bluuebunny/crossref_metadata_2025 huggingface dataset:
Altered gene and protein expression in liver of the obese spontaneously hypertensive/NDmcr-cp rat
Authors: Chang Jie , Oikawa Shinji , Ichihara Gaku , Nanpei Yui , Hotta Yasuhiro , Yamada Yoshiji , Tada-Oikawa Saeko , Iwahashi Hitoshi , Kitagawa Emiko , Takeuchi Ichiro , Yuda Masao , Ichihara Sahoko
Published: September 2012

Background

It is difficult to study the mechanisms of the metabolic syndrome in humans due to the heterogeneous genetic background and lifestyle. The present study investigated changes in the gene and protein profiles in an animal model of the metabolic syndrome to identify the molecular targets associated with the pathogenesis and progression of obesity related to the metabolic syndrome.

Methods

We extracted mRNAs and proteins from the liver tissues of 6- and 25-week-old spontaneously hypertensive/NIH –corpulent rat SHR/NDmcr-cp (CP), SHR/Lean (Lean) and Wistar Kyoto rats (WKY) and performed microarray analysis and two-dimensional difference in gel electrophoresis (2D-DIGE) linked to a matrix-assisted laser desorption ionization time-of-flight tandem mass spectrometry (MALDI-TOF/TOF MS).

Results

The microarray analysis identified 25 significantly up-regulated genes (P < 0.01; log10 > 1) and 31 significantly down-regulated genes (P < 0.01; log10 < −1) in 6- and 25-week-old CP compared with WKY and Lean. Several of these genes are known to be involved in important biological processes such as electron transporter activity, electron transport, lipid metabolism, ion transport, transferase, and ion channel activity. MALDI-TOF/TOF MS identified 31 proteins with ±1.2 fold change (P < 0.05) in 6- and 25-week-old CP, compared with age-matched WKY and Lean. The up-regulated proteins are involved in metabolic processes, biological regulation, catalytic activity, and binding, while the down-regulated proteins are involved in endoplasmic reticulum stress-related unfolded protein response.

Conclusion

Genes with significant changes in their expression in transcriptomic analysis matched very few of the proteins identified in proteomics analysis. However, annotated functional classifications might provide an important reference resource to understand the pathogenesis of obesity associated with the metabolic syndrome.
Time perception at different EEG-vigilance levels
Authors: Minkwitz Juliane , Trenner Maja U , Sander Christian , Olbrich Sebastian , Sheldrick Abigail J , Hegerl Ulrich , Himmerich Hubertus
Published: September 2012

Background

Human time perception is influenced by various factors such as attention and drowsiness. Nevertheless, the impact of cerebral vigilance fluctuations on temporal perception has not been sufficiently explored. We assumed that the state of vigilance ascertained by electroencephalography (EEG) during the perception of a given auditory rhythm would influence its reproduction. Thus, we hypothesised that the re-tapping interval length and the accuracy of reproduction performance would vary depending on the state of vigilance determined by EEG.

Methods

12 female and 9 male subjects ranging from 21 to 38 years (M = 25.52, SD = 3.75) participated in a test paradigm comprising a) a resting EEG for the determination of vigilance while an auditory rhythm was presented, b) a short activity of the proband to be sure of sufficient alertness, and c) a tapping task to reproduce the presented rhythm. Vigilance states of three consecutive 1-sec-EEG-segments of the resting EEG before the reproduction phase were classified using the Vigilance Algorithm Leipzig (VIGALL).

Results and discussion

Reproduction accuracy was more precise after high EEG-vigilance stages. Thus, the subjects’ mean deviation from the given rhythm was lower (t(17) = −2.733, p < 0.05) after high vigilance stage A (MW = 0.046, SD = 0.049) than after low vigilance stage B (MW = 0.065, SD = 0.067). The re-tapping-length was significantly shorter (t(17) = −2.190, p < 0.05) for reproduction phases following high EEG-vigilance stage A compared to the lower EEG-vigilance stage B.

Conclusion

These findings support the hypothesis of a varying time perception and of speed alterations of the internal clock after different states of EEG-vigilance, which were automatically classified by VIGALL. Thus, alterations of cognitive processing may be assessable by specific EEG-patterns.
One stage resection of spontaneous rupture of hepatocellular carcinoma in the triangular ligament with diaphragm invasion: case report and review of the literature
Authors: Park Kwang-Kuk , Yang Song-I , Yoon Myung-hee
Published: September 2012

A spontaneous rupture of hepatocellular carcinoma (HCC) can lead to extensive hemorrhage and is a rare but life-threatening event. A 58-year-old male patient with no history of trauma presented at our institution with severe epigastric pain and abdominal distension for 6 h. His blood pressure was a 60/40 mmHg, and pulse rate was 132/min. Abdominal contrast enhanced computed tomography (CT) imaging revealed a ruptured mass under the left diaphragm and fluid collection in the upper abdomen, flanks and pelvic cavity. Exploratory laparotomy confirmed the presence of an active bleeding tumor in the triangular ligament invading into the diaphragm. The tumor was resected with an appropriate diaphragm margin. The resected tumor was 5 cm in diameter and pathologically identified as hepatocellular carcinoma with a negative surgical margin. This case report shows that ruptured hepatocellular carcinoma should be considered in the differential diagnosis of non-traumatic hemoperitoneum. And it is necessary to set a surgical plan for unpredictable HCC rupture with direct diaphragm invasion.
Knowledge and attitudes of doctors regarding the provision of mental health care in Doddaballapur Taluk, Bangalore Rural district, Karnataka
Authors: Cowan Joshua , Raja Shoba , Naik Amali , Armstrong Gregory
Published: September 2012

Background

Specialist mental health care is out of reach for most Indians. The World Health Organisation has called for the integration of mental health into primary health care as a key strategy in closing the treatment gap. However, few studies in India have examined medical practitioners’ mental health-related knowledge and attitudes. This study examined these facets of service provision amongst doctors providing primary health care in a rural area of Karnataka is Southern India.

