1
|
Ehret F, Pelz MS, Senko AN, Soto KEG, Liu H, Kempermann G. Presymptomatic Reduction of Individuality in the App NL-F Knockin Model of Alzheimer's Disease. Biol Psychiatry 2023; 94:721-731. [PMID: 37076091 DOI: 10.1016/j.biopsych.2023.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 04/06/2023] [Accepted: 04/07/2023] [Indexed: 04/21/2023]
Abstract
BACKGROUND One-third of the risk for Alzheimer's disease is explained by environment and lifestyle, but Alzheimer's disease pathology might also affect lifestyle and thereby impair the individual potential for health behavior and prevention. METHODS We examined in mice how the AppNL-F/NL-F (NL-F) knockin mutation affects the presymptomatic response to environmental enrichment (ENR) as an experimental paradigm addressing nongenetic factors. We assessed the emergence of interindividual phenotypic variation under the condition that both the genetic background and the shared environment were held constant, thereby isolating the contribution of individual behavior (nonshared environment). RESULTS After 4 months of ENR, the mean and variability of plasma ApoE were increased in NL-F mice, suggesting a presymptomatic variation in pathogenic processes. Roaming entropy as a measure of behavioral activity was continuously assessed with radiofrequency identification (RFID) technology and revealed reduced habituation and variance in NL-F mice compared with control animals, which do not carry a Beyreuther/Iberian mutation. Intraindividual variation decreased, while behavioral stability was reduced in NL-F mice. Seven months after discontinuation of ENR, we found no difference in plaque size and number, but ENR increased variance in hippocampal plaque counts in NL-F mice. A reactive increase in adult hippocampal neurogenesis in NL-F mice, known from other models, was normalized by ENR. CONCLUSIONS Our data suggest that while NL-F has early effects on individual behavioral patterns in response to ENR, there are lasting effects on cellular plasticity even after the discontinuation of ENR. Hence, early behavior matters for maintaining individual behavioral trajectories and brain plasticity even under maximally constrained conditions.
Collapse
Affiliation(s)
- Fanny Ehret
- German Center for Neurodegenerative Diseases Dresden, Dresden, Germany; Center for Regenerative Therapies Technical University Dresden, Dresden, Germany; Institute of Anatomy, Faculty of Medicine Carl Gustav Carus, Technical University Dresden, Dresden, Germany
| | - Meike S Pelz
- German Center for Neurodegenerative Diseases Dresden, Dresden, Germany; Center for Regenerative Therapies Technical University Dresden, Dresden, Germany
| | - Anna N Senko
- German Center for Neurodegenerative Diseases Dresden, Dresden, Germany; Center for Regenerative Therapies Technical University Dresden, Dresden, Germany
| | - Karla E G Soto
- German Center for Neurodegenerative Diseases Dresden, Dresden, Germany; Center for Regenerative Therapies Technical University Dresden, Dresden, Germany
| | - Hang Liu
- German Center for Neurodegenerative Diseases Dresden, Dresden, Germany; Center for Regenerative Therapies Technical University Dresden, Dresden, Germany
| | - Gerd Kempermann
- German Center for Neurodegenerative Diseases Dresden, Dresden, Germany; Center for Regenerative Therapies Technical University Dresden, Dresden, Germany.
