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Background: The consumption of artificially sweetened beverages (ASBs) has been linked to metabolic alterations. The effect of reducing the regular consumption of these beverages on the metabolism is currently unknown., Objective: To evaluate the effect of reducing consumption of ASBs on the metabolism in overweight young adults., Design: A randomised, single-blind, controlled, 12-week, clinical trial was performed in overweight young adults who regularly consume ASBs. The 45 subjects who participated in the study were randomly divided into two groups: (1) control group (n=21) and (2) intervention group (no intake of ASBs, n=24). Body weight and composition, fasting plasma concentrations of glucose, triglycerides, insulin, cholesterol, low-density lipoproteins and high-density lipoproteins were measured at the beginning and end of the study. and the HOMA-IR was calculated., Results: At the end of 12 weeks, the intervention group showed a significant decrease (as opposed to an increase in the control group) in the percentage of change in body weight (-1.22% vs 1.31%, p<0.004), body fat (-6.28% vs 6.15%, p<0.001) and insulin resistance index (-12.06 vs 38.21%, p<0.00002), as well as in levels of glucose (-4.26% vs 0.51%, p<0.05), triglycerides (-14.74% vs 19.90%, p<0.006), insulin (-8.02% vs 39.23%, p<0.00005), cholesterol (-8.71% vs 0.77%, p<0.01) and LDL (-9.46% vs 9.92%, p<0.004)., Conclusion: A reduction in habitual consumption of ASBs in overweight young adults decreases biochemical measurements, body weight and composition, suggesting a participation in the metabolic processes., (Copyright © 2021 SEEN and SED. Published by Elsevier España, S.L.U. All rights reserved.)

Background: The consumption of artificially sweetened beverages (ASBs) has been linked to metabolic alterations. The effect of reducing the regular consumption of these beverages on the metabolism is currently unknown., Objective: To evaluate the effect of reducing consumption of ASBs on the metabolism in overweight young adults., Design: A randomised, single-blind, controlled, 12-week, clinical trial was performed in overweight young adults who regularly consume ASBs. The 45 subjects who participated in the study were randomly divided into two groups: (1) control group (n=21) and (2) intervention group (no intake of ASBs, n=24). Body weight and composition, fasting plasma concentrations of glucose, triglycerides, insulin, cholesterol, low-density lipoproteins and high-density lipoproteins were measured at the beginning and end of the study. and the HOMA-IR was calculated., Results: At the end of 12 weeks, the intervention group showed a significant decrease (as opposed to an increase in the control group) in the percentage of change in body weight (-1.22% vs 1.31%, p<0.004), body fat (-6.28% vs 6.15%, p<0.001) and insulin resistance index (-12.06 vs 38.21%, p<0.00002), as well as in levels of glucose (-4.26% vs 0.51%, p<0.05), triglycerides (-14.74% vs 19.90%, p<0.006), insulin (-8.02% vs 39.23%, p<0.00005), cholesterol (-8.71% vs 0.77%, p<0.01) and LDL (-9.46% vs 9.92%, p<0.004)., Conclusion: A reduction in habitual consumption of ASBs in overweight young adults decreases biochemical measurements, body weight and composition, suggesting a participation in the metabolic processes., (Copyright © 2021 SEEN y SED. Publicado por Elsevier España, S.L.U. All rights reserved.)

