DHEA and response to antidepressant treatment: A Mendelian Randomization analysis

Treatment response is hard to predict and detailed mechanisms unknown. Lower levels of the dehydroepiandrosterone sulphate (DHEA(S)) - a precursor to testosterone and estrogen - have been associated to depression and to response to antidepressant treatment. Previous studies however may have been ridden by confounding and reverse causation. The aim of this study is to evaluate whether higher levels of DHEA(S) are causally linked to response to antidepressants using mendelian randomization (MR). We performed a Two-sample MR analysis using data the largest publicly available GWAS of DHEA(S) levels (n = 14,846) using eight common genetic variants associated to DHEA(S) (seven single nucleotide polymorphisms and one variant rs2497306) and the largest GWAS of antidepressant response (n = 5218) using various MR methods (IVW, MR Egger, Weighted mean, weighted mode, MR-PRESSO) and single SNP analysis. We further investigated for pleiotropy conducting a look up on PhenoScanner and GWAS Catalog. Results show no evidence for DHEA(S) gene risk score from any of MR methods, however, we found a significant association on individual variant analysis for rs11761538, rs17277546, and rs2497306. There was some evidence for heterogeneity and pleiotropy. This is the first paper to show some evidence for a causal association of genetically-predicted DHEA and improvement of depressive symptoms. The effect is not a simple linear effect, and we were unable to dissect whether the effect was direct effect of DHEA(S), mediated by DHEA(S) or on the pathway is not yet clear. Further studies using more refined instrumental variables will help clarify this association.

Low-grade inflammation predicts persistence of depressive symptoms

RATIONALE

Evidence suggests that depression is cross-sectionally and longitudinally associated with activation of inflammatory response system. A few studies, however, have investigated the longitudinal relationship between raised inflammatory biomarkers and persistence of depressive symptoms. We examined the temporal relationship between serum levels of inflammatory biomarkers and persistence of depressive symptoms among older participants.

METHODS

Center for Epidemiologic Studies Depression Scale (CES-D) was used to assess depressive symptoms at baseline and at 5-year follow-up in 656 participants (233 men, 423 women) aged >60 years of the Rotterdam Study. Markers of inflammation interleukin (IL)-6, alpha-1-antichymotrypsin (ACT) and C-reactive protein (CRP) were assessed at baseline, and all participants taking antidepressant medications were excluded from the analysis.

RESULTS

No cross-sectional association was found between IL-6, ACT and CRP with depressive symptoms at baseline. However, higher levels of IL-6 and CRP predicted depressive symptoms at 5-year follow-up. Adjustment for confounding variables had no impact on the observed associations. Similarly, a positive association was found between baseline levels of IL-6 (OR = 2.44, p = 0.030) and CRP (OR = 1.81, p = 0.052) and persistence of depressive symptoms over 5 years.

CONCLUSION

Our data suggest that dysregulation of the inflammatory response system is associated with a more severe form of depression more likely to re-occur.

Socio-demographic characteristics, lifestyle factors and burden of morbidity associated with self-reported hearing and vision impairments in older British community-dwelling men: a cross-sectional study

BACKGROUND

Hearing and vision problems are common in older adults. We investigated the association of self-reported sensory impairment with lifestyle factors, chronic conditions, physical functioning, quality of life and social interaction.

METHODS

A population-based cross-sectional study of participants of the British Regional Heart Study aged 63-85 years.

RESULTS

A total of 3981 men (82% response rate) provided data. Twenty-seven per cent (n = 1074) reported hearing impairment including being able to hear with aid (n = 482), being unable to hear (no aid) (n = 424) and being unable to hear despite aid (n = 168). Three per cent (n = 124) reported vision impairment. Not being able to hear, irrespective of use of hearing aid, was associated with poor quality of life, poor social interaction and poor physical functioning. Men who could not hear despite hearing aid were more likely to report coronary heart disease (CHD) [age-adjusted odds ratios (ORs) 1.89 (95% confidence interval 1.36-2.63)]. Vision impairment was associated with symptoms of CHD including breathlessness [OR 2.06 (1.38-3.06)] and chest pain [OR 1.58 (1.07-2.35)]. Vision impairment was also associated with poor quality of life, poor social interaction and poor physical functioning.

