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Metabolic syndrome (MetS) is a complex, emerging epidemic which disrupts the metabolic homeostasis of several organs, including liver, heart, pancreas, and adipose tissue. While studies have been conducted in these research areas, the pathogenesis and mechanisms of MetS remain debatable. Lines of evidence show that physiological systems, such as the renin–angiotensin system (RAS) and autophagy play vital regulatory roles in MetS. RAS is a pivotal system known for controlling blood pressure and fluid balance, whereas autophagy is involved in the degradation and recycling of cellular components, including proteins. Although RAS is activated in MetS, the interrelationship between RAS and autophagy varies in glucose homeostatic organs and their cross talk is poorly understood. Interestingly, autophagy is attenuated in the liver during MetS, whereas autophagic activity is induced in adipose tissue during MetS, indicating tissue-specific discordant roles. We discuss in vivo and in vitro studies conducted in metabolic tissues and dissect their tissue-specific effects. Moreover, our review will focus on the molecular mechanisms by which autophagy orchestrates MetS and the ways future treatments could target RAS in order to achieve metabolic homeostasis.

Macrophages may be a crucial aspect of diabetic complications associated with the inflammatory response. In this study, we examined how hyperglycaemia, a common aspect of diabetes, modulates bone marrow-derived macrophages (BMDMs) under an inflammatory stimulus. To perform this study, BMDMs from non-diabetic and diabetic (60 mg/kg alloxan, i.v.) male C57BL/6 mice (CEUA/FCF/USP-488) were cultured under normal (5.5 mM) and high glucose (HG, 25 or 40 mM) conditions and stimulated or not stimulated with lipopolysaccharide (LPS, 100 ng/mL). Compared to the BMDMs from the normoglycaemic mice, the LPS-stimulated BMDMs from the diabetic mice presented reduced TLR4 expression on the cell surface, lower phagocytic capacity, and reduced secretion of NO and lactate but greater oxygen consumption and greater phosphorylation of p46 SAPK/JNK, p42 ERK MAPK, pAKT and pPKC-δ. When the BMDMs from the non-diabetic mice were cultured under high-glucose conditions and stimulated with LPS, TLR4 expression was reduced on the cell surface and NO and H2O2 levels were reduced. In contrast, the diabetic BMDMs cultured under high glucose conditions presented increased levels of lactate and reduced phosphorylation of AKT, PKC-δ and p46 SAPK/JNK but enhanced phosphorylation of the p46 subunit of SAPK/JNK after LPS stimulation. High glucose levels appear to modify macrophage behaviour, affecting different aspects of diabetic and healthy BMDMs under the same LPS stimulus. Thus, hyperglycaemia leaves a glucose legacy, altering the basal steady state of macrophages.

Glucocorticoid (GC)-induced leucine zipper (GILZ) has been shown to mediate or mimic several actions of GC. This study assessed the role of GILZ in self-resolving and GC-induced resolution of neutrophilic inflammation induced by LPS in mice. GILZ expression was increased during the resolution phase of LPS-induced pleurisy, especially in macrophages with resolving phenotypes. Pretreating LPS-injected mice with trans-activator of transcription peptide (TAT)–GILZ, a cell-permeable GILZ fusion protein, shortened resolution intervals and improved resolution indices. Therapeutic administration of TAT-GILZ induced inflammation resolution, decreased cytokine levels, and promoted caspase-dependent neutrophil apoptosis. TAT-GILZ also modulated the activation of the survival-controlling proteins ERK1/2, NF-κB and Mcl-1. GILZ deficiency was associated with an early increase of annexin A1 (AnxA1) and did not modify the course of neutrophil influx induced by LPS. Dexamethasone treatment resolved inflammation and induced GILZ expression that was dependent on AnxA1. Dexamethasone-induced resolution was not altered in GILZ−/− mice due to compensatory expression and action of AnxA1. Our results show that therapeutic administration of GILZ efficiently induces a proapoptotic program that promotes resolution of neutrophilic inflammation induced by LPS. Alternatively, a lack of endogenous GILZ during the resolution of inflammation is compensated by AnxA1 overexpression.