| |
Collapse
|
2
|
Nemoto S, Kubota T, Ohno H. Metabolic differences and differentially expressed genes between C57BL/6J and C57BL/6N mice substrains. PLoS One 2022; 17:e0271651. [PMID: 36548271 PMCID: PMC9778930 DOI: 10.1371/journal.pone.0271651] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 11/21/2022] [Indexed: 12/24/2022] Open
Abstract
C57BL/6J (B6J) and C57BL/6N (B6N) mice are the most frequently used substrains in C57BL/6 (B6) inbred mice, serving as physiological models for in vivo studies and as background strains to build transgenic mice. However, the differences in metabolic phenotypes between B6J and B6N mice are not coherent, and genotypic differences in metabolically important tissues have not been well studied. The phenotypic differences between B6J and B6N substrains have often been attributed to the role of the nicotinamide nucleotide transhydrogenase (Nnt) gene, whereby B6J has a spontaneous missense mutation of Nnt. Nevertheless, phenotypic differences between the two cannot be explained by Nnt mutations alone, especially in metabolic traits. Therefore, we aimed to investigate the genetic cause of the phenotypic differences between B6J and B6N mice. Determining consistent genetic differences across multiple tissues involved in metabolic traits such as subcutaneous and visceral white adipose tissues, brown adipose tissue, skeletal muscle, liver, hypothalamus, and hippocampus, may help explain phenotypic differences in metabolism between the two substrains. We report candidate genes along with comparative data on body weight, tissue weight, blood components involved in metabolism, and energy balance of B6J and B6N mice. Insulin degrading enzyme, adenylosuccinate synthase 2, and ectonucleotide triphosphate diphosphohydrolase 4 were highly expressed in B6J mice compared with those in B6N mice, and Nnt, WD repeat and FYVE domain containing 1, and dynein light chain Tctex-type 1 were less expressed in B6J mice compared with those in B6N mice in all seven tissues. Considering the extremely wide use of both substrains and their critical importance in generating transgenic and knock-out models, these findings guide future research across several interrelated fields.
Collapse
Affiliation(s)
- Shino Nemoto
- Laboratory for Intestinal Ecosystem, RIKEN Center for Integrative Medical Sciences, Kanagawa, Japan
- * E-mail:
| | - Tetsuya Kubota
- Laboratory for Intestinal Ecosystem, RIKEN Center for Integrative Medical Sciences, Kanagawa, Japan
- Division of Diabetes and Metabolism, The Institute of Medical Science, Asahi Life Foundation, Tokyo, Japan
- Department of Clinical Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Tokyo, Japan
- Division of Cardiovascular Medicine, Toho University Ohashi Medical Center, Tokyo, Japan
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroshi Ohno
- Laboratory for Intestinal Ecosystem, RIKEN Center for Integrative Medical Sciences, Kanagawa, Japan
- Laboratory for Immune Regulation, Graduate School of Medical and Pharmaceutical Sciences, Chiba University, Chiba, Japan
- Immunobiology Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama, Japan
| |
Collapse
|
3
|
Tff3 Deficiency Protects against Hepatic Fat Accumulation after Prolonged High-Fat Diet. LIFE (BASEL, SWITZERLAND) 2022; 12:life12081288. [PMID: 36013467 PMCID: PMC9409972 DOI: 10.3390/life12081288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/09/2022] [Accepted: 08/11/2022] [Indexed: 11/17/2022]
Abstract
Trefoil factor 3 (Tff3) protein is a small secretory protein expressed on various mucosal surfaces and is involved in proper mucosal function and recovery via various mechanisms, including immune response. However, Tff3 is also found in the bloodstream and in various other tissues, including the liver. Its complete attenuation was observed as the most prominent event in the early phase of diabetes in the polygenic Tally Ho mouse model of diabesity. Since then, its role in metabolic processes has emerged. To elucidate the complex role of Tff3, we used a new Tff3-deficient mouse model without additional metabolically relevant mutations (Tff3-/-/C57BL/6NCrl) and exposed it to a high-fat diet (HFD) for a prolonged period (8 months). The effect was observed in male and female mice compared to wild-type (WT) counter groups (n = 10 animals per group). We monitored the animals’ general metabolic parameters, liver morphology, ultrastructure and molecular genes in relevant lipid and inflammatory pathways. Tff3-deficient male mice had reduced body weight and better glucose utilization after 17 weeks of HFD, but longer HFD exposure (32 weeks) resulted in no such change. We found a strong reduction in lipid accumulation in male Tff3-/-/C57BL/6NCrl mice and a less prominent reduction in female mice. This was associated with downregulated peroxisome proliferator-activated receptor gamma (Pparγ) and upregulated interleukin-6 (Il-6) gene expression, although protein level difference did not reach statistical significance due to higher individual variations. Tff3-/-/C57Bl6N mice of both sex had reduced liver steatosis, without major fatty acid content perturbations. Our research shows that Tff3 protein is clearly involved in complex metabolic pathways. Tff3 deficiency in C57Bl6N genetic background caused reduced lipid accumulation in the liver; further research is needed to elucidate its precise role in metabolism-related events.
