Platelet function in patients with diabetes mellitus: from a theoretical to a practical perspective

A circle of life: platelet and megakaryocyte cytoskeleton dynamics in health and disease

Platelets are blood cells derived from megakaryocytes that play a central role in regulating haemostasis and vascular integrity. The microtubule cytoskeleton of megakaryocytes undergoes a critical dynamic reorganization during cycles of endomitosis and platelet biogenesis. Quiescent platelets have a discoid shape maintained by a marginal band composed of microtubule bundles, which undergoes remarkable remodelling during platelet activation, driving shape change and platelet function. Disrupting or enhancing this process can cause platelet dysfunction such as bleeding disorders or thrombosis. However, little is known about the molecular mechanisms underlying the reorganization of the cytoskeleton in the platelet lineage. Recent studies indicate that the emergence of a unique platelet tubulin code and specific pathogenic tubulin mutations cause platelet defects and bleeding disorders. Frequently, these mutations exhibit dominant negative effects, offering valuable insights into both platelet disease mechanisms and the functioning of tubulins. This review will highlight our current understanding of the role of the microtubule cytoskeleton in the life and death of platelets, along with its relevance to platelet disorders.

Impact of Pretransplant C-Reactive Protein, Neutrophiles, Platelets, and Albumin Levels on Recipient Survival After Simultaneous Pancreas and Kidney Transplantation

BACKGROUND

Long-lasting diabetes mellitus type 1 and end-stage renal disease induce severe metabolic and immunologic deterioration. Pretransplant C-reactive protein (CRP) and albumin (ALB) levels impact kidney transplantation. We evaluated the effects of preoperative CRP, ALB, neutrophils (NEU), and platelet (PLT) counts on 1- and 5-year recipient survival after simultaneous pancreas and kidney transplantation (SPK).

METHODS

Among 103 SPK recipients, the parameters were as follows: CRP (mean: 4.5 ± 4.97 mg/L); NEU (mean: 5.12 ± 2.13 × 103/mm3); PLT (mean: 244 ± 84 × 103/mm3); ALB (mean 4.5 ± 0.75 g/dL) were obtained before transplantation. Cox regression, uni-, multivariate analysis for 1- and 5-year survivals were performed with 95% CIs, and the area under the receiver operating characteristic (ROC) curve (AUC) was assessed.

RESULTS

In Cox regression, ALB <3.65 g/dL significantly affected 1- and 5-year survivors with hazard ratios of 8 (95% CI, 1.5-38.28; P < .05) and 3.13 (95% CI, 1.45-6.73; P < .05), respectively. In univariate analysis, we found significantly decreased 1-year survival when PLT <180×103/mm3, ALB <3.65 g/dL, NEU >5.8×103/mm3 and CRP >2.25 mg/L with odds ratios (OR) of 6.75 (95% CI, 2.12-21.15); 4.05 (95% CI, 1.3-12.09); 2.97 (95% CI, 1.02-8.64) and 5.51 (95% CI, 1.67-18.19), respectively. Independent factors for 5-year survival were CRP, ALB, and PLT with OR of 4.72 (95% CI, 1.67-13.29), 3.31 (95% CI, 1.18-9.25), and 4.2 (95% CI, 1.39-12.68), respectively. In multivariate analysis, we built 2 models for 1-year survival. Model 1 (ALB+PLT) with ORs of 3.12 (95% CI, 0.97-10.07) and 5.55 (95% CI, 1.67-18.4); and model 2 (CRP+PLT) with ORs of 5.51 (95% CI, 1.5-17.3) and 4.3 (95% CI, 1.2-15.06), respectively. The AUC for models 1 and 2 were 0.74 and 0.759, respectively.

CONCLUSIONS

NEU, PLT, ALB, and CRP levels assessed before transplantation are independent factors for 1- and 5-year SPK recipient survival.

Relative Thrombus Burden Ratio Reveals Overproportioned Intraluminal Thrombus Growth-Potential Implications for Abdominal Aortic Aneurysm

Background: An intraluminal, non-occlusive thrombus (ILT) is a common feature in an abdominal aortic aneurysm (AAA). This study investigated the relative progression of ILT vs. AAA volume using a novel parameter, the so-called thrombus burden ratio (TBR), in non-treated AAAs. Parameters potentially associated with TBR progression were analyzed and TBR progression in large vs. small and fast- vs. slow-growing AAAs was assessed. Methods: This retrospective, single-center study analyzed sequential contrast-enhanced computed tomography angiography (CTA) scans between 2009 and 2018 from patients with an AAA before surgical treatment. Patients' medical data and CTA scans were analyzed at two given time points. The TBR was calculated as a ratio of ILT and AAA volume, and relative TBR progression was calculated by normalization for time between sequential CTA scans. Spearman's correlation was applied to identify morphologic parameters correlating with TBR progression, and multivariate linear regression analysis was used to evaluate the association of clinical and morphological parameters with TBR progression. Results: A total of 35 patients were included. The mean time between CT scans was 16 ± 15.9 months. AAA volume progression was 12 ± 3% and ILT volume progression was 36 ± 13%, resulting in a TBR progression of 11 ± 4%, suggesting overproportioned ILT growth. TBR progression was 0.8 ± 0.8% per month. Spearman's correlation verified ILT growth as the most relevant parameter contributing to TBR progression (R = 0.51). Relative TBR progression did not differ significantly in large vs. small and fast- vs. slow-growing AAAs. In the multivariate regression analysis, none of the studied factors were associated with TBR progression. Conclusion: TBR increases during AAA development, indicating an overproportioned ILT vs. AAA volume growth. The TBR may serve as a useful parameter, as it incorporates the ILT volume growth relative to the AAA volume, therefore combining two important parameters that are usually reported separately. Yet, the clinical relevance in helping to identify potential corresponding risk factors and the evaluation of patients at risk needs to be further validated in a larger study cohort.

Estimated Intake of Potassium, Phosphorus and Zinc with the Daily Diet Negatively Correlates with ADP-Dependent Whole Blood Platelet Aggregation in Older Subjects

The aggregation of blood platelets is the pivotal step that leads to thrombosis. The risk of thrombotic events increases with age. Available data suggest that minerals taken with diet can affect the course of thrombosis. However, little is known about the relationship between platelet aggregability and mineral intake with diet among elderly people. Thus, we evaluated the associations between the reactivities of platelets to arachidonic acid, collagen or ADP and the estimated quantities of minerals consumed as a part of the daily diet in 246 subjects aged 60-65 years (124 men and 122 women). The found simple (not-adjusted) Spearman's rank negative correlations are as follows: 1. arachidonate-dependent aggregation and the amounts of potassium, zinc, magnesium, phosphorus, iron, copper and manganese; 2. collagen-dependent aggregation and the amounts of potassium, phosphorus, iron and zinc; and 3. ADP-dependent aggregation and the amounts of potassium, phosphorus and zinc. The negative associations between ADP-dependent platelet reactivity and the amount of potassium, phosphorus and zinc and between collagen-dependent aggregability and the amount of phosphorus were also noted after adjusting for a bunch of cardiovascular risk factors. Overall, in older subjects, the intake of minerals with diet is negatively related to blood platelet reactivity, especially in response to ADP. Diet fortification with some minerals may possibly reduce the thrombotic risk among elderly patients.

Acute Antiplatelet Effects of an Oleocanthal-Rich Olive Oil in Type II Diabetic Patients: A Postprandial Study

Postprandial dysmetabolism is a common entity of type 2 diabetes mellitus (T2DM) and may act as a daily stressor of the already dysfunctional diabetic platelets. This study aims to investigate whether oleocanthal-rich olive oils (OO), incorporated into a carbohydrate-rich meal, can affect postprandial dysmetabolism and platelet aggregation. Oleocanthal is a cyclooxygenase inhibitor with putative antiplatelet properties. In this randomized, single-blinded, crossover study, ten T2DM patients consumed five isocaloric meals containing 120 g white bread combined with: (i) 39 g butter, (ii) 39 g butter and 400 mg ibuprofen, (iii) 40 mL OO (phenolic content < 10 mg/Kg), (iv) 40 mL OO with 250 mg/Kg oleocanthal and (v) 40 mL OO with 500 mg/Kg oleocanthal. Metabolic markers along with ex vivo ADP- and thrombin receptor-activating peptide (TRAP)-induced platelet aggregation were measured before and for 4 h after the meals. The glycemic and lipidemic response was similar between meals. However, a sustained (90-240 min) dose-dependent reduction in platelets' sensitivity to both ADP (50-100%) and TRAP (20-50%) was observed after the oleocanthal meals in comparison to OO or butter meals. The antiplatelet effect of the OO containing 500 mg/Kg oleocanthal was comparable to that of the ibuprofen meal. In conclusion, the consumption of meals containing oleocanthal-rich OO can reduce platelet activity during the postprandial period, irrespective of postprandial hyperglycemia and lipidemia.

Dysregulated coagulation system links to inflammation in diabetic kidney disease

Diabetic kidney disease (DKD) is a significant contributor to end-stage renal disease worldwide. Despite extensive research, the exact mechanisms responsible for its development remain incompletely understood. Notably, patients with diabetes and impaired kidney function exhibit a hypercoagulable state characterized by elevated levels of coagulation molecules in their plasma. Recent studies propose that coagulation molecules such as thrombin, fibrinogen, and platelets are interconnected with the complement system, giving rise to an inflammatory response that potentially accelerates the progression of DKD. Remarkably, investigations have shown that inhibiting the coagulation system may protect the kidneys in various animal models and clinical trials, suggesting that these systems could serve as promising therapeutic targets for DKD. This review aims to shed light on the underlying connections between coagulation and complement systems and their involvement in the advancement of DKD.

