Comparative expression profile of CD10 and cyclin D1 in cutaneous histiocytofibroma and dermatofibrosarcoma.

Dermatofibrosarcoma protuberans (DFSP) and histiocytofibroma (HF) are two rare fibrohistiocytic tumors, with some overlapping pathologic features. Immunohistochemistry is very useful in these cases. CD34 is a commonly used marker. However, the increasing cases of CD34 negative DFSP make it pressing to test other immunohistochemical markers that could help in the differential diagnosis. DFSP is known to harbor COL1A1-PDGFB rearrangement. Tumors in the differential diagnosis of DFSP usually lack this molecular signature. Recent studies suggested the interaction of PDGFB and PDGF receptor b with various signaling pathways, including the Akt-mTOR pathway. Cyclin D1, one of the oncoproteins activated in this pathway, may represent a promising useful biomarker in the differential diagnosis. On the other hand, CD10 expression in specialized mesenchymal skin cells, and especially in fibrohistiocytic skin tumors has been reported, which raises the interest of using this biomarker in HF and DFSP. In this study, we aimed to compare the expression of CD10 and cyclin D1 in 15 cases of DFSP and 15 cases of HF and discuss their potential contribution in the differential diagnosis.

LncRNA ANRIL Silencing Alleviates High Glucose-Induced Inflammation, Oxidative Stress, and Apoptosis via Upregulation of MME in Podocytes.

Diabetic nephropathy (DN), characterized by glomerular injury, is a common complication of both type 1 and type 2 diabetes, accompanied by massive proteinuria. Podocytes are reported to play pivotal roles in maintaining the glomerular filtration barrier. In addition, the expression of long non-coding RNAs (lncRNAs) ANRIL was upregulated in type 2 diabetes patients. Hence, the aim of this study was to investigate the underlying mechanisms implicated the role of LncRNA ANRIL in podocyte injury in DN. The concentration of inflammatory cytokines was quantified by the corresponding enzyme-linked immunosorbent assay (ELISA) kits. The mRNA levels of the target gene were determined by reverse transcription and real-time quantitative PCR (RT-qPCR). The expressions of proteins were evaluated by Western blot. The activities of lactate dehydrogenase (LDH), superoxide dismutase (SOD), and malondialdehyde (MDA) level were measured by corresponding commercial kits. Finally, the apoptosis of podocytes was analyzed by TUNEL assay. In our study, LncRNA ANRIL was highly expressed in high glucose (HG)-induced podocytes. Moreover, LncRNA ANRIL silencing attenuated HG-induced inflammation, oxidative stress, and apoptosis and induced MME overexpression in podocytes. Interestingly, MME knockdown abolished the suppressive effect of LncRNA ANRIL silencing on HG-induced inflammation, oxidative stress, and apoptosis in podocytes. LncRNA ANRIL silencing alleviates HG-induced inflammation, oxidative stress, and apoptosis via upregulation of MME in podocytes. Hence, LncRNA ANRIL may be a novel and effective target to ameliorate podocyte injury in DN.

Maternal Overweight Downregulates MME (Neprilysin) in Feto-Placental Endothelial Cells and in Cord Blood.

Maternal overweight in pregnancy alters the metabolic environment and generates chronic low-grade inflammation. This affects fetal development and programs the offspring's health for developing cardiovascular and metabolic disease later in life. MME (membrane-metalloendopeptidase, neprilysin) cleaves various peptides regulating vascular tone. Endothelial cells express membrane-bound and soluble MME. In adults, the metabolic environment of overweight and obesity upregulates endothelial and circulating MME. We here hypothesized that maternal overweight increases MME in the feto-placental endothelium. We used primary feto-placental endothelial cells (fpEC) isolated from placentas after normal vs. overweight pregnancies and determined MME mRNA, protein, and release. Additionally, soluble cord blood MME was analyzed. The effect of oxygen and tumor necrosis factor α (TNFα) on MME protein in fpEC was investigated in vitro. Maternal overweight reduced MME mRNA (-39.9%, p < 0.05), protein (-42.5%, p = 0.02), and MME release from fpEC (-64.7%, p = 0.02). Both cellular and released MME protein negatively correlated with maternal pre-pregnancy BMI. Similarly, cord blood MME was negatively associated with pre-pregnancy BMI (r = -0.42, p = 0.02). However, hypoxia and TNFα, potential negative regulators of MME expression, did not affect MME protein. Reduction of MME protein in fpEC and in cord blood may alter the balance of vasoactive peptides. Our study highlights the fetal susceptibility to maternal metabolism and inflammatory state.

