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The neurohormone gonadotropin-releasing hormone (GnRH) plays an essential role in the control of reproductive functions in vertebrates. However, the full-length complementary DNA (cDNA) encoding the GnRHs precursor and it role in the reproductive cycles regulating has not been illustrated in crocodilian species. In the present study, full-length cDNAs encoding GnRH1 forms, its predominant localization within brain and peripheral tissues, and GnRH1 peptide concentrations in the hypothalamus and pituitary in relation to seasonal gonadal development of Chinese alligator were investigated. The cDNA of GnRH1 is consisted of 282 bp open reading frame encoding 93 amino acids. The deduced amino acid sequence of alligator GnRH1 contains several conserved regions and shows a closer genetic relationship to the avian species than to other reptile species. The GnRH1 immunopositive cells were not only detected widely in cerebrum, diencephalon, medulla oblongata but also observed in peripheral tissues, these widespread distribution characteristics indicated that GnRH1 possibly possess the multi-functionality in Chinese Alligator. GnRH1 peptide concentration within hypothalamus were observed be the highest in RP group (P 0.05), in association with an peak value in GSI and emerging of late vitellogenic follicles in the ovary. Taken together, our results suggested that GnRH1 was predominantly involved in the vitellogenesis process of seasonal gonadal development of Chinese Alligator.

Kisspeptin1 (Kiss1), a product of the Kiss1 gene, plays an important role in the regulation of reproduction in vertebrates by activating the Kiss1 receptor (Kiss1R) and its coexpression with gonadotrophin-releasing hormone (GnRH) in GnRH neurons. The purpose of this study was to clone the Kiss1 and Kiss1R genes found in the brain of Alligator sinensis and to explore their relationship with reproduction. The full-length cDNA of Kiss1 is 816bp, the open reading frame (ORF) is 417bp and the gene encodes a 138-amino acid precursor protein. The full-length cDNA of Kiss1R is 2348bp, the ORF is 1086bp and the gene encodes a 361-amino acid protein. Quantitative polymerase chain reaction showed that, except for Kiss1R expression in the hypothalamus, the expression of Kiss1 and Kiss1Rduring the reproductive period of A. sinensis was higher than that in the hypothalamus, pituitary gland and ovary during the hibernation period. The changes in GnRH2 mRNA in the hypothalamus were similar to those of GnRH1 and peaked during the reproductive period. This study confirms the existence of Kiss1 and Kiss1R in A. sinensis and the findings strongly suggest that Kiss1 and Kiss1R may participate in the regulation of GnRH secretion in the hypothalamus of alligators during the reproductive period. Furthermore, this is the first report of the full-length cDNA sequences of Kiss1 and Kiss1R in reptiles.

Background— Multiple genetic loci associated with lipid levels have been identified predominantly in Europeans, and the issue of to what extent these genetic loci can predict blood lipid levels increases over time and the incidence of future hyperlipidemia remains largely unknown. Methods and Results— We conducted a meta-analysis of genome-wide association studies of lipid levels in 8344 subjects followed by replication studies including 14 739 additional individuals. We replicated 17 previously reported loci. We also newly identified 3 Chinese-specific variants in previous regions ( HLA-C , LIPG , and LDLR ) with genome-wide significance. Almost all the variants contributed to lipid levels change and incident hyperlipidemia >8.1-year follow-up among 6428 individuals of a prospective cohort study. The strongest associations for lipid levels change were detected at LPL , TRIB1 , APOA1-C3-A4-A5 , LIPC , CETP , and LDLR ( P range from 4.84×10 −4 to 4.62×10 −18 ), whereas LPL , TRIB1 , ABCA1 , APOA1-C3-A4-A5 , CETP , and APOE displayed significant strongest associations for incident hyperlipidemia ( P range from 1.20×10 −3 to 4.67×10 −16 ). The 4 lipids genetic risk scores were independently associated with linear increases in their corresponding lipid levels and risk of incident hyperlipidemia. A C -statistics analysis showed significant improvement in the prediction of incident hyperlipidemia on top of traditional risk factors including the baseline lipid levels. Conclusions— These findings identified some evidence for allelic heterogeneity in Chinese when compared with Europeans in relation to lipid associations. The individual variants and those cumulative effects were independent risk factors for lipids increase and incident hyperlipidemia.

