Betaine alleviates spermatogenic cells apoptosis of oligoasthenozoospermia rat model by up-regulating methyltransferases and affecting DNA methylation

Qiyan Lin; Xiyu Ge; Leilei Gao; Yanjun Chen; Ting Su; Menghua Ma; Huijun Wang; Cunwu Chen; Bangxing Han; Dong Liu

doi:10.1016/j.phymed.2024.155713

Betaine alleviates spermatogenic cells apoptosis of oligoasthenozoospermia rat model by up-regulating methyltransferases and affecting DNA methylation

Phytomedicine. 2024 May 6:129:155713. doi: 10.1016/j.phymed.2024.155713. Online ahead of print.

Authors

Qiyan Lin¹, Xiyu Ge¹, Leilei Gao¹, Yanjun Chen¹, Ting Su¹, Menghua Ma¹, Huijun Wang², Cunwu Chen¹, Bangxing Han³, Dong Liu⁴

Affiliations

¹ College of Biological and Pharmaceutical Engineering, West Anhui University, Generic Technology Research Center for Anhui Traditional Chinese Medicine Industry, Anhui Engineering Research Center for Eco-agriculture of Traditional Chinese Medicine, Lu'an, 237012, Anhui, China.
² Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China.
³ College of Biological and Pharmaceutical Engineering, West Anhui University, Generic Technology Research Center for Anhui Traditional Chinese Medicine Industry, Anhui Engineering Research Center for Eco-agriculture of Traditional Chinese Medicine, Lu'an, 237012, Anhui, China. Electronic address: hanbx1978@sina.com.
⁴ College of Biological and Pharmaceutical Engineering, West Anhui University, Generic Technology Research Center for Anhui Traditional Chinese Medicine Industry, Anhui Engineering Research Center for Eco-agriculture of Traditional Chinese Medicine, Lu'an, 237012, Anhui, China. Electronic address: liudong3000@126.com.

PMID: 38735196
DOI: 10.1016/j.phymed.2024.155713

Abstract

Background: Oligoasthenozoospermia is the most common type of semen abnormality in male infertile patients. Betaine (BET) has been proved to have pharmacological effects on improving semen quality. BET also belongs to endogenous physiological active substances in the testis. However, the physiological function of BET in rat testis and its pharmacological mechanism against oligoasthenozoospermia remain unclear.

Purpose: This research aims to prove the therapeutic effect and potential mechanism of BET on oligoasthenozoospermia rat model induced by Tripterygium wilfordii glycosides (TWGs).

Methods: The oligoasthenozoospermia rat model was established by a continuous gavage of TWGs (60 mg/kg) for 28 days. Negative control group, oligoasthenozoospermia group, positive drug group (levocarnitine, 300 mg/kg), and 200 mg/kg, 400 mg/kg, and 800 mg/kg BET groups were created for exploring the therapeutic effect of BET on the oligoasthenozoospermia rat model. The therapeutic effect was evaluated by HE and TUNEL staining. Immunofluorescence assay of DNMT3A, PIWIL1, PRMT5, SETDB1, BHMT2, and METTL3, methylation capture sequencing, Pi-RNA sequencing, and molecular docking were used to elucidate potential pharmacological mechanisms.

Results: It is proved that BET can significantly restore testicular pathological damage induced by TWGs, which also can significantly reverse the apoptosis of spermatogenic cells. The spermatogenic cell protein expression levels of DNMT3A, PIWIL1, PRMT5, SETDB1, BHMT2, and METTL3 significantly decreased in oligoasthenozoospermia group. 400 mg/kg and 800 mg/kg BET groups can significantly increase expression level of the above-mentioned proteins. Methylation capture sequencing showed that BET can significantly increase the 5mC methylation level of Spata, Spag, and Specc spermatogenesis-related genes. Pi-RNA sequencing proved that the above-mentioned genes produce a large number of Pi-RNA under BET intervention. Pi-RNA can form complexes with PIWI proteins to participate in DNA methylation of target genes. Molecular docking indicated that BET may not directly act as substrate for methyltransferase and instead participates in DNA methylation by promoting the methionine cycle and increasing S-adenosylmethionine synthesis.

Conclusion: BET has a significant therapeutic effect on oligoasthenozoospermia rat model induced by TWPs. The mechanism mainly involves that BET can increase the methylation level of Spata, Specc, and Spag target genes through the PIWI/Pi-RNA pathway and up-regulation of methyltransferases (including DNA methyltransferases and histone methyltransferases).

Keywords: Betaine; DNA methylation; Oligoasthenozoospermia; PIWI/Pi-RNA; Spermatogenic cell apoptosis.