Spinal Versus Intracranial Meningioma: Aberrant Expression of CD10 and Inhibin with Relation to Clinicopathological Features and Prognosis.

CD10 and inhibin are used mainly in CNS pathology to distinguish hemangioblastoma from metastatic clear cell renal cell carcinoma. Some meningiomas can mimic both tumors and so we aimed at this study to investigate the expression of both markers in a large number of meningioma cases. One hundred thirty-four meningioma samples were collected, 14 of them were spinal and 120 were intracranial. Manual TMA blocks were constructed using modified mechanical pencil tip method and immunohistochemistry for CD10 and inhibin was done. Intracranial meningioma occurred in significantly younger age than spinal ones. Most of spinal meningiomas were of transitional histology. CD10 was expressed in 14% of cases with significant positivity in spinal rather than intracranial cases. Transitional meningiomas showed the highest positivity for CD10 expression, while the least positive was the meningiotheliomatous type. Inhibin was expressed in 6% of cases with no significant relation to clinicopathological and histological features. There was no significant relationship between the expression of CD10 and inhibin expression in meningiomas. In conclusion, spinal meningiomas differ than intracranial ones in many clinicopathological and biological aspects. Among these differences is CD10 expression being more expressed in spinal meningiomas. However CD10 and inhibin are aberrantly expressed in a proportion of meningiomas, both have no relations to poor prognostic factors but more caution should be exerted during usage of these markers in diagnosis of hemangioblastoma and metastatic RCC. Further studies are suggested for exploring more biological differences between spinal and intracranial meningiomas.

Placental Syncytiotrophoblast-Derived Extracellular Vesicles Carry Active NEP (Neprilysin) and Are Increased in Preeclampsia.

NEP (neprilysin) is a widely expressed membrane-bound metalloprotease, which binds and cleaves a variety of peptides including vasodilators, natriuretics, and diuretics. Higher levels of NEP result in hypertension-a cardinal feature of the placental disease preeclampsia. Syncytiotrophoblast-derived extracellular vesicles (EVs), comprising microvesicles and exosomes, are released into the peripheral circulation in pregnancy and are postulated as a key mechanism coupling placental dysfunction and maternal phenotype in preeclampsia. We aimed to determine whether higher levels of active NEP are found in syncytiotrophoblast-derived EVs in preeclampsia compared with normal pregnancy. Using immunostaining and Western blotting, we first demonstrated that NEP levels are greater not only in preeclampsia placental tissue but also in syncytiotrophoblast-derived microvesicles and exosomes isolated from preeclampsia placentas ( P<0.05, n=5). We confirmed placental origin using antibody-coated magnetic beads to isolate NEP-bound vesicles, finding that they stain for placental alkaline phosphatase. NEP on syncytiotrophoblast-derived EVs is active and inhibited by thiorphan ( P<0.01, n=3; specific inhibitor). Syncytiotrophoblast-derived microvesicles, isolated from peripheral plasma, demonstrated higher NEP expression in preeclampsia using flow cytometry ( P<0.05, n=8). We isolated plasma exosomes using size-exclusion chromatography and showed greater NEP activity in preeclampsia ( P<0.05, n=8). These findings show that the placenta releases active NEP into the maternal circulation on syncytiotrophoblast-derived EVs, at significantly greater levels in preeclampsia. NEP has pathological roles in hypertension, heart failure, and amyloid deposition, all of which are features of preeclampsia. Circulating syncytiotrophoblast-derived EV-bound NEP thus may contribute to the pathogenesis of this disease.

