The effects of purslane (Portulaca oleracea) and fennel (Foeniculum vulgare Mill) hydroalcoholic extracts on the functional parameters of human spermatozoa after vitrification

OBJECTIVE

Reactive oxygen species (ROS) are produced during cryopreservation of human sperm and impair sperm function. Antioxidant compounds, such as fennel and purslane, reduce the damaging effects of ROS. This study aimed to evaluate motility parameters, plasma membrane integrity (PMI), mitochondrial membrane potential (MMP), intracellular ROS, and DNA damage to determine the optimum concentrations of hydroalcoholic extracts of fennel and purslane for human spermatozoa cryopreservation.

METHODS

Twenty human sperm samples were used and divided into seven equal groups consisting of fennel hydroalcoholic extract (5, 10, and 15 mg/L), purslane hydroalcoholic extract (25, 50, and 100 mg/L), and no additive.

RESULTS

Supplementation of 25 mg/L and 50 mg/L purslane extract and 10 mg/L fennel extract in cryopreservation extender significantly increased the motility and PMI of sperm with a significant reduction in intracellular ROS compared to control groups (p<0.05). A 50 mg/L concentration of purslane extract elevated progressive motility and MMP compared to the control group (p<0.05). No significant differences were seen for motion patterns and DNA damage of frozen-thawed human sperm in extender containing these extracts.

CONCLUSION

The results showed that supplementation of 50 mg/L purslane extract and 10 mg/L fennel extract in semen cryopreservation extender has the potential to decrease intracellular ROS and subsequently elevate the motility and PMI of human sperm.

Use of cryoprotectors and antioxidants in sturgeon semen cryopreservation

In recent years, the possibility of increasing the low cryoresistance of sturgeon sperm by using antioxidants in basic cryoprotective media has been studied. The goal of this work was to review the current literature on impact of the cryoprotectors, well-known antioxidants and new multifunctional compounds on the activity indicators and fertilizing capability of sperm, as well as on biomarkers of cryostress. A special attention is given to the radical scavenging activity of studied compounds in relation to the highly reactive oxygen species, to prevent and negate oxidative stress damage of sturgeon sperm. Also, new trends for future research through the application of novel polyfunctional antioxidants to sturgeon sperm cryopreservation were indicated.

Addition of orange, pineapple and beet juices as extenders for cryopreservation of ram semen

Abstract Searching for improvements in semen cryopreservation, natural substances are commonly studied focusing to improve the sperm quality. The aim of this study were evaluated the effect of adding orange, pineapple, and beet juices in different concentrations and combinations to the ram semen cryopreservation extender. Five ejaculates from five adult rams were used. The semen pool was diluted in egg yolk-based extender and mixed with the following 15 treatments (at a final concentration of 400.106 sptz/mL): orange 10% (O10) and 15% (O15); pineapple 10% (P10) and 15% (P15); beet 10% (B10) and 15% (B15); pineapple + orange 10% (PO10) and 15% (PO15); pineapple + beet 10% (PB10) and 15% (PB15); beet + orange 10% (BO10) and 15% (BO15); pineapple + beet + orange 10% (PBO10) and 15% (PBO15); and the control group (CON). Post-thaw in 0.25 mL straws semen quality analysis of cryopreserved semen was performed by CASA and flow cytometry. Analysis of variance (PROC GLM) was carried out and the averages were compared using the SNK test. Pearson's correlation test was also performed. No effect was noted in the addition of juices to the semen extender prior to cryopreservation. Post-thawed, although, statistically similar to the control group, the total motility of the B10 group reached acceptable standards of total motility. In addition, B10 group showed the highest values (p<0.05) of progressive motility than control group or other treatments. The addition of 10% beet juice to the ram semen extender can improve the cryopreservation of sperm motility.

