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Popescu C, Munteanu C, Anghelescu A, Ciobanu V, Spînu A, Andone I, Mandu M, Bistriceanu R, Băilă M, Postoiu RL, Vlădulescu-Trandafir AI, Giuvara S, Malaelea AD, Onose G. Novelties on Neuroinflammation in Alzheimer's Disease-Focus on Gut and Oral Microbiota Involvement. Int J Mol Sci 2024; 25:11272. [PMID: 39457054 PMCID: PMC11508522 DOI: 10.3390/ijms252011272] [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: 09/23/2024] [Revised: 10/05/2024] [Accepted: 10/17/2024] [Indexed: 10/28/2024] Open
Abstract
Recent studies underscore the role of gut and oral microbiota in influencing neuroinflammation through the microbiota-gut-brain axis, including in Alzheimer's disease (AD). This review aims to provide a comprehensive synthesis of recent findings on the involvement of gut and oral microbiota in the neuroinflammatory processes associated with AD, emphasizing novel insights and therapeutic implications. This review reveals that dysbiosis in AD patients' gut and oral microbiota is linked to heightened peripheral and central inflammatory responses. Specific bacterial taxa, such as Bacteroides and Firmicutes in the gut, as well as Porphyromonas gingivalis in the oral cavity, are notably altered in AD, leading to significant changes in microglial activation and cytokine production. Gut microbiota alterations are associated with increased intestinal permeability, facilitating the translocation of endotoxins like lipopolysaccharides (LPS) into the bloodstream and exacerbating neuroinflammation by activating the brain's toll-like receptor 4 (TLR4) pathways. Furthermore, microbiota-derived metabolites, including short-chain fatty acids (SCFAs) and amyloid peptides, can cross the blood-brain barrier and modulate neuroinflammatory responses. While microbial amyloids may contribute to amyloid-beta aggregation in the brain, certain SCFAs like butyrate exhibit anti-inflammatory properties, suggesting a potential therapeutic avenue to mitigate neuroinflammation. This review not only highlights the critical role of microbiota in AD pathology but also offers a ray of hope by suggesting that modulating gut and oral microbiota could represent a novel therapeutic strategy for reducing neuroinflammation and slowing disease progression.
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Affiliation(s)
- Cristina Popescu
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
| | - Constantin Munteanu
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
- Department of Biomedical Sciences, Faculty of Medical Bioengineering, University of Medicine and Pharmacy “Grigore T. Popa” Iași, 700454 Iași, Romania
| | - Aurelian Anghelescu
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
| | - Vlad Ciobanu
- Department of Computer Science and Engineering, Faculty for Automatic Control and Computers, University Politehnica of Bucharest, 060042 Bucharest, Romania;
| | - Aura Spînu
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
| | - Ioana Andone
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
| | - Mihaela Mandu
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
| | - Roxana Bistriceanu
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
| | - Mihai Băilă
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
| | - Ruxandra-Luciana Postoiu
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
| | - Andreea-Iulia Vlădulescu-Trandafir
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
| | - Sebastian Giuvara
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
| | - Alin-Daniel Malaelea
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
| | - Gelu Onose
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020022 Bucharest, Romania; (C.P.); (A.A.); (A.S.); (I.A.); (R.B.); (M.B.); (R.-L.P.); (A.-I.V.-T.); (S.G.); (A.-D.M.); (G.O.)
- Neuromuscular Rehabilitation Clinic Division, Clinical Emergency Hospital “Bagdasar-Arseni”, 041915 Bucharest, Romania
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Fu C, Wang X, Zhou W, Gao Q, Luo J, Li Y. Exploring the mechanism of chondroitin sulfate-selenium nanoparticles in improving Alzheimer's disease: Insights from intestinal flora evaluation. Heliyon 2024; 10:e38635. [PMID: 39421360 PMCID: PMC11483475 DOI: 10.1016/j.heliyon.2024.e38635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 09/13/2024] [Accepted: 09/26/2024] [Indexed: 10/19/2024] Open
Abstract
In this study we have investigated the effect of chondroitin sulfate-selenium nanoparticles (CS@Se) on Alzheimer's disease (AD) mice using 16S rDNA technique. We randomly divided 30 SPF grade male C57BL/6 J mice into 6 groups according to random number table method. The AD mouse model was established by subcutaneous injection of D-galactose (D-gal) combined with gavage of AlCl3 for 30 consecutive days, and then drug intervention was performed in the administration group for 40 consecutive days. The findings demonstrated several positive effects of CS@Se on AD mice. Firstly, CS@Se improved spatial learning and memory problems and reduces anxiety in AD mice. It also significantly reduced pyramidal cell arrangement disorder and rupture, leading to an improvement in synaptic structure damage between hippocampal neurons. Furthermore, CS@Se reduced mitochondrial swelling and vacuolation while increasing neuron survival in AD mice. Moreover, CS@Se significantly impacted the diversity and richness of intestinal flora in AD mice. It increased the relative abundance of Firmicutes and Actinobacteria while reducing the relative abundance of Bacteroidetes and Proteobacteria. In conclusion, CS@Se effectively reduced the breakdown of hippocampal pyramidal cells, improved the superfiber structure of hippocampal neurons, and restored intestinal flora balance, ultimately contributing to improving learning and memory abilities and alleviating anxiety in AD mice.
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Affiliation(s)
- Changfang Fu
- School of Pharmaceutical Sciences & Institute of Materia Medica, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250117, China
- Taishan vocational college of nursing, Taian 271000, China
| | - Xinyue Wang
- School of Pharmaceutical Sciences & Institute of Materia Medica, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250117, China
| | - Wei Zhou
- School of Pharmaceutical Sciences & Institute of Materia Medica, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250117, China
- Heze Health School in Shandong Province, Heze 274000, China
| | - Qi Gao
- School of Pharmaceutical Sciences & Institute of Materia Medica, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250117, China
- Key Laboratory of Clinical Pharmacology, Liao cheng People's Hospital, Liaocheng 252000, China
| | - Junjun Luo
- School of Pharmaceutical Sciences & Institute of Materia Medica, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250117, China
| | - Yuqin Li
- School of Pharmaceutical Sciences & Institute of Materia Medica, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250117, China
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Capocchi JK, Figueroa-Romero C, Dunham SJB, Faraci G, Rothman JA, Whiteson KL, Seo DO, Holtzman DM, Grabrucker S, Nolan YM, Kaddurah-Daouk R, Jett DA. Symposium: What Does the Microbiome Tell Us about Prevention and Treatment of AD/ADRD? J Neurosci 2024; 44:e1295242024. [PMID: 39384409 PMCID: PMC11466070 DOI: 10.1523/jneurosci.1295-24.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2024] [Revised: 07/17/2024] [Accepted: 08/19/2024] [Indexed: 10/11/2024] Open
Abstract
Alzheimer's disease (AD) and Alzheimer's disease-related dementias (ADRDs) are broad-impact multifactorial neurodegenerative diseases. Their complexity presents unique challenges for developing effective therapies. This review highlights research presented at the 2024 Society for Neuroscience meeting which emphasized the gut microbiome's role in AD pathogenesis by influencing brain function and neurodegeneration through the microbiota-gut-brain axis. This emerging evidence underscores the potential for targeting the gut microbiota to treat AD/ADRD.
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Affiliation(s)
| | | | | | - Gina Faraci
- University of California, Irvine, Irvine, California 92697
| | - Jason A Rothman
- University of California, Irvine, Irvine, California 92697
- University of California, Riverside, Riverside, California 92521
| | | | - Dong-Oh Seo
- Washington University School of Medicine in St. Louis, St. Louis, Missouri 63110
| | - David M Holtzman
- Washington University School of Medicine in St. Louis, St. Louis, Missouri 63110
| | - Stefanie Grabrucker
- Department of Anatomy and Neuroscience, University College Cork, Cork T12 XF62, Ireland
| | - Yvonne M Nolan
- Department of Anatomy and Neuroscience, University College Cork, Cork T12 XF62, Ireland
- APC Microbiome Ireland, University College Cork, Cork T12 YT20, Ireland
| | | | - David A Jett
- National Institute of Neurological Disorders and Stroke, Rockville, Maryland 20852
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Pasupalak JK, Rajput P, Gupta GL. Gut microbiota and Alzheimer's disease: Exploring natural product intervention and the Gut-Brain axis for therapeutic strategies. Eur J Pharmacol 2024; 984:177022. [PMID: 39362390 DOI: 10.1016/j.ejphar.2024.177022] [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: 07/11/2024] [Revised: 09/14/2024] [Accepted: 09/30/2024] [Indexed: 10/05/2024]
Abstract
Numerous studies conducted over the last ten years have shown a strong correlation between the gut microbiota and the onset and progression of Alzheimer's disease (AD). However, the exact underlying mechanism is still unknown. An ongoing communication mechanism linking the gut and the brain is highlighted by the term "microbiota-gut-brain axis," which was originally coined the "gut-brain axis." Key metabolic, endocrine, neurological, and immunological mechanisms are involved in the microbiota‒gut‒brain axis and are essential for preserving brain homeostasis. Thus, the main emphasis of this review is how the gut microbiota contributes to the development of AD and how various natural products intervene in this disease. The first part of the review provides an outline of various pathways and relationships between the brain and gut microbiota, and the second part provides various mechanisms involved in the gut microbiota and AD. Finally, this review provides knowledge about natural products and their effectiveness in treating gut microbiota-induced AD. AD may be treated in the future by altering the gut microbiota with a customized diet, probiotics/prebiotics, plant products, and natural products. This entails altering the microbiological partners and products (such as amyloid protein) that these partners generate.
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Affiliation(s)
- Jajati K Pasupalak
- School of Pharmacy & Technology Management, SVKM'S NMIMS Deemed-to-be University, Shirpur, Maharashtra, 425405, India
| | - Prabha Rajput
- School of Pharmacy & Technology Management, SVKM'S NMIMS Deemed-to-be University, Shirpur, Maharashtra, 425405, India
| | - Girdhari Lal Gupta
- School of Pharmacy & Technology Management, SVKM'S NMIMS Deemed-to-be University, Shirpur, Maharashtra, 425405, India.
