabetes and is a leading cause of acquired blindness in working adults. The prevalence of undiagnosed diabetes in Taiwan is about 4%, and the annual incidence of T2D (Type 2 Diabetes) in Taiwan is 1.8% following the 1985 WHO criteria. Multiple mechanisms have been shown in T2DR with some signaling pathways, including the polyol pathway, PKC pathway, AGEs pathway, and MAPK pathway. However, the cause of vision loss in diabetic retinopathy is complex and remains incompletely understood. Herein, we try to fully understand the new concepts regarding hyperglycemia-induced biochemical pathways contributing to DR pathophysiology. Our work may be able to provide new strategies for the prevention and treatment of diabetic vascular complications.
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Affiliation(s)
- Shih-Yin Chen
- Genetics Center, Department of Medical Research, China Medical University Hospital, No. 2 Yuh Der Road, 404, Taichung, Taiwan
- School of Chinese Medicine, China Medical University, 404, Taichung, Taiwan
| | - Yuan-Man Hsu
- Department of Biological Science and Technology, China Medical University, 404, Taichung, Taiwan
| | - Ying-Ju Lin
- Genetics Center, Department of Medical Research, China Medical University Hospital, No. 2 Yuh Der Road, 404, Taichung, Taiwan
- School of Chinese Medicine, China Medical University, 404, Taichung, Taiwan
| | - Yu-Chuen Huang
- Genetics Center, Department of Medical Research, China Medical University Hospital, No. 2 Yuh Der Road, 404, Taichung, Taiwan
- School of Chinese Medicine, China Medical University, 404, Taichung, Taiwan
| | - Chao-Jung Chen
- Genetics Center, Department of Medical Research, China Medical University Hospital, No. 2 Yuh Der Road, 404, Taichung, Taiwan
- School of Chinese Medicine, China Medical University, 404, Taichung, Taiwan
| | - Wei-De Lin
- Genetics Center, Department of Medical Research, China Medical University Hospital, No. 2 Yuh Der Road, 404, Taichung, Taiwan
- School of Chinese Medicine, China Medical University, 404, Taichung, Taiwan
| | - Wen-Lin Liao
- Genetics Center, Department of Medical Research, China Medical University Hospital, No. 2 Yuh Der Road, 404, Taichung, Taiwan
- School of Chinese Medicine, China Medical University, 404, Taichung, Taiwan
| | - Yng-Tay Chen
- Genetics Center, Department of Medical Research, China Medical University Hospital, No. 2 Yuh Der Road, 404, Taichung, Taiwan
- School of Chinese Medicine, China Medical University, 404, Taichung, Taiwan
| | - Wei-Yong Lin
- Genetics Center, Department of Medical Research, China Medical University Hospital, No. 2 Yuh Der Road, 404, Taichung, Taiwan
- School of Chinese Medicine, China Medical University, 404, Taichung, Taiwan
| | - Yu-Huei Liu
- Genetics Center, Department of Medical Research, China Medical University Hospital, No. 2 Yuh Der Road, 404, Taichung, Taiwan
- School of Chinese Medicine, China Medical University, 404, Taichung, Taiwan
| | - Jai-Sing Yang
- Genetics Center, Department of Medical Research, China Medical University Hospital, No. 2 Yuh Der Road, 404, Taichung, Taiwan
| | - Jinn-Chyuan Sheu
- Institute of Biomedical Sciences, National Sun Yat-sen University, 804, Kaohsiung, Taiwan
| | - Fuu-Jen Tsai
- Genetics Center, Department of Medical Research, China Medical University Hospital, No. 2 Yuh Der Road, 404, Taichung, Taiwan.
- School of Chinese Medicine, China Medical University, 404, Taichung, Taiwan.
- Department of Medical Genetics, China Medical University Hospital, 404, Taichung, Taiwan.
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Chang VHS, Chiu TH, Fu SC. In vitro anti-inflammatory properties of fermented pepino (Solanum muricatum) milk by γ-aminobutyric acid-producing Lactobacillus brevis and an in vivo animal model for evaluating its effects on hypertension. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2016; 96:192-198. [PMID: 25582456 DOI: 10.1002/jsfa.7081] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 12/11/2014] [Accepted: 01/06/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND The objectives of this study were to determine the in vitro anti-inflammatory and in vivo antihypertensive effects of fermented pepino (Solanum muricatum) milk by Lactobacillus brevis with the goal of developing functional healthy products. The inflammatory factors of fermented pepino milk with L. brevis were assessed in RAW 264.7 macrophages, including nitric oxide (NO) production. Inflammatory factor genes of cyclooxygenase (COX)-1 and -2, and tumor necrosis factor (TNF)-α were also assayed by a reverse transcription-polymerase chain reaction (RT-PCR). RESULTS Results showed that fermented PE inhibited NO production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells with 150 mg mL(-1) fermented PE completely blocking LPS-induced NO production. The mRNA expressions of COX-1, COX-2, and iNOS were attenuated by treatment with higher concentrations of fermented PE (150 mg/ml). Cells treated with fermented pepino extract (PE) (100 ng mL(-1)) exhibited strikingly decreased LPS-induced expression of TNF-α mRNA. During the feeding trial, rats treated with 10% fermented pepino milk (100 µg 2.5 mL(-1)) and 100% fermented pepino milk (1000 µg 2.5 mL(-1)) exhibited significant decreases in the systolic blood pressure. CONCLUSION Our results showed that fermented pepino milk has wide potential applications for development as a health food.
