Luteinizing Hormone Activity Research Articles

Safety assessment of three common food additives: the reproductive, oxidative and enzymatic perspective

This investigation was designed to evaluate the reproductive toxicity induced by potassium bromate (at doses of 50, 40, 30, 20, and 10 mg/kg), sodium benzoate (at doses of 5, 4, 3, 2, and 1 mg/kg), and caramel IV (at a dose of 200 mg/kg for 1, 2, 3, 4, and 5 weeks) in male albino mice through the assessments of sperm abnormality and sperm count. The concentrations of the three additives tested were chosen purposefully based on the acceptable daily intake of each of the additives by standard organizations. The level of Total Testosterone (TT), Luteinizing Hormone (LH), and Follicle Stimulating Hormone (FSH), as well as the activities of catalase (CAT), superoxide dismutase (SOD), alkaline phosphatase (ALP), aspartate aminotransferase (AST), and alanine aminotransferase (ALT), were also measured. The results obtained showed that all three tested food additives led to a statistically significant (p < 0.05) increase in abnormal sperm cells among exposed mice. The sperm abnormalities observed include folded sperm, amorphous heads, distal droplets, absent hooks, improper tail attachments, and looped tails. Furthermore, it was observed that only mice exposed to potassium bromate and caramel exhibited a statistically significant decrease in mean sperm count. Alterations in the levels and activities of TT, ALT, FSH, AST, LH, and ALP were also observed to be concentration-dependent in the exposed mice. The findings suggest that the reproductive toxicity and changes in enzyme activities in the treated mice are dependent on the concentration of potassium bromate and sodium benzoate, as well as the duration of exposure to caramel IV. These indicate that high consumption of foods or beverages containing potassium bromate, sodium benzoate, and caramel IV colourant may induce reproductive abnormalities in the consumers.

Combination Therapy with Vitamin D and Metformin: A Potential Approach to Mitigate Testicular Dysfunction in Type 2 Diabetes Mellitus.

Type 2 diabetes mellitus (T2DM) is a multifactorial disease that cannot be linked to a single pathway, causing the observed heterogeneity among T2DM patients. Despite this level of heterogeneity, T2DM is majorly managed by metformin (MET) monotherapy. However, recent findings have associated long-term metformin intake with progressive oxidative pancreatic β cell damage as the disease progresses. Hence, a significant number of patients treated with MET need an alternate therapy. Hence, identifying drug combinations that can effectively alleviate different diabetes complications would serve as a more promising therapy that can translate into active use. Hence, this study was designed to explore the possible synergistic effect of vitamin D and metformin on T2DM-induced testicular dysfunction. Thirty healthy male Wistar rats (weight: 120-150 g and age: 10 ± 2 weeks) were randomly divided into control, diabetes untreated (HFD+STZ), diabetes + vitamin D (1000 IU/kg), diabetes + metformin (180 mg/kg), and diabetes + vitamin D + metformin. All treatments lasted for 28 days and animals were sacrificed using IP injection of ketamine and xylaxine (40 and 4 mg/kg respectively). Vitamin D improved the ameliorative effect of metformin on T2DM-induced hyperglycemia and lipid dysmetabolism, accompanied by a significant decrease in testicular lactate dehydrogenase and lactate. Also, vitamin D + metformin significantly increased serum luteinizing hormone, follicle-stimulating hormone, testosterone, and testicular 5α reductase activities. Furthermore, vitamin D improved the anti-inflammatory and antioxidant effects of metformin by significantly decreasing T2DM-induced increase in testicular interleukin 1beta, interleukin 6, TNF-α, nitric oxide, and NF-κB and increasing T2DM-induced decrease in interleukin 10, glutathione, superoxide dismutase, catalase, GPx, and Nrf2. Vitamin D enhanced the ameliorative effect of metformin on T2DM-induced testicular dysfunction.

Analytical Investigation of the Profile of Human Chorionic Gonadotropin in Highly Purified Human Menopausal Gonadotrophin Preparations.

