MSCs: what’s in a name?

Whether they are "stem" or "stromal", from adult tissues or from umbilical cord blood, MSCs are being used for a lot of clinical trials. Read more

Mopping up immune troublemakers after transplant

Memory CD8+ T cells play an important role in kidney transplant rejection, and they resist drugs that would otherwise improve Read more

Tracking a frameshift through the ribosome

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arthritis

COX-2 and epilepsy: it’s complicated

How much is the development of epilepsy like arthritis?

More than you might expect. Inflammation, or the overactivation of the immune system, appears to be involved in both. In addition, for both diseases, inhibiting the enzyme COX-2 initially looked like a promising approach.

Ray Dingledine, PhD

COX-2 (cyclooxygenase 2) is a target of traditional non-steroid anti-inflammatory drugs like aspirin and ibuprofen, as well as more selective drugs such as Celebrex. With arthritis, selectively inhibiting COX-2 relieves pain and inflammation, but turns out to have the side effect of increasing the risk of heart attack and stroke.

In the development of epilepsy, inhibiting COX-2 turns out to be complicated as well. Ray Dingledine, chair of pharmacology at Emory, and colleagues have a new paper showing that COX-2 has both protective and harmful effects in mice after status epilepticus, depending on the timing and what cells the enzyme comes from. Status epilepticus is a period of continuous seizures leading to neurodegeneration, used as a model for the development of epilepsy.

Postdoc Geidy Serrano, now at the Banner Sun Health Research Institute in Arizona, is first author of the paper in Journal of Neuroscience. She and Dingledine were able to dissect COX-2’s effects because they engineered mice to have a deletion of the COX-2 gene, but only in some parts of the brain.
They show that deleting COX-2 in the brain reduces the level of inflammatory molecules produced by neurons, but this is the reverse effect of deleting it all over the body or inhibiting the enzyme with drugs.

Four days after status epilepticus, fewer neurons are damaged (bright green) in the neuronal COX-2 knockout mice.

Dingledine identified two take-home messages from the paper:
First, COX-2 itself is probably not a good target for antiepileptic therapy, and it may be better to go downstream, to prostaglandin receptors like EP2.
Second, the timing of intervention will be important, because the same enzyme has opposing actions a few hours after status epilepticus compared to a couple days later.

More of Dingledine’s thinking about inflammation in the development of epilepsy can be found in a recent review.

Posted on by Quinn Eastman in Neuro Leave a comment

Biomaterials used for hips and knees

Orthopaedics is a constantly evolving subspecialty where medical technology and research drives the development of new products used for reconstruction of body parts, specifically for hip and knee replacements.

Emory has been on the forefront of investigating and using three materials for these replacements: ceramic on ceramic surfaces, metal on metal surfaces, or highly cross-linked polyethylene. These newer biomaterials can reduce wear rates by over 99 percent compared to previous materials, thus enhancing the life of the new hip or knee.

Adult reconstruction or hip and knee arthritis surgery delivers quality outcomes that make a dramatic improvement in a patient’s quality of life. At the first post-operative visit, patients are more comfortable, have less pain and are even more functional than before their surgery.

Orthopeadic surgeon James R. Roberson, MD, chairman, Department of Orthopaedics in Emory School of Medicine, and professor of orthopaedic surgery specializes in adult reconstructive surgery of the hip and knee.

Roberson has been involved in clinical research for more than 20 years to solve difficult problems of the arthritic hip and knee. He pioneered a minimally invasive surgery technique for knee replacement that allows him to use smaller incisions in certain patients who have uncomplicated conditions.

Visit Emory University Orthopaedics & Spine Center and Emory University Orthopaedics & Spine Hospital to learn more about orthopaedic services and watch a video about the hospital.

Posted on by Kathi Baker in Uncategorized Leave a comment