Microbiome
10 Apr Probiotics May Influence Schizophrenia Symptoms Through Yeast in Microbiome
MedicalResearch.com Interview with:
Emily G. Severance PhD
Stanley Division of Developmental Neurovirology
Department of Pediatrics
Johns Hopkins University School of Medicine
Baltimore, MD 21287
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Previously, we found that people with schizophrenia and bipolar disorder had an increased susceptibility to Candida albicans yeast infections, which was sex specific and associated with memory deficits. Also in an earlier placebo-controlled probiotic study, we found that although probiotics improved the overall bowel function of people with schizophrenia, there was no effect by this treatment on psychiatric symptoms. Given that C. albicans infections can upset the dynamics of the human microbiome, we decided to re-evaluate the potential benefit of probiotics in the context of a patient’s C. albicans yeast status. Not only was bowel function again enhanced following intake of probiotics, but yeast antibody levels were decreased by this treatment.
Furthermore, psychiatric symptoms were actually improved over time for men receiving probiotics who did not have elevated C. albicans antibodies. Men who were positive for C. albicans exposure, however, consistently presented with worse psychiatric symptoms irrespective of probiotic or placebo treatment.
05 Apr Antibiotics in Pregnancy Increase Children’s Risk of Otitis Media and Ventilation Tubes
MedicalResearch.com Interview with: Hans Bisgaard, MD, DMSc Professor of Pediatrics The Faculty of Health Sciences University of Copenhagen Copenhagen University Hospital, Gentofte Copenhagen, Denmark MedicalResearch.com: What is the background for this study? Response: The consumption of antibiotics is increasing worldwide. Antibiotics alter the maternal bacterial colonization and by vertical transmission this can affect the offspring. An unfavorable microbiome may increase the disease propensity of the offspring. Otitis media is one of the most common infections in early childhood. We hypothesized that antibiotic consumption in pregnancy can increase the children’s risk of otitis media.28 Mar Viral Bacterial Parasites Called Phages Drive Co-Evolution of Gut Microbiome
MedicalResearch.com Interview with: [caption id="attachment_33446" align="alignleft" width="200"]
Dr. Scanlan[/caption]
Dr Pauline Scanlan
Royal Society-Science Foundation Ireland University Research Fellow/APC Faculty,
APC Microbiome Institute, Biosciences,
University College Cork, Éire
MedicalResearch.com: What is the background for this study?
Response: The human gut is host to an incredible diversity of microbes collectively known as the gut microbiome. Each of us has a unique collection of bacterial strains that form part of the gut microbiome. This uniqueness is of potentially crucial importance with respect to host health as we know that differences in bacterial strain diversity within species could have a range of positive or negative consequences for the human host. For example, some strains of a given bacteria are harmless whilst another strain of the same bacterial species could kill you. A classic example of such a difference in strain functionality is exemplified by the gut bacterium Escherichia coli – one strain called E. coli Nissle 1917 is used as a probiotic and another, E. coli O157:H7, has been responsible for a number of deadly food-borne pathogen outbreaks. Therefore a better understanding of what drives bacterial strain diversity is not just fundamental to our understanding of the ecology and evolution of microbes but is also highly relevant for improvements in human health and disease prevention.
19 Mar Protective Bacteria May Reverse Inflammation In Some Forms of IBD
MedicalResearch.com Interview with: Justin E. Wilson, Ph.D On behalf of the authors Research Assistant Professor - Laboratory of Jenny Ting Department of Genetics Lineberger Comprehensive Cancer Center The University of North Carolina at Chapel Hill Chapel Hill, NC 27599 MedicalResearch.com: Could you provide me with some background on this project? Why did you decide to do this research project? What prior work led up to this latest paper? Response: Previous work from our lab and others discovered two major points about NLRP12: a) NLRP12 suppresses inflammation in response to bacterial components b) NLRP12 provides protection against the inflammatory bowel disease colitis and colitis-associated colon cancer (i.e., Nlrp12-defcient mice have greater colon inflammation and inflammation-driven colon cancer). Therefore, we wanted to know if Nlrp12 was regulating inflammation in the colon by responding to the trillions of intestinal microbes collective referred to as the microbiome. Mounting evidence also indicates that the immune system both responds to and influences the composition of the intestinal microbiome during intestinal health and disease, and we hypothesized that NLRP12 could be one of the important immune components during this process. Moreover, we were also interested in this topic because targeting the microbiome to treat inflammatory disorders and other diseases is an attractive method that has many advantages over immune suppression.14 Mar Frozen Fecal Transplant in Pill Form Found To Reverse C. Diff Infection
Posted at 23:27h
in Author Interviews, C. difficile, Gastrointestinal Disease, Microbiome, Transplantation
MedicalResearch.com Interview with:
[caption id="attachment_32899" align="alignleft" width="100"]
Dr. DuPont[/caption]
Dr. H. L. DuPont MD
Director, Center for Infectious Diseases, UTHealth School of Public Health
Mary W. Kelsey Chair in the Medical Sciences, McGovern Medical School at UTHealth
Professor, Department of Epidemiology, Human Genetics and Environmental Sciences
UTHealth School of Public Health
Houston, TX 77030
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Many diseases and disorders are associated with “dysbiosis,” where the intestinal microbiota diversity is reduced. This contributes to disease and to the acquisition of antibiotic resistance. Fecal microbiota transplantation (FMT) is successful in conditions with pure dysbiosis (e.g. C diff infection) and a single dose of FMT is curative in most cases.
