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Poole RJ, Flames N, Cochella L. Neurogenesis in Caenorhabditis elegans. Genetics 2024:iyae116. [PMID: 39167071 DOI: 10.1093/genetics/iyae116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2024] [Accepted: 06/24/2024] [Indexed: 08/23/2024] Open
Abstract
Animals rely on their nervous systems to process sensory inputs, integrate these with internal signals, and produce behavioral outputs. This is enabled by the highly specialized morphologies and functions of neurons. Neuronal cells share multiple structural and physiological features, but they also come in a large diversity of types or classes that give the nervous system its broad range of functions and plasticity. This diversity, first recognized over a century ago, spurred classification efforts based on morphology, function, and molecular criteria. Caenorhabditis elegans, with its precisely mapped nervous system at the anatomical level, an extensive molecular description of most of its neurons, and its genetic amenability, has been a prime model for understanding how neurons develop and diversify at a mechanistic level. Here, we review the gene regulatory mechanisms driving neurogenesis and the diversification of neuron classes and subclasses in C. elegans. We discuss our current understanding of the specification of neuronal progenitors and their differentiation in terms of the transcription factors involved and ensuing changes in gene expression and chromatin landscape. The central theme that has emerged is that the identity of a neuron is defined by modules of gene batteries that are under control of parallel yet interconnected regulatory mechanisms. We focus on how, to achieve these terminal identities, cells integrate information along their developmental lineages. Moreover, we discuss how neurons are diversified postembryonically in a time-, genetic sex-, and activity-dependent manner. Finally, we discuss how the understanding of neuronal development can provide insights into the evolution of neuronal diversity.
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Affiliation(s)
- Richard J Poole
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Nuria Flames
- Developmental Neurobiology Unit, Instituto de Biomedicina de Valencia IBV-CSIC, Valencia 46012, Spain
| | - Luisa Cochella
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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2
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Fang M, Liu Y, Gao X, Yu J, Tu X, Mo X, Zhu H, Zou Y, Huang C, Fan S. Perillaldehyde alleviates polyQ-induced neurodegeneration through the induction of autophagy and mitochondrial UPR in Caenorhabditis elegans. Biofactors 2024. [PMID: 38990058 DOI: 10.1002/biof.2089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 06/03/2024] [Indexed: 07/12/2024]
Abstract
Huntington's disease (HD) is a fatal neurodegenerative disease associated with autophagy disorder and mitochondrial dysfunction. Here, we identified therapeutic potential of perillaldehyde (PAE), a monoterpene compound obtained from Perilla frutescens (L.) Britt., in the Caenorhabditis elegans (C. elegans) model of HD, which included lifespan extension, healthspan improvement, decrease in polyglutamine (polyQ) aggregation, and preservation of mitochondrial network. Further analyses indicated that PAE was able to induce autophagy and mitochondrial unfolded protein reaction (UPRmt) activation and positively regulated expression of associated genes. In lgg-1 RNAi C. elegans or C. elegans with UPRmt-related genes knockdown, the effects of PAE treatment on polyQ aggregation or rescue polyQ-induced toxicity were attenuated, suggesting that its neuroprotective activity depended on autophagy and UPRmt. Moreover, we found that pharmacological and genetic activation of UPRmt generally protected C. elegans from polyQ-induced cytotoxicity. Finally, PAE promoted serotonin synthesis by upregulating expression of TPH-1, and serotonin synthesis and neurosecretion were required for PAE-mediated UPRmt activation and its neuroprotective activity. In conclusion, PAE is a potential therapy for polyQ-related diseases including HD, which is dependent on autophagy and cell-non-autonomous UPRmt activation.
