Claudin-1 as a novel target gene induced in obesity and associated to inflammation, fibrosis, and cell differentiation.

OBJECTIVE: T lymphocytes from visceral and subcutaneous white adipose tissues (vWAT and sWAT, respectively) can have opposing roles in the systemic metabolic changes associated with obesity. However, few studies have focused on this subject. Claudin-1 (CLDN1) is a protein involved canonically in tight junctions and tissue paracellular permeability. We evaluated T-lymphocyte gene expression in vWAT and sWAT and in the whole adipose depots in human samples. METHODS: A Clariom D-based transcriptomic analysis was performed on T lymphocytes magnetically separated from vWAT and sWAT from patients with obesity (Cohort 1; N = 11). Expression of candidate genes resulting from that analysis was determined in whole WAT from individuals with and without obesity (Cohort 2; patients with obesity: N = 13; patients without obesity: N = 14). RESULTS: We observed transcriptional differences between T lymphocytes from sWAT compared with vWAT. Specifically, CLDN1 expression was found to be dramatically induced in vWAT T cells relative to those isolated from sWAT in patients with obesity. CLDN1 was also induced in obesity in vWAT and its expression correlates with genes involved in inflammation, fibrosis, and adipogenesis. CONCLUSION: These results suggest that CLDN1 is a novel marker induced in obesity and differentially expressed in T lymphocytes infiltrated in human vWAT as compared with sWAT. This protein may have a crucial role in the crosstalk between T lymphocytes and other adipose tissue cells and may contribute to inflammation, fibrosis, and alter homeostasis and promote metabolic disease in obesity.

Pleiotrophin Deficiency Induces Browning of Periovarian Adipose Tissue and Protects against High-Fat Diet-Induced Hepatic Steatosis.

(1) Background: Pleiotrophin preserves insulin sensitivity, regulates adipose tissue lipid turnover and plasticity, energy metabolism and thermogenesis. The aim of this study was to determine the role of pleiotrophin in hepatic lipid metabolism and in the metabolic crosstalk between the liver and brown and white adipose tissue (AT) in a high-fat diet-induced (HFD) obesity mice model. (2) Methods: We analyzed circulating variables, lipid metabolism (hepatic lipid content and mRNA expression), brown AT thermogenesis (UCP-1 expression) and periovarian AT browning (brown adipocyte markers mRNA and immunodetection) in Ptn-/- mice either fed with standard-chow diet or with HFD and in their corresponding Ptn+/+ counterparts. (3) Results: HFD-Ptn-/- mice are protected against the development of HFD-induced insulin resistance, had lower liver lipid content and lower expression of the key enzymes involved in triacylglycerides and fatty acid synthesis in liver. HFD-Ptn-/- mice showed higher UCP-1 expression in brown AT. Moreover, Ptn deletion increased the expression of specific markers of brown/beige adipocytes and was associated with the immunodetection of UCP-1 enriched multilocular adipocytes in periovarian AT. (4) Conclusions: Ptn deletion protects against the development of HFD-induced insulin resistance and liver steatosis, by increasing UCP-1 expression in brown AT and promoting periovarian AT browning.

Recomendaciones para el uso de la hormona de crecimiento humana recombinante en pacientes pediátricos de talla baja en Colombia / Recommendations for treatment with recombinant human growth hormone in pediatric patients in Colombia

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Abstract In Colombia there are no guidelines for diagnosis and management of patients with short stature and for the use of recombinant human growth hormone, mainly caused by the diversity of training centers in pediatric endocrinology. In response to this situation, the Asociación Colegio Colombiana de Endocrinología Pediátrica leds the first colombian short stature expert committee in order to standardize the use of human recombinant growth hormone. This work had the participation and endorsement of a consortium of clinical experts representing the Sociedad Colombiana de Pediatría, Secretaría Distrital de Salud de Bogotá- Subred Integrada de Servicios de Salud Suroccidente, Fundación Universitaria Sanitas, Universidad de los Andes and some public and private health institutions in the country, in addition to the participation of methodological experts from the Instituto Global de Excelencia Clínica Keralty. By reviewing the literature and with the best available evidence, we proposed to unify definitions, a diagnostic algorithm, biochemical and dynamic tests with their reference parameters, a description of the considerations about growth hormone use among the indications approved by regulatory agency for medications and food in Colombia and finally a proposal for an informed consent and a medication fact sheet available for parents and patients.