23 Feb Cardioprotective Effect of Soy in Japanese May Be Mediated Through Equol
MedicalResearch.com Interview with: [caption id="attachment_32312" align="alignleft" width="200"]
Dr. Sekikawa[/caption]
Akira Sekikawa, Ph.D.
Associate professor of epidemiology
University of Pittsburgh Graduate School of Public Health
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: We found that Japanese men who are able to produce equol—a substance made by some types of “good” gut bacteria when they metabolize isoflavones (micronutrients found in dietary soy)—have lower levels of a risk factor for heart disease than their counterparts who cannot produce it. All monkeys can produce equol, as can 50 to 70 percent of people in Asian countries. However, only 20 to 30 percent of people in Western countries can.
Scientists have known for some time that isoflavones protect against the buildup of plaque in arteries, known as atherosclerosis, in monkeys, and are associated with lower rates of heart disease in people in Asian countries. It was surprising when a large trial of isoflavones in the U.S. didn’t show the beneficial effects on atherosclerosis.
My colleagues and I recruited 272 Japanese men aged 40 to 49 and performed blood tests to find out if they were producing equol. After adjusting for other heart disease risk factors such as high blood pressure, cholesterol, smoking and obesity as well as dietary intake of isoflavones, we found that the equol-producers had 90-percent lower odds of coronary artery calcification, a predictor of heart disease, than the equol non-producers.
11 Feb Intestinal E. coli Linked to Arthritis in Inflammatory Bowel Disease
Posted at 03:19h
in Author Interviews, Gastrointestinal Disease, Infections, Microbiome, Rheumatology, Science
MedicalResearch.com Interview with:
[caption id="attachment_31926" align="alignleft" width="150"]
Dr. Randy Longman[/caption]
Randy Longman, M.D. / Ph.D.
Assistant Professor of Medicine
Jill Roberts Center and Institute for Research in Inflammatory Bowel Disease
Weill Cornell Medicine
Division of Gastroenterology and Hepatology
Joan and Sanford I. Weill Department of Medicine
Department of Microbiology and Immunology
New York, NY 10021
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Inflammatory bowel disease is not limited to intestinal inflammation. Up to 1/3 of patients with active disease suffer from extra-intestinal manifestations.
The most common extra-intestinal manifestations in IBD is joint inflammation or spondyloarthritis. Peripheral joint spondyloarthritis carries a prevalence of 20% in Crohn’s Disease and 10% in Ulcerative Colitis, predominantly affecting joints of the lower limbs. It has long been suggested that gut bacteria can drive this systemic joint inflammation, but microbial targets have not been characterized.
01 Feb Investigational Compound Improves Gut Microbiome Without Long-Term GI Symptoms
MedicalResearch.com Interview with: [caption id="attachment_31681" align="alignleft" width="200"]
Dr. Fernando Azpiroz[/caption]
Fernando Azpiroz, MD, PhD
Chief of the Department of Digestive Diseases
University Hospital Vall d’Hebron
Autonomous University of Barcelona, Spain
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: This open-label, single-arm study, included 26 healthy volunteers who did not have gastrointestinal (GI) symptoms or a history of GI disorders, and were not required to change their diets during treatment. Twenty participants were included in the main evaluation and six were included as control subjects.
