Vitamin C and vitamin E supplementation alleviates oxidative stress induced by dexamethasone and improves fertility of breeder roosters

Astaxanthin Improved the Quality of Hu Ram Semen by Increasing the Antioxidant Capacity and Mitochondrial Potential and Mitigating Free Radicals-Induced Oxidative Damage

The objective of this research was to investigate the effect of astaxanthin supplementations of semen extender on the quality of Hu ram semen after up to five days of preservation at 4 °C. Semen samples were collected from five healthy Hu rams using an artificial vagina during breeding season (April to August 2023) and diluted with a basic extender supplemented with control (0), 1 µM, 2 µM, 3.5 µM, or 4.5 µM of AXT. Overall, 170 semen ejaculate samples (34 repetitions) from five healthy Hu rams were used in our research study. The results revealed that the addition of AXT (3.5 µM) significantly (p ≤ 0.05) increased the sperm kinematic indexes (T.M%, P.M%, MAD%, STR%, and LIN %), sperm viability, plasma membrane integrity, acrosome integrity, total antioxidant content (T-AOC), and mitochondrial membrane potential (MMP) of the Hu rams spermatozoa after up to five days of preservation at 4 °C. Contrary to that, the addition of the best concentration of AXT (3.5 µM) to the semen extender significantly (p ≤ 0.05) reduced the reactive oxygen species (ROS) and malondialdehyde (MDA) concentration of Hu ram semen. In conclusion, the results of the current study indicate that the addition of a semen extender with AXT improves the quality of Hu ram spermatozoa by increasing the total antioxidant capacity (T-AOC) and mitochondrial membrane potential (MMP). On the other hand, reducing free radicals induced oxidative (ROS) and per oxidative (MDA) damage to Hu ram semen.

Physiological roles of propolis and red ginseng nanoplatforms in alleviating dexamethasone-induced male reproductive challenges in a rat model

BACKGROUND

Red ginseng and propolis are well-known antioxidants that have been related to a reduction in oxidative stress.

OBJECTIVE

This study evaluated the efficiency of red ginseng and propolis, either in powder or as nano-forms against dexamethasone-induced testicular oxidative challenges in adult male albino rats.

METHODS

Forty rats were divided into 8 equal groups including control negative group that was given vehicle (DMSO), control positive group that was administered dexamethasone in addition to the nano-propolis, nano-ginseng, nano-propolis + dexamethasone, nano ginseng+dexamethasone, propolis+dexamethasone and ginseng + dexamethasone groups. Serum, semen and tissue samples were obtained.

RESULTS

Lower testosterone levels, higher levels of MDA, and lower levels of total antioxidant capacity in serum, as well as impaired semen quality and a disturbed histopathological picture of both the testis and seminal glands, were all observed as significant negative effects of dexamethasone. These findings were confirmed by lower gene expression profiles of CYP11A1, StAR, HSD-3b, Nrf-2 and ACTB-3b in testicular and seminal gland tissues. The most powerful anti-dexamethasone effects were obtained with either propolis in nanoform or conventional ginseng.

CONCLUSION

Propolis nano-formulation and ginseng in conventional form could be considered excellent candidates to ameliorate the oxidative stress provoked by dexamethasone, however, neither nano-ginseng nor conventional propolis showed such effects.

Improvement of diluted semen from Muscovy (Cairina moschata) drakes by the addition of water-soluble antioxidants