Aims: atherosclerotic plaque development can conclude with a thrombotic acute event triggered by plaque rupture/erosion. Tumour necrosis factor-like weak inducer of apoptosis (TWEAK) is a member of the tumour necrosis factor superfamily that, through its receptor, fibroblast growth factor-inducible 14 (Fn14), participates in vascular remodelling, increasing vascular inflammatory responses and atherosclerotic lesion size in ApoE knockout mice. However, the role of the TWEAK-Fn14 axis in thrombosis has not been previously investigated., Methods and Results: we have examined whether TWEAK regulates expression of prothrombotic factors such as tissue factor (TF) and plasminogen activator inhibitor 1 (PAI-1) in atherosclerotic plaques as well as in human aortic vascular smooth muscle cells (hASMCs) in culture. Expression of TF and PAI-1 was colocalized and positively correlated with Fn14 in human carotid atherosclerotic plaques. In vitro, TWEAK increased TF and PAI-1 mRNA, protein expression and activity in hASMCs. All these effects were reversed using blocking anti-TWEAK monoclonal antibody, anti-Fn14 antibody or Fn14 small interfering RNA, indicating that TWEAK increased the prothrombotic state through its receptor, Fn14. Finally, ApoE(-/-) mice were fed a hyperlipidaemic diet for 10 weeks, then randomized and treated with saline (controls), TWEAK (10 microg/kg/day), anti-TWEAK neutralizing monoclonal antibody (1000 µg/kg/day), or non-specific immunoglobulin G (1000 microg/kg/day) daily for 9 days. Systemic TWEAK injection increased TF and PAI-1 protein expression in the aortic root of ApoE(-/-) mice. Conversely, TWEAK blocking antibodies diminished both TF and PAI-1 protein expression compared with non-specific immunoglobulin G-treated mice., Conclusions: our results indicate that the TWEAK-Fn14 axis can regulate activation of TF and PAI-1 expression in vascular cells. TWEAK-Fn14 may be a therapeutic target in the prothrombotic complications associated with atherosclerosis.

Aims: Heat shock protein 90 (HSP90) is a ubiquitous chaperone involved in the folding, activation, and assembly of many proteins. HSP90 inhibitors [17-allylamino-17-demethoxygeldamycin (17-AAG)/17-dimethyl aminothylamino-17-demethoxygeldanamycin hydrochloride (17-DMAG)] bind to and inactivate HSP90, increasing the heat shock response and suppressing different signalling pathways. We aim to investigate the effect of HSP90 inhibitors in the modulation of inflammatory responses during atherogenesis., Methods and Results: In human atherosclerotic plaques, HSP90 immunostaining was increased in inflammatory regions and in plaques characterized by lower cap thickness. In cultured human macrophages and vascular smooth muscle cells, treatment with either 17-AAG or 17-DMAG increased HSP70 expression and reduced transcription factor [signal transducers and activators of transcription (STAT) and nuclear factor-kappaB (NF-kappaB)] activation and chemokine expression induced by proinflammatory cytokines. In vivo, hyperlipidaemic ApoE(-/-) mice were randomized to 17-DMAG (2 mg/kg every 2 days, n = 11) or vehicle injected (n = 9) during 10 weeks. Atherosclerotic plaques of mice treated with 17-DMAG displayed increased HSP70 expression and diminished NF-kappaB and STAT activation, along with decreased lesion, lipid, and macrophage content, compared with vehicle-injected mice. In addition, treatment with 17-DMAG significantly reduced monocyte chemoattractant protein-1 levels, both in plaques and in plasma., Conclusion: HSP90 expression is associated with features of plaque instability in advanced human lesions. HSP90 inhibitors reduce inflammatory responses in atherosclerosis, suggesting that HSP90 could be a novel therapeutic target in atherosclerosis.