Collapse
|
4
|
Francisco A, Figueira TR, Castilho RF. Mitochondrial NAD(P) + Transhydrogenase: From Molecular Features to Physiology and Disease. Antioxid Redox Signal 2022; 36:864-884. [PMID: 34155914 DOI: 10.1089/ars.2021.0111] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Significance: Proton-translocating NAD(P)+ transhydrogenase, also known as nicotinamide nucleotide transhydrogenase (NNT), catalyzes a reversible reaction coupling the protonmotive force across the inner mitochondrial membrane and hydride (H-, a proton plus two electrons) transfer between the mitochondrial pools of NAD(H) and NADP(H). The forward NNT reaction is a source of NADPH in the mitochondrial matrix, fueling antioxidant and biosynthetic pathways with reductive potential. Despite the greater emphasis given to the net forward reaction, the reverse NNT reaction that oxidizes NADPH also occurs in physiological and pathological conditions. Recent Advances: NNT (dys)function has been linked to various metabolic pathways and disease phenotypes. Most of these findings have been based on spontaneous loss-of-function Nnt mutations found in the C57BL/6J mouse strain (NntC57BL/6J mutation) and disease-causing Nnt mutations in humans. The present review focuses on recent advances based on the mouse NntC57BL/6J mutation. Critical Issues: Most studies associating NNT function with disease phenotypes have been based on comparisons between different strains of inbred mice (with or without the NntC57BL/6J mutation), which creates uncertainties over the actual contribution of NNT in the context of other potential genetic modifiers. Future Directions: Future research might contribute to understanding the role of NNT in pathological conditions and elucidate how NNT regulates physiological signaling through its forward and reverse reactions. The importance of NNT in redox balance and tumor cell proliferation makes it a potential target of new therapeutic strategies for oxidative-stress-mediated diseases and cancer. Antioxid. Redox Signal. 36, 864-884.
Collapse
Affiliation(s)
- Annelise Francisco
- Department of Pathology, Faculty of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
| | - Tiago Rezende Figueira
- School of Physical Education and Sport of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, Brazil
| | - Roger Frigério Castilho
- Department of Pathology, Faculty of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
| |
Collapse
|
5
|
Rawle DJ, Le TT, Dumenil T, Bishop C, Yan K, Nakayama E, Bird PI, Suhrbier A. Widespread discrepancy in Nnt genotypes and genetic backgrounds complicates granzyme A and other knockout mouse studies. eLife 2022; 11:e70207. [PMID: 35119362 PMCID: PMC8816380 DOI: 10.7554/elife.70207] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 01/10/2022] [Indexed: 02/06/2023] Open
Abstract
Granzyme A (GZMA) is a serine protease secreted by cytotoxic lymphocytes, with Gzma-/- mouse studies having informed our understanding of GZMA's physiological function. We show herein that Gzma-/- mice have a mixed C57BL/6J and C57BL/6N genetic background and retain the full-length nicotinamide nucleotide transhydrogenase (Nnt) gene, whereas Nnt is truncated in C57BL/6J mice. Chikungunya viral arthritis was substantially ameliorated in Gzma-/- mice; however, the presence of Nnt and the C57BL/6N background, rather than loss of GZMA expression, was responsible for this phenotype. A new CRISPR active site mutant C57BL/6J GzmaS211A mouse provided the first insights into GZMA's bioactivity free of background issues, with circulating proteolytically active GZMA promoting immune-stimulating and pro-inflammatory signatures. Remarkably, k-mer mining of the Sequence Read Archive illustrated that ≈27% of Run Accessions and ≈38% of BioProjects listing C57BL/6J as the mouse strain had Nnt sequencing reads inconsistent with a C57BL/6J genetic background. Nnt and C57BL/6N background issues have clearly complicated our understanding of GZMA and may similarly have influenced studies across a broad range of fields.
