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排序方式: 共有1167条查询结果,搜索用时 15 毫秒
1.
Sarah Alves Auharek Carlos Alexandre Carollo Rodrigo Juliano Oliveira Andra Luiza Cunha‐Laura Antnio Carlos Duenhas Monreal Joo Mximo Siqueira Deiler Sampaio Costa Tammy Reis de Paiva Cond Dayhanne Isa Langkammer Wollf Ernani Aloysio Amaral 《Andrologia》2019,51(8)
Pfaffia glomerata (Spreng.) Pedersen, popularly known as “Brazilian ginseng,” is used as medicinal plant in Brazil to treat inflammatory diseases in general. Previous studies showed that its extract increases the nitric oxide (NO) levels. Knowing that NO downregulates steroidogenesis and that alterations in the action/production of androgens during perinatal life could alter testis development, the present studies sought to investigate the reproductive toxicity of Pfaffia glomerata on male mice exposed to hydroalcoholic extract in utero and during lactation. The present study shows that P. glomerata extract does not alter body weight, tubular diameter and testis function in male mice. Although a reduction in the testis weight was observed in the animals that received the highest dose directly in early post‐natal life, our findings show clearly that P. glomerata may not act as an endocrine disruptor, and it is not an “antiandrogenic” compound that could lead to testicular dysgenesis syndrome. 相似文献
2.
The present study was performed to show the ameliorative effect of berberine (BBR), as an antioxidant and anti‐inflammatory agent, against experimental varicocele (VCL)‐induced molecular and histological damages. For this purpose, 50 mature Wistar rats were divided into control, control‐sham, VCL‐sole, 50 mg/kg and 100 mg/kg BBR‐treated VCL‐induced groups. The tissue levels of interleukin‐6 (IL‐6), tumour necrosis factor‐α (TNF‐α), nitric oxide (NO), total antioxidant capacity (TAC), malondialdehyde (MDA), superoxide dismutase (SOD) and gluthatione peroxidase (GSH‐px) as well as the mRNA levels of testicular CuZn SOD, MnSOD, EC‐SOD and GSH‐px were evaluated. The serum concentration of testosterone and germ cells mRNA damage were analysed. Finally, the sperm viability, motility, DNA integrity and chromatin condensation were analysed. Observations revealed that, the BBR significantly downregulated VCL‐increased IL‐6, TNF‐α and NO levels, upregulated the CuZn SOD, MnSOD, EC‐SOD and GSH‐px mRNA level, decreased testicular MDA content, enhanced serum testosterone level and ameliorated testicular TAC, SOD and GSH‐px levels. The animals in BBR‐treated groups exhibited diminished mRNA damage versus non‐treated VCL‐induced group. The BBR has significantly (p < 0.05) improved sperm parameters. In conclusion, the BBR by promoting testicular antioxidant potential and by downregulating inflammatory reactions fairly promotes spermatogenesis and upregulates the sperm quality. 相似文献
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Dietary cholesterol and oxidised cholesterol: effects on sperm characteristics,antioxidant status and hormonal profile in rats 下载免费PDF全文
Present study was designed to compare the potential effects of high serum levels of LDL and oxidised LDL (OxLDL) on spermatogenesis parameters in male Wistar rats. Animals were allocated into three groups and were fed for 14 weeks with normal, cholesterol‐rich and oxidised cholesterol‐rich diets. Blood lipid profile, sex hormones level, as well as sex organs weight were evaluated. The sex organs weight in oxidised cholesterol‐fed group was significantly reduced (P < 0.05). Spermatozoa count in the group with high serum concentration of OxLDL (64 ± 4.2 × 106) was markedly lower (P < 0.01) than that of normal rats (87 ± 4.1 × 106) and rats with high serum level of LDL (90 ± 6.3 × 106). Similarly, the percentage of viable spermatozoa was significantly (P < 0.001) decreased from 78% to 52% by high level of OxLDL in serum. While, nonoxidised LDL did not have suppressive effects on spermatogenesis and organs weight. Consistent with these effects, the serum concentration of sex hormones including FSH (P < 0.001), LH (P < 0.001) and testosterone (P < 0.01) was significantly decreased only in rats with high level of OxLDL but not in rats with high level of nonoxidised LDL. In conclusion, high OxLDL level showed higher destructive effect on reproductive system compared to the high LDL level. 相似文献
7.
