49 replies to this topic

[Michael]

Thanks to Elus for providing the paper. This is a very interesting report, tho' it's too early to say how promising it is. "The total areas (in µm2 ) occupied by lipofuscin per 1000 µm2 sectioned RPE cytoplasm clearly decreased in the 3 groups of Remofuscin-treated animals … Concerning the melanin granules in the RPE cytoplasm, no statistical significance was seen". Happily, they do report that "No immunoreactivity for the proliferation marker Ki-67 could be found .. ruling out the possibility that cellular pigment was “diluted” by cell division" (as with centrophenoxine); OTOH, they're saying it's been removed in the sense of having been exported , not in the sense of being degraded or detoxified.

That's still probably a good thing, but for most animals there was no improvement in RPE structure: They show a picture of very extensive clearance of lipofuscin and improved RPE morphology from one animal from the highest-dose group (Group 4), but "In the 17 remaining eyes from groups 2–4 ... the gross morphology of the RPE cells stayed unaltered ... Moreover, the height of the RPE cell layer was the same as in untreated animals indicating that death of RPE cells did not occur." If only one animal out of 17, at the highest dose, got any morphological benefits, this may not work for many patients, esp as we have no good idea about what a safe dose will actually turn out to be, so this dose may not actually prove feasible. And, importantly, they don't offer any evidence of improved function , either of the RPE itself or of visual function, which latter they didn't evaluate at all.


Also, even if RPE export is good in the short term for the health of the RPE cells themselves and even AMD per se, I'd want to know what happpens to the exported lipofuscin: "Occasionally and only after high-dose treatment with Remofuscin (group 4), lipofuscin granules were present in heavily pigmented cells between the Bruch’s membrane [the basement membrane of the RPE] and the RPE cell layer (Fig. 2b and e )." And, "Fusion of melanosomes and lipofuscin granules was observed in the RPE (not shown)." It'd be great if it was ultimately eg. shuttled off to erythrocytes and be transported to the liver for excretion (as was hypothesized, somewhat out of the air, by PMID 15585347, cited above by steampoweredgod), but (again) most of it remained in the RPE cell layer, and only a quarter of the highest-dose animals did it even reach Bruch's membrane. RPE lipofuscin building up there could just be creating a new problem, like toxic waste exports to the developing world.

The finding, mentioned in the abstract, that "In 4 eyes, macrophages were detected which had taken up lipofuscin" is certainly promising, in that it might offer a mechanism whereby the stuff might indeed be degraded rather than just exocytosed with possibly deleterious effects, but (a) they don't really show what happens to it once engulfed, and (b)they only appeared in a minority of animals in the highest dose group: "These macrophages were filled with lipofuscin granules, melanosomes, and melanolipofuscin granules and were therefore highly pigmented (Fig. 3 a). Pigment granules of heterogenous morphology within these macrophages appeared to disintegrate into smaller units [That would be promising, I don't see how the heck they determined that, tho' I freely admit that inspection of micrographs, etc is a weak spot for me -MR]. Pigment-laden macrophages were also seen within the choroid (Fig. 3 c), and extensions of cells of unknown origin (probably macrophages) were also detected within the Bruch’s membrane (not shown). The depigmentation induced by Remofuscin is RPE-specific because the choroidal melanocytes were not affected by the treatment."

We also don't know what exactly they were clearing out, except in the small minority of high-dose eyes where export seems to have been complete. "Because of several chemically similar bisretinoid compounds of lipofuscin fluoresce in the same region, the microscopical method was not specific enough to identify specific fluorophores of lipofuscin that could be selectively targeted by Remofuscin."

Finally, there's the immediate, pharmacological mechanism: "Remofuscin [is] a potent and reversible inhibitor of the H+/K+ ATPase" -- the proton pump of the stomach. Ie, it's a proton-pump inhibitor, like omeprazole (Prilosec) and Nexium, thus explaining the fact that these monkeys were in a study whose primary purpose was to study ulcers. Well, have a look at the PPI side effects:
http://en.wikipedia....Adverse_effects

As noted, many of the favorable effects happened only in a minority within the highest-dose group (in one case only one animal); we have no good idea about safety yet, & thus dose-limiting toxicity could mean these doses are out of the question (tho' they don't say their monkeys were a mess of diarrhea, pneumonia, nephritis or C. difficile). Messing with metabolic pathways is, of course, not the approach I'd favor IAC.

Edited by Michael, 08 May 2012 - 11:50 AM.

[eighthman]

There are reports that astaxanthin may remove "age spots". This is asserted by Dr. Perricone and anecdotally. It does seem to prevent them and extends life span in C. elegans.

Needs more research.

[albedo]

I was reading about centrophenoxine as slowing the accumulation of lipofuscin.