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Affiliation(s)
- Vincent Hung-Shu Chang
- Program for Translation Medicine, College of Medical Science and Technology, TMU, Taipei, Taiwan
| | - Tsai-Hsin Chiu
- Department of Food Science, National PengHu University of Science and Technology, Penghu County, Taiwan
| | - Szu-Chieh Fu
- Department of Food Science, National PengHu University of Science and Technology, Penghu County, Taiwan
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Li J, Zhang Z, Liu X, Wang Y, Mao F, Mao J, Lu X, Jiang D, Wan Y, Lv JY, Cao G, Zhang J, Zhao N, Atkinson M, Greiner DL, Prud'homme GJ, Jiao Z, Li Y, Wang Q. Study of GABA in Healthy Volunteers: Pharmacokinetics and Pharmacodynamics. Front Pharmacol 2015; 6:260. [PMID: 26617516 PMCID: PMC4639630 DOI: 10.3389/fphar.2015.00260] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 10/20/2015] [Indexed: 01/13/2023] Open
Abstract
Preclinical studies show that GABA exerts anti-diabetic effects in rodent models of type 1 diabetes. Because little is known about its absorption and effects in humans, we investigated the pharmacokinetics and pharmacodynamics of GABA in healthy volunteers. Twelve subjects were subjected to an open-labeled, three-period trial involving sequential oral administration of placebo, 2 g GABA once, and 2 g GABA three times/day for 7 days, with a 7-day washout between each period. GABA was rapidly absorbed (Tmax: 0.5 ~ 1 h) with the half-life (t1/2) of 5 h. No accumulation was observed after repeated oral GABA administration for 7 days. Remarkably, GABA significantly increased circulating insulin levels in the subjects under either fasting (1.6-fold, single dose; 2.0-fold, repeated dose; p < 0.01) or fed conditions (1.4-fold, single dose; 1.6-fold, repeated dose; p < 0.01). GABA also increased glucagon levels only under fasting conditions (1.3-fold, single dose, p < 0.05; 1.5-fold, repeated dose, p < 0.01). However, there were no significant differences in the insulin-to-glucagon ratio and no significant change in glucose levels in these healthy subjects during the study period. Importantly, GABA significantly decreased glycated albumin levels in the repeated dosing period. Subjects with repeated dosing showed an elevated incidence of minor adverse events in comparison to placebo or the single dosing period, most notably transient discomforts such as dizziness and sore throat. However, there were no serious adverse events observed throughout the study. Our data show that GABA is rapidly absorbed and tolerated in human beings; its endocrine effects, exemplified by increasing islet hormonal secretion, suggest potential therapeutic benefits for diabetes.
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Affiliation(s)
- Junfeng Li
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University Shanghai, China
| | - Zhaoyun Zhang
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University Shanghai, China
| | - Xiaoxia Liu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University Shanghai, China
| | - Yi Wang
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University Shanghai, China
| | - Fei Mao
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University Shanghai, China
| | - Junjun Mao
- Department of Pharmacy, Huashan Hospital, Fudan University Shanghai, China
| | - Xiaolan Lu
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University Shanghai, China
| | - Dongdong Jiang
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University Shanghai, China
| | - Yun Wan
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University Shanghai, China
| | - Jia-Ying Lv
- Department of Biostatistics, School of Public Health, Fudan University Shanghai, China
| | - Guoying Cao
- Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Institute of Antibiotics, Huashan Hospital, Fudan University Shanghai, China
| | - Jing Zhang
- Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Institute of Antibiotics, Huashan Hospital, Fudan University Shanghai, China
| | - Naiqing Zhao
- Department of Biostatistics, School of Public Health, Fudan University Shanghai, China
| | - Mark Atkinson
- Department of Pathology, College of Medicine, University of Florida Gainesville, FL, USA
| | - Dale L Greiner
- Department of Molecular Medicine, University of Massachusetts Medical School Worcester, MA, USA
| | - Gerald J Prud'homme
- Department of Laboratory Medicine and Pathobiology, Keenan Research Centre for Biomedical Science of St. Michael's Hospital, University of Toronto Toronto, ON, Canada
| | - Zheng Jiao
- Department of Pharmacy, Huashan Hospital, Fudan University Shanghai, China
| | - Yiming Li
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University Shanghai, China
| | - Qinghua Wang
- Department of Endocrinology and Metabolism, Huashan Hospital, Fudan University Shanghai, China ; Division of Endocrinology and Metabolism, The Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital Toronto, ON, Canada ; Department of Physiology and Medicine, University of Toronto ON, Canada
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Prud'homme GJ, Glinka Y, Wang Q. Immunological GABAergic interactions and therapeutic applications in autoimmune diseases. Autoimmun Rev 2015; 14:1048-56. [DOI: 10.1016/j.autrev.2015.07.011] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 07/17/2015] [Indexed: 12/20/2022]
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Huang S, Mao J, Wei B, Pei G. The anti-spasticity drug baclofen alleviates collagen-induced arthritis and regulates dendritic cells. J Cell Physiol 2015; 230:1438-47. [PMID: 25556830 DOI: 10.1002/jcp.24884] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 12/05/2014] [Indexed: 12/27/2022]
Abstract
Baclofen is used clinically as a drug that treats spasticity, which is a syndrome characterized by excessive contraction of the muscles and hyperflexia in the central nervous system (CNS), by activating GABA(B) receptors (GABA(B)Rs). Baclofen was recently reported to desensitize chemokine receptors and to suppress inflammation through the activation of GABA(B)Rs. GABA(B)Rs are expressed in various immune cells, but the functions of these receptors in autoimmune diseases remain largely unknown. In this study, we investigated the effects of baclofen in murine collagen-induced arthritis (CIA). Oral administration of baclofen alleviated the clinical development of CIA, with a reduced number of IL-17-producing T helper 17 (T(H)17) cells. In addition, baclofen treatment suppressed dendritic cell (DC)-primed T(H)17 cell differentiation by reducing the production of IL-6 by DCs in vitro. Furthermore, the pharmacological and genetic blockade of GABA(B)Rs in DCs weakened the effects of baclofen, indicating that GABA(B)Rs are the molecular targets of baclofen on DCs. Thus, our findings revealed a potential role for baclofen in the treatment of CIA, as well as a previously unknown signaling pathway that regulates DC function.