The aim of this study was to evaluate the effect of antioxidant supplementation in diluted semen from Muscovy drakes after the induction of oxidative stress (OS) on the sperm motility, kinematic parameters and biochemical markers - lipid peroxidation (LPO) levels and total glutathione (tGSH) concentration. The pooled semen was distributed equally into three parts, diluted (1:3 v/v) with IMV Canadyl, HIA-1 or AU, and stored at 4°C for 6 h. Later, the semen was equilibrated at 20-25°C for 15 min, and divided in Eppendorf tubes. The sperm samples (final concentration of 50 × 106 sperm cells/mL per sample) were incubated at 37°C for 30 min in the absence (-) or presence (+) of 0.1 mM FeSO4  + 0.5 mM H2 O2 (Fenton system) and the following combinations of antioxidants: ascorbic acid + Trolox (A + T); ascorbic acid + Desferal (A + D); Trolox + Desferal (T + D) and ascorbic acid + Trolox + Desferal (A + T + D), all of them in a final concentration of 0.1 mM. Thus, the total number of samples was 30 and in each one, the sperm motility, velocity parameters, LPO and tGSH were determined. The motility and kinematic parameters of the diluted semen with added antioxidants were restored by up to 20% after inducing OS via the Fenton reaction. Dual combinations of antioxidants (A + T, A + D, and T + D) lowered LPO levels, but not equally across different extenders. After the induction of OS, the tGSH levels in diluted semen with IMV-Canadyl were not affected by the added antioxidants. Whereas antioxidant combinations in diluted semen with HIA-1 or AU had a beneficial effect and partially restored tGSH levels. In conclusion, the results showed that the extender IMV-Canadyl is well balanced and protected the Muscovy semen under OS conditions, while the other two extenders HIA-1 and AU can be improved by adding antioxidants.

Mitochondria-targeted antioxidant "MitoQ" improves rooster's cooled sperm quality indicators and reproductive performance

The cell membrane of rooster sperm is sensitive to cold due to the high content of polyunsaturated fatty acids, which are very susceptible to lipid peroxidation. The present study was conducted to determine the effect of different concentrations of the mitochondrial-targeting antioxidant "MitoQ" on sperm quality and fertility potential of chilled semen in roosters. Semen samples were collected from 10 roosters, diluted in Lake extender, assigned into 5 groups according to MitoQ concentrations (0, 1, 10, 100 and 1000 nM MitoQ) and stored at 5 ^°C up to 48 h. Motility, mitochondrial activity, viability, membrane integrity, and lipid peroxidation were assessed at 0, 24, and 48 h of cold storage periods. In addition, the fertility potential was assessed using 24 h-cooled semen samples. Our results showed that extender supplementation with MitoQ had no effect (P > 0.05) on chilled semen samples quality parameters at time 0, while at times 24 and 48 h storage, samples contained 100 nM MitoQ presented higher (P ≤ 0.05) total motility, progressive motility, viability and membrane integrity compared to the other groups. In addition, semen samples containing 10 and 100 nM MitoQ showed higher (P ≤ 0.05) mitochondrial activity and lower (P ≤ 0.05) lipid peroxidation than other groups at 24 and 48 h storage. Fertility rate was higher (P ≤ 0.05) when the hens were artificially inseminated with 24 h-chilled semen samples containing 100 nM MitoQ. In conclusion, supplementing Lake Extender with 100 nM MitoQ could be a helpful strategy to preserve chilled semen quality and fertility potential in the rooster.

Enhancement of sperm quality and fertility-related parameters in Hubbard grandparent rooster fed diets supplemented with soybean lecithin and vitamin E

The purpose of this study was to investigate the effect of dietary supplementation of different levels of soybean lecithin and vitamin E on semen quality parameters and some reproductive hormones in Hubbard grandparent roosters. The experiment was conducted in a 3 × 2 factorial arrangement with 3 levels of soybean lecithin (0, 1, and 2%) and 2 levels of vitamin E (0 and 300 mg/kg). Semen samples were collected on d 0, 20, 40 and 60 of the experiment and analyzed. Adding 1% soybean lecithin and vitamin E into the diet increased semen volume and sperm concentration, membrane integrity and viability (P < 0.05). Supplementing diets with 1 or 2% lecithin in addition to vitamin E significantly improved total motility and progressive motility (P < 0.05). Vitamin E significantly increased the amplitude of lateral head displacement (ALH) of sperm (P < 0.05). Although there was no effect on LH and FSH when diets were supplemented with vitamin E and 1 or 2% lecithin, testosterone concentration was increased (P < 0.05). Malondialdehyde (MDA) concentration was significantly lower in all 3 treatments containing vitamin E (P < 0.05). It can be concluded that supplementation of rooster diets with vitamin E and 1% lecithin can improve fertility related parameters in Hubbard grandparent roosters.