CONCLUSIONS

Sensory impairment is associated with poor physical functioning, poor health and poor social interaction in older men. Further research is warranted on pathways underlying these associations.

Inflammatory activation is associated with a reduced glucocorticoid receptor alpha/beta expression ratio in monocytes of inpatients with melancholic major depressive disorder

In this study, we used new technology to investigate whether a coherent pattern of enhanced expression of inflammatory and other immune activation genes in circulating monocytes is found in patients with major depression. Since a high inflammatory state of monocytes might be related to glucocorticoid resistance, we also included the genes for the two isoforms of the glucocorticoid receptor. For this study, we aimed at finding a similar coherent pattern of inflammatory and immune activation genes in monocytes of patients with MDD and recruited 47 medication-free melancholic MDD inpatients and 42 healthy controls. A quantitative-polymerase chain reaction (Q-PCR) monocyte gene expression analysis was performed using a panel of inflammatory-related genes previously identified as abnormally regulated in mood disorder patients. Selected serum cytokines/chemokines were assessed using a cytometric bead array. Depressive symptoms were analysed using Hamilton depression scores (HAMD). Thirty-four of the 47 monocyte inflammatory-related genes were significantly upregulated and 2 were significantly downregulated as compared to controls, the latter including the gene for the active GRα in particular in those with a high HAMD score. The reduced GRα expression correlated strongly to the upregulation of the inflammatory genes in monocytes. Serum levels of IL6, IL8, CCL2 and VEGF were significantly increased in patients compared to controls. Our data show the deregulation of two interrelated homoeostatic systems, that is, the immune system and the glucocorticoid system, co-occurring in major depression.

Attraction of female mediterranean fruit flies to the five major components of male-produced pheromone in a laboratory flight tunnel

Attraction and pheromonal activity of five major identified components of the male-produced sex pheromone of the Mediterranean fruit flyCeratitis capitata to virgin laboratory-reared females was assessed in a laboratory flight tunnel. Dual-choice competitive assays were run to establish a baseline response of virgin females to live male pheromone, individual components, and an ensemble of all five compounds alone (air control) and competitively against one another. Approximately 50% of the females released in the tunnel were captured on leaf models emitting pheromonal odors from five live males. Over 37% of released females responded to an ensemble of five major identified components presented in individual capillaries. Response of females to individual components was less than 10%. Competitive assays showed the live male-produced pheromone to be more attractive than either the five major component ensemble (FMCE) or individual components. Further research is likely to identify other male-produced compounds with pheromonal activity that could improve development of a pheromone-based trap for monitoring Mediterranean fruit fly populations.

Lack of clinical therapeutic benefit of antidepressants is associated overall activation of the inflammatory system

Despite the evidence of an association between depression and increased inflammatory markers, still little is known in relation to the most severe cases of the disorder i.e., those who fail to respond to antidepressants. We have assessed the cytokine profile and cortisol levels in 21 healthy controls (HC) and 19 medicated patients with depression with treatment-resistance (TRD) moderately ill. As an initial exploratory analysis, we have also related cytokine profile to the patient's clinical treatment outcome after an inpatient admission. Cytokine profile was measured in the serum by the Cytokine Array I kit (Randox). Plasma cortisol was carried out using a commercially available for the IMMULITE system. When compared to healthy controls, depressed patients had higher levels of cortisol, IL-6, IL-10, but lower levels of IL-4 and VEGF. Our exploratory analysis showed subjects who did not go on to respond to the inpatient admission treatment package had lower levels of MCP-1, and a trend toward lower levels of VEGF. Taking together, these data suggest that lack of clinical therapeutic benefit of antidepressants is associated with overall activation of the inflammatory system.

