Neurons for Ejaculation and Factors Affecting Ejaculation

Exploring the impact of sexual positions on ejaculation: Insights from a survey study by the Andrology Working Group of the Society of Urological Surgery in Turkey

BACKGROUND

Sexual position is one of the several aspects that affects ejaculation control, which is essential for sexual pleasure. Still little is known, nevertheless, about the connection between sexual positions and ejaculation duration.

OBJECTIVE

To investigate the impact of various sexual positions on the duration of ejaculation and gain a deeper understanding of the elements that influence the ability to control ejaculation.

METHOD

An online survey was carried out on a sample of 1904 heterosexual men between the ages of 18-65 years. Premature ejaculation (PE) diagnostic tool was used to define PE. Demographic, behavioral, and physiological traits that are linked to PE and non-PE groups were collected. The participants listed their preferred sexual positions and the ones they changed to during ejaculating. Also, analyses were performed between male/female active or deep/shallow thrust positions and PE status.

RESULTS

Although there were no appreciable variations in age or circumcision between PE and non-PE groups, the age of first sexual experience was associated with PE status. Groups also varied in the number of weekly ejaculations, the duration of the favored ejaculations, and the characteristics of the erection. The most preferred sexual posture was the doggy style regardless of the group. When the non-PE group felt to ejaculate, they preferred to change the position significantly more than the PE group (74% vs 67.2%; p < 0.05). However, when participants felt ejaculate, non-PE participants tended to switch to shallow thrusting positions significantly more than PE participants, who preferred deeper positions (27.1% vs. 18%; p < 0.05).

CONCLUSION

This study underlines the relevance of considering sexual positions in controlling PE. Modifying positions during sexual intercourse may offer a non-pharmacological therapeutic alternative for improving ejaculation control. Future studies in this field might help to create tailored PE treatment strategies.

Retrograde Ejaculation Due to Posterior Urethral Stricture: A Rare Case Report

Pelvic fracture is a serious injury, which has a profound impact on sexual function due to concurrent nervous and urethral injuries. In this case report, we describe a 29-year-old single man who had retrograde ejaculation as a result of a pelvic fracture-related posterior urethral stricture. The patient wanted to improve his ejaculatory ability after experiencing urethral stricture for 8 years and retrograde ejaculation for 3 years following the pelvic fracture. We precisely located and measured the patient's urethral stricture using a retrograde urethrogram, and we used transrectal color Doppler ultrasound to track the patient's ejaculation process in real time. Next, we used urethral balloon dilatation to relieve the urethral stricture. Urinary obstruction symptoms have completely resolved, and the patient was able to urinate without any obstructions. Meanwhile, the real-time transrectal color Doppler ultrasound result showed that some semen might ejaculate externally by passing through the initial stricture area, while some semen continued to flow retrogradely into the bladder.

Peripheral pathway gene variants in lifelong premature ejaculation: CYP19A1, CYP1A1, and CYP1A2 enzymes polymorphisms in Chinese Han men

Background

Recent genetic association studies focusing on central pathways have been performed to investigate the correlation between susceptibility alleles and the risk of lifelong premature ejaculation (LPE). However, there remains a dearth of documented genes associated with peripheral pathways.

Objective

In this study we aimed to investigate the relationship between single nucleotide polymorphisms (SNPs) associated with the peripheral genes CYP19A1, CYP1A1, and CYP1A2 and the risk of LPE.

Methods

From August 2017 to August 2020, a total of 511 participants (139 LPE patients and 372 controls) were recruited. Trained medical professionals diagnosed LPE according to the standard definition set by the International Society for Sexual Medicine. Nine candidate SNPs were chosen and genotyped using the MassARRAY system. Allele and genotype frequencies of the SNPs among patients and controls were compared using the χ2 test. Logistic regression analysis, adjusted for age, was performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs) using PLINK version 1.9. Haploview software was employed to analyze linkage disequilibrium and haplotype distribution. The interaction among candidate SNPs concerning LPE risk was evaluated using multifactor dimensionality reduction. The relationship between selected polymorphisms and specific features was assessed using analysis of variance.

Outcome

Heterozygous SNPs located in the CYP19A1 (rs4646, rs17601876), CYP1A1 (rs1048943), and CYP1A2 (rs762551, rs2470890) genes showed significant correlations with the risk of LPE.

