scholarly journals The impact of the gut microbiome on memory and sleep in Drosophila

2020 ◽  
pp. jeb.233619
Author(s):  
Valeria Silva ◽  
Angelina Palacios-Muñoz ◽  
Zeynep Okray ◽  
Karen L. Adair ◽  
Scott Waddell ◽  
...  

The gut microbiome has been proposed to influence diverse behavioral traits of animals, although the experimental evidence is limited and often contradictory. Here, we make use of the tractability of Drosophila melanogaster for both behavioral analyses and microbiome studies to test how elimination of microorganisms affects a number of behavioral traits. Relative to conventional flies (i.e., with unaltered microbiome), microbiologically-sterile (axenic) flies displayed a moderate reduction in memory performance in olfactory appetitive conditioning and courtship assays. The microbiological status of the flies had small or no effect on anxiety-like behavior (centrophobism) or circadian rhythmicity of locomotor activity, but axenic flies tended to sleep for longer and displayed reduced sleep rebound after sleep deprivation. The latter effects were robust for most tests conducted on both wildtype Canton S and w1118 strains, as well for tests using an isogenized panel of flies with mutations in the period gene, which causes altered circadian rhythmicity. Interestingly, the effect of absence of microbiota on a few behavioral features, most notably instantaneous locomotor activity speed, varied among wild-type strains. Taken together, our findings demonstrate that the microbiome can have subtle but significant effects on specific aspects of Drosophila behavior, some of which are dependent on genetic background.

2017 ◽  
Vol 84 (5) ◽  
Author(s):  
M. Andrea Azcarate-Peril ◽  
Natasha Butz ◽  
Maria Belen Cadenas ◽  
Matthew Koci ◽  
Anne Ballou ◽  
...  

ABSTRACT Salmonella is estimated to cause one million foodborne illnesses in the United States every year. Salmonella -contaminated poultry products are one of the major sources of salmonellosis. Given the critical role of the gut microbiota in Salmonella transmission, a manipulation of the chicken intestinal microenvironment could prevent animal colonization by the pathogen. In Salmonella , the global regulator gene fnr ( f umarate n itrate r eduction) regulates anaerobic metabolism and is essential for adapting to the gut environment. This study tested the hypothesis that an attenuated Fnr mutant of Salmonella enterica serovar Typhimurium (attST) or prebiotic galacto-oligosaccharides (GOS) could improve resistance to wild-type Salmonella via modifications to the structure of the chicken gut microbiome. Intestinal samples from a total of 273 animals were collected weekly for 9 weeks to evaluate the impact of attST or prebiotic supplementation on microbial species of the cecum, duodenum, jejunum, and ileum. We next analyzed changes to the gut microbiome induced by challenging the animals with a wild-type Salmonella serovar 4,[5],12:r:− (Nal r ) strain and determined the clearance rate of the virulent strain in the treated and control groups. Both GOS and the attenuated Salmonella strain modified the gut microbiome but elicited alterations of different taxonomic groups. The attST produced significant increases of Alistipes and undefined Lactobacillus , while GOS increased Christensenellaceae and Lactobacillus reuteri . The microbiome structural changes induced by both treatments resulted in a faster clearance after a Salmonella challenge. IMPORTANCE With an average annual incidence of 13.1 cases/100,000 individuals, salmonellosis has been deemed a nationally notifiable condition in the United States by the Centers for Disease Control and Prevention (CDC). Earlier studies demonstrated that Salmonella is transmitted by a subset of animals (supershedders). The supershedder phenotype can be induced by antibiotics, ascertaining an essential role for the gut microbiota in Salmonella transmission. Consequently, modulation of the gut microbiota and modification of the intestinal microenvironment could assist in preventing animal colonization by the pathogen. Our study demonstrated that a manipulation of the chicken gut microbiota by the administration of an attenuated Salmonella strain or prebiotic galacto-oligosaccharides (GOS) can promote resistance to Salmonella colonization via increases of beneficial microorganisms that translate into a less hospitable gut microenvironment.


2020 ◽  
Author(s):  
Wang Huaqiang ◽  
Ai Jun ◽  
Zhang Jiajuan ◽  
Zheng Wenkai ◽  
Wang Maorong ◽  
...  

