Cytokine secretion is impaired in women with diabetes mellitus

Triple threat: how diabetes results in worsened bacterial infections

Diabetes mellitus, characterized by impaired insulin signaling, is associated with increased incidence and severity of infections. Various diabetes-related complications contribute to exacerbated bacterial infections, including hyperglycemia, innate immune cell dysfunction, and infection with antibiotic-resistant bacterial strains. One defining symptom of diabetes is hyperglycemia, resulting in elevated blood and tissue glucose concentrations. Glucose is the preferred carbon source of several bacterial pathogens, and hyperglycemia escalates bacterial growth and virulence. Hyperglycemia promotes specific mechanisms of bacterial virulence known to contribute to infection chronicity, including tissue adherence and biofilm formation. Foot infections are a significant source of morbidity in individuals with diabetes and consist of biofilm-associated polymicrobial communities. Bacteria perform complex interspecies behaviors conducive to their growth and virulence within biofilms, including metabolic cross-feeding and altered phenotypes more tolerant to antibiotic therapeutics. Moreover, the metabolic dysfunction caused by diabetes compromises immune cell function, resulting in immune suppression. Impaired insulin signaling induces aberrations in phagocytic cells, which are crucial mediators for controlling and resolving bacterial infections. These aberrancies encompass altered cytokine profiles, the migratory and chemotactic mechanisms of neutrophils, and the metabolic reprogramming required for the oxidative burst and subsequent generation of bactericidal free radicals. Furthermore, the immune suppression caused by diabetes and the polymicrobial nature of the diabetic infection microenvironment may promote the emergence of novel strains of multidrug-resistant bacterial pathogens. This review focuses on the "triple threat" linked to worsened bacterial infections in individuals with diabetes: (i) altered nutritional availability in diabetic tissues, (ii) diabetes-associated immune suppression, and (iii) antibiotic treatment failure.

Association between diabetes mellitus and reduced efficacy of pembrolizumab in non-small cell lung cancer

BACKGROUND

Diabetes mellitus (DM) is a highly prevalent chronic metabolic disorder. Although DM has been associated with immune dysfunction, the effect of DM on the efficacy of immunotherapy is unknown. This study aimed to evaluate the impact of DM on the efficacy of pembrolizumab in metastatic non-small cell lung cancer (NSCLC).

METHODS

The authors reviewed the medical records of consecutive metastatic NSCLC patients treated with first-line pembrolizumab either alone or in combination with chemotherapy at a single tertiary center. For validation, a computerized data from Maccabi Healthcare Services, a 2.5-million-member state health service was used.

RESULTS

Of the 203 eligible patients, 51 (25%) had DM. Patients with DM had a significantly shorter median progression-free survival (PFS) (5.9 vs. 7.1 months, p = .004) and overall survival (OS) (12 vs. 21 months, p = .006). The shorter OS in diabetic patients was more pronounced when pembrolizumab was given alone (12 vs. 27 months, p = .03) than when combined with chemotherapy (14.3 vs. 19.4 months, p = .06). Multivariate analysis confirmed DM as an independent risk factor for shorter PFS (hazard ratio [HR], 1.67; 95% confidence interval [CI], 1.11-2.50, p = .01) and OS (HR, 1.73; 95% CI, 1.09-2.76, p = .02). In a validation cohort of 452 metastatic NSCLC patients, the time on pembrolizumab treatment was shorter in diabetic patients (p = .025), with only 19.6% of patients remaining on treatment at 12 months compared to 31.7% of the nondiabetic patients.

CONCLUSIONS

This study suggests immunotherapy is less beneficial in diabetic NSCLC patients. More work is needed to verify our findings and explore similar effects in other cancer entities.

Role of metabolism in uropathogenic Escherichia coli

Uropathogenic Escherichia coli (UPEC) is responsible for more than 75% of urinary tract infections (UTIs) and has been studied extensively to better understand the molecular underpinnings of infection and pathogenesis. Although the macromolecular adaptations UPEC employs - including the expression of virulence factors, adhesion molecules, and iron-acquisition systems - are well described, the role that metabolism plays in enabling infection is still unclear. However, a growing body of literature shows that metabolic function can have a profound impact on which strains can colonize the urinary tract. The goal of this review is to critically appraise this emerging body of literature to better understand the role that nutritional selection plays in enabling urinary tract colonization and the progression of UTIs.

Obesity, Diabetes Mellitus, and Metabolic Syndrome: Review in the Era of COVID-19

Coronavirus disease 2019 (COVID-19), a novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is now at pandemic levels leading to considerable morbidity and mortality throughout the globe. Patients with obesity, diabetes, and metabolic syndrome (MetS) are mainly susceptible and more probably to get severe side effects when affected by this virus. The pathophysiologic mechanisms for these notions have not been completely known. The pro-inflammatory milieu observed in patients with metabolic disruption could lead to COVID-19-mediated host immune dysregulation, such as immune dysfunction, severe inflammation, microvascular dysfunction, and thrombosis. The present review expresses the current knowledge regarding the influence of obesity, diabetes mellitus, and MetS on COVID-19 infection and severity, and their pathophysiological mechanisms.

Antibiotic prophylaxis in patients who had undergone to prostate biopsy in between the EMA warning era: effects of fluoroquinolones in diabetic and non-diabetic patients. Results of an observational cohort study

Purpose

To investigate the effects of different antibiotic prophylaxis regimens in patients with diabetes mellitus (DM) candidates to trans-rectal ultrasound-guided prostate biopsy (TRUSPB).

Methods

143 outpatients with DM who underwent TRUSPB during the period 2018–2020 were selected from a cohort of 1150 patients in 3 different institutions. Exclusion criteria were allergies, concomitant anti-platelet therapies and uncontrolled DM. Different antibiotic prophylaxis regimens were adopted. Bacterial resistance levels to fluoroquinolones into the different communities were also collected. Univariable and multivariable binomial logistic regression analyses were used to assess the odds ratio (OR) with 95% confidence intervals (CIs) testing the risk of infective complications' occurrence after adjusting for clinical covariates.

Results

Overall, DM patients were significantly associated with infective complications' occurrence (p < 0.001). No differences on the event of sepsis were found between diabetic and non-diabetic patients. Clinically relevant infections with fever > 37 °C were found in 9.1% and 1.5% (p < 0.001) in diabetic and non-diabetic patients, respectively. Trimethoprim–sulphametoxazole and fluoroquinolones were six times more efficient than Cefixime in non-diabetic patients. Fluoroquinolones confirmed the same effect in diabetic patients although the level of resistance in the period of study decreased only from 56 to 46%.

Conclusion

Fluoroquinolones were active in antibiotic prophylaxis of diabetic patients who had undergone to TRUSPB independently from the level of bacterial resistance found in the community. These results conflict with the recent European warning and support the Japanese and American guidelines on the topic.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00345-022-04055-7.