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Affiliation(s)
- Minglv Fang
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Ying Liu
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Xiaoyan Gao
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Jing Yu
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Xiaohui Tu
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Xueying Mo
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Huanhu Zhu
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Yan Zou
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Cheng Huang
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Shengjie Fan
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
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3
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Ji H, Chen D, Fang-Yen C. Segmentation-free measurement of locomotor frequency in Caenorhabditis elegans using image invariants. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.16.575892. [PMID: 38293059 PMCID: PMC10827210 DOI: 10.1101/2024.01.16.575892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
An animal's locomotor rate is an important indicator of its motility. In studies of the nematode C. elegans, assays of the frequency of body bending waves have often been used to discern the effects of mutations, drugs, or aging. Traditional manual methods for measuring locomotor frequency are low in throughput and subject to human error. Most current automated methods depend on image segmentation, which requires high image quality and is prone to errors. Here, we describe an algorithm for automated estimation of C. elegans locomotor frequency using image invariants, i.e., shape-based parameters that are independent of object translation, rotation, and scaling. For each video frame, the method calculates a combination of 8 Hu's moment invariants and a set of Maximally Stable Extremal Regions (MSER) invariants. The algorithm then calculates the locomotor frequency by computing the autocorrelation of the time sequence of the invariant ensemble. Results of our method show excellent agreement with manual or segmentation-based results over a wide range of frequencies. We show that compared to a segmentation-based method that analyzes a worm's shape and a method based on video covariance, our technique is more robust to low image quality and background noise. We demonstrate the system's capabilities by testing the effects of serotonin and serotonin pathway mutations on C. elegans locomotor frequency.
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4
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Abraham E, Athapaththu AMGK, Atanasova KR, Chen QY, Corcoran TJ, Piloto J, Wu CW, Ratnayake R, Luesch H, Choe KP. Chemical Genetics in C. elegans Identifies Anticancer Mycotoxins Chaetocin and Chetomin as Potent Inducers of a Nuclear Metal Homeostasis Response. ACS Chem Biol 2024; 19:1180-1193. [PMID: 38652683 PMCID: PMC11102292 DOI: 10.1021/acschembio.4c00131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
C. elegans numr-1/2 (nuclear-localized metal-responsive) is an identical gene pair encoding a nuclear protein previously shown to be activated by cadmium and disruption of the integrator RNA metabolism complex. We took a chemical genetic approach to further characterize regulation of this novel metal response by screening 41,716 compounds and extracts for numr-1p::GFP activation. The most potent activator was chaetocin, a fungal 3,6-epidithiodiketopiperazine (ETP) with promising anticancer activity. Chaetocin activates numr-1/2 strongly in the alimentary canal but is distinct from metal exposure, because it represses canonical cadmium-responsive metallothionine genes. Chaetocin has diverse targets in cancer cells including thioredoxin reductase, histone lysine methyltransferase, and acetyltransferase p300/CBP; further work is needed to identify the mechanism in C. elegans as genetic disruption and RNAi screening of homologues did not induce numr-1/2 in the alimentary canal and chaetocin did not affect markers of integrator dysfunction. We demonstrate that disulfides in chaetocin and chetomin, a dimeric ETP analog, are required to induce numr-1/2. ETP monomer gliotoxin, despite possessing a disulfide linkage, had almost no effect on numr-1/2, suggesting a dimer requirement. Chetomin inhibits C. elegans growth at low micromolar levels, and loss of numr-1/2 increases sensitivity; C. elegans and Chaetomiaceae fungi inhabit similar environments raising the possibility that numr-1/2 functions as a defense mechanism. There is no direct orthologue of numr-1/2 in humans, but RNaseq suggests that chaetocin affects expression of cellular processes linked to stress response and metal homeostasis in colorectal cancer cells. Our results reveal interactions between metal response gene regulation and ETPs and identify a potential mechanism of resistance to this versatile class of preclinical compounds.
