[Efficacy of Yu Si Granules on methyl methanesulphonate-induced oligoasthenozoospermia in mice].

OBJECTIVE: To investigate the effect and action mechanism of Yu Si Granules (YSG) in the treatment methyl methanesulphonate (MMS)-induced oligoasthenozoospermia (OAZ) in mice. METHODS: Thirty adult male mice were randomly divided into three groups of equal number, normal control, OAZ model control and YSG intervention. The OAZ model was established by oral administration of MMS and the model mice in the YSG intervention group were treated intragastrically with YSG suspension at 0.144 g/100 g of the body weight per day for 48 successive days. Then, all the mice were sacrificed and their epididymides harvested for detection of the sperm count and motility, observation of the morphology of the seminiferous tubules by HE staining, determination of the expressions of the germ cell-, sperm cell-, spermatocyte-, Sertoli cell- and blood-testis barrier-related genes by RT-PCR, and measurement of the levels of oxidative stress in the blood. RESULTS: Compared with the normal control, the OAZ model mice showed significantly decreased sperm count (ï¼»49.2 ± 0.7ï¼½ vs ï¼»23.6 ± 0.4ï¼½ ×107/ml/g, P < 0.05) and sperm motility (ï¼»76.3 ± 0.7ï¼½% vs ï¼»5.0 ± 5.8ï¼½%, P < 0.05), which were both remarkably increased after YSG intervention (ï¼»38.4 ± 0.5ï¼½ ×107/ml/g and ï¼»71.5 ± 0.5ï¼½%) (P < 0.05). The OAZ model mice also exhibited degenerated and atrophic seminiferous tubules, thinner seminiferous epithelia, disorderly arranged cells at different levels, reduced number of sperm in the lumen and unclear layers of germ cells in the epididymis, while those after YSG intervention manifested regularly organized seminiferous tubules with orderly arrangement and clear layers. The expressions of the Vasa, Dazl and Snd1 genes were significantly decreased (P < 0.05), but not those of Gfra, Plzf, Stra8, Spo11, Sycp3, Sox9 and Vim (P > 0.05) in the OAZ model and YSG intervention groups as compared with those in the normal control group. The superoxide dismutase (SOD) activity in the serum was markedly reduced in the OAZ model mice as compared with that in the normal controls (P < 0.05) and increased again after YSP intervention (P < 0.05), but the opposite was the case with the expression of the superoxide anion. CONCLUSIONS: YSG can significantly reduce MMS-induced OAZ in mice, which may be associated with oxidative stress.

[Male reproductive toxicity of bisphenol A].

The reproductive toxicity of environmental endocrine disruptors has attracted substantial attention from researchers in recent years. Bisphenol A (BPA) is among the most prominent environmental estrogens worldwide, demonstrated to be related with the impairment of male reproductive function as well as other health problems, such as diabetes, obesity, cardiovascular diseases, and cancer. BPA acts primarily by mimicking antiandrogenic and estrogenic effects, disturbing the hypothalamic-pituitary-testicular axis and modulating gene expressions and enzyme activities in the hormone biosynthesis affecting steroids or its receptors. BPA is also involved in DNA methylation and the effects of epigenetics, resulting in dyszoospermia, oligoasthenoteratospermia/azoospermia and/or infertility in males. This review addresses the effects of BPA on male reproductive function, focusing on the mechanisms of its toxicity on spermatogenesis, semen quality, and the reproductive system.

Youjing granules ameliorate spermatogenesis in rats through regulating the prolifereation of spermatogonial stem cells.

