Every newsletter service allows you to set a specific email address as the From: address seen by your readers. Take some time to pick a good one:
• DO NOT use @gmail.com, @aol.com, or @yahoo.com addresses. These providers publish a policy which says in essence, "if it did not originate from our servers, we didn't send it" and most receiving mail servers will either ignore such list messages or mark them as spam.
• The address needs to be one which does get read because any replies to your mailings will come to that address (including usually several Out-of-office autoreplies). A good way to do this is to configure a From: address which forwards to your real address(es).
• Don't use your personal email address. You may eventually have other authors or a different email address. Instead use a "role" address, something like editor@ or news@ then forward that alias to your real address.
• Try to avoid changing your From: address once it's been used. While spam filters don't initially give a lot of weight to the From: address, they DO if it is found in the recipient's contact list. So if your readers have previously whitelisted (put it in their contact list) your From: address, changing it may cause your next mailings to get filtered.