Mycobacterium vaccae: The Bacteria That Makes You Happier and Smarter?

You have probably never heard of this microbe, but you might have inhaled or ingested a few while working in the garden. The bacterium, Mycobacterium vaccae, is thought to act as an antidepressant by stimulating the production of serotonin and norepinephrine in the brain.

Researcher Dorothy Matthews at The Sage Colleges in Troy, New York, and her colleague Susan Jenks conducted an experiment on mice whereby some of the mice were fed the live M. vaccae bacteria, and the others (the control group) were not. It was observed that the mice who had ingested this bacteria were able to find their way through a maze quicker than the other mice, while also demonstrating less anxiety than the control group.

After three weeks, the mice that had been injected with M. vaccae were still faster at the maze than the other mice. However, there was not a huge statistical difference, which shows the effect is temporary.

Another researcher, neuroscientist Christopher Lowry of the University of Bristol in England, wanted to know how M. vaccae might act on the brain to influence mood. He anesthetized six mice and injected powdered (dead and pulverized) M. vaccae bacteria directly into the trachea of each. The mice were then killed and Lowry found there had been an increased production level of serotonin-inducing proteins called cytokines (cell-signaling molecules) in the bodies.

Lowry's research team also dissected the brains of the mice to see if there were any neurons in the brain that might have been activated by the bacteria. They found more serotonin had been produced in the prefrontal cortex of the M. vaccae treated mice and that neurons in a region of the brain called the dorsal raphe nucleus were more active in the bacteria-treated mice than in the others. The part of the raphe that was activated has neurons that connect with other parts of the brain, which regulate mood and cognitive function, such as the hippocampus and prefrontal cortex.

The final test Lowry and his research team conducted was a stress-response test on a different set of mice. In this test, the mice are dropped in water for five minutes to see how long they will swim before they switch to floating. It is known that antidepressants increase swimming behavior in mice, and it was found that M. vaccae had the same effect on the mice as an antidepressant. Those treated with the bacteria swam for four minutes while the control mice only swam, on average, for two and a half minutes before giving up.

I wonder if we will start to see capsules of pure, live M. vaccae become a new probiotic supplement on health food shelves in the future, or hear of psychiatrists recommending them for their depressed and anxious patients. In the meantime, I guess we will just have to take up gardening and walking through the woods to boost our mood.

RESOURCES AND FOR FURTHER READING:

Ingestion of Mycobacterium vaccae decreases anxiety-related behavior and improves learning in mice (abstract of the study)

Is Dirt the New Prozac? (Discover Magazine)

Dirt Can Make You Happy (Horticulture Magazine)

Can Bacteria Make You Smarter? (Science Daily)

Soil Bacteria Might Increase Learning (Scientific American)

How to Get High on Soil (The Atlantic) 

Dorothy Matthews' Ph.D (The Sage College's Faculty Page)

Photography Experiment: Negative Color Photos

Using my old Nokia 6555 flip phone, I took some pictures using one of the camera effects called "negative," which reverses the colors of the thing being photographed. I have found that this makes for some interesting, "artsy" photographs.

 Holding a model of a heart in my hand.

A plastic hand with some liquid inside (in the bottom half).

 Some ferns and other plants.

Leafless tree outside library.

 Railing and stairs outside library.

 Veranda of the library.

 Shadow of potted plant in front of a glass door.

 

 Tree outside library.

Rose mallow flower covered with raindrops.

Here is a picture I took of the same flower, only without the negative effect on, so you can see its true colors:

Amazing Gynandromorphs

Is it a boy or is it a girl? Sometimes it's both!

Animals with bodies that are half male and half female are called "gynandromorphs." This happens when, during cell division, sex chromosomes are divided unevenly (nondisjunction), causing some of the cells to have female sex chromosomes (or a single female sex chromosome) and the other cells to have male sex chromosomes. Some gynandromorphs are bilateral, meaning that the male and female halves of the body are split perfectly down the middle, while other gynandromorphs are mosaic, meaning their male and female cells are scattered unevenly throughout the body. Here are some examples of bilateral gynandromorphs in species that have blatant sexual dimorphism so that you can see clearly which side is male and which side is female at a glance. Quite striking!

