Insulin regulates cytokines and intercellular adhesion molecule-1 gene expression through nuclear factor-kappaB activation in LPS-induced acute lung injury in rats

A 'one stone, two birds' approach with mesenchymal stem cells for acute respiratory distress syndrome and Type II diabetes mellitus

This review explores the intricate relationship between acute respiratory distress syndrome (ARDS) and Type II diabetes mellitus (T2DM). It covers ARDS epidemiology, etiology and pathophysiology, along with current treatment trends and challenges. The lipopolysaccharides (LPS) role in ARDS and its association between non-communicable diseases and COVID-19 are discussed. The review highlights the therapeutic potential of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) for ARDS and T2DM, emphasizing their immunomodulatory effects. This review also underlines how T2DM exacerbates ARDS pathophysiology and discusses the potential of hUC-MSCs in modulating immune responses. In conclusion, the review highlights the multidisciplinary approach to managing ARDS and T2DM, focusing on inflammation, oxidative stress and potential therapy of hUC-MSCs in the future.

Combination Therapy of Niacin and Apocynin Attenuates Lung Injury During Sepsis in Rats

INTRODUCTION

Oxidative stress contributes to tissue injury through reactive oxygen species-dependent signaling pathways during sepsis. We studied therapeutic benefits of the combination therapy of niacin, which increased reduced glutathione levels, and apocynin, which suppressed reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) activity, in septic rats.

MATERIALS AND METHODS

Polymicrobial sepsis was induced through cecal ligation and puncture (CLP) with antibiotics in male Sprague-Dawley rats (n = 189). The rats were randomly divided into sham, CLP, CLP + niacin, CLP + apocynin, and CLP + niacin + apocynin groups. Six hours after CLP, vehicle, niacin (360 mg/kg through the orogastric tube), and/or apocynin (20 mg/kg through intraperitoneal injection) were administered. The occurrence of mortality for 72 h after CLP was observed. Next, a separate set of animals was euthanized at 24 h post-CLP for lung tissue analyses.

RESULTS

Combination therapy with niacin and apocynin significantly improved survival in rats with sepsis (75.0% versus 28.8%, P = 0.006) but monotherapy with niacin or apocynin did not. Monotherapy with niacin and apocynin appeared to increase NADPH levels and decrease Nox levels and activity, respectively, but failed to show statistical significances. However, combination therapy significantly decreased Nox levels and activity, increased NADPH and glutathione levels, decreased intranuclear nuclear factor-κB (NF-κB) p65 levels, reduced inflammatory cytokine expression and malondialdehyde levels, and attenuated histological lung injuries.

CONCLUSIONS

Combination therapy with niacin and apocynin synergistically attenuated lung injuries and improved survival in rats with sepsis through niacin-induced glutathione redox cycle activation and apocynin-induced Nox suppression.

Prediction of acute lung injury in severe acute pancreatitis by routine clinical data

AIM

Acute lung injury (ALI) is a common complication of severe acute pancreatitis (SAP) with a high mortality. Early prediction of patients at risk in initial stage can improve the long-term survival.

METHODS

A total of 91 patients with SAP out of 1647 acute pancreatitis patients from January 2015 to December 2020 were considered. A predictive model for SAP-associated ALI was constructed based on the valuable risk factors identified from routine clinical characteristics and plasma biomarkers. The value of the model was evaluated and compared with Lung Injury Prediction Score (LIPS). A nomogram was built to visualize the model.

RESULTS

Diabetes, oxygen supplementation, neutrophil count and D-dimer were found to be associated with ALI in SAP. The predictive model based on these factors had an area under the receiver operating characteristic curve [AUC: 0.88, 95% confidence interval (CI): 0.81-0.95], which was superior to LIPS (AUC: 0.71, 95% CI: 0.60-0.83), also with the higher sensitivity (65%) and specificity (96%) than LIPS (62%, 74%, respectively). Decision curve analysis of the model showed a higher net benefit than LIPS. Visualization by a nomogram facilitated the application of the model.

CONCLUSION

Diabetes, oxygen supplementation, neutrophil count and D-dimer were risk factors for SAP-associated ALI. The combination of these routine clinical data and the model visualization by a nomogram provided a simple and effective way in predicting ALI in the early phase of SAP.

Correlation of Impaired NF-kB Activation in Sepsis-Induced Acute Lung Injury (ALI) in Diabetic Rats

Background

The allergic lung inflammation is reduced in the diabetic rats which can be restored by treating it with insulin. As observed in multiple studies, the diabetic patients are more vulnerable to infections and their inflammatory reactions. There are confirmations on insulin and its effects control the inflammatory reactions.

Objective

This study was performed to understand the correlation of impaired NF-kB activation in sepsis-induced acute lung injury (ALI) in diabetic rats. Material and Methods. Streptozotocin was used for induction of diabetes and sepsis was induced by colon ligation puncture surgery. Post 6 hours of CLP, the lungs in the groups were analyzed for cell infiltration using broncho-alveolar lavage. The lungs were removed for histopathological analysis at the end of study where the bronchioles, alveoli, and edema were analyzed and compared. Cell expressions quantified by the help of antibodies and inflammatory events were analyzed.