Objective: Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) is a member of the tumor necrosis factor superfamily of cytokines. TWEAK binds and activates the Fn14 receptor, and may regulate apoptosis, inflammation, and angiogenesis, in different pathological conditions. We have evaluated the effect of exogenous TWEAK administration as well as the role of endogenous TWEAK on proinflammatory cytokine expression and vascular and renal injury severity in hyperlipidemic ApoE-knockout mice., Methods and Results: ApoE(-/-) mice were fed with hyperlipidemic diet for 4 to 10 weeks, then randomized and treated with saline (controls), TWEAK (10 microg/kg/d), anti-TWEAK neutralizing mAb (1000 microg/kg/d), TWEAK plus anti-TWEAK antibody (10 microg TWEAK +1000 microg anti-TWEAK/kg/d), or nonspecific IgG (1000 microg/kg/d) daily for 9 days. In ApoE(-/-) mice, exogenous TWEAK administration in ApoE(-/-) mice induced activation of NF-kappaB, a key transcription factor implicated in the regulation of the inflammatory response, in vascular and renal lesions. Furthermore, TWEAK treatment increased chemokine expression (RANTES and MCP-1), as well as macrophage infiltration in atherosclerotic plaques and renal lesions. These effects were associated with exacerbation of vascular and renal damage. Conversely, treatment of ApoE(-/-) mice with an anti-TWEAK blocking mAb decreased NF-kappaB activation, proinflammatory cytokine expression, macrophage infiltration, and vascular and renal injury severity, indicating a pathological role for endogenous TWEAK. Finally, in murine vascular smooth muscle cells or tubular cells, either ox-LDL or TWEAK treatment increased expression and secretion of both RANTES and MCP-1. Furthermore, ox-LDL and TWEAK synergized for induction of MCP-1 and RANTES expression and secretion., Conclusions: Our results suggest that TWEAK exacerbates the inflammatory response associated with a high lipid-rich diet. TWEAK may be a novel therapeutic target to prevent vascular and renal damage associated with hyperlipidemia.

IgG Fc receptors (FcgammaRs) play a role in activating the immune system and in maintaining peripheral tolerance, but their role in atherosclerosis is unknown. We generated double-knockout (DKO) mice by crossing apolipoprotein E-deficient mice (apoE(-/-)) with FcgammaR gamma chain-deficient mice (gamma(-/-)). The size of atherosclerotic lesions along the aorta was approximately 50% lower in DKO compared with apoE(-/-) control mice, without differences in serum lipid levels. The macrophage and T-cell content of lesions in the DKO were reduced by 49+/-6% and 56+/-8%, respectively, compared with the content in apoE(-/-) lesions. Furthermore, the expression of monocyte chemoattractant protein-1 (MCP-1), RANTES (Regulated on Activated Normal T-cell Expressed and Secreted), and intercellular adhesion molecule-1 (ICAM-1) and the activation of nuclear factor-kappaB (NF-kappaB) were significantly reduced in aortic lesions from DKO mice. In vitro, vascular smooth muscle cells (VSMCs) from both gamma(-/-) and DKO mice failed to respond to immune complexes, as shown by impaired chemokine expression and NF-kappaB activation. ApoE(-/-) mice have higher levels of activating FcgammaRI and FcgammaRIIIA, and inhibitory FcgammaRIIB, compared with wild-type mice. The DKO mice express only the inhibitory FcgammaRIIB receptor. We conclude that FcgammaR deficiency limits development and progression of atherosclerosis. In addition to leukocytes, FcgammaR activation in VSMCs contributes to the inflammatory process, in part, by regulating chemokine expression and leukocyte invasion of the vessel wall. These results underscore the critical role of FcgammaRs in atherogenesis and support the use of immunotherapy in the treatment of this disease.

Objective: Activation of transcription factor NF-kappaB is an important step in the development of vascular damage, because it controls inducible genes, including many inflammatory mediators. The pharmacological modulation of this process is the main objective in the design of new therapies for atherosclerosis. In this work we analyzed the effects of the natural compound parthenolide (PTN), an NF-kappaB inhibitor., Methods and Results: In vascular smooth muscle cells (VSMCs) and monocytes stimulated with lipopolysaccharide (LPS), nontoxic doses of PTN reduced IkappaBalpha degradation, NF-kappaB activation, and MCP-1 expression, without inhibiting AP-1 and MAPK. In apoE mice, treatment with low (2 mg/kg, 20 weeks), medium (4 mg/kg, 10 weeks), and high (10 mg/kg, 10 weeks) dose of PTN reduced the size of aortic lesion, decreased macrophage, and increased VSMC content in the lesions. Treated mice showed reduced serum levels of MCP-1 and attenuated NF-kappaB activity, but not AP-1, in the lesions. Moreover, PTN affects neither apoptotic cell death nor oxidative stress in cultured cells and mice., Conclusions: NF-kappaB inhibition by PTN retards atherosclerotic lesions in apoE mice, by reducing lesion size and changing plaque composition. This natural compound could represent a novel therapeutic approach to inflammation during vascular damage.