[Michael]

There are reports that astaxanthin may remove "age spots". This is asserted by Dr. Perricone and anecdotally. It does seem to prevent them and extends life span in C. elegans.

"Age spots"/"liver spots," despite despite Pearson & Shaws' claims, are not lipofuscin. Perricone is a flake. And all kinds of stuff extends LS in C. elegans that doesn't work in mammals; ignore it.

I really can be pleasant company in person .

I was reading about centrophenoxine as slowing the accumulation of lipofuscin.

Very likely bunk, as noted here. Ulf Brunk thinks that, if it happens at all, it's the result of cell division.

[DukeNukem]

Michael, do you know what causes age spots?

[Michael]

Michael, do you know what causes age spots?

Melanin clumping, according to the Mayo Clinic; excess melanocyte activity, according to these lecture notes (PowerPoint). See also this from MSN Health.

[Michael]

Followup: I got some very useful feedback on this paper from Gouri Yogalingam, a lysosomal storage disease researcher that SENS Foundation was fortunate enough to snap up for the intramural Research Center:

1. I would like to know the mechanism by which the drug is triggering lysosomal exocytosis and if it is only occurring in RPE cells? Excessive lysosomal exocytosis is not a good thing in many instances. ... [For example], A deficiency of lysosomal sialidase (Neu1) leads to increased levels of LAMP-1-mediated lysosomal exocytosis by neutrophils in the bone marrow cavity. [MR: This is because lack of Neu1 means that it's not available to strip sialic acids from LAMP-1, and oversialylated LAMP-1 leads to loss of its inhibitory function over lyso exocytosis, apparently leading to a nonspecific puking out of its contents into the ECF]. The exocytosed lysosomal proteases cleave VCAM-1 present on stromal cells. VCAM-1 binds to VLA-4 on bone marrow progenitor cells. This VCAM-1 - VLA-4 interaction between bone marrow stromal cells and bone marrow progenitor cells helps to retain the progenitor cells in the bone niche. In Neu1-deficient mice the excessive lysosomal exocytosis results in cleavage of VCAM-1, loss of bone marrow progenitor cells from the bone niche and the onset of spleenic hematopoiesis. This is my postdoctoral work from St Jude Children's Hopsital in Sandra d'Azzo's lab and is an exampe of excessive lysosomal exocytosis being pathological. If you open up these mice their spleens are huge, due to the splenic hematopoiesis. I am sure that it can't be good for acidic lysosomes to be exocytosed in many other situations either. Many of the lysosomal proteases are active at neutral pH and this would mean that they could potentially cleave cell surface receptors and cell adhesion molecules.

[MR: The authors of the Remofuscin study apparently show exocytosis of aggregate, but that doesn't prove that the exocytosis is selective! And w/o even knowing the mechanism, it's hard to speculate one way or t'other.]

2. What affect does remofusin have on lysosomal pH in RPE and non-RPE cells and can this affect the normal turn-over of lysosomally-targeted proteins and organelles? This could be initially tested by labeling RPE cells that have been treated with remofusin with a pH sensor dye (lysotracker).

3. There was no quantitative biochemical data. EM images can be difficult to interpret. That's what I keep getting told about the images that I'm trying to publish at the moment. To truly conclude that Remofuscin is inducing exocytosis of lipofuscin the authors could have tested the drug in RPE cells pre-loaded with A2E. Aubrey and I were thinking at one point to ask the authors if they would like us to test this. We have the RPE cell model up and running, we know how to monitor A2E clearance in these cells by immunoflourescence and by HPLC and we also know how to monitor lysosomal exocytosis biochemically. It's something to think about if we get more resources. But I'm not sure about pursuing this approach because in the end it isn't really solving the problem of directly eliminating lipofuscin.

Edited by Michael, 26 May 2012 - 06:03 PM.

[xEva]

Look what I found:

http://en.wikipedia...._Lipofuscinoses

Cystagon (cysteamine)

In 2001 it was reported a drug used to treat cystinosis... may be useful in treating the infantile form of NCL. Preliminary results report the drug has completely cleared away storage material from the white blood cells of the first six patients, as well as slowing down the rapid neurodegeneration of infantile NCL.

Neuronal Ceroid Lipofuscinoses (NCL) is the general name for a family of at least eight genetically separate neurodegenerative disorders that result from excessive accumulation of lipopigments (lipofuscin) in the body's tissues.

The molecule seems very simple. -?

[Michael]

Look what I found:

http://en.wikipedia...._Lipofuscinoses

Cystagon (cysteamine)

In 2001 it was reported a drug used to treat cystinosis... may be useful in treating the infantile form of NCL. Preliminary results report the drug has completely cleared away storage material from the white blood cells of the first six patients, as well as slowing down the rapid neurodegeneration of infantile NCL.