Participants in the main study were given HOST-G904 (2.8 g/day) for three weeks, during which time they followed their usual diet. In the evaluation periods (three-day periods immediately before, at the beginning and at the end of the administration), the participants followed a standardized low-fiber diet with one portion of high-fiber foods, at which time the investigators measured the following:
(1) number of daytime gas evacuations for two days;
(2) volume of gas evacuated; and
(3) microbiome composition (as measured by fecal Illumina MiSeq sequencing).
26 Jan Intestinal and Blood-Brain Barrier Alterations Linked to Autism Spectrum Disorders
Posted at 16:42h
in Author Interviews, Autism, Brigham & Women's - Harvard, Gastrointestinal Disease, Microbiome
MedicalResearch.com Interview with:
[caption id="attachment_31521" align="alignleft" width="135"]
Dr. Maria Rosaria Fiorentino[/caption]
Maria Rosaria Fiorentino, PhD
Assistant Professor at Harvard Medical School
Molecular Biologist at Mucosal Immunology and Biology Research Center
Massachusetts General Hospital East
Charlestown, MA 02129-4404
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Autism Spectrum Disorders (ASD) refers to complex neurodevelopmental disorders arising from the interaction of genes and environmental factors. There are no defined mechanisms explaining how environmental triggers can lead to these conditions. One hypothesis based on the gut-brain axis connection suggests that inappropriate antigens trafficking through an impaired intestinal barrier, followed by passage of these antigens through a permissive blood-brain barrier (BBB), can be part of the chain of events leading to the disease.
Many Autism Spectrum Disorders children experience co-morbid medical conditions, including gastrointestinal (GI) dysfunctions whose underlying nature is poorly understood. Several clinical observations describe increased intestinal permeability in ASD with often conflicting findings. Permeability to neuroactive food antigens derived from the partial digestion of wheat (gliadorphins) and cow’s milk (casomorphins) has been reported in ASD. However, while evidence of a permeable gut barrier in ASD is increasingly reported, no information is available concerning a similar breach for the BBB. The BBB is a critical line of defense in the Central Nervous System, limiting the access of circulating solutes, macromolecules, and cells that could negatively impact neuronal activity. Dysfunctions of the BBB have been associated with numerous inflammatory neurologic disorders, such as stroke, epilepsy, multiple sclerosis, Parkinson’s and Alzheimer’s disease.
20 Jan Gut Inflammation & Bacterial Changes Linked to Type 1 Diabetes
MedicalResearch.com Interview with: [caption id="attachment_31395" align="alignleft" width="149"]
Prof Lorenzo Piemonti[/caption]
Prof Lorenzo Piemonti, MD
Professor of Endocrinology
Deputy Director, Diabetes Research Institute (SR-DRI)
Head, Beta Cell Biology Unit
Vita-Salute San Raffaele University,
San Raffaele Scientific Institute
Milano Italy
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: The potential role of gut inflammation and microbiome is becoming a hot topic in the field of diabetes. Several very recent publications report the presence of intestinal abnormalities associated with autoimmune diabetes in both experimental rodent models and patients. We have previously published that, compared to healthy subjects, patients with type 1 diabetes or at high risk of developing type 1 diabetes shows increased intestinal permeability.
Among the factors that may modify the intestinal barrier and impact on its immune activation, the gut microbiota is at present the main suspect. Our study is the first in literature that had the opportunity to analyze the inflammatory profile, the microbiome and their correlation on duodenum biopsies of patients with type 1 diabetes, in comparison with patients with celiac disease and healthy controls. Previous papers pointed out a significant difference in the composition of the stool microflora in subjects with autoimmune diabetes.
A major advancement of our work comes from the direct analysis of small intestine, instead of studies on stool samples. In fact, because of their close functional and spatial relationships, as well as a shared blood supply, it is logical to consider the duodenum and the pancreas correlated. We found big differences among the groups: gut mucosa in diabetes shows a peculiar signature of inflammation, a specific microbiome composition and we also discovered a strong association between some analysed inflammatory markers and specific bacteria genera. We think that our data add an important piece to disentangle the complex pathogenesis of type 1 diabetes and more generally of autoimmune diseases.
09 Dec Uterine Microbiome Plays Key Role in IVF Success
MedicalResearch.com Interview with: [caption id="attachment_30400" align="alignleft" width="155"]
Dr. Carlos Simón[/caption]
Carlos Simón, M.D., Ph. D.
