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We critically evaluate an article published in the Journal of Law, Medicine & Ethics by Svoboda, Adler and Van Howe (1) challenging the validity of the American Academy of Pediatrics [...]

FOXO3 is a ubiquitous transcription factor expressed in response to cellular stress caused by nutrient deprivation, inflammatory cytokines, reactive oxygen species, radiation, hypoxia, and other factors. We showed previously that the association of inherited FOXO3variants with longevity was the result of partial protection against mortality risk posed by aging-related life-long stressors, particularly cardiometabolic disease. We then referred to the longevity-associated genotypes as conferring “mortality resilience.” Serum proteins whose levels change with aging and are associated with mortality risk may be considered as “stress proteins.” They may serve as indirect measures of life-long stress. Our aims were to (1) identify stress proteins that increase with aging and are associated with an increased risk of mortality, and (2) to determine if FOXO3longevity/resilience genotype dampens the expected increase in mortality risk they pose. A total of 4500 serum protein aptamers were quantified using the Somalogic SomaScan proteomics platform in the current study of 975 men aged 71–83 years. Stress proteins associated with mortality were identified. We then used age-adjusted multivariable Cox models to investigate the interaction of stress protein with FOXO3longevity-associated rs12212067genotypes. For all the analyses, the pvalues were corrected for multiple comparisons by false discovery rate. This led to the identification of 44 stress proteins influencing the association of FOXO3genotype with reduced mortality. Biological pathways were identified for these proteins. Our results suggest that the FOXO3resilience genotype functions by reducing mortality in pathways related to innate immunity, bone morphogenetic protein signaling, leukocyte migration, and growth factor response.

ADAM V. BENJAFIELD [1] CHERYL L. GLENN XING LI WANG [2,4,5] STEPHEN COLAGIURI [3] BRIAN J. MORRIS [1] OBJECTIVE -- Genetic variation in the tumor necrosis factor (TNF) receptor 2 [...]

A possible link between the glucocorticoid receptor gene (GRL, 5q31-q32) and overweight has been suggested in a study of 42 families with morbid obesity.[1] Data from another small study--of pairs [...]

Introduction:Hypertension is a pathophysiological stress. Growth differentiation factor 15 (GDF15) is a stress-response protein, and a predictor for heart disease. The effects of the longevity genotype of FOXO3, a stress-response and prominent longevity-associated gene, on mortality vary in normotensive and hypertensive men.Hypothesis:The effect of GDF15 concentration on the risk of incident coronary heart disease (CHD) is different in men with different hypertension status.Methods:The Kuakini Honolulu Heart Program (KHHP) is a longitudinal study of cardiovascular diseases that started in 1965 involving 8,006 Japanese-American men in Hawaii. Proteomic analyses were performed using serum from KHHP exam 4 (1991-1993, ages 71-93) in a random sample (n=1,000) of men who in mid-life had been free of chronic diseases such as CHD, stroke, cancer, and diabetes. Participants were followed for incident CHD event (first event of MI, coronary insufficiency, angina, CABG, angioplasty, silent MI and CHD death) through December 1999. The Cox proportional hazards model was used to assess potential association of GDF15 concentration and hypertension (SBP/DBP≥160/95 mmHg or on anti-hypertensives) with incident CHD.Results:We excluded 5 men missing GDF15 data and 221 men with diseases including CHD, CHF, atrial fibrillation, LVH and stroke at baseline (KHHP exam 4). During 9 years of follow-up (median 7.92 years), 60 men developed CHD. To eliminate the possible recursive-effect of preclinical CHD on GDF15 at baseline, 6 CHD cases diagnosed within the first year of follow-up were excluded. So, there were 768 men available for analysis. Participants were divided, using tertiles of GDF15 concentration, into two groups: low-medium GDF15 (in low or middle tertile) and high GDF15 (in upper tertile). Multivariate Cox model adjusting for age, BMI, smoking (pack-years), cholesterol, HDL, diabetes and serum glucose showed a significant interaction effect of hypertension and high GDF15 on incident CHD (p=0.019); HR (95%CI) of high GDF15 vs low-medium GDF15 on CHD was 4.56 (1.51-13.76; p=0.007) in normotensive men, and 0.97 (0.49-1.92; p=0.93) in hypertensive men.Conclusions:High GDF15 concentration increases CHD risk in normotensive men, but not in hypertensive men.