Effect of vitamin E supplementation on chicken sperm quality: A meta-analysis

Background and Aim:

Among several factors, the sperm quality of poultry is affected by the rooster’s body size and the availability of antioxidants like vitamin E. This study aimed to determine the effect of dietary vitamin E supplementation on rooster sperm quality through a meta-analysis.

Materials and Methods:

After verification and evaluation, a total of 19 articles were included in this study. Data, including dietary vitamin E, semen volume, concentration, total sperm cells, pH, motility, viability, percentage of dead and abnormal sperm, vitamin E sperm content, malondialdehyde (MDA) content, and testosterone levels, were tabulated in a database; these were subsequently analyzed using mixed modeling with vitamin E dose as a fixed effect and study identity as a random effect.

Results:

Dietary supplementation level of vitamin E significantly (p<0.001) affected sperm concentration, significantly affected motility (p<0.001), significantly affected sperm vitamin E (p<0.001), significantly affected viability (p<0.001), and significantly affected chicken sperm fertility (p=0.001). Vitamin E administration also significantly reduced the number of sperm cell deaths (p<0.001); however, increased dietary levels of vitamin E did not affect semen volume (p=0.853), pH (p=0.951), MDA (p=0.542), the percentage of abnormal sperm cells (p=0.343), nor testosterone levels (p=0.063).

Conclusion:

Dietary vitamin E supplementation is recommended for male chickens since it generally enhances the quality of their sperm.

Supplementation of Avian Semen Extenders with Antioxidants to Improve Semen Quality-Is It an Effective Strategy?

Oxidative stress in sperm is a phenomenon related to the increasing rate of oxidation of cellular components and the excessive production of reactive oxygen species (ROS). The high content of polyunsaturated fatty acids in bird sperm cell membranes renders these cells particularly susceptible to lipid peroxidation (LPO). Therefore, to ensure the proper functioning of cells, it is necessary to have a balance between the formation of ROS and the protective action of the antioxidant system. This review aims firstly to briefly introduce the antioxidant system characteristics of avian semen. Secondly, we summarize the recent knowledge regarding progress in extender supplementation using antioxidants and other compounds to improve avian semen quality parameters and fertility rates. The review focuses on enzymes, vitamins, amino acids, proteins, some plant extracts, and other compounds that can be used to supplement the extenders to reduce the formation of oxidants in poultry semen and maintain its quality and enhance its fertility.

Does ergothioneine and thawing temperatures improve rooster semen post-thawed quality?

The present study focuses on the effect of different levels of ergothioneine and thawing temperature on rooster semen cryopreservation. Semen was diluted in Lake extender containing ergothioneine at 5, 10, 15, and 20 µM and cryopreserved. Two thawing temperatures (37°C for 30 s and 60°C for 5 s) were consequently examined. Sperm motility parameter, membrane integrity, abnormal morphology, viability, apoptotic status, mitochondria activity, and lipid peroxidation were determined after freeze-thaw process. Ergothioneine levels of 5 and 10 µM led to higher (P < 0.05) total motility (66.58 ± 1.44 and 72.11±1.44, respectively) and average path velocity (VAP) (34.54 ± 0.89, 37.28 ± 0.89, respectively). Higher (P < 0.05) significant membrane integrity and mitochondria activity after freeze-thawing were observed in the groups supplemented with 10 µM ergothioneine (68.62 ± 1.24 and 69.12 ± 1.26, respectively). Also, 5 and 10 µM of ergothioneine led to the lowest significant percentage of apoptotic and dead sperm. The total motility and progressive motility resulted in significantly (P < 0.05) higher amount when sperm were thawed with 60°C (60.58 ± 0.91 and 24.76 ± 0.53, respectively) compared to thawed sperm in 37°C. The membrane integrity, viability and mitochondria activity led to significantly (P < 0.05) higher when sperm were thawed with 60°C (58.2 ± 0.78, 63.21 ± 0.80 and 56.85 ± 0.79, respectively). It could be concluded the addition of 5 and 10 µM ergothioneine in the semen extender and thawing temperature at 60˚C in 5 s can be an efficient strategy to preserve rooster cryopreserved semen quality.

