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Hi ,

Thanks for the info! Could you sum this info up if you have time? I just can't seem to understand the point. I am just not good at reading these technical terms.

Lori A.

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New PSC leads

From: The Liver Meeting® 2008 (http://www.aasld. org/Pages/ Default.aspx)

Enteric dendritic cells determine recruitment of mucosal T cells to the liver in Primary Sclerosing Cholangitis B. Eksteen1; S. M. Curbishley1; A. Aspinall2; D. H. 1 1. Liver Research Group, University Of Birmingham, Birmingham, West Midlands, United Kingdom. 2. Foothills Hospital, University of Calgary, Calgary, AB, Canada. Background and aims: Lymphocytes primed by dendritic cells (DCs) in the gut express the gut-homing receptors CCR9 and a4ß7 which recognise CCL25 and MADCAM-1 expressed in the intestine. In mice this programming is dependent on retinoic acid and subject to plasticity to allow the development of T-cells that can react to antigen at different anatomical sites. In humans tissue-specificity is lost in primary sclerosing cholangitis (PSC), an extra-intestinal manifestation of inflammatory bowel disease, when ectopic expression of MADCAM-1 and CCL25 in the liver promotes recruitment of CCR9 and a4ß7+ T

cells to the liver. This led us to investigate whether the ability to imprint CCR9 and a4ß7 in humans is restricted to intestinal DCs and dependent on retinoic acid and thereby to determine whether T cells that infiltrate the liver in PSC are primed in the gut or liver.

Methods: DCs isolated from human gut, liver or portal lymph nodes were used to activate CD8 T-cells in the presence or absence of retinoic acid. Imprinting of CCR9 and a4ß7 and functional migration responses were determined and cross-over activation protocols used to assess plasticity of gut-homing.

Results: Gut-derived DCs imprinted functional CCR9 and a4ß7 expression on T-cells whereas DCs from other human tissues including the liver and portal lymph nodes of patients with PSC were unable to do so. Imprinting was retinoic acid-dependent and demonstrated plasticity.

Conclusions: Imprinting and plasticity of gut homing human CD8 T-cells requires primary activation or reactivation by gut DCs and is retinoic acid dependent. The inability of liver DCs to imprint gut-tropism implies that a4ß7+CCR9+ T cell that infiltrate the liver in PSC are primed in the gut and provides further evidence that gut-derived lymphocytes contribute to inflammation in the PSC liver.

____________ _________ _________ __

Factors responsible for MAdCAM-1 expression in human liver: potential targets for treatment of inflammatory bowel diseases (IBD) and its manifestations in the liver. E. Liaskou1; C. J. Weston1; B. Eksteen1; P. F. Lalor1; D. H. 1 1. Liver Labs, Institute of Biomedical Research, Birmingham, United Kingdom. MAdCAM-1 is a tissue-specific endothelial adhesion molecule which orchestrates immune responses in the gut by promoting the rolling and firm adhesion of lymphocytes on mucosal endothelium. Recent studies report the expression of MAdCAM-1 on liver endothelium in patients with primary sclerosis cholangitis and autoimmune hepatitis complicating inflammatory bowel disease (IBD). Understanding the factors that drive hepatic expression of MAdCAM-1 will thus elucidate the pathogenesis of these diseases. Liver endothelium expresses a cell surface enzyme, AOC-3 or vascular adhesion protein-1 (VAP-1), which is also an adhesion

molecule. We have shown that activation of VAP-1 by substrates including methylamine, an aliphatic amine ingested from food and wine, drives NFkB-dependent activation of ICAM-1 and VCAM-1. In the current study we tested the hypothesis that VAP-1 enzyme activity can synergise with proinflammatory signals to drive MAdCAM-1 expression on liver endothelium.METHODS: We stimulated human sinusoidal endothelial cells (HSEC) and umbilical vein endothelial cells (HUVEC) with cytokines including TNFa (20ng/ml), rVAP-1 (50ng/ml) and methylamine (50µM) and then with combinations of TNFa plus methylamine. MAdCAM-1 expression was examined by ELISA, RT-PCR and Western blotting and function investigated in a flow-based adhesion assay, in which it was tested under physiological shear stress (0.05PA) the ability of lymphocytes expressing the MAdCAM-1 receptor a4ß7 to bind MAdCAM-1 induced in activated HSEC was tested. MadCAM-1 and a4ß7 were blocked with antibodies,