The objective of this review was to assess the trend in the US male circumcision rate and the impact that the affirmative 2012 American Academy of Pediatrics policy statement might have on neonatal circumcision practice. We searched PubMed for the term circumcisionto retrieve relevant articles. This review was prompted by a recent report by the Centers for Disease Control and Prevention that found a slight increase, from 79% to 81%, in the prevalence of circumcision in males aged 14 to 59 years during the past decade. There were racial and ethnic disparities, with prevalence rising to 91% in white, 76% in black, and 44% in Hispanic males. Because data on neonatal circumcision are equivocal, we undertook a critical analysis of hospital discharge data. After correction for underreporting, we found that the percentage had declined from 83% in the 1960s to 77% by 2010. A risk-benefit analysis of conditions that neonatal circumcision protects against revealed that benefits exceed risks by at least 100 to 1 and that over their lifetime, half of uncircumcised males will require treatment for a medical condition associated with retention of the foreskin. Other analyses show that neonatal male circumcision is cost-effective for disease prevention. The benefits of circumcision begin in the neonatal period by protection against infections that can damage the pediatric kidney. Given the substantial risk of adverse conditions and disease, some argue that failure to circumcise a baby boy may be unethical because it diminishes his right to good health. There is no long-term adverse effect of neonatal circumcision on sexual function or pleasure. The affirmative 2012 American Academy of Pediatrics policy supports parental education about, access to, and insurance and Medicaid coverage for elective infant circumcision. As with vaccination, circumcision of newborn boys should be part of public health policies. Campaigns should prioritize population subgroups with lower circumcision prevalence and a higher burden of diseases that can be ameliorated by circumcision.

In schizophrenia, subjects show reduced ability to evaluate and update risk/reward contingencies, showing correspondingly suboptimal performance in the Iowa gambling task. JNK signalling gene variants are associated with schizophrenia risk, and JNK modulates aspects of cognition. We therefore studied the performance of mice hemizygous for genetic deletion of the JNK activator MKK7 (Map2k7+/− mice) in a touchscreen version of the Iowa gambling task, additionally incorporating a novel contingency-switching stage. Map2k7+/− mice performed slightly better than wild-type (WT) littermates in acquisition and performance of the task. Although Map2k7+/− mice adapted well to subtle changes in risk/reward contingencies, they were profoundly impaired when the positions of ‘best’ and ‘worst’ choice selections were switched, and still avoided the previous ‘worst’ choice location weeks after the switch. This demonstrates a precise role for MKK7–JNK signalling in flexibility of risk/reward assessment and suggests that genetic variants affecting this molecular pathway may underlie impairment in this cognitive domain in schizophrenia. Importantly, this new contingency shift adaptation of the rodent touchscreen gambling task has translational utility for characterising these cognitive subprocesses in models of neuropsychiatric disorders.

The pseudoautosomal regions (PAR1 and PAR2) of the human X and Y chromosomes pair and recombine during meiosis. Thus genes in this region are not inherited in a strictly sex-linked fashion. PAR1 is located at the terminal region of the short arms and PAR2 at the tips of the long arms of these chromosomes. To date, 24 genes have been assigned to the PAR1 region. Half of these have a known function. In contrast, so far only 4 genes have been discovered in the PAR2 region. Deletion of the PAR1 region results in failure of pairing and male sterility. The gene SHOX (short stature homeobox-containing) resides in PAR1. SHOX haploinsufficiency contributes to certain features in Turner syndrome as well as the characteristics of Leri-Weill dyschondrosteosis. Only two of the human PAR1 genes have mouse homologues. These do not, however, reside in the mouse PAR1 region but are autosomal. The PAR regions seem to be relics of differential additions, losses, rearrangements and degradation of the X and Y chromosome in different mammalian lineages. Marsupials have three homologues of human PAR1 genes in their autosomes, although, in contrast to mouse, do not have a PAR region at all. The disappearance of PAR from other species seems likely and this region will only be rescued by the addition of genes to both X and Y, as has occurred already in lemmings. The present review summarizes the current understanding of the evolution of PAR and provides up-to-date information about individual genes residing in this region.

Objective:To conduct a critical peer‐review of the 2004 Policy Statement on routine male circumcision produced by the Royal Australasian College of Physicians (RACP). Method:Comprehensive evaluation in the context of the research field. Results:We find that the current Statement downplays the wide‐ranging life‐long benefits of circumcision in prevention of urinary tract infections (UTIs), penile and cervical cancer, genital herpes and chlamydia in women, HIV infection, phimosis, and various penile dermatoses, and at the same time overstates the complication rate. We highlight the many errors in the RACP Statement and note that it sidesteps making a conclusion based on circumcision's well‐documented prophylactic health benefits by instead referring to the status of the foreskin at birth. In the era of preventative medicine we view this as irresponsible. Conclusion:The RACP's Statement on routine male circumcision is not evidence‐based and should be retracted. Implications:In the interests of public health and individual well‐being an extensive, comprehensive, evidence‐based revision should be conducted so as to provide scientifically accurate, balanced information on the advantages, and also the low rate of mostly minor complications, associated with this simple procedure, which for maximum benefits and minimal risk should ideally be performed in the neonatal period.

Chromosome 1p36 has been linked to essential hypertension and systolic blood pressure. This locus contains the chloride channel-Kb gene (CLCNKB) and the tumour necrosis factor receptor 2 gene (TNFRSF1B). Polymorphisms of each of these have shown association with hypertension, and a CLCNKBT481S variant alters receptor function. Here we performed association studies in a well-characterized cohort of hypertensives and normotensives whose blood pressure status matched that of both their parents.

