Dietary omega-3 and -6 polyunsaturated fatty acids affect the composition and development of sheep granulosa cells, oocytes and embryos

Docosahexaenoic acid supplementation during porcine oocyte in vitro maturation improves oocyte quality and embryonic development by enhancing the homeostasis of energy metabolism

Although supplementation with docosahexaenoic acid (DHA) during porcine oocyte IVM is well-established, the available data are limited due to the lack of consistency. Moreover, to our knowledge, the anti-oxidant effects of DHA on porcine oocytes have not been reported. Hence, this study aimed to examine the effects of DHA supplementation on the regulation of energy metabolism during porcine oocyte maturation to improve oocyte maturation and embryonic development. By supplementing the IVM medium with various DHA concentrations, 25 μM DHA was identified as the optimal concentration which improved intraoocyte glutathione content and enhanced embryonic development after parthenogenesis. Compared to embryos derived from the control group, those derived from SCNT or IVF showed significantly improved blastocyst formation upon DHA supplementation during IVM. In addition, various transcription factors associated with oocyte development and apoptosis in mature oocytes were beneficially regulated in the DHA-treated oocytes. Moreover, DHA improved the AMP-activated protein kinase (AMPK)-regulatory ability of porcine oocytes and ameliorated nuclear maturation and embryonic development, which were decreased by artificially downregulating AMPK. To our knowledge, this is the first study to examine the effects of DHA as an AMPK regulator on oocyte maturation and embryo development in pigs. Furthermore, DHA addition to the IVM medium upregulated the relative expression of genes associated with mitochondrial potential and lipid metabolism. Therefore, the membrane potential of mitochondria (evaluated based on the JC-1 aggregate/JC-1 monomer ratio) and the levels of fatty acids and lipid droplets in matured oocytes increased, resulting in increased ATP synthesis. In conclusion, the DHA treatment of porcine oocytes with 25 μM DHA during IVM enhances the homeostasis of energy metabolism by improving mitochondrial function and lipid metabolism, leading to improved quality of matured oocytes and enhanced embryonic developmental potential of in vitro produced (IVP) embryos. Thus, 25 μM DHA supplementation could serve as a tool for improving the quality of IVP embryos. The study findings provide a basis for further research on improving the production efficiency of cloned animals by securing high-quality matured oocytes and enhancing energy metabolism in mammalian oocytes, including those of pigs.

Mitigating Effect of Lepidium sativum Seeds Oil on Ovarian Oxidative Stress, DNA Abnormality and Hormonal Disturbances Induced by Acrylamide in Rats

Acrylamide (ACR), an industrial compound, causes both male and female reproductive toxicity. Lepidium sativum seeds (L. sativum) (Garden cress) are known for their health benefits as antioxidant, antiasthmatic, anticoagulant, anti-inflammatory, and analgesic agents. Therefore, this study aimed to investigate the phytochemistry and nutritional value of L. sativum seeds oil for attenuating the ovarian damage induced by acrylamide in rats. The phytochemical investigation of the seeds revealed the presence of vitamins, potassium, iron, sugar and amino acids. Twenty eight compounds from the unsaponifiable fraction and twenty three compounds from the saponifiable fraction were identified. Three sterols and two triterpenes were isolated and identified as β-sitosterol (1), ▵5-avenasterol (2), friedelanol (3), stigmasta-4, 22-dien-3-one (4), and ursolic acid (5). Treatment of acrylamide-induced rats with L. sativum seeds oil ameliorated prolactin (PRL), progesterone (P4), estradiol (E2), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF- α) with variable degrees. The histopathological findings of ovaries supported these results. In conclusion, compounds (3-5) were isolated for the first time from L. sativum seeds oil. The seeds oil attenuated the ovarian damage and could potentially be a new supplemental agent against female infertility.

Lifestyle and fertility-specific quality of life affect reproductive outcomes in couples undergoing in vitro fertilization

Objective

A Mediterranean dietary pattern, sleeping habits, physical activity, and lifestyle appear to affect reproductive health. There are few reports about whether fertility-specific quality of life (QOL) is linked to infertility treatment outcomes. The aim of this study is to investigate when lifestyle factors and fertility-specific QOL are comprehensively considered, which factors influence assisted reproductive technology (ART) outcomes.

Methods

This prospective cohort includes 291 women undergoing a first ART treatment at multiple centers in Japan and was designed to evaluate the influence of diet, physical activity, sleeping pattern, computer use duration, and fertility-specific quality of life tool (FertiQoL) score on ART treatment outcomes using a questionnaire. The primary endpoint was the good-quality blastocyst rate per oocyte retrieval and the secondary endpoints were a positive pregnancy test and gestational sac (GS) detection.

Results

The good-quality blastocyst rate per oocyte retrieval tended to be negatively associated with frequent fish consumption. After all embryo transfer (ET) cycles, a positive pregnancy test tended to be positively associated with longer sleep and longer computer use (OR = 1.6, 95% CI = 0.9-2.7 and OR = 1.7, CI = 1.0-2.8, respectively) and negatively associated with a smoking partner (OR = 0.6, CI = 0.3-1.0). GS detection was positively and significantly associated with frequent olive oil intake and longer computer use (OR = 1.7, CI = 1.0-3.0 and OR = 1.7, CI = 1.0-3.0, respectively). After ET cycles with a single blastocyst, a positive pregnancy test was positively and significantly associated with longer computer use (OR = 2.0, CI = 1.1-3.7), while GS detection was significantly more likely in women with longer computer use (OR = 2.1, CI = 1.1-3.8) and tended to be more likely in women with a higher FertiQoL Total scaled treatment score (OR = 1.8, CI = 1.0-3.3). p < 0.05 was considered statistically significant and 0.05 ≤ p <0.01 as tendency.

Conclusions

Olive oil may be an important factor in dietary habits. Fertility-specific QOL and smoking cessation guidance for partners are important for infertile couples.

Low-input lipidomics reveals lipid metabolism remodelling during early mammalian embryo development

Lipids are indispensable for energy storage, membrane structure and cell signalling. However, dynamic changes in various categories of endogenous lipids in mammalian early embryonic development have not been systematically characterized. Here we comprehensively investigated the dynamic lipid landscape during mouse and human early embryo development. Lipid signatures of different developmental stages are distinct, particularly for the phospholipid classes. We highlight that the high degree of phospholipid unsaturation is a conserved feature as embryos develop to the blastocyst stage. Moreover, we show that lipid desaturases such as SCD1 are required for in vitro blastocyst development and blastocyst implantation. One of the mechanisms is through the regulation of unsaturated fatty-acid-mediated fluidity of the plasma membrane and apical proteins and the establishment of apical-basal polarity during development of the eight-cell embryo to the blastocyst. Overall, our study provides an invaluable resource about the remodelling of the endogenous lipidome in mammalian preimplantation embryo development and mechanistic insights into the regulation of embryogenesis and implantation by lipid unsaturation.

Navigating the Challenges of Gluten Enteropathy and Infertility: The Role of Celiac-Related Antibodies and Dietary Changes

Celiac disease (CD) is an autoimmune condition that is initiated in genetically susceptible individuals by the exposure of the intestines to gluten, and the early start of symptoms is related to malabsorption. Atypical variants of the illness are often identified in adulthood and are frequently associated with manifestations outside of the intestines, including metabolic osteopathy, anemia, and dermatitis herpetiformis. But also, empirical data suggest a correlation between CD and reproductive abnormalities, including repeated abortions. Infertility and repeated miscarriages frequently manifest in women diagnosed with CD and may serve as the initial clinical indication of a subclinical form. Furthermore, the condition may manifest as amenorrhea, infertility, and the delivery of infants with a low birth weight. Regarding the mechanisms of CD in infertility, along with the anti-tTG action to hinder the invasiveness of trophoblast, these antibodies could damage endometrial angiogenesis, which has been shown in in vitro models with human endometrial cells and in vivo in murine models. Another important aspect is the role of nutrient deficiencies, such as zinc deficiency (connected to impaired hormone production, secondary amenorrhea, and pre-eclampsia) and folic acid, etc. Therefore, our objective was to conduct a comprehensive review of the existing literature pertaining to this specific topic and to elucidate the role of the autoantibodies in its pathogenesis.