Paracoccidioidomycosis, a key issue for Brazilian health service, can be aggravated in patients with impaired immunological responses, such as diabetic patients. We evaluated the role of insulin in inflammatory parameters in diabetic and nondiabetic mice using a systemic mycosis Paracoccidioides brasiliensis (Pb) model. Diabetic C57BL-6 mice and controls were infected with Pb18 and treated with insulin for 12 days prior to experiments. After 55 days, infected diabetic mice exhibited fewer leukocytes in both peritoneal lavage fluid (PeLF) and bronchoalveolar lavage fluid and reduced secretion of interleukin- (IL-) 6 in lungs. In addition, diabetic mice presented a reduced influx of TCD4+ cells, TCD8+ cells, B lymphocytes, NK cells, and dendritic cells compared to control infected groups. Insulin treatment restored the leukocyte number in PeLF and restored the presence of B lymphocytes, dendritic cells, and NK cells in lungs of diabetic animals. The data suggest that diabetic mice present impaired immunological response to Pb18 infection and insulin modulates inflammation by reducing IL-6 levels in lung and CINC-1 levels in spleen and liver homogenates, restoring leukocyte concentrations in PeLF and also restoring populations of dendritic cells and B lymphocytes in lungs of diabetic mice, permitting the host to better control the infection.

PURPOSE: To investigate the effects of pentoxifylline (PTX) in experimental acute pancreatitis (AP) starting drug administration after the induction of the disease. METHODS: One hundred male Wistar rats were submitted to taurocholate-induced AP and divided into three groups: Group Sham: sham-operated rats, Group Saline: AP plus saline solution, and Group PTX: AP plus PTX. Saline solution and PTX were administered 1 hour after induction of AP. At 3 hours after AP induction, peritoneal levels of tumor necrosis factor (TNF)-α, and serum levels of interleukin (IL)-6 and IL-10 levels were assayed by Enzyme-Linked Immunosorbent Assay (ELISA). Determinations of lung myeloperoxidase activity (MPO), histological analysis of lung and pancreas, and mortality study were performed. RESULTS: PTX administration 1 hour after induction of AP caused a significant decrease in peritoneal levels of TNF-α and in serum levels of IL-6 and IL-10 when compared to the saline group. There were no differences in lung MPO activity between the two groups with AP. A decrease in mortality was observed in the PTX treatment compared to the saline group. CONCLUSIONS: Administration of PTX after the onset of AP decreased the systemic levels of proinflammatory cytokines, raising the possibility that there is an early therapeutic window for PTX after the initiation of AP.

BACKGROUND AND PURPOSE The serine and cysteine peptidase inhibitor, BbCI, isolated from Bauhinia bauhinioides seeds, is similar to the classical plant Kunitz inhibitor, STI, but lacks disulphide bridges and methionine residues. BbCI blocks activity of the serine peptidases, elastase (Kiapp 5.3 nM) and cathepsin G (Kiapp 160.0 nM), and the cysteine peptidase cathepsin L (Kiapp 0.2 nM). These three peptidases play important roles in the inflammatory process. EXPERIMENTAL APPROACH We measured the effects of BbCI on paw oedema and on leucocyte accumulation in pleurisy, both induced by carrageenan. Leucocyte–endothelial cell interactions in scrotal microvasculature in Wistar rats were investigated using intravital microscopy. Cytokine levels in pleural exudate and serum were measured by elisa. KEY RESULTS Pretreatment of the animals with BbCI (2.5 mg·kg−1), 30 min before carrageenan-induced inflammation, effectively reduced paw oedema and bradykinin release, neutrophil migration into the pleural cavity. The number of rolling, adhered and migrated leucocytes at the spermatic fascia microcirculation following carrageenan injection into the scrotum were reduced by BbCI pretreatment. Furthermore, levels of the rat chemokine cytokine-induced neutrophil chemo-attractant-1 were significantly reduced in both pleural exudates and serum from animals pretreated with BbCI. Levels of interleukin-1β or tumour necrosis factor-α, however, did not change. CONCLUSIONS AND IMPLICATIONS Taken together, our data suggest that the anti-inflammatory properties of BbCI may be useful in investigations of other pathological processes in which human neutrophil elastase, cathepsin G and cathepsin L play important roles.