Glycosuria Alters Uropathogenic Escherichia coli Global Gene Expression and Virulence

Uropathogenic Escherichia coli (UPEC) is the principal etiology of more than half of urinary tract infections (UTI) in humans with diabetes mellitus. Epidemiological data and studies in mouse model of ascending UTI have elucidated various host factors responsible for increasing the susceptibility of diabetic hosts to UPEC-UTI. In contrast, diabetic urinary microenvironment-mediated alterations in UPEC physiology and its contributions to shaping UPEC-UTI pathogenesis in diabetes have not been examined. To address our central hypothesis that glycosuria directly induces urinary virulence of UPEC, we compared virulence characteristics and gene expression in human UPEC strains UTI89 (cystitis) and CFT073 (pyelonephritis), exposed for 2 h in vitro to urine from either male or female donors that was either plain or supplemented with glucose to mimic glycosuria. Compared to control UPEC exposed to nutrient-rich culture medium, lysogeny broth, glycosuria-exposed UPEC exhibited significant increase in biofilm formation and reduction in the hemagglutination of Guinea pig erythrocytes (a measure of type 1 piliation). In addition, the analysis of UTI89 transcriptome by RNA sequencing revealed that 2-h-long, in vitro exposure to glycosuria also significantly alters expression of virulence and metabolic genes central to urinary virulence of UPEC. Addition of galactose as an alternative carbon source affected biofilm formation and gene expression profile of UPEC to an extent similar to that observed with glucose exposure. In summary, our results provide novel insights into how glycosuria-mediated rapid changes in UPEC fitness may facilitate UTI pathogenesis in the diabetic urinary microenvironment.

IMPORTANCE Uropathogenic Escherichia coli (UPEC) is an important causative agent of urinary tract infections in diabetic humans. We examined the effects of in vitro exposure to glycosuria (presence of glucose in urine) on the virulence and gene expression by UPEC. Our results show that glycosuria rapidly (in 2 h) alters UPEC gene expression, induces biofilm formation, and suppresses type 1 piliation. These results offer novel insights into the pathogenesis of UPEC in the urinary tract.

An Overview of Systematic Reviews of the Role of Vitamin D on Inflammation in Patients with Diabetes and the Potentiality of Its Application on Diabetic Patients with COVID-19

Almost two years have passed since the outbreak reported for the first time in Wuhan of coronavirus disease 2019 (COVID-19), due to severe acute respiratory syndrome (SARS)-CoV-2 coronavirus, rapidly evolved into a pandemic. This infectious disease has stressed global health care systems. The mortality rate is higher, particularly in elderly population and in patients with comorbidities such as hypertension, diabetes mellitus, cardiovascular disease, chronic lung disease, chronic renal disease, and malignancy. Among them, subjects with diabetes have a high risk of developing severe form of COVID-19 and show increased mortality. How diabetes contributes to COVID-19 severity remains unclear. It has been hypothesized that it may be correlated with the effects of hyperglycemia on systemic inflammatory responses and immune system dysfunction. Vitamin D (VD) is a modulator of immune-response. Data from literature showed that vitamin D deficiency in COVID-19 patients increases COVID-19 severity, likely because of its negative impact on immune and inflammatory responses. Therefore, the use of vitamin D might play a role in some aspects of the infection, particularly the inflammatory state and the immune system function of patients. Moreover, a piece of evidence highlighted a link among vitamin D deficiency, obesity and diabetes, all factors associated with COVID-19 severity. Given this background, we performed an overview of the systematic reviews to assess the association between vitamin D supplementation and inflammatory markers in patients with diabetes; furthermore, vitamin D’s possible role in COVID-19 patients was assessed as well. Three databases, namely MEDLINE, PubMed Central and the Cochrane Library of Systematic Reviews, were reviewed to retrieve the pertinent data. The aim of this review is to provide insight into the recent advances about the molecular basis of the relationship between vitamin D, immune response, inflammation, diabetes and COVID-19.

Perioperative glycemic status is linked to postoperative complications in non-intensive care unit patients with type-2 diabetes: a retrospective study

BACKGROUND

Perioperative hyperglycemia is a risk factor for postoperative complications in the general population. However, it has not been clarified whether perioperative hyperglycemia increases postoperative complications in patients with type-2 diabetes mellitus (T2D). Therefore, we aimed to analyze the relationship between perioperative glycemic status and postoperative complications in non-intensive care unit (non-ICU) hospitalized patients with T2D.

MATERIALS AND METHODS

Medical records of 1217 patients with T2D who were admitted to the non-ICU in our hospital were analyzed retrospectively. Relationships between clinical characteristics including perioperative glycemic status and postoperative complications were assessed using univariate and multivariate analyses. Perioperative glycemic status was evaluated by calculating the mean, standard deviation (SD), and coefficient of variation (CV) of blood glucose (BG) measurements in preoperative and postoperative periods for three contiguous days before and after surgery, respectively. Postoperative complications were defined as infections, delayed wound healing, postoperative bleeding, and/or thrombosis.

RESULTS

Postoperative complications occurred in 139 patients (11.4%). These patients showed a lower BG immediately before surgery (P = 0.04) and a higher mean postoperative BG (P = 0.009) than those without postoperative complications. There were no differences in the other perioperative BG parameters including BG variability and the frequency of hypoglycemia. The multivariate analysis showed that BG immediately before surgery (adjusted odds ratio (95% confidence interval [CI]), 0.91 (0.85-0.98), P = 0.01) and mean postoperative BG (1.11 (1.05-1.18), P < 0.001) were independently associated with postoperative complications.

CONCLUSION

Perioperative glycemic status, that is, a low BG immediately before surgery and a high mean postoperative BG, are associated with the increased incidence of postoperative complications in non-ICU patients with T2D.

Systematic Review of Literature Examining Bacterial Urinary Tract Infections in Diabetes

This systematic review addresses the central research question, "what is known from the published, peer-reviewed literature about the impact of diabetes on the risk of bacterial urinary tract infections (UTI)?" We examine the results from laboratory studies where researchers have successfully adapted mouse models of diabetes to study the pathophysiology of ascending UTI. These studies have identified molecular and cellular effectors shaping immune defenses against infection of the diabetic urinary tract. In addition, we present evidence from clinical studies that in addition to diabetes, female gender, increased age, and diabetes-associated hyperglycemia, glycosuria, and immune impairment are important risk factors which further increase the risk of UTI in diabetic individuals. Clinical studies also show that the uropathogenic genera causing UTI are largely similar between diabetic and nondiabetic individuals, although diabetes significantly increases risk of UTI by drug-resistant uropathogenic bacteria.

Infectious diseases associated with pediatric type 1 diabetes mellitus: A narrative review

Diabetes mellitus (DM) has been frequently associated with an impaired immune response against infectious agents, making affected patients at risk for more severe disease and sometimes causing worse outcomes. The recent COVID-19 pandemic has seriously affected patients with both diabetes, in particular those carrying comorbidities or with poor glycemic control. As regards pediatric diabetes mellitus, the availability of more accurate and technological tools for glycemic management and the improved markers of metabolic control might mitigate the negative impact of infections. Notably, good metabolic control of diabetes since its diagnosis reduces not only the risk of microangiopathic complications but also of impaired immune response to infectious diseases. Therefore, vaccinations are strongly recommended. Our paper aims to provide the most updated evidence regarding infectious diseases in type 1 pediatric DM.

Understanding the increased risk of infections in diabetes: innate and adaptive immune responses in type 1 diabetes

AIMS

Patients with diabetes have a higher incidence of infections with Candida albicans, Staphylococcus aureus and Mycobacterium tuberculosis, yet factors contributing to this increased risk are largely unknown. We hypothesize that altered innate and adaptive immune responses during diabetes contribute to an increased susceptibility to infections.