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Affiliation(s)
- Elijah Abraham
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
| | | | - Kalina R. Atanasova
- Department of Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
- Center for Natural Products, Drug Discovery and Development, University of Florida, Gainesville, Florida 32610, United States
| | - Qi-Yin Chen
- Department of Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
- Center for Natural Products, Drug Discovery and Development, University of Florida, Gainesville, Florida 32610, United States
| | - Taylor J. Corcoran
- Department of Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
- Center for Natural Products, Drug Discovery and Development, University of Florida, Gainesville, Florida 32610, United States
| | - Juan Piloto
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
| | - Cheng-Wei Wu
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, S&N 5B4 Canada
| | - Ranjala Ratnayake
- Department of Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
- Center for Natural Products, Drug Discovery and Development, University of Florida, Gainesville, Florida 32610, United States
| | - Hendrik Luesch
- Department of Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
- Center for Natural Products, Drug Discovery and Development, University of Florida, Gainesville, Florida 32610, United States
| | - Keith P. Choe
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
- Center for Natural Products, Drug Discovery and Development, University of Florida, Gainesville, Florida 32610, United States
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
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Mignerot L, Gimond C, Bolelli L, Bouleau C, Sandjak A, Boulin T, Braendle C. Natural variation in the Caenorhabditis elegans egg-laying circuit modulates an intergenerational fitness trade-off. eLife 2024; 12:RP88253. [PMID: 38564369 PMCID: PMC10987095 DOI: 10.7554/elife.88253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024] Open
Abstract
Evolutionary transitions from egg laying (oviparity) to live birth (viviparity) are common across various taxa. Many species also exhibit genetic variation in egg-laying mode or display an intermediate mode with laid eggs containing embryos at various stages of development. Understanding the mechanistic basis and fitness consequences of such variation remains experimentally challenging. Here, we report highly variable intra-uterine egg retention across 316 Caenorhabditis elegans wild strains, some exhibiting strong retention, followed by internal hatching. We identify multiple evolutionary origins of such phenotypic extremes and pinpoint underlying candidate loci. Behavioral analysis and genetic manipulation indicates that this variation arises from genetic differences in the neuromodulatory architecture of the egg-laying circuitry. We provide experimental evidence that while strong egg retention can decrease maternal fitness due to in utero hatching, it may enhance offspring protection and confer a competitive advantage. Therefore, natural variation in C. elegans egg-laying behaviour can alter an apparent trade-off between different fitness components across generations. Our findings highlight underappreciated diversity in C. elegans egg-laying behavior and shed light on its fitness consequences. This behavioral variation offers a promising model to elucidate the molecular changes in a simple neural circuit underlying evolutionary shifts between alternative egg-laying modes in invertebrates.
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Affiliation(s)
| | | | | | | | - Asma Sandjak
- Université Côte d’Azur, CNRS, Inserm, IBVNiceFrance
| | - Thomas Boulin
- Institut NeuroMyoGène, CNRS, Inserm, Université de LyonLyonFrance
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6
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Ji H, Chen D, Fang-Yen C. Automated multimodal imaging of Caenorhabditis elegans behavior in multi-well plates. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.09.579675. [PMID: 38405855 PMCID: PMC10888940 DOI: 10.1101/2024.02.09.579675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Large-scale assays of behavior in model organisms play an important role in genetic screens, drug testing, and the elucidation of gene-behavior relationships. We have developed an automated, high-throughput imaging and analysis method for assaying behaviors of the nematode C. elegans . We use high-resolution optical imaging to longitudinally record the behaviors of 96 animals at a time in multi-well plates, and computer vision software to quantify the animals' locomotor activity, behavioral states, and egg laying events. To demonstrate the capabilities of our system we used it to examine the role of serotonin in C. elegans behavior. We found that egg-laying events are preceded by a period of reduced locomotion, and that this decline in movement requires serotonin signaling. In addition, we identified novel roles of serotonin receptors SER-1 and SER-7 in regulating the effects of serotonin on egg laying across roaming, dwelling, and quiescent locomotor states. Our system will be useful for performing genetic or chemical screens for modulators of behavior.
