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Chen LA, Boyle K. The Role of the Gut Microbiome in Health and Disease in the Elderly. Curr Gastroenterol Rep 2024:10.1007/s11894-024-00932-w. [PMID: 38642272 DOI: 10.1007/s11894-024-00932-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/05/2024] [Indexed: 04/22/2024]
Abstract
PURPOSE OF REVIEW Growing evidence supports the contribution of age in the composition and function of the gut microbiome, with specific findings associated with health in old age and longevity. RECENT FINDINGS Current studies have associated certain microbiota, such as Butyricimonas, Akkermansia, and Odoribacter, with healthy aging and the ability to survive into extreme old age. Furthermore, emerging clinical and pre-clinical research have shown promising mechanisms for restoring a healthy microbiome in elderly populations through various interventions such as fecal microbiota transplant (FMT), dietary interventions, and exercise programs. Despite several conceptually exciting interventional studies, the field of microbiome research in the elderly remains limited. Specifically, large longitudinal studies are needed to better understand causative relationships between the microbiome and healthy aging. Additionally, individualized approaches to microbiome interventions based on patients' co-morbidities and the underlying functional capacity of their microbiomes are needed to achieve optimal results.
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Affiliation(s)
- Lea Ann Chen
- Division of Gastroenterology and Hepatology, Department of Medicine, Rutgers, New Brunswick, NJ, USA.
| | - Kaitlyn Boyle
- Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, USA
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2
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Zhang T, Gao G, Kwok LY, Sun Z. Gut microbiome-targeted therapies for Alzheimer's disease. Gut Microbes 2023; 15:2271613. [PMID: 37934614 PMCID: PMC10631445 DOI: 10.1080/19490976.2023.2271613] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 10/12/2023] [Indexed: 11/09/2023] Open
Abstract
The advent of high-throughput 'omics' technologies has improved our knowledge of gut microbiome in human health and disease, including Alzheimer's disease (AD), a neurodegenerative disorder. Frequent bidirectional communications and mutual regulation exist between the gastrointestinal tract and the central nervous system through the gut-brain axis. A large body of research has reported a close association between the gut microbiota and AD development, and restoring a healthy gut microbiota may curb or even improve AD symptoms and progression. Thus, modulation of the gut microbiota has become a novel paradigm for clinical management of AD, and emerging effort has focused on developing potential novel strategies for preventing and/or treating the disease. In this review, we provide an overview of the connection and causal relationship between gut dysbiosis and AD, the mechanisms of gut microbiota in driving AD progression, and the successes and challenges of implementing available gut microbiome-targeted therapies (including probiotics, prebiotics, synbiotics, postbiotics, and fecal microbiota transplantation) in preventive and/or therapeutic preclinical and clinical intervention studies of AD. Finally, we discuss the future directions in this field.
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Affiliation(s)
- Tao Zhang
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, China
- Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, China
- Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering, Inner Mongolia Agricultural University, Hohhot, China
| | - Guangqi Gao
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, China
- Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, China
- Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering, Inner Mongolia Agricultural University, Hohhot, China
| | - Lai-Yu Kwok
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, China
- Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, China
- Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering, Inner Mongolia Agricultural University, Hohhot, China
| | - Zhihong Sun
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, China
- Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, China
- Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering, Inner Mongolia Agricultural University, Hohhot, China
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3
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Kapphan LM, Nguyen VTT, Heinrich I, Tüscher O, Passauer P, Schwiertz A, Endres K. Comparison of Frailty and Chronological Age as Determinants of the Murine Gut Microbiota in an Alzheimer's Disease Mouse Model. Microorganisms 2023; 11:2856. [PMID: 38138000 PMCID: PMC10745811 DOI: 10.3390/microorganisms11122856] [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: 10/12/2023] [Revised: 11/15/2023] [Accepted: 11/21/2023] [Indexed: 12/24/2023] Open
Abstract
The ageing of an organism is associated with certain features of functional decline that can be assessed at the cellular level (e.g., reduced telomere length, loss of proteostasis, etc.), but also at the organismic level. Frailty is an independent syndrome that involves increased multidimensional age-related deficits, heightens vulnerability to stressors, and involves physical deficits in mainly the locomotor/muscular capacity, but also in physical appearance and cognition. For sporadic Alzheimer's disease, age per se is one of the most relevant risk factors, but frailty has also been associated with this disease. Therefore, we aimed to answer the two following questions within a cross-sectional study: (1) do Alzheimer's model mice show increased frailty, and (2) what changes of the microbiota occur concerning chronological age or frailty? Indeed, aged 5xFAD mice showed increased frailty compared to wild type littermates. In addition, 5xFAD mice had significantly lower quantities of Bacteroides spp. when only considering frailty, and lower levels of Bacteroidetes in terms of both frailty and chronological age compared to their wild type littermates. Thus, the quality of ageing-as assessed by frailty measures-should be taken into account to unravel potential changes in the gut microbial community in Alzheimer's disease.
