Automation of On-Resin Enrichment of S-Nitrosylated Proteins for Oxidized Cysteine-Selective cPILOT.

S-Nitrosylation (SNO) is a cysteine post-translational modification that increases with normal aging and is present in Alzheimer's disease and other aging-related illnesses. Detection of SNO-modified proteins can be challenging; however, we previously developed a robust quantitative proteomics approach termed "Oxidized Cysteine-Selective combined precursor isobaric labeling and isobaric tagging (OxcyscPILOT)" that allows for detection of endogenous SNO-modified proteins. OxcyscPILOT involves enrichment of SNO-modified proteins using a thiol-based resin.

Quantitative proteomics to study aging in rabbit liver.

Aging globally effects cellular and organismal metabolism across a range of mammalian species, including humans and rabbits. Rabbits (Oryctolagus cuniculus are an attractive model system of aging due to their genetic similarity with humans and their short lifespans. This model can be used to understand metabolic changes in aging especially in major organs such as liver where we detected pronounced variations in fat metabolism, mitochondrial dysfunction, and protein degradation.

The roles of S-nitrosylation and S-glutathionylation in Alzheimer's disease.

Alzheimer's disease (AD) is a debilitating dementia with complex pathophysiological alterations including modifications to endogenous cysteine. S-nitrosylation (SNO) is a well-studied posttranslational modification (PTM) in the context of AD while S-glutathionylation (PSSG) remains less studied. Excess reactive oxygen and reactive nitrogen species (ROS/RNS) directly or indirectly generate SNO and PSSG.

3D-templated, fully automated microfluidic input/output multiplexer for endocrine tissue culture and secretion sampling.

A fully automated, 16-channel microfluidic input/output multiplexer (μMUX) has been developed for interfacing to primary cells and to improve understanding of the dynamics of endocrine tissue function. The device utilizes pressure driven push-up valves for precise manipulation of nutrient input and hormone output dynamics, allowing time resolved interrogation of the cells. The ability to alternate any of the 16 channels from input to output, and vice versa, provides for high experimental flexibility without the need to alter microchannel designs.

Macro-to-micro interfacing to microfluidic channels using 3D-printed templates: application to time-resolved secretion sampling of endocrine tissue.

Employing 3D-printed templates for macro-to-micro interfacing, a passively operated polydimethysiloxane (PDMS) microfluidic device was designed for time-resolved secretion sampling from primary murine islets and epidiymal white adipose tissue explants. Interfacing in similar devices is typically accomplished through manually punched or drilled fluidic reservoirs. We previously introduced the concept of using hand fabricated polymer inserts to template cell culture and sampling reservoirs into PDMS devices, allowing rapid stimulation and sampling of endocrine tissue.