Maternal exposure to Di-n-butyl phthalate (DBP) aggravate gestational diabetes mellitus via FoxM1 suppression by pSTAT1 signalling.

The study focused on the toxicological effect of Di-n-butyl phthalate (DBP) on the expression of Phosphorylated signal transducer and activator of transcription 1 (pSTAT1) -regulated Forkhead box protein M1 (FoxM1), which might provide a new understanding of gestational diabetes mellitus (GDM) development and a potential target for treatment. Streptozotocin (STZ) (40 mg/kg) was introduced in maternal rats by intraperitoneal injection on gestation day 0 (GD 0) in the STZ and STZ + DBP groups. DBP was introduced in maternal rats by oral feeding in the STZ + DBP group over the following 3 days (750 mg/kg/day). The changes in fasting blood glucose level in rats were detected on GD 1 and GD 5. The insulin levels in maternal rats and PIBCs were measured on GD 18. The Oral Glucose Tolerance Test (OGTT) test was performed on GD 18 to check the stability of the GDM model. The primary islet ß cells (PIBCs) were established for in vitro experiments. We examined the FoxM1 and pSTAT1 expression in pancreas by immunohistochemistry. Real-time PCR and Western blot were used to detect the pSTAR1 and FoxM1 protein and mRNA gene expression levels in PIBCs. Cell Counting Kit-8 (CCK-8) and flow cytometric analysis was used to test the viability and apoptosis of cells. The results showed that the STZ + DBP group had higher glucose and lower insulin secretion levels than the other groups by both fasting test and OGTT. FoxM1 was significantly suppressed while pSTAT1 was highly expressed after DBP exposure. FoxM1 could be regulated by pSTAT1. DBP can influence the progression of GDM through its toxicological effect, which significantly increases the expression of pSTAT1 and suppresses FoxM1, causing a decline in ß cell viability.

Di-n-butyl phthalate (DBP) reduces epithelial-mesenchymal transition via IP3R in hypospadias during maternal exposure.

OBJECTIVE: This study focused on the oxidative stress effect of di-n-butyl phthalate (DBP) on development of the urinary system. METHODS: We examined the mRNA expression of genital tubercle (GT) in control and DBP induced hypospadias group by Affymetrix Rat 230 2.0 Array. Real-time PCR and Western Blot were used to detect the protein and mRNA expression levels of inositol-1,4,5-triphate-receptor (IP3R) and epithelial-mesenchymal-transition (EMT)-related molecular markers, such as E-cadherin, ß-Catenin, Snail, N-cadherin, in the GT of hypospadiac male rats and controls. The results of array were further confirmed in vitro. The changes of intracellular calcium concentration in urethral epithelial cells were detected by Fluo-3-AM before and after DBP treatment. The levels of reactive oxygen species (ROS) in urethral epithelial cells were measured by DCFH-DA with different concentrations of DBP (0, 1, 10, 100 µmol/L) treatment. RESULTS: The mRNA expression profiles of GT in control and DBP induced hypospadias group showed high expression of IP3R and the abnormalities of EMT. Compared to the control group, the expression levels of IP3R, E-cadherin and ß-Catenin increased at both the protein and mRNA levels. However the expression levels of Snail and N-cadherin decreased. The intracellular calcium concentration increased significantly after DBP treatment. The effect of DBP on urethral epithelial cells was linked to the generation of oxidative stress. CONCLUSION: DBP can influence the development of GT through its oxidative stress effect, which significantly increases the concentration of calcium and inhibits EMT in urethral epithelial cells, and block the fusion process of urethral groove, causing the occurrence of hypospadias. This study provides a new understanding of DBP's molecular mechanisms on hypospadias and may lead to new treatment strategies for the disease.

Maternal exposure to di-n-butyl phthalate (DBP) promotes epithelial-mesenchymal transition via regulation of autophagy in uroepithelial cell.

