Congratulations to Shouan on being selected by the OMRF Postdoc Training Committee for a travel award to attend the Cell Press symposium on “Aging and Metabolism” in Sitges, Spain this September. Way to go!!
Chondrocytes are mechanosensitve cells that respond to changes in the environment to maintain articular cartilage homeostasis. One potential mechanosensitive feedback system involves enzymes and signaling mechanisms that balance the reducing and oxidizing (i.e., “redox”) conditions of the cell.
We found that cyclic compressive loading of healthy bovine cartilage alters the endogenous cartilage antioxidant network. Higher compressive stress (40% strain) increased glutathione oxidation and caused a reduction in the expression of the rate-limiting enzymes for glutathione synthesis. Higher stress also increased the expression of the mitochondrial antioxidant SOD2 while decreasing the cytosolic isoform SOD1, consistent with mitochondrial-derived ROS production at higher loads. Moderate compressive stress (15% strain) caused glutathione oxidation as well, but it also increased total glutathione content and upregulated SOD1 gene expression. Pro-oxidant conditioning of cartilage using tBHP increased glutathione content without altering any other loading-associated changes. These findings suggest that glutathione synthesis, more than antioxidant enzyme upregulation, is a central pro-oxidant and mechanosensitive mediator of antioxidant defense in chondrocytes.
We lost two lab members this summer but for great reasons.
Elise accepted a faculty position at the Oregon Institute of Technology where she will be an Assistant Professor in the Department of Natural Sciences (Biology-Health Sciences Program). Elise started her new position in September.
Aaron left the lab in August to pursue his PhD in Chemical and Biological Engineering at the University of Wisconsin.
Elise and Aaron made a great team, and they will be missed. Good luck to both of them!
We were excited to host Dr. Chaofan Zhang from the University of Hong Kong in our lab for a week in May. Chaofan visited us after attending the OARSI meeting in Las Vegas, where he was honored with a plenary presentation as one of the nine highest rated abstracts by a Young Investigator. Dr. Zhang wanted to share the following comments on his visit: “I was honored to have an opportunity to visit Dr. Griffin’s lab from May.1-5. During this week, I visited their lab facilities, attended several seminars, and had deep discussions with the whole team and other scientists from the Aging & Metabolism program. It was such a fruitful trip. Everyone there was helpful to me. I am really thankful to Dr. Griffin for providing this opportunity. His exhaustive knowledge, patience and kindness always motivated me.” Thank you for the kind comments!
The Humphries and Griffin Labs are excited to have Dr. Albert Batushansky join the Aging and Metabolism Program to lead our metabolomics research. Albert received his PhD in Life Science from The Jacob Blaustein Institutes for Desert Research at the Ben-Gurion University in Negev, Israel. This is where he developed his expertise in plant metabolomics and “-omics” data integration and network analysis. He joined us most recently from Dr. Angelovici’s lab at the University of Missouri so he can pursue his passion in biomedical metabolomics research at OMRF. Welcome Albert!
Elise Donovan and Erika Barboza Lopes each had their abstracts selected for podium presentations at the 2017 Annual Meeting of the Osteoarthritis Research Society International (OARSI) this April in Las Vegas, NV. The title of Elise’s presentation is “HIGH FAT AND HIGH SUCROSE DIETS IN MICE HAVE INDEPENDENT EFFECTS ON OSTEOARTHRITIS PATHOLOGY AND CHONDROCYTE METABOLIC STRESS.” Erika’s title is “EXERCISE INDUCES TRANSIENT INFLAMMATORY AND PROFIBROTIC REMODELING OF THE INFRAPATELLAR FAT PAD.” Congratulations Elise & Erika!!
The Griffin Lab hosted Dr. Eric Verdin on February 16th as the OMRF Research Forum speaker. Dr. Verdin recently took over as President and CEO of The Buck Institute for Research on Aging, and we were grateful that he fit us into his busy schedule. Dr. Verdin was a gracious guest. He shared many insights into sirtuins, acetylation, and aging, and he delivered an excellent seminar titled, “Metabolism, Epigenetics and Aging: A growing Nexus.”
Dr. Shouan Zhu joined the lab as a post-doctoral fellow in January of 2017. Shouan completed the first 3 years of his Ph.D. at the Center for Stem Cell & Tissue Engineering in Zhejiang University China under supervision of Dr. Hong Wei Ouyang. He earned a prestigious fellowship that allowed him to complete the 4th and 5th years of his Ph.D. research overseas. For this he joined the Department of Orthopedic Surgery at Johns Hopkins University, working on the mechanism of osteoarthritis pain under the supervision of Dr. Xu Cao. We’re excited to have Shouan join us, and we look forward to his exciting new discoveries!!
Our summer NARCH student, Hannah Taff, is back with us during her winter break from East Central University. Hannah is finishing analyzing knee samples from our collaborator, Ted Garland. She presented her initial findings this summer at UC Berkeley as a McNair Scholar. During the next two weeks she’ll finish analyzing changes in the cartilage and subchondral bone.