Dietary ascorbic acid and betaine improve stress responses, testosterone levels and some sexual traits in male Japanese quails during the dry season

The experiment investigated the effects of dietary ascorbic acid and betaine stress responses, serum testosterone levels, and some sexual traits in male Japanese quails during the dry season. A total of 240 male Japanese quails (14 days old) were used and randomly assigned to four groups, each group has three replicates (n = 20). Birds in treatment groups were fed ascorbic acid (AA); betaine (BET); and AA + BET in their diets, whereas the control birds were fed only basal diet. Environmental conditions were predominantly outside thermoneutral zone for Japanese quails. Dietary AA ± BET increased (p < .05) serum catalase, reduced glutathione and testosterone, but lowered (p < .05) cortisol levels when compared with control group. Supplemental AA, BET, or AA + BET enhanced (p < .05) cloacal gland size and sexual traits. In conclusion, dietary AA and BET improved stress responses, serum testosterone levels, and some sexual traits in male Japanese quails during the dry season.

Effects of dietary alpha-lipoic acid supplementation on the seminal parameters and fertility potential in aging broiler breeder roosters

High levels of polyunsaturated fatty acids in avian sperm cause more susceptibility to lipid peroxidation. Aging in roosters reduces the antioxidant capacity of sperm and thus fertility. The purpose of this study was to investigate the effects of different levels of alpha-lipoic acid (ALA) as a feed supplement to improve the semen quality and fertility parameters of aged broiler breeder roosters and identification of its most effective level. A total of forty-two roosters at 45 wk of age were randomly assigned to 7 treatments (0, 15, 40, 70, 95, 120, and 145 mg ALA/bird per day) for 8 wk. Semen parameters and body weight were assessed biweekly, and testosterone plasma levels were determined in the 8th wk of the experimental period. Artificial insemination was performed at the end of the experiment to evaluate the fertility potential. The dietary administration of ALA had no significant effects on body weight, semen volume, average path velocity, linearity, straightness, wobble, the amplitude of lateral head displacement, beat-cross frequency, sperm concentration, morphology, plasma testosterone level, fertility, or hatchability (P > 0.05). Alpha-lipoic acid supplementations resulted in a significant decrease in seminal malondialdehyde concentration and immotile (type D) sperms (P < 0.05). The total motility, progressive motility (types A + type B sperms), curvilinear velocity, straight-line velocity, viability, and membrane integrity of sperm improved with ALA dietary supplementations (P < 0.05). With increasing ALA levels, improvement in semen parameters had an incremental trend until the level of 95 mg ALA. Thus, 95 mg dietary ALA as an antioxidant supplement can improve semen quality of aging breeder roosters while higher doses resulted in no further improvement.

Protective effect of vitamin C and lycopene on the in vitro fertilization capacity of sex-sorted bull sperm by inhibiting the oxidative stress

