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Brain Parasite Influences Human Personality and Culture

personality parasite

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#1 maxwatt

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Posted 12 December 2011 - 02:45 PM


This got me thinking about how this silent epidemic, as it were, influences US politics, as well as many aspects of peoples' lives. At least 30% of the US population is said to be infected with the T. gondii cysts, and the immune reaction changes dopamine and other neuro-humors' concentrations.

Can the common brain parasite, Toxoplasma gondii, influence human culture?
Kevin D Lafferty*
Western Ecological Research Centre, United States Geological Survey, Marine Science Institute, University of California, Santa Barbara, CA 93106, USA
*(Email: lafferty at lifesci.ucsb.edu).
Received April 21, 2006; Accepted June 6, 2006.

ABSTRACT
The latent prevalence of a long-lived and common brain parasite, Toxoplasma gondii, explains a statistically significant portion of the variance in aggregate neuroticism among populations, as well as in the ‘neurotic’ cultural dimensions of sex roles and uncertainty avoidance. Spurious or non-causal correlations between aggregate personality and aspects of climate and culture that influence T. gondii transmission could also drive these patterns. A link between culture and T. gondii hypothetically results from a behavioural manipulation that the parasite uses to increase its transmission to the next host in the life cycle: a cat. While latent toxoplasmosis is usually benign, the parasite's subtle effect on individual personality appears to alter the aggregate personality at the population level. Drivers of the geographical variation in the prevalence of this parasite include the effects of climate on the persistence of infectious stages in soil, the cultural practices of food preparation and cats as pets. Some variation in culture, therefore, may ultimately be related to how climate affects the distribution of T. gondii, though the results only explain a fraction of the variation in two of the four cultural dimensions, suggesting that if T. gondii does influence human culture, it is only one among many factors

The full paper is HERE: http://www.ncbi.nlm....les/PMC1635495/

Some of the personality changes sound like stereotypes of certain political stereotypes, both left and right:

" both infected men and women have higher levels of guilt-proneness
(they tend to be more apprehensive, self-doubting, worried, guilt
prone, insecure, worrying and self-blaming; Flegr & Hrdy 1994; Flegr
et al. 1996, 2000, 2003)."


sounds like the cliche of a 1950's liberal politician.

Some other traits influenced are cliches from the sterotypical conservative:

...rule-conscious, dutiful, conscientious, conforming, moralistic,
staid and rule-bound)... while infected men have lower ... novelty-seeking (low novelty-
seeking indicates rigid, loyal, stoic, slow-tempered and frugal
personalities)"


Some of the traits are contradictory, but that could be differences in strain of parasite, and severity or locus of infection.

Also possible, that like helminth parasites, we have adapted, so the parasite is needed to normalize biochemistry.

I find it disquieting that so many of us are likely influenced so much by this parasite. Did your family keep a cat or cats as pets when you were a child? Then you are probably infected.

Edited by maxwatt, 12 December 2011 - 02:48 PM.


#2 mikeinnaples

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Posted 12 December 2011 - 03:49 PM

Even if you have the brain parasites, is there anything you can do about it? Disturbing.

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#3 Mind

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Posted 12 December 2011 - 04:41 PM

I grew up with cats. I have cats. Humans have kept cats as pets through the millennia. I read about this a few years ago an posted somewhere here in the forums. I am not worried.

Edited by Mind, 12 December 2011 - 09:44 PM.


#4 Pour_la_Science

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Posted 12 December 2011 - 05:02 PM

Even if you have the brain parasites, is there anything you can do about it? Disturbing.


In fact you can:
From the paper quoted by the OP:

Both anti-toxoplasma drugs and dopamine antagonists normalize the behaviour of infected rats, indicating a neurological mechanism for how T. gondii alters behaviour (http://rspb.royalsoc...t/273/1589/1023)

EDIT: maybe not... the rats in the paper were tested 14 days after contact with T.bondii, so during the infestation phase.

I grew up with cats. I have cats. Humans have kept cats as pets through the millenniums. I read about this a few years ago an posted somewhere here in the forums. I am not worried.

It's the Toxoplasma inside your brain which tell you not to worry...

Edited by Pour_la_Science, 12 December 2011 - 05:39 PM.


