[Factors associated with poor blood pressure control in Moroccan hypertensive patients]

STUDY AIM

Hypertension is a major public health concern worldwide and non-controlling it can lead to various cardiovascular complications. Controlling blood pressure and reducing overall cardiovascular risk are two main goals of treatment. Thus, this study aimed to determine the proportion and factors associated with uncontrolled hypertension in hypertensive patients living in the Beni Mellal city.

PATIENTS AND METHODS

The cross-sectional survey took place between June and March 2019. It involved 580 hypertensive patients attending the primary health care facilities in Beni Mellal city, using systematic sampling.

RESULTS

A total of 580 hypertensive patients were recruited, with a mean age of 55.78 (± 10.82 years) and of which 66.89% were female. The proportion of poor blood pressure control was 74.1% and was associated in multivariate analysis with a family history of hypertension(OR = 1.60; 95% CI = [1.02-2.50]), dyslipidemia (OR = 2.05; 95% CI = [1.32 -3.20]), non-adherence to a regular BP measurement (OR = 4.13; 95% CI = [2.49 -6.86]), to treatment (OR = 3.64; 95% CI = [2.34-5.65]) and regular biological monitoring (OR = 2.45; 95% CI = [1.46-4.08]).

CONCLUSION

Despite the free and available of treatment, the proportion of uncontrolled hypertension was high. This might be linked to a lack of awareness and education concerning disease self-management.

Eating habits, lifestyle factors and body weight status among Moroccan school adolescents (12–19 years): The case of Beni Mellal city

BACKGROUND: Overweight and obesity among children and adolescents are serious public health issues worldwide. A better understanding of the relationships between obesity and lifestyle factors is necessary for effective prevention and management of obesity in youth. AIMS: This study aimed to assess the prevalence of overweight/obesity and associated factors among schoolchildren aged 12–19 years at Beni Mellal city, Morocco. METHODS: A school based cross sectional study was carried out. A total of 516 children were included in the study. The nutritional status was classified according to the reference curves of WHO (2007). Multivariable logistic regression analysis was used to identify factors associated with overweight/obesity. The association between dependent and independent variables were assessed using odds ratio with 95% confidence interval and p value < 0.05 was considered statistically significant. RESULTS: The prevalence of overweight was 12.40% and that of obesity was 5.20%. Overweight and obesity were statistically associated with gender (Odds Ratio (OR) = 10.15[95% CI 1.37–3.81], p = 0.001); skipping breakfast (OR = 9.19 [95% CI 1.42–5.17], p = 0.002) and eating cake, pastry and biscuit 1 to 3 times per week (OR = 4.14 [95% CI 1.02–3.25], p = 0.04) and 4 or more times a week (OR = 7.83 [95% CI 1.31–4.66], p = 0.005). CONCLUSIONS: This study revealed that prevalence of overweight/obesity among school-aged children in Beni Mellal city was high. Thus, promoting healthy dietary practices, particularly improving fruit and vegetable intake is essential to reduce the burden of overweight and obesity. Furthermore, it is important to strengthen nutrition education about avoiding junk food consumption and encouraging regular physical activity.

Comparison of PCR and Conventional Serological Methods for Detection of Brucella spp. in Ovine and Caprine Blood Serum

Brucellosis is an anthropozoonotic disease. Infection of livestock with Brucella is endemic in most parts of Iran. Sistan-Baluchestan is bordered on the east by the countries of Afghanistan and Pakistan. The high prevalence of brucellosis in livestock in the eastern neighboring countries results in transmission of the disease to this province. The present research aimed to determine the prevalence of brucellosis in small ruminants in the Sistan region of Iran and to compare serological and molecular tests for the detection of brucellosis. Blood samples were taken from 150 randomly selected sheep and goats, and sera were separated. All sera were analyzed by serological (Wright and 2-ME) and molecular (Polymerase Chain Reaction (PCR)) tests. Serological tests were carried out according to the instructions of the Iranian Veterinary Organization The degree of agreement between serological tests and PCR was determined by kappa value. In this study, 17 cases (11.3%) were identified as positive by the PCR method. Wright and 2-ME tests had the highest agreement with PCR in titers ≥2/80 and ≥2/40, respectively. The results of this study show that the brucellosis in sheep and goats has a greater prevalence in the Sistan region than in most other parts of Iran, and this is important in terms of public health. It is suggested that brucellosis vaccination coverage in livestock be increased in this area and that the people in Sistan region must be notified about methods for preventing brucellosis. Also, further studies to compare conventional serologic tests with the gold standard test are recommended.

Prevalence and related factors of Salmonella spp. and Salmonella Typhimurium contamination among broiler farms in Kerman province, Iran

Salmonella is one of the most important pathogens in the poultry industry that not only causes financial and economic damage, but also, some serovars of this bacterium, including the S. Typhimurium, can infect humans through poultry-to-human transmission. The purpose of this study was to investigate the prevalence of this pathogen among broiler poultry houses in the Kerman region, southeast of Iran and to identify factors which could increase the risk for Salmonella contamination in the chickens. In a cross-sectional study, 110 poultry houses were surveyed from June to October 2018. Twenty-eight variables related to the prevalence of Salmonella contamination were considered by a questionnaire template with farmers' and laborers' help. Also, the prevalence of Salmonella in poultry manure was determined based on fecal sampling, microbiological tests and polymerase chain reaction (PCR) technique. A multivariable logistic regression model was developed to measure the influence of independent variables on Salmonella contamination. Results showed that a time interval less than one month between the two breeding periods (OR = 6.530), the number of fans less than 5 in each poultry house (OR = 4.094) and the number of houses less than 4 in each farm significantly increased the probability of infection with Salmonella spp. (ORs were respectively 9.650, 29.427 and 7.140 for one, two and three houses). Also, the results of multivariable logistic regression showed that the use of a bell drinking system (OR = 4.379) and the presence of fewer than 5 fans in each poultry house (OR = 2.512) increased significantly the risk of infection with Salmonella Typhimurium.

A Study on Mycoplasma agalactiae and Chlamydophila abortus in Aborted Ovine Fetuses in Sistan and Baluchestan region, Iran

Abortion is one of the most important economic issues in sheep flocks. Chlamydophila abortus is an agent of enzootic abortions in sheep. Mycoplasma agalactiae is the main etiological agent of contagious agalactia, which can cause abortion in sheep. The aim of this study was to investigate the prevalence of M. agalactiae and C. abortus among aborted ovine fetuses in Sistan and Baluchestan, Iran. Sheep owners were asked to transfer their aborted fetuses to a nearby veterinary clinic; furthermore, they were taught biosecurity principles. A total of 78 aborted sheep fetuses were collected from all over Sistan region in the autumn of 2015 and winter of 2016. The samples were then transferred in ice to the Anatomy Laboratory of the Veterinary Faculty of Zabol University, Zabol, Iran. The spleen and abomasum contents of the fetuses were sampled under sterile and safe conditions. Polymerase chain reaction was used to detect M. agalactiae and C. abortus. The results showed that 24 (30.8%) cases were infected with M. agalactiae. However, infection with C. abortus was not detected in any fetuses. There was no statistically significant relationship between such independent variables as the location of livestock, history of abortion, fetal gender and age, age and parity of ewe, and fetal infection with M. agalactiae. The high incidence of Mycoplasma contamination in this study may be due to inappropriate biosecurity measures and lack of vaccination against agalactia in sheep herds in Sistan region.

Anthropometric status and body image perception among Moroccan university students

BACKGROUND

University students aged between 18 and 25 undergo several physical changes as a result of transition from adolescence to adulthood. Students do not always accept those changes and sometimes develop dissatisfaction towards their figures. In such cases, it is still not clear how actual body weight status can be affected by socio-cultural factors such as body image perception. The objective of this study was to determine the link between anthropometric status and body image perception among university students.

METHODS

Two hundred and forty six (246) university students from the Faculty of Sciences and Technologies within the Beni Mellal-Khenifra region in Morocco, aged 20-24 years were interviewed using face-to-face questionnaires. Anthropometric measurements and Body Mass Index were collected. Body image perception was assessed by Figure Rating Scale, and body size dissatisfaction was calculated as Feel minus Ideal Discrepancy (FID). Data were described using means and proportions. The Student t-test and the chi-square test have been used to assess the statistical significance of group differences.

RESULTS

Underweight students represented 16.7% of the investigated sample, while 11.4% suffered from overweight and obesity, higher in females students (14.4%) than in males (7.9%). Regarding body image perception, 43.9% of participants considered themselves underweight; whereas only 4.2% considered themselves overweight with no significant differences related to gender. Of note, the total prevalence of body image dissatisfaction was around 69.8%. Finally, among overweight/obese students, 88.9% of females and 71.4% of males expressed the wish to become thinner while 28.6% of the overweight/obese males wanted to get heavier.

CONCLUSION

The results of this study indicate a high rate of body image dissatisfaction and a tendency of participants to underestimate their body weight. This behavior may be a reflection of a real influence of social and psychological factors occurring during this critical period and may make university students vulnerable to many risk-taking behaviors. Thus, there is a need for suitable interventional programs and innovative strategies to ensure the understanding of the health consequences of overweight and obesity and to prevent associated comorbidities.

Molecular detection of Brucella melitensis, Coxiella burnetii and Salmonella abortusovis in aborted fetuses of Baluchi sheep in Sistan region, south-eastern Iran

Abortion in sheep and goats causes enormous economic losses. This study revealed the epidemiology of abortion caused by Brucella melitensis, Coxiella burnetii and Salmonella abortusovis in Baluchi sheep in Sistan region. In the autumn of 2015 and winter of 2016, a total of 78 aborted sheep fetuses were collected from all over the Sistan region. Risk factors, including location of livestock, history of abortion, gender of fetus, age of fetus, age of ewe and parity were obtained using a questionnaire. The results showed that 27 fetuses (35%) were infected with these organisms. Infection with B. melitensis, C. burnetii and S. abortusovis were identified respectively in 15 (19.2%), 13 (16.6%) and 1 (1.3%) fetus. Logistic regression analysis showed that infection with B. melitensis in male fetuses is higher than females (OR=3.73, P=0.040), also infection with C. burnetii in ≤2 years' ewes (OR=0.047, P=0.009) and 2-5 years' ewes (OR=0.197, P=0.069) is lower than ≥5 years' ewes.

Current immunogenetic predisposition to tuberculosis in the Moroccan population

Tuberculosis (TB) is a serious infectious disease that kills approximately two million people per year, particularly in low- and middle-income countries. Numerous genetic epidemiology studies have been conducted of many ethnic groups worldwide and have highlighted the critical impact of the genetic environment on TB distribution. Many candidate genes associated with resistance or susceptibility to TB have been identified. In Morocco, where TB is still a major public health problem, various observations of clinical, microbiological and incidence distribution are heavily affected by genetic background and external environment. Morocco has almost the same clinical profile as do other North African countries, mainly the increase in more extrapulmonary than pulmonary forms of the diseases, when compared to European, Asian or American populations. In addition, a linkage analysis study that examined Moroccan TB patients identified a unique chromosome region that had a strong association with the risk of contracting TB. Other genes in the Moroccan population that were found to be associated seem to be involved predominantly in modulating the innate immunity. In this review, we appraise the major candidate genes that have been reported in Moroccan immunogenetic studies and discuss their updated role in TB, particularly during the first phase of the immune response to Mycobacterium tuberculosis (Mtb) infection.

Cyclosporine A disposition, hepatic and renal tolerance in Wistar rat

Cyclosporine A, a potent calcineurin inhibitor, has been widely used in organ transplantation and in the treatment of autoimmune diseases. It has, however, been shown to induce serious renal and hepatic side effects. The drug is also used in preclinical studies, but with little published information on the optimal dose and route of administration in rodents. Objectives of this study were to identify efficient and safe doses of cyclosporine A in rodent and to assess its effects on hepatic and renal functions. For this purpose, we tested the effects of different doses and administration routes of cyclosporine A (5, 2.5 and 1 mg/kg) administered during 28 days intraperitoneally, or by gastric feeding on Wistar rats. Our data indicate that rats injected intraperitoneally with 5 mg/kg/2d (every two days) exhibited trough cyclosporine A levels within known therapeutic range in human, but were subject to blood cyclosporine A accumulation, whereas the 5 mg/kg/d gavage resulted in only a small cyclosporine A accumulation over time. In both cases this accumulation was not deleterious to renal and hepatic functions, as shown by transaminase, urea, creatinine and bilirubin measurements.