Effect of oral versus parenteral vitamin D3 supplementation on nuclear factor-κB and platelet aggregation in type 2 diabetic patients

Platelet hyperactivity is one of the key factors implicated in the development and progression of diabetic vascular complications. Activated platelets mediate leukocyte recruitment that further enhances inflammatory responses in vascular wall ultimately resulting in atherosclerotic complications. Since vitamin D insufficiency is highly prevalent in diabetics, we aimed to evaluate the effect of three dosage forms of vitamin D supplementation on lipid profile, NF-κB, platelet aggregation, and platelet calcium content in type 2 diabetic patients. Type 2 diabetic patients were randomized to receive daily (4000 IU/day) or weekly (50 000 IU/week) oral vitamin D3 for 3 months. Another group received a single parenteral dose (300 000 IU) of vitamin D3, whereas the control group received their antidiabetic drug(s) alone. Serum 25(OH)D, total cholesterol, triglycerides, high- and low-density lipoprotein cholesterol, NF-κB, and platelet aggregation were measured at the beginning and 3 months after vitamin D supplementation. Platelet calcium content was evaluated by measuring the fluorescence intensity of Rhod-2-stained platelets by confocal fluorescence microscopy. Results showed that serum 25(OH)D3 levels significantly increased in all vitamin D3-treated groups. However, the mean level for parenteral treated group was significantly lower than oral-treated groups. Oral and parenteral treatment were also able to decrease NF-κB level, platelet aggregation, and platelet calcium content. However, both oral doses of vitamin D3 were superior to the single parenteral dose. In conclusion, restoring normal levels of vitamin D is an important determinant to maintain normal platelet function and reduce inflammation. Nevertheless, further long-term studies are still needed.

Insulin Resistance-Induced Platelet Hyperactivity and a Potential Biomarker Role of Platelet Parameters: A Narrative Review

Background

Insulin has an inhibitory effect on platelets; however, this is compromised in circumstances of Insulin Resistance (IR), leading to platelet hyperactivity. Platelet parameters such as mean platelet volume, platelet count, and platelet distribution width are simple and accessible potential biomarkers for the early diagnosis and prognosis of IR. Therefore, the aim of this review is to provide insight on the current status of knowledge regarding IR-induced platelet hyperactivation and the potential biomarker role of platelet parameters.

Methods

This narrative review included articles published in the English language. Searches were carried out at the electronic databases PubMed and Google Scholar. The search strategy was done by combining key words and related database-specific subject terms (Mesh terms) with the appropriate Boolean operators.

Conclusion

Increasing insulin sensitivity in insulin resistant patients would possibly cause substantial reduction in platelet activation, which in turn reduce complications related with platelet hyperactivation. The standard methods to measure IR are not frequently employed in clinical practice due to their expensiveness and complexity. Thus, early detection of IR using a simple and more widely available biomarkers such as mean platelet volume, platelet count and platelet distribution width would be beneficial. Particularly in developing countries where resource scarcity is a major constraint of the health sector, utilizing such easy and affordable biomarkers may have a crucial role.

Pharmacokinetic and Pharmacodynamic Interactions Between Henagliflozin, a Novel Selective SGLT-2 Inhibitor, and Warfarin in Healthy Chinese Subjects

PURPOSE

While controlling blood glucose, patients with diabetes and abnormal coagulation should be treated with positive anticoagulation because the hypercoagulable state of their blood is the primary cause of macroangiopathy. The goal of this study was to evaluate the pharmacokinetic and pharmacodynamic (PK/PD) interactions between henagliflozin, a novel selective sodium-glucose cotransporter 2 inhibitor, and warfarin in healthy subjects.

METHODS

This single-center, open-label, single-arm clinical study was conducted in 16 healthy male Chinese subjects. According to the study protocol, the PK properties of henagliflozin 10 mg/d and warfarin 5 mg/d were collected and tabulated in accordance with sampling time. All study drugs were given with once-daily administration. Subjects were monitored for adverse reactions and their severity, outcomes, and relationship to study drug. This influences of warfarin on the PK properties of henagliflozin (Cmax,ss and AUCτ,ss), the effects of henagliflozin on the PK properties of warfarin (Cmax, AUC0-t, and AUC0-∞), and the influences of henagliflozin on the PD properties of warfarin (PTmax, PTAUC, INRmax, and INRAUC) were evaluated.

FINDINGS

The geometric mean ratios (GMRs; 90% CIs) of henagliflozin Cmax,ss and AUCτ,ss were 101.75% (96.11%-107.72%) and 102.21% (100.04%-104.42%), respectively. The GMRs (90% CIs) of S- and R-warfarin Cmax, AUC0-t, and AUC0-∞ were as follows: Cmax, 114.31% (106.30%-122.91%) and 115.09% (109.46%-121.01%), respectively; AUC0-t, 120.15% (116.71%-123.69%) and 119.01% (116.32%-121.76%); and AUC0-∞, 120.81% (117.17%-124.58%) and 121.94% (118.90%-125.05%). The GMRs (90% CIs) of warfarin PTmax and PTAUC were 92.73% (91.25%-94.22%) and 97.42% (96.61%-98.24%). The GMRs (90% CIs) of warfarin INRmax and INRAUC were 92.66% (91.17%-94.17%) and 97.36% (96.52%-98.21%). A total of 32 cases of mild adverse events were reported, and were recovered/resolved. There were no serious adverse events reported.

IMPLICATIONS

No significant clinically relevant effects on the PK/PD properties of henagliflozin or warfarin were found with coadministration of the two drugs in these healthy male Chinese subjects. Based on these findings, it is expected that henagliflozin and warfarin can be used in combination without dose adjustment. Chinadrugtrials.org.cn identifier: CTR20190240.

Platelet Glycoprotein-Ib (GPIb) May Serve as a Bridge between Type 2 Diabetes Mellitus (T2DM) and Atherosclerosis, Making It a Potential Target for Antiplatelet Agents in T2DM Patients

Type 2 diabetes mellitus (T2DM) is a persistent metabolic condition that contributes to the development of cardiovascular diseases. Numerous studies have provided evidence that individuals with T2DM are at a greater risk of developing cardiovascular diseases, typically two to four times more likely than those without T2DM, mainly due to an increased risk of atherosclerosis. The rupture of an atherosclerotic plaque leading to pathological thrombosis is commonly recognized as a significant factor in advancing cardiovascular diseases caused by TD2M, with platelets inducing the impact of plaque rupture in established atherosclerosis and predisposing to the primary expansion of atherosclerosis. Studies suggest that individuals with T2DM have platelets that display higher baseline activation and reactivity than those without the condition. The expression enhancement of several platelet receptors is known to regulate platelet activation signaling, including platelet glycoprotein-Ib (GPIb). Furthermore, the high expression of platelet GP1b has been reported to increase the risk of platelet adhesion, platelet-leucocyte interaction, and thrombo-inflammatory pathology. However, the study exploring the role of GP1b in promoting platelet activation-induced cardiovascular diseases in T2DM patients is still limited. Therefore, we summarize the important findings regarding pathophysiological continuity between T2DM, platelet GPIb, and atherosclerosis and highlight the potential therapy targeting GPIb as a novel antiplatelet agent for preventing further cardiovascular incidents in TD2M patients.

Structure-Activity Relationship Analysis of Rhosin, a RhoA GTPase Inhibitor, Reveals a New Class of Antiplatelet Agents

Current antiplatelet therapies have several clinical complications and are mostly irreversible in terms of suppressing platelet activity; hence, there is a need to develop improved therapeutic agents. Previous studies have implicated RhoA in platelet activation. Here, we further characterized the lead RhoA inhibitor, Rhosin/G04, in platelet function and present structure-activity relationship (SAR) analysis. A screening for Rhosin/G04 analogs in our chemical library by similarity and substructure searches revealed compounds that showed enhanced antiplatelet activity and suppressed RhoA activity and signaling. A screening for Rhosin/G04 analogs in our chemical library using similarity and substructure searches revealed compounds that showed enhanced antiplatelet activity and suppressed RhoA activity and signaling. SAR analysis revealed that the active compounds have a quinoline group optimally attached to the hydrazine at the 4-position and halogen substituents at the 7- or 8-position. Having indole, methylphenyl, or dichloro-phenyl substituents led to better potency. Rhosin/G04 contains a pair of enantiomers, and S-G04 is significantly more potent than R-G04 in inhibiting RhoA activation and platelet aggregation. Furthermore, the inhibitory effect is reversible, and S-G04 is capable of inhibiting diverse-agonist-stimulated platelet activation. This study identified a new generation of small-molecule RhoA inhibitors, including an enantiomer capable of broadly and reversibly modulating platelet activity.

Is Triglyceride-Glucose Index a Valuable Parameter in Peripheral Artery Disease?

Background The aim of this study was to investigate the relationship between the triglyceride-glucose (TyG) index and peripheral artery disease. Methodology This was a single-center, observational, retrospective study that included patients evaluated with color Doppler ultrasonography. A total of 440 individuals, 211 peripheral artery patients and 229 healthy controls, were included in the study. Results The TyG index levels were significantly higher in the peripheral artery disease group than in the control group (9.19 ± 0.57 vs. 8.80 ± 0.59; p < 0.001). The multivariate regression analysis conducted to determine the independent predictors of peripheral artery disease revealed that age (odds ratio (OR) = 1.111, 95% confidence interval (CI) = 1.083-1.139; p < 0.001), male gender (OR = 0.441, 95% CI = 0.249-0.782; p = 0.005), diabetes mellitus (OR = 1.925, 95% CI = 1.018-3.641; p = 0.044), hypertension (OR = 0.036, 95% CI = 0.285- 0.959; p = 0.036), coronary artery disease (OR = 2.540, 95% CI = 1.376-4.690; p = 0.003), white blood cell count (OR = 1.263, 95% CI = 1.029-1.550; p = 0.026), creatinine (OR = 0.975, 95% CI = 0.952-0.999; p = 0.041), and TyG index (OR = 1.111, 95% CI = 1.083-1.139; p < 0.001) were independent predictors of peripheral artery disease. The cut-off value of the TyG index in predicting peripheral artery disease was determined to be 9.06 with a sensitivity of 57.8% and a specificity of 70% (area under the curve = 0.689; 95% CI = 0.640-0.738; p < 0.001). Conclusions High TyG index values can be used as an independent predictor of peripheral artery disease.

The impact of SGLT2-inhibitor therapy on platelet function in type 2 diabetes mellitus

Aim: We consider mean platelet volume (MPV), an a pointer of platelet activity related to type 2 diabetes mellitus (T2DM) and vascular complications, in patients using Sodium-Glucose Co-Transporter 2 inhibitors (SGLT2i). Therefore, we aimed to evaluate the MPV change after SGLT2i use in diabetic patients. Materials and Methods: Hemogram parameters such as hemoglobin, hematocrit, and MPV in the 0th and 24th weeks of 102 patients with T2DM that received SGLT2i treatment added to their existing medications and of the control group in which participants are compatible in terms of age and gender factor were compared. Results: A significant increase was observed in the values of MPV and hemoglobin in the 0th and 24th weeks (9.3 (8.2-10.3) to 10.1 ± 1.3, p

Type 2 Diabetes Mellitus, Platelet Activation and Alzheimer's Disease: A Possible Connection

Type 2 diabetes mellitus DM (T2DM) is associated with a 70% increased risk for dementia, including Alzheimer's disease (AD). Insulin resistance has been proposed to play a pivotal role in both T2DM and AD and the concept of "brain insulin resistance" has been suggested as an interpretation to the growing literature regarding cognitive impairment and T2DM. Subjects with T2DM present an abnormal platelet reactivity that together with insulin resistance, hyperglycaemia and dyslipidaemia effect the vascular wall by a series of events including endothelial dysfunction, oxidative stress and low-grade inflammation. Activated platelets directly contribute to cerebral amyloid angiopathy (CAA) by promoting the formation of β-amyloid (Aβ) aggregates and that Aβ, in turn, activates platelets, creating a feed-forward loop suggesting the involvement of platelets in the AD pathogenesis. Moreover, islet amyloid polypeptide deposition, co-localized with Aβ deposits, is a common finding in the brain of patients with T2DM. These observations raise the intriguing prospect that traditional or novel antiplatelet therapeutic strategies may alleviate fibril formation and could be used in the prevention or treatment of AD subjects with diabetes.

The role of the platelet pool of Plasminogen Activator Inhibitor-1 in well-controlled type 2 diabetes patients

Background

The main inhibitor of the fibrinolytic system, Plasminogen Activator Inhibitor -1 (PAI-1), irreversibly binds tissue-type Plasminogen Activator (t-PA) and thereby inhibits the protective action of tPA against thrombus formation. Elevated levels of plasma PAI-1 are associated with an increased risk of cardiovascular events and are observed in subjects with type 2 diabetes (T2D) and obesity. Platelets contain the majority of PAI-1 present in blood and exhibit the ability to synthesis active PAI-1. Diabetic platelets are known to be hyper-reactive and larger in size; however, whether these features affect their contribution to the elevated levels of plasma PAI-1 in T2D is not established.

Objectives

To characterize the PAI-1 antigen content and the mRNA expression in platelets from T2D subjects compared to obese and lean control subjects, in order to elucidate the role of platelet PAI-1 in T2D.

Methods

Nine subjects with T2D and obesity were recruited from Primary Care Centers together with 15 healthy control subjects (8 lean subjects and 7 with obesity). PAI-1 antigen levels in plasma, serum and platelets were determined by ELISA, and PAI-1 mRNA expression was analyzed by qPCR.

Results

There was no significant difference in PAI-1 mRNA expression or PAI-1 antigen in platelets in T2D subject in comparison to obese and lean control subjects. An elevated level of plasma PAI-1 was seen in both T2D and obese subjects. PAI-1 gene expression was significantly higher in both obese groups compared to lean.

Conclusion

Similar levels of protein and mRNA expression of PAI-1 in platelets from T2D, obese and lean subjects indicate a limited role of platelets for the elevated plasma PAI-1 levels. However, an increased synthesis rate of mRNA transcripts in platelets from T2D and an increased release of PAI-1 could also result in similar mRNA and protein levels. Hence, synthesis and release rates of PAI-1 from platelets in T2D and obesity need to be investigated to further elucidate the role of platelets in obesity and T2D.

Relationship between the Soluble F11 Receptor and Annexin A5 in African Americans Patients with Type-2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is characterized by endothelial dysfunction, increased thrombogenicity, and inflammation. The soluble human F11 receptor (sF11R) and annexin A5 (ANXA5) play crucial roles in inflammatory thrombosis and atherosclerosis. We examined the relationship between circulating sF11R and ANXA5 and their impact on endothelial function. The study included 125 patients with T2DM. Plasma levels of sF11R and ANXA5 were quantified by ELISA. Microvascular function was assessed using the vascular reactivity index (VRI). Large artery stiffness was assessed by carotid-femoral pulse wave velocity (PWV). Carotid intima-media thickness (CIMT) was assessed by B-mode ultrasound imaging. The mean age of patients in the study was 59.7 ± 7.8 years, 78% had hypertension, 76% had dyslipidemia, and 12% had CKD. sF11R correlated positively with ANXA5 levels (β = 0.250, p = 0.005), and correlated inversely with VRI and total nitic oxide (NO), (β = −0.201, p = 0.024; β = −0.357, p = 0.0001, respectively). Multivariate regression analysis revealed that sF11R was independently associated with ANXA5 in the total population and in patients with HbA1c > 6.5% (β = 0.366, p = 0.007; β = 0.425, p = 0.0001, respectively). sF11R and ANXA5 were not associated with vascular outcome, suggesting that they may not be reliable markers of vascular dysfunction in diabetes. The clinical significance of sF11R/ANXA5 association in diabetes warrants further investigation in a larger population.

The Role of Platelets in Diabetic Kidney Disease

Diabetic kidney disease (DKD) is among the most common microvascular complications in patients with diabetes, and it currently accounts for the majority of end-stage kidney disease cases worldwide. The pathogenesis of DKD is complex and multifactorial, including systemic and intra-renal inflammatory and coagulation processes. Activated platelets play a pivotal role in inflammation, coagulation, and fibrosis. Mounting evidence shows that platelets play a role in the pathogenesis and progression of DKD. The potentially beneficial effects of antiplatelet agents in preventing progression of DKD has been studied in animal models and clinical trials. This review summarizes the current knowledge on the role of platelets in DKD, including the potential therapeutic effects of antiplatelet therapies.

Bias or biology? Importance of model interpretation in machine learning studies from electronic health records

Objective

The rate of diabetic complication progression varies across individuals and understanding factors that alter the rate of complication progression may uncover new clinical interventions for personalized diabetes management.

Materials and Methods

We explore how various machine learning (ML) models and types of electronic health records (EHRs) can predict fast versus slow onset of neuropathy, nephropathy, ocular disease, or cardiovascular disease using only patient data collected prior to diabetes diagnosis.

Results

We find that optimized random forest models performed best to accurately predict the diagnosis of a diabetic complication, with the most effective model distinguishing between fast versus slow nephropathy (AUROC = 0.75). Using all data sets combined allowed for the highest model predictive performance, and social history or laboratory alone were most predictive. SHapley Additive exPlanations (SHAP) model interpretation allowed for exploration of predictors of fast and slow complication diagnosis, including underlying biases present in the EHR. Patients in the fast group had more medical visits, incurring a potential informed decision bias.

Discussion

Our study is unique in the realm of ML studies as it leverages SHAP as a starting point to explore patient markers not routinely used in diabetes monitoring. A mix of both bias and biological processes is likely present in influencing a model’s ability to distinguish between groups.

Conclusion

Overall, model interpretation is a critical step in evaluating validity of a user-intended endpoint for a model when using EHR data, and predictors affected by bias and those driven by biologic processes should be equally recognized.

Peripheral Cytopenia and Its Associated Factors in Type 2 Diabetes Mellitus Patients, Northwest Ethiopia

Background

Hematological abnormalities are linked with diabetes mellitus (DM) and play a major role in diabetes-related micro- and macro-vascular complications. Therefore, this study aimed to investigate the magnitude of peripheral cytopenia and associated factors in type 2 diabetes (T2DM) patients.

Methods

A cross-sectional study was conducted from March to May 2021 at the University of Gondar Comprehensive Specialized Hospital. A total of 357 T2DM participants were selected using a simple random sampling technique. A total of 3 mL of venous blood samples were collected using the vacutainer method for the complete blood count (CBC). A univariate and multivariate regression analysis were used to investigate the association between dependent and independent variables. P-value ˂0.05 was considered statistically significant.

Results

The magnitude of cytopenia, bicytopenia, and pancytopenia were 21% (95% CI: 17.1, 25.53), 1.1% (95% CI: 0.44, 2.85), and 0.56% (95% CI: 0.01, 1.12), respectively. Furthermore, the magnitudes of anemia, leucopenia, and thrombocytopenia were 8.7% (95% CI: 6.18, 12.06), 10.9% (95% CI: 8.09, 14.59), and 5.3% (95% CI: 3.43, 8.16), respectively. Being male (AOR: 3.23; 95% CI: 1.43, 7.56), lack of exercise (AOR: 2.70; 95% CI: 1.137, 6.43), and never married (AOR: 3.90; 95% CI: 1.248, 12.18) were all associated with anemia.

Conclusion

This study showed that T2DM causes disturbances in the hematological parameters and leads to a mild level of cytopenia. It is, therefore, suggested that hematological abnormalities, especially cytopenia, should be monitored and controlled on a regular basis in T2DM patients for better prognosis and quality of life.

Mean platelet volume and glycaemic control in patients with new-onset Type 2 diabetes mellitus

Introduction:

Type 2 diabetes mellitus (T2DM) is a metabolic disorder associated with vascular complications that are attributable to dysregulated platelet reactivity as measured by mean platelet volume (MPV). This study aimed at determining a relationship between MPV and glycaemic control in new-onset T2DM.

Materials and methods:

This was a prospective study conducted on 236 new-onset T2DM patients divided in two groups as group A, glycosylated haemoglobin A1c (HbA1c < 7.9%; n = 70) and group B, HbA1c ⩾ 8% ( n = 107) who were followed up for 6 months for change in platelet and glycaemic parameters.

Results:

At 6-month follow-up, there was a significant decrease in HbA1c and MPV (group A (HbA1c: 7.40 ± 0.40 vs 7.03 ± 0.23%, p < 0.03; MPV: 9.65 fl ± 0.74 vs 9.46 fl ± 0.71, p < 0.001) and group B (HbA1c: 10.59 ± 1.89% vs 9.29 ± 1.50%, p < 0.001; MPV: 10.89 fL ± 1.29 vs. 10.23 fL ± 1.40, p< 0.001)). The percentage decline in HbA1c was more in group B (11.81 ± 5.87 vs 4.76 ± 4.58, p < 0.01). There was a positive correlation between ΔMPV and ΔHbA1c in group B; however, we did not observe significant correlation for group A.

Conclusion:

We interpret that in people with diabetes with baseline HbA1c ⩾ 8%, with improvement in glycaemic control, there is a significant decrease in MPV. We propose that a routine MPV testing can be used as a potential marker for glycaemic control in T2DM.

Vitamin D Supplementation Modulates Platelet-Mediated Inflammation in Subjects With Type 2 Diabetes: A Randomized, Double-Blind, Placebo-Controlled Trial

Background

Recently, our group identified increased platelet-mediated inflammation in type 2 diabetes (T2DM) patients, and it is a well-established risk factor for diabetes complications, particularly for the development of cardiovascular diseases (CVD). Furthermore, vitamin D is reported to play an important role in the modulation of platelet hyperactivity and immune function, although the effect of vitamin D on platelet-mediated inflammation is not well studied. Hence, we aimed to investigate the effect of vitamin D supplementation on platelet-mediated inflammation in T2DM patients.

Methods

After screening a total of 201 subjects, our randomized, double-blind, placebo-controlled trial included 59 vitamin-D-deficient T2DM subjects, and the participants were randomly assigned to placebo (n = 29) or vitamin D3 (n = 30) for 6 months. Serum vitamin D metabolite levels, immunome profiling, platelet activation, and platelet-immune cell aggregate formation were measured at baseline and at the end of the study. Similarly, the serum levels of inflammatory cytokines/chemokines were assessed by a multiplex assay.

Results

Six months of vitamin D supplementation increases the serum vitamin D3 and total 25(OH)D levels from the baseline (p < 0.05). Vitamin D supplementation does not improve glycemic control, and no significant difference was observed in immune cells. However, platelet activation and platelet immune cell aggregates were altered after the vitamin D intervention (p < 0.05). Moreover, vitamin D reduces the serum levels of IL-18, TNF-α, IFN-γ, CXCL-10, CXCL-12, CCL-2, CCL-5, CCL-11, and PF-4 levels compared to the baseline levels (p < 0.05). Our ex vivo experiment confirms that a sufficient circulating level of vitamin D reduces platelet activation and platelet intracellular reactive oxygen species.

Conclusion

Our study results provide evidence that vitamin D supportive therapy may help to reduce or prevent the disease progression and cardiovascular risk in T2DM patients by suppressing oxidative stress and platelet-mediated inflammation.

Clinical Trial Registration

Clinical Trial Registry of India: CTRI/2019/01/016921.

An Insight into Recent Advances on Platelet Function in Health and Disease

Platelets play a variety of roles in vascular biology and are best recognized as primary hemostasis and thrombosis mediators. Platelets have a large number of receptors and secretory molecules that are required for platelet functionality. Upon activation, platelets release multiple substances that have the ability to influence both physiological and pathophysiological processes including inflammation, tissue regeneration and repair, cancer progression, and spreading. The involvement of platelets in the progression and seriousness of a variety of disorders other than thrombosis is still being discovered, especially in the areas of inflammation and the immunological response. This review represents an integrated summary of recent advances on the function of platelets in pathophysiology that connects hemostasis, inflammation, and immunological response in health and disease and suggests that antiplatelet treatment might be used for more than only thrombosis.

Proteome and functional decline as platelets age in the circulation

BACKGROUND

Platelets circulate in the blood of healthy individuals for approximately 7-10 days regulated by finely balanced processes of production and destruction. As platelets are anucleate we reasoned that their protein composition would change as they age and that this change would be linked to alterations in structure and function.

OBJECTIVE

To isolate platelets of different ages from healthy individuals to test the hypothesis that changes in protein content cause alterations in platelet structure and function.

METHODS

Platelets were separated according to thiazole orange fluorescence intensity as a surrogate indicator of mRNA content and so a marker of platelet age and then subjected to proteomics, imaging, and functional assays to produce an in-depth analysis of platelet composition and function.

RESULTS

Total protein content was 45 ± 5% lower in old platelets compared to young platelets. Predictive proteomic pathway analysis identified associations with 28 biological processes, notably higher hemostasis in young platelets whilst apoptosis and senescence were higher in old platelets. Further studies confirmed platelet ageing was linked to a decrease in cytoskeletal protein and associated capability to spread and adhere, a reduction in mitochondria number, and lower calcium dynamics and granule secretion.

CONCLUSIONS

Our findings demonstrate changes in protein content are linked to alterations in function as platelets age. This work delineates physical and functional changes in platelets as they age and serves as a base to examine differences associated with altered mean age of platelet populations in conditions such as immune thrombocytopenia and diabetes.

Effect of irisin on metabolic and platelet functions in type 2 diabetic rats: role of soluble receptor of advanced glycation end products (sRAGE)

Background

Irisin is an adipomyokine with a promising potential for the treatment of metabolic disturbances and endothelial dysfunction. This study aimed to explore the effect of irisin on metabolic and platelet functions, and to explore the possible involvement of soluble receptor of advanced glycation end product (sRAGE) in the type 2 diabetes mellitus (T2DM) rat model. Thirty-three adult male albino rats were divided into three groups: normal control, vehicle-treated T2DM group, and irisin-treated T2DM. At the end of the study period, metabolic parameters, platelet count, mean platelet volume, platelet distribution width, plateletcrit, and serum sRAGE were determined.

Results

Irisin significantly improved platelet function and metabolic derangements induced by T2DM and significantly increased sRAGE. sRAGE was significantly negatively associated with platelet function parameters and some glucometabolic parameters. Additionally, mean platelet volume showed a significant predictive value for the change in serum sRAGE.

Conclusions

Irisin could have a protective role against diabetes-induced platelet dysfunction by increasing sRAGE levels, indicating the potential beneficial effects of sRAGE in the type 2 diabetic rat model.

Impact of Pancreatic β-Cell Function on Clopidogrel Responsiveness and Outcomes in Chinese Nondiabetic Patients Undergoing Elective Percutaneous Coronary Intervention

PURPOSE

Insulin resistance and β-cell dysfunction are fundamental defects contributing to type 2 diabetes development. Prior studies indicated that insulin resistance may be correlated with low responsiveness to clopidogrel. This study aimed to investigate the effects of β-cell function on clopidogrel-induced platelet P2Y12 inhibition and the clinical outcomes of nondiabetic patients undergoing elective percutaneous coronary intervention (PCI).

METHODS

Patients scheduled to undergo elective PCI and receive clopidogrel in addition to aspirin were recruited for this study. Homeostatic model assessment 2 of β-cell function (HOMA2-β%) was used to classify participants into quartiles. Thromboelastography (TEG) was used to calculate the quantitative platelet inhibition rate to assess clopidogrel-induced antiplatelet reactivity. The clinical outcome was major adverse cardiovascular and cerebrovascular events (MACCEs).

RESULTS

Of the 784 participants evaluated, 21.3% of them (169 of 784) had low responsiveness to clopidogrel. According to multivariate linear regression analysis, the first quartile of HOMA2-β% (19.9-78.1), indicating greater β-cell dysfunction, was independently associated with low responsiveness to clopidogrel compared with the fourth quartile (126.8-326.2) after adjustment for potential covariates [odds ratio 2.140, 95% confidence interval (CI) (1.336 to 3.570), P = 0.038]. In addition, at one year, the first quartile of HOMA2-β% was associated with an increased risk of 1-year MACCE occurrence compared with the fourth quartile [adjusted hazard ratio 4.989, 95% CI (1.571 to 15.845), P = 0.006].

CONCLUSION

Increased β-cell dysfunction, indicated by a low HOMA2-β%, was associated with low responsiveness to clopidogrel and an increased risk of one-year MACCEs in nondiabetic patients undergoing elective PCI.

Intravital assessment of precapillary pulmonary arterioles of type 1 diabetic mice shows oxidative damage and increased tone in response to NOS inhibition

Microvascular dilation, important for peripheral tissue glucose distribution, also modulates alveolar perfusion and is inhibited by loss of bioavailable nitric oxide (NO) in diabetes mellitus (DM). We hypothesized that DM-induced oxidative stress decreases bioavailable NO and pulmonary precapillary arteriolar diameter, causing endothelial injury. We examined subpleural pulmonary arterioles after acute NO synthase (NOS) inhibition with NG-nitro-l-arginine methyl ester (l-NAME) in streptozotocin (STZ)- and saline (CTRL)-treated C57BL/6J mice. Microvascular changes were assessed by intravital microscopy in the right lung of anesthetized mice with open chest and ventilated lungs. Arteriolar tone in pulmonary arterioles (27.2-48.7 µm diameter) increased in CTRL mice (18.0 ± 11% constriction, P = 0.034, n = 5) but decreased in STZ mice (13.6 ± 7.5% dilation, P = 0.009, n = 5) after l-NAME. Lung tissue dihydroethidium (DHE) fluorescence (superoxide), inducible NOS expression, and protein nitrosylation (3-nitrotyrosine) increased in STZ mice and correlated with increased glucose levels (103.8 ± 8.8 mg/dL). Fluorescently labeled fibrinogen administration and fibrinogen immunostaining showed fibrinogen adhesion, indicating endothelial injury in STZ mice. In CTRL mice, vasoconstriction to l-NAME was likely due to the loss of bioavailable NO. Vasodilation in STZ mice may be due to decreased formation of a vasoconstrictor or emergence of a vasodilator. These findings provide novel evidence that DM targets the pulmonary microcirculation and that decreased NO bioavailability and increased precapillary arteriolar tone could potentially lead to ventilation-perfusion abnormalities, exacerbating systemic DM complications.NEW & NOTEWORTHY Diabetes pulmonary and microvascular consequences are well recognized but have not been characterized. We assessed lung microvascular changes in a live anesthetized mouse model of type 1 diabetes, using a novel intravital microscopy technique. Our results show new evidence that a diabetes-induced decrease in lung nitric oxide bioavailability underlies oxidative damage, enhanced platelet activation, and endothelial injury causing pulmonary microvascular dysfunction and altered vasoreactivity. These findings could provide novel strategies to prevent or reverse diabetes systemic consequences.