How the Oviduct Lipidomic Profile Changes over Time after the Start of an Obesogenic Diet in an Outbred Mouse Model

We investigated whether a high-fat/high-sugar (HF/HS) diet alters the lipidomic profile of the oviductal epithelium (OE) and studied the patterns of these changes over time. Female outbred Swiss mice were fed either a control (10% fat) or HF/HS (60% fat, 20% fructose) diet. Mice (n = 3 per treatment per time point) were sacrificed and oviducts were collected at 3 days and 1, 4, 8, 12 and 16 weeks on the diet. Lipids in the OE were imaged using matrix-assisted laser desorption ionisation mass spectrometry imaging. Discriminative m/z values and differentially regulated lipids were determined in the HF/HS versus control OEs at each time point. Feeding the obesogenic diet resulted in acute changes in the lipid profile in the OE already after 3 days, and thus even before the development of an obese phenotype. The changes in the lipid profile of the OE progressively increased and became more persistent after long-term HF/HS diet feeding. Functional annotation revealed a differential abundance of phospholipids, sphingomyelins and lysophospholipids in particular. These alterations appear to be not only caused by the direct accumulation of the excess circulating dietary fat but also a reduction in the de novo synthesis of several lipid classes, due to oxidative stress and endoplasmic reticulum dysfunction. The described diet-induced lipidomic changes suggest alterations in the OE functions and the oviductal microenvironment which may impact crucial reproductive events that take place in the oviduct, such as fertilization and early embryo development.

Dietary n-3 PUFA augments pre-ovulatory follicle turnover and prolificacy in well-fed ewes

The present study evaluated the effect of dietary supplementation with n-3 polyunsaturated fatty acids (PUFA) on preovulatory follicle (POF) turnover, prolificacy, and endocrine and metabolic milieu in Malpura sheep. Fifty cyclic ewes with 3-3.5 body condition scores on a five-point scale were allocated equally to two groups (n = 25) following estrus synchronization and were supplemented with 0.6 mL/kg body weight of n-3 PUFA-rich fish oil (FO) or palm oil (PO) as control, for 60 d following an acclimatization period of 7 d. All ewes were mated with sexually active rams at the end of the supplementation period. On ultrasonographic ovarian scanning at the last fourth estrus, the mean number of POFs was 77.8% greater (P < 0.01) in FO ewes than in the PO ewes. The proportion of ewes with multiple ovulations two months after the beginning of supplementation was 56% in the FO group as compared to 8% in the PO group. The number of fetuses was 46% higher (P < 0.01) in the FO than in the PO ewes at d 45 of gestation. At lambing, the twinning percent in the FO ewes was three times greater than in the PO ewes (27.3 vs. 9.1%). Plasma cholesterol, estradiol, and insulin concentrations were lower (P < 0.01) in ewes fed with FO than those offered PO group at the end of the feeding period. It was concluded that the dietary supplementation of n-3 PUFA-rich FO in well-fed Malpura ewes improved the number of follicles and ovulation rate which led to an increased prolificacy, accompanied by a reduction of plasma cholesterols, estradiol, and insulin.

Fish oil supplementation protects against protein undernutrition-induced testicular and ovarian biochemical alterations in rats

Proteins are required for biological functions and their inadequacy might impair the growth and development of the reproductive system. The study investigated the effects of fish oil (FO) supplementation on low-protein diet-induced alterations in male and female reproductive organs. Male and female rats were assigned randomly to four groups respectively. The NPD rats had five rats per group and were given 16% casein diet while the LPD rats had eight rats per group and received 5% casein diet. After the 8th week, FO was administered for 3 weeks via oral gavage at a concentration of 400mg Kg^-1 after which the rats were sacrificed and testes and ovaries were excised. LPD-fed rats showed lower body weights for both genders. In LPD-fed rats, NO was significantly increased while GSH, vitamins C and E levels, the activities of CAT (except in ovaries), and GST were significantly reduced in both tissues. The activities of SOD and GPx were only reduced in the testes including sperm count, motility, and increase deformed sperm cells. Testosterone and progesterone levels were also reduced and lipid homeostasis was disrupted in the plasma of LPD-fed rats. FO supplementation reduces the NO, CHOL, TG, LDL (in females), and VLDL but significantly improves HDL (in females), testosterone, and progesterone levels, sperm count, motility, and morphology. The antioxidant status of both tissues also increased significantly in LPD-fed rats. Conclusively, FO might be effective in improving testicular and ovarian functions and for the maintenance of plasma lipid homeostasis in LPD-fed rats.

Nutrition, female fertility and in vitro fertilization outcomes

The investigation of modifiable factors that may exert influences on female reproductive health and in vitro fertilization (IVF) outcomes is increasing. Growing attention is being paid to nutrition. The aim of the present review is to recapitulate the current understanding on the effects of nutrition on female fertility and IVF outcomes. In particular, the three main classes of macromolecules have been analysed i.e. carbohydrates, proteins and fatty acids. An increasing number of studies have focused on the potential benefit of whole grain, vegetables and omega-3 polynsatured fatty acids (ω-3 PUFAs) on reproductive outcomes. Controversial results exist regarding the consumption of omega-6 (ω-6) PUFAs and dairy. Overall, nutrition appears to represent a modifiable factor that may play a significant role in the context of female reproduction and IVF outcomes, but the limited number of studies and the discrepancies between the available data call for further research in the area.

High-Fat Diet and Female Fertility across Lifespan: A Comparative Lesson from Mammal Models

Female reproduction focuses mainly on achieving fully grown follicles and competent oocytes to be successfully fertilized, as well as on nourishing the developing offspring once pregnancy occurs. Current evidence demonstrates that obesity and/or high-fat diet regimes can perturbate these processes, leading to female infertility and transgenerational disorders. Since the mechanisms and reproductive processes involved are not yet fully clarified, the present review is designed as a systematic and comparative survey of the available literature. The available data demonstrate the adverse influences of obesity on diverse reproductive processes, such as folliculogenesis, oogenesis, and embryo development/implant. The negative reproductive impact may be attributed to a direct action on reproductive somatic and germinal compartments and/or to an indirect influence mediated by the endocrine, metabolic, and immune axis control systems. Overall, the present review highlights the fragmentation of the current information limiting the comprehension of the reproductive impact of a high-fat diet. Based on the incidence and prevalence of obesity in the Western countries, this topic becomes a research challenge to increase self-awareness of dietary reproductive risk to propose solid and rigorous preventive dietary regimes, as well as to develop targeted pharmacological interventions.

Effects of omega-3 polyunsaturated fatty acids on cellular development in human ovarian granulosa tumor cells (KGN)

Emerging research has shown that polyunsaturated fatty acids (PUFAs) benefit human health and exert anti-cancer effects. However, there is little understanding of the specific mechanisms by which PUFAs regulate the cells of the ovarian granulosa tumor. In the current study, we investigate the effects and the possible mechanisms of PUFAs on human ovarian tumor cells development. KGN cells were treated with omega-3. Small interfering (siRNA) and specific activator were used to knock down and overexpress gene expression in KGN cells. The protein content levels were analyzed by Western blot. Cell viability, proliferation and apoptosis assay were performed to examine the cellular development. And the level of glucose uptake in KGN cells were assessed by 2-DG measurement. The results showed that omega-3 treatment reduced cell viability, proliferation and increased cell apoptosis. Further studies showed that omega-3 also reduced GLUT1/4 protein content and cellular glucose uptake. Subsequent knockdown and overexpression of OCT4 using Oct4 siRNA and O4I2 (OCT4 activator) showed that OCT4 was involved in the regulations of omega-3 on GLUT1/4 expression and cell development. Our data demonstrate that omega-3 inhibits cellular development by down-regulating GLUT1/4 expression and glucose uptake in KGN cells, which are mediated through OCT4.

Metabolic and antioxidant status during transition is associated with changes in the granulosa cell transcriptome in the preovulatory follicle in high-producing dairy cows at the time of breeding