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Affiliation(s)
- Shichao Huang
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Graduate School of the Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, P. R. China
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Mabunga DFN, Gonzales ELT, Kim HJ, Choung SY. Treatment of GABA from Fermented Rice Germ Ameliorates Caffeine-Induced Sleep Disturbance in Mice. Biomol Ther (Seoul) 2015; 23:268-74. [PMID: 25995826 PMCID: PMC4428720 DOI: 10.4062/biomolther.2015.022] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 03/04/2015] [Accepted: 03/10/2015] [Indexed: 01/25/2023] Open
Abstract
γ-Aminobutyric acid (GABA), a major inhibitory neurotransmitter in the mammalian central nervous system, is involved in sleep physiology. Caffeine is widely used psychoactive substance known to induce wakefulness and insomnia to its consumers. This study was performed to examine whether GABA extracts from fermented rice germ ameliorates caffeine-induced sleep disturbance in mice, without affecting spontaneous locomotor activity and motor coordination. Indeed, caffeine (10 mg/kg, i.p.) delayed sleep onset and reduced sleep duration of mice. Conversely, rice germ ferment extracts-GABA treatment (10, 30, or 100 mg/kg, p.o.), especially at 100 mg/kg, normalized the sleep disturbance induced by caffeine. In locomotor tests, rice germ ferment extracts-GABA slightly but not significantly reduced the caffeine-induced increase in locomotor activity without affecting motor coordination. Additionally, rice germ ferment extracts-GABA per se did not affect the spontaneous locomotor activity and motor coordination of mice. In conclusion, rice germ ferment extracts-GABA supplementation can counter the sleep disturbance induced by caffeine, without affecting the general locomotor activities of mice.
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Affiliation(s)
- Darine Froy N Mabunga
- Department of Neuroscience, School of Medicine, and Neuroscience Research Center, SMART-IABS and KU Open Innovation Center, Konkuk University, Seoul 143-701
| | - Edson Luck T Gonzales
- Department of Neuroscience, School of Medicine, and Neuroscience Research Center, SMART-IABS and KU Open Innovation Center, Konkuk University, Seoul 143-701
| | - Hee Jin Kim
- Uimyung Research Institute for Neuroscience, Department of Pharmacy, Sahmyook University, Seoul 139-742
| | - Se Young Choung
- Department of Preventive Pharmacy and Toxicology, College of Pharmacy, Kyung Hee University, Seoul 130-701, Republic of Korea
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64
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Jin S, Merchant ML, Ritzenthaler JD, McLeish KR, Lederer ED, Torres-Gonzalez E, Fraig M, Barati MT, Lentsch AB, Roman J, Klein JB, Rane MJ. Baclofen, a GABABR agonist, ameliorates immune-complex mediated acute lung injury by modulating pro-inflammatory mediators. PLoS One 2015; 10:e0121637. [PMID: 25848767 PMCID: PMC4388838 DOI: 10.1371/journal.pone.0121637] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 02/12/2015] [Indexed: 11/22/2022] Open
Abstract
Immune-complexes play an important role in the inflammatory diseases of the lung. Neutrophil activation mediates immune-complex (IC) deposition-induced acute lung injury (ALI). Components of gamma amino butyric acid (GABA) signaling, including GABA B receptor 2 (GABABR2), GAD65/67 and the GABA transporter, are present in the lungs and in the neutrophils. However, the role of pulmonary GABABR activation in the context of neutrophil-mediated ALI has not been determined. Thus, the objective of the current study was to determine whether administration of a GABABR agonist, baclofen would ameliorate or exacerbate ALI. We hypothesized that baclofen would regulate IC-induced ALI by preserving pulmonary GABABR expression. Rats were subjected to sham injury or IC-induced ALI and two hours later rats were treated intratracheally with saline or 1 mg/kg baclofen for 2 additional hours and sacrificed. ALI was assessed by vascular leakage, histology, TUNEL, and lung caspase-3 cleavage. ALI increased total protein, tumor necrosis factor α (TNF-α and interleukin-1 receptor associated protein (IL-1R AcP), in the bronchoalveolar lavage fluid (BALF). Moreover, ALI decreased lung GABABR2 expression, increased phospho-p38 MAPK, promoted IκB degradation and increased neutrophil influx in the lung. Administration of baclofen, after initiation of ALI, restored GABABR expression, which was inhibited in the presence of a GABABR antagonist, CGP52432. Baclofen administration activated pulmonary phospho-ERK and inhibited p38 MAPK phosphorylation and IκB degradation. Additionally, baclofen significantly inhibited pro-inflammatory TNF-α and IL-1βAcP release and promoted BAL neutrophil apoptosis. Protective effects of baclofen treatment on ALI were possibly mediated by inhibition of TNF-α- and IL-1β-mediated inflammatory signaling. Interestingly, GABABR2 expression was regulated in the type II pneumocytes in lung tissue sections from lung injured patients, further suggesting a physiological role for GABABR2 in the repair process of lung damage. GABABR2 agonists may play a potential therapeutic role in ALI.
