Tocopherol-stripped Corn Oil Research Articles

Prenatal exposure to low-dose bisphenol A disrupts hippocampal DNA methylation and demethylation in male rat offspring.

Earlier research has demonstrated that developmental exposure to bisphenol A (BPA) has persistent impacts on both adult brain growth and actions. It has been suggested that BPA might obstruct the methylation coding of the genes in the brain. In this study, the methylation changes in the hippocampus tissue of male rat pups were examined following prenatal BPA exposure. Pregnant Sprague-Dawley rats were treated with either vehicle (tocopherol-stripped corn oil) or BPA (4, 40, or 400μg/kg·body weight/day) throughout the entire duration of gestation and lactation. At 3weeks of age, the male rat offspring were euthanized, and the hippocampus were dissected out for analysis. The expression levels of DNA methyltransferases (DNMT1, DNMT3A, and DNMT3B) and DNA demethylases (TET1, Gadd45a, Gadd45b, and Apobec1) were analyzed in the hippocampus by means of quantitative real-time polymerase chain reaction and Western blotting, respectively. The results showed that prenatal exposure to BPA upregulated the expression of enzymes associated with DNA methylation and demethylation processes in the hippocampus of male rat offspring. These findings suggest that prenatal exposure to a low dose of BPA could potentially disrupt the balance of methylation and demethylation in the hippocampus, thereby perturbing epigenetic modifications. This may represent a neurotoxicity mechanism of BPA.

In utero bisphenol A exposure disturbs germ cell cyst breakdown through the PI3k/Akt signaling pathway and BDNF expression

PurposeTo determine the influence of the environmental endocrine disruptor bisphenol A (BPA) on germ cell cyst breakdown and explore the possible mechanisms regulating this activity. MethodsBPA (2 μg/kg/d or 20 μg/kg/d) or tocopherol-stripped corn oil (vehicle control) was administered to pregnant mice by gavage at gestational day 11, and the offspring (prenatally treated mice) were sacrificed and ovariectomized at postnatal day (PND) 4 and PND22. Ovarian morphology was documented in the first filial (F1) generation female offspring, and the follicles were analyzed and classified morphologically on PND 4. To discover differentially expressed genes and associated target pathways, we used RNA-seq, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and Gene Ontology (GO) analysis. The mRNA expression of key steroid hormone synthesis-related genes was evaluated by Q-PCR in forskolin-induced KGN cells. Western blotting (WB) and qRTPCR were used to determine the protein and gene expression levels of brain-derived neurotrophic factor (BDNF). ResultsBPA, a typical endocrine disrupting chemical (EDC), decreased the expression of the key steroid hormone synthesis-related genes P450scc and aromatase, while the expression of Star increased significantly and caused no significant difference in the expression of Cyp17a1 or HSD3β in forskolin-induced KGN cells. Moreover, we confirmed that in utero exposure to environmentally relevant concentrations of BPA (2 μg/kg/d and 20 μg/kg/d) could significantly disrupt germ cell cyst breakdown, leading to the generation of fewer primordial follicles than in the control group. The factors mediating the inhibitory effects included the PI3K-Akt signaling pathway and a significant downregulation of BDNF. ConclusionsThese findings indicate that in utero exposure to BPA at low doses, which are lower than recommended as ‘safe’ dosages, may influence the formation of primordial follicles by inhibiting the expression of steroid hormone synthesis-related genes and partly by regulating the BDNF-mediated PI3K/Akt pathway.

Early postnatal exposure to di(2-ethylhexyl) phthalate causes sex-specific disruption of gonadal development in pigs

Di(2-ethylhexyl) phthalate (DEHP) is a chemical commonly used as a plasticizer to render polyvinyl chloride products more durable and flexible. Although exposure to DEHP has raised many health concerns due to the identification of DEHP as an endocrine disruptor, it is still used in consumer products, including polyvinyl chloride plastics, medical tubing, car interiors, and children’s toys. To investigate the impact of early life exposure to DEHP on the ovary and testes, newborn piglets were orally dosed with DEHP (20 or 200 mg/kg/day) or vehicle control (tocopherol-stripped corn oil) for 21 days. Following treatment, ovaries, testes, and sera were harvested for histological assessment and measurement of steroid hormone levels. In male piglets, progesterone and pregnenolone levels were significantly lower in both treatment groups compared to control, whereas in female piglets, progesterone was significantly higher in the 20 mg group compared to control, indicating sex-specific effects in a non-monotonic manner. Follicle numbers and gene expression of steroidogenic enzymes and apoptotic factors were not altered in treated ovaries compared to controls. In DEHP-treated testes, germ cell migration was impaired and germ cell death was significantly increased compared to controls. Overall, the results of this study suggest that neonatal exposure to DEHP in pigs leads to sex-specific disruption of the reproductive system.

