To explore the effect and mechanism of“Zhibian（BL54）-to-Shuidao（ST28）”acupuncture on improving the reproductive function of poor ovarian response（POR）mice by regulating ovarian mitochondrial dysfunction.

The screened mice with regular estrous cycles were randomly divided into a blank group，a model group and an acupuncture group. The mice in the model and acupuncture groups were administered Tripterygium wilfordii polysaccharide suspension（50 mg·kg^-1·d^-1）by gavage for 2 weeks，while the blank group received an equivalent volume of 0.9% sodium chloride solution by gavage. After modeling，the mice in the acupuncture group received continuous acupuncture treatment using“Zhibian（BL 54）-to-Shuidao（ST 28）”acupuncture for 2 weeks，once a day，20 minutes for each time. Then the three groups simultaneously underwent ovulation induction，and the samples were collected on the next day. Vaginal smears were used to observe the changes in the estrous cycle of mice. The number of retrieved oocytes，ovarian wet weight and ovarian index were measured. The serum levels of anti-Müllerian hormone（AMH），follicle-stimulating hormone（FSH），estradiol（E2）and luteinizing hormone（LH）were detected using enzyme-linked immunosorbent assay（ELISA）. The histopathological and ultrastructural changes in the ovary were observed through hematoxylin-eosin（HE）staining and transmission electron microscopy. The fluorescence staining was employed to detect the changes in mitochondrial membrane permeability pore（MPTP）permeability in ovarian tissues. The real-time fluorescent quantitative PCR was used to assess the mRNA expression levels of nuclear respiratory factor 1（NRF1），peroxisome proliferator-activated receptor-γcoactivator-1α（PGC-1α）and mitochondrial transcription factor A（TFAM）in ovarian tissues. The terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling（TUNEL）staining was conducted to determine the apoptotic rate of positive cells in ovarian tissues and Western blot analysis was utilized to quantify the relative protein expressions of B-cell lymphoma-2（BCL-2），BCL-2-associated X protein（BAX），cytochrome C（Cyt C），cysteine-aspartic acid protease（Caspase）-9 and Caspase-3 in ovarian tissues.

Compared with the blank control group，the model group showed a significantly increased rate of estrous cycle disorder（P<0.01）. The number of ovulations，ovarian wet weight and ovarian index decreased significantly（P<0.01）. The serum levels of FSH and LH increased（P<0.01），while the levels of AMH and E2 decreased（P<0.01）. The pathological morphology of ovarian tissues and internal mitochondrial structure deteriorated. Mitochondrial membrane permeability increased（P<0.01）. The mRNA expression levels of PGC-1α，NRF1 and TFAM decreased to varying degrees（P<0.01，P<0.05）. The apoptotic rate of positive cells increased（P<0.01）. The protein expression levels of BAX，Cyt C，Caspase-9 and Caspase-3 increased（P<0.01，P<0.05），while the protein expression level of BCL-2 decreased（P<0.01）. Compared with the model group，the acupuncture group exhibited a significantly reduced rate of estrous cycle disorder（P<0.01）. The number of ovulations，ovarian wet weight and ovarian index increased significantly（P<0.01）. The serum levels of FSH and LH decreased（P<0.01），while the levels of AMH and E2 increased（P<0.01）. The pathological morphology of ovarian tissues and internal mitochondrial structure improved. Mitochondrial membrane permeability decreased（P<0.01）. The mRNA expression levels of PGC-1α，NRF1 and TFAM increased（P<0.01，P<0.05）. The apoptotic rate of positive cells decreased（P<0.01）. The protein expression levels of BAX，Cyt C，Caspase-9 and Caspase-3 decreased（P<0.01，P<0.05），while the protein expression level of BCL-2 increased（P<0.01）.

The“Zhibian（BL54）-to-Shuidao（ST28）”acupuncture may improve the mitochondrial dysfunction in the ovaries of POR mice by regulating the key factors involved in mitochondrial biogenesis and the mitochondrial apoptosis pathway，thereby reducing granulosa cell apoptosis in the ovary and enhancing ovarian responsiveness.