Adição de sucos de laranja, abacaxi e beterraba em diluidor para criopreservação de sêmen de carneiros

Resumo Em busca de melhorias na criopreservação do sêmen, substâncias naturais são comumente estudadas com o objetivo de melhorar a qualidade do sêmen. O objetivo deste estudo foi avaliar o efeito da adição de sucos de laranja, abacaxi e beterraba em diferentes concentrações e combinações ao diluidor de criopreservação de sêmen ovino. Foram utilizados cinco ejaculados de cinco carneiros adultos. O pool de sêmen foi diluído em diluente à base de gema de ovo e misturado com os seguintes 15 tratamentos (na concentração final de 400x10⁶ sptz/ml): laranja 10% (O10) e 15% (O15); abacaxi 10% (P10) e 15% (P15); beterraba 10% (B10) e 15% (B15); abacaxi + laranja 10% (PO10) e 15% (PO15); abacaxi + beterraba 10% (PB10) e 15% (PB15); beterraba + laranja 10% (BO10) e 15% (BO15); abacaxi + beterraba + laranja 10% (PBO10) e 15% (PBO15); e o grupo controle (CON). Pós-descongelação em palhetas de 0,25 ml a análise da qualidade do sêmen criopreservado foi realizada pelo CASA e citometria de fluxo. A análise de variância foi realizada e as médias comparadas pelo teste SNK. O teste de correlação de Pearson também foi realizado. Nenhum efeito foi observado na adição de sucos ao diluidor de sêmen antes da criopreservação. Após o descongelamento, embora estatisticamente semelhante ao grupo controle, a motilidade total do grupo B10 atingiu padrões aceitáveis de motilidade total. Além disso, o grupo B10 apresentou os maiores valores (p<0,05) de motilidade progressiva que o grupo controle ou os outros tratamentos. A adição de 10% de suco de beterraba ao diluente de sêmen ovino pode melhorar a criopreservação da motilidade espermática.

Role of exogenous antioxidants on the performance and function of pig sperm after preservation in liquid and frozen states: A systematic review

In situations where an excessive generation of reactive oxygen species overwhelms antioxidant capacity, a harmful effect on sperm function is exerted. Antioxidants are molecules capable of minimizing this detrimental effect, which is important in pig sperm due to the high content of polyunsaturated fatty acids in their plasma membrane. The present systematic review aims at evaluating whether supplementing semen extenders (for liquid storage at 17 °C) or freezing and/or thawing media (for cryopreservation) with antioxidants influences sperm quality and functionality parameters, and in vitro/in vivo fertility outcomes. We defined inclusion and exclusion criteria in a PICOS table according to PRISMA guidelines, and conducted a literature search through MEDLINE-PubMed in November 2020. After systematic selection, 75 studies were included: 47 focused on cryopreservation and 28 on liquid storage at 17 °C. More than 70% of the studies included in this review showed that adding semen extenders for liquid storage and/or freezing/thawing media for cryopreservation with antioxidants enhances sperm quality and functionality parameters. In addition, this supplementation improves in vivo/in vitro fertility outcomes, supporting the hypothesis that the beneficial effect observed upon sperm quality has a positive impact on reproduction outcomes.

Plant Extracts as Alternative Additives for Sperm Preservation

Sperm preservation is a crucial factor for the success of assisted reproductive technology (ART) in humans, livestock, and wildlife. Irrespective of the extender and the storage conditions used, semen handling and preservation negatively affect sperm quality. Moreover, oxidative stress, which often arises during semen storage, significantly reduces sperm function and compromises the sperm fertilizing ability by inducing oxidative damage to proteins, lipids, and nucleic acids. Plant extracts have recently emerged as a cheap and natural source of additives to preserve and enhance sperm function during semen storage. The present work provides an update on the use of these natural compounds as alternative additives for sperm preservation in 13 animal species, including humans. A detailed description of the effects of 45 plant species, belonging to 28 families, on sperm function during semen storage is presented. The plant material and extraction method employed, dosage, possible toxic effects, and antimicrobial properties are provided.

