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1.
Kidney Int ; 105(1): 65-83, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37774921

ABSTRACT

Glomerular-tubular crosstalk within the kidney has been proposed, but the paracrine signals enabling this remain largely unknown. The cold-shock protein Y-box binding protein 1 (YBX1) is known to regulate inflammation and kidney diseases but its role in podocytes remains undetermined. Therefore, we analyzed mice with podocyte specific Ybx1 deletion (Ybx1ΔPod). Albuminuria was increased in unchallenged Ybx1ΔPod mice, which surprisingly was associated with reduced glomerular, but enhanced tubular damage. Tubular toll-like receptor 4 (TLR4) expression, node-like receptor protein 3 (NLRP3) inflammasome activation and kidney inflammatory cell infiltrates were all increased in Ybx1ΔPod mice. In vitro, extracellular YBX1 inhibited NLRP3 inflammasome activation in tubular cells. Co-immunoprecipitation, immunohistochemical analyses, microscale cell-free thermophoresis assays, and blunting of the YBX1-mediated TLR4-inhibition by a unique YBX1-derived decapeptide suggests a direct interaction of YBX1 and TLR4. Since YBX1 can be secreted upon post-translational acetylation, we hypothesized that YBX1 secreted from podocytes can inhibit TLR4 signaling in tubular cells. Indeed, mice expressing a non-secreted YBX1 variant specifically in podocytes (Ybx1PodK2A mice) phenocopied Ybx1ΔPod mice, demonstrating a tubular-protective effect of YBX1 secreted from podocytes. Lipopolysaccharide-induced tubular injury was aggravated in Ybx1ΔPod and Ybx1PodK2A mice, indicating a pathophysiological relevance of this glomerular-tubular crosstalk. Thus, our data show that YBX1 is physiologically secreted from podocytes, thereby negatively modulating sterile inflammation in the tubular compartment, apparently by binding to and inhibiting tubular TLR4 signaling. Hence, we have uncovered an YBX1-dependent molecular mechanism of glomerular-tubular crosstalk.


Subject(s)
Kidney Diseases , Podocytes , Mice , Animals , Inflammasomes/metabolism , Toll-Like Receptor 4/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Cold-Shock Response , Kidney/metabolism , Podocytes/metabolism , Kidney Diseases/metabolism , Inflammation/metabolism
2.
Tissue Eng Regen Med ; 21(1): 137-157, 2024 01.
Article in English | MEDLINE | ID: mdl-37847444

ABSTRACT

BACKGROUND: Thermal traumas impose a huge burden on healthcare systems. This merits the need for advanced but cost-effective remedies with clinical prospects. In this context, we prepared a regenerative 3D-construct comprising of Cassia angustifolia extract (SM) primed adipose-derived stem cells (ASCs) laden amniotic membrane for faster burn wound repair. METHODS: ASCs were preconditioned with SM (30 µg/ml for 24 h), and subsequently exposed to in-vitro thermal injury (51 °C,10 min). In-vivo thermal injury was induced by placing pre-heated copper-disc (2 cm diameter) on dorsum of the Wistar rats. ASCs (2.0 × 105) pre-treated with SM (SM-ASCs), cultured on stromal side of amniotic membrane (AM) were transplanted in rat heat-injury model. Non-transplanted heat-injured rats and non-heat-injured rats were kept as controls. RESULTS: The significantly upregulated expression of IGF1, SDF1A, TGFß1, VEGF, GSS, GSR, IL4, BCL2 genes and downregulation of BAX, IL6, TNFα, and NFkB1 in SM-ASCs in in-vitro and in-vivo settings confirmed its potential in promoting cell-proliferation, migration, angiogenesis, antioxidant, cell-survival, anti-inflammatory, and wound healing activity. Moreover, SM-ASCs induced early wound closure, better architecture, normal epidermal thickness, orderly-arranged collagen fibers, and well-developed skin appendages in healed rat-skin transplanted with AM+SM-ASCs, additionally confirmed by increased expression of structural genes (Krt1, Krt8, Krt19, Desmin, Vimentin, α-Sma) in comparison to untreated-ASCs laden-AM transplanted in heat injured rats. CONCLUSION: SM priming effectively enabled ASCs to counter thermal injury by significantly enhancing cell survival and reducing inflammation upon transplantation. This study provides bases for development of effective combinational therapies (natural scaffold, medicine, and stem cells) with clinical prospects for treating burn wounds.