#5 Ark

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Posted 12 December 2011 - 07:00 PM

I've heard a high enough dosage of radiation kills Toxoplasma.

#6 maxwatt

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Posted 12 December 2011 - 09:50 PM

Probably would kill the patient too. Problem is not so much live worms, as the cysts containing dormant larva or eggs; the immune system works overtime to keep them dormant, which results in some of the effects noted in the paper above.

#7 Mind

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Posted 12 December 2011 - 09:52 PM

It is not that I don't worry, just that Toxo is extremely low on my scale of things to worry about. Cancer is at the top.

#8 The Immortalist

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Posted 13 December 2011 - 03:00 AM

Is there a test to see if you have the parasite?

#9 Lufega

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Posted 13 December 2011 - 03:14 AM

I'm glad you posted this today. I've been doing some research on this lately. I'm interested in how it can cause bipolar. You don't need to own a cat to get it as T. gondii can pass through the placenta.

The only thing I've found that could potentially kill this parasite is propolis. Propolis can also cross the BBB but I imagine one would need a constant high doses to get any effect. Maybe an intranasal route would be more effective ? Maslinic acid found in olives can also inhibit T. gondii. Olive oil doesn't contain a significant amount of this. Most of it is found in the fruit itself. No idea how much is in olive leaf. Someone even makes an olive leaf nasal spray.

I would focus on securing a diagnosis first, for anyone that considers this a potential problem.

Bipolar disorder seems to run in my family I'm learning. I may also have this (would explain a lot !). However, that diagnosis doesn't do me justice unless I can figure out the source of this disease. Which brings me to this little bastard. I was looking at some brain scans of people with Toxo. The ones that developed lessions were all immunocompromised (HIV, transplants). I haven't found anything to show that immunocompetent patients can develop brain lessions from toxo. I had a cerebral MRI performed and everything looked normal. I have not been tested for toxo though.

#10 maxwatt

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Posted 13 December 2011 - 04:08 AM

There are tests for the active phase of the disease. Treatment is to give anti-malarials. Artemesinin should be particularly effective.

However, most people with healthy immune systems show mild or no symptoms, which are similar to a case of flu or mono. IHowever the long term effect is the formation of thousands of cysts containing spoors of the organism. These can ruptiure, releasing the parasite and leading to reinfection. But a healthy immune system prevents this, but at some cost in resources. And since the brain is usually infected, there are subtle behavioral changes involved. As far as I know, there is no way to eliminate the parasitss' cysts. Perhaps low doses of anti-malarials would help the immune system keep the cysts in check, but this is a guess on my part. Such anti-malarials might include quinine, available in some tonic waters, and artemesinin, which is extracted from an herb.nnIf Lufega or others show suspect infetion wish to eperiment with these, I would hope to hear some report, positive or negative.

One needn't have contact with cats to become infected. Infection comes from contact with animal feces s such as dogs, pigs, cats et al, and dirt,which animals have infected. Handling raw meat can be a source. One can not get it from another person, except one's mother in utero. Good hygene (increasingly ignored in much of the Western world) can prevent infection.

There is a toxicological test to determin if one has ever been infected. IF so, one probably has some number of brain cysts. Brain may be able to determine the degree to which brain cysts are present.

But like mind says, this iprobably a lower order threat to one's survival than something like cancer. I never-the-less find toxoplasmosis infection creepy.
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#11 Lufega

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Posted 13 December 2011 - 05:00 AM

But like mind says, this iprobably a lower order threat to one's survival than something like cancer. I never-the-less find toxoplasmosis infection creepy.


I agree with mind also. It probably wont affect your lifespan but it will really hamper the quality of it. If you get tested for antibodies and they come out positive, combined with changes in your personality then you might want to look into treatment. Convincing your Doc. of this would be hard, I image.

I found a bunch of substances that have anti-toxo activities but olive leaf keep coming out on top. Both Maslinic acid and Oleuropein are effective.

Anti-toxoplasmosis effects of oleuropein isolated from Fraxinus rhychophylla.

Jiang JH, Jin CM, Kim YC, Kim HS, Park WC, Park H.

Source

Department of Infection Biology, Zoonosis Research Center, Wonkwang University School of Medicine, Iksan, Chonbuk 570-749, Korea.