Background: Allergic lung inflammation is impaired in diabetic rats and is restored by insulin treatment. In the present study we investigated the effect of insulin on the signaling pathways triggered by allergic inflammation in the lung and the release of selected mediators. Methods: Diabetic male Wistar rats (alloxan, 42 mg/kg, i.v., 10 days) and matching controls were sensitized by s.c. injections of ovalbumin (OA) in aluminium hydroxide, 14 days before OA (1 mg/0.4 ml) or saline intratracheal challenge. A group of diabetic rats were treated with neutral protamine Hagedorn insulin (NPH, 4 IU, s.c.), 2 h before the OA challenge. Six hours after the challenge, bronchoalveolar lavage (BAL) was performed for mediator release and lung tissue was homogenized for Western blotting analysis of signaling pathways. Results: Relative to non-diabetic rats, the diabetic rats exhibited a significant reduction in OA-induced phosphorylation of the extracellular signal-regulated kinase (ERK, 59%), p38 (53%), protein kinase B (Akt, 46%), protein kinase C (PKC)- α (63%) and PKC-δ (38%) in lung homogenates following the antigen challenge. Activation of the NF-ĸB p65 subunit and phosphorylation of IĸBα were almost suppressed in diabetic rats. Reduced expression of inducible nitric oxide synthase (iNOS, 32%) and cyclooxygenase-2 (COX-2, 46%) in the lung homogenates was also observed. The BAL concentration of prostaglandin (PG)-E2, nitric oxide (NO) and interleukin (IL)-6 was reduced in diabetic rats (74%, 44% and 65%, respectively), whereas the cytokine-induced neutrophil chemoattractant (CINC)-2 concentration was not different from the control animals. Treatment of diabetic rats with insulin completely or partially restored all of these parameters. This protocol of insulin treatment only partially reduced the blood glucose levels. Conclusion: The data presented show that insulin regulates MAPK, PI3K, PKC and NF-ĸB pathways, the expression of the inducible enzymes iNOS and COX-2, and the levels of NO, PGE2 and IL-6 in the early phase of allergic lung inflammation in diabetic rats. It is suggested that insulin is required for optimal transduction of the intracellular signals that follow allergic stimulation.

To investigate the allergic reaction in neonatal streptozotocin (nSTZ)-induced diabetes mellitus.Male newborn Wistar rats were made diabetic by the injection of streptozotocin (160 mg/kg, i. p.) and used 8 weeks thereafter.Animals were sensitized against ovalbumin (OA, 50 microg and Al(OH)3, 5 mg, s. c.) and challenged 14 or 21 days thereafter.OA-induced airway inflammation and OA-induced pleurisy models were used to investigate leukocyte migration (total and differential leukocyte counts) and lung vascular permeability (Evans blue dye extravasation).nSTZ-diabetic rats presented glucose intolerance and insulin resistance. Relative to controls, nSTZ rats exhibited a 30% to 50% reduction in lung vascular permeability. Leukocyte infiltration in both models of allergen-induced inflammation, and number of pleural mast cells did not differ between groups.Data suggest that the reduction of allergic inflammatory reactions in nSTZ rats is restricted to microvascular dysfunctions and associated, probably, with insulin resistance in lung microvascular endothelium.

Background We have previously shown that diabetic rats are more susceptible to sepsis, but that the Acute lung injury (ALI) secondary to sepsis is less intense than in non-diabetics. In the present study, we further investigated the ALI-secondary to sepsis in diabetic rats and the effect of insulin treatment. Methods Diabetes was induced in male Wistar rats by alloxan and sepsis by cecal ligation and puncture surgery (CLP). Some diabetic rats were given neutral protamine Hagedorn (NPH) insulin (4 IU, s.c.) 2 h before CLP. Six h later, the lungs were examined for edema, cell infiltration and prostaglandin-E2 (PGE2) levels in the bronchoalveolar lavage (BAL). Results The results confirmed that leukocyte infiltration and edema were milder in diabetic rats with sepsis. After insulin treatment, the lung inflammation in diabetics increased to levels comparable to the non-diabetics. The BAL concentration of PGE2 was also lower in diabetics with sepsis, and increased after insulin treatment. Sepsis was followed by early fibroblast activation in the lung parenchyma, evaluated by increased transforming growth factor (TGF)-β and smooth muscle actin (α-SMA) expression, as well as an elevated number of cells with myofibroblasts morphology. These events were significantly lower in diabetic rats and increased after insulin treatment. Conclusion The results show that insulin modulates the early phase of inflammation and myofibroblast differentiation in diabetic rats.

The biosynthesis pathway of eicosanoids derived from arachidonic acid, such as prostaglandins and leukotrienes, relates to the pathophysiology of diabetes mellitus (DM). A better understanding of how lipid mediators modulate the inflammatory process may help recognize key factors underlying the progression of diabetes complications. Our review presents recent knowledge about eicosanoid synthesis and signaling in DM-related complications, and discusses eicosanoid-related target therapeutics.

