0 The Friday Four

In this edition of the Friday Four, we'll look at the impact of antibiotics on bacteria in dogs' intestines, how fire-bellied toads can help us fight germs, antibiotic cocktails in wasp cocoons, and the effect of stress on your gut flora.

1) Impact of antibiotic treatments on bacteria in the intestines of animals

Source Link: http://www.sciencedaily.com/releases/2010/04/100413081238.htm

ScienceDaily (2010-04-13) -- Recent research from Norway has found that resistance to antibiotics is on the increase in intestinal bacteria in animals as a direct result of antibiotic treatments. The antibiotics also alter the composition of bacteria in the intestines. These discoveries provide more knowledge about the undesirable effect of antibiotic treatments and are of comparative interest as regards other animals and humans.

Comments:

This article is about how within a few days of antibiotic treatment, healthy dogs had a lot of antibiotic resistant E. coli bacteria in their intestines. I shudder to think of the state of my own intestines, after many months of antibiotic use.

I don't know if I really have much to say here, other than to say this: The article quoted nearly 50% of all worldwide antibiotic use is veterinary - I wonder what percentage of that 50% is for factory farms and not for people's pets? Antibiotics should be conserved for pets and people on the rare occasion they need them, and this should have been done all along. 

Now we're facing a crisis situation with antibiotic resistance, one which is most readily observed in our hospitals. And not just our hospitals, but our kitchens...

This was the eye-opener today:

Nationwide study finds US meat and poultry is widely contaminated

Multi-drug-resistant Staph found in nearly 1 in 4 samples, review shows

FLAGSTAFF, Ariz. — April 15, 2011 — Drug-resistant strains of Staphylococcus aureus, a bacteria linked to a wide range of human diseases, are present in meat and poultry from U.S. grocery stores at unexpectedly high rates, according to a nationwide study by the Translational Genomics Research Institute (TGen).

Nearly half of the meat and poultry samples — 47 percent — were contaminated with S. aureus, and more than half of those bacteria — 52 percent — were resistant to at least three classes of antibiotics, according to the study published today in the journal Clinical Infectious Diseases.

More here at the link: http://www.eurekalert.org/pub_releases/2011-04/ttgr-nsf041311.php

Please COOK YOUR FOOD THOROUGHLY.

Other methods of fighting bacterial infections which do not promote resistance must be found.

Which leads us to the next two entries of this Friday Four...

2) Giant fire-bellied toad's brain brims with powerful germ-fighters

Source link: http://www.sciencedaily.com/releases/2011/04/110413121010.htm

ScienceDaily (2011-04-13) -- Frog and toad skins already are renowned as cornucopias of hundreds of germ-fighting substances. Now a new report reveals that the toad brains also may contain an abundance of antibacterial and antiviral substances that could inspire a new generation of medicines.

Comments:

So the "germ-fighting substances" they're talking about are peptides. Many of these peptides were shown to be homologous to hormones and neurotransmitters of mammals. And in recent years it has been shown that these secretions also contain a multitude of antimicrobial peptides.

So in the original research report above, 79 antimicrobial peptides were found to be encoded by 158 cDNA clones from B. maxima (the giant fire bellied toad - see photo to left) and B. microdeladigitora brain cDNA libraries, and of those 79, 20 were the same as ones which had been found before - but 59 were previously unknown and new antimicrobial peptides. These peptides worked against Gram-positive and Gram-negative bacteria and fungi.

Earlier research on these other amphibian-derived peptides have shown that some have activity against mycoplasma infections, HIV, and Staphlococcus aureus.

Antibiotics have been derived from peptides for many years now - some synthetically, like polymyxins and bacitracins - and some are natural, nonsynthetic antibiotics, like melittin (which peptides had to be derived from - melittin itself was not used due to its hemolytic properties) and manuka honey itself.

The latter group rely on observing natural host defenses (as nature’s antibiotics) and the clinical potential of peptides derived from these natural sources - amphibians, insects, mammals, and plants - is something that continues to be studied. These natural antibiotics may replace more of our currently existing selection of antibiotics due to increasing resistance.