Distinct types of tumors exhibit differential grade of inflammation and angiogenesis in mice

Inflammation, angiogenesis and cytokine production are common features of almost, if not all tumors. However, the extent of these processes induced by different types of tumors has not been evaluated. We investigated the growth pattern of the experimental metastatic tumors, B16F10 melanoma, CT26.WT colon and 4T1 mammary cells inoculated in the flank of syngeneic mice and determined the degree of inflammation, angiogenesis, and production level of pro-inflammatory and pro-angiogenic cytokines within the tumors. In addition, we have analyzed vascular changes in the interface between the tumors and the adjacent cutaneous tissue and levels of relevant pro-inflammatory and pro-angiogenic cytokines systemically. The weight of tumors 15 days post-inoculation of 10(6) cells was markedly different. Melanomas were 2 and 10-fold heavier than colon and mammary tumors, respectively. Locally, CT26.WT tumor cells induced more vessels in cutaneous tissue adjacent to the tumors but systemically, the plasma levels of VEGF were higher (approximately 2-fold) in 4T1 tumor-bearing mice compared with the other two tumors. Mammary tumors presented the most prominent inflammatory content as assessed by a range of markers (inflammatory enzymes and cytokines). The vascular index, as determined by the intra-tumor amount of hemoglobin and number of vessels in hot spot areas, was also higher (approximately 2-fold) in melanomas compared with the other two tumors. These findings showing that distinct tumor types determine differential grade of inflammation, angiogenesis and host interaction in mice may provide new insights to tailor differential therapeutic approach based on the status of tumor biomarkers.

Antidepressants increase human hippocampal neurogenesis by activating the glucocorticoid receptor

Antidepressants increase adult hippocampal neurogenesis in animal models, but the underlying molecular mechanisms are unknown. In this study, we used human hippocampal progenitor cells to investigate the molecular pathways involved in the antidepressant-induced modulation of neurogenesis. Because our previous studies have shown that antidepressants regulate glucocorticoid receptor (GR) function, we specifically tested whether the GR may be involved in the effects of these drugs on neurogenesis. We found that treatment (for 3-10 days) with the antidepressant, sertraline, increased neuronal differentiation via a GR-dependent mechanism. Specifically, sertraline increased both immature, doublecortin (Dcx)-positive neuroblasts (+16%) and mature, microtubulin-associated protein-2 (MAP2)-positive neurons (+26%). This effect was abolished by the GR-antagonist, RU486. Interestingly, progenitor cell proliferation, as investigated by 5'-bromodeoxyuridine (BrdU) incorporation, was only increased when cells were co-treated with sertraline and the GR-agonist, dexamethasone, (+14%) an effect which was also abolished by RU486. Furthermore, the phosphodiesterase type 4 (PDE4)-inhibitor, rolipram, enhanced the effects of sertraline, whereas the protein kinase A (PKA)-inhibitor, H89, suppressed the effects of sertraline. Indeed, sertraline increased GR transactivation, modified GR phosphorylation and increased expression of the GR-regulated cyclin-dependent kinase-2 (CDK2) inhibitors, p27(Kip1) and p57(Kip2). In conclusion, our data suggest that the antidepressant, sertraline, increases human hippocampal neurogenesis via a GR-dependent mechanism that requires PKA signaling, GR phosphorylation and activation of a specific set of genes. Our data point toward an important role for the GR in the antidepressant-induced modulation of neurogenesis in humans.

Acute increase in urinary 6-sulfatoximelatonin after clomipramine, as a predictive measure for emotional improvement

Nocturnal melatonin pineal output is triggered by sympathetic outflow. Antidepressants that block norepinephrine neuronal uptake should increase pineal function. This can be monitored by measuring 6-sulfatoximelatonin (aMT6s), the main melatonin metabolite, in the urine. In this study, we compared the excretion of aMT6s before (baseline), one, and 21 days after administration of clomipramine to healthy subjects (n = 32). At the end of treatment, subjects were divided into responders (n = 12) and non-responders (n = 20) according to the improvement in their emotional state in three out of four domains (interpersonal tolerance, efficiency, well-being and feeling different from the usual self). There was no difference in aMT6s before clomipramine between responders and non-responders in any of the time intervals analysed (06:00-12:00, 12:00-18:00, 18:00-24:00 and 24:00-06:00 hours). At day one, but not at day 21, the fraction of aMT6s excreted during the time interval 24:00-06:00, relative to the total amount excreted by each subject per day, was significantly higher (P = 0.0287) than baseline (0.57 +/- 0.04) in responders. No significant difference was observed in non-responders. The increase in pineal function induced by clomipramine was restricted to day one, indicating that long-lasting adaptation restores pineal function. In addition, the day one increase in aMT6s was significantly increased only in the responders group, raising the possibility that the blocking of neuronal uptake is predictive of emotional improvement.

