Endocrine and developmental correlates of unilateral cryptorchidism in a wild baboon

A wild, group-living 8.5-year-old adult baboon was found to have only a single palpable testicle, the only case of cryptorchidism found among more than 200 males that we have examined. This young adult had an unusually small body size for his age, one that was comparable to that of immature males two years younger, and during maturation his body mass was increasingly small for his age. As a young adult, he also had very low testosterone concentrations, which, in combination with his small size, history of impaired growth, and the absence of any obvious scars around the scrotum, suggest that this is a case of spontaneous unilateral cryptorchidism of unknown cause rather than one of monorchidism arising from injury. Despite striking differences in his growth, adult body size, and testosterone levels, the male's cryptorchidism seemed to have relatively little effect on his social and sexual maturation in his natal group. Nonetheless, it may be related to his inability to gain entry into another group after dispersal.     

The Association of the CYP19 and CYP17 Polymorphic Markers with Sporadic Breast Cancer

Polymorphic alleles of CYP17 and CYP19, which are involved in estrogen biosynthesis, were tested for association with breast cancer (BC). Microsatellite (TTTA)_n and 3-bp deletion of CYP19 and single-nucleotide polymorphism T27C of CYP17 were analyzed in 123 BC patients and 119 healthy women. Of the six (TTTA)_n alleles observed, allele (TTTA)₈ proved to be associated with BC (11.8% vs. 6.3%, P = 0.04). Genotype A2/A2 of CYP17 was also associated with BC (32.5% vs. 20.2%, P = 0.04). Risk of BC was especially high in the presence of both factors (7.3% vs. 0%, P < 0.01). Allele (TTTA)₈ and genotype A2/A2 were assumed to be risk factors of BC.     

Effect of orexin B on CYP17A1 and CYP19A3 expression and oestradiol,oestrone and testosterone secretion in the porcine uterus during early pregnancy and the oestrous cycle

Orexin A (OXA) and B (OXB) are hypothalamic neuropeptides identified as regulators of food intake, energy homoeostasis, sleep–wake cycle and arousal. They also create an integrative link between energy homoeostasis and reproduction. Although their functions in the ovaries and testes have been partially explored, to date, less attention has been focused on the role of the peptides in the uterus. The aim of this study was to investigate the effect of one of orexins – orexin B on oestradiol (E₂), oestrone (E₁) and testosterone (T) secretion by porcine endometrial and myometrial slices as well as the gene expression of key steroidogenic enzymes responsible for steroid production (CYP17A1, CYP19A3) during the luteal phase of the oestrous cycle (days 10 to 11) and early pregnancy (days 10 to 11, 12 to 13, 15 to 16, 27 to 28). Orexin B suppressed E₂ secretion by endometrial slices on days 10 to 11 and 15 to 16 of pregnancy, and days 10 to 11 of the cycle. In the myometrium, OXB inhibited E₂ production on days 10 to 11 of pregnancy, whereas on days 12 to 13 it enhanced steroid output. Endometrial E₁ release was potentiated by the peptide during all studied periods of the cycle and pregnancy, with the exception of days 12 to 13, when an inhibitory effect was observed. Myometrial secretion of E₁ was increased, except on days 27 to 28. Testosterone secretion by endometrial slices was increased on days 12 to 13 and 27 to 28 of pregnancy. On days 10 to 11 of the cycle, T release was stimulated in response to the lowest and decreased under the influence of the highest dose of OXB. In the myometrium, T production was inhibited by OXB on days 10 to 11 of pregnancy and during the corresponding period of the cycle. On days 27 to 28 of pregnancy, T release was potentiated by the lowest dose of OXB. Expression of both genes was modified by OXB depending on the period of pregnancy and the type of examined uterine tissues. Our findings suggest that OXB, through modulation of uterine steroidogenesis, may have a regulatory role in the uterus.     

Altered expression and function of regulator of G-protein signaling-17 (RGS17) in hepatocellular carcinoma

Guanine nucleotide regulatory proteins (G-proteins) are central to normal hepatocyte function and are implicated in hepatic disease initiation and progression. Regulators of G-protein signaling (RGS) are critical to defining G-protein-dependent signal fidelity, yet the role of RGS proteins in the liver is poorly defined. The aims of this study were to determine RGS17 expression in normal and transformed hepatic tissue and cells, and address the function of RGS17 in hepatic tumorgenicity. RGS17 expression was determined in human and rat HCC tissue and cell lines. Molecular approaches were used to alter RGS17 expression in HCC cells, effects on cell function measured, and RGS17 association with specific Gα-subunits determined. Using these approaches RGS17 mRNA, but not protein, was detectable in human and rat HCC tissue and cells. Conversely, RGS17 mRNA was not detected in normal tissue, isolated hepatocytes, or non-tumorigenic hepatic cells. Subsequent studies using transfected cells demonstrated that RGS17 proteins were not post-translationally modified in HCC cells, and RGS17 expression is governed by protein degradation and not via miRNAs. Notwithstanding inherently low RGS17 protein levels, altering RGS17 expression profoundly affected HCC cell mitogenesis and migration. Analysis of RGS17-G-protein interaction demonstrated RGS17 associates with both Giα- and Gqα-subunits in HCC cells of human and rat origin. In conclusion, these data demonstrate that, despite difficulties in measuring endogenous RGS protein expression, RGS17 is differentially expressed in HCC and plays a central role in regulating transformed hepatocyte tumorgenicity.     

