Dietary potassium (K+) supplementation is associated with a blood pressure (BP) lowering effect, but not all studies agree. Here we examined the effects of short and long-term K+ supplementation on BP in mice, whether differences depend on the accompanying anion or the sodium (Na+) intake and molecular alterations in the kidney that may underlie BP changes. Relative to the control diet, BP was higher in mice fed a high NaCl (1.57% Na+) for 7 weeks or 2 weeks with a K+-free diet. BP was highest on a K+-free/high NaCl diet. Commensurate with increased abundance and phosphorylation of the thiazide sensitive sodium-chloride-cotransporter (NCC) on the K+-free/high NaCl diet, BP returned to normal with thiazides. Three weeks of a high K+ diet (5% K+) increased BP (predominantly during night-time) independently of dietary Na+ or anion intake. Conversely, 4 days of KCl feeding reduced BP. Both feeding periods resulted in lower NCC levels, but increased levels of cleaved (active) α and γ subunits of the epithelial Na+ channel ENaC. The elevated BP after chronic K+ feeding was reduced by amiloride but not thiazide. Our results suggest that dietary K+ has an optimal threshold where it may be most effective for cardiovascular health.
Robert Little, Sathish K. Murali, Søren B. Poulsen, Paul R. Grimm, Adrienne Assmus, Lei Cheng, Jessica R. Ivy, Ewout J. Hoorn, Vladimir V. Matchkov, Paul A. Welling, Robert A. Fenton
Neutrophils (PMN) are the first immune responders to infection/injury playing a critical role in clearing invading microbes and promoting tissue repair. However, dysregulated trafficking of PMNs across mucosal surfaces is a pathological hallmark of numerous diseases characterized by persistent or intermittent bursts of mucosal inflammation. The critical final step in PMN trafficking into mucosal lined organs (including the lungs, kidneys, skin and gut) involves transepithelial migration (TEpM). The glycoprotein CD11b/CD18 is the predominant β2 integrin that mediates PMN TEpM. Furthermore, CD11b/CD18 also regulates key PMN inflammatory effector functions that are implicated in the pathogenesis of chronic mucosal inflammation including superoxide release and degranulation. Recent studies have shown that terminal Fucose and GlcNAc glycans on CD11b/CD18 can be targeted to reduce PMN trafficking across intestinal epithelium, highlighting the importance of glycosylation in regulating PMN inflammatory function in mucosal settings. Previous studies have also demonstrated that the most abundant terminal glycan on human and murine PMN is sialic acid (Sia). However, the role of Sia in regulating PMN epithelial influx and mucosal inflammatory function is not well understood. Here we demonstrate that inhibiting sialidase mediated removal of α2-3 linked Sia from CD11b/CD18 inhibits PMN migration across intestinal epithelium in vitro and in vivo. Sialylation was also found to regulate critical PMN inflammatory effector functions including degranulation and superoxide release. Finally, we demonstrate that sialidase inhibition reduces bacterial peptide mediated CD11b/CD18 activation in PMN and blocks downstream intracellular signaling mediated by Spleen tyrosine kinase (Syk) and p38 MAP kinase. Taken together, these data demonstrate that sialylated glycans on CD11b/CD18 represent novel targets for ameliorating PMN mediated tissue damage and reducing inflammation in mucosal inflammatory disorders.
Veronica Azcutia, Matthias Kelm, Dylan Fink, Richard D. Cummings, Asma Nusrat, Charles A. Parkos, Jennifer C. Brazil
Antisense oligonucleotide (AO)-mediated therapy is a promising strategy to treat several neurological diseases including spinal muscular atrophy (SMA). However, limited delivery to the central nervous system (CNS) with AOs administered intravenously or subcutaneously is a major challenge. Here we demonstrate a single subcutaneous administration of cell-penetrating peptide DG9 conjugated to an AO called phosphorodiamidate morpholino oligomers (PMOs) reaches the CNS and significantly prolonged the median survival compared to unconjugated PMO and R6G-PMO in a severe SMA mouse model. Treated mice exhibited significantly higher expression of full-length SMN2 expression (FL-SMN2) in both the CNS and systemic tissues compared to non-treated and unmodified AO-treated mice. The treatment ameliorated the atrophic musculature and improved breathing function accompanied by improved muscle strength and innervation at the neuromuscular junction with no signs of apparent toxicity. We also demonstrated DG9-conjugated PMO localizes in nuclei in the spinal cord and brain after subcutaneous injections. Our data identify DG9 peptide conjugation as a powerful way to improve the efficacy of AO-mediated splice modulation. Finally, DG9-PMO is a promising therapeutic option to treat SMA and other neurological diseases, overcoming the necessity for intrathecal injections and treating body-wide tissues without apparent toxicity.