CD10, TDAG51, CK20, AR, INSM1, and Nestin Expression in the Differential Diagnosis of Trichoblastoma and Basal Cell Carcinoma.

BACKGROUND: Trichoblastoma (TB) and basal cell carcinoma (BCC) are 2 different neoplasms composed of basaloid cells and have overlapping histopathological features. We compared the immunoexpression of CD10, T-cell death-associated gene 51 (TDAG51), cytokeratin 20 (CK20), androgen receptor (AR), insulinoma-associated protein 1 (INSM1), and nestin for the differential diagnosis of these tumors. MATERIALS AND METHODS: We assessed a total of 27 BCC and 27 TB cases, including 4 TB lesions in nevus sebaceous and 3 malignant TB lesions for CD10, TDAG51, CK20, AR, INSM1, and nestin expression. RESULTS: Staining for CK20, TDAG51, INSM1, and stromal CD10 was significantly more common in TB cases than in BCC cases ( P < .001). Epithelial CD10 and AR staining was significantly more common in BCC cases than in TB cases ( P < .001). The difference between the groups for nestin staining was not significant ( P > .05). Stromal CD10 staining was the most sensitive marker (96.3%) and INSM1 the least sensitive (55.6%) marker for TB. TDAG51 showed 100% specificity for TB. A larger number of CK20 positive cells was found in the cases associated with nevus sebaceous than in the other TBs. CONCLUSION: All the selected markers except nestin were useful for the differential diagnosis between TB and BCC. CD10 and TDAG51 were more useful than the other markers. The use of CK20 could be preferred in nevus sebaceous lesions. INSM1 was less effective in highlighting Merkel cells within the lesion than CK20.

Primary cutaneous vs secondary cutaneous follicular lymphomas: A comparative study focused on BCL2, CD10, and t(14;18) expression.

BACKGROUND: Primary cutaneous follicular center-cell lymphoma (PCFCL) is one of the most common types of cutaneous B-cell lymphoma. Differences in immunohistochemical expression of BCL2 and CD10 antigens along with the presence of t(14:18) translocation in neoplastic cells have been postulated as relevant clues in differentiating PCFCL from cutaneous lesions secondary to a systemic follicular lymphoma (SCFL). The aim of this study is to evaluate the significance and usefulness of these parameters in a large series of patients. METHODS: Patients with PCFCL and SCFL diagnosed at three university hospitals in Barcelona, from 2000 to 2015 were reviewed. Clinical, histopathological, immunophenotypical, genetic, and outcome parameters were analyzed. RESULTS: Eighty-one cases (59 PCFCL and 22 SCFL) were included. There were no significant differences between PCFCL and SCFL cases regarding clinical presentation, site of involvement, or predominant type of skin lesions. Most patients in both groups showed positivity for BCL2 and CD10, but strong expression of BCL2 and CD10 was associated with SCFL cases. Although more frequent in SCFL, a small proportion of PCFCL cases also showed the t(14:18) on FISH analysis. CONCLUSION: The intensity of BCL2 expression was found to be the single most valuable clue in differentiating PCFCL from SCFL cases on histopathological grounds.

Chronic benzodiazepine suppresses translocator protein and elevates amyloid ß in mice.

Benzodiazepine (BZD) is a commonly prescribed anxiolytic and sedation aid medication, especially in elderly women. However, long-term use of BZD provokes adverse nontherapeutic effects that include movement deficit. Here, we investigated motoric deficit and molecular changes in cerebellum associated with the chronic use of BZD (cBZD) in female mice. We measured neuroprotective translocator protein (TSPO), neurotoxic amyloid ß (Aß), Aß-producing presenilin-1 (PS1), and Aß-degrading neprilysin. We also tested whether cBZD treatment damages mitochondrial membranes by measuring mitochondrial membrane swelling and mitochondrial respiration. Young and old mice received BZD (lorazepam) for 20 days, were tested for motoric function using Rotarod, and then euthanized to collect cerebellum. The major methods were immunoblot and RT-PCR for TSPO, PS1, and neprilysin expressions; ELISA for Aß level; spectrometry for mitochondrial membrane swelling; XF-respirometry for mitochondrial respiration. cBZD-treated old mice showed poorer motoric function than old control or young cBZD-treated mice. Old mice treated with cBZD showed a decrease in TSPO and neprilysin and an increase in Aß and PS1 production compared to old control mice. Old cBZD-mice also showed an increase in mitochondrial membrane swelling and a decrease in mitochondrial respiration. These data suggest that cBZD exacerbates motoric aging in a manner that involves diminished TSPO, elevated Aß, and mitochondrial damage.

