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Shen S, Fu B, Deng L, Zhu G, Shi H, Tian G, Han C, Yi P, Peng L. Paeoniflorin protects chicken against APEC-induced acute lung injury by affecting the endocannabinoid system and inhibiting the PI3K/AKT and NF-κB signaling pathways. Poult Sci 2024; 103:103866. [PMID: 38833957 PMCID: PMC11179074 DOI: 10.1016/j.psj.2024.103866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 05/04/2024] [Accepted: 05/13/2024] [Indexed: 06/06/2024] Open
Abstract
Avian pathogenic Escherichia coli (APEC) is the causative agent of chicken colibacillosis. Paeoniflorin, a natural ingredient extracted from Paeonia lactiflora, has a variety of pharmacological effects including anti-inflammatory and immunomodulatory. However, its effects and mechanism in APEC-induced acute lung injury (ALI) in chicken is not clear. The aim of this study was to investigate the protective effect of paeoniflorin on APEC-induced ALI and its possible mechanism. Paeoniflorin (25, 50, and 100 mg/kg) was administered by gavage for 5 d starting at 9 d of age and the chicken were infected with APEC by intraperitoneal injection at 12 d of age. The tissues were collected after APEC infection for 36 h for analysis. The results showed that paeoniflorin significantly alleviated the symptoms, increased the survival rate and body weight gain of APEC-infected chicken, and improved the histopathological damages, and reduced APEC loads in lung tissues. In addition, paeoniflorin restored the gene expression of ZO-1, Occludin and Claudin-3 during APEC infection. Moreover, paeoniflorin pretreatment significantly affected the endocannabinoid system (ECs) by increasing DAGL, decreasing MAGL, increasing secretion of 2-AG. Then, paeoniflorin significantly decreased the secretion of IL-1β, IL-6 and TNF-α in lung tissues, and decreased the mRNA expression of CXCL8, CXCL12, CCL1, CCL5, and CCL17. In addition, paeoniflorin significantly reduced the phosphorylation levels of PI3K, AKT, P65, and IκB. In summary, we found that paeoniflorin inhibited APEC-induced ALI, and its mechanism may be through affecting ECs and inhibiting the activation of PI3K/AKT and NF-κB signaling pathways, which provides a new idea for the prevention and treatment of chicken colibacillosis.
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Affiliation(s)
- Siyang Shen
- College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, China
| | - Bendong Fu
- College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, China; State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Jilin University, Changchun, Jilin 130062, China
| | - Ling Deng
- College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, China
| | - Guoqiang Zhu
- Animal Husbandry and Veterinary Station, Diao town Zhangqiu district, Jinan, Shandong 250204, China
| | - Haitao Shi
- College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, China
| | - Guang Tian
- College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, China
| | - Chi Han
- College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, China
| | - Pengfei Yi
- College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, China; State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Jilin University, Changchun, Jilin 130062, China
| | - Luyuan Peng
- College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, China; State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Jilin University, Changchun, Jilin 130062, China.
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Hu W, Du L, Shao J, Qu Y, Zhang L, Zhang D, Cao L, Chen H, Bi S. Molecular and metabolic responses to immune stress in the jejunum of broiler chickens: transcriptomic and metabolomic analysis. Poult Sci 2024; 103:103621. [PMID: 38507829 PMCID: PMC10966091 DOI: 10.1016/j.psj.2024.103621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 02/17/2024] [Accepted: 03/01/2024] [Indexed: 03/22/2024] Open
Abstract
In the large poultry industry, where farmed chickens are fed at high density, the prevalence of pathogens and repeated vaccinations induce immune stress, which can significantly decrease the production performance and increase the mortality. This study was designed to shed light on the molecular mechanisms and metabolic pathways involved in immune stress through an in-depth analysis of transcriptomic and metabolomic changes in jejunum samples from the broilers. Two groups were established for the experiment: a control group and an LPS group. LPS group received an intraperitoneal injection of LPS solution at a dose of 250 μg per kg at 12, 14, 33, and 35 d of age, whereas the control group received a sterile saline injection. The severity of immune stress was assessed using the Disease Activity Index. A jejunal section was collected to measure the intestinal villus structure (villus length and crypt depth). RNA sequencing and metabolomics data analysis were conducted to reveal differentially expressed genes and metabolites. The results showed that the DAI index was increased and jejunal villus height/crypt depth was decreased in the LPS group. A total of 96 differentially expressed genes and 672 differentially accumulating metabolites were detected in the jejunum by LPS group compared to the control group. The comprehensive analysis of metabolomic and transcriptomic data showed that 23 pathways were enriched in the jejunum and that appetite, nutrient absorption, energy and substance metabolism disorders and ferroptosis play an important role in immune stress in broilers. Our findings provide a deeper understanding of the molecular and metabolic responses in broilers to LPS-induced immune stress, suggesting potential targets for therapeutic strategies to improve the production performance of broiler chickens.
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Affiliation(s)
- Weidong Hu
- Department of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Southwest University, Rongchang, Chongqing, 402460, P. R. China
| | - Lin Du
- Department of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Southwest University, Rongchang, Chongqing, 402460, P. R. China
| | - Jianjian Shao
- Department of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Southwest University, Rongchang, Chongqing, 402460, P. R. China
| | - Yiwen Qu
- Bureau of Agricultural and Rural of Guanghan City, Guanghan, Sichuan, 618399, P. R. China
| | - Li Zhang
- Hanzhong Animal Disease Prevention and Control Center, Hanzhong, Shanxi, 723099, P. R. China
| | - Dezhi Zhang
- Department of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Southwest University, Rongchang, Chongqing, 402460, P. R. China
| | - Liting Cao
- Department of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Southwest University, Rongchang, Chongqing, 402460, P. R. China
| | - Hongwei Chen
- Department of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Southwest University, Rongchang, Chongqing, 402460, P. R. China
| | - Shicheng Bi
- Department of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Southwest University, Rongchang, Chongqing, 402460, P. R. China; Institute of Traditional Chinese Veterinary Medicine, Southwest University, Rongchang, Chongqing, 402460, P. R. China.