Professor of Obstetrics & Gynecology. Valencia University, Spain
Scientific Director, Igenomix SL.
Adjunct Clinical Professor, Department of Ob/Gyn, Stanford University, CA
Adjunct Professor, Department of Ob/Gyn, Baylor College of Medicine, TX
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: The main findings of this study reside in the concept that the uterine cavity, which has been classically considered as a sterile organ, possess its own microbiome and that the composition of this uterine microbiome have a functional impact on the reproductive outcome of IVF patients.
03 Dec Microbiome Is Major Driver of Recurrent Obesity
MedicalResearch.com Interview with: Dr. Eran Elinav. Principal investigator Immunology Department Weizmann Institute of Science Rehovot, Israel MedicalResearch.com: What is the background for this study? What are the main findings? Response: Recurrent obesity is a very common yet poorly studied and under researched phenomenon. It is well known that many people diet, but then regain the weight they lost and even add more weight. We found that the gut microbiome is a major driver of this enhanced weight regain phenomenon. We found that in the obese state, the microbiome is altered, and these alterations are not reversed upon weight loss. And these alterations are sufficient to drive weight regain, since transferring them to germ-free mice also transferred the enhanced weight regain phenotype. Moreover, we provide three different treatments for this condition: (1) Antibiotics; (2) transfer of bacteria from lean mice; and (3) addition of specific molecules that we found to be lacking in the altered microbiome. All of these treatments cured the mice we tested from enhanced weight regain.21 Nov Without Fiber, Gut Bacteria Begin To Eat Our Intestinal Lining
MedicalResearch.com Interview with: [caption id="attachment_29871" align="alignleft" width="200"]
Dr. Mahesh Desai[/caption]
MedicalResearch.com: What is the background for this study?
Response: Over the last few decades, our intake of dietary fiber has fallen drastically mainly due to the consumption of processed food, which has been connected to increased cases of intestinal diseases including colon cancer and inflammatory bowel disease. The gut microbiota is essential for us as it allows our body to digest dietary fiber contained in fruits and vegetables, that could otherwise not be processed. Changed physiologies and abundances of the gut microbiota following a fiber-deprived diet have been commonly linked to several intestinal diseases. However, the mechanisms behind these connections have remained poorly understood.
28 Sep Excess Zinc May Predispose to C.diff By Altering Gut Microbiome
MedicalResearch.com Interview with: [caption id="attachment_28403" align="alignleft" width="147"]
Dr. Eric P Skaar,[/caption]
Eric P Skaar, Ph.D., MPH
Director, Division of Molecular Pathogenesis
Ernest W. Goodpasture Professor of Pathology
Vice Chair for Basic Research, Department of Pathology, Microbiology, and Immunology
Vanderbilt University School of Medicine
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Nutrient metals are known to be a critical driver of the outcome of host-pathogen interactions, and C. difficile is the most common cause of hospital-acquired infections. C. difficile infection typically occurs following antibiotic-mediated disruption of the healthy microbiome. We were interested in learning how nutrient metals can shape the microbiome and impact the outcome of Clostridium difficile infection.
We found that excess zinc alters the structure of the microbiome and increases the severity of C. difficile infection in mice.
21 Sep Intestinal Microbiome Linked to Obesity and Fat Storage in Children
MedicalResearch.com Interview with: [caption id="attachment_28185" align="alignleft" width="133"]
Dr. Nicola Santoro[/caption]
Nicola Santoro, MD, PhD
Associate Research Scientist in Pediatrics (Endocrinology)
Yale University
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: The study start from previous observations showing an association between the gut microbiota and obesity.
Similarly to what previously described in adults and in children, we found an association between the gut microbiota and obesity. We took a step further and also observed that the gut flora is associated to body fat partitioning (amount of fat in the abdomen). Moreover, we observed that the effect of microbiota could be mediated by the short chain fatty acids a product of gut flora.
18 Aug Circulating TMAO Levels Correlate with Coronary Plaque Vulnerability and Rupture
MedicalResearch.com Interview with: [caption id="attachment_27140" align="alignleft" width="132"]
Dr. Lemin Zheng[/caption]
Lemin Zheng, Ph.D.
Professor, Lab Director, and Principal Investigator The Institute of Cardiovascular Sciences and Institute of Systems Biomedicine
Peking University Health Science Center
Beijing China
MedicalResearch.com: What is the background for this study?