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Affiliation(s)
- Shunying Jin
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Michael L. Merchant
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Jeffrey D. Ritzenthaler
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Kenneth R. McLeish
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, Kentucky, United States of America
- Robley Rex VA Medical Center, Zorn Avenue, Louisville, Kentucky, United States of America
| | - Eleanor D. Lederer
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Robley Rex VA Medical Center, Zorn Avenue, Louisville, Kentucky, United States of America
- Department of Physiology, University of Louisville, Louisville, Kentucky, United States of America
| | - Edilson Torres-Gonzalez
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Mostafa Fraig
- Department of Pathology, University of Louisville, Louisville, Kentucky, United States of America
| | - Michelle T. Barati
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Alex B. Lentsch
- Department of Surgery, University of Cincinnati, Cincinnati, OH, United States of America
| | - Jesse Roman
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Robley Rex VA Medical Center, Zorn Avenue, Louisville, Kentucky, United States of America
| | - Jon B. Klein
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, Kentucky, United States of America
- Robley Rex VA Medical Center, Zorn Avenue, Louisville, Kentucky, United States of America
| | - Madhavi J. Rane
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Department of Biochemistry and Molecular Biology, University of Louisville, Louisville, Kentucky, United States of America
- * E-mail:
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Auteri M, Zizzo MG, Serio R. GABA and GABA receptors in the gastrointestinal tract: from motility to inflammation. Pharmacol Res 2015; 93:11-21. [PMID: 25526825 DOI: 10.1016/j.phrs.2014.12.001] [Citation(s) in RCA: 164] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 11/28/2014] [Accepted: 12/01/2014] [Indexed: 12/16/2022]
Abstract
Although an extensive body of literature confirmed γ-aminobutyric acid (GABA) as mediator within the enteric nervous system (ENS) controlling gastrointestinal (GI) function, the true significance of GABAergic signalling in the gut is still a matter of debate. GABAergic cells in the bowel include neuronal and endocrine-like cells, suggesting GABA as modulator of both motor and secretory GI activity. GABA effects in the GI tract depend on the activation of ionotropic GABAA and GABAC receptors and metabotropic GABAB receptors, resulting in a potential noteworthy regulation of both the excitatory and inhibitory signalling in the ENS. However, the preservation of GABAergic signalling in the gut could not be limited to the maintenance of physiologic intestinal activity. Indeed, a series of interesting studies have suggested a potential key role of GABA in the promising field of neuroimmune interaction, being involved in the modulation of immune cell activity associated with different systemic and enteric inflammatory conditions. Given the urgency of novel therapeutic strategies against chronic immunity-related pathologies, i.e. multiple sclerosis and Inflammatory Bowel Disease, an in-depth comprehension of the enteric GABAergic system in health and disease could provide the basis for new clinical application of nerve-driven immunity. Hence, in the attempt to drive novel researches addressing both the physiological and pathological importance of the GABAergic signalling in the gut, we summarized current evidence on GABA and GABA receptor function in the different parts of the GI tract, with particular focus on the potential involvement in the modulation of GI motility and inflammation.
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Affiliation(s)
- Michelangelo Auteri
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Laboratorio di Fisiologia generale, Università di Palermo, Viale delle Scienze, I-90128 Palermo, Italy
| | - Maria Grazia Zizzo
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Laboratorio di Fisiologia generale, Università di Palermo, Viale delle Scienze, I-90128 Palermo, Italy
| | - Rosa Serio
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Laboratorio di Fisiologia generale, Università di Palermo, Viale delle Scienze, I-90128 Palermo, Italy.
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66
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Tuntipopipat S, Muangnoi C, Thiyajai P, Srichamnong W, Charoenkiatkul S, Praengam K. A bioaccessible fraction of parboiled germinated brown rice exhibits a higher anti-inflammatory activity than that of brown rice. Food Funct 2015; 6:1480-8. [DOI: 10.1039/c4fo01194e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Parboiled germinated brown rice (PGBR) has been suggested as a functional food because it is relatively rich in a number of nutrients and health promoting compounds.
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Affiliation(s)
| | | | - Parunya Thiyajai
- Institute of Nutrition
- Mahidol University
- Nakhonpathom 73170
- Thailand
| | | | | | - Kemika Praengam
- Institute of Nutrition
- Mahidol University
- Nakhonpathom 73170
- Thailand
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67
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Abstract
Ion channels and transporters mediate the transport of charged ions across hydrophobic lipid membranes. In immune cells, divalent cations such as calcium, magnesium, and zinc have important roles as second messengers to regulate intracellular signaling pathways. By contrast, monovalent cations such as sodium and potassium mainly regulate the membrane potential, which indirectly controls the influx of calcium and immune cell signaling. Studies investigating human patients with mutations in ion channels and transporters, analysis of gene-targeted mice, or pharmacological experiments with ion channel inhibitors have revealed important roles of ionic signals in lymphocyte development and in innate and adaptive immune responses. We here review the mechanisms underlying the function of ion channels and transporters in lymphocytes and innate immune cells and discuss their roles in lymphocyte development, adaptive and innate immune responses, and autoimmunity, as well as recent efforts to develop pharmacological inhibitors of ion channels for immunomodulatory therapy.
