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Background: Anti-neutrophil cytoplasmic antibody vasculitis is characterized by antibodies to myeloperoxidase or proteinase 3. Previous work in murine anti-myeloperoxidase vasculitis has shown a role for the alternative pathway complement component factor B and the anaphylatoxin C5a. However, mice deficient in properdin, which stabilizes the alternative pathway convertase, were not protected. V-Type immunoglobulin domain-containing suppressor of T-cell activation (VISTA)-deficient mice were protected in the nephrotoxic nephritis model but the role of VISTA in anti-myeloperoxidase vasculitis is unknown. Objectives: This study had 2 aims. First, we attempted to reproduce previous findings on the role of factor B in anti-myeloperoxidase vasculitis. Second, we examined the role of VISTA in this model, in order to see if the protection in the nephrotoxic nephritis model extended to anti-myeloperoxidase vasculitis. Methods: Anti-myeloperoxidase vasculitis was induced in wild type, factor B, or VISTA deficient mice. Disease was assessed by quantifying glomerular crescents and macrophages, in addition to albuminuria and serum creatinine. Results: When wild type and factor B deficient mice were compared, there were no differences in any of the histological or biochemical parameters of disease assessed. Similarly, when wild type or VISTA deficient mice were compared, there were no differences. Conclusions: Factor B deficient mice were not protected which is in contrast to previous studies. Therefore alternative pathway activation is not essential in this model, under the conditions used in this study. VISTA deficient mice were not protected, suggesting that therapies targeting VISTA may not be effective in vasculitis.

EGFR plays key roles in multiple cellular processes such as cell differentiation, cell proliferation, migration and epithelia homeostasis. Phosphorylation of the receptor, intracellular signaling and trafficking are major events regulating EGFR functions. Galectin-7, a soluble lectin expressed in epithelia such as the skin, has been shown to be involved in cell differentiation. Through this study we demonstrate that galectin-7 regulates EGFR function by a direct interaction with its extracellular domain hence modifying its downstream signaling and endocytic pathway. From observations in mice we focused on the molecular mechanisms deciphering the glycosylation dependent interaction between EGFR and galectin-7. Interestingly, we also revealed that galectin-7 is a direct binder of both EGFR and E-cadherin bridging them together. Strikingly this study not only deciphers a new molecular mechanism of EGFR regulation but also points out a novel molecular interaction between EGFR and E-cadherin, two major regulators of the balance between proliferation and differentiation.SUMMARYEGFR and E-cadherin are known to interact and to regulate epithelial homeostasis. In this study we unravel in the epidermis a new partner and regulator of EGFR which also binds E-cadherin reciprocally bridging their dynamics and functions.

Sterols and sterol oxidation products (SOPs) are well-known dietary factors influencing atherosclerosis; however, their distribution in vivo after dietary sterol/SOP intake is still unclear. Here, we investigated the tissue distribution of sterols and SOPs in ApoE-/- mice after dietary exposure to diets supplemented with phytosterols (PS), phytosterol oxidation products (POPs), or cholesterol oxidation products (COPs). The results showed that PS intake reduced cholesterol in serum and the liver but increased cholesterol in the brain. PS intake increased the levels of PS in vivo and the levels of 7-keto- and triol-POPs in serum and the liver. COP intake elevated the level of all COPs in serum but did not change the 7-keto-cholesterol level in the liver and brain. All POPs in serum and parts of POPs in the liver and brain increased after dietary POP exposure. Our study indicated that dietary PS and SOPs accumulated in vivo with varying degrees and influenced cerebral cholesterol metabolism.

Marine-derived bioactive peptides are widely studied and used as functional foods. The aim of this study was to investigate the effects of low molecular-weight (Mw) peptides (150 Da

Choline is an important nutrient during pregnancy and lactation. Maternal choline deficiency in CD-1 mice lowers liver betaine levels in male offspring. By contrast, it increases elovl3 and vanin-1 mRNA levels in female offspring. Taken together, these observations suggest gender-specific responses to a choline-deficient diet.