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7
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Gupta S, Dinesh S, Sharma S. Bridging the Mind and Gut: Uncovering the Intricacies of Neurotransmitters, Neuropeptides, and their Influence on Neuropsychiatric Disorders. Cent Nerv Syst Agents Med Chem 2024; 24:2-21. [PMID: 38265387 DOI: 10.2174/0118715249271548231115071021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 08/31/2023] [Accepted: 10/04/2023] [Indexed: 01/25/2024]
Abstract
BACKGROUND The gut-brain axis (GBA) is a bidirectional signaling channel that facilitates communication between the gastrointestinal tract and the brain. Recent research on the gut-brain axis demonstrates that this connection enables the brain to influence gut function, which in turn influences the brain and its cognitive functioning. It is well established that malfunctioning of this axis adversely affects both systems' ability to operate effectively. OBJECTIVE Dysfunctions in the GBA have been associated with disorders of gut motility and permeability, intestinal inflammation, indigestion, constipation, diarrhea, IBS, and IBD, as well as neuropsychiatric and neurodegenerative disorders like depression, anxiety, schizophrenia, autism, Alzheimer's, and Parkinson's disease. Multiple research initiatives have shown that the gut microbiota, in particular, plays a crucial role in the GBA by participating in the regulation of a number of key neurochemicals that are known to have significant effects on the mental and physical well-being of an individual. METHODS Several studies have investigated the relationship between neuropsychiatric disorders and imbalances or disturbances in the metabolism of neurochemicals, often leading to concomitant gastrointestinal issues and modifications in gut flora composition. The interaction between neurological diseases and gut microbiota has been a focal point within this research. The novel therapeutic interventions in neuropsychiatric conditions involving interventions such as probiotics, prebiotics, and dietary modifications are outlined in this review. RESULTS The findings of multiple studies carried out on mice show that modulating and monitoring gut microbiota can help treat symptoms of such diseases, which raises the possibility of the use of probiotics, prebiotics, and even dietary changes as part of a new treatment strategy for neuropsychiatric disorders and their symptoms. CONCLUSION The bidirectional communication between the gut and the brain through the gut-brain axis has revealed profound implications for both gastrointestinal and neurological health. Malfunctions in this axis have been connected to a range of disorders affecting gut function as well as cognitive and neuropsychiatric well-being. The emerging understanding of the role of gut microbiota in regulating key neurochemicals opens up possibilities for novel treatment approaches for conditions like depression, anxiety, and neurodegenerative diseases.
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Affiliation(s)
- Saumya Gupta
- Department of Bioinformatics, BioNome, Bengaluru, India
| | - Susha Dinesh
- Department of Bioinformatics, BioNome, Bengaluru, India
| | - Sameer Sharma
- Department of Bioinformatics, BioNome, Bengaluru, India
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8
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Beydoun S, Kitto ES, Wang E, Huang S, Leiser SF. Methodology to Metabolically Inactivate Bacteria for Caenorhabditis elegans Research. J Vis Exp 2023:10.3791/65775. [PMID: 37578251 PMCID: PMC11064985 DOI: 10.3791/65775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023] Open
Abstract
Caenorhabditis elegans is a common model organism for research in genetics, development, aging, metabolism, and behavior. Because C. elegans consume a diet of live bacteria, the metabolic activity of their food source can confound experiments looking for the direct effects of various interventions on the worm. To avoid the confounding effects of bacterial metabolism, C. elegans researchers have used multiple methods to metabolically inactivate bacteria, including ultraviolet (UV)-irradiation, heat-killing, and antibiotics. UV treatment is relatively low-throughput and cannot be used in liquid culture because each plate must be examined for successful bacterial killing. A second treatment method, heat-killing, negatively affects the texture and nutritional quality of the bacteria, leading to the developmental arrest of C. elegans. Finally, antibiotic treatment can directly alter C. elegans physiology in addition to preventing bacterial growth. This manuscript describes an alternative method to metabolically inactivate bacteria using paraformaldehyde (PFA). PFA treatment cross-links proteins within bacterial cells to prevent metabolic activity while preserving cellular structure and nutritional content. This method is high-throughput and can be used in liquid culture or solid plates, as testing one plate of PFA-treated bacteria for growth validates the whole batch. Metabolic inactivation through PFA treatment can be used to eliminate the confounding effects of bacterial metabolism on studies of drug or metabolite supplementation, stress resistance, metabolomics, and behavior in C. elegans.