Mono-n-Butyl Phthalate Distributes to the Mouse Ovary and Liver and Alters the Expression of Phthalate-Metabolizing Enzymes in Both Tissues.

Humans are exposed to phthalates daily via items such as personal care products and medications. Reproductive toxicity has been documented in mice exposed to di-n-butyl phthalate (DBP); however, quantitative evidence of its metabolite, mono-n-butyl phthalate (MBP), reaching the mouse ovary and its effects on hepatic and ovarian biotransformation enzymes in treated mice is still lacking. Liquid chromatography/tandem mass spectrometry (LC-MS/MS) was employed to quantify MBP levels in liver, serum, and ovary from mice treated with a single or repeated exposure to the parent compound, DBP. Adult CD-1 females were pipet fed once or for 10 days with vehicle (tocopherol-stripped corn oil) or DBP at 1, 10, and 1000 mg/kg/day. Tissues and serum were collected at 2, 6, 12, and 24 h after the single or final dose and subjected to LC-MS/MS. Ovaries and livers were processed for qPCR analysis of selected phthalate-associated biotransformation enzymes. Regardless of duration of exposure (single vs repeated), MBP was detected in the tissues of DBP-treated mice. In single dose mice, MBP levels peaked at ≤6 h and fell close to background levels by 24 h post-exposure. Following the last repeated dose, MBP levels peaked at ≤2 h and fell to background levels by 12 h. Hepatic and ovarian expression of Lpl, Aldh1a1, Adh1, Ugt1a6a, and Cyp1b1 were altered in DBP-treated mice in a time- and dose-specific manner. These findings confirm that MBP reaches the mouse liver and ovary after oral exposure to DBP and influences the expression of hepatic and ovarian phthalate-associated biotransformation enzymes.

The Effects of Tocotrienol on Bone Peptides in a Rat Model of Osteoporosis Induced by Metabolic Syndrome: The Possible Communication between Bone Cells.

A positive association between metabolic syndrome (MetS) and osteoporosis has been demonstrated in previous animal studies. The mechanisms of MetS in orchestrating the bone remodelling process have traditionally focused on the interactions between mature osteoblasts and osteoclasts, while the role of osteocytes is unexplored. Our earlier studies demonstrated the bone-promoting effects of tocotrienol using a rat model of osteoporosis induced by MetS. This study aimed to investigate the expression of osteocyte-derived peptides in the bone of rats with MetS-induced osteoporosis treated with tocotrienol. Age-matched male Wistar rats (12-week-old; n = 42) were divided into seven experimental groups. Two groups served as the baseline and normal group, respectively. The other five groups were fed with a high-carbohydrate high-fat (HCHF) diet to induce MetS. The five groups of HCHF animals were treated with tocopherol-stripped corn oil (vehicle), annatto tocotrienol (60 and 100 mg/kg), and palm tocotrienol (60 and 100 mg/kg) starting from week 8. At the end of the study, the rats were sacrificed and their right tibias were harvested. Protein was extracted from the metaphyseal region of the proximal right tibia and levels of bone peptides, including osteoprotegerin (OPG), soluble receptor activator of nuclear factor-kappa B ligand (sRANKL), sclerostin (SOST), Dickkopf-related protein 1 (DKK-1), fibroblast growth factor-23 (FGF-23), and parathyroid hormone (PTH), were measured. The vehicle-treated animals displayed higher levels of sRANKL, SOST, DKK-1, FGF-23, and PTH as compared to the normal animals. Oral supplementation of annatto and palm tocotrienol (60 and 100 mg/kg) reduced the levels of sRANKL and FGF-23 in the HCHF animals. Only 100 mg/kg annatto and palm tocotrienol lowered SOST and DKK-1 levels in the HCHF animals. In conclusion, tocotrienol exerts potential skeletal-promoting benefit by modulating the levels of osteocytes-derived bone-related peptides.