Meng Rao Xiao-Ling Zhao Jing Yang Shi-Fu Hu Hui Lei Wei Xia Chang-Hong Zhu 《Asian journal of andrology》2015,17(4):668-675
In this experimental prospective study, we aimed to analyze the effect of transient scrotal hyperthermia on the male reproductive organs, from the perspective of sperm parameters, semen plasma biochemical markers, and oxidative stress, to evaluate whether different frequencies of heat exposure cause different degrees of damage to spermatogenesis. Two groups of volunteers (10 per group) received testicular warming in a 43°C water bath 10 times, for 30 min each time: group 1: 10 consecutive days; group 2: once every 3 days. Sperm parameters, epididymis and accessory sex gland function, semen plasma oxidative stress and serum sex hormones were tested before treatment and in the 16-week recovery period after treatment. At last, we found an obvious reversible decrease in sperm concentration (P = 0.005 for Group 1 and P= 0.008 for Group 2 when the minimums were compared with baseline levels, the same below), motility (P = 0.009 and 0.021, respectively), the hypoosmotic swelling test score (P = 0.007 and 0.008, respectively), total acrosin activity (P = 0.018 and 0.009, respectively), and an increase in the seminal plasma malondialdehyde concentration (P = 0.005 and 0.017, respectively). The decrease of sperm concentration was greater for Group 2 than for Group 1 (P = 0.031). We concluded that transient scrotal hyperthermia seriously, but reversibly, negatively affected the spermatogenesis, oxidative stress may be involved in this process. In addition, intermittent heat exposure more seriously suppresses the spermatogenesis compared to consecutive heat exposure. This may be indicative for clinical infertility etiology analysis and the design of contraceptive methods based on heat stress. 相似文献
8.
Ranjith Ramasamy Joseph M Armstrong Larry I Lipshultz 《Asian journal of andrology》2015,17(2):197-200
An increasing number of young and middle-aged men are seeking treatment for symptoms related to deficient levels of androgens (hypogonadism) including depression, loss of libido, erectile dysfunction, and fatigue. The increase in prevalence of testosterone supplementation in general and anabolic steroid-induced hypogonadism specifically among younger athletes is creating a population of young men who are uniquely impacted by the testicular end-organ negative consequences of exogenous steroid use. Exogenous testosterone therapy can alter the natural regulation of the hypothalamic-pituitary-gonadal axis leading to impaired spermatogenesis with azoospermia being a serious possible result, thus rendering the individual infertile. For men of reproductive age who suffer from hypogonadal symptoms, preservation of fertility is an important aspect of their treatment paradigm. Treatment with human chorionic gonadotropin (hCG) has shown the ability not only to reverse azoospermia brought on by testosterone supplementation therapy but also to help maintain elevated intratesticular testosterone levels. In addition, selective estrogen receptor modulators, often used with hCG have been shown both to elevate total testosterone levels and to maintain spermatogenesis in hypogonadal men. 相似文献
9.
Daniel E. Nassau Jordan C. Best Eliyahu Kresch Daniel C. Gonzalez Kajal Khodamoradi Ranjith Ramasamy 《BJU international》2022,129(2):143-150
The coronavirus 2019 (COVID-19) pandemic caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to more than 160 million infections and 3.5 million deaths globally. Men are disproportionately affected by COVID-19, having more severe disease with higher mortality rates than women. Androgens have been implicated as the underlying cause for more severe disease, as the androgen receptor has been noted to upregulate the cell surface receptors that mediate viral cell entry and infection. Unfortunately, despite testosterone’s potential role in COVID-19 prognosis, androgen deprivation therapy is neither protective nor a treatment for COVID-19. Interestingly, the male reproductive organs have been found to be vulnerable in moderate to severe illness, leading to reports of erectile dysfunction and orchitis. COVID-19 viral particles have been identified in penile and testis tissue, both in live patients who recovered from COVID-19 and post mortem in men who succumbed to the disease. Although sexual transmission remains unlikely in recovered men, moderate to severe COVID-19 infection can lead to germ cell and Leydig cell depletion, leading to decreased spermatogenesis and male hypogonadism. The objective of this review is to describe the impact of SARS-CoV-2 on male reproductive health. There are still many unanswered questions as to the specific underlying mechanisms by which COVID-19 impacts male reproductive organs and the long-term sequelae of SARS-CoV-2 on male reproductive health. 相似文献
10.
Osman Barut Muhammed Seyithanoglu Faruk Kucukdurmaz Bekir Turkay Demir Caner Olmez Neslihan Temiz Dogan Sefa Resim 《Andrologia》2020,52(10):e13779
The aim of this study was to investigate the diagnostic value of serum G protein–coupled oestrogen receptor (GPER) levels and their correlation with semen parameters in men with infertility. The participants were divided into two groups as follows: 76 fertile control men (Group 1) and 77 infertile men (Group 2). Semen analysis, hormonal evaluation, serum GPER level and scrotal ultrasound of the participants were evaluated. Follicle-stimulating hormone and total testosterone levels were not significantly different between the groups (p = .413 and p = .535 respectively). The oestradiol level in Group 1 was significantly lower than that in Group 2 (p < .001). The serum GPER level was found to be significantly higher in Group 1 than that of Group 2 (p < .001). GPER levels were positively correlated with the total sperm count, sperm concentration, motility and morphology in Group 2 (r = 0.303, 0.345, 0.260 and 0.322, respectively, p < .001). In this study, GPER levels were positively correlated with sperm parameters, and it was hypothesised that the decrease in GPER expression might be associated with male infertility by adversely affecting spermatogenesis. 相似文献