Effect of lipoic acid supplementation on gene expression and activity of glutathione S-transferase enzyme in infertile men

Assessment of Electroacupuncture Therapy with Distant-Approximal Acupoints Based on the HPT Axis in Rats with Oligoasthenospermia Through Transcriptomic Analysis

The transcriptomic analysis was used to explore the effect of electroacupuncture therapy with distant-approximal acupoints based on the hypothalamic-pituitary-testicular (HPT) on gene expression patterns and pathways in oligoasthenospermia (OAT) rats. In this study, the rat model of OAT after intragastric administration of adenine was selected as the research object, and randomly divided into a blank group (C), a model group (M), and a electroacupuncture therapy with distant-approximal acupoints group (D). After electroacupuncture intervention, the epididymal sperm quality and serum sex hormone levels of rats was detected and three tissue samples of HPT axis were taken, and differentially expressed genes (DEGs) were screened by transcriptome sequencing technology. GO functional annotation and KEGG pathway enrichment analysis were performed on the DEGs. The oxidative stress related indicators in serum and HPT axis were also detected to verify the transcriptomic analysis results. Compared with group C, group M rats showed a decrease in sperm count (p < 0.001), sperm survival rate (p < 0.001), and sperm motility rate (p < 0.001); the serum levels of GnRH in the group M rats decreased (p < 0.001), FSH increased (p < 0.001), LH increased (p < 0.001), and T decreased (p < 0.001). Compared with group M, group D rats showed an increase in sperm count (p < 0.01), sperm survival rate (p < 0.001), sperm motility rate (p < 0.001), an increase in GnRH levels (p < 0.001), a decrease in FSH levels (p < 0.01), a decrease in LH levels (p < 0.001), and an increase in T levels (p < 0.001). In bioinformatics analysis, compared with group M, we identified 1656, 518, 530 DEGs in the hypothalamus, pituitary, and testis in group D, respectively. Combining the go and KEGG analysis results, three oxidative stress signaling pathways that may be related to electroacupuncture intervention in OAT rats were screened. It mainly involves the glutamatergic synaptic pathway, the MAPK signaling pathway and the glutathione metabolism pathway. Six key genes (Gng12、Grin1、Gng7、Jun、Nf1 and Gstp1) were identified as key candidate genes regulating epididymal sperm quality on the HPT axis, which may affect the reproductive function of rats by affecting the process of oxidative stress in vivo. No matter in serum or in three tissues of HPT axis, GPX4 level in group M was decreased compared with Group K (p < 0.0001), while GPX4 level in group D was increased compared with group M (p < 0.0001). This study found that the effect of electroacupuncture therapy with distant-approximal acupoints based on the HPT axis in rats with OAT is related to the process of oxidative stress. And the main genes involved in the oxidative stress pathway were identified, which provided directions and ideas for subsequent research. But these results are only the preliminary results of transcriptomics, and relevant experiments need to be designed to further verify the mechanism of electroacupuncture therapy in rats with OAT.

Role of Lipoic Acid in Testosterone Production in Males

Testosterone extends its impact beyond sexual function, playing a crucial role in shaping overall male health, including aspects such as muscle mass, bone density, mood regulation, and energy levels. Lipoic acid, a cofactor for specific enzymes, particularly dehydrogenases involved in cellular energy production, has been studied for its impact on testosterone. This comprehensive review systematically scoured PubMed and Scopus databases using the keywords "lipoic acid" and "testosterone." It encompassed all relevant English papers published from November 1971 to the present, including full texts and abstracts, along with research elucidating the biochemical mechanisms linking lipoic acid to testosterone. In summary, lipoic acid consistently restores testosterone levels, offering promise as an intervention in testicular health, especially in cases of testicular toxicity caused by various harmful agents. Its mechanisms encompass nitric oxide enhancement, fortification of testicular antioxidants, elevation of luteinizing hormone, enhancement of steroidogenesis, and the maintenance of energy production. These mechanisms underscore the therapeutic potential of lipoic acid for testicular health.

Maternal supplementation of alpha-lipoic acid ameliorates prenatal cytarabine-induced mutilation in reproductive development and function in F1 male adult rats

AIMS

Cytarabine (CYT), a prevalent anticancer drug for blood cancers, detrimentally affects male reproductive development and function. Alpha-lipoic acid (ALA), a universal antioxidant, offers defense against chemical-induced reproductive dysfunction. Our study sought to explore ALA's protective role against prenatal CYT-induced reproductive impairment in F1 male adult rats.

MAIN METHODS

Pregnant rats were divided into 5 groups and administered normal saline, ALA 200 mg/kg, CYT 12.5 mg/kg, CYT 25 mg/kg, and CYT 25 mg/kg + ALA 200 mg/ kg from gestational day 8 to 21. On postnatal day 73, F1 male rats were sacrificed, and general, oxidative, steroidogenic, spermatogenic, histological, and morphometrical parameters were evaluated.

