Pushing a walker through a television studio in central Tokyo earlier this week, Tetsuko Kuroyanagi slowly climbed three steps onto a sound stage with the help of an assistant who settled her into a creamy beige Empire armchair.

A stylist removed the custom-made sturdy boots on her feet and slipped on a pair of high-heeled mules. A makeup artist brushed her cheeks and touched up her blazing red lipstick. A hairdresser tamed a few stray wisps from her trademark onion-shaped hairstyle as another assistant ran a lint roller over her embroidered black jacket. With that, Ms. Kuroyanagi, 90, was ready to record the 12,193rd episode of her show.

As one of Japan’s best-known entertainers for seven decades, Ms. Kuroyanagi has interviewed guests on her talk show, “Tetsuko’s Room,” since 1976, earning a Guinness World Record last fall for most episodes hosted by the same presenter. Generations of Japanese celebrities across film, television, music, theater and sports have visited Ms. Kuroyanagi’s couch, along with American stars like Meryl Streep and Lady Gaga; Prince Philip of England; and Mikhail Gorbachev, the former leader of the Soviet Union. Ms. Kuroyanagi said Gorbachev remains one of her all-time favorite guests.

Ms. Kuroyanagi, who jokes that she wants to keep going until she turns 100, is known for her rapid-fire chatter and knack for drawing out guests on topics like dating, divorce and, now, increasingly, death. Even as she works to woo a younger generation — the Korean-Canadian actor and singer Ahn Hyo-seop, 28, appeared on the show this month — many of her guests these days speak about the ailments of aging and the demise of their industry peers.