MATERIALS AND METHODS

We studied cytokine responses to ex vivo pathogenic stimulations in a cohort with type 1 diabetes (n = 243) and non-diabetic healthy control subjects (n = 56) using isolated peripheral blood mononuclear cells (PBMCs). Clinical phenotypical data including BMI, duration of diabetes, and HbA_1c levels were collected and related to the cytokine production capacity.

RESULTS

Adjusted for age, sex and BMI, the presence of diabetes was associated with significantly lower IL-1β, IL-6, TNF-α, and IL-17 production upon ex vivo stimulation of PBMCs with C. albicans and S. aureus (all, p < 0.05). In response to stimulation with M. tuberculosis only IL-17 (p < 0.001) was lower in patients with diabetes. Patients with the shortest diabetes duration had a significant lower IL-1β, IL-6 and TNF-α production (all, p < 0.01) after M. tuberculosis stimulation. Older patients had a significant lower IFN-γ (p < 0.05) production after stimulation with all three pathogens. HbA_1c levels and BMI had no significant impact on cytokine production.

CONCLUSIONS

PBMCs of patients with type 1 diabetes demonstrate significantly lower cytokine production in response to stimulation with several pathogens, which likely explain, at least in part, the increased susceptibility for these infections.

Complicated urinary tract infections with diabetes mellitus

Patients with diabetes mellitus (DM) sometimes exhibited impaired immune function and aggravated infectious diseases. Urinary tract infection (UTI) is one of the major complications of DM. A systematic literature search was performed in PubMed and Cochrane Library using the following keywords: diabetes mellitus, urinary tract infection, asymptomatic bacteriuria, emphysematous pyelonephritis, emphysematous cystitis, renal papillary necrosis, and sodium-glucose co-transporter 2 (SGLT2) inhibitors. The treatment of UTI in DM patients is not different from that in non-DM patients, and asymptomatic bacteriuria should not be screened or treated. Emphysematous pyelonephritis is a life-threatening renal infection with gas in the renal parenchyma or perirenal space, and 95% of affected patients had DM. Abdominal computed tomography is useful for diagnosis and determining treatment strategies. Medical management and percutaneous drainage are standard initial treatment, and subsequent nephrectomy for non-responders is considered. Nephrectomy, as an initial treatment, should be limited to a selected group of patients with severe conditions. In contrast, antibiotics, glycemic control, and bladder drainage are adequate treatment for most cases of emphysematous cystitis. SGLT2 inhibitors significantly increased the incidence of genital tract infection, but not that of UTI, pyelonephritis, or urosepsis. Here, we present cumulative evidence about etiology and management for complicated UTI with DM, but there was little information about racial differences and further evidence focusing on Asian population will be needed.

Chemokines in Prediabetes and Type 2 Diabetes: A Meta-Analysis

Background

A growing number of studies found inconsistent results on the role of chemokines in the progression of type 2 diabetes (T2DM) and prediabetes (PDM). The purpose of this meta-analysis was to summarize the results of previous studies on the association between the chemokines system and T2DM/PDM.

Methods

We searched in the databases, PubMed, Web of Science, Embase and Cochrane Library, for eligible studies published not later than March 1, 2020. Data extraction was performed independently by 2 reviewers, on a standardized, prepiloted form. Group differences in chemokines concentrations were summarized using the standardized mean difference (SMD) with a 95% confidence interval (CI), calculated by performing a meta-analysis using the random-effects model.

Results

We identified 98 relevant studies that investigated the association between 32 different chemokines and T2DM/PDM. Altogether, these studies involved 14,708 patients and 14,574 controls. Results showed that the concentrations of CCL1, CCL2, CCL4, CCL5, CCL11, CXCL8, CXCL10 and CX3CL1 in the T2DM patients were significantly higher than that in the controls, while no difference in these concentrations was found between the PDM patients and controls.

Conclusion

Progression of T2DM may be associated with elevated concentrations of chemokines.

Meta-Analysis Registration

PROSPERO, identifier CRD42019148305.

The evaluation of intracellular energy metabolism in prediabetic patients and patients newly diagnosed with type 2 diabetes mellitus

Background/aim

Increased susceptibility to infections is a serious problem in diabetics. Impairment in the energy metabolism of the immune system is the main source of the problem. Early diagnosis of the impairment in energy metabolism is crucial. Our study aimed to investigate the energy metabolism in leukocytes in patient groups such as prediabetics and patients newly diagnosed with type 2 diabetes mellitus.

Materials and methods

Our study included 21 newly diagnosed type 2 diabetic patients (NDDP), 30 prediabetic patients, and 22 adult volunteers. 75 g oral glucose tolerance test (OGTT) was applied to all patients included in the study. Blood samples were taken after 9-16 h of fasting and fasting blood glucose (FBG), postprandial blood glucose (PBG) levels, total cholesterol (TC), triglyceride (TG), high- density lipoprotein (HDL), fasting serum insulin, and hemoglobin A1c (HbA1c) levels were evaluated. After the cells were completely lysed, citrate levels from the released mononuclear leukocyte cells (MNC) content were manually studied, and lactate levels were applied to the autoanalyzer with the lactate kit. Lactate and citrate results were calculated as μg/mL. Statistical comparisons were done using Chi-square test, Mann-Whitney U test and student’s t test, and P < 0.05 values were accepted as significant.

Results

A significant difference was found between the controls and the other groups (newly diagnosed diabetic patients (NDDP), impaired fasting glucose (IFG), and impaired glucose tolerance (IGT)) in terms of FBG levels (P < 0.001, P < 0.001 and P < 0.001, respectively). IFG and IGT patients had significantly higher PBG levels compared to the control group (P = 0.009 and P < 0.001, respectively). There was a significant difference between the IFG and IGT patients in terms of insulin levels (P = 0.019). There was a significant relationship between FBG levels and lactate production only in the NDDP group (r = 0.610, P = 0.003)

Conclusion

The metabolic effects of hyperglycemia on leukocytes is in direction of anaerobic glycolysis. The increased anaerobic pathway is closely related to blood glucose levels and insulin resistance.

COVID-19 and diabetes mellitus: how one pandemic worsens the other

In light of the most challenging public health crisis of modern history, COVID-19 mortality continues to rise at an alarming rate. Patients with co-morbidities such as hypertension, cardiovascular disease, and diabetes mellitus (DM) seem to be more prone to severe symptoms and appear to have a higher mortality rate. In this review, we elucidate suggested mechanisms underlying the increased susceptibility of patients with diabetes to infection with SARS-CoV-2 with a more severe COVID-19 disease. The worsened prognosis of COVID-19 patients with DM can be attributed to a facilitated viral uptake assisted by the host's receptor angiotensin-converting enzyme 2 (ACE2). It can also be associated with a higher basal level of pro-inflammatory cytokines present in patients with diabetes, which enables a hyperinflammatory "cytokine storm" in response to the virus. This review also suggests a link between elevated levels of IL-6 and AMPK/mTOR signaling pathway and their role in exacerbating diabetes-induced complications and insulin resistance. If further studied, these findings could help identify novel therapeutic intervention strategies for patients with diabetes comorbid with COVID-19.