Deep sequencing of a candidate region harboring the SOX9 gene for the canine XX disorder of sex development

A disorder of sex development (DSD) in dogs with female sex chromosomes (78, XX), a lack of the SRY gene and the presence of testes or ovotestes is commonly diagnosed in numerous breeds. The molecular background of DSD is not fully recognized but has been linked to the copy number variation in the region harboring the SOX9 gene. We applied a genome‐wide association study and targeted next‐generation sequencing techniques to compare DSD and normal female dogs. The genome‐wide association study did not indicate a significant chromosome region. Targeted next‐generation sequencing of a 1.5‐Mb region on canine chromosome 9 harboring the SOX9 gene revealed two putatively DSD‐associated copy number variations 355 kb upstream and 691 kb downstream of SOX9, four blocks of low polymorphism and two blocks of an elevated heterozygosity. An initial next‐generation sequencing analysis showed an association with two SNPs, but validation in larger cohorts did not confirm this result. We identified a large homologous fragment (over 243.8 kb), named hfMAGI2, located upstream of SOX9, that overlaps a known copy number variation region. It shows a high sequence similarity with the 5′ flanking region of the MAGI2 gene located on canine chromosome 18 that encodes a protein involved in ovary formation during early embryonic development. Our study showed that the identified copy number variation region located upstream of the SOX9 gene contains potential regulatory sequences (long non‐coding RNA and hfMAGI2) and led to the assumption that a multiplication of this element may alter expression of the SOX9 gene, triggering the DSD phenotype.     

Characterization of CYP1A2, CYP2C19, CYP3A4 and CYP3A5 polymorphisms in South Brazilians

Potential causes of variability in drug response include intrinsic factors such as ethnicity and genetic differences in the expression of enzymes that metabolize drugs, such as those from Cytochrome P450 (CYPs) superfamily. Pharmacogenetic studies search for genetic differences between populations since relevant alleles occur with varying frequencies among different ethnic populations. The Brazilian population is one of the most heterogeneous in the world, resulting from multiethnic admixture of Amerindians, Europeans, and Africans across centuries. Since the knowledge of CYP allele frequency distributions is relevant to pharmacogenetic strategies and these data are scarce in the Brazilian population, this study aimed to describe genotype and allele distributions of 15 single nucleotide polymorphisms (SNPs) at CYP 1A2, 2C19, 3A4, and 3A5 genes in African and European descents from South Brazil. A sample of 179 healthy individuals of European and African ancestry was genotyped by the MassARRAY SNP genotyping system. CYP3A5*3, CYP1A2*1F, CYP3A4*1B, and CYP2C19*2 were the most frequent alleles found in our sample. Significant differences in genotype and allelic distribution between African and European descents were observed for CYP3A4 and CYP3A5 genes. CYP3A4*1B was observed in higher frequency in African descents (0.379) than in European descents (0.098), and European descents showed higher frequency of CYP3A5*3 (0.810) than African descents (0.523). Our results indicate that only a few polymorphisms would have impact in pharmacogenetic testing in South Brazilians. Further studies with larger sample sizes are required also among other Brazilian regions.     

Altered expression of hepatic CYP2E1 and CYP4A in obese, diabetic ob/ob mice, and fa/fa Zucker rats

Hepatic levels of the cytochrome P450 (CYP) proteins 2E1 and 4A are often increased in obesity, diabetes and fasting. In such states of nutritional imbalance, CYPs 2E1 and 4A may play a more significant role in fatty acid oxidation. In order to more fully characterize the regulation of CYP2E1 and CYP4A in obesity and obesity-related (type II) diabetes, we analyzed the hepatic expression of CYP2E1 and CYP4A in ob/ob mice which are leptin deficient, and fa/fa Zucker rats which have defective leptin receptor function. CYP2E1 protein and mRNA were either unchanged or reduced in both models. Conversely, expression of murine Cyp4a10 and 4a14 in the obese mice, and 4A2 in the male fatty Zucker rat, were greatly increased. The levels of other CYP4As were either unchanged or reduced. These results show that CYP2E1 is not inevitably increased by obesity and diabetes and indicate differential regulation of CYP4A subfamily genes in rodent models. Further, they implicate leptin receptor signaling as a factor that may modulate expression of CYP gene products involved in fatty acid oxidation.     