Abstract Background: The influence of genotypes on disease progression and clinical outcome of HBV infection is noted. The impact of HBV genotypes on rtA181T/sW172* mutation remains unclear. Patients and Methods: Clinical characteristics of 69 patients with rtA181T/sW172* mutation and 39 patients with rtA181V mutation were analyzed in this study. Fifteen serum specimens with rtA181T/sW172* mutation from different genotypes were collected for cloning and sequence analysis. HBV markers in HepG2 cells encoding different proportions of rtA181T/sW172* mutation and wild type strains were detected in genotype A, B, C and D, respectively.Results: No statistically difference was detected between rtA181T and rtA181V group regarding mean age, sex ratio, liver functions, HBV DNA load and HBeAg positive rate, except for HBsAg level (rtA181T group = 3.07±0.54 lg IU/ml vs rtA181V group = 3.29±0.43 lg IU/ml, P=0.037). Among 69 patients with rtA181T/sW172* mutation, HBV genotypes B and C accounted for 17.0% and 83.0%, respectively. The rate of genotype B was lower in rtA181T group (10.1%) than that in rtA181V group (29.7%), whereas genotype C was higher in rtA181T group (89.9%) than that in rtA181V group (70.3%). HBV rtA181T/sW172* mutant coexisted with wild type strains, accounted for 25% to 90% in all HBV strains. The distribution proportion showed no statistical difference between genotype B and C (59.2%±24.3% vs. 61.2%±19.1% , P=0.86). In transfection experiments, the level of HBV DNA was the highest for genotype B, while HBsAg was expressed in the highest level for genotype A. HBsAg and virus particle were barely detected in the supernatants of rtA181T/sW172* HBV clones in all genotypes. As the proportion of wild type HBV plasmid increased, deficiency of rt181T/sW172* mutation was complemented in all genotypes. No significant difference of the relative expression was found among distinct genotypes (P >0.05).Conclusions: HBV rtA181T/sW172* mutational pattern may be influenced by genotypes, but biological characteristics of this mutation is similar among distinct genotypes.


2021 ◽  
Vol 8 ◽  
Author(s):  
Tianwei Shen ◽  
Kelly M. Hines ◽  
Nathaniel K. Ashford ◽  
Brian J. Werth ◽  
Libin Xu

It has been suggested that daptomycin can be inactivated by lipids released by Staphylococcus aureus and that this effect is antagonized by phenol soluble modulins (PSMs), which bind to the shed lipids. PSM production is regulated by the Agr system, and others have shown that loss of the Agr function enhances S. aureus survival in the presence of daptomycin. Here we assessed the impact of Agr function on daptomycin activity and lipid metabolism under various conditions. Daptomycin activity was evaluated against three sets of isogenic strain series with wild-type or dysfunctional Agr using static daptomycin time-kills over 24 h and against one strain pair using in vitro pharmacokinetic/pharmacodynamic (PK/PD) models simulating clinical daptomycin exposure for 48 h. We performed comprehensive lipidomics on bacterial membranes and the spent media to correlate lipid shedding with survival. In static time-kill experiments, two agr-deficient strains (SH1000- and USA300 LAC ΔagrA) showed improved survival for 8 h compared with their corresponding wild-type strains as seen in previous studies, but this difference did not persist for 24 h. However, four other agr-deficient strains (SH1001 and JE2 agr KOs) did not demonstrate improved survival compared to isogenic wild-type strains at any time in the time-kills. Lipidomics analysis of SH1000, SH1001, and SH1000- strains showed daptomycin exposure increased lipid shedding compared to growth controls in all strains with phosphatidylglycerols (PGs), lysylPGs and cardiolipins predominating. In the cell pellets, PGs and lysylPGs decreased but cardiolipins were unchanged with daptomycin exposure. The shed lipid profiles in SH1001 and SH1000- were similar, suggesting that the inability to resist daptomycin by SH1001 was not because of differences in lipid shedding. In the PK/PD model, the agr mutant SH1000- strain did not show improved survival relative to SH1000 either. In conclusion, inactivation of daptomycin by shed lipids may be dependent on genetic background, the specific agr mutations, or the techniques used to generate these KOs rather than the overall function of the Agr system, and its contribution to daptomycin tolerance seems to be varied, transient, and growth-condition dependent.