Highly purified human menopausal gonadotropin (HP-hMG [Menopur®, Ferring Pharmaceuticals, Saint-Prex, Switzerland]) contains a 1:1 ratio of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). This analysis aimed to assess gonadotropin (FSH, LH and hCG) abundance in HP-hMG and clarify the source of hCG by assessing the presence of sulfated glycans, which are diagnostic for pituitary hCG forms due to their distinct glycosylation patterns. Additionally, the purity of each sample, their specific components, and their oxidation levels were assessed. HP-hMG samples (three of Menopur® and two of Menogon® Ferring Pharmaceuticals, Saint-Prex, Switzerland) were included in the current analyses. Brevactid® (urinary hCG; Ferring Pharmaceuticals, Saint-Prex, Switzerland) and Ovidrel® (recombinant hCG; Merck KGaA, Darmstadt, Germany) were used as control samples. Glycopeptide mapping and analysis of impurities were carried out by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Oxidation was assessed through reducing peptide mapping using LC-MS/MS. The FSH and LH in the HP-hMG samples showed sulfated glycans, while no signals of sulfated glycopeptides were detected on any site of the beta subunit of hCG. HP-hMG test samples presented the same hCG glycan distribution as the control sample (placental hCG, Brevactid®) extracted from the urine of pregnant women, suggesting a non-pituitary source of hCG. Protein impurities were estimated to constitute approximately 20-30% of the entire HP-hMG protein content in the test samples. More than 200 non-gonadotropin proteins were identified in the HP-hMG test samples, of which several were involved in embryonic development or pregnancy. The alpha subunit of the tested samples was strongly oxidized, with a relative abundance of 20% of the total gonadotropin content. Without taking into account all the protein impurities, the beta subunit of LH was detected only in traces (0.9-1.2%) in all tested HP-HMG samples, confirming the data obtained by intact molecule analysis, while high levels of beta hCG (18-47%) were observed. Advanced molecular analysis of HP-hMG indicates a primarily placental origin of hCG, as evidenced by the absence of hCG sulfated glycans and the predominance of placental non-sulfated hCG in LH activity. The analysis revealed 20-30% of protein impurities and a significant presence of oxidized forms in the HP-hMG samples. These findings are critical for understanding the quality, safety, and clinical profile of HP-hMG.

Effect of resveratrol on spermatogenesis in breeding boars and the proteomic analysis for testes

Effect of resveratrol (RSV) on spermatogenesis and the mechanism of resveratrol in promoting spermatogenesis of breeding boars was explored by feeding sexually mature Duroc boars with normal diet and 20 mg/kg resveratrol diet for 14 days to the control group and experimental group, respectively. Semen volume, sperm density, motility, viability and abnormality rate were analyzed on day 0, 7, and 14. Blood samples were collected, and levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone (T) in serum were analyzed. On day 14, the testis tissue was collected for antioxidant and proteomics analysis etc. The semen volume, sperm density, motility, and viability of the experimental group and the contents of serum FSH, LH, T and plasma SOD activity were significantly higher than those in the control group. However, the serum IL-6, TNF-α and plasma MDA were remarkably lower in experimental group. The above results showed that resveratrol can simulate spermatogenesis in breeding boars. Proteomic results demonstrated that three differentially expressed proteins (DEPs) were up-regulated and 12 DEPs were down-regulated; ODF1, calmodulin, Cabs1, and Hp were involved in spermatogenesis; and the main enriched metabolic pathway is steroid hormone synthesis pathway. Therefore, the improvement in sperm quality by resveratrol may be achieved by regulating the changes in outer dense fiber 1, calmodulin, spermatid specific 1, and haptoglobin expression and steroid synthesis pathway.

Effect of Adding Luteinizing Hormone (lh) activity during Controlled Ovarian Hyperstim ulation (coh) by adding Human Chorionic Gonadotropin vs. Low Dosage Human Chorionic Gonadotropin on Subsequent Pregnancy Rates Following Frozen Embryo Transfer

Effect of Adding Luteinizing Hormone (lh) activity during Controlled Ovarian Hyperstim ulation (coh) by adding Human Chorionic Gonadotropin vs. Low Dosage Human Chorionic Gonadotropin on Subsequent Pregnancy Rates Following Frozen Embryo Transfer

