Dynamic Assessment of Functional Lipidomic Analysis in Human Urine

The development of enabling mass spectrometry platforms for the quantification of diverse lipid species in human urine is of paramount importance for understanding metabolic homeostasis in normal and pathophysiological conditions. Urine represents a non‐invasive biofluid that can capture distinct differences in an individual's physiological status. However, currently there is a lack of quantitative workflows to engage in high throughput lipidomic analysis. This study describes the development of a MS/MS^ALL shotgun lipidomic workflow and a micro liquid chromatography–high resolution tandem mass spectrometry (LC–MS/MS) workflow for urine structural and mediator lipid analysis, respectively. This workflow was deployed to understand biofluid sample handling and collection, extraction efficiency, and natural human variation over time. Utilization of 0.5 mL of urine for structural lipidomic analysis resulted in reproducible quantification of more than 600 lipid molecular species from over 20 lipid classes. Analysis of 1 mL of urine routinely quantified in excess of 55 mediator lipid metabolites comprised of octadecanoids, eicosanoids, and docosanoids generated by lipoxygenase, cyclooxygenase, and cytochrome P450 activities. In summary, the high‐throughput functional lipidomics workflow described in this study demonstrates an impressive robustness and reproducibility that can be utilized for population health and precision medicine applications.     

Diabetes-induced protection from cisplatin nephrotoxicity is associated with impairment of energy-dependent uptake by renal cortex slices

Ritual scarification is the culturally sanctioned process of incising the skin to achieve patterned scars. Scarification was practiced widely by traditional societies, but the encroachment of Western cultural expectations has made the practice increasingly uncommon. Ritual tattooing has a meaningful place in many traditional societies. Ritual scarification and tattooing are still found on Santa Catalina Island, an isolated member of the Solomon Islands in the south-west Pacific.     

Adapted MS/MSALL Shotgun Lipidomics Approach for Analysis of Cardiolipin Molecular Species

Cardiolipin (Ptd₂Gro) is a complex, doubly charged phospholipid located in the inner mitochondrial membrane where it plays an essential role in regulating bioenergetics. Abnormalities in Ptd₂Gro content or composition have been associated with mitochondrial dysfunction in a variety of disease states. Here, we report the development of an adapted high‐resolution data‐independent acquisition (DIA) MS/MS^ALL shotgun lipidomic method to enhance the accuracy and reproducibility of Ptd₂Gro molecular species quantitation from biological samples. Utilizing the doubly charged molecular ions and the isotopic pattern with negative mode electrospray ionization mass spectrometry (ESI‐MS) using an adapted MS/MS^ALL approach, we profiled more than 150 individual Ptd₂Gro species, including monolysocardiolipin (MLPtd₂Gro). The method described in this study demonstrated high reproducibility, sensitivity, and throughput with a wide dynamic range. This high‐resolution MS/MS^ALL shotgun lipidomics approach could be extended to screening aberrations of Ptd₂Gro metabolism involved in mitochondrial dysfunction in various pathological conditions and diseases.