Response: Optical coherence tomography (OCT) has been considered as an ideal tool to characterize accurately atherosclerotic plaques and has potential to detect plaque rupture due to high-resolution (10-20 μm) cross-sectional images of tissue with near infrared light (1-3). Trimethylamine-N-oxide (TMAO) is a gut microbiota-dependent-generated metabolite which is associated with cardiovascular risk by a pathway involving dietary ingestion of nutrients containing trimethylamine, including phosphatidylcholine, choline, and L-carnitine (4-6).
In the gut, choline, betaine and carnitine can be metabolized to trimethylamine (TMA) by gut flora microorganism. And TMA could be further oxidized to a proatherogenic species, TMAO, in the liver by flavin monooxygenases 3 (FMO3)4-6. These risk associations have been repeatedly shown in large observational trials (7-10).
10 Aug Abnormal Microbiome Found in Preterm Infants Who Develop Chronic Lung Disease
[caption id="attachment_26871" align="alignleft" width="139"] Dr. Lal[/caption] MedicalResearch.com Interview with: Charitharth ‘Vivek' Lal, MD Assistant Professor, Division of Neonatal-Perinatal Medicine, Departments of Pediatrics University of Alabama at Birmingham Birmingham, AL 35249-7335 MedicalResearch.com: What is the background for this study? What are the main findings? Response: Airway microbiome of neonates, at birth, has not been studied. Also, association of airway...
19 Jul Phase 2 Trials of Methane Inhibitor Improved Symptoms of Irritable Bowel Syndrome
MedicalResearch.com Interview with: [caption id="attachment_26264" align="alignleft" width="143"]
Dr. Mark Pimentel[/caption]
Mark Pimentel, MD
Associate Professor, Medicine
Director, GI Motility Program
Director, GI Motility Laboratory
Cedars-Sinai
IBS-C Clinical Advisory Board (Chair) at Synthetic Biologics
Los Angeles, CA
MedicalResearch.com: What is the background for this study?
Dr. Pimentel: The SYN-010 program is based on research from my group at Cedars-Sinai Medical Center, and other researchers and collaborators worldwide, investigating the role of intestinal methane production in functional gastrointestinal disorders. Low levels of intestinal methane are a ubiquitous by-product of normal intestinal microbial digestion; however, elevated intestinal methane levels are correlated with decreased intestinal motility and increased symptom severity in patients with irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC).
Methane in humans is produced almost exclusively by the intestinal microorganism Methanobrevibacter smithii (M. smithii). Highest levels of M. smithii are found in the colon; however, overgrowth of M. smithii into the small intestine has also been observed. Previous work from my laboratory demonstrated that methane production by M. smithii in stool samples from IBS-C patients is inhibited by the lactone form of lovastatin. Lovastatin lactone does not appear to eradicate microbial species in the intestine, which should reduce the risk of intestinal dysbiosis and/or the development of microbial resistance.
SYN-010 is a proprietary, modified-release, oral formulation of lovastatin lactone, designed to protect lovastatin lactone from the stomach and release the active ingredient in two different locations of the intestinal tract where the M. smithii reside. SYN-010 exerts its therapeutic effect at the level of the intestinal microbiome and does not require absorption into the systemic circulation or conversion of the active ingredient (lovastatin lactone) to the cholesterol lowering β-hydroxyacid form.
15 Jul Gut Bacteria May Play Role in Rheumatoid Arthritis Activity
MedicalResearch.com Interview with: [caption id="attachment_26144" align="alignleft" width="166"]
Dr. Veena Taneja[/caption]
Veena Taneja, Ph.D
Immunologist
Mayo Clinic
Rochester MN
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Gut bacteria have been suggested to be involved in pathogenesis of rheumatoid arthritis. We used new technology to sequence the bacteria in patients with rheumatoid arthritis and first degree relatives and healthy individuals. We found that patients had lower diversity of bacteria than healthy individuals and the composition of the gut microbiota differed between patients and healthy people. We could identify some bacteria that have expanded in patients though those are generally observed with low numbers in healthy individuals. We could define certain metabolic signatures that associated with microbial profile. For the first time, we could show a direct link between the arthritis-associated bacteria we identified and enhancement of arthritis using a mice carrying the RA-susceptible HLA gene.
