New Aspects on the Role of Blood Pressure and Arterial Stiffness in Mechanical Assistance by Intra-aortic Balloon Pump: In-vitro Data and Their Application in Clinical Practice

Abstract BACKGROUND: Intestinal Graft-versus-Host disease is a frequent and often lethal complication after allogenic stem cell transplantation. Since NOD2 polymorphisms have been recognized as potential triggers of severe intestinal GvHD in humans, we have developed murine transplantation models to investigate the role of different pattern recognition receptors (PRR) in GvHD and GvL. Here we report our results on the role of TLR2 and TLR4 for the induction of GvHD. METHODS: Severity of GvHD in wildtype (wt) C57B/10 (H-2Db), TLR2−/−, TLR4−/−, and combined TLR2−/−TLR4−/− C57B/10 mice was investigated. Mice received treosulfan 2000 mg/kg from day -3 to -1 and cyclophosphamide 200 mg/kg day -1 prior to injection of 10×10^6 H-2Dd BM cells and 5×10^6 splenocytes (SC). Survival and GvHD score were assessed daily. Engraftment was determined every 2 weeks in pB and at the end of the experiments in bone marrow by flow cytometry. T cell alloreactivity in GvH direction was assessed by MLR using splenocytes as stimulators from PRR-deficient mice or wt as control and CFSE-staining as read-out. The relevance of PRR ligands for the enhancement of GvH alloreactivity was determined by addition of lipid A, lipopetides, or CpG. RESULTS: in vivo data: The transfer of 10×10^6 BMC + 5×10^6 SC induced a severe GvHD in all wt recipients, leading to death of 90% of the animals within 20 days. Recipient mice lacking either TLR2 or TLR4 showed only a slightly and not significantly decreased GvHD lethality. In recipients lacking both PPRs, i.e. TLR2 and TLR4, GvHD was generally milder and the majority (60%) of the animals survived until day 20 (p<0.05). However, the long term survival was not significantly improved. Differences in clinical severity of GvHD were confirmed histologically. In vitro data: Stimulation with cells from TLR2−/− and TLR4−/− mice resulted in a decreased alloreactivity in MLR. A median of 2% of Balb/c CD4+ T cells proliferated in response to C57B/10 stimulators. The addition of the TLR2 and TLR4 ligands lipopeptide, Lipid A and CpG significantly (p<0.05) increased the proliferation of CD4+ T cells in a specific manner more than twofold. CONCLUSION: Our in vivo and in vitro data consistantly show that bacterial components are involved in triggering GvH alloreactivity via different types of PPRs. Binding of bacterial substances to TLR2 and TLR4 leads to activation of the immune system and subsequent induction of GvHD. Our data provide an experimental basis for the development of strategies for modulation of the intestinal gut flora by selective gut decontamination and/or probiotic regimens to prevent GvHD in humans.

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α-Synuclein modulates tau spreading in mouse brains

Journal of Experimental Medicine ◽

10.1084/jem.20192193 ◽

2020 ◽

Vol 218 (1) ◽

Cited By ~ 1

Author(s):

Fares Bassil ◽

Emily S. Meymand ◽

Hannah J. Brown ◽

Hong Xu ◽

Timothy O. Cox ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Parkinson’S Disease ◽

Alzheimer's Disease ◽

Synergistic Effects ◽

Tau Pathology ◽

Vitro Data ◽

In Vitro Data

α-Synuclein (α-syn) and tau aggregates are the neuropathological hallmarks of Parkinson’s disease (PD) and Alzheimer’s disease (AD), respectively, although both pathologies co-occur in patients with these diseases, suggesting possible crosstalk between them. To elucidate the interactions of pathological α-syn and tau, we sought to model these interactions. We show that increased accumulation of tau aggregates occur following simultaneous introduction of α-syn mousepreformed fibrils (mpffs) and AD lysate–derived tau seeds (AD-tau) both in vitro and in vivo. Interestingly, the absence of endogenous mouse α-syn in mice reduces the accumulation and spreading of tau, while the absence of tau did not affect the seeding or spreading capacity of α-syn. These in vivo results are consistent with our in vitro data wherein the presence of tau has no synergistic effects on α-syn. Our results point to the important role of α-syn as a modulator of tau pathology burden and spreading in the brains of AD, PDD, and DLB patients.

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Endothelial-derived extracellular microRNA-92a promotes arterial stiffness by regulating phenotype changes of vascular smooth muscle cells

Scientific Reports ◽

10.1038/s41598-021-04341-1 ◽

2022 ◽

Vol 12 (1) ◽

Author(s):

Chen Wang ◽

Haoyu Wu ◽

Yuanming Xing ◽

Yulan Ye ◽

Fangzhou He ◽

...

Keyword(s):

Blood Pressure ◽

Smooth Muscle ◽

Arterial Stiffness ◽

Vascular Smooth Muscle ◽

Vascular Endothelial Cells ◽

Locked Nucleic Acid ◽

Vascular Endothelial ◽

Ang Ii

AbstractEndothelial dysfunction and vascular smooth muscle cell (VSMC) plasticity are critically involved in the pathogenesis of hypertension and arterial stiffness. MicroRNAs can mediate the cellular communication between vascular endothelial cells (ECs) and neighboring cells. Here, we investigated the role of endothelial-derived extracellular microRNA-92a (miR-92a) in promoting arterial stiffness by regulating EC–VSMC communication. Serum miR-92a level was higher in hypertensive patients than controls. Circulating miR-92a level was positively correlated with pulse wave velocity (PWV), systolic blood pressure (SBP), diastolic blood pressure (DBP), and serum endothelin-1 (ET-1) level, but inversely with serum nitric oxide (NO) level. In vitro, angiotensin II (Ang II)-increased miR-92a level in ECs mediated a contractile-to-synthetic phenotype change of co-cultured VSMCs. In Ang II-infused mice, locked nucleic acid-modified antisense miR-92a (LNA-miR-92a) ameliorated PWV, SBP, DBP, and impaired vasodilation induced by Ang II. LNA-miR-92a administration also reversed the increased levels of proliferative genes and decreased levels of contractile genes induced by Ang II in mouse aortas. Circulating serum miR-92a level and PWV were correlated in these mice. These findings indicate that EC miR-92a may be transported to VSMCs via extracellular vesicles to regulate phenotype changes of VSMCs, leading to arterial stiffness.

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Specific requirements for the ER to Golgi transport of GPI-anchored proteins in yeast

Journal of Cell Science ◽

10.1242/jcs.110.21.2703 ◽

1997 ◽

Vol 110 (21) ◽

pp. 2703-2714 ◽

Cited By ~ 6

Author(s):

C. Sutterlin ◽

T.L. Doering ◽

F. Schimmoller ◽

S. Schroder ◽

H. Riezman

Keyword(s):

Gpi Anchor ◽

Cellular Processes ◽

Golgi Transport ◽

Ceramide Synthesis ◽

Membrane Attachment ◽

Precise Role ◽

Vitro Data ◽

In Vitro Data

GPI-anchored proteins are attached to the membrane via a glycosylphosphatidylinositol-(GPI) anchor whose carbohydrate core is conserved in all eukaryotes. Apart from membrane attachment, the precise role of the GPI-anchor is not known, but it has been proposed to play a role in protein sorting. We have investigated the transport of the yeast GPI-anchored protein Gas1p. We identified two mutant strains involved in very different cellular processes that are blocked selectively in the transport of GPI-anchored proteins before arrival to the Golgi. The end8-1/lcb1-100 mutant is defective in ceramide synthesis. In vitro data suggest a requirement for ceramides after the exit from the ER. We therefore propose that ceramides might function in the fusion of a GPI-containing vesicle with the Golgi, but we cannot exclude a role in the ER. The second mutant that blocks the transport of GPI-anchored proteins to the Golgi is ret1-1, a mutant in the alpha-subunit of coatomer. In both mutants, GPI-anchor attachment is normal and in ret1-1 cells, the GPI-anchors are remodeled with ceramide to the same extent as in wild-type cells.

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LBD Dimerization of the Androgen Receptor but Not N/C Interaction Is Crucial for Normal Male Development in Mice

Journal of the Endocrine Society ◽

10.1210/jendso/bvab048.1675 ◽

2021 ◽

Vol 5 (Supplement_1) ◽

pp. A822-A822

Author(s):

Sarah El Kharraz ◽

Christine Helsen ◽

Vanessa Dubois ◽

Claude Libert ◽

Matti Poutanen ◽

...

Keyword(s):

Androgen Receptor ◽

Binding Domain ◽

Bone Homeostasis ◽

Bone Phenotype ◽

Male Development ◽

Vitro Data ◽

In Vitro Data

Abstract The androgen receptor (AR) is a nuclear receptor with a main role in the development and maintenance of the male phenotype. To execute its role as transcription factor, the AR forms homodimers. Three dimerization modes have been described for the AR: one via the DNA binding domain, a second via the ligand binding domain (LBD) and a third via interactions between the LBD and the aminoterminus of the AR (N/C). Based exclusively on in vitro data, all three dimerization modes seem to contribute to full AR activity, albeit to a different extent. The in vivo role of the dimerization modes, however, remains unknown. To study the physiological relevance, we generated two mouse models using a CRISPR/Cas9 approach, in which either the N/C interaction (ARNoC) or LBD dimerization (ARLmon) was disrupted. Surprisingly, the male ARNoC mice have a normal phenotype, indicating that the N/C interaction is not crucial for male development. In contrast, ARLmon males have an external female phenotype with cryptorchid testes and high levels of circulating testosterone (T), androstenedione and luteinizing hormone (LH) (6-, 13- and 45-fold higher, respectively). They have no prostate, seminal vesicles or epididymis, illustrating the importance of LBD dimerization during male development. Phenotyping the ARLmon model furthermore provided evidence of a crucial role for the AR in bone homeostasis as well as steroidogenesis. The ARLmon males display a severe bone phenotype, similar to that of complete AR knockout (ARKO) mice. The bone phenotype of ARKO was postulated to be mainly due to lower estrogen levels. However, in contrast to ARKO mice, ARLmon mice have high circulating levels of T, which can still function as prohormone for estradiol and support bone function via the ERα. Immunohistological analysis of ARLmon testes showed hyperplasia of the Leydig cells and residual spermatogenesis. Analysis of the steroidogenic pathway revealed that while the expression of most genes is increased, the expression of Hsd17b3, encoding the enzyme responsible for conversion of androstenedione into T, is low in ARLmon testis. Reporter assays confirmed that the promotor of this gene is indeed upregulated by the AR itself. In conclusion, our work uncovers the physiological role of the N/C interaction and LBD dimerization of the AR. It furthermore demonstrates a direct role for AR in male bone development independent of T aromatization into estrogens. Finally, we show that the AR controls the final step in the synthesis of its own ligand. In contrast to the in vitro data, N/C interaction is not crucial for male development in vivo. The ARLmon model illustrates that LBD dimerization could be an excellent new therapeutic target for inhibiting AR activity for example in advanced prostate cancer that has developed resistance to the current AR-targeting therapies.

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Role of Selective HDAC6 Inhibition On Multiple Myeloma Bone Disease

Blood ◽

10.1182/blood.v120.21.328.328 ◽

2012 ◽

Vol 120 (21) ◽

pp. 328-328

Author(s):

Loredana Santo ◽

Diana Cirstea ◽

Bin Wang ◽

Tso-Pang Yao ◽

Joy Y. Wu ◽

...

Keyword(s):

