More than three decades ago, scientists discovered that a chemical found in a synthetic opioid, MPTP, induced the onset of a form of Parkinson’s disease. In a new study led by scientists from the School of Veterinary Medicine, researchers found that an enzyme in the body can metabolize compounds formed in the brain from alkaloids present in certain foods and tobacco into MPTP-like chemicals, triggering a neurodegenerative condition in mice.

The researchers, led by Narayan Avadhani and Mrittika Chattopadhyay, suggest that the enzyme, mitochondrial CYP2D6, presents a potentially powerful new target for Parkinson’s treatment.

“Over the past two or three decades, researchers have tried inhibiting the process by which they believed MPTP was metabolized, with mixed success,” says Avadhani. “We believe that mitochondrial CYP2D6 is the more direct drug target, which might prove better in treating idiopathic Parkinson’s disease.”

In a new study, Yale researchers offer insight into leptin, a hormone that plays a key role in appetite, overeating, and obesity. Their findings advance knowledge about leptin and weight gain, and also suggest a potential strategy for developing future weight-loss treatments, they said.

The study, led by investigators at Yale and Harvard, was published the week of June 17, 2019, in the Proceedings of the National Academy of Sciences.

Leptin, which is secreted by fat cells, informs the brain when fuel stored in body fat and in the liver is becoming depleted. It has not been well understood how low leptin concentrations in plasma — the largest component of blood — increase appetite. The researchers studied the biology of leptin in rodents. They also investigated the influence of nerve cells in the brain known as AgRP neurons, which regulate eating behavior.