An injured skin is rapidly restored in a manner of wound healing. We have previously shown that intact insulin signaling and glucose uptake are fundamental to proper wound closure. Consequently, under exacerbated inflammation, compromised insulin action and glucose uptake lead to impaired healing.
View Article and Find Full Text PDFThe healing of wounded skin is a highly organized process involving a massive cell in- and outflux, proliferation and tissue remodelling. It is well accepted that metabolic constraints such as diabetes mellitus, overweight or anorexia impairs wound healing. Indeed, wound inflammation involves a boost of overall metabolic changes.
View Article and Find Full Text PDFMurine acetaminophen-induced acute liver injury (ALI) serves as paradigmatic model for drug-induced hepatic injury and regeneration. As major cause of ALI, acetaminophen overdosing is a persistent therapeutic challenge with N-acetylcysteine clinically used to ameliorate parenchymal necrosis. To identify further treatment strategies that serve patients with poor N-acetylcysteine responses, hepatic 3'mRNA sequencing was performed in the initial resolution phase at 24 h/48 h after sublethal overdosing.
View Article and Find Full Text PDFSystemic inflammation is associated with alterations in complex brain functions such as learning and memory. However, diagnostic approaches to functionally assess and quantify inflammation-associated alterations in synaptic plasticity are not well-established. In previous work, we demonstrated that bacterial lipopolysaccharide (LPS)-induced systemic inflammation alters the ability of hippocampal neurons to express synaptic plasticity, i.
View Article and Find Full Text PDFThe gaseous mediators nitric oxide (NO), carbon monoxide (CO) and lately also hydrogen sulfide (HS) have been described to contribute to the interplay of protein type- and lipid mediators in the regulation of wound healing. In particular, the recently reported role of HS in skin repair remains largely unresolved. Therefore we assessed the expressional kinetics of potential HS-producing enzymes during undisturbed skin repair: the cystathionine-γ-lyase (CSE), the cystathionine-β-synthase (CBS) and the 3-mercaptopyruvate sulfurtransferase (MPST).
View Article and Find Full Text PDFThe gaseous mediator nitric oxide (NO) is a central regulatory molecule during the inflammatory phase of cutaneous tissue repair. The inducible NO-synthase (iNOS) represents the main isoform of the three NO producing enzymes at the wound site. In particular, keratinocytes and macrophages are described as main sources of iNOS-derived NO in skin wounds.
View Article and Find Full Text PDFAm J Physiol Renal Physiol
June 2017
Deficiency of cyclooxygenase-2 (COX-2) activity in the early postnatal period causes impairment of kidney development leading to kidney insufficiency. We hypothesize that impaired NaCl reabsorption during the first days of life is a substantial cause for nephrogenic defects observed in COX-2 mice and that salt supplementation corrects these defects. Daily injections of NaCl (0.
View Article and Find Full Text PDFDeletion of cyclooxygenase-2 (COX-2) causes impairment of postnatal kidney development. Here we tested whether the renin angiotensin system contributes to COX-2-dependent nephrogenesis in mice after birth and whether a rescue of impaired renal development and function in COX-2 mice was achievable. Plasma renin concentration in mouse pups showed a birth peak and a second peak around day P8 during the first 10 days post birth.
View Article and Find Full Text PDFCombined diabetes-obesity syndromes severely impair regeneration of acute skin wounds in mouse models. This study assessed the contribution of subcutaneous adipose tissue to exacerbated wound inflammatory conditions. Genetically obese (ob/ob) mice showed an increased expression of positive transcriptional effectors of adipocyte differentiation such as Krüppel-like factor (KLF)-5 and peroxisome proliferator-activated receptor (PPAR)-γ and an associated expression of leptin and fatty acid-binding protein (FABP)-4, but also CXCL2 in isolated subcutaneous fat.
View Article and Find Full Text PDFInhibition of cyclooxygenase (Cox) enzymatic activity by non-steroidal anti-inflammatory drugs (NSAIDs) provides the molecular basis of analgesia following wounding or surgery. This study investigated the role of Cox activity in the regulation of vascular endothelial growth factor (VEGF) expression in keratinocytes and the formation of new blood vessels in acute wounds in mice. To this end, human HaCaT keratinocytes were stimulated with epidermal growth factor (EGF).
View Article and Find Full Text PDFThe determination of regenerative wound-healing macrophages as alternatively activated macrophages is currently questioned by the absence of IL-4 in wound tissue. Yet, murine wound tissue expressed high levels of Ym1 (chitinase 3-like 3), an established marker of the IL-4-induced alternatively activated macrophage phenotype. Ym1 was expressed in wound neutrophils but not in macrophages.
View Article and Find Full Text PDFType-2 diabetes mellitus (T2D) represents an important metabolic disorder, firmly connected to obesity and low level of chronic inflammation caused by deregulation of fat metabolism. The convergence of chronic inflammatory signals and nutrient overloading at the endoplasmic reticulum (ER) leads to activation of ER-specific stress responses, the unfolded protein response (UPR). As obesity and T2D are often associated with impaired wound healing, we investigated the role of UPR in the pathologic of diabetic-impaired cutaneuos wound healing.
View Article and Find Full Text PDFAcetaminophen (APAP, paracetamol)-induced hepatotoxicity, although treatable by timely application of N-acetylcysteine, can be fatal. Because it is among the common causes of acute liver failure in intensive care units and in light of its gradually increasing incidence, the need for novel therapeutic strategies aimed at severe intoxication is apparent. Recently, it has been shown that IL-22, a STAT3-activating cytokine, has the capability to mediate liver protection.