P-649 Unconventional action of Luteinizing Hormone

Abstract Study question Has Luteinizing Hormone (LH) a role in the activation/survival of follicles of the primary ovarian reserve? Summary answer LH promotes survival and perhaps activation/growth of primordial and primary follicles, proliferation of granulosa cells of secondary follicles, reduces follicle atresia at later growing stages. What is known already In the mammalian ovary, Primordial Follicles (PMFs) constitutes the primary ovarian reserve, which declines over time due to physiological events such as atresia, recruitment, and ovulation. While in the adult, the role of LH in steroidogenesis and ovulation is well established, recent work from our laboratory has shown that under chemotherapeutic treatments, LH supports PMFs survival in prepuberal mouse ovary. Study design, size, duration LH effects on follicle dynamics and some activities of pre-granulosa cells were investigated in vitro and in vivo. In vitroexperiments were performed on PD4 GFP/Kit mice ovarian fragments and on PD8 CD1 mice ovarian somatic cells cultured up to six days in continuous presence of 0.2, 0.5, 1IU LH. In vivo experiments were performed on 9 PD4 and 8 PD28 CD1 mice receiving an intra-peritoneal injection for eight consecutive days of 1-5IU LH. Participants/materials, setting, methods Number and diameters of the GFP stained oocyte were counted in the ovarian fragments. Kit-Ligand and LH-R mRNA expression levels were analyzed by qPCR in pre-granulosa cells. For in vivo experiments, ovarian volume was measured by Micro-Ct and follicle counts were performed on histological sections. Estrous cycle phases were monitored by vaginal smear during the 8 days of treatment. Statistics was performed using Student’s t-test. Main results and the role of chance In fragments of PD4 mouse ovaries cultured in vitro for six days, 1IU LH significantly increased the number of oocytes with a diameter &amp;gt;40 mm (CTRL 17.7% vs LH 36.07%, p &amp;lt; 0,05), suggesting activation of PMFs. Moreover, the hormone increased the expression of mRNA for LHR and KL in the somatic ovarian cells and promoted their proliferation in vitro. The effects of 1IU LH on PD4 females can be summarized as follows: 1. Ovary volume increase (CTRL 0.3 mm3 vs LH 0.36 mm3, p = 0.07), 2. higher percent of PMFs (CTRL 68.227% vs LH 78.29%, p &amp;lt; 0,05) associated with lower percent of primary (CTRL 7.2% vs LH 4.05%, p &amp;lt; 0.04) and growing follicles (CTRL 14.18% vs LH 8.56%, p = 0.1), 3. higher number of granulosa cell layers (&amp;gt; three layers) in secondary follicles (CTRL 42.8% vs LH 54.6%), and 4. lower percent of atretic follicles (CTRL 2.64% vs LH 1.72%, p = 0.1). Similar results were obtained on 28 dpp mice. Morever, we observed that corpora lutea were present only in ovaries of LH-treated females and that all such females were in estrus. Limitations, reasons for caution The study was conducted only in mice. Wider implications of the findings These studies have highlighted new possible roles of LH on follicle classes (primordial/primary) whose development is considered gonadotropin independent. The results, if confirmed in humans, imply that LH might be used as a treatment for patients with ovarian disorders involved the survival/dynamics of the ovarian reserve. Trial registration number NA

O-043 Con

Abstract Dual and/or double trigger improve IVF success - CON The improvement of in vitro fertilization (IVF) outcomes remains a pivotal area of reproductive medicine research, with the dual trigger approach emerging as a significant innovation. This con abstract explores the scientific basis, methodology, and outcomes associated with the dual trigger strategy, juxtaposed with conventional triggering methods in IVF protocols. The dual trigger, incorporating both Gonadotropin-Releasing Hormone Agonist (GnRHa) and Human Chorionic Gonadotropin (hCG), has been posited to improve oocyte maturation, retrieval-, and live birth rates. By scrutinizing recent studies, clinical trials, and meta-analyses, this debate aims to delineate the efficacy, safety, and application scope of this approach. Initial investigations into the dual trigger method have highlighted its potential to ameliorate oocyte quality and maturity, which are crucial determinants of IVF success. The mechanism underlying this improvement involves the simultaneous activation of LH (Luteinizing Hormone) and FSH (Follicle Stimulating Hormone) receptors, enhancing follicular response and oocyte developmental competence. Studies have demonstrated an increase in the number of mature oocytes retrieved, attributed to the more synchronized and comprehensive follicular stimulation afforded by the dual trigger. This augmentation in oocyte quality and quantity directly correlates with enhanced embryo development profiles, and higher implantation and clinical pregnancy rates. Furthermore, the dual trigger method has shown promise in reducing the incidence of Ovarian Hyperstimulation Syndrome (OHSS), a severe complication of IVF treatments. By leveraging the luteolytic effects of GnRHa, this strategy minimizes the risk associated with exogenous hCG administration, thus offering a safer alternative for patients predisposed to OHSS. The application of the dual trigger in specific patient cohorts, such as those with PCOS or poor ovarian responders, has been underlined, indicating its potential for personalized reproductive medicine. However, the implementation of the dual trigger strategy is not without challenges. Variability in patient response necessitates a highly individualized approach, with precise dosing and timing adjustments to optimize outcomes. The existing literature presents a heterogeneity in study designs, populations, and outcome measures, which complicates the direct comparison of dual trigger efficacy against traditional methods. Furthermore, the long-term safety and potential impacts on offspring warrant further investigation, given the recent adoption of this approach. In conclusion, the dual trigger strategy may offer significant benefits in enhancing IVF outcomes. Its potential to improve oocyte maturity and quality could increase the number of retrievable oocytes and reduce the incidence of OHSS. However, it is important to acknowledge that, while the GnRH agonist trigger combined with a freeze-all strategy eliminates the risk of OHSS in women with PCOS, the dual trigger approach followed by fresh embryo transfer does not. Further research is imperative to refine its application, understand its mechanisms fully, and establish comprehensive guidelines for its use. The promise of the dual trigger approach underscores the importance of continuous innovation and evidence-based practices in enhancing the efficacy and safety of IVF treatments.

Health risk and germ cell toxicity of five commercially available sachet waters in Nigeria: a public health concern.