KEY FINDINGS

Prenatal CYT caused dose-dependent reductions in body weight, testis, and accessory gland weights; elevated oxidative stress; delayed puberty onset; sperm anomalies (decreased count, motility, viability, seminal fructose; increased morphological anomalies); impeded steroidogenesis (lower testosterone, follicle-stimulating hormone, luteinizing hormone, 3β-Hydroxysteroid dehydrogenase(HSD), 17β-HSD, and elevated cholesterol); and testicular histopathological and morphometric disturbances. Maternal supplementation of ALA was found to alleviate all the CYT-induced reproductive disruptions.

SIGNIFICANCE

The present work accentuates the beneficial actions of ALA against CYT-induced impairment in reproductive development and functions by combating disruptions in oxidative balance, steroidogenesis, spermatogenesis, and testicular histological aberrations. However, future experimental and clinical studies are warranted to explore the molecular mechanisms involved in the ALA's protection against prenatal CYT-induced testicular injury.

Do "testosterone boosters" really increase serum total testosterone? A systematic review

Testosterone boosters are heavily marketed on social media and marketplaces to men with claims to significantly increase testosterone. Lax industry regulation has allowed sales of supplements to thrive in the absence of verification of their purported benefits. Our primary objective was to systematically review all data published in the last two decades on testosterone boosters and determine their efficacy. Our outcome of interest was total testosterone increase versus placebo in four different populations: male athletes, men with late-onset hypogonadism infertile men and healthy men. Following search and screening, 52 studies were included in our review, relating to 27 proposed testosterone boosters: 10 studies of cholecalciferol; 5 zinc/magnesium; 4 Tribulus terrestris and creatine; 3 Eurycoma longifolia and Withania somnifera; 2 betaine, D-aspartic acid, Lepidium meyenii and isoflavones; while the remainder were single reports. Our findings indicate that most fail to increase total testosterone. The exceptions were β-hydroxy β-methylbutyrate and betaine, which can be considered effective for male athletes. Eurycoma longifolia, a blend of Punica granatum fruit rind and Theobroma cacao seed extracts (Tesnor™) and purified Shilajit extract (PrimaVie™) can be considered possibly effective for men with late-onset hypogonadism; Eurycoma longifolia and Withania somnifera possibly effective for healthy men; and a non-hormonal aromatase inhibitor (Novadex XT™) possibly effective for male athletes.

Hypoxia-Induced GST1 Exerts Protective Effects on Trophoblasts via Inhibiting Reactive Oxygen Species (ROS) Accumulation

Hypoxic conditions are a typical extrinsic factor for the modification of trophoblast biological functions, including cell proliferation, migration, and invasion. Hypoxia-induced reactive oxygen species (ROS) accumulation causes chronic trophoblast injury and contributes to preeclampsia (PE). Glutathione-S-transferase P (GSTP1) is a main regulator of ROS. However, it is still unknown whether GSTP1 is involved in ROS regulation under hypoxic conditions. Here, we investigated the expression level of GSTP1 in first-trimester villi placentas compared with full-term placentas and the effect of hypoxic conditions on GSTP1. GSTP1 expression in first-trimester villi placentas was much higher than that in full-term placentas. After hypoxia exposure, GSTP1 was significantly upregulated in JEG3 cells, a trophoblast-like cell line. Hypoxic-induced GSTP1 scavenged ROS accumulated by hypoxia exposure, potentially by promoting GST activity. The inhibitory effects of hypoxia exposure on cell proliferation, migration, and invasion induced by hypoxia exposure were obviously reversed by overexpression of GSTP1. Hypoxia-induced cell apoptosis was also reversed by GSTP1 overexpression, indicating the protective effects of GSTP1 against ROS-induced cell injury. Moreover, overexpressed GSTP1 markedly promoted the cell proliferation, migration, invasion, and colony formation abilities in JEG3 cells, demonstrating that GSP1 also exerts promoting effects under normoxic conditions. These data show that hypoxia-induced GSTP1 expression facilitates trophoblast cell proliferation, migration, and invasion and exerts protective effects under hypoxic conditions, which may play an important role during the increase in PE.

The effect of alpha-lipoic acid on sperm functions in rodent models for male infertility: A systematic review

In this systematic review, we assessed different studies to evaluate the protective effect of alpha-lipoic acid (ALA), as a multifaceted antioxidant, on sperm functions in rodent models. Four databases were searched to find papers reporting the effect of ALA treatment on animal models of male infertility. Up to December 2022, 11,787 articles were identified to explain the ALA protective effects. The included studies were evaluated for eligibility and risk of bias (CRD42022341370). Finally, we identified 23 studies that explain the effect of ALA on sperm functions in rodents. Among them, 15 studies indicated that ALA could restore sperm parameters. Six studies showed a significant reduction in sperm DNA damage by ALA treatment. Seventeen papers displayed the ALA antioxidant ability, and four studies indicated the ALA anti-inflammatory effect. Besides, thirteen studies displayed that ALA could modulate androgenesis. Also, eighteen studies revealed that ALA restored the testicular architecture to normal, and was also effective in restoring reproductive performance in two included studies. This systematic review provided cogent evidence for the protective effect of ALA in rodent models for male infertility by re-establishing spermatogenesis and steroidogenesis and maintaining redox and immune systems homeostasis.