Antioxidants and their effect on the oxidative/nitrosative stress of frozen-thawed boar sperm

In swine, the use of frozen-thawed boar sperm for artificial insemination remains a suboptimal reproductive technology. Among the negative effects of cryopreservation on sperm cells, it is worth highlighting that cryopreservation causes irreversible alterations in motility and components of the sperm membrane as a result of dramatic changes in temperature (cooling/freezing curve) and osmolality. In addition, freeze-thawing may induce oxidative stress and increase the generation of reactive oxygen species (ROS) and nitrogen reactive species (RNS). While boar sperm cryopreservation has been reported to increase lipid peroxidation and the intracellular levels of hydrogen peroxide, less research on its impact on RNS has been conducted. Furthermore, previous studies have investigated the effects of supplementing cryopreservation media with antioxidants to counteract the deleterious effects of ROS and RNS. Antioxidants of synthetic origin or natural extracts have been used, with some showing noticeable and positive effects on functional sperm parameters both in vitro and in vivo. The aim of this review is to provide an update on the effect of different molecules with antioxidant capacity on the function of cryopreserved boar sperm.

Hydroalcoholic extract and seed of Foeniculum vulgare improve folliculogenesis and total antioxidant capacity level in F1 female mice offspring

Background

Foeniculum vulgare (fennel) is traditionally suggested for the fertility improvement in Iranian lore due to its antioxidant and phytoestrogen compounds. The present study aimed to investigate the effects of fennel seed and its hydroalcoholic extract on the serum total antioxidant capacity (TAC) and folliculogenesis in offspring exposed to either of the treatments in utero and 56 days after birth (PND 56).

Methods

Pregnant NMRI mice were randomly divided into 5 groups of 7: extract-treated groups received 500 and 1000 mg/kg/day fennel extract (FE), seed-treated groups received 500 and 1000 mg/kg/day fennel seed (FS), and the control group (CTL) received no treatment. The treatments started from pregnancy day 1 and continued until PND 56. Body and right ovary weights and ovary dimensions were recorded. Hematoxylin and eosin stained ovary sections were prepared to calculate the proportion of different follicles. The level of TAC in the serums was also measured by fluorescence recovery after photo bleaching.

Results

A marked rise in the body and ovary weights of treated mice was observed compared to the CTL group. The mean number of primordial, primary, pre-antral, and pre-ovulatory follicles as well as corpus luteum size in the treated offspring was significantly higher compared to those of CTL offspring. The atretic follicle number was nonsignificantly lower in either of the treatment groups compared with that in the CTL. However, treatment of animals with 500 mg/kg FE showed a more pronounced effect. Animals in FS500, FE500 and FE1000 groups had a significantly higher level of serum TAC compared to the CTL group.

Conclusions

Fennel extract and seed administration in pregnancy and lactation period improve offspring’s folliculogenesis. Higher level of TAC in the serum of offspring might have positively altered the folliculogenesis milieu.

The effect of astaxanthin supplementation on the post-thaw quality of dog semen

Astaxanthin is a member of the carotenoid family well known for its anti-cancer, anti-diabetic, anti-inflammatory and antioxidant nature. This study was designed to investigate the effects of astaxanthin supplementation of the extender (buffer 2) on post-thaw dog semen quality. Semen from four healthy dogs was collected by digital manipulation twice a week. The ejaculates were pooled, washed, divided into four equal aliquots, diluted with the extender supplemented with different concentrations of astaxanthin (0, 0.5, 1 and 2 µM) and cryopreserved. The results showed that 1 µM astaxanthin was the optimum concentration that led to significantly higher (p < .05) post-thaw motility, kinematic parameters and viability than the other groups. In comparison with the control group, sperm samples supplemented with 1 µM astaxanthin showed significantly higher (p < .05) sperm counts with intact membranes (55.7 ± 0.6% vs. 51.3 ± 0.9%), intact acrosome (58.4 ± 0.7% vs. 53.5 ± 0.6%), active mitochondria (54.9 ± 0.5% vs. 42.6 ± 0.6%) and normal chromatin (67.6 ± 0.9% vs. 61.7 ± 0.6%). Furthermore, astaxanthin-supplemented samples showed significantly lower expression levels (p < .05) of pro-apoptotic (BAX), oxidative induced DNA damage repair (OGG1), oxidative stress-related (ROMO1) genes and higher expression levels of anti-apoptotic (BCL2), and sperm acrosome-associated (SPACA3) genes compared to the control. Thus, supplementation of 1 µM astaxanthin in semen extender results in improved freeze-thaw sperm quality of the dog.