Abstract

Toxoplasmosis is a parasitic disease caused by Toxoplasma gondii, with very few therapeutic treatment options. Typically, the choices for treatment are pyrimethamine and sulfadiazine, however their utility is limited because of drug toxicity and serious side effects. For these reasons, new drugs with lower toxicity are urgently needed. In this study, the compound oleuropein isolated from Fraxinus rhynchophylla showed anti-T. gondii effects in vitro and in vivo. In Madin-Darby bovine kidney cells, the selectivity of oleuropein was 8.9, which was higher than sulfadiazine and pyrimethamine (3.8 and 2.5, respectively). In infected mice, the inhibition ratio of T. gondii in the peritoneal cavity was 55.4% compared to the negative control group after treatment with 300 mg/kg oleuropein. In addition, inhibitory effects on granuloma, apoptosis, necrosis and cyst-formation were shown in sections of spleen and liver. Oleuropein is therefore a potentially useful anti-T. gondii candidate for clinical application.
PMID:19043212 [PubMed - indexed for MEDLINE]Free full text


That rounds out to about 1.5 grams in humans doses. Now, if we could only find an extract standarized for both maslinic acid and oleuropein, that would be great !

Edited by Lufega, 13 December 2011 - 05:02 AM.

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#12 canz

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Posted 13 December 2011 - 06:36 AM

Hmmm. I'm wondering if psychiatrists ever order tests for T. ghondii for patients exhibiting behavioral issues that have had no success with psychotropics, or test patients who have suddenly (within years) have a pattern of behavioral change.

#13 MrHappy

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Posted 13 December 2011 - 12:19 PM

MB, perhaps?
We already know it crosses the BBB well enough and treats malaria. IDK if it would be the same for t.gondi. Since they've used it as a test for the presence of t.gondi, you think they'd have noticed if it was killing the samples.

As for schizophrenics and t.gondi:
http://www.stanleyre...82/Default.aspx

Edit: PS. I hate the latest version of the mobile IPB board reader app... Anyone else using it?

Attached Files


Edited by MrHappy, 13 December 2011 - 12:21 PM.


#14 Lufega

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Posted 13 December 2011 - 07:09 PM

MB, perhaps?
We already know it crosses the BBB well enough and treats malaria. IDK if it would be the same for t.gondi. Since they've used it as a test for the presence of t.gondi, you think they'd have noticed if it was killing the samples.


Maybe used in higher doses than needed for staining ? As in, making your urine and mucus membranes blue.

#15 Lufega

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Posted 13 December 2011 - 07:43 PM

This is a good article on Ergo log.

http://www.ergo-log....asmagondii.html

#16 canz

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Posted 14 December 2011 - 06:33 AM

This is a good article on Ergo log.

http://www.ergo-log....asmagondii.html


Good article, and good site. I've found some interesting things on there. Mostly things that I have known but good for clarification and specifics.

#17 Lufega

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Posted 15 December 2011 - 08:09 AM

Thyme seems to be the most effective treatment for this. It even removes the cysts from the brain. Mice were inoculated, then treated at different times to allow the cysts to disperse. T. Gondii can be found in the brain as early as two hours after infection. The treatment was a single 20 microgram dose of the essential oil and that was enough to eradicate T. Gondii. That's pretty *ucking impressive. One of the active ingredients in thyme is carvacrol which is also found in oregano. However, the study didn't determine which of the components of thyme was responsible for the effect.

I wonder if anyone with schizophrenia or severe bipolar disorder would see any benefits from using thyme extract or drops of thyme essential oil ? I'm certainly going to try it seeing how prevalent toxoplasmosis is.

Parasitol Res. 2010 Jun;107(1):55-8. Epub 2010 Mar 25.
The effect of essential oils from Thymus broussonetii Boiss on transmission of Toxoplasma gondii cysts in mice.

Dahbi A, Bellete B, Flori P, Hssaine A, Elhachimi Y, Raberin H, Chait A, Tran Manh Sung R, Hafid J.

Source

Equipe d'Immuno-Parasitologie et Physiologie, Laboratoire Aliments, Environnement et Santé, Faculté des Sciences et Techniques, Bd. A. El Khattabi, B.P. 549, 40000 Marrakech, Morocco.

