For sure, both GH and IGF are potent neurotrophic and neuroprotective factors in the brain.
RhGH was even shown, in mice that were injected with the Aβ-peptide, in order to simulate AD, to have broad effects in ameliorating a lot of AD's negative effects. And AD and Parkinson's patients both have lowered IGF levels, right? GH is suma sumarum also very anxiolytic, reducing inflammation, so I'd say it's use with aas is for sure of some help in reducing aas induced depressive state, hyperactive amygdala, etc. Imho, rhGH is a good idea as an addon to a aas cycle, purely for the reason of neuro health.
Now, the question is; do all the positive effects of GH when combined with the negatives of insulin resistance it causes, lead to a net positive outcome in regards to loss of dopaminergic neurons? Idk how up to date you are on insulin and dementia, AD, PD, .. but this is imo a great summation on the topic:
The Relevance of Insulin Action in the Dopaminergic System
Be interested in hearing your thoughts on long term supraphysiological dosages of rhGH, for bodybuilding purposes, and it's potential negatives, specifically attributed to insulin resistance. I'd assume it's positives can't negate it's negatives in a longer run? Especially in a hypercaloric, carb heavy diet ...
For me personally, being an add person with GAD, I can't run normal aas dosages without a low dose ssri. But the ssri worsens my adhd so much, that I can't even read 3 sentences, without switching to 10 different thought processes while trying to focus on the task at hand. So, I stick to low, trt+ dosages. Also, aas really worsen my impulsivity and novelty seeking behavior. Which got me thinking, do aas upregulate D2 signaling? I know there's a bimodal relationship between dopamine and test, just not quite sure how that works up all together ...
Anyway, I wanted to add, that the aas using population is heavy in drug addictive personalities, ie. it's heavy with users who have problems in their reward systems and thus don't have the most stable brain chemistry as is. Statistics show, for instance, that adhd patients are much much more likely to end up abusing rec drugs which also means aas for that matter. So I always wanted to do more research and present a workflow on how to ameliorate aas detrimental effects on brain chemistry. But the vast majority of aas using population really aren't biohackers but are on much more self destructive path and idk if they really do care. But I bet that people would start caring if they were made clear, how disruptive aas really are for their personalities and brain health. Anyway, I'm rambling, long day ...