Maternal exposure to di-n-butyl phthalate (DBP) induces hypospadias, but the underlying mechanisms remain elusive. Here we hypothesize that aberrant activation of autophagy and epithelial-mesenchymal transition (EMT) are the leading cause of DBP-related hypospadias. Pregnant rats received DBP orally at a dose of 750 mg/kg/day during gestational days 14-18. In DBP-induced hypospadiac male offspring, immunohistochemistry (IHC) staining and Western blot showed increased expression of autophagy and EMT markers in genital tubercle (GT) tissue compared to the control. In addition, lower testosterone levels and androgen receptor (AR) expression in GT tissue were detected. In vitro studies revealed that impaired AR signaling was involved in DBP-induced autophagy and autophagy activation furthermore promoted EMT in urethral epithelial cells. DBP combined with chloroquine, an autophagy inhibitor, reduced the expression of EMT markers compared with DBP treatment alone, while DBP combined with the autophagy inducer rapamycin elevated the expression of EMT markers. The autophagy-lysosomal pathway inhibitor CQ but not proteasome inhibitor MG-132 rescued the decrease of E-cadherin after DBP treatment, which indicated autophagy-induced E-cadherin degradation contributes to DBP-related EMT. Taken together, our findings show that prenatal exposure to DBP induces abnormal autophagy and EMT that may play important roles in hypospadias development.

Potential involvement of Fgf10/Fgfr2 and androgen receptor (AR) in renal fibrosis in adult male rat offspring subjected to prenatal exposure to di-n-butyl phthalate (DBP).

BACKGROUND: We previously demonstrated that maternal exposure to di-n-butyl phthalate (DBP) induces dysplasia of the kidney in newborn male offspring and renal fibrosis in adults. But the underlying mechanisms remain elusive. Fgf10/Fgfr2 and androgen receptor (AR) are known to be important for renal development. We therefore investigated whether these genes are involved in DBP-induced renal fibrosis. MATERIALS AND METHODS: Using Sprague-Dawley rats and rat renal proximal tubular cells (NRK52E), we determined the potential involvement of Fgf10, Fgfr2 and AR in DBP-induced renal fibrosis. RESULTS: We found that maternal exposure to DBP induces renal fibrosis in adult male offspring. A lower serum testosterone concentration and reduced expression of Fgf10, Fgfr2 and AR were detected in these animals. These was a trend toward lower expression of Fgf10, Fgfr2 and AR in NRK52E cells subjected to DBP exposure. Furthermore, higher expression levels of TGF-ß and α-SMA were observed in abnormal renal tissue and DBP-treated NRK52E cells. CONCLUSION: Our findings suggest the potential involvement of Fgf10/Fgfr2 and AR in renal fibrosis of adult male rat offspring induced by prenatal exposure to DBP. The anti-androgenic effects of DBP might play an important role in this pathological process.

Maternal exposure to di-n-butyl phthalate (DBP) induces renal fibrosis in adult rat offspring.

This study was to determine the impact of maternal exposure to di-n-butyl phthalate (DBP) on renal development and fibrosis in adult offspring. Pregnant rats received DBP at a dose of 850 mg/kg BW/day by oral perfusion during gestational days 14-18. In DBP exposed newborn offspring, gross observation and histopathological examination revealed the dysplasia of kidney. The expression of genes related to renal development was also changed. In DBP exposed adult offspring, histopathological examination and Masson's trichrome staining revealed the pathological changes of renal fibrosis. Furthermore, higher expression levels of transforming growth factor- ß (TGF-ß) and alpha-smooth muscle actin (α-SMA) were also detected. In vitro studies reveal that DBP promoted the activation of NRK49F cells and G2/M arrest in NRK52E cells at a sublethal dose. The effect of DBP on these cell lines was linked to the generation of oxidative stress. In addition, DBP induced oxidative stress in both renal fibroblasts and tubular epithelial cells, whereas vitamin C ameliorated the changes caused by DBP. In conclusion, our results showed that prenatal exposure to DBP may generate oxidative stress in both renal fibroblasts and tubular epithelial cells, leading to kidney dysplasia and renal fibrosis.

Maternal exposure to di-n-butyl phthalate (DBP) induces combined anorectal and urogenital malformations in male rat offspring.

Anorectal malformations in combination with hypospadias (ARMs & hypospadias) are a type of complex congenital malformations. The underlying mechanisms of this deformity are largely unknown. In this study, we comprehensively characterized the dysplasia, histological malformations, and genetic changes of ARMs & hypospadias in male rats after maternal exposure to di-n-butyl phthalate (DBP) by gastric intubation at doses of 850mg/kg bw/day during GD11-15. On postnatal day 1, anatomical and histopathological analysis confirmed combined malformations of the genital tubercle (GT), terminal rectum (TR) and testes. DBP-induced dysplasia was also seen in the kidney, lung, spleen, heart and liver of ARMs & hypospadias male rats. Moreover, decreased levels of serum testosterone, as well as reduced expression of genes related to the androgen signaling pathway (Cyp11a1, Hsd3b, Scarb1, Star, AR, Srd5a2) were found in the testes of ARMs & hypospadias male rats after DBP exposure as compared to untreated controls. Further, decreased mRNA levels of Shh, Fgf10, Gli2, Gli3, Bmp4, Wnt5a, Hoxa13, Hoxd13, Fgfr2 and AR were observed in TR and GT in the ARMs & hypospadias group. These results provide evidence that prenatal exposure to DBP can lead to combined anorectal and urogenital malformations as well as dysplasia of the testes.