The mesangium occupies a central anatomical position in the glomerulus, and also plays an important regulatory role in immune-mediated glomerular diseases, with an active participation in the response to local inflammation. In general, the mesangial cell responses to the pathological stimuli are associated with the main events of glomerular injury: leukocyte infiltration, cell proliferation and fibrosis. Leukocyte migration and infiltration into the glomerulus is responsible for the initiation and amplification of glomerular injury, and is mediated by adhesion molecules and chemokines, which can be locally synthesized by mesangial cells. The increase in mesangial cell number is also due to proliferation of intrinsic mesangial cell population. Regulatory mechanisms of mesangial cell replication include a complex array of factors which control cell proliferation, survival and apoptosis. Mesangial matrix accumulation leading to glomerulosclerosis, is a consequence of an imbalance between matrix production and degradation, and is controlled by growth factors and pro-inflammatory cytokines. The initial phase of immune-mediated glomerular inflammation depends on the interaction of immune complexes with specific Fc receptors in infiltrating leukocytes and resident mesangial cells, the ability of immune complexes to activate complement system, and on local inflammatory processes. Activated mesangial cells then produce many inflammatory mediators leading to amplification of the injury. This review will focus on the biological functions of mesangial cells that contribute to glomerular injury, with special attention to immune-mediated glomerulonephritis. Furthermore, new therapies based on the pathophysiology of the mesangial cell that are being developed in experimental models are also proposed.

Suppressors of cytokine signaling (SOCS) family is constituted by cytokine-inducible proteins that modulate receptor signal transduction via tyrosine kinases, mainly the Janus kinase-signal transducers and activators of transcription (JAK-STAT) pathway. Differential SOCS expression was noted in renal cells that were incubated with inflammatory stimuli, but the role of SOCS in the pathogenesis of renal diseases is not yet well defined. Because angiotensin II (Ang II) plays a key role in renal disease, SOCS proteins were studied as a novel mechanism involved in the negative regulation of Ang II-mediated processes. Systemic Ang II infusion for 3 d increased the renal mRNA expression of SOCS-3 and SOCS-1. SOCS protein synthesis was found in glomerular mesangial area and tubules. In cultured mesangial cells and tubular epithelial cells, Ang II induced a rapid and transient SOCS-3 and SOCS-1 expression in parallel with JAK2 and STAT1 activation. In both cell types, overexpression of SOCS proteins prevented the STAT activation in response to Ang II. SOCS expression observed in Ang II-infused rats and in Ang II-stimulated cells was significantly inhibited by treatment with AT(1) but not AT(2) receptor antagonist and was attenuated in mesangial cells from AT(1a)-deficient mice, demonstrating the implication of AT(1) in those responses. In SOCS-3 knockdown studies, antisense oligonucleotides inhibited the expression of SOCS-3 and increased the Ang II-induced STAT activation and c-Fos/c-Jun expression, then resulting in a more severe renal damage. These results suggest that SOCS proteins may act as negative regulators of Ang II signaling in renal cells and implicate SOCS as important modulators of renal damage.