P1 and ACT1 respectively.RESULTS: We detected for the first time levels of MAdCAM-1 mRNA and protein in untreated HSEC and HUVEC, though the encoded protein was inactive to support adhesion. However, treatment with methylamine and methylamine plus TNFa induced expression of functional MAdCAM-1 that supported significant levels of lymphocyte adhesion under flow. Blocking studies confirmed this adhesion was a4ß7-dependent.CONCLUSION: We report induction of ectopic MAdCAM-1 on human hepatic endothelium by the dietary amine constituent methylamine and suggest that methylamine in the portal blood of patients with IBD might act as an environmental factor to drive hepatic MAdCAM-1 expression resulting in the recruitment of disease-associated mucosal T cells in PSC.

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Hi Lori;

I'll do my best to try to explain this information, although it is

awfully complicated, and I might have to simplify things a lot. Here

goes ....

In the gut there are lymphoid tissues that produce immune cells whose

main job is to take care of various foreign organisms (e.g.

bacteria). The gut lymphoid tissue produces dendritic cells which

secrete various substances that activate and educate T cells. For

instance, the dendritic cells produce retinoic acid (from vitamin A)

that tells the T cells to produce molecules on their surfaces that

act as zip-codes, and which instruct the T cells where they should be

delivered in the body. CCR9 and a4ß7 are the zip-codes on the T

cells. The T cells then go roaming around the body until they find

their correct mail-box. They are usually delivered to cells that

express MADCAM-1 and CCL25, and these are usually found only in the

gut. In this way the T cells are delivered (like a piece of mail) to

the correct address, where they then can do their job of

orchestrating the neutralization or killing of invading organisms in

the gut.

In PSC, however, it seems that the mail box (MAdCAM-1 and CCL25) is

incorrectly expressed in the liver, so the T cells go to the liver

instead of to the gut, and cause inflammation in the liver. It

appears that only the dendritic cells in the gut do the " zip-code "

imprinting of the T cells. But it's still not clear to me whether

something else may be going awry with this " zip-code " imprinting

system or mail delivery system? A disgruntled postal worker?

The interesting new " lead " is that the dietary substance methylamine

is an inducer of MAdCAM-1 in the liver, suggesting that this dietary

substance may be a key to why the mail-box is incorrectly expressed

in the liver in PSC patients? Increased expression of MAdCAM-1 caused

by methylamine allows the T cells (mail) to be delivered to the wrong

address!

Because a certain type of T cells called Th17 cells are now being

implicated in inflammatory bowel disease, autoimmune hepatitis and

primary biliary cirrhosis (see the other abstracts posted earlier) it

will be interesting to see if such Th17 cells are being delivered

inappropriately to the liver in PSC?

The Th17 cells are very pro-inflammatory. Their production in the gut

can be inhibited by retinoic acid (vitamin A). There is also some

evidence that production of Th17 cells can be inhibited by

eicosapentaenoic acid (EPA); a component of fish oils. They can also

be suppressed by anti-inflammatory regulatory T cells (Tregs).

Several of the susceptibility genes involved in inflammatory bowel

disease seem to be involved in Th17 cell production and impairments

in Tregs.

Best regards,

Dave

(father of (23); PSC 07/03; UC 08/03)

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Share on other sites

Hi Lori;

I'll do my best to try to explain this information, although it is

awfully complicated, and I might have to simplify things a lot. Here

goes ....

In the gut there are lymphoid tissues that produce immune cells whose

main job is to take care of various foreign organisms (e.g.

bacteria). The gut lymphoid tissue produces dendritic cells which

secrete various substances that activate and educate T cells. For

instance, the dendritic cells produce retinoic acid (from vitamin A)

that tells the T cells to produce molecules on their surfaces that

act as zip-codes, and which instruct the T cells where they should be

delivered in the body. CCR9 and a4ß7 are the zip-codes on the T

cells. The T cells then go roaming around the body until they find

their correct mail-box. They are usually delivered to cells that

express MADCAM-1 and CCL25, and these are usually found only in the

gut. In this way the T cells are delivered (like a piece of mail) to

the correct address, where they then can do their job of

orchestrating the neutralization or killing of invading organisms in

the gut.

