CLA Could Target Diabetes

Researchers at Penn State, University Park, have discovered that conjugated linoleic acids (CLA), naturally occuring in dairy and ruminant meats, have successfully treated diabetes in mice and have also shown promising results in human trial. This could provide sufferers with a new way of potentially treating the disease without using synthetic drugs.

CLAs are "predominantly found in dairy products such as milk, cheese and meat, and are formed by bacteria in ruminants that take linoleic acid--fatty acids from plants--and convert them into conjugated linoleic acids, or CLA," says Jack Vanden Heuvel, professor of molecular toxicology in Penn State's College of Agricultural Sciences and co-director of Penn State's Center of Excellence in Nutrigenomics.

CLA piqued interested when studies showed it inhibited certain cancers in mice, and further research showed that it affected cardiovascular health factors, such as circulating cholesterol and inflammation. These effects are similar to those of synthetic drugs now used to treat diabetes, which trigger nuclear receptors called PPAR. These receptors are members of a family of proteins that sense fatty acids and fatty-acid metabolites within cells. The drugs turn on the receptor, which ultimately increases the enzymes that process fatty acids and increases the tissues' sensitivity to insulin. The researchers theorized CLA might use the same mechanism.

Results of testing on mice showed CLA improved insulin action and decreased circulating glucose in a manner similar to that of the drugs. "Antidiabetes drugs act the same way. They mimic the natural activators of the receptors by getting into the cell and interacting with the PPARs to regulate glucose and fat metabolism," says Vanden Heuvel.

Initial human trials indicate that, when taken for longer than 8 weeks, CLA improves insulin misregulation and lowers blood-glucose levels in subjects with Type 2 diabetes. However, Vanden Heuvel cautions that, while a diet high in dairy and meat products might increase CLA intake, it might also raise intake of other, less-healthy lipids, such as saturated fatty acids. Instead, he recommends taking CLA as a dietary supplement or in CLA-fortified foods.

"Adult-onset diabetes is fast becoming an epidemic and is largely associated with poor diet and nutrition and other lifestyle issues," Vanden Heuvel says. "And compared to the synthetic drugs used to treat this disease, CLA does not cause weight gain and may in fact decrease overall body fat."