Inflammation is a general tissue response to a wide variety of stimuli. In situations in which inflammation is not properly regulated, inflammatory response may be exaggerated or ineffective, leading to immune dysfunction, recurrent infections, and tissue damage, both locally and systemically. Various hormones, cytokines, vitamins, metabolites, and neurotransmitters are known to be key mediators of the immune and inflammatory responses in endocrine as well as in paracrine fashions. Therefore, exploring the mechanisms underlying the production and response to these mediators might broaden the horizons for the development of novel therapeutic options that target disease states in which the immune/inflammatory responses are compromised or dysregulated.

Acute lung injury (ALI) develops in response to a direct insult to the lung or secondarily to a systemic inflammatory response, such as sepsis. There is clinical evidence that the incidence and severity of ALI induced by direct insult are lower in diabetics. In the present study we investigated whether the same occurs in ALI secondarily to sepsis and the molecular mechanisms involved. Diabetes was induced in male Wistar rats by alloxan and sepsis by caecal ligation and puncture surgery (CLP). Six hours later, the lungs were examined for oedema and cell infiltration in bronchoalveolar lavage. Alveolar macrophages (AMs) were cultured in vitro for analysis of IκB and p65 subunit of NFκB phosphorylation and MyD88 and SOCS-1 mRNA. Diabetic rats were more susceptible to sepsis than non-diabetics. In non-diabetic rats, the lung presented oedema, leukocyte infiltration and increased COX2 expression. In diabetic rats these inflammatory events were significantly less intense. To understand why diabetic rats despite being more susceptible to sepsis develop milder ALI, we examined the NFκB activation in AMs of animals with sepsis. Whereas in non-diabetic rats the phosphorylation of IκB and p65 subunit occurred after 6 h of sepsis induction, this did not occur in diabetics. Moreover, in AMs from diabetic rats the expression of MyD88 mRNA was lower and that of SOCS-1 mRNA was increased compared with AMs from non-diabetic rats. These results show that ALI secondary to sepsis is milder in diabetic rats and this correlates with impaired activation of NFκB, increased SOCS-1 and decreased MyD88 mRNA.

AMs constitute an important bridge between innate and adaptive immunity. AMs patrol the lungs against pathogens, remove senescent cells, and help repair tissue. AM function is altered in many diseases, including DM, where AM abnormal immune responses may worsen infections or lead to exacerbation of inflammatory reactions. In vivo experimental models have greatly contributed to our knowledge of AM function. Studies have shown that during hyperglycemic states, the phagocytic function of AMs and the expression of adhesion molecules may be altered, interfering with the recruitment of immune cells to the inflammatory site. Insulin treatment seems to recover the normal function of impaired AMs. However, much research is still needed to characterize AMs and to better understand their role in inflammation and infection, particularly in diabetic patients. In this review, we attempt to explore recently accumulated knowledge about AM function and how this function is deficient in DM. Additionally, AM polarization is compared briefly with that of T cells, and this may interfere with how immune response is driven. This review discusses how impaired AMs lead to an aberrant immune response that contributes to worsening infection and autoimmunity, opening up discussion for future work in the field.