Abstract

In this study, we have evaluated the effect of essential oils of Thymus broussonetii Boiss, an endemic plant of Morocco in experimental transmission of Toxoplasma gondii cysts in mice. These oils were obtained by hydrodistillation and were administered to mice at 20 microg/animal orally at the time of infection and for several days thereafter. This resulted in total absence of intracerebral cysts in mice who received the essential oils signifying that these essential oils of thyme have a blocking effect on the appearance of the cysts. In addition, no abnormality was observed in the control mice who received the essential oils of thyme. PMID: 20336317 [PubMed - indexed for MEDLINE]


Full study can be found here: http://www.springerl...76284r032q35p6/

Here's a blog on all things T. gondii: http://toxoplasmapar...e.blogspot.com/

Good night, and good luck.

Edited by Lufega, 15 December 2011 - 08:11 AM.

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#18 Ark

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Posted 15 December 2011 - 10:53 PM

Thyme seems to be the most effective treatment for this. It even removes the cysts from the brain. Mice were inoculated, then treated at different times to allow the cysts to disperse. T. Gondii can be found in the brain as early as two hours after infection. The treatment was a single 20 microgram dose of the essential oil and that was enough to eradicate T. Gondii. That's pretty *ucking impressive. One of the active ingredients in thyme is carvacrol which is also found in oregano. However, the study didn't determine which of the components of thyme was responsible for the effect.

I wonder if anyone with schizophrenia or severe bipolar disorder would see any benefits from using thyme extract or drops of thyme essential oil ? I'm certainly going to try it seeing how prevalent toxoplasmosis is.

Parasitol Res. 2010 Jun;107(1):55-8. Epub 2010 Mar 25.
The effect of essential oils from Thymus broussonetii Boiss on transmission of Toxoplasma gondii cysts in mice.

Dahbi A, Bellete B, Flori P, Hssaine A, Elhachimi Y, Raberin H, Chait A, Tran Manh Sung R, Hafid J.

Source

Equipe d'Immuno-Parasitologie et Physiologie, Laboratoire Aliments, Environnement et Santé, Faculté des Sciences et Techniques, Bd. A. El Khattabi, B.P. 549, 40000 Marrakech, Morocco.

Abstract

In this study, we have evaluated the effect of essential oils of Thymus broussonetii Boiss, an endemic plant of Morocco in experimental transmission of Toxoplasma gondii cysts in mice. These oils were obtained by hydrodistillation and were administered to mice at 20 microg/animal orally at the time of infection and for several days thereafter. This resulted in total absence of intracerebral cysts in mice who received the essential oils signifying that these essential oils of thyme have a blocking effect on the appearance of the cysts. In addition, no abnormality was observed in the control mice who received the essential oils of thyme. PMID: 20336317 [PubMed - indexed for MEDLINE]


Full study can be found here: http://www.springerl...76284r032q35p6/

Here's a blog on all things T. gondii: http://toxoplasmapar...e.blogspot.com/

Good night, and good luck.




wow

great find, what brand of oil does the study use?

#19 Lufega

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Posted 16 December 2011 - 06:45 AM

They made their own. I wonder how these dosages translate to humans ? Do we use 20 micrograms ? Or do we use 20 um per 20 grams of body weight ? In that case, I would have to take about 5 grams of thyme essential oil. Is that even safe ?

edit: I was way off. I think that rounds up to a dose of 100 mg which is just a couple of drops. I'm no good at this. Can someone workout the human dose equivalent ?

Edited by Lufega, 16 December 2011 - 07:22 AM.