In this study, we hypothesized that early postpartum (pp) metabolic and oxidative stress conditions in dairy cows (particularly those with severe negative energy balance, NEB) are associated with long-term changes in granulosa cell (GC) functions in the preovulatory follicle at the time of breeding. Blood samples were collected at wk 2 and wk 8 pp from 47 healthy multiparous cows. Follicular fluid (FF) and GC were collected from the preovulatory follicle after estrous synchronization at wk 8. Several metabolic and antioxidant parameters were measured in blood and FF, and their correlations were studied. Subsequently, 27 representative GC samples were selected for RNA sequencing analysis. The GC gene expression data of LH-responsive genes and the estradiol:progesterone ratio in FF were used to identify pre- and post-LH surge cohorts. We compared the transcriptomic profile of subgroups of cows within the highest and lowest quartiles (Q4 vs. Q1) of each parameter, focusing on the pre-LH surge cohort (n = 16, at least 3 in each subgroup). Differentially expressed genes (DEG: adjusted P-value < 0.05, 5% false discovery rate) were determined using DESeq2 analysis and were functionally annotated. Blood and FF β-carotene and vitamin E concentrations at wk 2, but not at wk 8, were associated with the most pronounced transcriptomic differences in the GC, with up to 341 DEG indicative for lower catabolism, increased oxidoreductase activity and signaling cascades that are known to enhance oocyte developmental competence, increased responsiveness to LH, and a higher steroidogenic activity. In contrast, elevated blood NEFA concentrations at wk 2 (and not at wk 8) were associated with a long-term carryover effect detectable in the GC transcriptome at wk 8 (64 DEG). These genes are related to response to lipids and ketones, oxidative stress, and immune responses, which suggests persistent cellular stress and oxidative damage. This effect was more pronounced in cows with antioxidant deficiencies at wk 8 (up to 148 DEG), with more genes involved in oxidative stress-dependent responses, apoptosis, autophagy and catabolic processes, and mitochondrial damage. Interestingly, within the severe NEB cows (high blood NEFA at wk 2), blood antioxidant concentrations (high vs. low) at wk 8 were associated with up to 194 DEG involved in activation of meiosis and other signaling pathways, indicating a better oocyte supportive capacity. This suggests that the cow antioxidant profile at the time of breeding might alleviate, at least in part, the effect of NEB on GC functions. In conclusion, these results provide further evidence that the metabolic and oxidative stress in dairy cows early postpartum can have long-term effects on GC functions in preovulatory follicles at the time of breeding. The interplay between the effects of antioxidants and NEFA illustrated here might be useful to develop intervention strategies to minimize the effect of severe NEB on fertility.

Female infertility and diet, is there a role for a personalized nutritional approach in assisted reproductive technologies? A Narrative Review

Female infertility is a major public health concern and a global challenge. It is a disorder of the reproductive system, defined as the inability to achieve a clinical pregnancy. Nutrition and other environmental factors are found to impact reproductive health in women as well as the outcome of assisted reproductive technologies (ART). Dietary factors, such as polyunsaturated fatty acids (PUFA), fiber as well as the intake of Mediterranean diet appear to exert beneficial effects on female reproductive outcomes. The exact mechanisms associating diet to female fertility are yet to be identified, although genomic, epigenomic, and microbial pathways may be implicated. This review aims to summarize the current knowledge on the impact of dietary components on female reproduction and ART outcomes, and to discuss the relevant interplay of diet with genome, epigenome and microbial composition.

Preovulatory serum estradiol concentration is positively associated with oocyte ATP and follicular fluid metabolite abundance in lactating beef cattle

Cattle induced to ovulate a small, physiologically immature preovulatory follicle had reduced oocyte developmental competence that resulted in decreased embryo cleavage and day 7 embryo quality compared with animals induced to ovulate a more advanced follicle. RNA-sequencing was performed on oocytes and their corresponding cumulus cells approximately 23 h after gonadotropin-releasing hormone (GnRH) administration to induce the preovulatory gonadotropin surge suggested reduced capacity for glucose metabolism and oxidative phosphorylation in the cumulus cells and oocytes from follicles ≤11.7 mm, respectively. We hypothesized that induced ovulation of a small, physiologically immature preovulatory follicle results in a suboptimal follicular microenvironment and reduced oocyte metabolic capacity. We performed a study with the objective to determine the impact of preovulatory follicle diameter and serum estradiol concentration at GnRH administration on oocyte metabolic competence and follicular fluid metabolome profiles. We synchronized the development of a preovulatory follicle and collected the follicle contents via transvaginal aspiration approximately 19 h after GnRH administration in lactating beef cows (n = 319). We determined ATP levels and mitochondrial DNA (mtDNA) copy number in 110 oocytes and performed ultra-high-performance liquid chromatography–high resolution mass spectrometry metabolomic studies on 45 follicular fluid samples. Intraoocyte ATP and the amount of ATP produced per mtDNA copy number were associated with serum estradiol concentration at GnRH and time from GnRH administration to follicle aspiration (P < 0.05). mtDNA copy number was not related to follicle diameter at GnRH, serum estradiol concentration at GnRH, or any potential covariates (P > 0.10). We detected 90 metabolites in the aspirated follicular fluid. We identified 22 metabolites associated with serum estradiol concentration at GnRH and 63 metabolites associated with follicular fluid progesterone concentration at the time of follicle aspiration (FDR < 0.10). Pathway enrichment analysis of significant metabolites suggested altered proteinogenesis, citric acid cycle, and pyrimidine metabolism in follicles of reduced estrogenic capacity pre-gonadotropin surge or reduced progesterone production by the time of follicle aspiration.

Carnitines as Mitochondrial Modulators of Oocyte and Embryo Bioenergetics

Recently, the importance of bioenergetics in the reproductive process has emerged. For its energetic demand, the oocyte relies on numerous mitochondria, whose activity increases during embryo development under a fine regulation to limit ROS production. Healthy oocyte mitochondria require a balance of pyruvate and fatty acid oxidation. Transport of activated fatty acids into mitochondria requires carnitine. In this regard, the interest in the role of carnitines as mitochondrial modulators in oocyte and embryos is increasing. Carnitine pool includes the un-esterified l-carnitine (LC) and carnitine esters, such as acetyl-l-carnitine (ALC) and propionyl-l-carnitine (PLC). In this review, carnitine medium supplementation for counteracting energetic and redox unbalance during in vitro culture and cryopreservation is reported. Although most studies have focused on LC, there is new evidence that the addition of ALC and/or PLC may boost LC effects. Pathways activated by carnitines include antiapoptotic, antiglycative, antioxidant, and antiinflammatory signaling. Nevertheless, the potential of carnitine to improve energetic metabolism and oocyte and embryo competence remains poorly investigated. The importance of carnitine as a mitochondrial modulator may suggest that this molecule may exert a beneficial role in ovarian disfunctions associated with metabolic and mitochondrial alterations, including PCOS and reproductive aging.

Effects of NEFAs during IVM on pig embryos from granulosa cell-cocultured oocytes

Circulating levels of nonesterified fatty acids (NEFAs) are elevated in some females, which can impair oocyte maturation and embryo development, and may alter the phenotype of the progeny. However, the effects of NEFAs on human embryo development are not clear due to ethical limitations. Thus, we used pig as the model to investigate the impacts of NEFAs on oocyte and embryo due to their similar reproductive and metabolic physiologies to humans. In this study, porcine cumulus-oocyte complexes were in vitro maturated under a pathologically high concentration of NEFAs (468 μM palmitic acid, 194 μM stearic acid, and 534 μM oleic acid) with the presence of granulosa cell monolayer, in contrast to control without NEFAs. The mature oocytes were fertilized to produce embryos for further analysis of the transcriptome and DNA methylation patterns. The elevated level of NEFAs decreased the blastocyst rate and delayed the blastocyst development. Ingenuity pathway analysis showed that the most affected gene pathways were related mainly to cell activities, metabolism, and inflammation. These findings indicated that oocytes exposed to the exogenous high level of NEFAs during in vitro maturation resulted in altered gene expression and DNA methylation of early embryos, which have detrimental impacts on blastocyst quality.

In vitro embryo production from early antral follicles of goats fed with a whole full-fat linseed based diet

The present study aimed to use an in vitro follicle culture (IVFC) biotechnique as a tool to evaluate the influence of whole flaxseed as a feed supplementation in the diet on the in vitro development of caprine early antral follicles (EAFs) and further embryo production. In total, 18 adult goats were homogeneously allocated into two diet groups: Control and Flaxseed. EAFs from both experimental groups (300-400 µm) were isolated and cultured in vitro for 18 days. After IVFC, recovered cumulus-oocyte complexes were submitted to in vitro maturation, and subsequently to IVF and in vitro embryo culture. The endpoints evaluated were follicular growth and morphology, oocyte recovery rate and diameter, sperm penetration, pronuclei formation, embryo development, and estradiol production. The addition of the whole flaxseed in the diet did not affect (P > 0.05) follicular growth and diameter. A higher (P < 0.05) percentage of oocytes ≥ 110 µm was recovered from the flaxseed treatment. However, the sperm penetration rate was higher (P < 0.05) in the control treatment when compared with the flaxseed treatment, but no differences were found regarding the rate of fertilization nor cleaved embryos. In conclusion, dietary flaxseed increased the recovery rate of fully grown oocytes, but it did negatively affect the sperm penetration rate, even though there was no further effect on the cleavage rate.