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Liao YC, Lim YS, Chu PW, Chen SK. Inflammatory Milieu Induces Mitochondrial Alterations and Neuronal Activations in Hypothalamic POMC Neurons in a Time-Dependent Manner. Mol Neurobiol 2023; 60:1164-1178. [PMID: 36417103 DOI: 10.1007/s12035-022-03128-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 11/04/2022] [Indexed: 11/24/2022]
Abstract
Inflammation has been associated with numerous neurological disorders. Inflammatory environments trigger a series of cellular and physiological alterations in the brain. However, how inflammatory milieu affects neuronal physiology and how neuronal alterations progress in the inflammatory environments are not fully understood. In this study, we examined the effects of pro-inflammatory milieu on mitochondrial functions and neuronal activities in the hypothalamic POMC neurons. Treating mHypoA-POMC/GFP1 with the conditioned medium collected from LPS activated macrophage were employed to mimic the inflammatory milieu during hypothalamic inflammation. After a 24-h treatment, intracellular ROS/RNS levels were elevated, and the antioxidant enzymes were reduced. Mitochondrial respiration and mitochondrial functions, including basal respiratory rate, spared respiration capacity, and maximal respiration, were all significantly compromised by inflammatory milieu. Moreover, pro-inflammatory cytokines altered mitochondrial dynamics in a time-dependent manner, resulting in the elongation of mitochondria in POMC neurons after a 24-h treatment. Additionally, the increase of C-Fos and Pomc genes expression indicated that the neurons were activated upon the stimulation of inflammatory environment. This neuronal activation of were confirmed on the LPS-challenged mice. Collectively, a short-term to midterm exposure to inflammatory milieu stimulated metabolic switch and neuronal activation, whereas chronic exposure triggered the elevation of oxidative stress, the decrease of the mitochondrial respiration, and the alterations of mitochondrial dynamics.
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Affiliation(s)
- Yi-Chun Liao
- Institute of Neuroscience, National ChengChi University, No. 64, Sec. 2, Zhinan Rd., Wenshan District, 11605, Taipei, Taiwan
| | - Yeou San Lim
- Institute of Neuroscience, National ChengChi University, No. 64, Sec. 2, Zhinan Rd., Wenshan District, 11605, Taipei, Taiwan
| | - Pei-Wen Chu
- Institute of Neuroscience, National ChengChi University, No. 64, Sec. 2, Zhinan Rd., Wenshan District, 11605, Taipei, Taiwan
| | - Shau-Kwaun Chen
- Institute of Neuroscience, National ChengChi University, No. 64, Sec. 2, Zhinan Rd., Wenshan District, 11605, Taipei, Taiwan.
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Socs3 ablation in kisspeptin cells partially prevents lipopolysaccharide-induced body weight loss. Cytokine 2022; 158:155999. [PMID: 35985175 DOI: 10.1016/j.cyto.2022.155999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 07/25/2022] [Accepted: 08/02/2022] [Indexed: 11/22/2022]
Abstract
Many cytokines have been proposed to regulate reproduction due to their actions on hypothalamic kisspeptin cells, the main modulators of gonadotropin-releasing hormone (GnRH) neurons. Hormones such as leptin, prolactin and growth hormone are good examples of cytokines that lead to Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway activation, consequently exerting effects in kisspeptin neurons. Different studies have investigated how specific components of the JAK/STAT signaling pathway affect the functions of kisspeptin cells, but the role of the suppressor of cytokine signaling 3 (SOCS3) in mediating cytokine actions in kisspeptin cells remains unknown. Cre-Loxp technology was used in the present study to ablate Socs3 expression in kisspeptin cells (Kiss1/Socs3-KO). Then, male and female control and Kiss1/Socs3-KO mice were evaluated for sexual maturation, energy homeostasis features, and fertility. It was found that hypothalamic Kiss1 mRNA expression is significantly downregulated in Kiss1/Socs3-KO mice. Despite reduced hypothalamic Kiss1 mRNA content, these mice did not present any sexual maturation or fertility impairments. Additionally, body weight gain, leptin sensitivity and glucose homeostasis were similar to control mice. Interestingly, Kiss1/Socs3-KO mice were partially protected against lipopolysaccharide (LPS)-induced body weight loss. Our results suggest that Socs3 ablation in kisspeptin cells partially prevents the sickness behavior induced by LPS, suggesting that kisspeptin cells can modulate energy metabolism in mice in certain situations.
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Cheng X, Cao Z, Luo J, Hu R, Cao H, Guo X, Xing C, Yang F, Zhuang Y, Hu G. Baicalin ameliorates APEC-induced intestinal injury in chicks by inhibiting the PI3K/AKT-mediated NF-κB signaling pathway. Poult Sci 2021; 101:101572. [PMID: 34844111 PMCID: PMC8633683 DOI: 10.1016/j.psj.2021.101572] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 08/13/2021] [Accepted: 08/15/2021] [Indexed: 12/23/2022] Open
Abstract
Avian pathogenic Escherichia coli (APEC) is the causative agent of avian colibacillosis. Baicalin (BA) possesses multiple pharmacological effects, but the mechanism underlying its activity in APEC-induced intestinal injury remains unknown. This study aims to investigate the protective effects and possible mechanism of BA against APEC-induced intestinal injury. Sixty 1-day-old chicks were randomly divided into 4 groups: the control group (basal diet), E. coli group (basal diet), BAI10 group (10 mg/kg BA), and BAI20 group (20 mg/kg BA). After pretreatment with BA for 15 d and subsequent induction of APEC infection by pectoralis injection, the ileum was collected and analyzed. The results showed that BA-pretreatment demonstrated an alleviation of chicks in diarrhea rate, mortality, and histopathological changes in intestinal tissues after APEC infection. Additionally, following APEC infection, BA improved the intestinal barrier by elevating zona occludens (ZO)s (ZO-1, 2, 3), Claudins (Claudin1, 2, 3), Occludin, avian β-defensin (AvBD)s (AvBD1, 2, 4), lysozyme (Lyz) mRNA levels and ZO-1, Claudin1, and Occludin protein levels. Besides, the activities of total superoxide dismutase (T-SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) and the SOD-1 and CAT mRNA levels and SOD-1 protein level were elevated by BA pretreatment. BA pretreatment also decreased the malondialdehyde (MDA) content, heme oxygenase-1 (HO-1) and NADH quinone oxidoreductase 1 (NQO1) mRNA levels, and HO-1 protein level after APEC infection. BA alleviated the APEC-induced inflammatory response, including downregulating the mRNA levels of proinflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin [IL]-1β, IL-6, IL-8) and upregulating the mRNA levels of anti-inflammatory cytokines (IL-4, IL-10, IL-13, transforming growth factor-β [TGF-β]). Furthermore, BA decreased the mRNA and protein levels of phosphatidylinositol 3 kinase (PI3K), protein kinase B (AKT), and nuclear factor kappa-B (NF-κB) as well as the expression of the phosphorylated forms of these proteins after APEC infection. Collectively, our findings indicate that BA exerts a protective effect against APEC-induced intestinal injury in chicks by inhibiting the PI3K/AKT-mediated NF-κB pathway, suggesting that BA may be a potential therapeutic approach for avian colibacillosis.