Collapse
Affiliation(s)
- Daniel J Rawle
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
| | - Thuy T Le
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
| | - Troy Dumenil
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
| | - Cameron Bishop
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
| | - Kexin Yan
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
| | - Eri Nakayama
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
- Department of Virology I, National Institute of Infectious DiseasesTokyoJapan
| | - Phillip I Bird
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash UniversityMelbourneAustralia
| | - Andreas Suhrbier
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
- Australian Infectious Disease Research Centre, GVN Center of ExcellenceBrisbaneAustralia
| |
Collapse
|
6
|
HSP60 reduction protects against diet-induced obesity by modulating energy metabolism in adipose tissue. Mol Metab 2021; 53:101276. [PMID: 34153520 PMCID: PMC8319365 DOI: 10.1016/j.molmet.2021.101276] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 06/06/2021] [Accepted: 06/15/2021] [Indexed: 11/29/2022] Open
Abstract
Objective Insulin regulates mitochondrial function, thereby propagating an efficient metabolism. Conversely, diabetes and insulin resistance are linked to mitochondrial dysfunction with a decreased expression of the mitochondrial chaperone HSP60. The aim of this investigation was to determine the effect of a reduced HSP60 expression on the development of obesity and insulin resistance. Methods Control and heterozygous whole-body HSP60 knockout (Hsp60+/−) mice were fed a high-fat diet (HFD, 60% calories from fat) for 16 weeks and subjected to extensive metabolic phenotyping. To understand the effect of HSP60 on white adipose tissue, microarray analysis of gonadal WAT was performed, ex vivo experiments were performed, and a lentiviral knockdown of HSP60 in 3T3-L1 cells was conducted to gain detailed insights into the effect of reduced HSP60 levels on adipocyte homeostasis. Results Male Hsp60+/− mice exhibited lower body weight with lower fat mass. These mice exhibited improved insulin sensitivity compared to control, as assessed by Matsuda Index and HOMA-IR. Accordingly, insulin levels were significantly reduced in Hsp60+/− mice in a glucose tolerance test. However, Hsp60+/− mice exhibited an altered adipose tissue metabolism with elevated insulin-independent glucose uptake, adipocyte hyperplasia in the presence of mitochondrial dysfunction, altered autophagy, and local insulin resistance. Conclusions We discovered that the reduction of HSP60 in mice predominantly affects adipose tissue homeostasis, leading to beneficial alterations in body weight, body composition, and adipocyte morphology, albeit exhibiting local insulin resistance. Mice with reduced HSP60 levels are protected from diet-induced obesity. Hsp60+/− mice exhibit altered adipose tissue energy metabolism. WAT of Hsp60+/− mice exhibit elevated insulin-independent glucose uptake. Hsp60+/− mice show improved global, but impaired WAT insulin action.
Collapse
|
7
|
Abstract
The inbred mouse strain C57BL/6 has been widely used as a background strain for spontaneous and induced mutations. Developed in the 1930s, the C57BL/6 strain
diverged into two major groups in the 1950s, namely, C57BL/6J and C57BL/6N, and more than 20 substrains have been established from them worldwide. We previously
reported genetic differences among C57BL/6 substrains in 2009 and 2015. Since then, dozens of reports have been published on phenotypic differences in
behavioral, neurological, cardiovascular, and metabolic traits. Substrains need to be chosen according to the purpose of the study because phenotypic
differences might affect the experimental results. In this paper, we review recent reports of phenotypic and genetic differences among C57BL/6 substrains, focus
our attention on the proper use of C57BL/6 and other inbred strains in the era of genome editing, and provide the life science research community wider
knowledge about this subject.