Neuronal Ceroid Lipofuscinoses (NCL) is the general name for a family of at least eight genetically separate neurodegenerative disorders that result from excessive accumulation of lipopigments (lipofuscin) in the body's tissues.

The molecule seems very simple. -?

Yes, but irrelevant to "normal" aging, unfortunately. This is one f many examples of the overuse of 'lipofuscin' to mean "any kind of lysosomal [or sometimes even extralysosomal] aggregate material'. NCL (specifically, Batten disease) patients lack the CLN1 (infantile Batten disease) gene, and so fail to remove fatty acids from a variety of proteins, where the fatty acid is covalently linked to cysteine residues; as a result, their cells & lyso accumulate with such peptides and their secondary, aggregated products, and many of them will be severely cognitively impaired and blind in infancy, and dead by age 10. Cysteamine, if it works (trials are still ongoing), would do so because it lowers cell cysteine levels, thereby reducing the formation of such proteins and giving the cell a better chance of clearing the stuff out secondarily. This has nothing to do with what happens in the rest of us as we age, except by analogy.

Similarly, there are good treatments for many other lysosomal storage diseases (mostly, replacing the missing enzyme, but in other cases (like this one), by substrate reduction), but shooting normally-aging people up with these enzymes isn't helpful. We need new enzymes to go after the junk that evolution has not given us enzymes to degrade.

On all of this, see Ending Aging, chapter 7.

[xEva]

Well, since these lipofuscin threads came up in C60oo forum, I re-read them just now. The impression I get is that Michael believes that only SENS has the right definition of lipofuscin and only they have a viable strategy to find a way to remove it, while everybody else is just ..well, lacking. What bothers me the most is that the nature's ability to do that adequately is denied (here).
 
Now that years pass and evidence accumulates, it looks more and more like SENS have been barking up the wrong trees. The focus on specific molecular pathways in their "engineering solutions" obscures the lack of understanding of how living things operate as whole systems.

Funny that in the other lipofuscin thread, Michael argues with the same vigor against detrimental effects of extra iron. And the other of their most prominent misses, imo, were fasting and telomere attrition. What they do best, I think, is bringing the awareness of the problem of aging to the public. They should concentrate on that and leave the science to those with a better sense for biology.

[niner]

Well, since these lipofuscin threads came up in C60oo forum, I re-read them just now. The impression I get is that Michael believes that only SENS has the right definition of lipofuscin and only they have a viable strategy to find a way to remove it, while everybody else is just ..well, lacking. What bothers me the most is that the nature's ability to do that adequately is denied (here).
 
Now that years pass and evidence accumulates, it looks more and more like SENS have been barking up the wrong trees. The focus on specific molecular pathways in their "engineering solutions" obscures the lack of understanding of how living things operate as whole systems.

 

If nature is able to clear lipofuscin, then why is lipofuscin a problem?  What's the evidence that the SENS guys are wrong?

[Kevnzworld]

" Grape seed flavanols, but not Port wine, prevent ethanol-induced neuronal lipofuscin formation."
http://www.ncbi.nlm....1755517/related

I have been considering adding piracetam to my regimen for many reasons, this might be the deciding factor
" Piracetam was found to markedly decrease the formation of neuronal lipofuscin"
http://www.ncbi.nlm....tam, lipofuscin

I'm also considering DMAE.. Starting with smaller dosages to determine tolerability .
" Administration in the drinking water of 10 mM dimethylaminoethanol to the C3H/HeN mice or 15 mM to the C3H/HeJ(+) mice did not result in significant differences between treated and untreated groups in average survival. No changes in age-related organ structure or morphology were observed with dimethylaminoethanol treatment, except for an apparent decrease in the amount of lipofuscin in the liver judged in histological sections"
http://www.sciencedi...047637488900681

Lastly, I began supplementing with creatine, ( 2500 mg ) to prevent age related muscle loss. It seems that it also has this added benefit
" The median healthy life span of Cr-fed mice was 9% higher than in control mice, and they performed significantly better in neurobehavioral tests. In brains of Cr-treated mice, there was a trend towards a reduction of reactive oxygen species and significantly lower accumulation of the aging pigment lipofuscin."
http://www.neurobiol...0111-X/abstract

Edited by Kevnzworld, 20 July 2014 - 05:09 PM.

[niner]

It's possible to slow the formation of lipofuscin.  Slowing the development of ROS, or otherwise reducing the effects of them, will result in less oxidized material to be removed, for example.  Actually removing existing lipofuscin is a lot harder, though perhaps not impossible.