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Affiliation(s)
- Xinyi Cheng
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, P. R. China
| | - Zhanyou Cao
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, P. R. China
| | - Junrong Luo
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, P. R. China
| | - Ruiming Hu
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, P. R. China
| | - Huabin Cao
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, P. R. China
| | - Xiaoquan Guo
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, P. R. China
| | - Chenghong Xing
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, P. R. China
| | - Fan Yang
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, P. R. China
| | - Yu Zhuang
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, P. R. China
| | - Guoliang Hu
- Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, P. R. China.
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Couasnay G, Madel MB, Lim J, Lee B, Elefteriou F. Sites of Cre-recombinase activity in mouse lines targeting skeletal cells. J Bone Miner Res 2021; 36:1661-1679. [PMID: 34278610 DOI: 10.1002/jbmr.4415] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 07/12/2021] [Accepted: 07/15/2021] [Indexed: 12/22/2022]
Abstract
The Cre/Lox system is a powerful tool in the biologist's toolbox, allowing loss-of-function and gain-of-function studies, as well as lineage tracing, through gene recombination in a tissue-specific and inducible manner. Evidence indicates, however, that Cre transgenic lines have a far more nuanced and broader pattern of Cre activity than initially thought, exhibiting "off-target" activity in tissues/cells other than the ones they were originally designed to target. With the goal of facilitating the comparison and selection of optimal Cre lines to be used for the study of gene function, we have summarized in a single manuscript the major sites and timing of Cre activity of the main Cre lines available to target bone mesenchymal stem cells, chondrocytes, osteoblasts, osteocytes, tenocytes, and osteoclasts, along with their reported sites of "off-target" Cre activity. We also discuss characteristics, advantages, and limitations of these Cre lines for users to avoid common risks related to overinterpretation or misinterpretation based on the assumption of strict cell-type specificity or unaccounted effect of the Cre transgene or Cre inducers. © 2021 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Greig Couasnay
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, USA
| | | | - Joohyun Lim
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Brendan Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Florent Elefteriou
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
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Gonçalves GHM, Tristão SM, Volpi RE, Almeida-Pereira G, de Carvalho Borges B, Donato J, de Castro M, Antunes-Rodrigues J, Elias LLK. STAT3 but Not ERK2 Is a Crucial Mediator Against Diet-Induced Obesity via VMH Neurons. Diabetes 2021; 70:1498-1507. [PMID: 33883215 DOI: 10.2337/db20-0658] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 04/18/2021] [Indexed: 11/13/2022]
Abstract
Leptin plays an important role in the protection against diet-induced obesity (DIO) by its actions in ventromedial hypothalamic (VMH) neurons. However, little is known about the intracellular mechanisms involved in these effects. To assess the role of the STAT3 and ERK2 signaling in neurons that express the steroidogenic factor 1 (SF1) in the VMH in energy homeostasis, we used cre-lox technology to generate male and female mice with specific disruption of STAT3 or ERK2 in SF1 neurons of the VMH. We demonstrated that the conditional knockout of STAT3 in SF1 neurons of the VMH did not affect body weight, food intake, energy expenditure, or glucose homeostasis in animals on regular chow. However, with high-fat diet (HFD) challenge, loss of STAT3 in SF1 neurons caused a significant increase in body weight, food intake, and energy efficiency that was more remarkable in females, which also showed a decrease in energy expenditure. In contrast, deletion of ERK2 in SF1 neurons of VMH did not have any impact on energy homeostasis in both regular diet and HFD conditions. In conclusion, STAT3 but not ERK2 signaling in SF1 neurons of VMH plays a crucial role in protection against DIO in a sex-specific pattern.
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Affiliation(s)
- Gabriel Henrique Marques Gonçalves
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Sabrina Mara Tristão
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Rafaella Eduarda Volpi
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Gislaine Almeida-Pereira
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Beatriz de Carvalho Borges
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | | | - Margaret de Castro
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - José Antunes-Rodrigues
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Lucila Leico Kagohara Elias
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
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Chaves FM, Mansano NS, Frazão R, Donato J. Tumor Necrosis Factor α and Interleukin-1β Acutely Inhibit AgRP Neurons in the Arcuate Nucleus of the Hypothalamus. Int J Mol Sci 2020; 21:ijms21238928. [PMID: 33255553 PMCID: PMC7728092 DOI: 10.3390/ijms21238928] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 11/19/2020] [Accepted: 11/20/2020] [Indexed: 12/31/2022] Open
Abstract
Obesity-associated low-grade inflammation favors weight gain, whereas systemic infection frequently leads to anorexia. Thus, inflammatory signals can either induce positive or negative energy balance. In this study, we used whole-cell patch-clamp to investigate the acute effects of three important proinflammatory cytokines, tumor necrosis factor α (TNF-α), interleukin-6, and interleukin-1β (IL-1β) on the membrane excitability of agouti-related peptide (AgRP)- or proopiomelanocortin (POMC)-producing neurons. We found that both TNF-α and IL-1β acutely inhibited the activity of 35-42% of AgRP-producing neurons, whereas very few POMC neurons were depolarized by TNF-α. Interleukin-6 induced no acute changes in the activity of AgRP or POMC neurons. Our findings indicate that the effect of TNF-α and IL-1β, especially on the activity of AgRP-producing neurons, may contribute to inflammation-induced anorexia observed during acute inflammatory conditions.
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Affiliation(s)
- Fernanda M. Chaves
- Departamento de Fisiologia e Biofísica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, Brazil;
| | - Naira S. Mansano
- Departamento de Anatomia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-900, Brazil;
| | - Renata Frazão
- Departamento de Anatomia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-900, Brazil;
- Correspondence: (R.F.); (J.D.J.)
| | - Jose Donato
- Departamento de Fisiologia e Biofísica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, Brazil;
- Correspondence: (R.F.); (J.D.J.)