Collapse
Affiliation(s)
- Kazuyuki Mekada
- Department of Zoology, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005, Japan.,Experimental Animal Division, RIKEN BioResource Research Center, 3-1-1 Koyadai, Tsukuba, Ibaraki 305-0074, Japan
| | - Atsushi Yoshiki
- Experimental Animal Division, RIKEN BioResource Research Center, 3-1-1 Koyadai, Tsukuba, Ibaraki 305-0074, Japan
| |
Collapse
|
8
|
Tam WY, Cheung KK. Phenotypic characteristics of commonly used inbred mouse strains. J Mol Med (Berl) 2020; 98:1215-1234. [PMID: 32712726 DOI: 10.1007/s00109-020-01953-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 07/13/2020] [Accepted: 07/16/2020] [Indexed: 12/16/2022]
Abstract
The laboratory mouse is the most commonly used mammalian model for biomedical research. An enormous number of mouse models, such as gene knockout, knockin, and overexpression transgenic mice, have been created over the years. A common practice to maintain a genetically modified mouse line is backcrossing with standard inbred mice over several generations. However, the choice of inbred mouse for backcrossing is critical to phenotypic characterization because phenotypic variabilities are often observed between mice with different genetic backgrounds. In this review, the major features of commonly used inbred mouse lines are discussed. The aim is to provide information for appropriate selection of inbred mouse lines for genetic and behavioral studies.
Collapse
Affiliation(s)
- Wing Yip Tam
- University Research Facility in Behavioral and Systems Neuroscience, The Hong Kong Polytechnic University, Hong Kong, SAR, China
| | - Kwok-Kuen Cheung
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong, SAR, China.
| |
Collapse
|
9
|
Abstract
C57BL/6J and C57BL/6N inbred mice are widely, and often interchangeably, used for stem cell research; yet, these substrains harbor discrete genetic differences that can cause phenotypic disparities. In this issue of Stem Cell Reports, Morales-Hernández et al. identify one particular difference—disruption of Nicotinamide Nucleotide Transhydrogenase (Nnt)—that increases reactive oxygen exposure and impairs hematopoietic progenitor cell function in C57BL/6J, as compared to C57BL/6N, mice.
Collapse
|
10
|
ImmGen report: sexual dimorphism in the immune system transcriptome. Nat Commun 2019; 10:4295. [PMID: 31541153 PMCID: PMC6754408 DOI: 10.1038/s41467-019-12348-6] [Citation(s) in RCA: 129] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 08/29/2019] [Indexed: 11/24/2022] Open
Abstract
Sexual dimorphism in the mammalian immune system is manifested as more frequent and severe infectious diseases in males and, on the other hand, higher rates of autoimmune disease in females, yet insights underlying those differences are still lacking. Here we characterize sex differences in the immune system by RNA and ATAC sequence profiling of untreated and interferon-induced immune cell types in male and female mice. We detect very few differentially expressed genes between male and female immune cells except in macrophages from three different tissues. Accordingly, very few genomic regions display differences in accessibility between sexes. Transcriptional sexual dimorphism in macrophages is mediated by genes of innate immune pathways, and increases after interferon stimulation. Thus, the stronger immune response of females may be due to more activated innate immune pathways prior to pathogen invasion. Sexual dimorphism is observed frequently in immune disorders, but the underlying insights are still unclear. Here the authors analyze transcriptome and epigenome changes induced by interferon in various mouse immune cell types, and find only a restricted set of sexual dimorphism genes in innate immunity and macrophages.
Collapse
|