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Aims Hypoxia-induced adipokine release has been attributed mainly to HIF-1α. Here we investigate the role of intracellular calcium and NF-kB in the hypoxia-dependent release of leptin, VEGF, IL-6 and the hypoxia-induced inhibition of adiponectin release in human adipocytes. Main methods We used intracellular calcium imaging to compare calcium status in preadipocytes and in adipocytes. We subjected both cell types to hypoxic conditions and measured the release of adipokines induced by hypoxia in the presence and absence of HIF-1α inhibitor YC-1, NF-κB inhibitor SN50 and intracellular calcium chelator BAPTA-AM. Key findings We demonstrate reduced intracellular calcium oscillations and increased oxidative stress as the cells transitioned from preadipocytes to adipocytes. We show that differentiation of preadipocytes to adipocytes is associated with distinct morphological changes in the mitochondria. We also show that hypoxia-induced secretion of leptin, VEGF, IL-6 and hypoxia-induced inhibition of adiponectin secretion are independent of HIF-1α expression. The hypoxia-induced leptin, VEGF and IL-6 release are [Ca++]i dependent whereas adiponectin is NF-kB dependent. Significance Our work suggests a major role for [Ca++]i in preadipocyte differentiation to adipocytes and that changes in mitochondrial morphology in the adipocytes might underlie the reduced calcium oscillations observed in the adipocytes. It also demonstrates that multiple signaling pathways are associated with the hypoxia-induced adipokine secretion.

The data set presented here is associated with the article “Intracellular calcium and NF-kB regulate hypoxia-induced leptin, VEGF, IL-6 and adiponectin secretion in human adipocytes” (Al-Anazi et al., 2018). Data illustrate hypoxia-induced VEGF and leptin expression in human adipocytes treated with the calcium chelator BAPTA-AM (1 µM). It also shows NF-κB p65 induced expression by hypoxia. Preadipocytes were differentiated for 14 days and then subjected to 0.5–1.5% oxygen in the presence and absence of BAPTA-AM or the NF-κB inhibitor SN50 for 48 h prior to RNA isolation and PCR analysis.

β2-microglobulin (β2-m), a 11.8 kDa protein, pairs non-covalently with the α3 domain of the major histocompatibility class (MHC) I α-chain and is essential for the conformation of the MHC class I protein complex. Shed β2-m is measurable in circulation, and various disorders are accompanied by increases in β2-m levels, including several viral infections. Therefore, we explored whether β2-m levels could also be elevated in Coronavirus disease 2019 (Covid-19) and whether they predict disease severity. Serum β2-m levels were measured in a cohort of 34 patients infected with SARS-CoV-2 on admission to a tertiary care hospital in Riyadh, Saudi Arabia, as well as in an approximately age-sex matched group of 34 uninfected controls. Mean β2-m level was 3.25±1.68 mg/l (reference range 0.8–2.2 mg/l) in patients (mean age 48.2±21.6) and 1.98±0.61 mg/l in controls (mean age 48.2±21.6). 17 patients (mean age 36.9± 18.0) with mean β2-m levels of 2.27±0.64 mg/l had mild disease by WHO severity categorization, 12 patients (mean age 53.3±18.1) with mean β2-m levels of 3.57±1.39 mg/l had moderate disease, and five patients (of whom 2 died; mean age 74.4±13.8) with mean β2-m levels of 5.85±1.85 mg/l had severe disease (P < = 0.001, by ANOVA test for linear trend). In multivariate ordinal regression β2-m levels were the only significant predictor of disease severity. Our findings suggest that higher β2-m levels could be an early indicator of severity of disease and predict outcome of Covid-19. As the main limitations of the study are a single-center study, sample size and ethnicity, these results need confirmation in larger cohorts outside the Arabian Peninsula in order to delineate the value of β2-m measurements. The role of β2-m in the etiology and pathogenesis of severe Covid-19 remains to be elucidated.

Background Lipid metabolism dysfunction leading to excess fat deposits (obesity) may cause tumor (cancer) development. Both obesity and cancer are the epicenter of important medical issues. Lipid metabolism and cell death/proliferation are controlled by biochemical and molecular pathways involving many proteins, and organelles; alteration in these pathways leads to fat accumulation or tumor growth. Mammalian Kruppel-like factors, KLFs play key roles in both lipid metabolism and tumor development. Scope of review Substantial epidemiological and clinical studies have established strong association of obesity with a number of human cancers. However, we need more experimental verification to determine the exact role of this metabolic alteration in the context of tumor development. A clear understanding of molecules, pathways and the mechanisms involved in lipid metabolism and cell death/proliferation will have important implications in pathogenesis, and prevention of these diseases. Major conclusion The regulatory role of KLFs, in both cell death/proliferation and lipid metabolism suggests a common regulation of both processes. This provides an excellent model for delivering a precise understanding of the mechanisms linking altered expression of KLFs to obesity and tumor development. General significance Currently, mouse and rats are the models of choice for investigating disease mechanisms and pharmacological therapies but a genetic model is needed for a thorough examination of KLF function in vivo during the development of an organism. The worm Caenorhabditis elegans is an ideal model to study the connectivity between lipid metabolism and cell death/proliferation.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is characterized as inflammation of small-sized to medium-sized blood vessels and encompasses several clinicopathologic entities including granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis, and renal-limited ANCA-associated vasculitis. Over the past several decades, significant progress has been made in understanding the pathophysiology of ANCA-associated vasculitis. Although neutrophils contain a multitude of granular proteins, clinically significant autoantibodies are only recognized against myeloperoxidase and proteinase 3, both of which are present in the azurophilic granules. The propensity to develop these antibodies depends on a variety of predisposing factors such as microbial infection, genetic factors, environmental agents, and therapeutic drugs among others. These factors are usually associated with production of proinflammatory cytokines with capacity to prime the neutrophils. As a result a high proportion of neutrophils in circulation may be primed resulting in exposure of cytoplasmic proteins including myeloperoxidase and proteinase 3 on the surface of the neutrophils. Primed neutrophils are activated by interaction with ANCA in circulation. Activated neutrophils attach to and transmigrate through endothelium and accumulate within the vessel wall. These neutrophils degranulate and produce reactive oxygen radicals and ultimately die, causing tissue injury. Endothelial injury results in leakage of serum proteins and coagulation factors causing fibrinoid necrosis. B cells produce ANCAs, as well as neutrophil abnormalities and imbalances in different T-cell subtypes with excess of Th17, which perpetuate the inflammatory process.

BackgroundPulmonary fibrosis is one of the leading indications for lung transplantation. The disease, which is of unknown aetiology, can be progressive, resulting in distortion of the extracellular matrix (ECM), inflammation, fibrosis and eventual death.Methods13 patients born to consanguineous parents from two unrelated families presenting with interstitial lung disease were clinically investigated. Nine patients developed respiratory failure and subsequently died. Molecular genetic investigations were performed on patients' whole blood or archived tissues, and cell biological investigations were performed on patient-derived fibroblasts.ResultsThe combination of a unique pattern of early-onset lung fibrosis (at 12–15 years old) with distinctive radiological findings, including 1) traction bronchiectasis, 2) intralobular septal thickening, 3) shrinkage of the secondary pulmonary lobules mainly around the bronchovascular bundles and 4) early type 2 respiratory failure (elevated blood carbon dioxide levels), represents a novel clinical subtype of familial pulmonary fibrosis. Molecular genetic investigation of families revealed a hypomorphic variant in S100A3 and a novel truncating mutation in S100A13, both segregating with the disease in an autosomal recessive manner. Family members that were either heterozygous carriers or wild-type normal for both variants were unaffected. Analysis of patient-derived fibroblasts demonstrated significantly reduced S100A3 and S100A13 expression. Further analysis demonstrated aberrant intracellular calcium homeostasis, mitochondrial dysregulation and differential expression of ECM components.ConclusionOur data demonstrate that digenic inheritance of mutations in S100A3 and S100A13 underlie the pathophysiology of pulmonary fibrosis associated with a significant reduction of both proteins, which suggests a calcium-dependent therapeutic approach for management of the disease.

Background: Recent recommendations have established clinical remission ideally or low disease activity (LDA) as therapeutic targets in all patients with rheumatoid arthritis (RA). Controlled studies of biologic agents have primarily assessed treatment effects in patients with severe RA; patients with moderate disease activity, whoconstitute a larger group, have received far less attention. In Period 1 of the PRESERVE trial, the proportion of subjects with moderately active RA achieving LDA or remission were evaluated after treatment with etanercept 50mg once weekly (QW) plus methotrexate for 36 weeks.Methods: Subjects with DAS28 >3.2 and ≤5.1 despite stable doses of oral methotrexate received open-label etanercept 50mg QW plus methotrexate (screening dose permitted to be titrated up to 25 mg/wk through week 28) for 36 weeks.Results: 834 subjects received treatment and were analyzed. Subjects were mostly female (83%), Caucasian (74%), RFþ (73%), and aCCPþ (78%), with a mean age of 48 years and disease duration of 7 years. Mean baseline DAS28 was 4.4; SDAI, 19.1; ESR, 22.2 mm/hr; and CRP, 12.3 mg/L. Efficacy results from Period 1 are shown in the table. The most commonly reported adverse events (AEs) were headache (6.1%), nasopharyngitis (5.4%), and upper respiratory tract infection (4.4%). Twenty-two subjects (2.6%) discontinued due to AEs.Conclusions: Substantial proportions of subjects with moderately active RA who received etanercept 50mg QW plus methotrexate for 36 weeks achieved LDA (85%-86%), DAS28 remission (67%), or SDAI remission (25%). Therefore, these ambitious goals can be achieved realistically in a high percentage of patients with moderate disease activity.

