Medical Genetics Commons^™

Metabolic And Molecular Insights Into An Essential Role Of Nicotinamide Phosphoribosyltransferase., Li Q. Zhang, Leon Van Haandel, Min Xiong, Peixin Huang, Daniel P. Heruth, Chengpeng Bi, R Gaedigk, Xun Jiang, Ding-You Li, Gerald Wyckoff, Dmitry N. Grigoryev, Li Gao, Linheng Li, Min Wu, J Steven Leeder, Shui Qing Ye

Manuscripts, Articles, Book Chapters and Other Papers

Nicotinamide phosphoribosyltransferase (NAMPT) is a pleiotropic protein implicated in the pathogenesis of acute respiratory distress syndrome, aging, cancer, coronary heart diseases, diabetes, nonalcoholic fatty liver disease, obesity, rheumatoid arthritis, and sepsis. However, the underlying molecular mechanisms of NAMPT in these physiological and pathological processes are not fully understood. Here, we provide experimental evidence that a Nampt gene homozygous knockout (Nampt-/-) resulted in lethality at an early stage of mouse embryonic development and death within 5-10 days in adult mice accompanied by a 25.24±2.22% body weight loss, after the tamoxifen induction of NamptF/F × Cre mice. These results substantiate that Nampt …

Telomerase Reverse Transcriptase In Atherosclerosis, Hua Qing

Theses and Dissertations--Pharmacology and Nutritional Sciences

Telomerase reverse transcriptase (TERT) is the catalytic subunit of telomerase and the limiting factor for the enzyme activity. The expression of TERT and telomerase activity is increased in atherosclerotic plaques. However, the role of TERT dysregulation during atherosclerosis formation remains unknown.

The work herein first identified a multi-tiered regulation of TERT expression in smooth muscle cells (SMC) through histone deacetylase (HDAC) inhibition. HDAC inhibition induces TERT transcription and promoter activation. At the protein level in contrast, HDAC inhibition decreases TERT protein abundance through enhanced degradation, which decreases telomerase activity and induces senescence. Furthermore, during vascular remodeling in vivo, TERT protein …

Characterization Of The Role Of Insulin-Like Growth Factor Binding Protein 7 (Igfbp7) Using A Genetic Knockout Mouse Model, Maaged A. Akiel

Theses and Dissertations

In the US, the incidence and mortality rates of hepatocellular carcinoma (HCC) are alarmingly increasing since no effective therapy is available for the advanced disease. Activation of IGF signaling is a major oncogenic event in diverse cancers, including HCC. Insulin-like growth factor binding protein-7 (IGFBP7) inhibits IGF signaling by binding to IGF-1 receptor (IGF-1R) and functions as a potential tumor suppressor for hepatocellular carcinoma (HCC). IGFBP7 abrogates tumors by inducing cancer-specific senescence and apoptosis and inhibiting angiogenesis. We now document that Igfbp7 knockout (Igfbp7-/- ) mouse shows constitutive activation of IGF signaling, presents with pro-inflammatory and immunosuppressive microenvironment, and develops …

Immunodeficiency-Associated Lymphoid Hyperplasia As A Cause Of Intussusception In A Case Of Activated Pi3k-Δ Syndrome., Daniel Mettman, Isabelle Thiffault, Chitra Dinakar, Carol J. Saunders

Manuscripts, Articles, Book Chapters and Other Papers

Activated PI3K-δ syndrome refers to a recently described primary immunodeficiency syndrome consisting of recurrent sinopulmonary infections, lymphadenopathy, mucosal lymphoid aggregates, increased susceptibility to Epstein-Barr virus and cytomegalovirus, and increased incidence of B-cell lymphomas. Variants in PIK3CD, which encodes the phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit delta isoform, enhance membrane association and kinase activity, resulting in increased signal transduction through the PI3K-Akt pathway. Whole-exome sequencing revealed a pathogenic PIK3CD variant in a patient with history of immunologic impairment, recurrent sinopulmonary infections, and lymphoid hyperplasia presenting as intussusception. This case illustrates that while lymphoid hyperplasia secondary to immunodeficiency is most often unsurprising and …