(-)-Epicatechin and the colonic metabolite 2,3-dihydroxybenzoic acid protect against high glucose and lipopolysaccharide-induced inflammation in renal proximal tubular cells through NOX-4/p38 signalling

Chronic hyperglycaemia and inflammation are present in diabetes and both processes have been related to the pathogenesis of diabetic kidney disease. Epicatechin (EC) and main colonic phenolic acids derived from flavonoid intake, such as 2,3-dihydroxybenzoic acid (DHBA), 3,4-dihydroxyphenylacetic acid (DHPAA) and 3-hydroxyphenylpropionic acid (HPPA), have been suggested to exert beneficial effects in diabetes. This study was aimed at investigating whether the mentioned compounds could prevent inflammation in renal proximal tubular NRK-52E cells induced by high glucose and lipopolysaccharide (LPS). Pre-treatment of cells with EC and DHBA (5 μM) reverted the enhanced levels of pro-inflammatory cytokines, such as tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6) and monocyte chemoattractant protein 1 (MCP-1), activated by high glucose and LPS. Additionally, EC and DHBA pre-incubation reduced the increased values of adhesion molecules, namely, intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), as well as those of mitogen-activated protein kinases (MAPKs) [extracellular signal-regulated kinase (ERK), -c-jun N-terminal kinase (JNK) and -p38 protein kinase (p38)] activated by the high glucose and LPS challenge. Thus, in EC and DHBA pre-treated cells ICAM-1, p-ERK and p-JNK were returned to control values, and VCAM-1 and p-p38 levels were reduced by ∼20 and 25%, respectively, when compared to high glucose plus LPS-stimulated cells. Likewise, pre-treatment with EC and DHBA protected against high glucose plus LPS-triggered oxidative stress by preventing increased ROS and NADPH oxidase 4 (NOX-4) levels (∼25 and 45% reduction, respectively). By using specific inhibitors of p38 and NOX-4, the participation of both proteins in EC- and DHBA-mediated protection against inflammation and associated oxidative stress was shown. Taken together, EC and DHBA exert beneficial effects in renal proximal tubular cells, as they contribute to preventing the inflammatory-induced milieu and the accompanying redox imbalance, playing NOX-4/p38 a crucial role.

Comparison of Incidence of Urinary Tract Infection in Diabetic vs Non-Diabetic and Associated Pathogens

Introduction

Urinary tract infections (UTIs) are common in low socioeconomic country like Pakistan. There are various factors responsible for UTI, one major factor being diabetes. This study aims to compare diabetic and non-diabetic patients, for gender association, symptoms, and organisms, with UTI.

Methods 

This cross-sectional study was conducted in the medicine ward of tertiary care hospital in Pakistan from January 2019 to December 2019. For urine analysis, freshly voided 5-10 ml of clean midstream urine specimens was collected in a sterile container. Samples were sent to the lab immediately, A colony count of ≥10⁵ CFU/ml was considered for the diagnosis of UTI. Culture was done if UTI was diagnosed.

Results 

The overall incidence of UTI in participants of the diabetic group was significantly higher than those in the non-diabetic group (13.67% vs 6.40%; P=0.004). Escherichia coli was the most common organism in both the diabetic and non-diabetic groups (60% vs 72%; P=0.73). Frequency of Klebsiella was considerably higher in the participants of diabetes but it was not significant (23.3% vs 11.1%; P=0.29).

Conclusion 

UTI was significantly higher in the diabetic population compared to the non-diabetic population. Since diabetes is prevalent in Pakistan, care of diabetes should include reducing the risk factors for UTI.

Diabetes and COVID-19: A Review

Coronavirus Disease 2019 (COVID-19) is an emerging disease and since its first identification in Wuhan, China, in December 2019, there has been a rapid increase in cases and deaths across the world. COVID-19 has been shown to have an immense impact in infected persons with diabetes, worsening their outcome, especially in elderly, smokers, obese, those having CVD, CKD, poor glycemic control and long duration of diabetes. In this review we summarize the current understanding of `the impact of COVID-19 on diabetes and discusses the pathophysiological mechanisms and management of diabetes and its complication in this scenario.

Evaluation of the Activity of Neutrophils and Monocytes in Diabetic Patients With Sepsis, Can Surface Antigens HLA-DR and CD64 Be Useful as Prognostic Factors?

Background

Patients with diabetes mellitus (DM) exhibit alterations in their immune response when infected by several types of micro-organisms. The increased susceptibility of diabetics to infections is particularly related to abnormalities in the function of neutrophils such as chemotaxis, adhesion and intracellular killing, leading to increased mortality rates. Aims of the study were to assess the phagocytic activity and the expression of antigens HLA-DR and CD64 of monocytes and neutrophils in diabetics with sepsis and evaluate their significance as prognostic factors.

Methods

This is an observational prospective study conducted in a tertiary medical center, referring to a population of 51 diabetic patients who were treated for sepsis. Samples of whole blood were received from the selected patients and were evaluated for the expression of surface antigens HLA-DR and CD64 on monocytes and neutrophils, and for their phagocytic activity as well.

Results

Alterations in the phagocytic activity were found in the diabetic patients who developed sepsis, and these were addressed as an elevation in the expression of CD64 on monocytes (CD64M), and a reduction in the expression of HLA-DR on monocytes (HLA-DRM) at least in the initial phase of the acute infection. A significant elevation was also noticed in the phagocytosis rate of both neutrophils and monocytes on day of admission. Survivors had higher rates of both CD64 and HLA-DR on monocytes when compared to non-survivors. No correlation was found between glycemic control, values of inflammatory markers on admission, phagocytosis rate and the survival of diabetics with sepsis. A reduced expression of CD64O, HLA-DRM and the co-expression of CD64/HLA-DR on monocytes in the initial phase of sepsis and poor glycemic control (hemoglobin A1c (HbA1c) > 8.5) was found.

Conclusions

In the present study of diabetic patients with sepsis the phagocytic activity of neutrophils and monocytes is elevated at the initial phase of an acute infection and only the values of CD64 and HLA-DR on monocytes were significantly related to outcome. Further evaluation of these results with large prospective studies is warranted.

Interleukin-6 and Interleukin-15 as Possible Biomarkers of the Risk of Autoimmune Diabetes Development

Aim

The aim of our study was to assay circulating interleukin-15 (IL-15) and interleukin-6 (IL-6) levels and insulin resistance measured by two different methods in newly diagnosed autoimmune diabetes (AD) patients, their I° relatives, and healthy controls.

Material and Methods

The group studied consisted of 54 patients with AD (28 with Latent Autoimmune Diabetes in Adults (LADA) and 26 with type 1 diabetes (T1D)), 70 first-degree relatives, and 60 controls. IL-6, IL-15, and anti-islet antibodies concentrations were measured by ELISA method. Homeostatic model assessment-insulin resistance (HOMAIR) and estimated glucose disposal rate (eGDR) were calculated.

Results

The patients with AD had significantly higher IL-15, IL-6, and HOMAIR and lower eGDR than the controls (p < 0.001, respectively) and first-degree relatives (p < 0.001, respectively). Significantly higher IL-15 and IL-6 were shown in the relatives with positive Ab as compared to the relatives without antibodies (p < 0.001, respectively) and the controls (p < 0.001, respectively). IL-15 negatively correlated with eGDR (r = −0.436, p = 0.021) in LADA and positively with HOMAIR in LADA and T1D (r = 0.507, p < 0.001; r = 0.4209, p < 0.001).

Conclusions

Significantly higher IL-15 and IL-6 concentrations, HOMAIR, and markedly lower eGDR in newly diagnosed AD patients and first-degree relatives with positive anti-islet antibodies might suggest the role of these pro-inflammatory cytokines and insulin resistance in the pathogenesis of autoimmune diabetes. IL-15 and IL-6 might be used as biomarkers of the risk of autoimmune diabetes development, in particular IL-15 for LADA. Both methods of IR measurement appear equally useful for calculating insulin resistance in autoimmune diabetes.