06 Jul Bronchoscopy Can Expose Health Care Workers To Pathogens in Aerosol
MedicalResearch.com Interview with: [caption id="attachment_25886" align="alignleft" width="149"]
Dr-Genevieve-Marchand[/caption]
Genevieve Marchand Ph.D., RMCCM SCCM(Env)
Microbiologiste agréée & Biochimiste
Chercheure, Prévention des risques chimiques et biologiques
IRSST
MedicalResearch.com: What is the background for this study?
Response: It is well known that Health Care Workers (HCWs) are at risk of occupationally acquired infections. Some procedures, such as bronchoscopies, are recognized to be high-risk tasks. Most researches that have linked infectious risk to specific task in healthcare settings did not measure the real bioaerosol exposure. Those link where mostly made from epidemiology observations. The aim of this study was to qualify and quantify the real bioaerosol concentrations found during bronchoscopy procedures in order to estimate the true occupational risk.
02 Jul Multiple Sclerosis Patients Have Altered Microbiome That May Benefit From Dietary Changes
MedicalResearch.com Interview with: [caption id="attachment_25768" align="alignleft" width="133"]
Mangalam~Ashu[/caption]
Ashutosh K Mangalam PhD
Assistant Professor
Department of Pathology
University of Iowa
Iowa City, IA
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Every human carries trillions of bacteria in their gut (gut microbiome) and recent advances in research indicate that these tiny passengers play an important role in our overall health maintenance. Having evolved over the time span of millions of years with the gut microbiome, they keep us healthy in multiple ways such as fermentation and absorption of undigested carbohydrates, synthesis of some vitamins, metabolism of bile acids etc.
However, new research suggests that gut microbiome, also regulating our body’s defense system. It is hypothesized that a diverse gut microbiome is good for our health and perturbations in this might predispose us to disease development. Therefore, we asked whether multiple sclerosis (MS) patients have a gut microbiome which is distinct from healthy individuals. We collected fecal samples from MS patients and healthy controls and performed microbiome analysis. I have recently moved to UI but the entire study was completed at Mayo Clinic Rochester. This study involved a big team comprised of neurologist, gastroenterologist, bioinformatician, system biologist and study coordinators. We found that multiple sclerosis patients indeed have a gut microbiome which is different from what is observed in healthy people. We identified certain bacteria which are increased or decreased in the gut of patients with multiple sclerosis compared to healthy controls.
26 Jun Women With Breast Cancer Have Different Bacterial Microbiome in Breasts
MedicalResearch.com Interview with: [caption id="attachment_25539" align="alignleft" width="123"]
Dr. Gregory Reid[/caption]
Gregor Reid, B.Sc. Hons., Ph.D., MBA, ARM, CCM, Dr. HS, FCAHS
Director, Canadian Centre for Human Microbiome and Probiotic Research
Lawson Health Research Institute
London, Ontario, Canada
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Women who breast feed have reduced risk of breast cancer. Human milk has bacteria passed on to the child. These bacteria reach the breast through the nipple and from the gut via the blood. Lactobacilli and Bifidobacteria, beneficial bacteria, grow well in milk. So, I wondered what if women never lactate or breast feed, could bacteria be there? Could bacteria be in the tissue itself and influence whether you got or did not get cancer. Proving there are bacteria in the actual breast tissue itself was an interesting discovery defying previous beliefs.
23 Jun Microbiome Affects the Immune System of Transplanted Organs
MedicalResearch.com Interview with: [caption id="attachment_25456" align="alignleft" width="150"]
Dr. Maria Luisa Alegre[/caption]
Maria-Luisa Alegre, MD, PhD
Professor of medicine
University of Chicago
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Most of the research that investigates why/how transplanted organs are rejected has focused on the genetic disparities between the donor and the recipient. Foreign proteins in the donor organ are recognized by the immune system of the host, which becomes activated to reject the transplanted organ. This is why transplant recipients need to take immunosuppressive medications for the rest of their lives.
Whether environmental factors, in addition to genetic factors, can also affect how the immune system is activated by the transplanted organ is much less understood. In particular, the microbiota, the communities of microbes that live on and in our body, is distinct in each individual and is known to affect the function of the immune system in diseases ranging from autoimmunity to cancer.
Using mouse models of skin and heart transplantation, we investigated if the microbiota was an environmental factor that could affect the speed at which the immune system rejects a transplanted organ.
We found that the microbial communities that colonize the donor and the host fine-tune the function of the immune system and control the strength with which the immune system reacts to a transplanted organ.
