HMGB1 Redox During Sepsis

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\u27s 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\u27s pro-inflammatory signaling. Conversely, the glutathione and thioredoxin systems work to maintain the protein in its reduced state

Low Birth Weight Is Associated with Impaired Murine Kidney Development And Function

BackgroundLow birth weight (LBW) neonates have impaired kidney development that leaves them susceptible to kidney disease and hypertension during adulthood. The study here identifies events that blunt nephrogenesis and kidney development in the murine LBW neonate.MethodsWe examined survival, kidney development, GFR, gene expression, and cyto-/chemokines in the LBW offspring of malnourished (caloric and protein-restricted) pregnant mice.ResultsMalnourished pregnant mothers gave birth to LBW neonates that had 40% reduced body weight and 54% decreased survival. Renal blood perfusion was reduced by 37%, whereas kidney volume and GFR were diminished in the LBW neonate. During gestation, the LBW neonatal kidney had 2.2-fold increased apoptosis, 76% decreased SIX2+. progenitor cells, downregulation of mesenchymal-to-epithelial signaling factors Wnt9b and Fgf8, 64% less renal vesicle formation, and 32% fewer nephrons than controls. At birth, increased plasma levels of IL-1beta, IL-6, IL-12(p70), and granulocyte-macrophage colony-stimulating factor in the LBW neonate reduced SIX2+. progenitor cells.ConclusionIncreased pro-inflammatory cytokines in the LBW neonate decrease SIX2+. stem cells in the developing kidney. Reduced renal stem cells (along with the decreased mesenchymal-to-epithelial signaling) blunt renal vesicle generation, nephron formation, and kidney development. Subsequently, the mouse LBW neonate has reduced glomeruli volume, renal perfusion, and GFR.Pediatric Research advance online publication, 31 May 2017; doi:10.1038/pr.2017.53

Kidney Dysfunction in the Low Birth Weight Murine Adult: Implications of Oxidative Stress

Maternal undernutrition during pregnancy leads to low birth weight (LBW) neonates that have a reduced kidney nephron endowment and higher morbidity as adults. Using a severe combined caloric and protein restricted mouse model of MUN to generate LBW mice, we examined the progression of renal insufficiency in LBW adults. Through 6 months of age, LBW males experienced greater albuminuria (ELISA analysis), a more rapid onset of glomerular hypertrophy and a worse survival rate than LBW females. In contrast, both genders experienced a comparable progressive decline in renal vascular density (immunofluorescence analysis), renal blood flow (Laser-Doppler flowmetry analysis), glomerular filtration rate (FITC-sinistrin clearance analysis), and a progressive increase in systemic blood pressure (measured via tail-cuff method). Isolated aortas from both LBW genders demonstrated reduced vasodilation in response to acetylcholine, indicative of reduced nitric oxide bioavailability and endothelial dysfunction. ELISA and immunofluorescence analysis revealed a significant increase of circulating reactive oxygen species and NADPH oxidase type 4 (NOX4) expression in both LBW genders, although these increases were more pronounced in males. Although more effective in males, chronic tempol treatment did improve all observed pathologies in both LBW genders. Chronic NOX4 inhibition with GKT137831 was more effective than tempol in preventing pathologies in LBW males. In conclusion, despite some minor differences, LBW female and male adults that have a reduced nephron endowment experience comparable progressive renal and vascular dysfunction that is associated with increased oxidative stress and subsequent endothelial dysfunction. Tempol treatment and/or NOX4 inhibition attenuates renal and vascular dysfunction in LBW adults

Maternal Malnourishment Induced Upregulation of Fetuin-B Blunts Nephrogenesis in the Low Birth Weight Neonate

Maternal undernutrition during pregnancy (MUN) often leads to low birth weight (LBW) neonates that have a reduced total nephron endowment, leaving these neonates susceptible to kidney disease throughout their lives. For reasons unknown, these LBW neonates have impaired kidney development due to a severe reduction in renal SIX2(+) stem cells during nephrogenesis. Using a mouse model of MUN, we investigated SIX2(+) stem cell reduction in the LBW neonate. Significant upregulation of the protein fetuin-B (measured by PCR and immunoblotting) in the MUN mother\u27s placenta, organs and circulation yielded a 3-fold increase of this protein in the embryonic kidney. Recombinant fetuin-B, administered to healthy pregnant mothers at the concentration equivalent to that in the MUN mother, crossed the placenta and reduced both SIX2(+) stem cells by 50% and nephron formation by 66% in embryonic kidneys (measured by immunofluorescence and the physical dissector/fractionator stereological method). Administration of fetuin-B to kidney explants yielded similar reductions in renal SIX2(+) stem cells and nephron formation. Fetuin-B treatment of isolated embryonic renal SIX2(+) stem cell primary cultures 1) increased NF-kB activity and apoptosis, 2) reduced cell proliferation due to upregulated p21 nuclear activity and subsequent cell cycle arrest, and 3) enhanced generation of reactive oxygen species (measured by fluorescence microscopy). In conclusion, MUN increases fetuin-B in the developing embryonic kidney. The increase in fetuin-B blunts nephrogenesis by reducing SIX2(+) stem cells by promoting their apoptosis (via NF-kB upregulation), blunting their proliferative renewal (via p21 upregulation) and enhancing oxidative stress

A population-based study of Kurdish breast cancer in northern Iraq: Hormone receptor and HER2 status. A comparison with Arabic women and United States SEER data

<p>Abstract</p> <p>Background</p> <p>Hormone receptor (HR) and HER2 expression predict the therapeutic response and prognosis of breast cancer. In the Middle-East, breast cancer is diagnosed at a young age, and Arabic women are reported to have a low frequency of HR positive tumors. This study investigates HR and HER2 expression among Kurdish and Arabic women.</p> <p>Methods</p> <p>During 2008–2010, the Sulaimaniyah Directorate of Health records identified 514 Sulaimaniyah Kurdish women, 227 Kurdish women of other Governates, and 83 Arabic women with a first diagnosis of breast cancer. The breast cancers of 432 women had immunohistochemistry (IHC) performed for estrogen and progesterone receptors (ER and PR) and HER2. Age specific and age standardized incidence rates were calculated for Sulaimaniyah Kurds. Results were compared with Egypt and with United States (US) SEER data.</p> <p>Results</p> <p>The median patient age was 46 years and 60.4% were < 50 years old. Tumors of 65.2% of women were ER+/HER2- with the rate increasing to 78.3% in patients ≥ 60 years old in proportions similar to US whites. The total annual age standardized incidence for breast cancer among Sulaimaniyah Kurds was 40.5/100,000 women, a rate similar to Egypt but much lower than the US. By HR/HER2 subtype, the highest age specific incidence rates were 16.4 and 45.4/100,000 for ER+/PR+/HER2- tumors in women < 50 or ≥ 50 years old, respectively (US whites: 37.7 and 226.1/100,000). Tumors of 20.4% of Sulaimaniyah women were HER2+ with annual incidence rates for ER-/PR-/HER2+ tumors of women <50 or ≥ 50 years old being 4.0 and 6.3/100,000 (US whites: 3.2 and 14.4/100,000). No significant differences in ER or HER2 status were found between Kurdish and Arabic patients.</p> <p>Conclusions</p> <p>Compared to the US, low age standardized and age specific breast cancer incidence rates were found in Kurdish women; nevertheless, the proportional expression of HR and HER2 for both Kurds and Arabs was comparable to that of US white women. The great majority of the breast cancer was ER+/HER2- and should respond to anti-estrogen therapy.</p