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundacao de Auxilio aos Docentes e Alunos-UNIFESP (FADA) Complex Fluids INCT Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The Th1/Th2 balance represents an important factor in the pathogenesis of renal ischemia-reperfusion injury (IRI). in addition, IRI causes a systemic inflammation that can affect other tissues, such as the lungs. To investigate the ability of renal IRI to modulate pulmonary function in a specific model of allergic inflammation, C57Bl/6 mice were immunized with ovalbumin/albumen on days 0 and 7 and challenged with an ovalbumin (OA) aerosol on days 14 and 21. After 24 h of the second antigen challenge, the animals were subjected to 45 minutes of ischemia. After 24 h of reperfusion, the bronchoalveolar lavage (BAL) fluid, blood and lung tissue were collected for analysis. Serum creatinine levels increased in both allergic and non-immunized animals subjected to IRI. However, BAL analysis showed a reduction in the total cells (46%) and neutrophils (58%) compared with control allergic animals not submitted to IRI. in addition, OA challenge induced the phosphorylation of ERK and Akt and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lung homogenates. After renal IRI, the phosphorylation of ERK and expression of COX-2 and iNOS were markedly reduced; however, there was no difference in the phosphorylation of Akt between sham and ischemic OA-challenged animals. Mucus production was also reduced in allergic mice after renal IRI. IL-4, IL-5 and IL-13 were markedly down-regulated in immunized/challenged mice subjected to IRI. These results suggest that renal IRI can modulate lung allergic inflammation, probably by altering the Th1/Th2 balance and, at least in part, by changing cellular signal transduction factors. Copyright (C) 2012 S. Karger AG, Basel Universidade Federal de São Paulo, Dept Ciencias Biol, Diadema, SP, Brazil Univ São Paulo, Fac Ciencias Farmaceut, Dept Anal Clin & Toxicol, São Paulo, Brazil Universidade Federal de São Paulo, Disciplina Nefrol, Lab Imunol Clin & Expt, São Paulo, Brazil Univ São Paulo, Inst Ciencias Biomed, Dept Imunol, BR-05508 São Paulo, Brazil Universidade Federal de São Paulo, Dept Ciencias Biol, Diadema, SP, Brazil Universidade Federal de São Paulo, Disciplina Nefrol, Lab Imunol Clin & Expt, São Paulo, Brazil FAPESP: 07/07139-3 FAPESP: 10/01404-0 Web of Science

Immunoendocrinology is an important field that studies the connection between the immune and endocrine systems. Hormones, including molecules like vitamin D and metabolic components, and neurotransmitters are compounds produced by different cell types that are capable of regulating the cross talk among cells from different tissues. During the last years, it became evident that hormones and neurotransmitters are specific modulators of cells of the immune system by fine-tuning their activation and key functions. This special issue covers the most recent research elucidating how hormones are able to regulate the recruitment of immune cells to an inflammatory site as well as to explain the hormonal impact on the intracellular signaling cascades that follow after tissue injury. It will cover the mechanisms by which hormones can influence inflammatory process. Diabetes mellitus is the most common cause of end-stage renal disease and chronic low-grade inflammation is an important factor in the pathogenesis of diabetic complication. Mycophenolate mofetil (MMF) has an anti-inflammatory effect, inhibiting lymphocyte proliferation. J.-W. Seo et al. study the effect of MMF on diabetic nephropathy and investigate its action mechanisms in type 2 diabetic mouse models. They demonstrated that MMF treatment attenuates diabetic nephropathy by decreasing CD4+ T cell infiltration and its related cytokines and chemokines. This anti-inflammatory effect of MMF attenuates podocyte apoptosis independent of glucose control. MicroRNAs are small noncoding RNA molecules that regulate gene expression in all cell types, which are involved in a wide range of biological processes, exerting functional effects at cell, tissue, and organ levels. G. Ventriglia et al. summarize the most recent data on the potential involvement of microRNAs in autoimmune diabetes and indicate that miRNAs represent major players in the dialogue between beta cells and immune system, regulating several aspects of their function and survival. Infection with the protozoan parasite Trypanosoma cruzi induces a hormonal systemic deregulation. A. F. Nardy et al. illustrated how the sphingosine-1-phosphate (S1P) system regulates both thymic and lymph node T cell egress which is essential for producing and maintaining the recycling T cell repertoire. The presence of this T cell receptor (TCR) bearing cells in the periphery may have potential implications for disease outcome. The authors discuss the possibility that the early egress of undifferentiated CD4−CD8− T cells plays a role in the immunopathologic events in Chagas disease by altering adaptive immune responses. The current evidence of the role of liver dendritic cells (DC) in the progression from nonalcoholic fatty liver disease (NAFLD) to fibrosis is reviewed by P. Almeda-Valdes et al. Link between lipid metabolism and DC function suggests that immunogenic DC are associated with liver lipid storage, which might represent a possible pathophysiological mechanism in NAFLD. Interactions between the pineal gland and the immune system have been studied ex vivo. A. P. Herman et al. provide evidence on how interleukin- (IL-) 1β suppresses melatonin secretion and its action seems to be targeted on the reduction of pineal gland arylalkylamine-N-acetyltransferase (AA-NAT) protein expression. Varicocele is the most common cause of infertility in men and the development of varicocele-related testis damage may be caused by disruption of homeostasis between cell proliferation and cell death. In addition, apoptosis is a physiological process by which a sequence of intracellular events results in the programmed elimination of a cell from its environment. Specifically, alterations in the apoptosis of germ cells may be crucial in varicocele-related human infertility and, as a direct consequence, targeting apoptosis may represent an alternative and rational therapeutic strategy in the treatment of varicocele complications. L. Minutoli et al. studied the effect of Polydeoxyribonucleotide (PDRN), an agonist of adenosine A2A receptor, on testicular Neuronal Apoptosis Inhibitory Protein (NAIP) and survivin expression in an experimental model of varicocele. They found that PDRN may represent a rational therapeutic option for accelerating recovery from depressed testicular function through a strategic modulation of apoptosis in experimental varicocele.