High expression of CD10 in anaplastic thyroid carcinomas.

AIMS: CD10 is an endopeptidase that degrades various bioactive peptides in the extracellular matrix. In addition to enzymatic degradation, it affects multiple intracellular signal transduction pathways. CD10 expression has been extensively studied in human epithelial cancers of numerous organs and sites. However, its presence in thyroid carcinomas, especially in anaplastic thyroid carcinoma (ATC), has not been fully determined. An actual CD10 expression in thyroid lesions including a large series of ATC was evaluated. METHODS AND RESULTS: We examined CD10 by immunohistochemistry (IHC) in 152 thyroid lesions: nine adenomatous goitres (AGs) and 143 tumours, including 47 anaplastic carcinomas. IHC showed diffuse and strong positivity for CD10 in the epithelial components of almost all ATCs. However, epithelia with squamous metaplasia and oncocytic change from AGs, follicular adenomas and differentiated carcinomas had focal CD10 reactivity. Some papillary thyroid carcinomas (PTCs), along with the PTC components of some ATCs, showed CD10 positivity in fibroblast-like stromal cells and fibrous material. CONCLUSION: Our results imply that the CD10 expression pattern depended on the histotypes of thyroid lesions. When possible metastatic tumours and non-epithelial tumours are excluded, high CD10 expression may be useful in determining whether a primary thyroid carcinoma includes an anaplastic component.

CD10 expression pattern in prostatic adenocarcinoma: Elucidation of differences between Gleason's grades.

CD10, a transmembrane endopeptidase, has been shown to be lost as an early event in prostate cancer. We aimed at evaluating the pattern of expression of CD10 in various Gleason's grades of prostatic adenocarcinoma in comparison with nodular hyperplasia of prostate. This retrospective study included 30 cases of nodular hyperplasia and 30 of prostatic adenocarcinoma of various Gleason's grades. Immunohistochemical staining for CD10 was performed on all cases and positivity evaluated as percentage of cells as well as location (membranous or cytoplasmic or both). Of prostatic adenocarcinomas, grade 3 was seen in 10 foci, grade 4 in 28 and grade 5 in 22 foci. CD10 positivity in carcinoma was lower than in nodular hyperplasia, with the lowest positivity in grade 5. The pattern of expression of CD10 also changed from membranous in grade 3 to cytoplasmic in grade 5. Loss of CD10 expression appears to be associated with increasing tumour grade in carcinoma prostate and this can potentially be useful in stratification of such patients.

Co-Administration of TiO2 Nanowired Mesenchymal Stem Cells with Cerebrolysin Potentiates Neprilysin Level and Reduces Brain Pathology in Alzheimer's Disease.

