McPherson knew the 43-year-old Seau was busy in his post-playing days. "I also know he was a very charismatic guy and the limelight that shone on him was very bright. Even though he was busy, it could never match what he had."
Seau was described as upbeat and invincible.
A few weeks ago, a smiling Seau was videotaped playing a ukuelele and singing while attending the spring game at Southern California, where he starred before being drafted by the Chargers in 1990.
Mitchell said that friends of Seau's who were at his charity golf tournament a month ago said his "spirits were great."
During emotional remarks to reporters on Wednesday, Seau's mother, Luisa, said her son gave no indication of a problem when she spoke to him by phone earlier this week.
"He's joking to me, he called me a 'homegirl,'" she said.
Seau purchased his Oceanside home for $3.2 million in August 2005, near the peak of the housing boom in San Diego. Sharon Ferguson, assistant division chief in the San Diego County assessor's office, said there were no liens against his property.
If Seau was having trouble with something, he didn't let anyone know. Police said no suicide note was found.
Mitchell and McPherson wish Seau had reached out to somebody.
"I'm sorry to say, Superman is dead. All of us can appear to be super, but all of us need to reach out and find support when we're hurting," Mitchell said. "This super person, this wonderful human being, this extraordinary athlete and man, if someone so invincible like Junior could end his life this way, it should be a message to all of us all going through hurt and travails, that we all need each other. If somebody's hurting, please talk to somebody. Get help."
Further autopsy details, including results of toxicology tests, will be released in a final investigative report, which may take up to 90 days to complete.
The medical examiner's office said it was awaiting a decision by the family on whether to turn over Seau's brain to unidentified outside researchers for study.
Boston University's Center for the Study of Traumatic Encephalopathy has analyzed the brains of dozens of former athletes, including that of former Chicago player Dave Duerson, who shot himself in the chest last year.
While saying it was saddened by Seau's death, center officials would not say if they have reached out to the Seau family or would be interested in studying his brain.
Duerson's family has filed a wrongful death suit against the NFL, claiming the league didn't do enough to prevent or treat concussions that severely damaged Duerson's brain before he died in in February 2011.
Former Atlanta Falcons safety Ray Easterling, who had joined in a concussion-related lawsuit against the league — one of dozens filed in the last year — shot himself last month at age 62. His wife has said he suffered from depression and dementia after taking years of hits.
Seau is not known to have been a plaintiff in the concussion litigation.
AP Sports Writer Jimmy Golen in Boston contributed to this report.
Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.