Insulin is a pivotal regulator of glucose metabolism and exerts an important anabolic function throughout the body. Insulin commands the glucose uptake by the cells and might control the processes in which there is need for energy such as mitogenesis and gene transcription. In certain conditions, diabetes mellitus for example, when insulin is diminished, the homeostasis of many tissues and organs are broken what can lead to a higher mortality due to an enhanced susceptibility to infections. This vulnerability to infections can partially be explained by a change in response to inflammation. In fact, diabetic animals and patients show a deficient inflammatory response. Many animal models have shown that neutrophils chemotaxis and recruitment are dampened and macrophages from diabetic patients have low phagocytic and microbicidal activities. In most cases, once insulin therapy is introduced, clinical symptoms and signs can be reverted. In addition, there are a number of studies trying to demystify pathways under insulin command. Researchers are also trying to understand how insulin is able to keep inflammatory response under control, restores innate immune cells ability to fight against pathogens and harmlessly activates adaptive immunity response. This review provides an overview on how inflammatory response is driven in the absence of insulin in diabetes and discusses recent findings on the influence of insulin on innate imune response. At the end, some signaling pathways are also highlighted and important enzymes and proteins that control DNA transcription are presented.

Objectives: Intraperitoneal administration of trypsin stimulates the production of cytokines from peritoneal macrophages. Removing the pancreatitis-associated ascitic fluid from the peritoneal cavity may decrease the systemic inflammatory response in acute pancreatitis (AP). We investigated the effect of peritoneal lavage on the systemic inflammatory response in severe AP. Methods: Acute pancreatitis was induced in Wistar rats by 5% taurocholate intraductal injection. Peritoneal lavage was performed for 4 hours after onset of AP. At 4 hours after induction of AP, serum samples were assayed for amylase and inflammatory cytokines (tumor necrosis factor >, interleukin-6 [IL-6], and IL-10). Expression of pancreatic cyclooxygenase-2 and inducible nitric oxide synthase, liver mitochondrial function, and pulmonary myeloperoxidase activities were determined. Results: Peritoneal lavage after AP led to a decrease in serum levels of tumor necrosis factor > and IL-6 and an increase in IL-10. In the pancreas, this treatment reduced cyclooxygenase-2 and inducible nitric oxide synthase expression. Liver mitochondrial dysfunction was also reduced. There were no differences on serum amylase levels and pulmonary myeloperoxidase between groups with AP. Conclusions: Peritoneal lavage has a systemic anti-inflammatory effect in severe AP and may be able to decrease the severity of severe AP.

Ischemia and reperfusion injury (IRI) are mainly caused by leukocyte activation, endothelial dysfunction and production of reactive oxygen species. Moreover, IRI can lead to a systemic response affecting distant organs, such as the lungs.The objective was to study the pulmonary inflammatory systemic response after renal IRI.Male C57Bl/6 mice were subjected to 45 min of bilateral renal ischemia, followed by 4, 6, 12, 24 and 48 h of reperfusion. Blood was collected to measure serum creatinine and cytokine concentrations. Bronchoalveolar lavage fluid (BALF) was collected to determine the number of cells and PGE(2) concentration. Expressions of iNOS and COX-2 in lung were determined by Western blot. Gene analyses were quantified by real time PCR.Serum creatinine increased in the IRI group compared to sham mainly at 24 h after IRI (2.57 +/- 0.16 vs. 0.43 +/- 0.07, p0.01). The total number of cells in BAL fluid was higher in the IRI group in comparison with sham, 12 h (100 x 10(4) +/- 15.63 vs. 18.1 x 10(4) +/- 10.5, p0.05) 24 h (124 x 10(4) +/- 8.94 vs. 23.2 x 10(4) +/- 3.5, p0.05) and 48 h (79 x 10(4) +/- 15.72 vs. 22.2 x 10(4) +/- 4.2, p0.05), mainly by mononuclear cells and neutrophils. Pulmonary COX-2 and iNOS were up-regulated in the IRI group. TNF-alpha, IL-1beta, MCP-1, KC and IL-6 mRNA expression were up-regulated in kidney and lungs 24 h after renal IRI. ICAM-1 mRNA was up-regulated in lungs 24 h after renal IRI. Serum TNF-alpha, IL-1beta and MCP-1 and BALF PGE(2) concentrations were increased 24 h after renal IRI.Renal IRI induces an increase of cellular infiltration, up-regulation of COX-2, iNOS and ICAM-1, enhanced chemokine expression and a Th1 cytokine profile in lung demonstrating that the inflammatory response is indeed systemic, possibly leading to an amplification of renal injury.