#20 MrHappy

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Posted 16 December 2011 - 01:42 PM

Good catch! :)

This looks like a useful product/combination - includes thyme, black walnut, oregano and a number of others:
http://www.resources...t.asp?product=3

#21 Lufega

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Posted 16 December 2011 - 09:25 PM

Good catch! :)

This looks like a useful product/combination - includes thyme, black walnut, oregano and a number of others:
http://www.resources...t.asp?product=3


That looks good actually. You have to keep in mind how much carvacrol it contains. The Thyme oil used in the study (T. broussonetii) is 83% carvacrol. So at 94 kg, I need 104 mg of oil of which 83%, or 86 mg is carvacrol. But again, they're not sure if it's the carvacrol, thymol, or a synergism between the two. I have bottle of oregano oil capsules each containing 7 mg carvacrol. I would need to take 12 softgels to get the right amount. I've used oil of oregano before but not at such a high dose. It always makes me feel like crap. I used another supplement called Tribiotics which contains berberine, artemisinin, citrus seed and black walnut. All are antiparasitic. I could never tolerate more than a couple of pills for a few days. I felt ill on it.

The species of thyme used in the study has different composition from thymus vulgaris, the form most commonly available.

Comparison of volatile constituents, and antioxidant and antibacterial activities of the essential oils ofThymus caucasicus, T. kotschyanus and T. vulgaris.

Abstract

A comparison of the chemical composition, and antioxidant and antibacterial activities of the essential oils obtained from the aerial parts of Thymus caucasicus, T. kotschyanus, and T vulgaris was carried out. The oils, obtained by hydrodistillation, were analyzed by GC and GC/MS. Twenty, 29 and 22 compounds representing 94.8%, 96.6% and 98.2% of the essential oils of T. caucasicus, T. kotschyanus and T. vulgaris, respectively, have been identified. The oil of T. caucasicus was characterized by 1,8-cineol (21.5%), thymol (12.6%), beta-fenchyl alcohol (8.7%), nerolidol (7.8%), terpinolene (7.2%), alpha-pinene (7.0%) and myrcene (6.8%). In the oil of T. kotschyanus, carvacrol (24.4%), beta-caryophyllene (14.5%), gamma-terpinene (12.4%), alpha-phellandrene (10.8%), p-cymene (9.8%) and thymol (6.8%) were the predominant compounds, whereas the main components of T.vulgaris oil were thymol (43.8%), p-cymene (15.2%), germacrene-D (11.7%), terpinolene (3.4%), carvacrol (3.2%), beta-caryophyllene (2.8%) and alpha-thujene (2.2%). In all three plants oil, hydrocarbon monoterpenes predominated over sesquiterpenes. Antioxidant activities were assessed by determining IC50 values in the DPPH radical scavenging assay. Antibacterial activity was determined by measuring minimum inhibitory concentration (MIC) using the broth dilution method. The essential oils of T. caucasicus, T. kotschyanus and T. vulgaris showed free radical scavenging and antibacterial activity.


PMID: 21366065 [PubMed - indexed for MEDLINE]


83.18% in T. broussonetii vs. 3.2% carvacrol in T. vulgaris is a big difference.

From this paper http://www.uicnmed.o...HTM/PDF/p69.pdf

Constituents
The essential oil of Thymus broussonetii from Essaouira region contains thymol (15.2 to 28.9%), carvacrol (10.1 to 30.4%), borneol (14.8 to 19.4 %), p-cymene (3.8 to 15.3%), pinenes (4.1 to 7.8%), camphene 3 to 5.9%), myrcene (2.3 to 2.8%), gamma-terpinene (2.4 to 6.8%). The same species collected in Rabat region was poor in thymol (0.2%) but rich in carvacrol (77.3%). The methanol extract of leaves was chown to contain some flavonoids: luteolin, eriodictyol,
thymonin and glycosides: luteolin-7-O-glucoside, luteolin-3'-O-glucuronide, eriodictyol-7-O-glucoside. Ursolic acid and oleanolic acid were also isolated from the chloroform extract.


I see there are some discrepancies here. The species tested was from the same region as the one used in the study. It's probably best to combine T. vulgaris with oregano oil to get your thymol and carvacrol fix, respectively.

Edited by Lufega, 16 December 2011 - 09:26 PM.


#22 Ark

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Posted 17 December 2011 - 11:10 PM

In Russia Picamilon is prescribed for Nueroinfections according to wikipedia.

I assume Picamilion could have a strong effect against brain parasites.

I think stacking Thyme oil with Picamilion could increase the likelyhood of clearing the Toxoplasma gondii

#23 Lufega

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Posted 17 December 2011 - 11:25 PM

In Russia Picamilon is prescribed for Nueroinfections according to wikipedia.

