I continually have to review multiple articles, in multiple journals. These articles present how various enzymes, proteins, lipids, carbohydrates, etc. intervene in the processes that lead to certain pathologies (generally neurodegenerative). I have used Celldesigner and Freeplane, but Freeplane is very general software and CellDesigner provides reduced work spaces. I would like to know if there is any other free software that works for this purpose (I usually work in Linux).
Here is a list of such programs. It is an old post but most of the tools it lists appear to still be functional. I found this by just googling "celldesigner alternatives", which is always a good idea to search first for these things.
I have used cytoscape and it is ok, maybe too general also for your purposes. For very simple purposes I have used KEGG pathway in the past, which is in addition to the others.