In our previous study, fatty acid-binding protein 5 (FABP5) was expressed in septoclasts with long processes which are considered to resorb uncalcified matrix of the growth plate (GP) cartilage, and no apparent abnormalities were detected in the histo-architecture of the GP of FABP5-deficient (FABP5−/−) mice. Those finding lead us to hypothesize that another FABP can compensate the deletion of FABP5 in septoclasts of its gene-mutant mice. Based on the hypothesis, the present study examined the expression levels of several other FABPs in septoclasts and their morphology in FABP5−/− mouse tibiae. Processes of FABP5−/− septoclasts tend to be shorter than wild septoclasts. FABP4-positive septoclasts in FABP5−/− mice were more numerous than those cells in wild mice.Peroxisome proliferator-activated receptor (PPAR) γ was expressed in FABP4-positive septoclasts of FABP5−/− mice as well as mice administered with GW1929, a PPARγ agonist, suggesting that the occurrence of PPARγ induces an increase of FABP4-positive septoclasts. The present finding suggests that the functional exertion of FABP5 in septoclasts is supplemented by FABP4 in normal and FABP5−/− mice, and that the expression of FABP4 is up-regulated in accompany with PPARγ in FABP5−/− for maintenance of resorptive activity in the GP.

Objective: This study aimed to elucidate the role of the proangiogenic transcription factors Sox7 and Sox17 in the wound healing process and investigate the therapeutic potential of Dll4 blockade, which is an upstream regulator of Sox17, for the treatment of nonhealing wounds. Approach: After generating a full-thickness skin defect wound model of endothelial Sox7- and/or Sox17-deficient mice, we measured the wound healing rates and performed histological analysis. The effects of an anti-Dll4 antibody on wound angiogenesis in Sox7-deficient mice and db/db diabetic mice were assessed. Results: Sox7 and/or Sox17 deletion delayed wound healing. Moreover, the loss of Sox7 and Sox17 inhibited wound angiogenesis, without affecting the expression of the other. Of interest, after anti-Dll4 antibody treatment, Sox17 levels were increased and the suppression of angiogenesis was alleviated in Sox7-deficient mice and db/db diabetic mice. Consequently, Dll4 blockade effectively recovered the observed delay in wound healing. Innovation: The proangiogenic role of Sox7 and Sox17 in wound angiogenesis was addressed and effective treatment of nonhealing wounds by Dll4 blockade was suggested. Conclusion: This study revealed the proangiogenic role of the transcription factors Sox7 and Sox17 in wound angiogenesis. Furthermore, we suggest a novel method for treating nonhealing wounds by particularly targeting the Dll4-Sox17 axis.

Background Favism is an acute hemolytic syndrome caused by fava bean (FB) ingestion. The purpose of this study was to investigate the possible influences of FB on the metabonomic profile of erythrocytes in glucose-6-phosphate dehydrogenase (G6PD)-deficient (G6PDx) and wild-type (WT) mice. Results Ninety-two metabolites were identified in the comparison of the G6PDx and WT groups. Eighty-seven metabolites were identified in the erythrocytes of WT and G6PDx mice after FB ingestion. Thirty-eight metabolites were identified in the comparison of the FB-treated G6PDx and the FB-treated WT mouse groups. Among them, the number of glycerophospholipids (GPLs) and polyunsaturated fatty acids (PUFAs) changed significantly, which suggests that GPLs and PUFAs may be responsible for FB stress. Conclusion This study demonstrates that G6PD deficiency might affect the metabonomic profile of erythrocytes in response to FB. © 2020 Society of Chemical Industry.

The prevalence of non-alcoholic fatty liver disease (NAFLD) is constantly increasing, and altered expression of microRNAs (miRNAs) fosters the development and progression of many pathologies, including NAFLD. Therefore, we explored the role of new miRNAs involved in the molecular mechanisms that trigger NAFLD progression and evaluated them as biomarkers for diagnosis. As a NAFLD model, we used apolipoprotein E-deficient mice administered a high-fat diet for 8 or 18 weeks. We demonstrated that insulin resistance and decreased lipogenesis and autophagy observed after 18 weeks on the diet are related to a concerted regulation carried out by miR-26b-5p, miR-34a-5p, miR-149-5p and miR-375-3p. We also propose circulating let-7d-5p and miR-146b-5p as potential biomarkers of early stages of NAFLD. Finally, we confirmed that circulating miR-34a-5p and miR-375-3p are elevated in the late stages of NAFLD and that miR-27b-3p and miR-122-5p are increased with disease progression. Our results reveal a synergistic regulation of key processes in NAFLD development and progression by miRNAs. Further investigation is needed to unravel the roles of these miRNAs for developing new strategies for NAFLD treatment. This article has an associated First Person interview with the joint first authors of the paper., Summary: Apoe−/− mice administered a high-fat diet represent a model of non-alcoholic fatty liver disease, revealing the synergistic regulation of key processes in disease progression by miRNAs and indicating some miRNAs as biomarkers for diagnosis.

Background: Lysosomes are a central hub for cellular metabolism and are involved in the regulation of cell homeostasis through the degradation or recycling of unwanted or dysfunctional organelles through the autophagy pathway. Catalase, a peroxisomal enzyme, plays an important role in cellular antioxidant defense by decomposing hydrogen peroxide into water and oxygen. In accordance with pleiotropic significance, both impaired lysosomes and catalase have been linked to many age-related pathologies with a decline in lifespan. Aging is characterized by progressive accumulation of macromolecular damage and the production of high levels of reactive oxygen species (ROS). Although lysosomes degrade the most long-lived proteins and organelles via the autophagic pathway, the role of lysosomes and their effect on peroxisomes during aging is not known. The present study investigated the role of catalase and lysosomal function in catalase-knockout (KO) mice.Results: We found that catalase-deficient mice exhibited an aging phenotype faster than wild-type (WT) mice. We also found that aged catalase-KO mice induced leaky lysosomes by progressive accumulation of lysosomal contents, such as cathespin D, into the cytosol. Leaky lysosomes inhibited autophagosome formation and triggered impaired autophagy. The dysregulation of autophagy triggered mTORC1 (mechanistic target of rapamycin complex 1) activation, which plays a pivotal role in modulating aging. However, the antioxidant N-acetyl-L-cysteine (NAC) and mTORC1 inhibitor rapamycin rescued leaky lysosomes and aging phenotypes in catalase-deficient aged mice.Conclusion: This study unveils the new role of catalase and its role in lysosomal function during aging.

Introduction NADPH oxidase (NOX) 4-generated H2O2 has anti-atherosclerotic properties in conduit arteries like the aorta and carotids. However, the role of NOX4 on vascular function of small resistance arteries and blood pressure in a mouse model of familial hypercholesterolemia is unknown. Purpose We evaluated whether NOX4-generated H2O2 might play a role in perivascular adipose tissue of the thoracic aorta (tPVAT) and small resistance arteries on vascular function in a mouse model of familial hypercholesterolemia. Methods Aortic segments and mesenteric arteries from 26-week-old Ldlr−/− and Nox4−/− / Ldlr−/− mice were analysed by Mulvany myograph. In addition, vascular contraction and relaxation was analysed in the presence of L-NAME and catalase. Analysis of mRNA expression was performed in murine and human tissue by quantitative real-time PCR. Blood pressure was detected by tail cuff method in conscious, trained mice. Results Loss of NOX4 led to severe endothelial dysfunction in mesenteric arteries of Ldlr−/− mice. Blocking of NO synthases with L-NAME led to decreased endothelial relaxation in Ldlr−/− mice at the level of Nox4−/− / Ldlr−/− mice. However, incubation with L-NAME did not worsen the established endothelial dysfunction of the mesenteric arteries from Nox4−/− / Ldlr−/− mice. These results are strikingly different from the aorta, where inhibition of NO synthases led to a similarly impaired endothelial relaxation in both mouse strains. We detected a similar eNOS expression in the aorta of Ldlr−/− and Nox4−/− / Ldlr−/−, but a reduced eNOS expression in the mesenteric arteries of Nox4−/− / Ldlr−/− mice. H2O2 can induce eNOS expression. Therefore, we analysed the vascular function after catalase incubation and again found a significant reduction of endothelial function in the mesenteric arteries of Ldlr−/− mice. Finally, we analysed blood pressure of these mice and did not observe differences in systolic blood pressure, despite significant differences in endothelial function of resistant arteries. Conclusion NOX4 protects against severe endothelial dysfunction in the mesenteric artery in a model of hypercholesterolemia. Funding Acknowledgement Type of funding sources: Other. Main funding source(s): Ghanaian-German postgraduate training scholarship program (DAAD)

Background It was previously reported that red blood cells (RBCs) regulate blood flow via RBC-derived ATP [1]. Nevertheless, to the best of our knowledge, no study was performed to characterize possible alterations in RBC ATP levels in ApoE/LDLR−/− mice [2] which constitute a reliable model of human atherosclerosis, displaying distinct erythropathy [3]. Interestingly, young ApoE/LDLR−/− mice display higher exercise capacity and higher O2 carrying capacity of RBCs, as compared to their age-matched control [3,4]. However, it is not known whether increased exerise capacity in ApoE/LDLR−/− mice is linked to altered ATP release from RBCs. It was previously reported that prostacyclin analogs, known atheroprotective agents, which preserve vascular endothelium functions in various diseases [5,6], induce ATP release from human RBCs [1,7]. Purpose To characterize intra- and extra-cellular ATP levels in RBCs isolated from ApoE/LDLR−/− mice in comparison to control mice. Methods All experiments were conducted according to the Guidelines for Animal Care and Treatment of the EU and to the Local Ethical Committee on Animal Testing at our University. For experiments, 8- and 24-week-old C57BL/6 control mice (N=4–6 and N=5–8, respectively) and ApoE/LDLR−/− mice (N=4–7 and N=4–5, respectively) were used. The complete blood count, RBC morphology, biochemistry of blood plasma, RBC deformability, and RBC phosphatidylserine exposure were assessed. The intra- and extra-cellular ATP levels and ATP release from RBCs due to administration of iloprost (100 nM, 1 μM, 10 μm) were studied. Results Intracellular ATP level in RBCs isolated from 8-week-old ApoE/LDLR−/− mice was considerably lower as compared to their age-matched control (7.72±0.77 and 21.23±3.40 pmoles/1x106 RBCs, respectively). In 24-week-old mice, intracellular ATP in RBCs was low not only in ApoE/LDLR−/− mice but also in control mice (8.70±1.30 and 6.27±0.96 pmoles/1x106 RBCs, respectively). Basal extracellular ATP released from RBCs over 30 min incubation was 400 times lower than corresponding intracellular level, and mirrored intracellular ATP levels in all studied groups. Iloprost (100 nM–10 μM) did not produce robust ATP release in any of the studied groups, with only some effects when the highest concentration was used (10 μM). Conclusion(s) Hypercholesterolemia-dependent changes in young ApoE/LDLR−/− mice prior to atherosclerotic plaque development may induce a severe fall in intracellular ATP levels in the RBCs that might be linked to a possible diversion of glycolysis to 2,3-DPG to increase oxygen delivery, and might contribute to the alterations in RBC-dependent regulation of blood flow in ApoE/LDLR−/−. Further studies are required to mechanistically explain these findings. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): 1) National Science Centre, Poland (UMO 2016/23/B/ST4/00795) 2) the Innovation Incubator 4.0 project funded by the Ministry of Science and Higher Education, Poland (POIR 2014-2020)

Background Autophagy is linked to preventing the development of cardiac hypertrophy and failure. While aberrant activation of Ca2+/calmodulin-dependent kinase II (CaMKII) promotes myocardial remodeling, the role of autophagy in maintaining cardiac Ca2+ homeostasis and regulating CaMKII signaling is unknown. Objective To test whether loss of autophagy promotes subcellular alterations in CaMKII activation in early myocardial remodelling, and whether compromised in vivo cardiac function parallels those changes. Methods Young (10–15 weeks) cardiomyocyte-specific autophagy protein 5-deficient mice (Atg5−/−) mice and their littermate controls (Atg5+/+) underwent comprehensive in vivo phenotyping using echocardiography, exercise tolerance and hemodynamic stress testing. In vitro assessment included gravimetry, qPCR of hypertrophy marker genes and cellular and nuclear dimensions of isolated ventricular myocytes. CaMKII activation was studied by immunocytochemistry in cardiomyocytes upon exposure to basal (1Hz) or high (4Hz) pacing frequency. Autophosphorylated CaMKII (pT286) signal was evaluated in different subcellular spaces (i.e. cytoplasm, nucleoplasm and nuclear envelope). Results Before symptomatic cardiac dysfunction occurred, Atg5−/− mice showed compromised cardiac reserve in response to β-adrenergic stimulation (dp/dt max: 9475±126 vs 7364±496 mmHg/s, N=4–5; p=0.041), despite similar maximum heart rate. Consequently, effort intolerance (distance run: 251±22 vs 152±13 m, N=8; p=0.03) and maximal oxygen consumption (2093±66 vs 1763±131 ml/h/kg, N=8; p=0.04) were reduced during treadmill exercise tolerance testing. Increased heart-to-body weight ratio (8.1±0.5 vs 10.2±0.8 N=9; p=0.017) was associated with elevated mRNA expression of hypertrophy marker NppB (278% of Atg5+/+, N=5; p=0.016) in Atg5−/− mice, which showed enlarged cardiomyocytes and nuclei, as width-to-length ratio. Because Atg5−/− cardiomyocytes exhibit elevated nuclear Ca2+ levels at high pacing frequency, we now measured subcellular CaMKII activation under the same experimental conditions. Interestingly, at 1Hz, p-CaMKII was increased specifically at the nuclear envelope (154% of Atg5+/+, N=5 mice, 153–159 cells; p=0.029), but not in the cytoplasm or nucleoplasm. Increasing pacing frequency to 4Hz did not alter p-CaMKII levels in Atg5+/+ cells. However, p-CaMKII was increased by ∼30% and ∼20% in the cytoplasm and nucleoplasm of Atg5−/− cells respectively (N=5 mice, 153–155 cells). Conclusion Loss of ATG5-dependent autophagy causes cardiac hypertrophy and impaired cardiac reserve upon acute stress, which involves CaMKII activation, likely through the imbalance of nuclear Ca2+ load. Although, selective increase in p-CaMKII at the nuclear envelope in Atg5−/− mice may temporarily protect from nuclear Ca2+ overload, excessive CaMKII activation in the cytoplasm and the nucleoplasm upon increased workload, likely drives hypertrophic signalling toward heart failure in autophagy-defective mice. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Austrian Science Fund (FWF)

No abstract available.

Mechanical factors, especially wall shear stress (WSS) and circumferential strain (CS), play an important role in the progression and rupture of atherosclerotic plaques. Previous studies have shown that the temporal phase angle between WSS and CS, referred to as the stress phase angle (SPA) may be a biomarker for plaque development and vulnerability. Since the SPA is influenced by the severity and length of the stenosis, a multifactorial relationship between local hemodynamic variables and plaque morphology can be hypothesized. However, due to ethical restrictions and the difficulty of developing animal models, there is little experimental data to support such a hypothesis about the biomarker function of SPA. In this study, a novel non-invasive ultrasound-based method for investigating the relationship between local hemodynamics and plaque morphology is developed and investigated in-vitro and in-vivo with an apolipoprotein deficient mouse model. In the in-vitro experiments, using polyvinyl alcohol cryogel (PVA-c) phantoms, we have observed that the SPA becomes more negative and the wall shear rate (WSR) rises, as the severity of the stenosis increases. Conversely, SPA becomes more positive and WSR falls with increasing plaque length. These changes in plaque morphology have little effect on CS. The in-vivo experiments show that, as the severity of the plaque increases, the SPA becomes more negative and WSR tends to more positive values; whereas, the CS drops. We conclude that these local hemodynamic parameters such as SPA, WSR and CS, as suggested by others, can be regarded as prognostic markers for the assessment of plaque vulnerability.

IL-18 is ubiquitously produced by both hematopoietic and non-hematopoietic cells. The present study examined the thoracic aorta, including the surrounding perivascular adipose tissue (PVAT), of IL-18KO mice from functional and histological perspectives. IL-18KO mice exhibited raised blood pressure compared with wild-type mice. Echocardiographic examination showed a thickened vascular wall and narrowed vascular diameter of the aorta. Examination by the Magnus test demonstrated dysfunction of endothelial cells (ECs) in the IL-18KO thoracic aorta and impairment of the anticontractile function of IL-18KO PVAT. Histological examination showed no inflammatory lesions in the aorta but indicated progressive fibrosis in the vessel and conversion of PVAT from brown adipose tissue-like features to white adipose tissue-like features. Electron microscopic observation suggested several deformed mitochondria in the aorta and vacuole-like structures in ECs from IL-18KO mice. In addition, activity of complex IV was lower and production of reactive oxygen species was augmented in the mitochondria of IL-18KO aorta. Although expression of LC3 B was higher, rapamycin-induced autophagy flux was impaired in the IL-18KO PVAT. Moreover, Western blot analysis revealed that LAMP 1/2 was increased in IL-18KO PVAT, and measurement of cathepsin-D activity indicated decreased levels in IL-18KO PVAT. The IL-18KO thoracic aorta thus showed defects in physiological functions related to histological alterations, and the inflammasome/IL-18 system was suggested to play a protective role in cardiovascular cells, probably through quality control of mitochondria via promotion of autophagosome/autophagolysosome formation. NEW & NOTEWORTHY IL-18 deficiency caused aortic abnormalities in terms of morphology and functions in parallel with an accumulation of damaged mitochondria and anomalous turnover of protein complexes, such as PGC-1 and LAMP1 and -2 in PVAT. These findings suggested that IL-18 plays roles in maintaining the homeostasis of vessels and PVAT around the aorta, possibly by promoting autophagy.

Leptin receptor (LepR) signaling in neurons of the ventromedial nucleus of the hypothalamus (VMH), specifically those expressing steroidogenic factor-1 (SF1), have been proposed to play a key role in controlling energy balance. By crossing LepR-silenced (LepRloxTB) mice with those expressing SF1-Cre, we unsilenced native LepR specifically in the VMH and tested whether SF1 neurons in the VMH are critical mediators of leptin’s effect on energy homeostasis. LepRloxTB × SF1-Cre [knockout (KO)/Tg+] mice were metabolically phenotyped and compared with littermate controls that either expressed or were deficient in LepRs. Leptin-induced phosphorylated STAT3 was present in the VMH of KO/Tg+ mice and absent in other hypothalamic nuclei. VMH leptin signaling did not ameliorate obesity resulting from LepR deficiency in chow-fed mice. There was no change in food intake or energy expenditure when comparing complete LepR-null mice with KO/Tg+ mice, nor did KO/Tg+ mice show improved glucose tolerance. The presence of functional LepRs in the VMH mildly enhanced sensitivity to the pancreatic hormone amylin. When maintained on a high-fat diet (HFD), there was no reduction in diet-induced obesity in KO/Tg+ mice, but KO/Tg+ mice had improved glucose tolerance after 7 wk on an HFD compared with LepR-null mice. We conclude that LepR signaling in the VMH alone is not sufficient to correct metabolic dysfunction observed in LepR-null mice.

Atherosclerosis plays an important role in the pathology of coronary heart disease, cerebrovascular disease, and systemic vascular disease. Long non-coding RNAs (lncRNAs) are involved in most biological processes and are deregulated in many human diseases. However, the expression alteration and precise role of lncRNAs during atherosclerosis are unknown. We report here the systematic profiling of lncRNAs and mRNAs in an ApoE-deficient (ApoE−/−) mouse model of atherosclerosis. Clariom D solutions for the mouse Affymetrix Gene Chip were employed to analyze the RNAs from control and ApoE−/− mice. The functions of the differentially expressed mRNAs and lncRNAs and the relationships of their expression with atherosclerosis were analyzed by gene ontology, co-expression network, pathway enrichment, and lncRNA target pathway network analyses. Quantitative real-time PCR (QRT-PCR) was used to determine the expression of mRNAs and lncRNAs. A total of 2212 differentially expressed lncRNAs were identified in ApoE−/− mice, including 1186 up-regulated and 1026 down-regulated lncRNAs (|FC| ≥ 1.1, p −/− mice with 384 up-regulated and 806 down-regulated (|FC| ≥ 1.1, p