Methods

A mental health knowledge and attitudes questionnaire was self- administered by participants. The questionnaire consisted of four sections; 1) basic demographics and practice information, 2) training in mental health, 3) knowledge of mental health, and self-perceived competence in providing mental health care, and 4) attitudes towards mental health. Data was analysed quantitatively, primarily using descriptive statistics.

Results

This study recruited 46 participants. The majority of participants (69.6%) felt competent in providing mental health services to their patients. However, there was a substantial level of endorsement for several statements that reflected negative attitudes. Almost one third of participants (28.0%) had not received any training in providing mental health care. Whilst three-quarters of participants correctly identified depression (76.1%) and psychosis (76.1%) in a vignette, fewer were able to name three common signs and symptoms of depression (50.0%) and psychosis (28.3%).

Conclusions

Integrating mental health into primary health care requires evidence-based up-skilling programs. Doctors in this study desired such training and would benefit from it, with a focus on both depth of knowledge and uncovering stigmatising attitudes towards people with mental health problems.
Microbial β-glucosidases from cow rumen metagenome enhance the saccharification of lignocellulose in combination with commercial cellulase cocktail
Authors: Del Pozo Mercedes V , Fernández-Arrojo Lucía , Gil-Martínez Jorge , Montesinos Alejandro , Chernikova Tatyana N , Nechitaylo Taras Y , Waliszek Agnes , Tortajada Marta , Rojas Antonia , Huws Sharon A , Golyshina Olga V , Newbold Charles J , Polaina Julio , Ferrer Manuel , Golyshin Peter N
Published: September 2012

Background

A complete saccharification of plant polymers is the critical step in the efficient production of bio-alcohols. Beta-glucosidases acting in the degradation of intermediate gluco-oligosaccharides produced by cellulases limit the yield of the final product.

Results

In the present work, we have identified and then successfully cloned, expressed, purified and characterised 4 highly active beta-glucosidases from fibre-adherent microbial community from the cow rumen. The enzymes were most active at temperatures 45–55°C and pH 4.0-7.0 and exhibited high affinity and activity towards synthetic substrates such as p-nitrophenyl-beta-D-glucopyranoside (p NPbetaG) and p NP-beta-cellobiose, as well as to natural cello-oligosaccharides ranging from cellobiose to cellopentaose. The apparent capability of the most active beta-glucosidase, herein named LAB25g2, was tested for its ability to improve, at low dosage (31.25 units g-1 dry biomass, using p NPbetaG as substrate), the hydrolysis of pre-treated corn stover (dry matter content of 20%; 350 g glucan kg-1 dry biomass) in combination with a beta-glucosidase-deficient commercial Trichoderma reseei cellulase cocktail (5 units g-1 dry biomass in the basis of p NPbetaG). LAB25g2 increased the final hydrolysis yield by a factor of 20% (44.5 ± 1.7% vs. 34.5 ± 1.5% in control conditions) after 96–120 h as compared to control reactions in its absence or in the presence of other commercial beta-glucosidase preparations. The high stability (half-life higher than 5 days at 50°C and pH 5.2) and 2–38000 fold higher (as compared with reported beta-glucosidases) activity towards cello-oligosaccharides may account for its performance in supplementation assays.

Conclusions

The results suggest that beta-glucosidases from yet uncultured bacteria from animal digestomes may be of a potential interest for biotechnological processes related to the effective bio-ethanol production in combination with low dosage of commercial cellulases.
Analysis of the compatibility of dental implant systems in fibula free flap reconstruction
Authors: Carbiner Ramin , Jerjes Waseem , Shakib Kaveh , Giannoudis Peter V , Hopper Colin
Published: September 2012

As a result of major ablative surgery, head and neck oncology patients can be left with significant defects in the orofacial region. The resultant defect raises the need for advanced reconstruction techniques. The reconstruction in this region is aimed at restoring function and facial contour. The use of vascularised free flaps has revolutionised the reconstruction in the head and neck. Advances in reconstruction techniques have resulted in continuous improvement of oral rehabilitation. For example, endosteal implants are being used to restore the masticatory function by the way of prosthetic replacement of the dentition. Implant rehabilitation usually leads to improved facial appearance, function, restoration of speech and mastication. Suitable dental implant placement’s site requires satisfactory width, height and quality of bone. Reconstruction of hard tissue defects therefore will need to be tailored to meet the needs for implant placement.

The aim of this feasibility study was to assess the compatibility of five standard commercially available dental implant systems (Biomet 3i, Nobel Biocare, Astra tech, Straumann and Ankylos) for placement into vascularised fibula graft during the reconstruction of oromandibular region.

Radiographs (2D) of the lower extremities from 142 patients in the archives of the Department of Radiology in University College London Hospitals (UCLH) were analysed in this study. These radiographs were from 61 females and 81 males. Additionally, 60 unsexed dry fibular bones, 30 right sided, acquired from the collection of the Department of Anatomy, University College London (UCL) were also measured to account for the 3D factor.

In the right fibula (dry bone), 90% of the samples measured had a width of 13.1 mm. While in the left fibula (dry bone), 90% of the samples measured had a width of 13.3 mm. Fibulas measured on radiographs had a width of 14.3 mm in 90% of the samples. The length ranges of the dental implants used in this study were: 7-13 mm (Biomet 3i), 10-13 mm (Nobel biocare), 8-13 mm (Astra Tech), 8-12 mm (Straumann ) and 8-11 mm (Ankylos).

This study reached a conclusion that the width of fibula is sufficient for placement of most frequently used dental implants for oral rehabilitation after mandibular reconstructive procedures.
Feasibility of recruitment to an oral dysplasia trial in the United Kingdom
Authors: Nankivell Paul , Dunn Janet , Langman Michael , Mehanna Hisham
Published: September 2012

Background

Oral epithelial dysplasia (OED) has a malignant potential. Therapeutic options for OED remain both limited and without good evidence. Despite surgery being the most common method of treating OED, recurrence and potentially significant morbidity remain problematic. Consequently, there has been much interest in non-surgical treatments for OED. Cyclo-oxygenase (COX) up-regulation is known to occur in the dysplasia-carcinoma sequence and evidence now exists that COX-2 is a prognostic marker of malignant transformation in OED. COX-inhibitors are therefore considered a potential therapeutic strategy for treating this condition. We aimed to provide both proof of principal evidence supporting the effect of topical COX inhibition, and determine the feasibility of recruitment to an OED chemoprevention trial in the UK.

Methods

Recruitment of 40 patients with oral leukoplakia to 4 study arms was planned. The total daily dose of Aspirin would increase in each group and be used in the period between initial diagnostic and follow-up biopsies.

Results

During the 15-month recruitment period, 15/50 screened patients were eligible for recruitment, and 13 (87%) consented. Only 1 had OED diagnosed on biopsy. 16 patients were intolerant of, or already taking Aspirin and 16 patients required no biopsy. Initial recruitment was slow, as detection relied on clinicians identifying potentially eligible patients. Pre-screening new patient letters and directly contacting patients listed for biopsies improved screening of potentially eligible patients. However, as the incidence of OED was so low, it had little impact on trial recruitment. The trial was terminated, as recruitment was unlikely to be achieved in a single centre.

Conclusion

This feasibility trial has demonstrated the low incidence of OED in the UK and the difficulties in conducting a study because of this. With an incidence of around 1.5/100,000/year and a high proportion of those patients already taking or intolerant of Aspirin, a large multi-centred trial would be required to fulfil the recruitment for this study. The ability of topical non-steroidal anti-inflammatory drugs to modify COX and prostaglandin expression remains an important but unanswered question. Collaboration with centres in other parts of the world with higher incidences of the disease may be required to ensure adequate recruitment.

ISRCTN

31503555.
High throughput DNA sequencing to detect differences in the subgingival plaque microbiome in elderly subjects with and without dementia
Authors: Cockburn Andrew F , Dehlin Jonathan M , Ngan Tiffany , Crout Richard , Boskovic Goran , Denvir James , Primerano Donald , Plassman Brenda L , Wu Bei , Cuff Christopher F
Published: September 2012

Background

To investigate the potential association between oral health and cognitive function, a pilot study was conducted to evaluate high throughput DNA sequencing of the V3 region of the 16S ribosomal RNA gene for determining the relative abundance of bacterial taxa in subgingival plaque from older adults with or without dementia.

Methods

Subgingival plaque samples were obtained from ten individuals at least 70 years old who participated in a study to assess oral health and cognitive function. DNA was isolated from the samples and a gene segment from the V3 portion of the 16S bacterial ribosomal RNA gene was amplified and sequenced using an Illumina HiSeq1000 DNA sequencer. Bacterial populations found in the subgingival plaque were identified and assessed with respect to the cognitive status and oral health of the participants who provided the samples.

Results

More than two million high quality DNA sequences were obtained from each sample. Individuals differed greatly in the mix of phylotypes, but different sites from different subgingival depths in the same subject were usually similar. No consistent differences were observed in this small sample between subjects separated by levels of oral health, sex, or age; however a consistently higher level of Fusobacteriaceae and a generally lower level of Prevotellaceae was seen in subjects without dementia, although the difference did not reach statistical significance, possibly because of the small sample size.

Conclusions

The results from this pilot study provide suggestive evidence that alterations in the subgingival microbiome are associated with changes in cognitive function, and provide support for an expanded analysis of the role of the oral microbiome in dementia.
Advances in the pathogenesis of Alzheimer’s disease: a re-evaluation of amyloid cascade hypothesis
Authors: Dong Suzhen , Duan Yale , Hu Yinghe , Zhao Zheng
Published: September 2012

Alzheimer’s disease (AD) is a common neurodegenerative disease characterized clinically by progressive deterioration of memory, and pathologically by histopathological changes including extracellular deposits of amyloid-beta (A-beta) peptides forming senile plaques (SP) and the intracellular neurofibrillary tangles (NFT) of hyperphosphorylated tau in the brain. This review focused on the new developments of amyloid cascade hypothesis with details on the production, metabolism and clearance of A-beta, and the key roles of some important A-beta-related genes in the pathological processes of AD. The most recent research advances in genetics, neuropathology and pathogenesis of the disease were also discussed.
The relationship between serum 25-hydroxy vitamin D concentration and obesity in type 2 diabetic patients and healthy subjects
Authors: Taheri Ehsaneh , Saedisomeolia Ahmad , Djalali Mahmoud , Qorbani Mostafa , Madani Civi Manouchehr
Published: September 2012

Background

Both obesity and type 2 diabetes are associated with hypovitaminosis D. The aims of this study were to investigate the association of serum 25-hydroxy vitamin D (25(OH) D) and parathyroid hormone (PTH) concentration with body mass index (BMI) in type 2 diabetic patients compared to control subjects and their predicting role in obesity.

Methods

This cross-sectional study was conducted on 200 subjects (100 type 2 diabetics and 100 healthy controls). Concentration of 25(OH) D, calcium, phosphorous, parathyroid hormone (PTH), fasting blood glucose, HbA1c, serum insulin, homeostasis model assessment of insulin resistance (HOMA-IR) was determined in the fasting samples. Anthropometric measurements including body mass index (BMI) were also measured.

Results

Eighty-five percent of type 2 diabetics and 79% of healthy subjects were suffering from vitamin D deficiency or insufficiency. Serum concentration of 25(OH) D (22.08 ± 15.20 ng/ml) (r = −0.11, P = 0.04) and calcium (8.94 ± 0.59 mg/dl) (r = −2.25, P = 0.04) has significant statistically with BMI in type 2 diabetic patients. Serum concentration of PTH has non-significantly associated with BMI in diabetic patients and healthy subjects.

Conclusion

Serum levels of vitamin D inversely and PTH positively are associated with BMI after adjusted for age, gender and serum calcium in both type 2 diabetic patients and healthy subjects. These associations were statistically significant for serum concentration of vitamin D and calcium only in diabetic patients. So the status of vitamin D is considered as an important factor in type 2 diabetic patients.
Betel-quid dependence and oral potentially malignant disorders in six Asian countries
Authors: Lee Chien-Hung , Ko Albert Min-Shan , Yen Cheng-Fang , Chu Koung-Shing , Gao Yi-Jun , Warnakulasuriya Saman , Sunarjo  , Ibrahim Salah Osman , Zain Rosnah Binti , Patrick Walter K. , Ko Ying-Chin
Published: September 2012

Background

Despite gradual understanding of the multidimensional health consequences of betel-quid chewing, information on the effects of dependent use is scant.

Aims

To investigate the 12-month prevalence patterns of betel-quid dependence in six Asian populations and the impact of this dependence on oral potentially malignant disorders (OPMD).

Method

A multistage random sample of 8922 participants was recruited from Taiwan, mainland China, Indonesia, Malaysia, Sri Lanka and Nepal. Participants were evaluated for betel-quid dependency using DSM-IV and ICD-10 criteria and assessed clinically for oral mucosal lesions.

Results

The 12-month prevalence of dependence was 2.8-39.2% across the six Asian samples, and 20.9-99.6% of those who chewed betel-quid were betel-quid dependent. Men dominated the prevalence among the east Asian samples and women dominated the prevalence in south-east Asian samples. ‘Time spent chewing’ and ‘craving’ were the central dependence domains endorsed by the Chinese and southern/south-east Asian samples respectively, whereas the Nepalese samples endorsed ‘tolerance’ and ‘withdrawal’. Dependency was linked to age, gender, schooling years, drinking, smoking, tobacco-added betel-quid use and environmental accessibility of betel-quid. Compared with non-users, those with betel-quid dependency had higher pre-neoplastic risks (adjusted odds ratios 8.0-51.3) than people with non-dependent betel-quid use (adjusted odds ratio 4.5-5.9) in the six Asian populations.

Conclusions

By elucidating differences in domain-level symptoms of betel-quid dependency and individual and environmental factors, this study draws attention to the population-level psychiatric problems of betel-quid chewing that undermine health consequences for OPMD in six Asian communities.
Anxiety, distress and anger among British nationals in Japan
following the Fukushima nuclear accident
Authors: Rubin G. James , Amlôt Richard , Wessely Simon , Greenberg Neil
Published: September 2012

Background

The 2011 earthquake and tsunami in Japan caused a meltdown at the
Fukushima nuclear power plant.

Aims

To quantify emotional responses among British nationals in Japan and to
assess whether perceptions about the incident or accessing information
about it were associated with responses.

Method

A total of 284 participants randomly selected from official records
completed a survey that included instruments to measure emotional
responses.

Results

In total, 16% met the criteria for distress, 29.7% reported high anxiety
relating to the incident and 30.4% reported high anger. Perceptions that
strongly predicted these outcomes included feeling uncertain, being
unable to rule out harmful exposure, and believing that exposure would
have severe or hidden health effects or be difficult to detect. Using
information sources was associated with higher emotional outcome,
particularly for sources perceived to have low credibility.

Conclusions

Reducing uncertainty and improving the credibility of information is
essential in reducing the psychological impact of radiological
disasters.
Comprehensive Modulation of Tumor Progression and Regression with Periodic Fasting and Refeeding Circles via Boosting IGFBP-3 Loops and NK Responses
Authors: Chen Xiancheng , Lin Xiaojuan , Li Meng
Published: September 2012

Progressive tumor-bearing patients deserve to benefit from more realistic approaches. Here, a study revealed the impact of modified periodic fasting and refeeding regimen on tumor progression or regression with little or no loss of food intake and body weight. Human A549 lung, HepG-2 liver, and SKOV-3 ovary progressive tumor-bearing mice were established and subjected to 4 wk of periodic fasting/refeeding cycles (PFRC), including periodic 1-d fasting/6-d refeeding weekly (protocol 1) and periodic 2-d fasting/5-d refeeding weekly (P2DF/5DR, protocol 2), with ad libitum (AL)-fed hosts as controls. Afterwards, PFRC groups exhibited tumor growth arrest with some tendency towards regression; especially, complete regression of progressive tumors and metastases comprised between 43.75 and 56.25% of tumor-challenged hosts in P2DF/5DR group (P < 0.05). AL controls, in contrast, showed continuous tumor progression and metastasis. Finally, 100% hosts in P2DF/5DR and 62.5–68.75% in periodic 1-d fasting/6-d refeeding weekly groups survived a 4-month study period vs. only 31.25–37.5% in AL control group. Immunological assays and Luminex microarray revealed that tumor growth remission is mainly via natural killer cell (NK) reactivity and cross-regulation of IGF-binding protein-3, IGF/IGF-receptor, and megakaryocyte growth and development factor autocrine and paracrine loops. In vivo cellular and humoral assays indicated that tumor-regressive induction by PFRC protocols could be partly terminated by NK cell and IGF-binding protein-3 blockade or replenishment of IGF-I/-II and megakaryocyte growth and development factor. These findings offer a better understanding of comprehensive modulation of periodic fasting/refeeding strategy on the balance between tumor progression and regression.
INSL5-Deficient Mice Display an Alteration in Glucose Homeostasis and an Impaired Fertility
Authors: Burnicka-Turek Ozanna , Mohamed Belal A. , Shirneshan Katayoon , Thanasupawat Thatchawan , Hombach-Klonisch Sabine , Klonisch Thomas , Adham Ibrahim M.
Published: September 2012

Insulin-like factor 5 (INSL5), a member of the insulin superfamily, is expressed in the colorectum and hypothalamus. To facilitate studies into the role of INSL5, we generated Insl5−/− mice by gene targeting. Insl5−/− mice were born in the expected Mendelian ratio, reached normal body weight, but displayed impaired male and female fertility that are due to marked reduction in sperm motility and irregular length of the estrous cycle. Furthermore, Insl5−/− mice showed impairment in glucose homeostasis with characteristic elevation of serum glucose levels at an advanced age. Glucose and insulin tolerance tests revealed that the increased blood glucose in Insl5−/− mice was due to glucose intolerance resulting from reduced insulin secretion. Morphometric and immunohistological analyses revealed that the Insl5−/− mice had markedly reduced average islets area and β-cell numbers. Furthermore, immunohistochemistry showed the expression of INSL5 in enteroendocrine cells in the colorectal epithelium and the presence of its putative receptor relaxin family peptide receptor 4 in pancreatic islet cells. These results suggest the potential role of INSL5 signaling in the regulation of insulin secretion and β-cell homeostasis.
Rosiglitazone Promotes PPARγ-Dependent and -Independent Alterations in Gene Expression in Mouse Islets
Authors: Welters Hannah J. , El Ouaamari Abdelfattah , Kawamori Dan , Meyer John , Hu Jiang , Smith David M. , Kulkarni Rohit N.
Published: September 2012

The glitazone class of insulin-sensitizing agents act, in part, by the activation of peroxisome proliferator-activated receptor (PPAR)-γ in adipocytes. However, it is unclear whether the expression of PPARγ in the islets is essential for their potential β-cell-sparing properties. To investigate the in vivo effects of rosiglitazone on β-cell biology, we used an inducible, pancreatic and duodenal homeobox-1 enhancer element-driven, Cre recombinase to knockout PPARγ expression specifically in adult β-cells (PPARgKO). Subjecting the PPARgKO mice to a chow diet led to virtually undetectable changes in glucose or insulin sensitivity, which was paralleled by minimal changes in islet gene expression. Similarly, challenging the mutant mice with a high-fat diet and treatment with rosiglitazone did not alter insulin sensitivity, glucose-stimulated insulin secretion, islet size, or proliferation in the knockout mice despite PPARγ-dependent and -independent changes in islet gene expression. These data suggest that PPARγ expression in the β-cells is unlikely to be directly essential for normal β-cell function or the insulin-sensitizing actions of rosiglitazone.
Evidence for a Celiac Ganglion-Ovarian Kisspeptin Neural Network in the Rat: Intraovarian Anti-Kisspeptin Delays Vaginal Opening and Alters Estrous Cyclicity
Authors: Ricu Manuel A. , Ramirez Victor D. , Paredes Alfonso H. , Lara Hernan E.
Published: September 2012

