The recurring theme seems to be the fight to stay young. There is also the theme of narcissism which in this case is the fatal flaw of Dorian Grey.
Our culture is all about trying to stay young. One of the biggest industries right now is the cosmetic industry, and it thrives on making people want to look and feel younger. There are also a lot of people who are experiencing what is known as "Peter Pan Syndrome". These are the people who refuse to grow up both physically and emotionally. These people can oftentimes be seen living with their parents and holding an entry level job barely making money to keep themselves afloat. This stems from the dear of getting old and separating from their parents.
All of this is motivated by our fear of death. Death is feared oftentimes because we don't truly know what lies behind death's door. This makes us extremely uneasy and scared of death. We don't cope with inevitability too well. So this whole story is about one man's fear of death and just how far he goes to postpone his death, however in the end everyone must die. Whether or not you fill yourself with silicone and chemicals to make yourself look younger and tighter, death will always be there to greet you after a long day of pretending to be younger.