Tejal Aslesh, Esra Erkut, Jun Ren, Kenji Rowel Q. Lim, Stanley Woo, Susan Hatlevig, Hong M. Moulton, Simon Gosgnach, John Greer, Rika Maruyama, Toshifumi Yokota
Vascular calcification (VC) is concomitant with atherosclerosis, yet it remains uncertain why rupture-prone high-risk plaques do not typically show extensive calcification. Intraplaque hemorrhage (IPH) deposits erythrocyte-derived cholesterol enlarging the necrotic core and promoting the high-risk plaque development. Pro-atherogenic CD163+ alternative macrophages engulf hemoglobin-haptoglobin (HH) complexes at IPH sites. However, their role in VC has never been examined. Here we show, in human arteries, the distribution of CD163+ macrophages correlates inversely with VC. In vitro experiments using vascular smooth muscle cells (VSMC) cultured with HH-exposed human macrophages supernatant (M(Hb)) reduced calcification, while arteries from ApoE-/-CD163-/- mice showed greater VC. M(Hb) supernatant-exposed VSMC showed activated NFκB, while blocking NFκB attenuated the anti-calcific effect of M(Hb) on VSMCs. CD163+ macrophages altered VC through NFκB-induced transcription of hyaluronan synthase (HAS), an enzyme which catalyzes the formation of the extracellular matrix glycosaminoglycan, hyaluronan, within VSMCs. M(Hb) supernatants enhanced HAS production in VSMC, while knocking-down HAS attenuated its anti-calcific effect. NFκB blockade in ApoE-/- mice reduced hyaluronan and increased VC. In human arteries, hyaluronan/HAS were increased in areas of CD163+ macrophage presence. Our findings highlight an important mechanism by which CD163+ macrophages inhibit VC through NFκB-induced HAS augmentation and thus promote the high-risk plaques development.
Atsushi Sakamoto, Rika Kawakami, Masayuki Mori, Liang Guo, Ka Hyun Paek, Jose Verdezoto Mosquera, Anne Cornelissen, Saikat Kumar B. Ghosh, Kenji Kawai, Takao Konishi, Raquel Fernandez, Daniela T. Fuller, Weili Xu, Aimee E. Vozenilek, Yu Sato, Hiroyuki Jinnouchi, Sho Torii, Adam W. Turner, Hirokuni Akahori, Salome Kuntz, Craig C. Weinkauf, Parker J. Lee, Robert Kutys, Kathryn Harris, Alfred Lawrence Killey, Christina M. Mayhew, Matthew Ellis, Leah M. Weinstein, Neel V. Gadhoke, Roma Dhingra, Jeremy Ullman, Endale Armelle Dikongue Emene, Maria E. Romero, Frank D. Kolodgie, Clint L. Miller, Renu Virmani, Aloke V. Finn
Reactivation of human cytomegalovirus (HCMV) from latency is a frequent complication following hematopoietic stem cell transplantation (HSCT). The development of acute graft-versus-host disease (GVHD) is a significant risk factor for HCMV disease. Using a murine GVHD model in animals latently infected with murine CMV (MCMV) we studied preventive and therapeutic interventions in this high-risk scenario of HSCT. Mice latently infected with MCMV reactivated MCMV and developed disseminated MCMV infection concomitant with the manifestations of GVHD. Dissemination was accompanied by accelerated mortality. We demonstrate that MCMV reactivation and dissemination was modulated by MCMV-specific antibodies, thus demonstrating in vivo protective activity of antiviral antibodies. However, the efficacy of serum therapy required repetitive doses of high titer immune serum secondary to the shortened serum half-life of IgG in animals with GvHD. In a complementary approach, treatment of GVHD by adoptive transfer of donor-derived regulatory T cells facilitated production of MCMV-specific antibodies from newly developing donor-derived B cells. Together, our findings strongly suggest that antibodies play a major role in controlling recurrent MCMV infection that follows GVHD and argue for reassessing the potential of antibody treatments as well as therapeutic strategies that enhance de novo antibody development against HCMV.
