Elevated proinflammatory cytokine production by a skewed T cell compartment requires monocytes and promotes inflammation in type 2 diabetes

Regulation of Immune Cell Function by Nicotinamide Nucleotide Transhydrogenase

Redox homeostasis is elemental for the normal physiology of all cell types. Cells use multiple mechanisms to regulate the redox balance tightly. The onset and progression of many metabolic and aging-associated diseases occur due to the dysregulation of redox homeostasis. Thus, it is critical to identify and therapeutically target mechanisms that precipitate abnormalities in redox balance. Reactive oxygen species (ROS) produced within the immune cells regulate homeostasis, hyperimmune and hypoimmune cell responsiveness, apoptosis, immune response to pathogens, and tumor immunity. Immune cells have both cytosolic and organelle-specific redox regulatory systems to maintain appropriate levels of ROS. Nicotinamide nucleotide transhydrogenase (NNT) is an essential mitochondrial redox regulatory protein. Dysregulation of NNT function prevents immune cells from mounting an adequate immune response to pathogens, promotes a chronic inflammatory state associated with aging and metabolic diseases, and initiates conditions related to a dysregulated immune system such as autoimmunity. While many studies have reported on NNT in different cell types, including cancer cells, relatively few studies have explored NNT in immune cells. This review provides an overview of NNT and focuses on the current knowledge of NNT in the immune cells.

Regulatory T Cells Control Effector T Cell Inflammation in Human Prediabetes

A disparate array of plasma/serum markers provides evidence for chronic inflammation in human prediabetes, a condition that is most closely replicated by standard mouse models of obesity and metaflammation. These remain largely nonactionable and contrast with our rich understanding of inflammation in human type 2 diabetes. New data show that inflammatory profiles produced by CD4+ T cells define human prediabetes as a unique inflammatory state. Regulatory T cells (Treg) control mitochondrial function and cytokine production by CD4+ effector T cells (Teff) in prediabetes and type 2 diabetes by supporting T helper (Th)17 or Th1 cytokine production, respectively. These data suggest that Treg control of Teff metabolism regulates inflammation differentially in prediabetes compared with type 2 diabetes. Queries of genes that impact mitochondrial function or pathways leading to transcription of lipid metabolism genes identified the fatty acid importer CD36 as highly expressed in Treg but not Teff from subjects with prediabetes. Pharmacological blockade of CD36 in Treg from subjects with prediabetes decreased Teff production of the Th17 cytokines that differentiate overall prediabetes inflammation. We conclude that Treg control CD4+ T cell cytokine profiles through mechanisms determined, at least in part, by host metabolic status. Furthermore, Treg CD36 uniquely promotes Th17 cytokine production by Teff in prediabetes.

Interplay Among the Oral Microbiome, Oral Cavity Conditions, the Host Immune Response, Diabetes Mellitus, and Its Associated-Risk Factors-An Overview

This comprehensive review of the literature aimed to investigate the interplay between the oral microbiome, oral cavity conditions, and host immune response in Diabetes mellitus (DM). Moreover, this review also aimed to investigate how DM related risk factors, such as advanced age, hyperglycemia, hyperlipidemia, obesity, hypertension and polycystic ovary syndrome (PCOS), act in promoting or modifying specific mechanisms that could potentially perpetuate both altered systemic and oral conditions. We found that poorly controlled glycemic index may exert a negative effect on the immune system of affected individuals, leading to a deficient immune response or to an exacerbation of the inflammatory response exacerbating DM-related complications. Hyperglycemia induces alterations in the oral microbiome since poor glycemic control is associated with increased levels and frequencies of periodontal pathogens in the subgingival biofilm of individuals with DM. A bidirectional relationship between periodontal diseases and DM has been suggested: DM patients may have an exaggerated inflammatory response, poor repair and bone resorption that aggravates periodontal disease whereas the increased levels of systemic pro-inflammatory mediators found in individuals affected with periodontal disease exacerbates insulin resistance. SARS-CoV-2 infection may represent an aggravating factor for individuals with DM. Individuals with DM tend to have low salivary flow and a high prevalence of xerostomia, but the association between prevalence/experience of dental caries and DM is still unclear. DM has also been associated to the development of lesions in the oral mucosa, especially potentially malignant ones and those associated with fungal infections. Obesity plays an important role in the induction and progression of DM. Co-affected obese and DM individuals tend to present worse oral health conditions. A decrease in HDL and, an increase in triglycerides bloodstream levels seem to be associated with an increase on the load of periodontopathogens on oral cavity. Moreover, DM may increase the likelihood of halitosis. Prevalence of impaired taste perception and impaired smell recognition tend to be greater in DM patients. An important interplay among oral cavity microbiome, DM, obesity and hypertension has been proposed as the reduction of nitrate into nitrite, in addition to contribute to lowering of blood pressure, reduces oxidative stress and increases insulin secretion, being these effects desirable for the control of obesity and DM. Women with PCOS tend to present a distinct oral microbial composition and an elevated systemic response to selective members of this microbial community, but the association between oral microbiome, PCOS are DM is still unknown. The results of the studies presented in this review suggest the interplay among the oral microbiome, oral cavity conditions, host immune response and DM and some of the DM associated risk factors exist. DM individuals need to be encouraged and motivated for an adequate oral health care. In addition, these results show the importance of adopting multidisciplinary management of DM and of strengthening physicians-dentists relationship focusing on both systemic and on oral cavity conditions of DM patients.

Influence of antipsychotics on metabolic syndrome risk in patients with schizophrenia

OBJECTIVE

Many studies so far have shown that antipsychotic therapy may have an effect on the development of metabolic syndrome in patients diagnosed with schizophrenia. Our goal was to determine whether our respondents are at risk for developing metabolic syndrome and who is more predisposed to it.

METHODS

In a stable phase, 60 patients diagnosed with schizophrenia were equally divided into three groups according to the drug (risperidone, clozapine, and aripiprazole monotherapy). Control group had 20 healthy examinees. Patients were evaluated first using The Positive and Negative Syndrome Scale (PANSS). Prolactin, lipid status, glycemia, insulin, cytokine values (IL-33, TGF-β, and TNF-α) and C-reactive protein (CRP) were measured. Also, Body mass index (BMI), Homeostatic Model Assesment for Insulin Resistance (HOMA index), waist and hip circumference (WHR) and blood pressure (TA) measurement were performed in the study.

RESULTS

Patients treated with risperidone compared to healthy control subjects and aripiprazol group of patients had statistically significant difference in prolactin levels. In clozapine group compared to healthy control group values of HDL cholesterol and glucose level were statistically significant different. In aripiprazole group compared to healthy control group value of BMI was statistically significant different. Statistically significant correlations were found in TNF-α with glucose and HOMA index in risperidone treated patients and with BMI in clozapine group of patients; IL-33 with glucose in risperidone and with BMI in clozapine group of patients and TGF-β with glucose in risperidone group, with insulin and HOMA index in clozapine group and statistically significant negative correlation with LDL cholesterol in aripiprazole group of patients.

CONCLUSION

Patients on risperidone and clozapine therapy may be at greater risk of developing metabolic syndrome than patients treated with aripiprazole. Statistically significant difference in concentration of TNF-α and TGF-β was in the group of patients treated with risperidone compared to healthy control group.

Changes of Peripheral Th17 Cells Subset in Overweight and Obese Children After Body Weight Reduction

BACKGROUND

Obesity has been a growing problem in young patients leading to serious metabolic complications. There are many studies supporting the idea, that obesity should be considered as a chronic inflammation closely associated with immune system alterations. Th17 subpopulation is strongly involved in this process. The aim of our study was to evaluate circulating Th17 cells in overweight and obese children and explore the relationships between Th17 subset and metabolic parameters.

METHODS

We evaluated peripheral Th17 cells in fresh peripheral blood samples from 27 overweight and obese and 15 normal-weight children. Th17 cells were identified by flow cytometry using monoclonal antibody and intracellular IL-17A staining. Th17 cells were defined as CD3⁺CD4⁺CD196⁺IL-17A^ic+. The analysis involved anthropometric and metabolic parameters measured at baseline and three months after the change of lifestyle and diet. We evaluated the relationship between metabolic parameters and Th17 cells.

RESULTS

In overweight and obese children we found significantly higher Th17 cells percentage compared to normal weight controls (median 0.097% (0.044 - 0.289) vs 0.041% (0.023 - 0.099), p = 0.048). The percentage of Th17 cells decreased statistically significantly in children who reduced weight after the intervention (0.210% (0.143 - 0.315) vs 0.039% (0.028 - 0.106), p = 0.004). In this group we also noticed statistically significant reduction of TC and LDL-C concentration (p = 0.01, p = 0.04, respectively).

CONCLUSIONS

Obesity in children is associated with increased percentage of peripheral Th17 cells. Weight reduction leads to significant decrease of circulating Th17 cells and improvement of lipid parameters. This significant reduction of proinflammatory Th17 cells is a promising finding suggesting that obesity-induced inflammation in children could be relatively easily reversible.