Sachet water is the most common form of portable water commercially available in Nigeria. Using the murine sperm count and sperm abnormality assay, the germ cell toxicity of five common commercially available sachet waters in Nigeria was assessed in this study. The levels of hormones such as Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH) and Total Testosterone (TT); and activities of catalase (CAT), alanine aminotransferase (ALT), superoxide dismutase (SOD), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were evaluated. The heavy metal and physicochemical parameters of the sachet waters were also analyzed. Healthy male mice were allowed to freely drink the sachet waters for 35days after which they were sacrificed. The findings indicated that the concentrations of some heavy metals (As, Cr, and Cd) in the sachet waters exceeded the limit by regulatory organizations. The data of the total carcinogenic risk (TCR) and total non-carcinogenic risk (THQ) of some heavy metals associated with the ingestion of sachet water for adults and children showed that the values exceeded the acceptable threshold, and thus, is indicative of a high non-carcinogenic and carcinogenic risks. The data of the sperm abnormality assay showed that in the exposed mice, the five sachet waters induced a statistically significant (P<0.05) increase in abnormal sperm cells and a significantly lower mean sperm count. Additionally noted were changes in the serum activities of TT, FSH, ALP, AST, ALT, and LH. Thus, the sachet waters studied contained agents that can induce reproductive toxicity in exposed humans. This is of public health importance and calls for immediate action by regulatory bodies.

The beneficial effect of Allium Cepa bulb extract on reproduction of rats; A two-generation study on fecundity and sex hormones.

Allium Cepa Linn. (Onions) has extensively been used in traditional medicine, is one of the important Allium species regularly used in our daily diet, and has been the source of robust phenolic compounds. The current study is intended to evaluate the fecundity-enhancing effect of A. Cepa on the reproductive performance of two successive generations of rats; F0 and F1. A. Cepa extract was initially tested for in vitro antioxidant assay via DPPH and ROS, followed by in vivo toxicity testing. In the fecundity assessment, eighteen pairs of male and female rats (n = 36, 1:1, F0 generation) were divided into three groups and dosed with 75mg/kg and 150 mg/kg daily of A. Cepa extract and saline respectively, up to pre-cohabitation, cohabitation, gestation and lactation period. The reproductive performance, including body weight, live birth index, fertility index, and litter size, was assessed. Various parameters like Hematological, Hormonal (FSH, LH, Testosterone, estradiol), antioxidant markers (SOD, Glutathione peroxidase) and lipid profile of F0 and F1 generations were assessed with evaluation of histopathology of male and female organs. Ethanolic extract of A. Cepa showed the greatest antioxidant potential in DPPH and ROS methods. The continued exposure of the F0 and F1 generations to A. Cepa extract did not affect body weight, fertility index, litter size, and survival index. However, semen pH, sperm motility, sperm count, sperm viability, and semen volume were significantly improved in both generations. We have found pronounced fecundity outcomes in both genders of F0 and F1 generations with A. Cepa 150mg/kg/day extract as compared to control. Results showed that A. Cepa significantly increased (P < 0.05) hemoglobin, follicular stimulating hormone (FSH), luteinizing hormone (LH), plasma testosterone and glutathione peroxidase activities, while total lipid, LDL, and cholesterol were significantly decreased (P < 0.05) in both generations. Histology of both generations of animals reveals enhanced spermatogenesis and enhanced folliculogenesis with improved architecture. Altogether, the present results suggest that A. Cepa extract improved fecundity in both male and female rats by improving hormonal activities and oxidative stress.

HMG addition affects the change in progesterone level during IVF stimulation and LBR: a retrospective cohort study

BackgroundPremature progesterone (P) rise during IVF stimulation reduces endometrial receptivity and is associated with lower pregnancy rates following embryo transfer (ET), which can influence provider recommendation for fresh or frozen ET. This study aimed to determine whether change in P level between in IVF baseline and trigger (\U0001d6abP) is predictive of pregnancy outcome following fresh ET, and whether the ratio of gonadotropins influences P rise and, as a result, clinical pregnancy outcomes: clinical pregnancy rate (CPR) and live birth rates (LBR).MethodsRetrospective cohort study at a single fertility center at an academic institution. The peak P level and \U0001d6abP were modeled in relation to prediction of CPR and LBR, and the ratios of hMG:rFSH were also modeled in relation to prediction of peak P level on day of trigger, \U0001d6abP, and CPR/LBR in a total of 291 patients undergoing fresh embryo transfer after controlled ovarian hyperstimulation-IVF (COH-IVF).Results\U0001d6abP correlates with CPR, with the most predictive range for success as \U0001d6abP 0.7–0.85 ng/mL (p = 0.005, 95% CI 0.635, 3.636; predicting CPR of 88.9%). The optimal range for peak P in regard to pregnancy outcome was 0.15–1.349 ng/mL (p = 0.01; 95% CI for coefficient in model 0.48–3.570). A multivariable logistic model for prediction of CPR and LBR using either peak or \U0001d6abP supported a stronger association between \U0001d6abP and CPR/LBR as compared to peak P. Furthermore, an hMG:rFSH ratio of > 0.6 was predictive of lowest peak P (p = 0.010, 95% CI 0.035, 0.256) and smallest \U0001d6abP (p = 0.012, 95% CI 0.030, 0.243) during COH-IVF cycles. Highest CPRs were observed within hMG:rFSH ratios of 0.3–0.4 [75.6% vs. 62.5% within and outside of the range, respectively, (p = 0.023, 95% CI 0.119, 1.618)]. Highest LBRs were seen within the range of 0.3–0.6 hMG:rFSH, [LBR of 55.4% vs. 41.4% (p = 0.010, 95% CI 0.176, 1.311)].ConclusionsOur data supports use of \U0001d6abP to best predict pregnancy rates and therefore can improve clinical decision making as to when fresh ET is most appropriate. Furthermore, we found optimal gonadotropin ratios can be considered to minimize P rise and to optimize CPR/LBR, emphasizing the importance of luteinizing hormone (LH) activity in COH-IVF cycles.

