Browsing by Author "Wallace, Taylor C."

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    Avenanthramides Prevent Osteoblast and Osteocyte Apoptosis and Induce Osteoclast Apoptosis in Vitro in an Nrf2-Independent Manner
    (MDPI, 2016-07-11) Pellegrini, Gretel G.; Morales, Cynthya C.; Wallace, Taylor C.; Plotkin, Lilian I.; Bellido, Teresita; Department of Anatomy & Cell Biology, IU School of Medicine
    Oats contain unique bioactive compounds known as avenanthramides (AVAs) with antioxidant properties. AVAs might enhance the endogenous antioxidant cellular response by activation of the transcription factor Nrf2. Accumulation of reactive oxygen species plays a critical role in many chronic and degenerative diseases, including osteoporosis. In this disease, there is an imbalance between bone formation by osteoblasts and bone resorption by osteoclasts, which is accompanied by increased osteoblast/osteocyte apoptosis and decreased osteoclast apoptosis. We investigated the ability of the synthethic AVAs 2c, 2f and 2p, to 1-regulate gene expression in bone cells, 2-affect the viability of osteoblasts, osteocytes and osteoclasts, and the generation of osteoclasts from their precursors, and 3-examine the potential involvement of the transcription factor Nrf2 in these actions. All doses of AVA 2c and 1 and 5 µM dose of 2p up-regulated collagen 1A expression. Lower doses of AVAs up-regulated OPG (osteoprotegerin) in OB-6 osteoblastic cells, whereas 100 μM dose of 2f and all concentrations of 2c down-regulated RANKL gene expression in MLO-Y4 osteocytic cells. AVAs did not affect apoptosis of OB-6 osteoblastic cells or MLO-Y4 osteocytic cells; however, they prevented apoptosis induced by the DNA topoisomerase inhibitor etoposide, the glucocorticoid dexamethasone, and hydrogen peroxide. AVAs prevented apoptosis of both wild type (WT) and Nrf2 Knockout (KO) osteoblasts, demonstrating that AVAs-induced survival does not require Nrf2 expression. Further, KO osteoclast precursors produced more mature osteoclasts than WT; and KO cultures exhibited less apoptotic osteoclasts than WT cultures. Although AVAs did not affect WT osteoclasts, AVA 2p reversed the low apoptosis of KO osteoclasts. These in vitro results demonstrate that AVAs regulate, in part, the function of osteoblasts and osteocytes and prevent osteoblast/osteocyte apoptosis and increase osteoclast apoptosis; further, these regulatory actions are independent of Nrf2.
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    Recommendation on an updated standardization of serum magnesium reference ranges
    (Springer, 2022-06-10) Rosanoff, Andrea; Wes, Christina; Elin, Ronald J.; Micke, Oliver; Baniasadi, Shadi; Barbagallo, Mario; Campbell, Emily; Cheng, Fu-Chou; Costello, Rebecca B.; Gamboa-Gomez, Claudia; Guerrero-Romero, Fernando; Gletsu-Miller, Nana; von Ehrlich, Bodo; Iotti, Stefano; Kahe, Ka; Kim, Dae Jung; Kisters, Klaus; Kolisek, Martin; Kraus, Anton; Maier, Jeanette A.; Maj-Zurawska, Magdalena; Merolle, Lucia; Nechifor, Mihai; Pourdowlat, Guitti; Shechter, Michael; Song, Yiqing; Teoh, Yee Ping; Touyz, Rhian M.; Wallace, Taylor C.; Yokota, Kuninobu; Wolf, Federica; the MaGNet Global Magnesium Project (MaGNet); Epidemiology, School of Public Health
    Purpose Serum magnesium is the most frequently used laboratory test for evaluating clinical magnesium status. Hypomagnesemia (low magnesium status), which is associated with many chronic diseases, is diagnosed using the serum magnesium reference range. Currently, no international consensus for a magnesemia normal range exists. Two independent groups designated 0.85 mmol/L (2.07 mg/dL; 1.7 mEq/L) as the low cut-off point defining hypomagnesemia. MaGNet discussions revealed differences in serum magnesium reference ranges used by members’ hospitals and laboratories, presenting an urgent need for standardization. Methods We gathered and compared serum magnesium reference range values from our institutions, hospitals, and colleagues worldwide. Results Serum magnesium levels designating “hypomagnesemia” differ widely. Of 43 collected values, only 2 met 0.85 mmol/L as the low cut-off point to define hypomagnesemia. The remainder had lower cut-off values, which may underestimate hypomagnesemia diagnosis in hospital, clinical, and research assessments. Current serum magnesium reference ranges stem from “normal” populations, which unknowingly include persons with chronic latent magnesium deficit (CLMD). Serum magnesium levels of patients with CLMD fall within widely used “normal” ranges, but their magnesium status is too low for long-term health. The lower serum magnesium reference (0.85 mmol/L) proposed specifically prevents the inclusion of patients with CLMD. Conclusions Widely varying serum magnesium reference ranges render our use of this important medical tool imprecise, minimizing impacts of low magnesium status or hypomagnesemia as a marker of disease risk. To appropriately diagnose, increase awareness of, and manage magnesium status, it is critical to standardize lower reference values for serum magnesium at 0.85 mmol/L (2.07 mg/dL; 1.7 mEq/L).
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    The magnesium global network (MaGNet) to promote research on magnesium in diseases focusing on covid-19
    (JLE, 2021) Wolf, Federica I.; Maier, Jeanette A.; Rosanoff, Andrea; Barbagallo, Mario; Baniasadi, Shadi; Castiglioni, Sara; Cheng, Fu-Chou; Colaneri Day, Sherrie; Costello, Rebecca B.; Dominguez, Ligia J.; Elin, Ronald J.; Gamboa-Gomez, Claudia; Guerrero-Romero, Fernando; Kahe, Ka; Kisters, Klaus; Kolisek, Martin; Kraus, Anton; Iotti, Stefano; Mazur, Andre; Mercado-Atri, Moises; Merolle, Lucia; Micke, Oliver; Gletsu-Miller, Nana; Nielsen, Forrest; O-Uchi, Jin; Piazza, Ornella; Plesset, Michael; Pourdowlat, Guitti; Rios, Francisco J.; Rodriguez-Moran, Martha; Scarpati, Giuliana; Shechter, Michael; Song, Yiqing; Spence, Lisa A.; Touyz, Rhian M.; Trapani, Valentina; Veronese, Nicola; von Ehrlich, Bodo; Vormann, Juergen; Wallace, Taylor C.; CMER Center for Magnesium Education, Research; Gesellschaft für Magnesium-Forschung e.V. Germany; SDRM Society (International Society for the Development of Research on Magnesium); Epidemiology, School of Public Health