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Zuckerman, A. L.

Publications and source records attributed to Zuckerman, A. L..

2 recordsLinked to original sources

Rapid, high-resolution, non-destructive assessments of metabolic and morphological homogeneity uniquely identify high-grade cervical precancerous lesions

PurposeTwo-photon microscopy (2PM) is an emerging clinical imaging modality with the potential to non-invasively assess tissue metabolism and morphology in high-resolution. This study aimed to assess the translational potential of 2PM for improved detection of high-grade cervical precancerous lesions. Experimental Design2P images attributed to reduced nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and oxidized flavoproteins (FP) were acquired from the full epithelial thickness of freshly excised human cervical tissue biopsies (N = 62). Fifteen biopsies harbored high-grade squamous intraepithelial lesions (HSILs), 14 biopsies harbored low-grade SILs (LSILs), and 33 biopsies were benign. Quadratic discriminant analysis (QDA) leveraged morphological and metabolic functional metrics extracted from these images to predict the presence of HSILs. We performed gene set enrichment analysis (GSEA) using datasets available on the Gene Expression Omnibus (GEO) to validate the presence of metabolic reprogramming in HSILs. ResultsIntegrating metabolic and morphological 2P-derived metrics from finely sampled, full-thickness epithelia achieved a high 90.8 {+/-} 6.1% sensitivity and 72.3 {+/-} 11.3% specificity of HSIL detection. Notably, sensitivity (91.4 {+/-} 12.0%) and specificity (77.5 {+/-} 12.6%) were maintained when utilizing metrics from only two images at 12- and 72-{micro}m from the tissue surface. Upregulation of glycolysis, fatty acid metabolism, and oxidative phosphorylation in HSIL tissues validated the metabolic reprogramming captured by 2P biomarkers. ConclusionLabel-free 2P images from as few as two epithelial depths enable rapid and robust HSIL detection through the quantitative characterization of metabolic and morphological reprogramming, underscoring the potential of this tool for clinical evaluation of cervical precancers. Translational Relevance StatementThe colposcopy and biopsy paradigm for cervical pre-cancer detection leads to an excessive number of unnecessary biopsies, with significant economic and psychological costs. This study highlights the potential of label-free, high-resolution two photon imaging to improve this paradigm by introducing real-time morphofunctional tissue assessments. In an extensive dataset comprising freshly excised high-grade and low-grade cervical intraepithelial lesions, along with benign metaplastic and inflamed human cervical tissue biopsies, we successfully characterize a loss of morphofunctional heterogeneity indicative of high-grade precancerous changes. Leveraging a combination of two-photon imaging-derived quantitative morphofunctional metrics, our findings showcase a substantial improvement in both sensitivity and specificity of high-grade lesion detection compared to the current gold standard of colposcopy followed by a single biopsy. The demonstrated enhancement in sensitivity and specificity highlights the prospect of integrating non-invasive, label-free metabolic imaging into clinical practice, offering a more effective and efficient approach to identify and manage cervical precancerous lesions.

bioengineering↗

A genetically encoded tool to increase cellular NADH/NAD+ ratio in living cells

Impaired reduction/oxidation (redox) metabolism is a key contributor to the etiology of many diseases, including primary mitochondrial disorders, cancer, neurodegeneration, and aging. However, mechanistic studies of redox imbalance remain challenging due to limited strategies which can perturb cellular redox metabolism and model pathology in various cellular, tissue, or organismal backgrounds without creating additional and potentially confounding metabolic perturbations. To date, most studies involving impaired redox metabolism have focused on oxidative stress and reactive oxygen species (ROS) production; consequently, less is known about the settings where there is an overabundance of reducing equivalents, termed reductive stress. NADH reductive stress has been modeled using pharmacologic inhibition of the electron transport chain (ETC) and ethanol supplementation. Still, both these methods have significant drawbacks. Here, we introduce a soluble transhydrogenase from E. coli (EcSTH) as a novel genetically encoded tool to promote NADH overproduction in living cells. When expressed in mammalian cells, EcSTH, and a mitochondrially-targeted version (mitoEcSTH), can elevate the NADH/NAD+ ratio in a compartment-specific manner. Using this tool, we determine the metabolic and transcriptomic signatures of NADH reductive stress in mammalian cells. We also find that cellular responses to NADH reductive stress, including blunted proliferation, are dependent on cellular background and identify the metabolic reactions that sense changes in the cellular NADH/NAD+ balance. Collectively, our novel genetically encoded tool represents an orthogonal strategy to perturb redox metabolism and characterize the impact on normal physiology and disease states.

bioengineering↗