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Kolobaric A, Andreescu C, Jašarević E, Hong CH, Roh HW, Cheong JY, Kim YK, Shin TS, Kang CS, Kwon CO, Yoon SY, Hong SW, Aizenstein HJ, Karim HT, Son SJ. Gut microbiome predicts cognitive function and depressive symptoms in late life. Mol Psychiatry 2024; 29:3064-3075. [PMID: 38664490 PMCID: PMC11449789 DOI: 10.1038/s41380-024-02551-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 03/29/2024] [Accepted: 04/03/2024] [Indexed: 10/05/2024]
Abstract
Depression in older adults with cognitive impairment increases progression to dementia. Microbiota is associated with current mood and cognition, but the extent to which it predicts future symptoms is unknown. In this work, we identified microbial features that reflect current and predict future cognitive and depressive symptoms. Clinical assessments and stool samples were collected from 268 participants with varying cognitive and depressive symptoms. Seventy participants underwent 2-year follow-up. Microbial community diversity, structure, and composition were assessed using high-resolution 16 S rRNA marker gene sequencing. We implemented linear regression to characterize the relationship between microbiome composition, current cognitive impairment, and depressive symptoms. We leveraged elastic net regression to discover features that reflect current or future cognitive function and depressive symptoms. Greater microbial community diversity associated with lower current cognition in the whole sample, and greater depression in participants not on antidepressants. Poor current cognitive function associated with lower relative abundance of Bifidobacterium, while greater GABA degradation associated with greater current depression severity. Future cognitive decline associated with lower cognitive function, lower relative abundance of Intestinibacter, lower glutamate degradation, and higher baseline histamine synthesis. Future increase in depressive symptoms associated with higher baseline depression and anxiety, lower cognitive function, diabetes, lower relative abundance of Bacteroidota, and lower glutamate degradation. Our results suggest cognitive dysfunction and depression are unique states with an overall biological effect detectable through gut microbiota. The microbiome may present a noninvasive readout and prognostic tool for cognitive and psychiatric states.
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Affiliation(s)
- A Kolobaric
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, USA
| | - C Andreescu
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - E Jašarević
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, USA
- Department of Computational and Systems Biology, University of Pittsburgh School of Medicine, Pittsburgh, USA
- Magee-Womens Research Institute, Pittsburgh, USA
| | - C H Hong
- Department of Psychiatry, Ajou University School of Medicine, Suwon, Republic of Korea
| | - H W Roh
- Department of Psychiatry, Ajou University School of Medicine, Suwon, Republic of Korea
| | - J Y Cheong
- Department of Gastroenterology, Ajou University School of Medicine, Suwon, Republic of Korea
| | - Y K Kim
- Institute of MD Healthcare Inc, Seoul, Republic of Korea
| | - T S Shin
- Institute of MD Healthcare Inc, Seoul, Republic of Korea
| | - C S Kang
- Institute of MD Healthcare Inc, Seoul, Republic of Korea
| | - C O Kwon
- Institute of MD Healthcare Inc, Seoul, Republic of Korea
| | - S Y Yoon
- Institute of MD Healthcare Inc, Seoul, Republic of Korea
| | - S W Hong
- Department of Psychiatry, Ajou University School of Medicine, Suwon, Republic of Korea
| | - H J Aizenstein
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, USA
- Department of Bioengineering, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - H T Karim
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, USA.
- Department of Bioengineering, University of Pittsburgh School of Medicine, Pittsburgh, USA.
| | - S J Son
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, USA.
- Department of Psychiatry, Ajou University School of Medicine, Suwon, Republic of Korea.
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Lim L. Modifying Alzheimer's disease pathophysiology with photobiomodulation: model, evidence, and future with EEG-guided intervention. Front Neurol 2024; 15:1407785. [PMID: 39246604 PMCID: PMC11377238 DOI: 10.3389/fneur.2024.1407785] [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: 03/27/2024] [Accepted: 08/01/2024] [Indexed: 09/10/2024] Open
Abstract
This manuscript outlines a model of Alzheimer's Disease (AD) pathophysiology in progressive layers, from its genesis to the development of biomarkers and then to symptom expression. Genetic predispositions are the major factor that leads to mitochondrial dysfunction and subsequent amyloid and tau protein accumulation, which have been identified as hallmarks of AD. Extending beyond these accumulations, we explore a broader spectrum of pathophysiological aspects, including the blood-brain barrier, blood flow, vascular health, gut-brain microbiodata, glymphatic flow, metabolic syndrome, energy deficit, oxidative stress, calcium overload, inflammation, neuronal and synaptic loss, brain matter atrophy, and reduced growth factors. Photobiomodulation (PBM), which delivers near-infrared light to selected brain regions using portable devices, is introduced as a therapeutic approach. PBM has the potential to address each of these pathophysiological aspects, with data provided by various studies. They provide mechanistic support for largely small published clinical studies that demonstrate improvements in memory and cognition. They inform of PBM's potential to treat AD pending validation by large randomized controlled studies. The presentation of brain network and waveform changes on electroencephalography (EEG) provide the opportunity to use these data as a guide for the application of various PBM parameters to improve outcomes. These parameters include wavelength, power density, treatment duration, LED positioning, and pulse frequency. Pulsing at specific frequencies has been found to influence the expression of waveforms and modifications of brain networks. The expression stems from the modulation of cellular and protein structures as revealed in recent studies. These findings provide an EEG-based guide for the use of artificial intelligence to personalize AD treatment through EEG data feedback.
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Affiliation(s)
- Lew Lim
- Vielight Inc., Toronto, ON, Canada
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Chen G, Jin Y, Chu C, Zheng Y, Chen Y, Zhu X. Genetic prediction of blood metabolites mediating the relationship between gut microbiota and Alzheimer's disease: a Mendelian randomization study. Front Microbiol 2024; 15:1414977. [PMID: 39224217 PMCID: PMC11366617 DOI: 10.3389/fmicb.2024.1414977] [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: 04/10/2024] [Accepted: 07/22/2024] [Indexed: 09/04/2024] Open
Abstract
Background Observational studies have suggested an association between gut microbiota and Alzheimer's disease (AD); however, the causal relationship remains unclear, and the role of blood metabolites in this association remains elusive. Purpose To elucidate the causal relationship between gut microbiota and AD and to investigate whether blood metabolites serve as potential mediators. Materials and methods Univariable Mendelian randomization (UVMR) analysis was employed to assess the causal relationship between gut microbiota and AD, while multivariable MR (MVMR) was utilized to mitigate confounding factors. Subsequently, a two-step mediation MR approach was employed to explore the role of blood metabolites as potential mediators. We primarily utilized the inverse variance-weighted method to evaluate the causal relationship between exposure and outcome, and sensitivity analyses including Contamination mixture, Maximum-likelihood, Debiased inverse-variance weighted, MR-Egger, Bayesian Weighted Mendelian randomization, and MR pleiotropy residual sum and outlier were conducted to address pleiotropy. Results After adjustment for reverse causality and MVMR correction, class Actinobacteria (OR: 1.03, 95% CI: 1.01-1.06, p = 0.006), family Lactobacillaceae (OR: 1.03, 95% CI: 1.00-1.05, p = 0.017), genus Lachnoclostridium (OR: 1.03, 95% CI: 1.00-1.06, p = 0.019), genus Ruminiclostridium9 (OR: 0.97, 95% CI: 0.94-1.00, p = 0.027) and genus Ruminiclostridium6 (OR: 1.03, 95% CI: 1.01-1.05, p = 0.009) exhibited causal effects on AD. Moreover, 1-ribosyl-imidazoleacetate levels (-6.62%), Metabolonic lactone sulfate levels (2.90%), and Nonadecanoate (19:0) levels (-12.17%) mediated the total genetic predictive effects of class Actinobacteria on AD risk. Similarly, 2-stearoyl-GPE (18:0) levels (-9.87%), Octadecanedioylcarnitine (C18-DC) levels (4.44%), 1-(1-enyl-stearoyl)-2-oleoyl-GPE (p-18:0/18:1) levels (38.66%), and X-23639 levels (13.28%) respectively mediated the total genetic predictive effects of family Lactobacillaceae on AD risk. Furthermore, Hexadecanedioate (C16-DC) levels (5.45%) mediated the total genetic predictive effects of genus Ruminiclostridium 6 on AD risk; Indole-3-carboxylate levels (13.91%), X-13431 levels (7.08%), Alpha-ketoglutarate to succinate ratio (-13.91%), 3-phosphoglycerate to glycerate ratio (15.27%), and Succinate to proline ratio (-14.64%) respectively mediated the total genetic predictive effects of genus Ruminiclostridium 9 on AD risk. Conclusion Our mediation MR analysis provides genetic evidence suggesting the potential mediating role of blood metabolites in the causal relationship between gut microbiota and AD. Further large-scale randomized controlled trials are warranted to validate the role of blood metabolites in the specific mechanisms by which gut microbiota influence AD.
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Affiliation(s)
- Guanglei Chen
- Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
| | - Yaxian Jin
- The First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
| | - Cancan Chu
- Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
| | - Yuhao Zheng
- Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
| | - Yunzhi Chen
- Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
| | - Xing Zhu
- Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou, China
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Wang F, Yao Z, Jin T, Mao B, Shao S, Shao C. Research progress on Helicobacter pylori infection related neurological diseases. Ageing Res Rev 2024; 99:102399. [PMID: 38955263 DOI: 10.1016/j.arr.2024.102399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 06/25/2024] [Accepted: 06/25/2024] [Indexed: 07/04/2024]
Abstract
Helicobacter pylori, a type of gram-negative bacterium, infects roughly half of the global population. It is strongly associated with gastrointestinal disorders like gastric cancer, peptic ulcers, and chronic gastritis. Moreover, numerous studies have linked this bacterium to various extra-gastric conditions, including hematologic, cardiovascular, and neurological issues. Specifically, research has shown that Helicobacter pylori interacts with the brain through the microbiota-gut-brain axis, thereby increasing the risk of neurological disorders. The inflammatory mediators released by Helicobacter pylori-induced chronic gastritis may disrupt the function of the blood-brain barrier by interfering with the transmission or direct action of neurotransmitters. This article examines the correlation between Helicobacter pylori and a range of conditions, such as hyperhomocysteinemia, schizophrenia, Alzheimer's disease, Parkinson's disease, ischemic stroke, multiple sclerosis, migraine, and Guillain-Barré syndrome.
