Role of JNK and ERK1/2 MAPK signaling pathway in testicular injury of rats induced by di-N-butyl-phthalate (DBP)

BACKGROUND: Di-N-butyl-phthalate (DBP) is an endocrine disrupting substance. We investigated the adverse effect of DBP on testis of male rat and reveal its potential mechanism of MAPK signaling pathway involved this effect in vivo and in vitro. Gonadal hormone, sperm quality, morphological change and the activation status of JNK, ERK1/2 and p38 was determined in vivo. Primary Sertoli cell was established and cultivated with JNK, ERK1/2 inhibitors, then determine the cell viability, apoptosis and the expression of p-JNK, p-ERK1/2. Data in this study were presented as mean ± SD and determined by one-way analysis of variance (ANOVA) followed by Bonferroni's test. Difference was considered statistically significant at P < 0.05. RESULTS: In vivo experiment, DBP impaired the normal structure of testicular tissue, reduced testosterone levels in blood serum, decreased sperm count and increased sperm abnormality, p-ERK1/2 and p-JNK in rat testicular tissue increased in a dose-dependent manner. In vitro studies, DBP could decrease the viability of Sertoli cells and increase p-ERK1/2 and p-JNK. Cell apoptosis in SP600125 + DBP group was significantly lower than in DBP group (P < 0.05). p-JNK was not significantly decreased in SP600125 + DBP group, while p-ERK1/2 was significantly decreased in U0126 + DBP group. CONCLUSIONS: These results suggest that DBP can lead to testicular damage and the activation of ERK1/2 and JNK pathways, the JNK signaling pathway may be primarily associated with its effect.

Hypospadias induced by maternal exposure to di-n-butyl phthalate and its mechanisms in male rat offspring / 中华男科学杂志

Objective@#To induce hypospadias in male rat offspring by maternal exposure to di-n-butyl phthalate (DBP) during late pregnancy and further investigate its mechanisms.@*METHODS@#We randomly divided 20 pregnant rats into a DBP exposure and a control group, the former treated intragastrically with DBP while the latter with soybean oil at 750 mg per kilogram of the body weight per day from gestation days (GD) 14 to 18. On postnatal day (PND) 1, we recorded the incidence rate of hypospadias and observed the histopathological changes in the genital tubercle of the hypospadiac rats. We also measured the level of serum testosterone (T) by radioimmunoassay and determined the mRNA and protein expressions of the androgen receptor (AR), sonic hedgehog (Shh), bone morphogenetic protein 4 (Bmp4) and fibroblast growth factor 8 (Fgf8) in the genital tubercle by real-time PCR and Western blot.@*RESULTS@#No hypospadiac male rats were found in the control group. The incidence rate of hypospadias in male offspring was 43.6% in the DBP-treatment group. Histological analysis confirmed hypospadiac malformation. The serum testosterone concentration was decreased in the hypospadiac male rats as compared with the controls (［0.49 ± 0.05］ vs ［1.12 ± 0.05］ ng/ml, P <0.05). The mRNA expressions of AR, Shh, Bmp4 and Fgf8 in the genital tubercle were significantly lower in the hypospadiac male rats than in the controls (AR: 0.50 ± 0.05 vs 1.00 ± 0.12, P <0.05; Shh: 0.65 ± 0.07 vs 1.00 ± 0.15, P <0.05; Bmp4: 0.42 ± 0.05 vs 1.00 ± 0.13, P <0.05; Fgf8: 0.46 ± 0.04 vs 1.00 ± 0.12, P <0.05), and so were their protein expressions (AR: 0.34 ± 0.05 vs 1.00 ± 0.09, P <0.05; Shh: 0.51 ± 0.07 vs 1.00 ± 0.12, P <0.05; Bmp4: 0.43 ± 0.05 vs 1.00 ± 0.11, P <0.05; Fgf8: 0.57 ± 0.04 vs 1.00 ± 0.13, P <0.05).@*CONCLUSIONS@#Maternal exposure to DBP during late pregnancy can induce hypospadias in the male rat offspring. DBP affects the development of the genital tubercle by reducing the serum T concentration and expressions of AR, Shh, Bmp4 and Fgf8 in the genital tubercle, which might underlie the mechanism of DBP inducing hypospadias.