Diabetes and the solid organ transplant recipient

Solid organ transplant candidates undergo very strict screening for cardiovascular risk. Such screening has permitted significant decreases in cardiovascular morbidity and mortality over the ensuing decades of follow up. Long term follow-up has enabled us to identify an increasing incidence of pulmonary and urinary tract infections with or without sepsis as competing factors of morbidity and mortality. Indeed, all-cause mortality may now be dominated by infection-related endpoints. No population of transplant recipients is more naturally susceptible to infection as a diabetic subset, now submitted to immunosuppression. The current review details infection risk for kidney, liver, heart, and lung allograft recipients. A specific feature of this report emphasizes the enhanced risk for bacterial and fungal infection found in diabetic allograft recipients on immunosuppression therapy. The risk of repeated prescription of antibiotics in terms of evolutions of resistant strains of infectious pathogens is emphasized.

Immune and vascular dysfunction in diabetic wound healing

The diminished capacity for wound healing in patients with diabetes contributes to morbidity through ulceration and recurrent infections, loss of function and decreased workplace productivity, increased hospitalisation rates, and rising health-care costs. These are due to diabetes' effects on signalling molecules, cellular cascades, different cell populations, and the vasculature. The function of multiple immune system components including cellular response, blood factors, and vascular tone are all negatively impacted by diabetes. The purpose of this paper is to review the current understanding of immune and vascular dysfunction contributing to impaired wound healing mechanisms in the diabetic population. Normal wound healing mechanisms are reviewed followed by diabetic aberrations to immune and inflammatory function and atherogenesis and angiopathy.

DECLARATION OF INTEREST

The authors have no financial or personal relationships to people or organisations that could potentially and inappropriately influence their work and conclusions.

Beneficial Effect of Intestinal Fermentation of Natural Polysaccharides

With the rapid development of modern society, many chronic diseases are increasing including diabetes, obesity, cardiovascular diseases, etc., which further cause an increased death rate worldwide. A high caloric diet with reduced natural polysaccharides, typically indigestible polysaccharides, is considered a health risk factor. With solid evidence accumulating that indigestible polysaccharides can effectively prevent and/or ameliorate symptoms of many chronic diseases, we give a narrative review of many natural polysaccharides extracted from various food resources which mainly contribute their health beneficial functions via intestinal fermentation.

D-pinitol attenuates cisplatin-induced nephrotoxicity in rats: Impact on pro-inflammatory cytokines

Cisplatin has been widely used as a first-line agent against various forms of solid cancers. However, nephrotoxicity is the major limiting factor for its clinical use. Several clinical and pre-clinical studies have suggested different strategies for the reduction of cisplatin-induced nephrotoxicity. The present study was conducted to investigate the efficacy of D-Pinitol, against cisplatin-induced nephrotoxicity in Swiss albino mice. A single intraperitoneal injection of cisplatin (20 mg/kg) was used to induce nephrotoxicity in mice. Administration of cisplatin in mice is linked with elevated oxidative stress, imbalanced biochemical parameters, apoptosis and stimulation of mitogen-activated protein kinase (MAPK) pathway. D-Pinitol is a member of the flavonoid family and a chief constituent of Sutherlandia fruitesecnce. It was administered with saline water (10, 20, 40 mg/kg, p.o.) for seven consecutive days after a single dose of cisplatin. At the end of experiment, animals were sacrificed and biochemical parameters in serum and urine were recorded. Kidneys were isolated for the estimation of tumor necrosis factor-alpha, interleukin-1β, interlukin-6 levels and histopathological evaluations. It was noted that D-Pinitol significantly ameliorated biochemical levels of serum and urinary creatinine and blood urea nitrogen. Tissue homogenate levels of TNF-α, IL-6, IL-1β and the renal expression of tissue nitrites were also significantly decreased in D-Pinitol treated mice. These results were supplemented by histopathological findings. This study highlights the potential role of D-Pinitol against cisplatin-induced toxicity, exhibited through favorable alterations in biochemical and histological changes as well as reduction in oxidative stress and cytokine levels.

Impaired Inflammatory Response to LPS in Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is a severe health problem worldwide, reaching epidemic levels. High susceptibility to infections of T2DM patients indicates dysregulated immune responses to pathogens. However, innate immune responses, including monocyte functions, in T2DM are poorly investigated. Therefore, in this study we aimed to assess lipopolysaccharide- (LPS-) induced immune responses of circulating monocytes from T2DM patients. The results showed that monocytes from T2DM were hyporesponsive to LPS challenge as reflected by significantly suppressed secretion of TNFα (p < 0.01) and expression of CD11b (p < 0.001) and TLR4 (p < 0.001) compared to those in monocytes from healthy subjects. Furthermore, LPS-induced IL-10 levels were similar in diabetic and healthy supernatants, while expression levels of CD163 were found to be downregulated on monocytes from T2DM (p < 0.001) suggesting impaired ability of monocytes to switch their phenotype to anti-inflammatory. Taken together, our results suggest compromised function of monocytes in T2DM, which may explain, at least partly, high incidence of infection in these patients.

The Predictive Value of Glycated Hemoglobin and Albumin for the Clinical Course Following Hospitalization of Patients with Febrile Urinary Tract Infection

Background

Diabetes is considered a risk factor for acquisition of febrile urinary tract infection (f-UTI), but information on the association of diabetes with subsequent course of the disease is lacking. Thus, we investigated the clinical variables including diabetic status which determined the clinical course in patients with community-acquired f-UTI.

Materials and Methods

Patients hospitalized consecutively for f-UTI between February 2016 and January 2018 were used for this single center study. The routine laboratory tests including blood glucose and glycated hemoglobin (HbA1c) were done and empiric treatment with parenteral antibiotics was commenced on admission. The clinical course such as duration of fever (DOF) and length of hospital stay (LOS) were compared among groups classified by the clinical variables.

Results

Among the101 patients admitted for f-UTI, 15 patients with diabetes (14.9%) experienced significantly longer febrile period and hospitalization compared to those with hyperglycemia (n = 18, 17.8%) or those without diabetes and hyperglycemia (n = 68, 67.3%). Of the laboratory parameters tested on admission and several clinical factors, the presence of diabetes and risk factors for severe complicated infection (hydronephrosis, urosepsis, and disseminated intravascular coagulopathy) as well as HbA1c and albumin were identified as predictors for LOS by univariate analysis, whereas none of the variables failed to predict DOF. In the subsequent multivariate analysis, HbA1c levels and albumin levels were isolated as independent predictors of LOS.

Conclusion

Patients with higher HbA1c and lower albumin levels required the longest period of hospitalization. Thus, an evaluation of diabetic and nutritional status on admission will be feasible to foretell the clinical course and better manage the subset of patients at risk of prolonged hospitalization.

Epidural abscess imitating recurrent pilonidal sinus: a case report

Pilonidal sinus or pilonidal cyst is a common benign disease, affecting mostly young working men. We present the first case of an epidural abscess imitating pilonidal sinus. A 33-year old male, suffering from previously undiagnosed and untreated diabetes mellitus (DM), presented to our emergency department (ER), one month after open surgical treatment of pilonidal sinus, due to weakness and fever. After re-operation of the pilonidal cyst and due to post-operative pus production and continuation of fever a computer tomogr aphy (CT )scan was performed revealing an epidural abscess extending from the thoracic vertebrae 12 (T-12) to the sacrococcygeal area. At that point he underwent new surgery for drainage of the epidural abscess. The patient received intravenous antimicrobial treatment and was discharged on the 23rd postoperative day without signs or symptoms of infection. At follow up for a whole year no signs of recurrence have been observed.

Diabetes mellitus increases the susceptibility to encephalitozoonosis in mice

Microsporidiosis are diseases caused by opportunistic intracellular fungi in immunosuppressed individuals, as well as in transplanted patients, the elderly and children, among others. Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and decreased T cell response, neutrophil function, humoral immunity failure, increasing the susceptibility to infections. Here, we investigated the susceptibility of streptozotocin (STZ)-induced type I diabetic and/or immunosuppressed mice to encephalitozoonosis by Encephalitozoon cuniculi. Microscopically, granulomatous hepatitis, interstitial pneumonia and pielonephritis were observed in all infected groups. STZ treatment induced an immunossupressor effect in the populations of B (B-1 and B2) and CD4⁺ T lymphocytes. Moreover, infection decreased CD4⁺ and CD8⁺ T lymphocytes and macrophages of DM mice. Furthermore, infection induced a significant increase of IL-6 and TNF-α cytokine serum levels in DM mice. IFN-γ, the most important cytokine for the resolution of encephalitozoonosis, increased only in infected mice. In addition to the decreased immune response, DM mice were more susceptible to encephalitozoonosis, associated with increased fungal burden, and symptoms. Additionally, cyclophosphamide immunosuppression in DM mice further increased the susceptibility to encephalitozoonosis. Thus, microsporidiosis should be considered in the differential diagnosis of comorbidities in diabetics.

Diabetes and Sepsis: Risk, Recurrence, and Ruination

Sepsis develops when an infection surpasses local tissue containment. A series of dysregulated physiological responses are generated, leading to organ dysfunction and a 10% mortality risk. When patients with sepsis demonstrate elevated serum lactates and require vasopressor therapy to maintain adequate blood pressure in the absence of hypovolemia, they are in septic shock with an in-hospital mortality rate >40%. With improvements in intensive care treatment strategies, overall sepsis mortality has diminished to ~20% at 30 days; however, mortality continues to steadily climb after recovery from the acute event. Traditionally, it was thought that the complex interplay between inflammatory and anti-inflammatory responses led to sepsis-induced organ dysfunction and mortality. However, a closer examination of those who die long after sepsis subsides reveals that many initial survivors succumb to recurrent, nosocomial, and secondary infections. The comorbidly challenged, physiologically frail diabetic individuals suffer the highest infection rates. Recent reports suggest that even after clinical "recovery" from sepsis, persistent alterations in innate and adaptive immune responses exists resulting in chronic inflammation, immune suppression, and bacterial persistence. As sepsis-associated immune defects are associated with increased mortality long-term, a potential exists for immune modulatory therapy to improve patient outcomes. We propose that diabetes causes a functional immune deficiency that directly reduces immune cell function. As a result, patients display diminished bactericidal clearance, increased infectious complications, and protracted sepsis mortality. Considering the substantial expansion of the elderly and obese population, global adoption of a Western diet and lifestyle, and multidrug resistant bacterial emergence and persistence, diabetic mortality from sepsis is predicted to rise dramatically over the next two decades. A better understanding of the underlying diabetic-induced immune cell defects that persist following sepsis are crucial to identify potential therapeutic targets to bolster innate and adaptive immune function, prevent infectious complications, and provide more durable diabetic survival.

Defective production of interleukin-1 beta in patients with type 2 diabetes mellitus: Restoration by proper glycemic control

The underlying immune defect of susceptibility in diabetes mellitus type 2 to infections remains unknown. The qualitative changes in cytokine biosynthesis by circulating mononuclear cells (PBMCs) and its modulation by glycemic control were investigated. PBMCs were isolated from 39 patients and 25 controls. They were stimulated with purified ligands and heat-killed bacteria in the absence/presence of glucose and NLPR3 inflammasome ligands. Experiments were repeated after 3 and 6months. Cytokine production was measured in cell supernatants; pro-interleukin(IL)-1 β was measured in cell lysates. Gene expression of IL-1β and activity of caspase-1 were measured as well. Adequate release of interleukin (IL)-1β was found in 42.9% of patients compared to 90% of controls (p: 0.0001). This was related with down-regulation of the NLRP3 inflammasome since gene expression of IL-1β remained unaltered whereas both the ratio of IL-1β to the intracellular pro-IL-1β and the activity of caspase-1 was lower in patients than controls. Addition of glucose did not modify defective IL-1β production. IL-6 production was increased after stimulation with Pam3Cys, phytohemagglutinin and C. albicans. After proper glycemic control, release of IL-1β was increased and of IL-6 decreased; cells of patients with improved glycemic control responded better to LPS stimulation under increased concentrations of glucose. It is concluded that diabetes type 2 is characterized by defective production of IL-1β from circulating monocytes due to impaired activation of the NLRP3 inflammasome and increased production of the anti-inflammatory IL-6. Defects are restored with proper glycemic control.

IMMUNOLOGICAL EVALUATION OF PATIENTS WITH TYPE 2 DIABETES MELLITUS SUBMITTED TO METABOLIC SURGERY

BACKGROUND

Immunological and inflammatory mechanisms play a key role in the development and progression of type 2 diabetes mellitus.

AIM

To raise the hypothesis that alterations in immunological parameters occur after duodenojejunal bypass surgery combined with ileal interposition without gastrectomy, and influences the insulin metabolism of betacells.

METHODS

Seventeen patients with type 2 diabetes mellitus under clinical management were submitted to surgery and blood samples were collected before and six months after surgery for evaluation of the serum profile of proinflammatory (IFN-γ, TNF-α, IL-17A) and anti-inflammatory cytokines (IL-4, IL-10). In addition, anthropometric measures, glucose levels and insulin use were evaluated in each patient.

RESULTS

No changes in the expression pattern of proinflammatory cytokines were observed before and after surgery. In contrast, there was a significant decrease in IL-10 expression, which coincided with a reduction in the daily insulin dose, glycemic index, and BMI of the patients. Early presentation of food to the ileum may have induced the production of incretins such as GLP-1 and PYY which, together with glycemic control, contributed to weight loss, diabetes remission and the consequent good surgical prognosis of these patients. In addition, the control of metabolic syndrome was responsible for the reduction of IL-10 expression in these patients.

CONCLUSION

These findings suggest the presence of low-grade inflammation in these patients during the postoperative period, certainly as a result of adequate glycemic control and absence of obesity, contributing to a good outcome of surgery.

Association between IgE-mediated allergies and diabetes mellitus type 1 in children and adolescents

BACKGROUND

Type 1 diabetes mellitus (T1DM) is characterized by an immunological reaction that is dominated by type-1 T helper (Th1) cells, whereas immunoglobulin E (IgE)-mediated allergies are associated with Th2 cell. According to the Th1/Th2-hypothesis, the immune system is said to either develop into the direction of Th1 or Th2 cells. This would mean that a child developing T1DM is unlikely to develop an IgE-mediated allergy and vice versa.

OBJECTIVE

The aim of the study was to investigate the association between the prevalence of T1DM and IgE-mediated allergies.

METHODS

We designed a prospective case control study with 94 children and adolescents with T1DM and 188 age- and sex-matched control children. The basis of our investigations was a questionnaire concerning the family and children's history as to the presence of IgE-mediated allergies. Moreover, the following blood investigations were done: total serum IgE, specific IgE antibodies to major inhalant allergens, and a multiplex cytokine analysis measuring levels of specific cytokines representing either Th1- or Th2- cytokines.

RESULTS

Children with T1DM reported the presence of IgE-mediated allergies significantly more often than children of the control group. Children with T1DM had significantly higher tumor necrosis factor alpha (TNFα) levels than healthy controls. Levels of interleukin-2 (IL-2) and IL-6 were higher in the groups of children with the presence of a personal history of allergies, regardless of the presence of T1DM.

CONCLUSIONS

Our results suggest that T1DM is associated with a higher risk of a self-reported presence of IgE-mediated allergies and that the Th1/Th2-hypothesis may be an oversimplification.

Asymptomatic Bacteriuria in Noncatheterized Adults

Asymptomatic bacteriuria (ASB) is a common finding and frequently detected in premenopausal nonpregnant women, institutionalized patients, patients with diabetes mellitus, and the ambulatory elderly population. Despite clear recommendations regarding diagnosis and management of ASB in these populations from the Infectious Diseases Society of America (IDSA), there remains an alarming rate of antimicrobial overuse. This article reviews definitions of ASB, epidemiology of ASB, literature surrounding ASB in diabetic patients, risk factors of ASB, microbiologic data regarding bacterial virulence, use of ASB strains for treatment of symptomatic urinary tract infection, and approaches to addressing translational barriers to implementing IDSA recommendations regarding diagnosis and management of ASB.

Diabetes and the risk of infections with immunomodulator therapy in inflammatory bowel diseases

BACKGROUND

Infections are an important concern in patients using immunosuppressive therapy for their inflammatory bowel disease (IBD). Diabetes affects nearly 10% of Americans. Whether it confers an additional risk with immunosuppression in IBD has not been examined previously.

AIM

To examine the association between diabetes and infections with immunomodulator use in IBD METHODS: Using a validated, multi-institutional IBD cohort, we identified all patients who received at least one prescription for immunomodulators (thiopurines, methotrexate). Our primary outcome was infection within 1 year of the prescription of the immunomodulator. Multivariable logistic regression adjusting for relevant confounders was used to estimate the independent association with diabetes.

RESULTS

Our study included 2766 patients receiving at least one prescription for immunomodulators among whom 210 (8%) developed an infection within 1 year. Patients who developed an infection were likely to be older, have more comorbidities, more likely to have received a prescription for steroids but similar in initiation of anti-TNF therapy within that year. Only 8% of those without an infection had diabetes compared to 19% of those who developed an infection within 1 year [odds ratio (OR) 2.74, 95% confidence interval (CI) 1.88-3.98, P < 0.001]. On multivariate analysis, diabetes was independently associated with a nearly two-fold increase in risk of infections (OR: 1.80, 95% CI: 1.20-2.68). There was no increase in risk of infections with addition of anti-TNF therapy (OR: 1.14, 95% CI: 0.80-1.63).

CONCLUSION

Diabetes is an independent risk factor for infection in IBD patients using immunomodulator therapy.

Immunological mechanisms contributing to the double burden of diabetes and intracellular bacterial infections

Diabetes has been recognized as an important risk factor for a variety of intracellular bacterial infections, but research into the dysregulated immune mechanisms contributing to the impaired host-pathogen interactions is in its infancy. Diabetes is characterized by a chronic state of low-grade inflammation due to activation of pro-inflammatory mediators and increased formation of advanced glycation end products. Increased oxidative stress also exacerbates the chronic inflammatory processes observed in diabetes. The reduced phagocytic and antibacterial activity of neutrophils and macrophages provides an intracellular niche for the pathogen to replicate. Phagocytic and antibacterial dysfunction may be mediated directly through altered glucose metabolism and oxidative stress. Furthermore, impaired activation of natural killer cells contributes to decreased levels of interferon-γ, required for promoting macrophage antibacterial mechanisms. Together with impaired dendritic cell function, this impedes timely activation of adaptive immune responses. Increased intracellular oxidation of antigen-presenting cells in individuals with diabetes alters the cytokine profile generated and the subsequent balance of T-cell immunity. The establishment of acute intracellular bacterial infections in the diabetic host is associated with impaired T-cell-mediated immune responses. Concomitant to the greater intracellular bacterial burden and potential cumulative effect of chronic inflammatory processes, late hyper-inflammatory cytokine responses are often observed in individuals with diabetes, contributing to systemic pathology. The convergence of intracellular bacterial infections and diabetes poses new challenges for immunologists, providing the impetus for multidisciplinary research.

Urinary tract infections in patients with type 2 diabetes mellitus: review of prevalence, diagnosis, and management

Urinary tract infections are more common, more severe, and carry worse outcomes in patients with type 2 diabetes mellitus. They are also more often caused by resistant pathogens. Various impairments in the immune system, poor metabolic control, and incomplete bladder emptying due to autonomic neuropathy may all contribute to the enhanced risk of urinary tract infections in these patients. The new anti-diabetic sodium glucose cotransporter 2 inhibitors have not been found to significantly increase the risk of symptomatic urinary tract infections. Symptoms of urinary tract infection are similar to patients without diabetes, though some patients with diabetic neuropathy may have altered clinical signs. Treatment depends on several factors, including: presence of symptoms, severity of systemic symptoms, if infection is localized in the bladder or also involves the kidney, presence of urologic abnormalities, accompanying metabolic alterations, and renal function. There is no indication to treat diabetic patients with asymptomatic bacteriuria. Further studies are needed to improve the treatment of patients with type 2 diabetes and urinary tract infections.

Impact of training status on LPS-induced acute inflammation in humans

The aim of the present study was to examine the impact of training status on the ability to induce a lipopolysaccharide (LPS)-induced inflammatory response systemically as well as in skeletal muscle (SkM) and adipose tissue (AT) in human subjects. Seventeen young (23.8 ± 2.5 yr of age) healthy male subjects were included in the study with eight subjects assigned to a trained (T) group and nine subjects assigned to an untrained (UT) group. On the experimental day, catheters were inserted in the femoral artery and vein of one leg for blood sampling and a bolus of 0.3 ng LPS/kg body wt was injected into an antecubital vein in the forearm. Femoral arterial blood flow was measured by ultrasound Doppler, and arterial and venous blood samples were drawn before (Pre) LPS injection and 30, 60, 90, and 120 min after the LPS injection. Vastus lateralis muscle and abdominal subcutaneous AT biopsies were obtained Pre and 60 and 120 min after the LPS injection. LPS increased the systemic plasma TNFα and IL-6 level as well as the TNFα and IL-6 mRNA content in SkM and AT of both UT and T. However, whereas the LPS-induced inflammatory response in SkM was enhanced in T subjects relative to UT, the inflammatory response systemically and in AT was somewhat delayed in T subjects relative to UT. The present findings highlight that training status affects the ability to induce a LPS-induced acute inflammatory response in a tissue-specific manner.