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Affiliation(s)
- Fan Wang
- School of Medicine, Jiangsu University, Zhenjiang 212013, China; Yixing Hospital Affiliated to Jiangsu University, Yixing 214200, China
| | - Zhendong Yao
- Yixing Hospital Affiliated to Jiangsu University, Yixing 214200, China
| | - Tao Jin
- Yixing Hospital Affiliated to Jiangsu University, Yixing 214200, China
| | - Boneng Mao
- Yixing Hospital Affiliated to Jiangsu University, Yixing 214200, China.
| | - Shihe Shao
- School of Medicine, Jiangsu University, Zhenjiang 212013, China; Yixing Hospital Affiliated to Jiangsu University, Yixing 214200, China; Affiliated Hospital of Jiangsu University, Zhenjiang 212013, China.
| | - Chen Shao
- Affiliated Hospital of Jiangsu University, Zhenjiang 212013, China.
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曾 静, 陈 荣, 任 香, 花 雷, 阳 勇, 魏 江, 张 小. [ Yigong San improves cognitive decline in a rat model of Alzheimer's disease by regulating intestinal microorganisms]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2024; 44:1297-1305. [PMID: 39051075 PMCID: PMC11270669 DOI: 10.12122/j.issn.1673-4254.2024.07.09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Indexed: 07/27/2024]
Abstract
OBJECTIVE To investigate the effect of Yigong San (YGS) on learning and memory abilities of rats with lipopolysaccharide (LPS)‑induced cognitive decline and explore its possible mechanism in light of intestinal microbiota. METHODS Forty SD rats were randomly divided into control group, model group, donepezil (1.3 mg/kg) group, and high-dose (5.25 g/kg) and low-dose (2.63 g/kg) YGS treatment groups. After 24 days of treatment with the corresponding drugs or water by gavage, the rats in the latter 4 groups received an intraperitoneal injection of LPS (0.5 mg/kg) to establish models of Alzheimer's disease (AD). Water maze test and HE staining were used to evaluate the changes in learning and memory abilities and pathomorphology of the hippocampus. The changes in gut microbial species of the rats were analyzed with 16S rRNA sequencing, and the levels of IL-6, TNF-α, and IL-1β in the brain tissue and serum were detected using ELISA. RESULTS Compared with the AD model group, the YGS-treated rats showed significantly shortened escape latency on day 5 after modeling, reduced neuronal degeneration and necrosis in the hippocampus, lowered pathological score of cell damage, and decreased levels IL-6, TNF-α and IL-1β in the brain tissue and serum. The YGS-treated rats showed also obvious reduction of Alpha diversity indicators (ACE and Chao1) of intestinal microbiota with significantly increased abundance of Prevotellaceae species at the family level and decreased abundance of Desulfovibrionaceae, which were involved in such metabolic signaling pathways as cell community prokaryotes, membrane transport, and energy metabolism. CONCLUSION YGS improves learning and memory abilities and hippocampal pathomorphology in AD rat models possibly by regulating the abundance of intestinal microbial species such as Prevotellaceae to affect the metabolic pathways for signal transduction, cofactors, and vitamin metabolism.
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Monaco M, Trebesova H, Grilli M. Muscarinic Receptors and Alzheimer's Disease: New Perspectives and Mechanisms. Curr Issues Mol Biol 2024; 46:6820-6835. [PMID: 39057049 PMCID: PMC11276210 DOI: 10.3390/cimb46070407] [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: 06/04/2024] [Revised: 06/28/2024] [Accepted: 06/29/2024] [Indexed: 07/28/2024] Open
Abstract
Alzheimer's disease (AD) is one of the most prevalent neurodegenerative diseases on a global scale. Historically, this pathology has been linked to cholinergic transmission, and despite the scarcity of effective therapies, numerous alternative processes and targets have been proposed as potential avenues for comprehending this complex illness. Nevertheless, the fundamental pathophysiological mechanisms underpinning AD remain largely enigmatic, with a growing body of evidence advocating for the significance of muscarinic receptors in modulating the brain's capacity to adapt and generate new memories. This review summarizes the current state of the art in the field of muscarinic receptors' involvement in AD. A specific key factor was the relationship between comorbidity and the emergence of new mechanisms.
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Affiliation(s)
- Martina Monaco
- Department of Pharmacy, University of Genoa, Viale Cembrano 4, 16148 Genoa, Italy; (M.M.); (H.T.)
| | - Hanna Trebesova
- Department of Pharmacy, University of Genoa, Viale Cembrano 4, 16148 Genoa, Italy; (M.M.); (H.T.)
| | - Massimo Grilli
- Department of Pharmacy, University of Genoa, Viale Cembrano 4, 16148 Genoa, Italy; (M.M.); (H.T.)
- Inter-University Center for the Promotion of the 3Rs Principles in Teaching & Research (Centro 3R), 16148 Genoa, Italy
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11
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Kang T, Zheng J, Jiang C, Jin L, Li C, Chen B, Shen Y. Amelioration of walnut, peony seed and camellia seed oils against D-galactose-induced cognitive impairment in mice by regulating gut microbiota. Food Funct 2024; 15:7063-7080. [PMID: 38867661 DOI: 10.1039/d4fo01409j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
Diet adjustment will affect the health of gut microbiota, which in turn influences the development and function of the organism's brain through the gut-brain axis. Walnut oil (WO), peony seed oil (PSO) and camellia seed oil (CSO), as typical representatives of woody plant oils, have been shown to have the potential to improve cognitive impairment in mice, but the function mechanisms are not clear. In this study, we comparatively investigated the neuroprotective effects of these three oils on D-galactose (D-gal)-induced cognitive impairment in mice, and found that the ameliorative effect of WO was more prominent. During the behavioral experiments, supplementation with all three oils would improve spatial learning and memory functions in D-gal mice, with a significant reduction in the error times (p < 0.001) and a significant increase in step-down latency (p < 0.001); walnut oil supplementation also significantly increased the number of hidden platform traversals, the target quadrant spent times and percentage of distance (p < 0.05). The results of biomarker analysis showed that WO, in addition to significantly inhibiting D-gal-induced oxidative stress and neuroinflammation as did PSO, significantly increased the ACh content in the mouse brain (p < 0.05) and modulated neurotransmitter levels. The results of further microbiota diversity sequencing experiments also confirmed that dietary supplementation with all three oils affected the diversity and composition of the gut microbiota in mice. Among them, WO significantly restored the balance of the mouse gut microbiota by increasing the abundance of beneficial bacteria (Bacteroidetes, Actinobacteria, Firmicutes) and decreasing the abundance of harmful bacteria (Clostridium, Shigella, Serratia), which was consistent with the results of behavioral experiments and biomarker analyses. Based on the analysis of the fatty acid composition of the three oils and changes in the gut microbiota, it is hypothesized that there is a correlation between the fatty acid composition of the dietary supplement oils and neuroprotective effects. The superiority of WO over PSO and CSO in improving cognitive impairment is mainly attributed to its balanced composition of omega-6 and omega-3 fatty acids.
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Affiliation(s)
- Ting Kang
- Key Laboratory of Synthetic and Natural Functional Molecule of Ministry of Education, College of Chemistry and Materials Science, National Demonstration Center for Experimental Chemistry Education, Northwest University, Xi'an, Shaanxi 710127, China.
| | - Jingyi Zheng
- Key Laboratory of Synthetic and Natural Functional Molecule of Ministry of Education, College of Chemistry and Materials Science, National Demonstration Center for Experimental Chemistry Education, Northwest University, Xi'an, Shaanxi 710127, China.
| | - Chao Jiang
- Key Laboratory of Synthetic and Natural Functional Molecule of Ministry of Education, College of Chemistry and Materials Science, National Demonstration Center for Experimental Chemistry Education, Northwest University, Xi'an, Shaanxi 710127, China.
| | - Lihua Jin
- Key Laboratory of Synthetic and Natural Functional Molecule of Ministry of Education, College of Chemistry and Materials Science, National Demonstration Center for Experimental Chemistry Education, Northwest University, Xi'an, Shaanxi 710127, China.
| | - Cong Li
- Key Laboratory of Synthetic and Natural Functional Molecule of Ministry of Education, College of Chemistry and Materials Science, National Demonstration Center for Experimental Chemistry Education, Northwest University, Xi'an, Shaanxi 710127, China.
| | - Bang Chen
- Key Laboratory of Synthetic and Natural Functional Molecule of Ministry of Education, College of Chemistry and Materials Science, National Demonstration Center for Experimental Chemistry Education, Northwest University, Xi'an, Shaanxi 710127, China.
| | - Yehua Shen
- Key Laboratory of Synthetic and Natural Functional Molecule of Ministry of Education, College of Chemistry and Materials Science, National Demonstration Center for Experimental Chemistry Education, Northwest University, Xi'an, Shaanxi 710127, China.
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12
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Hansen B, Roomp K, Ebid H, Schneider JG. Perspective: The Impact of Fasting and Caloric Restriction on Neurodegenerative Diseases in Humans. Adv Nutr 2024; 15:100197. [PMID: 38432589 PMCID: PMC10997874 DOI: 10.1016/j.advnut.2024.100197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 11/29/2023] [Accepted: 02/23/2024] [Indexed: 03/05/2024] Open
Abstract
Neurodegenerative diseases (NDs) are characterized by the progressive functional and structural denaturation of neurons in the central and peripheral nervous systems. Despite the wide range of genetic predispositions, the increased emergence of these disorders has been associated with a variety of modifiable risk factors, including lifestyle factors. Diet has been shown to influence cognitive alterations in the elderly population with age-related brain pathologies, and specific dietary interventions might, therefore, confer preservatory protection to neural structures. Although Mediterranean and ketogenic diets have been studied, no clear guidelines have been implemented for the prevention or treatment of ND in clinical practice. Murine models have shown that intermittent fasting and caloric restriction (CR) can counteract disease processes in various age-related disorders, including NDs. The objective of this perspective is to provide a comprehensive, comparative overview of the available primary intervention studies on fasting and CR in humans with ND and to elucidate possible links between the mechanisms underlying the effects of fasting, CR, and the neuropathology of ND. We also included all currently available studies in older adults (with and without mild cognitive impairment) in which the primary endpoint was cognitive function to provide further insights into the feasibility and outcomes of such interventions. Overall, we conclude that nutritional intervention trials focusing on fasting and CR in humans with ND have been neglected, and more high-quality studies, including longitudinal clinical intervention trials, are urgently needed to elucidate the underlying immune-metabolic mechanisms in diet and ND.
