Multiple sclerosis (MS) is an inflammatory disease mainly affecting the central nervous system. In MS, abnormal immune mechanisms induce acute inflammation, demyelination, axonal loss, and the ...formation of central nervous system plaques. The long-term treatment involves options to modify the disease progression, whereas the treatment for the acute relapse has its focus in the administration of high-dose intravenous methylprednisolone (up to 1000 mg daily) over a period of three to five days as a first step. If symptoms of the acute relapse persist, it is defined as glucocorticosteroid-unresponsive, and immunomodulation by apheresis is recommended. However, several national and international guidelines have no uniform recommendations on using plasma exchange (PE) nor immunoadsorption (IA) in this case. A systematic review and meta-analysis was conducted, including observational studies or randomized controlled trials that investigated the effect of PE or IA on different courses of MS and neuromyelitis optica (NMO). One thousand, three hundred and eighty-three patients were included in the evaluation. Therapy response in relapsing-remitting MS and clinically isolated syndrome was 76.6% (95%CI 63.7-89.8%) in PE- and 80.6% (95%CI 69.3-91.8%) in IA-treated patients. Based on the recent literature, PE and IA may be considered as equal treatment possibilities in patients suffering from acute, glucocorticosteroid-unresponsive MS relapses.
After briefly discussing endothelial glycocalyx and its role in vascular physiology and renal disease, this overview focuses on its degradation very early in the course of microbial sepsis. We ...describe our recently proposed mechanism for glycocalyx degradation induced by exocytosis of lysosome-related organelles and release of their cargo. Notably, an intermediate in nitric oxide synthesis, NG-hydroxy-l-arginine, shows efficacy in curtailing exocytosis of these organelles and improvement in animal survival. These data not only depict a novel mechanism responsible for very early glycocalyx degradation, but may also outline a potential preventive therapy. The second issue discussed in this article is related to the therapeutic acceleration of restoration of already degraded endothelial glycocalyx. Here, using as an example our recent findings obtained with sulodexide, we illustrate the importance of the expedited repair of degraded endothelial glycocalyx for the survival of animals with severe sepsis. These two focal points of the review on glycocalyx may not only have broader disease applicability, but they may also provide additional evidence to buttress the idea of the importance of endothelial glycocalyx and its maintenance and repair in the prevention and treatment of an array of renal and nonrenal diseases.
Syndecan-4 (Synd4) is a member of the membrane-spanning, glycocalyx-forming proteoglycan family. It has been suggested that Synd4 participates in renal fibrosis. We compared wild-type and ...fibrosis-prone endothelial sirtuin 1-deficient (Sirt1
) mice, the latter being a model of global endothelial dysfunction. We performed mass spectrometry analysis, which revealed that Synd4 was highly enriched in the secretome of renal microvascular endothelial cells obtained from Sirt1
mice upon stimulation with transforming growth factor-β
; notably, all detectable peptides were confined to the ectodomain of Synd4. Elevated Synd4 was due to enhanced NF-κB signaling in Sirt1
mice, while its shedding occurred as a result of oxidative stress in Sirt1 deficiency. Synd4 expression was significantly enhanced after unilateral ureteral obstruction compared with contralateral kidneys. Furthermore, hyperplasia of renal myofibroblasts accompanied by microvascular rarefaction and overexpression of Synd4 were detected in Sirt1
mice. The ectodomain of Synd4 acted as a chemoattractant for monocytes with higher levels of macrophages and higher expression levels of Synd4 in the extracellular matrix of Sirt1
mice. In vitro, ectodomain application resulted in generation of myofibroblasts from cultured renal fibroblasts, while in vivo, subcapsular injection of ectodomain increased interstitial fibrosis. Moreover, the endothelial glycocalyx was reduced in Sirt1
mice, highlighting the induction of Synd4 occurring in parallel with the depletion of its intact form and accumulation of its ectodomain in Sirt1
mice. On the basis of our experimental results, we propose that it is the Synd4 ectodomain per se that is partially responsible for fibrosis in unilateral ureteral obstruction, especially when it is combined with endothelial dysfunction. NEW & NOTEWORTHY Our findings suggest that endothelial dysfunction induces the expression of syndecan-4 via activation of the NF-κB pathway. Furthermore, we show that syndecan-4 is shed to a greater amount because of increased oxidative stress in dysfunctional endothelial cells and that the release of the syndecan-4 ectodomain leads to tubulointerstitial fibrosis.