We describe a flare of Behçet's syndrome in a 42-year-old man who presented with florid mucocutaneous manifestations, headache and vomiting, but without meningeal or neurologic signs. A single, non-enhancing cortical lesion was found in the frontal lobe by computed tomography and magnetic resonance (MR) imaging studies. Diffusion-weighted analysis and MR spectroscopy were consistent with focal inflammation. The patient improved with colchicine, and after 5 months, a repeat MR scan demonstrated resolution of the inflammatory changes suggesting that involvement of the cerebral cortex may be a self-limiting phenomenon, distinct from other more frequent and destructive parenchymal manifestations of neuro-Behçet's disease.

The molecular mechanisms underlying the geometrical changes of the left ventricle during the progression to heart failure and recovery are not well defined.Here we investigate the involvement of matrixins and cardiokines in an ovine model of pressure-induced left ventricular failure (LVF).Fifteen sheep underwent supracoronary aortic banding with an inflatable cuff. A controlled and progressive increase of LV pressure was monitored echocardiographically. Endomyocardial biopsies were collected throughout the development of LVF and subsequent recovery after pressure unloading.Thirteen sheep developed LVF with a subsequent recovery. Peak left ventricular hypertrophy (LVH) and dilatation (LVD) occurred at 31.5 ± 1.6 weeks and 102.7 ± 2.2 weeks post-banding respectively, with an increase in LV internal diameter in diastole (LVIDd 5.11 ± 0.12 compared to the control 3.37 ± 0.07 cm, p0.001), with preserved LV ejection fraction (LVEF). Reduced LVEF became evident 116.5 ± 2.7 weeks post-banding. Clinical and echocardiographic improvements were observed following deflation of the aortic banding cuff. By 138.1 ± 3.1 weeks cardiac performance recovered with restoration of LVEF. Significant changes in the expression of matrix metalloproteinases (MMP)-1, -2, -3, vascular endothelial cell growth factor (VEGF), fibroblast growth factor (FGF)-2, interferon (INF)-α-2 and soluble CD40 ligand (sCD40L) were observed throughout the progression to failure and recovery.We used an ovine model to study reversible LV remodelling without interruption and found significant changes in matrixin and cardiokine expression during LV progression to failure and recovery.

Purpose. To assess the accuracy of different MR sequences for the detection of articular cartilage abnormalities in rheumatoid arthritis. Design and patients. Ten metacarpophalangeal joints and 10 metatarsophalangeal joints (specimens from arthritis patients undergoing ablative joint surgery) were examined with a fat-suppressed (FS) 3D FLASH, a FS 3D FISP, a FS 2D fast spin-echo T2-weighted, and a 2D FS spin-echo T1-weighted sequence. Each cartilage lesion and each cortical lesion was graded from 0 to 4 (modified Outerbridge staging system). Subsequently, the results of each sequence were compared with the macroscopic findings and statistically tested against each other. Results. The study shows that 3D gradient-echo sequences with fat suppression were best for imaging and grading of cartilage lesions in arthritis of the small joints of the hands and feet. Using 3D techniques, all grade 2, grade 3, and grade 4 lesions of cartilage or cortical bone were detected. Conclusion. FS 3D gradient-echo techniques were best for the detection and grading of hyaline cartilage and subchondral bone lesions in rheumatoid arthritis. MRI has a great potential as an objective method of evaluating cartilage damage and bone erosions in rheumatoid arthritis.

We report a 57-year-old man with acute thrombocytopenia, leucopenia, and multiorgan dysfunction. Patient was from North Korea and was temporarily working in Dubai, United Arab Emirates, when he fell ill in March 2009. At the same time and unknown to us, many patients with similar clinical manifestations were admitted to hospitals in China. The Chinese cases—identified between March and July 2009—were recently reported to have been infected with a tick-born strain of bunyavirus, a new disease. The virus infection was documented in patients from central China and the region that shares the border with North Korea. The clinical manifestations, the time of disease onset, and geographical link of the patient with the region in which the disease is endemic suggest that the patient had SFTS bunyavirus infection.