Suppressors of cytokine signaling (SOCS) are cytokine-inducible proteins that modulate receptor signaling via tyrosine kinase pathways. We investigate the role of SOCS in renal disease, analyzing whether SOCS regulate IgG receptor (FcgammaR) signal pathways. In experimental models of immune complex (IC) glomerulonephritis, the renal expression of SOCS family genes, mainly SOCS-3, significantly increased, in parallel with proteinuria and renal lesions, and the proteins were localized in glomeruli and tubulointerstitium. Induction of nephritis in mice with a deficiency in the FcgammaR gamma-chain (gamma(-/-) mice) resulted in a decrease in the renal expression of SOCS-3 and SOCS-1. Moreover, blockade of FcgammaR by Fc fragment administration in rats with ongoing nephritis selectively inhibited SOCS-3 and SOCS-1, without affecting cytokine-inducible Src homology 2-containing protein and SOCS-2. In cultured human mesangial cells (MC) and monocytes, IC caused a rapid and transient induction of SOCS-3 expression. Similar kinetics was observed for SOCS-1, whereas SOCS-2 expression was very low. MC from gamma(-/-) mice failed to respond to IC activation, confirming the participation of FcgammaR. Interestingly, IC induced tyrosine phosphorylation of SOCS-3 and Tec tyrosine kinase, and both proteins coprecipitated in lysates from IC-stimulated MC, suggesting intracellular association. IC also activated STAT pathway in MC, which was suppressed by SOCS overexpression, mainly SOCS-3. In SOCS-3 knockdown studies, specific antisense oligonucleotides inhibited mesangial SOCS-3 expression, leading to an increase in the IC-induced STAT activation. Our results indicate that SOCS may play a regulatory role in FcgammaR signaling, and implicate SOCS as important modulators of cell activation during renal inflammation.

In immune complex (IC) diseases, FcR are essential molecules facilitating polymorphonuclear cell (PMN) recruitment and effector functions at the IC site. Although FcR-dependent initial tethering and FcR/integrin-dependent PMN accumulation were postulated, their underlying mechanisms remain unclear. We here addressed potential mechanisms involved in PMN recruitment in acute IC glomerulonephritis (nephrotoxic nephritis). Since some renal cells may be recruited from bone marrow (BM) lineages, reconstitution studies with BM chimeras and PMN transfer between wild-type (WT) and FcR-deficient mice (gamma(-/-)) were performed. Severe glomerular damage was induced in WT and W gamma chimeras (BM from WT to irradiated gamma(-/-)), while it was absent in gamma(-/-) and gamma W chimeras (gamma(-/-) BM to WT). Moreover, WT PMN transfer, but not gamma(-/-) PMN, reconstituted the disease in gamma(-/-), indicating that FcR on resident cells is not a prerequisite for PMN recruitment in this disease. Surprisingly, transferred WT PMN were recruited coincidentally with NF-kappa B activation and TNF-alpha overexpression even in glomeruli with preformed IC (nephrotoxic Ab administered 3 days previously), suggesting that PMN can initially be recruited via its own FcR without previous chemoattractant release. Furthermore, H(2)O(2) inhibition by catalase attenuated the acute WT PMN recruitment and the induction of NF-kappa B and TNF-alpha much more than integrin (CD18) blockade, indicating a role for the respiratory burst before integrin-dependent accumulation. In coculture experiments with IC-stimulated PMN and glomeruli, PMN caused acute glomerular TNF-alpha expression predominantly via FcR-mediated H(2)O(2) production. In conclusion, glomerular IC, even preformed, can cause PMN recruitment and injury through PMN FcR-mediated respiratory burst during initial PMN tethering to IC.

Background: Interaction of deposited immune complexes (IC) with Fc receptors (FcR) on tissue cells elicits the release of inflammatory mediators leading to tissue damage. Nitric oxide (NO) radicals generated by inducible NO synthase (iNOS) are important mediators in inflammatory processes. To analyze the role of NO in IC-mediated glomerular inflammation, we studied the in vitro and in vivo expression of iNOS in renal cells [resident mesangial cells (MC), and infiltrating monocytes] induced by IC, and the possible intermediate steps between FcR occupancy and iNOS induction., Methods: MC and monocytes were stimulated with IgG- and IgA-containing IC, and NO production (nitrite accumulation), iNOS transcription (luciferase assay) and their expression was measured by RT-PCR and Western blot. The involvement of FcR, transcription factor nuclear factor-kappaB (NF-kappaB), and protein kinases was assessed by using Fc fragments and specific inhibitors. Immune glomerulonephritis was induced in rats, and iNOS expression and NF-kappaB activation were analyzed., Results: In MC and monocytes, IC enhanced iNOS transcription/expression and NO generation, which were attenuated by specific inhibitors of NF-kappaB. In addition, mitogen-activated protein kinase (MAPK) inhibitors decreased NO production, but did not interfere with NF-kappaB activity, suggesting that both pathways may converge downstream in the induction of iNOS. In experimental immune glomerulonephritis, increased iNOS expression correlated with proteinuria levels, and appeared colocalized with NF-kappaB in glomerular and infiltrating cells. Treatment of animals and cells with Fc fragments prevented iNOS induction and NF-kappaB activation by IC., Conclusions: These results indicate that IC, through activation of FcR, induce iNOS expression in renal resident and recruited cells by mechanisms involving MAPK and NF-kappaB, and support the idea of the important role of local NO generation in IC-mediated glomerular injury.