Results

Diabetic rats developed mild acute lung injury due to the suppression of activation of NF-kB in alveolar macrophages.

Conclusion

Even the diabetic rats were more susceptible to sepsis in comparison to the nondiabetic rats, but the NF-kB suppression has a major role to play in the faint symptoms of ALI.

Angiotensin-Converting Enzyme 2 (ACE2) as a Potential Diagnostic and Prognostic Biomarker for Chronic Inflammatory Lung Diseases

Chronic inflammatory lung diseases are characterized by uncontrolled immune response in the airways as their main pathophysiological manifestation. The lack of specific diagnostic and therapeutic biomarkers for many pulmonary diseases represents a major challenge for pulmonologists. The majority of the currently approved therapeutic approaches are focused on achieving disease remission, although there is no guarantee of complete recovery. It is known that angiotensin-converting enzyme 2 (ACE2), an important counter-regulatory component of the renin–angiotensin–aldosterone system (RAAS), is expressed in the airways. It has been shown that ACE2 plays a role in systemic regulation of the cardiovascular and renal systems, lungs and liver by acting on blood pressure, electrolyte balance control mechanisms and inflammation. Its protective role in the lungs has also been presented, but the exact pathophysiological mechanism of action is still elusive. The aim of this study is to review and discuss recent findings about ACE2, including its potential role in the pathophysiology of chronic inflammatory lung diseases:, i.e., chronic obstructive pulmonary disease, asthma, and pulmonary hypertension. Additionally, in the light of the coronavirus 2019 disease (COVID-19), we will discuss the role of ACE2 in the pathophysiology of this disease, mainly represented by different grades of pulmonary problems. We believe that these insights will open up new perspectives for the future use of ACE2 as a potential biomarker for early diagnosis and monitoring of chronic inflammatory lung diseases.

Role of Renin-Angiotensin System in Acute Lung Injury Caused by Viral Infection

The renin-angiotensin system (RAS) is the most important regulatory system of electrolyte homeostasis and blood pressure and acts through angiotensin-converting enzyme (ACE)/angiotensin II (Ang II)/Ang II type 1 (AT1) receptor axis and angiotensin-converting enzyme 2 (ACE2)/angiotensin (1-7)/MAS receptor axis. RAS dysfunction is related to the occurrence and development of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) and causes a serious prognosis and even death. ALI/ARDS can be induced by various ways, one of which is viral infections, such as SARS-CoV, SARS-CoV-2, H5N1, H7N9, and EV71. This article reviews the specific mechanism on how RAS dysfunction affects ALI/ARDs caused by viral infections. SARS-CoV and SARS-CoV-2 enter the host cells by binding with ACE2. H5N1 and H7N9 avian influenza viruses reduce the ACE2 level in the body, and EV71 increases Ang II concentration. Treatment with angiotensin-converting enzyme inhibitor and angiotensin AT1 receptor blocker can alleviate ALI/ARDS symptoms. This review provides suggestions for the treatment of lung injury caused by viral infections.

Cytokine and Adhesion Molecule Expression Induced by Different Strains of Staphylococcus aureus in Type 1 Diabetic Rats: Role of Insulin

Introduction: Staphylococcus aureus may provoke peritonitis and death, especially in immunocompromized individuals such as diabetic patients. We evaluated the role of insulin in S. aureus-induced peritoneal infection in diabetic and non-diabetic rats. Materials/Methods: Alloxan-diabetic male Wistar rats and their respective controls received intraperitoneal injections of different strains of S. aureus or sterile phosphate-buffered saline. After 3 days of infection, the first set of diabetic and non-diabetic rats received 4 and 1 IU, respectively, of neutral protamine Hagedorn insulin and were analyzed 8 h later. The second set of diabetic and non-diabetic rats received 4 and 1 IU, respectively, of insulin 2 h before intraperitoneal infection and a half dose of insulin at 5 p.m. for the next 2 days and were analyzed 16 h later. The following measurements were performed: (a) number of cells in the peritoneal lavage fluid (PeLF), white blood cell count, and blood glucose; (b) serum insulin and corticosterone; (c) cytokine levels in the PeLF; (d) expression of adhesion molecules in the vascular endothelium; and (e) microbicidal activity. Results: Diabetic rats showed an increased number of polymorphonuclear leukocytes (PMNs) and increased concentrations of CINC-1, IL-4, and IFN-γ in the PeLF after infection with the ATCC 25923 or N315 αHL⁺ strain. The mesenteric expression of PECAM-1 was increased after infection with the N315 HLA⁺ strain. ICAM-1 expression was increased with ATCC infection. Treatment of diabetic rats with a single dose of insulin restored CINC-1 levels in the PeLF for both strains; however, PMN migration, IL-4, and IFN-γ were restored in rats infected with the ATCC strain, whereas the PeLF concentrations of CINC-2, IL-1β, and IL-4 were increased in N315-infected animals. Insulin restored PMN migration and CINC-2 levels in the PeLF in ATCC-infected rats. After multiple treatments with insulin, the levels of IL-1β, IL-6, and IFN-γ were increased in the PeLF of diabetic rats after infection with either strain, and CINC-2 levels were restored in N315-infected animals. Conclusion: These results suggest that insulin distinctively modulates cytokine production or release, PMN leukocyte migration, and adhesion molecule expression during the course of peritonitis induced by different strains of S. aureus.