Antidepressants, but not antipsychotics, modulate GR function in human whole blood: an insight into molecular mechanisms

Clinical studies have demonstrated an impairment of glucocorticoid receptor (GR)-mediated negative feedback on the hypothalamic-pituitary-adrenal (HPA) axis in patients with major depression (GR resistance), and its resolution by antidepressant treatment. Recently, we showed that this impairment is indeed due to a dysfunction of GR in depressed patients (Carvalho et al., 2009), and that the ability of the antidepressant clomipramine to decrease GR function in peripheral blood cells is impaired in patients with major depression who are clinically resistant to treatment (Carvalho et al. 2008). To further investigate the effect of antidepressants on GR function in humans, we have compared the effect of the antidepressants clomipramine, amytriptiline, sertraline, paroxetine and venlafaxine, and of the antipsychotics, haloperidol and risperidone, on GR function in peripheral blood cells from healthy volunteers (n=33). GR function was measured by glucocorticoid inhibition of lypopolysaccharide (LPS)-stimulated interleukin-6 (IL-6) levels. Compared to vehicle-treated cells, all antidepressants inhibited dexamethasone (DEX, 10-100nM) inhibition of LPS-stimulated IL-6 levels (p values ranging from 0.007 to 0.1). This effect was specific to antidepressants, as antipsychotics had no effect on DEX-inhibition of LPS-stimulated IL-6 levels. The phosphodiesterase (PDE) type 4 inhibitor, rolipram, potentiated the effect of antidepressants on GR function, while the GR antagonist, RU-486, inhibited the effect of antidepressants on GR function. These findings indicate that the effect of antidepressants on GR function are specific for this class of psychotropic drugs, and involve second messenger pathways relevant to GR function and inflammation. Furthermore, it also points towards a possible mechanism by which one maybe able to overcome treatment-resistant depression. Research in this field will lead to new insights into the pathophysiology and treatment of affective disorders.

Can ménage-a-trois be used for controlling insects?

We propose a new cross-species disruption approach that might be capable of interrupting mating of one species that uses another insect species as the mercenary agent. We argue that insects treated with a sufficiently powerful attractant for a second species might interfere with mating of one or both species, for example, by leading males astray in pursuit of the false trails created by suitably dosing individuals of the first species. Our reciprocal test systems used (1) methyl eugenol, an attractant for male oriental fruit flies (Bactrocera dorsalis), applied to melon flies (B. cucurbitae) and (2) cuelure, a lure for male melon flies, applied to B. dorsalis. There was no mortality 1 week after either attractant was applied to individual flies at doses up to 100 ng, which was effective in attracting insects in a field cage and in the field. In wind tunnel choice tests, 100 ng of either lure topically applied to tethered flies attracted fruit fly males of the second species, which exhibited prolonged bouts of physically disruptive behaviors including chasing and bumping. In small cages, treatment of males did not reduce mating of either species, with one group of three (ménage) per cage. However, in large field cages with multiple pairs of both species present, there was a significant reduction in the mating of melon flies resulting from methyl eugenol applied to males compared to untreated controls. The treatment of oriental fruit flies with cuelure also reduced their mating to a lesser extent. These results do not yet provide the practical proof of this new concept for pest management, but other model systems may be more appropriate. This work is novel in presenting attractants on a moving target, in this case, another insect species.

Field attraction of Mediterranean fruit fly, Ceratitis capitata (Wiedemann) to synthetic stereoselective enantiomers of the ceralure B1 isomer

Stereoselectively synthesized enantiomers of ethyl cis-5-iodotrans-2-methylcyclohexane-1-carboxylate (ceralure B1), a potent lure for male Mediterranean fruit flies, were tested in the laboratory and the field against laboratory reared sterile flies. The (-)-ceralure B1 enantiomer was significantly more attractive than the (+)-ceralure B1 antipode. Dose-response studies of the above compounds demonstrated that (-)-ceralure B1 and to a lesser extent, racemic ceralure B1, captured consistently more male flies than trimedlure, the current male attractant used in detection programs. Longevity tests demonstrated that, over a three-week period, both (-)-ceralure B1 and racemic ceralure B1 caught significantly more flies than trimedlure. The synthesis of specific enantiomers of ceralure B1 shows great promise as a male attractant that could replace trimedlure for detection and delimitation in action programs aimed at this exotic pest.