Martina Seefried, Nadine Hundhausen, Irena Kroeger, Maike Büttner-Herold, Petra Hoffmann, Matthias Edinger, Evelyn Ullrich, Friederike Berberich-Siebelt, William J. Britt, Michael Mach, Thomas H. Winkler
As the COVID-19 pandemic continues, long-term immunity against SARS-CoV-2 will be globally important. Official weekly cases have not dropped below 2 million since September of 2020, and continued emergence of novel variants have created a moving target for our immune systems and public health alike. The temporal aspects of COVID-19 immunity, particularly from repeated vaccination and infection, are less well understood than short-term vaccine efficacy. In this study, we explore the impact of combined vaccination and infection, also known as hybrid immunity, and the timing thereof on the quality and quantity of antibodies elicited in a cohort of 96 health care workers. We find robust neutralizing antibody responses among those with hybrid immunity against all variants, including Omicron BA.2, and significantly improved neutralizing titers with longer vaccine-infection intervals up to 400 days. These results indicate that anti-SARS-CoV-2 antibody responses undergo continual maturation following primary exposure by either vaccination or infection for at least 400 days after last antigen exposure. We show that neutralizing antibody responses improved upon secondary boosting with greater potency seen after extended intervals. Our findings may also extend to booster vaccine doses, a critical consideration in future vaccine campaign strategies.
Timothy A. Bates, Hans C. Leier, Savannah K. McBride, Devin Schoen, Zoe L. Lyski, David D. Xthona Lee, William B. Messer, Marcel E. Curlin, Fikadu G. Tafesse
BACKGROUND. Major depressive disorder (MDD) can benefit from novel interventions and personalization. Deep transcranial magnetic stimulation (Deep TMS) targeting the lateral prefrontal cortex (LPFC) using the H1 Coil, was FDA-cleared for treatment of MDD, however recent preliminary data indicate that targeting medial prefrontal cortex (MPFC) using the H7 Coil might induce as good or even better outcomes. Here we explored whether Deep TMS targeting the MPFC is non-inferior to targeting LPFC, and whether electrophysiological or clinical markers for patient selection can be identified. METHODS. The present prospective multicenter randomized study enrolled 169 MDD patients who failed antidepressant treatments in the current episode. Patients were randomized to receive 24 Deep TMS sessions over 6 weeks, using either the H1 Coil or the H7 Coil. The primary efficacy endpoint was the change from baseline to week 6 in the Hamilton-Depression-Rating-Scores. RESULTS. Clinical efficacy and safety profiles were similar and not significantly different between groups, with response rates of 60.9% for the H1 Coil and 64.2% for the H7 Coil. Moreover, brain activity measured by EEG during the first treatment session correlated with clinical outcomes in a coil-specific manner, and a cluster of baseline clinical symptoms was found to potentially distinguish between patients who can benefit from each Deep TMS target. CONCLUSION. This study provides a new treatment option for MDD, using the H7 Coil, and initial guidance to differentiate between patients likely to respond to LPFC versus MPFC stimulation targets, which require further validation studies. TRIAL REGISTRATION. ClinicalTrials.gov NCT03012724. FUNDING. Brainsway Ltd.