Kisspeptin and its receptor GPR54 have been described as key hypothalamic components in the regulation of GnRH secretion. Kisspeptin is also present in several regions of the central nervous system and the peripheral organs and has recently been identified in the superior ganglion. Herein, we tested the possibility that ovarian kisspeptin is regulated by the sympathetic nervous system and participates locally in the regulation of ovarian function. Both ovarian and celiac ganglion kisspeptin mRNA levels increase during development, whereas kisspeptin peptide levels and plasma levels decrease during development. In the celiac ganglion, kisspeptin colocalized with tyrosine hydroxylase, indicating potential kisspeptin synthesis and transport within the sympathetic neurons. A continuous (64 h) cold stress induced marked changes within the kisspeptin neural system along the celiac ganglion-ovary axis. In vitro incubation with the β-adrenergic agonist isoproterenol increased ovarian kisspeptin mRNA and peptide levels, and this increase was inhibited by treatment with the β-antagonist propranolol. Sectioning the superior ovarian nerve altered the feedback information within the kisspeptin celiac ganglion-ovary axis. In vivo administration of a kisspeptin antagonist to the left ovarian bursa of 22- to 50-d-old unilaterally ovariectomized rats delayed the vaginal opening, decreased the percentage of estrous cyclicity, and decreased plasma, ovarian, and celiac ganglion kisspeptin concentrations but did not modify the LH plasma levels. These results indicate that the intraovarian kisspeptin system may be regulated by sympathetic nerve activity and that the peptide, either from a neural or ovarian origin, is required for proper coordinated ovarian function.
Neurochemical Characterization of Body Weight-Regulating Leptin Receptor Neurons in the Nucleus of the Solitary Tract
Authors: Garfield Alastair S. , Patterson Christa , Skora Susanne , Gribble Fiona M. , Reimann Frank , Evans Mark L. , Myers Martin G. , Heisler Lora K.
Published: September 2012

The action of peripherally released leptin at long-form leptin receptors (LepRb) within the brain represents a fundamental axis in the regulation of energy homeostasis and body weight. Efforts to delineate the neuronal mediators of leptin action have recently focused on extrahypothalamic populations and have revealed that leptin action within the nucleus of the solitary tract (NTS) is critical for normal appetite and body weight regulation. To elucidate the neuronal circuits that mediate leptin action within the NTS, we employed multiple transgenic reporter lines to characterize the neurochemical identity of LepRb-expressing NTS neurons. LepRb expression was not detected in energy balance-associated NTS neurons that express cocaine- and amphetamine-regulated transcript, brain-derived neurotrophic factor, neuropeptide Y, nesfatin, catecholamines, γ-aminobutyric acid, prolactin-releasing peptide, or nitric oxide synthase. The population of LepRb-expressing NTS neurons was comprised of subpopulations marked by a proopiomelanocortin-enhanced green fluorescent protein (EGFP) transgene and distinct populations that express proglucagon and/or cholecystokinin. The significance of leptin action on these three populations of NTS neurons was assessed in leptin-deficient Ob/Ob mice, revealing increased NTS proglucagon and cholecystokinin, but not proopiomelanocortin, expression. These data provide new insight into the appetitive brainstem circuits engaged by leptin.
Filamin A Is a Regulator of Blood-Testis Barrier Assembly during Postnatal Development in the Rat Testis
Authors: Su Wenhui , Mruk Dolores D. , Lie Pearl P. Y. , Lui Wing-yee , Cheng C. Yan
Published: September 2012

The blood-testis barrier (BTB) is an important ultrastructure in the testis. A delay in its assembly during postnatal development leads to meiotic arrest. Also, a disruption of the BTB by toxicants in adult rats leads to a failure in spermatogonial differentiation. However, the regulation of BTB assembly remains unknown. Herein, filamin A, an actin filament cross-linker that is known to maintain and regulate cytoskeleton structure and function in other epithelia, was shown to be highly expressed during the assembly of Sertoli cell BTB in vitro and postnatal development of BTB in vivo, perhaps being used to maintain the actin filament network at the BTB. A knockdown of filamin A by RNA interference was found to partially perturb the Sertoli cell tight junction (TJ) permeability barrier both in vitro and in vivo. Interestingly, this down-regulating effect on the TJ barrier function after the knockdown of filamin A was associated with a mis-localization of both TJ and basal ectoplasmic specialization proteins. Filamin A knockdown also induced a disorganization of the actin filament network in Sertoli cells in vitro and in vivo. Collectively, these findings illustrate that filamin A regulates BTB assembly by recruiting these proteins to the microenvironment in the seminiferous epithelium to serve as the building blocks. In short, filamin A participates in BTB assembly by regulating protein recruitment during postnatal development in the rat testis.
GPRC6A Mediates the Effects of l-Arginine on Insulin Secretion in Mouse Pancreatic Islets
Authors: Pi Min , Wu Yunpeng , Lenchik Nataliya I , Gerling Ivan , Quarles L. Darryl
Published: September 2012

l-Arginine (l-Arg) is an insulin secretagogue, but the molecular mechanism whereby it stimulates insulin secretion from β-cells is not known. The possibility that l-Arg regulates insulin secretion through a G protein-coupled receptor (GPCR)-mediated mechanism is suggested by the high expression of the nutrient receptor GPCR family C group 6 member A (GPRC6A) in the pancreas and TC-6 β-cells and the finding that Gprc6a−/]minus] mice have abnormalities in glucose homeostasis. To test the direct role of GPRC6A in regulating insulin secretion, we evaluated the response of pancreatic islets derived from Gprc6a−/]minus] mice to l-Arg. We found that the islet size and insulin content were decreased in pancreatic islets from Gprac6a−/]minus] mice. These alterations were selective for β-cells, because there were no abnormalities in serum glucagon levels or glucagon content of islets derived from Gprac6a−/]minus] mice. Significant reduction was observed in both the pancreatic ERK response to l-Arg administration to Gprc6a−/]minus] mice in vivo and l-Arg-induced insulin secretion and production ex vivo in islets isolated from Gprc6a−/]minus] mice. l-Arg stimulation of cAMP accumulation in isolated islets isolated from Gprc6a−/]minus] mice was also diminished. These findings suggest that l-Arg stimulation of insulin secretion in β-cells is mediated, at least in part, through GPRC6A activation of cAMP pathways.
Hepatic Insulin Signaling Changes: Possible Mechanism in Prenatal Hypoxia-Increased Susceptibility of Fatty Liver in Adulthood
Authors: Cao Li , Mao Caiping , Li Shigang , Zhang Yujuan , Lv Juanxiu , Jiang Shan , Xu Zhice
Published: September 2012