α-Lipoic Acid Strengthens the Antioxidant Barrier and Reduces Oxidative, Nitrosative, and Glycative Damage, as well as Inhibits Inflammation and Apoptosis in the Hypothalamus but Not in the Cerebral Cortex of Insulin-Resistant Rats

The research determined the role of α-lipoic acid (ALA) in reducing the brain manifestations of insulin resistance. The mechanism of ALA action is mainly based on its ability to “scavenge” oxygen free radicals and stimulate biosynthesis of reduced glutathione (GSH), considered the most critical brain antioxidant. Although the protective effect of ALA is widely documented in various diseases, there are still no studies assessing the influence of ALA on brain metabolism in the context of insulin resistance and type 2 diabetes. The experiment was conducted on male Wistar rats fed a high-fat diet for ten weeks with intragastric administration of ALA for four weeks. We are the first to demonstrate that ALA improves the function of enzymatic and nonenzymatic brain antioxidant systems, but the protective effects of ALA were mainly observed in the hypothalamus of insulin-resistant rats. Indeed, ALA caused a significant increase in superoxide dismutase, catalase, peroxidase, and glutathione reductase activities, as well as GSH concentration and redox potential ([GSH]²/[GSSG]) in the hypothalamus of HFD-fed rats. A consequence of antioxidant barrier enhancement by ALA is the reduction of oxidation, glycation, and nitration of brain proteins, lipids, and DNA. The protective effects of ALA result from hypothalamic activation of the transcription factor Nrf2 and inhibition of NF-κB. In the hypothalamus of insulin-resistant rats, we demonstrated reduced levels of oxidation (AOPP) and glycation (AGE) protein products, 4-hydroxynoneal, 8-isoprostanes, and 3-nitrotyrosine and, in the cerebral cortex, lower levels of 8-hydroxydeoxyguanosine and peroxynitrite. In addition, we demonstrated that ALA decreases levels of proinflammatory TNF-α but also increases the synthesis of anti-inflammatory IL-10 in the hypothalamus of insulin-resistant rats. ALA also prevents neuronal apoptosis, confirming its multidirectional effects within the brain. Interestingly, we have shown no correlation between brain and serum/plasma oxidative stress biomarkers, indicating the different nature of redox imbalance at the central and systemic levels. To summarize, ALA improves antioxidant balance and diminishes oxidative/glycative stress, protein nitrosative damage, inflammation, and apoptosis, mainly in the hypothalamus of insulin-resistant rats. Further studies are needed to determine the molecular mechanism of ALA action within the brain.

Effects of α-lipoic acid and myo-inositol supplementation on the oocyte environment of infertile obese women: A preliminary study

Obesity is becoming pandemic and is associated with impaired reproductive potential. Oxidative stress, low-grade chronic inflammation and mitochondrial dysfunctions, which characterize obesity, strongly affect oocyte environment and function. Supplementation with antioxidant and anti-inflammatory compounds has been suggested to improve fertility. Here we evaluated the effect of α-lipoic acid and myo-inositol supplementation on the oocyte environment of infertile obese women. Nineteen normal-weight and twenty-three obese women, infertile for non-ovarian reasons, were recruited. For two months before ovarian stimulation, all women received 400 μg/die folic acid, whereas 15 obese were additionally supplemented with 800 mg α-lipoic acid, 2 g myo-inositol/die. Antioxidant capacity was measured in follicular fluid by enzymatic assay; mitochondrial DNA (mtDNA) content and mRNA levels of two respiratory chain subunits were analyzed in granulosa cells by Real-time PCR. Pregnancy rate was similar between normal-weight and treated obese, and lower in untreated obese patients. Supplemented women showed significantly higher antioxidant levels in follicular fluid compared to the two groups taking only folic acid. Conversely, granulosa cells mtDNA content was decreased in treated and higher in untreated obese patients compared to normal-weight women, suggesting mtDNA increases to compensate for oxidative-stress damages. Reduced expression of respiratory subunits in untreated obese may confirm mitochondria impairment. Interestingly, mtDNA levels inversely correlated to both total and metaphase II oocyte number. In this preliminary study, combined supplementation of α-lipoic acid and myo-inositol in infertile obese women was associated with amelioration in the oxidative status of the oocyte environment, possibly contributing to a higher pregnancy rate.