Syncoilin is an intermediate filament protein in activated hepatic stellate cells

Hepatic stellate cells (HSCs) play an important role in several (patho)physiologic conditions in the liver. In response to chronic injury, HSCs are activated and change from quiescent to myofibroblast-like cells with contractile properties. This shift in phenotype is accompanied by a change in expression of intermediate filament (IF) proteins. HSCs express a broad, but variable spectrum of IF proteins. In muscle, syncoilin was identified as an alpha-dystrobrevin binding protein with sequence homology to IF proteins. We investigated the expression of syncoilin in mouse and human HSCs. Syncoilin expression in isolated and cultured HSCs was studied by qPCR, Western blotting, and fluorescence immunocytochemistry. Syncoilin expression was also evaluated in other primary liver cell types and in in vivo-activated HSCs as well as total liver samples from fibrotic mice and cirrhotic patients. Syncoilin mRNA was present in human and mouse HSCs and was highly expressed in in vitro- and in vivo-activated HSCs. Syncoilin protein was strongly upregulated during in vitro activation of HSCs and undetectable in hepatocytes and liver sinusoidal endothelial cells. Syncoilin mRNA levels were elevated in both CCl4- and common bile duct ligation-treated mice. Syncoilin immunocytochemistry revealed filamentous staining in activated mouse HSCs that partially colocalized with α-smooth muscle actin, β-actin, desmin, and α-tubulin. We show that in the liver, syncoilin is predominantly expressed by activated HSCs and displays very low-expression levels in other liver cell types, making it a good marker of activated HSCs. During in vitro activation of mouse HSCs, syncoilin is able to form filamentous structures or at least to closely interact with existing cellular filaments.

Hepatocyte Transplantation Using the Domino Concept in a Child with Tetrabiopterin Nonresponsive Phenylketonuria

Phenylketonuria is a metabolic disease caused by phenylalanine hydroxylase deficiency. Treatment is based on a strict natural protein-restricted diet that is associated with the risk of malnutrition and severe psychosocial burden. Oral administration of tetrahydrobiopterin can increase residual enzyme activity, but most patients with severe clinical phenotypes are nonresponders. We performed liver cell transplantation in a 6-year-old boy with severe tetrahydrobiopterin nonresponsive phenylketonuria who failed to comply with diet prescriptions. The transplanted hepatocytes were obtained in part from an explanted glycogen storage type 1b liver. Following two infusions, blood phenylalanine levels returned within the therapeutic target while the phenylalanine half-life assessed by loading tests decreased from 43 to 19 h. However, 3 months later, blood phenylalanine concentrations increased and the phenylalanine intake had to be reduced. Cell-based therapy is a promising therapeutic option in phenylketonuria, and the domino concept may solve the issue of cell sources for hepatocyte transplantation.

Stem and progenitor cells for liver repopulation: can we standardise the process from bench to bedside?

There has been recent progress in the isolation and characterisation of stem/progenitor cells that may differentiate towards the hepatic lineage. This has raised expectations that therapy of genetic or acquired liver disease might be possible by transplanting stem/progenitor cells or their liver-committed progeny. However, it is currently impossible to determine from the many documented studies which of the stem/progenitor cell populations are the best for therapy of a given disease. This is largely because of the great variability in methods used to characterise cells and their differentiation ability, variability in transplantation models and inconsistent methods to determine the effect of cell grafting in vivo. This manuscript represents a first proposal, created by a group of investigators ranging from basic biologists to clinical hepatologists. It aims to define standardised methods to assess stem/progenitor cells or their hepatic lineage-committed progeny that could be used for cell therapy in liver disease. Furthermore standardisation is suggested both for preclinical animal models to evaluate the ability of such cells to repopulate the liver functionally, and for the ongoing clinical trials using mature hepatocytes. Only when these measures have been put in place will the promise of stem/progenitor-derived hepatocyte-based therapies become reality.

Persistence of a chimerical phenotype after hepatocyte differentiation of human bone marrow mesenchymal stem cells

OBJECTIVES

Recent studies have suggested the potential of mesenchymal stem cells (MSCs) to differentiate into a hepatocyte-like lineage. Here, we evaluate the efficacy of hepatocyte differentiation of MSCs by studying acquisition of hepatocyte-like features together with alteration of the native mesenchymal phenotype.

MATERIAL AND METHODS

In vitro, we have investigated protein and mRNA level expression of hepatocyte and mesenchymal markers of mesenchymal-derived hepatocyte-like cells (MDHLCs) and we have evaluated their functionality using metabolic assays. In vivo, we investigated co-expression of hepatocyte (albumin, alpha-foetoprotein, cytokeratin 18) and mesenchymal (fibronectin, vimentin) markers after transplantation of MSCs or MDHLCs into severe combined immune deficiency mice.

RESULTS

We observed that while in vitro these cells acquired some phenotypic and functional features of mature hepatocytes, they partially preserved their mesenchymal phenotype. After intrasplenic transplantation, engrafted MSCs with isolated expression of fibronectin and alpha-foetoprotein were observed. When these cells were injected into the liver, they expressed all analysed markers, confirming the chimaeric co-expression observed in vitro. Conversely, liver-engrafted MDHLCs conserved their hepatocyte-lineage markers but lost their chimaeric phenotype.

CONCLUSIONS

Hepatocyte differentiation of MSCs predominantly allows the acquisition of phenotypic hallmarks and provides chimaeric cells that maintain expression of initial lineage markers. However, advanced maturation to the hepatocyte-like phenotype could be obtained in vivo by conditioning MSCs prior to transplantation or by infusing cells into the liver micro-environment.

Cell transplantation in the treatment of liver diseases

The liver performs multiple functions that are essential for life, the most crucial being its role in the body metabolism. Impairment of this function, because of liver insufficiency, can be partially restored by medical management but OLT remains the ultimate therapeutic treatment. Because not always indicated or available, other alternatives are proposed such as LCT. Compared to OLT, this procedure is less invasive, less expensive, and fully reversible. More than 50 patients have thus far benefited of this technique and are reviewed here. Indications were multiple including inborn errors of metabolism, FHF, acute on chronic diseases, and decompensated end-stage cirrhosis. Documented results were encouraging, especially for metabolic disorders, with medium-term efficacy up to two yr. Related complications were exceptional. On this basis, LCT has entered its phase of clinical application and current indications and protocols are detailed. Ongoing lines of research are discussed, including cell quality, stem cell field, and rejection prevention. Further improvement of the procedure is therefore expected and should lead to broader applications of LCT.

Liver cell transplantation

Liver cell transplantation is an emerging procedure, consisting of infusing mature adult hepatocytes in the portal system of the recipient. It aims to correct inborn errors of liver metabolism, bridge unstable patients to transplantation, or even allow bridge to recovery in fulminant liver failure. The technique addresses ideally patients with inborn errors of metabolism, unstable but not sick enough for orthotopic transplantation. Best results have so far been obtained in metabolic diseases, such as urea cycle disorders, glycogenosis type I, Crigler Najjar, Refsum disease and factor VII deficiency. Cryopreserved hepatocytes can be used, allowing delay between cell isolation and patient's transplantation. The percentage of engraftment obtained can reach up 10%, with de novo expression of deficient enzyme activity. Better results of engraftment have been obtained in animal studies by different chemical or physical techniques, but not yet applied in humans. Because supply of human cells can be limited, research also aims to obtain transplantable cells from other sources, such as embryonic or adult stem cells, or liver progenitor cells that could be expanded in vitro. Careful progression in this field, and collaboration between centers are mandatory to validate further the technique for wider clinical use.

Allosteric modulation of GABAA receptor by somatostatin is altered under stress in rat brainstem

This study was conducted to investigate somatostatin modulation of GABAA receptor binding in several rat brainstem structures, located principally in the mesencephalon, after exposure to acute immobilization stress (single 1-hour session). Animals were randomly assigned to either control or stress conditions and changes in specific binding of the GABAA receptor as labelled with TBPS were assessed by in vitro quantitative autoradiography with the aid of a computer-assisted image analysis system. Exposure to immobilization stress led to a significant increase in [35S]TBPS binding site density in the SN of stressed rats compared to controls. In the other brainstem structures analysed, specific binding of [35S]TBPS remained unchanged in stressed rats. Furthermore, the results of the present in vitro study demonstrate an alteration of the modulatory effect of somatostatin on the GABAA receptor complex in the SN of stressed rats as compared to controls. This apparent alteration of allosteric effects of GABA receptor-somatostatin in the SN of stressed rats was eliminated in the presence of 1 micromolar concentration of GABA. Taken together, these data provide the first evidence of stress-induced alteration of allosteric effects of GABA-somatostatin in the rat mesencephalon. Furthermore, they also demonstrate that the tetradecapeptide somatostatin is particularly effective in modifying the [35S]TBPS binding to the GABAA receptor in this cerebral region.

Modulation Of [35S]-tert-butylbicyclophosphorothionate binding by somatostatin in rat hypothalamus

1. The present study was designed to assess the effect of the tetradecapeptide somatostatin on the GABA(A) receptor complex in the rat hypothalamus. 2. GABA(A) receptors were labelled with [35S]-tert-butylbicyclophosphorothionate (TBPS), which binds in or near the chloride channel, and binding as assessed by in vitro quantitative autoradiography using a computer-assisted image analysis system. 3. Somatostatin inhibited the binding of [35S]-TBPS to the convulsant site of the hypothalamic GABA(A) receptor complex of rat slide-mounted hypothalamic structures in a concentration-dependent manner with an affinity in the micromolar range (10(-6) to 3 x 10(-6) mol/L). Somatostatin appeared to mimic the effects of the neurosteroid 5alpha-pregnane-3alpha ol-one (5alpha3alphaP), GABA and picrotoxin on [35S]-TBPS binding in the rat hypothalamus in all structures examined. Furthermore, GABA or muscimol (a GABA(A) receptor agonist), when added to the incubation medium, enhanced the capacity of somatostatin to inhibit [35S]-TBPS binding, with an IC50 of 10(-7) mol/L. However, incubation with bicuculline (a GABA(A) receptor antagonist) led to the abolition of the inhibitory effect of somatostatin on [35S]-TBPS specific binding in rat hypothalamus. 4. The present results demonstrate the presence of a modulatory effect of somatostatin on the GABA(A) receptor complex in rat hypothalamic structures. Furthermore, the data suggest that somatostatin allosterically modifies [35S]-TBPS binding through a mechanism similar to that of GABA. Taken together, these results provide evidence for the presence of somatostatin- GABA interactions in rat hypothalamus.

Transcriptional regulation of the tyrosine hydroxylase gene by neurotensin in human neuroblastoma CHP212 cells

The human neuroblastoma cell line CHP212 was found to express functional high affinity neurotensin (NTS-1) receptor subtype. Based on the functional interactions between neurotensin and dopamine transmission, we have used this cell line to investigate the short- and long-term modulation of tyrosine hydroxylase gene expression by the stable neurotensin agonist JMV 449. After exposure of the cells to 1 microM JMV 449 for 5 or 72 h, tyrosine hydroxylase protein and mRNA levels were significantly increased as detected by western blot analysis and quantitative RT-PCR, respectively. Transfection of CHP212 cells with a plasmid containing the luciferase reporter gene under the control of a limited proximal region of the cloned tyrosine hydroxylase promoter, revealed that the effect of JMV 449 results from an increase in the transcriptional activity of the TH gene. These results indicate that modulation of tyrosine hydroxylase gene expression may constitute one of the mechanisms involved in the control of dopamine transmission by neurotensin. Such neurotensin-mediated changes in tyrosine hydroxylase expression may also participate in multiple adaptation processes within the central nervous system to environmental conditions where neurotensin is released such as stress and food intake.

Distribution of delta sleep-inducing peptide in the newborn and infant human hypothalamus: an immunohistochemical study

The distribution of delta sleep-inducing peptide immunoreactive cell bodies, fibers, and terminal-like structures was investigated in the normal human hypothalamus during the first postnatal year, using immunohistofluorescence and peroxidase anti-peroxidase techniques. Immunolabeled perikarya were relatively few and were mostly scattered through the anterior (preoptic) and mediobasal regions (infundibular nucleus) of the hypothalamus. DSIP-immunoreactive fibers and terminal-like fibers were observed throughout the entire rostrocaudal extent of the hypothalamus. They exhibit high densities in the preoptic region, the organum vasculosum of lamina terminalis, infundibular nucleus and median eminence. Moderate to low densities of DSIP-immunoreactive fibers were observed in the other hypothalamic structures, located in the anterior and mediobasal regions of hypothalamus, such as periventricular, paraventricular, suprachiasmatic, ventromedial, dorsomedial and parafornical nuclei. In the present study, the analysis of the immunohistochemical pattern of DSIP-immunoreactive neuronal elements in the human infant hypothalamus during the first postnatal year provided evidence of the presence of several differences. We have found qualitative age-related changes in the density of DSIP immunoreactivity in several hypothalamic structures such as the anterior region and the median eminence.