Purpose of Review: Bone turnover is a regulated process. Osteoglycin is suggested to have an important impact on bone function but may also affect cardiovascular and metabolic functions. This review investigates the action of osteoglycin in bone as well as its potential endocrine effects. Recent Findings: Osteoglycin is expressed by several tissues including bone and muscle. Some studies suggest that osteoglycin increases osteoblast differentiation whereas others suggest that osteoglycin decreases osteoblast differentiation. Thus, findings on the influence of osteoglycin in bone are conflicting. A recent study found increased bone mass in osteoglycin deficient mice. Another study reported that osteoglycin is a marker of low bone mineral density and vertebral fractures in women with type 2 diabetes. Furthermore, clinical studies link osteoglycin to insulin resistance and cardiovascular disease. Summary: Osteoglycin may be a novel marker of a muscle, pancreatic, and bone axis. However, current evidence is limited and further research investigating osteoglycin in both a pre-clinical and a clinical setting is needed.

Background and Objective As the interface between the oral cavity and the teeth, the junctional epithelial barrier is critical for gingival defense. The junctional epithelium is subject to mechanical stresses from biting force or external insults such as bacterial attacks, but little is known about the effects of mechanical stimuli on epithelial functions. Transient receptor potential vanilloid 4 (TRPV4) functions as a mechanosensitive nonselective cation channel. In the present study, based on marked expression of TRPV4 in the mouse junctional epithelium, we aimed to clarify the putative links between TRPV4 and junctional complexes in the junctional epithelium. Methods and Results Histological observations revealed that the junctional epithelium in TRPV4‐deficient (TRPV4−/−) mice had wider intercellular spaces than that in wild‐type (TRPV4+/+) mice. Exogenous tracer penetration in the junctional epithelium was greater in TRPV4−/− mice than in TRPV4+/+ mice, and immunoreactivity for adherens junction proteins was suppressed in TRPV4−/− mice compared with TRPV4+/+ mice. Analysis of a mouse periodontitis model showed greater bone volume loss in TRPV4−/− mice compared with TRPV4+/+ mice, indicating that an epithelial barrier deficiency in TRPV4−/− mice may be associated with periodontal complications. Conclusion The present findings identify a crucial role for TRPV4 in the formation of adherens junctions in the junctional epithelium, which could regulate its permeability. TRPV4 may be a candidate pharmacological target to combat periodontal diseases.

There continues to be considerable interest in the physiological role(s) of the hormone melatonin and its potential as a drug more than 60 years after its discovery. While there is an emphasis on human studies, there is still a need for animal models in biology. Laboratory strains of mice remain at the forefront of much biomedical research for many reasons. However, in the case of melatonin research, mice represent a problem that is often not recognized by researchers entering from other fields of biomedicine. In this review, I have brought together the results of a large number of studies in which melatonin was measured in the pineal gland and blood of different mouse strains. The unequivocal conclusion to be drawn from the review is that the majority of laboratory mouse strains do not produce melatonin, whereas the CBA and C3H strains produce substantial amounts of melatonin during the late dark period. Of course, this has been known from studies conducted more than 30 years ago, but papers continue to be published that report high levels of melatonin in the pineal glands and blood and melatonin metabolites in the urine of melatonin deficient strains. Reasons for these erroneous results are discussed and center around the use of unvalidated, poorly documented immunoassays and inadequate sample preparation (i.e. direct versus extracted assays). Finally, I discuss the validity of using extraordinary high doses (as high as 200 mg/kg) of melatonin administered to melatonin deficient mice in experiments. It is hoped that the presentation of multiple sources of data in one place documenting the actual melatonin deficiency of the various strains will reduce the uncritical use of unreliable results to support the use of melatonin deficient strains in melatonin research.

