Biomarkers of heatstroke-induced organ injury and repair.

NEW FINDINGS: What is the topic of this review? The status and potential role of novel biological markers (biomarkers) that can help identify the patients at risk of organ injury or long-term complications following heatstroke. What advances does it highlight? Numerous biomarkers were identified related to many aspects of generalized heatstroke-induced cellular injury and tissue damage, and heatstroke-provoked cardiovascular, renal, cerebral, intestinal and skeletal muscle injury. No novel biomarkers were identified for liver or lung injury. ABSTRACT: Classic and exertional heatstroke cause acute injury and damage across numerous organ systems. Moreover, heatstroke survivors may sustain long-term neurological, cardiovascular and renal complications with a persistent risk of death. In this context, biomarkers, defined as biological samples obtained from heatstroke patients, are needed to detect early organ injury, and predict outcomes to develop novel organ preservation therapeutic strategies. This narrative review provides preliminary insights that will guide the development and future utilization of these biomarkers. To this end, we have identified numerous biomarkers of widespread heatstroke-associated cellular injury, tissue damage and repair (extracellular heat shock proteins 72 and 60, high mobility group box protein 1, histone H3, and interleukin-1α), and other organ-specific biomarkers including those related to the cardiovascular system (cardiac troponin I, endothelium-derived factors, circulation endothelial cells, adhesion molecules, thrombomodulin and von Willebrand factor antigen), the kidneys (plasma and urinary neutrophil gelatinase-associated lipocalin), the intestines (intestinal fatty acid-binding protein 2), the brain (serum S100ß and neuron-specific enolase) and skeletal muscle (creatine kinase, myoglobin). No specific biomarkers have been identified so far for liver or lung injury in heatstroke. Before translating the identified biomarkers into clinical practice, additional preclinical and clinical prospective studies are required to further understand their clinical utility, particularly for the biomarkers related to long-term post-heatstroke health outcomes.

Enhanced renoprotective actions of Paricalcitol and omega-3 fatty acids co-therapy against diabetic nephropathy in rat.

Introduction: Although the synthetic vitamin D analogue, Paricalcitol, and omega-3 Fatty acids (ω-3) alleviated diabetic nephropathy (DN), their combination was not previously explored. Objectives: This study measured the potential ameliorative effects of single and dual therapies of Paricalcitol and/or ω-3 against DN. Methods: Forty rats were assigned as follow: negative (NC) and positive (PC) controls, Paricalcitol, ω-3 and Paricalcitol + ω-3 groups. Diabetes was generated by high-fat/high-fructose diet and a single streptozotocin injection (40 mg/kg). DN was confirmed by raised fasting blood glucose (FBG), polyuria, proteinuria, and decreased urine creatinine levels. Paricalcitol intraperitoneal injections (0.25 µg/Kg/day; 5 times/week) and oral ω-3 (415 mg/kg/day; 5 times/week) started at week-9 and for eight weeks. Results: The PC group showed hyperglycaemia, dyslipidaemia, abnormal renal biochemical parameters, elevated caspase-3 expression, and increased apoptosis by TUNEL technique. The mRNAs and proteins of the pathogenic molecules (TGF-ß1/iNOS) and markers of tissue damage (NGAL/KIM-1) augmented substantially in the PC renal tissues relative to the NC group. The oxidative stress (MDA/H2O2/protein carbonyl groups) and pro-inflammatory (IL1ß/IL6/TNF-α) markers increased, whereas the anti-inflammatory (IL10) and anti-oxidative (GSH/GPx1/GR/SOD1/CAT) declined, in the PC renal tissues. The monotherapy groups were associated with ameliorated FBG, lipid profile and renal functions, and diminished TGF-ß1/iNOS/NGAL/KIM-1/Caspase-3 alongside the apoptotic index than the PC group. The oxidative stress and pro-inflammatory markers decreased, whilst the anti-oxidative and anti-inflammatory molecules escalated, in the monotherapy groups than the PC group. Although the Paricalcitol renoprotective actions were better than ω-3, all the biomarkers were abnormal than the NC group. Alternatively, the Paricalcitol + ω-3 protocol exhibited the best improvements in metabolic control, renal functions, oxidative stress, inflammation, and apoptosis. However, FBG and tissue damage were persistently higher in the co-therapy group than controls. Conclusions: Both monotherapies showed modest efficacy against DN, whereas their combination displayed boosted renoprotection, possibly by enhancing renal anti-oxidant and anti-inflammatory pathways.

Effects of combined administration of doxorubicin and chloroquine on lung pathology in mice with solid Ehrlich ascites carcinoma.