Subject(s)
Burns , Senna Plant , Rats , Animals , Rats, Wistar , Wound Healing , Skin/injuries , Burns/therapy
3.
Immunity ; 57(1): 68-85.e11, 2024 Jan 09.
Article in English | MEDLINE | ID: mdl-38141610

ABSTRACT

Tissue factor (TF), which is a member of the cytokine receptor family, promotes coagulation and coagulation-dependent inflammation. TF also exerts protective effects through unknown mechanisms. Here, we showed that TF bound to interferon-α receptor 1 (IFNAR1) and antagonized its signaling, preventing spontaneous sterile inflammation and maintaining immune homeostasis. Structural modeling and direct binding studies revealed binding of the TF C-terminal fibronectin III domain to IFNAR1, which restricted the expression of interferon-stimulated genes (ISGs). Podocyte-specific loss of TF in mice (PodΔF3) resulted in sterile renal inflammation, characterized by JAK/STAT signaling, proinflammatory cytokine expression, disrupted immune homeostasis, and glomerulopathy. Inhibiting IFNAR1 signaling or loss of Ifnar1 expression in podocytes attenuated these effects in PodΔF3 mice. As a heteromer, TF and IFNAR1 were both inactive, while dissociation of the TF-IFNAR1 heteromer promoted TF activity and IFNAR1 signaling. These data suggest that the TF-IFNAR1 heteromer is a molecular switch that controls thrombo-inflammation.


Subject(s)
Signal Transduction , Thromboplastin , Animals , Mice , Inflammation , Interferon-alpha , Receptor, Interferon alpha-beta/genetics , Receptor, Interferon alpha-beta/metabolism , Thromboplastin/genetics
4.
BMC Plant Biol ; 23(1): 629, 2023 Dec 08.
Article in English | MEDLINE | ID: mdl-38062351

ABSTRACT

Chromium (Cr) toxicity significantly threatens sunflower growth and productivity by interfering with enzymatic activity and generating reactive oxygen species (ROS). Zinc quantum dot biochar (ZQDB) and arbuscular mycorrhizal fungi (AMF) have become popular to resolve this issue. AMF can facilitate root growth, while biochar tends to minimize Cr mobility in soil. The current study aimed to explore AMF and ZQDB combined effects on sunflower plants in response to Cr toxicity. Four treatments were applied, i.e. NoAMF + NoZQDB, AMF + 0.40%ZQDB, AMF + 0.80%ZQDB, and AMF + 1.20%ZQDB, under different stress levels of Cr, i.e. no Cr (control), 150 and 200 mg Cr/kg soil. Results showed that AMF + 1.20%ZQDB was the treatment that caused the greatest improvement in plant height, stem diameter, head diameter, number of leaves per plant, achenes per head, 1000 achenes weight, achene yield, biological yield, transpiration rate, stomatal conductance, chlorophyll content and oleic acid, relative to the condition NoAMF + No ZQDB at 200 mg Cr/kg soil. A significant decline in peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) while improvement in ascorbate peroxidase (APx), oil content, and protein content further supported the effectiveness of AMF + 1.20%ZQDB against Cr toxicity. Our results suggest that the treatment AMF + 1.20%ZQDB can efficiently alleviate Cr stress in sunflowers.


Subject(s)
Helianthus , Mycorrhizae , Quantum Dots , Mycorrhizae/physiology , Antioxidants/metabolism , Helianthus/metabolism , Chromium/toxicity , Chromium/metabolism , Soil , Plant Roots/metabolism
5.
Front Immunol ; 14: 1252384, 2023.
Article in English | MEDLINE | ID: mdl-37701434

ABSTRACT

Introduction: The interleukin-1 (IL-1) family and the NLR family pyrin domain-containing 3 (NLRP3) inflammasome contribute to atherogenesis but the underlying mechanisms are incompletely understood. Unlike IL-1ß, IL-1α is not dependent on the NLRP3 inflammasome to exert its pro-inflammatory effects. Here, a non-genetic model was applied to characterize the role of IL-1α, IL-1ß, and NLRP3 for the pathogenesis of atherosclerosis. Methods: Atherogenesis was induced by gain-of-function PCSK9-AAV8 mutant viruses and feeding of a high-fat western diet (WTD) for 12 weeks in C57Bl6/J wildtype mice (WT) and in Il1a-/-, Nlrp3-/-, and Il1b-/- mice. Results: PCSK9-Il1a-/- mice showed reduced atherosclerotic plaque area in the aortic root with lower lipid accumulation, while no difference was observed between PCSK9-WT, PCSK9-Nlrp3-/- and PCSK9-Il1b-/- mice. Serum proteomic analysis showed a reduction of pro-inflammatory cytokines (e.g., IL-1ß, IL-6) in PCSK9-Il1a-/- as well as in PCSK9-Nlrp3-/- and PCSK9-Il1b-/- mice. Bone marrow dendritic cells (BMDC) of PCSK9-WT, PCSK9-Nlrp3-/-, and PCSK9-Il1b-/- mice and primary human monocytes showed translocation of IL-1α to the plasma membrane (csIL-1α) upon stimulation with LPS. The translocation of IL-1α to the cell surface was regulated by myristoylation and increased in mice with hypercholesterolemia. CsIL-1α and IL1R1 protein-protein interaction on endothelial cells induced VCAM1 expression and monocyte adhesion, which was abrogated by the administration of neutralizing antibodies against IL-1α and IL1R1. Conclusion: The results highlight the importance of IL-1α on the cell surface of circulating leucocytes for the development of atherosclerosis. PCSK9-Il1a-/- mice, but not PCSK9-Nlrp3-/- or PCSK9-Il1b-/- mice, are protected from atherosclerosis after induction of hypercholesterolemia independent of circulating cytokines. Myristoylation and translocation of IL-1α to the cell surface in myeloid cells facilitates leukocyte adhesion and contributes to the development of atherosclerosis.