SAT600 Absent LH Signaling Rescues The Anxiety Phenotype In Aging Female Mice

Abstract Disclosure: S. Sims: None. O. Barak: None. V. Ryu: None. S. Miyashita: None. H.S. Kannangara: None. F. Korkmaz: None. A. Macdonald: None. A. Gumerova: None. K. Goosens: None. M. Zaidi: None. T. Yuen: None. D. Lizneva: None. T. Frolinger: None. Clinical studies and experimental data together support a role for pituitary gonadotropins, including luteinizing hormone (LH), otherwise considered solely as a fertility hormones, in age-related cognitive decline. Furthermore, rising levels of LH in post-menopausal women have been implicated in the high prevalence of mood disorders. This study was designed to examine the effect of deficient LH signaling, using the global Lhcgr-/- mouse, on both cognitive and emotional behavior in 12-month-old mice. For this, we established and validated a battery of five tests, including Dark-Light Box (DLB), Y-Maze Spontaneous Alternation, Novel Object Recognition (NOR) and contextual and cued Fear Conditioning (FCT) tests. We found that 12-month-old female mice display a prominent anxiety phenotype on DLB and FCT. This phenotype was not seen in female Lhcgr-/- mice, indicating full phenotypic rescue. Furthermore, there was no effect of depleting LHCGRs on recognition memory or working spatial memory on NOR and Y-maze testing, respectively, in 12-month-old mice, notwithstanding the absence of a basal phenotype in wild type littermates. The latter data do not exclude an effect of LH on cognition documented in previous studies. Finally, male mice and 3-month-old male and female mice did not consistently display deficits on any test. The data collectively document, for the first time, that loss of LH signaling reverses age-related emotional disturbances, a prelude to future targeted therapies that block LH action. Presentation: Saturday, June 17, 2023

The protective effect of hydroalcoholic extract of Ephedra pachyclada leaves on ovarian damage induced by cyclophosphamide in rat: An experimental study.

Cyclophosphamide (CP) is an anticancer drug that acts as an alkylation agent after metabolism in the liver. CP has toxic effects on the body's cells, especially the reproductive system's function, and causes infertility. Moreover, medicinal plants have few side effects and are psychologically acceptable to patients. This study aimed to investigate the impact of Ephedra pachyclada hydroalcoholic extract (EPHE) on ovarian tissue and hypothalamic-pituitary-gonadal axis in rats treated with CP. In this experimental study, 48 adult female Wistar rats (180-200 gr, 9-10 wk) were randomly assigned to 6 experimental groups (n = 8/each): (a) control; (b) sham; (c) CP; (d) CP+250 mg/kg EPHE; (e) CP+500 mg/kg EPHE; (f) CP+1000 mg/kg EPHE. On the 29 day of the experiment, serum was collected; serum concentration of the luteinizing hormone, follicle-stimulating hormone, estrogen, progesterone, and antioxidant activity were measured. The number of ovarian follicles were also counted. In the CP groups, serum concentrations of follicle-stimulating hormone and luteinizing hormone significantly increased, and estrogen and progesterone significantly decreased (p 0.05). EPHE significantly compensated for the complications caused by CP and 1000 mg/kg had the greatest effect. Antioxidant reduction by CP was significantly enhanced by EPHE, especially at higher doses (p 0.05). The number of primordial, primary, secondary, and Graafian follicles showed a significant decrease in CP groups and EPHE groups showed a significant increase compared to the CP. EPHE showed that the concentration of 1000 mg/kg was more effective than other doses (p 0.05). In addition to proving the effect of EPHE on the hypothalamic-pituitary-gonadal axis, our investigation showed antioxidant properties, which can be an effective factor in CP-treated rats.

Absent LH signaling rescues the anxiety phenotype in aging female mice.