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Affiliation(s)
- Laura Malina Kapphan
- Department of Psychiatry and Psychotherapy, University Medical Center Johannes Gutenberg-University Mainz, 55131 Mainz, Germany; (L.M.K.); (V.T.T.N.); (I.H.); (O.T.)
| | - Vu Thu Thuy Nguyen
- Department of Psychiatry and Psychotherapy, University Medical Center Johannes Gutenberg-University Mainz, 55131 Mainz, Germany; (L.M.K.); (V.T.T.N.); (I.H.); (O.T.)
| | - Isabel Heinrich
- Department of Psychiatry and Psychotherapy, University Medical Center Johannes Gutenberg-University Mainz, 55131 Mainz, Germany; (L.M.K.); (V.T.T.N.); (I.H.); (O.T.)
| | - Oliver Tüscher
- Department of Psychiatry and Psychotherapy, University Medical Center Johannes Gutenberg-University Mainz, 55131 Mainz, Germany; (L.M.K.); (V.T.T.N.); (I.H.); (O.T.)
| | - Pamela Passauer
- MVZ Institut für Mikroökologie GmbH, 35745 Herborn, Germany; (P.P.); (A.S.)
| | - Andreas Schwiertz
- MVZ Institut für Mikroökologie GmbH, 35745 Herborn, Germany; (P.P.); (A.S.)
| | - Kristina Endres
- Department of Psychiatry and Psychotherapy, University Medical Center Johannes Gutenberg-University Mainz, 55131 Mainz, Germany; (L.M.K.); (V.T.T.N.); (I.H.); (O.T.)
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Endres K, Friedland K. Talk to Me-Interplay between Mitochondria and Microbiota in Aging. Int J Mol Sci 2023; 24:10818. [PMID: 37445995 DOI: 10.3390/ijms241310818] [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: 05/26/2023] [Revised: 06/21/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023] Open
Abstract
The existence of mitochondria in eukaryotic host cells as a remnant of former microbial organisms has been widely accepted, as has their fundamental role in several diseases and physiological aging. In recent years, it has become clear that the health, aging, and life span of multicellular hosts are also highly dependent on the still-residing microbiota, e.g., those within the intestinal system. Due to the common evolutionary origin of mitochondria and these microbial commensals, it is intriguing to investigate if there might be a crosstalk based on preserved common properties. In the light of rising knowledge on the gut-brain axis, such crosstalk might severely affect brain homeostasis in aging, as neuronal tissue has a high energy demand and low tolerance for according functional decline. In this review, we summarize what is known about the impact of both mitochondria and the microbiome on the host's aging process and what is known about the aging of both entities. For a long time, bacteria were assumed to be immortal; however, recent evidence indicates their aging and similar observations have been made for mitochondria. Finally, we present pathways by which mitochondria are affected by microbiota and give information about therapeutic anti-aging approaches that are based on current knowledge.