Male infertility has evolved from a common reproductive system disease to a major social issue. Youjing granule (YG) is a Chinese medicinal material used as a therapy method for tonifying the kidneys and removing dampness due to its pathogenic characteristics. YG has been shown to regulate sperm quality in clinical trials, but the underlying mechanism is not fully understood. The present study was aimed to explore the protective effects and mechanism of action of YG on male reproductive system damage caused by methyl methane sulfonate (MMS). We first established an infertility model of rats through oral administration of MMS and then treated with YG. To determine the effect of YG, spermatogenesis, microvascular density, and secretory function of Leydig cells and Sertoli cells in rats were assessed. Spermatogonial stem cells (SSCs) were co-cultured with mouse embryo fibroblast (MEF) cells as an in vitro cell model before exposure to serum containing YG. Furthermore, the proliferation and apoptosis of SSCs were measured. Results indicated that YG increased the expression of self-renewal and proliferation-related molecules such as glial cell line derived neurotrophic factor (GDNF) and fibroblast growth factor-2 (FGF2), and improved the quality of sperm and the proliferation of SSCs. In conclusion, YG may protect spermatogenetic function of rats through regulating the proliferation and self-renewal of SSCs.

Mutation Screening and Functional Study of SLC26A4 in Chinese Patients with Congenital Hypothyroidism

Objective: Defects in the human solute carrier family 26 member 4 (SLC26A4) gene are reported to be one of the causes of congenital hypothyroidism (CH). We aimed to identify SLC26A4 mutations in Chinese patients with CH and analyze the function of the mutations. Methods: Patients with primary CH were screened for 21 CH candidate genes mutations by targeted next-generation sequencing. All the exons and exon-intron boundaries of SLC26A4 were identified and analyzed. The function of six missense mutation in SLC26A4 were further investigated in vitro. Results: Among 273 patients with CH, seven distinct SLC26A4 heterozygous mutations (p.S49R, p.I363L, p.R409H, p.T485M, p.D661E, p.H723R, c.919-2A>G) were identified in 10 patients (3.66%, 10/273). In vitro experiments showed that mutation p.I363L, p.R409H, p.H723R affect the membrane location and ion transport of SLC26A4, while p.S49R did not. Mutation p.T485M and p.D661E only affected ion transport, but had no effect on the membrane location. Conclusion: The prevalence of SLC26A4 mutations was 3.66% in Chinese patients with CH. Five mutations (p.I363L, p.R409H, p.T485M, p.D661E and p.H723R) impaired the membrane location or ion transport function of SLC26A4, suggesting important roles for Ile363, Arg409, Thr485, Asp661, and His723 residues in SLC26A4 function. As all variants identified were heterozygous, the pathogenesis of these patients cannot be explained, and the pathogenesis of these patients needs further study.

Genetic Analysis of 25 Patients with 5α-Reductase Deficiency in Chinese Population.

BACKGROUND: A deficiency in steroid 5α-reductase type 2 is an autosomal recessive disorder. Affected individuals manifested ambiguous genitalia, which is caused by decreased dihydrotestosterone (DHT) synthesis in the fetus. METHODS: We analyzed 25 patients with 5α-reductase deficiency in China. Seventeen of the 25 patients (68%) were initially raised as females. Sixteen patients changed their social gender from female to male after puberty. RESULTS: Eighteen mutations were identified in these patients. p.Gly203Ser and p.Gln6∗ were found to be the most prevalent mutations. On the basis of the genotype of these patients, we divided them into different groups. There was no significant difference in hormone levels and external masculinization score (EMS) in patients with or without these prevalent mutations. Twelve common single-nucleotide polymorphisms (SNPs) near the p.Gln6∗ mutation were chosen for haplotype analysis. Three haplotypes were observed in 6 patients who had the p.Gln6∗ mutation (12 alleles). CONCLUSION: We analyzed mutations of the SRD5A2 gene in Chinese patients with 5α-reductase deficiency. Although hotspot mutations exist, no founder effect of prevalent mutations in the SRD5A2 gene was detected in the Chinese population.

Identification of three novel SRD5A2 mutations in Chinese patients with 5α-reductase 2 deficiency.

