"None of the Clintons have ever taken a salary and don't profit from the foundation," Craig Minassian, the Clinton Foundation's chief communications officer, told MSNBC.
Donald Trump and Republicans have targeted the foundation, charging that it served as a conduit for access to Clinton's State Department.
"This is an example of pay-to-play politics the American people are sick and tired of," Mike Pence, Trump's running mate, told CNN's Jake Tapper Sunday on "State of the Union."
The Clintons, while denying any wrongdoing, have planned a series of changes -- including refusing to accept foreign and corporate contributions and shifting some of its programs to other charities -- designed to reduce appearances of impropriety if Hillary Clinton wins the 2016 presidential race.
Still, Minassian insisted the foundation's work isn't being reduced.
"We're not trying to wind it down. What we're trying to do is transition the program," he said, acknowledging that "obviously there's a different environment now -- a different media environment; a different set of criticisms and critiques."
Minassian's comments come amid a fresh foundation-related controversy for Clinton: Newly released emails show State Department aide Huma Abedin and then-top Clinton Foundation official Doug Band discussed getting representatives of foundation donors seats to an official lunch with Chinese President Hu Jintao.
UBS CEO of private wealth management Bob McCann, Rockefeller Foundation president Judith Rodin and Western Union CEO Hikmet Ersek were listed in Band's December 2010 email to Abedin.
"I'll ask," she responded.
Nearly two weeks later, Band followed up specifically about Rodin, emailing Abedin: "Can we get her at Biden's table?"
A representative of Ersek told CNN he didn't end up getting an invitation and did not attend. Others have not yet responded to CNN's inquiries about their attendance.
The emails were obtained by the conservative group Citizens United and first reported by ABC News
"As the State Department said last week, 'the Department's actions under Secretary Clinton were always taken with the intent to advance our foreign policy interests and with no other intent in mind than that,' " Clinton spokesman Josh Schwerin told CNN, citing State Department spokesman Mark Toner's comments to reporters last week.
"State also made clear that department officials 'are in touch with a wide range of outside individuals, organizations, nonprofits, NGOs, think tanks,' and others as part of normal business," Schwerin said. "Citizens United is a right-wing group that's been attacking the Clintons since the 1990s and, once again, is trying to make something out of nothing."
A State Department spokeswoman also said the department found nothing inappropriate about the emails.
"The State Department does not believe it is inappropriate for the administration to consider individuals suggested by outside organizations when deciding who to invite to an official function," State Department Director of Press Relations Elizabeth Trudeau said in a statement.
In another email forwarded by Band to Abedin, businessman and Clinton Foundation donor Gerardo Wertheim praises a rabbi the US ambassador in Malta is going to meet with, with Band calling Wertheim a "great friend" and "big supporter."
Abedin then forwarded the email to a State Department official asking for the ambassador's assistant to be told that the rabbi is "recommended by Gerardo Wertheim who is good friend and foundation supporter of President Clinton. Just want to pass along for info. No need for action. Thank you."
Minassian said in a statement the emails "aren't related to the Clinton Foundation's work improving lives around the world."
Some Democrats have acknowledged that the Clinton Foundation is fair territory to explore.
"I think there's legitimate questions about the Clinton Foundation," former Barack Obama campaign manager David Plouffe said on NBC's "Meet the Press" Sunday, though he added that Trump's business dealings are more problematic and the foundation has done good work.
Pence blasted Clinton over those meetings, telling Tapper: "The simple fact is, this is becoming more and more clear through direct evidence in these emails that State Department officials under Secretary of State Clinton were extending access and special favors to major donors of the Clinton Foundation," Pence said.
Donna Brazile, the interim Democratic National Committee chairwoman, defended Clinton from criticism over the foundation's influence Sunday on CBS' "Face the Nation."
"When Republicans meet with their donors, with their supporters, their activists, they call it a meeting. When Democrats do that, they call it a conflict," Brazile said.