Nonalcoholic fatty liver disease (NAFLD) is strongly linked to insulin resistance. Prenatal hypoxia (PH) is a risk factor in programming of insulin resistance, glucose intolerance, and metabolic dysfunctions in later life, although the mechanisms are unclear. In this study, the role of metabolic and histological changes as well as the hepatic insulin signaling mechanisms were determined in increasing susceptibility of NAFLD in the fetus and offspring exposed to PH. Pregnant rats exposed to hypoxia (O2 10%) during pregnancy demonstrated decreased fetal body and liver weight as well as liver to body weight ratio, whereas these changes were not observed in the offspring. However, male liver to body weight ratio increased after PH stress. Microscopic analysis demonstrated that exposure to PH resulted in distorted architecture of the hepatic parenchyma cells with reduced cellularity in the fetus and offspring. Blood glucose and insulin levels were lower with enhanced insulin sensitivity and increased expression of hepatic insulin-signaling elements in the fetus. Furthermore, insulin resistance, impaired glucose homeostasis, and altered expression of insulin-signaling elements occurred in the offspring. Postnatal hypoxia increased hepatic lipid droplets and triglyceride in liver, whereas expressions of insulin-signaling elements were less in the offspring exposed to PH except glucose transporters 2. The results indicated that PH contributed to hepatocyte heteroplasia and metabolic changes that enhanced vulnerability for NAFLD in the offspring, probably via affecting insulin signaling pathway, including glucose transporters 2.
Gonadotrope Plasticity at Cellular and Population Levels
Authors: Alim Zahara , Hartshorn Cheryl , Mai Oliver , Stitt Iain , Clay Colin , Tobet Stuart , Boehm Ulrich
Published: September 2012

Hormone-secreting cells within the anterior pituitary gland may form organized and interdigitated networks that adapt to changing endocrine conditions in different physiological contexts. For gonadotropes, this might reflect a strategy to cope with acute changes throughout different female reproductive stages. The current study examined gonadotropes in female mice at characteristically different hormonal stages: prepubertal, postpubertal, and lactating. Gonadotrope plasticity was examined at the level of the whole population and single cells at different stages by imaging both fixed and live pituitary slices. The use of a model animal providing for the identification of selectively fluorescent gonadotropes allowed the particular advantage of defining cellular plasticity specifically for gonadotropes. In vivo analyses of gonadotropes relative to vasculature showed significantly different gonadotrope distributions across physiological states. Video microscopy studies using live slices ex vivo demonstrated pituitary cell plasticity in the form of movements and protrusions in response to GnRH. As positive feedback from rising estradiol levels is important for priming the anterior pituitary gland for the LH surge, experiments provide evidence of estradiol effects on GnRH signaling in gonadotropes. The experiments presented herein provide new insight into potential plasticity of gonadotropes within the anterior pituitary glands of female mice.
The Effects of Long-Term Treatment with Estradiol and Medroxyprogesterone Acetate on Tyrosine Hydroxylase Fibers and Neuron Number in the Medial Prefrontal Cortex of Aged Female Rats
Authors: Chisholm Nioka C. , Packard Alexandria R. , Koss Wendy A. , Juraska Janice M.
Published: September 2012

Menopausal women often initiate hormone treatment to alleviate the symptoms of menopause. Research suggests that these treatments also affect cognition, and studies in young animals indicate that hormone treatment can alter several neuroanatomical measures. However, very little is known about the effects of long-term hormone treatment on the aging female brain. This study investigated the effects of hormone treatment on neuron number and tyrosine hydroxylase (TH) in the rat medial prefrontal cortex (mPFC). Female Long Evans rats were ovariectomized at middle age (12–13 months) and placed in one of four groups: no replacement (NR) (n = 12), 17β-estradiol (E2) (n = 12), E2 and progesterone (n = 7), or E2 and medroxyprogesterone acetate (MPA) (n = 10). Animals were euthanized at 20 months, and the brains were Nissl stained; a subset was immunostained for TH [NR (n = 5); E2 (n = 6); E2 + MPA (n = 4); E2 + progesterone (n = 6)]. E2 was administered through the drinking water, and progestagens were administered via pellets inserted at the nape of the neck. Neuron number and TH fiber density were quantified in the mPFC. Hormone treatment did not alter neuron number. Treatment with E2 and MPA resulted in greater TH densities than NR in layer 1 (P < 0.05). In layers 2/3, animals receiving E2 had greater TH densities than NR animals (P < 0.01). These results indicate that long-term hormone treatments alter dopaminergic fibers and potentially the functioning of the aging mPFC.
Hypoxia Induces Autophagy in Primary Human Trophoblasts
Authors: Chen Baosheng , Longtine Mark S. , Nelson D. Michael
Published: September 2012