Adaptive immune cells shape obesity-associated type 2 diabetes mellitus and less prominent comorbidities

Obesity and type 2 diabetes mellitus (T2DM) are increasing in prevalence owing to decreases in physical activity levels and a shift to diets that include addictive and/or high-calorie foods. These changes are associated with the adoption of modern lifestyles and the presence of an obesogenic environment, which have resulted in alterations to metabolism, adaptive immunity and endocrine regulation. The size and quality of adipose tissue depots in obesity, including the adipose tissue immune compartment, are critical determinants of overall health. In obesity, chronic low-grade inflammation can occur in adipose tissue that can progress to systemic inflammation; this inflammation contributes to the development of insulin resistance, T2DM and other comorbidities. An improved understanding of adaptive immune cell dysregulation that occurs during obesity and its associated metabolic comorbidities, with an appreciation of sex differences, will be critical for repurposing or developing immunomodulatory therapies to treat obesity and/or T2DM-associated inflammation. This Review critically discusses how activation and metabolic reprogramming of lymphocytes, that is, T cells and B cells, triggers the onset, development and progression of obesity and T2DM. We also consider the role of immunity in under-appreciated comorbidities of obesity and/or T2DM, such as oral cavity inflammation, neuroinflammation in Alzheimer disease and gut microbiome dysbiosis. Finally, we discuss previous clinical trials of anti-inflammatory medications in T2DM and consider the path forward.

Apical periodontitis promotes insulin resistance and alters adaptive immunity markers in rats

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Periapical lesions promotes higher T-bet expression and lower GATA3 and FOXP3 expression.

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Periapical lesion promotes increased GATA3 and decreased FOXP3 expression in the group with 4 periapical lesions (4PL)

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The adaptive immune system, with a predominance of the Th1 polarization, may be involved in the development of insulin resistance in rats with Periapical lesions.

Objective

Apical periodontitis (AP) is a chronic or acute inflammatory disease usually developed from endodontic infections, predominantly due to gram-negative anaerobic bacteria invading the dental pulp. This study aimed to evaluate lymphocyte markers to assess the involvement of adaptive immunity in insulin resistance (IR) in a rat model of AP.

Design.

Forty-five male Wistar albino rats were divided into 3 groups (control, 1AP and 4AP). AP was induced in the upper right first molar (1AP), and in the first and second upper and lower right molars (4AP). The spleen was collected to evaluate the expression of transcription factors involved in lymphocyte polarization, including T-bet (Th1), GATA3 (Th2), and FOXP3 (Treg). Blood samples were assessed for serum cytokine levels transcribed by the respective lymphocyte polarizations, INF-γ (Th1), IL-4 (Th2) and TGF-β (Treg). In addition, glucose and insulin levels were measured to evaluate IR by the HOMA-IR method.

Results

The results showed higher T-bet expression on AP groups, along with lower GATA3 and FOXP3 expression in the 1AP, in addition to increased GATA3 and decreased FOXP3 expression in the 4AP group compared to the CN group. There was no difference in the INF-γ levels, while IL-4 was decreased in the AP groups. Taken together, these results suggest that the adaptive immune system, with a predominance of the Th1 polarization, may be involved in the development of IR in rats with AP.

Conclusions

AP promotes increase in the expression of T-bet (4AP) and decrease of FOXP3 expressions and IL-4 levels (1AP and 4AP). However, depending on the number of lesions (1 or 4 lesions), the expression of GATA3 appears differently. Thus, innate immunity and adaptive immunity may contribute to the IR observed in rats with AP.

Type and Intensity as Key Variable of Exercise in Metainflammation diseases: A Review

Monocyte and lymphocyte subpopulations exhibit functions that vary between the anti- and pro-inflammatory spectrum, such as classic CD16- and non-classical CD16+ monocytes, as well as T helper 2 lymphocytes (Th2), the Th1/Th17 lymphocytes ratio, and T regulatory lymphocytes (Treg). Metabolic disease-associated inflammation is accompanied by an imbalance in monocyte and lymphocyte phenotypes and functionality, as well as a stronger proportion of inflammatory subpopulations. These changes appear to be important for the development and progression of diseases like diabetes and cardiovascular disease. On the other hand, the regular practice of physical exercise is an important tool to restore the functionality of monocytes and lymphocytes, and to balance the subtypes ratio. However, key variables regarding exercise prescription, such as the type of exercise, intensity, and volume differentially impact on the acute and chronic immune response in individuals diagnosed with meta inflammation diseases. Here, we discuss the impact of different physical exercise protocols, acutely and chronically, on monocytes and lymphocytes of individuals with metabolic disease-associated inflammation. In this review, we focus on the best effects of different exercise protocols to dose the "exercise pill" in different inflammatory status.

Diabetes in COVID-19 patients: challenges and possible management strategies

Background

The recent pandemic of coronavirus disease 19 (COVID-19) has been causing intense stress among the global population. In the case of hospitalized and ICU-admitted COVID-19 patients with comorbidities, it has been observed that a major portion of them are diabetic. Therefore, researchers had indicated a link between diabetes mellitus (DM) and COVID-19. Furthermore, DM is a potential risk factor for the severity of COVID-19 cases. Thus, in this study, the correlation existing between diabetic patients and COVID-19 was summarized.

Main body of the abstract

Diabetic patients have a weaker immune system, less viral clearance rate, malfunctions of metabolic activity due to their high blood glucose level, and other associated problems. This does not increase the susceptibility for the patients to be infected with COVID-19. However, the severity of COVID-19 can worsen due to the comorbidity of DM.

Short conclusion

Proper management, appropriate use of drugs that do not increase the ACE2 expression, lowering blood glucose level, decreasing the susceptibility of SARS-CoV-2, and maintaining a healthy lifestyle could be effective.

Nitazoxanide Exerts Immunomodulatory Effects on Peripheral Blood Mononuclear Cells from Type 2 Diabetes Patients

BACKGROUND

Type 2 diabetes (T2D) is a low-grade inflammatory condition with abnormalities in the immune response mediated by T lymphocytes and macrophages. Drug repositioning for immunomodulatory molecules is an attractive proposal for treating T2D. Nitazoxanide (NTZ) is a broad-spectrum drug with promising immunomodulatory effects. Thus, we investigated the immunomodulatory effect of NTZ on peripheral blood mononuclear cells (PBMCs) from patients with T2D.

METHODS

Fifty patients with T2D were selected, and the proliferative response of T lymphocytes and the M1/M2 ratio of macrophages post cell culture were evaluated by flow cytometry, as well as measuring the concentration of cytokines by ELISA and the relative expression of microRNAs (miRNAs) related to the immune response by real-time PCR.

RESULTS

NTZ exerts an inhibitory effect on the cell proliferation of T lymphocytes stimulated with anti-CD3 and anti-CD28 antibodies without modifying cell viability, and significant decreases in the supernatant concentrations of interleukin (IL)-1β, IL-2, IL-6, IL-10, and IL-12. Furthermore, NTZ negatively regulates the relative expression of miR-155-5p without changes in miR-146a-5p. The M1/M2 ratio of monocytes/macrophages decreased the M1 and increased the M2 subpopulation by NTZ.

CONCLUSIONS

Our results suggest that NTZ exerts immunomodulatory effects on PBMCs from T2D patients, and shows potential alternative therapeutic benefits.

Leukocyte Counts and T-Cell Frequencies Differ Between Novel Subgroups of Diabetes and Are Associated With Metabolic Parameters and Biomarkers of Inflammation

Frequencies of circulating immune cells are altered in those with type 1 and type 2 diabetes compared with healthy individuals and are associated with insulin sensitivity, glycemic control, and lipid levels. This study aimed to determine whether specific immune cell types are associated with novel diabetes subgroups. We analyzed automated white blood cell counts (n = 669) and flow cytometric data (n = 201) of participants in the German Diabetes Study with recent-onset (<1 year) diabetes, who were allocated to five subgroups based on data-driven analysis of clinical variables. Leukocyte numbers were highest in severe insulin-resistant diabetes (SIRD) and mild obesity-related diabetes (MOD) and lowest in severe autoimmune diabetes (SAID). CD4⁺ T-cell frequencies were higher in SIRD versus SAID, MOD, and mild age-related diabetes (MARD), and frequencies of CCR4⁺ regulatory T cells were higher in SIRD versus SAID and MOD and in MARD versus SAID. Pairwise differences between subgroups were partially explained by differences in clustering variables. Frequencies of CD4⁺ T cells were positively associated with age, BMI, HOMA2 estimate of β-cell function (HOMA2-B), and HOMA2 estimate of insulin resistance (HOMA2-IR), and frequencies of CCR4⁺ regulatory T cells with age, HOMA2-B, and HOMA2-IR. In conclusion, different leukocyte profiles exist between novel diabetes subgroups and suggest distinct inflammatory processes in these diabetes subgroups.