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Affiliation(s)
- Bérénice Hansen
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Kirsten Roomp
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Hebah Ebid
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Jochen G Schneider
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg; Departments of Internal Medicine II and Psychiatry, Saarland University Medical Center, Homburg, Germany.
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13
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Zou X, Zou G, Zou X, Wang K, Chen Z. Gut microbiota and its metabolites in Alzheimer's disease: from pathogenesis to treatment. PeerJ 2024; 12:e17061. [PMID: 38495755 PMCID: PMC10944166 DOI: 10.7717/peerj.17061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Accepted: 02/15/2024] [Indexed: 03/19/2024] Open
Abstract
Introduction An increasing number of studies have demonstrated that altered microbial diversity and function (such as metabolites), or ecological disorders, regulate bowel-brain axis involvement in the pathophysiologic processes in Alzheimer's disease (AD). The dysregulation of microbes and their metabolites can be a double-edged sword in AD, presenting the possibility of microbiome-based treatment options. This review describes the link between ecological imbalances and AD, the interactions between AD treatment modalities and the microbiota, and the potential of interventions such as prebiotics, probiotics, synbiotics, fecal microbiota transplantation, and dietary interventions as complementary therapeutic strategies targeting AD pathogenesis and progression. Survey methodology Articles from PubMed and china.com on intestinal flora and AD were summarized to analyze the data and conclusions carefully to ensure the comprehensiveness, completeness, and accuracy of this review. Conclusions Regulating the gut flora ecological balance upregulates neurotrophic factor expression, regulates the microbiota-gut-brain (MGB) axis, and suppresses the inflammatory responses. Based on emerging research, this review explored novel directions for future AD research and clinical interventions, injecting new vitality into microbiota research development.
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Affiliation(s)
- Xinfu Zou
- Subject of Integrated Chinese and Western Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Guoqiang Zou
- Subject of Traditional Chinese Medicine, Shandong University Of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Xinyan Zou
- College of Traditional Chinese Medicine, Hebei University, Baoding, Hebei, China
| | - Kangfeng Wang
- Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
| | - Zetao Chen
- Subject of Integrated Chinese and Western Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China
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14
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Amartumur S, Nguyen H, Huynh T, Kim TS, Woo RS, Oh E, Kim KK, Lee LP, Heo C. Neuropathogenesis-on-chips for neurodegenerative diseases. Nat Commun 2024; 15:2219. [PMID: 38472255 PMCID: PMC10933492 DOI: 10.1038/s41467-024-46554-8] [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: 10/04/2023] [Accepted: 02/28/2024] [Indexed: 03/14/2024] Open
Abstract
Developing diagnostics and treatments for neurodegenerative diseases (NDs) is challenging due to multifactorial pathogenesis that progresses gradually. Advanced in vitro systems that recapitulate patient-like pathophysiology are emerging as alternatives to conventional animal-based models. In this review, we explore the interconnected pathogenic features of different types of ND, discuss the general strategy to modelling NDs using a microfluidic chip, and introduce the organoid-on-a-chip as the next advanced relevant model. Lastly, we overview how these models are being applied in academic and industrial drug development. The integration of microfluidic chips, stem cells, and biotechnological devices promises to provide valuable insights for biomedical research and developing diagnostic and therapeutic solutions for NDs.
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Affiliation(s)
- Sarnai Amartumur
- Department of Biophysics, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon, 16419, Korea
| | - Huong Nguyen
- Department of Biophysics, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon, 16419, Korea
| | - Thuy Huynh
- Department of Biophysics, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon, 16419, Korea
| | - Testaverde S Kim
- Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Suwon, 16419, Korea
| | - Ran-Sook Woo
- Department of Anatomy and Neuroscience, College of Medicine, Eulji University, Daejeon, 34824, Korea
| | - Eungseok Oh
- Department of Neurology, Chungnam National University Hospital, Daejeon, 35015, Korea
| | - Kyeong Kyu Kim
- Department of Precision Medicine, Graduate School of Basic Medical Science (GSBMS), Institute for Anti-microbial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, 16419, Korea
| | - Luke P Lee
- Department of Biophysics, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon, 16419, Korea.
- Harvard Medical School, Division of Engineering in Medicine and Renal Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA, 02115, USA.
- Department of Bioengineering, Department of Electrical Engineering and Computer Science, University of California, Berkeley, CA, 94720, USA.
| | - Chaejeong Heo
- Department of Biophysics, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon, 16419, Korea.
- Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Suwon, 16419, Korea.
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15
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Hao W, Luo Q, Tomic I, Quan W, Hartmann T, Menger MD, Fassbender K, Liu Y. Modulation of Alzheimer's disease brain pathology in mice by gut bacterial depletion: the role of IL-17a. Gut Microbes 2024; 16:2363014. [PMID: 38904096 PMCID: PMC11195493 DOI: 10.1080/19490976.2024.2363014] [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: 12/07/2023] [Accepted: 05/29/2024] [Indexed: 06/22/2024] Open
Abstract
Gut bacteria regulate brain pathology of Alzheimer's disease (AD) patients and animal models; however, the underlying mechanism remains unclear. In this study, 3-month-old APP-transgenic female mice with and without knock-out of Il-17a gene were treated with antibiotics-supplemented or normal drinking water for 2 months. The antibiotic treatment eradicated almost all intestinal bacteria, which led to a reduction in Il-17a-expressing CD4-positive T lymphocytes in the spleen and gut, and to a decrease in bacterial DNA in brain tissue. Depletion of gut bacteria inhibited inflammatory activation in both brain tissue and microglia, lowered cerebral Aβ levels, and promoted transcription of Arc gene in the brain of APP-transgenic mice, all of which effects were abolished by deficiency of Il-17a. As possible mechanisms regulating Aβ pathology, depletion of gut bacteria inhibited β-secretase activity and increased the expression of Abcb1 and Lrp1 in the brain or at the blood-brain barrier, which were also reversed by the absence of Il-17a. Interestingly, a crossbreeding experiment between APP-transgenic mice and Il-17a knockout mice further showed that deficiency of Il-17a had already increased Abcb1 and Lrp1 expression at the blood-brain barrier. Thus, depletion of gut bacteria attenuates inflammatory activation and amyloid pathology in APP-transgenic mice via Il-17a-involved signaling pathways. Our study contributes to a better understanding of the gut-brain axis in AD pathophysiology and highlights the therapeutic potential of Il-17a inhibition or specific depletion of gut bacteria that stimulate the development of Il-17a-expressing T cells.
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Affiliation(s)
- Wenlin Hao
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
| | - Qinghua Luo
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
- Department of Neurology, The second affiliated hospital of Nanchang University, Nanchang, China
| | - Inge Tomic
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
| | - Wenqiang Quan
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
- Department of Clinical Laboratory, Tongji Hospital, Tongji University Medical School, Shanghai, China
| | - Tobias Hartmann
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
- Department of Experimental Neurology, Saarland University, Homburg/Saar, Germany
| | - Michael D. Menger
- Department of Experimental Surgery, Saarland University, Homburg/Saar, Germany
| | - Klaus Fassbender
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
| | - Yang Liu
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
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De Marchi F, Vignaroli F, Mazzini L, Comi C, Tondo G. New Insights into the Relationship between Nutrition and Neuroinflammation in Alzheimer's Disease: Preventive and Therapeutic Perspectives. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2024; 23:614-627. [PMID: 37291780 DOI: 10.2174/1871527322666230608110201] [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: 01/02/2023] [Revised: 04/16/2023] [Accepted: 05/08/2023] [Indexed: 06/10/2023]
Abstract
Neurodegenerative diseases are progressive brain disorders characterized by inexorable synaptic dysfunction and neuronal loss. Since the most consistent risk factor for developing neurodegenerative diseases is aging, the prevalence of these disorders is intended to increase with increasing life expectancy. Alzheimer's disease is the most common cause of neurodegenerative dementia, representing a significant medical, social, and economic burden worldwide. Despite growing research to reach an early diagnosis and optimal patient management, no disease-modifying therapies are currently available. Chronic neuroinflammation has been recognized as a crucial player in sustaining neurodegenerative processes, along with pathological deposition of misfolded proteins, including amyloid-β and tau protein. Modulating neuroinflammatory responses may be a promising therapeutic strategy in future clinical trials. Among factors that are able to regulate neuroinflammatory mechanisms, diet, and nutrients represent easily accessible and modifiable lifestyle components. Mediterranean diet and several nutrients, including polyphenols, vitamins, and omega-3 polyunsaturated fatty acids, can exert antioxidant and anti-inflammatory properties, impacting clinical manifestations, cognitive decline, and dementia. This review aims to provide an updated overview of the relationship between neuroinflammation, nutrition, gut microbiota, and neurodegeneration. We summarize the major studies exploring the effects of diet regimes on cognitive decline, primarily focusing on Alzheimer's disease dementia and the impact of these results on the design of ongoing clinical trials.