2005 ◽  
Vol 17 (9) ◽  
pp. 126 ◽  
Author(s):  
M. J. Boden ◽  
D. J. Kennaway

There is strong epidemiological evidence indicating that disruption of the endogenous circadian rhythms can cause a range of health problems ranging from metabolic and cardiovascular disorders to reproductive failure. Circadian rhythmicity is generated by a suite of genes called ‘clock genes’ that are cyclically expressed in the brain and peripheral tissues. The CLOCK and BMAL1 transcription factors regulate the expression of many genes involved in cell growth, angiogenesis and development. The Bmal1 knockout mouse provides an interesting model to analyse the impact of arrhythmicity on reproductive physiology. Female Bmal1–/– mice show a delay in the onset of puberty (WT = 32.7 d, KO = 38.6 d, n = 8–16). Female Bmal1–/– mice reproductive tissues are significantly smaller than in WT mice (Ovaries –40%, Oviduct –25%, Uterus –60%, n = 10). Female Bmal1–/– mice have essentially normal estrus cycles (cycle length WT = 4.2 d, KO = 4.8 d, n = 8) and are able to ovulate and mate but are unable to establish viable pregnancies. They are as responsive to a standard superovulation protocol as their wild type littermates (ovulated oocytes WT = 23.8, KO=22.8, n = 7–10), suggesting the ovaries are developmentally competent. These results suggest disruption of circadian rhythmicity in the mouse affects fertility at multiple sites. Further investigation into the importance of rhythmicity, particularly post ovulation and post fertilisation is required.


2015 ◽  
Vol 223 (3) ◽  
pp. 173-180 ◽  
Author(s):  
Christina Leibrock ◽  
Michael Hierlmeier ◽  
Undine E. Lang ◽  
Florian Lang

Abstract. The present study explored the impact of Akt1 and Akt3 on behavior. Akt1 (akt1-/-) and Akt3 (akt3-/-) knockout mice were compared to wild type (wt) mice. The akt1-/- mice, akt3-/- mice, and wt mice were similar in most parameters of the open-field test. However, the distance traveled in the center area was slightly but significantly less in akt3-/- mice than in wt mice. In the light/dark transition test akt1-/- mice had significantly lower values than wt mice and akt3-/- mice for distance traveled, number of rearings, rearing time in the light area, as well as time spent and distance traveled in the entrance area. They were significantly different from akt3-/- mice in the distance traveled, visits, number of rearings, rearing time in the light area, as well as time spent, distance traveled, number of rearings, and rearing time in the entrance area. In the O-maze the time spent, and the visits to open arms, as well as the number of protected and unprotected headdips were significantly less in akt1-/- mice than in wt mice, whereas the time spent in closed arms was significantly more in akt1-/- mice than in wt mice. Protected and unprotected headdips were significantly less in akt3-/- mice than in wt mice. In closed area, akt3-/- mice traveled a significantly larger distance at larger average speed than akt1-/- mice. No differences were observed between akt1-/- mice, akt3-/- mice and wt-type mice in the time of floating during the forced swimming test. In conclusion, akt1-/- mice and less so akt3-/ mice display subtle changes in behavior.


2020 ◽  
Author(s):  
Francesca Farina ◽  
Marc Patrick Bennett ◽  
James William Griffith ◽  
Bert Lenaert

Evidence concerning the impact of fear of memory decline on health-related outcomes is limited. To determine the relationship between fear-avoidance of memory decline, quality of life and subjective memory in older adults using a novel scale to measure fear of memory decline. Sixty-seven older adults (59-81 years) completed a 23-item self-report questionnaire designed to capture experiential, cognitive and behavioral components of fear of memory decline, known as the fear and avoidance of memory decline (FAM) scale. Memory performance was assessed using the Wechsler Memory Scale (WMS-IV) and the Memory Failures Scale (MFS). General anxiety was assessed using the Depression, Anxiety and Stress Scales (DASS) and the Geriatric Anxiety Inventory (GAI). Quality of life was assessed using the Older Person’s Quality of Life scale (OPQOL-35). The FAM scale demonstrated good reliability and validity. Three latent factors were observed including: (1) fear-avoidance, (2) problematic beliefs and (3) resilience. After adjusting for age, education, memory performance and general anxiety, higher fear-avoidance predicted lower quality of life (p=.021) and increased memory failures (p=.022). Increased fear of memory decline predicts lower quality of life and subjective memory failures in healthy older adults. Based on these findings, we propose a preliminary fear-avoidance model that explains the development and maintenance of dementia-related functional disability in terms of psychological processes.