Community Engagement and Planning versus Resources for Services for Implementing Depression Quality Improvement: Exploratory Analysis for Black and Latino Adults.

Objective: Racial/ethnic minorities experience disparities in depression1 and there is a paucity of evidence-based interventions to improve depression care access and outcomes. Community Partners in Care (CPIC) is a community-partnered study of depression care quality improvement (QI) in under-resourced, urban communities: Community Engagement and Planning (CEP) for multi-sector coalitions, and Resources for Services (RS) for program technical assistance.2 CEP demonstrated benefits for the overall CPIC study population; effects for Black and Latino sub-populations are unknown. Methods: This sub-analysis examines outcomes for 409 Latino and 488 Black (non-Latino) adults recruited from 90 programs who completed baseline or 6-month follow-up. Regression analyses were used to estimate CEP vs RS intervention effects on primary (Mental Health Related Quality of Life [MHRQL], Patient Health Questionnaire-9 [PHQ-9]) and community-prioritized (mental wellness, physical activity, risk for homelessness) outcomes at 6-months. Results: Baseline characteristics did not differ significantly by intervention in either group. In the adjusted analysis for Black adults, CEP resulted in decreased odds of poor MHRQL (OR: .62, 95% CI=.41-.94, P=.028) with a trend for reducing homelessness risk (OR: .60, .35-1.05, P=.69). For Latino adults, CEP resulted in greater probability of mental wellness (OR: 1.81, 1.05-3.13, P=.034) and a trend for increased physical activity (OR: 1.52, .93-2.49, P=.091). Conclusions: Exploratory analyses of CEP for depression quality improvement suggests significant 6-month benefits in mental health outcomes for Black and Latino participants and trends for improvement in community-prioritized outcomes for both groups. Findings may inform research in multi-sector coalitions to promote equity in depression care.

Community Partners in Care: 6- and 12-month Outcomes of Community Engagement versus Technical Assistance to Implement Depression Collaborative Care among Depressed Older Adults.

Objective: Community Partners in Care, a community-partnered, cluster-randomized trial with depressed clients from 95 Los Angeles health and community programs, examined the added value of a community coalition approach (Community Engagement and Planning [CEP]) versus individual program technical assistance (Resources for Services [RS]) to implement depression collaborative care in underserved communities. This exploratory subanalysis examines 6- and 12-month outcomes among CPIC participants aged >50 years. Design: Community-partnered, cluster-randomized trial conducted between April 2010 and March 2012. Setting: Hollywood-Metropolitan (HM) and South Los Angeles (SLA) Service Planning Areas (SPAs), Los Angeles, California. Participants: 394 participants aged >50 years with depressive symptoms (8-item Patient Health Questionnaire score ≥ 10). Intervention: A community-partnered multi-sector coalition approach (Community Engagement and Planning [CEP]) vs individual program technical assistance (Resources for Services [RS]) to implement depression collaborative care. Main Outcome Measures: Depressive symptoms (PHQ-8 score), mental health-related quality of life (MHRQL), community-prioritized outcomes including mental wellness, homelessness risk and physical activity, and services utilization. Results: At 6 months, CEP was more effective than RS at improving MHRQL and mental wellness among participants aged >50 years; no differences were found in the effects of CEP vs RS on other outcomes. No significant outcome differences between CEP and RS were found at 12 months. Conclusions: A multisector community coalition approach may offer additional benefits over individual program technical assistance to improve outcomes among depressed adults aged >50 years living in underserved communities.

Engaging African American Veterans with Health Care Access Challenges in a Community Partnered Care Coordination Initiative: A Qualitative Needs Assessment.