Eastern Tiger Swallowtail (Papilio glaucus). The male half is yellow with tiger stripes and the female half is black with an iridescent blue sheen.

 Atlantic blue crab or Chesapeake blue crab (Callinectes sapidus). The male half has the blue claw, the female side has the red claw.

Northern Cardinal (Cardinalis cardinalis). The female side is a "buff-brown" color and the male side is red.

Gynandromorphic chicken. The brown side is female and the side with the white feathers, larger wattle and breast muscles, and a spur on the leg is the male side.

To learn more about these and other gynandromorphs, check out the resources below . . .

RESOURCES:

Gynandromorphs

http://www.daltonstate.edu/galeps/Gyn

Half male, half female butterfly steals the show at Natural History Museum

http://www.guardian.co.uk/science/2011/jul/12/half-male-half-female-butterfly

Photo in the News: Rare He-She Crab Found in Chesapeake

http://news.nationalgeographic.com/news/2005/06/0616_050616_gender_crab.html

Gender-Bending Chickens: Mixed, Not Scrambled

http://scienceblogs.com/grrlscientist/2010/03/12/sex-bird-gynandromorph-somatic/

 Every cell in a chicken has its own male or female identity

http://blogs.discovermagazine.com/notrocketscience/tag/gynandromorph/#.UZgmrkpIEpo

Sketch: Amphioxus and Brittle Star

Here is a sketch I made of an Amphioxus or lancelet, and of a brittle star (class: Ophiuroidea). It was once thought that Amphioxus was the closest living relative of vertebrates, but now it looks like the sea squirt or Tunicate (as evidenced by its larval form) may be the actual closest living relative.

My Amphioxus sketch has the outer skin and muscle on one side "cut away" so that the dorsal nerve cord (darkest line) and the cartilaginous nodocord (directly beneath nerve cord, shaded lighter) can be seen. Also visible are the v-shaped muscle segments (myomeres), gills slits, and gonads (the squarish-round things in a row beneath the gill slits).

The brittle star belongs to the phylum Echinodermata (meaning "spiny skin"), which includes animals such as sea stars (A.K.A."starfish"), basket stars, sea cucumbers, sand dollars, and sea urchins. A brittle star might look like a sea star, but brittle stars and sea stars belong to two different classes. Brittle stars belong to the class Ophiuroidea, while true sea stars belong to the class Asteroidea. So what's the difference? For one thing, they have different means of locomotion. Brittle stars move rapidly by undulating their whole arms in a snake-like motion, while sea stars move slowly using many tiny tube feet on on the underside of their arms. The brittle star's arms have an internal skeleton made up of many vertebral ossicles, which are tiny plates made of calcium carbonate; and the central disk, to which these arms are attached, is clearly defined.

You can see the tube feet, which look like tiny suction cups, on this sea star here:

And here is a picture of a brittle star:

Sketch of Shells: Venus Comb and Miraculous Thatcheria

Here is a sketch I made of two different species of shells. The top right one is called Thatcheria mirabilis or "Miraculous Thatcheria," and the bottom left shell is Murex pecten or "Venus Comb Murex."

Here are what the real shells look like:

First Post

Ideas float about like particles of ionized gases in the nebula of the mind's inner universe, and under the right conditions they fuse together to form clusters of light, like stars that glow faintly or burn brightly in the space of one sentient being's evanescent existence. 

Welcome to Yashi's Nebula!

I am Yashi. Yashi means palm tree in Japanese. I chose this name because I was born in California, which has a lot of palm trees.

Yashi's Nebula is the blog I have created in order to display some of the artwork and creative writing I have been working on throughout the years, as well as share some of my many interests: science, nature, books, languages, and so on.

Your comments and feedback are encouraged. I hope that you enjoy your visit to my blog.