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10
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Cara AL, Myers MG, Elias CF. Lack of AR in LepRb Cells Disrupts Ambulatory Activity and Neuroendocrine Axes in a Sex-Specific Manner in Mice. Endocrinology 2020; 161:bqaa110. [PMID: 32609838 PMCID: PMC7383963 DOI: 10.1210/endocr/bqaa110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 06/26/2020] [Indexed: 11/19/2022]
Abstract
Disorders of androgen imbalance, such as hyperandrogenism in females or hypoandrogenism in males, increase risk of visceral adiposity, type 2 diabetes, and infertility. Androgens act upon androgen receptors (AR) which are expressed in many tissues. In the brain, AR are abundant in hypothalamic nuclei involved in regulation of reproduction and energy homeostasis, yet the role of androgens acting via AR in specific neuronal populations has not been fully elucidated. Leptin receptor (LepRb)-expressing neurons coexpress AR predominantly in hypothalamic arcuate and ventral premammillary nuclei (ARH and PMv, respectively), with low colocalization in other LepRb neuronal populations, and very low colocalization in the pituitary gland and gonads. Deletion of AR from LepRb-expressing cells (LepRbΔAR) has no effect on body weight, energy expenditure, and glucose homeostasis in male and female mice. However, LepRbΔAR female mice show increased body length later in life, whereas male LepRbΔAR mice show an increase in spontaneous ambulatory activity. LepRbΔAR mice display typical pubertal timing, estrous cycles, and fertility, but increased testosterone levels in males. Removal of sex steroid negative feedback action induced an exaggerated rise in luteinizing hormone in LepRbΔAR males and follicle-stimulating hormone in LepRbΔAR females. Our findings show that AR can directly affect a subset of ARH and PMv neurons in a sex-specific manner and demonstrate specific androgenic actions in the neuroendocrine hypothalamus.
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Affiliation(s)
- Alexandra L Cara
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
| | - Martin G Myers
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
- Department of Obstetrics and Gynaecology, University of Michigan, Ann Arbor, Michigan
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Wójcik M, Herman AP, Zieba DA, Krawczyńska A. The Impact of Photoperiod on the Leptin Sensitivity and Course of Inflammation in the Anterior Pituitary. Int J Mol Sci 2020; 21:ijms21114153. [PMID: 32532062 PMCID: PMC7312887 DOI: 10.3390/ijms21114153] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/08/2020] [Accepted: 06/09/2020] [Indexed: 12/16/2022] Open
Abstract
Leptin has a modulatory impact on the course of inflammation, affecting the expression of proinflammatory cytokines and their receptors. Pathophysiological leptin resistance identified in humans occurs typically in sheep during the long-day photoperiod. This study aimed to determine the effect of the photoperiod with relation to the leptin-modulating action on the expression of the proinflammatory cytokines and their receptors in the anterior pituitary under physiological or acute inflammation. Two in vivo experiments were conducted on 24 blackface sheep per experiment in different photoperiods. The real-time PCR analysis for the expression of the genes IL1B, IL1R1, IL1R2, IL6, IL6R, IL6ST, TNF, TNFR1, and TNFR2 was performed. Expression of all examined genes, except IL1β and IL1R2, was higher during short days. The leptin injection increased the expression of all examined genes during short days. In short days the synergistic effect of lipopolysaccharide and leptin increased the expression of IL1B, IL1R1, IL1R2, IL6, TNF, and TNFR2, and decreased expression of IL6ST. This mechanism was inhibited during long days for the expression of IL1R1, IL6, IL6ST, and TNFR1. The obtained results suggest the occurrence of leptin resistance during long days and suggest that leptin modulates the course of inflammation in a photoperiod-dependent manner in the anterior pituitary.
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Affiliation(s)
- Maciej Wójcik
- The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, ul. Instytucka 3, 05-110 Jabłonna, Poland; (A.P.H.); (A.K.)
- Correspondence:
| | - Andrzej Przemysław Herman
- The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, ul. Instytucka 3, 05-110 Jabłonna, Poland; (A.P.H.); (A.K.)
| | - Dorota Anna Zieba
- Laboratory of Biotechnology and Genomics, Department of Nutrition, Animal Biotechnology and Fisheries, Agricultural University of Krakow, 30-248 Krakow, Poland;
| | - Agata Krawczyńska
- The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, ul. Instytucka 3, 05-110 Jabłonna, Poland; (A.P.H.); (A.K.)
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12
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Ibrahim S, Zhu X, Luo X, Feng Y, Wang J. PIK3R3 regulates ZO-1 expression through the NF-kB pathway in inflammatory bowel disease. Int Immunopharmacol 2020; 85:106610. [PMID: 32473571 DOI: 10.1016/j.intimp.2020.106610] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 05/05/2020] [Accepted: 05/14/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS Inflammatory bowel disease (IBD) are the major risk factor for developing colitis associated cancer (CAC). Previously, we have reported that Phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3) was overexpressed in colorectal cancer (CRC), but we don't know the role of PIK3R3 in IBD. METHODS We investigated the differential expression of PIK3R3 and ZO-1 in IBD patients by using Immunohistochemical (IHC) and Gene Expression Omnibus (GEO) database analysis. Caco-2 cells were exposed to different conditions to assess protein level changes of PIK3R3 and ZO-1. Caco-2 cell monolayers were transfected with PIK3R3/siPIK3R3 to assess transepithelial electrical resistance. Tight junction protein integrity was assessed by immunoblot and immunofluorescence. For further, intestinal permeability and tight junction protein integrity were assessed in animal study to assess the treatment role of PIK3R3 specific inhibitor TAT-N 15 (N15). RESULTS PIK3R3 was increased in IBD patients, and negatively controlled the expression of ZO-1. In vitro, PIK3R3 regulates ZO-1 by activating NF-kB pathway. Overexpression of PIK3R3 in Caco-2 cells decreased transepithelial electrical resistance (TEER), an opposite result was observed in siPIK3R3 cells. In animal study, inhibition of PIK3R3 by N15 contributed to amelioration of DSS-induced intestinal permeability. Mice treated with N15 exhibited less disruption of TJs in colon tissues. CONCLUSIONS PIK3R3 was increased in clinical IBD patients with accompanying disruption of ZO-1 expression. Inhibition of PIK3R3 attenuated DSS-induced IBD symptoms in a mouse model. These findings indicated that PIK3R3 could be a therapeutic target for IBD.