Neprilysin (NPL), the rate-limiting enzyme for amyloid beta peptide (AßP), appears to play a crucial role in the pathogenesis of Alzheimer's disease (AD). Since mesenchymal stem cells (MSCs) and/or cerebrolysin (CBL, a combination of neurotrophic factors and active peptide fragments) have neuroprotective effects in various CNS disorders, we examined nanowired delivery of MSCs and CBL on NPL content and brain pathology in AD using a rat model. AD-like symptoms were produced by intraventricular (i.c.v.) administration of AßP (1-40) in the left lateral ventricle (250 ng/10 µl, once daily) for 4 weeks. After 30 days, the rats were examined for NPL and AßP concentrations in the brain and related pathology. Co-administration of TiO2-nanowired MSCs (106 cells) with 2.5 ml/kg CBL (i.v.) once daily for 1 week after 2 weeks of AßP infusion significantly increased the NPL in the hippocampus (400 pg/g) from the untreated control group (120 pg/g; control 420 ± 8 pg/g brain) along with a significant decrease in the AßP deposition (45 pg/g from untreated control 75 pg/g; saline control 40 ± 4 pg/g). Interestingly, these changes were much less evident when the MSCs or CBL treatment was given alone. Neuronal damages, gliosis, and myelin vesiculation were also markedly reduced by the combined treatment of TiO2, MSCs, and CBL in AD. These observations are the first to show that co-administration of TiO2-nanowired CBL and MSCs has superior neuroprotective effects in AD probably due to increasing the brain NPL level effectively, not reported earlier.

Aberrant expression of CD10 and BCL6 in mantle cell lymphoma.

AIMS: Mantle cell lymphoma (MCL) is characterized by distinctive histological and molecular features. Aberrant expression of BCL6 and CD10 has been reported occasionally, but the biological features of such cases are largely unknown. This study aimed to define the epidemiological, histological and cytogenetic characteristics of BCL6 and CD10-positive MCLs, also investigating possible biological features. METHODS AND RESULTS: A total of 165 cases of cyclin D1 and t(11;14)(q13;q34)-positive MCLs were studied for CD10 and BCL6 immunohistochemical expression, which was documented in 26 of 165 (15.8%) cases (BCL6 17 of 165; CD10 11 of 165; BCL6 and CD10 co-expression two of 165). CD10-positivity was significantly more frequent in females (63.3%; P < 0.01). Either expression correlated significantly with higher mean proliferation index and higher prevalence of MUM1 positivity (P < 0.05). Fluorescence in-situ hybridization (FISH) for BCL6 (3q27) gene derangements was performed on the BCL6- and CD10-positive cases and 98 matched controls: amplifications were documented more frequently in BCL6-positive than -negative cases (50.0% versus 19.4% of cases) (P < 0.05). The mutational status of the variable immunoglobulin heavy chain genes (IGVH) was investigated by Sanger sequencing: five of the six successfully tested cases (83.3%) showed no somatic hypermutations. CONCLUSIONS: Aberrant CD10 and BCL6 expression defines a subset of MCLs with higher mean Ki-67 index and higher prevalence of MUM1 expression. BCL6 protein positivity correlates with cytogenetic aberrations involving the BCL6 gene. Although examined successfully in few cases, the high prevalence of unmutated IGVH genes also points at a pregerminal cell origin for these phenotypically aberrant cases.

Sequential activation of different pathway networks in ischemia-affected and non-affected myocardium, inducing intrinsic remote conditioning to prevent left ventricular remodeling.

We have analyzed the pathway networks of ischemia-affected and remote myocardial areas after repetitive ischemia/reperfusion (r-I/R) injury without ensuing myocardial infarction (MI) to elaborate a spatial- and chronologic model of cardioprotective gene networks to prevent left ventricular (LV) adverse remodeling. Domestic pigs underwent three cycles of 10/10 min r-I/R by percutaneous intracoronary balloon inflation/deflation in the mid left anterior descending artery, without consecutive MI. Sham interventions (n = 8) served as controls. Hearts were explanted at 5 h (n = 6) and 24 h (n = 6), and transcriptomic profiling of the distal (ischemia-affected) and proximal (non-affected) anterior myocardial regions were analyzed by next generation sequencing (NGS) and post-processing with signaling pathway impact and pathway network analyses. In ischemic region, r-I/R induced early activation of Ca-, adipocytokine and insulin signaling pathways with key regulator STAT3, which was also upregulated in the remote areas together with clusterin (CLU) and TNF-alpha. During the late phase of cardioprotection, antigen immunomodulatory pathways were activated with upregulation of STAT1 and CASP3 and downregulation of neprilysin in both zones, suggesting r-I/R induced intrinsic remote conditioning. The temporo-spatially differently activated pathways revealed a global myocardial response, and neprilysin and the STAT family as key regulators of intrinsic remote conditioning for prevention of adverse remodeling.