Thoracoscopic enucleation of a leiomyoma of the upper thoracic esophagus

The authors present two cases of leiomyoma of the upper esophagus. Both of the cases presented with dysphagia, and one patient complained of pyrosis. An upper gastrointestinal endoscopy showed midesophageal narrowing without mucosal irregularity, suggestive of leiomyoma. The patients were successfully treated by thoracoscopic enucleation of the leiomyoma, using four thoracic trocars. In one patient (Case 1), the azygus vein had to be divided. Both of the patients are asymptomatic in the late-postoperative period.

Efficacy of a long-acting formulation of ivermectin against Psoroptes ovis (Hering, 1838) on cattle

A study was conducted in cattle experimentally infested with Psoroptes ovis to compare the prophylactic control against P. ovis provided by a long-acting injectable formulation of ivermectin to that of a commercially available injectable formulation of doramectin. Thirty Holstein steers were used. Animals were allocated by restricted randomization based on Day 0 body weight, forming six replicates of five animals each. Within each replicate, one animal was randomly allocated to one of the following treatment groups, with ivermectin and doramectin administered subcutaneously where indicated: (1) untreated controls; (2) ivermectin long-acting injectable (LAI) 630 mcg/kg, 56 days before challenge; (3) ivermectin LAI 630 mcg/kg, 42 days before challenge; (4) ivermectin LAI 630 mcg/kg, 35 days before challenge; or (5) doramectin 200 mcg/kg, 35 days before challenge. Animals were housed in individual pens 1 week prior to treatment. All animals were experimentally infested with P. ovis mites in the area between the shoulders, on the same day. Live mites were counted in scrapings from mange lesions at 2 sites on each animal 14, 21 and 28 days after challenge. Live mites were found in 33, 67 and 83% of the untreated controls on each respective evaluation. No P. ovis mites were found in steers treated with ivermectin LAI. Those animals showed lower (P < 0.05) mite counts than untreated controls on evaluations conducted 21 and 28 days after challenge. These results indicate that the ivermectin long-acting injectable formulation prevents induced infestations by P. ovis for at least 56 days after treatment. Doramectin injectable formulation, used at 200 mcg/kg, did not have a prophylactic effect 35 days after treatment.

A comparison of molar root canal preparation using stainless-steel and nickel-titanium instruments

Fifty-four extracted human mandibular molars were embedded and sectioned at two levels. The reassembled mesial root canals were prepared with stainless-steel hand K-files (Flexofiles) and either Nitiflex or Mity nickel-titanium hand K-files using a push-pull anticurvature filing technique. Each of the three experimental groups contained 36 mesial canals randomly distributed. Superimposed pre- and post-instrumentation cross-sectional root images were magnified using a stereomicroscope and transferred to a computer for measurement and statistical analysis. The direction and extent of canal center movement were evaluated. At the apical level, the groups produced no significant difference of direction of canal center movement. In cervical sections, all groups tended to move in a distolingual direction. The three groups, however, produced no significant difference in the cervical sections in the extent of canal center movement. In apical sections, Nitiflex produced the least canal center movement.

A review of the use of a controlled-release formulation of ivermectin in the treatment and prophylaxis of Psoroptes ovis infestations in sheep

The options for the treatment and control of sheep scab (psoroptic mange) have been increased in recent years through the introduction of the endectocides ivermectin, doramectin and moxidectin. Whilst therapeutic efficacy is good, the current injectable formulations offer limited protection against re-infestation with Psoroptes ovis. An intraruminal controlled-release formulation of ivermectin has been developed to provide therapeutic and prophylactic activity against a range of sensitive endo- and ecto-parasites of sheep for 100 days after administration. These ivermectin boluses are designed to release ivermectin at 20-40 microg/kg/day over 100 days and were developed for use in sheep of 20-90 kg bodyweight. Several controlled therapeutic and prophylactic trials against sheep scab have been conducted under a variety of protocols with such boluses in Europe and South America. The results of these studies indicate that the bolus provides 100% therapeutic efficacy against established P. ovis infestations and equivalent prophylactic efficacy against challenge infestations administered during the active life of the bolus.