[Aardvark202]

Hey everyone,

 

My group is also working on A2E lipofuscin in the retina, and we've managed to remove it with a different treatment (using cyclodextrins).  We published this paper in PNAS earlier this year if anyone's interested:

 

http://www.pnas.org/...nt/111/14/E1402

 

My dissertation project is to work on optimizing and improving the removal process.  If anyone has any questions or input, please feel free!

 

-Kris

[niner]

Hi Kris, thanks for checking in.   Are lipofuscin bisretinoids found in other places besides RPE?   What's your estimate of the probability that LBs are causal in AMD?

[xEva]

Hi Kris, that's very interesting. I also read the wiki page on cyclodextrins  (they are so  pretty )  I see they are also used in food industry. I wonder if there is a way to deliver them other than injection or IV. Though the wiki article says:

α-Cyclodextrin has been authorized for use as a dietary fiber in the European Union since 2008.[6] In 2013 the EU commission has verified a health claim for alpha-cyclodextrin. The EU assessment report confirms that consumption of alpha-cyclodextrin can reduce blood sugar peaks following a high-starch meal.[7]

Would eating them do anything for lipofuscin?

thanks

Edited by xEva, 13 December 2014 - 06:52 AM.

[Michael]

Hi Kris, that's very interesting. I also read the wiki page on cyclodextrins  (they are so  pretty )  I see they are also used in food industry. I wonder if there is a way to deliver them other than injection or IV. Though the wiki article says:
 

α-Cyclodextrin has been authorized for use as a dietary fiber in the European Union since 2008.[6] In 2013 the EU commission has verified a health claim for alpha-cyclodextrin. The EU assessment report confirms that consumption of alpha-cyclodextrin can reduce blood sugar peaks following a high-starch meal.[7]

Would eating them do anything for lipofuscin?

 

Nope. The reason alpha-cyclodextrins lower postprandial glucose and cholesterol, and the reason they got relatively easy approval for use as food additives even in the EU, is because they aren't absorbed systemically: they work largely as soluble fiber does, binding excreted bile acids and slowing absorption of glucose.

Edited by Michael, 13 December 2014 - 06:46 PM.

[Aardvark202]

Hey Niner, LB's are found in significant levels exclusively in the RPE.  They are an accidental oxidative byproduct of the visual cycle, which occurs when retinoids in the photoreceptors involved in visual transduction are altered by light and recycled to the cells that do the dirty work of catabolism, the RPE.

 

Significant amounts of evidence show that LB's cause cell death in vitro, and they induce lysosomal dysfunction in the same manner as other forms of lipofuscin.  In addition, a genetic disease known as Stargardt's disease results primarily in massive LB accumulation in the RPE and secondarily by macular degeneration in the 30s.  There is a debate about whether All Trans Retinal or A2E are more toxic in vivo, but it's safe to say that removing them would help.  It's also likely IMO that the RPE becomes more susceptible to damage from LB's with age, rather than just becoming damaged by accumulating more.

 

EvaX, I would definitely say that it would be ideal to use cyclodextrins intravenously (directly into the back of the eye would be most ideal for this purpose, but not essential). If given elsewhere in the body many will be filtered out in the kidney.  High concentrations in the eye will be necessary to remove lipofuscin.

[ClarkSims]

Previously someone asked where to buy remofuscin. I found this after much research. I am not sure I am correct.  Sigma has some contradictory information on it's site for a different chemical, that goes by one of remofuscin's many aliases,  These are the aliases:

    (7R,8R,9R)-7-(2-methoxyethoxy)-2,3-dimethyl-9-phenyl-7,8,9,10-tetrahydroimidazo(1,2-H)(1,7)naphtyridin-8-ol
    2,3-dimethyl-8-hydroxy-7-(2-methoxyethoxy)-9-phenyl-7,8,9,10-tetrahydroimidazo(1,2-h)(1,7)naphthyridine
    BYK 61359
    BYK-61359
    BYK61359
    remofuscin
    soraprazan
    CAS No. 261944-46-1
 

Here are sellers

http://www.chemicalr...s/pid382013.htm

https://pubchem.ncbi...hemical-Vendors

 

Here is the confusing information from Sigma. I think they have the article, "Soraprazan: setting new standards in inhibition of gastric acid secretion.", referenced to the wrong drug.

http://www.sigmaaldr...ng=en&region=US

 

If anyone has any input on why Sigma would call C₁₇H₁₅N₃O,  aka CAS 76081-98-6 , by the name Soraprazan,   please add the answer to the thread.

 

The chemical Sigma calls, Soraprazan, is a different chemical, than what the other sites call Soraprazan.

 

Edited by ClarkSims, 27 January 2016 - 02:50 AM.

[GABAergic]

there is no update on here for the past 3 years. anyone still interested in this, wishes to contribute a bit more. im interested on how this whole lipofuscin removal is going currently