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Affiliation(s)
- Fabiola De Marchi
- ALS Center, Neurology Unit, Department of Translational Medicine, University of Piemonte Orientale, 28100, Novara, Italy
| | - Francesca Vignaroli
- Neurology Unit, Department of Translational Medicine, University of Piemonte Orientale, 28100, Novara, Italy
| | - Letizia Mazzini
- ALS Center, Neurology Unit, Department of Translational Medicine, University of Piemonte Orientale, 28100, Novara, Italy
| | - Cristoforo Comi
- Neurology Unit, Department of Translational Medicine, S. Andrea Hospital, University of Piemonte Orientale, 13100, Vercelli, Italy
| | - Giacomo Tondo
- Neurology Unit, Department of Translational Medicine, S. Andrea Hospital, University of Piemonte Orientale, 13100, Vercelli, Italy
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Grabrucker S, Marizzoni M, Silajdžić E, Lopizzo N, Mombelli E, Nicolas S, Dohm-Hansen S, Scassellati C, Moretti DV, Rosa M, Hoffmann K, Cryan JF, O’Leary OF, English JA, Lavelle A, O’Neill C, Thuret S, Cattaneo A, Nolan YM. Microbiota from Alzheimer's patients induce deficits in cognition and hippocampal neurogenesis. Brain 2023; 146:4916-4934. [PMID: 37849234 PMCID: PMC10689930 DOI: 10.1093/brain/awad303] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 07/29/2023] [Accepted: 08/19/2023] [Indexed: 10/19/2023] Open
Abstract
Alzheimer's disease is a complex neurodegenerative disorder leading to a decline in cognitive function and mental health. Recent research has positioned the gut microbiota as an important susceptibility factor in Alzheimer's disease by showing specific alterations in the gut microbiome composition of Alzheimer's patients and in rodent models. However, it is unknown whether gut microbiota alterations are causal in the manifestation of Alzheimer's symptoms. To understand the involvement of Alzheimer's patient gut microbiota in host physiology and behaviour, we transplanted faecal microbiota from Alzheimer's patients and age-matched healthy controls into microbiota-depleted young adult rats. We found impairments in behaviours reliant on adult hippocampal neurogenesis, an essential process for certain memory functions and mood, resulting from Alzheimer's patient transplants. Notably, the severity of impairments correlated with clinical cognitive scores in donor patients. Discrete changes in the rat caecal and hippocampal metabolome were also evident. As hippocampal neurogenesis cannot be measured in living humans but is modulated by the circulatory systemic environment, we assessed the impact of the Alzheimer's systemic environment on proxy neurogenesis readouts. Serum from Alzheimer's patients decreased neurogenesis in human cells in vitro and were associated with cognitive scores and key microbial genera. Our findings reveal for the first time, that Alzheimer's symptoms can be transferred to a healthy young organism via the gut microbiota, confirming a causal role of gut microbiota in Alzheimer's disease, and highlight hippocampal neurogenesis as a converging central cellular process regulating systemic circulatory and gut-mediated factors in Alzheimer's.
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Affiliation(s)
- Stefanie Grabrucker
- Department of Anatomy and Neuroscience, University College Cork, Ireland
- APC Microbiome Ireland, University College Cork, Ireland
| | - Moira Marizzoni
- Biological Psychiatry Unit, IRCCS Fatebenefratelli, Brescia, Italy
- Laboratory of Neuroimaging and Alzheimer’s Epidemiology, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Edina Silajdžić
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, King’s College London, SE5 9NU London, UK
| | - Nicola Lopizzo
- Biological Psychiatry Unit, IRCCS Fatebenefratelli, Brescia, Italy
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Elisa Mombelli
- Biological Psychiatry Unit, IRCCS Fatebenefratelli, Brescia, Italy
| | - Sarah Nicolas
- Department of Anatomy and Neuroscience, University College Cork, Ireland
- APC Microbiome Ireland, University College Cork, Ireland
| | - Sebastian Dohm-Hansen
- Department of Anatomy and Neuroscience, University College Cork, Ireland
- APC Microbiome Ireland, University College Cork, Ireland
- INFANT Research Centre, University College Cork, T12 DC4A Cork, Ireland
| | | | | | - Melissa Rosa
- Biological Psychiatry Unit, IRCCS Fatebenefratelli, Brescia, Italy
| | - Karina Hoffmann
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, King’s College London, SE5 9NU London, UK
| | - John F Cryan
- Department of Anatomy and Neuroscience, University College Cork, Ireland
- APC Microbiome Ireland, University College Cork, Ireland
| | - Olivia F O’Leary
- Department of Anatomy and Neuroscience, University College Cork, Ireland
- APC Microbiome Ireland, University College Cork, Ireland
| | - Jane A English
- Department of Anatomy and Neuroscience, University College Cork, Ireland
- INFANT Research Centre, University College Cork, T12 DC4A Cork, Ireland
| | - Aonghus Lavelle
- Department of Anatomy and Neuroscience, University College Cork, Ireland
- APC Microbiome Ireland, University College Cork, Ireland
| | - Cora O’Neill
- APC Microbiome Ireland, University College Cork, Ireland
- School of Biochemistry and Cell Biology, BioSciences Institute, University College Cork, T12 YT20 Cork, Ireland
| | - Sandrine Thuret
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, King’s College London, SE5 9NU London, UK
| | - Annamaria Cattaneo
- Biological Psychiatry Unit, IRCCS Fatebenefratelli, Brescia, Italy
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Yvonne M Nolan
- Department of Anatomy and Neuroscience, University College Cork, Ireland
- APC Microbiome Ireland, University College Cork, Ireland
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18
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Tan S, Chen W, Kong G, Wei L, Xie Y. Peripheral inflammation and neurocognitive impairment: correlations, underlying mechanisms, and therapeutic implications. Front Aging Neurosci 2023; 15:1305790. [PMID: 38094503 PMCID: PMC10716308 DOI: 10.3389/fnagi.2023.1305790] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 11/10/2023] [Indexed: 08/22/2024] Open
Abstract
Cognitive impairments, such as learning and memory deficits, may occur in susceptible populations including the elderly and patients who are chronically ill or have experienced stressful events, including surgery, infection, and trauma. Accumulating lines of evidence suggested that peripheral inflammation featured by the recruitment of peripheral immune cells and the release of pro-inflammatory cytokines may be activated during aging and these conditions, participating in peripheral immune system-brain communication. Lots of progress has been achieved in deciphering the core bridging mechanism connecting peripheral inflammation and cognitive impairments, which may be helpful in developing early diagnosis, prognosis evaluation, and prevention methods based on peripheral blood circulation system sampling and intervention. In this review, we summarized the evolving evidence on the prevalence of peripheral inflammation-associated neurocognitive impairments and discussed the research advances in the underlying mechanisms. We also highlighted the prevention and treatment strategies against peripheral inflammation-associated cognitive dysfunction.
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Affiliation(s)
- Siyou Tan
- Department of Anesthesiology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
- Department of Anesthesiology, Hunan Provincial People’s Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, China
| | - Wenyan Chen
- Department of Anesthesiology, Hunan Provincial People’s Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, China
| | - Gaoyin Kong
- Department of Anesthesiology, Hunan Provincial People’s Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, China
| | - Lai Wei
- Department of Anesthesiology, Hunan Provincial People’s Hospital, The First Affiliated Hospital of Hunan Normal University, Changsha, China
| | - Yubo Xie
- Department of Anesthesiology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
- Guangxi Key Laboratory of Enhanced Recovery after Surgery for Gastrointestinal Cancer, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
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Dong H, Tang X, Ye J, Xiao W. 16S rRNA gene sequencing reveals the effect of fluoxetine on gut microbiota in chronic unpredictable stress-induced depressive-like rats. Ann Gen Psychiatry 2023; 22:27. [PMID: 37537583 PMCID: PMC10398965 DOI: 10.1186/s12991-023-00458-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 07/24/2023] [Indexed: 08/05/2023] Open
Abstract
OBJECTIVES Gut microbiota is relevant to the pathogenesis of mental disorders including depression. This study aimed to investigate the influence of fluoxetine (FLX) on the gut microbiota in rats with Chronic Unpredictable Mild Stresses (CUMS)-induced depression. RESULTS We confirmed that the 28-day CUMS-induced depression rat model. Chronic FLX administration weakly improved depressive-like behaviors in rats. Illumina 16S rRNA gene sequencing on rat feces showed CUMS increased the relative abundance of Firmicutes (60.31% vs. 48.09% in Control, p < 0.05) and Lactobacillus genus (21.06% vs. 6.82% in control, p < 0.05); FLX and CUMS increased Bacilli class (20.00% ~ 24.08% vs. 10.31% in control, p < 0.05). CONCLUSION Collectively, our study showed that both CUMS and FLX changed the compositions of gut microbiota in rats. FLX and CUMS distinctly regulated the gut microbiota in depressed rats.
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Affiliation(s)
- Hui Dong
- Teaching hospital of Yangzhou University, Wutaishan Hospital, Yangzhou, Jiangsu Province, China.
| | - Xiaowei Tang
- Teaching hospital of Yangzhou University, Wutaishan Hospital, Yangzhou, Jiangsu Province, China
| | - Jie Ye
- Teaching hospital of Yangzhou University, Wutaishan Hospital, Yangzhou, Jiangsu Province, China
| | - Wenhuan Xiao
- Teaching hospital of Yangzhou University, Wutaishan Hospital, Yangzhou, Jiangsu Province, China
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20
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Guo X, Zhang X, Tang P, Chong L, Li R. Integration of genome-wide association studies (GWAS) and microbiome data highlights the impact of sulfate-reducing bacteria on Alzheimer's disease. Age Ageing 2023; 52:afad112. [PMID: 37466641 DOI: 10.1093/ageing/afad112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Indexed: 07/20/2023] Open
Abstract
BACKGROUND observational studies have indicated that gut microbiome dysbiosis was associated with Alzheimer's disease (ad). However, the results are largely inconsistent and it remains unknown whether the association is causal in nature. METHODS leveraging observational studies and genome-wide association studies (GWAS) on the gut microbiome in ad patients, we pooled the microbiome data (N = 1,109) to screen the microbiota significantly altered in ad patients and then conducted Mendelian randomisation (MR) study to determine the causal associations between altered microbiota (N = 18,340) and ad using two different ad GWAS datasets (N = 63,926 and N = 472,868) using the inverse variance-weighted (IVW) method. RESULTS the combined effect sizes from observational studies showed that 8 phyla, 18 classes, 22 orders, 37 families, 78 genera and 109 species significantly changed in ad patients. Using the MR analysis, we found that two classes, one order, one family and one genus were suggestively associated with ad consistently in two different GWAS datasets. Both observational studies and MR analysis simultaneously showed that Desulfovibrionales (order) and Desulfovibrionaceae (family), which were mainly implicated in dissimilatory sulfate reduction, were significantly associated with an elevated risk of ad. CONCLUSIONS our findings demonstrated that the abundance of sulfate-reducing bacteria was increased in ad patients, which was causally linked to an increased risk of ad. Further efforts are warranted to clarify the underlying mechanisms, which will provide new insight into the prevention and treatment of ad.
