What Is The Turnover Rate Of The Cellular Components?

Posted on Mon, 22 Jun 2015

Question: Dear Doctor,

I would like to know about cellular components' turnover rate? Of course DNA is an axception but does EVERYTHING ELSE in a cell degrade and turn over?

Thanks and Regards,
XXXX

Answered by Dr. Diptanshu Das (23 minutes later)

Brief Answer:
The DNA of a cell gets digested along with rest of the cell during turnover

Detailed Answer:
Thanks for asking on HealthcareMagic.

Under normal scenario, a cell dies of a process called apoptosis or programmed cell death. After the purpose of the cell is served, at the end of its life cycle or after being tagged for deletion, the cell undergoes a programmed lysis. The surrounding structures are not affected and only the cell INCLUDING its DNA is broken down into fragments and the fragments get digested in small sacs containing digestive juices. The rate of cell break down varies from tissue to tissue. Somewhere it is rapid regeneration or break down in matter of minutes, whereas there are other cells that last life long.

I hope you get an idea. Let me know if you have any other queries.

Regards

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Diptanshu Das (1 hour later)

Thank you Dr. XXXXXXX ,

In lifelong cells, are the organelles and contents also lifelong? or are they under constant degradation and turnover? thanks

Answered by Dr. Diptanshu Das (3 hours later)

Brief Answer:
There is constant turnover of the organelles

Detailed Answer:
Thanks for asking back.

In permanent cells like the nerve cells that persist for a lifetime, the organelles are constantly renewed. On one hand new organelles are constantly produced. On the other hand the Golgi bodies give rise to small enzyme filled vacuoles called lysosomes which contains digestive enzymes. The redundant organelles are taken inside the lysosomes and are degraded. Both the production and destruction are continually going on.

Regards

Above answer was peer-reviewed by : Dr. Vinay Bhardwaj

Follow up: Dr. Diptanshu Das (15 hours later)

Thanks Dr XXXXXXX

I have another seperate question regarding growth and growth of cartilage.

Of course our bones renew themselves every few years - in children even faster renewal.

But does this renewal extend to cartilage portion of the bone? Or is it only actual bone that gets renewed?

Thanks and Best Regards

Answered by Dr. Diptanshu Das (20 hours later)

Brief Answer:
Cartilage renews itself but at a slow rate

Detailed Answer:
Thanks for writing back. Sorry for not being able to respond back earlier.

Not only bones, all cells including cartilage cells renew themselves. The following is an application of the same:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC0000/

Regards

Above answer was peer-reviewed by : Dr. Prasad

Follow up: Dr. Diptanshu Das (24 hours later)

Thanks Dr. XXXXXXX

The problem i have is the steroids i had was taken during growth phase in my life - 14 years old. I'm concerned that some long life tissue in my body such as cartilage was helped formed by these steroids. I would rather it was helped formed by something else.

So is cartilage formed by steroids i took still around today?

Answered by Dr. Diptanshu Das (1 hour later)

Brief Answer:
Even cartilagenous cells get renewed

Detailed Answer:
Thanks for writing back.

I do not think that you have anything to worry about. Our body is dynamic and constantly undergoing change. Old cells are being constantly renewed and so the chances are that even your cartilage cells have been entirely replaced by newer ones. I do not think that it is something to worry about.

Regards

Note: For detailed guidance on genetic screening consult a genetics specialist

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar