Reduced post-operative DPP4 activity associated with worse patient outcome after cardiac surgery

Decreased circulating dipeptidyl peptidase-4 enzyme activity is prognostic for severe outcomes in COVID-19 inpatients

Aim:

To investigate the serum circulating DPP4 activity in patients with COVID-19 disease.

Materials & methods:

Serum samples from 102 hospitalized COVID-19 patients and 43 post-COVID-19 plasma donors and 39 SARS-CoV-2 naive controls and their medical data were used. Circulating DPP4 activities according to different COVID-19 disease peak severity (WHO) groups at sampling and at peak were assessed.

Results:

A significant decrease (p < 0.0001) in serum DPP4 activity was found in study groups of higher disease severity. When the circulating DPP4 activity was assessed as a prognostic marker, the logistic regression (p = 0.0023) indicated that the enzyme activity is a predictor of mortality (median 9.5 days before death) with receiver operating characteristic area under the curves of 73.33% (p_{[area = 0.5]} < 0.0001) as single predictor and 83.45% (p_{[area = 0.5]} < 0.0001) in combination with age among hospitalized patients with COVID-19.

Conclusion:

Decreased circulating DPP4 activity is associated with severe COVID-19 disease and is a strong prognostic biomarker of mortality.

Optical genome mapping identifies rare structural variations as predisposition factors associated with severe COVID-19

Impressive global efforts have identified both rare and common gene variants associated with severe COVID-19 using sequencing technologies. However, these studies lack the sensitivity to accurately detect several classes of variants, especially large structural variants (SVs), which account for a substantial proportion of genetic diversity including clinically relevant variation. We performed optical genome mapping on 52 severely ill COVID-19 patients to identify rare/unique SVs as decisive predisposition factors associated with COVID-19. We identified 7 SVs involving genes implicated in two key host-viral interaction pathways: innate immunity and inflammatory response, and viral replication and spread in nine patients, of which SVs in STK26 and DPP4 genes are the most intriguing candidates. This study is the first to systematically assess the potential role of SVs in the pathogenesis of COVID-19 severity and highlights the need to evaluate SVs along with sequencing variants to comprehensively associate genomic information with interindividual variability in COVID-19 phenotypes.

Identification of DPP4/CTNNB1/MET as a Theranostic Signature of Thyroid Cancer and Evaluation of the Therapeutic Potential of Sitagliptin

Simple Summary

In recent years, the incidence of thyroid cancer has been increasing globally, with papillary thyroid cancer (PTCa) being the most prevalent pathological type. Although PTCa has been regarded to be slow growing and has a good prognosis, in some cases, PTCa can be aggressive and progress despite surgery and radioactive iodine treatment. Therefore, searching for new targets and therapies is required. We utilized bioinformatics analyses to identify critical theranostic markers for PTCa. We found that DPP4/CTNNB1/MET is an oncogenic signature that is overexpressed in PTCa and associated with disease progression, distant metastasis, treatment resistance, immuno-evasive phenotypes, and poor clinical outcomes. Interestingly, our in silico molecular docking results revealed that sitagliptin, an antidiabetic drug, has strong affinities and potential for targeting DPP4/CTNNB1/MET signatures, even higher than standard inhibitors of these genes. Collectively, our findings suggest that sitagliptin could be repurposed for treating PTCa.

Abstract

In recent years, the incidence of thyroid cancer has been increasing globally, with papillary thyroid cancer (PTCa) being the most prevalent pathological type, accounting for approximately 80% of all cases. Although PTCa has been regarded to be slow growing and has a good prognosis, in some cases, PTCa can be aggressive and progress despite surgery and radioactive iodine treatment. In addition, most cancer treatment drugs have been shown to be cytotoxic and nonspecific to cancer cells, as they also affect normal cells and consequently cause harm to the body. Therefore, searching for new targets and therapies is required. Herein, we explored a bioinformatics analysis to identify important theranostic markers for THCA. Interestingly, we identified that the DPP4/CTNNB1/MET gene signature was overexpressed in PTCa, which, according to our analysis, is associated with immuno-invasive phenotypes, cancer progression, metastasis, resistance, and unfavorable clinical outcomes of thyroid cancer cohorts. Since most cancer drugs were shown to exhibit cytotoxicity and to be nonspecific, herein, we evaluated the anticancer effects of the antidiabetic drug sitagliptin, which was recently shown to possess anticancer activities, and is well tolerated and effective. Interestingly, our in silico molecular docking results exhibited putative binding affinities of sitagliptin with DPP4/CTNNB1/MET signatures, even higher than standard inhibitors of these genes. This suggests that sitagliptin is a potential THCA therapeutic, worthy of further investigation both in vitro and in vivo and in clinical settings.