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Affiliation(s)
- Xingzhi Guo
- Department of Geriatric Neurology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, People's Republic of China
- Shaanxi Provincial Clinical Research Center for Geriatric Medicine, Xi'an Shaanxi 710068, People's Republic of China
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an Shaanxi 710072, People's Republic of China
| | - Xin Zhang
- Department of Geriatric Neurology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, People's Republic of China
- Shaanxi Provincial Clinical Research Center for Geriatric Medicine, Xi'an Shaanxi 710068, People's Republic of China
| | - Peng Tang
- Department of Geriatric Neurology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, People's Republic of China
- Shaanxi Provincial Clinical Research Center for Geriatric Medicine, Xi'an Shaanxi 710068, People's Republic of China
| | - Li Chong
- Department of Geriatric Neurology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, People's Republic of China
- Shaanxi Provincial Clinical Research Center for Geriatric Medicine, Xi'an Shaanxi 710068, People's Republic of China
| | - Rui Li
- Department of Geriatric Neurology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, People's Republic of China
- Shaanxi Provincial Clinical Research Center for Geriatric Medicine, Xi'an Shaanxi 710068, People's Republic of China
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an Shaanxi 710072, People's Republic of China
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21
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Cannet C, Bayat A, Frauendienst-Egger G, Freisinger P, Spraul M, Himmelreich N, Kockaya M, Ahring K, Godejohann M, MacDonald A, Trefz F. Phenylketonuria (PKU) Urinary Metabolomic Phenotype Is Defined by Genotype and Metabolite Imbalance: Results in 51 Early Treated Patients Using Ex Vivo 1H-NMR Analysis. Molecules 2023; 28:4916. [PMID: 37446577 DOI: 10.3390/molecules28134916] [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: 04/24/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 07/15/2023] Open
Abstract
Phenylketonuria (PKU) is a rare metabolic disorder caused by mutations in the phenylalanine hydroxylase gene. Depending on the severity of the genetic mutation, medical treatment, and patient dietary management, elevated phenylalanine (Phe) may occur in blood and brain tissues. Research has recently shown that high Phe not only impacts the central nervous system, but also other organ systems (e.g., heart and microbiome). This study used ex vivo proton nuclear magnetic resonance (1H-NMR) analysis of urine samples from PKU patients (mean 14.9 ± 9.2 years, n = 51) to identify the impact of elevated blood Phe and PKU treatment on metabolic profiles. Our results found that 24 out of 98 urinary metabolites showed a significant difference (p < 0.05) for PKU patients compared to age-matched healthy controls (n = 51) based on an analysis of urinary metabolome. These altered urinary metabolites were related to Phe metabolism, dysbiosis, creatine synthesis or intake, the tricarboxylic acid (TCA) cycle, end products of nicotinamide-adenine dinucleotide degradation, and metabolites associated with a low Phe diet. There was an excellent correlation between the metabolome and genotype of PKU patients and healthy controls of 96.7% in a confusion matrix model. Metabolomic investigations may contribute to a better understanding of PKU pathophysiology.
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Affiliation(s)
| | - Allan Bayat
- Kennedy Centre, Center for PKU, 2600 Glostrup, Denmark
| | | | - Peter Freisinger
- Department of Pediatrics, School of Medicine, University of Tübingen, 72074 Tübingen, Germany
| | | | | | - Musa Kockaya
- Private Pediatric Practice, 68307 Mannheim, Germany
| | | | | | - Anita MacDonald
- Dietetic Department, Birmingham Children's Hospital, Birmingham B4 6NH, UK
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22
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Díaz-Camargo E, Hernández-Lalinde J, Sánchez-Rubio M, Chaparro-Suárez Y, Álvarez-Caicedo L, Fierro-Zarate A, Gravini-Donado M, García-Pacheco H, Rojas-Quintero J, Bermúdez V. NHANES 2011-2014 Reveals Decreased Cognitive Performance in U.S. Older Adults with Metabolic Syndrome Combinations. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:5257. [PMID: 37047872 PMCID: PMC10093810 DOI: 10.3390/ijerph20075257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 03/02/2023] [Accepted: 03/08/2023] [Indexed: 06/19/2023]
Abstract
A relationship between metabolic syndrome and cognitive impairment has been evidenced across research; however, conflicting results have been observed. A cross-sectional study was conducted on 3179 adults older than 60 from the 2011-2014 National Health and Nutrition Examination Survey (NHANES) to analyze the relationship between metabolic syndrome and cognitive impairment. In our results, we found that adults with abdominal obesity, high triglycerides, and low HDL cholesterol had 4.39 fewer points in the CERAD immediate recall test than adults without any metabolic syndrome factors [Beta = -4.39, SE = 1.32, 17.75 (1.36) vs. 22.14 (0.76)]. In addition, people with this metabolic syndrome combination exhibited 2.39 fewer points in the CERAD delayed recall test than those without metabolic syndrome criteria [Beta = -2.39, SE = 0.46, 4.32 (0.49) vs. 6.71 (0.30)]. It was also found that persons with high blood pressure, hyperglycemia, and low HDL-cholesterol levels reached 4.11 points less in the animal fluency test than people with no factors [Beta = -4.11, SE = 1.55, 12.67 (2.12) vs. 16.79 (1.35)]. These findings suggest that specific metabolic syndrome combinations are essential predictors of cognitive impairment. In this study, metabolic syndrome combinations that included obesity, fasting hyperglycemia, high triglycerides, and low HDL-cholesterol were among the most frequent criteria observed.
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Affiliation(s)
- Edgar Díaz-Camargo
- Facultad de Ciencias Jurídicas y Sociales, Universidad Simón Bolívar, Cúcuta 540006, Colombia
| | - Juan Hernández-Lalinde
- Facultad de Ciencias Básicas y Biomédicas, Universidad Simón Bolívar, Cúcuta 540006, Colombia
| | - María Sánchez-Rubio
- Facultad de Ciencias Jurídicas y Sociales, Universidad Simón Bolívar, Cúcuta 540006, Colombia
| | - Yudy Chaparro-Suárez
- Facultad de Ciencias Jurídicas y Sociales, Universidad Simón Bolívar, Cúcuta 540006, Colombia
| | - Liseth Álvarez-Caicedo
- Facultad de Ciencias Jurídicas y Sociales, Universidad Simón Bolívar, Cúcuta 540006, Colombia
| | - Alexandra Fierro-Zarate
- Facultad de Ciencias Jurídicas y Sociales, Universidad Simón Bolívar, Cúcuta 540006, Colombia
| | - Marbel Gravini-Donado
- Facultad de Ciencias Jurídicas y Sociales, Universidad Simón Bolívar, Barranquilla 080001, Colombia
| | - Henry García-Pacheco
- Facultad de Medicina, Departamento de Cirugía, Universidad del Zulia, Hospital General del Sur, Dr. Pedro Iturbe, Maracaibo 4004, Venezuela
- Unidad de Cirugía para Obesidad y Metabolismo (UCOM), Maracaibo 4004, Venezuela
| | - Joselyn Rojas-Quintero
- Medicine, Pulmonary, Critical Care, and Sleep Medicine Department, Baylor College of Medicine, Houston, TX 77030, USA
| | - Valmore Bermúdez
- Facultad de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla 080001, Colombia
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23
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Fogelholm N, Leskelä J, Manzoor M, Holmer J, Paju S, Hiltunen K, Roitto HM, Saarela RK, Pitkälä K, Eriksdotter M, Buhlin K, Pussinen PJ, Mäntylä P. Subgingival microbiome at different levels of cognition. J Oral Microbiol 2023; 15:2178765. [PMID: 36844899 PMCID: PMC9946326 DOI: 10.1080/20002297.2023.2178765] [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] [Indexed: 02/22/2023] Open
Abstract
Oral health and declining cognition may have a bi-directional association. We characterized the subgingival microbiota composition of subjects from normal cognition to severe cognitive decline in two cohorts. Memory and Periodontitis (MINOPAR) include 202 home-living participants (50-80 years) in Sweden. Finnish Oral Health Studies in Older Adults (FINORAL) include 174 participants (≥65 years) living in long-term care in Finland. We performed oral examination and assessed the cognitive level with Mini Mental State Examination (MMSE). We sequenced the 16S-rRNA gene (V3-V4 regions) to analyse the subgingival bacterial compositions. The microbial diversities only tended to differ between the MMSE categories, and the strongest determinants were increased probing pocket depth (PPD) and presence of caries. However, abundances of 101 taxa were associated with the MMSE score. After adjusting for age, sex, medications, PPD, and caries, only eight taxa retained the significance in the meta-analyses of the two cohorts. Especially Lachnospiraceae [XIV] at the family, genus, and species level increased with decreasing MMSE. Cognitive decline is associated with obvious changes in the composition of the oral microbiota. Impaired cognition is accompanied with poor oral health status and the appearance of major taxa of the gut microbiota in the oral cavity. Good oral health-care practices require special deliberations among older adults.