Inflammation in Metabolic Cardiomyopathy

Overlapping pandemics of lifestyle-related diseases pose a substantial threat to cardiovascular health. Apart from coronary artery disease, metabolic disturbances linked to obesity, insulin resistance and diabetes directly compromise myocardial structure and function through independent and shared mechanisms heavily involving inflammatory signals. Accumulating evidence indicates that metabolic dysregulation causes systemic inflammation, which in turn aggravates cardiovascular disease. Indeed, elevated systemic levels of pro-inflammatory cytokines and metabolic substrates induce an inflammatory state in different cardiac cells and lead to subcellular alterations thereby promoting maladaptive myocardial remodeling. At the cellular level, inflammation-induced oxidative stress, mitochondrial dysfunction, impaired calcium handling, and lipotoxicity contribute to cardiomyocyte hypertrophy and dysfunction, extracellular matrix accumulation and microvascular disease. In cardiometabolic patients, myocardial inflammation is maintained by innate immune cell activation mediated by pattern recognition receptors such as Toll-like receptor 4 (TLR4) and downstream activation of the NLRP3 inflammasome and NF-κB-dependent pathways. Chronic low-grade inflammation progressively alters metabolic processes in the heart, leading to a metabolic cardiomyopathy (MC) phenotype and eventually to heart failure with preserved ejection fraction (HFpEF). In accordance with preclinical data, observational studies consistently showed increased inflammatory markers and cardiometabolic features in patients with HFpEF. Future treatment approaches of MC may target inflammatory mediators as they are closely intertwined with cardiac nutrient metabolism. Here, we review current evidence on inflammatory processes involved in the development of MC and provide an overview of nutrient and cytokine-driven pro-inflammatory effects stratified by cell type.

The impact of the Th17:Treg axis on the IgA-Biome across the glycemic spectrum

Secretory IgA (SIgA) is released into mucosal surfaces where its function extends beyond that of host defense to include the shaping of resident microbial communities by mediating exclusion/inclusion of respective microbes and regulating bacterial gene expression. In this capacity, SIgA acts as the fulcrum on which host immunity and the health of the microbiota are balanced. We recently completed an analysis of the gut and salivary IgA-Biomes (16S rDNA sequencing of SIgA-coated/uncoated bacteria) in Mexican-American adults that identified IgA-Biome differences across the glycemic spectrum. As Th17:Treg ratio imbalances are associated with gut microbiome dysbiosis and chronic inflammatory conditions such as type 2 diabetes, the present study extends our prior work by examining the impact of Th17:Treg ratios (pro-inflammatory:anti-inflammatory T-cell ratios) and the SIgA response (Th17:Treg-SIgA axis) in shaping microbial communities. Examining the impact of Th17:Treg ratios (determined by epigenetic qPCR lymphocyte subset quantification) on the IgA-Biome across diabetes phenotypes identified a proportional relationship between Th17:Treg ratios and alpha diversity in the stool IgA-Biome of those with dysglycemia, significant changes in community composition of the stool and salivary microbiomes across glycemic profiles, and genera preferentially abundant by T-cell inflammatory phenotype. This is the first study to associate epigenetically quantified Th17:Treg ratios with both the larger and SIgA-fractionated microbiome, assess these associations in the context of a chronic inflammatory disease, and offers a novel frame through which to evaluate mucosal microbiomes in the context of host responses and inflammation.

Circulating

Impaired Glc tolerance and hyperinsulinemia are a hallmark of type 2 diabetes (T2D) and are associated with an altered innate and adaptive immune response. In this study, we used a high-fat diet (HFD)-induced model of pre-diabetes to explore the pathological implications of altered innate lymphoid cell (ILC) profiles in a state of impaired Glc tolerance. Sixteen male C57BL/6 mice were randomized to receive two experimental diets (n = 8 per group), low-fat (LFD), and HFD for 8-13 wk. We evaluated the levels of circulating innate lymphoid cells and their respective cytokines following HFD-feeding. The HFD group had impaired Glc tolerance, elevated insulin levels, and increased total cholesterol levels. Notably, the levels of circulating ILC1s were elevated following 13 wk of HFD-feeding. Moreover, the levels of TNF-α were decreased, but there were no changes in IFN-γ levels. Lastly, the levels of circulating ILC2s and ILC3s were comparable between the HFD and LFD group. The findings demonstrated that short-term HFD-feeding increases postprandial blood Glc, total cholesterol and insulin levels. However, the metabolic changes did not alter ILC2 and ILC3 levels and their respective cytokine profiles.

Is diabetes mellitus a wrongdoer to COVID-19 severity?

The coronavirus disease 19 (COVID-19) has turned out to be a pandemic in short period of time due to the high transmissibility of its causative agent, severe acute respiratory syndrome coronavirus 2. Various reports have suggested the promising link between overexpression of angiotensin converting enzyme 2 (ACE2) and COVID-19 pathogenesis. The severity of COVID-19 pathophysiology is greatly depended on several comorbidities, like hypertension, diabetes mellitus (DM), respiratory and cardiovascular disease, out of which DM has emerged as a major risk factor. The current review focuses on the link among the expression of ACE2, use of ACE inhibitors (ACEIs) and angiotensin II type 1 receptor blockers (ARBs), and risk of COVID-19 pathogenesis in DM. The review also emphasizes on synergistic detrimental effect of DM and COVID-19 on the immune system in provoking uncontrolled cytokine storm which eventually leads to lethal consequences. Finally, several possible therapeutic strategies have been highlighted to reduce the excess of risk associated with COVID-19 in people with DM.

The Alterations in and the Role of the Th17/Treg Balance in Metabolic Diseases

Chronic inflammation plays an important role in the development of metabolic diseases. These include obesity, type 2 diabetes mellitus, and metabolic dysfunction-associated fatty liver disease. The proinflammatory environment maintained by the innate immunity, including macrophages and related cytokines, can be influenced by adaptive immunity. The function of T helper 17 (Th17) and regulatory T (Treg) cells in this process has attracted attention. The Th17/Treg balance is regulated by inflammatory cytokines and various metabolic factors, including those associated with cellular energy metabolism. The possible underlying mechanisms include metabolism-related signaling pathways and epigenetic regulation. Several studies conducted on human and animal models have shown marked differences in and the important roles of Th17/Treg in chronic inflammation associated with obesity and metabolic diseases. Moreover, Th17/Treg seems to be a bridge linking the gut microbiota to host metabolic disorders. In this review, we have provided an overview of the alterations in and the functions of the Th17/Treg balance in metabolic diseases and its role in regulating immune response-related glucose and lipid metabolism.

Association between sarcoidosis and diabetes mellitus: a systematic review and meta-analysis

Background: Sarcoidosis is multisystem inflammatory granulomatosis that can potentially affect any organ of the human body. We aimed to estimate the prevalence of diabetes mellitus (DM) in sarcoidosis patients and determine the association between sarcoidosis and DM.Method: All relevant articles reporting the prevalence of DM in sarcoidosis published until September 19^th, 2020, were retrieved from ten electronic databases. We used the random effect model to perform the meta-analysis.Results: After screening 2,122 records, we included 19 studies (n = 18,686,162). The prevalence of DM in sarcoidosis patients was 12.7% (95% CI 10-16.1). The prevalence was highest in North America with 21.3% (13.5-31.8), followed by Europe 10.4 (7.9-13.7) and Asia 10% (1.8-39.7). Sarcoidosis patients had higher rates of DM compared to controls (OR 1.75; 95% CI 1.49-2.05). Sensitivity analysis, after removing the largest weighted study, did not reveal any effect on the significance of the results (OR 1.73; 95% CI 1.33-2.25).Conclusion: The prevalence of DM in sarcoidosis is considerably high, with increased odds of DM in sarcoidosis compared to healthy controls. Further research with a wide range of confounders is required to confirm the association of sarcoidosis with DM.

Regulatory T Cells and Diabetes Mellitus

Immune system dysfunction causes dysregulation of immune homeostasis, which in turn leads to autoimmune diseases. Regulatory T cells (Tregs) are a specialized T cell subpopulation that maintain peripheral tolerance and immune homeostasis. Diabetic patients are at an increased risk of developing cardiovascular diseases; thus, in terms of coronary risk, diabetes mellitus (DM) is considered coronary heart disease equivalent. Accumulating evidence indicates that Tregs play an important role in protecting against the development of various cardiovascular diseases. In this review, we provide an overview of the role of Tregs in the pathogenesis of DM, including type 1 DM, type 2 DM, latent autoimmune diabetes of adults, and gestational DM. In addition, we discuss the role of Tregs in diabetic complications, including cardiovascular diseases, nephropathy, neuropathy, and retinopathy. Tregs play a beneficial role in the pathogenesis of DM and diabetic complications, although the precise molecular mechanisms underlying the protective effect of Tregs against DM are still obscure. Collectively, modification of Tregs may provide a promising and novel future strategy for the prevention and therapy of DM and diabetic complications.