Combined use of a chemotherapeutic agent and an autophagy inhibitor is a novel cancer treatment strategy. We investigated the effects of chloroquine (CQ) on lung pathology caused by both solid Ehrlich ascites carcinoma (EAC) and doxorubicin (DXR). A control group and eight experimental groups of adult female mice were inoculated subcutaneously with 2.5 × 106 EAC cells. DXR (1.5 mg/kg and 3 mg/kg) and CQ (25 mg/kg and 50 mg/kg) alone or in combination were injected intraperitoneally on days 2, 7 and 12 following inoculation with EAC cells. Lung tissue samples were examined using immunohistochemistry (IHC) for endothelial (eNOS), inducible nitric oxide synthase (iNOS) and neutrophil gelatinase-associated lipocalin (NGAL). Serum catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD) and malondialdehyde (MDA) levels were measured using ELISA. We found decreased levels of iNOS and eNOS in the groups that received 1.5 mg/kg DXR alone and in combination with 25 mg/kg and 50 mg/kg CQ. Combined administration of DXR and CQ partially prevented disruption of alveolar structure. Levels of antioxidant enzymes and MDA were lower in all treated groups; the greatest reduction was observed in mice that received the combination of 25 mg/kg CQ + 1.5 mg/kg DXR. Levels of NGAL were elevated in all treated groups. We found that CQ ameliorated both EAC and DOX induced lung pathology in female mice with solid EAC by reducing oxidative stress.

Lipocalin 2 promotes inflammatory breast cancer tumorigenesis and skin invasion.

Inflammatory breast cancer (IBC) is an aggressive form of primary breast cancer characterized by rapid onset and high risk of metastasis and poor clinical outcomes. The biological basis for the aggressiveness of IBC is still not well understood and no IBC-specific targeted therapies exist. In this study, we report that lipocalin 2 (LCN2), a small secreted glycoprotein belonging to the lipocalin superfamily, is expressed at significantly higher levels in IBC vs non-IBC tumors, independently of molecular subtype. LCN2 levels were also significantly higher in IBC cell lines and in their culture media than in non-IBC cell lines. High expression was associated with poor-prognosis features and shorter overall survival in IBC patients. Depletion of LCN2 in IBC cell lines reduced colony formation, migration, and cancer stem cell populations in vitro and inhibited tumor growth, skin invasion, and brain metastasis in mouse models of IBC. Analysis of our proteomics data showed reduced expression of proteins involved in cell cycle and DNA repair in LCN2-silenced IBC cells. Our findings support that LCN2 promotes IBC tumor aggressiveness and offer a new potential therapeutic target for IBC.

Bone: Another potential target to treat, prevent and predict diabetes.

Type 2 diabetes mellitus is now a worldwide health problem with increasing prevalence. Mounting efforts have been made to treat, prevent and predict this chronic disease. In recent years, increasing evidence from mice and clinical studies suggests that bone-derived molecules modulate glucose metabolism. This review aims to summarize our current understanding of the interplay between bone and glucose metabolism and to highlight potential new means of therapeutic intervention. The first molecule recognized as a link between bone and glucose metabolism is osteocalcin (OCN), which functions in its active form, that is, undercarboxylated OCN (ucOC). ucOC acts in promoting insulin expression and secretion, facilitating insulin sensitivity, and favouring glucose and fatty acid uptake and utilization. A second bone-derived molecule, lipocalin2, functions in suppressing appetite in mice through its action on the hypothalamus. Osteocytes, the most abundant cells in bone matrix, are suggested to act on the browning of white adipose tissue and energy expenditure through secretion of bone morphogenetic protein 7 and sclerostin. The involvement of bone resorption in glucose homeostasis has also been examined. However, there is evidence indicating the implication of the receptor activator of nuclear factor κ-B ligand, neuropeptide Y, and other known and unidentified bone-derived factors that function in glucose homeostasis. We summarize recent advances and the rationale for treating, preventing and predicting diabetes by skeleton intervention.

Anticalins directed against vascular endothelial growth factor receptor 3 (VEGFR-3) with picomolar affinities show potential for medical therapy and in vivo imaging.

Members of the vascular endothelial growth factor receptor (VEGFR) family play a central role in angiogenesis as well as lymphangiogenesis and are crucial for tumor growth and metastasis. In particular, VEGFR-3 expression is induced in endothelial cells during tumor angiogenesis. We report the design of anticalins that specifically recognize the ligand-binding domains 1 and 2 of VEGFR-3. To this end, a library of the lipocalin 2 scaffold with 20 randomized positions distributed across its binding site was subjected to phage display selection and enzyme linked immunosorbent assay (ELISA) screening using the VEGF-C binding fragment (D1-2) or the entire extracellular region (D1-7) of VEGFR-3 as target proteins. Promising anticalin candidates were produced in Escherichia coli and biochemically characterized. Three variants with different receptor binding modes were identified, and two of them were optimized with regard to target affinity as well as folding efficiency. The resulting anticalins show dissociation constants down to the single-digit picomolar range. Specific recognition of VEGFR-3 on cells was demonstrated by immunofluorescence microscopy. Competitive binding versus VEGF-C was demonstrated for two of the anticalins with Ki values in the low nanomolar range. Based on these data, VEGFR-3 specific anticalins provide promising reagents for the diagnosis and/or therapeutic intervention of tumor-associated vessel growth.