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Affiliation(s)
- Stefan Feske
- Department of Pathology, New York University School of Medicine, New York, NY 10016
| | - Heike Wulff
- Department of Pharmacology, School of Medicine, University of California, Davis, California 95616
| | - Edward Y. Skolnik
- Division of Nephrology, New York University School of Medicine, New York, NY 10016
- Department of Molecular Pathogenesis, New York University School of Medicine, New York, NY 10016
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016
- The Helen L. and Martin S. Kimmel Center for Biology and Medicine at the Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York, NY 10016
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Tian J, Dang H, Nguyen AV, Chen Z, Kaufman DL. Combined therapy with GABA and proinsulin/alum acts synergistically to restore long-term normoglycemia by modulating T-cell autoimmunity and promoting β-cell replication in newly diabetic NOD mice. Diabetes 2014; 63:3128-34. [PMID: 25146474 PMCID: PMC4141368 DOI: 10.2337/db13-1385] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Antigen-based therapies (ABTs) fail to restore normoglycemia in newly diabetic NOD mice, perhaps because too few β-cells remain by the time that ABT-induced regulatory responses arise and spread. We hypothesized that combining a fast-acting anti-inflammatory agent with an ABT could limit pathogenic responses while ABT-induced regulatory responses arose and spread. γ-Aminobutyric acid (GABA) administration can inhibit inflammation, enhance regulatory T-cell (Treg) responses, and promote β-cell replication in mice. We examined the effect of combining a prototypic ABT, proinsulin/alum, with GABA treatment in newly diabetic NOD mice. Proinsulin/alum monotherapy failed to correct hyperglycemia, while GABA monotherapy restored normoglycemia for a short period. Combined treatment restored normoglycemia in the long term with apparent permanent remission in some mice. Proinsulin/alum monotherapy induced interleukin (IL)-4- and IL-10-secreting T-cell responses that spread to other β-cell autoantigens. GABA monotherapy induced moderate IL-10 (but not IL-4) responses to β-cell autoantigens. Combined treatment synergistically reduced spontaneous type 1 T-helper cell responses to autoantigens, ABT-induced IL-4 and humoral responses, and insulitis, but enhanced IL-10 and Treg responses and promoted β-cell replication in the islets. Thus, combining ABT with GABA can inhibit pathogenic T-cell responses, induce Treg responses, promote β-cell replication, and effectively restore normoglycemia in newly diabetic NOD mice. Since these treatments appear safe for humans, they hold promise for type 1 diabetes intervention.
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Affiliation(s)
- Jide Tian
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA
| | - Hoa Dang
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA
| | - An Viet Nguyen
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA
| | - Zheying Chen
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA
| | - Daniel L Kaufman
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA
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69
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Anti-inflammatory and antinociceptive activities of untreated, germinated, and fermented mung bean aqueous extract. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 2014:350507. [PMID: 25045389 PMCID: PMC4089844 DOI: 10.1155/2014/350507] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 05/30/2014] [Accepted: 06/05/2014] [Indexed: 12/28/2022]
Abstract
Evaluation of anti-inflammatory and antinociceptive activities of untreated mung bean (MB), germinated mung bean (GMB), and fermented mung bean (FMB) was performed on both in vitro (inhibition of inflammatory mediator, nitric oxide(NO)) and in vivo (inhibition of ear oedema and reduction of response to pain stimulus) studies. Results showed that both GMB and FMB aqueous extract exhibited potent anti-inflammatory and antinociceptive activities in a dose-dependent manner. In vitro results showed that GMB and FMB were potent inflammatory mediator (NO) inhibitors at both 2.5 and 5 mg/mL. Further in vivo studies showed that GMB and FMB aqueous extract at 1000 mg/kg can significantly reduce ear oedema in mice caused by arachidonic acid. Besides, both 200 mg/kg and 1000 mg/kg concentrations of GMB and FMB were found to exhibit potent antinociceptive effects towards hotplate induced pain. With these, it can be concluded that GMB and FMB aqueous extract exhibited potential anti-inflammatory and antinociceptive effects.
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70
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Paul AM, Branton WG, Walsh JG, Polyak MJ, Lu JQ, Baker GB, Power C. GABA transport and neuroinflammation are coupled in multiple sclerosis: regulation of the GABA transporter-2 by ganaxolone. Neuroscience 2014; 273:24-38. [PMID: 24814730 DOI: 10.1016/j.neuroscience.2014.04.037] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 04/15/2014] [Accepted: 04/17/2014] [Indexed: 10/25/2022]
Abstract
Interactions between neurotransmitters and the immune system represent new prospects for understanding neuroinflammation and associated neurological disease. GABA is the chief inhibitory neurotransmitter but its actions on immune pathways in the brain are unclear. In the present study, we investigated GABAergic transport in conjunction with neuroinflammation in models of multiple sclerosis (MS). Protein and mRNA levels of γ-amino butyric acid transporter 2 (GAT-2) were examined in cerebral white matter from MS and control (Non-MS) patients, in cultured human macrophages, microglia and astrocytes, and in spinal cords from mice with and without experimental autoimmune encephalomyelitis (EAE) using western blotting, immunocytochemistry and quantitative real-time polymerase chain reaction (qRT-PCR). GABA levels were measured by HPLC. The GAT-2's expression was increased in MS patients' (n=6) white matter, particularly in macrophage lineage cells, compared to Non-MS patients (n=6) (p<0.05). Interferon-γ (IFN-γ) stimulation of human macrophage lineage cells induced GAT-2 expression and reduced extracellular GABA levels (p<0.05) but soluble GABA treatment suppressed HLA-DRα, GAT-2 and XBP-1/s expression in stimulated macrophage lineage cells (p<0.05). Similarly, the synthetic allopregnanolone analog, ganaxolone (GNX), repressed GAT-2, JAK-1 and STAT-1 expression in activated macrophage lineage cells (p<0.05). In vivo GNX treatment reduced Gat-2, Cd3ε, MhcII, and Xbp-1/s expression in spinal cords following EAE induction (p<0.05), which was correlated with improved neurobehavioral outcomes and reduced neuroinflammation, demyelination and axonal injury. These findings highlight altered GABAergic transport through GAT-2 induction during neuroinflammation. GABA transport and neuroinflammation are closely coupled but regulated by GNX, pointing to GABAergic pathways as therapeutic targets in neuroinflammatory diseases.