Neutrophils act as first-line-of-defense cells and the reduction of theirfunctional activity contributes to the high susceptibility to and severityof infections in diabetes mellitus. Clinical investigations in diabeticpatients and experimental studies in diabetic rats and mice clearlydemonstrated consistent defects of neutrophil chemotactic, phagocyt-ic and microbicidal activities. Other alterations that have been re-ported to occur during inflammation in diabetes mellitus include:decreased microvascular responses to inflammatory mediators such ashistamine and bradykinin, reduced protein leakage and edema forma-tion, reduced mast cell degranulation, impairment of neutrophil adhe-sion to the endothelium and migration to the site of inflammation,production of reactive oxygen species and reduced release of cyto-kines and prostaglandin by neutrophils, increased leukocyte apopto-sis, and reduction in lymph node retention capacity. Since neutrophilfunction requires energy, metabolic changes (i.e., glycolytic andglutaminolytic pathways) may be involved in the reduction of neutro-phil function observed in diabetic states. Metabolic routes by whichhyperglycemia is linked to neutrophil dysfunction include the ad-vanced protein glycosylation reaction, the polyol pathway, oxygen-free radical formation, the nitric oxide-cyclic guanosine-3'-5’mono-phosphate pathway, and the glycolytic and glutaminolytic pathways.Lowering of blood glucose levels by insulin treatment of diabeticpatients or experimental animals has been reported to have significantcorrelation with improvement of neutrophil functional activity. There-fore, changes might be primarily linked to a continuing insulindeficiency or to secondary hyperglycemia occurring in the diabeticindividual. Accordingly, effective control with insulin treatment islikely to be relevant during infection in diabetic patients.

The present study was undertaken to investigate the influence of insulin on lipopolysaccharide (LPS)-induced acute lung injury. Diabetic male Wistar rats (alloxan, 42 mg/kg, i.v., 30 days) and controls were instilled with saline containing LPS (750 microg/0.4 mL) or saline alone. The following analyses were performed 6 h there after: (a) total and differential cell counts in bronchoalveolar lavage (BAL) fluid, (b) quantification of tumor necrosis factor alpha, interleukin (IL) 1beta, IL-10, and cytokine-induced neutrophil chemoattractant 1 in the BAL (enzyme-linked immunosorbent assay), (c)immunohistochemistry for intercellular adhesion molecule 1 and E-selectin on lung vessels, and (d) quantification of metalloproteinases (MMP) 2 and 9 in the BAL (zymography). Relative to controls, diabetic rats exhibited a reduction in the number of neutrophils (80%) and reduced concentrations of tumor necrosis factor alpha (56%), IL-1beta (66%), and IL-10 (35%) after LPS instillation. Cytokine-induced neutrophil chemoattractant 1 levels did not differ between groups. Increased levels of MMP-2 (90%) and MMP-9 (500%) were observed in diabetic rats compared with controls. Treatment of diabetic rats with neutral protamine Hagedorn insulin (4 IU, s.c.), 2 h before LPS instillation, completely restored the number of neutrophils and concentrations of cytokines in the BAL fluid. Despite no significant differences between diabetic and control groups, there was a remarkable increase in intercellular adhesion molecule 1 and E-selectin expression on lung vessels after insulin treatment. Levels of MMP-2 and MMP-9 did not change after treatment with insulin. Levels of corticosterone were equivalent among groups. Data presented suggest that insulin modulates the production/release of cytokines and the expression of adhesion molecules controlling, therefore, neutrophil migration during the course of LPS-induced acute lung inflammation.