Although the quest for longevity is as old as civilization itself, only recently have technical and conceptual advances in genomics research brought us to the point of understanding the precise molecular events that make us age. This heralds an era when manipulations of these will enable us to live longer, healthier lives. The present review describes how recent experimental strategies have identified key genes and intracellular pathways that are responsible for ageing and longevity.

Objective:To perform association studies of polymorphisms of the potential candidate essential hypertension (HT) genes GRK4, PTP1Band HSD3B1.

The CYP11B2locus is an important candidate region in essential hypertension (HT). We therefore investigated CYP11B2polymorphisms T−344C, T4986C and A6547G for association with essential HT. This included haplotype analysis and measurement of plasma aldosterone levels.

Objective: To determine whether the N363S variant in the glucocorticoid receptor (encoded by nuclear receptor subfamily 3, group C, member 1: NR3C1) is associated with obesity, type 2 diabetes, or hypertension. Research Methods and Procedures: This was a cross‐sectional case‐control study involving 951 Anglo‐Celtic/Northern European subjects from Sydney. This study consisted of the following: 1) an obesity clinic group, most of whom had “morbid obesity” (mean BMI for group = 43 ± 8 kg/m2; n= 152); 2) a type 2 diabetes clinic group (n= 356); 3) patients with essential hypertension who had a strong family history (n= 141); and 4) normal healthy controls (n= 302). N363S genotype, BMI, and a range of other parameters relevant to each group were measured. Results: Compared with the frequency of 0.04 in nonobese healthy subjects, the S363allele was significantly higher in obesity clinic patients (0.17; p= 5.6 × 10−8), subjects with diabetes who were also obese (0.09; p= 0.0045), subjects with hypertension who were also overweight (0.08; p= 0.0016), and overweight healthy subjects (0.12; p= 0.0004). Discussion: The NR3C1N363S variant is associated with obesity and overweight in a range of patient settings but is not associated with hypertension or type 2 diabetes.

Glutamatergic and GABAergic neurotransmitter systems exist in equilibrium to maintain “normal” brain function. Evidence is accumulating that disturbance of this equilibrium may be one of the key factors giving rise to schizophrenia. While there is widespread evidence that the psychotomimetic phencyclidine (PCP) induces schizophrenia‐related symptoms, it is not clear how this dramatic effect is mediated. This study was designed to investigate acute and delayed effects of PCP on the mRNA expression of a range of markers of neuronal function associated with the glutamatergic and GABAergic systems within the rat brain. The mRNA levels of CaMKIIα, an enzyme which is located within the postsynaptic density and phosphorylates AMPA receptors, remained unaltered both 2 and 24 h posttreatment. Homer 1a, an immediate early gene associated with metabotropic glutamate receptors within the postsynaptic density, displayed region‐specific differential changes within the prefrontal, primary auditory, and retrosplenial cortices 2 and 24 h posttreatment. Parvalbumin, a calcium‐binding protein located within a subpopulation of GABAergic interneurones, displayed altered mRNA levels within the reticular nucleus of the thalamus at 2 and 24 h posttreatment and the substantia nigra pars reticulata 24 h posttreatment only. These phencyclidine‐induced changes in mRNA expression were not accompanied by any changes in hsp‐70 mRNA levels, a marker of NMDA antagonist‐induced reversible neurotoxicity. These results indicate that the glutamatergic (group I metabotropic glutamate receptors) and GABAergic (parvalbumin‐containing interneurones) neurotransmitter systems are differentially modulated in a region‐ and time‐dependent manner by exposure to phencyclidine. Synapse 46:206–214, 2002. © 2002 Wiley‐Liss, Inc.

Infection with microorganisms such as Helicobacter pylori and Chlamidia pneumoniae has been associated with coronary heart disease (CAD) and hypertension (HT). Infection increases the release of pro-inflammatory cytokines, thus facilitating interactions that lead to vascular damage and other effects. We hypothesized that genetically determined differences in activity or responsiveness of cytokine(s) might contribute to HT. The interleukin-1 gene (IL1) cluster on chromosome 2q14 contains three related genes (IL1A, IL1B, and IL1RN) located within a 430-kb region. These encode IL-1α and IL-1β, as well as their endogenous receptor antagonist, IL-1ra. The IL1RN gene has a penta-allelic 86-bp tandem repeat in intron 2. Allele IL1RN* 2 is associated with a wide range of chronic inflammatory and autoimmune conditions, and its combination with the − 31T variant of an IL1B C(− 31)T polymorphism constitutes a pro-inflammatory haplotype that leads to vigorous IL-1β production. We therefore tested each of these polymorphisms for association with HT. Subjects were white Anglo-Celtic residents of Sydney, Australia. Frequencies of IL1B C(− 31)T genotypes CC, CT, and TT were 0.50, 0.40, and 0.10 in normotensive (NT) and 0.46, 0.46, and 0.08 in HT, respectively (χ² = 1.2, P = 0.55). T allele frequency in NT (0.30) was similar to that in HT (0.31). For the IL1RN variant, frequencies of alleles IL1RN* 1 and * 2 and combined minor alleles * 3, * 4, and * 5 were 0.61, 0.36, and 0.03 in NT and 0.54, 0.36, and 0.10 in HT, respectively (χ² = 11, P = 0.004). In conclusion, no association of the IL1B C(− 31)T with HT was found, whereas combined frequency of the minor alleles of the IL1RN polymorphism was increased in the HT cohort studied. © 2001 Wiley-Liss, Inc.