Expression of neprilysin in periodontitis-affected gingival tissues.

OBJECTIVE: Although the pathogeneses of Alzheimer's disease (AD) and periodontal diseases have overlapping features, including ageing and chronic inflammation, the association between AD and periodontitis remains unclear. To explore the pathogenesis of periodontitis, a comprehensive gene expression/transcriptome analysis in periodontitis-affected gingival tissues found that the AD pathway was significantly up-regulated in periodontitis-affected gingival tissues. AD-related genes, amyloid beta precursor protein (APP), interleukin-1 beta and compliment 1QA, were significantly elevated in periodontitis. In the present study, balance between mRNA expression of APP and a potent amyloid degradation enzyme, neprilysin (NEP), as well as protein localisation of APP and NEP were analysed. DESIGN: Eighteen periodontitis-affected and 18 clinically healthy control gingival tissues were taken from patients with severe chronic periodontitis or undergoing tooth extraction. Total RNA was purified and used for quantitative reverse transcription real-time polymerase chain reaction (qRT-PCR). The localisation of APP and NEP was analysed by immunohistochemistry (IHC). RESULTS: Both APP and NEP genes were up-regulated in periodontitis-affected gingival tissues. APP-expressing macrophages and NEP-expressing neutrophils and fibroblasts, reflecting inflammatory stages, were detected in inflamed gingival tissues by IHC. CONCLUSION: The up-regulation of APP and NEP mRNA levels in periodontitis-affected gingival tissues compared with healthy controls was confirmed by qRT-PCR analyses. Since NEP is one of the primary enzymes that degrades amyloid beta, increased NEP mRNA levels in periodontitis may act as an inhibitor of amyloid beta accumulation in gingival tissues, balancing increased APP mRNA expression. However, NEP has several effects including degradation of vasoactive substances; therefore, further sresearch is needed.

Mature CD10+ and immature CD10- neutrophils present in G-CSF-treated donors display opposite effects on T cells.

The identification of discrete neutrophil populations, as well as the characterization of their immunoregulatory properties, is an emerging topic under extensive investigation. In such regard, the presence of circulating CD66b+ neutrophil populations, exerting either immunosuppressive or proinflammatory functions, has been described in several acute and chronic inflammatory conditions. However, due to the lack of specific markers, the precise phenotype and maturation status of these neutrophil populations remain unclear. Herein, we report that CD10, also known as common acute lymphoblastic leukemia antigen, neutral endopeptidase, or enkephalinase, can be used as a marker that, within heterogeneous populations of circulating CD66b+ neutrophils present in inflammatory conditions, clearly distinguishes the mature from the immature ones. Accordingly, we observed that the previously described immunosuppressive neutrophil population that appears in the circulation of granulocyte colony-stimulating factor (G-CSF)-treated donors (GDs) consists of mature CD66b+CD10+ neutrophils displaying an activated phenotype. These neutrophils inhibit proliferation and interferon γ (IFNγ) production by T cells via a CD18-mediated contact-dependent arginase 1 release. By contrast, we found that immature CD66b+CD10- neutrophils, also present in GDs, display an immature morphology, promote T-cell survival, and enhance proliferation and IFNγ production by T cells. Altogether, our findings uncover that in GDs, circulating mature and immature neutrophils, distinguished by their differential CD10 expression, exert opposite immunoregulatory properties. Therefore, CD10 might be used as a phenotypic marker discriminating mature neutrophils from immature neutrophil populations present in patients with acute or chronic inflammatory conditions, as well as facilitating their isolation, to better define their specific immunoregulatory properties.

Menin and Daxx Interact to Suppress Neuroendocrine Tumors through Epigenetic Control of the Membrane Metallo-Endopeptidase.