In PSC, however, it seems that the mail box (MAdCAM-1 and CCL25) is

incorrectly expressed in the liver, so the T cells go to the liver

instead of to the gut, and cause inflammation in the liver. It

appears that only the dendritic cells in the gut do the " zip-code "

imprinting of the T cells. But it's still not clear to me whether

something else may be going awry with this " zip-code " imprinting

system or mail delivery system? A disgruntled postal worker?

The interesting new " lead " is that the dietary substance methylamine

is an inducer of MAdCAM-1 in the liver, suggesting that this dietary

substance may be a key to why the mail-box is incorrectly expressed

in the liver in PSC patients? Increased expression of MAdCAM-1 caused

by methylamine allows the T cells (mail) to be delivered to the wrong

address!

Because a certain type of T cells called Th17 cells are now being

implicated in inflammatory bowel disease, autoimmune hepatitis and

primary biliary cirrhosis (see the other abstracts posted earlier) it

will be interesting to see if such Th17 cells are being delivered

inappropriately to the liver in PSC?

The Th17 cells are very pro-inflammatory. Their production in the gut

can be inhibited by retinoic acid (vitamin A). There is also some

evidence that production of Th17 cells can be inhibited by

eicosapentaenoic acid (EPA); a component of fish oils. They can also

be suppressed by anti-inflammatory regulatory T cells (Tregs).

Several of the susceptibility genes involved in inflammatory bowel

disease seem to be involved in Th17 cell production and impairments

in Tregs.

Best regards,

Dave

(father of (23); PSC 07/03; UC 08/03)

Link to comment
Share on other sites

Hi Lori;

I'll do my best to try to explain this information, although it is

awfully complicated, and I might have to simplify things a lot. Here

goes ....

In the gut there are lymphoid tissues that produce immune cells whose

main job is to take care of various foreign organisms (e.g.

bacteria). The gut lymphoid tissue produces dendritic cells which

secrete various substances that activate and educate T cells. For

instance, the dendritic cells produce retinoic acid (from vitamin A)

that tells the T cells to produce molecules on their surfaces that

act as zip-codes, and which instruct the T cells where they should be

delivered in the body. CCR9 and a4ß7 are the zip-codes on the T

cells. The T cells then go roaming around the body until they find

their correct mail-box. They are usually delivered to cells that

express MADCAM-1 and CCL25, and these are usually found only in the

gut. In this way the T cells are delivered (like a piece of mail) to

the correct address, where they then can do their job of

orchestrating the neutralization or killing of invading organisms in

the gut.

In PSC, however, it seems that the mail box (MAdCAM-1 and CCL25) is

incorrectly expressed in the liver, so the T cells go to the liver

instead of to the gut, and cause inflammation in the liver. It

appears that only the dendritic cells in the gut do the " zip-code "

imprinting of the T cells. But it's still not clear to me whether

something else may be going awry with this " zip-code " imprinting

system or mail delivery system? A disgruntled postal worker?

The interesting new " lead " is that the dietary substance methylamine

is an inducer of MAdCAM-1 in the liver, suggesting that this dietary

substance may be a key to why the mail-box is incorrectly expressed

in the liver in PSC patients? Increased expression of MAdCAM-1 caused

by methylamine allows the T cells (mail) to be delivered to the wrong

address!

Because a certain type of T cells called Th17 cells are now being

implicated in inflammatory bowel disease, autoimmune hepatitis and

primary biliary cirrhosis (see the other abstracts posted earlier) it

will be interesting to see if such Th17 cells are being delivered

inappropriately to the liver in PSC?

The Th17 cells are very pro-inflammatory. Their production in the gut

can be inhibited by retinoic acid (vitamin A). There is also some

evidence that production of Th17 cells can be inhibited by

eicosapentaenoic acid (EPA); a component of fish oils. They can also

be suppressed by anti-inflammatory regulatory T cells (Tregs).