Sex steroid hormones play an important role in mediating physiological responses and developmental processes through their receptors across all vertebrates. Chinese alligator (Alligator sinensis) is a critically endangered reptile species unique to China. In this study, we have cloned one of the sex steroid hormone receptor genes, androgen receptor (AR) from the brain of Chinese alligator for the first time. The full-length AR cDNA is 2717 bp in length with an open reading frame (ORF) encoding 722 amino acids. Amino acid alignment analyses indicated that the ARs exhibit highly conserved functional domains. Especially, the P-box and D-box, which are essential to ensure that receptor binding to the androgen response elements, are completely conserved in selected species. Using the quantitative real-time PCR (qPCR), the spatial expression of four receptor mRNAs in all newborn brain tissues and temporal expression of them in the cerebrum during the embryonic development in Chinese alligators were investigated. The results of qPCR showed ubiquitous expression of the four receptor mRNAs in all newborn brain tissues examined and significant changes in the expression levels of these receptor mRNAs in the embryonic development. These results suggest that sex steroid hormones might play an important role in the regulation of complex neuroendocrine activities in newborn Chinese alligator. Furthermore, these data provide an important foundation for further studies on endocrinology and molecular biology of non-mammalian sex steroid hormone receptors.

Crocodilians are regarded as possessing a powerful immune system. However, the composition and action of the crocodilian immune system have remained unclear until now. Cathelicidins, the principal family of host defense peptides, play pivotal roles in vertebrate immune defense against microbial invasions. However, cathelicidins from crocodilians have not been extensively studied to date. In the present study, six novel cathelicidins (As-CATH1-6) were identified and characterized from the endangered Chinese alligator (

Hypertension is a common disorder and the leading risk factor for cardiovascular disease and premature deaths worldwide. Genome-wide association studies (GWASs) in the European population have identified multiple chromosomal regions associated with blood pressure, and the identified loci altogether explain only a small fraction of the variance for blood pressure. The differences in environmental exposures and genetic background between Chinese and European populations might suggest potential different pathways of blood pressure regulation. To identify novel genetic variants affecting blood pressure variation, we conducted a meta-analysis of GWASs of blood pressure and hypertension in 11 816 subjects followed by replication studies including 69 146 additional individuals. We identified genome-wide significant (P < 5.0 x 10(-8)) associations with blood pressure, which included variants at three new loci (CACNA1D, CYP21A2, and MED13L) and a newly discovered variant near SLC4A7. We also replicated 14 previously reported loci, 8 (CASZ1, MOV10, FGF5, CYP17A1, SOX6, ATP2B1, ALDH2, and JAG1) at genome-wide significance, and 6 (FIGN, ULK4, GUCY1A3, HFE, TBX3-TBX5, and TBX3) at a suggestive level of P = 1.81 x 10(-3) to 5.16 x 10(-8). These findings provide new mechanistic insights into the regulation of blood pressure and potential targets for treatments.

Objectives Acute aortic dissection (AAD) is a severe clinical emergency with a high mortality, and is easily misdiagnosed in its early stage. This study aimed at discovering serum metabolomic markers with the potential to diagnose AAD and distinguish between two subtypes of AAD. Methods Thirty-five patients with AAD, including 20 with Stanford type A and 15 with Stanford type B were enrolled in this study, together with 20 healthy controls. All patients with AAD were admitted within 72 h of onset. Serum metabolomics profiles were determined by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry and the data were analysed by principal component analysis and partial least squares discriminant analysis. Results A total of 17 metabolites differing between the control and AAD groups were finally screened and identified as lysophosphatidylcholines (LPC) and sphingolipids including sphinganine, phytosphingosine, sphingomyelin, and ceramide. Compared with those in the healthy control group, LPC levels were significantly lower in both the Stanford type A and type B AAD groups. Interestingly, sphingolipids, including sphinganine, phytosphingosine, and ceramide, were remarkably reduced in the Stanford type A AAD group, but not in the Stanford type B AAD group. Subgroup analysis showed that the changes in LPC and sphingolipid levels were unrelated to hypertension or gender. Conclusions The present results indicate that LPCs and sphingolipids are significantly altered in patients with AAD, and several sphingolipids, such as sphinganine, phytosphingosine, and ceramide, were dramatically decreased in patients with Stanford type A AAD. A combination of these two families of metabolites could serve as a potential biomarker for the diagnosis of AAD and distinguishing between Stanford type A and Stanford type B.