Impact of intrauterine Dibutyl phthalate exposure to rat offsprings on reproductive and developmental toxicity / 上海预防医学

Objective ] To observe the effects of intrauterine DBP exposure on the reproductive system of both mother rats and mature F 1 generation rats . [ Methods ] The pregnant rats were administered DBP in various doses (20 mg/kg,100 mg/kg and 500 mg/kg) by gavage.Enzyme linked immunosorbent assay ( ELISA ) was applied to detect the hormone levels in serum , including estrogen two alcohol ( E2 ) , luteinizing hormone ( LH ) , follicle stimulating hormone ( FSH ) and testosterone ( T ) . [ Results] The results showed that the experimental doses of DBP exerted significant effect on serum hormone levels but no significant effects on various organs of mother rats .Compared with the control group , serum T levels in the groups treated with 100 mg/kg and 500 mg/kg were significantly decreased (P<0.05),while FSH level increased in 500 mg/kg dose group (P<0.05);with the increase of DBP exposure doses, the weight of mother rats during gestational period decreased significantly (P<0.05).For the F1 female rats, on PND7, the serum LH and T levels decreased with DBP exposure doses increased (P<0.05);on PND26, the E2 levels of the female pups decreased significantly (P<0.05),the FSH levels of rats in dosed group (100 and 500 mg/kg) were significantly lower than those in the control group (P<0.05),and T level in 500 mg/kg DBP dosed group increased (P<0.05) obviously. [Conclusion] Intrauterine DBP exposure exerts significant toxic effect on the reproductive system of F 1 rats; even low dose of DBP can lead to changes in the serum hormone levels , which can be illustrated by the various metabolic profiles.

Di-(n-butyl)-phthalate-induced oxidative stress and depression-like behavior in mice with or without ovalbumin immunization / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the relationship between atopic allergy and depression and the role of DBP in the development of depression.</p><p><b>METHODS</b>BALB/c mice were randomly divided into eight groups: saline; ovalbumin (OVA)-immunized; saline+DBP (0.45 mg/kg•d); saline+DBP (45 mg/kg•d); DBP (0.45 mg/kg•d) OVA-immunized; DBP (45 mg/kg•d) OVA-immunized; saline+hydrocortisone (30 mg/kg•d); and hydrocortisone (30 mg/kg•d)-exposed OVA-immunized. Behavior (e.g. open-field, tail suspension, and forced swimming tests), viscera coefficients (brain and spleen), oxidative damage [e.g. reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH)], as well as levels of IgE and IL-4, were then analyzed.</p><p><b>RESULTS</b>In the saline and OVA groups, the degree of depression symptoms in mice increased with increasing DBP concentration. Additionally, the OVA-immunity groups were associated with more serious depressive behavior compared with the same exposure concentration in the saline group. Oxidative damage was associated with a dose-dependent increase in DBP in the different groups. IL-4 and IgE levels were associated with low-dose DBP stimulation, which changed to high-dose inhibition with increasing DBP exposure, possibly due to spleen injury seen at high DBP concentrations.</p><p><b>CONCLUSION</b>Development of an atopic allergy has the potential to increase the risk of depression in mice, and it seems that DBP helps OVA to exert its effect in our present model. Moreover, the results of our study implicate a certain connection between brain oxidative stress and depression, which deserves a further exploration.</p>

Combined Toxic Effects of DBP and DEHP on Spermatogenesis in Male Rats / 环境与健康杂志

0.05).DBP and DEHP obviously induced a decrease in organ body weight ratios of testis and epididymis and an increase in organ body weights ratios of liver.Obvious decrease in the sperm counts,spermatozoon survival rate and significant increase in the rate of the sperm deformation were observed.There was synergism between DBP and DEHP on the testis,epididymis and liver organ body weight ratio,as well as sperm counts,sperm survival and deformation rates.Pathological examination showed the seminiferous tubules were irregular shape,degenerative atrophy and interstitial substance broadening,and the seminiferous epithelium were degeneration.Epididymis epithelium was damaged and few of mature sperm was seen.Conclusion DBP combined with DEHP can cause obvious toxic effects on reproductive function in male rats.DBP and DEHP mixture can strongly affect the sperm quantity and quality.Also,some toxic effects to epididymis are observed.