Pathophysiological processes in coronary artery disease (CAD) are influenced by genetic factors. Since (i) inducible nitric oxide synthase (iNOS) has important cardiovascular effects, and (ii) the promoter of the iNOS gene (NOS2A) is genetically modulated by a 4 bp insertion/deletion (+/-) polymorphism located 0.7 kb upstream, we decided to examine the influence of this variant on clinical variables in 856 CAD patients of Anglo-Celtic/Northern European extraction. We found that 2% of CAD patients were homozygous for the + allele, and 19% were heterozygous. Males made up 74% of the patient group, and in these the + allele was associated with 38% higher plasma glucose levels (P = 0.005), a 4.8% elevation in the waist/hip ratio (P = 0.009) and a 48% greater frequency of unstable angina (P = 0.014). The + allele, by influencing iNOS expression, could thus contribute to indices of insulin resistance and angina severity in male CAD patients.

The neuronal cell adhesion molecule (NCAM) is a key mediator of structural plasticity in the central nervous system, but the mechanisms that control its expression are unknown. Equally, although the transcription factor NF-κB is present in the brain, few NF-κB-regulated genes relevant for central nervous system function have been identified. We have previously demonstrated that NF-κB is activated in neuronal cultures treated with kainic acid or nitric oxide. We show here that kainic acid or nitric oxide also increase the levels of NCAM mRNA and protein in neurons and that this induction of NCAM expression is sensitive to dexamethasone and to antisense, but not missense, oligonucleotides designed to suppress NF-κB synthesis. Nitric oxide also stimulates protein binding to an NF-κB site in the promoter of the NCAM gene. This indicates that NF-κB, which has recently been implicated in synaptic plasticity and also in the etiology of neurodegenerative disease, plays a crucial role in the activity-dependent regulation of NCAM gene expression. In addition, since both NCAM and NF-κB are present in the post-synaptic density, this represents a route allowing direct communication between the synapse and the nucleus.

The transcription factor NF-κB has been implicated in the synaptic plasticity and neurotoxicity mediated by ionotropic glutamate receptors in the striatum. However, the class of glutamate receptor and the intracellular pathways involved have not been determined. Kainate, but not AMPA or NMDA, was found to activate NF-κB in superfused slices of rat striatum. A similar activation was produced by the calcium ionophore A23187. The NF-κB activation by kainate was not observed in the absence of extracellular calcium, and was blocked by the p44/p42 MAP kinase inhibitor PD98059, but not by the p38 MAP kinase inhibitor SB203580. This demonstrates that striatal kainate receptors are coupled to NF-κB activation via calcium influx and p44/p42 MAP kinase activation.

A letter to the editor is presented in response to an article by Vivien Marx in the July 19, 2008 issue, which discusses male circumcision.

Linkage with essential hypertension has been claimed for a microsatellite marker near the angiotensinogen gene (AGT; chromosome 1q42), as has association for the AGT variants M235T, G(−6)A and A(−20)C. To more rigorously evaluate AGT as a candidate gene for hypertension we performed sibpair analysis with multiple microsatellite markers surrounding this locus and using more sophisticated analysis programs. We also performed an association study of the AGT variants in unrelated subjects with a strong family history (two affected parents). For the linkage study, single and multiplex polymerase chain reaction (PCRs) and automated genescan analysis were conducted on DNA from 175 Australian Anglo-Celtic Caucasian hypertensives for the following markers: D1S2880−(2.1 cM)−D1S213−(2.8 cM)−D1S251−(6.5 cM)−AGT−(2.0 cM) −D1S235. Statistical evaluation of genotype data by nonparametric methods resulted in the following scores: Single-point analysis − SPLINK, P > 0.18; APM method, P > 0.25; ASPEX, MLOD < 0.28; SIB-PAIR, P > 0.24; Multipoint analysis − MAPMAKER/SIBS, MLOD < 0.24; GENEHUNTER, P > 0.35. Exclusion scores of Lod −4.1 to −5.1 were obtained for these markers using MAPMAKER/SIBS for a λs of 1.6. The association study of G(−6)A, A(−20)C and M235T variants in 111 hypertensives with strong family history and 190 normotensives with no family history showed significant linkage disequilibrium between particular haplotypes, but we could find no association with hypertension. The present study therefore excludes AGT in the etiology of hypertension, at least in the population of Australian Anglo-Celtic Caucasians studied. Am. J. Med. Genet. 87:53–60, 1999. © 1999 Wiley-Liss, Inc.

