They appear with knee pain, bone pain, lack of memory, etc. But in addition to all this, several biologists from the Salk Institute of San Diego have studied in California another lack of the cell nuclei of older people. They have found that the pores of their cell nuclei weaken. These pores play a fundamental role: they control the molecules that enter and exit the nucleus.
Each pore is made up of approximately 30 nucleoporic proteins that control what enters and leaves the nucleus.
Each time a cell divides, this cell renews the pores of the nucleus. What happens is that in older people most cells do not divide. In these cells there is intermittent replacement of some nucleopus, while the rest is not replaced and when aging does not adequately fulfill its function. For example, they have seen that the core of a major rat lets a molecule pass too heavy to pass through these pores.
They are not yet very clear about the relationship between these pores and age, but they believe that introducing certain proteins into the nucleus can alter genetic activity.