Environmentally relevant exposure to dibutyl phthalate disrupts DNA damage repair gene expression in the mouse ovary†.

Phthalates have a history of reproductive toxicity in animal models and associations with adverse reproductive outcomes in women. Human exposure to dibutyl phthalate (DBP) occurs via consumer products (7-10μg/kg/day) and medications (1-233μg/kg/day). Most DBP toxicity studies have focused on high supraphysiological exposure levels; thus, very little is known about exposures occurring at environmentally relevant levels. CD-1 female mice (80days old) were treated with tocopherol-stripped corn oil (vehicle control) or DBP dissolved in oil at environmentally relevant (10 and 100μg/kg/day) or higher (1000μg/kg/day) levels for 30days to evaluate effects on DNA damage response (DDR) pathway genes and folliculogenesis. DBP exposure caused dose-dependent effects on folliculogenesis and gene expression. Specifically, animals exposed to the high dose of DBP had more atretic follicles in their ovaries, while in those treated with environmentally relevant doses, follicle numbers were no different from vehicle-treated controls. DBP exposure significantly reduced the expression of DDR genes including those involved in homologous recombination (Atm, Brca1, Mre11a, Rad50), mismatch repair (Msh3, Msh6), and nucleotide excision repair (Xpc, Pcna) in a dose-specific manner. Interestingly, staining for the DNA damage marker, γH2AX, was similar between treatments. DBP exposure did not result in differential DNA methylation in the Brca1 promoter but significantly reduced transcript levels for the maintenance DNA methyltransferase, Dnmt1, in the ovary. Collectively, these findings show that oral exposure to environmentally relevant levels of DBP for 30days does not significantly impact folliculogenesis in adult mice but leads to aberrant ovarian expression of DDR genes.

Exposure to di-(2-ethylhexyl) phthalate transgenerationally alters anxiety-like behavior and amygdala gene expression in adult male and female mice

Phthalates are industrial plasticizers and stabilizers commonly found in polyvinyl chloride plastic and consumer products, including food packaging, cosmetics, medical devices, and children's toys. Di-(2-ethylhexyl) phthalate (DEHP), one of the most commonly used phthalates, exhibits endocrine-disrupting characteristics and direct exposure leads to reproductive deficits and abnormalities in anxiety-related behaviors. Importantly, increasing evidence indicates that the impacts of DEHP exposure on reproduction and social behavior persist across multiple generations. In this study, we tested the hypothesis that transgenerational DEHP exposure alters anxiety-like behavior and neural gene expression in both male and female mice. Pregnant CD-1 mice were orally dosed daily with either tocopherol-stripped corn oil or DEHP (20 or 200 μg/kg/day; 500 or 750 mg/kg/day) from gestational day 10.5 until birth to produce the F1 generation. Females from each generation were bred with untreated, unrelated CD-1 males to produce subsequent generations. Behavior and gene expression assays were performed with adult, intact F3 males and females. Transgenerational DEHP exposure increased time spent in the open arm in the elevated plus maze for adult females (750 mg/kg/day lineage), but not males. In adult females, we observed a down-regulation of mRNA expression of estrogen receptor 1 in the 200 μg/kg/day and 500 mg/kg/day treatment lineages, mineralocorticoid receptor in the 200 μg/kg/day lineage, and dopamine receptor 2 in the 20 μg/kg/day and 750 mg/kg/day lineages. In adult males, we found an up-regulation of estrogen receptor 2 in the 20 and 200 μg/kg/day lineages, and dopamine receptor 1 in the 20 μg/kg/day and 750 mg/kg/day lineages. No hippocampal gene expression modifications were observed in response to treatment. These results implicate dose-specific transgenerational effects on behavior and neural gene expression in adult male and female mice.

Gamma-tocopherol ameliorates hyperglycemia-induced hepatic inflammation associated with NLRP3 inflammasome in alloxan-induced diabetic mice.