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Affiliation(s)
- Safa Beydoun
- Molecular and Integrative Physiology Department, University of Michigan, Ann Arbor
| | - Elizabeth S Kitto
- Molecular and Integrative Physiology Department, University of Michigan, Ann Arbor
| | - Emily Wang
- Molecular and Integrative Physiology Department, University of Michigan, Ann Arbor
| | - Shijiao Huang
- Molecular and Integrative Physiology Department, University of Michigan, Ann Arbor
| | - Scott F Leiser
- Molecular and Integrative Physiology Department, University of Michigan, Ann Arbor; Department of Internal Medicine, University of Michigan, Ann Arbor;
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Vickery WM, Wood HB, Orlando JD, Singh J, Deng C, Li L, Zhou JY, Lanni F, Porter AW, Sydlik SA. Environmental and health impacts of functional graphenic materials and their ultrasonically altered products. NANOIMPACT 2023; 31:100471. [PMID: 37315844 DOI: 10.1016/j.impact.2023.100471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 06/16/2023]
Abstract
Graphenic materials have excited the scientific community due to their exciting mechanical, thermal, and optoelectronic properties for a potential range of applications. Graphene and graphene derivatives have demonstrated application in areas stretching from composites to medicine; however, the environmental and health impacts of these materials have not been sufficiently characterized. Graphene oxide (GO) is one of the most widely used graphenic derivatives due to a relatively easy and scalable synthesis, and the ability to tailor the oxygen containing functional groups through further chemical modification. In this paper, ecological and health impacts of fresh and ultrasonically altered functional graphenic materials (FGMs) were investigated. Model organisms, specifically Escherichia coli, Bacillus subtilis, and Caenorhabditis elegans, were used to assess the consequences of environmental exposure to fresh and ultrasonically altered FGMs. FGMs were selected to evaluate the environmental effects of aggregation state, degree of oxidation, charge, and ultrasonication. The major findings indicate that bacterial cell viability, nematode fertility, and nematode movement were largely unaffected, suggesting that a wide variety of FGMs may not pose significant health and environmental risks.
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Affiliation(s)
- Walker M Vickery
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, United States
| | - Hunter B Wood
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, United States
| | - Jason D Orlando
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, United States
| | - Juhi Singh
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, United States
| | - Chenyun Deng
- Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, United States
| | - Li Li
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, United States
| | - Jing-Yi Zhou
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, United States
| | - Frederick Lanni
- Department of Biological Sciences, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, United States
| | - Aidan W Porter
- Department of Pediatrics, Nephrology Division, University of Pittsburgh School of Medicine, 5th and Ruskin Ave, Pittsburg, PA 15260, United States; Division of Nephrology, Children's Hospital of Pittsburgh, 4401 Penn Ave, Pittsburgh, PA 15224, United States
| | - Stefanie A Sydlik
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, United States; Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, United States.