Immunohistochemical distribution of DSIP immunoreactivity in the human hypothalamus during the first postnatal year. A preliminary report

The distribution of DSIP-IR cell bodies and fibers was investigated in the normal human hypothalamus during the first postnatal year using the indirect immunofluorescence technique. The analysis of the immunohistochemical patterns obtained in the seven cases analyzed showed regional differences in the localization of cell bodies and fibers. Immunoreactive perikarya were relatively few, and were mostly scattered throughout the anterior and the mediobasal hypothalamus. DSIP-IR fibers and terminal-like structures were observed throughout the rostro-caudal extent of the hypothalamic region. In the present study, we noticed qualitative changes in the density of DSIP immunoreactivity in several hypothalamic structures such as the preoptic area and the median eminence with respect to age. These postnatal differences observed for DSIP could be related to neuronal maturation processes occurring at this period in the central nervous system as well as other physiological processes controlling the evolution of DSIP concentrations. These data are compatible with the proposed role of the neuropeptide in the regulation of many postnatal physiological functions.

Allosteric modulation of the GABA(A) receptor in rat hypothalamus by somatostatin is altered by stress

1. This autoradiographic study was conducted to investigate somatostatin modulation of GABA(A) receptor binding in hypothalamic structures of immobilization-stressed rats. 2. GABA(A) receptor binding was labelled with [35S]-t- butylbicyclophosphorothionate (TBPS), which binds in or near the chloride channel. 3. Several structures of the rat hypothalamus (i.e. the peri- and paraventricular nuclei) display an increase in [35S]-TBPS binding as well as an alteration of the modulatory effect of somatostatin on the GABA(A) receptor complex under stress. Furthermore, these results demonstrate for the first time that somatostatin is particularly effective in modifying [35S]-TBPS binding to the GABA(A) receptor in rat hypothalamus.

Regional distribution of benzodiazepine binding sites in the human newborn and infant hypothalamus. A quantitative autoradiographic study

Using in vitro quantitative autoradiography and [3H]flunitrazepam we examined the rostrocaudal distribution of benzodiazepine binding sites in the human neonate/infant hypothalamus. The autoradiographic analysis shows the presence of a heterogeneous distribution throughout the rostrocaudal extent of this brain structure. High [3H]flunitrazepam binding corresponds primarily to the diagonal band of Broca and the preoptic region. The labelling in the preoptic region showed a rostrocaudal increase, contrasting in that with the other hypothalamic structures. Intermediate densities were present in the septohypothalamic, suprachiasmatic, periventricular and paraventricular nuclei as well as in the mammillary complex. Low binding was observed in the other hypothalamic structures. The benzodiazepine binding sites analyzed belong mostly to type II receptors. In an attempt to unravel possible differences related to age, we compared the autoradiographic distribution in three postnatal age ranges. The topographical distribution of these binding sites was almost identical in each period analyzed. We found, however, that benzodiazepine binding is generally low in the neonatal period and a tendency in increasing densities is observed during development. Taken together, these results provide evidence for a large distribution of benzodiazepine binding sites in neonate/infant hypothalamus, suggesting their implication in the development of this brain structure and the maintenance of its various functions.

Modulation of the neuronal dopamine transporter activity by the metabotropic glutamate receptor mGluR5 in rat striatal synaptosomes through phosphorylation mediated processes

There is considerable evidence that the activity of the neuronal dopamine transporter (DAT) is dynamically regulated and a putative implication of its phosphorylation in this process has been proposed. However, there is little information available regarding the nature of physiological stimuli that contribute to the endogenous control of the DAT function. Based on the close relationship between glutamatergic and dopaminergic systems in the striatum, we investigated the modulation of the DAT activity by metabotropic glutamate receptors (mGluRs). Short-term incubations of rat striatal synaptosomes with micromolar concentrations of the group I mGluR selective agonist (S)-3,5-dihydroxyphenylglycine were found to significantly decrease the DAT capacity and efficiency. This alteration was completely prevented by a highly selective mGluR5 antagonist, 2-methyl-6-(phenylethynyl)pyridine hydrochloride (MPEP). The effect of (S)-3,5-dihydroxyphenylglycine was also inhibited by staurosporine and by selective inhibitors of protein kinase C and calcium calmodulin-dependent protein kinase II. Co-application of okadaic acid prolonged the transient effect of the agonist, supporting a critical role for phosphorylation in the modulation of the DAT activity by mGluRs. In conclusion, we propose that striatal mGluR5 contribute to the control of the DAT activity through concomitant activation of both protein kinase C and calcium calmodulin-dependent protein kinase II.

Evidence for the dual coupling of the rat neurotensin receptor with pertussis toxin-sensitive and insensitive G-proteins

We previously demonstrated the functional coupling of the rat neurotensin receptor NTS1 with G-proteins on transfected CHO cell homogenates by showing modulation of agonist affinity by guanylyl nucleotides and agonist-mediated stimulation of [(35)S]GTP gamma S binding. In the present study, we observed that G(i/o)-type G-protein inactivation by pertussis toxin (PTx) resulted in a dramatic reduction of the NT-induced [(35)S]GTP gamma S binding whereas the effect of guanylyl nucleotide was almost not affected. As expected, NT-mediated phosphoinositide hydrolysis and intracellular calcium mobilization were not altered after PTx treatment. This suggests the existence of multiple signaling cascades activated by NT. Accordingly, using PTx and the PLC inhibitor U-73122, we showed that both signaling pathways contribute to the NT-mediated production of arachidonic acid. These results support evidence for a dual coupling of the NTS1 with PTx-sensitive and insensitive G-proteins.