BACKGROUND/OBJECTIVESHyperglycemia-induced hepatic damage has been recognized as one of the major cause of complications in diabetes. Hepatic complications are associated with inflammation and oxidative stress in diabetes. In this study, we investigated the hypothesis that gamma-tocopherol (GT) supplementation ameliorates NLRP3 inflammasome associated hepatic inflammation in diabetes.MATERIALS/METHODSDiabetes was induced by the intraperitoneal injection of alloxan (150 mg/kg. BW) in ICR mice. All mice were fed with a control diet (AIN-76A). After diabetes was induced (fasting glucose level ≥ 250 mg/dL), the mice were treated with tocopherol-stripped corn oil or GT-supplemented (35 mg/kg) corn oil, respectively, by gavage for 2 weeks.RESULTSGT supplementation reduced fasting blood glucose levels in diabetic mice relative to non-treated diabetic mice. Moreover, GT supplementation ameliorated hyperglycemia-induced hepatic damage by regulation of NOD-like receptor protein 3 (NLRP3)-inflammasome associated inflammation represented by NLRP3, apoptosis-associated speck-like protein containing a caspase-recruitment domain, caspase-1, nuclear factor-κB pathway as well as oxidative stress demonstrated by nuclear factor erythroid 2-related factor 2, NAD(P)H dehydrogenase quinone 1, catalase and glutathione-dependent peroxidase in diabetic mice.CONCLUSIONThe findings suggested that GT supplementation ameliorated hepatic damage by attenuating inflammation and oxidative stress in alloxan-induced diabetic mice. Taken together, GT could be a beneficial nutrient that can ameliorate inflammatory responses associated with NLRP3 inflammasome in hyperglycemia-induced hepatic damage.

Metabolomic profiling of serum in aging mice supplemented with tocotrienol-rich fraction for identification of female reproductive aging biomarkers

Ovarian aging has been associated with increased oxidative stress leading to loss of ovarian function and infertility. Tocotrienol, a potent antioxidant, has been proven to exert beneficial effects in the female reproductive system. Serum metabolites were analyzed to examine the biochemical changes and to identify biomarkers related to reproductive aging that could lead to poor embryo quality and development. Female Mus musculus mice were divided into four groups. Six-month-old mice were given tocopherol-stripped corn oil as a vehicle control while other groups were supplemented orally with tocotrienol-rich fraction (TRF) at doses of 90, 120, and 150 mg/kg bodyweight for two months, respectively. After two months, mice from all groups were super ovulated, and euthanized. Embryos were collected at the 2-cell stage and cultured to monitor their development while serum was used for metabolomic analysis. The percentage of normal embryos and development of embryos to blastocyst stage were significantly higher in groups supplemented with TRF. A total of 71 metabolites that are related to reproductive aging were identified in all groups and significant changes were detected in metabolic pathways that include fatty acids, amino acids metabolism and steroid hormone biosynthesis. These changes suggest that aging has a negative impact on cellular energy storage, energy metabolism and oxidative stress that subsequently affect female fertility. Supplementation with TRF prevented the impact of age related metabolic changes on the embryo. Thus, it appears that TRF exerts a protective mechanism towards female reproductive aging.

Tocotrienol-rich fraction supplementation prevents foetal loss in females mated with corticosterone-treated male Sprague-Dawley rats

This study examined whether tocotrienol supplementation to corticosterone-treated male rats could prevent foetal loss in females upon their mating. Epididymides of adult male Sprague-Dawley (SD) rats with proven fertility were surgically separated at the testis-caput junction. Twenty-four hours post-surgery, these animals received for 7days either: tocopherol-stripped corn oil (Control), corticosterone 25mg/kg s.c. (CORT), CORT 25mg/kg s.c. and tocotrienol-rich fraction (TRF) 100mg/kg orally (CORT+TRF) or TRF 100mg/kg orally (TRF). On day 8, males were cohabited with proestrus females. A spermatozoa-positive vaginal smear indicated pregnancy. Males were euthanised for analysis of testosterone and antioxidant activities. Reproductive organs were weighed. On day 8 of pregnancy, females were laparotomised to count the number of implantation sites. Pregnancy was continued until term. Number of pups delivered and their weights were determined. Data were analysed using ANOVA. Malondialdehyde levels were significantly lower in CORT+TRF group compared with CORT group. Enzymatic antioxidant activities, testosterone level and reproductive organ weights were significantly higher in CORT+TRF group compared with CORT group. Number of implantation sites and live pups delivered, and their birth weights from females mated with CORT+TRF males were significantly higher compared to CORT group. Therefore, TRF prevents foetal loss in females mated with CORT+TRF-treated males.