COVID-19 and Diabetes: Understanding the Interrelationship and Risks for a Severe Course

The relationship between COVID-19 and diabetes mellitus is complicated and bidirectional. On the one hand, diabetes mellitus is considered one of the most important risk factors for a severe course of COVID-19. Several factors that are often present in diabetes mellitus are likely to contribute to this risk, such as older age, a proinflammatory and hypercoagulable state, hyperglycemia and underlying comorbidities (hypertension, cardiovascular disease, chronic kidney disease and obesity). On the other hand, a severe COVID-19 infection, and its treatment with steroids, can have a specific negative impact on diabetes itself, leading to worsening of hyperglycemia through increased insulin resistance and reduced β-cell secretory function. Worsening hyperglycemia can, in turn, adversely affect the course of COVID-19. Although more knowledge gradually surfaces as the pandemic progresses, challenges in understanding the interrelationship between COVID-19 and diabetes remain.

The role of T cells in age-related diseases

Age-related T cell dysfunction can lead to failure of immune tolerance mechanisms, resulting in aberrant T cell-driven cytokine and cytotoxic responses that ultimately cause tissue damage. In this Review, we discuss the role of T cells in the onset and progression of age-associated conditions, focusing on cardiovascular disorders, metabolic dysfunction, neuroinflammation and defective tissue repair and regeneration. We present different mechanisms by which T cells contribute to inflammageing and might act as modulators of age-associated diseases, including through enhanced pro-inflammatory and cytotoxic activity, defective clearance of senescent cells or regulation of the gut microbiota. Finally, we propose that 'resetting' immune system tolerance or targeting pathogenic T cells could open up new therapeutic opportunities to boost resilience to age-related diseases.

Markers of coagulation dysfunction and inflammation in diabetic and non-diabetic COVID-19

Coagulation dysfunction and inflammatory status were compared between diabetic and non-diabetic COVID-19 patients. The standardized mean difference (SMD) and its 95% confidence interval (CI) was computed for the difference of inflammatory and hypercoagulability markers. The levels of serum ferritin (standardized mean difference-SMD: 0.47, CI 0.17–0.77, p = 0.002), C-reactive protein (SMD = 0.53, CI 0.20–0.86, p = 0.002), interleukin-6 (SMD = 0.31, CI 0.09–0.52, p = 0.005), fibrinogen (SMD = 0.31, CI 0.09–0.54, p = 0.007) and D-dimers (SMD = 0.54, CI 0.16–0.91, p = 0.005) were significantly higher in diabetic COVID-19 cases as compared to non-diabetic COVID-19 patients, suggesting more susceptibility of diabetic COVID-19 patients to coagulation dysfunction and inflammatory storm.

Early Life Exposure to Food Contaminants and Social Stress as Risk Factor for Metabolic Disorders Occurrence?-An Overview

The global prevalence of obesity has been increasing in recent years and is now the major public health challenge worldwide. While the risks of developing metabolic disorders (MD) including obesity and type 2 diabetes (T2D) have been historically thought to be essentially driven by increased caloric intake and lack of exercise, this is insufficient to account for the observed changes in disease trends. Based on human epidemiological and pre-clinical experimental studies, this overview questioned the role of non-nutritional components as contributors to the epidemic of MD with a special emphasis on food contaminants and social stress. This overview examines the impact of early life adverse events (ELAE) focusing on exposures to food contaminants or social stress on weight gain and T2D occurrence in the offspring and explores potential mechanisms leading to MD in adulthood. Indeed, summing up data on both ELAE models in parallel allowed us to identify common patterns that appear worthwhile to study in MD etiology. This overview provides some evidence of a link between ELAE-induced intestinal barrier disruption, inflammation, epigenetic modifications, and the occurrence of MD. This overview sums up evidence that MD could have developmental origins and that ELAE are risk factors for MD at adulthood independently of nutritional status.

Dapagliflozin reverses the imbalance of T helper 17 and T regulatory cells by inhibiting SGK1 in a mouse model of diabetic kidney disease

An imbalance between T helper 17 (Th17) and T regulatory (Treg) cell subsets contributes to the pathogenesis of diabetic kidney disease (DKD). However, the underlying regulatory mechanisms that cause this imbalance are unknown. Serum/glucocorticoid-regulated kinase 1 (SGK1) has been suggested to affect Th17 polarization in a salt-dependent manner, and sodium/glucose cotransporter 2 inhibitors (SGLT2i) have been demonstrated to regulate sodium-mediated transportation in the renal tubules. This study aimed to evaluate the potential benefits of dapagliflozin (Dap) on DKD, as well as its influence on shifting renal T-cell polarization and related cytokine secretion. We treated male db/db mice with Dap or voglibose (Vog) and measured blood and kidney levels of Th17 and Treg cells using flow cytometry. We found that Th17 cells were significantly increased, while Treg cells were significantly decreased in diabetic mice. Moreover, Dap suppressed the polarization of Th17/Treg cells by inhibiting SGK1 in diabetic kidneys, and this was accompanied by attenuation of albuminuria and tubulointerstitial fibrosis independent of glycemic control. Taken together, these results demonstrate that the imbalance of Th17/Treg cells plays an important role in the progression of DKD. Moreover, Dap protects against DKD by inhibiting SGK1 and reversing the T-cell imbalance.

Islet Autoimmunity in Adults With Impaired Glucose Tolerance and Recently Diagnosed, Treatment Naïve Type 2 Diabetes in the Restoring Insulin SEcretion (RISE) Study

The presence of islet autoantibodies and islet reactive T cells (T+) in adults with established type 2 diabetes (T2D) have been shown to identify those patients with more severe β-cell dysfunction. However, at what stage in the progression toward clinical T2D does islet autoimmunity emerge as an important component influencing β-cell dysfunction? In this ancillary study to the Restoring Insulin SEcretion (RISE) Study, we investigated the prevalence of and association with β-cell dysfunction of T+ and autoantibodies to the 65 kDa glutamic acid decarboxylase antigen (GADA) in obese pre-diabetes adults with impaired glucose tolerance (IGT) and recently diagnosed treatment naïve (Ndx) T2D. We further investigated the effect of 12 months of RISE interventions (metformin or liraglutide plus metformin, or with 3 months of insulin glargine followed by 9 months of metformin or placebo) on islet autoimmune reactivity. We observed GADA(+) in 1.6% of NdxT2D and 4.6% of IGT at baseline, and in 1.6% of NdxT2D and 5.3% of IGT at 12 months, but no significant associations between GADA(+) and β-cell function. T(+) was observed in 50% of NdxT2D and 60.4% of IGT at baseline, and in 68.4% of NdxT2D and 83.9% of IGT at 12 months. T(+) NdxT2D were observed to have significantly higher fasting glucose (p = 0.004), and 2 h glucose (p = 0.0032), but significantly lower steady state C-peptide (sscpep, p = 0.007) compared to T(-) NdxT2D. T(+) IGT participants demonstrated lower but not significant (p = 0.025) acute (first phase) C-peptide response to glucose (ACPRg) compared to T(-) IGT. With metformin treatment, T(+) participants were observed to have a significantly lower Hemoglobin A1c (HbA1c, p = 0.002) and fasting C-peptide (p = 0.002) compared to T(-), whereas T(+) treated with liraglutide + metformin had significantly lower sscpep (p = 0.010) compared to T(-) participants. In the placebo group, T(+) participants demonstrated significantly lower ACPRg (p = 0.001) compared to T(-) participants. In summary, T(+) were found in a large percentage of obese pre-diabetes adults with IGT and in recently diagnosed T2D. Moreover, T(+) were significantly correlated with treatment effects and β-cell dysfunction. Our results demonstrate that T(+) are an important component in T2D.

Aryl Hydrocarbon Receptor Agonist VAF347 Impedes Retinal Pathogenesis in Diabetic Mice

Diabetic retinopathy is the leading cause of blindness in the working-age population worldwide. Although the cause of diabetic retinopathy is multifactorial, IL-17A is a prevalent inflammatory cytokine involved in the promotion of diabetes-mediated retinal inflammation and the progression of diabetic retinopathy. The primary source of IL-17A is Th17 cells, which are T helper cells that have been differentiated by dendritic cells in a proinflammatory cytokine environment. Aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor that can manipulate dendritic cell maturation, halt the production of IL-6 (a proinflammatory cytokine), and suppress Th17 cell differentiation. In the current study, we examined the efficacy of an AhR agonist, VAF347, as a potential therapeutic for the onset of non-proliferative diabetic retinopathy in streptozotocin (STZ)-induced diabetic C57BL/6 mice. We determined that diabetes-mediated leukostasis, oxidative stress, and inflammation in the retina of STZ-diabetic mice were all significantly lower when treated with the AhR agonist VAF347. Furthermore, when VAF347 was subcutaneously injected into STZ-diabetic mice, retinal capillary degeneration was ameliorated, which is the hallmark of non-proliferative diabetic retinopathy in this diabetes murine model. Collectively, these findings provide evidence that the AhR agonist VAF347 could be a potentially novel therapeutic for non-proliferative diabetic retinopathy.