Efficacy of ivermectin in a controlled release formulation against Psoroptes ovis (Hering, 1838) gervais, 1841 (Acari: Psoroptidae) on sheep

Three trials including 42 sheep were conducted in Brazil or Germany to evaluate the therapeutic (two trials) and prophylactic (one trial) efficacy of an ivermectin controlled release capsule (CRC) against Psoroptes ovis infestation. In one therapeutic trial naturally infested sheep were used while in the other trials infestations were experimentally induced. In each trial half of the animals were treated on Day 0 with one ivermectin controlled release capsule that delivers ivermectin at a rate of 1.6 mg/day for approximately 100 days, that is 20 mcg/kg/day to a 80 kg animal, while the other half remained untreated. In both therapeutic trials mites were counted in skin scrapings and their presence was recorded at predilection sites one day before treatment and at weekly intervals from Day 7 to Day 56. In the trial conducted to evaluate the prophylactic efficacy the sheep were experimentally infested with P. ovis 21 and 28 days post-treatment and mites were counted and recorded at predilection sites on Days 42, 49 and 56. The ivermectin controlled release capsule was completely effective in eliminating the P. ovis mites within 28 days of administration and it prevented the establishment of an infestation of P. ovis induced 21 and 28 days after administration.

[Supravalvular aortic stenosis in two black patients]

Two male black patients, 18 and 12-year-old, with mental retardation and typical elfin face, presented with severe supravalvular aortic stenosis, thus characterizing Williams's or aortic supravalvular stenosis syndrome. Both were submitted to surgical treatment of the stenosis, and are asymptomatic after a one and four years follow-up. For the first time this syndrome, in its classical form, is described in black patients.

Chromosome abnormalities in selected newborn infants with malformations in Brazil

Between 1982 and 1985, 109 infants were referred for cytogenetic examination out of a population of 73,192 liveborn infants from eight maternity hospitals surveyed by the ECLAMC/MONITOR program. Thirty-one of the children had a chromosome abnormality different from trisomy 21. Considering the total population surveyed, trisomy 18 was detected in 1:6,099; trisomy 13 was seen in 1:24,397 and unbalanced rearrangements were found in 1:7,319 infants. Those rates were not significantly different from the expected ones, as compared to previous cytogenetic surveys of consecutive births. We concluded that most chromosome abnormalities associated with congenital malformations can be detected at low cost, provided there is a high accuracy of clinical examination and referral criteria, as well as close cooperation between pediatricians and geneticists.

Efficacy of topically applied ivermectin against Boophilus microplus (Canestrini, 1887) in cattle

Systemic efficacy of ivermectin applied topically was evaluated against the cattle tick, Boophilus microplus. Twenty cattle with induced infestations were randomly allocated to five groups of equal size based on the numbers of engorged female ticks which fell through the slatted floor of individual pens during the 3 days prior to treatments. Control cattle were non-medicated. Cattle in three groups were given ivermectin at 200, 500 or 1000 mcg kg-1 in a topical formulation applied along the backline from the withers to the rump; cattle in the fifth group were given ivermectin in an injectable formulation subcutaneously at 200 mcg kg-1. Individual 24-h tick collections were made three times weekly for 5 weeks after treatment. Engorged female B. microplus were incubated to determine effects on reproduction. Based on the numbers of engorged female B. microplus collected following treatments, overall efficacy of ivermectin applied topically at 200, 500 and 1000 mcg kg-1 was 50, 85 and 91%, respectively, whereas ivermectin given at 200 mcg kg-1 subcutaneously was 80% effective. The index of reproduction for ivermectin given topically was reduced by 84, 94 and 95%, respectively, and that for ivermectin subcutaneously was 94%. No significant differences (P greater than 0.05) were found for these variables between ivermectin given topically at 500 or 1000 mcg kg-1 versus 200 mcg kg-1 given subcutaneously.