Effect of RNA Later on RNA Integrity in The Snap Freezing of Testis Tissues

Background: Human tissues biobanking encompasses a widerange of activities and study designs and also has a critical rolefor application of new technologies to the discovery of molecularpatterns of disease and novel biomarkers into clinical trials.Testis tissue plays a dominant role in diagnostic and treatmentazoospermia patients.The purpose of this study was to assessthe impact of freezing on RNA integrity in tissue specimensand also comparison between immersion in liquid nitrogen (unfixed)and immersed (fixed) in a commercial RNA-stabilizingbuffer (RNAlater).Materials and Methods: In this study, ۳۰ samples of infertilemen with azoospermia were evaluated. Collecting the sampleswas performed during the surgical resection at Royan InfertilityClinic. Following that, the ۱۵ tissues were freezed directly byimmersion in liquid nitrogen (-۱۹۶°C) and the ۱۵ testis sampleswere preserved in RNA later and stored in -۸۰ (fixed). RNAintegrity was analyzed by agarose gel electrophoresis. In addition,the RNA integrity number (RIN) was measured by theAgilent ۲۱۰۰ Bioanalyzer.Results: The portion of ۲۸S/۱۸S in fixed samples was dramaticallyhigher than in unfixed samples. In unfixed samples degradationof RNA increased. In addition RIN in unfixed samplessignificantly decreased than in fixed samples.Conclusion: Our study shows that the immersion of the tissuesin RNAlater efficiently prevented RNA degradation. Thus, degradationof RNA in unfixed samples occurs. Already decrease inRNA quality may result in significantly decrease in RIN valuesin testis tissue samples. According to the RIN results, we recommendthat the preservation of testis tissues with RNAlateris better than frozen without RNAlater for studies requiringRNA of high quality. Our study shows that the immersion ofthe tissues in RNAlater efficiently prevented RNA degradation.Thus, degradation of RNA in unfixed samples occurs. Alreadydecrease in RNA quality may result in significantly decrease inRIN values in testis tissue samples. According to the RIN results,we recommend that the preservation of testis tissues withRNAlater is better than frozen without RNAlater for studies requiringRNA of high quality. Our study shows that the immersionof the tissues in RNAlater efficiently prevented RNA degradation.Thus, degradation of RNA in unfixed samples occurs.Already decrease in RNA quality may result in significantlydecrease in RIN values in testis tissue samples. According tothe RIN results, we recommend that the preservation of testistissues with RNAlater is better than frozen without RNAlaterfor studies requiring RNA of high quality. Our study showsthat the immersion of the tissues in RNAlater efficiently preventedRNA degradation. Thus, degradation of RNA in unfixedsamples occurs. Already decrease in RNA quality may resultin significantly decrease in RIN values in testis tissue samples.According to the RIN results, we recommend that the preservationof testis tissues with RNAlater is better than frozen withoutRNAlater for studies requiring RNA of high quality.

کلیدواژه ها:

Testis Tissue ، RNA Integrity Number ، RNAlater