Alterations of Serum Metabolites and Fecal Microbiota Involved in Ewe Follicular Cyst

While the interactions of the gut microbiome and blood metabolome have been widely studied in polycystic ovary disease in women, follicular cysts of ewes have been scarcely investigated using these methods. In this study, the fecal microbiome and serum metabolome were used to compare between ewes diagnosed with ovarian cystic follicles and ewes with normal follicles, to investigate alterations of the fecal bacterial community composition and metabolic parameters in relation to follicular cystogenesis. Ewes from the same feeding and management system were diagnosed with a follicular cyst (n = 6) or confirmed to have normal follicles (n = 6) by using a B-mode ultrasound scanner. Blood serum and fresh fecal samples of all ewes were collected and analyzed. The α-diversity of fecal microbiome did not differ significantly between follicular cyst ewes and normal follicle ewes. Three genera (Bacteroides, Anaerosporobacter, and Angelakisella) were identified and their balance differentiated between follicular cyst and normal follicle ewes. Alterations of several serum metabolite concentrations, belonging to lipids and lipid-like molecules, organic acids and derivatives, organic oxygen compounds, benzenoids, phenylpropanoids and polyketides, and organoheterocyclic compounds, were associated with the presence of a follicular cyst. Correlation analysis between fecal bacterial communities and serum metabolites indicated a positive correlation between Anaerosporobacter and several fatty acids, and a negative correlation between Bacteroides and L-proline. These observations provide new insights for the complex interactions of the gut microbiota and the host serum lipid profiles, and support gut microbiota as a potential strategy to treat and prevent follicular cysts in sheep.

Possible Dietary Effects of Insect-Based Diets across Zebrafish (Danio rerio) Generations: A Multidisciplinary Study on the Larval Phase

Insects represent a valuable and sustainable alternative ingredient for aquafeed formulation. However, insect-based diets have often highlighted controversial results in different fish species, especially when high inclusion levels were used. Several studies have demonstrated that nutritional programming through parental feeding may allow the production of fish better adapted to use sub-optimal aquafeed ingredients. To date, this approach has never been explored on insect-based diets. In the present study, five experimental diets characterized by increasing fish meal substitution levels with full-fat Black Soldier Fly (Hermetia illucens; BSF) prepupae meal (0%, 25%, 50%, 75% and 100%) were used to investigate the effects of programming via broodstock nutrition on F1 zebrafish larvae development. The responses of offspring were assayed through biometric, gas chromatographic, histological, and molecular analyses. The results evidenced that the same BSF-based diets provided to adults were able to affect F1 zebrafish larvae fatty acid composition without impairing growth performances, hepatic lipid accumulation and gut health. Groups challenged with higher BSF inclusion with respect to fish meal (50%, 75% and 100%) showed a significant downregulation of stress response markers and a positive modulation of inflammatory cytokines gene expression. The present study evidences that nutritional programming through parental feeding may make it possible to extend the fish meal substitution level with BSF prepupae meal in the diet up to almost 100% without incurring the well-known negative side effects of BSF-based diets.

Interspecific Variation in One-Carbon Metabolism within the Ovarian Follicle, Oocyte, and Preimplantation Embryo: Consequences for Epigenetic Programming of DNA Methylation

One-carbon (1C) metabolism provides methyl groups for the synthesis and/or methylation of purines and pyrimidines, biogenic amines, proteins, and phospholipids. Our understanding of how 1C pathways operate, however, pertains mostly to the (rat) liver. Here we report that transcripts for all bar two genes (i.e., BHMT, MAT1A) encoding enzymes in the linked methionine-folate cycles are expressed in all cell types within the ovarian follicle, oocyte, and blastocyst in the cow, sheep, and pig; as well as in rat granulosa cells (GCs) and human KGN cells (a granulosa-like tumor cell line). Betaine-homocysteine methyltransferase (BHMT) protein was absent in bovine theca and GCs, as was activity of this enzyme in GCs. Mathematical modeling predicted that absence of this enzyme would lead to more volatile S-adenosylmethionine-mediated transmethylation in response to 1C substrate (e.g., methionine) or cofactor provision. We tested the sensitivity of bovine GCs to reduced methionine (from 50 to 10 µM) and observed a diminished flux of 1C units through the methionine cycle. We then used reduced-representation bisulfite sequencing to demonstrate that this reduction in methionine during bovine embryo culture leads to genome-wide alterations to DNA methylation in >1600 genes, including a cohort of imprinted genes linked to an abnormal fetal-overgrowth phenotype. Bovine ovarian and embryonic cells are acutely sensitive to methionine, but further experimentation is required to determine the significance of interspecific variation in BHMT expression.

Effects of a dietary supplement enriched in palmitoleic acid on fatty acid composition of follicular fluid, granulosa cell metabolism, and oocyte developmental capacity in early lactation dairy cows

In high-yielding dairy cows, some fertility traits can be influenced by the fatty acid (FA) composition of the follicular fluid during early lactation. The first objective of the current study was to evaluate the potential of dietary supplements enriched in specific FA to influence the FA composition of follicular fluid lipid classes in early lactation dairy cows. The second objective was to determine the influence of the resulting follicular fluid FA composition on the folliculogenesis, lipid and energy metabolism of granulosa cells, as well as oocyte quality and embryo development. Twenty Holstein multiparous cows in late gestation were randomly assigned to 200 g/d of FA supplements enriched in (1) palmitic acid (control treatment; 82% 16:0; PA) in the rumen or (2) palmitoleic acid (sea buckthorn oil; 27% cis-9 16:1, 28% 16:0, 22% cis-9 18:1, and 11% cis-9,cis-12 18:2; SBT) in the abomasum. The treatment period ranged from 20 ± 5 d precalving to 67 ± 2 d postcalving. Cumulus-oocyte complexes, granulosa cells, and follicular fluid were recovered from 2 sequential sessions of ovum pick-up (OPU-1 and OPU-2) at 46 and 67 ± 2 d postcalving (mean ± standard deviation). On the same days, blood samples were collected. Milk performance was recorded, and feed and milk samples were collected from d 8 to 10 ± 3 (onset of lactation), d 35 to 37 ± 2 (before OPU-1), and d 63 to 65 ± 2 (before OPU-2). Treatments did not affect milk yield or fat concentration throughout the experimental trial. Compared with PA, SBT increased the cis-9 16:1 concentration in milk fat, in plasma esterified lipid classes (phospholipids, cholesterol esters, and triacylglycerols), and in follicular fluid phospholipids and cholesterol esters at OPU-1. Abundance of mRNA for stearoyl-CoA desaturase 1 and 5, and perilipin 2 in granulosa cells was not different between treatments, but an increase in the level of stearoyl-CoA desaturase 5 was observed between the 2 OPU periods. Treatments did not affect oocyte quality and developmental capacity or embryo lipid metabolism when cultivated in vitro. These results suggest that limited modifications in the FA composition of the oocyte microenvironment via dietary lipid supplements enriched in specific FA had no major effects on granulosa cell metabolism and oocyte developmental capacity in early lactation cows.

Stimulation of follicle growth and development during estrus in Ettawa Grade does fed a flushing supplement of different polyunsaturated fatty acids

Background and Aim

Flushing with the manipulation of fatty acids, particularly polyunsaturated fatty acids, like linoleic and α-linolenic acids in the ration, is a strategy to raise the nutritional status of the female mammals to improve ovarian function and follicle development. This study was designed to investigate the effectiveness of flushing supplementation with different types of polyunsaturated and saturated fatty acids in stimulating follicle growth and development during estrus in Ettawa Grade does with a low initial body condition score (BCS ≤2).

Materials and Methods

Eighteen Ettawa Grade does in the second parity, with an average body weight of 32.11±2.19 kg, were divided into three groups according to the fatty acid supplemented to their ration: (i) About 2.8% lauric acid flushing (group); (ii) 2.8% linoleic acid flushing (LA group); and (iii) 2.8% α-linolenic acid flushing (ALA group). The ration was formulated to be isocaloric (total digestible nutrient = 77%) and isonitrogenous (crude protein = 15%). The experiment was conducted for 35 days; that is, 14 days for acclimatization and synchronization of the estrous cycle and 21 days for fatty acid flushing until the appearance of the next estrus. A completely randomized design was applied.

Results

According to the results, none of the different fatty acids in the ration affected the nutrient intakes, BCSs, average daily gains, and plasma glucose, cholesterol, and progesterone concentrations of the three groups of does. However, the BCSs (by 0.8-0.9) and the plasma cholesterol concentrations were higher after fatty acid flushing for 21 days than before the flushing period. The ALA group had the highest number of large-sized preovulatory follicles, whereas the LAURIC group had the highest plasma estradiol concentration during estrus. All three groups had similar plasma progesterone concentrations during estrus after fatty acid flushing.

Conclusion

Flushing supplementation with 2.8% ALA from flaxseed oil gave the best results in terms of stimulating the highest number of large-sized preovulatory follicles in Ettawa Grade does.