Several of the susceptibility genes involved in inflammatory bowel

disease seem to be involved in Th17 cell production and impairments

in Tregs.

Best regards,

Dave

(father of (23); PSC 07/03; UC 08/03)

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You said that methylamine is a dietary substance. Where is methylamine found in the diet and I wonder if they find a connection between the Th-17 cells to PSC, and also find more support for MAdCAM-1 if limiting this substance will help.Thank you for passing the research along.nnenne

Duluth, Minnesota

UC 2002, PSC 2008Subject: Re: New PSC leadsTo: Date: Friday, November 7, 2008, 5:15 AM

Hi Lori;

I'll do my best to try to explain this information, although it is

awfully complicated, and I might have to simplify things a lot. Here

goes ....

In the gut there are lymphoid tissues that produce immune cells whose

main job is to take care of various foreign organisms (e.g.

bacteria). The gut lymphoid tissue produces dendritic cells which

secrete various substances that activate and educate T cells. For

instance, the dendritic cells produce retinoic acid (from vitamin A)

that tells the T cells to produce molecules on their surfaces that

act as zip-codes, and which instruct the T cells where they should be

delivered in the body. CCR9 and a4ß7 are the zip-codes on the T

cells. The T cells then go roaming around the body until they find

their correct mail-box. They are usually delivered to cells that

express MADCAM-1 and CCL25, and these are usually found only in the

gut. In this way the T cells are delivered (like a piece of mail) to

the correct address, where they then can do their job of

orchestrating the neutralization or killing of invading organisms in

the gut.

In PSC, however, it seems that the mail box (MAdCAM-1 and CCL25) is

incorrectly expressed in the liver, so the T cells go to the liver

instead of to the gut, and cause inflammation in the liver. It

appears that only the dendritic cells in the gut do the "zip-code"

imprinting of the T cells. But it's still not clear to me whether

something else may be going awry with this "zip-code" imprinting

system or mail delivery system? A disgruntled postal worker?

The interesting new "lead" is that the dietary substance methylamine

is an inducer of MAdCAM-1 in the liver, suggesting that this dietary

substance may be a key to why the mail-box is incorrectly expressed

in the liver in PSC patients? Increased expression of MAdCAM-1 caused

by methylamine allows the T cells (mail) to be delivered to the wrong

address!

Because a certain type of T cells called Th17 cells are now being

implicated in inflammatory bowel disease, autoimmune hepatitis and

primary biliary cirrhosis (see the other abstracts posted earlier) it

will be interesting to see if such Th17 cells are being delivered

inappropriately to the liver in PSC?

The Th17 cells are very pro-inflammatory. Their production in the gut

can be inhibited by retinoic acid (vitamin A). There is also some

evidence that production of Th17 cells can be inhibited by

eicosapentaenoic acid (EPA); a component of fish oils. They can also

be suppressed by anti-inflammatory regulatory T cells (Tregs).

Several of the susceptibility genes involved in inflammatory bowel

disease seem to be involved in Th17 cell production and impairments

in Tregs.

Best regards,

Dave

(father of (23); PSC 07/03; UC 08/03)

Link to comment
Share on other sites

You said that methylamine is a dietary substance. Where is methylamine found in the diet and I wonder if they find a connection between the Th-17 cells to PSC, and also find more support for MAdCAM-1 if limiting this substance will help.Thank you for passing the research along.nnenne

Duluth, Minnesota

UC 2002, PSC 2008Subject: Re: New PSC leadsTo: Date: Friday, November 7, 2008, 5:15 AM

Hi Lori;

I'll do my best to try to explain this information, although it is

awfully complicated, and I might have to simplify things a lot. Here

goes ....

