Acupuncture for premature ejaculation: a systematic review and meta-analysis

The role of acupuncture in treating premature ejaculation and its probable neurobiological mechanism

BACKGROUND

Premature ejaculation (PE) is one of the most common diseases in andrology and leads to serious male sexual dysfunction. Although several targeted oral drug therapies are used to treat PE, they often face challenges related to imprecise targeting and adverse effects. Acupuncture has shown potential in prolonging ejaculation time and improving couples' sexual quality of life. This review aims to summarize the benefits of acupuncture in treating PE and explore its probable neurobiological mechanisms.

RESULTS

The review included eight clinical trials involving 679 patients, of which 294 were treated with acupuncture. Furthermore, this review analyzed acupuncture points, needle retention time, treatment duration, and their probable neurobiological mechanisms. The proposed mechanisms include stimulating the frontal functional lobe, inhibiting spinal cord neural pathways, regulating serotonin levels, enhancing 5-hydroxytryptamine receptor IB excitability, reducing penile sensitivity, and modulating hormone levels.

CONCLUSIONS

Acupuncture is a viable alternative or complementary therapy for PE, and neurobiological mechanisms appear to play a key role, but further experimental validation is needed.

Comparing Western and traditional Chinese medicine for male sexual dysfunction: can Klotho represent a silk road?

Traditional Chinese medicine (TCM) and Western Medicine both have shown efficacy in treating male sexual dysfunction (MSD). The aim of this perspective paper is to discuss a possible link between Western medicine and TCM in the MSD field as represented by the entity of Klotho. Klotho is a recently discovered protein, mainly expressed in the kidney, encoded by the anti-aging gene klotho. Not only is Klotho significantly correlated with the development and progression of kidney diseases and their complications, but increasing evidence indicates that it is also closely related to MSD. A comprehensive search within PubMed database was performed to retrieve available evidence on Klotho's roles, particularly in kidney and in MSD. Indeed, in the TCM theory, the concept of the "kidney" is entirely different from the Western medicine: it is closely related to metabolism and to the reproductive, nervous, endocrine systems, being more than just a urinary organ. According to the "Kidney storing essence (jīng) and governing reproduction" (KSEGR) theory, a cornerstone in TCM, the treatment of MSD mainly consists of restoring the kidney's function. Signs of decreasing kidney essence show a consistent similarity to deficiencies of Klotho, also for what regards the male sexual function. Based on the current evidence, Klotho may represent a potential biological indicator for sexual desire and sexual function and a kind of new scientific Silk Road between TCM and Western medicine for MSD; nevertheless, there is a need to conduct further high-quality research to prove this hypothesis.

Altered brain activity associated with premature ejaculation improved by electroacupuncture in rats

Background

Premature ejaculation (PE) is linked with abnormal brain activity that is modifiable by electroacupuncture (EA).

Aim

In this study we aimed to explore the central pathological mechanism underlying EA in treating PE.

Methods

Six-week-old male Sprague-Dawley rats were divided into a PE group (n = 8) and a control group (n = 8) according to ejaculatory frequency during copulatory behavior. All rats underwent EA at the Zusanli acupoint (ST-36) for 4 weeks. Magnetic resonance imaging data were collected before and after EA.

Outcomes

The behavioral parameters, plasma norepinephrine levels, fractional amplitude of low frequency fluctuation (fALFF), and regional homogeneity (ReHo) were evaluated.

Results

The PE group ejaculated more times with shorter latency compared with controls. After EA, the ejaculation frequency of the PE group decreased, and the ejaculation latency period increased, with no changes observed in the control group. Norepinephrine levels were higher in the PE group than in the controls and were positively correlated with ejaculation frequency and negatively correlated with ejaculation latency. The PE group showed lower fALFF in the right striatum and higher ReHo in the brainstem compared with controls. After EA, controls showed decreased fALFF in the right striatum, left olfactory bulb, and dorsal fornix and increased ReHo in the right interpeduncular nucleus, as well as decreased ReHo in the left striatum, prelimbic system, right basal forebrain region, septal region, and olfactory bulb, while the model group exhibited increased fALFF in the right hypothalamic region, decreased fALFF in the left globus pallidum and right basal forebrain region and increased ReHo in the right interpeduncular nucleus, as well as decreased ReHo in the left striatum, olfactory bulb, basal forebrain region, dentate gyrus, right dysgranular insular cortex, and striatum. Compared with the controls after EA, the model group showed increased ReHo of the right hypothalamic region and decreased ReHo of the right dysgranular insular cortex.

Clinical Implications

These findings might enhance the understanding of PE and contribute to new, targeted therapies for PE.

Strengths and Limitations

The therapeutic effects might be achieved by EA inhibiting the activity in brain regions involved in ejaculatory behavior. However, the curative effect of acupuncture might be underestimated due to some curative effects of sham acupuncture used in the control group.

Conclusion

In conclusion, the ejaculatory frequency of rats may be reduced and ejaculation latency could be extended by EA at ST-36, which might be achieved by the effects of this treatment on brain activity.

Effects of CYP2D6 *10 and *41 Variants in Healthy Chinese Men on the Pharmacokinetics of Dapoxetine

Dapoxetine is a selective serotonin reuptake inhibitor (SSRI) used to treat premature ejaculation (PE), and is mainly metabolized by CYP2D6, CYP3A4, and flavin-containing monooxygenase 1. The purpose of the study was to evaluate the effect of CYP2D6 polymorphism on the pharmacokinetics of dapoxetine in healthy Chinese men. Thirty-nine subjects who received a single oral dose of 30 mg dapoxetine hydrochloride were classified based on their CYP2D6 genotype: *1/*1 (n = 9), *1/*41 (n = 1), *1/*10 (n = 12), *10/*41 (n = 3), or *10/*10 (n = 14). The difference in pharmacokinetic parameters between different genotype groups was analyzed and then scored according to the activity score system. Compared with the wild-type subjects of CYP2D6 *1/*1, the peak plasma concentration (Cmax) and the area under the plasma drug concentration-time curve (AUCinf) of dapoxetine in the *10/*10 and *10/*41 groups were notably increased (P ≤ .05). Significant differences in Cmax, AUC, volume of distribution/bioavailability (V/F) and clearance/bioavailability (CL/F) were observed among dapoxetine activity score groups (P ≤ .05). The AUCinf was increased significantly (154% and 89.73%, P ≤ .05) and the Cmax was increased significantly (73.45% and 42.67%, P ≤ .05) in CYP2D6 *10/*41 subjects, compared with CYP2D6 *1/*1 and *1/*10 subjects. The results obtained indicated that CYP2D6 *10 and *41 polymorphisms have significant effects on the pharmacokinetic properties of dapoxetine.