21 Jun Model Deepens Understanding of Human Microbiomes
MedicalResearch.com Interview with: Amir Bashan, PhD, and Yang-Yu Liu, PhD Channing Division of Network Medicine Brigham and Women’s Hospital and Harvard Medical School Boston, Massachusetts MedicalResearch.com: What is the background for this study? What are the main findings? Response: We coexist with a vast number of microbes—our microbiota—that live in and on our bodies, and play important roles in human physiology and diseases. Our microbiota is inherently dynamic and changes throughout our lives. The changeability of our microbiota offers opportunities for microbiome-based therapies, e.g. fecal microbiota transplantation (FMT) and probiotic administration, to restore or maintain our healthy microbiota. Yet, our microbiota is also highly personalized and possess unique microbial “fingerprints” in both species assemblages and abundance profiles. This raises fundamental concerns regarding the efficacy and long-term safety of generic microbiome-based therapies. In particular, it is not known whether the underlying ecological dynamics of these communities, which can be parameterized by growth rates, and intra- and inter-species interactions in population dynamics models, are largely host-independent (i.e. universal) or host-specific. If the inter-individual variability reflects host-specific dynamics due to differences in host lifestyle, physiology or genetics, then generic microbiome manipulations may have unintended consequences, rendering them ineffective or even detrimental. In this case, we have to design truly personalized interventions, which need to consider not only the unique microbial state of an individual but also the unique dynamics of the underlying microbial ecosystem. In addition, host-specific microbial dynamics, if they exist, raise a major safety concern for FMT, because although the healthy microbiota are stable in the donor’s gut, they may be shifted to an undesired state in the recipient’s gut. Alternatively, microbial ecosystems of different subjects may exhibit universal dynamics, with the inter-individual variability mainly originating from differences in the sets of colonizing species. We can design general interventions to control the microbial state (in terms of species assemblage and abundance profile) of different individuals.13 Jun Antibiotics Weaken Protective Effect of Breastfeeding on Pediatric Infections and Obesity
MedicalResearch.com Interview with: [caption id="attachment_25125" align="alignleft" width="180"]
Dr. Katri Korpela[/caption]
Dr. Katri Korpela, PhD
University of Helsinki
Helsinki
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Korpela: Previous studies have shown that breastfeeding reduces the frequency of infections in the child and is associated with lower risk of childhood overweight. Conversely, antibiotic use in early life is associated with increased BMI. Both antibiotic use and breastfeeding are known to influence the infant's microbiota. However, these two factors have not been studied together and it was not known whether antibiotic use could modify the beneficial effects of breastfeeding. We collected data on lifetime antibiotic use, breastfeeding duration, and BMI in a group of daycare-attending children aged 2-6 years. We found that the beneficial effects on long breastfeeding, particularly as regards BMI development, were evident only in the children who did not get antibiotics in early life. Antibiotic use before or soon after weaning seemed to eliminate the protection against elevated BMI in preschool age and weaken the protection against infections after weaning.
02 Jun Intestinal Metabolite Associated With Diffuse Atherosclerosis
MedicalResearch.com Interview with: [caption id="attachment_24712" align="alignleft" width="120"]
Dr. W.H.Wilson Tang[/caption]
Dr. W.H. Wilson Tang M.D.
Department of Cellular and Molecular Medicine (NC10)
Cleveland Clinic Lerner Research Institute
Cleveland, Ohio 44195
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Our group has recently described the mechanistic link between intestinal microbe-generated phosphatidylcholine metabolite, trimethylamine N-oxide (TMAO), and the pathogenesis of atherosclerotic coronary artery disease (CAD) and its adverse clinical outcomes. Here in a separate, independent, contemporary cohort of patients undergoing coronary angiography, we demonstrated the association between elevated fasting TMAO levels and quantitative atherosclerotic burden (as measured by SYNTAX and SYNTAX II scores) in stable cardiac patients and is an independent predictor for the presence of diffuse (but not focal) lesion characteristics.
02 Jun Gluten-Free Diet Induces Changes In Gut Microbiome
MedicalResearch.com Interview with: [caption id="attachment_24849" align="alignleft" width="180"]
Ettje Tigchelaar[/caption]
Ettje Tigchelaar MSc
PhD student from department of Genetics
University of Groningen, Groningen
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: A gluten-free diet is used by celiac disease patients to alleviate their symptoms. Previous research in these patients has shown differences in gut microbiota composition when on habitual gluten containing diet (HD) compared to a gluten-free diet (GFD). Recently more and more individuals without celiac disease also started to adopt a gluten-free diet to improve their health and/or control weight. We studied changes in gut microbiota composition in these healthy individuals on a gluten-free diet.
