MEDICINE: THE WEIGHT HORMONE CAN REGULATE OUR IMMUNE SYSTEM

Leptine, a hormone regulating our body weight could play a key role in the etiopathology of serious immune diseases such as experimental multiple sclerosis (EAE, experimental allergic encephalitis) and autoimmune diabetes. This important discovery has been made by a team of researchers from the Institute of Endocrinology and Experimental Oncology of Consiglio Nazionale delle Ricerche from Naples (IEOS-CNR), that has published the results on Journal of Clinical Investigation. This study gives us new insights on the correlation between the body weight-regulating hormone and the capability of our body to defend itself against diseases. This correlation was brought to light for the first time in 1998 by the same Italian researchers and by an English team from the Hammersmith Hospital.

"Our study", explains Giuseppe Matarese, a researcher from the Immune-Endocrinology team of IEOS-CNR "started from a historical data: in wealthier countries there has been a significant drop in infections such as tuberculosis, diomycosis or parasitosis against a significant increase in automimmune diseases such as multiple sclerosis, rheumatoid arthritis or type 1° diabetes; on the other hand, in poor countries where food is scarce, the situation is exactly the opposite."

Starting from this assumption, CNR researchers have found out that obese rats with a low production of leptine showed a resistance to EAE induction. The administration of the hormone made them as vulnerable as normal, non-obese rats. Before developing the disease, normal rats vulnerable to EAE show an important increase in the production of leptine both in the serum and in the brain. A leptine drop in the same subjects, obtained after a 48-hour fast, could reduce the seriousness and the clinical symptoms of the diseases.

Hence, if the absence of leptine could favour the onset of infectious diseases, too much leptine, that is an excess of fat occurring mainly in wealthy nations, could explain at least partially, the increase in the rate of autoimmune diseases: "The action of leptine on experimental multiple sclerosis", underlines Matarese, "has been widely and exhaustively confirmed whereas we are still studying its effects on type 1° diabetes; however, our studies are producing similar results."

The results of the research could have a relevant impact both on the prevention and the treatment of multiple sclerosis and other autoimmune diseases.

For further information: Giuseppe Matarese: 347-2738870