In the gut there are lymphoid tissues that produce immune cells whose

main job is to take care of various foreign organisms (e.g.

bacteria). The gut lymphoid tissue produces dendritic cells which

secrete various substances that activate and educate T cells. For

instance, the dendritic cells produce retinoic acid (from vitamin A)

that tells the T cells to produce molecules on their surfaces that

act as zip-codes, and which instruct the T cells where they should be

delivered in the body. CCR9 and a4ß7 are the zip-codes on the T

cells. The T cells then go roaming around the body until they find

their correct mail-box. They are usually delivered to cells that

express MADCAM-1 and CCL25, and these are usually found only in the

gut. In this way the T cells are delivered (like a piece of mail) to

the correct address, where they then can do their job of

orchestrating the neutralization or killing of invading organisms in

the gut.

In PSC, however, it seems that the mail box (MAdCAM-1 and CCL25) is

incorrectly expressed in the liver, so the T cells go to the liver

instead of to the gut, and cause inflammation in the liver. It

appears that only the dendritic cells in the gut do the "zip-code"

imprinting of the T cells. But it's still not clear to me whether

something else may be going awry with this "zip-code" imprinting

system or mail delivery system? A disgruntled postal worker?

The interesting new "lead" is that the dietary substance methylamine

is an inducer of MAdCAM-1 in the liver, suggesting that this dietary

substance may be a key to why the mail-box is incorrectly expressed

in the liver in PSC patients? Increased expression of MAdCAM-1 caused

by methylamine allows the T cells (mail) to be delivered to the wrong

address!

Because a certain type of T cells called Th17 cells are now being

implicated in inflammatory bowel disease, autoimmune hepatitis and

primary biliary cirrhosis (see the other abstracts posted earlier) it

will be interesting to see if such Th17 cells are being delivered

inappropriately to the liver in PSC?

The Th17 cells are very pro-inflammatory. Their production in the gut

can be inhibited by retinoic acid (vitamin A). There is also some

evidence that production of Th17 cells can be inhibited by

eicosapentaenoic acid (EPA); a component of fish oils. They can also

be suppressed by anti-inflammatory regulatory T cells (Tregs).

Several of the susceptibility genes involved in inflammatory bowel

disease seem to be involved in Th17 cell production and impairments

in Tregs.

Best regards,

Dave

(father of (23); PSC 07/03; UC 08/03)

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Thanks for that wonderful explanation Dave. In addition, I googled

" methylamine, " and found this free-use abstract regarding cigarette

smoking and methylamine. Another reason for PSCers not to smoke? But

then I'm confused, as I thought smokers were less likely to get PSC than

non-smokers? .

1) Neuropsychiatry Research Unit, Department of Psychiatry, University

of Saskatchewan, Saskatoon, Saskatchewan, Canada, S7N 5E4.

Abstract Methylamine is a constituent of cigarette smoke and the major

end product of nicotine metabolism. Smoking or nicotine can induce the

release of adrenaline, which is in turn deaminated by monoamine oxidase,

also producing methylamine. We found that the urinary level of

methylamine was significantly elevated following administration of

nicotine (25 mg/Kg, i.p.). Semicarbazide-sensitive amine oxidase (SSAO)

inhibitors further increased the excretion of methylamine induced by

nicotine. Following administration of L-(—)-[N-methyl-3H]nicotine

long-lasting irreversible radioactive adducts were detected in different

mouse tissues and such adduct formation could be blocked by selective

SSAO inhibitors. These adducts are probably cross-linked oligoprotein

complexes cross-linked by formaldehyde. The findings support the idea

that nicotine can enhance SSAO/methylamine-mediated increase of

formaldehyde and oxidative stress and this could in part contribute the

adverse effect of health associated with smoking.

http://www.springerlink.com/content/m72935j154766688/

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Hi nne;

Good question. I'm not sure whether the authors of the abstract were

suggesting that methylamine present in food might be responsible, or

whether it is bacteria in the colon that generate methylamine from

normal dietary constituents that are responsible. There are studies

showing that certain colonic bacteria can make a lot of different

amines, including methylamine. The methylamine produced by these

bacteria is made from a normal amino acid found in all protein,

glycine. This is described in detail in this paper:

Appl. Environ. Microbiol. 55: 2894-2898 (1989)

Influence of pH, nutrient availability, and growth rate on amine

production by Bacteroides fragilis and Clostridium perfringens.