HMGB1 redox during sepsis Abdulmahdi, Wasan; Patel, Devika; Rabadi, May M. ...
Redox biology,
10/2017, Letnik:
13, Številka:
C
Journal Article
Recenzirano
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During sepsis, the alarmin HMGB1 is released from tissues and promotes systemic inflammation that results in multi-organ damage, with the kidney particularly susceptible to injury. The severity of ...inflammation and pro-damage signaling mediated by HMGB1 appears to be dependent on the alarmin's redox state. Therefore, we examined HMGB1 redox in kidney cells during sepsis. Using intravital microscopy, CellROX labeling of kidneys in live mice indicated increased ROS generation in the kidney perivascular endothelium and tubules during lipopolysaccharide (LPS)-induced sepsis. Subsequent CellROX and MitoSOX labeling of LPS-stressed endothelial and kidney proximal tubule cells demonstrated increased ROS generation in these cells as sepsis worsens. Consequently, HMGB1 oxidation increased in the cytoplasm of kidney cells during its translocation from the nucleus to the circulation, with the degree of oxidation dependent on the severity of sepsis, as measured in in vivo mouse samples using a thiol assay and mass spectrometry (LC-MS/MS). The greater the oxidation of HMGB1, the greater the ability of the alarmin to stimulate pro-inflammatory cyto-/chemokine release (measured by Luminex Multiplex) and alter mitochondrial ATP generation (Luminescent ATP Detection Assay). Administration of glutathione and thioredoxin inhibitors to cell cultures enhanced HMGB1 oxidation during sepsis in endothelial and proximal tubule cells, respectively. In conclusion, as sepsis worsens, ROS generation and HMGB1 oxidation increases in kidney cells, which enhances HMGB1's pro-inflammatory signaling. Conversely, the glutathione and thioredoxin systems work to maintain the protein in its reduced state.
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•Endotoxins (LPS) increase cellular oxidative stress during sepsis.•During its translocation, HMGB1 gets oxidized in the cytoplasm.•Thioredoxin and glutathione keep HMGB1 in a reduced redox state during sepsis.•HMGB1 oxidation enhances its stimulation of inflammatory cyto-/chemokine release.
Sirtuins (SIRT) are ubiquitous histone and protein deacetylases and a member of this family, SIRT1, is the best-studied one. Its functions in endothelial cells encompass branching angiogenesis, ...activation of endothelial nitric oxide synthase, regulation of proapoptotic and proinflammatory pathways, among others. Defective SIRT1 activity has been described in various cardiovascular, renal diseases and in aging-associated conditions. Therefore, understanding of SIRT1-deficient, endothelial dysfunctional phenotype has much to offer clinically. Here, we summarize recent studies by several investigative teams of the characteristics of models of global endothelial SIRT1 deficiency, the causes of facilitative development of fibrosis in these conditions, dissect the protein composition of the aberrant secretome of SIRT1-deficient endothelial cells and present several components of this aberrant secretome that are involved in fibrogenesis via activation of fibroblasts to myofibroblasts. These include ligands of Wnt and Notch pathways, as well as proteolytic fragments of glycocalyx core protein, syndecan-4. The latter finding is crucial for understanding the degradation of glycocalyx that accompanies SIRT1 deficiency. This spectrum of abnormalities associated with SIRT1 deficiency in endothelial cells is essential for understanding the origins and features of endothelial dysfunction in a host of cardiovascular and renal diseases.