Mean Platelet Volume is Associated with Pancreatic β-Cell Dysfunction in Nondiabetic Patients with Coronary Artery Disease

Purpose

Mean platelet volume (MPV) is an indicator of platelet activation. Pancreatic β-cell dysfunction is one of the fundamental defects contributing to the development of type 2 diabetes. The aim of this study was to assess the relationship between β-cell dysfunction and MPV in nondiabetic patients with coronary artery disease (CAD).

Patients and Methods

A total of 1143 consecutive nondiabetic patients (874 males and 269 females; mean age 60.0±10.3 years) with CAD were recruited for this analysis. All patients were individuals who underwent coronary angiography with a suspicion of CAD. Homeostatic model assessment 2 (HOMA2) of β-cell function (HOMA2-β%) was performed, and β-cell dysfunction was defined by a HOMA2-β% in the lowest quartile.

Results

MPV was significantly higher in CAD patients with β-cell dysfunction than in controls [(10.6±1.0)fl vs (10.0±1.0)fl, P=0.011]. According to the multiple regression model, pancreatic β-cell dysfunction was independently associated with MPV (β=0.210, P=0.006) and age (β=0.008, P=0.028).

Conclusion

MPV was significantly elevated in nondiabetic CAD patients with β-cell dysfunction compared to patients with normal β-cell function.

Platelet Mediated Inflammation in Coronary Artery Disease with Type 2 Diabetes Patients

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a well-established risk factor for the development of atherosclerotic coronary artery disease. Platelet hyperactivity and inflammation are associated with the development of coronary artery disease (CAD) in T2DM patients. We investigated the status of immune cells, platelet activation, and platelet-immune cell interactions in T2DM_CAD patients.

METHODOLOGY

The study population consisted of four groups of subjects, healthy control (CT, n = 20), T2DM (n = 44), CAD (n = 20) and T2DM_CAD (n = 38). Platelet activation, immunome profiling and platelet-immune cell interactions were analysed by flow cytometry. The circulatory levels of inflammatory cytokines/chemokines were assessed using multiplex assay.

RESULTS

Increased platelet activation and increased platelet-immune cell aggregate formation were observed in T2DM and T2DM_CAD groups compared to the control and CAD groups (p < 0.05). Our immunome profile analysis revealed, altered monocyte subpopulations and dendritic cell populations in T2DM, CAD and T2DM_CAD groups compared to the control group (p < 0.05). Furthermore, significantly increased IL-1β, IL-2, IL-4, IL-6, IL-8, IL12p70, IL-13 IL-18, CCL2, and decreased CXCL1, CCL5 levels were observed in T2DM_CAD group compared to the control group. Our ex-vivo study increased platelet-monocyte aggregate formation was observed upon D-glucose exposure in a time and concentration dependent manner.

CONCLUSION

Our data suggests that T2DM, CAD and T2DM_CAD are associated with altered immune cell populations. Furthermore, it has been confirmed that hyperglycemia induces platelet activation and forms platelet-immune cell aggregation which may lead to the release of inflammatory cytokines and chemokines and contribute to the complexity of CAD and type 2 diabetes.

Prognostic value of subclinical myocardial necrosis using high-sensitivity cardiac troponin T in patients with prediabetes

BACKGROUND

Risk stratification of patients with prediabetes is an unmet clinical need. Here, we examine the utility of subclinical myocardial necrosis assessed by high-sensitivity cardiac troponin T (hs-cTnT) in predicting health outcomes in stable subjects with prediabetes.

METHODS

hs-cTnT was analyzed by a high-sensitivity assay (Roche 5th generation) in 2631 stable subjects with prediabetes (HbA1c 5.7-6.4% or fasting glucose 100-125 mg/dL without previous diagnosis of diabetes or glucose-lowering therapy) who underwent elective coronary angiography for cardiac evaluation, and followed for major adverse cardiac events (MACE; death, myocardial infarction, stroke) over 3 years and all-cause mortality over 5 years.

RESULTS

In our study cohort, hs-cTnT was highly prevalent with a median level of 13 ng/L (interquartile range 8.2-21.6 ng/L). Hs-cTnT was independently associated with incident MACE at 3 years (Q4 vs. Q1 adjusted hazard ratio (HR) 2.42 [95% CI 1.69-3.46], P < 0.001) and 5-year mortality (adjusted HR 3.8 [95% CI 2.55-5.67], P < 0.001). This association remained significant in all subsets after adjustment for traditional risk factors and multiple factors known to increase hs-cTnT levels. Moreover, hs-cTnT independently predicted event risk in primary prevention subjects (n = 557, HR 5.46 [95% CI 1.50-19.89), p < 0.01) for MACE; HR 9.53 [95% CI 2.08-43.73] for all-cause mortality) and secondary prevention subjects (n = 2074, HR 1.86 [95% CI 1.31-2.66], P < 0.001 for MACE; and 2.7 [95% CI 1.79-4.08), P < 0.001 for all-cause mortality).

CONCLUSIONS

In stable prediabetic subjects, the presence of subclinical myocardial necrosis as detected by hs-cTnT portends heightened long-term adverse cardiovascular event risk. Hs-cTnT levels may help to stratify risk and improve clinical decision making in patients with prediabetes. Trial registration ClinicalTrials.gov Identifier: NCT00590200.

Long-term aerobic exercise training in type two diabetic patients alters the expression of miRNA-223 and its corresponding target, the P2RY12 receptor, attenuating platelet function

BACKGROUND

Type two diabetes mellitus (T2DM) patients are prone to develop atherothrombotic events due to platelet hyper-reactivity stemming from platelet miRNA-223 down-regulation and over-expression of its corresponding target, P2RY12.

OBJECTIVE

The study sought to determine the effects of long-term aerobic training on the expression levels of miRNA-223 and P2RY12 mRNA, and platelet function in T2DM patients.

METHODS

Twenty-four patients with T2DM (age, 60.0±2.8 yrs.) were selected and randomly divided into two groups: aerobic exercise training (AET, n = 12) and control (CON, n = 12). The AET protocol was performed with moderate intensity for 12 weeks, while patients in the CON group followed their usual routine. Weight, body mass index (BMI), peak oxygen consumption (VO2peak), lipid profile, fasting blood glucose (FBG), glycated hemoglobin (HbA1c), insulin resistance index (HOMA-IR), platelet miRNA-223 and P2RY12 expression were measured before and after the period.

RESULTS

There was a significant improvement in body weight, BMI, VO2peak, FBG, HbA1c, and HOMA-IR, after 12 weeks of AET (P <  0.01). Platelet aggregation decreased significantly after 12 weeks in the AET group compared with the CON (P <  0.001) group. Platelets' miRNA-223 and P2RY12 were significantly up- and down-regulated after AET in comparison with the CON group (P <  0.05), respectively. Moreover, the relative expression of miRNA-223 and P2RY12 significantly correlated with FBG changes following the intervention.

CONCLUSIONS

It can be concluded that long-term moderate-intensity aerobic training might be effective for reducing the occurrence of atherothrombotic events leading to premature death in T2DM patients through the modulation of miRNA-223, P2RY12 receptor expression, and platelet function.

Purinergic interplay between erythrocytes and platelets in diabetes-associated vascular dysfunction

Cardiovascular complications in diabetes are the leading causes for high morbidity and mortality. It has been shown that alteration of purinergic signaling contributes to diabetes-associated cardiovascular complications. Red blood cells (RBCs) and platelets play a fundamental role in regulation of oxygen transport and hemostasis, respectively. Of note, these cells undergo purinergic dysfunction in diabetes. Recent studies have established a novel function of RBCs as disease mediators for the development of endothelial dysfunction in type 2 diabetes (T2D). RBC-released ATP is defective in T2D, which has implication for induction of vascular dysfunction by dysregulating purinergic signaling. Platelets are hyperactive in diabetes. ADP-mediated P2Y₁ and P2Y₁₂ receptor activation contributes to platelet aggregation and targeting P2Y receptors particularly P2Y₁₂ receptor in platelets is effective for the treatment of cardiovascular events. In contrast to other P2Y₁₂ receptor antagonists, platelet-targeting drug ticagrelor has potential to initiate purinergic signaling in RBCs for the beneficial cardiovascular outcomes. It is increasingly clear that altered vascular purinergic signaling mediated by various nucleotides and nucleoside contributes to diabetes-associated vascular dysfunction. However, the contribution of complex purinergic networks between RBCs and platelets to the vascular dysfunction in diabetes remains unclear. This study discusses the possible interplay of RBCs and platelets via the purinergic network for diabetes-associated vascular dysfunction.

Inflammation in Metabolic and Cardiovascular Disorders-Role of Oxidative Stress

Cardiovascular diseases (CVD) constitute the main cause of death worldwide. Both inflammation and oxidative stress have been reported to be involved in the progress of CVD. It is well known that generation of oxidative stress during the course of CVD is involved in tissue damage and inflammation, causing deleterious effects such as hypertension, dysfunctional metabolism, endothelial dysfunction, stroke, and myocardial infarction. Remarkably, natural antioxidant strategies have been increasingly discovered and are subject to current scientific investigations. Here, we addressed the activation of immune cells in the context of ROS production, as well as how their interaction with other cellular players and further (immune) mediators contribute to metabolic and cardiovascular disorders. We also highlight how a dysregulated complement system contributes to immune imbalance and tissue damage in the context of increases oxidative stress. Additionally, modulation of hypothalamic oxidative stress is discussed, which may offer novel treatment strategies for type-2 diabetes and obesity. Together, we provide new perspectives on therapy strategies for CVD caused by oxidative stress, with a focus on oxidative stress.