High dietary sodium and low potassium intake have been related to increased blood pressure (BP) in animal experiments, observational epidemiologic studies, and randomized controlled clinical trials.1–3 However, BP responses to dietary sodium and potassium intake vary considerably among individuals.2,4–6 The increased BP response to sodium, also known as salt sensitivity, has been associated with an increased risk of hypertension, cardiovascular disease, and premature death.7,8 The cold pressor test (CPT), which measures BP response to the stimulus of external cold, has been used for the evaluation of cardiovascular reactivity to stress in normotensive and hypertensive subjects. Cardiovascular hyper-reactivity to stress has been related to the development of hypertension and cardiovascular disease.9–11 In addition, increased BP response to the CPT has been associated with greater BP responses to changes in dietary sodium and potassium intake.12 Previous studies have indicated that both genetic and environmental factors may contribute to BP responses to dietary sodium and potassium intake and to the CPT.13–17 The Genetic Epidemiology Network of Salt Sensitivity (GenSalt) study aimed to investigate genetic factors related to BP responses to dietary sodium and potassium interventions, as well as the CPT.18 The study participant recruitment, dietary intervention, and data collection were conducted between October 2003 and July 2005. The study used a family-based feeding study design, and each family was ascertained through a proband with untreated prehypertension or stage 1 hypertension. Families of those with hypertension are most likely enriched in genetic variants for hypertension and tend to be more sensitive to dietary sodium and potassium interventions and the CPT. This design should potentially maximize the study power for identifying genetic variants for BP responses to dietary sodium and potassium intake and the CPT. A total of 1,906 study participants from 633 families took part in a 21-day dietary intervention including a 7-day low-sodium feeding, a 7-day high-sodium feeding, and a 7-day high-sodium feeding with potassium supplementation. The GenSalt study observed that BP responses to dietary sodium and potassium interventions and the CPT varied greatly among individuals.19 The GenSalt study also indicated that the heritabilities for BP responses to dietary sodium and potassium interventions and to the CPT were moderate, ranging 0.24–0.42.14 Novel genetic variants have been identified that are associated with BP responses among the GenSalt study population.20–28 To replicate and validate significant findings of the GenSalt study, we recruited an independent sample from rural north China and conducted the same measurements and interventions as the GenSalt study. Here we present the detailed design and methods of the GenSalt replication study, as well as the baseline characteristics and blood pressure responses to the dietary sodium and potassium interventions and the CPT.

Although multiple genetic markers associated with blood pressure have been identified by genome-wide association studies, their aggregate effect on risk of incident hypertension and cardiovascular disease is uncertain, particularly among East Asian who may have different genetic and environmental exposures from Europeans. We aimed to examine the association between genetic predisposition to higher blood pressure and risk of incident hypertension and cardiovascular disease in 26 262 individuals in 2 Chinese population-based prospective cohorts. A genetic risk score was calculated based on 22 established variants for blood pressure in East Asian. We found the genetic risk score was significantly and independently associated with linear increases in blood pressure and risk of incident hypertension and cardiovascular disease ( P range from 4.57×10 –3 to 3.10×10 –6 ). In analyses adjusted for traditional risk factors including blood pressure, individuals carrying most blood pressure–related risk alleles (top quintile of genetic score distribution) had 40% (95% confidence interval, 18–66) and 26% (6–45) increased risk for incident hypertension and cardiovascular disease, respectively, when compared with individuals in the bottom quintile. The genetic risk score also significantly improved discrimination for incident hypertension and cardiovascular disease and led to modest improvements in risk reclassification for cardiovascular disease (all the P