The fertilization capacity of sex-sorted sperms is seriously decreased, which inhibits its wide application. However, little information is still available about the effect of vitamin C (VC) and lycopene (Lyc) on the fertilization capacity of sex-sorted bull sperm. In this study, the washing medium and fertilization medium of sex-sorted sperm from three bull individuals were supplemented with different concentrations of VC (0, 1 × 10^-3 , 1 × 10^-4 , 1 × 10^-5 , 1 × 10^-6  M) or Lyc (0, 1 × 10^-4 , 1 × 10^-5 , 1 × 10^-6 , 1 × 10^-7 ). After washing twice and incubation for 1.5 hr, the malondialdehyde (MDA) level, phosphatidylserine (PS) translocation, membrane potential (Δψm) and IVF (in vitro fertilization) ability of sex-sorted sperm were investigated. For the sex-sorted sperm of bulls A, B and C, 1 × 10^-3  M VC or 1 × 10^-4  M Lyc treatment significantly decreased their MDA levels and PS translocation and increased their Δψm levels and cleavage rates after IVF. When blastocysts were concerned, 1 × 10^-4  M Lyc significantly improved the blastocyst rates and their IFN-tau expression of bulls A and C. In conclusion, supplementation of 1 × 10^-3  M VC or 1 × 10^-4  M Lyc in washing and fertilization medium contributed greatly to improving the fertilization capacity of sex-sorted bull sperm during IVF procedure.

Effect of astaxanthin nanoparticles in protecting the post-thawing quality of rooster sperm challenged by cadmium administration

The protective role of astaxanthin nanoparticles (Ast NPs, 25 mg/kg p.o) against cadmium (Cd, 1 mg/100 g b.w. SC), a known inductor of lipid peroxidation and changes in the antioxidant defense system in the Ross 308 breeder roosters sperm, was examined. Sperm motility (computer-assisted sperm motility analysis), membrane integrity (hypoosmotic swelling test), viability, total abnormality, and enzymatic parameters were assessed after thawing. The testis/body weight (mg/kg) ratio and HE staining results of testis were also performed. The obtained results showed that Cd induced detrimental effects on testis and sperm, while Cd treated by Ast NPs (Cd Ast) diminished this change compared to the Cd group. Cd-treated group resulted in significantly (P < 0.05) lowest total (37.29 ± 2.46) and progressive (5.84 ± 0.47) motility and decreased antioxidant enzyme activity (CAT, TAC, and GPx), as well as producing a significant (P < 0.05) decrease in testis weight (mg) compared to the control group. Treatment with Ast NPs (Ast NPs + Cd) had reversed Cd-induced changes in the antioxidant defense system and significantly prevented Cd-induced testis damage. In conclusion, the results of our work suggest that Ast NPs at 25 mg/kg act as a potent antioxidant in protecting rooster testes against oxidative stress induced by Cd.

Oxygenic metabolism in nutritional obesity induced by olive oil. The influence of vitamin C

Obesity is a medical and sociological problem of great importance due to the high percentage of people affected and the important health consequences that it involves. Most cases of obesity are related to an inadequate diet, rich in fats, which could lead to changes in the patient's oxygenic metabolism. That is why this study has been proposed to evaluate how some aspects of oxygenic metabolism are affected in a nutritional experimental model, with a controlled hyperlipidic liquid diet based on olive oil, and the effect of the antioxidant vitamin C on these conditions. Wistar rats were divided into four groups which received a control and hyperlipidic liquid diet for 30 days, with or without a vitamin C supplement (CO, COC, HO and HOC). First of all the body and fat tissue development was measured in the four groups. Our results showed that the excessive intake of nutritional and healthy fat such as olive oil did not prevent the appearance of obesity and the supplementation with vitamin C did not have a protective effect on body and fat development. The study of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) in total liver, liver cytosol, abdominal white fat, brown fat and blood cells showed that vitamin C could have different selectivities and affinities for different enzymes and compartments/tissues of the body. Finally, the effect of vitamin C on various metabolic parameters (glucose, pyruvate, lactate, LDH, ATP, acetoacetate and beta-hydroxybutyrate) provided positive protection against oxidative stress especially under hyperlipidic conditions. All things considered, the present study concludes that vitamin C treatment could protect Wistar rats from the oxidative stress impairment induced by obesity generated by an excessive intake of fats.