DEHP对中国林蛙精巢中StAR、CYP17和CYP19基因表达的影响

为探讨邻苯二甲酸二(2-乙基己基)酯(di-2-ethylhexyl phthalate,DEHP)对两栖动物精巢类固醇激素合成的影响,将中国林蛙(Rana chensinensis)雄性成体分别暴露于浓度为10-7、10-6、10-5、10-4mol·L-1DEHP的水体,分别在暴露20、30和40d取其精巢,提取精巢总RNA,逆转录合成cDNA,通过荧光实时定量PCR检测StAR、CYP17和CYP19mRNA表达相对值。结果表明:与对照组相比,DEHP处理组StAR和CYP19基因表达均上调,CYP17基因表达下调;比较不同DEHP浓度和不同暴露时间对StAR、CYP17和CYP19mRNA表达相对值的影响,显示DEHP浓度变化对3个基因表达影响的规律性不强,而DEHP暴露时间的累积效应较明显;提示DEHP可通过干扰中国林蛙精巢中StAR、CYP17和CYP19基因表达,影响其相应关键酶的表达,从而干扰类固醇激素的合成,产生雌激素效应。     

飞蝗CYP408B1和CYP409A1基因的原核表达

【目的】细胞色素P450是分布极其广泛的超家族酶,在昆虫内源及外源化合物代谢中发挥着重要的作用。本文分析了飞蝗Locusta migratoria CYP408B1和CYP409A1基因在不同组织部位的表达差异,并对两种蛋白进行原核表达,为其分子特性和生物学功能的深入研究提供基础资料。【方法】提取飞蝗5龄若虫不同组织部位的总RNA,体外反转录成c DNA,采用Real-time PCR和RT-PCR技术分析飞蝗CYP408B1和CYP409A1在不同组织部位的表达模式,构建表达载体p CW/CYP408B1、p CW/CYP409A1和p AC/CPR,将p CW/CYP408B1和p CW/CYP409A1分别与p AC/CPR在大肠杆菌Escherichia coli BL21(DE3)中进行共表达。【结果】通过PCR检测,发现CYP408B1和CYP409A1在飞蝗5龄若虫触角、脑、视叶、咽下神经节、胸神经节和附腺中均有表达,其中CYP408B1在附腺中表达量较高。原核表达结果显示,CYP409A1和CPR(NADPH细胞色素P450还原酶)均可表达,蛋白分子量分别约为58 ku和77 ku,但均为包涵体,而CYP408B1未能成功表达。【结论】本文揭示了飞蝗CYP408B1和CYP409A1在不同组织部位的表达模式,并对CYP409A1和CPR进行了原核表达,研究结果为深入探讨飞蝗细胞色素P450基因对杀虫剂的代谢解毒作用提供了实验依据和基础资料。     

Association of serum sex steroid levels and bone mineral density with CYP17 and CYP19 gene polymorphisms in postmenopausal women in Turkey

Many clinical conditions, including osteoporosis, are associated with serum levels of sex steroids. Enzymes that regulate rate-limiting steps of steroidogenic pathways, such as CYP17 and CYP19, are also regarded as significant factors that may cause the development of these conditions. We investigated the association of two common polymorphisms, in the promoter region (T→C substitution) of CYP17 and exon 3 (G→A) of CYP19, with bone mineral density (BMD) in the lumbar spine and femoral neck and serum androgen/estradiol, in a case-control study of 172 postmenopausal women aged 62.3 ± 9.6 years (mean ± SD). The CYP17 TC genotype was significantly overrepresented in patients compared to controls, and TC genotype neck T-score and lumbar T-score values were significantly higher in patients compared to controls. CYP17 TC and TT genotype testosterone and DHEA-SO(4) levels were lower in patients compared to controls. All three genotypes of CYP19 had almost the same distribution among patients. The CYP19 AG genotype, however, was most frequent among controls. CYP19 lumbar BMD levels were close to each other among the different genotypes; however, AA and AG genotypes were significantly lower in patients. Testosterone and DHEA-SO(4) levels in the CYP19 GG genotype were higher compared to those of the other genotypes in patients but not in controls. CYP19 GA individuals had lower E(2) levels and lower BMD in controls and patients. Femoral neck BMD and lumbar T-score were also diminished with GA transition. In conclusion, CYP17 and CYP19 gene polymorphisms were found to be associated with osteoporosis in postmenopausal women in Turkey.