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Affiliation(s)
- Sidikjan Ibrahim
- Department of Gastrointestinal Surgery Center, Tongji Hospital, Huazhong University of Science and Technology, Wuhan 430030, China.
| | - Xu Zhu
- Department of Gastrointestinal Surgery Center, Tongji Hospital, Huazhong University of Science and Technology, Wuhan 430030, China; Renmin Hospital, Wuhan University, Wuhan 430060, China.
| | - Xuelai Luo
- Department of Gastrointestinal Surgery Center, Tongji Hospital, Huazhong University of Science and Technology, Wuhan 430030, China.
| | - Yongdong Feng
- Department of Gastrointestinal Surgery Center, Tongji Hospital, Huazhong University of Science and Technology, Wuhan 430030, China.
| | - Jing Wang
- Department of Immunology, Basic Medicine School, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
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13
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Garcia-Galiano D, Borges BC, Allen SJ, Elias CF. PI3K signalling in leptin receptor cells: Role in growth and reproduction. J Neuroendocrinol 2019; 31:e12685. [PMID: 30618188 PMCID: PMC6533139 DOI: 10.1111/jne.12685] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 01/04/2019] [Accepted: 01/04/2019] [Indexed: 12/15/2022]
Abstract
Nutrition and growth are important signals for pubertal development, although how they are perceived and integrated in brain circuits has not been well defined. Growth hormones and metabolic cues both recruit phosphatidylinositol 3-kinase (PI3K) signalling in hypothalamic sites, although whether they converge into the same neuronal population(s) is also not known. In this review, we discuss recent findings from our laboratory showing the role of PI3K subunits in cells directly responsive to the adipocyte-derived hormone leptin in the coordination of growth, pubertal development and fertility. Mice with deletion of PI3K p110α and p110β catalytic subunits in leptin receptor cells (LRΔα+β ) have a lean phenotype associated with increased energy expenditure, locomotor activity and thermogenesis. The LRΔα+β mice also show deficient growth and delayed puberty. Deletion of a single subunit (ie, p110α) in LR cells (LRΔα ) causes a similar phenotype of increased energy expenditure, deficient growth and delayed pubertal development, indicating that these functions are preferably controlled by p110α. The LRΔα mice show enhanced leptin sensitivity in metabolic regulation but, remarkably, these mice are unresponsive to the effects of leptin on growth and puberty. PI3K is also recruited by insulin and a subpopulation of LR neurones is responsive to i.c.v. insulin administration. Deletion of insulin receptor in LR cells causes no changes in body weight or linear growth and induces only a mild delay in pubertal completion. Our findings demonstrate that PI3K in LR cells plays an essential role in growth and reproduction. We will also discuss the potential neural pathways underlying these effects.
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Affiliation(s)
- David Garcia-Galiano
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Beatriz C. Borges
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Kresge Hearing Research Institute and Department of Otolaryngology - Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Susan J. Allen
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Carol F. Elias
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, USA
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14
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Orlova EG, Shirshev SV, Loginova OA. Mechanisms of Leptin and Ghrelin Action on Maturation and Functions of Dendritic Cells. BIOCHEMISTRY (MOSCOW) 2019; 84:1-10. [PMID: 30927520 DOI: 10.1134/s0006297919010012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Molecular mechanisms of the immunomodulatory effects of leptin and ghrelin in concentrations typical for pregnancy on the maturation and functional activity of dendritic cells (DCs) generated from the peripheral blood monocytes of women are investigated. The presence of leptin during DC maturation did not affect the levels of CD83+CD1c+, CD86+CD1c+, and HLA-DR+CD1c+ DCs, but increased the amount and the activity of the enzyme indoleamine 2,3-dioxygenase (IDO). Cell culturing in the presence of ghrelin or combination of leptin and ghrelin reduced the percentage of CD86+CD1c+ DCs but did not affect the levels of CD83+CD1c+ and HLA-DR+CD1c+ DCs. In addition, ghrelin reduced the number of IDO molecules without affecting its activity. Simultaneous presence of leptin and ghrelin increased induced IDO activity without affecting the amount of the enzyme in DCs. The effects of leptin and ghrelin on the investigated functions of DCs in some cases correlated with high levels of cAMP. New mechanisms for leptin and ghrelin regulation of tolerogenic functions of DCs in pregnancy are proposed.
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Affiliation(s)
- E G Orlova
- Perm Federal Research Center, Institute of Ecology and Genetics of Microorganisms, Ural Branch of the Russian Academy of Sciences, Perm, 614081, Russia.
| | - S V Shirshev
- Perm Federal Research Center, Institute of Ecology and Genetics of Microorganisms, Ural Branch of the Russian Academy of Sciences, Perm, 614081, Russia
| | - O A Loginova
- Perm Federal Research Center, Institute of Ecology and Genetics of Microorganisms, Ural Branch of the Russian Academy of Sciences, Perm, 614081, Russia
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15
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Bresnick AR, Backer JM. PI3Kβ-A Versatile Transducer for GPCR, RTK, and Small GTPase Signaling. Endocrinology 2019; 160:536-555. [PMID: 30601996 PMCID: PMC6375709 DOI: 10.1210/en.2018-00843] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 12/20/2018] [Indexed: 12/17/2022]
Abstract
The phosphoinositide 3-kinase (PI3K) family includes eight distinct catalytic subunits and seven regulatory subunits. Only two PI3Ks are directly regulated downstream from G protein-coupled receptors (GPCRs): the class I enzymes PI3Kβ and PI3Kγ. Both enzymes produce phosphatidylinositol 3,4,5-trisposphate in vivo and are regulated by both heterotrimeric G proteins and small GTPases from the Ras or Rho families. However, PI3Kβ is also regulated by direct interactions with receptor tyrosine kinases (RTKs) and their tyrosine phosphorylated substrates, and similar to the class II and III PI3Ks, it binds activated Rab5. The unusually complex regulation of PI3Kβ by small and trimeric G proteins and RTKs leads to a rich landscape of signaling responses at the cellular and organismic levels. This review focuses first on the regulation of PI3Kβ activity in vitro and in cells, and then summarizes the biology of PI3Kβ signaling in distinct tissues and in human disease.
