Undergraduate Honors Theses

Thesis Defended

Spring 2019

Document Type

Thesis

Type of Thesis

Departmental Honors

Department

Integrative Physiology

First Advisor

Christopher Link

Second Advisor

Mark Opp

Third Advisor

Ricardo Stephen

Abstract

Cryoprotectant toxicity (CT), or the injury due to cryoprotectant (CPA) exposure, remains the most limiting barrier to performing successful organ cryopreservation. An intervention alleviating the stress induced by CT in mouse embryonic stem cell (mESC) models may translate well into tissue and organ models of cryopreservation. Such discoveries could enable large-scale organ banking and, potentially, end the transplantable-organ shortage. In this study, I sought to see if CT could be combated through a hormetic approach. Hormesis will be defined as the negation of the detrimental effects of a high, lethal dosage of a stressor via a prior nonlethal dosage of the same stressor with a recovery period in between each exposure. Wild-type mESCs were exposed to a pretreatment of 0%, 1% or 2% CPA (M22 in these studies) in embryonic stem cell medium (ESCM), allowed to recover, and subsequently exposed to a lethal dosage of 9% M22 in ESCM. Pretreatments of 1% and 2% M22 in ESCM resulted in greater loss of viability as compared to no previous exposure to M22. This study failed to induce a hormetic effect in mESCs, however, hormesis remains a plausible mechanistic approach to the alleviation of CT due to CPA exposure. More research exploring a broader selection of M22 pretreatment conditions and recovery periods need to be observed using experimental protocols similar to those outlined in this paper.

Share

COinS