Human papillomavirus infection currently is accepted as a major factor in the etiology of carcinoma of the cervix, vagina and vulva. While the nature of genital human papillomavirus infection in women is well documented, detailed knowledge of the disease in the male partners is lacking. Therefore, a prospective study was done to define the disease in the genitals of heterosexual men and to formulate an appropriate plan of management.

A small number of mRNA species are not restricted to the neuronal cell body, but are also present in neuronal dendrites. The levels of two of these dendritic mRNAs, encoding the microtubule‐associated protein MAP2 and the a subunit of calcium/calmodulin‐dependent protein kinase II (CamKllα), are increased rapidly by high‐frequency synaptic activity or by release of nitric oxide. To test the hypothesis that post‐transcriptional mechanisms might contribute to this modulation, primary cultures of rat hippocampal neurons were exposed to s‐nitroso‐N‐acetyl penicillamine (SNAP, 200 μM) or vehicle, and mRNA stability was determined. The stability of both CamKllá mRNA and MAP2 mRNA was increased by SNAP treatment, whereas the stabilities of tubulin T26 mRNA and proenkephalin mRNA were unaffected. When the intensity of staining for MAP2 immunoreactivity and CamKllα immunoreactivity was monitored in cultured hippocampal neurons, nitric oxide‐releasing agents induced increases in staining intensity that were dependent on protein synthesis but not on mRNA synthesis. These results show that nitric oxide can selectively stabilize CamKllα mRNA and MAP2 mRNA, leading to increased synthesis of the corresponding proteins. This demonstrates a mechanism whereby the presence of a particular mRNA in the vicinity of a synapse permits the levels of the protein product to be regulated by synaptic activity in a manner that is both prolonged and also highly localized to the region of stimulation. Thus, the dependence of sustained synaptic plasticity on de novoprotein synthesis need not entail a loss of anatomical specificity.

To assess the utility of a new, rapid, economical procedure that may prove valuable in cervical screening, Fourier transform infrared (ir) spectroscopy was performed on 25 cervicovaginal lavage specimens from women referred for colposcopy on the basis of a cytological abnormality detected on their Pap smear and whose lavage specimen was positive for human papillomavirus. Of the 18 classed as CIN I or less by histopathology, 11 showed band frequencies that deviated only slightly from spectra that characterize normal cervical cells and 3 of 5 "atypia" specimens had spectra identical to normal. Two of 3 classed as CIN II had spectra only slightly more abnormal to these 11. In the case of 2 graded as CIN I, several bands were similarly altered in the direction of the pattern seen for 4 CIN III specimens. A further CIN I sample gave a spectrum that was even further shifted toward the latter and the remaining CIN I sample had a pattern that matched the 4 CIN IIIs. The most obvious change in each of the CIN IIIs was an additional peak at 972 cm^-1 and this has been suggested as a key indicator for malignancy. One of the 3 CIN IIs had this peak. Other characteristic spectral changes were seen as well in the CIN III samples. High-risk HPV18 was present in 3 of the CIN III samples, as well as in one specimen classed as atypia, but having an abnormal ir spectrum. Low-risk HPV 6 or 11 was seen along in samples with a normal or slightly abnormal ir spectrum, but never in those that showed an ir pattern that was abnormal. The current study has therefore shown complete concordance between ir spectral findings and histopathology result in the case of CIN III specimens, but less precise matching for other grades of CIN. The spectral differences revealed by ir spectroscopy are likely to characterize molecular abnormalities in cervical cells during progression to cancer and may therefore have potential in assisting with clinical decision making. More studies will, however, be required to establish the place of this technique in cervical screening. Copyright 1995, 1999 Academic Press

To test the hypothesis that insulin resistance of the spontaneously hypertensive rat (SHR) and adrenocorticotropin-hypertensive rat is related to a difference in the proportion of the functionally different, alternatively spliced exon 11 isoforms of the insulin receptor.

Exposure of primary cultures of embryonic rat striatal neurons to agents releasing nitric oxide (NO), including sin-1molsidomine, S-nitroso-n-acetyl-penicillamine (SNAP), and S-nitrosoglutathione, resulted in an increase in the levels of expression of the immediate early genes c-fosand zif/268in the cultured neurons. The membrane-permeable cGMP analogue, 8-bromo-cGMP, did not significantly affect c-fosand zif/268mRNA levels, and the highly selective inhibitor of cGMP-dependent protein kinase, KT5823, was unable to inhibit the elevation in c-fosand zif/268mRNA levels induced by SNAP. The induction of c-fosby the calcium ionophore A23187 was reduced by treatment with SNAP or 8-bromo-cGMP. Inhibitors of ADP-ribosyltransferases attenuated the stimulation of c-fosexpression by SNAP. These results demonstrate for the first time that NO can induce immediate early gene expression in neurons, suggesting that NO may act as a mediator of neuronal plasticity via alterations in the expression of downstream genes. In addition, the results suggest that NO may exert these effects through a pathway that does not involve guanylate cyclase and cGMP-dependent protein kinase.