Gender bias in the genetic vulnerability towards type 2 diabetes and diabetic nephropathy: Role of forkhead box Protein3 transcription factor gene variants

Forkhead Box Protein3 Transcription Factor (FOXP3) gene is an essential role player in the function and differentiation of regulatory T cells. Polymorphisms/mutations in FOXP3 gene cause Treg cell dysfunction, promote autoimmunity and inflammation. Based on this presumption, we screened 600 subjects from south India (equal number of diabetic (T2DM), diabetic nephropathy (T2DN) and healthy controls) for promoter and intronic (rs3761548C/A and rs2294021C/T) polymorphisms of FOXP3 gene. PCR-RFLP method used for genotyping, revealed an association of promoter SNP for both T2DM (OR = 2.41, 95% C.I = 1.67-3.49; p < 0.0001) and T2DN (OR = 2.16, 95% C.I = 1.45-3.24; p < 0.005). While intronic polymorphism with T2DN (OR = 1.91, 95% C.I = 1.28-2.84; p < 0.05). Further, in females rs3761548C/A showed 2.6 and 5.5-fold; rs2294021C/T showed 2.2- and 2.5-fold predisposition towards T2DM and T2DN respectively. Males exhibited a twofold risk (OR = 2.01, 95% C.I = 1.22-3.30; p < 0.05) towards T2DM with promoter and no association with intronic polymorphism. The combined genotypes in females with AA-CC; AA-TT predisposed and CA-CC; CA-CT protected heading towards T2DM and T2DN respectively, suggesting irrespective of type of allele at intronic locus AA and CA at promoter locus promote or protect the individual for diabetes and diabetic nephropathy, further confirmed by MLR. To our knowledge, the current study is the first of its kind that revealed an association of these polymorphisms of FOXP3 gene and gender influence on T2DM and T2DN among South Indians. Functional and cell-based studies on Treg cells are warranted to confirm our results that help to develop FOXP3/Treg based therapeutic interventions. Lack of data on Treg cells is the limitation of this study.

Changes in T helper cell-related factors in patients with type 2 diabetes mellitus after empagliflozin therapy

The immune factors related to T helper (Th) 1 (T-bet, STAT1, and IFN-γ), Th17 (ROR-γt, STAT3, and IL-17), and Treg (FOXP3, STAT5, and IL-10) cells, and SOCS1/3 and the proliferation of Th cells were investigated in type 2 diabetes mellitus patients before (baseline) and after empagliflozin therapy. A total of 56 patients on metformin and gliclazide were separated into two groups: Group 1 did not receive empagliflozin (EMPA^-) and the Group 2 received 10 mg/day of empagliflozin for 6 months (EMPA⁺). The expressions of T-bet, ROR-γt, FOXP3, STAT1/3/5 and SOCS1/3 were evaluated in CD4⁺ T cells with real-time PCR. The production of IFN-γ, IL-17, and IL-10 from CD4⁺ T cells was measured using ELISA. The proliferation of Th cells was assessed with flow cytometry. Six months of empagliflozin therapy significantly reduced the expression of ROR-γt and increased FOXP3 and STAT5 expression, compared to baseline. Production of IL-17 decreased after empagliflozin treatment, while IL-10 was enhanced in the EMPA⁺ group. Oral administration of empagliflozin or the addition of empagliflozin to the cell cultures diminished the proliferation of Th cells. Empagliflozin showed anti-inflammatory effects on Th cells by decreasing Th17-related factors, reducing proliferation capacity, and increasing Treg cell properties.

Anti- and non-tumor necrosis factor-α-targeted therapies effects on insulin resistance in rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis

In addition to β-cell failure with inadequate insulin secretion, the crucial mechanism leading to establishment of diabetes mellitus (DM) is the resistance of target cells to insulin, i.e. insulin resistance (IR), indicating a requirement of beyond-normal insulin concentrations to maintain euglycemic status and an ineffective strength of transduction signaling from the receptor, downstream to the substrates of insulin action. IR is a common feature of most metabolic disorders, particularly type II DM as well as some cases of type I DM. A variety of human inflammatory disorders with increased levels of proinflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1β, have been reported to be associated with an increased risk of IR. Autoimmune-mediated arthritis conditions, including rheumatoid arthritis (RA), psoriatic arthritis (PsA) and ankylosing spondylitis (AS), with the involvement of proinflammatory cytokines as their central pathogenesis, have been demonstrated to be associated with IR, especially during the active disease state. There is an increasing trend towards using biologic agents and small molecule-targeted drugs to treat such disorders. In this review, we focus on the effects of anti-TNF-α- and non-TNF-α-targeted therapies on IR in patients with RA, PsA and AS. Anti-TNF-α therapy, IL-1 blockade, IL-6 antagonist, Janus kinase inhibitor and phospho-diesterase type 4 blocker can reduce IR and improve diabetic hyper-glycemia in autoimmune-mediated arthritis.

Temporal metabolic and transcriptomic characteristics crossing islets and liver reveal dynamic pathophysiology in diet-induced diabetes

To investigate the molecular mechanisms underlying islet dysfunction and insulin resistance in diet-induced diabetes, we conducted temporal RNA sequencing of tissues responsible for insulin secretion (islets) and action (liver) every 4 weeks in mice on high-fat (HFD) or chow diet for 24 weeks, linking to longitudinal profile of metabolic characteristics. The diverse responses of α, β, and δ cells to glucose and palmitate indicated HFD-induced dynamic deterioration of islet function from dysregulation to failure. Insulin resistance developed with variable time course in different tissues. Weighted gene co-expression network analysis and Ingenuity Pathway Analysis implicated islets and liver jointly programmed β-cell compensatory adaption via cell proliferation at early phase and irreversible islet dysfunction by inappropriate immune response at later stage, and identified interconnected molecules including growth differentiation factor 15. Frequencies of T cell subpopulation showed an early decrement in Tregs followed by increases in Th1 and Th17 cells during progression to diabetes.

The glucagon-like peptide-1 (GLP-1) analog exenatide ameliorates intrauterine adhesions in mice

OBJECTIVE

The purpose of the experiments in this study was to explore the effect of exenatide on intrauterine adhesions (IUAs) and to elucidate its mechanism to provide new ideas for the clinical treatment of IUAs.

METHODS

In this study, an animal model of IUAs was established by double stimulation using mechanical curettage and inflammation. After modeling, the treatment group was injected subcutaneously with three doses of exenatide for two weeks. The model group was injected with sterile ultrapure water, and the sham operation group was treated the same as the normal group, except for the observation of abdominal wound changes. Two weeks later, all mice were sacrificed by cervical dysfunction. The obtained mouse uterine tissue was used for subsequent experimental detection, using HE and Masson staining for histomorphological and pathological analysis; qRT-PCR for the detection of TGF-β1, α-SMA, and MMP-9 gene expression in uterine tissue; and western blotting analysis of TGF-β1, α-SMA, and collagen 1 protein expression to verify whether exenatide has a therapeutic effect on IUAs in mice.

RESULTS

In the high-dose exenatide treatment group, the endometrial glands significantly increased in size, and the deposition area of collagen fibers in the endometrial tissue was significantly reduced. We observed that the mRNA expression of TGF-β1 and α-SMA in the endometrial tissue of IUAs mice in this group was significantly reduced, while the expression of MMP-9 was significantly increased. In addition, we found that the protein expression of TGF-β1, α-SMA, and collagen 1 remarkably decreased after treatment with exenatide.

CONCLUSION

Exenatide may reduce the deposition of collagen fibers in the uterus of IUAs mice and promote the proliferation of endometrial glands in mice.

Virus Infections and Host Metabolism-Can We Manage the Interactions?

When viruses infect cells, they almost invariably cause metabolic changes in the infected cell as well as in several host cell types that react to the infection. Such metabolic changes provide potential targets for therapeutic approaches that could reduce the impact of infection. Several examples are discussed in this review, which include effects on energy metabolism, glutaminolysis and fatty acid metabolism. The response of the immune system also involves metabolic changes and manipulating these may change the outcome of infection. This could include changing the status of herpesviruses infections from productive to latency. The consequences of viral infections which include coronavirus disease 2019 (COVID-19), may also differ in patients with metabolic problems, such as diabetes mellitus (DM), obesity, and endocrine diseases. Nutrition status may also affect the pattern of events following viral infection and examples that impact on the pattern of human and experimental animal viral diseases and the mechanisms involved are discussed. Finally, we discuss the so far few published reports that have manipulated metabolic events in-vivo to change the outcome of virus infection. The topic is expected to expand in relevance as an approach used alone or in combination with other therapies to shape the nature of virus induced diseases.