Hematological parameters of type 2 diabetic adult patients at Debre Berhan Referral Hospital, Northeast Ethiopia: A comparative cross-sectional study

BACKGROUND

Diabetes is a global public health problem and associated with metabolic, cellular, and blood disturbances. Hematological changes have been reported in diabetes and play a major role in diabetes-associated complications. However, reports are contradicting and data on hematological parameters of type 2 diabetic patients in the study area are scarce. Therefore, the aim of this study was to assess the hematological parameters of type 2 diabetic adult patients at Debre Berhan Referral Hospital, Northeast Ethiopia from May 01 to June 30, 2020.

METHODS

A comparative cross-sectional study was conducted on 268 (134 type 2 diabetic patients and 134 controls) study participants selected by systematic random sampling technique. Socio-demographic, behavioral, and clinical data were collected using a structured questionnaire and checklist. Ethical approval was obtained from Jimma University. All phase of quality assurance was maintained. Hematological parameters and blood glucose levels were determined using UniCel DxH 800 (Beckman Coulter, USA) and Biosystems A25 (Costa Brava, Spain) analyzers, respectively. Independent t-test, Mann-Whitney U-test, correlation, and logistic regression were used during data analysis. P-value <0.05 was considered as statistically significant.

RESULTS

The current study found that total white blood cell count, absolute counts of neutrophil, lymphocyte, eosinophil, and basophil, red blood cell distribution width, platelet count, and mean platelet volume were significantly higher in type 2 diabetic patients as compared to the control group (P<0.05). On the other hand, the mean hemoglobin was significantly lower in type 2 diabetic patients than the control group (P = 0.007). Anemia was found in 17.9% of type 2 diabetic patients. Longer duration of diabetes (AOR = 3.05, 95% CI = 1.12-8.34) and milk consumption (AOR = 4.60, 95% CI = 1.50-14.00) were significantly associated with anemia.

CONCLUSION

This study showed a statistically significant variation in some hematological parameters of type 2 diabetic patients compared to control group. Anemia among type 2 diabetic patients was found to be a mild public health problem. Therefore, routine screening of hematological parameters should be considered for proper management of type 2 diabetic patients. Close attention should also be given to the duration of diabetes and dietary practice.

White blood cells and platelet profiles of diabetic patients at University of Gondar specialized referral hospital: A comparative cross-sectional study

BACKGROUND

Altered level of many hematological parameters such as white blood cells (WBC) and platelet function has been observed in diabetes mellitus (DM) patients. Therefore, this study aimed to determine the WBC and platelet profiles and their association with anthropometric measurement and blood pressure in DM patients and healthy controls.

METHOD

A comparative cross-sectional study was conducted on a total of 246 participants at the University of Gondar Specialized Referral Hospital. Venous blood with K₂ EDTA anticoagulant was drawn and analyzed by using Sysmex KX21N hematology analyzers for WBC and platelet parameters. Data were analyzed using Statistical Package for Social Sciences (SPSS) version 20. Results were presented as frequency and mean ± standard deviation (SD). The independent sample t test was used to compare quantitative variables between DM and control groups. The bivariate (spearman's rank) correlation was used to analyze continuous variables. A p-value ˂ 0.05 was considered as statistically significant.

RESULTS

The mean platelet count was significantly higher among diabetics (252.77 ± 77.7) compared to non-diabetic controls (208.22 ± 68), p < 0.001. Similarly, the total WBC count was higher among DM patients (6.95 ± 2.23) than in the controls (6.15 ± 1.95), p = 0.04. A significant negative correlation was also found between neutrophil and duration of illness in DM patients. Besides, there is a significant positive correlation between WBC and lymphocyte number with systolic blood pressure (SBP) in DM patients.

CONCLUSION

Platelet and WBC count were significantly higher in DM patients than in the controls. Therefore, routine screening and profile checking of those abnormal indices is recommended to minimize DM-related complications.

Association between insulin resistance and aspirin or clopidogrel resistance in Chinese patients with recent ischemic stroke/TIA

Objective: This study aims to discover whether insulin resistance is an independent predictor for antiplatelet drug resistance in patients with ischemic cerebrovascular disease.Methods: This study used a prospective cohort method. Patients diagnosed as minor ischemic stroke or transient ischemic attack (TIA) were enrolled successively. All patients have been administrated aspirin and/or clopidogrel and were tested for fasting glucose and insulin and platelet aggregation inhibition tests which was detected by light transmission aggregometry (LTA). The maximum platelet aggregation rate (AA) of ≥20% or the maximum platelet aggregation rate (ADP) of ≥50% was defined as antiplatelet drug resistance. Multivariable logistic regression was performed to estimate the association between HOMA-IR and antiplatelet drug resistance.Results: This study recruited successively 237 patients with mild-to-moderate ischemic stroke or TIA in Beijing Tiantan Hospital from 2018 to 2019. Of them 60 cases were recognized as having insulin resistance. There are 46 patients in insulin resistance group (76.7%) developed antiplatelet drug resistance, which was significantly more frequent than patients without insulin resistance (35%, P < 0.0001). Insulin resistance was an independent risk factor for antiplatelet drug resistance in patients with recent ischemic stroke/TIA after adjusted for confounding factors (Odds Ratio 5.281; 95%CI, 2.15 to 13.01, P < 0.0001).Conclusions: Insulin resistance was an independent predictor for development of antiplatelet drug resistance in patients with recent minor ischemic stroke or TIA. More attention should be paid to recognize these patients and antithrombotic effect should be monitored when antiplatelet drugs were applied to these patients.

Assessment of hematologic indices and their correlation to hemoglobin A1c among Bosnian children with type 1 diabetes mellitus and their healthy peers

Background

Altered levels of many hematological parameters have been directly associated with diabetes in adults, while studies on children with type 1 diabetes mellitus are lacking. The aim of this study was to determine hematological indices in diabetic Bosnian children in comparison to healthy controls as well as to correlate their levels to blood glucose and hemoglobin A1c.

Methods

100 healthy and 100 children with type 1 diabetes mellitus (age 1-18) were included in this study. Complete blood count, hemoglobin A1c, and glucose were tested. Results were analysed by IBM SPSS Statistics version 23.

Results

Significant differences (p<0.05) between healthy and diabetic children were found in relation to HbA1c, glucose, mean platelet volume, the number of white blood cells and erythrocytes, hematocrit, hemoglobin and MCH values. No gender differences or significant age differences were seen for hemoglobin, hematocrit, and MCV, while platelets, MPV, and MCH differed by age only in healthy children. When diabetic children were classified according to HbA1c levels, significant differences were seen for erythrocyte count and hematocrit value (p=0.013 and 0.019, respectively). The number of erythrocytes and white blood cells correlated significantly with HbA1c (p=0.037 and 0.027, respectively).

Conclusions

Lower levels of erythrocytes, hematocrit, and hemoglobin in diabetic compared to healthy children indicate possible development of anemia, while higher MCV, MCH, and MPV values indicate an alteration in erythrocyte morphology. Hematological indices could be a useful inexpensive tool in the diagnosis and follow up of type 1 diabetes in children.

Platelet Indices and Its Association with Microvascular Complications Among Type 2 Diabetes Mellitus Patients in Northeast Ethiopia: A Cross-Sectional Study

PURPOSE

Platelet indices have been shown to be associated with complications of diabetes mellitus (DM). However, the clinical relevance of platelet indices for assessing the risk of being microvascular complications among patients with DM is largely overlooked. Hence this study aimed to determine the association of platelet indices with microvascular complications among type 2 DM patients.

PATIENTS AND METHODS

A hospital-based cross-sectional study was conducted among 352 type 2 DM patients from April 1 to May 30/2019 at Debre Berhan Referral Hospital. Data were collected by interview, physical measurements, document review, and laboratory tests. Then the data were entered into Epi-data manager-4.4.1.0 and exported into SPSS-25 for analysis. Platelet indices were compared between participants with and without microvascular complications using an independent t-test. A logistic regression model was used to assess the association between microvascular complications and platelet indices. All inferences were considered statistically significant at P<0.05.

RESULTS

One hundred seventeen (33.2%) of participants were suffering from at least one microvascular complications. The mean platelet volume (MPV), platelet distribution width (PDW), and platelet-large cell ratio (P-LCR) were significantly increased in DM patients with complications as compared to without complications (13.57±2.17fl vs. 11.76±1.93fl), (16.57±2.49fl vs. 14.97±2.41fl) and (28.09±7.58% vs. 24.19±6.46%), respectively (all are P˂0.001). In multivariate logistic regression analysis, MPV (AOR=1.68, 95% CI: 1.37-2.05), PDW (AOR=1.37, 95% CI: 1.15-1.63), P-LCR (AOR=1.07, 95% CI: 1.01-1.14), age (AOR=1.07, 95% CI: 1.01-1.12), and duration of DM (AOR=1.31, 95% CI: 1.18-1.46) were significantly associated with the presence of microvascular complications.

CONCLUSION

MPV, PDW, and P-LCR were significantly higher among type 2 DM patients with microvascular complications. This indicates that platelet indices can be used as prognostic markers of vascular complications and can be used as simple and cost-effective parameters to predict microvascular complications particularly in patients with old age and long duration of DM.

Mean Platelet Volume and Platelet Distribution Width Correlate with Microvascular Complications in Egyptian People with Type 2 Diabetes Mellitus

BACKGROUND

Type 2 diabetes is a part of metabolic syndrome associated with a higher risk of vascular complications. Diabetes is characterized by changes in platelet morphology, function, and platelet hyperactivity so, it's considered a prothrombotic condition. Morbidity and mortality in people with type 2 diabetes-related to micro and macrovascular complications. Novel biomarkers are needed to identify and treat people at higher risk.

OBJECTIVE

The main objective of this controlled cross-sectional study was to evaluate Platelet volume indices (PVI) in subjects with type 2 diabetes with and without complications in comparison to subjects without diabetes.

METHODS

Hundred and thirty-five subjects aged from 35 to 60 years were subdivided into 3 groups. Group A includes 55 subjects with type 2 diabetes with complications. Group B includes 45 subjects with type 2 diabetes without complications. Group C includes 35 normal healthy subjects. Detailed clinical history was taken. Also, PVI, fasting blood glucose (FBG), hemoglobin A1c, and creatinine were obtained.