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10
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Bates K, Le KN, Lu H. Deep learning for robust and flexible tracking in behavioral studies for C. elegans. PLoS Comput Biol 2022; 18:e1009942. [PMID: 35395006 PMCID: PMC9020731 DOI: 10.1371/journal.pcbi.1009942] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 04/20/2022] [Accepted: 02/21/2022] [Indexed: 12/02/2022] Open
Abstract
Robust and accurate behavioral tracking is essential for ethological studies. Common methods for tracking and extracting behavior rely on user adjusted heuristics that can significantly vary across different individuals, environments, and experimental conditions. As a result, they are difficult to implement in large-scale behavioral studies with complex, heterogenous environmental conditions. Recently developed deep-learning methods for object recognition such as Faster R-CNN have advantages in their speed, accuracy, and robustness. Here, we show that Faster R-CNN can be employed for identification and detection of Caenorhabditis elegans in a variety of life stages in complex environments. We applied the algorithm to track animal speeds during development, fecundity rates and spatial distribution in reproductive adults, and behavioral decline in aging populations. By doing so, we demonstrate the flexibility, speed, and scalability of Faster R-CNN across a variety of experimental conditions, illustrating its generalized use for future large-scale behavioral studies.
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Affiliation(s)
- Kathleen Bates
- Interdisciplinary Program in Bioengineering, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Kim N. Le
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, United States of America
| | - Hang Lu
- Interdisciplinary Program in Bioengineering, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, United States of America
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11
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Cheng J, Li W, Wang Y, Cao Q, Ni Y, Zhang W, Guo J, Chen B, Zang Y, Zhu Y. Electroacupuncture modulates the intestinal microecology to improve intestinal motility in spinal cord injury rats. Microb Biotechnol 2021; 15:862-873. [PMID: 34797954 PMCID: PMC8913878 DOI: 10.1111/1751-7915.13968] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 10/29/2021] [Accepted: 10/30/2021] [Indexed: 12/14/2022] Open
Abstract
Spinal cord injury (SCI) is a disease involving gastrointestinal disorders. The underlying mechanisms of the potential protective effects of electroacupuncture (EA) and 5-hydroxytryptamine (5-HT) system on SCI remain unknown. We investigated whether EA improves gut microbial dysbiosis in SCI and regulates the 5-HT system. 16S rDNA gene sequencing was applied to investigate alterations in the gut microbiome of the rats. Faecal metabolites and the expression of the 5-HT system were detected. EA and faecal microbiota transplantation (FMT) treatment facilitated intestinal transmission functional recovery and restored the colon morphology of SCI rats. The composition of the intestinal microbiota, including numbers of phylum Proteobacteria, class Clostridia, order Bacteroidales, and genus Dorea, were amplified in SCI rats, and EA and FMT significantly reshaped the intestinal microbiota. SCI resulted in disturbed metabolic conditions in rats, and the EA and FMT group showed increased amounts of catechin compared with SCI rats. SCI inhibited 5-HT system expression in the colon, which was significantly reversed by EA and FMT treatment. Therefore, EA may ameliorate SCI by modulating microbiota and metabolites and regulate the 5-HT system. Our study provides new insights into the pathogenesis and therapy of SCI from the perspective of microbiota and 5-HT regulation.