Effects of the FABP4 gene on steroid hormone secretion in goose ovarian granulosa cells

1. To investigate the physiological role of FABP4 in the goose ovary, this study determined the effects of overexpressing and siRNA interfering FABP4 on progesterone (P₄) and oestradiol (E₂) production in granulosa cells. Measurements were made by ELISA, real-time qRT-PCR and western blotting. 2. The concentrations of P₄ and E₂ in the FABP4 overexpression granulosa cells were increased compared to the control group (P > 0.05 for P₄; P < 0.05 for E₂). Likewise, the mRNA and protein expression levels of CYP11A1 and CYP19A1 were significantly higher than in the control group (P < 0.05 or P < 0.001). Conversely, the concentrations of P₄ and E₂ in the FABP4 silencing granulosa cells were significantly decreased compared with the control group (P < 0.001). Likewise, the mRNA and protein expression levels of CYP11A1 and CYP19A1 were significantly lower than in the control group (P < 0.001, or P < 0.01). 3. The study indicated that the FABP4 gene may regulate steroid hormone secretion and the expression of the steroidogenic genes in geese ovarian granulosa cells. These results support the possibility that the FABP4 gene mediates ovarian steroid hormone biosynthesis function and reproduction in geese.

Advances in fatty acids nutrition in dairy cows: from gut to cells and effects on performance

High producing dairy cows generally receive in the diet up to 5-6% of fat. This is a relatively low amount of fat in the diet compared to diets in monogastrics; however, dietary fat is important for dairy cows as demonstrated by the benefits of supplementing cows with various fatty acids (FA). Several FA are highly bioactive, especially by affecting the transcriptome; thus, they have nutrigenomic effects. In the present review, we provide an up-to-date understanding of the utilization of FA by dairy cows including the main processes affecting FA in the rumen, molecular aspects of the absorption of FA by the gut, synthesis, secretion, and utilization of chylomicrons; uptake and metabolism of FA by peripheral tissues, with a main emphasis on the liver, and main transcription factors regulated by FA. Most of the advances in FA utilization by rumen microorganisms and intestinal absorption of FA in dairy cows were made before the end of the last century with little information generated afterwards. However, large advances on the molecular aspects of intestinal absorption and cellular uptake of FA were made on monogastric species in the last 20 years. We provide a model of FA utilization in dairy cows by using information generated in monogastrics and enriching it with data produced in dairy cows. We also reviewed the latest studies on the effects of dietary FA on milk yield, milk fatty acid composition, reproduction, and health in dairy cows. The reviewed data revealed a complex picture with the FA being active in each step of the way, starting from influencing rumen microbiota, regulating intestinal absorption, and affecting cellular uptake and utilization by peripheral tissues, making prediction on in vivo nutrigenomic effects of FA challenging.

Reproductive Performance of Dairy Cows Fed a Diet Supplemented with n-3 Polyunsaturated Fatty Acids – A Review

The aim of this review is to summarize the current state of knowledge of reproductive performance of high-yielding dairy cows fed a diet supplemented with n-3 fatty acids (FA s), and to recommend a feeding schedule that can increase the success rate in reproduction. Dietary supplementation with fat, especially FA, has become an accepted strategy for supporting the fertility of high-yielding dairy cows. The two main categories of FA s, unsaturated fatty acids (UFA s) and saturated fatty acids (SFA s), exert distinct effects on reproductive functions, with UFA having a conclusively beneficial impact. Polyunsaturated fatty acids (PUFAs) are of particular importance on account of their biological properties. Standard feedstuffs (such as soybean) are rich in n-6 FA s, whereas few feedstuffs contain n-3 FA s. Neither the n-3 nor n-6 PUFA s are synthetized by the animal. Several field experiments have indicated that the recommended schedule of n-3 supplementation should last 160–170 days, from the eighth week before calving to 100 or 120 days postpartum. Supplementation of the diet thus covers the period from the late preantral stage of the follicle, the entire development of the antrum, oocyte ovulation, and fertilization, as well as the development of the preattachment embryo and its implantation. The following effects are among the important beneficial results of supplementation with n-3 FA s: a higher number of antral follicles suitable for ovum pick-up (OPU), larger dominant follicles and corresponding CL, better quality oocytes and embryos, and higher implantation rates resulting from improved uterine environment (e.g., reduced synthesis of luteolytic PGF2α). We conclude that dietary supplementation for high-yielding dairy cows with n-3 FA s supports ovarian functions and helps the embryo to survive in the adverse environment of the reproductive tract of the postpartum cow.

Effects of dietary supplementation with algae, sunflower oil or soybean oil on folliculogenesis in the rabbit ovary during sexual maturation

This study aimed to examine the effects of algae (rich in omega-3 fatty acids), sunflower oil (rich in omega-6 fatty acids) and soybean oil (rich in omega-6 fatty acids) on the entire folliculogenesis in juvenile and sexually mature rabbits. After weaning, rabbits were randomly divided into four experimental groups of 14 animals each. Control animals received non-supplemented pellets, while in the other groups, the pellets contained 1% marine algae, 3% sunflower oil or 3% soybean oil. Animals from each group were slaughtered at 12 weeks of age (n = 7 per group) or at 18 weeks of age (n = 7 per group). The ovaries were harvested and fixed for hematoxylin-eosin staining, immunohistochemical localization of PCNA and TUNEL assay. Algae-enriched diet markedly decreased the number of primordial and primary follicles, while addition of sunflower oil reduced the number of primary follicles in 12-week-old rabbits. The number of antral follicles was higher following algae supplementation, but lower after addition of soybean oil in that age group. Proliferating index was decreased following supplementation with algae and soybean oil in juvenile rabbits, whereas it was increased after addition of algae and decreased following vegetable oils in mature ones. Dietary PUFAs did not impact apoptosis in the rabbit ovary of both age groups. The obtained results suggest that PUFA-enriched diet regulate either early folliculogenesis or antral follicle development in rabbits that might influence reproductive performance as a consequence. It appears that observed effects are attributed to sexual maturity.

Mammalian ovarian lipid distributions by desorption electrospray ionization-mass spectrometry (DESI-MS) imaging

Merging optical images of tissue sections with the spatial distributions of molecules seen by imaging mass spectrometry is a powerful approach to better understand the metabolic roles of the mapped molecules. Here, we use histologically friendly desorption electrospray ionization-mass spectrometry (DESI-MS) to map the lipid distribution in tissue sections of ovaries from cows (N = 8), sows (N = 3), and mice (N = 12). Morphologically friendly DESI-MS imaging allows the same sections to be examined for morphological information. Independent of the species, ovarian follicles, corpora lutea, and stroma could be differentiated by principal component analysis, showing that lipid profiles are well conserved among species. As examples of specific findings, arachidonic acid and the phosphatidylinositol PI(38:4), were both found concentrated in the follicles and corpora lutea, structures that promoted ovulation and implantation, respectively. Adrenic acid was spatially located in the corpora lutea, suggesting the importance of this fatty acid in the ovary luteal phase. In summary, lipid information captured by DESI-MS imaging could be related to ovarian structures and data were all conserved among cows, sows, and mice. Further application of DESI-MS imaging to either physiological or pathophysiological models of reproductive conditions will likely expand knowledge of the roles of specific lipids and pathways in ovarian activity and mammalian fertility. Graphical abstract Desorption electrospray ionization-mass spectrometry (DESI-MS) is performed directly from frozen ovarian tissue sections placed onto glass slides. Because the desorption and ionization process of small molecules is so gentle, the tissue architecture is preserved. The sample can then be stained and tissue morphology information can be overlaid with the chemical information obtained by DESI-MS.

Protective effect of alpha-lipoic acid and omega-3 fatty acids against cyclophosphamide-induced ovarian toxicity in rats

Background and Aim:

Cyclophosphamide therapy is known to be associated with the risk of female infertility as a result of ovarian toxicity. Alpha-lipoic acid (LA) and omega-3 fatty acids are known for their antioxidant and anti-inflammatory activities. The present study investigated the potential protective effect of alpha-LA, omega-3 fatty acids, and its combination against cyclophosphamide-induced ovarian toxicity in rats.

Materials and Methods:

Thirty rats were equally divided into Groups I, II, III, IV, and V. Group I was normal control, wherein the rats were fed with normal feed and water ad libitum. Group II served as cyclophosphamide-induced group, wherein the rats were injected with cyclophosphamide at 75 mg/kg through intraperitoneal route once a week to induce ovarian toxicity. Groups III and IV were treated with alpha-LA at the rate of 25 mg/kg and omega-3 fatty acids at the rate of 400 mg/kg, respectively, in parallel to cyclophosphamide induction as in Group II. Group V animals were coadministered with alpha-LA (25 mg/kg) and omega-3 fatty acids (400 mg/kg) along with cyclophosphamide induction as in Group II. The respective treatments were administered daily through oral route for a period of 30 days. Regularity of estrous cycle was evaluated by vaginal cytology. Post-treatment period, the animals were humanely sacrificed, and the blood samples were subjected to the estimation of follicle-stimulating hormone (FSH) and estrogen. The ovarian tissue was weighed and subjected to histopathology, transmission electron microscopy, estimation of decreased glutathione (GSH), and tumor necrosis factor (TNF)-alpha.