Neuroendocrine tumors (NET) often harbor loss-of-function mutations in the MEN1 and DAXX tumor suppressor genes. Here, we report that the products of these genes, menin and Daxx, interact directly with each other to suppress the proliferation of NET cells, to a large degree by inhibiting expression of the membrane metallo-endopeptidase (MME). Menin and Daxx were required to enhance histone H3 lysine9 trimethylation (H3K9me3) at the MME promoter, as mediated partly by the histone H3 methyltransferase SUV39H1. Notably, the menin T429K mutation associated with a NET syndrome reduced Daxx binding, MME repression, and proliferation of NET cells. Conversely, inhibition of MME in NET cells repressed proliferation and tumor growth in vivo Our findings reveal a previously unappreciated cross-talk between two crucial tumor suppressor genes thought to work by independent pathways, focusing on MME as a common target of menin/Daxx to treat NET. Cancer Res; 77(2); 401-11. ©2016 AACR.

Reduction and fragmentation of elastic fibers in the skin of obese mice is associated with altered mRNA expression levels of fibrillin-1 and neprilysin.

AIM OF THE STUDY: Our previous research suggested that obesity induces structural fragility in the skin. Elastic fibers impart strength and elasticity. In this study, we determined whether elastic fibers decrease in the skin of obese mice. MATERIALS AND METHODS: To confirm alterations in elastic fiber content due to obesity, we used spontaneously obese model mice (TSOD) and control mice (TSNO). Furthermore, to evaluate the elastin structure and gene expression dependent on the severity of obesity, an obesity-enhanced mouse model was developed by feeding a high fat diet to TSOD (TSOD-HF). Back skin samples were stained with hematoxylin and eosin and Elastica van Gieson for microscopic examination, and the samples were stained for immunohistochemical analysis of neprilysin. Gene expression levels were determined using a real-time PCR system. RESULTS: The abundance of elastic fibers beneath the epidermis was remarkably reduced and fragmented in TSOD as compared with TSNO. Fibrillin-1 mRNA levels in TSOD were significantly suppressed compared with those in TSNO, whereas neprilysin mRNA levels and immunohistochemical expression in TSOD were significantly increased, as compared with those in TSNO. The reduction of elastic fibers was enhanced and the expression levels of elastic fiber formed factors were significantly suppressed in TSOD-HF, as compared with those in the TSOD. CONCLUSIONS: The abundance of elastic fibers was reduced and fragmented in obesity, suggesting that the reduction in elastic fibers is initially caused by increased neprilysin and decreased fibrillin-1 expression, which may inhibit formation and stabilization of elastic fibers, resulting in skin fragility in obesity.

Green tea reduces body fat via upregulation of neprilysin.

BACKGROUND/OBJECTIVE: Consumption of green tea has become increasingly popular, particularly because of claimed reduction in body weight. We recently reported that animals with pharmacological inhibition (by candoxatril) or genetic absence of the endopeptidase neprilysin (NEP) develop an obese phenotype. We now investigated the effect of green tea extract (in drinking water) on body weight and body composition and the mediating role of NEP. SUBJECTS/METHODS: To elucidate the role of NEP in mediating the beneficial effects of green tea extract, 'Berlin fat mice' or NEP-deficient mice and their age- and gender-matched wild-type controls received the extract in two different doses (300 or 600 mg kg-1 body weight per day) in the drinking water. RESULTS: In 'Berlin fat mice', 51 days of green tea treatment did not only prevent fat accumulation (control: day 0: 30.5% fat, day 51: 33.1%; NS) but also reduced significant body fat (green tea: day 0: 27.8%, day 51: 20.9%, P<0.01) and body weight below the initial levels. Green tea reduced food intake. This was paralleled by a selective increase in peripheral (in kidney 17%, in intestine 92%), but not central NEP expression and activity, leading to downregulation of orexigens (like galanin and neuropeptide Y (NPY)) known to be physiological substrates of NEP. Consequently, in NEP-knockout mice, green tea extract failed to reduce body fat/weight. CONCLUSIONS: Our data generate experimental proof for the assumed effects of green tea on body weight and the key role for NEP in such process, and thus open a new avenue for the treatment of obesity.