2021 ◽  
Vol 9 (5) ◽  
pp. 1062
Author(s):  
Chunye Zhang ◽  
Craig L. Franklin ◽  
Aaron C. Ericsson

The gut microbiome (GM), a complex community of bacteria, viruses, protozoa, and fungi located in the gut of humans and animals, plays significant roles in host health and disease. Animal models are widely used to investigate human diseases in biomedical research and the GM within animal models can change due to the impact of many factors, such as the vendor, husbandry, and environment. Notably, variations in GM can contribute to differences in disease model phenotypes, which can result in poor reproducibility in biomedical research. Variation in the gut microbiome can also impact the translatability of animal models. For example, standard lab mice have different pathogen exposure experiences when compared to wild or pet store mice. As humans have antigen experiences that are more similar to the latter, the use of lab mice with more simplified microbiomes may not yield optimally translatable data. Additionally, the literature describes many methods to manipulate the GM and differences between these methods can also result in differing interpretations of outcomes measures. In this review, we focus on the GM as a potential contributor to the poor reproducibility and translatability of mouse models of disease. First, we summarize the important role of GM in host disease and health through different gut–organ axes and the close association between GM and disease susceptibility through colonization resistance, immune response, and metabolic pathways. Then, we focus on the variation in the microbiome in mouse models of disease and address how this variation can potentially impact disease phenotypes and subsequently influence research reproducibility and translatability. We also discuss the variations between genetic substrains as potential factors that cause poor reproducibility via their effects on the microbiome. In addition, we discuss the utility of complex microbiomes in prospective studies and how manipulation of the GM through differing transfer methods can impact model phenotypes. Lastly, we emphasize the need to explore appropriate methods of GM characterization and manipulation.


2021 ◽  
Vol 22 (2) ◽  
pp. 772
Author(s):  
Javier Conde ◽  
Marlene Schwarzfischer ◽  
Egle Katkeviciute ◽  
Janine Häfliger ◽  
Anna Niechcial ◽  
...  

Environmental and genetic factors have been demonstrated to contribute to the development of inflammatory bowel disease (IBD). Recent studies suggested that the food additive; titanium dioxide (TiO2) might play a causative role in the disease. Therefore, in the present study we aimed to explore the interaction between the food additive TiO2 and the well-characterized IBD risk gene protein tyrosine phosphatase non-receptor type 2 (Ptpn2) and their role in the development of intestinal inflammation. Dextran sodium sulphate (DSS)-induced acute colitis was performed in mice lacking the expression of Ptpn2 in myeloid cells (Ptpn2LysMCre) or their wild type littermates (Ptpn2fl/fl) and exposed to the microparticle TiO2. The impact of Ptpn2 on TiO2 signalling pathways and TiO2-induced IL-1β and IL-10 levels were studied using bone marrow-derived macrophages (BMDMs). Ptpn2LysMCre exposed to TiO2 exhibited more severe intestinal inflammation than their wild type counterparts. This effect was likely due to the impact of TiO2 on the differentiation of intestinal macrophages, suppressing the number of anti-inflammatory macrophages in Ptpn2 deficient mice. Moreover, we also found that TiO2 was able to induce the secretion of IL-1β via mitogen-activated proteins kinases (MAPKs) and to repress the expression of IL-10 in bone marrow-derived macrophages via MAPK-independent pathways. This is the first evidence of the cooperation between the genetic risk factor Ptpn2 and the environmental factor TiO2 in the regulation of intestinal inflammation. The results presented here suggest that the ingestion of certain industrial compounds should be taken into account, especially in individuals with increased genetic risk


Genetics ◽  
2002 ◽  
Vol 162 (1) ◽  
pp. 89-101 ◽  
Author(s):  
Qijun Xiang ◽  
N Louise Glass

AbstractA non-self-recognition system called vegetative incompatibility is ubiquitous in filamentous fungi and is genetically regulated by het loci. Different fungal individuals are unable to form viable heterokaryons if they differ in allelic specificity at a het locus. To identify components of vegetative incompatibility mediated by allelic differences at the het-c locus of Neurospora crassa, we isolated mutants that suppressed phenotypic aspects of het-c vegetative incompatibility. Three deletion mutants were identified; the deletions overlapped each other in an ORF named vib-1 (vegetative incompatibility blocked). Mutations in vib-1 fully relieved growth inhibition and repression of conidiation conferred by het-c vegetative incompatibility and significantly reduced hyphal compartmentation and death rates. The vib-1 mutants displayed a profuse conidiation pattern, suggesting that VIB-1 is a regulator of conidiation. VIB-1 shares a region of similarity to PHOG, a possible phosphate nonrepressible acid phosphatase in Aspergillus nidulans. Native gel analysis of wild-type strains and vib-1 mutants indicated that vib-1 is not the structural gene for nonrepressible acid phosphatase, but rather may regulate nonrepressible acid phosphatase activity.


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