Comparison of the clinical efficacy and safety of retroperitoneal laparoscopic ureterolithotomy and ureteroscopic holmium laser lithotripsy in the treatment of obstructive upper ureteral calculi with concurrent urinary tract infections.

The aim of this study is to compare the clinical efficacy and safety of retroperitoneal laparoscopic ureterolithotomy (RPLU) and ureteroscopic holmium laser lithotripsy (UHLL) as two minimally invasive procedures in managing obstructive upper ureteral calculi with concurrent urinary tract infections (UTI). The retrospective study included 189 patients who underwent unilateral obstructive upper ureteral stones with concurrent UTI from January 2007 to November 2014 at our institution. Patients received RPLU (81 cases) or UHLL (108 cases). All patients received preoperative anti-infection treatment (indwelling ureteral stent and/or preoperative antibiotics). Collected data, including sex, age, stone size, success rate, operation duration, post-operation hospitalization time, and post-operation complications, were compared. All patients were followed up for more than 6 months after surgeries, and no ureterostenosis occurred. The study included 189 patients, 41 (21.7 %) females and 148 (78.3 %) males with a medium age of 52 years (range 22-81 years). All surgeries were successfully performed without conversion to open surgery. Stone size in the RPLU group was larger than that of the UHLL group (16.1 ± 1.4 vs. 10.4 ± 1.6 mm, P = 0.012). Operative duration (P = 0.009) and hospitalization time (P < 0.001) in the UHLL group were significantly shorter than those in the RPLU group, whereas stone clearance rate was significantly higher in the RPLU group (100 vs. 88.9 %, P = 0.002). Of note, postoperative fever was more common in patients treated with UHLL (15 cases) versus RPLU (4 cases) (13.9 vs. 4.9 %, P = 0.043). Moreover, in the UHLL group, three patients without a preoperative indwelling ureteral stent were complicated with sepsis, which was not seen in RPLU group. In our study, the safety and stone clearance rate of RPLU are better than those of UHLL in the treatment of unilateral upper ureteric calculi with concurrent UTI. Preoperative antibiotics and indwelling ureteral stent may reduce the risk of postoperative infections.

Prenatal exposure to di-n-butyl phthalate (DBP) differentially alters androgen cascade in undeformed versus hypospadiac male rat offspring.

This study was to compare the alterations of androgen cascades in di-n-butyl phthalate (DBP)-exposed male offspring without hypospadias (undeformed) versus those with hypospadias. To induce hypospadias in male offspring, pregnant rats received DBP via oral gavage at a dose of 750mg/kg BW/day during gestational days 14-18. The mRNA expression levels of genes downstream of the androgen signaling pathway, such as androgen receptor (AR) and Srd5a2, in testes of undeformed rat pups were similar to those in controls; in hypospadiac rat pups these levels were significantly lower than those of control pups. In contrast, both undeformed and hypospadiac rats had decreased serum testosterone levels, reduced mRNA expression of key enzymes in the androgen synthetic pathway in the testes, and ablated genes of developmental pathways, such as Shh, Bmp4, Fgf8, Fgf10 and Fgfr2, in the genital tubercle (GT) as compared to those in DBP-unexposed controls, albeit hypospadiac rats had a more severe decrement than those of undeformed rats. Although other possibilities cannot be excluded, our findings suggest that the relatively normal levels of testosterone-AR-Srd5a2 may contribute to the resistance to DBP toxicity in undeformed rats. In conclusion, our results showed a potential correlation between decreased testosterone levels, reduced mRNA expression of AR and Srd5a2 and the occurrence of hypospadias in male rat offspring prenatally exposed to DBP.

Genetic research and structural dysplasia assessment of anorectal malformations in neonatal male rats induced by di(n-butyl) phthalate.

