Question: Academic question.
In a net doctor's remarks on oxidative stress, I read that it can affect DNA, proteins and membranes. He did not make clear what he meant made it sound like it was possible that DNA could be damaged.but didn't say how. I am only interested in processes that take place due to oxidation within the cell, that is aside from exogenous sources such as radiation, which is indiscriminate damage. Considering only the oxidation process in the cell,which take place in mitochondria, is there any case to be made for free radicals/ oxidative stress to damage DNA? In the mitochondria DNA? In the nucleus DNA?

Thank you for your answer.

Yes the sort you have stated are all from outside the cell. I can appreciate that some sources can affect what is going on in the cytoplasm and nucleus, such as radiation.

The ones I am wondering about are sources inside the cell. I have read about supposed imbalances of oxidative processes causing oxidative stress. I find this hard to accept that what goes on in the mitochondria or even in the cytoplasm as some processes, such as modulating messengers that regulate cell membrane functions and many and varied cellular responses, can supposed be out of balance and affect the DNA in the nucleus. Can you say something about what they are calling imbalances in reactive oxygen species produced in normal process and can that imbalance, if there is really imbalance, affect DNA?

Thank you for your information about oxidative stress. I would like to ask you again, specifically this time.

There is a guy on a Diabetes forum that says he has numbness in his feet and that it is due to diabetes and excess oxidative stress. I disagree with him. I believe that he must be upholding beliefs that cause his immune system to react unnecessarily and that this is the cause of the damage.

From my knowledge, I know that nerve cells, red blood cells (I am not sure about the small blood vessels) all have the "doors open" for glucose to enter. They don't need insulin. So they don't "change the locks on the doors" (insulin resistance) to prevent an excess of glucose going into the cells. From what I can see the glucose is not taken into the cell simply because it is available. It appears that they have structures on their cell membranes that hold the glucose. So they take in the amount that they need in accordance to their needs..So how can there be excess glucose enough to cause oxidative stress?

Also it appears that some research on excess oxidative stress is centered around genes associated with various aspects of oxidation processes but these genes are involved with immune system defence processes. For me this is more evidence that the oxidation in excess is deliberate but associated with an inappropriate immune system response (owing to false beliefs). That is evident in the many neurological and autoimmune diseases that are listed in association with oxidative stress. So his numb feet or nerve damage can't be caused by an excess of oxidative stress but an inappropriate immune system response, which of course involves high levels of oxidative stress but deliberate and not as an excess.
Thanks for your help.