Niacin and Selenium Attenuate Sepsis-Induced Lung Injury by Up-Regulating Nuclear Factor Erythroid 2-Related Factor 2 Signaling

OBJECTIVES

To determine whether the combination therapy of niacin and selenium attenuates lung injury and improves survival during sepsis in rats and whether its benefits are associated with the activation of the glutathione redox cycle and up-regulation of nuclear factor erythroid 2-related factor 2.

DESIGN

Prospective laboratory study.

SETTING

University laboratory.

SUBJECTS

Human lung microvascular endothelial cells and male Sprague-Dawley rats (n = 291).

INTERVENTION

In lipopolysaccharide-exposed cells, the dose-related effects of niacin and selenium were assessed, and the therapeutic effects of the combination therapy of niacin (0.9 mM) and selenium (1.5 μM) were evaluated. The role of nuclear factor erythroid 2-related factor 2 was determined using nuclear factor erythroid 2-related factor 2 knockdown cells. In endotoxemic and cecal ligation and puncture with antibiotics rats, the therapeutic effects of the posttreatments of clinically relevant doses of niacin (360 mg/kg) and selenium (60 μg/kg) were evaluated.

MEASUREMENTS AND MAIN RESULTS

Combination therapy reduced the hydrogen peroxide level via the synergistic activation of the glutathione redox cycle, which involves niacin-induced increases in glutathione reductase activity, and reduced the glutathione level and a selenium-induced increase in glutathione peroxidase activity. Combination therapy contributed to the up-regulation of nuclear factor erythroid 2-related factor 2, enhancement of glutathione synthesis, and down-regulation of nuclear factor κB signaling, but nuclear factor erythroid 2-related factor 2 knockdown inhibited the enhancement of glutathione synthesis and down-regulation of the nuclear factor κB pathway. The therapeutic effects of combination therapy on endotoxemic rats were consistent with those on lipopolysaccharide-exposed cells. In addition, the posttreatment of combination therapy attenuated lung injury and improved survival in endotoxemic and cecal ligation and puncture with antibiotics rats. However, individual therapies of niacin or selenium failed to achieve these benefits.

CONCLUSIONS

The combination therapy of niacin and selenium attenuated lung injury and improved survival during sepsis. Its therapeutic benefits were associated with the synergistic activation of the glutathione redox cycle, reduction of hydrogen peroxide level, and up-regulation of nuclear factor erythroid 2-related factor 2.

Basal insulin therapy is associated with beneficial effects on postoperative infective complications, independently from circulating glucose levels in patients admitted for cardiac surgery

•

The effect of insulin per se on infective complications during cardiac surgery was evaluated.

•

Eight hundred twelve patients were included.

•

Insulin therapy decreased infections independently from glycemic levels.

•

Basal + premeal insulin therapy is well tolerated without severe hypoglycemia cases.

Background

Although hyperglycemia is a strong predictor of postoperative infective complications (PIC), little is known about the effect of basal insulin therapy (BIT) per se on PIC.

Aim

To evaluate if there is an association between BIT, independent of glucose levels, and a possible improvement of PIC during the perioperative cardiosurgery period (PCP).

Methods

In 812 patients admitted for cardiac intervention and treated with a continuous intravenous insulin infusion (CIII) for hyperglycemic levels (>130 mg/dl), a retrospective analysis was performed during the PCP (January 2009–December 2011). Upon transfer to the cardiac surgery division, if fasting glucose was ≥130 mg/dl, a basal + premeal insulin therapy was initiated (121 patients, group 1); for <130 mg/dl, a premeal insulin alone was initiated (691 patients, group 2).

Findings

Compared with group 2, group 1 showed reductions in PIC (2.48% vs 7.96%, p < 0.049; odds ratio: 0.294; 95% CI: 0.110–0.780), C-Reactive Protein (p < 0.05) and white blood cell (p < 0.05) levels despite glucose levels and CIII that were higher during the first two days after surgery (179.8 ± 25.3 vs 169.5 ± 10.6 mg/dl, p < 0.01; 0.046 ± 0.008 vs 0.037 ± 0.015 U/kg/h, p < 0.05, respectively). Normal glucose levels were achieved in both groups from day 3 before the discharge. The mean length of hospital duration was 18% lower in group 1 than in group 2 (7.21 ± 05.08 vs 8.76 ± 9.08 days, p < 0.007), providing a significant impact on public health costs.

Conclusions

Basal + preprandial insulin therapy was associated with a lower frequency of PIC than preprandial insulin therapy alone, suggesting a beneficial effect of basal insulin therapy on post-surgery outcome.

Amphiregulin suppresses epithelial cell apoptosis in lipopolysaccharide-induced lung injury in mice

BACKGROUND AND OBJECTIVE

As a member of the epidermal growth factor family, amphiregulin contributes to the regulation of cell proliferation. Amphiregulin was reported to be upregulated in damaged lung tissues in patients with chronic obstructive pulmonary disease and asthma and in lung epithelial cells in a ventilator-associated lung injury model. In this study, we investigated the effect of amphiregulin on lipopolysaccharide (LPS)-induced acute lung injury in mice.

METHODS

Acute lung injury was induced by intranasal instillation of LPS in female C57BL/6 mice, and the mice were given intraperitoneal injections of recombinant amphiregulin or phosphate-buffered saline 6 and 0.5 h before and 3 h after LPS instillation. The effect of amphiregulin on apoptosis and apoptotic pathways in a murine lung alveolar type II epithelial cell line (LA-4 cells) were examined using flow cytometry and western blotting, respectively.

RESULTS

Recombinant amphiregulin suppressed epithelial cell apoptosis in LPS-induced lung injury in mice. Western blotting revealed that amphiregulin suppressed epithelial cell apoptosis by inhibiting caspase-8 activity.

CONCLUSION

Amphiregulin signaling may be a therapeutic target for LPS-induced lung injury treatment through its prevention of epithelial cell apoptosis.

Selenium Deficiency Attenuates Chicken Duodenal Mucosal Immunity via Activation of the NF-κb Signaling Pathway

Selenium (Se) deficiency can cause intestinal mucosal inflammation, which is related to activation of nuclear transcription factor kappa-B (NF-κB) signaling pathway. However, the mechanism of inflammatory response in chicken duodenal mucosa caused by Se deficiency and its relationship with the NF-κB signaling pathway remain elusive. In this study, we firstly obtained Se-deficient chickens bred with 0.01 mg/kg Se and the normal chickens bred with 0.4 mg/kg Se for 35 days. Then, NF-κB signaling pathway, secretory immunoglobulin A (SIgA), inflammatory cytokines, oxidized glutathione, glutathione peroxidase, and glutathione activities were determined. The results showed that Se deficiency obviously enhanced p50, p65, and p65 DNA-binding activities. The phosphorylation of IκB-α and phosphorylation of kappa-B kinase subunit alpha (IKKα) and IKKα were elevated, but IκB-α was decreased (P < 0.05). Moreover, Se deficiency reduced SIgA amount in the duodenal mucosa but increased the level of interleukin-1β (IL-1β), IL-17A, tumor necrosis factor-α (TNF-α), and interferon gamma (IFN-γ). In contrast, anti-inflammatory cytokines, such as TGF-β1 and IL-10, were significantly suppressed. Additionally, Se deficiency increased oxidized glutathione activity, whereas decreased glutathione peroxidase and glutathione activities (P < 0.05), suggesting that Se deficiency affected the regulation function of redox. Taken together, our results demonstrated that Se deficiency attenuated chicken duodenal mucosal immunity via activation of NF-κB signaling pathway regulated by redox activity, which suggested that Se is a crucial host factor involved in regulating inflammation.

Antioxidant and anti-inflammatory effects of selenium in oral buccal mucosa and small intestinal mucosa during intestinal ischemia-reperfusion injury

Background

The aim of this study were to investigate whether selenium treatment attenuates lipid peroxidation and downregulates the NF-κB pathway in small intestinal mucosa and to examine whether the effect of selenium is also observed in oral buccal mucosa, during small intestinal IR injury.

Materials and methods

Eighteen rats were assigned into three groups: sham, IR, and IR + selenium. Saline or selenium was administered through a tail vein. 24 hours later, the superior mesenteric artery was exposed and clamped in the IR and IR + selenium groups. After ischemic and reperfusion period, animals were sacrificed and oral buccal mucosa and small intestinal mucosa were harvested.

Results

Glutathione peroxidase activity and cytoplasmic IκB-α expression was higher in the IR + selenium group than that in the IR group. A malondialdehyde level, cytoplasmic phosphorylated inhibitor κB-α, nuclear NF-κB p65 expressions, and NF-κB p65 DNA-binding activity were lower in the IR + selenium group than those in the IR group.

Conclusion

A selenium treatment may cause increased GPx activity, attenuated lipid peroxidation, and downregulated the NF-κB pathway during small intestinal IR injury. Furthermore, these therapeutic benefits of selenium can be observed in oral buccal mucosa as well as small intestinal mucosa.

Deregulation of inflammatory response in the diabetic condition is associated with increased ischemic brain injury

Background

Although elicited inflammation contributes to tissue injury, a certain level of inflammation is necessary for subsequent tissue repair/remodeling. Diabetes, a chronic low-grade inflammatory state, is a predisposing risk factor for stroke. The condition is associated with delayed wound healing, presumably due to disrupted inflammatory responses. With inclusion of the diabetic condition in an experimental animal model of stroke, this study investigates whether the condition alters inflammatory response and influences stroke-induced brain injury.

Methods

C57BL/6 mice were fed a diabetic diet (DD) for 8 weeks to induce an experimental diabetic condition or a normal diet (ND) for the same duration. Gene expression of inflammatory factors including monocyte chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6), CCR2, and CD36 was assessed in the peripheral immune cells and brains of normal and diabetic mice before and after focal cerebral ischemia. The expression of these factors was also determined in lipopolysaccharide (LPS)-treated cultured normal and diabetic macrophages. Ischemic outcome was assessed in these mice at 3 days post-ischemia.