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Affiliation(s)
- Anne R Bresnick
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York
| | - Jonathan M Backer
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York
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16
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Borges BC, Han X, Allen SJ, Garcia-Galiano D, Elias CF. Insulin signaling in LepR cells modulates fat and glucose homeostasis independent of leptin. Am J Physiol Endocrinol Metab 2019; 316:E121-E134. [PMID: 30376348 PMCID: PMC6417687 DOI: 10.1152/ajpendo.00287.2018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hypothalamic neurons detect changes in circulating hormones such as leptin and insulin and put forward outputs to sustain energy and glucose homeostasis. Because leptin and insulin receptors colocalize in ~40-60% of neurons in the hypothalamus, we characterized the metabolic phenotype of mice with selective deletion of the insulin receptor (InsR) in LepR cells. LRΔInsR mice presented no difference in body weight and insulin levels but increased fat mass. In the light phase, LRΔInsR mice exhibited increased food intake, locomotor activity, carbon dioxide production, and respiratory exchange rate. These mice showed reduced fat oxidation and reduced expression of cluster of differentiation 36 and AMP-activated protein kinase-α1 in the liver, increased glucose oxidation in the light phase, and overall reduced basal glucose levels. To verify the impact of InsR deletion in LepR cells in obesity, we generated ob/ ob InsRfl, ob/ ob LRcre, and ob/ ob LRΔInsR mice. The ob/ ob LRΔInsR mice had higher body weight, fat mass, and expression of genes related to fat metabolism in the liver. No difference in food intake despite increased neuropeptide Y and agouti-related peptide expression, and no difference in energy expenditure, fat, or glucose oxidation was found in ob/ ob LRΔInsR compared with LRcre or LRΔInsR controls. Remarkably, basal glucose levels were reduced, and the expression of genes associated with glucose metabolism in the liver was higher. Insulin signaling in LepR cells is required for the proper fat and glucose oxidation. These effects are independent of leptin given that the leptin-deficient ob/ ob LRΔInsR mice also presented reduced glycemia and higher adiposity. The mechanisms underlying these responses remain to be unveiled.
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Affiliation(s)
- Beatriz C Borges
- Department of Molecular and Integrative Physiology, University of Michigan , Ann Arbor, Michigan
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo , Brazil
| | - Xingfa Han
- Department of Molecular and Integrative Physiology, University of Michigan , Ann Arbor, Michigan
- Isotope Research Laboratory, Sichuan Agricultural University, Ya'an, People's Republic of China
| | - Susan J Allen
- Department of Molecular and Integrative Physiology, University of Michigan , Ann Arbor, Michigan
| | - David Garcia-Galiano
- Department of Molecular and Integrative Physiology, University of Michigan , Ann Arbor, Michigan
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan , Ann Arbor, Michigan
- Department of Obstetrics and Gynecology, University of Michigan , Ann Arbor, Michigan
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17
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Chu SC, Chen PN, Chen JR, Yu CH, Hsieh YS, Kuo DY. Role of hypothalamic leptin-LepRb signaling in NPY-CART-mediated appetite suppression in amphetamine-treated rats. Horm Behav 2018; 98:173-182. [PMID: 29307696 DOI: 10.1016/j.yhbeh.2017.12.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 12/22/2017] [Accepted: 12/29/2017] [Indexed: 12/15/2022]
Abstract
Leptin is an adipose tissue hormone which plays an important role in regulating energy homeostasis. Amphetamine (AMPH) is a drug of appetite suppressant, which exerts its effect by decreasing the expression of hypothalamic neuropeptide Y (NPY) and increasing that of cocaine- and amphetamine-regulated transcript (CART). This study investigated whether leptin, the leptin receptor (LepRb) and the signal transducer and activator of transcription-3 (STAT3) were involved in NPY/CART-mediated appetite suppression in AMPH-treated rats. Rats were given AMPH daily for four days, and changes in the levels of blood leptin and hypothalamic NPY, CART, LepRb, Janus kinases 2 (JAK2), and STAT3 were assessed and compared. During the AMPH treatment, blood leptin levels and hypothalamic NPY expression decreased, with the largest reduction observed on Day 2. By contrast, the expression of hypothalamic CART, LepRb, JAK2, and STAT3 increased, with the maximum response on Day 2. Furthermore, the binding activity of pSTAT3/DNA increased and was expressed in similar pattern to that of CART, LepRb, and JAK2. An intracerebroventricular infusion of NPY antisense 60min prior to AMPH treatment increased the levels of leptin, as well as the expression in LepRb, JAK2, and CART, whereas an infusion of STAT3 antisense decreased these levels and the expression of these parameters. The results suggest that blood leptin and hypothalamic LepRb-JAK2-STAT3 signaling involved in NPY-CART-regulated appetite suppression in AMPH-treated rats. The findings may aid understanding the role of leptin-LepRb during the treatment of anorectic drugs.
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Affiliation(s)
- Shu-Chen Chu
- Department of Food Science, Central Taiwan University of Science and Technology, Taichung City 406, Taiwan
| | - Pei-Ni Chen
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Chung Shan Medical University Hospital, Taichung City 40201, Taiwan
| | - Jeng-Rung Chen
- Department of Veterinary Medicine, National Chung Hsing University, Taichung City 40201, Taiwan
| | - Ching-Han Yu
- Department of Physiology, Chung Shan Medical University, Chung Shan Medical University Hospital, Taichung City 40201, Taiwan
| | - Yih-Shou Hsieh
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Chung Shan Medical University Hospital, Taichung City 40201, Taiwan
| | - Dong-Yih Kuo
- Department of Physiology, Chung Shan Medical University, Chung Shan Medical University Hospital, Taichung City 40201, Taiwan.
