Dear Ahmed,

PC12 is an ideal cell line for testing the neuroprotection and neural differentiation potential of compounds. Apart from cell survival assays you can do lot more things. Since these cells are not adult neurons, you can observe the neuronal differentiation potential after inducing them with dietary polyphenols. In that case, you can measure the length of neurite extension in control and treated cells, qPCR and also go for the expression of protein markers of mature neurons like MAP2, NFM etc. by Immunofluorescence and western blotting. You might find the paper published by our group helpful regarding same because we have done similar experiments for stem cell secretome on pre-neuroblastic cell line IMR32. But PC12 is ideal for you since you are also going for in vivo animal model and these cells have animal origin.

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For in vivo, you can induce any neurodegenerative disease into animals like Parkinson's and Alzheimer's and there are array of protocols available regarding same. It doesn't even take much time since models are established within one week. Then you can do a rigorous characterization of neuroprotective effect because the protocols are very well established for such neurodegenerative diseases. In brief, you can test the cognitive functions by functional assays (there are many), blood brain barrier integrity by Evan's blue and morphology and survival of neurons in brain before and after treatment with various antibodies. You can also go for brain related gene array before and after treatment with your dietary polyphenols.

Feel free if you need any further advice.

Hope it helps!