Gender dependent differences in lipid metabolism in individuals with type 2 diabetes mellitus

Aim

The present study investigates gender dependent effects of insulin resistance on lipid profile and adipocytokines in individuals with diabetes receiving oral antidiabetic drugs (OADs). The aim was also to reveal the changes in the expression of genes involved in lipid metabolism and inflammation.

Methods

Lipid profile, adipocytokine levels and homeostatic model assessment of insulin resistance (HOMA-IR) was assessed in 100 patients with diabetes (M = 43, F = 57) matched for age and gender with healthy individuals (M = 45, F = 55). The expression pattern of genes was analyzed by quantitative real time PCR.

Results

Males consuming metformin with other drugs exhibited a positive association between HOMA-IR and cholesterol, triglyceride and very low density lipoprotein (VLDL). Females consuming only metformin and metformin with other drugs, showed a positive association of HOMA-IR with cholesterol and a negative association with adiponectin. In males and females with diabetes, a comparable expression of peroxisome proliferator activated receptor γ (PPARγ) while higher expression of sterol regulatory element binding protein 1 (SREBP1) was observed. Expression of fatty acid synthase (FAS), long chain acyl CoA Synthetases (ACSL), malonyl-CoA-acyl carrier protein transacylase (MCAT) and nuclear factor kappa β (NFkβ) was higher in men with diabetes than healthy males. Expression of tumor necrosis factor α (TNF-α) was higher in males and females with diabetes than respective healthy genders.

Conclusion

Insulin resistance adversely affects lipid profile, adipocytokines in males with type 2 diabetes. Expression of genes involved in lipid metabolism and inflammation is found to be undesirably and differentially altered in both the genders.

Obesity and diabetes as high-risk factors for severe coronavirus disease 2019 (Covid-19)

The outbreak of the coronavirus disease 2019 (Covid-19) has become an evolving worldwide health crisis. With the rising prevalence of obesity and diabetes has come an increasing awareness of their impacts on infectious diseases, including increased risk for various infections, post-infection complications and mortality from critical infections. Although epidemiological and clinical characteristics of Covid-19 have been constantly reported, no article has systematically illustrated the role of obesity and diabetes in Covid-19, or how Covid-19 affects obesity and diabetes, or special treatment in these at-risk populations. Here, we present a synthesis of the recent advances in our understanding of the relationships between obesity, diabetes and Covid-19 along with the underlying mechanisms, and provide special treatment guidance for these at-risk populations.

Obesity and chronic inflammation crosslinking

The adipose tissue has been recognized as an active organ involved in numerous metabolic, hormonal and immunological processes. Obesity and associated chronic inflammation leads to many metabolic and autoimmune disorders. The number of cells, their phenotype and distribution in adipose tissue depends on the degree of obesity. Polarization of macrophages towards M1, neutrophils influx to adipose tissue, activation of Th1 and Th17 cells and increased level of proinflammatory cytokines are characteristic for obesity-induced inflammation. Several mechanisms, such as adipocytes’ hypoxia, oxidative stress, endoplasmic reticulum stress, impairment of PPAR receptors, inflammasomes’ activation and activation of TLR are involved into development of chronic obesity-induced inflammation. A better understanding of this processes can provide new treatments for obesity and related disorders.

Dietary exposure to chlorpyrifos affects systemic and hepatic immune-cell phenotypes in diabetic mice

Hyperglycemia induces low-grade systemic inflammation and immune dysregulation, leading to overstated reactions to immune stimuli and diabetes-related organ damage. Tissue inflammation is characterized by leukocyte infiltration, and T cells play crucial roles in directing leukocyte-mediated inflammatory responses. The aim of the study was to investigate the effects of dietary exposure to chlorpyrifos (CPF) on systemic and hepatic immune-cell phenotypes in C57BL/6 mice with streptozotocin (STZ)-induced diabetes. Mice received an intraperitoneal injection of STZ for 5 consecutive days to induce diabetes, and diabetic mice were given either an AIN-93-based control diet or a CPF-containing diet at doses of 0.5, 1, or 2 mg/kg body weight/day for 28 days. Results showed that dietary exposure to CPF had no influence on the body weight or the erythrocyte hemoglobin A1c level in diabetic mice. Both blood and hepatic neutrophil populations were enhanced by CPF exposure. CPF-exposed groups had lower percentages of blood T cells without altering the proportions of CD4⁺ and CD8⁺ T-cell subsets, and lower expression levels of the Bcl-2 antiapoptotic gene in the spleen. CPF exposure reduced the percentage of blood regulatory T cells (Tregs); however, the Treg population was upregulated in the liver even when hepatic T cells were not affected by CPF in diabetic mice. Hepatic expressions of Treg-related genes were suppressed in all CPF-exposed groups. Higher plasma levels of aspartate aminotransferase and expression levels of the hepatic interleukin-1β gene were observed in diabetic mice exposed to medium and high doses of CPF. These findings suggest that dietary exposure to CPF affects the distribution of both myeloid and lymphoid immune cells in the blood and liver under hyperglycemic conditions, which may lead to hyperinflammation when encountering immune stimuli.

Proinflammatory cytokine polarization in type 2 diabetes

Subclinical inflammatory reaction is associated with non-insulin dependent diabetes. Therefore, the aim of the present study is to describe the effect of the three cytokines: interferon γ (IFN-γ), interleukin (IL)-4 and IL-5 on the development of type 2 diabetes (T2D). Forty-five volunteers (after their permission) were participated in this work; according to their clinical examination and laboratory investigations (fasting blood sugar, 2 hours postprandial, HbA1c and lipid profile), they were divided into thirteen control (non-diabetic) (five females and eight males) and thirty-two diabetic patients (twenty-one females and eleven males). Thereafter, their sera were evaluated for C-reactive protein (CRP), IFN-γ, IL-4 and IL-5. The results revealed an increasing trend of CRP and a significant increase of IFN-γ in diabetic patients with no sex difference. A positive correlation between IFN-γ and both IL-4 and IL-5 in control, and a positive correlation between IL-4 and IL-5 in diabetic patients had been visualized. These results denoted that there may be an association of the pro-inflammatory cytokines in the etiology of diabetes mellitus type 2.

Novel standardized method for extracellular flux analysis of oxidative and glycolytic metabolism in peripheral blood mononuclear cells

Analyzing metabolism of peripheral blood mononuclear cells (PBMCs) provides key opportunities to study the pathophysiology of several diseases, such as type 2 diabetes, obesity and cancer. Extracellular flux (XF) assays provide dynamic metabolic analysis of living cells that can capture ex vivo cellular metabolic responses to biological stressors. To obtain reliable data from PBMCs from individuals, novel methods are needed that allow for standardization and take into account the non-adherent and highly dynamic nature of PBMCs. We developed a novel method for extracellular flux analysis of PBMCs, where we combined brightfield imaging with metabolic flux analysis and data integration in R. Multiple buffy coat donors were used to demonstrate assay linearity with low levels of variation. Our method allowed for accurate and precise estimation of XF assay parameters by reducing the standard score and standard score interquartile range of PBMC basal oxygen consumption rate and glycolytic rate. We applied our method to freshly isolated PBMCs from sixteen healthy subjects and demonstrated that our method reduced the coefficient of variation in group mean basal oxygen consumption rate and basal glycolytic rate, thereby decreasing the variation between PBMC donors. Our novel brightfield image procedure is a robust, sensitive and practical normalization method to reliably measure, compare and extrapolate XF assay data using PBMCs, thereby increasing the relevance for PBMCs as marker tissue in future clinical and biological studies, and enabling the use of primary blood cells instead of immortalized cell lines for immunometabolic experiments.

Increased metformin dosage suppresses pro-inflammatory cytokine levels in systemic circulation and might contribute to its beneficial effects

Type 2 Diabetes Mellitus (T2DM) is a metabolic disorder, characterized by persistent elevation of blood glucose either due to insulin resistance or insulin insufficiency. Metformin is the recommended first choice of drug for the management of T2DM and is known to improve insulin sensitivity and prevents hyperglycemia by reducing chronic inflammation. T-helper type 1 (Th1) and type 17 (Th17) cells, are important pro-inflammatory CD4⁺ T cell subsets secreting TNF-α, and INF-γ (Th1), and interleukin 17 (Th17). These cytokines have been shown to play a crucial role in inflammation, insulin resistance, and the development of T2DM. Here, we explore the effect of different metformin dosages on pro-inflammatory cytokine (TNF-α, INF-γ, GM-CSF and IL-17) levels in systemic circulation among T2DM patients in Ghana, since inflammatory responses and cytokines play significant roles in the pathogenesis and progression of T2DM patients on metformin. Two hundred and nine (209) consenting T2DM patients receiving treatment at the Diabetic unit of the Komfo Anokye Teaching Hospital (KATH) in the Ashanti region of Ghana were recruited in a hospital-based cross-sectional study design. Blood samples were collected and serum obtained from each participant were analyzed for the concentrations of TNF-α, INF-γ, GM-CSF and IL-17 cytokine levels by solid-phase sandwich ELISA. We observed that participants on 3000 mg/day dose of metformin had significantly lower levels of TNF-α (p < .001) and IFN-γ (p = .014) compared to those on other dosages (1000 mg and 2000 mg/day). However, GM-CSF and IL-17 levels were not affected by increased metformin dosages. After adjusting for age, gender, dose and duration of metformin use, we observed that participants who took higher doses of metformin had significantly reduced levels of TNF-α (β = -0.0297, 95% CI = (-0.005 to -0.002) p < .001. Metformin dosage independently predicted reduced TNF-α levels with 14.4% variations in the metformin dosage levels. Increased metformin dosage suppresses TNF-α levels in systemic circulation and hence might contribute to its beneficial effects.

