Q: Is journal permission required for reproducing a figure?

If you are planning to just mention the figure without actually printing it in your paper or use the data to create a figure of your own, then you can merely cite the source. This is because data is freely available and has no copyright. 

However, if you are planning to use the same figure in your paper, you need to first get a permission from the journal. You should also mention in your paper that the figure is a reproduction and cite the source. According to the ICMJE guidelines on using illustrations, “If a figure has been published previously, acknowledge the original source and submit written permission from the copyright holder to reproduce it.”