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18
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Garcia-Galiano D, Borges BC, Donato J, Allen SJ, Bellefontaine N, Wang M, Zhao JJ, Kozloff KM, Hill JW, Elias CF. PI3Kα inactivation in leptin receptor cells increases leptin sensitivity but disrupts growth and reproduction. JCI Insight 2017; 2:96728. [PMID: 29212950 DOI: 10.1172/jci.insight.96728] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 10/23/2017] [Indexed: 12/13/2022] Open
Abstract
The role of PI3K in leptin physiology has been difficult to determine due to its actions downstream of several metabolic cues, including insulin. Here, we used a series of mouse models to dissociate the roles of specific PI3K catalytic subunits and of insulin receptor (InsR) downstream of leptin signaling. We show that disruption of p110α and p110β subunits in leptin receptor cells (LRΔα+β) produces a lean phenotype associated with increased energy expenditure, locomotor activity, and thermogenesis. LRΔα+β mice have deficient growth and delayed puberty. Single subunit deletion (i.e., p110α in LRΔα) resulted in similarly increased energy expenditure, deficient growth, and pubertal development, but LRΔα mice have normal locomotor activity and thermogenesis. Blunted PI3K in leptin receptor (LR) cells enhanced leptin sensitivity in metabolic regulation due to increased basal hypothalamic pAKT, leptin-induced pSTAT3, and decreased PTEN levels. However, these mice are unresponsive to leptin's effects on growth and puberty. We further assessed if these phenotypes were associated with disruption of insulin signaling. LRΔInsR mice have no metabolic or growth deficit and show only mild delay in pubertal completion. Our findings demonstrate that PI3K in LR cells plays an essential role in energy expenditure, growth, and reproduction. These actions are independent from insulin signaling.
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Affiliation(s)
- David Garcia-Galiano
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Beatriz C Borges
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA.,Department of Physiology and
| | - Jose Donato
- Department of Physiology and Biophysics, University of São Paulo, São Paulo, Brazil
| | - Susan J Allen
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Nicole Bellefontaine
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Mengjie Wang
- Department of Physiology and Pharmacology, University of Toledo, Toledo, Ohio, USA
| | - Jean J Zhao
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA
| | | | - Jennifer W Hill
- Department of Physiology and Pharmacology, University of Toledo, Toledo, Ohio, USA
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA.,Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan, USA
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19
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Holzer P, Farzi A, Hassan AM, Zenz G, Jačan A, Reichmann F. Visceral Inflammation and Immune Activation Stress the Brain. Front Immunol 2017; 8:1613. [PMID: 29213271 PMCID: PMC5702648 DOI: 10.3389/fimmu.2017.01613] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Accepted: 11/07/2017] [Indexed: 12/20/2022] Open
Abstract
Stress refers to a dynamic process in which the homeostasis of an organism is challenged, the outcome depending on the type, severity, and duration of stressors involved, the stress responses triggered, and the stress resilience of the organism. Importantly, the relationship between stress and the immune system is bidirectional, as not only stressors have an impact on immune function, but alterations in immune function themselves can elicit stress responses. Such bidirectional interactions have been prominently identified to occur in the gastrointestinal tract in which there is a close cross-talk between the gut microbiota and the local immune system, governed by the permeability of the intestinal mucosa. External stressors disturb the homeostasis between microbiota and gut, these disturbances being signaled to the brain via multiple communication pathways constituting the gut-brain axis, ultimately eliciting stress responses and perturbations of brain function. In view of these relationships, the present article sets out to highlight some of the interactions between peripheral immune activation, especially in the visceral system, and brain function, behavior, and stress coping. These issues are exemplified by the way through which the intestinal microbiota as well as microbe-associated molecular patterns including lipopolysaccharide communicate with the immune system and brain, and the mechanisms whereby overt inflammation in the GI tract impacts on emotional-affective behavior, pain sensitivity, and stress coping. The interactions between the peripheral immune system and the brain take place along the gut-brain axis, the major communication pathways of which comprise microbial metabolites, gut hormones, immune mediators, and sensory neurons. Through these signaling systems, several transmitter and neuropeptide systems within the brain are altered under conditions of peripheral immune stress, enabling adaptive processes related to stress coping and resilience to take place. These aspects of the impact of immune stress on molecular and behavioral processes in the brain have a bearing on several disturbances of mental health and highlight novel opportunities of therapeutic intervention.
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Affiliation(s)
- Peter Holzer
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Graz, Austria.,BioTechMed-Graz, Graz, Austria
| | - Aitak Farzi
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Graz, Austria
| | - Ahmed M Hassan
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Graz, Austria
| | - Geraldine Zenz
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Graz, Austria
| | - Angela Jačan
- CBmed GmbH-Center for Biomarker Research in Medicine, Graz, Austria
| | - Florian Reichmann
- Research Unit of Translational Neurogastroenterology, Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Graz, Austria
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20
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Orlova EG, Shirshev SV. Role of PKA and PI3K in leptin and ghrelin regulation of adaptive subpopulations of regulatory CD4+ T-lymphocyte formation. BIOCHEMISTRY (MOSCOW) 2017; 82:1061-1072. [DOI: 10.1134/s0006297917090103] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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21
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LPS-Induced Low-Grade Inflammation Increases Hypothalamic JNK Expression and Causes Central Insulin Resistance Irrespective of Body Weight Changes. Int J Mol Sci 2017; 18:ijms18071431. [PMID: 28677618 PMCID: PMC5535922 DOI: 10.3390/ijms18071431] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 06/22/2017] [Accepted: 06/27/2017] [Indexed: 01/26/2023] Open
Abstract
Metabolic endotoxemia contributes to low-grade inflammation in obesity, which causes insulin resistance due to the activation of intracellular proinflammatory pathways, such as the c-Jun N-terminal Kinase (JNK) cascade in the hypothalamus and other tissues. However, it remains unclear whether the proinflammatory process precedes insulin resistance or it appears because of the development of obesity. Hypothalamic low-grade inflammation was induced by prolonged lipopolysaccharide (LPS) exposure to investigate if central insulin resistance is induced by an inflammatory stimulus regardless of obesity. Male Wistar rats were treated with single (1 LPS) or repeated injections (6 LPS) of LPS (100 μg/kg, IP) to evaluate the phosphorylation of the insulin receptor substrate-1 (IRS1), Protein kinase B (AKT), and JNK in the hypothalamus. Single LPS increased the expression of pIRS1, pAKT, and pJNK, whereas the repeated LPS treatment failed to recruit pIRS1 and pAKT. The 6 LPS treated rats showed increased total JNK and pJNK. The 6 LPS rats became unresponsive to the hypophagic effect induced by central insulin administration (12 μM/5 μL, ICV). Prolonged exposure to LPS (24 h) impaired the insulin-induced AKT phosphorylation and the translocation of the transcription factor forkhead box protein O1 (FoxO1) from the nucleus to the cytoplasm of the cultured hypothalamic GT1-7 cells. Central administration of the JNK inhibitor (20 μM/5 μL, ICV) restored the ability of insulin to phosphorylate IRS1 and AKT in 6 LPS rats. The present data suggest that an increased JNK activity in the hypothalamus underlies the development of insulin resistance during prolonged exposure to endotoxins. Our study reveals that weight gain is not mandatory for the development of hypothalamic insulin resistance and the blockade of proinflammatory pathways could be useful for restoring the insulin signaling during prolonged low-grade inflammation as seen in obesity.