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Affiliation(s)
- Kristina Endres
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg-University, 55131 Mainz, Germany
| | - Kristina Friedland
- Department of Pharmacology and Toxicology, Institute for Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University, 55128 Mainz, Germany
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Chandra S, Sisodia SS, Vassar RJ. The gut microbiome in Alzheimer's disease: what we know and what remains to be explored. Mol Neurodegener 2023; 18:9. [PMID: 36721148 PMCID: PMC9889249 DOI: 10.1186/s13024-023-00595-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 01/06/2023] [Indexed: 02/02/2023] Open
Abstract
Alzheimer's disease (AD), the most common cause of dementia, results in a sustained decline in cognition. There are currently few effective disease modifying therapies for AD, but insights into the mechanisms that mediate the onset and progression of disease may lead to new, effective therapeutic strategies. Amyloid beta oligomers and plaques, tau aggregates, and neuroinflammation play a critical role in neurodegeneration and impact clinical AD progression. The upstream modulators of these pathological features have not been fully clarified, but recent evidence indicates that the gut microbiome (GMB) may have an influence on these features and therefore may influence AD progression in human patients. In this review, we summarize studies that have identified alterations in the GMB that correlate with pathophysiology in AD patients and AD mouse models. Additionally, we discuss findings with GMB manipulations in AD models and potential GMB-targeted therapeutics for AD. Lastly, we discuss diet, sleep, and exercise as potential modifiers of the relationship between the GMB and AD and conclude with future directions and recommendations for further studies of this topic.
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Affiliation(s)
- Sidhanth Chandra
- grid.16753.360000 0001 2299 3507Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA ,grid.16753.360000 0001 2299 3507Medical Scientist Training Program, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Sangram S. Sisodia
- grid.170205.10000 0004 1936 7822Department of Neurobiology, University of Chicago, Chicago, IL 60637 USA
| | - Robert J. Vassar
- grid.16753.360000 0001 2299 3507Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
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Vasiliu O. Is fecal microbiota transplantation a useful therapeutic intervention for psychiatric disorders? A narrative review of clinical and preclinical evidence. Curr Med Res Opin 2023; 39:161-177. [PMID: 36094098 DOI: 10.1080/03007995.2022.2124071] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The therapeutic management of psychiatric disorders is currently confronted with a critical need to find new therapeutic interventions due to the high rates of non-responsivity or low responsivity in the key pathologies, e.g. schizophrenia spectrum disorders, alcohol use disorders, or major depressive disorder. The modulation of intestinal microbiota has been explored in various organic and psychiatric dysfunctions, with different degrees of success. However, this type of intervention may represent a helpful add-on at a conceptual level since it does not associate negative pharmacokinetics interactions, significant adverse events, or risk for non-adherence in the long term. Oral administration of pre-, pro-, or synbiotics, and especially the treatment with fecal microbiota transplantation (FMT), are methods still in their early research phase for patients with psychiatric disorders, therefore an exploration of data regarding the potential benefits and adverse events of FMT was considered necessary. In order to accomplish this purpose, the available results of research dedicated to each category of psychiatric disorders, starting with depressive and anxiety disorders, continuing with schizophrenia, substance use disorders, and finishing with disorders diagnosed during childhood, were presented in this paper. Seven clinical trials, 16 preclinical studies, three meta-analyses/systematic reviews, and six case reports, all of these representing ten distinct categories of psychiatric disorders or manifestations, have been reviewed. Mood disorders, anxiety disorders, and alcohol dependence have been the most extensively investigated clinical entities from the FMT efficacy and tolerability perspective, and reviewed data are generally promising. Based on the current status of research, FMT may be considered a helpful intervention in specific psychiatric pathologies. Still, this review showed that most of the information is derived from entirely preclinical studies. Therefore, clinical trials with sound methodology and more participants are needed to clarify FMT's benefits and risks in psychiatric disorders.