Autophagy is a highly regulated and dynamic process that maintains cellular homeostasis and plays a prosurvival role in most cells. Although hypoxia has been shown to induce apoptosis in placental trophoblasts, the hypoxic effect on autophagy has not been studied. We hypothesized that autophagy plays a prosurvival role in the placental trophoblasts by antagonizing hypoxia-induced apoptosis. Our data show that the expression of Light chain 3-II (LC3-II), an autophagic marker and cleaved poly(ADP-ribose) polymerase, an apoptosis marker, are inversely related in cultured trophoblasts. Exposure to rapamycin or hypoxia inactivated mammalian target of rapamycin, as reflected by reduced phosphorylation of ribosomal protein S6, indicating that mammalian target of rapamycin regulates autophagy in cultured cytotrophoblasts. Bafilomycin prevented the degradation of cargo and increased LC3-II and p62 in cytotrophoblasts exposed to hypoxia, revealing enhanced autophagic flux. Importantly, bafilomycin enhanced expression of autophagy-related protein 7 (Atg7), parallel to the increased apoptosis measured by cleaved poly(ADP-ribose) polymerase. LY294002, a phosphatidylinositol 3-kinase inhibitor, increased apoptosis in the trophoblasts under hypoxia or standard conditions. Silencing of Atg7 decreased both apoptosis and LC3-II in the trophoblasts, suggesting a dual role of Atg7 in both autophagy and apoptosis. We conclude that there is a cross talk between autophagy and apoptosis in the placental trophoblasts; autophagy plays a prosurvival role and Atg7 has roles in both autophagy and apoptosis under hypoxia.
Task3 Potassium Channel Gene Invalidation Causes Low Renin and Salt-Sensitive Arterial Hypertension
Authors: Penton David , Bandulik Sascha , Schweda Frank , Haubs Sophia , Tauber Philipp , Reichold Markus , Cong Lu Dang , El Wakil Abeer , Budde Thomas , Lesage Florian , Lalli Enzo , Zennaro Maria-Christina , Warth Richard , Barhanin Jacques
Published: September 2012

Task1 and Task3 potassium channels (Task: tandem of P domains in a weak inward rectifying K+ channel-related acid-sensitive K+ channel) are believed to control the membrane voltage of aldosterone-producing adrenal glomerulosa cells. This study aimed at understanding the role of Task3 for the control of aldosterone secretion. The adrenal phenotype of Task3−/− mice was investigated using electrophysiology, adrenal slices, and blood pressure measurements. Primary adrenocortical cells of Task3−/− mice were strongly depolarized compared with wild-type (−52 vs. −79 mV), and in fresh adrenal slices Ca2+ signaling of Task3−/− glomerulosa cells was abnormal. In living Task3−/− mice, the regulation of aldosterone secretion showed specific deficits: Under low Na+ and high K+ diets, protocols known to increase aldosterone, and under standard diet, Task3 inactivation was compensated and aldosterone was normal. However, high Na+ and low K+ diets, two protocols known to lower aldosterone, failed to lower aldosterone in Task3−/− mice. The physiological regulation of aldosterone was disturbed: aldosterone-renin ratio, an indicator of autonomous aldosterone secretion, was 3-fold elevated at standard and high Na+ diets. Isolated adrenal glands of Task3−/− produced 2-fold more aldosterone. As a consequence, Task3−/− mice showed salt-sensitive arterial hypertension (plus 10 mm Hg). In conclusion, Task3 plays an important role in the adaptation of aldosterone secretion to dietary salt intake.
Increased Neurokinin B (Tac2) Expression in the Mouse Arcuate Nucleus Is an Early Marker of Pubertal Onset with Differential Sensitivity to Sex Steroid-Negative Feedback than Kiss1
Authors: Gill John C. , Navarro Víctor M. , Kwong Cecilia , Noel Sekoni D. , Martin Cecilia , Xu Shuyun , Clifton Donald K. , Carroll Rona S. , Steiner Robert A. , Kaiser Ursula B.
Published: September 2012

At puberty, neurokinin B (NKB) and kisspeptin (Kiss1) may help to amplify GnRH secretion, but their precise roles remain ambiguous. We tested the hypothesis that NKB and Kiss1 are induced as a function of pubertal development, independently of the prevailing sex steroid milieu. We found that levels of Kiss1 mRNA in the arcuate nucleus (ARC) are increased prior to the age of puberty in GnRH/sex steroid-deficient hpg mice, yet levels of Kiss1 mRNA in wild-type mice remained constant, suggesting that sex steroids exert a negative feedback effect on Kiss1 expression early in development and across puberty. In contrast, levels of Tac2 mRNA, encoding NKB, and its receptor (NK3R; encoded by Tacr3) increased as a function of puberty in both wild-type and hpg mice, suggesting that during development Tac2 is less sensitive to sex steroid-dependent negative feedback than Kiss1. To compare the relative responsiveness of Tac2 and Kiss1 to the negative feedback effects of gonadal steroids, we examined the effect of estradiol (E2) on Tac2 and Kiss1 mRNA and found that Kiss1 gene expression was more sensitive than Tac2 to E2-induced inhibition at both juvenile and adult ages. This differential estrogen sensitivity was tested in vivo by the administration of E2. Low levels of E2 significantly suppressed Kiss1 expression in the ARC, whereas Tac2 suppression required higher E2 levels, supporting differential sensitivity to E2. Finally, to determine whether inhibition of NKB/NK3R signaling would block the onset of puberty, we administered an NK3R antagonist to prepubertal (before postnatal d 30) females and found no effect on markers of pubertal onset in either WT or hpg mice. These results indicate that the expression of Tac2 and Tacr3 in the ARC are markers of pubertal activation but that increased NKB/NK3R signaling alone is insufficient to trigger the onset of puberty in the mouse.