Clinical studies and experimental data together support a role for pituitary gonadotropins, including luteinizing hormone (LH), otherwise considered solely as fertility hormones, in age-related cognitive decline. Furthermore, rising levels of LH in post-menopausal women have been implicated in the high prevalence of mood disorders. This study was designed to examine the effect of deficient LH signaling on both cognitive and emotional behavior in 12-month-old Lhcgr-/- mice. For this, we established and validated a battery of five tests, including Dark-Light Box (DLB), Y-Maze Spontaneous Alternation, Novel Object Recognition (NOR), and contextual and cued Fear Conditioning (FCT) tests. We found that 12-month-old female wild type mice display a prominent anxiety phenotype on DLB and FCT. This phenotype was not seen in 12-month-old female Lhcgr-/- mice, indicating full phenotypic rescue. Furthermore, there was no effect of LHCGR depletion on recognition memory or working spatial memory on NOR and Y-maze testing, respectively, in 12-month-old mice, notwithstanding the absence of a basal phenotype in wild type littermates. The latter data do not exclude an effect of LH on cognition documented in previous studies. Finally, 12-month-old male mice and 3-month-old male and female mice did not consistently display deficits on any test. The data collectively document, for the first time, that loss of LH signaling reverses age-related emotional disturbances, a prelude to future targeted therapies that block LH action.

Dosing Characteristics of Recombinant Human Luteinizing Hormone or Human Menopausal Gonadotrophin-Derived LH Activity in Patients Undergoing Ovarian Stimulation: A German Fertility Database Study

Objectives: The aim of the study was to evaluate dosing of recombinant human luteinizing hormone (r-hLH) or human menopausal gonadotrophin (hMG)-derived medications with LH activity in ovarian stimulation (OS) cycles for in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI). Design: A non-interventional study was performed to analyse data from the German RecDate database (January 2007–December 2011). Participants/Materials, Setting, Methods: Starting/total r-hLH/hMG dose, OS duration/cycle number, r-hLH/hMG initiation day (first day of administration), and population/cycle characteristics were assessed in women (≥18 years) undergoing OS for IVF/ICSI using r-hLH or hMG-derived medications (excluding corifollitropin alfa, clomiphene citrate, letrozole, mini/micro-dose human chorionic gonadotrophin, and urofollitropin alone). Data were summarized descriptively. Results: 67,858 identified cycles utilized medications containing r-hLH (10,749), hMG (56,432), or both (677). Mean (standard deviation) OS duration with r-hLH and hMG was 10.1 (4.43) and 9.8 (6.16) days, respectively. Median (25th–75th percentile) r-hLH starting dose (75.0 [75.0–150.0] IU) was consistent across patients regardless of age, infertility diagnosis, or gonadotrophin-releasing hormone (GnRH) protocol. Median (25th–75th percentile) hMG-derived LH activity starting dose was 225.0 (150.0–300.0) IU, regardless of GnRH protocol, but was lower in women aged <35 years and those with ovulation disorders/polycystic ovary syndrome. Median (25th–75th percentile) total dose for r-hLH (750.0 [337.5–1,125.0] IU) and hMG-derived LH activity (1,575.0 [750.0–2,625.0] IU) varied according to patients’ age, infertility diagnosis, cycle number, and r-hLH/hMG initiation day. GnRH antagonist use resulted in a numerically higher median total hMG-derived LH activity dose than GnRH agonist use. Limitations: The data used in this study were taken from electronic medical records relating to a specific timeframe (2007–2011) and therefore may not accurately reflect current clinical practice; however, it is likely that the differences between the two compounds would be maintained. Additionally, secondary data sources may suffer from uniformity and quality issues. Conclusions: The standard of care for OS cycles is described with respect to IVF/ICSI treatment including an LH component in Germany during the specified timeframe.

P-639 Are our advanced maternal age population being affected by the shortage of HP-hMG?