FcR provides a critical link between ligands and effector cells in immune complex diseases. Emerging evidence reveals that angiotensin (Ang)II exerts a wide variety of cellular effects and contributes to the pathogenesis of inflammatory diseases. In anti-glomerular basement membrane Ab-induced glomerulonephritis (GN), we have previously noted that FcR-deficient mice (gamma(-/-)) surviving from lethal initial damage still developed mesangial proliferative GN, which was drastically prevented by an AngII type 1 receptor (AT1) blocker. We further examined the mechanisms by which renin-Ang system (RAS) participates in this immune disease. Using bone marrow chimeras between gamma(-/-) and AT1(-/-) mice, we found that glomerular injury in gamma(-/-) mice was associated with CD4(+) T cell infiltration depending on renal AT1-stimulation. Based on findings in cutaneous delayed-type hypersensitivity, we showed that AngII-activated renal resident cells are responsible for the recruitment of effector T cells. We next examined the chemotactic activity of AngII-stimulated mesangial cells, as potential mechanisms coupling RAS and cellular immunity. Chemotactic activity for T cells and Th1-associated chemokine (IFN-gamma-inducible protein-10 and macrophage-inflammatory protein 1alpha) expression was markedly reduced in mesangial cells from AT1(-/-) mice. Moreover, this activity was mainly through calcineurin-dependent NF-AT. Although IFN-gamma-inducible protein-10 was NF-kappaB-dependent, macrophage-inflammatory protein 1alpha was dominantly regulated by NF-AT. Furthermore, AT1-dependent NF-AT activation was observed in injured glomeruli by Southwestern histochemistry. In conclusion, our data indicate that local RAS activation, partly via the local NF-AT pathway, enhances the susceptibility to T cell-mediated injury in anti-glomerular basement membrane Ab-induced GN. This novel mechanism affords a rationale for the use of drugs interfering with RAS in immune renal diseases.

Nuclear factor (NF)-kappa B regulates several genes implicated in the inflammatory response and represents an interesting therapeutic target. We examined the effects of gliotoxin (a fungal metabolite) and parthenolide (a plant extract), which possess anti-inflammatory activities in vitro, on the progression of experimental glomerulonephritis. In the anti-Thy 1.1 rat model, gliotoxin (75 micro g/rat/day, 10 days, n = 18 rats) markedly reduced proteinuria, glomerular lesions, and monocyte infiltration. In anti-mesangial cell nephritis in mice, parthenolide (70 micro g/mouse/day, 7 days, n = 17 mice) significantly decreased proteinuria, hematuria, and glomerular proliferation. NF-kappa B activity, localized in glomerular and tubular cells, was attenuated by either gliotoxin or parthenolide, in association with diminished renal expression of monocyte chemoattractant protein-1 and inducible nitric oxide synthase. In cultured mesangial cells and monocytes, gliotoxin and parthenolide inhibited NF-kappa B activation and expression of inflammatory genes induced by lipopolysaccharide and cytokines, by blocking the phosphorylation/degradation of the I kappa B(alpha) subunit. In summary, gliotoxin and parthenolide prevent proteinuria and renal lesions by inhibiting NF-kappa B activation and expression of regulated genes. This may represent a novel approach for the treatment of immune and inflammatory renal diseases.