Weeping forsythia extract alleviates dexamethasone-induced oxidative injury of breast muscles in broilers

Antioxidants have been always used to improve post-slaughter meat quality in broilers subjected to stress. Forsythia suspensa extract (FSE), a traditional Chinese herbal medicine, is generally regarded as a natural source of antioxidants. Therefore, the objective of this study was to test the hypothesis that FSE could protect post-slaughter breast muscles against oxidative injury induced by dexamethasone (DEX) mimicking chronic physiological stress in poultry production. Average daily gain and feed efficiency of poultry were suppressed by DEX and improved by FSE (P < 0.05). Dexamethasone caused the decrease in the redness value and the increase in the lightness and yellowness values and drip loss of the breast muscles (P < 0.05), and FSE had the converse effects (P < 0.05). Dietary FSE supplementation decreased monounsaturated fatty acid (FA) and increased polyunsaturated FA in breast muscles of broilers (P < 0.05). In addition, FSE decreased malondialdehyde and carbonyl content in the breast muscles of DEX-treated broilers (P < 0.05). The inhibition of 1,1-diphenyl-2-picryl-hydrazyl in the breast muscles was decreased by DEX and increased by FSE (P < 0.05). Total-antioxidant capacity and glutathione peroxidase activity in the breast muscles were decreased in birds subjected to DEX and increased in birds supplemented with FSE (P < 0.05). Totally, DEX suppressed growth performance and induced breast muscle oxidative injury in broilers, and FSE supplementation improved antioxidant capacity to attenuate these adverse effects. Therefore, FSE could be a potential natural antioxidant to alleviate oxidative injury of the breast muscles in broilers and to improve the meat quality for human consumption.

Use of supplemental dietary coenzyme Q10 to improve testicular function and fertilization capacity in aged broiler breeder roosters

In numerous studies it has been suggested that targeting mitochondria with specific compounds could efficiently inhibit various conditions associated with oxidative stress. The treatment of aged roosters with compounds such as coenzyme Q10 (CoQ10), may improve their reproductive performance by providing protection from oxidative stress. Therefore, this study was performed to assess the effect of supplemental dietary CoQ10 on the testicular function and fertility of aged broiler breeder roosters. A total of 36 roosters)47 weeks of age) were randomly divided into dietary treatments containing either 0, 300 or 600 mg CoQ10/kg diet. Three birds were allocated to each of four replicate groups in each dietary treatment. Between 47 and 54 weeks of age, ejaculates were obtained weekly from the three roosters in each replicate group. Samples in a replicate were pooled and analyzed as a single sample. Between 51 and 54 weeks of age, seminal plasma total antioxidant capacity (TAC), alanine amino transferase (ALAT) and aspartate amino transferase (ASAT) levels were assessed. Fertility, hatchability, and sperm penetration (SP) rates were likewise evaluated. Seminal volume, sperm concentration, sperm plasma membrane functionality, sperm plasma membrane integrity, seminiferous tubule diameter and seminiferous epithelium thickness exhibited quadratic increases in response to increasing levels of dietary CoQ10. Respectively, the 429.19, 433.33, 464.50, 613.50, 392.78 and 447.99 mg/kg dietary concentrations of CoQ10 provided the best results for each of the aforementioned variables. Also, other seminal traits, as well as testosterone concentration, fertility, and SP rates, displayed linear increases in response to the increasing levels of CoQ10. Dietary supplementation of CoQ10 linearly decreased seminal plasma ALAT and ASAT and linearly increased seminal plasma TAC. In conclusion, CoQ10 supplementation in the diet (a minimum of 300 mg CoQ10/kg diet) has the potential to improve the reproductive performance of aged broiler breeder roosters.