Abraham Zangen, Samuel Zibman, Aron Tendler, Noam Barnea-Ygael, Uri Alyagon, Daniel M. Blumberger, Geoffrey Grammer, Hadar Shalev, Tatiana Gulevsky, Tanya Vapnik, Alexander Bystritsky, Igor Filipčić, David Feifel, Ahava Stein, Frederic Deutsch, Yiftach Roth, Mark S. George
Bone metastases are a common complication of breast cancer. We have demonstrated that intermittent administration of parathyroid hormone (PTH [1-34]) reduces the incidence of bone metastases in murine models of breast cancer by acting on osteoblasts to alter the bone microenvironment. Here, we examined the role of PTH receptor (PTH1R)-mediated signaling in both osteoblasts and breast cancer cells in influencing bone metastases. In mice with impaired PTH1R signaling in osteoblasts, intermittent PTH did not reduce bone metastasis. Intermittent PTH also failed to reduce bone metastasis when expression of PTH1R was knocked down in 4T1 murine breast cancer cells by shRNA. In 4T1 breast cancer cells, PTH decreased expression of PTH-related protein (PTHrP), implicated in the vicious cycle of bone metastases. Knockdown of PTHrP in 4T1 cells significantly reduced migration towards MC3T3-E1 osteoblasts, and migration was further inhibited by treatment with intermittent PTH. Conversely, overexpression of PTHrP in 4T1 cells increased migration towards MC3T3-E1 osteoblasts and this was not inhibited by PTH. In conclusion, PTH1R expression is crucial in both osteoblasts and breast cancer cells for PTH to reduce bone metastases and in breast cancer cells this may be mediated in part by suppression of PTHrP.
Srilatha Swami, Hui Zhu, Aria Nisco, Takaharu Kimura, Matthew J. Kim, Vaisakh Nair, Joy Y. Wu
Most circulating endothelial cells are apoptotic, but rare circulating endothelial colony forming cells (C-ECFCs, also known as blood outgrowth endothelial cells (BOECs)) with proliferative and vasculogenic activity can be cultured; the origin and naïve function of these C-ECFCs remains obscure. Herein, detailed lineage tracing reveals murine C-ECFCs emerge in the early postnatal period, display high vasculogenic potential, with enriched frequency of clonal proliferative cells compared to tissue-resident ECFCs, and are not committed to or derived from the bone marrow hematopoietic system but from tissue-resident ECFCs. In human subjects, C-ECFCs are present in the CD34bright cord blood mononuclear subset, possess proliferative potential and in vivo vasculogenic function in a naïve or cultured state, and display a single cell transcriptome sharing some umbilical venous endothelial cell features like, higher Protein C Receptor and extracellular matrix gene expression. This study provides an advance for the field by identifying the origin, naïve function, and antigens to prospectively isolate C-ECFCs for translational studies.
Yang Lin, Kimihiko Banno, Chang-Hyun Gil, Jered Myslinski, Takashi Hato, W. Christopher Shelley, Hongyu Gao, Xiaoling Xuei, Yunlong Liu, David Basile, Momoko Yoshimoto, Nutan Prasain, Stefan P Tarnawsky, Ralf H. Adams, Katsuhiko Naruse, Junko Yoshida, Michael P. Murphy, Kyoji Horie, Mervin C. Yoder
Loss of function mutations in CCM genes and gain of function mutation in the MAP3K3 gene encoding MEKK3 cause cerebral cavernous malformation (CCM). Deficiency of CCM proteins leads to the activation of MEKK3-KLF2/4 signaling, but it is not clear how this occurs. Here we demonstrate that deletion of the CCM3 interacting kinases STK24/25 in endothelial cells cause defects in vascular patterning during development as well as CCM lesion formation during postnatal life. While permanent deletion of STK24/25 in endothelial cells caused developmental defects of the vascular system, inducible postnatal deletion of STK24/25 impaired angiogenesis in the retina and brain. More importantly, deletion of STK24/25 in neonatal mice led to the development of severe CCM lesions. At the molecular level, a hybrid protein consisting of the STK kinase domain and the MEKK3 interacting domain of CCM2 rescued the vascular phenotype caused by the loss of ccm gene function in zebrafish. Our study suggests that CCM2/3 proteins act as adapters to allow recruitment of STK24/25 to limit the constitutive MEKK3 activity that contributes to vessel stability. Loss of STK24/25 causes MEKK3 activation leading to CCM lesion formation.
Xi Yang, Shi-Ting Wu, Rui Gao, Rui Wang, Yixuan Wang, Zhenkun Dong, Lu Wang, Chunxiao Qi, Xiaohong Wang, M. Lienhard Schmitz, Renjing Liu, Zhiming Han, Lu Wang, Xiangjian Zheng
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