RESULTS

Mean Platelet Volume (MPV), Platelet Distribution Width (PDW), Plateletcrit (PCT), and Platelet large cell ratio (P-LCR) were significantly higher among subjects with retinopathy, nephropathy, and neuropathy than other subjects with diabetes who didn't develop complications (P<0.001). At cutoff value > 11.9 fL, MPV have diagnostic sensitivity 80% and specificity 97.8%. Whereas PDW >16.9fL has a sensitivity of 74.5% and specificity of 100% for diabetic microvascular complications (retinopathy, nephropathy, and neuropathy).

CONCLUSION

MPV and PDW may be considered as possible biomarkers for the early detection of diabetic microvascular complications.

Multiple autoimmune syndrome complicating the management of diabetic retinopathy

Purpose

Observations

Conclusion and Importance

Effect of prediabetes on asprin or clopidogrel resistance in patients with recent ischemic stroke/TIA

OBJECTIVE

Diabetes mellitus (DM) had been discovered as an independent risk factor for high on-treatment platelet reactivity (HPR) in patients with ischemic stroke. However, studies on the relationship between prediabetes and the occurrence of HPR remain scarce. This study is aimed at clarifying the association between prediabetes and HPR among patients with recent ischemic stroke or transient ischemic stroke (TIA).

METHODS

Patients with ischemic stroke or TIA within 90 days after onset were recruited consecutively. All patients were divided into three groups: DM, prediabetes, and normal glucose tolerance according to fasting glucose, HbA1c, or OGTT. Three months later, all patients were performed platelet aggregation inhibition test and screened for high on-treatment platelet reactivity. The effect of prediabetes on HPR was analyzed in a multivariable logistic regression model.

RESULTS

This study recruited 237 patients with ischemic stroke or TIA, including 57 cases with prediabetes, 108 with DM, and 72 with normal glucose tolerance. Aspirin and/or clopidogrel resistance was discovered in 28 cases among prediabetes group, which was significantly more frequent than normal glucose tolerance group(49.1% versus 33.3%, P = 0.046). After adjusting for confounding factors, prediabetes was found as an independent risk factor for high on-treatment platelet reactivity (HPR) among patients with recent ischemic stroke or TIA (odds ratio 2.92; 95% CI, 1.29 to 6.63, P = 0.01).

CONCLUSIONS

Prediabetes was an independent risk factor for high on-treatment platelet reactivity in patients with recent ischemic cerebrovascular disease. Patients with prediabetes should be highlighted for the efficacy test of antiplatelet drugs.

Family history of diabetes is associated with diabetic foot complications in type 2 diabetes

To investigate the relationship between diabetic foot complications (DFCs) and clinical characteristics, especially the number and types of first-degree family members with diabetes. A total of 8909 type 2 diabetes patients were enrolled. The clinical characteristics of these patients, including DFCs and family history of diabetes (FHD), were collected from medical records. Multiple regression was used to investigate the association between FHD and DFCs after adjusting for confounding factors. The patients with one and more than one first-degree family member with diabetes accounted for 18.7% and 12.8%, respectively. The proportions of the participants with a father with diabetes, a mother with diabetes, both parents with diabetes, siblings with diabetes, father and siblings with diabetes, mother and siblings with diabetes, and both parents and siblings with diabetes were 3.5%, 6.2%, 1.1%, 14.4%, 1.5%, 4%, and 0.7%, respectively. The multiple regression analysis showed that the number of family members with diabetes was positively associated with DFCs. However, among the different types of FHD, only the patients with a mother with diabetes showed a statistical association with DFCs. In addition to FHD, other factors, including gender, body mass index, platelet count, hemoglobin levels, albumin levels, high-density cholesterol levels, diabetic peripheral neuropathy, and the use of lipid-lowering agents, oral hypoglycemic agents, and insulin, were also associated with DFCs. DFCs were associated with different numbers of family members with diabetes and types of FHD. This association reveals the importance of genetic and environmental factors in DFCs and highlights the importance of adding FHD to public health strategies targeting detecting and preventing the disease.

Increased Intraplatelet ADMA Level May Promote Platelet Activation in Diabetes Mellitus

Background

Antiplatelet therapy has become a standard therapeutic approach in the secondary prevention of cardiovascular system disorders of thrombotic origin. Patients with concomitant diabetes mellitus (DM) obtain fewer benefits from this treatment. Hence, the pathophysiology of altered platelet function in response to glucose metabolism impairment should be of particular interest.

Objectives

The aim of our study was to verify if the platelet expression of the asymmetric dimethylarginine (ADMA) in diabetic patients differs in comparison to the nondiabetic ones. The correlation of platelet-ADMA with platelet activation and aggregation as well as with other risk factors was also investigated. Material and Methods. A total of 61 subjects were enrolled in this study, including thirty-one type 2 diabetic subjects without diabetes-related organ damage. Physical examination was followed by blood collection with an assessment of platelet aggregation, traditional biochemical cardiovascular risk factors, and evaluation of nitric oxide bioavailability parameters in plasma and thrombocytes. Subsequently, the assessment of endothelial function using Peripheral Arterial Tonometry and Laser Doppler Flowmetry (LDF) was performed.

Results

In the DM group, elevated concentration of intraplatelet ADMA and higher ADMA/SDMA ratio compared to the control group was observed. It was accompanied by higher ADP-mediated platelet aggregation and lower microvascular response to a local thermal stimulus measured by LDF in the diabetes group.

Conclusions

Type 2 diabetes is related to higher intraplatelet concentration of asymmetric dimethylarginine (ADMA), which may result in impaired platelet-derived nitric oxide synthesis and subsequent increased platelet activity, as assessed by the ADP-induced aggregation. Laser Doppler Flowmetry, compared to EndoPAT 2000, appears to be a more sensitive indicator of the impaired microvasculature vasodilation in diabetics without the presence of clinically significant target organ damage.

Anastomotic Revision in Head and Neck Free Flaps

OBJECTIVES/HYPOTHESIS

Predictors of free tissue transfer (FTT) failure and the need for postoperative revision (POR) have been extensively studied; however, there are little data evaluating outcomes when intraoperative revision (IOR) at initial surgery is required. This study seeks to better understand the impact IOR of the pedicle has on FTT outcomes.

STUDY DESIGN

Retrospective review of 2482 consecutive patients across three tertiary institutions.

METHODS

Adult patients (>18) who received a FTT and underwent anastomotic revision from 2006 to 2019 were included. Logistic regression was performed to predict revision, and recursive partitioning was performed to classify risk of failure based on type of revision and vessels revised.

RESULTS

Failure rates for IOR (19%) and POR (27%) were higher compared to a nonrevised failure rate of 2% (P < .01 and P < .01, respectively). Intraoperative venous revision (IORv, n = 13), arterial (IORa, n = 114), and both (IORb, n = 11) were associated with failure rates of 8% (odds ratio [OR] 3.5, P = .23), 18% (OR = 9.0, P < .01), 45% (OR = 35.3, P = <.01), respectively. Arterial revision was most common among IOR (83%, P < .01). Postoperative venous revision (PORv, n = 35), arterial (PORa, n = 36), and both (PORb, n = 11) were associated with failure rates of 20% (OR = 15.7, P < .01), 27% (OR = 10.6, P < .01), and 39% (OR = 27.0, P < .01), respectively. Failure rate for flaps that had POR after IOR (PORi, n = 11) was 45% (OR = 18.2, P < .01). Diabetes predicted IOR (P = .006); tobacco use, heavy alcohol use, and prior radiation predicted POR (P = .01, P = .05, and P = .01, respectively).

CONCLUSION

Both IOR and POR were associated with increased failure compared to nonrevised flaps. The risk of failure increases sequentially with intraoperative or POR of the vein, artery, or both vessels. Revision of both vessels and POR after IOR are strongly predictive of failure.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:1035-1041, 2021.

The Impact of Coexistence of Smoking and Diabetes on the Coronary Artery Severity and Outcomes following Percutaneous Coronary Intervention: Results from the 1ST Jordanian PCI Registry

Introduction

Diabetes mellitus (DM) and smoking are highly prevalent among Middle Eastern patients admitted with acute coronary syndrome (ACS) or who undergo percutaneous coronary intervention (PCI).

Methods

This study used the analysis of the data from the first Jordanian PCI registry (JoPCR1) to determine the impact of coexistence of smoking and diabetes mellitus on the coronary artery severity and outcome following percutaneous coronary intervention in Middle Eastern patients.

Results

Of 2426 patients enrolled, 1300 (53.6%) and 1055 (43.5%) were diabetics and smokers, respectively. The patients' age was 59.0 ± 10.1 and ranged between 24 and 95 years. Males comprised 79.4% of all patients. The patients were divided into four groups: nondiabetic-nonsmokers (22.2%), diabetic-nonsmokers (34.3%), nondiabetic-smokers (24.2%), and diabetic-smokers (19.2%). Compared with the other three groups, patients in the diabetic-nonsmoker group were older, more likely to be females, and having a higher prevalence of hypertension, dyslipidemia, chronic renal disease, and history of CVD and revascularization. Consequently, the diabetic-nonsmoker patients (but not the diabetic-smokers) had a higher prevalence of multivessel CAD and PCI than the other three groups, highlighting the importance of other risk factors (age, gender, metabolic syndrome, and comorbidities) and not only smoking in predisposing for CAD. Furthermore, those patients had a higher incidence of ACS as an indication for PCI than the stable coronary disease (73% vs 27%) and the highest CRUSADE bleeding risk score (63.9%) among other groups. The in-hospital events including in-stent thrombosis and emergency CABG events did not significantly differ among groups (p = 0.5 and 0.22). Heart failure and major bleeding events occurred significantly higher among diabetic-nonsmokers compared to other groups. In-hospital deaths occurred significantly more among diabetic-nonsmokers. Moreover, the one-month and one-year follow-up outcome events (the mortality rate, in-stent thrombosis, readmission for ACS, coronary revascularization, and major bleedings) occurred more frequently in the diabetic-nonsmoker group. However, the difference was statistically significant only for major bleeding incidences.