The Effects of Vitamin E from Elaeis guineensis (Oil Palm) in a Rat Model of Bone Loss Due to Metabolic Syndrome.

The beneficial effects of vitamin E in improving components of MetS or bone loss have been established. This study aimed to investigate the potential of palm vitamin E (PVE) as a single agent, targeting MetS and bone loss concurrently, using a MetS animal model. Twelve-week-old male Wistar rats were divided into five groups. The baseline group was sacrificed upon arrival. The normal group was given standard rat chow. The remaining three groups were fed with high-carbohydrate high-fat (HCHF) diet and treated with tocopherol-stripped corn oil (vehicle), 60 mg/kg or 100 mg/kg PVE. At the end of the study, the rats were evaluated for MetS parameters and bone density. After euthanasia, blood and femurs were harvested for the evaluation of lipid profile, bone histomorphometric analysis, and remodeling markers. PVE improved blood pressure, glycemic status, and lipid profile; increased osteoblast surface, osteoid surface, bone volume, and trabecular thickness, as well as decreased eroded surface and single-labeled surface. Administration of PVE also significantly reduced leptin level in the HCHF rats. PVE is a potential agent in concurrently preventing MetS and protecting bone loss. This may be, in part, achieved by reducing the leptin level and modulating the bone remodeling activity in male rats.

Exploring the potential of tocotrienol from Bixa orellana as a single agent targeting metabolic syndrome and bone loss.

Metabolic syndrome (MetS) is associated with osteoporosis due to the underlying inflammatory and hormonal changes. Annatto tocotrienol has been shown to improve medical complications associated with MetS or bone loss in animal studies. This study aimed to investigate the effects of annatto tocotrienol as a single treatment for MetS and osteoporosis in high-carbohydrate high-fat (HCHF) diet-induced MetS animals. Three-month-old male Wistar rats were randomly divided into five groups. The baseline group was euthanized at the onset of the study. The normal group received standard rat chow and tap water. The remaining groups received HCHF diet and treated with three different regimens orally daily: (a) tocopherol-stripped corn oil (the vehicle of tocotrienol), (b) 60 mg/kg annatto tocotrienol, and (c) 100 mg/kg annatto tocotrienol. At the end of the study, measurements of MetS parameters, body compositions, and bone mineral density were performed in animals before sacrifice. Upon euthanasia, blood and femur of the rats were harvested for the evaluations of bone microstructure, biomechanical strength, remodelling activities, hormonal changes, and inflammatory response. Treatment with annatto tocotrienol improved all MetS parameters (except abdominal obesity), trabecular bone microstructure, bone strength, increased osteoclast number, normalized hormonal changes and inflammatory response in the HCHF animals. In conclusion, annatto tocotrienol is a potential agent for managing MetS and osteoporosis concurrently. The beneficial effects of annatto tocotrienol may be attributed to its ability to prevent the hormonal changes and pro-inflammatory state in animals with MetS.

Exposure to an Environmentally Relevant Phthalate Mixture Causes Transgenerational Effects on Female Reproduction in Mice.

Phthalates are used in consumer products and are known endocrine-disrupting chemicals. However, limited information is available on the effects of phthalate mixtures on female reproduction. Previously, we developed a phthalate mixture made of 35% diethyl phthalate, 21% di(2-ethylhexyl) phthalate, 15% dibutyl phthalate, 15% di-isononyl phthalate, 8% di-isobutyl phthalate, and 5% benzylbutyl phthalate that mimics human exposure. We tested the effects of prenatal exposure to this mixture on reproductive outcomes in first-filial-generation (F1) female mice and found that it impaired reproductive outcomes. However, the impact of this exposure on second-filial-generation (F2) and third-filial-generation (F3) females was unknown. Thus, we hypothesized that prenatal exposure to the phthalate mixture induces multigenerational and transgenerational effects on female reproduction. Pregnant CD-1 dams were orally dosed with vehicle (tocopherol-stripped corn oil) or a phthalate mixture (20 and 200 µg/kg/d, 200 and 500 mg/kg/d) daily from gestational day 10 to birth. Adult F1 females born to these dams were used to generate the F2 generation and adult F2 females born to F1 females were used to generate the F3 generation. F2 and F3 females were subjected to tissue collections and fertility tests. Prenatal phthalate mixture exposure increased uterine weight, anogenital distance, and body weight; induced cystic ovaries; and caused fertility complications in the F2 generation. It also increased uterine weight, decreased anogenital distance, and caused fertility complications in the F3 generation. These data suggest that prenatal exposure to the phthalate mixture induces multigenerational and transgenerational effects on female reproduction.