DNA damaging effect of paclitaxel in the epididymal sperms as a chemotherapeutic agent and possible remedies to prevent this effect: A study on reproductive potential of male cancer patients of reproductive age

Cancer is a major public health problem, young cancer patients therefore undergo chemotherapy, and most of them may lose their fertility. DNA damage level provides important clues about the quality and reproductive potential of spermatozoa. In this study, we evaluated the levels of both DNA fragmentation and abnormal DNA integrity in the epididymal sperms of New Zealand rabbit (Oryctolagus cuniculus) after cryopreservation using the terminal deoxyribonucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) assay and the toluidine blue (TB) staining methods and assessed the effects of paclitaxel, resveratrol, l-glutamine (LG), and basal medium eagle (BME) solution on DNA damage. Paclitaxel induced the levels of both DNA damages in the sperms, but resveratrol ameliorated this effect. LG and BME supplementation to the extender prevented the sperm samples from DNA fragmentation after cryopreservation. Chemotherapy drugs containing paclitaxel can cause the sperm DNA to be damaged, and hence adversely affect the fertility of male cancer patients of reproductive age. The administration of resveratrol together with paclitaxel may ameliorate the DNA damage inducing effect of paclitaxel. Sperm banking and cryopreservation with the appropriate cryoprotectants such as LG and BME prior to cancer treatment can also be suggested to all male cancer patients of reproductive age facing cancer treatment for fertility preservation.

Does fennel extract ameliorate oxidative stress frozen-thawed ram sperm?

The aim of this study was to evaluate the quality of ram semen after cryopreservation with different levels of fennel (Foeniculum vulgare) extract (0 (F0), 5 (F5), 10 (F10) and 15 (F15) mg/L) and sperm concentrations (200 (C200) and 400 (C400) × 10⁶ sperm/mL) in a soy lecithin (SL)-based extender. Twenty ejaculates were collected from four ghezel rams and diluted with eight sperm concentrations/fennel combinations: F0C200, F5C200, F10C200, F15C200, F0C400, F5C400, F10C400 and F15C400. Sperm motility, abnormality, plasma membrane, viability, mitochondrial activity, lipid peroxidation (LPO), mitochondrial activity and apoptotic changes were evaluated after freeze-thawing process. It was observed that F10C400 significantly improved total and progressive motility, VSL, membrane integrity of post-thawed ram sperm. MDA level was lower in F5C200 and F10C400 compared to other treatments. The higher percentage of live sperm and the lower percentage of apoptotic sperm were obtained in F10C200 compared to F0C200, F5C200 F15C400, F0C400, F5C400 and F15C400. Extender F10C200 resulted in the highest mitochondria activity compared to the rest of the extenders except F10C400. We conclude that a combination of 10 mg/mL fennel (Foeniculum vulgare) extract and sperm concentration of 200 × 10⁶ sperm/mL can improve the ram semen quality cryopreserved in a soybean lecithin based extender.

Polyphenolics from Albizia harveyi Exhibit Antioxidant Activities and Counteract Oxidative Damage and Ultra-Structural Changes of Cryopreserved Bull Semen

Albizia harveyi is a tropical deciduous tree, found across South and Eastern Africa and widely used in traditional medicine. The leaf extract ameliorated the damaging effects of the frozen-thawing process in cryopreserved bull semen. In a dose-dependent pattern, sperm motility, viability, and membrane integrity were improved compared to the untreated control. Furthermore, the extract increased the percentage of viable sperm cells and reduced the percentages of early apoptotic and apoptotic sperm cells as well as the damage in sperm ultra-structure. These activities are in agreement with the robust antioxidant properties in vitro and in the seminal fluid as observed in the total antioxidant capacity and the lipid peroxidation parameter malondialdehyde. LC-MS yielded 35 compounds. The extract was dominated by quercetin-O-galloyl-hexoside and quercetin-O-pentoside, along with other flavonoid glycosides. The polyphenols are probably responsible for the observed activities. In conclusion, the current findings show that A. harveyi leaves are rich in bioactive polyphenols with functional properties, validating its traditional use.