Mesenchymal stem cells-originated exosomal microRNA-152 impairs proliferation, invasion and migration of thyroid carcinoma cells by interacting with DPP4

BACKGROUND

Thyroid carcinoma (THCA) is the most prevalent tumor in the endocrine system with an increasing incidence. Recent studies have underscored the function of microRNAs (miRNAs) in THCA. Nevertheless, knowledge regarding the effects of exosomal miRNAs in THCA is still limited. This report intended to probe the regulatory effects of exosomal miR-152 on THCA and the underlying mechanism.

METHODS

The expression profile of miR-152 was studied in clinical samples as well as B-CPAP and TPC-1 cells. Transwell, CCK-8, and flow cytometric assays were performed to investigate the roles of miR-152 on invasion, migration, proliferation, and apoptosis in B-CPAP and TPC-1 cells. The putative target of miR-152 was predicted using the bioinformatic analysis, and the targeting relationship was confirmed verified subsequently. Afterward, exosomes were isolated from bone marrow mesenchymal stem cells (BM-MSCs) and co-cultured with B-CPAP and TPC-1 cells to explore the function of exosomal miR-152 on THCA cells.

RESULTS

miR-152 was reduced in THCA tissues and cells. Restoration of miR-152 inhibited proliferation, invasion and migration of B-CPAP and TPC-1 cells, but promoted cell apoptosis. Dipeptidyl dipeptidase 4 (DPP4), a target of miR-152, was found to promote THCA cell invasion and migration. miR-152 ferried by BM-MSCs-derived exosomes repressed THCA cell invasion and migration, and pcDNA-DPP4 weakened the repression effect.

CONCLUSION

Exosomal miR-152 inhibited proliferation, migration and invasion of THCA cells by binding with DPP4, which may represent a novel target for the treatment of THCA.

Diabetic Control Agents and Their Impact on Cardiac Surgery Patients: A Clinical Overview

Chronic hyperglycemia is associated with poor cardiovascular surgical outcomes due to microvascular and macrovascular complications. This is a major concern as over one third of cardiovascular surgical patients have diabetes mellitus which greatly increases their risk of experiencing adverse cardiovascular events. A literature review was performed to identify articles discussing the effects of anti-diabetic medications (ADMs) on cardiovascular outcomes and surgical mortality and morbidity rates. Optimizing perioperative glucose levels remains a key factor in producing good surgical outcomes. In addition, recognizing gender differences, increasing patient satisfaction, and implementing dedicated diabetic teams all improve surgical mortality and morbidity rates in the diabetic population.

Effects of antidiabetic medications on cardiovascular outcomes

OBJECTIVES

Hyperglycemia is associated with an increased risk of adverse cardiovascular outcomes, such as heart failure, coronary heart disease, stroke, and in-hospital mortality. For those receiving cardiac surgery, up to half develop hyperglycemia while 30% have a diagnosis of diabetes, which is defined by chronic hyperglycemia. Due to a prothrombic state and endovascular damage, patients with diabetes have a twofold increased risk of cardiovascular events.

METHODS

Electronic literature search was done to identify articles that have discussed antidiabetic medications and how it is impacting the glycemia status as well as cardiovascular outcomes. No limits were placed on timing of the publication or type of the article. Key words and MeSH terms were used to conduct the search and the results are summarized in a narrative manner within each relevant section.

RESULTS

Antidiabetic medications play a key role in lowering blood glucose levels to reduce adverse cardiovascular outcomes. However, it is a challenge to assess their cardiovascular safety due to confounding factors, such as age, obesity, smoking, hyperlipidemia, and high blood pressure. Further research in this field is required to understand this correlation closely.

CONCLUSION

Optimizing blood glucose level during the perioperative period with correct medication and dose have a significant role in reducing morbidities. Measures should be taken to provide a safe blood glucose level for optimum outcomes.