Subject(s)
Atherosclerosis , Hypercholesterolemia , Animals , Humans , Mice , Atherosclerosis/genetics , Endothelial Cells , Inflammasomes , Interleukin-1alpha , Leukocytes , NLR Family, Pyrin Domain-Containing 3 Protein , Proteomics
7.
Blood Adv ; 7(17): 5055-5068, 2023 09 12.
Article in English | MEDLINE | ID: mdl-37315174

ABSTRACT

A direct regulation of adaptive immunity by the coagulation protease activated protein C (aPC) has recently been established. Preincubation of T cells with aPC for 1 hour before transplantation increases FOXP3+ regulatory T cells (Tregs) and reduces acute graft-versus-host disease (aGVHD) in mice, but the underlying mechanism remains unknown. Because cellular metabolism modulates epigenetic gene regulation and plasticity in T cells, we hypothesized that aPC promotes FOXP3+ expression by altering T-cell metabolism. To this end, T-cell differentiation was assessed in vitro using mixed lymphocyte reaction or plate-bound α-CD3/CD28 stimulation, and ex vivo using T cells isolated from mice with aGVHD without and with aPC preincubation, or analyses of mice with high plasma aPC levels. In stimulated CD4+CD25- cells, aPC induces FOXP3 expression while reducing expression of T helper type 1 cell markers. Increased FOXP3 expression is associated with altered epigenetic markers (reduced 5-methylcytosine and H3K27me3) and reduced Foxp3 promoter methylation and activity. These changes are linked to metabolic quiescence, decreased glucose and glutamine uptake, decreased mitochondrial metabolism (reduced tricarboxylic acid metabolites and mitochondrial membrane potential), and decreased intracellular glutamine and α-ketoglutarate levels. In mice with high aPC plasma levels, T-cell subpopulations in the thymus are not altered, reflecting normal T-cell development, whereas FOXP3 expression in splenic T cells is reduced. Glutamine and α-ketoglutarate substitution reverse aPC-mediated FOXP3+ induction and abolish aPC-mediated suppression of allogeneic T-cell stimulation. These findings show that aPC modulates cellular metabolism in T cells, reducing glutamine and α-ketoglutarate levels, which results in altered epigenetic markers, Foxp3 promoter demethylation and induction of FOXP3 expression, thus favoring a Treg-like phenotype.


Subject(s)
Ketoglutaric Acids , Protein C , Mice , Animals , Ketoglutaric Acids/metabolism , Protein C/metabolism , Glutamine/genetics , Glutamine/metabolism , T-Lymphocytes, Regulatory , Epigenesis, Genetic , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism
8.
Kidney Int ; 103(2): 304-319, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36309126

ABSTRACT

Dysfunction of mesangial cells plays a major role in the pathogenesis of diabetic kidney disease (DKD), the leading cause of kidney failure. However, the underlying molecular mechanisms are incompletely understood. By unbiased gene expression analysis of glucose-exposed mesangial cells, we identified the transmembrane receptor CD248 as the most upregulated gene, and the maladaptive unfolded protein response (UPR) as one of the most stimulated pathways. Upregulation of CD248 was further confirmed in glucose-stressed mesangial cells in vitro, in kidney glomeruli isolated from diabetic mice (streptozotocin; STZ and db/db models, representing type 1 and type 2 diabetes mellitus, respectively) in vivo, and in glomerular kidney sections from patients with DKD. Time course analysis revealed that glomerular CD248 induction precedes the onset of albuminuria, mesangial matrix expansion and maladaptive UPR activation (hallmarked by transcription factor C/EBP homologous protein (CHOP) induction) but is paralleled by loss of the adaptive UPR regulator spliced X box binding protein (XBP1). Mechanistically, CD248 promoted maladaptive UPR signaling via inhibition of the inositol requiring enzyme 1α (IRE1α)-mediated transcription factor XBP1 splicing in vivo and in vitro. CD248 induced a multiprotein complex comprising heat shock protein 90, BH3 interacting domain death agonist (BID) and IRE1α, in which BID impedes IRE1α-mediated XBP1 splicing and induced CHOP mediated maladaptive UPR signaling. While CD248 knockout ameliorated DKD-associated glomerular dysfunction and reverses maladaptive unfolded protein response signaling, concomitant XBP1 deficiency abolished the protective effect in diabetic CD248 knockout mice, supporting a functional interaction of CD248 and XBP1 in vivo. Hence, CD248 is a novel mesangial cell receptor inducing maladaptive UPR signaling in DKD.