Prenatal exposure to an environmentally relevant phthalate mixture disrupts reproduction in F1 female mice

Phthalates are used in a large variety of products, such as building materials, medical devices, and personal care products. Most previous studies on the toxicity of phthalates have focused on single phthalates, but it is also important to study the effects of phthalate mixtures because humans are exposed to phthalate mixtures. Thus, we tested the hypothesis that prenatal exposure to an environmentally relevant phthalate mixture adversely affects female reproduction in mice. To test this hypothesis, pregnant CD-1 dams were orally dosed with vehicle (tocopherol-stripped corn oil) or a phthalate mixture (20 and 200μg/kg/day, 200 and 500mg/kg/day) daily from gestational day 10 to birth. The mixture was based on the composition of phthalates detected in urine samples from pregnant women in Illinois. The mixture included 35% diethyl phthalate, 21% di(2-ethylhexyl) phthalate, 15% dibutyl phthalate, 15% diisononyl phthalate, 8% diisobutyl phthalate, and 5% benzylbutyl phthalate. Female mice born to the exposed dams were subjected to tissue collections and fertility tests at different ages. Our results indicate that prenatal exposure to the phthalate mixture significantly increased uterine weight and decreased anogenital distance on postnatal days 8 and 60, induced cystic ovaries at 13months, disrupted estrous cyclicity, reduced fertility-related indices, and caused some breeding complications at 3, 6, and 9months of age. Collectively, our data suggest that prenatal exposure to an environmentally relevant phthalate mixture disrupts aspects of female reproduction in mice.

Prenatal exposure to DEHP induces premature reproductive senescence in male mice

Di-(2-ethylhexyl) phthalate (DEHP) is the most commonly used phthalate, and it is an endocrine-disrupting chemical. This study tested a hypothesis that prenatal exposure to DEHP lays the foundation for premature gonadal dysfunction and subsequent reproductive senescence in male mice. Pregnant female CD-1 mice were orally dosed with vehicle control (tocopherol-stripped corn oil) or with 20 μg/kg/day, 200 μg/kg/day, 500 mg/kg/day, or 750 mg/kg/day of DEHP from gestational day 11 to birth. Overall, the prenatal DEHP exposure did not cause any overt physical health problems in male offspring, as no significant differences in their body nor gonadal weight were seen up to the age of 23 months. However, an age- and dose-dependent gonadal dysfunction was observed. As early as 7 months of age, the 750 mg/kg/day group of mice exhibited significantly reduced fertility. At 19 months of age, 86% of the 750 mg/kg/day mice became infertile, whereas only 25% of the control mice were infertile. At this age, all of the DEHP-exposed mice had lower serum testosterone levels, higher serum estradiol levels, and higher LH levels compared with control mice. Histological evaluations showed that mice prenatally exposed to DEHP displayed a wide array of gonadal and epididymal abnormalities such as increased germ cell apoptosis, degenerative seminiferous tubules, oligozoospermia, asthenozoospermia, and teratozoospermia in comparison to age-matching control mice. In summary, this study shows that prenatal exposure to DEHP induces premature reproductive senescence in male mice.

Effects of oral exposure to the phthalate substitute acetyl tributyl citrate on female reproduction in mice.

