London: In a pilot study on some of the oldest people of the world, researchers have identified that low blood levels of the peptide hormone are an indicator for good microcirculation that describes blood flow through the smallest vessels in the circulatory system and indicates an increased lifespan.
The study was designed to identify lifestyle, genetic and epigenetic factors contributing to longevity in the Cilento region of Italy that has one of the world's highest concentrations of centenarians -- even higher than in Okinawa (Japan), the most intensively investigated centenarian hotspot.
The researchers found that the perfusion of organs and muscles of the centenarians was as efficient as that in people who were 30 years younger.
Low blood levels of the peptide hormone Adrenomedullin (bio-ADM) are an indicator for such a good microcirculation, the findings showed.
"Very low concentrations of this biomarker indicate a well-functioning endothelial and microcirculatory system allowing good blood perfusion of organs and muscles," said one of the researchers Salvatore Di Somma from La Sapienza University in Rome.
A good microcirculation is what makes marathon runners perform better at the same heart rate than the average man or woman on the street.
Di Somma and his team carried out comprehensive health and life style assessments of two study groups that live in the Cilento region, located in the province of Salerno in southern Italy.
In the first were 29 so-called 'SuperAgers' (median age 92 years), while the second was made up of 52 younger relatives (median age 60 years, living in the same household) who are expected to live just as long because they have the same genetic background and have been exposed to the same environmental and lifestyle factors.
It measured levels of the heart-function biomarker MR-proANP, as well as a marker for kidney function (penKid) and bio-ADM.
The results were compared to those of a cohort of 194 healthy persons (median age 63.9 years).
Both heart function and kidney function biomarkers were elevated in the SuperAgers, possibly due to the process of organ aging.
In the group of SuperAgers, the bio-ADM values -- which are often pathologically elevated in heart failure or acute kidney injury patients -- were as low as those in both reference groups.
Results of the study were presented at a symposium in the Italian town of Pollica.