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Affiliation(s)
- Octavian Vasiliu
- Spitalul Universitar de Urgenţă Militar Central Dr Carol Davila Ringgold standard institution, Bucuresti, Romania
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7
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Yelleswarapu NK, Masino M, Henderson S, Fernandes R, Swain G, Galligan JJ, Xu H. 5xFAD mice do not have myenteric amyloidosis, dysregulation of neuromuscular transmission or gastrointestinal dysmotility. Neurogastroenterol Motil 2022; 34:e14439. [PMID: 36458522 PMCID: PMC9718934 DOI: 10.1111/nmo.14439] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 04/29/2022] [Accepted: 07/18/2022] [Indexed: 02/08/2023]
Abstract
BACKGROUND Alterations in gastrointestinal (GI) function and the gut-brain axis are associated with progression and pathology of Alzheimer's Disease (AD). Studies in AD animal models show that changes in the gut microbiome and inflammatory markers can contribute to AD development in the central nervous system (CNS). Amyloid-beta (Aβ) accumulation is a major AD pathology causing synaptic dysfunction and neuronal death. Current knowledge of the pathophysiology of AD in enteric neurons is limited, and whether Aβ accumulation directly disrupts enteric neuron function is unknown. METHODS In 6-month-old 5xFAD (transgenic AD) and wildtype (WT) male and female mice, GI function was assessed by colonic transit in vivo; propulsive motility and GI smooth muscle contractions ex vivo; electrochemical detection of enteric nitric oxide release in vitro, and changes in myenteric neuromuscular transmission using smooth muscle intracellular recordings. Expression of Aβ in the brain and colonic myenteric plexus in these mice was determined by immunohistochemistry staining and ELISA assay. KEY RESULTS At 6 months, 5xFAD mice did not show significant changes in GI motility or synaptic neurotransmission in the small intestine or colon. 5xFAD mice, but not WT mice, showed abundant Aβ accumulation in the brain. Aβ accumulation was undetectable in the colonic myenteric plexus of 5xFAD mice. CONCLUSIONS 5xFAD AD mice are not a robust model to study amyloidosis in the gut as these mice do not mimic myenteric neuronal dysfunction in AD patients with GI dysmotility. An AD animal model with enteric amyloidosis is required for further study.
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Affiliation(s)
| | - Marlene Masino
- The Neuroscience ProgramMichigan State UniversityEast LansingMichiganUSA
| | - Skye Henderson
- Department of ChemistryMichigan State UniversityEast LansingMichiganUSA
| | - Roxanne Fernandes
- Department of Pharmacology & ToxicologyMichigan State UniversityEast LansingMichiganUSA
| | - Greg Swain
- The Neuroscience ProgramMichigan State UniversityEast LansingMichiganUSA
- Department of ChemistryMichigan State UniversityEast LansingMichiganUSA
| | - James J. Galligan
- The Neuroscience ProgramMichigan State UniversityEast LansingMichiganUSA
- Department of Pharmacology & ToxicologyMichigan State UniversityEast LansingMichiganUSA
| | - Hui Xu
- The Neuroscience ProgramMichigan State UniversityEast LansingMichiganUSA
- Department of Pharmacology & ToxicologyMichigan State UniversityEast LansingMichiganUSA
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8
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Cheng X, Tan Y, Li H, Huang J, Zhao D, Zhang Z, Yi M, Zhu L, Hui S, Yang J, Peng W. Fecal 16S rRNA sequencing and multi-compartment metabolomics revealed gut microbiota and metabolites interactions in APP/PS1 mice. Comput Biol Med 2022; 151:106312. [PMID: 36417828 DOI: 10.1016/j.compbiomed.2022.106312] [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: 09/13/2022] [Revised: 10/27/2022] [Accepted: 11/13/2022] [Indexed: 11/18/2022]
Abstract
BACKGROUND Alzheimer's disease is a significant public health issue. Recent studies have shown that the gut microbiota plays a vital role in the onset and development of Alzheimer's disease. However, the potential role of the gut microbiota and the associated metabolic characteristics require further elucidation. METHODS The gut microbial compositions of APP/PS1 mice were analyzed using 16S rRNA gene sequencing. Metabolomics was used to characterize changes in metabolic profiles in feces, serum, and cortex. A multi-omics approach investigated the potential associations between gut microbes and metabolites. RESULTS The gut microbiota composition was markedly different between APP/PS1 mice and normal mice. Metabolomic analysis identified 253 fecal metabolites, 16 serum metabolites, and 123 cortical metabolites that were differentially abundant in APP/PS1 that may be potential biomarkers of AD. Nearly half of these metabolites were lipids. A combined analysis of the three sample types showed a correlation between fecal fatty acids and glycerolipids, serum glycerophospholipids, and cortical fatty acids. Furthermore, our study showed that Marinifilaceae and Akkermansiaceae were closely related to these lipids and lipid-like molecules, particularly fatty acids and glycerophospholipids. CONCLUSION Our study highlighted the interactions between the gut microbiome and the fecal, serum, and cortical metabolomes. This interaction provides a new direction for further exploring the link between gut microbiota composition and metabolism in Alzheimer's disease.