Subject(s)
Diabetes Mellitus, Experimental , Diabetes Mellitus, Type 2 , Diabetic Nephropathies , Animals , Mice , Antigens, CD/metabolism , Antigens, Neoplasm , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/genetics , Diabetic Nephropathies/genetics , Endoribonucleases/genetics , Endoribonucleases/metabolism , Protein Serine-Threonine Kinases/genetics , Transcription Factors/metabolism , Unfolded Protein Response , Humans
9.
Braz. J. Pharm. Sci. (Online) ; 59: e20493, 2023. tab, graf
Article in English | LILACS | ID: biblio-1439545

ABSTRACT

Abstract Hedera nepalensis (H. nepalensis) , belonging to the family Araliaceae, is a medicinal plant traditionally used to treat stomach problems. The current study investigated the gastroprotective potential and the mechanism of action of H. nepalensis in diclofenac-and ethanol-induced ulcer models. Anti-oxidant and lipid peroxidation inhibitory prospects of H. nepalensis were checked out by free radical scavenging assay and UV spectrophotometer respectively. Effect of H. nepalensis on the pH, gastric total acidity of gastric juice and protective effects of H. nepalensis against ulcer models have been examined. Histopathological studies have been carried out. The aqueous methanol extract of H. nepalensis (100 µg/mL) showed anti-oxidant (83.55%) and lipid peroxidation inhibitory (70.88%) potential at 1000 µg/mL; the extract had no buffer potential. The extract (400 mg/kg) significantly (81.12% and 63.46%) showed gastroprotective effect in diclofenac and ethanol-induced rat ulcer models respectively. Histopathological studies confirmed the biochemical findings. FTIR analysis showed the presence of carboxylic acid, alkanes, conjugated alkanes, aldehydes and alkyl-aryl ethers. Gallic acid, M-coumaric acid and quercetin were found by HPLC analysis. H. nepalensis exhibited significant protection against diclofenac and ethanol induced gastric damage by anti-oxidant and lipid peroxidation suppression effects suggesting potential broad utility in treatment of diseases characterized with gastric damage.


Subject(s)
Plants, Medicinal , Stomach/abnormalities , Stomach Ulcer/pathology , Araliaceae/classification , Hedera/classification , Ulcer/chemically induced , Diclofenac/agonists , Chromatography, High Pressure Liquid/methods , Spectroscopy, Fourier Transform Infrared/methods , Antioxidants
10.
Genes (Basel) ; 13(9)2022 08 29.
Article in English | MEDLINE | ID: mdl-36140722

ABSTRACT

Cardiac dysfunction accelerates the risk of heart failure, and its pathogenesis involves a complex interaction between genetic and environmental factors. Variations in myosin affect contractile abilities of cardiomyocytes and cause structural and functional abnormalities in myocardium. The study aims to find the association of MYH7 rs121913642 (c.1594 T>C) and rs121913645 (c.667G>A) variants with cardiac dysfunction in the Punjabi Pakistani population. Patients with heart failure (n = 232) and healthy controls (n = 205) were enrolled in this study. MYH7 variant genotyping was performed using tetra ARMS-PCR. MYH7 rs121913642 TC genotype was significantly more prevalent in the patient group (p < 0.001). However, MYH7 rs121913645 genotype frequencies were not significantly different between the patient and control groups (p < 0.666). Regression analysis also revealed that the rs121913642 C allele increases the risk of cardiac failure by ~2 [OR:1.98, CI: 1.31−2.98, p < 0.001] in comparison to the T allele. High levels of the cardiac enzymes cardiac troponin I (cTnI) and CK-MB were observed in patients. There was also an increase in total cholesterol, LDL cholesterol, and uric acid in patients compared to the healthy control group (p < 0.001). In conclusion, the MYH7 gene variant rs121913642 is genetically associated with cardiac dysfunction and involved in the pathogenesis of HF.


Subject(s)
Heart Diseases , Heart Failure , Myosin Heavy Chains/genetics , Cardiac Myosins/genetics , Cholesterol, LDL/genetics , Heart Failure/genetics , Humans , Mutation , Phenotype , Troponin I/genetics , Uric Acid , Ventricular Myosins/genetics
11.
Nat Commun ; 13(1): 5062, 2022 08 27.
Article in English | MEDLINE | ID: mdl-36030260

ABSTRACT

A major obstacle in diabetes is the metabolic or hyperglycemic memory, which lacks specific therapies. Here we show that glucose-mediated changes in gene expression largely persist in diabetic kidney disease (DKD) despite reversing hyperglycemia. The senescence-associated cyclin-dependent kinase inhibitor p21 (Cdkn1a) was the top hit among genes persistently induced by hyperglycemia and was associated with induction of the p53-p21 pathway. Persistent p21 induction was confirmed in various animal models, human samples and in vitro models. Tubular and urinary p21-levels were associated with DKD severity and remained elevated despite improved blood glucose levels in humans. Mechanistically, sustained tubular p21 expression in DKD is linked to demethylation of its promoter and reduced DNMT1 expression. Two disease resolving agents, protease activated protein C (3K3A-aPC) and parmodulin-2, reversed sustained tubular p21 expression, tubular senescence, and DKD. Thus, p21-dependent tubular senescence is a pathway contributing to the hyperglycemic memory, which can be therapeutically targeted.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p21 , Diabetes Mellitus , Diabetic Nephropathies , Hyperglycemia , Animals , Cellular Senescence , Cyclin-Dependent Kinase Inhibitor p21/genetics , Diabetes Mellitus/pathology , Diabetic Nephropathies/pathology , Humans , Hyperglycemia/pathology , Kidney
12.
Nutrients ; 14(15)2022 Jul 29.
Article in English | MEDLINE | ID: mdl-35956315

ABSTRACT

Diabetic kidney disease (DKD) is an emerging pandemic, paralleling the worldwide increase in obesity and diabetes mellitus. DKD is now the most frequent cause of end-stage renal disease and is associated with an excessive risk of cardiovascular morbidity and mortality. DKD is a consequence of systemic endothelial dysfunction. The endothelial-dependent cytoprotective coagulation protease activated protein C (aPC) ameliorates glomerular damage in DKD, in part by reducing mitochondrial ROS generation in glomerular cells. Whether aPC reduces mitochondrial ROS generation in the tubular compartment remains unknown. Here, we conducted expression profiling of kidneys in diabetic mice (wild-type and mice with increased plasma levels of aPC, APChigh mice). The top induced pathways were related to metabolism and in particular to oxidoreductase activity. In tubular cells, aPC maintained the expression of genes related to the electron transport chain, PGC1-α expression, and mitochondrial mass. These effects were associated with reduced mitochondrial ROS generation. Likewise, NLRP3 inflammasome activation and sterile inflammation, which are known to be linked to excess ROS generation in DKD, were reduced in diabetic APChigh mice. Thus, aPC reduces mitochondrial ROS generation in tubular cells and dampens the associated renal sterile inflammation. These studies support approaches harnessing the cytoprotective effects of aPC in DKD.


Subject(s)
Diabetes Mellitus, Experimental , Diabetic Nephropathies , Animals , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/metabolism , Diabetic Nephropathies/etiology , Inflammation/complications , Kidney/metabolism , Mice , Protein C , Reactive Oxygen Species/metabolism
13.
Nutrients ; 14(14)2022 Jul 06.
Article in English | MEDLINE | ID: mdl-35889743

ABSTRACT

Diabetes mellitus is hallmarked by accelerated atherosclerosis, a major cause of mortality among patients with diabetes. Efficient therapies for diabetes-associated atherosclerosis are absent. Accelerated atherosclerosis in diabetic patients is associated with reduced endothelial thrombomodulin (TM) expression and impaired activated protein C (aPC) generation. Here, we directly compared the effects of high glucose and oxidized LDL, revealing that high glucose induced more pronounced responses in regard to maladaptive unfolded protein response (UPR), senescence, and vascular endothelial cell barrier disruption. Ex vivo, diabetic ApoE-/- mice displayed increased levels of senescence and UPR markers within atherosclerotic lesions compared with nondiabetic ApoE-/- mice. Activated protein C pretreatment maintained barrier permeability and prevented glucose-induced expression of senescence and UPR markers in vitro. These data suggest that high glucose-induced maladaptive UPR and associated senescence promote vascular endothelial cell dysfunction, which-however-can be reversed by aPC. Taken together, current data suggest that reversal of glucose-induced vascular endothelial cell dysfunction is feasible.


Subject(s)
Atherosclerosis , Diabetes Mellitus , Endoplasmic Reticulum Stress , Animals , Atherosclerosis/etiology , Atherosclerosis/physiopathology , Cellular Senescence , Glucose/pharmacology , Mice , Mice, Inbred C57BL , Mice, Knockout, ApoE , Protein C
14.
Nutrients ; 14(14)2022 Jul 20.
Article in English | MEDLINE | ID: mdl-35889923

ABSTRACT

Diabetes mellitus is a metabolic disease largely due to lifestyle and nutritional imbalance, resulting in insulin resistance, hyperglycemia and vascular complications. Diabetic kidney disease (DKD) is a major cause of end-stage renal failure contributing to morbidity and mortality worldwide. Therapeutic options to prevent or reverse DKD progression are limited. Endothelial and glomerular filtration barrier (GFB) dysfunction and sterile inflammation are associated with DKD. Neutrophil extracellular traps (NETs), originally identified as an innate immune mechanism to combat infection, have been implicated in sterile inflammatory responses in non-communicable diseases. However, the contribution of NETs in DKD remains unknown. Here, we show that biomarkers of NETs are increased in diabetic mice and diabetic patients and that these changes correlate with DKD severity. Mechanistically, NETs promote NLRP3 inflammasome activation and glomerular endothelial dysfunction under high glucose stress in vitro and in vivo. Inhibition of NETs (PAD4 inhibitor) ameliorate endothelial dysfunction and renal injury in DKD. Taken together, NET-induced sterile inflammation promotes diabetes-associated endothelial dysfunction, identifying a new pathomechanism contributing to DKD. Inhibition of NETs may be a promising therapeutic strategy in DKD.


Subject(s)
Diabetes Mellitus, Experimental , Diabetic Nephropathies , Extracellular Traps , Animals , Diabetes Mellitus, Experimental/complications , Diabetic Nephropathies/drug therapy , Extracellular Traps/metabolism , Inflammasomes/metabolism , Inflammation/complications , Mice , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism
15.
Kidney Int ; 102(4): 766-779, 2022 10.
Article in English | MEDLINE | ID: mdl-35779608

ABSTRACT

Efficient therapies for diabetic kidney disease (DKD), now the leading cause of kidney failure, are lacking. One hallmark of DKD is sterile inflammation (inflammation in absence of microorganisms), but the underlying molecular mechanisms remain poorly understood. The NLRP3 inflammasome (innate immune system receptors and sensors regulating activation of caspase-1) is a mechanism of sterile inflammation known to be activated by metabolic stimuli and reactive metabolites associated with DKD, including inflammasome activation in podocytes. However, whether NLRP3 inflammasome activation in podocytes contributes to sterile inflammation and glomerular damage in DKD remains unknown. Here, we found that kidney damage, as reflected by increased albuminuria, glomerular mesangial expansion and glomerular basement membrane thickness was aggravated in hyperglycemic mice with podocyte-specific expression of an Nlrp3 gain-of-function mutant (Nlrp3A350V). In contrast, hyperglycemic mice with podocyte-specific Nlrp3 or Caspase-1 deficiency showed protection against DKD. Intriguingly, podocyte-specific Nlrp3 deficiency was fully protective, while podocyte-specific caspase-1 deficiency was only partially protective. Podocyte-specific Nlrp3, but not caspase-1 deficiency, maintained glomerular autophagy in hyperglycemic mice, suggesting that podocyte Nlrp3 exerts both canonical and non-canonical effects. Thus, podocyte NLRP3 inflammasome activation is both sufficient and required for DKD and supports the concept that podocytes exert some immune cell-like functions. Hence, as podocyte NLRP3 exerts non-canonical and canonical effects, targeting NLRP3 may be a promising therapeutic approach in DKD.


Subject(s)
Diabetes Mellitus , Diabetic Nephropathies , Podocytes , Animals , Diabetes Mellitus/metabolism , Diabetic Nephropathies/genetics , Diabetic Nephropathies/metabolism , Inflammasomes/metabolism , Inflammation/metabolism , Mice , Mice, Obese , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Podocytes/metabolism
16.
Nutrients ; 14(10)2022 May 10.
Article in English | MEDLINE | ID: mdl-35631132

ABSTRACT

Diabetes mellitus, which is largely driven by nutritional and behavioral factors, is characterized by accelerated atherosclerosis with impaired plaque stability. Atherosclerosis and associated complications are the major cause of mortality in diabetic patients. Efficient therapeutic concepts for diabetes-associated atherosclerosis are lacking. Atherosclerosis among diabetic patients is associated with reduced endothelial thrombomodulin (TM) expression and impaired activated protein C (aPC) generation. Here, we demonstrate that atherosclerotic plaque stability is reduced in hyperglycemic mice expressing dysfunctional TM (TMPro/Pro mice), which have a pro-coagulant phenotype due to impaired thrombin inhibition and markedly reduced aPC generation. The vessel lumen and plaque size of atherosclerotic lesions in the truncus brachiocephalic were decreased in diabetic TMPro/Pro ApoE-/- mice compared to diabetic ApoE-/- mice. While lipid accumulation in lesions of diabetic TMPro/Pro ApoE-/- mice was lower than that in diabetic ApoE-/- mice, morphometric analyses revealed more prominent signs of instable plaques, such as a larger necrotic core area and decreased fibrous cap thickness in diabetic TMPro/Pro ApoE-/- mice. Congruently, more macrophages and fewer smooth muscle cells were observed within lesions of diabetic TMPro/Pro ApoE-/- mice. Thus, impaired TM function reduces plaque stability, a characteristic of hyperglycemia-associated plaques, thus suggesting the crucial role of impaired TM function in mediating diabetes-associated atherosclerosis.


