I am not the best linux engineer but I believe that you can do that by using the chown command.
Chown is used to change the ownership of a file or directory to a specific user. In your case you can
which will give the ownership of the file to the superuser. Setting the case that your file is a textfile you can view this file using the following command
When you execute this command you will be prompted for the root password in order to view the file.
Hope this helps.