C, Macfarlane GT

http://aem.asm.org/cgi/reprint/55/11/2894?view=long&pmid=2560361

I don't know whether they have tried feeding this substance to lab

animals to see whether it alters MAdCAM-1 expression in the liver as

it does in cell cultures. I'm sure that this will be on their list of

experiments to try next!

Best regards,

Dave

(father of (23); PSC 07/03; UC 08/03)

>

> You said that methylamine is a dietary substance. Where is

methylamine found in the diet and I wonder if they find a connection

between the Th-17 cells to PSC, and also find more support for MAdCAM-

1 if limiting this substance will help.

>

> Thank you for passing the research along.

>

> nne

>

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Share on other sites

Hi nne;

Good question. I'm not sure whether the authors of the abstract were

suggesting that methylamine present in food might be responsible, or

whether it is bacteria in the colon that generate methylamine from

normal dietary constituents that are responsible. There are studies

showing that certain colonic bacteria can make a lot of different

amines, including methylamine. The methylamine produced by these

bacteria is made from a normal amino acid found in all protein,

glycine. This is described in detail in this paper:

Appl. Environ. Microbiol. 55: 2894-2898 (1989)

Influence of pH, nutrient availability, and growth rate on amine

production by Bacteroides fragilis and Clostridium perfringens.

C, Macfarlane GT

http://aem.asm.org/cgi/reprint/55/11/2894?view=long&pmid=2560361

I don't know whether they have tried feeding this substance to lab

animals to see whether it alters MAdCAM-1 expression in the liver as

it does in cell cultures. I'm sure that this will be on their list of

experiments to try next!

Best regards,

Dave

(father of (23); PSC 07/03; UC 08/03)

>

> You said that methylamine is a dietary substance. Where is

methylamine found in the diet and I wonder if they find a connection

between the Th-17 cells to PSC, and also find more support for MAdCAM-

1 if limiting this substance will help.

>

> Thank you for passing the research along.

>

> nne

>

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Share on other sites

Hi ;

That's interesting. However, I don't think the amount of methylamine

that one would get by smoking would be as much as that obtained from

bacteria in the colon, but I'm certainly not an expert on this!

With regard to the PSC - smoking issue, this abstract appears in the

AASLD 2008 Liver Meeting Abstracts, and includes your favorite doc,

Dr. Karlsen, as co-author:

Final ID: 670

Smoking may delay disease onset and disease progression in primary

sclerosing cholangitis

J. R. Hov; 1; K. K. nsen; 1; T. H. Karlsen; 1; E. Schrumpf; 1;

K. M. Boberg; 1;

1. Department of Medicine, Rikshospitalet University Hospital and

University of Oslo, Oslo, Norway.

Abstract Body: Introduction. Primary sclerosing cholangitis (PSC) is

a chronic inflammatory disease of the biliary tree leading to liver

cirrhosis and often requiring liver transplantation. The etiology is

unknown, but epidemiological studies point to the presence of both

genetic (strong associations in the HLA complex on chromosome 6p21)

and environmental (protective effect of smoking) risk factors. Little

is known on the possible relationship between these risk factors and

to what extent smoking may influence disease course in PSC.

Material and methods. 147 consecutive PSC patients (74% male) in the

Medical Department of Rikshospitalet University Hospital were

recruited over a 2 year period. PSC diagnosis was based on accepted

criteria and typical findings on cholangiography. All patients were

interviewed by the same gastroenterologist regarding smoking history

including age of onset and duration. HLA genotyping was performed

using DNA sequencing based technology. Statistical analysis was

performed in SPSS 15.0.

Results. At diagnosis of PSC only 7% (10/147) were current smokers.

24% (35/147) were ever smokers (previous or current smokers) and 76%

(112/147) were never smokers. Median age at diagnosis was 32 years

(range 13-77) for never smokers compared with 41 years (range 19-65)

for ever smokers (p<0.001, Mann-Whitney U test). 42% (16/38)

of the female patients were ever smokers compared with 17% (19/109)

of the male (p=0.002, chi-square test). Median follow-up from

diagnosis was 5 years (range 0-28). Liver transplantation or death

occurred in 55% (81/147). In an age and gender-adjusted

regression model ever smoking was independently associated with

prolonged time from diagnosis to death or liver transplantation (odds

ratio 0.51; 95% confidence interval 0.29-0.89, p=0.019). We found no

significant differences in smoking prevalence between patients of

different HLA types in the present dataset.

