Comparative Determination of Mitochondrial Biomarkers and Their Relationship With Insulin Resistance in Type 2 Diabetic Patients: An Observational Cross‐Sectional Study

ABSTRACT Introduction Data suggest malfunctioning mitochondria reduce oxidation and adenosine triphosphate (ATP) production, disrupting insulin signalling. Cytochrome c (CC), acylcarnitine (AC) and citrate synthase (CS) are essential components of the mitochondria machinery and can be used as reliable biomarkers of mitochondrial dysfunction. This study aimed to determine whether mitochondrial biomarkers (AC, CS and CC) are altered in individuals with type 2 diabetes mellitus (T2DM) and to examine the association between these biomarkers and insulin resistance. Methodology A cross‐sectional observational study that recruited 170 participants (88 with T2DM and 82 without DM) was conducted. Blood samples were collected from the recruits and analysed for levels of fasting glucose (FBG), AC, CS, CC, insulin, total cholesterol, triglycerides (TG), glycated haemoglobin (HbA1c) and magnesium. Blood pressure (BP) and anthropometric characteristics of participants were also taken. Appropriate formulas were used to determine %body fat, body mass index (BMI), waist‐to‐hip ratio (WHR), the homeostatic model assessment for insulin resistance (HOMA‐IR) and insulin sensitivity (HOMA‐β). Results Patients with T2DM had higher levels of CC, %body fat, FBG, TG, HbA1c, BMI and HOMA‐IR than controls (p < 0.05, respectively). Results showed a significant relationship between circulating CC levels versus HOMA‐β (r = −0.40, p = 0.001), CS (r = −0.70, p = 0.001) and AC (r = −0.72, p = 0.001) levels in patients with T2DM. The adjusted odds increased in the T2DM patients for VLDL (OR = 6.66, p = 0.002), HbA1c (OR = 6.50, p = 0.001), FPG (OR = 3.17, p = 0.001), TG (OR = 2.36, p = 0.010), being female (OR = 2.09, p = 0.020) and CC (OR = 1.14, p = 0.016). Conclusion Overall, alterations in mitochondrial biomarkers, measured by AC, CC and CS, were observed in people with T2DM and showed a direct relationship with insulin resistance. These findings are potentially significant in Africa, although additional confirmation from a larger cohort is necessary

Effect of circulating ceramides on adiposity and insulin resistance in patients with type 2 diabetes: An observational cross‐sectional study

Abstract Introduction Insulin resistance (IR) is one of the common chronic metabolic disorders in Africa and elsewhere. Accumulation of lipids in the body may be due to an imbalance in the metabolism of lipids, glucose and proteins. Ceramides are a sphingolipid class of lipids that are biologically active and vital in the production of more complex lipids. Circulating ceramides are thought to have a role in the development of obesity‐related IR, although the precise involvement remains unclear. Aim To investigate the impact of circulating ceramide on IR and body adiposity in people with and without type 2 diabetes mellitus (T2DM). Methodology The study was observational and cross‐sectional. There were a total of 84 volunteers with T2DM and 75 nondiabetics (control). The participants' ages, body mass indexes (BMI), waist circumferences, and blood pressure (BP) were among the clinical parameters assessed. Ceramide levels, fasting plasma glucose (FPG), lipids, basal insulin levels and glycated haemoglobin (HbA1c) were also measured. Additionally, the homeostatic model assessment for IR (HOMA‐IR) and beta cell function (HOMA‐β) were computed. Results T2DM and control participants had different mean values for anthropometric parameters, BP, FPG, HbA1c, lipids, insulin, HOMA‐IR, HOMA‐β and ceramide levels (p < .05 for all). HOMA‐IR, HOMA‐β and cardiovascular risk were significant correlates with ceramide levels in the T2DM group (r = 0.24; −0.34; 0.24, p < .05, respectively). Further, FPG (OR = 1.83, p = .01) and ceramide (OR = 1.05, p = .01) levels were significant predictors of IR in the case group. Conclusion Patients with T2DM exhibited high ceramide concentrations, which, when combined with high FPG, were associated with IR. The consequences of circulating ceramides in health and disease; however, merit further research

Blood C‐peptide concentration as a proxy marker of cardiovascular disease: An observational cross‐sectional study

Abstract Background and Aims Cardiovascular diseases (CVDs) are among the leading causes of disability and early death in sub‐Saharan Africa. Most of the current blood tests for CVD diagnosis involve performing about three test profiles; often at additional cost to patients. C‐peptide, a cleavage product of proinsulin, is a promising marker that has the potential to serve as a proxy marker for diagnosing CVDs in resource‐poor settings. Methodology The study was an observational cross‐sectional one and involved 127 consenting persons diagnosed with CVD and 127 individuals without CVD. The socio‐demographic and clinical characteristics of participants were obtained. Blood levels of C‐peptide, fasting plasma glucose (FPG), total creatinine kinase (CK), creatine kinase myocardial bound (CKMB), lactate dehydrogenase (LDH), propeptide of brain natriuretic peptide (PBNP), Troponin T, lipids, and biomarkers of kidney and liver function were analyzed using ELISA and an automated analyzer. Insulin resistance was computed using the modified homeostatic model assessment (HOMA‐IR). Results The CVD Group had significantly higher levels of C‐peptide, CK, CKMB, troponin T, PBNP, FPG, HOMA‐IR, and several selected kidney, liver, and lipid parameters compared to the non‐CVD Group (p < 0.05 for all). Troponin T recorded a positive correlation (r = 0.34, p < 0.001) with C‐peptide among the CVD Group. The sensitivity and specificity of C‐peptide in identifying CVD were 96.1% and 91.3% respectively (area under the curve = 0.938, p < 0.001). Conclusion C‐peptide levels were higher in the CVD Group and appeared to be a valuable (high sensitivity and specificity) biomarker in detecting CVD