Results

DD intervention in mice resulted in obesity and elevated insulin and glucose level in the blood. The peritoneal immune cells from the diabetic mice showed higher MCP-1 mRNA levels before and after stroke. Compared to normal mice, diabetic mice showed reduced MCP-1, IL-6, and CCR2 gene expression in the brain at 6 h post-ischemia. LPS-stimulated inflammatory responses were also reduced in the diabetic macrophages. The diabetic mice showed larger infarct size and percent swelling.

Conclusions

These results showed that diabetic conditions deregulate acute inflammatory response and that the condition is associated with increased stroke-induced injury. The study suggests that interventions aimed at restoring appropriate inflammatory response in peripheral immune cells/macrophages may be beneficial in reducing stroke-induced brain injury in subjects with chronic inflammatory conditions.

Interleukin (IL)-4 induces production of cytokine-induced neutrophil chemoattractants (CINCs) and intercellular adhesion molecule (ICAM)-1 in lungs of asthmatic rats

The present study aimed to examine the effect of interleukin (IL)-4 on neutrophil chemotaxis in airway inflammation in asthmatic rats and the possible mechanism. Male Wistar rats were intranasally instilled with recombinant rat (rr) IL-4 (rrIL-4) at different doses [2, 4 or 8 μg/animal, dissolved in 200 μL normal saline (NS)] or rrIL-4 at 4 μg/animal (dissolved in 200 μL NS). NS (200 μL) and LPS (6 mg/kg/animal, dissolved in 200 μL NS) were intranasally given respectively in the negative and positive control groups. Moreover, the asthmatic lung inflammation was induced in rats which were then intranasally treated with rrIL-4 (4 μg/animal) or LPS (6 mg/kg/animal). The normal rats treated with different doses of rrIL-4 and those asthmatic rats were sacrificed 6 h later. And animals instilled with rrIL-4 at 4 μg were sacrificed 6, 12 or 24 h later. The bronchoalveolar lavage fluid (BALF) and lungs were harvested for detection of leukocyte counts by Wright-Giemsa staining and lung histopathology by haematoxylin-eosin (HE) staining. The levels of cytokine-induced neutrophil chemoattractant (CINC)-1 and intercellular adhesion molecule (ICAM)-1 in BALF were determined by ELISA. Real-time PCR was used to measure the mRNA expression of CINCs (CINC-1, CINC-2α, CINC-2β, CINC-3) and ICAM-1 in lung tissues. The results showed that the intranasal instillation of IL-4 did not induce a recruitment of neutrophils in BALF in rats. However, IL-4 could increase the CINC-1 level in BALF in a dose-dependent manner at 6 h. But the mRNA expression levels of CINC-1, CINC-2α, CINC-2β, CINC-3 were not significantly increased in lungs of IL-4-treated rats relative to NS negative control group. Moreover, IL-4 was found to augment the mRNA expression of ICAM-1 in lungs and the ICAM-1 level in BALF at 6 h. However, the increase in CINC-1 and ICAM-1 levels in BALF of IL-4-treated asthmatic rats was not significantly different from that in untreated asthmatic rats. These findings indicate that IL-4 does not directly recruit neutrophils in the rat lungs, but it may contribute to airway neutrophilia through up-regulation of CINC-1 and ICAM-1.

NF-κB pathway activators as potential ageing biomarkers: targets for new therapeutic strategies

Chronic inflammation is a major biological mechanism underpinning biological ageing process and age-related diseases. Inflammation is also the key response of host defense against pathogens and tissue injury. Current opinion sustains that during evolution the host defense and ageing process have become linked together. Thus, the large array of defense factors and mechanisms linked to the NF-κB system seem to be involved in ageing process. This concept leads us in proposing inductors of NF-κB signaling pathway as potential ageing biomarkers. On the other hand, ageing biomarkers, represented by biological indicators and selected through apposite criteria, should help to characterize biological age and, since age is a major risk factor in many degenerative diseases, could be subsequently used to identify individuals at high risk of developing age-associated diseases or disabilities. In this report, some inflammatory biomarkers will be discussed for a better understanding of the concept of biological ageing, providing ideas on eventual working hypothesis about potential targets for the development of new therapeutic strategies and improving, as consequence, the quality of life of elderly population.

Inosine monophosphate dehydrogenase expression and activity are significantly lower in kidney transplant recipients with diabetes mellitus

BACKGROUND

Inosine 5'-monophosphate dehydrogenase (IMPDH) is a target of the immunosuppressive drug, mycophenolic acid (MPA). A 12-hour clinical pharmacokinetic and pharmacodynamic study was conducted to compare IMPDH1 and IMPDH2 gene expression, IMPDHI and IMPDHII protein levels, and enzyme activity between kidney transplant recipients with respect to diabetes status.

METHODS

Nondiabetic (ND, n = 11) and diabetic (D, n = 9) kidney transplant recipients and on nontransplant nondiabetic (n = 10) and diabetic (n = 10) volunteers were included in the study.

