I have never studied biology but the following question seems meaningful to me. Suppose I take a cell, not that of a unicellular organism, but a human cell. Normally, there are some intracellular processes going on. If I understand correctly, one way a cell is going to die is that enough mistakes happen during these processes and it can't take it anymore.
Suppose I really need this cell alive and well in two hundred years and I do not really care what happens in the meanwhile. Is there a way to stop all the intracellular processes (protein synthesis, intracellular digestion, etc.), in a reversible fashion, so that I (or probably not me but a great-great-great-great-great-great-great-grandchild) could "start" this cell again after two hundred years pass? Now, two hundred years seem like too much for an experiment, but you get the idea; say, a month would be OK too.
Surely, some biologist thought about this at some point. Any references studying this question would be great.
EDIT: Wikipedia says that
Many bacteria can survive adverse conditions such as temperature, desiccation, and antibiotics by endospores, cysts, conidia or states of reduced metabolic activity lacking specialized cellular structures.
So at least some unicellular organisms can temporarily slow down the rate of metabolism.
I also think that some mammals can enter the state called hibernation, when their heart rate significantly decreases. I think this is different from above in that the amount of time mammals can spend in this state is less than the amount of time bacteria can spend in the dormant state (see here). From this I infer that the maximum metabolism slow-down factor is lower in mammals than in bacteria.
Ultimately, I am interested in learning how far we could push, via artificial means, the slow-down factor in complicated organisms like mammals. However, taking an entire organ and making all of its cells to go to sleep and then waking all of them up in an organized way seems to be much harder than achieving the same for a single cell. Thus my question: can we, in a reversible and controlled way, slow down the metabolism within a single human cell? What is the maximum slow-down factor then?