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22
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Mohsen Z, Sim H, Garcia-Galiano D, Han X, Bellefontaine N, Saunders TL, Elias CF. Sexually dimorphic distribution of Prokr2 neurons revealed by the Prokr2-Cre mouse model. Brain Struct Funct 2017; 222:4111-4129. [PMID: 28616754 DOI: 10.1007/s00429-017-1456-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 06/05/2017] [Indexed: 01/18/2023]
Abstract
Prokineticin receptor 2 (PROKR2) is predominantly expressed in the mammalian central nervous system. Loss-of-function mutations of PROKR2 in humans are associated with Kallmann syndrome due to the disruption of gonadotropin releasing hormone neuronal migration and deficient olfactory bulb morphogenesis. PROKR2 has been also implicated in the neuroendocrine control of GnRH neurons post-migration and other physiological systems. However, the brain circuitry and mechanisms associated with these actions have been difficult to investigate mainly due to the widespread distribution of Prokr2-expressing cells, and the lack of animal models and molecular tools. Here, we describe the generation, validation and characterization of a new mouse model that expresses Cre recombinase driven by the Prokr2 promoter, using CRISPR-Cas9 technology. Cre expression was visualized using reporter genes, tdTomato and GFP, in males and females. Expression of Cre-induced reporter genes was found in brain sites previously described to express Prokr2, e.g., the paraventricular and the suprachiasmatic nuclei, and the area postrema. The Prokr2-Cre mouse model was further validated by colocalization of Cre-induced GFP and Prokr2 mRNA. No disruption of Prokr2 expression, GnRH neuronal migration or fertility was observed. Comparative analysis of Prokr2-Cre expression in male and female brains revealed a sexually dimorphic distribution confirmed by in situ hybridization. In females, higher Cre activity was found in the medial preoptic area, ventromedial nucleus of the hypothalamus, arcuate nucleus, medial amygdala and lateral parabrachial nucleus. In males, Cre was higher in the amygdalo-hippocampal area. The sexually dimorphic pattern of Prokr2 expression indicates differential roles in reproductive function and, potentially, in other physiological systems.
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Affiliation(s)
- Zaid Mohsen
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA
| | - Hosung Sim
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA
| | - David Garcia-Galiano
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA
| | - Xingfa Han
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA.,Isotope Research Lab, Sichuan Agricultural University, Ya'an, 625014, People's Republic of China
| | - Nicole Bellefontaine
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA
| | - Thomas L Saunders
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA.,University of Michigan Transgenic Animal Model Core, Ann Arbor, MI, USA
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan, 1137 E. Catherine St., 7732B Med Sci II, Ann Arbor, MI, 48109-5622, USA. .,Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, USA.
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23
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Wauman J, Zabeau L, Tavernier J. The Leptin Receptor Complex: Heavier Than Expected? Front Endocrinol (Lausanne) 2017; 8:30. [PMID: 28270795 PMCID: PMC5318964 DOI: 10.3389/fendo.2017.00030] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 02/01/2017] [Indexed: 12/31/2022] Open
Abstract
Under normal physiological conditions, leptin and the leptin receptor (ObR) regulate the body weight by balancing food intake and energy expenditure. However, this adipocyte-derived hormone also directs peripheral processes, including immunity, reproduction, and bone metabolism. Leptin, therefore, can act as a metabolic switch connecting the body's nutritional status to high energy consuming processes. We provide an extensive overview of current structural insights on the leptin-ObR interface and ObR activation, coupling to signaling pathways and their negative regulation, and leptin functioning under normal and pathophysiological conditions (obesity, autoimmunity, cancer, … ). We also discuss possible cross-talk with other receptor systems on the receptor (extracellular) and signaling cascade (intracellular) levels.
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Affiliation(s)
- Joris Wauman
- Cytokine Receptor Laboratory, Faculty of Medicine and Health Sciences, Department of Biochemistry, Ghent University, Ghent, Belgium
- VIB Medical Biotechnology Center, VIB, Ghent, Belgium
| | - Lennart Zabeau
- Cytokine Receptor Laboratory, Faculty of Medicine and Health Sciences, Department of Biochemistry, Ghent University, Ghent, Belgium
- VIB Medical Biotechnology Center, VIB, Ghent, Belgium
| | - Jan Tavernier
- Cytokine Receptor Laboratory, Faculty of Medicine and Health Sciences, Department of Biochemistry, Ghent University, Ghent, Belgium
- VIB Medical Biotechnology Center, VIB, Ghent, Belgium
- *Correspondence: Jan Tavernier,
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Borges BC, Elias CF, Elias LLK. PI3K signaling: A molecular pathway associated with acute hypophagic response during inflammatory challenges. Mol Cell Endocrinol 2016; 438:36-41. [PMID: 27389879 PMCID: PMC5116261 DOI: 10.1016/j.mce.2016.07.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 06/30/2016] [Accepted: 07/03/2016] [Indexed: 12/13/2022]
Abstract
Energy balance has in the hypothalamus a central component of integration of food intake and energy expenditure. An accumulating body of evidence indicates that energy homeostasis is largely affected by inflammatory challenges. Severe undernutrition caused by exacerbated inflammatory response may lead to cachexia. On the other hand, prolonged low-grade inflammation such as that observed in obesity and metabolic syndrome, raises the risk for the development of diabetes and heart diseases. Changes in circulating insulin and cytokines such as leptin, interleukins and tumor necrosis factor, as well as changes in their action in the hypothalamus drive the inhibition of food consumption during inflammation. The molecular pathways associated with these responses have only started to be unraveled. One potential candidate is the PI3K signaling, an important player in distinct hypothalamic neurons that control food intake. This study presents an overview of the current knowledge about PI3K role on cytokines and insulin signaling in the hypothalamic regulation of feeding during inflammation.
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Affiliation(s)
- Beatriz C Borges
- Department of Molecular and Integrative Physiology, University of Michigan, United States; Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Brazil.
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan, United States; Department of Obstetrics and Gynecology, University of Michigan, United States.
| | - Lucila L K Elias
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Brazil.
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