Vitamin D deficiency is associated with inflammatory cytokine concentrations in patients with diabetic foot infection

Vitamin D has been recognised as a potent immunomodulator and its deficiency is common in different population groups including patients with diabetic foot infection. Diabetic foot infection reflects the altered immune status of the host. As cytokine regulation plays a significant role in infection and wound-healing processes, the present study aimed to evaluate the association between vitamin D status and inflammatory cytokine profiles in patients with diabetic foot infection. The serum concentrations of vitamin D (25-hydroxyvitamin D), IL-1β, IL-6, TNF-α and interferon-γ (IFN-γ) were measured in 112 diabetic foot infection cases and 109 diabetic controls. Severe vitamin D deficiency (25-hydroxyvitamin D concentration < 25 nmol/l) was more common in cases than in controls (48·2v.20·5 %). Although age, duration of diabetes, HbA1C(glycosylated Hb) concentration and BMI were similar, cases had significantly higher concentrations of IL-6 (P≤ 0·001), IL-1β (P≤ 0·02) and TNF-α (P≤ 0·006) than controls. A significant negative correlation was also observed between 25-hydroxyvitamin D concentration and circulating concentrations of IL-1β (r− 0·323;P≤ 0·001) as well as IL-6 (r− 0·154;P≤ 0·04), but not between 25-hydroxyvitamin D and TNF-α and IFN-γ concentrations. Furthermore, a significant difference in IL-1β (P≤ 0·007) and IL-6 (P≤ 0·02) concentrations was observed in patients with severe 25-hydroxyvitamin D deficiency compared with patients with 25-hydroxyvitamin D concentration ≥ 25 nmol/l, and this difference was remarkable for TNF-α. In conclusion, severe vitamin D deficiency is associated with elevated inflammatory cytokine concentrations in diabetic patients, particularly in those with foot infection. A 25-hydroxyvitamin D concentration value < 25 nmol/l is suggested as the ‘cut-off’ for such immunological alterations in patients with diabetes mellitus.

Genital and urinary tract infections in diabetes: impact of pharmacologically-induced glucosuria

Predisposition to genital infections and urinary tract infections (UTIs) in type 2 diabetes mellitus (T2DM) results from several factors such as glucosuria, adherence of bacteria to the uroepithelium and immune dysfunction. The tendency to develop these infections could be even higher in patients with T2DM treated with the emerging class of sodium-glucose cotransporter-2 (SGLT2) inhibitors. Studies have shown that pharmacologically-induced glucosuria with SGLT2 inhibitors raises the risk of developing genital infections and, to a relatively lesser extent, UTIs. However, a definitive dose relationship of the incidence of these infections with the SGLT2 doses is not evident in the existing data. Therefore, the precise role of glucosuria as a causative factor for these infections is yet to be fully elucidated.

Inhibition of increased circulating Tfh cell by anti-CD20 monoclonal antibody in patients with type 1 diabetes

Objectives

Follicular helper T (Tfh) cells exert an important role in autoimmune diseases. Whether it might be involved in type 1 diabetes (T1D) is unknown. Our aim was to investigate the role of Tfh cells in patients with T1D and the effect of anti-CD20 monoclonal antibody (rituximab) on Tfh cells from T1D patients.

Patients and Methods

Fifty-four patients with T1D and 37 healthy controls were enrolled in the current study. 20 of those patients were treated with rituximab. The frequencies of circulating CD4⁺CXCR5⁺ICOS⁺T cells were analyzed by flow cytometry. The serum autoantibodies were detected by radioligand assay. The levels of IL-21, IL-6 and BCL-6 were assessed using ELISA and/or real-time PCR.

Results

Increased frequencies of circulating Tfh cells together with enhanced expression of IL-21 were detected in patients. The correlation between the frequencies of circulating Tfh cells and the serum autoantibodies or C-peptide level was comfirmed. After rituximab therapy, follow-up analysis demonstrated that the frequencies of circulating Tfh cell and serum IA2A were decreased. The levels of IL-21, IL-6 and Bcl-6 mRNA were decreased after treatment. Furthermore, beta cell function in 10 of 20 patients was improved.

Conclusions

These data indicate Tfh cells may participate in the T1D-relatede immune responses and B cells might play a role in the development of Tfh responses in the disease progression.

Upregulation of proinflammatory cytokine production in response to bacterial pathogen-associated molecular patterns in dogs with diabetes mellitus undergoing insulin therapy

BACKGROUND

Metabolic alterations associated with diabetes mellitus alter innate immunity. Dogs often develop infectious or inflammatory complications related to diabetes mellitus, yet little is known about the effects of diabetes mellitus on the immune system in this species.

METHODS

Prospective evaluation in dogs with poorly regulated spontaneous type 1 diabetes mellitus (T1DM). In vitro leukocyte cytokine response to lipopolysaccharide (LPS), lipoteichoic acid (LTA), and peptidoglycan (PG) was compared between dogs with T1DM and healthy dogs. Additionally, the effect of acute in vitro glucose exposure on leukocyte tumor necrosis factor (TNF) production from healthy dogs was measured.

RESULTS

Leukocytes from dogs with T1DM had significantly greater TNF production after LTA and PG stimulation compared with leukocytes from healthy dogs. Leukocyte interleukin (IL)-6 production was greater after stimulation with LPS, LTA, PG, and phosphate-buffered saline in the T1DM group. No such difference was noted when evaluating IL-10 production between groups regardless of stimulant. Dogs with T1DM had significantly greater IL-6 to IL-10 production ratios than healthy dogs. Acute exposure to dextrose did not augment cytokine production from healthy canine leukocytes.

CONCLUSIONS

Dogs with T1DM have altered innate immunity characterized by upregulation of proinflammatory cytokine production without a concurrent change in anti-inflammatory cytokine production. This may be one explanation for the common infectious and inflammatory complications associated with T1DM in dogs.

Infections in patients with diabetes mellitus: A review of pathogenesis

In general, infectious diseases are more frequent and/or serious in patients with diabetes mellitus, which potentially increases their morbimortality. The greater frequency of infections in diabetic patients is caused by the hyperglycemic environment that favors immune dysfunction (e.g., damage to the neutrophil function, depression of the antioxidant system, and humoral immunity), micro- and macro-angiopathies, neuropathy, decrease in the antibacterial activity of urine, gastrointestinal and urinary dysmotility, and greater number of medical interventions in these patients. The infections affect all organs and systems. Some of these problems are seen mostly in diabetic people, such as foot infections, malignant external otitis, rhinocerebral mucormycosis, and gangrenous cholecystitis. In addition to the increased morbidity, infectious processes may be the first manifestation of diabetes mellitus or the precipitating factors for complications inherent to the disease, such as diabetic ketoacidosis and hypoglycemia. Immunization with anti-pneumococcal and influenza vaccines is recommended to reduce hospitalizations, deaths, and medical expenses.

Anticoagulatory and antiinflammatory effects of astaxanthin in diabetic rats

Astaxanthin at 0.01 or 0.05% of the diet was supplied to diabetic rats for 12 wk. Astaxanthin intake significantly increased its deposit in plasma, and retained glutathione content, reduced the production of reactive oxygen species, interleukin-6, tumor necrosis factor-α, and monocyte chemoattractant protein-1 in blood and kidney of diabetic rats (P < 0.05). Astaxanthin treatments also significantly decreased plasma levels of C-reactive protein and von Willebrand factor in diabetic rats (P < 0.05). Astaxanthin intake at 0.05% significantly diminished plasminogen activator inhibitor-1 and factor VII activities, enhanced antithrombin-III and protein C activities in circulation (P < 0.05). These results support that astaxanthin could attenuate diabetes associated coagulatory, oxidative, and inflammatory stress.