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Affiliation(s)
- Xin Cheng
- Department of Integrated Traditional Chinese & Western Medicine, The Second Xiangya Hospital, Central South University, Changsha, 410011, China; National Clinical Research Center for Mental Disorder, Changsha, 410011, China
| | - Yejun Tan
- School of Mathematics, University of Minnesota Twin Cities, Minneapolis, 55455, MN, USA
| | - Hongli Li
- Department of Integrated Traditional Chinese & Western Medicine, The Second Xiangya Hospital, Central South University, Changsha, 410011, China; National Clinical Research Center for Mental Disorder, Changsha, 410011, China
| | - Jianhua Huang
- Hunan Academy of Chinese Medicine, Changsha, 410013, China
| | - Di Zhao
- Hunan Academy of Chinese Medicine, Changsha, 410013, China
| | - Zheyu Zhang
- Department of Integrated Traditional Chinese & Western Medicine, The Second Xiangya Hospital, Central South University, Changsha, 410011, China; National Clinical Research Center for Mental Disorder, Changsha, 410011, China
| | - Min Yi
- Department of Integrated Traditional Chinese & Western Medicine, The Second Xiangya Hospital, Central South University, Changsha, 410011, China; National Clinical Research Center for Mental Disorder, Changsha, 410011, China
| | - Lemei Zhu
- Academician Workstation, Changsha Medical University, Changsha, 410219, China
| | - Shan Hui
- Department of Geratology, Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, 410005, China
| | - Jingjing Yang
- Teaching and Research Section of Clinical Nursing, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Weijun Peng
- Department of Integrated Traditional Chinese & Western Medicine, The Second Xiangya Hospital, Central South University, Changsha, 410011, China; National Clinical Research Center for Mental Disorder, Changsha, 410011, China.
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Behavioral Phenotyping of Bbs6 and Bbs8 Knockout Mice Reveals Major Alterations in Communication and Anxiety. Int J Mol Sci 2022; 23:ijms232314506. [PMID: 36498834 PMCID: PMC9741393 DOI: 10.3390/ijms232314506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/14/2022] [Accepted: 11/17/2022] [Indexed: 11/23/2022] Open
Abstract
The primary cilium is an organelle with a central role in cellular signal perception. Mutations in genes that encode cilia-associated proteins result in a collection of human syndromes collectively termed ciliopathies. Of these, the Bardet-Biedl syndrome (BBS) is considered one of the archetypical ciliopathies, as patients exhibit virtually all respective clinical phenotypes, such as pathological changes of the retina or the kidney. However, the behavioral phenotype associated with ciliary dysfunction has received little attention thus far. Here, we extensively characterized the behavior of two rodent models of BBS, Bbs6/Mkks, and Bbs8/Ttc8 knockout mice concerning social behavior, anxiety, and cognitive abilities. While learning tasks remained unaffected due to the genotype, we observed diminished social behavior and altered communication. Additionally, Bbs knockout mice displayed reduced anxiety. This was not due to altered adrenal gland function or corticosterone serum levels. However, hypothalamic expression of Lsamp, the limbic system associated protein, and Adam10, a protease acting on Lsamp, were reduced. This was accompanied by changes in characteristics of adult hypothalamic neurosphere cultures. In conclusion, we provide evidence that behavioral changes in Bbs knockout mice are mainly found in social and anxiety traits and might be based on an altered architecture of the hypothalamus.