This study was the first to investigate the genetic abnormalities and structural dysplasia of anorectal malformations (ARMs) in male rats induced by di(n-butyl) phthalate (DBP). DBP was administered to timed-pregnant rats to establish the ARM rat model. The incidence of ARMs in male offspring was 39.5%. In neonatal period, decreased body weight and anogenital distance were observed. The general image and histological analysis of male offspring confirmed the presence of ARMs. Anatomical examination of the ARM male rats revealed the dysplasia in solid organs (heart-lung, liver, spleen, and kidney). The decreases of serum testosterone concentration and androgen receptor expression in terminal rectum were indicative of the antiandrogenic effects of DBP. Moreover, significant decreased mRNA expressions of these androgen-related genes such as sonic hedgehog, Gli2, Gli3, bone morphogenetic protein 4, Wnt5a, Hoxa13, Hoxd13, fibroblast growth factor 10, and fibroblast growth factor receptor 2 were found in terminal rectum of the ARM male pubs. These results demonstrated that development of ARM rats was impaired by maternal exposure to DBP. The antiandrogenic effects of DBP disturbing the androgen-related signaling networks might play an important role in the occurrence of ARMs.

Reduced Fgf10/Fgfr2 and androgen receptor (AR) in anorectal malformations male rats induced by di-n-butyl phthalate (DBP): A study on the local and systemic toxicology of DBP.

Previous study have demonstrated that not only the anorectal development but also the general conditions of anorectal malformations (ARMs) male rats are severely affected by di-n-butyl phthalate (DBP) maternal exposure. However, the mechanisms underlying DBP-induced congenital defects remain elusive. Reportedly, Fgf10/Fgfr2 and androgen receptor (AR) are pivotal for the development of multiple organs. In this study, we therefore investigated the expression of Fgf10/Fgfr2 together with AR in the terminal rectum and multiple organs of ARM male rats induced by in utero exposure to DBP. DBP was administered to pregnant rats to establish the model and the incidence of ARMs in male offspring was 39.5%. On postnatal day(PND)1, the gross photograph and histopathological staining confirmed the abnormal manifestations in these organs of newborn ARMs. Decreased anogenital distance, body weight and serum testosterone level were observed in ARM male offspring. The reduced expression of Fgf10/Fgfr2 mRNA and protein was seen in terminal rectum and kidney, spleen, liver, heart in ARM male rats, whereas the reduced expression of AR was only observed in the kidney and terminal rectum. Our findings suggest the potential involvement of altered Fgf10/Fgfr2 signaling and AR in pathogenesis of local and systemic development defects in ARMs male rats induce by DBP.

Expression of Wnt5a during development of anorectal malformations in a rat model of prenatal exposure to di(n-butyl) phthalate.

Mounting evidence has indicated the crucial role of Wnt5a in the embryonic development including guts. However, the Wnt5a involvement in the process of anorectal malformations (ARMs) remains unclear. In this study, we examined the expression of Wnt5a during ARMs development in the offspring of di(n-butyl) phthalate (DBP)-treated pregnant rats. During the neonatal period, Wnt5a expression was evaluated in the terminal rectum of ARM offspring, non-ARM littermates and controls. Using real-time polymerase chain reaction (real-time PCR), western-blot analysis and immunohistochemistry approaches, we found a significant decrease of Wnt5a expression in DBP-induced ARMs rats. Collectively, our results demonstrate the aberrant expression of Wnt5a during anorectal development, which suggests that Wnt5a might be involved in DBP-induced ARMs.

The role of androgen-induced growth factor (FGF8) on genital tubercle development in a hypospadiac male rat model of prenatal exposure to di-n-butyl phthalate.

Fibroblast growth factor 8 (FGF8) is an androgen-induced growth factor (AIGF) that is crucial for embryonic development. This study was developed to investigate the role of FGF8 in developmental abnormalities of the genital tubercle (GT) in hypospadiac male rats when prenatally exposed to di-n-butyl phthalate (DBP). DBP was administered to timed-pregnant rats to establish the hypospadiac rat model where the incidence of hypospadias in male offspring was 43.6%. On postnatal day (PND) 7, decreased mRNA and protein expression levels for androgen receptor (AR) and FGF8 were observed in the GT of hypospadiac rats. Decreased serum testosterone (T) levels were observed in groups displaying hypospadias, which was confirmed using histological analysis. Further anatomical examination using digital photography helped to reveal visualized expression of dysplasia in organs strongly associated with hypospadias. In addition, changes in body weight (BW) and anogenital distance (AGD) were recorded, showing definitive decreases. Collectively, these data clearly demonstrate an interaction between androgen and FGF8, which might play an important role in the occurrence of hypospadias and abnormal organ development induced by DBP.