Acetyl tributyl citrate (ATBC), is a phthalate substitute used in food and medical plastics, cosmetics and toys. Although systemically safe up to 1000 mg kg-1 day-1 , its ability to cause reproductive toxicity in females at levels below 50 mg kg-1 day-1 has not been examined. This study evaluated the effects of lower ATBC exposures on female reproduction using mice. Adult CD-1 females (n = 7-8 per treatment) were dosed orally with tocopherol-stripped corn oil (vehicle), 5 or 10 mg kg-1 day-1 ATBC daily for 15 days, and then bred with a proven breeder male. ATBC exposure did not alter body weights, estrous cyclicity, and gestational and litter parameters. Relative spleen weight was slightly increased in the 5 mg kg-1 day-1 group. ATBC at 10 mg kg-1 day-1 targeted ovarian follicles and decreased the number of primordial, primary and secondary follicles present in the ovary. These findings suggest that low levels of ATBC may be detrimental to ovarian function, thus, more information is needed to understand better the impact of ATBC on female reproduction. Copyright © 2016 John Wiley & Sons, Ltd.

Prenatal exposure to di-(2-ethylhexyl) phthalate (DEHP) affects reproductive outcomes in female mice.

This study tested the hypothesis that prenatal DEHP exposure affects female reproduction. To test this hypothesis, pregnant female CD-1 mice were orally dosed daily with tocopherol-stripped corn oil (vehicle control) or DEHP (20 μg/kg/day-750 mg/kg/day) from gestation day 11-birth. Pups were counted, weighed, and sexed at birth, ovaries were subjected to evaluations of follicle numbers on postnatal days (PNDs) 8 and 21, and fertility was evaluated at 3-9 months. The results indicate that prenatal DEHP exposure increased male-to-female ratio compared to controls. Prenatal DEHP exposure also increased preantral follicle numbers at PND 21 compared to controls. Further, 22.2% of the 20 μg/kg/day treated animals took longer than 5 days to get pregnant at 3 months and 28.6% of the 750 mg/kg/day treated animals lost some of their pups at 6 months. Thus, prenatal DEHP exposure alters F1 sex ratio, increases preantral follicle numbers, and causes some breeding abnormalities.

Abstract 3693: Methaneseleninic acid and γ-tocopherol combination inhibits prostate tumor growth in a xenograft model .

Abstract Prostate Cancer (PCa) is the second leading cause of cancer-related deaths in American males. Several in vitro and in vivo studies have suggested that vitamin E as well as selenium possesses potential in the management of PCa. However, results from the large-scale Selenium and Vitamin E Cancer Prevention Trial (SELECT) found that vitamin E (α-tocopheryl acetate; 400 mg) and/or selenium (L-selenomethionine; 200 μg) were ineffective in preventing PCa. Based on these seemingly contradictory outcomes, we believe that the dose and formulation of both these agents were sub-optimal in the SELECT trial, and may be critical in providing appropriate biological response in PCa. Thus, additional studies are needed to define the most appropriate formulations of vitamin E and selenium as well as the optimal dosages of these two agents. Following a careful analysis of literature, we evaluated the effect of methylseleninic acid (MSA in sterile water; oral gavage) and/or γ-tocopherol (γT in tocopherol-stripped corn oil; oral gavage), at a dose much lower than used in SELECT, against prostate tumors in an immunecompromised mouse model. Sixty Nu/J mice were implanted with 22Rν1 cells, tumors were allowed to grow to an average volume of 36 mm3, followed by treatment in 6 groups (10 animals each): 1) Control (vehicle alone); 2) MSA (41 μg/kg); 3) γT (20.8 mg/kg); 4) γT (41.7 mg/kg); 5) MSA (41 μg/kg) + γT (20.8 mg/kg); and 6) MSA (41 μg/kg) + γT (41.7 mg/kg). The mice were treated for 2 weeks (5 days per week) and followed for tumor growth. At the end of experiment, the mice were sacrificed and further studies were done. Our data demonstrated that the combination of γT (20.8 mg/kg) and MSA (41 μg/kg) resulted in a significant decrease in i) serum prostate specific antigen levels, ii) tumor volume and tumor wet weight, and iii) Ki-67 proliferation index. We found that this combination also resulted in i) an up-regulation of pro-apoptotic Bax coupled with a down-regulation of the pro-survival protein Bcl2, thereby resulting in an increased Bax/Bcl2 ratio, and ii) an increase in pro-apoptotic protein Bad. Further, γT and MSA combination modulated levels of apolipoprotein E, selenoprotein P and Nrf2 in a fashion that favors anti-proliferative responses in PCa. Interestingly, we found that the combination using a lower dose of γT was much more effective than the higher dose, in most of the parameters evaluated. In the most effective treatment group, the approximate daily human equivalent dose for γT was 72 mg/day (corresponding to 20.8 mg/kg in mouse) and for MSA is 142 μg/day (corresponding to 41 μg/kg in mouse), which is significantly lower than the doses used in SELECT. Overall, our study suggests that γT and MSA, at the lower dose regimen, could be useful in PCa management. However, further studies with additional formulations and doses in more relevant animal model(s) are needed to confirm our findings. Citation Format: Chandra K. Singh, Mary A. Ndiaye, Imtiaz A. Siddiqui, Minakshi Nihal, Thomas Havighurst, Weixiong Zhong, Hasan Mukhtar, Nihal Ahmad. Methaneseleninic acid and γ-tocopherol combination inhibits prostate tumor growth in a xenograft model . [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3693. doi:10.1158/1538-7445.AM2013-3693