The Potential Causes of Cystic Fibrosis-Related Diabetes

Cystic fibrosis (CF) is a genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR). Cystic fibrosis-related diabetes (CFRD) is the most common comorbidity, affecting more than 50% of adult CF patients. Despite this high prevalence, the etiology of CFRD remains incompletely understood. Studies in young CF children show pancreatic islet disorganization, abnormal glucose tolerance, and delayed first-phase insulin secretion suggesting that islet dysfunction is an early feature of CF. Since insulin-producing pancreatic β-cells express very low levels of CFTR, CFRD likely results from β-cell extrinsic factors. In the vicinity of β-cells, CFTR is expressed in both the exocrine pancreas and the immune system. In the exocrine pancreas, CFTR mutations lead to the obstruction of the pancreatic ductal canal, inflammation, and immune cell infiltration, ultimately causing the destruction of the exocrine pancreas and remodeling of islets. Both inflammation and ductal cells have a direct effect on insulin secretion and could participate in CFRD development. CFTR mutations are also associated with inflammatory responses and excessive cytokine production by various immune cells, which infiltrate the pancreas and exert a negative impact on insulin secretion, causing dysregulation of glucose homeostasis in CF adults. In addition, the function of macrophages in shaping pancreatic islet development may be impaired by CFTR mutations, further contributing to the pancreatic islet structural defects as well as impaired first-phase insulin secretion observed in very young children. This review discusses the different factors that may contribute to CFRD.

Diabetes Mellitus and SARS-CoV-2 Infection: Pathophysiologic Mechanisms and Implications in Management

INTRODUCTION

Currently, diabetes mellitus (DM), as well as coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are major public health issues worldwide.

BACKGROUND

It has been suggested that patients with DM are more vulnerable to SARS-CoV-2 infection and suffer from more severe forms of the disease.

METHODS

A literature search was performed using PubMed, Scopus, and Google search engines.

RESULTS

Angiotensin-converting enzyme-2 (ACE2) is the major receptor of SARS-CoV-2 in the human host. The differential expression of ACE2 in the lungs of patients with DM makes them more susceptible to COVID-19. Additionally, acute or chronic hyperglycemia renders individuals in an immune-suppressive state, with impaired innate and adaptive immunity function, also contributing to the severity of COVID-19 infection among patients with DM. Other factors contributing to a more severe course of COVID-19 include the coexistence of obesity in T2DM, the endothelial inflammation induced by the SARS-CoV-2 infection, which aggravates the endothelial dysfunction observed in both T1DM and T2DM, and the hypercoagulability presented in COVID-19 infection that increases the thrombotic tendency in DM.

CONCLUSION

This review summarizes the pathophysiologic mechanisms underlying the coexistence of both pandemics as well as the current recommendations and future perspectives regarding the optimal treatment of inpatients and outpatients with DM in the era of SARS-CoV-2 infection. Notably, the currently recommended drugs for the treatment of severe COVID-19, dexamethasone and remdesivir, may cause hyperglycemia, an adverse effect that physicians should bear in mind when caring for patients with DM and COVID-19.

Synergistic Effect of Omega-3 Fatty Acids and Oral-Hypoglycemic Drug on Lipid Normalization through Modulation of Hepatic Gene Expression in High Fat Diet with Low Streptozotocin-Induced Diabetic Rats

Type 2 diabetes mellitus, which an outcome of impaired insulin action and its secretion, is concomitantly associated with lipid abnormalities. The study was designed to evaluate the combinational effect of omega-3 fatty acids (flax and fish oil) and glibenclamide on abnormal lipid profiles, increased blood glucose, and impaired liver and kidney functions in a high fat diet with low streptozotocin (STZ)-induced diabetic rats, including its probable mechanism of action. The male Wistar rats (n = 48) were distributed into eight groups. All animal groups except the healthy received a high fat diet (HFD) for 90 days. Further, diabetes was developed by low dose STZ (35 mg/kg). Diabetic animals received, omega-3 fatty acids (500 mg/kg), along with glibenclamide (0.25 mg/kg). Both flax and fish oil intervention decreased (p ≤ 0.001) serum triglycerides and very low density lipoprotein and elevated (p ≤ 0.001) high density lipoprotein levels in diabetic rats. Total cholesterol and low-density lipoprotein level was decreased (p ≤ 0.001) in fish oil-treated rats. However, it remained unaffected in the flax oil treatment group. Both flax and fish oil intervention downregulate the expression of fatty acid metabolism genes, transcription factors (sterol regulatory element-binding proteins-1c and nuclear factor-κβ), and their regulatory genes i.e., acetyl-coA carboxylase alpha, fatty acid synthase, and tumor necrosis factors-α. The peroxisome proliferator-activated receptor gamma gene expression was upregulated (p ≤ 0.001) in the fish oil treatment group. Whereas, carnitine palmitoyltransferase 1 and fatty acid binding protein gene expression were upregulated (p ≤ 0.001) in both flax and fish oil intervention group.

Evaluation of Interleukin-23 and JAKs/STATs/SOCSs/ROR-γt Expression in Type 2 Diabetes Mellitus Patients Treated With or Without Sitagliptin

The production of interleukin-23 (IL-23) and the expression levels of related genes were evaluated in type 2 diabetes mellitus patients. The correlations between them were also determined. Thirty patients without sitagliptin (sitagliptin negative; SN), 30 patients with sitagliptin (sitagliptin positive; SP), and 30 healthy controls (HCs) were recruited. The level of IL-23 in the supernatant of anti CD3-activated peripheral blood mononuclear cells (PBMCs) was assessed using enzyme-linked immunosorbent assay. The expressions of IL-23, JAK1/JAK2/TYK2, STAT1/STAT3, ROR-γt, and SOCS1/SOCS3 in PBMCs were evaluated by real-time polymerase chain reaction. The production of IL-23 and the expressions of IL-23, JAK2, STAT3, and ROR-γt were observed to be enhanced in SN patients versus HCs, while the levels were decreased in SP patients versus SN patients (P < 0.05). SOCS1 and SOCS3 expressions were lower in SN patients than HCs, and their expressions were elevated in SP patients versus SN patients (P < 0.05). In SN patients, positive correlations between the IL-23 with fasting plasma glucose and HbA1c were observed, and JAK2/STAT3/ROR-γt were positively correlated with IL-23. JAK2, STAT3, and ROR-γt were positively related to each other and were negatively related to SOCS3. Enhanced IL-23/JAK2/STAT3/ROR-γt and reduced SOCS1/SOCS3 were found in SN patients. Sitagliptin may regulate the IL-23 and related gene expression.

Individuals with obesity and COVID-19: A global perspective on the epidemiology and biological relationships

The linkage of individuals with obesity and COVID-19 is controversial and lacks systematic reviews. After a systematic search of the Chinese and English language literature on COVID-19, 75 studies were used to conduct a series of meta-analyses on the relationship of individuals with obesity-COVID-19 over the full spectrum from risk to mortality. A systematic review of the mechanistic pathways for COVID-19 and individuals with obesity is presented. Pooled analysis show individuals with obesity were more at risk for COVID-19 positive, >46.0% higher (OR = 1.46; 95% CI, 1.30-1.65; p < 0.0001); for hospitalization, 113% higher (OR = 2.13; 95% CI, 1.74-2.60; p < 0.0001); for ICU admission, 74% higher (OR = 1.74; 95% CI, 1.46-2.08); and for mortality, 48% increase in deaths (OR = 1.48; 95% CI, 1.22-1.80; p < 0.001). Mechanistic pathways for individuals with obesity are presented in depth for factors linked with COVID-19 risk, severity and their potential for diminished therapeutic and prophylactic treatments among these individuals. Individuals with obesity are linked with large significant increases in morbidity and mortality from COVID-19. There are many mechanisms that jointly explain this impact. A major concern is that vaccines will be less effective for the individuals with obesity.

Distinguishable Immunologic Characteristics of COVID-19 Patients with Comorbid Type 2 Diabetes Compared with Nondiabetic Individuals

Background

COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has threatened every civilian as a global pandemic. The immune system poses the critical interactive chain between the human body and the virus. Here, we make efforts to examine whether comorbidity with type 2 diabetes (T2D) affects the immunological response in COVID-19 patients.