Results:

Rats treated with cyclophosphamide alone manifested irregularity in estrous cycle, increased FSH, and reduced estrogen levels. The ovaries showed decreased GSH and increased TNF-alpha concentrations. Histopathological and transmission electron microscopic analysis of the ovarian follicles revealed degenerative changes. Administration of alpha-LA and omega-3 fatty acids as well as the combination of both the treatments demonstrated significant normalization of the estrous cycle and antioxidant defense mechanism as well as ameliorated the hormonal profile and histological architecture of the ovarian follicles. However, appreciable synergistic efficacy of the combination therapy (alpha-LA+omega-3 fatty acids) with respect to the monotherapies was not observed in the present study.

Conclusion:

The efficacy of alpha-LA and omega-3 fatty acids against cyclophosphamide-induced ovarian toxicity could be attributed to its antioxidant and anti-inflammatory activities that prevented the oxidative damage to the ovaries caused by cyclophosphamide. Hence, our findings suggest that dietary supplementation of alpha-LA and omega-3 fatty acids in women receiving cyclophosphamide therapy could carry potential benefits in preventing cyclophosphamide-induced infertility in childbearing women.

Effect of dietary n-3 polyunsaturated rich fish oil supplementation on ovarian function and interferon stimulated genes in the repeat breeding cow

Dietary n-3 polyunsaturated fatty acids (n-3 PUFA) improve utero-ovarian functions and embryonic survival in postpartum dairy cows. Because early embryonic mortality is the major cause of repeat breeding (RB) in cows, there was investigation of the effect of dietary supplementation of n-3 PUFA [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] rich fish oil (FO) from -2 to +2 weeks of artificial insemination on the size of preovulatory follicle (POF), serum progesterone (P₄) and relative abundance of the mRNA of interferon stimulated genes (ISG) that encode for these proteins in the peripheral blood leukocytes (PBL) in the RB cow (n = 12). The diet of control group was supplemented with palm oil (PO). The results indicated serum concentrations of EPA and DHA were greater by 4.6- and 3.5-fold, respectively at the end of feeding study in the RB cows of the FO group. The diameter of POF was larger by 2.2 mm in FO group; however, serum P₄ did not vary from day 14-20 post-artificial insemination. Greater abundance of ISG mRNA transcripts such as ISG15, RTP4, Mx2 and OAS1 in the PBL of pregnant cows of FO group indicates day 20 conceptuses produced more IFN-τ. It is concluded that supplementation of FO during the breeding period increased the size of POF and enhanced the abundance of ISG mRNA transcripts in RB cows that became pregnant.

Roles of different n-3/n-6 PUFA ratios in ovarian cell development and steroidogenesis in PCOS rats

Polycystic ovary syndrome (PCOS) is a complex and common endocrine disorder characterized by hyperandrogenism, which is accompanied by follicle growth arrest at the small antral stage, minimal granulosa cell proliferation, and chronic anovulation. Polyunsaturated fatty acids (PUFAs) are necessary for the body's metabolism, growth and development. Although PUFAs play an important role in the regulation of female reproduction, their role in ovarian development in PCOS is still unclear. The present study was conducted to investigate the effects of different ratios of n-3/n-6 PUFAs (omega-3/omega-6) on ovary development in PCOS rats. Serum levels of reproductive hormones and enzymes related to steroidogenesis were assessed. The results indicated that PUFAs (n-3/n-6: 1/15) significantly increased ovarian weight and improved the ovarian structure although they had no significant effect on body weight in PCOS rats. Meanwhile, apoptosis was attenuated accompanied by increased cell proliferation by PUFAs (n-3/n-6: 1/15). Moreover, serum levels of hormones (FSH and E₂) were also significantly increased by PUFAs (n-3/n-6: 1/15) accompanied by decreased T levels. To investigate whether PUFAs regulate the expression of enzymes related to hormone synthesis, western blotting was used to determine the protein levels of CYP51, CYP19, StAR and 3β-HSD. The results showed that PUFAs significantly increased the protein levels of all of these enzymes. These results indicate that PUFAs enhance the reproductive performance of PCOS by increasing the expression of steroidogenesis enzymes, which are related to hormone secretion and ovarian functions. These findings provide evidence that a balanced n-3/n-6 PUFA ratio is beneficial for PCOS reproduction.

Importance of lipid metabolism on oocyte maturation and early embryo development: Can we apply what we know to buffalo?

The knowledge about the biological events that regulate lipid metabolism in oocytes and embryos in buffalo is scarce. Lipogenesis, lipolysis, transport and oxidation of fatty acids (FAs) occur in gametes and embryonic cells of all mammalian species, as an intrinsic component of energy metabolism. In oocytes and cumulus cells, degradation of lipids is responsible for the production of ATP that is essential for the metabolic processes that lead to oocyte maturation in in vivo and in vitro culture conditions. Similarly, throughout embryo development, blastomeres have the capacity to use exogenous and/or endogenous lipid reserves to serve as an energy source necessary for early embryonic development. In addition, supplementation of culture media with L-carnitine to promote lipid metabolism during in vitro oocyte maturation and early embryonic development leads to an improved embryo quality. The limited scientific evidence available in buffalo indicates there is relatively greater oocyte lipid content as compared with many other species that undergoes a dynamic distribution during folliculogenesis and follicle maturation and that has a positive effect on oocyte maturation and embryo development when there is L-carnitine supplementation of the media. Advances in the understanding of the biological peculiarities of lipid metabolism, and the consequences of its alteration on the quality of buffalo gametes and embryos, therefore, are necessary to design specific culture media and laboratory procedures as a strategy to increase in vitro-derived embryo production rates.

Arachidonic Acid Regulation of Intracellular Signaling Pathways and Target Gene Expression in Bovine Ovarian Granulosa Cells

Simple Summary

Arachidonic acid (AA) is one of the polyunsaturated fatty acids that presents in a very high proportion in the mammalian follicular fluid. However, the mechanism of its effects on bovine ovarian granulosa cells is not clear. In the present study, we found that arachidonic acid plays an important role in regulating cell proliferation, lipid accumulation and steroidogenesis of granulosa cells. In this sense, arachidonic acid can directly affect the functionality of granulosa cells and therefore follicular development and ovulation, which could provide useful information for future studies relating to increasing fecundity of bovine.

Abstract

In the present study, AA was used to challenge bovine ovarian granulosa cells in vitro and the related parameters of cellular and molecular biology were measured. The results indicated that lower doses of AA increased survival of bovine granulosa cells whereas higher doses of AA suppressed survival. While lower doses of AA induced accumulation of lipid droplet in granulosa cells, the higher dose of AA inhibited lipid accumulation, and AA increased abundance of FABP3, CD36 and SLC27A1 mRNA. Higher doses of AA decreased the secretion of E2 and increased the secretion of P4 accompanied by down-regulation of the mRNA abundance of CYP19A1, FSHR, HSD3B1 and STAR in granulosa cells. The signaling pathways employed by AA in the stimulation of genes expression included both ERK1/2 and Akt. Together, AA specifically affects physiological features, gene expression levels and steroid hormone secretion, and thus altering the functionality of granulosa cells of cattle.

An overview on how cumulus cells interact with the oocyte in a condition with elevated NEFA levels in dairy cows

Metabolic stress in humans and animals is associated with impaired fertility. A major characteristic of metabolic stress is elevated levels of free fatty acids (NEFAs) in blood due to mobilization of body fat reserves. Dairy cows undergo a period of metabolic stress during the peri-calving period, the so-called negative energy balance (NEB) in the early weeks postpartum. At the time of NEB, both saturated and unsaturated NEFAs are mobilized to serve as an alternative energy supply for cells, however in particular saturated NEFAs can have a detrimental effect on somatic cells. Circulating NEFAs are also reflected in the follicular fluid of ovarian follicles and hence reach the cumulus-oocyte-complex (COC), which implies a potential risk for the developing oocyte. To this end, the current review focusses on the impact of NEFAs on the quality of the oocyte.