γ-Tocotrienol and γ-Tocopherol Are Primarily Metabolized to Conjugated 2-(β-carboxyethyl)-6-Hydroxy-2,7,8-Trimethylchroman and Sulfated Long-Chain Carboxychromanols in Rats1–3

The metabolism of γ-tocotrienol (γ-TE) and γ-tocopherol (γ-T) was investigated in human A549 cells and in rats. Similar to γ-T, A549 cells metabolized γ-TE to sulfated 9′-, 11′-, and 13′-carboxychromanol and their unconjugated counterparts. After 72-h incubation with the cells, 90% of long-chain carboxychromanols in the culture media from γ-TE, but <45% from γ-T, were in the sulfated form. The formation of these metabolites was further investigated in rats gavaged by γ-TE at 10 or 50 mg/kg, γ-T at 10 mg/kg, or tocopherol-stripped corn oil in controls. Six hours after a single dosing, the supplemented rats had increased plasma concentrations of 13′-carboxychromanol and sulfated 9′-, 11′-, 13′-carboxychromanol, whereas none of these metabolites were detectable in the controls. Sulfated 11′-carboxychromanol was the most abundant long-chain metabolite in γ-TE–supplemented rats. Sulfatase/glucuronidase hydrolysis revealed for the first time that >88% 2-(β-carboxyethyl)-6-hydroxychroman (γ-CEHC), the terminal β-oxidation metabolite, was in the conjugated form in the plasma. In all groups, conjugated γ-CEHC accounted for >75% of total metabolites, whereas free CEHC was a minor metabolite. At 10 mg/kg, the plasma concentrations of total metabolites from γ-TE–supplemented rats were higher (P < 0.05) than those from γ-T–fed rats. These results demonstrate that in rats, conjugation such as sulfation occurs parallel to β-oxidation in the liver and is quantitatively important to vitamin E metabolism. Conjugated long-chain carboxychromanols may be novel excreted metabolites during supplementation. Our data also provide in vivo evidence that γ-TE is more extensively metabolized than γ-T.

Factors Affecting Lycopene Oxidation in Oil-in-Water Emulsions

Evidence that dietary lycopene decreases the risk for a number of health conditions has generated new opportunities for the addition of lycopene to functional foods. This work examined the potential of oil-in-water emulsions as a lycopene delivery system for foods. Oil-in-water emulsions containing lycopene were prepared using different kinds of surfactant (cationic, anionic, and nonionic) and oil types (corn oil, stripped corn oil, and hexadecane). The formation of fatty acid oxidation products and the degradation of lycopene and tocopherol were then monitored. Fatty acids and lycopene had greater stability in oil-in-water emulsions stabilized by cationic dodecyltrimethylammonium bromide (DTAB) or nonionic polyoxyethylene (23) lauryl ether than by anionic sodium dodecyl sulfate (SDS). Oxidative stability in the corn oil-in-water emulsions stabilized by SDS was in the following order: tocopherol<lycopene<fatty acids. When emulsions were prepared using different carrier oils, the lycopene stability was in the following order: nonstripped corn oil>hexadecane>tocopherol-stripped corn oil. Lycopene degradation rates were similar in emulsions with and without fatty acids, suggesting that lycopene loss was independent of the presence of fatty acids. These results suggest that the stability of lycopene in oil-in-water emulsions could be inhibited by altering the emulsion droplet interface and by the presence of tocopherols.