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Affiliation(s)
- Nele Fogelholm
- Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki, Finland
| | - Jaakko Leskelä
- Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki, Finland
| | - Muhammed Manzoor
- Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki, Finland
| | - Jacob Holmer
- Division of Periodontology, Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Susanna Paju
- Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki, Finland
| | - Kaija Hiltunen
- Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki, Finland
| | - Hanna-Maria Roitto
- Department of Neurosciences, University of Helsinki, Helsinki, Finland.,Internal medicine and rehabilitation, Division of Geriatrics, Helsinki University Hospital Helsinki, Finland.,Population health unit, Finnish Institute for Health and Welfare, Helsinki, Finland
| | - Riitta Kt Saarela
- Department of Social Services and Health Care, Oral Health Care, Helsinki, Finland
| | - Kaisu Pitkälä
- Department of General Practice and Primary Health Care, University of Helsinki, Helsinki, Finland.,Unit of Primary Health Care, Helsinki University Hospital, Helsinki, Finland
| | - Maria Eriksdotter
- Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden.,Theme Inflammation and Aging, Karolinska University Hospital, Huddinge, Sweden
| | - Kåre Buhlin
- Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki, Finland.,Division of Periodontology, Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Pirkko J Pussinen
- Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki, Finland.,School of Medicine, Institute of Dentistry, University of Eastern Finland, Kuopio, Finland
| | - Päivi Mäntylä
- School of Medicine, Institute of Dentistry, University of Eastern Finland, Kuopio, Finland.,Oral and Maxillofacial Diseases, Kuopio University Hospital, Kuopio, Finland
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24
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Candel S, Tyrkalska SD, Pérez-Sanz F, Moreno-Docón A, Esteban Á, Cayuela ML, Mulero V. Analysis of 16S rRNA Gene Sequence of Nasopharyngeal Exudate Reveals Changes in Key Microbial Communities Associated with Aging. Int J Mol Sci 2023; 24:ijms24044127. [PMID: 36835535 PMCID: PMC9960676 DOI: 10.3390/ijms24044127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/13/2023] [Accepted: 02/14/2023] [Indexed: 02/22/2023] Open
Abstract
Functional or compositional perturbations of the microbiome can occur at different sites, of the body and this dysbiosis has been linked to various diseases. Changes in the nasopharyngeal microbiome are associated to patient's susceptibility to multiple viral infections, supporting the idea that the nasopharynx may be playing an important role in health and disease. Most studies on the nasopharyngeal microbiome have focused on a specific period in the lifespan, such as infancy or the old age, or have other limitations such as low sample size. Therefore, detailed studies analyzing the age- and sex-associated changes in the nasopharyngeal microbiome of healthy people across their whole life are essential to understand the relevance of the nasopharynx in the pathogenesis of multiple diseases, particularly viral infections. One hundred twenty nasopharyngeal samples from healthy subjects of all ages and both sexes were analyzed by 16S rRNA sequencing. Nasopharyngeal bacterial alpha diversity did not vary in any case between age or sex groups. Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes were the predominant phyla in all the age groups, with several sex-associated. Acinetobacter, Brevundimonas, Dolosigranulum, Finegoldia, Haemophilus, Leptotrichia, Moraxella, Peptoniphilus, Pseudomonas, Rothia, and Staphylococcus were the only 11 bacterial genera that presented significant age-associated differences. Other bacterial genera such as Anaerococcus, Burkholderia, Campylobacter, Delftia, Prevotella, Neisseria, Propionibacterium, Streptococcus, Ralstonia, Sphingomonas, and Corynebacterium appeared in the population with a very high frequency, suggesting that their presence might be biologically relevant. Therefore, in contrast to other anatomical areas such as the gut, bacterial diversity in the nasopharynx of healthy subjects remains stable and resistant to perturbations throughout the whole life and in both sexes. Age-associated abundance changes were observed at phylum, family, and genus levels, as well as several sex-associated changes probably due to the different levels of sex hormones present in both sexes at certain ages. Our results provide a complete and valuable dataset that will be useful for future research aiming for studying the relationship between changes in the nasopharyngeal microbiome and susceptibility to or severity of multiple diseases.
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Affiliation(s)
- Sergio Candel
- Grupo de Inmunidad, Inflamación y Cáncer, Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria (IMIB)-Arrixaca, 30120 Murcia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Correspondence: (S.C.); (V.M.)
| | - Sylwia D. Tyrkalska
- Grupo de Inmunidad, Inflamación y Cáncer, Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria (IMIB)-Arrixaca, 30120 Murcia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Fernando Pérez-Sanz
- Instituto Murciano de Investigación Biosanitaria (IMIB)-Arrixaca, 30120 Murcia, Spain
| | - Antonio Moreno-Docón
- Servicio de Microbiología, Hospital Clínico Universitario Virgen de la Arrixaca, 30120 Murcia, Spain
- Grupo de Telomerasa, Cáncer y Envejecimiento, Servicio de Cirugía, Hospital Clínico Universitario Virgen de la Arrixaca, 30120 Murcia, Spain
| | - Ángel Esteban
- Instituto Murciano de Investigación Biosanitaria (IMIB)-Arrixaca, 30120 Murcia, Spain
| | - María L. Cayuela
- Instituto Murciano de Investigación Biosanitaria (IMIB)-Arrixaca, 30120 Murcia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Victoriano Mulero
- Grupo de Inmunidad, Inflamación y Cáncer, Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain
- Instituto Murciano de Investigación Biosanitaria (IMIB)-Arrixaca, 30120 Murcia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Correspondence: (S.C.); (V.M.)
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25
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In vitro prospective healthy and nutritional benefits of different Citrus monofloral honeys. Sci Rep 2023; 13:1088. [PMID: 36658323 PMCID: PMC9852249 DOI: 10.1038/s41598-023-27802-1] [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: 10/22/2022] [Accepted: 01/09/2023] [Indexed: 01/20/2023] Open
Abstract
We studied the total polyphenols, flavonoids, vitamin C, the antioxidant and anti-inflammatory activity of six Citrus monofloral honey, and the in vitro inhibitory effect against cholinesterases and tyrosinase. Finally, we assessed their effect against the biofilm of some pathogenic bacteria. Lime honey showed the best antioxidant activity and the highest content of polyphenols and vitamin C. Lemon and tangerine honey contained almost exclusively flavonoids. Lemon honey better preserved the bovine serum albumin against denaturation (IC50 = 48.47 mg). Honeys inhibited acetylcholinesterase, butyrylcholinesterase, and tyrosinase up to 12.04% (tangerine), 19.11% (bergamot), and 94.1% (lemon), respectively. Lime and clementine honey better inhibited the Listeria monocytogenes biofilm. Bergamot honey acted mainly against the Staphylococcus aureus and Acinetobacter baumannii biofilm; bergamot and tangerine honey inhibited the Pseudomonas aeruginosa biofilm particularly. Bergamot, clementine, and tangerine honey acted against Escherichia coli sessile cell metabolism. This Citrus honey exhibited in vitro prospective health benefits and is applicable for future in vivo studies.
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26
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Sun HL, Feng Y, Zhang Q, Li JX, Wang YY, Su Z, Cheung T, Jackson T, Sha S, Xiang YT. The Microbiome-Gut-Brain Axis and Dementia: A Bibliometric Analysis. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:16549. [PMID: 36554429 PMCID: PMC9779855 DOI: 10.3390/ijerph192416549] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/27/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND Associations between the microbiome-gut-brain axis and dementia have attracted considerable attention in research literature. This study examined the microbiome-gut-brain axis and dementia-related research from a bibliometric perspective. METHODS A search for original research and review articles on the microbiome-gut-brain axis and dementia was conducted in the Web of Science Core Collection (WOSCC) database. The R package "bibliometrix" was used to collect information on countries, institutions, authors, journals, and keywords. VOSviewer software was used to visualize the co-occurrence network of keywords. RESULTS Overall, 494 articles met the study inclusion criteria, with an average of 29.64 citations per article. Corresponding authors of published articles were mainly from China, the United States and Italy. Zhejiang University in China and Kyung Hee University in Korea were the most active institutions, while the Journal of Alzheimer's Disease and Nutrients published the most articles in this field. Expected main search terms, "Parkinson disease" and "chain fatty-acids" were high-frequency keywords that indicate current and future research directions in this field. CONCLUSIONS This bibliometric study helped researchers to identify the key topics and trends in the microbiome-gut-brain axis and dementia-related research. High-frequency keywords identified in this study reflect current trends and possible future directions in this field related to methodologies, mechanisms and populations of interest.
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Affiliation(s)
- He-Li Sun
- Unit of Psychiatry, Department of Public Health and Medicinal Administration, Institute of Translational Medicine, Faculty of Health Sciences, University of Macau, Macao SAR, China
- Centre for Cognitive and Brain Sciences, University of Macau, Macao SAR, China
| | - Yuan Feng
- The National Clinical Research Center for Mental Disorders, Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing 100054, China
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing 100054, China
| | - Qinge Zhang
- The National Clinical Research Center for Mental Disorders, Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing 100054, China
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing 100054, China
| | - Jia-Xin Li
- Centre for Cognitive and Brain Sciences, University of Macau, Macao SAR, China
| | - Yue-Ying Wang
- Centre for Cognitive and Brain Sciences, University of Macau, Macao SAR, China
| | - Zhaohui Su
- School of Public Health, Institute for Human Rights, Southeast University, Nanjing 210096, China
| | - Teris Cheung
- School of Nursing, Hong Kong Polytechnic University, Hong Kong SAR, China
| | - Todd Jackson
- Department of Psychology, University of Macau, Macao SAR, China
| | - Sha Sha
- The National Clinical Research Center for Mental Disorders, Beijing Key Laboratory of Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing 100054, China
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing 100054, China
| | - Yu-Tao Xiang
- Unit of Psychiatry, Department of Public Health and Medicinal Administration, Institute of Translational Medicine, Faculty of Health Sciences, University of Macau, Macao SAR, China
- Centre for Cognitive and Brain Sciences, University of Macau, Macao SAR, China
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27
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Li ZL, Ma HT, Wang M, Qian YH. Research trend of microbiota-gut-brain axis in Alzheimer’s disease based on CiteSpace (2012–2021): A bibliometrics analysis of 608 articles. Front Aging Neurosci 2022; 14:1036120. [DOI: 10.3389/fnagi.2022.1036120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 11/03/2022] [Indexed: 11/23/2022] Open
Abstract
BackgroundRecently, research on the microbiota-gut-brain axis (MGBA) has received increasing attention, and the number of studies related to Alzheimer’s disease (AD) has increased rapidly, but there is currently a lack of summary of MGBA in AD.ObjectiveTo capture research hotspots, grasp the context of disciplinary research, and explore future research development directions.MethodsIn the core dataset of Web of Science, documents are searched according to specific subject words. CiteSpace software is used to perform statistical analysis on measurement indicators such as the number of published papers, publishing countries, institutions, subject areas, authors, cocited journals, and keywords, and to visualize of a network of relevant content elements.ResultsThe research of MGBA in AD has shown an upward trend year by year, and the cooperation between countries is relatively close, and mainly involves the intersection of neuroscience, pharmacy, and microbiology. This research focuses on the relationship between MGBA and AD symptoms. Keyword hotspots are closely related to new technologies. Alzheimer’s disease, anterior cingulate cortex, inflammatory degeneration, dysbiosis, and other research are the focus of this field.ConclusionThe study revealed that the research and development of MGBA in AD rapidly progressed, but no breakthrough has been made in the past decade, it still needs to be closely combined with multidisciplinary technology to grasp the frontier hotspots. Countries should further strengthen cooperation, improve the disciplinary system, and increase the proportion of empirical research in all research.