Abstract Study question Could we stimulate patients of advanced maternal age in the face of a shortage of HP-hMG without impacting outcomes? Summary answer Given the current low availability of HP-hMG, it is safe to stimulate only with recombinant FSH in women of advanced maternal age without affecting results. What is known already . Studies on the role of luteinizing hormone (LH) supplementation in patients undergoing assisted reproductive treatments use different sources of LH bioactivity. It is well known that the addition of LH supplementation was associated with a tendency towards improved IVF outcome in specific profiles of patients undergoing Assisted Reproductive treatment. However, during the last quarter of 2022, we are facing a temporary fall in the global supply of HP-hMG, which has hCG-driven LH activity, and may impact ovarian stimulation outcomes in women of advanced maternal age undergoing a preimplantation genetic testing treatment (PGT). Study design, size, duration Retrospective and observational study during November-December 2022 in any of the 11 clinics belonging to the IVIRMA group in Spain. Study population included women ≥38 years undergoing PGT treatment who received monotherapy with recombinant FSH (n = 73), a combination of FSH + HMG containing an FSH: LH activity in a ratio 1:1 (n = 103), or a fertility drug with recombinant FSH + recombinant LH in a 2:1 ratio (n = 112). The study was approved by an IRB (2003-MAD-020-AR) Participants/materials, setting, methods All women underwent short GnRH antagonist protocol. Initial doses were adjusted based on weight and body mass index according to the clinician’s experience. Daily doses of 0.25 mg GnRH antagonist were started on day 6 of stimulation. Finally, a single dose of 0.2 mg GnRH agonist was administered to trigger final oocyte maturation. Embryo biopsy was performed on day 5 with a subsequent freeze-all. A frozen single embryo transfer was accomplished in a subsequent cycle. Main results and the role of chance Assuming the limitations of the study design, we observed significant differences in gonadotropin doses but not in retrieved oocytes, metaphase II oocytes or euploidy rate: the results were as follows for recombinant FSH, FHS + hMG and FSH + LH respectively: gonadotropin doses [2254 (692) vs. 2033 (680) vs. 2000 (660), p = 0.0035]; retrieved oocytes [10.1 (5.4) vs. 11.1 (8.0) vs. 9.2 (6.0), p = 0.131], metaphase II oocytes [8.7 (4.7) vs. 9.8 (7.1) vs. 8.3 (5.1), p = 0.147]; and euploidy rate (38.7% vs. 36.3% vs. 31.5%, p = 0.182). Moreover, recombinant FSH in monotherapy in this specific population could guarantee the efficiency of the cycle since there are no significant differences in the usable blastocyst rate. Finally, clinical results were analyzed in those cases in which a frozen single embryo had been performed in a subsequent artificial cycle, in which the effect of LH on the endometrium is obviated; once again, no significant differences were observed between the study groups neither for the implantation rate (50% vs. 56% vs. 45%, p = 0.780) or the clinical pregnancy rate (50% vs. 56% vs. 45%, p = 0.772). Limitations, reasons for caution This is a retrospective and observational study and thus possible confounders cannot be completely excluded. More data are needed to draw firm conclusions and it will be critical to increase the sample size to check if the results observed in this work remains in the general population. Wider implications of the findings In view of tailoring assisted reproductive protocols to meet patient needs and improve the likelihood of positive outcomes, these data suggest that it is optimal to perform an ovarian stimulation protocol only with recombinant FSH in a frozen embryo program in advanced maternal age context without clinical outcomes being affected. Trial registration number Not applicable

The modulator role of Urtica dioica on deleterious effects of retinoic acid high doses on histological parameters and fertilization of rats

AimThis study purposed to evaluate the modulator and protective role of Urtica dioica (UD) extract against deleterious effects of retinoic acid (RA) high doses on histological parameters and fertilization of rats. Materials and methodsFor the in-vivo phase, 60 female Wistar rats were divided into 6 identical groups as 1) control, 2) 25 mg/kg RA, 3) 25 mg/kg UD extract, 4) 50 mg/kg UD extract, 5) UD extract (25 mg/kg) + RA (25 mg/kg), and 6) UD extract (50 mg/kg) + RA (25 mg/kg). Biochemical parameters, including luteinizing hormone (LH), folliclestimulating hormone (FSH), malondialdehyde (MDA) levels, superoxide dismutase (SOD), and catalase (CAT) activities, were measured. In the in-vitro phase, oocytes were obtained from 10 female rats without injection. In addition to the mentioned parameters, histological parameters (oocytes in various stages) and the results of IVM, IVF, and embryo developments were assessed and compared among the groups with the use of one-way ANOVA and Tukey's post hoc tests. ResultsThe high dosage of RA significantly reduced the LH and FSH levels; however, UD alone and with RA increased the hormone levels in rats. Regarding the reactive oxygen species (ROS) activity levels in rats' blood samples, RA increased the MDA and decreased the SOD and CAT levels. Treatment with UD extract (UD + RA groups) significantly improved the parameters mentioned, showing UD's antioxidant effect. The rate of oocyte maturation, 2-cell–4-cell and 4-cell–8-cell embryos, and blastocyst formation increased significantly in the groups in which UD extracts were administered compared to the control and RA groups. Furthermore, the increases were significant in the UD + RA groups compared to the RA group. ConclusionUD extract can significantly reduce RA high doses side effects on histological parameters and fertilization of rats and has the protective potential against RA deleterious effects.

Effect of follicle-stimulating hormone and luteinizing hormone levels on egg-laying frequency in hens.