1. Recent molecular genetic studies have implicated the low-density-lipoprotein receptor gene locus (LDLR, at chromosome 19p13.2) in obesity in essential hypertensive patients and in the atherogenic lipoprotein phenotype. The present study examined genotypes for the obesity-associated ApaLI restriction fragment length polymorphism of LDLR, and genotypes for a hypertension-associated RsaI restriction fragment length polymorphism at the insulin receptor gene (INSR) locus, which is linked to LDLR, in relation to plasma lipids, body mass index and blood pressure in 27 obese and 57 non-obese Caucasians with severe essential hypertension, selected on the basis of having parents who were both hypertensive, and in 25 obese and 45 non-obese normotensive subjects selected on the basis of having parents who were both normotensive after the age of 50 years. 2. Plasma triacylglycerol and low-density-lipoprotein-cholesterol were elevated in hypertensive patients, but did not differ between the obese and non-obese hypertensive groups. Significant positive correlations were seen between body mass index and triacylglycerol and low-density-lipoprotein-cholesterol in the obese and non-obese hypertensive patients, respectively. In addition, obese hypertensive patients had significantly higher diastolic blood pressure than non-obese hypertensive patients. 3. The eight obese hypertensive patients who were homozygous for the obesity-associated 6.6 kb allele of the ApaLI restriction fragment length polymorphism of LDLR (‘6.6.kb homozygotes’) had a significantly higher body mass index [34 ± 6.0 (SD) kg/m2] than the 18 heterozygotes (29 ± 2.7 kg/m2) and the single subject who was homozygous for the 9.4 kb allele (29 kg/m2) (P = 0.012 by one-way analysis of variance). The body mass index of the eight hypertensive 6.6 kb homozygotes was also greater than the body mass index of 29 ± 2.4 kg/m2 observed for the eight obese normotensive 6.6 kb homozygotes. In addition, the eight obese hypertensive 6.6 kb homozygotes had a higher plasma triacylglycerol [4.2 ± 0.77 (SEM) mmol/l] than the 18 obese hypertensive heterozygotes (2.4 ± 0.33 mmol/l; P = 0.045). Non-obese hypertensive patients showed no significant gentotypic differences in relation to the LDLR restriction fragment length polymorphism. 4. In the normotensive group, however, the frequency of the 6.6 kb allele of the LDLR ApaLI restriction fragment length polymorphism in obese subjects (0.54) was not significantly greater than in non-obese subjects (0.48) [cf. the significantly (P = 0.004) different values of 0.63 and 0.39, respectively, in obese and non-obese hypertensive patients]. Moreover, the LDLR genotype showed no significant relationship to the body mass index or plasma lipids in the obese and non-obese normotensive groups. 5. In the case of genotypes for the INSR restriction fragment length polymorphism, the only difference was slightly higher total and low-density-lipoprotein-cholesterol in non-obese hypertensive patients who possessed the hypertension-associated 7.0 kb allele. 6. Comparison of combined genotypes for LDLR and INSR restriction fragment length polymorphisms in hypertensive patients indicated that each associated independently in the various groups. 7. In conclusion, the present study has found that in obese hypertensive patients a LDLR variant is associated with higher body mass index and plasma triacylglycerol, although a causal relationship of LDLR in obesity and hyperlipidaemia in such patients remains to be established.

INDUCTION of long-term potentiation (LTP) in the hippocampus is associated with changes in expression of a variety of different proteins and is thought to be the mechanism which underlies synaptic plasticity. The 25 kDa synaptosomal-associated protein (SNAP-25) is a presynaptic protein which is involved in neurotransmitter exocytosis at the nerve terminal. Two isoforms of SNAP-25 have so far been identified (a and b) which differ in their distribution and developmental regulation. Using in situhybridization, we demonstrated that the mRNA levels of the two isoforms of this protein are increased 2 h after the induction of LTP in granule cells of the dentate gyrus following high frequency stimulation of the perforant path in vivo. These observations further demonstrate the involvement of both isoforms of SNAP-25 in functional synaptic plasticity, although their exact roles have yet to be fully determined.

