Nearly two-thirds of adults ages 18 to 29 believe that when someone “frequently forgets familiar names,” that person is old. The next most frequent “marker of old age” in the same survey was “bladder control problems”! As an indicator that “wisdom often comes with age” it is worth noting that “less than half of all adults ages 30 and older agreed”.
News releases and internet blogs this week are full of buzz about a protein that apparently is related to the memory loss of aging; something I call Somezhiemer’s as opposed to Allzhiemer’s (sic). In this Columbia University School of Medicine study a deficiency of the protein RbAp48 in a specific part of the brain in both older mice and 8 older humans (both postmortem) was correlated with memory loss ; at least the ability of the mice to remember a water maze pathway. A 50% decrease of the RbAp48 protein in the brain tissue was the only measurement that was significantly related to memory loss. To clinch the validity of the association they gave RbAp48 to old mice and showed that they began doing as well in the maze as the young mice.
Initially, researchers believed that age-related memory loss is an early manifestation of Alzheimer’s, but since mice do NOT get Alzheimer’s the “study provides compelling evidence that age-related memory loss (aka Somezhiemer’s) is a syndrome in its own right, apart from Alzhiemer’s”.
“There’s been a lot of hand wringing over the failures of drug trials based on findings from mouse models of Alzheimer’s. Whether these compounds will work in humans is not known. But the broader point is that to develop effective interventions, you first have to find the right target. Now we have a good target, and with the mouse we’ve developed, we have a way to screen therapies that might be effective, be they pharmaceuticals, nutraceuticals, or physical and cognitive exercises”, concluded one of the study’s authors, who was obviously trying to be politically correct by not just listing “pharmaceuticals”.
Before you rush out and try to identify the company, and its stock, that will bring RbAp48 to market, remember how preliminary these results are and how complex the research is. The RbAp48 protein is manufactured by one of the seventeen genes that they studied. Each gene (many comprised of more than 400 amino acid building blocks) controlled the manufacturing of a large number of proteins. Here is a brief excerpt from one of the referenced studies:
“Schmit et al. (2007) identified RBAP48 as a subunit of the over 669-kD LIN complex. Other stable LIN complex components included LIN9 (609375), LIN37, LIN54 (613367), and BMYB (MYBL2; 601415). All endogenous or epitope-tagged LIN complex subunits coimmunoprecipitated with one another, and all were efficiently codepleted together with antibodies directed to LIN9. The LIN complex associated with E2F (see 189971)-regulated promoters in the T98G human glioblastoma cell line and was required for activation of G2/M genes. Depletion of LIN complex subunits had no significant effect on expression of G1/S genes.”
Any questions?
The new study is “very impressive” and an important piece of the puzzle in understanding the molecular mechanisms of age-related memory loss, says Molly Wagster, Chief of the Behavioral and Systems Neuroscience Branch at the National Institute on Aging in Bethesda, Maryland. But she cautions that it involved a limited number of brain tissues and focused solely on one brain region, noting that other brain regions could also play an important role in age-related memory decline. “Further efforts will be needed to see if what the group has seen in rodents translates to humans.”
The good news is that one specific biological cause of memory loss has been discovered, as contrasted with speculation about aluminum, cooper, mercury, zinc, and other environmental agents.
The bad news is that us older people will probably not, in our lifetime, be able to take a “RbAp48 pill” each morning, so we don’t lose our car keys, glasses or …. forget an August 15 blog.
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