Gonadotropins, for example, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), are hormones that affect the reproductive process. In hens, optimal levels of FSH and LH can stimulate follicle growth fairly rapidly and thereby increase egg production through follicle development and increased ovulation. Follicle-stimulating hormone acts in the early stages of follicular growth, whereas LH acts on pre-ovulatory follicles. Normal follicular growth is the result of the complementary action of FSH and LH. Low FSH and LH levels result in the formation of follicles but a lack of egg production in chickens. This study aimed to investigate FSH and LH hormone levels from layer chickens with different egg-laying frequencies. Fifty blood serum samples were collected from 54-week-old ISA brown strain hens that were divided into five groups (with 10 hens per group) as follows: Hens that lay eggs (i) every day, (ii) once every 2 days, (iii) twice every 3 days, (iv) 3 times every 4 days, and (v) hens that do not lay eggs. Follicle-stimulating hormone and LH levels were measured in samples using an enzyme-linked immunosorbent assay, and the data were analyzed using multivariate analysis of variance. Follicle-stimulating hormone levels were significantly associated with the frequency of egg laying in ISA brown strain hens (p < 0.05); the highest FSH level (869.005 ± 149.194 pg/mL) was found in hens that lay eggs every day. In contrast, the highest LH level (51.386 ± 2.410 mIU/mL) was found in hens that lay eggs every 2 days. High level of FSH (869.005 ± 149.194 pg/mL) was associated with a high frequency of egg laying (every day) in ISA brown strain hens, and LH level of around 30.406 pg/mL was associated with daily egg laying in these hens.

Gonadotropin releasing hormone analogs as part of controlled ovarian stimulation

I describe how we identified the need to block the luteinizing hormone (LH) surge when trying to control the processes of luteinization and ovulation within the clinic. The first step, in fact, was using ovarian ultrasound evaluation of follicular development in the natural cycle (published in 1979) and then when the ovary was stimulated with exogenous follicle stimulating hormone. We observed that induced multiple follicular development often led to "premature" LH surges-which occurred before the leading follicle had achieved normal preovulatory dimensions. The work required both ovarian ultrasound and reliable radioimmunoassays, which were not always available. When early work with gonadotropin releasing hormone agonists showed that they could suppress LH activity, it was the logical step to try to use them to perform that task during the induction of multiple follicular development. High frequency administration of the gonadotropin releasing hormone-agonist successfully achieved sustained LH suppression through the follicular phase allowing clinical control of luteinization and ovulation.

Sex-specific responses to growth hormone and luteinizing hormone in a model teleost, the Mozambique tilapia

Across the vertebrate lineage, sexual dimorphism in body size is a common phenomenon that results from trade-offs between growth and reproduction. To address how key hormones that regulate growth and reproduction interact in teleost fishes, we studied Mozambique tilapia (Oreochromis mossambicus) to determine whether the activities of luteinizing hormone (Lh) are modulated by growth hormone (Gh), and conversely, whether targets of Gh are affected by the presence of Lh. In particular, we examined how gonadal morphology and specific gene transcripts responded to ovine GH (oGH) and/or LH (oLH) in hypophysectomized male and female tilapia. Hypophysectomized females exhibited a diminished gonadosomatic index (GSI) concomitant with ovarian follicular atresia. The combination of oGH and oLH restored GSI and ovarian morphology to conditions observed in sham-operated controls. A similar pattern was observed for GSI in males. In control fish, gonadal gh receptor (ghr2) and estrogen receptor β (erβ) expression was higher in females versus males. A combination of oGH and oLH restored erβ and arβ in females. In males, testicular insulin-like growth factor 3 (igf3) expression was reduced following hypophysectomy and subsequently restored to control levels by either oGH or oLH. By contrast, the combination of both hormones was required to recover ovarian igf3 expression in females. In muscle, ghr2 expression was more responsive to oGH in males versus females. In the liver of hypophysectomized males, igf2 expression was diminished by both oGH and oLH; there was no effect of hypophysectomy, oGH, or oLH on igf2 expression in females. Collectively, our results indicate that gene transcripts associated with growth and reproduction exhibit sex-specific responses to oGH and oLH. These responses reflect, at least in part, how hormones mediate trade-offs between growth and reproduction, and thus sexual dimorphism, in teleost fishes.

Luteinizing Hormone and Ovarian Stimulation for In-Vitro Fertilization: Do Science and Business Always Agree?

The current commentary paper follows the historical introduction of gonadotropins and gonadotropin releasing hormone (GnRH) analogues to the in-vitro fertilization (IVF) market. We maintain that business decisions significantly influenced research and development; however, pharma decisions did not always align with physiology and clinical interests. Specifically, the never-ending debate on the issue of luteinizing hormone (LH) supplementation during ovarian stimulation was repeatedly studied using population-based randomized controlled trials. However, LH activity supplementation is an endocrine issue and therefore, specific endocrine inclusion/exclusion criteria should be used when assessing the needs or not for LH in our “every-day” patients. We propose that the approach until now has defocused the research question and thus, also the debate and that there is a need to revisit physiology and clinical thinking if the LH supplementation issue is to be unravelled.