Results

The findings of this study confirmed that heterozygous SNPs in the CYP19A1 (rs4646 AC vs CC: OR, 1.84; CI, 1.10-3.09; rs17601876 AG vs GG: OR, 1.80; CI, 1.06-3.05) and CYP1A1 genes (rs1048943 CT vs TT: OR, 1.71; CI, 1.02-2.87), respectively, can significantly increase the LPE risk. Participant scores for the Premature Ejaculation Diagnostic Tool (P =.002) and International Index of Erectile Function-5 (P =.020) differed significantly by genotype for the different genotypes of CYP1A1-rs1048943. Haplotype analysis revealed strong linkage disequilibrium under CYP1A2_rs762551-rs2470890 (D' = 1.00).

Clinical Implications

The findings of this and other investigations of genetic determinants and potential pathogenic mechanisms of LPE may advance diagnostic and therapeutic opportunities in LPE patients.

Strengths and Limitations

In this study of LPE in men with CYP gene variants we addressed a current research gap. However, data on risk factors such as smoking and drinking were incomplete in both the case and control groups. In future studies we will expand the sample size and enhance data on risk factors for more precise assessments.

Conclusion

In summary, polymorphisms in the peripheral genes CYP19A1, CYP1A1, and CYP1A2 may play a role in LPE among Chinese men of the Han population.

Characterization of a novel adipose tissue located between abdominal lymph nodes and cervix/prostate in mice

Perigonadal adipose tissue is a homogeneous white adipose tissue (WAT) in adult male mice without any brown adipose tissue (BAT). However, there are congenital differences in the gonads between male and female mice. Whether heterogeneity existed in perigonadal adipose tissues (ATs) in female mice remains unknown. This study reported a perigonadal brown-like AT located between abdominal lymph nodes and the uterine cervix in female mice, termed lymph node-cervical adipose tissue (LNCAT). Its counterpart, lymph node-prostatic adipose tissue (LNPAT), exhibited white phenotype in adult virgin male mice. When exposed to cold, LNCAT/LNPAT increased uncoupling protein 1 (UCP1) expression via activation of tyrosine hydroxylase (TH), in which abdominal lymph nodes were involved. Interestingly, the UCP1 expression in LNCAT/LNPAT varied under different reproductive stages. The UCP1 expression in LNCAT was upregulated at early pregnancy, declined at midlate pregnancy, and reverted in weaning dams. Mating behavior stimulated LNPAT browning in male mice. We found that androgen but not estrogen or progesterone inhibited UCP1 expression in LNCAT. Androgen administration reversed the castration-induced LNPAT browning. Our results identified a perigonadal brown-like AT in female mice and characterized its UCP1 expression patterns under various conditions.NEW & NOTEWORTHY A novel perigonadal brown-like AT (LNCAT) of female mice was identified. Abdominal lymph nodes were involved in cold-induced browning in this newly discovered adipose tissue. The UCP1 expression in LNCAT/LNPAT was also related to ages, sexes, and reproductive stages, in which androgen acted as an inhibitor role.

Stress Biomarkers Transferred Into the Female Reproductive Tract by Seminal Plasma Are Associated with ICSI Outcomes

This study aimed to determine whether male stress is related to seminal stress biomarkers and pregnancy achievement in women exposed to their partner's seminal plasma (SP) in the intracytoplasmic sperm injection (ICSI) cycle. In this pilot prospective study, 20 couples undergoing ICSI, as well as 5 fertile sperm donors and 10 saliva donors, were investigated. Women were exposed to their partner's SP via unprotected sexual intercourse during the ICSI cycle and intravaginal application on the day of ovum pick-up (Day-OPU). Semen samples were collected from male partners by masturbation on the Day-OPU. Saliva and serum samples were collected prior to masturbation. Body fluids were frozen at - 80 °C until assayed. Biomarkers of activity of the sympathetic adrenomedullary axis (salivary alpha-amylase and adrenaline), sympathetic neural axis (noradrenaline and dopamine), hypothalamic-pituitary-adrenal (HPA) system (cortisol), and immune system (C-reactive protein and interleukin (IL)-18) were estimated to examine their association with SP composition and clinical pregnancy achievement. The clinical pregnancy rate was 45.0%. In the unsuccessful ICSI group, blunted levels of salivary and serum cortisol were found compared to the successful ICSI group and the fertile sperm donors. With regard to seminal markers, decreased cortisol level and elevated noradrenaline, noradrenaline/cortisol ratio, and lL-18 levels were strongly associated with ICSI failure (areas under the ROC curves were, 0.813, 0.848, 0.899, and 0.828, respectively). These findings confirm that stress response systems activity affects SP composition, which in turn is associated with ICSI outcomes in women exposed to their partner's SP during an ICSI cycle.