An overview of two decades of diet restriction studies using Drosophila

Dietary restriction (DR) is a potent forerunner in aging studies capable of influencing lifespan and improving health in various model organisms even in their old age. Despite the importance of protein and carbohydrates in the diet (regulation of fecundity and body maintenance respectively), different ratio based combinations of these components has played a major role in lifespan extension studies. In spite of differences existing in dietary protocols across laboratories, diet manipulations have evolved as a major area of research in Drosophila lifespan studies, prominently shedding light on the multi-faceted process over the last two decades. Here, we review various advances and technicalities involved in understanding the DR-mediated lifespan alongside discussing the pros and cons of various existing approaches/diets used across labs. The current review also focuses on the importance of life-stage specific DR implementation and their influence on the life-history traits including lifespan and fecundity, by taking examples of results from different studies comprising diet dilution, calorie restriction, protein restriction, carbohydrate: protein ratios and the modulations in various minor diet components. We thereby intend to gather the major advances made in these fields alongside reviewing the practical implementations that need to be made to get a better view of the DR-mediated lifespan studies.

Identification and expression analysis of alpha tocopherol transfer protein in chickens fed diets containing different concentrations of alpha-tocopherol

Among the eight forms of vitamin E, the liver preferentially releases α-tocopherol into the circulation and it is distributed to the non-liver tissues. In the hepatocytes, alpha tocopherol transfer protein (TTPA) specifically recognizes α-tocopherol with 2R-configuration and facilitates its intracellular transfer. The identification and characterization of TTPA expression have not been demonstrated in avian species. Therefore, the objectives of this study were to identify avian TTPAs, to compare the sequence conservation, phylogenetic relationship, protein interactions, and disease associations of chicken TTPA with those of human and vertebrate TTPA, and to characterize the tissue expression of the TTPA gene in chickens fed diets supplemented with different amounts of α-tocopherol. Our results suggest that the chicken TTPA was highly conserved with the human and vertebrate TTPA, and consisted of a cellular retinaldehyde binding protein and TRIO guanine exchange factor (CRAL_TRIO) domain. Feeding diets supplemented with increasing amounts of α-tocopherol (25 IU/Kg, 50 IU/Kg, or 100 IU/Kg) to broiler chickens had no effects on growth performance compared with feeding basal diets containing no supplemental α-tocopherol. The expression of TTPA gene was detected high in the liver of chickens in response to dietary α-tocopherol concentrations, whereas its expression was very low or undetectable in the non-liver tissues. In conclusion, the chicken TTPA protein sequence is highly conserved with other avian and vertebrate TTPA protein sequences. The higher expression of TTPA gene in the chicken liver in response to dietary α-tocopherol concentrations may suggest its crucial role in transporting α-tocopherol in the chicken liver.

Effect of vitamin A and vitamin C on attenuation of ivermectin-induced toxicity in male Wistar rats

An in vivo study was performed to assay the effects of ivermectin on adult male Wistar rats. Twenty-five male Wistar rats aged 6 to 8 weeks and weighing 150-250 g were divided into five groups of five animals each for the purpose of this study. The groups received ivermectin; a mixture of ivermectin and vitamin A; a mixture of ivermectin and vitamin C; and a mixture of ivermectin, vitamin A, and vitamin C, respectively. One group served as the control group and was treated with double-distilled water. The treatment was carried out once a week for 3 weeks. The results of the study revealed that the animals were less affected as detected by slight changes in the body weight, stress oxidative parameters, serum levels of liver enzymes, kidney function indexes, cell blood counts, and sperm analysis upon exposure to ivermectin. Nevertheless, the use of vitamins A and C might have a promising effect against oxidant-antioxidant imbalance. Although, the administration of free ivermectin has fewer reactions on mammals, use of the drug supplemented with antioxidants such as vitamins A and C moderates its effects.