RESULTS

Area under the effect curve values for gene expression: IMPDH1 [ND: 22.1 (13.8-31.3) versus D: 4.5 (2.3-6.5), P < 0.001] and IMPDH2 [ND: 15.3 (11.0-21.7) versus D: 6.1 (4.6-8.6), P < 0.001], protein level: IMPDHI [ND: 1.0 (0.5-1.3) versus 0.5 (0.4-0.7), P = 0.002] and IMPDHII [ND: 1.0 (0.6-1.6) versus D: 0.7 (0.6-0.8) P < 0.001] and enzyme activity [ND: 180 (105-245) versus D: 29.9 (15.3-35.6) µmole·s(-1)·mole(-1) adenosine monophosphate, P < 0.001] was significantly lower in transplant recipients with diabetes. Similar results were observed in nontransplanted volunteers. Kinetic studies of MPA-mediated suppression of IMPDH activity in nontransplanted individuals revealed an approximately 2.5-fold lower half-maximum effective concentration (EC50) for diabetic as compared with nondiabetic [ND: 50.2 (49.8-50.7) versus D: 15.8 (15.6-16.3) nmole/L, P = 0.004] volunteers. This difference was not related to several IMPDH gene variants.

CONCLUSIONS

This study indicates a significantly lower IMPDH gene expression, protein level, and enzyme activity in diabetic patients. Further clinical studies in a larger number of patients are warranted to verify whether MPA dosing must be optimized for kidney transplant recipients with diabetes mellitus.

Immunomodulatory effects of black seeds and garlic on alloxan-induced Diabetes in albino rat

BACKGROUND

Alteration in the proliferation capacity of leukocytes and in the level of some cytokines, such as TNF-α, IL-4 and IL-8 have been suggested to associate with Diabetes mellitus in alloxan-induced diabetic rats given the potential immunomodulatory effects of black seeds and garlic.

AIM OF THE WORK

The aim of this study was to test the effects of these agents on the immune cells in alloxan-induced diabetic rats.

METHODS

To this end, Diabetes was induced in albino rats by a single intraperitoneal injection of alloxan monohydrate (120mg/kg of body weight). Diabetic rats were then fed normal diet or diet with black seeds or garlic for 28 days.

RESULTS

The results showed significant increase in the numbers of monocytes and granulocytes, but with significant decreases in lymphocyte proliferation and the TNF-α, interleukin (IL)-4 and IL-8 levels in the diabetic group. Treatment of diabetic rats with black seeds or garlic induced significant amelioration in the numbers of monocytes and granulocytes, with significant increase in lymphocytes numbers and the TNF-α, IL-4 and IL-8 levels.

CONCLUSIONS

These results indicate the potential beneficial effects of black seeds and garlic as adjuvant treatment during treatment of Diabetes.

Expressions of nuclear factor-kappa B p50 and p65 and their significance in the up-regulation of intercellular cell adhesion molecule-1 mRNA in the nasal mucosa of allergic rhinitis patients

The purpose of the study was to investigate expressions of nuclear factor-kappa B (NF-κB) and intercellular cell adhesion molecule-1 mRNA (ICAM-1 mRNA) in the nasal mucosa of allergic rhinitis (AR) patients. Expressions of NF-κB and ICAM-1 mRNA were studied using immunohistochemistry and reverse transcription-PCR (RT-PCR) in AR tissues and corresponding normal nasal mucosa. The correlation between NF-κB and ICAM-1 mRNA was studied using linear correlation analysis. The results of immunohistochemistry showed that expression of NF-κB was significantly up-regulated in the nasal mucosa of AR compared with that in normal tissue (P < 0.01), over-expression of NF-κB p50 was found in the cytoplasm and nucleus (P < 0.01), and NF-κB p65 was mainly expressed in the cytoplasm (P < 0.01). ICAM-1 mRNA was strongly expressed in the nasal mucosa of AR compared with that in normal tissue as shown by RT-PCR (P < 0.01). Up-regulation of ICAM-1 mRNA was significantly correlated with over-expressions of NF-κB p50 and NF-κB p65 (r = 0.8995, P < 0.01; r = 0.7601, P < 0.01). In conclusion, NF-κB plays a key role in AR. Excessively activated NF-κB promotes the transcription of ICAM-1 mRNA. ICAM-1 is related to the pathogenesis and development of AR.

Insulin modulates the inflammatory granulocyte response to streptococci via phosphatidylinositol 3-kinase

Group B streptococci (GBS; Streptococcus agalactiae) are a major cause of invasive infections in newborn infants and in patients with type 2 diabetes. Both patient groups exhibit peripheral insulin resistance and alterations in polymorphonuclear leukocyte (PML) function. In this investigation, we studied the PML response repertoire to GBS with a focus on TLR signaling and the modulation of this response by insulin in mice and humans. We found that GBS-induced, MyD88-dependent chemokine formation of PML was specifically downmodulated by insulin via insulin receptor-mediated induction of PI3K. PI3K inhibited transcription of chemokine genes on the level of NF-κB activation and binding. Insulin specifically modulated the chemokine response of PML to whole bacteria, but affected neither activation by purified TLR agonists nor antimicrobial properties, such as migration, phagocytosis, bacterial killing, and formation of reactive oxygen species. The targeted modulation of bacteria-induced chemokine formation by insulin via PI3K may form a basis for the development of novel targets of adjunctive sepsis therapy.