Mrna Expression ◽

Board Of Directors ◽

Cell Lines ◽

Bone Disease ◽

Research Funding ◽

Advisory Committees ◽

Vitro Data ◽

In Vitro Data

Abstract Abstract 328 In multiple myeloma (MM), deregulated osteoclast (OC)/osteoblast (OB) cross-talk induces osteolytic bone lesions. The HDAC6 selective inhibitor, rocilinostat (ACY-1215), in combination with bortezomib has shown potent anti myeloma activity in preclinical studies, which provided the rationale for a clinical trial that is currently recruiting relapsed/refractory MM patients (NCT01323751). However, while the beneficial role of bortezomib in tumor-related bone disease has been previously described, the effect of HDAC6 inhibition is not known. Evidence suggests a positive effect on bone turnover as pan HDAC inhibitors accelerate OB maturation and suppress OC maturation in vitro. Here, we evaluated effects of the selective HDAC6 inhibitor rocilinostat (Acetylon Pharmaceuticals, Inc), alone and in combination with bortezomib in MM bone disease. Rocilinostat (1 μM) alone and in combination with bortezomib (2.5 nM) inhibited OC differentiation, evidenced by a decreased number of TRAP positive multinucleated cells and bone-resorbing activity. In addition, rocilinostat (1 μM) significantly decreased cell growth of mature OC in co-culture with MM cell lines and in combination with bortezomib inhibited transcription factors implicated in OC differentiation including p-ERK, p-AKT, c-FOS, and NFATC1. Importantly, such an effect was cytokine (RANKL and M-CSF) dependent. Further, rocilinostat, alone and in combination, enhanced OB differentiation, evidenced by increased alkaline phosphatase (ALP) enzyme activity and alizarin red staining. In addition, we found increased mRNA expression of beta-catenin, osteocalcin, ALP, and RUNX2. Based on this promising in vitro data, we used the xenograft model of disseminated human MM in SCID mice to study the effect of rocilinostat, alone and in combination with bortezomib, on MM bone disease. MM.1S-GFP-Luc cells were injected intravenously, and MM disease progression was followed by bioluminescence imaging. A significant decrease in tumor burden was observed in mice following three weeks of treatment with rocilinostat, alone or in combination with bortezomib. Isolating serum from control and treated mice, we also observed a significant decrease of TRAPc5b levels, a marker of bone resorption, as well as a significant increase in osteocalcin levels, a marker of bone formation, in the serum of the combination treated cohort. Cells isolated from the calvaria from the combination treated group compared to the control group showed a significant increase in the mRNA expression of ALP, RUNX2, and osterix, as well as a significant decrease in the mRNA expression ratio of RANKL/OPG. To elucidate the role of HDAC6 inhibition on bone turnover, we used HDAC6 knockout mice. Cells were isolated from femurs, tibia, and spine of 2 month-old wild type (WT) and HDAC6 knockout (KO) mice and mRNA expression for osteocalcin, ALP, RUNX2 and osterix was assessed by qPCR. We observed a significant increase in osteocalcin mRNA expression without significant changes in the mRNA expression of ALP, RUNX2 and osterix. Bone marrow stromal cells (BMSCs) differentiated from WT and KO mice were co-cultured with MM murine cell lines and, notably, the proliferative advantage conferred by BMSC isolated from HDAC6 KO mice to MM cell lines was significantly decreased compared to WT BMSCs. These data suggest that a microenviroment lacking HDAC6 reduces MM cell proliferation. Moreover, treatment with rocilinostat (1mM) for 24 h inhibited proliferation of MM cells cocultured with WT BMSCs to levels observed in MM cells cultured with KO BMSC lacking endogenous HDAC6. Finally, the effect of co-treatment with rocilinostat (1μM) and bortezomib (2.5 nM) on proliferation of MM cells co-cultured with WT-BMSC was similar to that observed when bortezomib was added to MM cells in cocultures with KO BMSC. In conclusion, the in vitro data and the in vivo results from the xenograft models of human MM in SCID mice, as well as data in the HDAC6 KO mice, indicate a potential beneficial role of HDAC6 inhibition on MM-related bone disease. We are currently performing dynamic and static histomorphometric analysis to confirm this effect on bone remodeling at the tissue level. These effects on bone remodeling are an added benefit for MM patients and will be assessed prospectively in our ongoing clinical trial. Disclosures: Hideshima: Acetylon: Consultancy. Anderson:Onyx: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Millennium: Membership on an entity's Board of Directors or advisory committees. Jones:Acetylon Pharmaceuticals, Inc.: Employment. Raje:Onyx: Consultancy; Celgene: Consultancy; Millennium: Consultancy; Acetylon: Research Funding; Amgen: Research Funding; Eli-Lilly: Research Funding.

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Microcalcifications Drive Breast Cancer Occurrence and Development by Macrophage-Mediated Epithelial to Mesenchymal Transition

International Journal of Molecular Sciences ◽

10.3390/ijms20225633 ◽

2019 ◽

Vol 20 (22) ◽

pp. 5633 ◽

Cited By ~ 9

Author(s):

Manuel Scimeca ◽

Rita Bonfiglio ◽

Erika Menichini ◽

Loredana Albonici ◽

Nicoletta Urbano ◽

...

Keyword(s):

Breast Cancer ◽

Calcium Oxalate ◽

Epithelial To Mesenchymal Transition ◽

Benign Lesions ◽

Mesenchymal Transition ◽

Cancer Occurrence ◽

Vitro Data ◽

In Vitro Data

Background: This study aims to investigate: (a) the putative association between the presence of microcalcifications and the expression of both epithelial-to-mesenchymal transition and bone biomarkers, (b) the role of microcalcifications in the breast osteoblast-like cells (BOLCs) formation, and (c) the association between microcalcification composition and breast cancer progression. Methods: We collected 174 biopsies on which we performed immunohistochemical and ultrastructural analysis. In vitro experiments were performed to demonstrate the relationship among microcalcification, BOLCs development, and breast cancer occurrence. Ex vivo investigations demonstrated the significant increase of breast osteoblast-like cells in breast lesions with microcalcifications with respect to those without microcalcifications. Results: In vitro data displayed that in the presence of calcium oxalate and activated monocytes, breast cancer cells undergo epithelial to mesenchymal transition. Also, in this condition, cells acquired an osteoblast phenotype, thus producing hydroxyapatite. To further confirm in vitro data, we studied 15 benign lesions with microcalcification from patients that developed a malignant condition in the same breast quadrant. Immunohistochemical analysis showed macrophages’ polarization in benign lesions with calcium oxalate. Conclusions: Altogether, our data shed new light about the role of microcalcifications in breast cancer occurrence and progression.