We examined the DNA sequence and transcription factor requirements for cAMP-induced transactivation of the human renin promoter using Calu-6 cells that express human renin mRNA endogenously. A series of constructs containing 896 base pairs of human renin 5′-flanking DNA fused to the luciferase gene and containing either the native, a consensus, or a nonfunctional cAMP response element (CRE) were used to assess DNA sequence requirements mediating the cAMP response. Expression vectors encoding the CREB-1 transcription factor, a dominant negative mutant form of CREB-1, and the catalytic subunit of protein kinase A (PKA) were used to assess transcription factor requirements mediating the cAMP response. Forskolin treatment alone only caused a 2-3-fold activation of the HRENpromoter in Calu-6 cells, but nearly a 10-fold activation in JEG-3 cells, which do not express renin but are highly responsive to cAMP. Gel shift assays revealed the binding of five specific DNA-protein complexes consisting of the ATF-1 and CREB-1 transcription factors, one of which was an ATF-1·;CREB-1 heterodimer suggesting the potential for regulation of CREB-1 activity by ATF-1. However, over-expression of CREB-1 did not significantly enhance forskolin-induced human renin transcriptional activity. Transfection of both Calu-6 and JEG-3 cells with a PKA expression vector resulted in a 10-fold induction of human renin transcriptional activity in constructs containing the native or consensus CRE and 5-fold activation in a construct containing a nonfunctional CRE. We confirmed that the PKA response has both a CREB-dependent and CREB-independent component by demonstrating that the PKA response was abolished by co-transfection of a dominant negative mutant form of CREB-1 into cells containing the native or consensus CRE construct but not in cells containing the nonfunctional CRE construct. We therefore conclude that the human renin promoter can be transcriptionally activated in a renin expressing cell line through the cAMP-PKA pathway and is mediated by both a CREB-dependent and CREB-independent mechanism.

1. The oral administration of 2·5 mg of the dopamine (3,4-dihydroxyphenethylamine) agonist bromoergocriptine enhanced the osmotically stimulated rise in plasma [arginine]vasopressin ([Arg]VP) concentrations in five normal human subjects. 2. This finding lends support to the suggestion that the osmotically induced release of [Arg]VP is under dopaminergic control in man.

Essential hypertension is a highly hereditable disorder in which genetic influences predominate over environmental factors. The molecular genetic profiles which predispose to essential hypertension are not known. In rats with genetic hypertension, there is some recent evidence pointing to linkage of renin gene alleles with blood pressure. The genes for renin and antithrombin III belong to a conserved synteny group which, in humans, spans the q21.3-32.3 region of chromosome I and, in rats, is linkage group X on chromosome 13. The present study examined the association of particular human renin gene (REN) and antithrombin III gene (A73) polymorphisms with essential hypertension by comparing the frequency of specific alleles for each of these genes in 50 hypertensive offspring of hypertensive parents and 91 normotensive offspring of normotensive parents. In addition, linkage relationships were examined in hypertensive pedigrees with multiple affected individuals. Alleles of a REN H/ndlll restriction fragment length polymorphism (RFLP) were detected using a genomic clone, l HR5, to probe Southern blots of H/ndlll-cut leucocyte DNA, and those for an AT3 Psti RFLP were detected by phATIII 113 complementary DNA probe. The frequencies of each REN allele in the hypertensive group were 0.76 and 0.24 compared with 0.74 and 0.26 in the normotensive group. For AT3, hypertensive allele frequencies were 0.49 and 0.51 compared with normotensive values of 0.54 and 0.46. These differences were not significant by χ2analysis (P>0.2). Linkage analysis of a family (data from 16 family members, 10 of whom were hypertensive), informative for both markers, without an age-of-onset correction, and assuming dominant inheritance of hypertension, complete penetrance and a disease frequency of 20 did not indicate linkage of REN with hypertension, but gave a positive, although not significant, logarithm of the odds for linkage score of 0.784 at a recombination fraction of 0 for AT3 linkage to hypertension. In conclusion, the present study could find no evidence for an association of a REN H/ndlll RFLP with essential hypertension or for a linkage of the locus defined by this RFLP in a family segregating for hypertension. In the case of an AT3 Psti RFLP, although association analysis was negative, linkage analysis suggested possible involvement (odds of 6 1 in favour) of a gene located near the 1q23 locus with hypertension in one informative family.

Genes for the small human glandular kallikrein gene family were isolated. Members of this family include renal/pancreatic kallikrein, prostate-specific antigen and a kallikrein encoded by the first gene that was isolated and completely sequenced, hGK-1. All share strong nucleotide sequence homology, although hGK-1 and the prostate-specific antigen gene are more closely related (86 identity in coding nucleotides). Renal/pancreatic kallikrein has 77 nucleotide homology to prostate-specific antigen, but only 60 amino acid homology. There is strong homology in the 5'-flanking DNA with mouse kallikrein genes, suggesting common regulatory mechanisms. In the rat one-kidney, one clip model of hypertension, renal kallikrein messenger (m) RNA increased during the initial transient rise in plasma renin, and then decreased.