Background: Little has been written about engaging potentially eligible members of a health care system who are not accessing the care to which they are entitled. Knowing more about the experiences of African American Veterans who regularly experience health care access challenges may be an important step toward equitable, coordinated Veterans Health Administration (VHA) care. This article explores the experiences of African American Veterans who are at risk of experiencing poor care coordination. Design: We partnered with a community organization to recruit and engage Veterans in three exploratory engagement workshops between October 2015 and February 2016. Participants and Setting: Veterans living in South Los Angeles, California. Main Outcome Measures: Veterans were asked to describe their experiences with community care and the VHA, a division of the US Department of Veterans Affairs (VA). Field notes taken during the workshops were analyzed by community and academic partners using grounded theory methodology to identify emergent themes. Results: 12 Veterans and 3 family members of Veterans participated in one or more engagement workshops. Their trust in the VA was generally low. Positive themes included: Veterans have knowledge to share and want to help other Veterans; and connecting to VA services can result in positive experiences. Negative themes included: functional barriers to accessing VA health care services; insensitive VA health care environment; lack of trust in the VA health care system; and Veteran status as disadvantageous for accessing non-VA community services. Conclusions: Veterans living in underserved areas who have had difficulty accessing VA care have unique perspectives on VA services. Partnering with trusted local community organizations to engage Veterans in their home communities is a promising strategy to inform efforts to improve care access and coordination for vulnerable Veterans.

Surviving Depression: Clinical Qualitative Analysis of Long-Term Survival for Ethnically Diverse, Depressed Patients.

Depression is persistent and recurrent across ethnic groups. Few narrative analyses of long-term outcomes for ethnically diverse adults with depression exist. We combined 9 years of quantitative data, qualitative interviews at 10 years, clinician ratings of outcomes, and a community discussion group with the objective of describing long-term recovery and survival of diverse primary care patients after an episode of depression. Nearly half of participants were found to be depressed at some time over a 10-year period, and most cases across ethnic groups were judged to need further treatment. The ethnically diverse community members that analyzed the transcripts emphasized assets that participants showed in surviving multiple life stresses. Different sex and ethnic/racial groups had different characteristics of engaging in care, with Latino women in particular raising concerns about care engagement, coping with stress, and long-term outcomes.

Grandparenting experiences among adults with a history of depression: a mixed-methods study.

OBJECTIVE: Grandparenting is an important social role, but how adults with a history of depression experience grandparenting is unknown; we describe grandparenting experiences reported by an ethnically diverse sample of adults with a history of depression. METHOD: Mixed-methods study using semistructured interviews of adults at 10-year follow-up and quantitative data collected over 9 years from 280 systematically sampled participants from a longitudinal, multisite trial of quality-improvement interventions for depressed primary care patients; of 280, 110 reported noncustodial grandparenting experiences. RESULTS: Of 110 adults reporting grandparenting experiences, 90 (82%) reported any positive experience such as special joy; 57 (52%) reported any stressful experience such as separation; and 27 (34%) reported mixed experiences. Adults with chronic or recent depression were significantly more likely than their respective counterparts to report any stressful experience (P<0.05). There was no significant association between depression status and reporting a positive experience. CONCLUSION(S): Grandparenting was a highly salient and positive experience as reported by ethnically diverse adults 10 years after being identified as depressed in primary care. Depression status was associated with reporting stressful but not positive experiences. Specific themes underlying positive and stressful experiences may have implications for developing strategies to enhance quality of life for adults with a history of depression who are grandparents.

Older depressed Latinos' experiences with primary care visits for personal, emotional and/or mental health problems: a qualitative analysis.

OBJECTIVE: To describe salient experiences with a primary care visit (eg, the context leading up to the visit, the experience and/or outcomes of that visit) for emotional, personal and/or mental health problems older Latinos with a history of depression and recent depressive symptoms and/or antidepressant medication use reported 10 years after enrollment into a randomized controlled trial of quality-improvement for depression in primary care. DESIGN: Secondary analysis of existing qualitative data from the second stage of the continuation study of Partners in Care (PIC). PARTICIPANTS: Latino ethnicity, aged > or =50 years, recent depressive symptoms and/or antidepressant medication use, and a recent primary care visit for mental health problems. Of 280 second-stage participants, 47 were eligible. Both stages of the continuation study included participants from the PIC parent study control and 2 intervention groups, and all had a history of depression. METHODS: Data analyzed by a multidisciplinary team using grounded theory methodology. RESULTS: Five themes were identified: beliefs about the nature of depression; prior experiences with mental health disorders/treatments; sociocultural context (eg, social relationships, caregiving, the media); clinic-related features (eg, accessibility of providers, staff continuity, amount of visit time); and provider attributes (eg, interpersonal skills, holistic care approach). CONCLUSIONS: Findings emphasize the importance of key features for shaping the context leading up to primary care visits for help-seeking for mental health problems, and the experience and/or outcomes of those visits, among older depressed Latinos at long-term follow-up, and may help tailor chronic depression care for the clinical management of this vulnerable population.

Novel role of parathyroid hormone-related protein in the pathophysiology of the diabetic kidney: evidence from experimental and human diabetic nephropathy.

Parathyroid hormone-related protein (PTHrP) and its receptor type 1 (PTH1R) are extensively expressed in the kidney, where they are able to modulate renal function. Renal PTHrP is known to be overexpressed in acute renal injury. Recently, we hypothesized that PTHrP involvement in the mechanisms of renal injury might not be limited to conditions with predominant damage of the renal tubulointerstitium and might be extended to glomerular diseases, such as diabetic nephropathy (DN). In experimental DN, the overexpression of both PTHrP and the PTH1R contributes to the development of renal hypertrophy as well as proteinuria. More recent data have shown, for the first time, that PTHrP is upregulated in the kidney from patients with DN. Collectively, animal and human studies have shown that PTHrP acts as an important mediator of diabetic renal cell hypertrophy by a mechanism which involves the modulation of cell cycle regulatory proteins and TGF- ß 1. Furthermore, angiotensin II (Ang II), a critical factor in the progression of renal injury, appears to be responsible for PTHrP upregulation in these conditions. These findings provide novel insights into the well-known protective effects of Ang II antagonists in renal diseases, paving the way for new therapeutic approaches.

Accelerated renal disease is associated with the development of metabolic syndrome in a glucolipotoxic mouse model.

Individuals with metabolic syndrome are at high risk of developing chronic kidney disease (CKD) through unclear pathogenic mechanisms. Obesity and diabetes are known to induce glucolipotoxic effects in metabolically relevant organs. However, the pathogenic role of glucolipotoxicity in the aetiology of diabetic nephropathy is debated. We generated a murine model, the POKO mouse, obtained by crossing the peroxisome proliferator-activated receptor gamma 2 (PPARγ2) knockout (KO) mouse into a genetically obese ob/ob background. We have previously shown that the POKO mice showed: hyperphagia, insulin resistance, hyperglycaemia and dyslipidaemia as early as 4 weeks of age, and developed a complete loss of normal ß-cell function by 16 weeks of age. Metabolic phenotyping of the POKO model has led to investigation of the structural and functional changes in the kidney and changes in blood pressure in these mice. Here we demonstrate that the POKO mouse is a model of renal disease that is accelerated by high levels of glucose and lipid accumulation. Similar to ob/ob mice, at 4 weeks of age these animals exhibited an increased urinary albumin:creatinine ratio and significantly increased blood pressure, but in contrast showed a significant increase in the renal hypertrophy index and an associated increase in p27(Kip1) expression compared with their obese littermates. Moreover, at 4 weeks of age POKO mice showed insulin resistance, an alteration of lipid metabolism and glomeruli damage associated with increased transforming growth factor beta (TGFß) and parathyroid hormone-related protein (PTHrP) expression. At this age, levels of proinflammatory molecules, such as monocyte chemoattractant protein-1 (MCP-1), and fibrotic factors were also increased at the glomerular level compared with levels in ob/ob mice. At 12 weeks of age, renal damage was fully established. These data suggest an accelerated lesion through glucolipotoxic effects in the renal pathogenesis in POKO mice.

Parathyroid hormone-related protein is a hypertrophy factor for human mesangial cells: Implications for diabetic nephropathy.

Hypertrophy of human mesangial cells (HMC) is among the earliest characteristics in patients with diabetic nephropathy (DN). Recently, we observed the upregulation of parathyroid hormone (PTH)-related protein (PTHrP) in experimental DN, associated with renal hypertrophy. Herein, we first examined whether PTHrP was overexpressed in human DN, and next assessed the putative role of this protein on high glucose (HG)-induced HMC hypertrophy. As previously found in mice, kidneys from diabetic patients showed an increased tubular and glomerular immunostaining for PTHrP. In HMC, HG medium increased PTHrP protein expression associated with the development of hypertrophy as assessed by cell protein content. This effect was also induced by PTHrP(1-36). HG and PTHrP(1-36)-induced hypertrophy were associated with an increase in cyclin D1 and p27Kip1 protein expression, a decreased cyclin E expression, and the prevention of cyclin E/cdk2 complex activation. Both PTHrP neutralizing antiserum (α-PTHrP) and the PTH/PTHrP receptor antagonist (JB4250) were able to abolish HG induction of hypertrophy, the aforementioned changes in cell cycle proteins, and also TGF-ß1 up-regulation. Moreover, the capability of both HG and PTHrP(1-36) to induce HMC hypertrophy was abolished by α-TGFß1. These data show for the first time that PTHrP is upregulated in the kidney of patients with DN. Our findings also demonstrate that PTHrP acts as an important mediator of HG-induced HMC hypertrophy by modulating cell cycle regulatory proteins and TGF-ß1.

A transgenic mouse model for studying the role of the parathyroid hormone-related protein system in renal injury.

Parathyroid hormone- (PTH-) related protein (PTHrP) and its receptor, the PTH1 receptor (PTH1R), are widely expressed in the kidney, where PTHrP exerts a modulatory action on renal function. PTHrP is known to be upregulated in several experimental nephropathies such as acute renal failure (ARF), obstructive nephropathy (ON) as well as diabetic nephropathy (DN). In this paper, we will discuss the functional consequences of chronic PTHrP overexpression in the damaged kidney using a transgenic mouse strain overexpressing PTHrP in the renal proximal tubule. In both ARF and ON, PTHrP displays proinflammatory and profibrogenic actions including the induction of epithelia to mesenquima transition. Moreover, PTHrP participates in the mechanisms of renal hypertrophy as well as proteinuria in experimental DN. Angiotensin II (Ang II), a critical factor in the progression of renal injury, appears to be, at least in part, responsible for endogenous PTHrP upregulation in these pathophysiological settings. These findings provide novel insights into the well-known protective effects of Ang II antagonists in renal diseases, paving the way for new therapeutic approaches.

Early peroxisome proliferator-activated receptor gamma regulated genes involved in expansion of pancreatic beta cell mass.

BACKGROUND: The progression towards type 2 diabetes depends on the allostatic response of pancreatic beta cells to synthesise and secrete enough insulin to compensate for insulin resistance. The endocrine pancreas is a plastic tissue able to expand or regress in response to the requirements imposed by physiological and pathophysiological states associated to insulin resistance such as pregnancy, obesity or ageing, but the mechanisms mediating beta cell mass expansion in these scenarios are not well defined. We have recently shown that ob/ob mice with genetic ablation of PPARγ2, a mouse model known as the POKO mouse failed to expand its beta cell mass. This phenotype contrasted with the appropriate expansion of the beta cell mass observed in their obese littermate ob/ob mice. Thus, comparison of these models islets particularly at early ages could provide some new insights on early PPARγ dependent transcriptional responses involved in the process of beta cell mass expansion RESULTS: Here we have investigated PPARγ dependent transcriptional responses occurring during the early stages of beta cell adaptation to insulin resistance in wild type, ob/ob, PPARγ2 KO and POKO mice. We have identified genes known to regulate both the rate of proliferation and the survival signals of beta cells. Moreover we have also identified new pathways induced in ob/ob islets that remained unchanged in POKO islets, suggesting an important role for PPARγ in maintenance/activation of mechanisms essential for the continued function of the beta cell. CONCLUSIONS: Our data suggest that the expansion of beta cell mass observed in ob/ob islets is associated with the activation of an immune response that fails to occur in POKO islets. We have also indentified other PPARγ dependent differentially regulated pathways including cholesterol biosynthesis, apoptosis through TGF-ß signaling and decreased oxidative phosphorylation.

