Powered
byThe microbiome represents diverse viral, bacterial
fungal and other species that live on and within us. They are a part of
us and we are a part of this complex ecosystem. Their proteins bind to
ours, and their metabolism influences ours and vice versa. The
gut microbiome seems to be divided into three major enterotypes Arumugam
et al, 2011. A well balanced microbiome may keep us healthy, while
imbalances may be a factor in causing disease. Certain diseases can be
affected by manipulating the microbiome and some microbiome effects are
catalogued here.
Viruses , bacteria and other pathogens are risk factors in many diseases,
and in several cases can cause disease.These are summarised for several
diseases. Unlike genes, pathogens can be attacked and sometimes eliminated.
The Pubmed icons click to the term + microbiome and some examples are
given: Other Pubmed searches (e.g. probiotic) are programmed: Summaries
of the searches are provided.......................in
progress
PANDAS
Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal
infections
Control of antiviral immunity by pattern recognition and the microbiome.
Pang
and Iwasaki 2011
AIDS
Microbiome Increased Enterobacteriales in HIV-positive subjects: Enterobacteriales
and Bacteroidales levels correlate with duodenal CD4 T-cell depletion
and peripheral CD8 T-cell activation, respectively
Ellis et al, 2011
Yoghurt containing probiotic Lactobacillus rhamnosus and L. reuteri
RC-14 help resolve moderate diarrhea and increase CD4 count in HIV/AIDS
patients Anukam
et al, 2008. see also Irvine
et al, 2010
Bifidobacterium bifidum with Streptococcus thermophilus have immunostimulatory
properties Trois
et al, 2008
Alzheimer's disease
Composition, variability, and temporal stability of the intestinal microbiota
of the elderly. Claesson
et al, 2011
Probiotic
Lactobacillus acidophilus has been reporter to have beneficial effects
Ooi
et al, 2010
Bacterial DNA signatures in carotid atherosclerosis represent both
commensals and pathogens of skin origin (Actinobacteria and members
of the skin microbiome) Renko
et al, 2013.
Arthritis
A large flora is involved, due to sepsis-induced arthritis.
Children with autism had lower levels of species of Bifidobacter and
higher levels of species of Lactobacillus, but similar levels of other
bacteria and yeast Adams
et al, 2011
ss-N-methylamino-L-alanine (BMAA) a toxin that kills dopamine neurones
is produced by some cyanobacteria Vyas
and Weiss, 2009 Chronic polysystemic candidiasis produces acetaldehyde,
which upon reaction with dopamine can produce the neurotoxin Salsolinol
Epp
and Mravec 2006
Caused by childhood infection with Group A beta-hemolytic Streptococci
leading to an autoimmune response that destroys cells in the basal ganglia
Pubmed
Bacteria use some of the same metabolites as us and infection can markedly
affect the levels of important compounds such as cholesterol, glutathione,
tryptophan, methionine S-adenosyl-methionine, and homocysteine. Levels
of these metabolites are modified in many human diseases.
Cholesterol
Glutathione
Glutathione
is an antioxidant and also a potent antiviral
and bactericidal
agent. Viral
, bacterial
or other infections often lower glutathione levels. Certain bacteria
use the host's glutathione to fuel their energy demands. For example,
H.Pylori expresses an enzyme , gamma-Glutamyltranspeptidase that enables
it to metabolise the host’s extracellular glutamine and glutathione
which are hydrolysed to glutamate. This is fed into the H.Pylori Krebs
cycle, resulting in diminished glutathione levels Shibayama
et al, 2007, that can be restored by H.Pylori elimination Oijen
et al, 2001. Glutathione levels are modified in ageing
and in many diseases including cancer,
cystic
fibrosis, atherosclerosis,
inflammatory, immune, metabolic, and neurodegenerative diseases, including
Alzheimer's
diseaseParkinson's
disease and multiple
sclerosis Reviewed in Ballatori
et al, 2009.
Homocysteine
Homocysteine, folate and glutathione metabolism are linked, as shown in
this figure
One
carbon metabolism and the transsulfuration pathway By Michael C Reed
, Rachel L Thomas , Jovana Pavisic , S Jill James , Cornelia M Ulrich
and H Frederik Nijhout (A mathematical model of glutathione metabolism)
[CC-BY-2.0 (www.creativecommons.org/licenses/by/2.0)], via Wikimedia Commons
Many bacteria and other pathogens acquire tryptophan from the host:
A common defense mechanism is the induction of the host's Indoleamine
2,3-dioxygenase (IDO1)
pathway which degrades L-tryptophan to N-formylkynurenine.This will
impact upon tryptophan and 5-hydroxy-tryptophan levels, and ultimately
on serotonin synthesis: The synthesis of Kynurenic acid, an NMDA receptor
antagonist will also be affected as shown in this KEGG pathway (IDO1:
EC number 1.13.11.52) Pubmed e.g. T.Gondii
: This pathway is also affected by viruses: Infection can therefore
impact directly upon key neurotransmitter networks.
From YouTube: For every human cell in your body, there are hundreds or
thousands of bacterial cells. So who is hosting whom? Even though our
on-board microbial hordes—known also as our microbiome—sometimes
threaten and deprive us of our health and our lives, they are central
to our survival and our daily well being.
A discussion brought to you by the DC Science Writers Association and
the USA Science and Engineering Festival filmed on Tuesday, April 17 at
Busboys and Poets on 5th and K Sts., NW, Washington, D.C., that might
convince you to love your microbial partners in life, albeit with a healthy
respect for the ways they can become dangerous. Leading the discussion
is microbiologist Liliana Losada of the J. Craig Venter Institute, an
independent research laboratory in Rockville, Md., that has been greatly
expanding our fundamental knowledge of the microbes in our world; and
Alison O'Brien, former president of the American Society of Microbiology,
professor of microbiology and immunology at the Uniformed Services University
of the Health Sciences, and an expert in the gut bacterium known as E.
coli, a major player in human health, basic science and biotechnology.
Medicine
news headlines provided courtesy of Medical News Today.