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Affiliation(s)
- A M Paul
- Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - W G Branton
- Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - J G Walsh
- Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - M J Polyak
- Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - J-Q Lu
- Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, AB, Canada
| | - G B Baker
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
| | - C Power
- Department of Medicine, University of Alberta, Edmonton, AB, Canada; Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, AB, Canada.
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71
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GABA protects human islet cells against the deleterious effects of immunosuppressive drugs and exerts immunoinhibitory effects alone. Transplantation 2013; 96:616-23. [PMID: 23851932 DOI: 10.1097/tp.0b013e31829c24be] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND We recently found that γ-aminobutyric acid (GABA) protects mouse islet β cells. It prevented autoimmune type 1 diabetes in mice, induced islet β-cell regeneration, and exerted immunoinhibitory effects. However, it is not known whether GABA would be equally active on human islet and immune cells. METHODS In vitro culture of human islets and immune cells with or without GABA and immunosuppressive drugs. In vitro analysis of apoptosis, proliferation, nuclear factor (NF)-κB activation, calcium signaling, and insulin secretion. RESULTS GABA reduced human islet cell apoptosis in culture, such that the yield of live cells was approximately tripled after 1 week, and it stimulated insulin secretion. It protected against the deleterious effects of rapamycin, tacrolimus, and mycophenolate mofetil. In human immune cells, GABA had inhibitory effects similar to mouse cells, such as suppressed anti-CD3-stimulated T-cell proliferation, in a GABA type A receptor-dependent fashion. The immunosuppressive mechanisms have been unclear, but we found that GABA blocked calcium influx, which is a key activation signal. GABA also suppressed NF-κB activation in both human islet cells and immune cells. We found that it could be combined with rapamycin to increase its suppressive effects. CONCLUSIONS GABA improved human islet cell survival and had suppressive effects on human immune cells. It inhibited canonical NF-κB activation in both islet and immune cells. This is important because activation of this pathway is detrimental to islet cells and likely promotes damaging autoimmunity and alloreactivity against transplanted islets. These findings suggest that GABA might find applications in clinical islet transplantation.
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Tian J, Dang H, Chen Z, Guan A, Jin Y, Atkinson MA, Kaufman DL. γ-Aminobutyric acid regulates both the survival and replication of human β-cells. Diabetes 2013; 62:3760-5. [PMID: 23995958 PMCID: PMC3806626 DOI: 10.2337/db13-0931] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
γ-Aminobutyric acid (GABA) has been shown to inhibit apoptosis of rodent β-cells in vitro. In this study, we show that activation of GABAA receptors (GABAA-Rs) or GABAB-Rs significantly inhibits oxidative stress-related β-cell apoptosis and preserves pancreatic β-cells in streptozotocin-rendered hyperglycemic mice. Moreover, treatment with GABA, or a GABAA-R- or GABAB-R-specific agonist, inhibited human β-cell apoptosis following islet transplantation into NOD/scid mice. Accordingly, activation of GABAA-Rs and/or GABAB-Rs may be a useful adjunct therapy for human islet transplantation. GABA-R agonists also promoted β-cell replication in hyperglycemic mice. While a number of agents can promote rodent β-cell replication, most fail to provide similar activities with human β-cells. In this study, we show that GABA administration promotes β-cell replication and functional recovery in human islets following implantation into NOD/scid mice. Human β-cell replication was induced by both GABAA-R and GABAB-R activation. Hence, GABA regulates both the survival and replication of human β-cells. These actions, together with the anti-inflammatory properties of GABA, suggest that modulation of peripheral GABA-Rs may represent a promising new therapeutic strategy for improving β-cell survival following human islet transplantation and increasing β-cells in patients with diabetes.
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Affiliation(s)
- Jide Tian
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, California
- Corresponding author: Daniel L. Kaufman, , or Jide Tian,
| | - Hoa Dang
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, California
| | - Zheying Chen
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, California
| | - Alice Guan
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, California
| | - Yingli Jin
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, California
| | - Mark A. Atkinson
- Departments of Pathology and Pediatrics, University of Florida, Gainesville, Florida
| | - Daniel L. Kaufman
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, California
- Corresponding author: Daniel L. Kaufman, , or Jide Tian,
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Yang Y, Luo H, Cheng LX, Liu K. Inhibitory role for GABA in atherosclerosis. Med Hypotheses 2013; 81:803-4. [PMID: 24075593 DOI: 10.1016/j.mehy.2013.08.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 08/14/2013] [Accepted: 08/28/2013] [Indexed: 11/17/2022]
Abstract
γ-Aminobutyric acid (GABA), the classical inhibitory neurotransmitter in the nervous system, has a parallel inhibitory role in the immune system. It affects a variety of functional properties of the immune cells like monocyte migration, macrophage cholesterol efflux, regulatory T cell proliferation and inflammatory cytokine secretion. All of these are the main pathologic processes of atherosclerosis, a chronic inflammatory disease involving both innate and adaptive immune responses in the artery wall. Moreover, GABA has neuroprotective effects in brain ischemic injury, which is one of the serious complications of atherosclerosis. Therefore, we hypothesize GABA may be a prospect immune cell targeting therapy in atherosclerosis.