Parathyroid hormone-related protein induces hypertrophy in podocytes via TGF-beta(1) and p27(Kip1): implications for diabetic nephropathy.

BACKGROUND: Hypertrophy of podocytes is characteristic in diabetic nephropathy (DN). Previously, we observed the upregulation of parathyroid hormone-related protein (PTHrP) and its receptor PTH1R, in experimental DN, associated with renal hypertrophy. Herein, we test the hypothesis that PTHrP participates in the mechanism of high glucose (HG)-induced podocyte hypertrophy. METHODS: On mouse podocytes, hypertrophy was assessed by protein content/cell and [H(3)]leucine incorporation. Podocytes were stimulated with HG (25 mM), PTHrP(1-36) (100 nM), angiotensin II (AngII) (100 nM) or TGF-beta(1) (5 ng/mL) in the presence or absence of PTHrP-neutralizing antibodies (alpha-PTHrP), the PTH1R antagonist JB4250 (10 microM), PTHrP silencer RNA (siRNA) or TGF-beta(1) siRNA. Protein expression was analysed by western blot and immunohistochemistry. RESULTS: HG-induced hypertrophy was abolished in the presence of either alpha-PTHrP or PTHrP siRNA. This effect was associated with an inhibition of the upregulation of TGF-beta(1) and p27(Kip1). JB4250 also inhibited HG-induced p27(Kip1) upregulation. Interestingly, whilst HG and AngII were unable to stimulate the expression of p27(Kip1) on PTHrP siRNA-transfected podocytes, TGF-beta(1) was still able to upregulate p27(Kip1) in these cells. Moreover, HG and PTHrP-induced hypertrophy as well as p27(Kip1) upregulation were abolished on TGF-beta(1) siRNA-transfected podocytes. Furthermore, the glomeruli of transgenic PTHrP-overexpressing mice showed a constitutive overexpression of TGF-beta(1) and p27(Kip1) to a degree similar to that of diabetic animals. CONCLUSIONS: PTHrP seems to participate in the hypertrophic signalling triggered by HG. In this condition, AngII induces the upregulation of PTHrP, which might induce the expression of TGF-beta(1) and p27(Kip1). These findings provide new insights into the protective effects of AngII antagonists in DN, opening new paths for intervention.

Entraining synthetic genetic oscillators.

We propose a new approach for synchronizing a population of synthetic genetic oscillators, which consists in the entrainment of a colony of repressilators by external modulation. We present a model where the repressilator dynamics is affected by periodic changes in temperature. We introduce an additional plasmid in the bacteria in order to correlate the temperature variations with the enhancement of the transcription rate of a certain gene. This can be done by introducing a promoter that is related to the heat shock response. This way, the expression of that gene results in a protein that enhances the overall oscillations. Numerical results show coherent oscillations of the population for a certain range of the external frequency, which is in turn related to the natural oscillation frequency of the modified repressilator. Finally we study the transient times related with the loss of synchronization and we discuss possible applications in biotechnology of large-scale production coupled to synchronization events induced by heat shock.

Baseline dimensions of the human vagina.

