Okay, I am going to give this another try, hopefully, this logline attempt is closer than my last one.
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“When his girlfriend (Love interest?) is ritually murdered, an atheist sheriff is forced to team with the local preacher’s daughter and the DEA, in order to follow the dark trail of a satanic syndicate, involved trafficking and human sacrifice.”

From what I am reading, what’s missing are the stakes.

It isn’t coming across in your logline, nor in your brief synopsis why living longer and aging slower is a bad thing.

What makes aging naturally the correct choice and worth fighting for? What makes a slower aging process bad enough it is worth fighting against?

I only say this because aging naturally vs aging using nanotechnology seems to be the dramatic question of your story.

At what point does the reader know that the 157-year-old woman is the key to anti-aging?

In the Wizard of Oz Dorothy has an inner journey. At the beginning of the film she just wants to get away from her small town, however, after all her adventures she realizes there is no place like home.

Dorothy also has an outward journey, After getting swept up by a tornado she must follow a yellow brick road to a wizard whom she is told can get her home.

Inner Journey logline:  “A small-town Kansas girl goes through a journey of self-discovery, and through a series of events and comes to the conclusion there is no place like home.”

outer Journey logline:  “When a tornado transports her to a magical land, a small-town Kansas girl must follow a yellow brick road in order to find the wizard with the power to get her home.”

If you were to read the inner journey logline, you would have no idea what the Wizzard of Oz is actually about.
Which is why most loglines are about the outer journey story. They are about the events that happen on the screen, not the feelings and thoughts the character is having.