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Affiliation(s)
- Ying Yang
- Department of Cardiology, Union Hospital, Huazhong University of Science and Technology, Wuhan 430022, China
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74
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Abstract
The mechanisms leading to the onset and perpetuation of systemic and tissue-specific autoimmune diseases are complex, and numerous hypotheses have been proposed or confirmed over the past 12 months. It is particularly of note that the number of articles published during 2011 in the major immunology and autoimmunity journals increased by 3 % compared to the previous year. The present article is dedicated to a brief review of the reported data and, albeit not comprehensive of all articles, is aimed at identifying common and future themes. First, clinical researchers were particularly dedicated to defining refractory forms of diseases and to discuss the use and switch of therapeutic monoclonal antibodies in everyday practice. Second, following the plethora of genome-wide association studies reported in most multifactorial diseases, it became clear that genomics cannot fully explain the individual susceptibility and additional environmental or epigenetic factors are necessary. Both these components were widely investigated, both in organ-specific (i.e., type 1 diabetes) and systemic (i.e., systemic lupus erythematosus) diseases. Third, a large number of 2011 works published in the autoimmunity area are dedicated to dissect pathogenetic mechanisms of tolerance breakdown in general or in specific conditions. While our understanding of T regulatory and Th17 cells has significantly increased in 2011, it is of note that most of the proposed lines of evidence identify potential targets for future treatments and should not be overlooked.
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75
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Cao J, Zou L, Luo P, Chen P, Zhang L. Increased production of circulating soluble co-stimulatory molecules CTLA-4, CD28 and CD80 in patients with rheumatoid arthritis. Int Immunopharmacol 2012; 14:585-92. [PMID: 22917707 DOI: 10.1016/j.intimp.2012.08.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Revised: 07/30/2012] [Accepted: 08/05/2012] [Indexed: 01/29/2023]
Abstract
Co-stimulatory molecules are key immunoregulatory mediators in regulating T lymphocyte-mediated immune responses and inflammatory reactions. Here we investigated whether there is altered expression and the clinical significance of circulating soluble co-stimulatory molecules in rheumatoid arthritis (RA) patients. Serum concentrations of sCTLA-4, sCD28, sCD80 and sCD86 in 56 RA patients, and 32 sex- and age-matched control subjects were measured by enzyme-linked immunosorbent assay (ELISA). Results showed that serum sCTLA-4, sCD28, and CD80 but not CD86 concentrations in all RA patients were significantly higher than concentrations in healthy control subjects. And there was significant and positive correlation between serum CTLA-4 and sCD28, sCD28 and sCD80, or sCTLA-4 and sCD80 in all RA patients. Serum sCTLA-4 concentration in all RA patients correlated significantly with disease activity score in 28 joints (DAS28). Moreover, immunosuppressant treatment with leflunomide could downregulate the increased levels of sCTLA-4, sCD28, and CD80 in RA patients. Therefore, the elevated production of circulating soluble T-cell co-stimulatory molecules should contribute to the pathogenesis of RA, and serum sCTLA-4 could potentially serve as a new marker of RA disease activity.
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Affiliation(s)
- Ju Cao
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
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76
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Feske S, Skolnik EY, Prakriya M. Ion channels and transporters in lymphocyte function and immunity. Nat Rev Immunol 2012; 12:532-47. [PMID: 22699833 DOI: 10.1038/nri3233] [Citation(s) in RCA: 335] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Lymphocyte function is regulated by a network of ion channels and transporters in the plasma membrane of B and T cells. These proteins modulate the cytoplasmic concentrations of diverse cations, such as calcium, magnesium and zinc ions, which function as second messengers to regulate crucial lymphocyte effector functions, including cytokine production, differentiation and cytotoxicity. The repertoire of ion-conducting proteins includes calcium release-activated calcium (CRAC) channels, P2X receptors, transient receptor potential (TRP) channels, potassium channels, chloride channels and magnesium and zinc transporters. This Review discusses the roles of ion conduction pathways in lymphocyte function and immunity.
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Affiliation(s)
- Stefan Feske
- Department of Pathology, New York University Langone Medical Center, New York, New York 10016, USA.