Benzodiazepine binding sites in the human hypothalamus. Autoradiographic study

Using in vitro labelling and autoradiographic techniques, we have analyzed the fine and the detailed distribution of benzodiazepine binding sites in the post-mortem human hypothalamus. Binding sites were labelled in mounted tissue sections from adult brains, using the selective high affinity ligand [3H]-Flunitrazepam. A heterogeneous distribution of benzodiazepine binding sites was found throughout the rostrocaudal extent of human hypothalamus. The autoradiographic labelling was shown in the three hypothalamic parts, i.e., anterior, mediobasal and posterior levels. At the anterior level, the highest densities were present in the diagonal band of Broca, the preoptic area (medial and lateral parts) and the septohypothalamic nucleus. At the mediobasal hypothalamic level, the highest densities were mainly localized in the ventromedial nucleus, whereas the other structures were moderately labelled with [3H]-Flunitrazepam. The mammillary complex as well as the posterior hypothalamic area represented the most heavily labelled structures in the posterior hypothalamus. The results obtained in this study, indicate the presence of a large and heterogeneous distribution of benzodiazepine binding sites in human adult hypothalamus. This could support their implication in the control of distinct neural functions (like neuroendocrine role).

Modulation of central GABAA receptor complex by somatostatin: a pharmacological study

The goal of the present study was to determine the possible interactions between somatostatin (SST) and gamma-aminobutyric acid (GABA). We thus investigated the SST interaction with [35S]-tertiary butylbicyclophosphorothionate (TBPS) binding sites of the cortical and hippocampal regions of the rat brain. The method used to identify such effects is in vitro quantitative autoradiography. Thus, the binding of the cage convulsant [35S]-TBPS to a picrotoxin-sensitive site in the rat brain was used to investigate the modulatory action of SST on the GABAA receptor complex. The addition of the peptide to the incubation medium results in a dose-dependent inhibition of [35S]-TBPS in cortical and hippocampal structures. Detailed analysis showed a dose-related effect of SST with relative potencies comparable to those observed for 5 alpha 3 alpha P and 5 beta 3 alpha P. In addition, these neurosteroids were able to enhance the efficacy of SST in inhibiting [35S]-TBPS binding. The efficacy of SST in enhancing the inhibitory action of neurosteroids was also evidenced. Furthermore, SST seems to mimic the effects of these neurosteroids as well as GABA and picrotoxin on [35S]-TBPS binding to the rat brain in every context examined. This suggests that somatostatin allosterically modifies [35S]-TBPS binding through a mechanism similar to that of GABA. On the other hand, a possible action of SST via transduction systems on the GABAA receptor complex could also be suggested. These results illustrate the importance of interactions in SST-mediated GABA transmission in these brain regions.

Activation of receptor gene transcription is required to maintain cell sensitization after agonist exposure. Study on neurotensin receptor

Neurotensin (NT) acts through specific G protein-coupled receptors to induce effects in the central nervous system and periphery. In this study we have shown that in the human neuroblastoma cell line CHP 212, an NT agonist, JMV 449, induced high affinity neurotensin receptor (NTR) gene activation. 125I-NT binding of cells challenged with JMV 449 rapidly decreased then reappeared and subsequently stabilized at 50% of the control values after 48 h of agonist exposure. These receptors, which reappeared at the cell surface, are as active as those found in control cells as demonstrated by Ca2+ mobilization. Furthermore, the tyrosine hydroxylase (TH) gene, a known NT target gene, remained activated after prolonged NT agonist exposure in this cell line. In the murine neuroblastoma cell line, N1E-115, NT did not stimulate NTR gene activation but induced NTR mRNA destabilization after long term agonist exposure. In this cell line, NT binding dropped to 15% of control values and remained at this value after agonist treatment. The TH expression, which was originally activated upon NT agonist exposure, decreased to control values after prolonged agonist exposure. These observations combined with the data obtained from a complementary study with HT-29 cells (Souazé, F., Rostène, W., and Forgez, P. (1997) J. Biol. Chem. 272, 10087-10094) revealed the crucial role of agonist-induced receptor gene transcription in the maintenance of cell sensitivity. A model for G protein-coupled receptor regulation induced by prolong and intense agonist stimulation is proposed.

Potentiation by propranolol of stress-induced changes in passive avoidance and open-field emergence tests in mice

Noradrenergic and serotonergic systems are known to be stimulated during various forms of stress. The present study examined the effect of the beta-adrenergic serotonin1A receptor blocker propranolol on the ability of stress to elicit behavioral inhibition in mice. Mice were given the drug before immobilization or tube-restraint stress, and then were tested for either passive avoidance performance or time to emerge into an open field. Propranolol markedly potentiated stress-induced increases in latency in both of these tests, suggesting that it exacerbated reactions to stress. These results agree with previous data indicating that under certain conditions, propranolol can potentiate the effects of stress in rodents. The results support the hypothesis that the response of the noradrenergic and/or serotonergic systems to stress may have anxiolytic or antistress effects.

Localization and developmental pattern of vasoactive intestinal polypeptide binding sites in the human hypothalamus

Using a quantitative in vitro autoradiographic approach, vasoactive intestinal polypeptide (VIP) binding site densities were compared in the post-mortem hypothalamus of human neonate/infant and adult. The densities were similar during development in most of the hypothalamic nuclei and areas examined underlying the stability of 125I-VIP binding sites in the post-mortem hypothalamus of young and adult individuals. However, the ventral part of the medial preoptic area, the medial, lateral, and supramammillary nuclei were characterized by an increase of 125I-VIP binding with age. In young and adult individuals, the highest densities of hypothalamic 125I-VIP binding sites were detected in the supraoptic and infundibular nuclei; the ependyma; the organum vasculosum of the lamina terminalis; the horizontal limb of the diagonal band of Broca; the ventral part of the medial preoptic area (in adult); the suprachiasmatic, paraventricular, and periventricular nuclei; and the medial and lateral mammillary nuclei in adult. Moderate densities were found in the vertical limb of the diagonal band of Broca, the bed nucleus of the stria terminalis, the ventral part of the medial preoptic area in neonate/infant, the medial and lateral mammillary nuclei in neonate/infant, the supramammillary nucleus in adult, the dorsal hypothalamic area, and the ventromedial nucleus. Low to moderate binding site densities were observed in the other hypothalamic regions of young or adult individuals. The nonspecific binding ranged from 15% of the total binding in the anterior hypothalamus to 20% in the mediobasal and posterior hypothalamic levels. Taken together, these results provide evidence for a large distribution of VIP binding sites in neonate/infant and adult human hypothalamus suggesting the implication of VIP in the development of this brain structure and the maintenance of its various functions.