Subject(s)
Atherosclerosis , Diabetes Mellitus , Plaque, Atherosclerotic , Thrombophilia , Animals , Atherosclerosis/metabolism , Diabetes Mellitus/pathology , Humans , Mice , Mice, Knockout, ApoE , Myocytes, Smooth Muscle/metabolism , Plaque, Atherosclerotic/complications
17.
Front Cardiovasc Med ; 9: 866751, 2022.
Article in English | MEDLINE | ID: mdl-35433860

ABSTRACT

Hemostasis, thrombosis, and inflammation are tightly interconnected processes which may give rise to thrombo-inflammation, involved in infectious and non-infectious acute and chronic diseases, including cardiovascular diseases (CVD). Traditionally, due to its hemostatic role, blood coagulation is isolated from the inflammation, and its critical contribution in the progressing CVD is underrated, until the full occlusion of a critical vessel occurs. Underlying vascular injury exposes extracellular matrix to deposit platelets and inflammatory cells. Platelets being key effector cells, bridge all the three key processes (hemostasis, thrombosis, and inflammation) associated with thrombo-inflammation. Under physiological conditions, platelets remain in an inert state despite the proximity to the endothelium and other cells which are decorated with glycosaminoglycan (GAG)-rich glycocalyx (GAGs). A pathological insult to the endothelium results in an imbalanced blood coagulation system hallmarked by increased thrombin generation due to losses of anticoagulant and cytoprotective mechanisms, i.e., the endothelial GAGs enhancing antithrombin, tissue factor pathway-inhibitor (TFPI) and thrombomodulin-protein C system. Moreover, the loss of GAGs promotes the release of mediators, such as von Willebrand factor (VWF), platelet factor 4 (PF4), and P-selectin, both locally on vascular surfaces and to circulation, further enhancing the adhesion of platelets to the affected sites. Platelet-neutrophil interaction and formation of neutrophil extracellular traps foster thrombo-inflammatory mechanisms exacerbating the cardiovascular disease course. Therefore, therapies which not only target the clotting mechanisms but simultaneously or independently convey potent cytoprotective effects hemming the inflammatory mechanisms are expected to provide clinical benefits. In this regard, we review the cytoprotective protease activated protein C (aPC) and its strong anti-inflammatory effects thereby preventing the ensuing thrombotic complications in CVD. Furthermore, restoring GAG-like vasculo-protection, such as providing heparin-proteoglycan mimetics to improve regulation of platelet and coagulation activity and to suppress of endothelial perturbance and leukocyte-derived pro-inflammatory cytokines, may provide a path to alleviate thrombo-inflammatory disorders in the future. The vascular tissue-modeled heparin proteoglycan mimic, antiplatelet and anticoagulant compound (APAC), dual antiplatelet and anticoagulant, is an injury-targeting and locally acting arterial antithrombotic which downplays collagen- and thrombin-induced and complement-induced activation and protects from organ injury.

18.
Front Cardiovasc Med ; 9: 813215, 2022.
Article in English | MEDLINE | ID: mdl-35350534

ABSTRACT

Objective: Atherosclerosis, the main pathology underlying cardiovascular diseases is accelerated in diabetic patients. Genetic mouse models require breeding efforts which are time-consuming and costly. Our aim was to establish a new nongenetic model of inducible metabolic risk factors that mimics hyperlipidemia, hyperglycemia, or both and allows the detection of phenotypic differences dependent on the metabolic stressor(s). Methods and Results: Wild-type mice were injected with gain-of-function PCSK9D377Y (proprotein convertase subtilisin/kexin type 9) mutant adeno-associated viral particles (AAV) and streptozotocin and fed either a high-fat diet (HFD) for 12 or 20 weeks or a high-cholesterol/high-fat diet (Paigen diet, PD) for 8 weeks. To evaluate atherosclerosis, two different vascular sites (aortic sinus and the truncus of the brachiocephalic artery) were examined in the mice. Combined hyperlipidemic and hyperglycemic (HGHCi) mice fed a HFD or PD displayed characteristic features of aggravated atherosclerosis when compared to hyperlipidemia (HCi HFD or PD) mice alone. Atherosclerotic plaques of HGHCi HFD animals were larger, showed a less stable phenotype (measured by the increased necrotic core area, reduced fibrous cap thickness, and less α-SMA-positive area) and had more inflammation (increased plasma IL-1ß level, aortic pro-inflammatory gene expression, and MOMA-2-positive cells in the BCA) after 20 weeks of HFD. Differences between the HGHCi and HCi HFD models were confirmed using RNA-seq analysis of aortic tissue, revealing that significantly more genes were dysregulated in mice with combined hyperlipidemia and hyperglycemia than in the hyperlipidemia-only group. The HGHCi-associated genes were related to pathways regulating inflammation (increased Cd68, iNos, and Tnfa expression) and extracellular matrix degradation (Adamts4 and Mmp14). When comparing HFD with PD, the PD aggravated atherosclerosis to a greater extent in mice and showed plaque formation after 8 weeks. Hyperlipidemic and hyperglycemic mice fed a PD (HGHCi PD) showed less collagen (Sirius red) and increased inflammation (CD68-positive cells) within aortic plaques than hyperlipidemic mice (HCi PD). HGHCi-PD mice represent a directly inducible hyperglycemic atherosclerosis model compared with HFD-fed mice, in which atherosclerosis is severe by 8 weeks. Conclusion: We established a nongenetically inducible mouse model allowing comparative analyses of atherosclerosis in HCi and HGHCi conditions and its modification by diet, allowing analyses of multiple metabolic hits in mice.