BACKGROUND: Vaginal anatomy has been poorly studied. This study aimed to measure baseline dimensions of the undistended vagina of women of reproductive age. METHODS: We combined baseline information collected from five clinical trials using magnetic resonance imaging (MRI) to quantify distribution of a vaginal gel. Seventy-seven MRI scans were performed on 28 women before gel application to establish baseline vaginal measurements. Average dimensions were calculated for each woman and for the population. The influence of potential covariates (age, height, weight and parity) on these dimensions was assessed. RESULTS: MRI measurements are reproducible. The SD surrounding the mean at each anatomical site, and with summary measurements, was significantly smaller with each subject compared with the population. Mean vaginal length from cervix to introitus was 62.7 mm. Vaginal width was largest in the proximal vagina (32.5 mm), decreased as it passed through the pelvic diaphragm (27.8 mm) and smallest at the introitus (26.2 mm). Significant positive associations were parity with vaginal fornix length, age with pelvic flexure width and the height with width at the pelvic flexure. CONCLUSION: No one description characterized the shape of the human vagina. Although there is variation among women, variables such as parity, age and height are positively associated with differences in baseline dimensions.

Role of the renin-angiotensin system on the parathyroid hormone-related protein overexpression induced by nephrotoxic acute renal failure in the rat.

Parathyroid hormone-related protein (PTHrP), a mitogenic factor for renal cells, is overexpressed in acute renal failure (ARF). Recent data support an association between PTHrP and the renin-angiotensin system in the damaged kidney. The effects of angiotensin II (Ang II) inhibitors (quinapril, enalapril, and/or losartan) on PTHrP and the PTH1 receptor (PTH1R) expression in rats with either folic acid (FA)- or gentamicin-induced ARF were analyzed. The decreased renal function and the PTHrP upregulation and PTH1R downregulation induced by the nephrotoxins were inhibited by the Ang II blockers. In tubuloepithelial cells NRK-52E, the rapid (10 min) increase in PTHrP mRNA by FA, associated with a perinuclear relocalization of Ang II/AT1 receptor, was inhibited by losartan but not candesartan, which traps Ang II receptors at the cell surface. Maximal PTHrP protein overexpression by FA (at 24 to 72 h)-or by exogenous Ang II-was abolished by both Ang II antagonists. PTHrP upregulation by FA was preceded by increased extracellular signal-regulated kinase (ERK) phosphorylation and inhibited by the ERK inhibitor PD098059. FA also activated cAMP response element-binding (CREB) protein, and this was prevented by losartan in these cells. Moreover, PTHrP mRNA overexpression by either FA or Ang II occurred in NRK 52E that were transfected with a CREB construct but not the dominant-negative CREB133 construct. These findings demonstrate that the decreased renal function and PTHrP overexpression in nephrotoxin-damaged kidney depends on renin-angiotensin system. In this setting, intracellular Ang II/AT1 receptor recycling seems to be related to PTHrP induction through ERK and CREB activation in tubuloepithelial cells.

Expression of functionally active cannabinoid receptor CB1 in the human prostate gland.

BACKGROUND: Cannabinoids exert a wide spectrum of effects in men including alterations in the reproductive system. To date, two types of cannabinoid receptors have been cloned in humans, namely CB(1) and CB(2) belonging to the G protein-coupled receptor superfamily. Although cannabinoids have functional and morphologic effects in the prostate gland, the expression of cannabinoid receptors in this tissue has never been investigated. The aim of this study was to analyze the expression of cannabinoid receptors in the human prostate gland and their regulatory effects on adenylyl cyclase activity. METHODS: To investigate the existence of cannabinoid receptors in prostate, we used various methods, including reverse transcriptase-polymerase chain reaction, Western blotting, and immunohistochemistry. Adenylyl cyclase activity was analyzed by measuring the cAMP produced by means of a competitive assay by using PKA. RESULTS: Both mRNA for CB(1) and the corresponding protein are expressed in the human prostate gland at a level comparable with the receptor expressed in cerebellum. The molecular mass of the protein estimated from Western blot analysis was 58 kDa, which is in concordance with previous data for CB(1) in other tissues. Immunohistochemical studies show that CB(1) is preferentially expressed in the epithelia of the prostate. The cannabinoid receptor expressed in the prostate negatively regulates adenylyl cyclase activity through a pertussis toxin-sensitive protein.