Evidence for a substance P containing subpopulation in the primate suprachiasmatic nucleus

Immunohistochemical detection of substance P (SP) in the suprachiasmatic nucleus (SCN) of the Old World monkey, Macaca fascicularis, was performed using two different rabbit polyclonal antisera. Immunostaining revealed a large population of neurons located in the dorsal subdivision of the nucleus identified by Nissl stain. This neuronal group represents the only cluster of SP-like immunoreactive (SP-IR) perikarya observed within the hypothalamus. In contrast with our present finding in the macaque, earlier studies only reported a few scattered SP-IR neurons in the SCN of other mammalian species. In agreement with previous descriptions of neuropeptides in the SCN, the topographical distribution of SP-IR neurons in the monkey confirms that cellular segregation is a significant feature of the mammalian SCN. This particular peptidergic subpopulation may represent a characteristic of the monkey circadian pacemaker. Together with other anatomical data previously reported in monkey and man, this finding also relates to the anatomical evolution of the circadian system from non-primates to humans. Although convincing data support the implication of SP in cyclic neuroendocrine regulations, the role of this tachykinin in circadian rhythmicity remains to be elucidated.

Quantitative autoradiographic study of somatostatin and neurotensin binding sites in medulla oblongata of sids☆

Quantitative autoradiography analysis of neurotensin (NT) and somatostatin (SS) binding sites was performed on coronal sections of the medulla oblongata from 2 fetuses, 6 controls and 7 victims of Sudden Infant Death Syndrome (SIDS). Throughout the first postnatal year, mean SS binding site density was similar in controls and SIDS in all structures of the medulla oblongata. The density of neurotensin binding sites was significantly higher in the nucleus of tractus solitarius (NTS) of SIDS than in controls, but there was no significant differences in the other areas of the medulla oblongata. Our findings suggest an immature developmental pattern of increased NT binding sites the NTS of SIDS. This alteration may be related to an abnormal central cardiorespiratory and arousal control which is thought to be present in SIDS.

Ontogeny of peptides in human hypothalamus in relation to sudden infant death syndrome (SIDS)

The brains of mammals are not mature at birth, in particular in humans. Growth and brain development are influenced by the hormonal state in which the hypothalamus plays the major regulatory role. The maturation of the hormonal patterns leads to the physiological establishment of chronological variations as revealed by the circadian variations of both hypothalamic peptides and pituitary hormones (as illustrated for hypothalamic-pituitary-thyroid axis by the determination of thyro-stimulating hormone (TSH) and thyrotropin-releasing hormone (TRH) circadian rhythms in the rat (Jordan et al., 1989)). It has been established that hypothalamic peptide variations are regulated by hormonal feed-back and amine systems, with the maturation of the latter also being dependent upon the whole functional maturation of the brain. Though these systems have been studied in the rat, very little information is currently available with regard to the human brain. The only biochemical or immunohistochemical information published to date concerns either the fetus or the adult. We have studied four main peptidergic systems (somatostatin-releasing inhibiting factor (SRIF), thyrotropin-releasing hormone (TRH), luteinizing hormone-releasing hormone (LHRH) and delta sleep inducing peptide (DSIP) in post-mortem adults and infants and in sudden infant death syndrome (SIDS) brains either by autoradiography and/or immunochemistry of radioimmunology. From a technical point of view, human brain studies display certain pitfalls not present in animal studies. These may be divided into two subclasses: ante- and post-mortem. Ante-mortem problems concern mainly sex, laterality, nutritional and treatment patterns while post-mortem problems concern post-mortem delay and conditions before autopsy and hypothalamic dissection. This might induce dramatic changes in morphological, immunochemical and autoradiographic evaluations. The matching of pathological subjects with controls is particularly difficult in the case of SIDS because of the rapid changes which take place in physiological regulatory processes during the first year of life. Thus, the treatment of hypothalamic tissue samples both for immunochemistry, radioimmunology and autoradiographic studies required techniques which must be rigorously controlled. For example, SRIF studies were carried out with three different antibodies, which gave similar results. The use of different technical procedures as well as different antibodies is discussed. These types of differences might explain, at least in part, the discrepancy observed until now. As previously described in the fetus (Bugnon et al., 1977b; Bouras et al., 1987), we confirmed that in the infant hypothalamic SRIF immunoreactive cell bodies are present in the paraventricular and suprachiasmatic nuclei and in the periventricular area.(ABSTRACT TRUNCATED AT 400 WORDS)

Autoradiographic distribution of TRH binding sites in the human hypothalamus

Using in vitro quantitative autoradiography and [3H]3MeTRH, a selective high affinity radioligand, we examined the rostrocaudal distribution of TRH binding sites in both the infant and the adult human hypothalamus. The saturation curve shows that the [3H]3MeTRH binds with high affinity to a single class of TRH binding sites and is saturable, the apparent constant of dissociation is in the namomolar range. TRH binding sites showed a wide distribution, principally in the anterior and mediobasal levels of the hypothalamus. TRH binding site concentration was highest within the diagonal band of Broca, the lateral preoptic area, the infundibular and the tuberal nuclei. TRH binding site concentration was moderate in the ventromedial nucleus and the medial preoptic area, whereas we observed low densities in the periventricular, paraventricular and mammillary nuclei. The distribution in the infant and the adult is generally similar. However, it is noteworthy that the infant tuberal nuclei displayed a lower binding site density when compared to the adult. On the other hand, the diagonal band of Broca is relatively more labeled in infant. The analysis of the whole hypothalamus allows us to ascertain the absence of lateral asymmetric distribution both in the infant and the adult. No significant difference is noticed when considering as parameters of variation age, sex or post mortem delay.

Anatomical distribution of substance P-immunoreactive neurons in human brainstem during the first postnatal year

The localization of substance P (SP)-immunoreactive structures in the infant brainstem was investigated by immunohistochemistry using the peroxidase antiperoxidase technique. SP-immunoreactive structures are widely distributed throughout the brainstem region. SP-immunoreactive cell bodies are prominent in the superior colliculis, the central grey, the nucleus tractus solitarius and the reticular formation. A high density of SP-immunoreactive fibers is found in the nucleus tractus solitarius, the trigeminal nucleus and the dorsal horn of the spinal cord. Large SP-immunoreactive fibers are seen in the substantia nigra. In the present study, we also investigated the development of substance P-immunoreactive fibers in the infant brainstem during the first postnatal year. We note a qualitative increase in the density of SP-immunoreactivity in some brainstem regions such as colliculus superior and substantia nigra with respect to age.

