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Proudfoot, J.

Publications and source records attributed to Proudfoot, J..

2 recordsLinked to original sources

A complex phenotypic assay of mammalian oocyte maturation identifies compounds that block meiotic progression for non-hormonal contraceptive discovery

Despite the prevalent use and efficacy of hormonal contraception, it remains unsuitable for many due to the prevalence of perceived and actual side effects. Thus, there is a need for novel contraceptives for women worldwide, especially non-hormonal options. During ovulation, oocytes undergo a maturation process by which they progress through meiosis, a specialized cell division needed to reduce chromosome content. Given that meiotic progression is essential for generating a fertilizable egg but does not affect hormone production, it represents a promising biological mechanism to target for female non-hormonal contraception. In this study, we developed a phenotypic screening platform modeled after biopharmaceutical industry practices using mouse oocytes to screen for compounds that block meiotic progression. Oocytes were matured in vitro in the presence of selected compounds from a bioactive compound library, and confirmed hits were identified as those that potently and reproducibly blocked meiotic progression. In addition, we showed that the inhibitory effect of these compounds was persistent and reversible. Thus, our oocyte drug screening pipeline provides a powerful system to identify novel drug discovery candidates for further follow up for non-hormonal contraception development.

cell biology↗

Noninvasive Vagus Nerve Stimulation Alters Neural Response and Physiological Autonomic Tone to Noxious Thermal Challenge

The mechanisms by which noninvasive vagal nerve stimulation (nVNS) affect central and peripheral neural circuits that subserve pain and autonomic physiology are not clear, and thus remain an area of intense investigation. Effects of nVNS vs sham stimulation on subject responses to five noxious thermal stimuli (applied to left lower extremity), were measured in 30 healthy subjects (n=15 sham and n=15 nVNS), with fMRI and physiological galvanic skin response (GSR). With repeated noxious thermal stimuli a group x time analysis showed a significantly (p < .001) decreased response with nVNS in bilateral primary and secondary somatosensory cortices (SI and SII), left dorsoposterior insular cortex, bilateral paracentral lobule, bilateral medial dorsal thalamus, right anterior cingulate cortex, and right orbitofrontal cortex. A group x time x GSR analysis showed a significantly decreased response in nVNS group (p < .0005) in bilaterally in SI, lower and mid medullary brainstem, and inferior occipital cortex. Finally, nVNS treatment showed decreased activity in pronociceptive brainstem nuclei (e.g. the reticular nucleus and rostral ventromedial medulla) and key autonomic integration nuclei (e.g. the rostroventrolateral medulla, nucleus ambiguous, and dorsal motor nucleus of the vagus nerve). In aggregate, noninvasive vagal nerve stimulation reduced the physiological response to noxious thermal stimuli and impacted neural circuits important for pain processing and autonomic output.

neuroscience↗