Is DPP4 inhibition a comrade or adversary in COVID-19 infection

Hypertension and Diabetes are the most common comorbid conditions in patients with COVID-19 and has been shown to adversely impact prognosis globally. It has been shown that hyperglycemia is one of the factors that increases the risk of poor outcomes in these patients. These patients are usually on multiple medications and recently a series of discussion on how Dipeptidyl peptidase 4 inhibitors (DPP4i) may be beneficial in these patients has been presented. This commentary presents a nuanced debateon why the DPP4i may not bebeneficial in COVID-19 and that caution needs to be addressed in making any judgementsuntil real world data is available.

Dipeptidyl Peptidase-4 at the Interface Between Inflammation and Metabolism

Dipeptidyl peptidase-4 (DPP4) is a serine protease that rapidly inactivates the incretin peptides, glucagon-like peptide-1, and glucose-dependent insulinotropic polypeptide to modulate postprandial islet hormone secretion and glycemia. Dipeptidyl peptidase-4 also has nonglycemic effects by controlling the progression of inflammation, which may be mediated more through direct protein-protein interactions than catalytic activity in the context of nonalcoholic fatty liver disease (NAFLD), obesity, and type 2 diabetes (T2D). Failure to resolve inflammation resulting in chronic subclinical activation of the immune system may influence the development of metabolic dysregulation. Thus, through both its cleavage and regulation of the bioactivity of peptide hormones and its influence on inflammation, DPP4 exhibits a diverse array of effects that can influence the progression of metabolic disease. Here, we highlight our current understanding of the complex biology of DPP4 at the intersection of inflammation, obesity, T2D, and NAFLD. We compare and review new mechanisms identified in basic laboratory and clinical studies, which may have therapeutic application and relevance to the pathogenesis of obesity and T2D.

Elevated circulating CD14++CD16+ intermediate monocytes are independently associated with extracardiac complications after cardiac surgery

Elective cardiac surgery has low procedural complications. However, about 40% of patients develop extracardiac complications including delirium and acute kidney injury. We hypothesized that inflammatory processes and immune cell activation might be associated with these complications. We therefore prospectively included 104 patients undergoing cardiac surgery in our study. We assessed peripheral blood leukocyte populations by flow cytometry and circulating cytokines before operation, after surgery and at days one and four post-operatively. Patients undergoing cardiac surgery showed significantly elevated leukocytes and neutrophils after surgery. On the contrary, monocytes decreased after surgery and significantly increased at days 1 and 4, particularly classical (Mon1,CD14++CD16−) and intermediate (Mon2,CD14++CD16+) monocytes. While peripheral leukocyte subsets were unaltered in patients with infectious (n = 15) or cardiac complications (n = 31), post-operative leukocytes (p = 0.0016), neutrophils (p = 0.0061) and Mon2 (p = 0.0007) were clearly raised in patients developing extracardiac complications (n = 35). Using multiple logistic regression analyses, patient’s age, ICU days, number of blood transfusions and elevated post-surgery Mon2 independently predicted extracardiac complications. Our findings demonstrate that elevated Mon2 after cardiac surgery are associated with an increased risk for extracardiac complications. These findings might improve the risk estimation after cardiac operations and the role of Mon2 for inflammation in cardiac surgery.

miR-29a inhibits proliferation, invasion, and migration of papillary thyroid cancer by targeting DPP4

Purpose: The purpose of this study was to investigate the effects of miR-29a on papillary thyroid cancer (PTC) and its underlying mechanisms.

Methods: Primary tumor tissues and adjacent tissues of 69 patients with PTC were obtained. Human thyroid cell line Nthy-ori3-1 and PTC cell lines K1, BCPAP, TPC-1 were cultured. K1 cells were transfected and divided into following groups: blank group (without any treatment), miR-29a mimics group, control mimics group, miR-29a inhibitor group, control inhibitor group, DPP4 siRNA group, control siRNA group and miR-29a inhibitor + DPP4 siRNA group. qRT-PCR and Western blot were used to detect miR-29a and DPP4 expression. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and transwell assay were performed to detect cells proliferation, migration, and invasion. A nude mice xenograft experiment was performed.

Results: miR-29a was significantly downregulated in PTC tissues, K1 and TPC-1 cells (P<0.01). DPP4 was significantly upregulated in the miR-29a inhibitor group and significantly downregulated in the miR-29a mimics group (P<0.01). DPP4 was the target gene of miR-29a. miR-29a significantly inhibited K1 cell proliferation, invasion, migration and PTC growth in nude mice by targeting DPP4 (P<0.01).

Conclusion: miR-29a inhibits proliferation, migration, and invasion of PTC by targeting DPP4, which might provide a new target for clinical treatment of PTC.