Regional distribution of somatostatin binding sites in the human hypothalamus: a quantitative autoradiographic study

Using in vitro quantitative autoradiography and [125I]Tyr0-D-Trp8SRIF 14 as radioligand, we characterized the detailed distribution of somatostatin binding sites in human hypothalamus of both infants and adults. Guanosine triphosphate pretreatment, before incubation, allowed us to detect higher [125I]Tyr0-D-Trp8SRIF 14 binding site densities in hypothalamic structures such as preoptic and anterior hypothalamic areas and ventromedial and dorsomedial nuclei. In contrast, guanosine triphosphate was without effect in the other hypothalamic regions. The regional effects of guanosine triphosphate pretreatment were not different in infant and adult hypothalamus. Scatchard analysis showed that in a guanosine triphosphate-sensitive region (preoptic area) and a guanosine triphosphate-insensitive area (infundibular nucleus), [125I]Tyr0-D-Trp8SRIF 14 bound to a single class of binding sites. Affinities were similar in both regions, not modified by guanosine triphosphate pretreatment and not different in the adult (1.5 +/- 1.2 nM vs 3.2 +/- 2.1 nM for preoptic area and infundibular nucleus, respectively) and infant (0.9 +/- 0.5 nM vs 2.4 +/- 1.7 nM for preoptic area and infundibular nucleus). [125I]Tyr0-D-Trp8SRIF 14 binding sites were widely distributed in the anterior, mediobasal and posterior hypothalamus. Somatostatin 28 was twice as potent as somatostatin 14 to displace [125I]Tyr0-D-Trp8SRIF 14 binding in the preoptic area and infundibular nucleus. However, IC50s were 30 times lower in the preoptic area as compared with the infundibular nucleus. In adult as well as in infant, high densities were found mainly in the diagonal band of Broca, preoptic area and infundibular nucleus. Intermediate densities were localized in the anterior hypothalamic area, ventromedial, dorsomedial and lateral mammillary nuclei. The dorsal hypothalamic area, the paraventricular and medial mammillary nuclei displayed low but measurable densities. The only marked difference in the distribution of [125I]Tyr0-D-Trp8SRIF 14 binding sites in adult vs infant was observed in the medial and tuberal nuclei where the concentrations were seven-fold higher in adult hypothalamus.

Anatomical distribution of LHRH-immunoreactive neurons in the human infant hypothalamus and extrahypothalamic regions

The morphological features and distribution of luteinizing hormone-releasing hormone (LHRH)-immunoreactive cell bodies and fibers of the hypothalamic and the neighboring mesencephalic regions were studied in the normal newborn infant by immunohistochemistry. Within the hypothalamus, numerous LHRH-immunoreactive like (IL) cell bodies were found mainly in the ventral portion of the infundibular nucleus close to the median eminence and at a lower extent in the medial preoptic area. In addition, sparse immunoreactive cell bodies were displayed in the paraventricular and medial mammillary nuclei. The mesencephalon also exhibited rare immunoreactive cell bodies in the periaqueductal gray. LHRH-IL fibers, predominantly varicose, formed a continuum from the septo-preoptico level to the mesencephalon. In the hypothalamus, the median eminence exhibited the highest LHRH innervation. LHRH-IL fibers are also observed in the lamina terminalis, the medial preoptic area, the suprachiasmatic, the supraoptic, the peri- and the paraventricular nuclei. In the last two nuclei, some fibers projected to the dorsomedial and ventromedial nuclei whereas others were in close relation with the ependyma. The mesencephalon displayed low LHRH-IL fibers, present essentially in the raphe and interpeduncular nuclei and around the ependyma. When compared with data obtained in other mammals, the present findings agree well with the general distribution and morphological features of LHRH-IL neuronal structures reported elsewhere.

Immunohistochemical distribution of somatostatin in the infant hypothalamus

Somatostatin (SS)-containing neurons were mapped in the normal infant hypothalamus with immunohistochemistry, using the peroxidase anti-peroxidase technique. Neurons displaying SS immunoreactivity show a widespread distribution throughout the hypothalamic region. Principal SS-immunoreactive like (SS-IL) perikarya are located in the paraventricular, infundibular and posterior nuclei and in the preoptic region. High SS innervation is also found in the ventromedial and in the lateral mammillary nuclei, and in the median eminence. In general this distribution of SS-IL agrees well with that reported for rat. Compared to the immunohistochemical distribution of SS in human adult hypothalamus, this mapping in the infant hypothalamus is grossly similar. However some differences may be underlined: the presence of a moderately dense group of SS-IL perikarya in the tuberal and posterior nuclei, and a dense innervation of the ventromedial nucleus and in the median eminence. This first detailed distribution of SS immunoreactivity in infant hypothalamus can provide basic knowledge for further studies of infant neuropathology.

Anatomical distribution of somatostatin immunoreactivity in the infant brainstem

The distribution of somatostatin-immunoreactive structures in the infant brainstem was investigated using the peroxidase-antiperoxidase technique. A wide distribution of somatostatin-immunoreactive cell bodies and fibers was observed throughout the brainstem. Numerous somatostatin-immunoreactive cell bodies and fibers were present in several areas of the brainstem including the substantia grisea centralis and the reticular formation. Some immunoreactive cell bodies were seen in cranial nerve nuclei such as the nucleus praepositus, the nucleus nervi hypoglossi and the vestibular nuclei. Immunoreactive fibers were seen in the nucleus cuneatus, the locus coeruleus, the nucleus tractus solitarius, the nucleus ambiguus, the nucleus tractus spinalis nervi trigemini and the dorsal horn of the spinal cord. These data were in agreement with previous works on the human adult. However, a high density of somatostatin-immunoreactive cell bodies and fibers in the interpeduncular nucleus and in the nucleus centralis superior, and a dense network of somatostatin-immunoreactive fibers in the dorsal part of the nucleus inferior olivarius, were also observed. The role of somatostatin in some brainstem nuclei and its probable implication in some specific neuropathological diseases of the infant brainstem is discussed.