When using the Microsoft Word AddIn to send mailings as PDFs to email addresses, Acrobat offers to enter a mail subject and body.
In the German version of Acrobat the suggested text even contains a German umlaut (like ä,ö,ü). This umlaut get's replaced by a ? at the recipients end. E-Mail was sent from one Office 365 account to another Office 365 account, both using current Outlook version.