We observed changes in the abundance of specific bacteria, for example the abundance of the bacterium family Veillonellaceae was much lower on a gluten-free diet versus HD, whereas it was higher for the family Clostridiaceae. We also looked at the function of the bacteria in the gut and found that many of those bacteria that changed because of the gluten-free diet played a role in metabolism of starch. This makes sense since starch is like gluten highly present in wheat containing products, thus when eliminating gluten from the diet, the intake of starch also changes and the gut bacteria processing this dietary starch change accordingly.
28 May Bill & Melinda Gates Foundation To Support Study of Microbiome of Infants in Developing Countries
MedicalResearch.com Interview with: [caption id="attachment_24747" align="alignleft" width="350"]
Jennifer Mahony, PhD and Prof Douwe Van Sinderen[/caption]
Jennifer Mahony, PhD and
Prof Douwe Van Sinderen
Dept of Microbiology
University College Cork
Cork, Ireland
MedicalResearch.com Editor's note: Dr Jennifer Mahony & Prof Douwe van Sinderen, of the APC (Alimentary Pharmbiotic Center) Microbiome Institute, University College Cork, Ireland, have received a Grand Challenges Explorations Grant from the Bill & Melinda Gates Foundation to study the microbiota (bacteria and viruses) of infants in developing countries. This study seeks to improve the gut health of infants which could potentially prevent/reduce the estimated 0.8 million infants who die annually in developing countries.
Dr. Mahony & Prof. van Sinderen answered several questions about the upcoming study for the MedicalResearch.com audience.
MedicalResearch.com: What is the background for this study? Would you briefly explain what is meant by a microbiome?
Response: The World Health Organisation promotes exclusive breast-feeding in infants until they are at least 6 months old. Early weaning in developing countries where sanitary conditions may be poor may lead to the introduction of microorganisms such as Shigella, which can cause intestinal infections and in extreme cases may be fatal. 0.8 million infant deaths in developing countries could be avoided annually according to UNICEF if exclusive breast-feeding is continued to the sixth month of life. Our intestinal tracts naturally contain many bacteria, called our microbiota, and the composition of this microbiota may have implications for our health and well-being. Just in the same way that drinking a probiotic drink every day is reported to promote a healthy gut microbiota, we will investigate how bacterial viruses (that specifically infect bacteria and not humans!) can change the gut bacterial population.
22 May Prolonged Antibiotic Therapy May Impact Brain Function
MedicalResearch.com Interview with: [caption id="attachment_24553" align="alignleft" width="180"]
Dr. Susanne Asu Wolf[/caption]
Susanne Asu Wolf PhD
Max-Delbrueck-Center for Molecular Medicine
Berlin, Germany
MedicalResearch.com: What inspired you to research this link between Ly6Chi monocytes, antibiotics and neurogenesis?
Dr. Wolf: As a neuroimmunologist I research the communication between the immune system and the brain. Amongst other research groups we found almost 10 years ago that T cells are needed to maintain brain homeostasis and plasticity, namely neurogenesis. Since only activated T cells enter the brain, we were looking for a mouse model, where immune cells are not activated. My former supervisor Polly Matzinger (NIH), a well-known immunologist, suggested to use germ free mice, born and raised in an isolator without any contact to a pathogen or any bacteria. I did a pilot experiment with the germ free mice, but wanted to get closer to possible applications in humans. Since humans are rarely born and raised in a sterile environment, I was looking for another model. By chance I met with the group of Bereswill and Heimesaat (Berlin, Charite) who provided me with a model, where due to prolonged treatment with an antibiotic cocktail, the microbiota are below detection level and the mice are also virtually germ free. They got me into contact with the second senior author of the paper Ildiko Dunay (University of Magdeburg). Her expertise is the function of Ly6Chi monocytes during infection with malaria or toxoplasmosis.
Now we were ready to investigate the gut-immune-brain axis with the focus on neurogenesis and cognition. Meanwhile the impact of the microbiome on behavior was reported by several research groups using “sterile” germ free mice and I was also curious if we could see similar differences in our antibiotic treated mice.