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Affiliation(s)
- Jie Cheng
- Nanjing University of Chinese Medicine, Nanjing, China
| | - Weimin Li
- The Second Affiliated Hospital of Hainan Medical University, Haikou, China
| | - Ying Wang
- The Ninth People's Hospital of Wuxi affiliated to Soochow University, Wuxi, China.,Department of Kinesiology, Shanghai University of Sport, Shanghai, China
| | - Qing Cao
- Department of Kinesiology, Shanghai University of Sport, Shanghai, China.,Zigong Forth People's Hospital, Zigong, China
| | - Ying Ni
- Nanjing University of Chinese Medicine, Nanjing, China
| | - Wenyi Zhang
- Zhongshan Rehabilitation Hospital Affiliated to Jiangsu Provincial People's Hospital, Nanjing, China
| | - Jiabao Guo
- The Second Clinical Medical School, Xuzhou Medical University, Xuzhou, China
| | - Binglin Chen
- The Second Clinical Medical School, Xuzhou Medical University, Xuzhou, China
| | - Yaning Zang
- Department of Kinesiology, Shanghai University of Sport, Shanghai, China
| | - Yi Zhu
- The Second Affiliated Hospital of Hainan Medical University, Haikou, China.,The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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12
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Pujol N, Ewbank JJ. C. elegans: out on an evolutionary limb. Immunogenetics 2021; 74:63-73. [PMID: 34761293 DOI: 10.1007/s00251-021-01231-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 10/22/2021] [Indexed: 12/18/2022]
Abstract
The natural environment of the free-living nematode Caenorhabditis elegans is rich in pathogenic microbes. There is now ample evidence to indicate that these pathogens exert a strong selection pressure on C. elegans, and have shaped its genome, physiology, and behaviour. In this short review, we concentrate on how C. elegans stands out from other animals in terms of its immune repertoire and innate immune signalling pathways. We discuss how C. elegans often detects pathogens because of their effects on essential cellular processes, or organelle integrity, in addition to direct microbial recognition. We illustrate the extensive molecular plasticity that is characteristic of immune defences in C. elegans and highlight some remarkable instances of lineage-specific innovation in innate immune mechanisms.
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Affiliation(s)
- Nathalie Pujol
- Aix Marseille Univ, CNRS, INSERM, CIML, Turing Centre for Living Systems, Marseille, France.
| | - Jonathan J Ewbank
- Aix Marseille Univ, CNRS, INSERM, CIML, Turing Centre for Living Systems, Marseille, France
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13
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Layunta E, Buey B, Mesonero JE, Latorre E. Crosstalk Between Intestinal Serotonergic System and Pattern Recognition Receptors on the Microbiota-Gut-Brain Axis. Front Endocrinol (Lausanne) 2021; 12:748254. [PMID: 34819919 PMCID: PMC8607755 DOI: 10.3389/fendo.2021.748254] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 10/05/2021] [Indexed: 12/12/2022] Open
Abstract
Disruption of the microbiota-gut-brain axis results in a wide range of pathologies that are affected, from the brain to the intestine. Gut hormones released by enteroendocrine cells to the gastrointestinal (GI) tract are important signaling molecules within this axis. In the search for the language that allows microbiota to communicate with the gut and the brain, serotonin seems to be the most important mediator. In recent years, serotonin has emerged as a key neurotransmitter in the gut-brain axis because it largely contributes to both GI and brain physiology. In addition, intestinal microbiota are crucial in serotonin signaling, which gives more relevance to the role of the serotonin as an important mediator in microbiota-host interactions. Despite the numerous investigations focused on the gut-brain axis and the pathologies associated, little is known regarding how serotonin can mediate in the microbiota-gut-brain axis. In this review, we will mainly discuss serotonergic system modulation by microbiota as a pathway of communication between intestinal microbes and the body on the microbiota-gut-brain axis, and we explore novel therapeutic approaches for GI diseases and mental disorders.
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Affiliation(s)
- Elena Layunta
- Institute of Biomedicine, Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
- Instituto de Investigación Sanitaria de Aragón (IIS Aragón), Zaragoza, Spain
| | - Berta Buey
- Departamento de Farmacología, Fisiología y Medicina Legal y Forense, Universidad de Zaragoza, Zaragoza, Spain
| | - Jose Emilio Mesonero
- Instituto de Investigación Sanitaria de Aragón (IIS Aragón), Zaragoza, Spain
- Departamento de Farmacología, Fisiología y Medicina Legal y Forense, Universidad de Zaragoza, Zaragoza, Spain
- Instituto Agroalimentario de Aragón—IA2 (Universidad de Zaragoza–CITA), Zaragoza, Spain
| | - Eva Latorre
- Instituto de Investigación Sanitaria de Aragón (IIS Aragón), Zaragoza, Spain
- Instituto Agroalimentario de Aragón—IA2 (Universidad de Zaragoza–CITA), Zaragoza, Spain
- Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, Zaragoza, Spain
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