ACTRT2 deficiency increases spermatogonia vulnerability to ferroptosis

Area of Science:

• Reproductive Biology
• Cell Biology
• Biochemistry

Background:

• Spermatogonia are crucial for male fertility but are susceptible to cell death, with unclear underlying mechanisms.
• Male infertility is a significant concern, often linked to impaired spermatogenesis and germ cell loss.

Purpose of the Study:

• To investigate the role of actin-related protein T2 (ACTRT2) in spermatogonia survival and its association with male infertility.
• To elucidate the mechanism by which ACTRT2 influences spermatogonial cell death, focusing on ferroptosis.

Main Methods:

• In vitro studies using spermatogonial cell lines treated with busulfan to assess cell death and reactive oxygen species (ROS) accumulation.
• In vivo studies involving ACTRT2 knockout (ACTRT2-/-) and heterozygous (ACTRT2+/-) mice, analyzing testicular morphology and spermatogenesis post-busulfan treatment.
• Analysis of gene and protein expression related to ferroptosis, lipid metabolism, and iron transport.

Main Results:

• Low ACTRT2 expression correlated with increased spermatogonial cell death, ROS accumulation, and ferroptosis indicators.
• ACTRT2-/- mice exhibited shrunken seminiferous tubules, while ACTRT2+/- mice showed reduced spermatogenesis after busulfan exposure.
• Busulfan-induced damage in ACTRT2+/- testes involved upregulation of ferroptosis markers (ACSL4, ALOX15) and downregulation of protective factors (SLC7A11, GPX4).
• Deficiency in ACTRT2 led to increased expression of iron uptake genes (SLC11A2, IREB2, TFRC), resulting in intracellular iron overload and mitochondrial damage.

Conclusions:

• ACTRT2 plays a critical role in protecting spermatogonia from ferroptosis.
• ACTRT2 deficiency compromises male fertility by inducing iron overload and mitochondrial dysfunction, making spermatogonia vulnerable to ferroptosis.
• Targeting ACTRT2 or related pathways may offer therapeutic strategies for male infertility associated with ferroptosis.