Topological differences of striato-thalamo-cortical circuit in functional brain network between premature ejaculation patients with and without depression

INTRODUCTION

Premature ejaculation (PE), a common male sexual dysfunction, often accompanies by abnormal psychological factors, such as depression. Recent neuroimaging studies have revealed structural and functional brain abnormalities in PE patients. However, there is limited neurological evidence supporting the comorbidity of PE and depression. This study aimed to explore the topological changes of the functional brain networks of PE patients with depression.

METHODS

Resting-state functional magnetic resonance imaging (rs-fMRI) data were acquired from 60 PE patients (30 with depression and 30 without depression) and 29 healthy controls (HCs). Functional brain networks were constructed for all participants based on rs-fMRI data. The nodal parameters including nodal centrality and efficiency were calculated by the method of graph theory analysis and then compared between groups. In addition, the results were corrected for multiple comparisons by family-wise error (FWE) (p < .05).

RESULTS

PE patients with depression had increased degree centrality and global efficiency in the right pallidum, as well as increased degree centrality in the right thalamus when compared with HCs. PE patients without depression showed increased degree centrality in the right pallidum and thalamus, as well as increased global efficiency in the right precuneus, pallidum, and thalamus when compared with HCs. PE patients with depression demonstrated decreased degree centrality in the right pallidum and thalamus, as well as decreased global efficiency in the right precuneus, pallidum, and thalamus when compared to those without depression. All the brain regions above survived the FWE correction.

CONCLUSION

The results suggested that increased and decreased functional connectivity, as well as the capability of global integration of information in the brain, might be related to the occurrence of PE and the comorbidity depression in PE patients, respectively. These findings provided new insights into the understanding of the pathological mechanisms underlying PE and those with depression.

Fertility Challenges: The Complexities of Retrograde Ejaculation and Cornual Block in Reproductive Health

Infertility, a complicated reproductive health issue that affects both men and women, can have a variety of causes, from anatomical abnormalities to hormone imbalances. This research addresses a couple who have been struggling with infertility for the past four years: a 31-year-old woman with bilateral tubal blockage and her 34-year-old spouse who suffered from primary infertility due to retrograde ejaculation (RE) for the same period. Analyzing the male's semen sample, it was discovered that there were dead sperm and urine, indicating RE. A hysterosalpingography indicated bilateral tubal obstruction in the female partner. Pelvic factors were examined via laparoscopy, which played a crucial role in addressing further issues. The procedure of treatment included testicular sperm aspiration for sperm extraction and intracytoplasmic sperm injection. Hormonal support was involved in the follow-up, and on the 14th day, the β-hCG test came back positive. The intricate procedures of RE and cornual block are discussed, with a focus on how they affect reproductive health.

The elusive concept of sexual motivation: can it be anchored in the nervous system?

Sexual motivation is an abstract concept referring to the mechanisms determining the responsivity to sexually relevant stimuli. This responsivity determines the likelihood of producing a sexual response and the intensity of that response. Both responsivity to stimuli and the likelihood of making a response as well as the intensity of response are characteristics of an individual. Therefore, we need to assume that the concept of sexual motivation materializes in physiological mechanisms within the individual. The aim of the present communication is to analyze the requisites for the endeavor to materialize sexual motivation. The first requisite is to provide an operational definition, making the concept quantifiable. We show that parameters of copulatory behavior are inappropriate. We argue that the intensity of sexual approach behaviors provides the best estimate of sexual motivation in non-human animals, whereas the magnitude of genital responses is an exquisite indicator of human sexual motivation. Having assured how to quantify sexual motivation, we can then proceed to the search for physiological or neurobiological underpinnings. In fact, sexual motivation only manifests itself in animals exposed to appropriate amounts of gonadal hormones. In female rats, the estrogen receptor α in the ventrolateral part of the ventromedial nucleus of the hypothalamus is necessary for the expression of sexual approach behaviors. In male rats, androgen receptors within the medial preoptic area are crucial. Thus, in rats sexual motivation can be localized to specific brain structures, and even to specific cells within these structures. In humans, it is not even known if sexual motivation is materialized in the brain or in peripheral structures. Substantial efforts have been made to determine the relationship between the activity of neurotransmitters and the intensity of sexual motivation, particularly in rodents. The results of this effort have been meager. Likewise, efforts of finding drugs to stimulate sexual motivation, particularly in women complaining of low sexual desire, have produced dismal results. In sum, it appears that the abstract concept of sexual motivation can be reliably quantified, and the neurobiological bases can be described in non-human animals. In humans, objective quantification is feasible, but the neurobiological substrate remains enigmatic.

