Speculative Fact #149: Do you want to live forever?

Scientists have turned geriatric mice into college age mice by taking chemicals key to the aging process called NADDs, and bringing them down to 20-something levels.   Now of course there's plenty of ways you can use this little tidbit in a story about human immortality, but what if the process were used on us and human NADDs were used to sustain the immortality of another creature, like our alien overlords that look suspiciously like rodents? 

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