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Induction of hepatic metallothionein by intraperitoneal metal injection: an associated inflammatory response

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1990.258.6.g926 ◽

1990 ◽

Vol 258 (6) ◽

pp. G926-G933 ◽

Cited By ~ 4

Author(s):

J. C. Fleet ◽

K. A. Golemboski ◽

R. R. Dietert ◽

G. K. Andrews ◽

C. C. McCormick

Keyword(s):

Inflammatory Response ◽

Messenger Rna ◽

Organic Complexes ◽

Ionic Nature ◽

Hepatic Metallothionein ◽

Rna Accumulation ◽

Vitro Data ◽

In Vitro Data

The nature of hepatic metallothionein (MT) induction by several metals and its relationship to an inflammatory response was studied in chicks. Intraperitoneal (ip) injection of chromium (Cr), managanese, and iron (Fe) caused a much greater increase in hepatic MT (10.2-, 9.0-, and 6.8-fold) compared with cobalt and nickel (2.5- and 2.9-fold); thus not all transition metals are effective. Cr3+ caused markedly greater hepatic MT accumulation than Cr6+, suggesting that the ionic nature of the metal is an important factor. Small organic complexes of Fe (ferrous gluconate or lactate, 6.2-fold) caused significantly greater accumulation of hepatic MT than ferric dextran (1.4-fold), a large organic aggregate. In vitro data from chick hepatocytes and/or fibroblasts clearly indicated that Fe does not effect the induction of MT directly. The role of inflammation, as measured by recruitment of peritoneal exudate cells (PEC), was examined. Endotoxin (LPS), Sephadex (S), and Fe elicited significant elevations in PEC number at 24 h posttreatment (S), and Fe elicited significant elevations in PEC number at 24 h posttreatment (S = Fe greater than LPS much greater than control). The percentage of heterophils but not macrophages was significantly correlated with the accumulation and induction of hepatic MT. In a similar experiment with Cr, we demonstrated that Cr3+ but not Cr6+ stimulated MT messenger RNA accumulation and concomitant hetereophil infiltration at 3 h after injection. Our results indicate that the induction of hepatic MT by the parenteral administration of a number of metals is dependent on the chemical nature of the metal and is associated with an inflammatory response.

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Molecular mechanism of the repressive phase of the mammalian circadian clock

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2021174118 ◽

2020 ◽

Vol 118 (2) ◽

pp. e2021174118

Author(s):

Xuemei Cao ◽

Yanyan Yang ◽

Christopher P. Selby ◽

Zhenxing Liu ◽

Aziz Sancar

Keyword(s):

Circadian Clock ◽

Local Concentration ◽

Transcriptional Repressors ◽

In Vivo Experiments ◽

E Box ◽

Vitro Data ◽

In Vitro Data

The mammalian circadian clock consists of a transcription–translation feedback loop (TTFL) composed of CLOCK–BMAL1 transcriptional activators and CRY–PER transcriptional repressors. Previous work showed that CRY inhibits CLOCK–BMAL1-activated transcription by a “blocking”-type mechanism and that CRY–PER inhibits CLOCK–BMAL1 by a “displacement”-type mechanism. While the mechanism of CRY-mediated repression was explained by both in vitro and in vivo experiments, the CRY–PER-mediated repression in vivo seemed in conflict with the in vitro data demonstrating PER removes CRY from the CLOCK–BMAL1–E-box complex. Here, we show that CRY–PER participates in the displacement-type repression by recruiting CK1δ to the nucleus and mediating an increased local concentration of CK1δ at CLOCK–BMAL1-bound promoters/enhancers and thus promoting the phosphorylation of CLOCK and dissociation of CLOCK–BMAL1 along with CRY from the E-box. Our findings bring clarity to the role of PER in the dynamic nature of the repressive phase of the TTFL.

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