Insulin modulates inflammatory and repair responses to elastase-induced emphysema in diabetic rats

As pulmonary emphysema and diabetes mellitus are common diseases, concomitance of both is correspondingly expected to occur frequently. To examine whether insulin influences the development of inflammation in the alveolar septa, diabetic male Wistar rats (alloxan, 42 mg/kg, i.v., n = 37) and matching controls (n = 31) were used. Ten days after alloxan injection, diabetic and control rats were instilled with physiologic saline solution containing porcine pancreatic elastase (PPE, 0.25 IU/0.2 ml, right lung) or saline only (left lung). The following analyses were performed: (i) number of leucocytes in the bronchoalveolar lavage (BAL) fluid of the animals, 6 h after PPE/saline instillation (early time point); and (ii) mean alveolar diameter (μm) and quantification of elastic and collagen fibres (%) 50 days after PPE/saline instillation (late time point). Relative to controls, alloxan-induced diabetic rats showed a 42% reduction in the number of neutrophils in BAL fluid, a 20% increase in the mean alveolar diameter and a 33% decrease in elastic fibre density in the alveolar septa. Treatment of diabetic rats with 4 IU neutral protamine Hagedorn (NPH) insulin, 2 h before elastase instillation, restored the number of neutrophils in the BAL fluid. The mean alveolar diameter and elastic fibre content in alveolar septa matched the values observed in control rats if diabetic rats were treated with 4 IU NPH insulin 2 h before instillation followed by 2 IU/day for the next 50 days. Density of collagen fibres did not differ between the various groups. Thus, the data presented suggest that insulin modulates the inflammatory and repair responses in elastase-induced emphysema, and assures normal repair and tissue remodelling.

Niacin attenuates lung inflammation and improves survival during sepsis by downregulating the nuclear factor-κB pathway

OBJECTIVES

To examine whether niacin attenuates lung inflammation and improves survival during sepsis and to determine whether the beneficial effects of niacin are associated with downregulation of the nuclear factor (NF)-κB pathway.

DESIGN

Prospective laboratory study.

SETTING

University laboratory.

SUBJECTS

Male Sprague-Dawley rats (n = 119).

INTERVENTIONS

To induce endotoxemia in rats, lipopolysaccharide (Escherichia coli, O26:B6) at a dosage of 10 mg/kg was injected into a tail vein and 10 mins later, vehicle, a low dose of niacin (360 mg/kg), or a high dose of niacin (1180 mg/kg) was administered once through an orogastric tube, respectively.

MEASUREMENTS AND MAIN RESULTS

We observed the survival of the subjects for 72 hrs. At 6 hrs postlipopolysaccharide, we euthanized animals and measured cytoplasmic phosphorylated inhibitor κB-α and inhibitor κB-α expressions, nuclear NF-κB p65 expression, NF-κB p65 DNA-binding activity, tumor necrosis factor-α, and interleukin-6 gene expressions and histologic damages in lung tissues. We also measured nicotinamide adenine dinucleotide, reduced nicotinamide adenine dinucleotide phosphate, reduced glutathione, and malondialdehyde levels in lung tissues. High dose of niacin suppressed NF-κB activation and proinflammatory cytokine gene expressions in lung tissues, reduced histologic lung damages, and improved survival in endotoxemic rats. Furthermore, it increased nicotinamide adenine dinucleotide, nicotinamide adenine dinucleotide phosphate, and glutathione levels and decreased malondialdehyde level in lung tissues.

CONCLUSIONS

High dose of niacin attenuated lung inflammation, reduced histologic lung damages, and improved survival during sepsis in rats. These therapeutic benefits were associated with downregulation of the NF-κB pathway.

Inhaled aerosolized insulin: a "topical" anti-inflammatory treatment for acute lung injury and respiratory distress syndrome?

Acute lung injury (ALI) and the more severe acute respiratory distress syndrome (ARDS) are forms of pulmonary edema that result from robust local and systemic inflammatory states, such as sepsis. The morbidity and mortality associated with ALI and ARDS are significant and the treatment of these conditions presents a formidable challenge. Controlling hyperglycemia with insulin is a core component of patient management in the critically ill. Insulin treatment also exerts beneficial metabolic effects beyond glucose control, as well as non-metabolic effects, in insulin-resistant states. For instance, insulin inhibits NF-kappaB--dependent synthesis of pro-inflammatory factors and attenuates production of ROS. Indeed, intravenous administration of insulin ameliorates pulmonary injury and dysfunction in the LPS model of ALI. Most recently, an inhalable insulin formulation was shown to effectively reduce glucose concentrations with minimal impact on long-term pulmonary function. We propose that administering inhalable insulin to hyperglycemic ALI/ARDS patients could directly reduce alveolar inflammation while reducing circulating glucose levels.

