Study shows direct link between leptin and obesity-related cardiovascular disease

Nov 10, 2008

Obese people who don't have high cholesterol or diabetes might think they're healthy – despite the extra pounds. But new Ohio University research suggests that obesity raises levels of the hormone leptin, which can be as big a threat to the cardiovascular system as cholesterol.

Tadeusz Malinski and colleagues have published the first study to directly observe how high levels of leptin can create a cascade of harmful biochemical changes in the body. Leptin, a peptide hormone produced by fat cells, helps regulate body weight by acting on the hypothalamus to suppress appetite and burn stored fat.

But an excess of fat in the body can produce too much of the hormone, which, in turn, can lower levels of bioavailable nitric oxide. Nitric oxide, produced by the endothelial cells, supports healthy cardiovascular function by relaxing blood vessels and maintaining good blood flow, explained Malinski, who has developed special nanosensors that can detect levels of the substance.

In addition, Malinski found that the high levels of leptin stimulate greater production of superoxide. It reacts with nitric oxide to create peroxynitrite, a very toxic molecule that can impact DNA replication and damage endothelial cells in the vascular system.

"The nanosensors provide a more direct method of determining what processes are occurring in the body. Previously, researchers didn't have a clear idea of how this works," said Malinski, the Marvin and Ann Dilley White Distinguished Professor of Biomedical Sciences at Ohio University.

The study, which examined the process in single human cells and also obese mice models, was published in a recent issue of the American Journal of Physiology – Heart and Circulatory Physiology.

Though obesity is closely associated with heart failure, scientists haven't fully understood the relationship, Malinski noted. The new study suggests that increased levels of leptin alone can cause long-term cardiovascular damage similar to hypertension, arthrosclerosis, diabetes and other disorders.

"Now that we know the exact molecules responsible for the damage, we can design a method to mollify the effect of obesity on the cardiovascular system," Malinski said.

Source: Ohio University

Explore further: Sierra Leone streets deserted as shutdown begins

add to favorites email to friend print save as pdf

Related Stories

Final pieces to the circadian clock puzzle found

5 hours ago

Researchers at the UNC School of Medicine have discovered how two genes – Period and Cryptochrome – keep the circadian clocks in all human cells in time and in proper rhythm with the 24-hour day, as well ...

A spray-on light show on four wheels: Darkside Scientific

7 hours ago

Darkside Scientific recently drew a lot of gazes its way in its video release of a car treated to the company's electroluminescent paint called LumiLor. Electroluminescence (EL) is a characteristic of a material ...

Measuring modified protein structures

9 hours ago

Swiss researchers have developed a new approach to measure proteins with structures that change. This could enable new diagnostic tools for the early recognition of neurodegenerative diseases to be developed.

Recommended for you

Sierra Leone streets deserted as shutdown begins

6 hours ago

Sierra Leone's normally chaotic capital resembled a ghost town on Friday as residents were confined to their homes for the start of a three-day lockdown aimed at halting the deadly Ebola epidemic.

Sierra Leone launches controversial Ebola shutdown

8 hours ago

Sierra Leone on Friday launched a controversial three-day shutdown to contain the deadly spread of the Ebola virus, as the UN Security Council declared the deadly outbreak a threat to world peace.

Cooling of dialysis fluids protects against brain damage

21 hours ago

While dialysis can cause blood pressure changes that damage the brain, cooling dialysis fluids can protect against such effects. The findings come from a study appearing in an upcoming issue of the Journal of the American So ...

Two Ebola vaccines to be tested in Switzerland

22 hours ago

Clinical trials of two experimental vaccines against the deadly Ebola virus are due to begin soon in Switzerland, the country's Tropical and Public Health Institute said on Thursday.

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

vlam67
not rated yet Nov 10, 2008
But an excess of fat in the body can produce too much of the hormone, which, in turn, can lower levels of bioavailable nitric oxide. Nitric oxide, produced by the endothelial cells, supports healthy cardiovascular function by relaxing blood vessels and maintaining good blood flow


...and nitric oxide is what makes and maintains a good erection. So being obese also means a great chance of being limp as well!