Patient-derived xenografts (PDX) are generated in immune deficient mice and demonstrate histologic and molecular features similar to their corresponding human tumors. However, murine tumors (non-human) spontaneously occur in these models. 120 consecutive patients with high-risk primary breast cancer enrolled in the prospective neoadjuvant BEAUTY study had tumor tissue obtained at the time of diagnosis. These tumor cells, including initial tissue and subsequent generations, were injected into either NSG (n = 365) or NOD-SCID (n = 396) female mice. Mice with initial tumor growth sufficient for transfer to the 2nd generation underwent histologic review by pathologists, including Ki67 staining. After passaging the tumors for up to 4 generations, at least one primary mouse tumor was detected from 24 of the 54 PDX-lines, for a frequency of 3.2% (24 mice out of 761 mice), including murine lymphomas (n = 13), mammary tumors (n = 7), osteosarcomas (n = 2), and hemangiosarcomas (n = 2). While true PDX showed scattered strong staining with Ki67, murine tumors were Ki67 negative. No significant differences (p = 0.062) were observed comparing development of murine tumors in NOD-SCID (n = 8) vs NSG mice (n = 16). While PDX are a useful tool in cancer research, there is a potential for spontaneous murine tumors to arise, which could alter results of studies utilizing PDX. Morphologic review by a pathologist, potentially along with Ki67 staining, is necessary to ensure that tumor growth represents the desired PDX prior to use in downstream studies. This study is the first prospective study evaluating the frequency, type, and time frame for development of non-human tumors.

Objectives: To investigate the anti-atherogenic effect of moxibustion and whether it is mediated through the reverse cholesterol transport process. Methods: 8-week-old male apolipoprotein E deficient (ApoE−/− knockout) mice were randomly divided into two groups (n=10 per group): atherosclerosis (AS) and AS plus moxibustion (AS+M). C57BL/6J mice of the same background (n=10) were selected as controls. Mice in the AS+M group received indirect moxibustion with an ignited moxa stick held over CV4. Mice of the AS and control groups were restrained in the same holder with an unlit moxa stick held over CV4. All treatments were performed for 20 min per day, 6 days per week for 12 weeks. After the treatment, the mice were euthanased and their serum lipids were measured. The aortic roots and thoracic aortas were collected for haematoxylin and eosin and red oil O staining, respectively, to analyse the atherosclerotic lesions. Expression of adenosine triphosphate binding cassette (ABCA)A1/G1 and liver X receptor α (LXRα) in the thoracic aorta were examined with Western blotting. Results: The moxibustion-treated (AS+M) mice showed a significantly lower plaque area percentage in the aortic root and thoracic aorta, and higher expression of LXRα and ABCA1 in the thoracic aorta compared with the AS mice. No significant differences were found in average lipid area percentage in the thoracic aorta, or ABCG1 expression in the thoracic aorta, between mice in the AS+M and AS groups. Conclusion: Moxibustion treatment at CV4 suppressed the progression of atherosclerotic lesions in ApoE−/− mice. The anti-atherogenic effect of moxibustion may be achieved by: (1) regulation of lipid metabolism, and thus prevention of lipid accumulation; and (2) upregulation of LXRα- and ABCA1-mediated cholesterol efflux in the lesion area.

International audience; Recent studies have revealed a possible link between the activities of polymorphic arylamine N-acetyltransferases (NATs) and energy metabolism. We used a Nat1/Nat2 double knockout (KO) mouse model to demonstrate that ablation of the two Nat genes is associated with modest, intermittent alterations in respiratory exchange rate. Pyruvate tolerance tests show that double KO mice have attenuated hepatic gluconeogenesis when maintained on a high-fat/high-sucrose diet. Absence of the two Nat genes also leads to an increase in the hepatic concentration of coenzyme A in mice fed a high-fat/high-sucrose diet. Our results suggest a modest involvement of NAT in energy metabolism in mice, which is consistent with the absence of major phenotypic deregulation of energy metabolism in slow human acetylators.

Aims Recent clinical studies demonstrated the association between myocardial infarction (MI) and osteoporotic fractures. We examined whether MI causes bone loss and the effects of exercise training on bone in mice after MI. Methods We created a MI model in 16-week-old male apolipoprotein E-deficient mice ( n = 42), which were randomly assigned to exercise group (MI-Ex) and sedentary group (MI-Sed). We also performed sham operations in other mice ( n = 10). Treadmill exercise training was performed from one week after operation to eight weeks. At eight weeks, the bone parameters of the femur were measured by quantitative computed tomography, followed by histological analysis ( n = 10–17). Results Bone mineral density (BMD) of the femur was significantly decreased in the MI-Sed group as compared with the sham group ( P Conclusions The present study demonstrates that MI reduces BMD and treadmill exercise training prevents the reduction of BMD in apolipoprotein E-deficient mice.