In this study, we investigated the genetics, clinical features, and therapeutic approach of 14 patients with 5α-reductase deficiency in China. Genotyping analysis was performed by direct sequencing of PCR products of the steroid 5α-reductase type 2 gene (SRD5A2). The 5α-reductase activities of three novel mutations were investigated by mutagenesis and an in vitro transfection assay. Most patients presented with a microphallus, variable degrees of hypospadias, and cryptorchidism. Eight of 14 patients (57.1%) were initially reared as females and changed their social gender from female to male after puberty. Nine mutations were identified in the 14 patients. p.G203S, p.Q6X, and p.R227Q were the most prevalent mutations. Three mutations (p.K35N, p.H162P, and p.Y136X) have not been reported previously. The nonsense mutation p.Y136X abolished enzymatic activity, whereas p.K35N and p.H162P retained partial enzymatic activity. Topical administration of dihydrotestosterone during infancy or early childhood combined with hypospadia repair surgery had good therapeutic results. In conclusion, we expand the mutation profile of SRD5A2 in the Chinese population. A rational clinical approach to this disorder requires early and accurate diagnosis, especially genetic diagnosis.

Energy transfer model and its applications of ultrasonic gas flow-meter under static and dynamic flow rates.

Most of the ultrasonic gas flow-meters measure the gas flow rate by calculating the ultrasonic transmission time difference between the downstream and upstream. Ultrasonic energy attenuation occurs in the processes of the ultrasonic generation, conversion, transmission, and reception. Additionally, at the same time, the gas flow will also affect the ultrasonic propagation during the measurement, which results in the ultrasonic energy attenuation and the offset of ultrasonic propagation path. Thus, the ultrasonic energy received by the transducer is weaker. When the gas flow rate increases, this effect becomes more apparent. It leads to the measurement accuracy reduced, and the measurement range narrowed. An energy transfer model, where the ultrasonic gas flow-meter under without/with the gas flow, is established by adopting the statistical analysis and curve fitting based on a large amount of experimental data. The static sub model without the gas flow expresses the energy conversion efficiency of ultrasonic gas transducers, and the dynamic sub model with the gas flow reflects the energy attenuation pattern following the flow rate variations. The mathematical model can be used to determine the minimum energy of the excitation signal for meeting the requirement of specific measurement range, and predict the maximum measurable flow rate in the case of fixed energy of excitation signal. Based on the above studies, a method to enhance the excitation signal energy is proposed under the output power of the transmitting circuit being a finite value so as to extend the measurement rage of ultrasonic gas flow-meter.

Aromatase deficiency: a novel compound heterozygous mutation identified in a Chinese girl with severe phenotype and obvious maternal virilization.

BACKGROUND: Aromatase deficiency is a rare autosomal recessive disorder that is caused by an impairment of androgen conversion to estrogens. Affected 46, XX individuals generally present with virilization of external genitalia at birth and mutations in CYP19A1 gene. OBJECTIVE: This study described the clinical features and molecular basis of a Chinese 46, XX girl born with ambiguous genitalia and investigated the functional alteration of two novel mutations of the CYP19A1 gene. METHODS AND RESULTS: Obvious prepartum virilization and remarkably elevated testosterone were observed in the mother, who was initially suspected to have a testosterone-producing ovarian tumor. Clinical phenotypes and hormone profiles of the patient and her mother were investigated. Genotyping analyses of the CYP19A1 gene were performed in the patient and her parents. Functional impairment of the mutations was explored using three-dimensional computer model and mutagenesises in vitro transfection assays. A compound heterozygous mutation of the CYP19A1 gene was revealed in the patient, with a G deletion in nucleotide 264 of exon 3 in one allele and a 23-bp insertion in exon 9 in another allele; both mutations resulted in reading frame-shifts that led to truncated proteins of 87 and 360 amino acids, respectively. Molecular modeling analysis suggested that the two renascent truncated proteins lacked crucial amino acids that were involved in substrate access and catalysis as well as heme-binding region. Functional studies in transfected HEK-293T cells exhibited a nearly complete abolishment of enzyme activity, which may underlie the phenotype and hormone profile. CONCLUSIONS: Two novel CYP19A1 mutations were identified in a Chinese girl born with ambiguous genitalia and severe maternal virilization during pregnancy. Maternal virilization should prompt consideration of aromatase deficiency, preventing unnecessary interventions in pregnancy. This study broadens the spectrum of phenotype and genetic mutations of this rare disorder.