Source Reference:
Rui Liu, Huan Liu, Yufang Ma, Jing Wu, Hailong Yang, Huahu Ye, Ren Lai. There are Abundant Antimicrobial Peptides in Brains of Two Kinds ofBombinaToads.Journal of Proteome Research, 2011; 10 (4): 1806 DOI:10.1021/pr101285n

3) Bacteria in wasp antennae produce antibiotic cocktails

Source link: http://www.sciencedaily.com/releases/2011/04/110411194823.htm

ScienceDaily (2011-04-12) -- Bacteria that grow in the antennae of wasps help ward off fungal threats by secreting a 'cocktail' of antibiotics, according to researchers.

Comments:

Who knew that a particular wasp - the beewolf wasp (weird name?) - could have something in common with Lyme disease patients?

These crafty little buggers have their own prophylactic antibiotics right on the outside of their cocoons, so that they are protected from disease when they are transforming from larvae into wasps.

Female beewolf digger wasps cultivate symbiotic Streptomyces bacteria in unique antennal glands and secrete them into their larval brood cells. Then the larvae take up the bacteria and weave them into the cocoon while spinning it. The result is a cocoon which produces at least 9 different antibiotic and antifungal substances.

The article makes a statement that reflects the fact that a number of LLMDs have been ahead of the curve when it comes to treating infections. It states:

"A similar combination prophylaxis (also known as combination therapy) approach is increasingly used in human medicine. Such a treatment exploits the complementary action of two or more antibiotics. It results in a higher efficacy against a broader spectrum of pathogens and is known to prevent micro-organisms from developing resistance to the antibiotic substance."

There is a logic behind combination antibiotic treatment - testing and documenting the efficacy of such combinations goes a long way to supporting long-term antibiotic use where it is needed, especially if lack of resistance can be shown.

The beewolf larva hibernates for several months in its cocoon before the 

adult insect hatches. Antibiotics on the surface of the cocoon, produced by symbionts, guarantee protection against microbial pests during such a protracted developmental stage. The amount of antibiotics was visualized by means of imaging techniques based on mass spectrometry 

(LDI imaging) and merged as pseudocolors onto the cocoon.

Credit: Johannes Kroiss and Martin Kaltenpoth, MPI for Chemical Ecology, Jena (Photomontage).

Source reference:
http://www.sgm.ac.uk/default.cfm

4) Don't Stress - It messes with your gut flora

Source Link: http://researchnews.osu.edu/archive/immunegut.htm

Research out of Ohio State University informs us more about the value of the mind-body connection in affecting our health.

Stress not only sends the human immune system into overdrive - it can also wreak havoc on the trillions of bacteria that work and thrive inside our digestive system. New research suggests that this may be important because those bacteria play a significant role in triggering the innate immune system to stay slightly active, and thereby prepared to quickly spring into action in the face of an infection.

So this is what the study was about:

For two hours daily for six days, an aggressive mouse was placed in a cage of a group of more docile, laid-back mice.

At the end of the string of experiments, blood samples were taken from both stressed animals and matched mice from a control group, along with samples of material from inside each animal’s intestine. The blood samples were analyzed to detect the levels of two biomarkers used to gauge stress – a cytokine called interleukin-6 (IL-6) and a protein called MCP-1 that summons macrophages, or scavenger cells, to the site of an infection.

From the intestinal samples, Bailey’s team could determine the relative proportion of at least 30 types of bacteria residing there.

“We know now that if we knock the population of bacteria down with antibiotics, we don’t have the same innate immune response,” Bailey said. “That showed that the bacteria are involved in the ability of stress to prime the innate immune system.”

Compared to the control mice, the stressed animals showed two marked differences: The proportion of one important type of bacteria in the gut – Bacteroides – fell by 20 to 25 percent while another type – Clostridium – increased a similar amount. Also, levels of the two biomarkers, IL-6 and MCP-1, jumped 10-fold in the stressed mice, compared to controls.

The researchers then treated stressed mice with broad-spectrum antibiotics that could kill as much as 90 percent of the intestinal bacteria for a short period. When they again looked at the two immune biomarkers in the stressed mice, they saw only a doubling of IL-6 and MCP-1 – an increase only one-fifth as much.

Comments:

Stress really affects the immune system - who knew? It's well-known it does, but what isn't known is exactly how it does this - and what can be done other than to get people out of your life who act like aggressive mice.

There is evidence here that stress increases the population of unfriendly and harmful bacteria, and later on, the use of antibiotics knocks down the bacteria needed to prime the immune system.

Healthy stress management and joy are needed in one's life, even while fighting off illness. Especially while fighting off illness.