Di-(2-ethylhexyl) phthalate (DEHP)-induced testicular toxicity through Nrf2-mediated Notch1 signaling pathway in Sprague-Dawley rats

Di-(2-ethylhexyl) phthalate (DEHP) is an environmental endocrine disruptor widely used in China that is harmful to the male reproductive system. Many studies have shown that DEHP causes testicular toxicity through oxidative stress, but the specific mechanism is unknown. Because the Notch pathway is a key mechanism for regulating cell growth and proliferation, we investigated whether Notch is involved in DEHP-induced testicular toxicity and whether vitamins E and C could rescue testicular impairment in Sprague-Dawley (SD) rats. Compared with the control group, we found that DEHP exposure induced testicular toxicity through oxidative stress injury, and it decreased the testosterone level (P < .01) and upregulated nuclear factor-erythroid 2 related factor (Nrf2) expression (P < .01). Therefore, because oxidative stress might be the initiating factor of DEHP-induced testicular toxicity, treatment with the antioxidant vitamins E and C activated the Notch1 signaling pathway in the testis and in Leydig cells. Treatment with vitamins E and C normalized the oxidative stress state after DEHP exposure and restored testicular development to be similar to the control group. In summary, antioxidant vitamins E and C may be used to treat DEHP-induced testicular toxicity.

Enhancement of sperm motility and viability by turmeric by-product dietary supplementation in roosters

Improving sperm motility and viability are major goals to improve efficiency in the poultry industry. In this study, the effects of supplemental dietary turmeric by-product (TBP) from commercial turmeric production on sperm motility, viability, and antioxidative status were examined in domestic fowl. Mature Rhode Island Red roosters were divided into two groups - controls (groupC) without TBP administration and test subjects (groupT) fed a basal diet supplemented with 0.8g of TBP/day in a temperature-controlled rearing facility (Experiment 1) and 1.6g/day under heat stress (Experiment 2) for 4 weeks. In Experiment 1, TBP dietary supplementation increased the sperm motility variables straight-line velocity, curvilinear velocity, and linearity based on a computer-assisted semen analysis, 2 weeks following TBP supplementation. In Experiment 2, using flow cytometry, sperm viability at 3 and 4 weeks following TBP supplementation was greater in Group T than C, and this increase was consistent with a reduction in reactive oxygen species (ROS) production at 2 and 4 weeks. The results of both experiments clearly demonstrate that dietary supplementation with TBP enhanced sperm motility in the controlled-temperature conditions as well as sperm viability, and reduced ROS generation when heat stress prevailed. Considering its potential application in a range of environments, TBP may serve as an economical and potent antioxidant to improve rooster fertility.

Glucocorticoids and Reproduction: Traffic Control on the Road to Reproduction

Glucocorticoids are steroid hormones that regulate diverse cellular functions and are essential to facilitate normal physiology. However, stress-induced levels of glucocorticoids result in several pathologies including profound reproductive dysfunction. Compelling new evidence indicates that glucocorticoids are crucial to the establishment and maintenance of reproductive function. The fertility-promoting or -inhibiting activity of glucocorticoids depends on timing, dose, and glucocorticoid responsiveness within a given tissue, which is mediated by the glucocorticoid receptor (GR). The GR gene and protein are subject to cellular processing, contributing to signaling diversity and providing a mechanism by which both physiological and stress-induced levels of glucocorticoids function in a cell-specific manner. Understanding how glucocorticoids regulate fertility and infertility may lead to novel approaches to the regulation of reproductive function.

Evaluation of Methanol Induced Free Radicals in Mice Liver

Methanol induced oxidative stress (OS) models in mice were successfully established and evaluated by the electron paramagnetic resonance (EPR) spin trapping technique. The capacity for removal of reactive oxygen species (ROS) free radicals by rhubarb and vitamin C (Vc) as candidate materials was also investigated. EPR was employed to determine the free radicals generated from a spin trapping agent, α-phenyl-N-tert-butylnitrone (PBN), that reacted with the ROS. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), and the level of malondialdehyde (MDA) were also evaluated by enzyme assays. The results indicated that methanol clearly promoted the generation of ROS free radicals in the liver of mice. The activity of SOD and GSH-PX was reduced significantly, although the level of MDA was increased as a result of the harmful effect of methanol. In addition, rhubarb and Vc exhibited a protective effect on the mice liver under acute OS.