Identification of Two Novel Mutations in KDM3A Regulatory Gene in Iranian Infertile Males

Spermatozoa retrieval in azoospermia and expression profile of JMJD1A, TNP2, and PRM2 in a subset of the Karachi population

BACKGROUND

The difficulties encountered in surgical spermatozoa retrieval for intracytoplasmic sperm injection procedure in azoospermic men have stressed the dire need for a robust biomarker for the prediction of spermatozoa retrieval. Data have highlighted the role of JMJD1A (Jumonji domain-containing 1A), a histone H3K9 demethylase, and other nuclear proteins, protamines (PRM) and transition nuclear proteins (TNP), as biomarkers in male infertility.

OBJECTIVE

To access successful spermatozoa retrieval at the time of intracytoplasmic sperm injection by evaluating the mRNA expression profile of JMJD1A, TNP, and PRM in testicular tissue.

MATERIALS/METHODS

About 100 azoospermic patients, who visited the Australian Concept Infertility Medical Center, Karachi for spermatozoa retrieval by testicular sperm extraction or microsurgical testicular sperm extraction participated in the study. mRNA expression of the JMJD1A, TNP1, TNP2, PRM1, and PRM2 genes was determined. Patients were categorized into successful spermatozoa retrieval (n = 42) group and unsuccessful spermatozoa retrieval (n = 58) group.

RESULTS

Azoospermic men in successful spermatozoa retrieval had significantly increased expression of JMJD1A, TNP2, and PRM2. The hormonal parameters - follicle-stimulating hormone, luteinizing hormone, and thyroid-stimulating hormone were significantly higher in unsuccessful spermatozoa retrieval. Multivariate analysis showed a significant association between JMJD1A, TNP2, PRM2, and successful spermatozoa retrieval. The area under the receiver operating characteristics curve showed a significant discriminatory ability to predict the spermatozoa retrieval outcome in azoospermic patients for mRNA expression of JMJD1A, TNP2, and PRM2 was 71, 72, and 73%, respectively. The area under the curve for follicle-stimulating hormone, luteinizing hormone, and thyroid-stimulating hormone was 0.67, 0.81, and 0.65, respectively.

DISCUSSION

Our study demonstrates that the mRNA expression profile of JMJD1A, TNP2, and PRM2 along with hormonal parameters, is a useful marker to assess the probability of spermatozoa retrieval before intracytoplasmic sperm injection intervention.

CONCLUSION

The probability of spermatozoa retrieval in azoospermic patients is increased when the mRNA expression profile of JMJD1A, TNP2, and PRM2 in testicular tissue is increased.

Roles of HIF and 2-Oxoglutarate-Dependent Dioxygenases in Controlling Gene Expression in Hypoxia

Simple Summary

Hypoxia—reduction in oxygen availability—plays key roles in both physiological and pathological processes. Given the importance of oxygen for cell and organism viability, mechanisms to sense and respond to hypoxia are in place. A variety of enzymes utilise molecular oxygen, but of particular importance to oxygen sensing are the 2-oxoglutarate (2-OG) dependent dioxygenases (2-OGDs). Of these, Prolyl-hydroxylases have long been recognised to control the levels and function of Hypoxia Inducible Factor (HIF), a master transcriptional regulator in hypoxia, via their hydroxylase activity. However, recent studies are revealing that such dioxygenases are involved in almost all aspects of gene regulation, including chromatin organisation, transcription and translation.

Abstract

Hypoxia—reduction in oxygen availability—plays key roles in both physiological and pathological processes. Given the importance of oxygen for cell and organism viability, mechanisms to sense and respond to hypoxia are in place. A variety of enzymes utilise molecular oxygen, but of particular importance to oxygen sensing are the 2-oxoglutarate (2-OG) dependent dioxygenases (2-OGDs). Of these, Prolyl-hydroxylases have long been recognised to control the levels and function of Hypoxia Inducible Factor (HIF), a master transcriptional regulator in hypoxia, via their hydroxylase activity. However, recent studies are revealing that dioxygenases are involved in almost all aspects of gene regulation, including chromatin organisation, transcription and translation. We highlight the relevance of HIF and 2-OGDs in the control of gene expression in response to hypoxia and their relevance to human biology and health.