Ovarian follicular development, hormonal and metabolic profile in prepubertal ewe lambs with moderate dietary restriction and lipid supplementation

To evaluate the effects of moderate dietary restriction and lipid supplementation on ovarian follicular development, hormonal and metabolic profile, thirty-five prepuberal ewe lambs were blocked by body weight and randomly assigned to treatments: ALUS (control) - unsupplemented-diet ad libitum (3.5% ether extract, n = 9); R-US - intake restricted to 85% of the ALUS diet (n = 9); AL-LS - lipid-supplemented-diet ad libitum (9.8% ether extract, n = 8); R-LS - intake restricted to 85% of the ALLS diet (n = 9), from 95 ± 8 days of age until estrus or 7 months of age. Lipid supplementation did not reduce dry matter intake. Daily weight gain was greater in lambs fed ad libitum. Plasma glucose was greater in the RLS treatment group, while serum insulin was less with lipid supplementation. There was a treatment by age interaction on total cholesterol, HDL cholesterol and triglyceride serum concentrations. Estrus was detected in 43% of the animals and the overall ovulation rate was 60%. The number of follicles, diameter of the largest follicle, body weight, age and serum progesterone at puberty did not differ among treatment groups. The mean diameter of the largest follicle was greater in lambs having than in those not having ovulations and increased with age in both groups. There was an interaction between the effects of occurrence of ovulation and age on the number of follicles between 3 and 5 mm and > 5 mm. Lipid supplementation and dietary restriction altered the metabolic profile in ewe lambs with no concomitant changes in values for reproductive variables.

Effects of flavonoids from Allium mongolicum Regel as a dietary additive on meat quality and composition of fatty acids related to flavor in lambs

Sixty male Small-tailed Han sheep (initial body weight: 42.5 ± 4.1 kg) were assigned randomly and averagely into four groups to evaluate effects of flavonoids extracted from Allium mongolicum Regel (AMR) on meat quality and composition of fatty acids related to flavor in longissimus dorsi muscle of lambs. Lambs of four groups were fed a basal control diet (C), and basal diet + three different amounts of flavonoids extracted from the AMR; those were 11 mg kg−1 (Flav 11), 22 mg kg−1 (Flav 22), or 33 mg kg−1 (Flav 33), respectively. Dressing percentage, loin eye area, cooking loss, and pressing loss were affected by treatments (P < 0.05). Percentage of intramuscular fat, the concentrations of eicosapentaenoic acid, C18:0, total saturated fatty acids, monounsaturated fatty acid, and 4-methyloctanoic acid in longissimus dorsi muscle were changed by treatments (P < 0.05). Addition of AMR to diet improved the meat quality and had favorable effects on fatty acid composition related to meat flavor in longissimus dorsi muscle.

Reduction in FSH Throughout the Menstrual Cycle After Omega-3 Fatty Acid Supplementation in Young Normal Weight but not Obese Women

Dietary fish oil restores ovarian function in subfertile rats, which is thought to be associated with decreased transcription of follicle-stimulating hormone (FSH) β-subunit. We have previously demonstrated a reduction in early follicular serum FSH levels in normal weight but not obese women after treatment with omega-3 polyunsaturated fatty acids (PUFA). Herein, we report the effect of supplementation with omega-3 PUFA on urinary reproductive hormones across the whole menstrual cycle. This interventional study included 17 eumenorrheic women, aged 24-41 years. One month of daily morning urine was collected before and after 1 month of omega-3 PUFA supplementation with 4 g of eicosapentaenoic acid and docosahexaenoic acid daily. Measurements included urinary FSH, luteinizing hormone (LH) and estrogen and progesterone metabolites, plasma fatty acid composition, and markers of endoplasmic reticulum stress. Compliance with dietary supplementation was verified by significantly reduced ratios of omega-6 to omega-3 PUFA for all subjects after treatment (P < .01). After 1 month of omega-3 PUFA supplementation, urinary FSH was significantly decreased in normal weight, but not obese women, in both follicular and luteal phases (-28.4% and -12.6%, respectively, both P = .04). No significant changes were seen in LH or sex steroids for either weight group. The selective and specific decrease in FSH suggests that omega-3 PUFA supplementation merits further investigation in normal weight women with decreased fertility and/or diminished ovarian reserve.

Effects of omega-3 polyunsaturated fatty acids on steroidogenesis and cellular development in PCOS rats

Polycystic ovary syndrome (PCOS) is a common endocrine disorder, which is characterized by hyperandrogenism.

Effects of supplying omega-3 polyunsaturated fatty acids to gilts after weaning on metabolism and ovarian gene expression

Omega-3 PUFA may benefit sow reproductive performance, but effects on weaned gilts are unknown. This study evaluated the effects of supplementing omega-3 PUFA to gilts after weaning on growth, metabolic markers, and gene expression of steroidogenic enzymes and hormone receptors. For 52 d, gilts in the control group were fed 100 g/d of regular diets, whereas gilts in the omega-3 group were fed 75 g/d of such diets plus 25 g/d of the microalgae Schizochytium sp. (3.5 g/d of omega-3 PUFA; n = 8 gilts/group). Blood samples were collected at day 0, day 21, and day 52. Total serum cholesterol levels were lower for the omega-3 group than for the control group (P < 0.05), but high-density lipoprotein-cholesterol levels were reduced at day 52 for both groups (P < 0.05). Gilts in the omega-3 group presented lower feed intake, better feed conversion, and less-intense immunolabeling for leptin and its receptor in the cytoplasm of oocytes included in primordial/primary follicles than gilts in the control group (P < 0.05). The expression of genes coding for cholesterol side-chain cleavage and aromatase enzymes and the LH receptor in follicular cells was lower for supplemented gilts (P < 0.05). Compared with controls, supplemented gilts presented decreased serum cholesterol levels and better feed conversion, but leptin presence and gene expression for steroidogenic enzymes and for the LH receptor were lower at ovarian level.

The consequences of porcine IVM medium supplementation with follicular fluid become reflected in embryo quality, yield and gene expression patterns

Oocyte and embryo developmental competence are shaped by multiple extrinsic and intrinsic factors. One of the most extensive research areas in the last decade is the regulation of lipid metabolism in oocytes and embryos of different species. We hypothesized that differences in developmental competence of oocytes and embryos between prepubertal and cyclic gilts may arise due to distinct fatty acid profiles in follicular fluid. We found that supplementation of oocyte maturation media with follicular fluid from prepubertal pigs affected quality and development of embryos from prepubertal pigs while embryos of cyclic pigs were not affected. PLIN2, SCD and ACACA transcripts involved in lipid metabolism were upregulated in embryos originating from oocytes of prepubertal pigs matured with autologous follicular fluid. The surface occupied by lipid droplets tend to increase in oocytes matured with follicular fluid from prepubertal pigs regardless oocyte origin. The change into follicular fluid of cyclic pigs increased the efficiency of embryo culture and improved quality, while gene expression was similar to embryos obtained from cyclic gilts. We assume that the follicular fluids of prepubertal and cyclic pigs influenced the quality of oocytes and embryos obtained from prepubertal pigs which are more susceptible to suboptimal in vitro culture conditions.

Long-chain omega-3 polyunsaturated fatty acids decrease mammary tumor growth, multiorgan metastasis and enhance survival

Epidemiological studies show a reduced risk of breast cancer (BC) in women consuming high levels of long-chain (LC) omega-3 (ω-3) fatty acids (FAs) compared with women who consumed low levels. However, the regulatory and mechanistic roles of dietary ω-6 and LC-ω-3 FAs on tumor progression, metastasis and survival are poorly understood. Female BALB/c mice (10-week old) were pair-fed with a diet containing ω-3 or an isocaloric, isolipidic ω-6 diet for 16 weeks prior to the orthotopic implantation of 4T1 mammary tumor cells. Major outcomes studied included: mammary tumor growth, survival analysis, and metastases analyses in multiple organs including pulmonary, hepatic, bone, cardiac, renal, ovarian, and contralateral MG (CMG). The dietary regulation of the tumor microenvironment was evaluated in mice autopsied on day-35 post tumor injection. In mice fed the ω-3 containing diet, there was a significant delay in tumor initiation and prolonged survival relative to the ω-6 diet-fed group. The tumor size on day 35 post tumor injection in the ω-3 group was 50% smaller and the frequencies of pulmonary and bone metastases were significantly lower relative to the ω-6 group. Similarly, the incidence/frequencies and/or size of cardiac, renal, ovarian metastases were significantly lower in mice fed the ω-3 diet. The analyses of the tumor microenvironment showed that tumors in the ω-3 group had significantly lower numbers of proliferating tumor cells (Ki67⁺)/high power field (HPF), and higher numbers of apoptotic tumor cells (TUNEL⁺)/HPF, lower neo-vascularization (CD31⁺ vessels/HPF), infiltration by neutrophil elastase⁺ cells, and macrophages (F4/80⁺) relative to the tumors from the ω-6 group. Further, in tumors from the ω-3 diet-fed mice, T-cell infiltration was 102% higher resulting in a neutrophil to T-lymphocyte ratio (NLR) that was 76% lower (p < 0.05). Direct correlations were observed between NLR with tumor size and T-cell infiltration with the number of apoptotic tumor cells. qRT-PCR analysis revealed that tumor IL10 mRNA levels were significantly higher (six-fold) in the tumors from mice fed the ω-3 diet and inversely correlated with the tumor size. Our data suggest that dietary LC-ω-3FAs modulates the mammary tumor microenvironment slowing tumor growth, and reducing metastases to both common and less preferential organs resulting in prolonged survival. The surrogate analyses undertaken support a mechanism of action by dietary LC-ω-3FAs that includes, but is not limited to decreased infiltration by myeloid cells (neutrophils and macrophages), an increase in CD3⁺ lymphocyte infiltration and IL10 associated anti-inflammatory activity.