Uncontrolled hypertension is a main risk factor for cardiovascular morbidity. Baroreflex activation therapy (BAT) is an effective therapy option addressing true resistant hypertension. We evaluated ...patients’ eligibility for BAT in a staged assessment as well as adherence to antihypertensive drug therapy. Therefore, we analyzed files of 345 patients, attending the hypertension clinic at University Medicine Göttingen. Additionally, gas chromatographic‐mass spectrometric urine analyses of selected individuals were performed evaluating their adherence. Most common cause for a revoked BAT recommendation was blood pressure (BP) control by drug adjustment (54.2%). Second leading cause was presence of secondary hypertension (31.6%). Patients to whom BAT was recommended (59 (17.1%)) were significantly more often male (67.8% vs. 43.3%, P = .0063), had a higher body mass index (31.8 ± 5.8 vs. 30.0 ± 5.7 kg/m², P = .0436), a higher systolic office (168.7 ± 24.7 vs. 147.7 ± 24.1 mmHg, P < .0001), and 24h ambulatory BP (155.0 ± 14.6 vs. 144.4 ± 16.8 mmHg, P = .0031), took more antihypertensive drugs (5.8 ± 1.3 vs. 4.4 ± 1.4, P < .0001), and suffered more often from numerous concomitant diseases. Eventually, 27 (7.8%) received a BAT system. In the toxicological analysis of 75 patients, mean adherence was 75.1%. 16 patients (21.3%) showed non‐adherence. Thus, only a small number of patients eventually received a BAT system, as treatable reasons for apparently resistant hypertension could be identified frequently. This study is—to our knowledge—the first report of a staged assessment of patients’ suitability for BAT and underlines the need for a careful examination and indication. Non‐adherence was proven to be a relevant issue concerning apparently resistant hypertension and therefore non‐eligibility for interventional antihypertensive therapy.
We evaluated the eligibility for baroreflex activation therapy (BAT) of 345 patients, attending the hypertension clinic at University Medicine Göttingen. Patients’ drug adherence was investigated by 75 toxicological analyses. Most common cause for a revoked BAT recommendation was blood pressure control by drug adjustment. Eventually, only less patients (7.8%) received a BAT system. Patients receiving a BAT recommendation showed specific characteristics and suffered numerous comorbidities, leading to a high cardiovascular risk, and therefore seem to greatly benefit from BAT implantation. 21.3% of patients showed non‐adherence, proving non‐adherence to be a relevant issue.
(1) Background: Arterial hypertension (HTN) is one of the most relevant cardiovascular risk factors. Nowadays multiple pharmaceutical treatment options exist with novel interventional methods (e.g., ...baroreflex activation therapy (BAT)) as a last resort to treat patients with resistant HTN. Although pathophysiology behind resistant HTN is still not fully understood. There is evidence that selected biomarkers may be involved in the pathophysiology of HTN. (2) Methods: We investigated serum SDC4-levels in patients suffering from resistant HTN before and 6 months after BAT implantation. We collected 19 blood samples from patients with resistant HTN and blood pressure above target and measured serum SDC4-levels. (3) Results: Our results showed high serum SDC4-levels in patients with resistant HTN as compared to a healthy population. Patients with both, resistant HTN and diabetes mellitus type II, demonstrated higher serum SDC4-levels. β-blockers had lowering effects on serum SDC4-levels, whereas calcium channel blockers were associated with higher levels of serum SDC4. BAT implantation did not lead to a significant difference in serum SDC4-levels after 6 months of therapy. (4) Conclusion: Based on our results we propose SDC4 is elevated in patients suffering from resistant HTN. Thus, SDC4 might be a potential marker for endothelial dysfunction in patients with resistant hypertension.
Estrogen and progesterone hormones are key regulators of a wide variety of biological processes. In addition to their influence on reproduction, cell differentiation and apoptosis, they affect ...inflammatory response, cell metabolism and most importantly, they regulate physiological breast tissue proliferation and differentiation as well as the development and progression of breast cancer. In order to assess whether genetic variants in the steroid hormone receptor gene ESR1 (estrogen receptor alpha) had an effect on sporadic breast cancer susceptibility, we assessed 7 ESR1 single nucleotide polymorphisms (SNPs) for associations with breast cancer susceptibility and clinical parameters in 221 breast cancer patients and 221 controls, respectively. We identified ESR1 intron SNP +2464 C/T (rs3020314) and ESR1 intron SNP -4576 A/C (rs1514348) to correlate with breast cancer susceptibility and progesterone receptor expression status. Patients genotyped CT for ESR1 intron SNP +2464 (rs3020314) (p ≤ 0.045) or genotyped AC for ESR1 intron SNP -4576 (rs1514348) (p ≤ 0.000026) were identified to carry a significant risk as to the development of breast cancer in the Central European Caucasian population (both together: p ≤ 0.000488). Our study could confirm previous associations and revealed new associations of SNP rs1514348 with susceptibility to breast cancer and clinical outcome, which might be used as new additional SNP markers.