Conclusions

In this analysis of a completed prospective Middle Eastern PCI registry, the majority of the diabetic-nonsmoker (and not the diabetic-smokers) patients (73%) presented with ACS. This group was the highest at risk for in-hospital PCI complications as well as the worst in outcomes after one year of follow-up. Those patients were more likely to be older, female, and have the worst cardiovascular baseline features, highlighting the importance of other risk factors (age, gender, metabolic syndrome, and comorbidities) and not only smoking in predisposing for CAD. Thus, more sufficient education about controlling CVD risk factors should be implemented in the Middle Eastern region.

Association between mean platelet volume in the pathogenesis of type 2 diabetes mellitus and diabetic macrovascular complications in Japanese patients

AIMS/INTRODUCTION

Mean platelet volume (MPV) is a widely used biological marker of platelet function and activity. Increased MPV is associated with accelerated thrombopoiesis and an elevated risk of cardiovascular disease. However, it is not known whether higher MPV is related to the pathogenesis of type 2 diabetes and diabetic macrovascular complications in Japanese patients. Therefore, we analyzed MPV and its correlation with atherosclerosis in Japanese patients with type 2 diabetes and those who had prediabetes.

MATERIALS AND METHODS

We divided the patients into three groups: normoglycemic patients (n = 56), prediabetes patients (n = 44) and type 2 diabetes patients group, (n = 115). We measured platelet parameters and evaluated arterial stiffness in the three groups.

RESULTS

Significantly higher MPV was found in the type 2 diabetes mellitus and prediabetes patients compared with normoglycemic patients. MPV was significantly correlated with fasting blood glucose and glycated hemoglobin levels. Multiple linear regression analysis showed that MPV was positively correlated with HbA1c, even after adjustment for confounding factors. In the evaluation of arterial stiffness by measuring the cardio-ankle vascular index and maximum intima-media thickness, MPV showed a positive correlation with these parameters.

CONCLUSIONS

These findings suggest that MPV was significantly increased in the early stage of type 2 diabetes. We showed positive correlations between MPV and HbA1c levels, and between MPV and arterial stiffness in Japanese patients with type 2 diabetes.

Palanisamy UD, Ahmad B, Abdul Kadir K. The Effects of Tocotrienol-Rich Vitamin E (Tocovid) on Diabetic Neuropathy: A Phase II Randomized Controlled Trial

Chronic hyperglycemia increases oxidative stress, activates inflammatory pathways and reduces nerve growth factor (NGF) among diabetic patients, which contribute to development of diabetic peripheral neuropathy (DPN). Tocotrienol-Rich Vitamin E (Tocovid) possesses potent antioxidant and anti-inflammatory properties which are postulated to target these pathogeneses in order to ameliorate DPN. This study aims to evaluate the effects of Tocovid on nerve conduction parameters and serum biomarkers among diabetic patients. This multicenter, prospective, randomized, double-blind, placebo-controlled clinical trial was conducted on 80 eligible participants. The intervention group (n = 39) was randomly allocated to receive 200 mg of Tocovid twice a day, and the control group (n = 41) received placebo twice a day. At the end of eight weeks, the nerve conduction parameters, as assessed by nerve conduction study, as well as serum biomarkers (NGF, malondialdehyde, vascular cell adhesion molecule 1, tumor necrosis factor receptor 1 and thromboxane B2) were compared between the two groups. Compared to placebo, Tocovid significantly improves the nerve conduction velocities of all nerves (+1.25 m/s, interquartile range [IQR] 3.35, p < 0.001, median nerve; +1.60 m/s, IQR 1.80, p < 0.001, sural nerve; +0.75 m/s, IQR 2.25, p < 0.001, tibial nerve). Meanwhile, the levels of serum NGF were significantly higher in the Tocovid group as compared to placebo at eight weeks post-intervention. Participants receiving Tocovid illustrated highly significant improvement in terms of nerve conduction velocities for all nerves tested after eight weeks of supplementation. In addition, Tocovid supplementation elevated the levels of serum NGF, in which its increase is postulated to reflect enhanced neuronal functions. This novel finding suggests that Tocovid could be a disease-modifying agent targeting serum NGF to improve nerve conduction velocities.

[E-Selectin as a Marker of Endothelial Dysfunction in Patients with Coronary Artery Disease Including Those with Type 2 Diabetes Mellitus]

Aim To determine concentration of the endothelial dysfunction (ED) marker, serum E-selectine, in patients with ischemic heart disease (IHD) in combination with type 2 diabetes mellitus (DM) and without DM.Material and methods The study included 60 IHD patients; 31 of them also had type 2 DM. E-selectin was measured in blood of all patients. In addition, a comprehensive evaluation of the morpho-functional condition of large blood vessels and microvasculature (MV) was performed by laser finger plethysmography (LFP) and nailfold computed videocapillaroscopy (CVC).Results Concentration of E-selectin was increased in IHD patients with type 2 DM (35.2 [29.0; 47.35] ng / ml vs. 31.7 [20.85; 36.68] ng / ml for IHD patients; p=0.028). A significant (p=0.018 and 0.016, respectively) decrease in the phase shift was observed in IHD patients with type 2 DM ( - 4.4 [ - 8.7; - 2.45] ms) compared to IHD patients ( - 1.9 [ - 3.95; - 0.38] ms). The capillary density evaluated in the venous occlusion test was reduced in IHD patients with type 2 DM (67.70 [57.83; 80.69]) compared to IHD patients (80.80 [69.05; 99.08]).Conclusion The signs of ED observed in patients of both groups were more pronounced in IHD patients with type 2 DM.

β-Amyloid and mitochondrial-derived peptide-c are additive predictors of adverse outcome to high-on-treatment platelet reactivity in type 2 diabetics with revascularized coronary artery disease

BACKGROUND AND AIMS

Increased β-amyloid and decreased mitochondrial-derived peptide (MOTS-c), are reported in diabetes. We investigated their additive value to high on-clopidogrel platelet reactivity (HPR) for adverse outcome in type 2 diabetics after recent revascularization.

PATIENTS AND METHODS

In 121 type II diabetics, treated with clopidogrel and aspirin, (93 males, mean age 67.2 years) we measured: (a) maximum platelet aggregation to adenosine diphosphate (ADP) by light transmission aggregometry (LTAmax), (b) malondialdehyde (MDA), as oxidative stress marker, (c) MOTS-c, (d) β-amyloid blood levels. Cardiac death and acute coronary syndromes (MACE) were recorded during 2 years of follow-up.

RESULTS

Out of 121 patients, 32 showed HPR (LTAmax > 48%,). At baseline, HPR was associated with β-amyloid > 51 pg/ml (p = 0.006) after adjusting clinical variables, HbA1c, MOTS-c, MDA and medication. During follow-up, 22 patients suffered a MACE. HPR, β-amyloid > 51 pg/ml and MOTS-c < 167 ng/ml were predictors of MACE (relative risk 3.1, 3.5 and 3.8 respectively, p < 0.05) after adjusting for confounders and medication. There was significant interaction between HPR and β-amyloid or MOTS-c for the prediction of MACE (p < 0.05). Patients with HPR and β-amyloid > 51 mg/dl or HPR and MOTS-c concentration < 167 ng/ml had a fourfold higher risk for MACE than patients without these predictors (relative risk 4.694 and 4.447 respectively p < 0.01). The above results were confirmed in an external validation cohort of 90 patients with diabetes and CAD.

CONCLUSIONS

Increased β-amyloid or low MOTS-c are additive predictors to high on-clopidogrel platelet reactivity for adverse outcome in diabetics with CAD during 2-years follow-up. Clinical Trial Registration-URL: https://www.clinicaltrials.gov. Unique identifier: NCT04027712.

Inhibition of pyruvate dehydrogenase complex activity by 3-bromopyruvate affects blood platelets responses in type 2 diabetes

BACKGROUND

Hyperactivation of blood platelets is an essential factor in the pathomechanism of diabetes-evoked angiopathies. The aim of this work was to investigate whether blood platelets hyperactivation resulting from type 2 diabetic hyperglycaemia-increased pyruvate dehydrogenase complex activity and excessive acetyl-CoA accumulation may be brought to the normal range by the enzyme inhibitors.

METHODS

Platelets were isolated from the blood of 9 type 2 diabetic patients and 10 healthy donors. Effects of 3-bromopyruvate and 3-nitropropionate on pyruvate dehydrogenase complex (PDHC) and succinate dehydrogenase activities, as well as levels of acetyl-CoA, ATP, thiobarbituric acid reactive species and aggregation were assessed in non-activated and thrombin-activated platelets.

RESULTS

In type 2 diabetic patients fasting plasma glucose and fructosamine levels were 61 and 64% higher, respectively, than in the healthy group (p < 0.001). In non-activated diabetic platelets PDHC activity, PDHC-E2, acetyl-CoA and ATP levels were 66, 70, 68 and 60%, higher, respectively, than in platelets from healthy controls (p < 0.01). 3-bromopyruvate (0.1 mM) decreased pyruvate dehydrogenase activity in healthy and diabetic platelets by 42% and 59%, respectively. Similar inhibitory effects were observed for acetyl-CoA and ATP levels, aggregation and TBARS accumulation rates. Succinate dehydrogenase activity was inhibited by 3-nitropropionate (10 mM) to 38 and 41% of control values in healthy and diabetic platelets, respectively, but affected neither function nor acetyl-CoA metabolism in platelets of both groups.

CONCLUSIONS

These data indicate that inhibition of pyruvate dehydrogenase excessive activity in diabetic platelets by 3-bromopyruvate may normalise their functional parameters through adjustment of acetyl-CoA/ATP levels to control values. Platelets from blood of diabetic patients display higher activities of pyruvate dehydrogenase complex (PDHC), higher levels of dihydrolipoate transacetylase (DLAT, E2 subunit of PDHC) as well as higher levels of acetyl-CoA yielding greater ATP/ADP accumulation than in platelets of normoglycemic subjects. Therefore, in diabetic platelets, thrombin caused higher release of ATP/ADP triggering excessive production of reactive oxygen species (ROS) and stronger aggregation compared to control platelets. In diabetic platelets, relative excess of DLAT in PDHC made them highly susceptible to 3-bromopyruvate (3BrP) inhibition. Resulting limitation of acetyl-CoA provision by 3-BrP normalised activity of diabetic platelets.