Background— Blood pressure (BP) responses to dietary sodium and potassium intervention and cold pressor test vary considerably among individuals. We aimed to identify novel genetic variants influencing individuals’ BP responses to dietary intervention and cold pressor test. Methods and Results— We conducted a genome-wide association study of BP responses in 1881 Han Chinese and de novo genotyped top findings in 698 Han Chinese. Diet-feeding study included a 7-day low-sodium (51.3 mmol/d), a 7-day high-sodium (307.8 mmol/d), and a 7-day high-sodium plus potassium supplementation (60 mmol/d). Nine BP measurements were obtained during baseline observation and each intervention period. The meta-analyses identified 8 novel loci for BP phenotypes, which physically mapped in or near PRMT6 ( P =7.29×10 –9 ), CDCA7 ( P =3.57×10 –8 ), PIBF1 ( P =1.78×10 –9 ), ARL4C ( P =1.86×10 –8 ), IRAK1BP1 ( P =1.44×10 −10 ), SALL1 ( P =7.01×10 –13 ), TRPM8 ( P =2.68×10 –8 ), and FBXL13 ( P =3.74×10 –9 ). There was a strong dose–response relationship between the number of risk alleles of these independent single-nucleotide polymorphisms and the risk of developing hypertension during the 7.5-year follow-up in the study participants. Compared with those in the lowest quartile of risk alleles, odds ratios (95% confidence intervals) for those in the second, third, and fourth quartiles were 1.39 (0.97, 1.99), 1.72 (1.19, 2.47), and 1.84 (1.29, 2.62), respectively ( P =0.0003 for trend). Conclusions— Our study identified 8 novel loci for BP responses to dietary sodium and potassium intervention and cold pressor test. The effect size of these novel loci on BP phenotypes is much larger than those reported by the previously published studies. Furthermore, these variants predict the risk of developing hypertension among individuals with normal BP at baseline.

To investigate and compare Trp64Arg mutation of beta(3)-adrenergic receptor (beta(3)-AR) gene in simple obesity and metabolic syndrome (MS), and to correlate the mutation difference with sex, total body fat and fat distribution.Mutation study was carried out with PCR in 295 subjects with simple obesity and 219 subjects with MS. The subjects were stratified by body mass index (BMI) as light obesity group (BMI 25 approximately 29.9 kg/m(2)) and serious obesity group (BMI/= 30 kg/m(2)) and by mean of waist circumference (WC) as abdominal adipose tissue light depot group (WC104 cm in male and WC88 cm in female) and serious depot group (WC/= 104 cm in male and WC/= 88 cm in female). 175 healthy non-obese subjects were selected as controls.The frequency of Trp64Arg mutation of beta(3)-AR gene was higher in the male subjects with MS than those with simple obesity and non-obese controls (32.25%, 21.01% and 19.91%, respectively, P0.05) and also higher than female ones with MS (32.35% vs 23.46%, P0.01). It was found by further stratification that the frequency of Trp64Arg mutation of beta(3)-AR gene was higher in the male light obesity group with MS than female light obesity group with MS. The frequency is also higher than that in the male light obesity group of the obese subjects (32.83% vs 17.35%, P0.05 and 32.83% vs 20.41%, P0.05, respectively). The frequency of mutation was higher in male abdominal adipose tissue serious depot subjects with MS than those with simple obesity (35.71% vs 20.16%, P0.05).Trp64Arg mutation of beta(3)-AR gene may be used as a genetic marker for MS in male.

Crocodilians are quite vocal relative to other reptile groups, and the alligators are among the most vocal of the crocodilians. The Chinese alligator, Alligator sinensis, is usually solitary but engages in bellowing choruses in certain waters during the mating season. This paper reports the organization of Chinese alligator's bellowing choruses based upon field observations and playback experiments. Alligators of both genders engaged in the choruses, remaining immobile throughout and inclining toward bellowing synchronously (i.e., starting and finishing at about the same time). The choruses lasted about 10 min with abrupt onset and offset. Moreover, playback experiments revealed that both male and female alligators responded equally to bellowing stimuli from the same and opposite sexes and that none of the tested alligators approached the loudspeaker in spite of playback of male or female stimuli. These suggest that Chinese alligators may not bellow to compete for or attract mates during the choruses. Instead, when their ecological behaviors, namely, dispersed inhabitation, multi-copulation, restricted mating season, etc., are considered, we hypothesize that they may synchronize bellows to enhance group detectability for assembling individuals into certain waters for subsequent copulations.