Introduction A novel in vitro system was developed to measure O2 consumption by murine tissues over several hours. Methods Tissue specimens (7–35 mg) excised from male Balb/c mice were immediately immersed in ice-cold Krebs–Henseleit buffer, saturated with 95% O2:5% CO2. The specimens were incubated at 37 °C in the buffer, continuously gassed with O2:CO2 (95:5). [O2] was determined as a function of time from the phosphorescence decay rates (1 / τ) of Pd(II) meso-tetra-(4-sulfonatophenyl)-tetrabenzoporphyrin. The values of 1 / τ were linear with [O2]: 1 / τ = 1/τo + kq [O2]; 1 / τo = the decay rate for zero O2, kq = the rate constant in s−1 μM−1. Results NaCN inhibited O2 consumption, confirming oxidation occurred in the mitochondrial respiratory chain. The rate of respiration in lung specimens incubated in vitro for 3.9 ≤ t ≤ 12.4 h was 0.24 ± 0.03 μM O2 min−1 mg−1 (mean ± SD, n = 28). The corresponding rate for the liver was 0.27 ± 0.13 (n = 11, t ≤ 4.7 h), spleen 0.28 ± 0.07 (n = 10, t ≤ 5 h), kidney 0.34 ± 0.12 (n = 7, t ≤ 5 h) and pancreas 0.35 ± 0.09 (n = 10, t ≤ 4 h). Normal tissue histology at hour 5 was confirmed by light and electron microscopy. There was negligible number of apoptotic cells by caspase 3 staining. Discussion This approach allows accurate assessment of tissue bioenergetics in vitro.

In this study, we investigated the expression patterns of 15 matrix metalloproteinases (MMPs) and three tissue inhibitors of metalloproteinase in gliomas, medulloblastomas, and normal brain tissue. By Northern blot analysis we found increased levels of mRNAs encoding for gelatinase A, gelatinase B, two membrane-type MMPs (mt1- and mt2-MMP), and tissue inhibitors of metalloproteinase-1 in glioblastomas and medulloblastomas. We observed a significant increase of mt1-MMP, gelatinase A, gelatinase B, and tissue inhibitors of metalloproteinase-1 in glioblastomas as compared with low-grade astrocytomas, anaplastic astrocytomas, and normal brain. In medulloblastomas, the expression of mt1-MMP, mt2-MMP, and gelatinase A were also increased, but to a lesser extent than that observed in glioblastomas. These data were confirmed at the protein level by immunostaining analysis. Moreover, substrate gel electrophoresis showed that the activated forms of gelatinases A and B were present in glioblastomas and medulloblastomas. These results suggest that increased expression of mt1-MMP/gelatinase A is closely related to the malignant progression observed in gliomas. Furthermore, the present study demonstrates, to our knowledge for the first time, that medulloblastomas express high levels of MMP.

Numerous studies have reported on structural vascular anomalies and ischemia associated with neurofibromatosis type 1 that are thought to stem from dysfunction of neurofibromin, the neurofibromatosis type 1 protein. Documented cases of associated antiphospholipid syndrome fulfilling the accepted diagnostic criteria are exceptionally rare, with only three cases reported in the literature. Here, we report on a patient with neurofibromatosis type 1 and a history of spontaneous abortions presenting with sudden vision loss in the right eye and swelling of the optic nerve head. Fluorescein angiography indicated anterior ischemic optic neuropathy. Brain magnetic resonance imaging revealed findings consistent with left cavernous sinus meningioma. Serologic testing demonstrated persistently elevated anti-b2-glycoprotein antibodies. Her findings suggested antiphospholipid syndrome with concomitant clinical and laboratory evidence of antiphospholipid syndrome: frequent abortions, a vaso-occlusive episode, and persistently elevated antiphospholipid syndrome antibodies. To our knowledge, this case represents the first neuro-ophthalmic manifestation of antiphospholipid syndrome associated with neurofibromatosis type 1.

Lipid metabolic disorder is a critical risk factor for metabolic syndrome, triggering debilitating diseases like obesity and diabetes. Both obesity and diabetes are the epicenter of important medical issues, representing a major international public health threat. Accumulation of fat in adipose tissue, muscles and liver and/or the defects in their ability to metabolize fatty acids, results in insulin resistance. This triggers an early pathogenesis of type 2 diabetes (T2D). In mammals, lipid metabolism involves several organs, including the brain, adipose tissue, muscles, liver, and gut. These organs are part of complex homeostatic system and communicate through hormones, neurons and metabolites. Our study dissects the importance of mammalian Krüppel-like factors in over all energy homeostasis. Factors controlling energy metabolism are conserved between mammals and Caenorhabditis elegans providing a new and powerful strategy to delineate the molecular pathways that lead to metabolic disorder. The C. elegans intestine is our model system where genetics, molecular biology, and cell biology are used to identify and understand genes required in fat metabolism. Thus far, we have found an important role of C. elegans KLF in FA biosynthesis, mitochondrial proliferation, lipid secretion, and β-oxidation. The mechanism by which KLF controls these events in lipid metabolism is unknown. We have recently observed that C. elegans KLF-3 selectively acts on insulin components to regulate insulin pathway activity. There are many factors that control energy homeostasis and defects in this control system are implicated in the pathogenesis of human obesity and diabetes. In this review we are discussing a role of KLF in human metabolic regulation.