Dysfunctional endothelial cells are an essential contributor to the progression of diverse chronic cardiovascular, renal, and metabolic diseases. It manifests in impairment of nitric oxide-dependent ...vasorelaxation, vascular permeability, and leukocytes deterrent. While endothelial glycocalyx is known to regulate these functions, glycocalyx has been shown to be impaired in pathologic settings leading to endothelial dysfunction. Are these findings coincidental or are they indicative of a potential cooperation of the glycocalyx and the endothelium in inducing a dysfunctional phenotype? The main thrust of this overview is to advance a hypothesis on the existence of vicious circle relations between impaired endothelial glycocalyx and endothelial cell dysfunction. We briefly introduce physiology and pathology of blood flow-induced components of mechanotransduction in endothelial cells, as this function is dependent on glycocalyx and is critically involved in the development of endothelial dysfunction. Next, we present a series of experimental findings and arguments favoring the view on the impairment of mechanotransduction in dysfunctional endothelia. We advance the concept of feedback reinforcement between perturbed endothelial glycocalyx and progression of endothelial dysfunction and sketch therapeutic approaches to restore them. Among those we introduce our recently designed liposomal nanocarriers of preassembled glycocalyx and present evidence of their ability to expeditiously restore endothelial mechanotransduction.
•Endothelial cell dysfunction is the bedrock of diverse cardiovascular, renal, and metabolic diseases.•Degraded endothelial glycocalyx and impaired mechanotransduction are manifestations of endothelial dysfunction.•The pathways connecting endothelial dysfunction with the degradation of glycocalyx are mutually reinforced. Such a conceptual link renders therapeutic benefits.•Existing strategies to restore glycocalyx and/or ameliorate endothelial dysfunction.•Recent findings with liposomal nanocarriers of the preassembled glycocalyx, which engender a dual effect of regenerating endothelial glycocalyx and improving endothelial mechanotransduction and nitric oxide production.
Sirtuin 1 and endothelial glycocalyx Lipphardt, Mark; Song, Jong Wook; Goligorsky, Michael S
Pflügers Archiv,
08/2020, Letnik:
472, Številka:
8
Journal Article
Recenzirano
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Sirtuin1 deficiency or reduced activity comprises one of the hallmarks of diseases as diverse as chronic cardiovascular, renal, and metabolic, some malignancies, and infections, as well as ...aging-associated diseases. In a mouse model of endothelium-limited defect in sirtuin 1 deacetylase activity, we found a dramatic reduction in the volume of endothelial glycocalyx. This was associated with the surge in the levels of one of key scaffolding heparan sulfate proteoglycans of endothelial glycocalyx, syndecan-4, and specifically, its extracellular domain (ectodomain). We found that the defect in endothelial sirtuin 1 deacetylase activity is associated with (a) elevated basal and stimulated levels of superoxide generation (via the FoxO1 over-acetylation mechanism) and (b) increased nuclear translocation of NF-kB (via p65 over-acetylation mechanism). These findings laid the foundation for the proposed novel function of sirtuin 1, namely, the maintenance of endothelial glycocalyx, particularly manifest in conditions associated with sirtuin 1 depletion. In the forthcoming review, we summarize the emerging conceptual framework of the enhanced glycocalyx degradation in the states of defective endothelial sirtuin 1 function, thus explaining a broad footprint of the syndrome of endothelial dysfunction, from impaired flow-induced nitric oxide production, deterrent leukocytes infiltration, increased endothelial permeability, coagulation, and pro-inflammatory changes to development of microvascular rarefaction and progression of an underlying disease.