View Article and Find Full Text PDFIn the past, the genetically diabetic-obese diabetes/diabetes (db/db) and obese/obese (ob/ob) mouse strains were used to investigate mechanisms of diabetes-impaired wound healing. Here we determined patterns of skin repair in genetically normal C57Bl/6J mice that were fed using a high fat diet (HFD) to induce a diabetes-obesity syndrome. Wound closure was markedly delayed in HFD-fed mice compared to mice which had received a standard chow diet (CD).
View Article and Find Full Text PDFIf insufficiently treated, Lyme borreliosis can evolve into an inflammatory disorder affecting skin, joints, and the CNS. Early innate immunity may determine host responses targeting infection. Thus, we sought to characterize the immediate cytokine storm associated with exposure of PBMC to moderate levels of live Borrelia burgdorferi.
View Article and Find Full Text PDFAm J Respir Cell Mol Biol
March 2011
High-pressure ventilation induces barotrauma and pulmonary inflammation, thus leading to ventilator-induced lung injury (VILI). IL-22 has both immunoregulatory and tissue-protective properties. Functional IL-22 receptor expression is restricted to nonleukocytic cells, such as alveolar epithelial cells.
View Article and Find Full Text PDFRecently, the suppressor of cytokine signaling (SOCS)-3 has been shown to be expressed in disturbed wound margin epithelia during diabetes-impaired wound healing in mice. To functionally connect a potential contribution of SOCS-3 expression to the control of wound keratinocyte behavior in skin repair, we created a transgenic mouse (tsgn-K5/SOCS3) overexpressing SOCS-3 in keratinocytes using the bovine keratin 5 promoter. Tsgn-K5/SOCS3 mice showed a constitutive expression of SOCS-3 in the basal layer of skin epidermis.
View Article and Find Full Text PDFThe suppressor of cytokine signaling (SOCS)-3 has been shown to impair proliferation and migration of keratinocytes. To assess the functional dependency among wound inflammation, SOCS-3 induction in keratinocytes, and the outcome of healing, we generated a transgenic mouse that specifically overexpresses SOCS-3 in keratinocytes. Acute wound healing in transgenic mice was severely impaired.
View Article and Find Full Text PDFWhether the wound macrophage is a key regulatory inflammatory cell type in skin repair has been a matter of debate. A transgenic mouse model mediating inducible macrophage depletion during skin repair has not been used to date to address this question. Here, we specifically rendered the monocyte/macrophage leukocyte lineage sensitive to diphtheria toxin by expressing the lysozyme M promoter-driven, Cre-mediated excision of a transcriptional STOP cassette from the simian DT receptor gene in mice (lysM-Cre/DTR).
View Article and Find Full Text PDFObjective: We aimed to elucidate to date unknown molecular patterns of dynamic inflammatory tissue responses during uncomplicated healing of caudally pedicled skin flap transplants in mice.
Summary Background Data: Distal skin flap ischemic necrosis is a well-known complication in surgery. To improve ischemic conditions in impaired skin flaps, recent work attempted to increase insufficient vascularity by application of angiogenic growth factors or pluripotent cells.
Here we investigated the potential role of protein kinase B (Akt) in normal or diabetes-impaired wound healing in mice. Interestingly, Akt1 was predominant in skin, wound tissue, and human keratinocytes cell line. Acute skin repair was characterized by an increase of Akt1 phosphorylation in wound margin keratinocytes.
View Article and Find Full Text PDFThe peroxisome proliferator-activated receptors (PPARs) represent pharmacological target molecules to improve insulin resistance in type 2 diabetes mellitus. Here we assessed a functional connection between pharmacological activation of PPAR and vascular endothelial growth factor (VEGF) expression in keratinocytes and during diabetes-impaired acute skin repair in obese/obese (ob/ob) mice. PPARbeta/delta agonist 4-[3-[4-acetyl-3-hydroxy-2-propylphenoxy)propoxy]phenoxy]acetic acid (L165,041) and PPARgamma agonists ciglitazone and troglitazone, but not rosiglitazone, potently induced VEGF mRNA and protein expression from cultured keratinocytes.
View Article and Find Full Text PDFThe chemokine CXCL16 plays an important role in the recruitment of leukocytes to sites of inflammation influencing the course of experimental glomerulonephritis. Here we show that human kidneys highly express CXCL16 in the distal tubule, connecting tubule and principal cells of the collecting duct with weak expression in the thick ascending limb of Henle. Beside the membrane localization, a soluble form of CXCL16 can be proteolytically released which acts as a chemotactic factor.
View Article and Find Full Text PDFBiochem Biophys Res Commun
July 2008
Here, we determined the localization and activation of protein kinase B (Akt) in acute cutaneous wound tissue in mice. Akt1 represented the major Akt isoform that was expressed and activated in wound margin keratinocytes and also in the cultured human keratinocyte line HaCaT. Mutation of Akt1 protein, exchanging the activation-essential Ser473 and Thr308 residues for inactive Ala or phosphorylation-mimicking Asp and Glu residues, revealed that phosphorylation of Ser473 represented an essential prerequisite for auto-phosphorylation of Thr308 within the Akt1 protein in keratinocytes.
View Article and Find Full Text PDFIn this study, we determined the regulation and potential function of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase (HMGR) during skin repair in mice. Upon skin injury, healthy mice exhibited a biphasic increase in HMGR expression and activity with elevated levels at days 3 and 13 post-wounding. In situ hybridization revealed wound margin keratinocytes as a cellular source of HMGR expression.
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