Suppression Effect of Di-n-butyl Phthalate in vitro on Superoxide Dismutase of Various Organs of Mice / 医学研究杂志

Objective The present study was conducted to study the oxidation damage effects of DBP on organs of mice and the molecular mechanisms of the effects. Methods The cells of the organs (liver,kidney,testis,lung) were exposed to different concentration of DBP (0?mol/L,5?mol/L,20?mol/L,80?mol/L) for one hour in vitro,and then the superoxide dismutase (SOD) activities of those cells of different organs were measured. Results With statistical significance,the SOD activities in liver,kidney,testis,lung cells were increased gradually with the increase of DBP concentrations. Conclusion The results suggested that DBP could induce the oxidative damage in liver,lung,kidney and testis cells of mice.

Combined Toxic Effects of Di-n-butyl Phthalate and Di-2-ethylhexyl Phthalate on Fertility in Male Rats / 环境与健康杂志

Objective To study the combined toxic effects of di-n-butyl phthalate(DBP)and di-2-ethylhexyl phthalate(DEHP)on sex hormone and lipid peroxidation in male rats.Methods According to 2?2 factorial analysis,thirty-two healthy and clean adult male SD rats were randomly divided into 4 groups,including a control group(given coin oil) and three experimental groups:DBP(1/20 LD50,1.0 g/kg,dissolved in coin oil),DEHP(1/20 LD50,1.7 g/kg,dissolved in coin oil) and DBP+DEHP(1.0 g/kg + 1.7 g/kg,dissolved in coin oil),8 rats in each group,through gavage,once a day,for 8 consecutive weeks.The spectrophotometric method was used to measure the activity of lipid peroxidation SOD,GSH and GSH-Px level in testis homogenate.The activities of ACP,AKP and ?-GT were assessed in testis homogenate.Radioimmunoassay was used to determine the testosterone,LH and FSH levels in the serum.Results There was synergism between DBP and DEHP on the SOD activity in testicle and testosterone level in serum,and there was antagonism between DBP and DEHP on the ?-GT and ACP activity in testicle,as well as the FSH level in serum.Conclusion DBP combined with DEHP can cause obvious toxic effects on reproductive function in male rats.The change of testosterone biosynthetic enzymes and the levels of T in serum and disordered physiologic balances of hypothalamic-pituitarytestis axis may be key factors contributing to the decrease of testosterone,then the decrease of reproductive function in male rats.

Effect of Dibutyl Phthalate on Development of Filial Generation Drosophila Melanogaster / 环境与健康杂志

Objective To study the effect of di-n-butyl phthalate (DBP) on the development of Oregon K Drosophila melanogaster. Methods Drosophila melanogasters were divided randomly into four groups and were continuously fed with the medium containing 0, 0.2%, 0.6%, 1.8% DBP respectively during entire trial period. The growth and the development of filial generation drosophilas were observed. Results Compared with the control, the eclosion periods of filial generation drosophilas in DBP groups were significant longer(P

Studies of Di-n-butyl Phthalate-OP Emulsion in the Treatment of Demodicidosis / 中国寄生虫学与寄生虫病杂志

Objective To observe the curative effect of Di\|n\|butyl phthalate\|OP emulsion in the treatment of demodicidosis. \ Methods\ 447 cases with Demodex infection on face were treated with Di\|n\|butyl phthalate\|OP emulsion. Among them, 30 cases suffering from acne, tetter and pustule were also randomly observed. 20 days after treatment negative conversion rate and the therapeutic effect were evaluated. At the same time, the effect of this solution was compared with that of other three medicaments (FuManLing, 2% metronidazole and 8% metronidazole preparations). In vitro test of mites\|killing, toxicity test in experimental animals and the safety evaluation for local application were also performed. \ Results \ Results showed that the negative conversion rate was 92^8%(415/447), effective rate for the cases showing evident face damage was 90^0%(27/30). The result also indicated that the OP emulsion medicament was more effective than other three medicaments (P