Stars from TV, movies, music and Broadway, many of whom have a personal connection to the disease that afflicts 5.4 million Americans and is the sixth leading cause of death in the U.S., joined forces to raise money for Alzheimer's research at the 19th annual "A Night at Sardi's" benefit, performing selections from Cole Porter's song catalogue in the revue "Red Hot & Cole." We caught up with some of them on the red carpet, including host Seth Rogen, emceeing for the second time. "I know that it's a good crowd and they're ready to laugh, and no matter what I do, the people who sing will be really good so no one will be worried about me if I suck," he laughed. Joking that he "stopped doing laundry altogether" to be more green, Rogen will reprise his role as the voice of Mantis in "Kung Fu Panda 2," due out May 26, and is about to start "My Mother's Curse," a road trip movie with Barbra Streisand playing his mom.

"Private Practice"'s Audra McDonald, who has a garden and composts at her home in New York, showed off her gorgeous soprano voice on a medley of "So in Love" and "I Happen to Like New York." She'll spend her hiatus doing a summer concert tour, with selected dates leading up to it this spring, starting with a March 28 date at the Longacre Theatre in Manhattan. She's also working on a new CD. "The theme is flight," she said.

McDonald's "Private Practice" ex-husband Taye Diggs was suave and smooth on "It's All Right With Me," and Kevin McKidd of "Grey's Anatomy" was a welcome surprise, his lovely rendition of "Ev'ry Time We Say Goodbye" a highlight of the night. "I did a movie a few years ago with Kevin Kline called 'De-Lovely,' about Cole Porter," noted the Scotsman, whose grandmother and other family members had Alzheimer's. "Grey's" viewers will get the chance to hear McKidd (pictured right) sing in the March 31 episode, a musically themed show in which he'll sing "Chasing Cars" and "How We Operate" with co-stars. "At this point it's nice for us to change it up and do something different," he said. As for the season finale, "It's not quite on the same scale as last year's, but it'll leave a lot of question marks for next season."

McKidd, who recycles at home, may shoot a movie in the U.K. during his hiatus, and will accompany a pediatric surgeon friend to Mozambique on a humanitarian mission.

"The older we get, the more people we find out have it," said Scott Bakula, who has family and friends affected by Alzheimer's. Part of the "Another Op'nin'" opening number, he's been the beneficiary of his wife's green thumb. "She has an organic garden and grows all kinds of lettuces and tomatoes. Last night she went out and got celery for the salad," said Bakula, whose TNT series "Men of a Certain Age" returns June 1. Although he wouldn't spill specifics, "There's a lot of up and down relationship mayhem," he hinted.

"I definitely want to get an eco-friendly car one day," said Cheryl Burke, whose friend has an electric vehicle and loves it. She and fellow "Dancing With the Stars" pro Maksim Chmerkovskiy did an appropriately steamy dance to accompany Vanessa Williams' performance of "Too Darn Hot," another show highlight. Burke is partnered with wrestler Chris Jericho this season on "DWTS," and weighed his strengths and weaknesses. "His biggest weakness is his posture. He's so built and so strong that sometimes it looks like he doesn't have a neck. But he picks up on choreography really fast. He has a musical background, he's so great and positive, and he's used to wearing spandex,” enumerated Burke, who is readying a shoe line for HSN. "It'll be the comfort of a dance shoe but with heels that are really comfortable to wear all day."

Matt Lanter, whose grandmother suffered from Alzheimer's, felt compelled to lend his support. "Most people are touched by it, and if they're not, they will be soon enough. It's important that we know about it," said the "90210" star, who does his eco part by turning off unneeded lights and recycling. "The little things that we all can do add up." His series returns to the CW April 18 with a spring break episode that takes place (but alas, wasn't shot in) Cabo San Lucas. "We campaigned for it but it didn't happen," noted Lanter, but he's making up for it with a trip to Tahiti next week for a photo shoot and some R&R. "I'm taking my girlfriend along so it's a little business and a lot of pleasure."

"I'm a rock chick so to hear me sing a Cole Porter song it was almost like an evil scientist experiment," laughed singer Grace Potter, who performed a smoldering version of "I've Got You Under My Skin," dedicated to her grandfather, who had Alzheimer's. She and her band the Nocturnals will do scattered concert dates before heading out on the summer festival circuit, and she makes sure that they stay as green as possible on the road. "We like to play festivals that run on solar panels. And water bottles on the tour bus are the worst thing for the carbon footprint other than fuel, so we keep a huge jug on the counter and everyone refills their own cup with their name on it," noted Potter, who keeps it green at home too. "I'm from Vermont, where they're very into the green movement — lots of composting and recycling. My mom does the tomatoes and beans and all that stuff. I'm an herb garden girl. I keep it simple: rosemary and basil."

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A Night at Sardi's: Celebs sing to benefit Alzheimer's research
Seth Rogen hosted as stars from 'Grey's' to 'Dancing with the Stars' performed classic songs in the name of Alzheimer's research.