Treatment of Recurrent Ovarian Cysts and Primary Infertility by Iranian Traditional Medicine: A Case Report

Infertility is a medical and psychosocial problem with a high prevalence. There are different treatments for this problem in Iranian traditional medicine. A 28-year-old woman presented with the complaints of 4 emergency operations of the left ovarian cyst during 4 years and infertility. Diagnostic laparoscopy showed an ovarian cyst, adhesion, and endometriosis. Hysteroscopy was unremarkable. After 2 months of letrozole administration, the ovarian cyst ruptured again. Considering the failure of conventional treatments, Iranian traditional medicine products were administered to the patient. After 3 months, the patient conceived and delivered a healthy boy through normal vaginal delivery. These compounds may help with pregnancy as a uterine tonic, vitalizer, and aphrodisiac with brain and cardiac tonic properties.

The Fertility of Frozen Boar Sperm When used for Artificial Insemination

One of the limits to practical use of frozen boar sperm involves the lowered fertility when used for artificial insemination. Years of studies have shown that 5-6 billion sperm (approximately 3 billion viable) used in single or multiple inseminations results in pregnancy rates most often between 60 and 70% and with litter sizes between nine and 10 pigs. Yet today, it is not uncommon for studies to report pregnancy rates from 70 to 85% and litter sizes with 11-12 pigs. While global statements about the incidence and reasons for higher fertility are not conclusive, incremental fertility improvements appear independently associated with use of a minimum number of viable sperm (1-2 billion), insemination timing that increases the probability that sperm will be present close to ovulation for groups of females, selection for boar sperm survival following cryopreservation, and modification of the freeze and thaw conditions using additives to protect sperm from oxidative damage. Studies show that techniques such as intrauterine and deep uterine insemination can provide an opportunity to reduce sperm numbers and that control of time of ovulation in groups of females can reduce the need for multiple inseminations and improve the chance for AI close to ovulation. However, optimal and consistent fertility with cryopreserved boar sperm may require a multifaceted approach that includes boar selection and screening, strategic use of additives during the freezing and thawing process, post-thaw evaluation of sperm and adjustments in sperm numbers for AI, assessment of female fertility and ovulation induction for single insemination. These sequenced procedures should be developed and incorporated into a quality control system for improved fertility when using minimal numbers of cryopreserved boar sperm.

Recent Advances in Boar Sperm Cryopreservation: State of the Art and Current Perspectives

While sperm cryopreservation is the best technology to store boar semen for long-term periods, only 1% of all artificial inseminations (AI) conducted worldwide are made using frozen-thawed boar sperm. With the emergence of long-term extenders for liquid storage, the use of cryopreserved sperm in routine AI is less required. However, banks of boar semen contain cryopreserved sperm and planning inseminations in AI centres may benefit from the use of frozen-thawed semen. Therefore, there is an interest in the use of this technology to preserve boar sperm. In this regard, although the first attempts to cryopreserve boar semen date back to the seventies and this technology is still considered as optimal, some relevant improvements have been made in the last decade. After giving a general picture about boar sperm cryodamage, the present review seeks to shed light on these recent cryopreservation advances. These contributions regard to protein markers for predicting ejaculate freezability, sperm selection prior to start cryopreservation procedures, additives to freezing and thawing extenders, relevance of the AI-technique and insemination-to-ovulation interval. In conclusion, most of these progresses have allowed counteracting better boar sperm cryodamage and are thus considered as forward steps for this storage method. It is also worth noting that, despite being lower than fresh/extended semen, reproductive performance outcomes following AI with frozen-thawed boar sperm are currently acceptable.

