Re: High cholesterol protective against infection?

On Thu, 03 Aug 2006 17:21:08 +0300, Matti Narkia <mna@xxxxxxxx> wrote:

HDL has antiviral, antiinflammatory and antioxidant activities, see

Singh IP, Baron S.
Innate defences against viraemia.
Rev Med Virol. 2000 Nov-Dec;10(6):395-403. Review.
PMID: 11114078 [PubMed - indexed for MEDLINE]
<http://www3.interscience.wiley.com/cgi-bin/fulltext/75504890/PDFSTART>

[snip]

Barter PJ, Nicholls S, Rye KA, Anantharamaiah GM, Navab M, Fogelman
AM.
Antiinflammatory properties of HDL.
Circ Res. 2004 Oct 15;95(8):764-72. Review.
PMID: 15486323 [PubMed - indexed for MEDLINE]
<http://circres.ahajournals.org/cgi/content/full/95/8/764>

[snip]

Navab M, Ananthramaiah GM, Reddy ST, Van Lenten BJ, Ansell BJ, Fonarow
GC, Vahabzadeh K, Hama S, Hough G, Kamranpour N, Berliner JA, Lusis
AJ, Fogelman AM.
The oxidation hypothesis of atherogenesis: the role of oxidized
phospholipids and HDL.
J Lipid Res. 2004 Jun;45(6):993-1007. Epub 2004 Apr 1. Review.
PMID: 15060092 [PubMed - indexed for MEDLINE]
<http://www.jlr.org/cgi/content/full/45/6/993>

But see also

Navab M, Anantharamaiah GM, Fogelman AM.
The role of high-density lipoprotein in inflammation.
Trends Cardiovasc Med. 2005 May;15(4):158-61. Review.
PMID: 16099381 [PubMed - indexed for MEDLINE]
<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=16099381>

"High-density lipoprotein (HDL) appears to have evolved as part
of the innate immune system, which in part uses an enhanced
oxidative state as a nonspecific means of protecting against
many pathogens. In the absence of acute or chronic
inflammation, HDL is anti-inflammatory in mice, rabbits, and
humans. However, with the onset of a systemic inflammatory
state such as what occurs in atherosclerosis, HDL becomes pro-
inflammatory, enhancing the inflammatory response. The major
apolipoprotein of HDL is apoA-I, which may be altered by
oxidative processes in patients with atherosclerosis. As a
result, HDL from such patients is less efficient in promoting
cellular cholesterol efflux. The ability of HDL to inhibit the
inflammatory properties of oxidized phospholipids and low-
density lipoproteins is also significantly altered. In mice and
monkeys, the administration of an apoA-I-mimetic peptide
renders pro-inflammatory HDL anti-inflammatory, improves HDL-
mediated cellular cholesterol efflux; in mice, it dramatically
inhibits atherosclerosis. Understanding the role of HDL in
inflammation may lead to new diagnostic and therapeutic
approaches to atherosclerosis and other inflammatory
conditions."


--
Matti Narkia
.