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10
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Thu Thuy Nguyen V, Endres K. Targeting gut microbiota to alleviate neuroinflammation in Alzheimer's disease. Adv Drug Deliv Rev 2022; 188:114418. [PMID: 35787390 DOI: 10.1016/j.addr.2022.114418] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 02/08/2023]
Abstract
The gut microbiota came into focus within the last years regarding being associated with or even underlying neuropsychiatric diseases. The existence of the gut-brain-axis makes it highly plausible that bacterial metabolites or toxins that escape the intestinal environment or approach the vagal connections towards the brain, exert devastating effects on the central nervous system. In Alzheimer's disease (AD), growing evidence for dysbiotic changes in the gut microbiota is obtained, even though the question for cause or consequence remains open. Nevertheless, using modulation of microbiota to address inflammatory processes seems an attractive therapeutic approach as certain microbial products such as short chain fatty acids have been proven to exert beneficial cognitive effects. In this review, we summarize, contemporary knowledge on neuroinflammation and inflammatory processes within the brain and even more detailed in the gut in AD, try to conclude whom to target regarding human microbial commensals and report on current interventional trials.
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Affiliation(s)
- Vu Thu Thuy Nguyen
- Department of Psychiatry and Psychotherapy, University Medical Center Mainz, Johannes Gutenberg-University Mainz, Germany
| | - Kristina Endres
- Department of Psychiatry and Psychotherapy, University Medical Center Mainz, Johannes Gutenberg-University Mainz, Germany.
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Resilience and the Gut Microbiome: Insights from Chronically Socially Stressed Wild-Type Mice. Microorganisms 2022; 10:microorganisms10061077. [PMID: 35744594 PMCID: PMC9231072 DOI: 10.3390/microorganisms10061077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/12/2022] [Accepted: 05/19/2022] [Indexed: 12/12/2022] Open
Abstract
The microbiome is an important player within physiological homeostasis of the body but also in pathophysiological derailments. Chronic social stress is a challenge to the organism, which results in psychological illnesses such as depression in some individuals and can be counterbalanced by others, namely resilient individuals. In this study, we wanted to elucidate the potential contribution of the microbiome to promote resilience. Male mice were subjected to the classical chronic social defeat paradigm. Defeated or undefeated mice were either controls (receiving normal drinking water) or pre-treated with antibiotics or probiotics. Following social defeat, resilient behavior was assessed by means of the social interaction test. Neither depletion nor probiotic-shifted alteration of the microbiome influenced stress-associated behavioral outcomes. Nevertheless, clear changes in microbiota composition due to the defeat stress were observed such as elevated Bacteroides spp. This stress-induced increase in Bacteroides in male mice could be confirmed in a related social stress paradigm (instable social hierarchy) in females. This indicates that while manipulation of the microbiome via the antibiotics- and probiotics-treatment regime used here has no direct impact on modulating individual stress susceptibility in rodents, it clearly affects the microbiome in the second line and in a sex-independent manner regarding Bacteroides.
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12
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Blood-Based Biomarkers for Alzheimer's Disease Diagnosis and Progression: An Overview. Cells 2022; 11:cells11081367. [PMID: 35456047 PMCID: PMC9044750 DOI: 10.3390/cells11081367] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 04/12/2022] [Accepted: 04/15/2022] [Indexed: 01/10/2023] Open
Abstract
Alzheimer’s Disease (AD) is a progressive neurodegenerative disease characterized by amyloid-β (Aβ) plaque deposition and neurofibrillary tangle accumulation in the brain. Although several studies have been conducted to unravel the complex and interconnected pathophysiology of AD, clinical trial failure rates have been high, and no disease-modifying therapies are presently available. Fluid biomarker discovery for AD is a rapidly expanding field of research aimed at anticipating disease diagnosis and following disease progression over time. Currently, Aβ1–42, phosphorylated tau, and total tau levels in the cerebrospinal fluid are the best-studied fluid biomarkers for AD, but the need for novel, cheap, less-invasive, easily detectable, and more-accessible markers has recently led to the search for new blood-based molecules. However, despite considerable research activity, a comprehensive and up-to-date overview of the main blood-based biomarker candidates is still lacking. In this narrative review, we discuss the role of proteins, lipids, metabolites, oxidative-stress-related molecules, and cytokines as possible disease biomarkers. Furthermore, we highlight the potential of the emerging miRNAs and long non-coding RNAs (lncRNAs) as diagnostic tools, and we briefly present the role of vitamins and gut-microbiome-related molecules as novel candidates for AD detection and monitoring, thus offering new insights into the diagnosis and progression of this devastating disease.
