Regulation of Stem Spermatogonia in the Mature Testis

Investigative trial to evaluate the role of a glial cell lined derived neurotrophic factor (GDNF) in regulation of spermatogonial renewal and testicular function. Goal of the trial is to provide greater information on the mechanisms that effect stem spermatogonial maintenance renewal and proliferation in its relation to male infertility.

Study Overview

Status

Completed

Conditions

Detailed Description

An essential requirement for sustaining male fertility is maintaining an adequate number of stem spermatogonia, the foundation of spermatogenesis. To achieve this, when the stem cells divide, some progeny must remain stem spermatogonia while other progeny differentiate. It is obvious that the correct balance between self-renewing replication and differentiation of stem spermatogonia is crucial to male fertility, and there is a indirect evidence that GDNF plays an important role in maintaining this balance in the normal mature testis. However, almost nothing is known about the in vivo regulation of this balance in the mature organ, of the specific function of GDNF in the adult testis, or if physiological changes in GDNF expression significantly affect the replication or differentiation of the stem cells. To address these critical issues, a unique mouse model that allows GDNF signaling to the stem spermatogonia to be specifically and reversibly inhibited in vivo by an ATP antagonist. With this model, the first direct evidence that GDNF is required for maintaining the stem spermatogonial pool in a normal mature testis. Additionally, the investigators have shown that when inhibition of GDNF signaling is reversed, the stem cells begin to rebuild the stem cell pool. Importantly, our data demonstrate that some stem spermatogonia are lost when GDNF signaling is inhibited for as little as 2 days, while other stem cells survive for up to 11 days. This suggests that factors intrinsic or extrinsic to the stem cells modulate the response to GDNF. Using this new mouse model the mechanisms responsible for the loss of stem spermatogonia proliferation and regeneration will be investigated along with GDNF signaling and inhibition. At the end of all of this these studies will be done on waste tissue obtained from normal men and men with infertility who otherwise have testicular surgery for therapeutic purposes.

Study Type

Observational

Enrollment (Actual)

142

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

    • New York
      • New York, New York, United States, 10065
        • Weill Cornell Medicine

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 75 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

Male

Sampling Method

Non-Probability Sample

Study Population

Healthy males undergoing testicular biopsy by any urologic surgeon at Weill Cornell Medicine.

Description

Inclusion Criteria:

  • undergoing testicular biopsy at Weill Cornell Medicine/New York Presbyterian

Exclusion Criteria:

  • females and any males outside of the age parameter of 18-75 years old

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Levels of glial cell line derived neurotrophic factor (GDNF) in normal testis compared to abnormal testicular tissue obtained from infertile patients
Time Frame: five years
Levels of glial cell line derived neurotrophic factor (GDNF) in normal testis compared to abnormal testicular tissue.
five years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

April 1, 2012

Primary Completion (Actual)

November 7, 2019

Study Completion (Actual)

December 5, 2019

Study Registration Dates

First Submitted

April 13, 2016

First Submitted That Met QC Criteria

April 27, 2016

First Posted (Estimate)

April 29, 2016

Study Record Updates

Last Update Posted (Actual)

March 24, 2023

Last Update Submitted That Met QC Criteria

March 23, 2023

Last Verified

March 1, 2023

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 1202012193
  • 1P50HD096723-01A1 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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