To determine whether a microsatellite polymorphism of the insulin receptor gene (INSR) is associated with essential hypertension, as has been demonstrated previously for an Rsalrestriction fragment length polymorphism (RFLP), and to examine blood pressure and plasma lipid profiles in relation to genotype.

1. There is evidence to suggest that essential hypertension is a polygenic disorder and that it arises from yet-to-be-identified predisposing variants of certain genes that influence blood pressure. The cloning of various hormone, enzyme, adrenoceptor and hormone receptor genes whose products are involved in blood pressure control and the identification of polymorphisms of these has permitted us to test their genetic association with hypertension. 2. Cross-sectional analyses of a number of candidate gene markers were performed in hypertensive and normotensive subjects who were selected on the basis of both parents being either hypertensive or normotensive, respectively, and the difference in total alleles on all chromosomes for each polymorphism between the hypertensive and normotensive groups was tested by χ2 analysis with one degree of freedom. 3. A marked association was observed between hypertension and insertion alleles of polymorphisms of the insulin receptor gene (INSR) (P <0.0040) and the dipeptidyl carboxypeptidase-1 (angiotensin I-converting enzyme; kininase II) gene (DCP1) (P <0.0018). No association with hypertension was evident, however, for polymorphisms of the growth hormone, low-density lipoprotein receptor, renal kalli-krein, α2- and β1-adrenoreceptor, atrial natriuretic factor and insulin genes. 4. All but one of the hypertensive subjects had at least one of the hypertension-associated alleles, and although subjects homozygous for both were three times more frequent in the hypertensive group, examination of the nine possible genotypes suggested that the INSR and DCP1 alleles are independent markers for hypertension. 5. The present results suggest that genetic variant(s) in close linkage disequilibrium with polymorphisms at INSR and DCP1 may be involved in part in the aetiology of essential hypertension.

The aim of the present study was to use a highly sensitive, polymerase chain reaction (PCR) technique to examine the controversial question of renin gene expression in the heart and to determine whether expression in cardiac tissue can be stimulated.

We have examined the effect of removal of the submandibular gland on one-kidney, one clip (1K1C) hypertension in the rat. Five weeks after application of a silver clip with a 0.20-mm gap, 15 hypertensive rats were sialoadenectomized. This was followed by a decrease in systolic blood pressure (SBP) within 1 day by 22 ± 4 mmHg (±s.e.m.) and in nine rats pressure stabilized within 1 week at 133 ± 5 (cf. 166 ± 2 before sialoadenectomy). In the other six rats the initial hypotensive response was followed by a gradual return to hypertensive levels, reaching 178 ± 4 mmHg 6 weeks later. Sham-sialoadenectomized rats remained hypertensive throughout. When a 0.15-mm gap clip was used in a similar experiment rats became hypertensive after 2 weeks, and sialoadenectomy lowered SBP to normal in half of them, after which pressure tended to return to hypertensive levels in most. No change in SBP was found in sham-operated hypertensive rats. Sialoadenectomy performed at the time of clipping with a 0.15-mm gap clip and unilateral nephrectomy delayed the development of hypertension. Systolic pressure then fell from 153 ± 14 at 4 weeks to 105 ± 8 at 12 weeks after operation in five rats, but continued to increase in eight rats from 148 ± 10 at 4 weeks to 172 ± 15 at 12 weeks. These experiments thus demonstrate that the submandibular gland may contribute to the onset and maintenance of one-kidney, one clip hypertension in the rat, particularly in less severe stenosis.

This two-part review aims to consolidate information on renin structure, synthesis, precursor processing, intracellular shunting and transcriptional control. Such revolutionary advances in the molecular knowledge of renin stem from the cloning of mouse renin complementary DNA in the early 1980s.

This review addresses the question of renin gene control by examining information from messenger RNA, transgene, transient expression and DNA-protein binding studies.

Chromosome 16p11.2 duplications dramatically increase risk for schizophrenia, but the mechanisms remain largely unknown. Here, we show that mice with an equivalent genetic mutation (16p11.2 duplication mice) exhibit impaired hippocampal-orbitofrontal and hippocampal-amygdala functional connectivity. Expression of schizophrenia-relevant GABAergic cell markers (parvalbumin and calbindin) is selectively decreased in orbitofrontal cortex, while somatostatin expression is decreased in lateral amygdala. When 16p11.2 duplication mice are tested in cognitive tasks dependent on hippocampal-orbitofrontal connectivity, performance is impaired in an 8-arm maze “N-back” working memory task and in a touchscreen continuous performance task. Consistent with hippocampal-amygdala dysconnectivity, deficits in ethologically relevant social behaviors are also observed. Overall, the cellular/molecular, brain network, and behavioral alterations markedly mirror those observed in schizophrenia patients. Moreover, the data suggest that 16p11.2 duplications selectively impact hippocampal-amygdaloid-orbitofrontal circuitry, supporting emerging ideas that dysfunction in this network is a core element of schizophrenia and defining a neural circuit endophenotype for the disease.