Dietary Patterns and The Outcomes of Assisted Reproductive Techniques in Women with Primary Infertility: A Prospective Cohort Study

Background

Infertility is one of the most common challenges that women in reproductive age would encounter today. The maternal nutritional status could be a determinant of oocyte quality and embryonic growth. This study was conducted to assess the relationship between dietary patterns and reproductive outcomes in infertile women.

Materials and Methods

This prospective cohort study was conducted on 140 women with primary infertility who had referred to Isfahan Fertility and Infertility center, Isfahan, Iran. The average number of total oocytes and metaphase II oocytes, the fertilization rate, the ratio of good and bad quality embryo and biochemical and clinical pregnancy were considered as the outcomes of assisted reproductive techniques (ART). A 168-item food frequency questionnaire was used for estimating the dietary intakes during the last year. Factor analysis was used for identifying the dietary patterns and analysis of variance (ANOVA), analysis of covariance (ANCOVA), chi-square, and logistic regression analysis were used for assessing the relation between dietary patterns and ART’s outcomes.

Results

Three major dietary patterns (the healthy, western and unhealthy diet) were identified. Women with high adherence to the “healthy diet” had a higher educational level and were employed. There was a significant increase in the average number of total oocytes (P-trend=0.009) and metaphase II oocytes (P-trend=0.006) in the third tertile of “healthy diet” compared to the first tertile. Also, women with high adherence to the second tertile of “unhealthy” diet compared to the first tertile, had a significantly lower chance of getting pregnant [odds ratio (OR): 0.14, 95% confidence interval (CI): 0.3-0.7].

Conclusion

Nutrition status could affect infertility treatment outcomes. Greater adherence to the healthy diet may enhance oocyte quality and quantity. Unhealthy diet could adversely affect the chance of getting pregnant.

Linoleic (LA) and linolenic (ALA) acid concentrations in follicular fluid of prepubertal goats and their effect on oocyte in vitro maturation and embryo development

In this study we assessed the concentration of linoleic acid (LA) and linolenic acid (ALA) in follicular fluid of prepubertal goats according to follicle size (<3mm or ≥3mm) by gas chromatography and tested the addition of different LA and ALA (LA:ALA) concentration ratios (50:50, 100:50 and 200:50µM) to the IVM medium on embryo development, mitochondrial activity, ATP concentration and relative gene expression (RPL19, ribosomal protein L19; SLC2A1, facilitated glucose transporter 1; ATF4, activating transcription factor 4; GPX1, glutathione peroxidase 1; HSPA5, heat-shock protein family A 70 kDa; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; DNMT1, DNA methyltransferase 1; GCLC, glutamate-cysteine ligase catalytic subunit; SOD1, superoxide dismutase 1). Oocytes were in vitro matured, fertilised or parthenogenetically activated and zygotes were cultured following conventional protocols. LA concentration ranged from 247 to 319µM and ALA concentration from 8.39 to 41.19µM without any effect of follicle size. Blastocyst production from the different groups was: control FCS (22.33%) and BSA (19.63%), treatments 50:50 (22.58%), 100:50 (21.01%) and 200:50 (9.60%). Oocytes from the 200:50 group presented higher polyspermy and mitochondrial activity compared with controls and the rest of the treatment groups. No differences were observed in ATP concentration or relative expression of the genes measured between treatment groups. In conclusion, the low number of blastocysts obtained in the 200:50 group was caused by a high number of polyspermic zygotes, which could suggest that high LA concentration impairs oocyte membranes.

Action mechanisms of n-3 polyunsaturated fatty acids on the oocyte maturation and developmental competence: Potential advantages and disadvantages

Infertility is a growing problem worldwide. Currently, in vitro fertilization (IVF) is widely performed to treat infertility. However, a high percentage of IVF cycles fails, due to the poor developmental potential of the retrieved oocyte to generate viable embryos. Fatty acid content of the follicular microenvironment can affect oocyte maturation and the subsequent developmental competence. Saturated and monounsaturated fatty acids are mainly used by follicle components as primary energy sources whereas polyunsaturated fatty acids (PUFAs) play a wide range of roles. A large body of evidence supports the beneficial effects of n-3 PUFAs in prevention, treatment, and amelioration of some pathophysiological conditions including heart diseases, cancer, diabetes, and psychological disorders. Nevertheless, current findings regarding the effects of n-3 PUFAs on reproductive outcomes in general and on oocyte quality more specifically are inconsistent. This review attempts to provide a comprehensive overview of potential molecular mechanisms by which n-3 PUFAs affect oocyte maturation and developmental competence, particularly in the setting of IVF and thereby aims to elucidate the reasons behind current discrepancies around this topic.

Parental high dietary arachidonic acid levels modulated the hepatic transcriptome of adult zebrafish (Danio rerio) progeny

Disproportionate high intake of n-6 polyunsaturated fatty acids (PUFAs) in the diet is considered as a major human health concern. The present study examines changes in the hepatic gene expression pattern of adult male zebrafish progeny associated with high levels of the n-6 PUFA arachidonic acid (ARA) in the parental diet. The parental generation (F₀) was fed a diet which was either low (control) or high in ARA (high ARA). Progenies of both groups (F₁) were given the control diet. No differences in body weight were found between the diet groups within adult stages of either F₀ or F₁ generation. Few differentially expressed genes were observed between the two dietary groups in the F₀ in contrast to the F₁ generation. Several links were found between the previous metabolic analysis of the parental fish and the gene expression analysis in their adult progeny. Main gene expression differences in the progeny were observed related to lipid and retinoid metabolism by PPARα/RXRα playing a central role in mediating changes to lipid and long-chain fatty acid metabolism. The enrichment of genes involved in β-oxidation observed in the progeny, corresponded to the increase in peroxisomal β-oxidative degradation of long-chain fatty acids in the parental fish metabolomics data. Similar links between the F₀ and F₁ generation were identified for the methionine cycle and transsulfuration pathway in the high ARA group. In addition, estrogen signalling was found to be affected by parental high dietary ARA levels, where gene expression was opposite directed in F₁ compared to F₀. This study shows that the dietary n-3/n-6 PUFA ratio can alter gene expression patterns in the adult progeny. Whether the effect is mediated by permanent epigenetic mechanisms regulating gene expression in developing gametes needs to be further investigated.

Effects of dietary omega-3 PUFAs on growth and development: Somatic, neurobiological and reproductive functions in a murine model

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs) are relevant to fetal and infant growth and development. Objective: to assess whether long-term exposure to dietary ω-3 PUFA imbalance alters pre- and/or postnatal pups' development and reproductive function later in life. Mice dams were fed with ω-3 PUFA Control (soybean oil, 7%), Deficient (sunflower oil, 7%) or Excess (blend oil; 4.2% cod-liver+2.8% soybean) diet before conception and throughout gestation-lactation and later on, their pups received the same diet from weaning to adulthood. Offspring somatic, neurobiological and reproductive parameters were evaluated. Excess pups were lighter during the preweaning period and shorter in length from postnatal day (PND) 7 to 49, compared to Control pups (P<.05). On PND14, the percentage of pups with eye opening in Excess group was lower than those from Control and Deficient groups (P<.05). In Excess female offspring, puberty onset (vaginal opening and first estrus) occurred significantly later and the percentage of parthenogenetic oocytes on PND63 was higher than Control and Deficient ones (P<.05). Deficient pups were shorter in length (males: on PND14, 21, 35 and 49; females: on PND14, 21 and 42) compared with Control pups (P<.05). Deficient offspring exhibited higher percentage of bending spermatozoa compared to Control and Excess offspring (P<.05). These results show that either an excessively high or insufficient ω-3 PUFA consumption prior to conception until adulthood seems inadvisable because of the potential risks of short-term adverse effects on growth and development of the progeny or long-lasting effects on their reproductive maturation and function.