Conclusion. In this PSC cohort from a tertiary referral centre, a

history of smoking was associated with higher age at diagnosis and

slower disease progression. It is noteworthy that the proportion of

female patients with a history of smoking was significantly higher

than among male patients. We did not detect any significant

differences in smoking prevalence between patients of different HLA

types.

Best regards,

Dave R.

>

> Thanks for that wonderful explanation Dave. In addition, I googled

> " methylamine, " and found this free-use abstract regarding cigarette

> smoking and methylamine. Another reason for PSCers not to smoke?

But

> then I'm confused, as I thought smokers were less likely to get PSC

than

> non-smokers? .

Link to comment
Share on other sites

Hi ;

That's interesting. However, I don't think the amount of methylamine

that one would get by smoking would be as much as that obtained from

bacteria in the colon, but I'm certainly not an expert on this!

With regard to the PSC - smoking issue, this abstract appears in the

AASLD 2008 Liver Meeting Abstracts, and includes your favorite doc,

Dr. Karlsen, as co-author:

Final ID: 670

Smoking may delay disease onset and disease progression in primary

sclerosing cholangitis

J. R. Hov; 1; K. K. nsen; 1; T. H. Karlsen; 1; E. Schrumpf; 1;

K. M. Boberg; 1;

1. Department of Medicine, Rikshospitalet University Hospital and

University of Oslo, Oslo, Norway.

Abstract Body: Introduction. Primary sclerosing cholangitis (PSC) is

a chronic inflammatory disease of the biliary tree leading to liver

cirrhosis and often requiring liver transplantation. The etiology is

unknown, but epidemiological studies point to the presence of both

genetic (strong associations in the HLA complex on chromosome 6p21)

and environmental (protective effect of smoking) risk factors. Little

is known on the possible relationship between these risk factors and

to what extent smoking may influence disease course in PSC.

Material and methods. 147 consecutive PSC patients (74% male) in the

Medical Department of Rikshospitalet University Hospital were

recruited over a 2 year period. PSC diagnosis was based on accepted

criteria and typical findings on cholangiography. All patients were

interviewed by the same gastroenterologist regarding smoking history

including age of onset and duration. HLA genotyping was performed

using DNA sequencing based technology. Statistical analysis was

performed in SPSS 15.0.

Results. At diagnosis of PSC only 7% (10/147) were current smokers.

24% (35/147) were ever smokers (previous or current smokers) and 76%

(112/147) were never smokers. Median age at diagnosis was 32 years

(range 13-77) for never smokers compared with 41 years (range 19-65)

for ever smokers (p<0.001, Mann-Whitney U test). 42% (16/38)

of the female patients were ever smokers compared with 17% (19/109)

of the male (p=0.002, chi-square test). Median follow-up from

diagnosis was 5 years (range 0-28). Liver transplantation or death

occurred in 55% (81/147). In an age and gender-adjusted

regression model ever smoking was independently associated with

prolonged time from diagnosis to death or liver transplantation (odds

ratio 0.51; 95% confidence interval 0.29-0.89, p=0.019). We found no

significant differences in smoking prevalence between patients of

different HLA types in the present dataset.

Conclusion. In this PSC cohort from a tertiary referral centre, a

history of smoking was associated with higher age at diagnosis and

slower disease progression. It is noteworthy that the proportion of

female patients with a history of smoking was significantly higher

than among male patients. We did not detect any significant

differences in smoking prevalence between patients of different HLA

types.

Best regards,

Dave R.

>

> Thanks for that wonderful explanation Dave. In addition, I googled

> " methylamine, " and found this free-use abstract regarding cigarette

> smoking and methylamine. Another reason for PSCers not to smoke?

But

> then I'm confused, as I thought smokers were less likely to get PSC

than

> non-smokers? .

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Share on other sites

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