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28
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Romanescu C, Schreiner TG, Mukovozov I. The Role of Human Herpesvirus 6 Infection in Alzheimer’s Disease Pathogenicity—A Theoretical Mosaic. J Clin Med 2022; 11:jcm11113061. [PMID: 35683449 PMCID: PMC9181317 DOI: 10.3390/jcm11113061] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/24/2022] [Accepted: 05/27/2022] [Indexed: 02/07/2023] Open
Abstract
Alzheimer’s disease (AD), a neurodegenerative disorder generally affecting older adults, is the most common form of dementia worldwide. The disease is marked by severe cognitive and psychiatric decline and has dramatic personal and social consequences. Considerable time and resources are dedicated to the pursuit of a better understanding of disease mechanisms; however, the ultimate goal of obtaining a viable treatment option remains elusive. Neurodegenerative disease as an outcome of gene–environment interaction is a notion widely accepted today; a clear understanding of how external factors are involved in disease pathogenesis is missing, however. In the case of AD, significant effort has been invested in the study of viral pathogens and their role in disease mechanisms. The current scoping review focuses on the purported role HHV-6 plays in AD pathogenesis. First, early studies demonstrating evidence of HHV-6 cantonment in either post-mortem AD brain specimens or in peripheral blood samples of living AD patients are reviewed. Next, selected examples of possible mechanisms whereby viral infection can directly or indirectly contribute to AD pathogenesis are presented, such as autophagy dysregulation, the interaction between miR155 and HHV-6, and amyloid-beta as an antimicrobial peptide. Finally, closely related topics such as HHV-6 penetration in the CNS, HHV-6 involvement in neuroinflammation, and a brief discussion on HHV-6 epigenetics are examined.
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Affiliation(s)
- Constantin Romanescu
- Clinical Section IV, “St. Parascheva” Infectious Disease Hospital, 700116 Iași, Romania
- Correspondence: (C.R.); (T.G.S.)
| | - Thomas Gabriel Schreiner
- Faculty of Medicine, University of Medicine and Pharmacy “Gr. T. Popa”, 700115 Iasi, Romania
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 050474 Bucharest, Romania
- Department of Electrical Measurements and Materials, Faculty of Electrical Engineering and Information Technology, Gheorghe Asachi Technical University of Iasi, 21–23 Professor Dimitrie Mangeron Blvd.,700050 Iasi, Romania
- Correspondence: (C.R.); (T.G.S.)
| | - Ilya Mukovozov
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, BC V6T 1Z4, Canada;
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Soriano S, Curry K, Wang Q, Chow E, Treangen TJ, Villapol S. Fecal Microbiota Transplantation Derived from Alzheimer's Disease Mice Worsens Brain Trauma Outcomes in Wild-Type Controls. Int J Mol Sci 2022; 23:4476. [PMID: 35562867 PMCID: PMC9103830 DOI: 10.3390/ijms23094476] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Revised: 04/14/2022] [Accepted: 04/16/2022] [Indexed: 02/04/2023] Open
Abstract
Traumatic brain injury (TBI) causes neuroinflammation and neurodegeneration, both of which increase the risk and accelerate the progression of Alzheimer's disease (AD). The gut microbiome is an essential modulator of the immune system, impacting the brain. AD has been related with reduced diversity and alterations in the community composition of the gut microbiota. This study aimed to determine whether the gut microbiota from AD mice exacerbates neurological deficits after TBI in control mice. We prepared fecal microbiota transplants from 18 to 24 month old 3×Tg-AD (FMT-AD) and from healthy control (FMT-young) mice. FMTs were administered orally to young control C57BL/6 (wild-type, WT) mice after they underwent controlled cortical impact (CCI) injury, as a model of TBI. Then, we characterized the microbiota composition of the fecal samples by full-length 16S rRNA gene sequencing analysis. We collected the blood, brain, and gut tissues for protein and immunohistochemical analysis. Our results showed that FMT-AD administration stimulates a higher relative abundance of the genus Muribaculum and a decrease in Lactobacillus johnsonii compared to FMT-young in WT mice. Furthermore, WT mice exhibited larger lesion, increased activated microglia/macrophages, and reduced motor recovery after FMT-AD compared to FMT-young one day after TBI. In summary, we observed gut microbiota from AD mice to have a detrimental effect and aggravate the neuroinflammatory response and neurological outcomes after TBI in young WT mice.
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Affiliation(s)
- Sirena Soriano
- Department of Neurosurgery and Center for Neuroregeneration, Houston Methodist Research Institute, 6670 Bertner Avenue, Houston, TX 77030, USA; (S.S.); (E.C.)
| | - Kristen Curry
- Department of Computer Science, Rice University, Houston, TX 77005, USA; (K.C.); (Q.W.); (T.J.T.)
| | - Qi Wang
- Department of Computer Science, Rice University, Houston, TX 77005, USA; (K.C.); (Q.W.); (T.J.T.)
| | - Elsbeth Chow
- Department of Neurosurgery and Center for Neuroregeneration, Houston Methodist Research Institute, 6670 Bertner Avenue, Houston, TX 77030, USA; (S.S.); (E.C.)
| | - Todd J. Treangen
- Department of Computer Science, Rice University, Houston, TX 77005, USA; (K.C.); (Q.W.); (T.J.T.)
| | - Sonia Villapol
- Department of Neurosurgery and Center for Neuroregeneration, Houston Methodist Research Institute, 6670 Bertner Avenue, Houston, TX 77030, USA; (S.S.); (E.C.)
- Department of Neuroscience in Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA
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Bou Zerdan M, Hebbo E, Hijazi A, El Gemayel M, Nasr J, Nasr D, Yaghi M, Bouferraa Y, Nagarajan A. The Gut Microbiome and Alzheimer's Disease: A Growing Relationship. Curr Alzheimer Res 2022; 19:808-818. [PMID: 36578263 DOI: 10.2174/1567205020666221227090125] [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: 07/26/2022] [Revised: 10/03/2022] [Accepted: 10/19/2022] [Indexed: 12/30/2022]
Abstract
Evidence that the gut microbiota plays a key role in the pathogenesis of Alzheimer's disease is already unravelling. The microbiota-gut-brain axis is a bidirectional communication system that is not fully understood but includes neural, immune, endocrine, and metabolic pathways. The progression of Alzheimer's disease is supported by mechanisms related to the imbalance in the gut microbiota and the development of amyloid plaques in the brain, which are at the origin of Alzheimer's disease. Alterations in the composition of the gut microbiome led to dysregulation in the pathways governing this system. This leads to neurodegeneration through neuroinflammation and neurotransmitter dysregulation. Neurodegeneration and disruption of the blood-brain barrier are frontiers at the origin of Alzheimer's disease. Furthermore, bacteria populating the gut microbiota can secrete large amounts of amyloid proteins and lipopolysaccharides, which modulate signaling pathways and alter the production of proinflammatory cytokines associated with the pathogenesis of Alzheimer's disease. Importantly, through molecular mimicry, bacterial amyloids may elicit cross-seeding of misfolding and induce microglial priming at different levels of the brain-gut-microbiota axis. The potential mechanisms of amyloid spreading include neuron-to-neuron or distal neuron spreading, direct blood-brain barrier crossing, or via other cells such as astrocytes, fibroblasts, microglia, and immune system cells. Gut microbiota metabolites, including short-chain fatty acids, pro-inflammatory factors, and neurotransmitters may also affect AD pathogenesis and associated cognitive decline. The purpose of this review is to summarize and discuss the current findings that may elucidate the role of gut microbiota in the development of Alzheimer's disease. Understanding the underlying mechanisms may provide new insights into novel therapeutic strategies for Alzheimer's disease, such as probiotics and targeted oligosaccharides.
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Affiliation(s)
- Maroun Bou Zerdan
- Department of Internal Medicine, SUNY Upstate Medical University, New York, USA
- Department of Hematology and Oncology, Cleveland Clinic Florida, Weston, Florida, USA
| | - Elsa Hebbo
- Faculty of Medicine, American University of Beirut, Beirut 2020, Lebanon
| | - Ali Hijazi
- Faculty of Medicine, American University of Beirut, Beirut 2020, Lebanon
| | - Maria El Gemayel
- Department of Gastroenterology and Hepatology, Faculty of Medicine, Hotel-Dieu de France Hospital, Saint Joseph University, Beirut, Lebanon
| | - Janane Nasr
- Faculty of Medicine, Saint George Hospital, University of Balamand, Beirut, 1100, Lebanon
| | - Dayana Nasr
- Department of Internal Medicine, SUNY Upstate Medical University, New York, USA
| | - Marita Yaghi
- Department of Hematology and Oncology, Cleveland Clinic Florida, Weston, Florida, USA
| | - Youssef Bouferraa
- Department of Internal Medicine, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Arun Nagarajan
- Department of Hematology/Oncology, Cleveland Clinic, Weston, FL, 33331, USA
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