I assume Picamilion could have a strong effect against brain parasites.

I think stacking Thyme oil with Picamilion could increase the likelyhood of clearing the Toxoplasma gondii


What's the purpose of the picamilion ? To protects neurons from oxidative stress and increase cognitive function ? Or does it have a killing effect ?

#24 Ark

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Posted 18 December 2011 - 01:14 AM

I think RussianBear can explain the answer to this question better.

#25 Lufega

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Posted 18 December 2011 - 06:35 AM

Dietary Lysine can inhibit T. gondii replication by competing with Arginine uptake.

http://www.longecity...post__p__491689



I came across this article today:

http://www.scienceda...10417214159.htm

A substance named L-Lysine may help alleviate schizophrenia symptoms - specifically cognitive deficits. I may try it.


I assumed for a second that Schizophrenia was caused by Toxoplasma Gondii. How would Lysine improve cognitive function in this setting ?

We know from studies with Herpes, that a high concentration of lysine inhibits viral replication and impairs Arginine-reuptake by the kidneys. T. Gondii cannot produce arginine so it needs this from the host. Arginine seems to be important for the survival and replication of t. Gondii as well. When there isn't enough, it converts from the active bradyzoite to the inactive tachyzoite (cyst form).

In other words, supplementing Lysine, lowers arginine concentration and metabolically shuts down T. gondii. With this, the brain can probably resume some of it's normal functions less disturbed. In the cyst form, it can evade immune detection but it can potentially be killed by thyme essential oil.

Impressive.

Toxoplasma gondii lacks the enzymes required for de novo arginine biosynthesis and arginine starvation triggers cyst formation.

Source

Department of Microbiology and Immunology, Dartmouth Medical School, 1 Medical Centre Drive, Lebanon, NH 03756, USA.


Abstract

Two separate carbamoyl phosphate synthetase activities are required for the de novo synthesis of pyrimidines and arginine in most eukaryotes.Toxoplasma gondii is novel in possessing a single carbamoyl phosphate synthetase II gene that corresponds to a glutamine-dependent form required for pyrimidine biosynthesis. We therefore examined arginine acquisition in T. gondii to determine whether the single carbamoyl phosphate synthetase II activity could provide both pyrimidine and arginine biosynthesis. We found that arginine deprivation efficiently blocks the replication of intracellular T.gondii, yet has little effect on long-term parasite viability. Addition of citrulline, but not ornithine, rescues the growth defect observed in the absence of exogenous arginine. This rescue with citrulline is ablated when parasites are cultured in a human citrullinemia fibroblast cell line that is deficient in argininosuccinate synthetase activity. These results reveal the absence of genes and activities of the arginine biosynthetic pathway and demonstrate that T. gondii is an arginine auxotroph. Arginine starvation was also found to efficiently trigger differentiation of replicative tachyzoites into bradyzoites contained within stable cyst-like structures. These same parasites expressing bradyzoite antigens can be efficiently switched back to rapidly proliferating tachyzoites several weeks after arginine starvation. We hypothesise that the absence of gene activities that are essential for the biosynthesis of arginine from carbamoyl phosphate confers a selective advantage by increasing bradyzoite switching during the host response to T.gondii infection. These findings are consistent with a model of host-parasite evolution that allowed host control of bradyzoite induction by trading off virulence for increased transmission.


PMID: 15003493 [PubMed - indexed for MEDLINE]


I would also love to read this study. Pubmed only lists the title. Can anyone get access ? I would imagine that a Lysine deficient diet (which is typically most western, grain based diets) can increase the virulence of a T. gondii infection.

Trop Geogr Med.

1960 Jun;12:180-2.


The effect of a lysine-deficient diet on the course of a chronic Toxoplasma infection.

PMID: 13782343 [PubMed - OLDMEDLINE]



#26 Adan

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Posted 18 December 2011 - 09:51 PM

Hmmm, this is interesting. Dogs, among different animals, maybe involved. Me and my family do have a dog and I was diagnosed with schizophrenia. I will try to get tested for this parasite. Anyone know the specific test for this? Blood test? I have had blood tests after developing schizophrenia and I was not informed of any parasite infection. I will tell my doctor about this parasite and ask about being tested.