Insulin modulates cytokine release and selectin expression in the early phase of allergic airway inflammation in diabetic rats

BACKGROUND

Clinical and experimental data suggest that the inflammatory response is impaired in diabetics and can be modulated by insulin. The present study was undertaken to investigate the role of insulin on the early phase of allergic airway inflammation.

METHODS

Diabetic male Wistar rats (alloxan, 42 mg/Kg, i.v., 10 days) and controls were sensitized by s.c. injection of ovalbumin (OA) in aluminium hydroxide 14 days before OA (1 mg/0.4 mL) or saline intratracheal challenge. The following analyses were performed 6 hours thereafter: a) quantification of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha and cytokine-induced neutrophil chemoattractant (CINC)-1 in the bronchoalveolar lavage fluid (BALF) by Enzyme-Linked Immunosorbent Assay, b) expression of E- and P- selectins on lung vessels by immunohistochemistry, and c) inflammatory cell infiltration into the airways and lung parenchyma. NPH insulin (4 IU, s.c.) was given i.v. 2 hours before antigen challenge.

RESULTS

Diabetic rats exhibited significant reduction in the BALF concentrations of IL-1beta (30%) and TNF-alpha (45%), and in the lung expression of P-selectin (30%) compared to non-diabetic animals. This was accompanied by reduced number of neutrophils into the airways and around bronchi and blood vessels. There were no differences in the CINC-1 levels in BALF, and E-selectin expression. Treatment of diabetic rats with NPH insulin, 2 hours before antigen challenge, restored the reduced levels of IL-1beta, TNF-alpha and P-selectin, and neutrophil migration.

CONCLUSION

Data presented suggest that insulin modulates the production/release of TNF-alpha and IL-1beta, the expression of P- and E-selectin, and the associated neutrophil migration into the lungs during the early phase of the allergic inflammatory reaction.

Genetics vs. entropy: longevity factors suppress the NF-kappaB-driven entropic aging process

Molecular studies in model organisms have identified potent longevity genes which can delay the aging process and extend the lifespan. Longevity factors promote stress resistance and cellular survival. It seems that the aging process itself is not genetically programmed but a random process involving the loss of molecular fidelity and subsequent accumulation of waste products. This age-related increase in cellular entropy is compatible with the disposable soma theory of aging. A large array of host defence systems has been linked to the NF-kappaB system which is an ancient signaling pathway specialized to host defence, e.g. functioning in immune system. Emerging evidence demonstrates that the NF-kappaB system is activated during aging. Oxidative stress and DNA damage increase with aging and elicit a sustained activation of the NF-kappaB system which has negative consequences, e.g. chronic inflammatory response, increase in apoptotic resistance, decline in autophagic cleansing, and tissue atrophy, i.e. processes that enhance the aging process. We will discuss the role of NF-kappaB system in the pro-aging signaling and will emphasize that several longevity factors seem to be inhibitors of NF-kappaB signaling and in that way they can suppress the NF-kappaB-driven entropic host defence catastrophe.

Evaluation of the effects of ozone therapy in the treatment of intra-abdominal infection in rats

INTRODUCTION

The antibacterial effect of ozone (O(3)) has been described in the extant literature, but the role of O(3) therapy in the treatment of certain types of infection remains controversial.

OBJECTIVES

To evaluate the effect of intraperitoneal (i.p.) O(3) application in a cecal ligation/puncture rat model on interleukins (IL-6, IL-10) and cytokine-induced neutrophil chemoattractant (CINC)-1 serum levels, acute lung injury and survival rates.

METHODS

FOUR ANIMAL GROUPS WERE USED FOR THE STUDY: a) the SHAM group underwent laparotomy; b) the cecal ligation/puncture group underwent cecal ligation/puncture procedures; and c) the CLP+O(2) and CLP+O(3) groups underwent CLP+ corresponding gas mixture infusions (i.p.) throughout the observation period. IL-6, CINC-1 and IL-10 concentrations were determined by enzyme-linked immunosorbent assay (ELISA). Acute lung injury was evaluated with the Evans blue dye lung leakage method and by lung histology. P<0.05 was considered significant.

RESULTS

CINC-1 was at the lowest level in the SHAM group and was lower for the CLP+O(3) group vs. the CLP+O(2) group and the cecal ligation/puncture group. IL-10 was lower for the SHAM group vs. the other three groups, which were similar compared to each other. IL-6 was lower for the SHAM group vs. all other groups, was lower for the CLP+O(3) or CLP+O(2) group vs. the cecal ligation/puncture group, and was similar for the CLP+O(3) group vs. the CLP+O(2) group. The lung histology score was lower for the SHAM group vs. the other groups. The Evans blue dye result was lower for the CLP+O(3) group vs. the CLP+O(2) group and the cecal ligation/puncture group but similar to that of the SHAM group. The survival rate for the CLP+O(3) group was lower than for the SHAM group and similar to that for the other 2 groups (CLP and CLP+O(2)).

CONCLUSION

Ozone therapy modulated the inflammatory response and acute lung injury in the cecal ligation/puncture infection model in rats, although there was no improvement on survival rates.