19.
Int J Mol Sci ; 22(18)2021 Sep 13.
Article in English | MEDLINE | ID: mdl-34576036

ABSTRACT

Procoagulant extracellular vesicles (EV) and platelet activation have been associated with gestational vascular complications. EV-induced platelet-mediated placental inflammasome activation has been shown to cause preeclampsia-like symptoms in mice. However, the effect of EV-mediated placental thrombo-inflammation on trophoblast differentiation remains unknown. Here, we identify that the EV-induced thrombo-inflammatory pathway modulates trophoblast morphology and differentiation. EVs and platelets reduce syncytiotrophoblast differentiation while increasing giant trophoblast and spongiotrophoblast including the glycogen-rich cells. These effects are platelet-dependent and mediated by the NLRP3 inflammasome. In humans, inflammasome activation was negatively correlated with trophoblast differentiation marker GCM1 and positively correlated with blood pressure. These data identify a crucial role of EV-induced placental thrombo-inflammation on altering trophoblast differentiation and suggest platelet activation or inflammasome activation as a therapeutic target in order to achieve successful placentation.


Subject(s)
Extracellular Vesicles/genetics , Inflammation/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , Pregnancy Complications, Cardiovascular/genetics , Animals , Blood Platelets/metabolism , Blood Platelets/pathology , Cell Differentiation/genetics , DNA-Binding Proteins/genetics , Disease Models, Animal , Extracellular Vesicles/metabolism , Female , Humans , Inflammasomes/genetics , Inflammation/metabolism , Inflammation/pathology , Mice , Platelet Activation/genetics , Pregnancy , Pregnancy Complications, Cardiovascular/pathology , Transcription Factors/genetics , Trophoblasts/metabolism , Trophoblasts/pathology
20.
J Am Soc Nephrol ; 32(12): 3066-3079, 2021 12 01.
Article in English | MEDLINE | ID: mdl-34479965

ABSTRACT

BACKGROUND: Maladaptive endoplasmic reticulum stress signaling in diabetic kidney disease (DKD) is linked to increased glomerular and tubular expression of the cell-death-promoting transcription factor C/EBP homologous protein (CHOP). Here, we determined whether locked nucleic acid (LNA)-modified antisense oligonucleotides (ASOs) targeting CHOP ameliorate experimental DKD. METHODS: We determined the efficacy of CHOP-ASO in the early and late stages of experimental DKD (in 8- or 16-week-old db/db mice, respectively) alone or with an angiotensin-converting enzyme inhibitor (ACEi), after an in vivo dose-escalation study. We used renal functional parameters and morphologic analyses to assess the effect of CHOP-ASO and renal gene-expression profiling to identify differentially regulated genes and pathways. Several human CHOP-ASOs were tested in hyperglycemia-exposed human kidney cells. RESULTS: CHOP-ASOs efficiently reduced renal CHOP expression in diabetic mice and reduced markers of DKD at the early and late stages. Early combined intervention (CHOP-ASO and ACEi) efficiently prevented interstitial damage. At the later timepoint, the combined treatment reduced indices of both glomerular and tubular damage more efficiently than either intervention alone. CHOP-ASO affected a significantly larger number of genes and disease pathways, including reduced sodium-glucose transport protein 2 (Slc5a2) and PROM1 (CD133). Human CHOP-ASOs efficiently reduced glucose-induced CHOP and prevented death of human kidney cells in vitro . CONCLUSIONS: The ASO-based approach efficiently reduced renal CHOP expression in a diabetic mouse model, providing an additional benefit to an ACEi, particularly at later timepoints. These studies demonstrate that ASO-based therapies efficiently reduce maladaptive CHOP expression and ameliorate experimental DKD.


Subject(s)
Diabetes Mellitus, Experimental , Diabetic Nephropathies , Mice , Humans , Animals , Diabetic Nephropathies/drug therapy , Diabetic Nephropathies/etiology , Diabetic Nephropathies/prevention & control , Diabetes Mellitus, Experimental/complications , Kidney Glomerulus , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Kidney , Oligonucleotides, Antisense/pharmacology
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