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Varesi A, Pierella E, Romeo M, Piccini GB, Alfano C, Bjørklund G, Oppong A, Ricevuti G, Esposito C, Chirumbolo S, Pascale A. The Potential Role of Gut Microbiota in Alzheimer’s Disease: from Diagnosis to Treatment. Nutrients 2022; 14:nu14030668. [PMID: 35277027 PMCID: PMC8840394 DOI: 10.3390/nu14030668] [Citation(s) in RCA: 70] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 02/02/2022] [Accepted: 02/03/2022] [Indexed: 12/04/2022] Open
Abstract
Gut microbiota is emerging as a key regulator of many disease conditions and its dysregulation is implicated in the pathogenesis of several gastrointestinal and extraintestinal disorders. More recently, gut microbiome alterations have been linked to neurodegeneration through the increasingly defined gut microbiota brain axis, opening the possibility for new microbiota-based therapeutic options. Although several studies have been conducted to unravel the possible relationship between Alzheimer’s Disease (AD) pathogenesis and progression, the diagnostic and therapeutic potential of approaches aiming at restoring gut microbiota eubiosis remain to be fully addressed. In this narrative review, we briefly summarize the role of gut microbiota homeostasis in brain health and disease, and we present evidence for its dysregulation in AD patients. Based on these observations, we then discuss how dysbiosis might be exploited as a new diagnostic tool in early and advanced disease stages, and we examine the potential of prebiotics, probiotics, fecal microbiota transplantation, and diets as complementary therapeutic interventions on disease pathogenesis and progression, thus offering new insights into the diagnosis and treatment of this devastating and progressive disease.
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Affiliation(s)
- Angelica Varesi
- Department of Biology and Biotechnology, University of Pavia, 27100 Pavia, Italy;
- Almo Collegio Borromeo, 27100 Pavia, Italy
- Correspondence: (A.V.); (G.R.)
| | - Elisa Pierella
- School of Medicine, Faculty of Clinical and Biomedical Sciences, University of Central Lancashire, Preston PR1 2HE, UK; (E.P.); (A.O.)
| | - Marcello Romeo
- Department of Biology and Biotechnology, University of Pavia, 27100 Pavia, Italy;
| | | | - Claudia Alfano
- Department of Emergency Medicine and Surgery, IRCCS Fondazione Policlinico San Matteo, 27100 Pavia, Italy;
| | - Geir Bjørklund
- Council for Nutritional and Environmental Medicine (CONEM), 8610 Mo i Rana, Norway;
| | - Abigail Oppong
- School of Medicine, Faculty of Clinical and Biomedical Sciences, University of Central Lancashire, Preston PR1 2HE, UK; (E.P.); (A.O.)
| | - Giovanni Ricevuti
- Department of Drug Sciences, University of Pavia, 27100 Pavia, Italy
- Correspondence: (A.V.); (G.R.)
| | - Ciro Esposito
- Unit of Nephrology and Dialysis, ICS Maugeri, University of Pavia, 27100 Pavia, Italy;
| | - Salvatore Chirumbolo
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37121 Verona, Italy;
| | - Alessia Pascale
- Section of Pharmacology, Department of Drug Sciences, University of Pavia, 27100 Pavia, Italy;
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