Prenatal exposure to di-n-butyl phthalate induces anorectal malformations in male rat offspring.

The objectives of this study were to investigate the dysplasia, histological malformations, and genetic abnormalities in male rats induced by maternal exposure to di-n-butyl phthalate (DBP). Here we report novel findings concerning developmental abnormalities resulting from prenatal exposure to DBP, which leads to significant anorectal malformations (ARMs) in male rat offspring. The incidence of ARMs was 39.5% in male offspring and all abnormal pups were complicated with secondary megacolon. General images, histological analysis and anatomy examination confirmed the malformation. The development abnormalities such as decreased bodyweight (BW) and anogenital distance (AGD), shortened body lengths (with tail removed), as well as increased abdominal circumference were observed at different developmental stages of ARMs in male rat. The developmental abnormalities in both solid organs (brain, heart, liver, spleen, lung and kidney) and reproductive organs (testes and epididymis) of abnormal pubs on PND35 were also investigated. In addition, the serum testosterone (T) level of ARMs in male rats on PND1 was significantly lower than that of controls with accompanying reduced expression of androgen receptor (AR), sonic hedgehog (Shh) and bone morphogenetic protein 4 (Bmp4) mRNA from tissues of the terminal rectum. These results conclusively demonstrate for the first time that in utero exposure to DBP leads to an increased likelihood for the development of ARMs and subsequent complicating megacolon in male rat offspring.

11 beta-hydroxysteroid dehydrogenase type 1 promotes differentiation of 3T3-L1 preadipocyte.

AIM: To investigate the relationship between 11 beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), a potential link between obesity and type 2 diabetes, and preadipocyte differentiation. METHODS: Mouse 11beta-HSD1 siRNA plasmids were transfected into 3T3-L1 preadipocytes (a cell line derived from mouse Swiss3T3 cells that were isolated from mouse embryo), for examination of the effect of targeted 11beta-HSD1 inhibition on differentiation of 3T3-L1 cells. Differentiation was stimulated with 3-isobutyl-1-methyxanthine, insulin, and dexamethasone. The transcription level of the genes was detected by real-time PCR. RESULTS: Lipid accumulation was significantly inhibited in cells transfected with mouse 11beta-HSD1 siRNA compared with non-transfected 3T3-L1 cells. Fewer lipid droplets were detected in the transfected cells both prior to stimulation and after stimulation with differentiation-inducing reagents. The expression of adipocyte differentiation-associated markers such as lipoprotein lipase and fatty acid synthetase were downregulated in the transfected cells. Similarly, the expression of preadipocyte factor-1, an inhibitor of adipocyte differentiation, was downregulated upon stimulation of differentiation and had no changes in the transfected cells. CONCLUSION: 11 beta-HSD1 can promote preadipocyte differentiation. Based on this, we propose that 11 beta-HSD1 may be an important candidate mediator of obesity and obesity-induced insulin resistance.

Role of 11-beta-hydroxysteroid dehydrogenase type 1 in differentiation of 3T3-L1 cells and in rats with diet-induced obesity.

AIM: To observe the roles of 11-beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) in in vitro preadipocyte differentiation and in rats with diet-induced obesity (DIO). METHODS: Protein expression of 11beta-HSD1 in the process of 3T3-L1 cell differentiation and in various tissues of the rats were detected by Western blot analysis; expression of 11beta-HSD1 mRNA and glucocorticoid receptor (GR) and other marker genes of preadipocyte differentiation were detected by using real-time PCR. RESULTS: Lipid droplets in 3T3-L1 cells accumulated and increased after stimulation. A dramatically elevated protein level of 11beta-HSD1, especially in the late stages of 3T3-L1 cell differentiation, was detected. The relative mRNA levels of 11beta-HSD1, GR and cell differentiation markers LPL, aP2, and FAS were upregulated, and Pref-1 was downregulated during the differentiation. In DIO rats, bodyweight, visceral adipose mass index and the protein expression of 11beta-HSD1 increased, especially in adipose tissue, brain and muscles. Serum insulin, triglyceride, total cholesterol and low-density lipoprotein cholesterol were found to be increased in DIO rats, but without any obvious changes in blood glucose or tumor necrosis factor-alpha levels. CONCLUSION: 11beta-HSD1 may promote preadipocyte differentiation, and may be involved in the development of obesity.