Free mitochondria in our blood

[sangui]

I found an article about free mitochondria in the blood, and it's puzzle me.

The link of the article : https://faseb.onlinelibrary.wiley.com/doi/epdf/10.1096/fj.201901917RR

I found the article rather good with a good explanation of the MATERIALS AND METHODS (even if I don't understand everything).

But I have some lack of understanding :

                   - Does it the first time than we found free mitochondria in animal organism ?

                   - Why do we need the ability to produce ATP outside of the cells ?

                   - It may be a processus to modulate the immune system (I read than mitochondria can act like DAMPs), but how do we avoid a reaction of inflammation a basal level ?

 

Thanks for reading

[Endy0816]

Reading that it was previously found that platelets release them to promote inflammation. They are descendants of bacteria, so pretty logical that they can still trigger an immune response.

https://ashpublications.org/blood/article/124/14/2173/33091/Platelets-release-mitochondria-serving-as

[sangui]

Yes, but they show than we have free mitochondria are present even in physiological state.

So it must be usefull in another way, no ?

[Endy0816]

8 hours ago, sangui said:

Yes, but they show than we have free mitochondria are present even in physiological state.

So it must be usefull in another way, no ?

Possibly.

I know if I had my choice I'd use them to help repair/replace other mitochondria that have suffered damage, but I don't know if such a mechanism actually exists. We do know their distant ancestors entered the ancestral cell at some point however.

Edited April 16, 2020 by Endy0816

[StringJunky]

31 minutes ago, Endy0816 said:

Possibly.

I know if I had my choice I'd use them to help repair/replace other mitochondria that have suffered damage, but I don't know if such a mechanism actually exists. We do know their distant ancestors entered the ancestral cell at some point however.

That's a working hypothesis:

Quote

Thierry says he thinks it’s more likely that mitochondria are being actively released by certain cells in their functional state, and that the organelles perhaps play a signaling role. One idea, for instance, is that cells could release mitochondria, which are then taken up by other cells that are damaged and are in need of them, he explains.

Picard agrees this is a possibility. In fact, some experiments have found that stem cells can release mitochondria in order to rescue damaged cells, and mitochondria have been shown to translocate from one neighboring cell to another. Perhaps parts of the body produce mitochondria and release them into the bloodstream so that compromised tissues can use them, in a similar way as glucose is stored within cells but also circulates in the bloodstream. “In biology there’s rarely things that happen for no reason. I think that it’s quite likely that the circulating mitochondria have a functional role to play,” although more research is needed to find out, Picard says.

https://www.the-scientist.com/news-opinion/researchers-find-cell-free-mitochondria-floating-in-human-blood--67071

 

[Endy0816]

1 hour ago, StringJunky said:

That's a working hypothesis:

 

lol, nice to see not too far off from what the real researchers are thinking.

Obviously phagocytes exist so perhaps other cells can use the same method to engulf them when needed. Possibly they have some means to 'infect' a cell themselves too.

Edited April 17, 2020 by Endy0816

[sangui]

6 hours ago, StringJunky said:

That's a working hypothesis:

 

Thanks for your reply ^^. Your link answer my questions.