Methods

We conducted a retrospective pilot study investigating immunological characteristics of confirmed cases of COVID-19 with or without comorbid T2D. Two subcohorts of sex- and age-matched participants were eligible for data analysis, of which 33 participants were with T2D and the remaining 37 were nondiabetic (NDM). Cellular immunity was assessed by flow cytometric determination of surface markers including CD3, CD4, CD8, CD19, CD16, and CD56 in peripheral blood. Levels of C reactive protein, immunoglobulin (IgG, IgM, IgA, and IgE), and complements (C3, C4) were detected by rate nephelometry immunoassay. And Th1/Th2 cytokines (IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ) were detected by Cytometric Bead Array.

Results

Neutrophil counts were found to be significantly higher in the T2D group than in the NDM group and had a significant relevance with clinical severity. Lymphocyte frequencies showed no significant differences in the two groups. However, the proportions and absolute counts of T, Tc, Th, and NK cells decreased in both groups to different degrees. An abnormal increase in neutrophil count and a decrease in lymphocyte subpopulations may represent risk factors of COVID-19 severity. The level of IgG, IgM, IgA, C3, and C4 showed no significant difference between the two groups, while the IgE levels were higher in the T2D group than in the NDM group (p < 0.05). Th1 cytokines including IFN-γ, TNF-α, and IL-6, as well as CRP, appeared significantly higher in the T2D group.

Conclusions

The COVID-19 patients comorbid with T2D demonstrated distinguishable immunological parameters, which represented clinical relevancies with the predisposed disease severity in T2D.

Gene expression of the immunoinflammatory and immunological status of obese dogs before and after weight loss

Obesity is characterized by a low degree of chronic inflammation state that, along with metabolic modifications, promotes important changes in the animal's organism. Adipose tissue actively participates in inflammation and immunity, and several defense cells of the organism may, therefore, be involved in the diversity found between obese and ideal weight individuals. Studies regarding this subject have shown immune cell changes in humans and rats, however, the literature is scarce in relation to dogs. Thus, the present study aimed to evaluate the gene expression profile of immunoinflammatory response and the lymphoproliferation of obese dogs before and after weight loss. Eight female dogs, neutered, of different breeds, aged between 1 and 8 years (4.74±3.19), obese, with body condition score (BCS) of 9 out of a 9-point scale and body composition determined by the deuterium isotope dilution method were included. The obese dogs were enrolled in a weight loss program and after losing 20% of their initial weight became a second experimental group. A third experimental group consisted of eight female dogs, neutered, aged between 1 and 8 years (3.11±0.78) and with ideal BCS (5 out of a 9-point scale). Gene expression of immunoinflammatory cytokines (resistin, leptin, adiponectin, TNF-α, IL-6, IL-8, and IL-10) was assessed by qRT-PCR and immunity was assessed by lymphoproliferative response using the flow cytometry technique. The data that presented normal distribution was evaluated by analysis of variance by the PROC MIXED of the SAS and when differences were detected, these were compared by the Tukey test. Regarding the gene expression data, the procedure PROC GLIMMIX was adopted and the methodology of generalized linear model was used, in which the Gama distribution proved to be adequate. Values of p<0.05 were considered significant. The mean weight loss period of the animals included in the study was 194.25 ± 28.31 days and the mean weekly weight loss rate was 1.02 ± 0.82%. The average fat mass, both in percentage (P<0.001) and in kilograms (P = 0.012), was higher in the obese group (40.88%; 8.91kg), returning to normal and without difference between the control group (19.16%; 3.01kg) and after weight loss (22.10%; 4.11kg). The weight loss program resulted in an increase in percentage of lean body mass (P = 0.001), 55.50% in obese animals vs 77.90% in obese dogs after weight loss, the latter with no difference when compared to the control group (80.84%). The obese group presented increased gene expression of resistin and IL-8 in relation to the weight loss group (P = 0.002). In adiponectin, the obese group presented increased mRNA gene expression when compared to the weight loss group (P = 0.003). The evaluation of lymphocyte proliferation showed differences between the group of obese animals before and after weight loss (P = 0.004). Weight loss resulted in an increase in the lymphoproliferation rate (18.48%) compared to obese dogs at the beginning of the study (10.71%). These results indicate that weight loss modulates the immunoinflammatory response of obese dogs and may present important benefits to health and longevity of dogs.

Diabetes, infection risk and COVID-19

BACKGROUND

Individuals with diabetes are at a greater risk of hospitalization and mortality resulting from viral, bacterial, and fungal infections. The coronavirus disease-2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has spread quickly to more than 213 countries and claimed 395,779 lives as of June 7, 2020. Notably, in several studies, diabetes is one of the most reported comorbidities in patients with severe COVID-19.

SCOPE OF REVIEW

In this review, I summarize the clinical data on the risk for infectious diseases in individuals with diabetes while highlighting the mechanisms for altered immune regulation. The focus is on coronaviruses. Based on the new clinical data obtained from COVID-19 patients, a discussion of mechanisms, such as cytokine storm, pulmonary and endothelial dysfunction, and hypercoagulation, that may render individuals with diabetes more vulnerable to COVID-19 is provided.

MAJOR CONCLUSIONS

Epidemiological studies show that poorly controlled diabetes is a risk factor for various infectious diseases. Given the global burden of diabetes and the pandemic nature of coronaviruses, understanding how diabetes affects COVID-19 severity is critical to designing tailored treatments and clinical management of individuals affected by diabetes.

Increased AHR Transcripts Correlate With Pro-inflammatory T-Helper Lymphocytes Polarization in Both Metabolically Healthy Obesity and Type 2 Diabetic Patients

Aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor whose transcription activity is regulated by small compounds provided by diet, xenobiotics, and metabolism. It has been proven to be involved in energy homeostasis and inflammation in most recent years. Epidemiologically, exposure to xenobiotic AHR ligands contributes to obesity and type 2 diabetes (T2D). AHR is also the critical transcription factor determining the lineage commitment of pro-inflammatory Th17 and Th22 cells from naïve CD4+ T lymphocytes. It has been well-illustrated in animal models that IL-22, the major effector cytokine of Th17 and Th22 cells, played a major role in the interaction of metabolism and gut microbiota. But there were still missing links between gut microbiota, IL-22, and metabolism in humans. Our previous findings indicated that elevated circulating levels of IL-22 and frequencies of Th22 cells were associated with insulin resistance in both patients with obesity and T2D. Additionally, the hyperactive Th17 and Th22 cells phenotype also correlate with islets β-cell dysfunction in T2D. In this study, we made efforts to determine AHR expressions in peripheral blood mononuclear cells (PBMCs) from patients with T2D and metabolically healthy obesity (MHO). Correlation analyses were conducted to assess the possible link between AHR and the metabolic and inflammatory context. We revealed that mRNA expression of AHR was up-regulated and correlated with the percentage of Th17, Th22 as well as Th1 cells. Elevated plasma levels of IL-22 and IL-17 also correlated with increased AHR transcripts in PBMCs from both MHO and T2D patients. The transcription factor AHR may thus have a plausible role in the interaction between metabolism and pro-inflammatory status of patients in the development of obesity and T2D.

Effects of Adenovirus-Mediated Overexpression of JAZF1 on Chronic Inflammation: An In Vitro and In Vivo Study

BACKGROUND Insulin sensitivity and inflammation can be affected by juxtaposition with another zinc finger gene 1 (JAZF1), but its precise role in chronic inflammation is unclear. In this study, JAZF1-overexpression adenovirus plasmids were transfected into macrophages, CD4⁺ T cells, and C57BL/6J mice to assess the role of JAZF1 in chronic inflammation. MATERIAL AND METHODS JAZF1 was cloned into an adenovirus skeleton plasmid and transfected in HEK293 cells to package and enrich the virus particles. In vitro, the JAZF1 overexpression adenovirus vector (PAD-JAZF1) was cultured with peritoneal macrophages and peripheral blood CD4⁺ T cells of C57BL/6J mice, and samples were evaluated using flow cytometry. In vivo, PAD-JAZF1 was introduced into C57BL/6J mice, and livers were collected to evaluate factors related to inflammation by hematoxylin & eosin and immunohistochemical staining. RESULTS In vitro, PAD-JAZF1 decreased total macrophages, CD11c⁺ macrophages, and the secretion of proinflammatory cytokines, but increased CD206⁺ macrophages. It also decreased total CD4⁺T cells, active T cells, memory T cells, and the secretion of IL-6, IL-10, and IFN-γ, but increased Treg cells and restrictive T cells. In vivo, compared to those in the control group transfected with the adenovirus skeleton vector, mice transfected with the PAD-JAZF1 recombinant adenovirus had fewer CD11c⁺ ATMs and CD4⁺ T cells, lower levels of TNF-alpha and IL-6, and higher IL-10 concentrations in the liver. CONCLUSIONS These findings indicate that JAZF1 limits chronic inflammation by reducing macrophage and CD4⁺T cell populations, altering subtype differentiation, and regulating the secretion of immune-related factors.