Fertilisation rate obtained with frozen-thawed boar semen supplemented with rosmarinic acid using a single insemination timed according to vulvar skin temperature changes

Artificial insemination (AI) of sows with frozen-thawed semen usually results in lower pregnancy rates and litter sizes than the use of liquid preserved semen. The present study evaluated the effectiveness of vulvar skin temperature changes as a predictor of ovulation in sows and determined the fertility rates obtained after AI with frozen-thawed semen supplemented with rosmarinic acid (RA). Semen was collected from mature boars and cryopreserved in experimental extenders supplemented with or without 105 μM of RA. Multiparous sows were inseminated with a single dose of semen when vulvar skin temperature decreased to a value below 35 °C. Intrauterine insemination was performed using 1.5 × 109 spermatozoa. The sows were slaughtered 48 h after AI and the embryos and oocytes were recovered from the oviducts. Total and progressive motility, viability and acrosome integrity were significantly (P < 0.05) higher in RA-supplemented semen samples compared with the control. Fertilisation occurred in all sows inseminated in the study, although there were no significant differences between the experimental groups. Sows inseminated with RA-supplemented semen showed a slight increase in the number of embryos recovered as compared to sows inseminated with control semen. In conclusion, insemination according to vulvar skin temperature changes resulted in successful fertilisation in all sows, although supplementation of the freezing media with RA did not improve the fertilising ability of frozen-thawed boar sperm.

Antioxidant effect of lemon balm (Melissa officinalis) and mate tea (Ilex paraguensys) on quality, lipid peroxidation and DNA oxidation of cryopreserved boar epididymal spermatozoa

In this study, we investigated the protective ability of the addition of two antioxidant herb extracts, mate tea and lemon balm, on boar epididymal frozen-thawed spermatozoa quality. Testes from mature boars were collected at local slaughterhouse, and sperm samples from epididymis were recovered by flushing. Spermatozoa were cryopreserved in lactose-egg yolk buffer supplemented with various concentrations of lemon balm and mate tea (0, 2.5, 5 and 10 g l(-1) ) using the straw-freezing procedure. Motion parameters, acrosome and plasma membrane integrity, lipoperoxidation levels and DNA oxidative damage (8-hydroxy-2'-deoxyguanosine base lesion) were evaluated. There were no differences among experimental groups with regard to motility characteristics, viability, acrosome and plasma membrane integrity; however, the highest concentration of lemon balm produced significant (P < 0.05) improvement in curvilinear trajectory, straightness and amplitude of lateral head displacement after thawing. The supplementation of freezing extender with mate tea and lemon balm reduced sperm lipid membrane peroxidation, and only mate tea protected DNA against oxidative damage during cryopreservation at 120 min post-thawing (P < 0.05). Mate tea experimental extender at concentration of 10 g l(-1) showed the lowest percentage of sperm oxidised DNA and malondialdehyde generation; thus, mate tea is a potential candidate such as antioxidant compound on boar sperm cryopreservation medium.

Rosmarinic acid improves function and in vitro fertilising ability of boar sperm after cryopreservation

During cryopreservation, oxidative stress exerts physical and chemical changes on sperm functionality. In the present study we investigated the antioxidant effect of rosmarinic acid (RA) on quality and fertilising ability of frozen-thawed boar spermatozoa. Ejaculates collected from mature boar were cryopreserved in lactose-egg yolk buffer supplemented with different concentrations of RA (0 μM, 26.25 μM, 52.5 μM and 105 μM). Motion parameters, acrosome and plasma membrane integrity, lipoperoxidation levels, DNA oxidative damage (8-hydroxy-2-deoxyguanosine base lesion) and in vitro fertilisation ability were evaluated. Total and progressive motility were significantly higher in experimental extenders with RA than in the control (P<0.05) at 0 and 120 min post-thawing. The plasma and acrosomal membrane integrity were improved by supplementation with 105 μMRA (P<0.05). Negative correlation between RA and malondialdehyde (MDA) concentration were determined (P<0.05). After thawing, the percentage of spermatozoa with oxidised DNA did not differ between extenders, however, at 120 and 240 min post-thawing, the samples supplemented with 105 μMRA showed the lowest DNA oxidation rate (P<0.05). The penetration rate was significantly higher on spermatozoa cryopreserved with 105 μMRA (P<0.05). The results suggest that RA provides a protection for boar spermatozoa against oxidative stress during cryopreservation by their antioxidant properties.