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Jin Z, Mendu SK, Birnir B. GABA is an effective immunomodulatory molecule. Amino Acids 2011; 45:87-94. [PMID: 22160261 PMCID: PMC3680704 DOI: 10.1007/s00726-011-1193-7] [Citation(s) in RCA: 182] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 11/30/2011] [Indexed: 12/13/2022]
Abstract
In recent years, it has become clear that there is an extensive cross-talk between the nervous and the immune system. Somewhat surprisingly, the immune cells themselves do express components of the neuronal neurotransmitters systems. What role the neurotransmitters, their ion channels, receptors and transporters have in immune function and regulation is an emerging field of study. Several recent studies have shown that the immune system is capable of synthesizing and releasing the classical neurotransmitter GABA (γ-aminobutyric acid). GABA has a number of effects on the immune cells such as activation or suppression of cytokine secretion, modification of cell proliferation and GABA can even affect migration of the cells. The immune cells encounter GABA when released by the immune cells themselves or when the immune cells enter the brain. In addition, GABA can also be found in tissues like the lymph nodes, the islets of Langerhans and GABA is in high enough concentration in blood to activate, e.g., GABA-A channels. GABA appears to have a role in autoimmune diseases like multiple sclerosis, type 1 diabetes, and rheumatoid arthritis and may modulate the immune response to infections. In the near future, it will be important to work out what specific effects GABA has on the function of the different types of immune cells and determine the underlying mechanisms. In this review, we discuss some of the recent findings revealing the role of GABA as an immunomodulator.
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Affiliation(s)
- Zhe Jin
- Department of Neuroscience, Molecular Physiology and Neuroscience, Uppsala University, BMC, BOX 593, 75124 Uppsala, Sweden
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Oral treatment with γ-aminobutyric acid improves glucose tolerance and insulin sensitivity by inhibiting inflammation in high fat diet-fed mice. PLoS One 2011; 6:e25338. [PMID: 21966503 PMCID: PMC3178643 DOI: 10.1371/journal.pone.0025338] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Accepted: 09/01/2011] [Indexed: 01/14/2023] Open
Abstract
Adipocyte and β-cell dysfunction and macrophage-related chronic inflammation are critical for the development of obesity-related insulin resistance and type 2 diabetes mellitus (T2DM), which can be negatively regulated by Tregs. Our previous studies and those of others have shown that activation of γ-aminobutyric acid (GABA) receptors inhibits inflammation in mice. However, whether GABA could modulate high fat diet (HFD)-induced obesity, glucose intolerance and insulin resistance has not been explored. Here, we show that although oral treatment with GABA does not affect water and food consumption it inhibits the HFD-induced gain in body weights in C57BL/6 mice. Furthermore, oral treatment with GABA significantly reduced the concentrations of fasting blood glucose, and improved glucose tolerance and insulin sensitivity in the HFD-fed mice. More importantly, after the onset of obesity and T2DM, oral treatment with GABA inhibited the continual HFD-induced gain in body weights, reduced the concentrations of fasting blood glucose and improved glucose tolerance and insulin sensitivity in mice. In addition, oral treatment with GABA reduced the epididymal fat mass, adipocyte size, and the frequency of macrophage infiltrates in the adipose tissues of HFD-fed mice. Notably, oral treatment with GABA significantly increased the frequency of CD4(+)Foxp3(+) Tregs in mice. Collectively, our data indicated that activation of peripheral GABA receptors inhibited the HFD-induced glucose intolerance, insulin resistance, and obesity by inhibiting obesity-related inflammation and up-regulating Treg responses in vivo. Given that GABA is safe for human consumption, activators of GABA receptors may be valuable for the prevention of obesity and intervention of T2DM in the clinic.
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Tian J, Dang H, Kaufman DL. Combining antigen-based therapy with GABA treatment synergistically prolongs survival of transplanted ß-cells in diabetic NOD mice. PLoS One 2011; 6:e25337. [PMID: 21966502 PMCID: PMC3178649 DOI: 10.1371/journal.pone.0025337] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Accepted: 09/01/2011] [Indexed: 01/13/2023] Open
Abstract
Antigen-based therapies (ABTs) very effectively prevent the development of type 1 diabetes (T1D) when given to young nonobese diabetic (NOD) mice, however, they have little or no ability to reverse hyperglycemia in newly diabetic NOD mice. More importantly, ABTs have not yet demonstrated an ability to effectively preserve residual ß-cells in individuals newly diagnosed with type 1 diabetes (T1D). Accordingly, there is great interest in identifying new treatments that can be combined with ABTs to safely protect ß-cells in diabetic animals. The activation of γ-aminobutyric acid (GABA) receptors (GABA-Rs) on immune cells has been shown to prevent T1D, experimental autoimmune encephalomyelitis (EAE) and rheumatoid arthritis in mouse models. Based on GABA's ability to inhibit different autoimmune diseases and its safety profile, we tested whether the combination of ABT with GABA treatment could prolong the survival of transplanted ß-cells in newly diabetic NOD mice. Newly diabetic NOD mice were untreated, or given GAD/alum (20 or 100 µg) and placed on plain drinking water, or water containing GABA (2 or 6 mg/ml). Twenty-eight days later, they received syngenic pancreas grafts and were monitored for the recurrence of hyperglycemia. Hyperglycemia reoccurred in the recipients given plain water, GAD monotherapy, GABA monotherapy, GAD (20 µg)+GABA (2 mg/ml), GAD (20 µg)+GABA (6 mg/ml) and GAD (100 µg)+GABA (6 mg/ml) about 1, 2-3, 3, 2-3, 3-8 and 10-11 weeks post-transplantation, respectively. Thus, combined GABA and ABT treatment had a synergistic effect in a dose-dependent fashion. These findings suggest that co-treatment with GABA (or other GABA-R agonists) may provide a new strategy to safely enhance the efficacy of other therapeutics designed to prevent or reverse T1D, as well as other T cell-mediated autoimmune diseases.
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Affiliation(s)
- Jide Tian
- Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Hoa Dang
- Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Daniel L. Kaufman
- Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California, United States of America
- * E-mail:
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