Piezo-mediated mechanosensation contributes to stabilizing copulation posture and reproductive success in Drosophila males

In internal fertilization animals, reproductive success depends on maintaining copulation until gametes are transported from male to female. In Drosophila melanogaster, mechanosensation in males likely contributes to copulation maintenance, but its molecular underpinning remains to be identified. Here we show that the mechanosensory gene piezo and its' expressing neurons are responsible for copulation maintenance. An RNA-seq database search and subsequent mutant analysis revealed the importance of piezo for maintaining male copulation posture. piezo-GAL4-positive signals were found in the sensory neurons of male genitalia bristles, and optogenetic inhibition of piezo-expressing neurons in the posterior side of the male body during copulation destabilized posture and terminated copulation. Our findings suggest that the mechanosensory system of male genitalia through Piezo channels plays a key role in copulation maintenance and indicate that Piezo may increase male fitness during copulation in flies.

Effects of One-Shot Hyaluronic Acid Injection in Lifelong Premature Ejaculation: A Pilot Study

The therapeutic management of premature lifelong ejaculation (PE) ranges from behavioral therapy to pharmacological and surgical treatments. Hyaluronic Acid (HA) injection into the glans penis is a non-surgical procedure, intended to reduce glans hypersensitivity, improving the intravaginal ejaculation latency time (IELT). HA injection can be performed through different techniques that, although safe and effective, rarely can cause local complications. In this pilot uncontrolled study, we tested the effectiveness of a new technique based on a single HA injection into the frenulum of the glans, to improve IELT in a sample of patients affected by PE. We observed a significant increase of the IELT after one (median 73.3, IQR 66.2–79.9 s) and two months (66.2, 63.1–73.9) that gradually decreased at three months, remaining still significantly higher than at baseline (34.8, 30.9–37.4). PEDT and IIEF questionnaires significantly improved compared to baseline in the first two months of follow-up (p < 0.001). In conclusion, the preliminary results emerging from this pilot uncontrolled study, highlight the effectiveness of this one-shot HA injection approach, although a larger sample and longer follow-up time are needed to standardize the procedure.

Erectile Dysfunction in Relation to Metabolic Disorders and the Concentration of Sex Hormones in Aging Men

Background: The aim of this study was to analyze the relationship between the prevalence of erectile dysfunction in men as diagnosed by the International Index of Erectile Function (IIEF) questionnaire and the respective levels of sex hormones and biochemical parameters, as well as indices of visceral fat accumulation and activity. Material and Methods: The study comprised 148 male (60–75 years) patients from primary care outpatient clinics in the city of Szczecin (Poland). The men were asked to complete a shortened survey questionnaire with sociodemographic data, as well as a shortened version of the IIEF (five items). Venous blood samples were collected. Total testosterone (TT), estradiol (E2), sex hormone-binding globulin (SHBG), dehydroepiandrosterone sulfate (DHEAS), total cholesterol (ChT), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG), fasting plasma glucose (FPG) and albumin were determined. Lipid accumulation product (LAP) and visceral adiposity index (VAI) were calculated. Results: A correlation was found in the analysis of LAP index values (OR = 1.017; p = 0.050). The analysis of hormone concentrations showed a correlation between the diagnosed trait and the value of TT (OR = 1.216; p = 0.046) and SHBG (OR = 1.020; p = 0.007). Conclusions: VAI and LAP have been shown to be good indicators for assessing erectile dysfunction in men over 60 years of age.