#27 Lufega

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Posted 18 December 2011 - 09:55 PM

It's just an igg/igm antibody test. Your Doctor will know what to look for. Please report back any findings !

#28 Lufega

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Posted 27 December 2011 - 11:45 PM

Just got my toxoplasma gondii Igg results: <6.5 IU/mL Negative.

Negative <6.5
Equivocal 6.5 - 7.9
Positive >7.9

#29 Rational Madman

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Posted 17 January 2012 - 10:50 PM

The evidence suggests that a number of pathogens can trigger the presentation of the aforementioned symptoms---usually herpesviruses. So I don't think we should get too caught up with trying to reduce the problem to a single cause, because such a conclusion might lead to too many false negatives in diagnostic evaluations. Instead, I think we can logically conclude that there is a pathogenic involvement, and that a broad spectrum approach that involves antibiotic, antihelmintic, and antiviral agents should be used.

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#30 Rational Madman

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Posted 17 January 2012 - 11:01 PM

This got me thinking about how this silent epidemic, as it were, influences US politics, as well as many aspects of peoples' lives. At least 30% of the US population is said to be infected with the T. gondii cysts, and the immune reaction changes dopamine and other neuro-humors' concentrations.

Can the common brain parasite, Toxoplasma gondii, influence human culture?
Kevin D Lafferty*
Western Ecological Research Centre, United States Geological Survey, Marine Science Institute, University of California, Santa Barbara, CA 93106, USA
*(Email: lafferty at lifesci.ucsb.edu).
Received April 21, 2006; Accepted June 6, 2006.

ABSTRACT
The latent prevalence of a long-lived and common brain parasite, Toxoplasma gondii, explains a statistically significant portion of the variance in aggregate neuroticism among populations, as well as in the ‘neurotic’ cultural dimensions of sex roles and uncertainty avoidance. Spurious or non-causal correlations between aggregate personality and aspects of climate and culture that influence T. gondii transmission could also drive these patterns. A link between culture and T. gondii hypothetically results from a behavioural manipulation that the parasite uses to increase its transmission to the next host in the life cycle: a cat. While latent toxoplasmosis is usually benign, the parasite's subtle effect on individual personality appears to alter the aggregate personality at the population level. Drivers of the geographical variation in the prevalence of this parasite include the effects of climate on the persistence of infectious stages in soil, the cultural practices of food preparation and cats as pets. Some variation in culture, therefore, may ultimately be related to how climate affects the distribution of T. gondii, though the results only explain a fraction of the variation in two of the four cultural dimensions, suggesting that if T. gondii does influence human culture, it is only one among many factors

The full paper is HERE: http://www.ncbi.nlm....les/PMC1635495/

Some of the personality changes sound like stereotypes of certain political stereotypes, both left and right:

" both infected men and women have higher levels of guilt-proneness
(they tend to be more apprehensive, self-doubting, worried, guilt
prone, insecure, worrying and self-blaming; Flegr & Hrdy 1994; Flegr
et al. 1996, 2000, 2003)."


sounds like the cliche of a 1950's liberal politician.

Some other traits influenced are cliches from the sterotypical conservative:

...rule-conscious, dutiful, conscientious, conforming, moralistic,
staid and rule-bound)... while infected men have lower ... novelty-seeking (low novelty-
seeking indicates rigid, loyal, stoic, slow-tempered and frugal
personalities)"


Some of the traits are contradictory, but that could be differences in strain of parasite, and severity or locus of infection.

Also possible, that like helminth parasites, we have adapted, so the parasite is needed to normalize biochemistry.

I find it disquieting that so many of us are likely influenced so much by this parasite. Did your family keep a cat or cats as pets when you were a child? Then you are probably infected.


I too suspect that pathogens might play a role in social and political behavior, but I think external stressors are needed for the pathogen to thrive. A recession would be such an example, which likely causes immunocompromising stress, and helps lead to the activation of dormant pathogens. In situations of exceptionally acute stress, like 1920s Germany, multiple pathogens could've been activated in a large percentage of the population---which might explain how the behavior of a significant portion of Germany's inhabitants was radically changed for the worse.

Edited by Rational Madman, 18 January 2012 - 02:18 AM.






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