Link between Metabolic Syndrome and Insulin Resistance

Metabolic syndrome (MetS) is a leading public health and clinical challenge worldwide. MetS represents a group of interrelated risk factors that predict cardiovascular diseases (CVD) and diabetes mellitus (DM). Its prevalence ranges between 10 and 84%, depending on the geographic region, urban or rural environment, individual demographic characteristics of the population studied (sex, age, racial and ethnic origin), as well as the criteria used to define MetS. Persons with MetS have higher mortality rate when compared with people without MetS, primarily caused by progressive atherosclerosis, accelerated by pro-inflammatory and pro-coagulation components of MetS. Considering the high prevalence of metabolic disorders (glucose metabolism disorder, hypertension, dyslipidaemia, obesity etc.), preventive healthcare should focus on changing lifestyle in order to reduce obesity and increase physical activity. This narrative review considers the available evidence from clinical and experimental studies dealing with MetS, and current treatment options for patients with insulin resistance and MetS.

Effects of N-3 PUFAs supplementation on insulin resistance and inflammatory biomarkers in hemodialysis patients

AIMS/HYPOTHESIS

It was suggested that polyunsaturated n-3 fatty acids (n-3 PUFAs) could improve insulin sensitivity and have an anti-inflammatory effects in overall population. This study investigates a possible effect of n-3 PUFAs supplementation on the insulin sensitivity and some inflammatory markers; hence, patients with chronic renal failure (CRF) on maintenance hemodialysis (MHD) are presented with insulin resistance.

METHODS

This study explored the ratio between red blood cells (RBC) phospholipid long chain fatty acids (LC FAs) and components of metabolic syndrome (MeS) in 35 patients (mean age 54.50 +/- 11.99 years) with CRF on MHD. Furthermore, the effects of omega-3 FA eight-week's supplementation (EPA+DHA, 2.4 g/d) on the MeS features and inflammatory markers TNF-alpha, IL 6, and hsCRP were examined.

RESULTS

Supplementation increased EPA and DHA levels in RBCs (p = 0.009 for EPA and p = 0.002 for DHA). Total n-6 PUFAs: n-3 PUFAs ratio tended to be lower after supplementation (p = 0.31), but not significantly. Data revealed a significant decrease of saturated FAs (SFA) (p = 0.01) as well as total SFA: n-3 PUFAs ratio during the treatment (p = 0.04). The values of serum insulin and calculated IR index-IR HOMA were reduced after supplementation (p = 0.001 for both). There was a significant decrease in the levels of all inflammatory markers (p = 0.01 for TNF alpha, p = 0.001 for IL 6, p = 0.001 for hsCRP, and p = 0.01 for ferritin). In multivariate regression analysis, only the changes in n-6 PUFAs: n-3 PUFAs ratio independently contributed to 40% of the variance in IR HOMA. The impact of changes in PUFAs level in RBCs membrane phospholipid fatty acids on inflammation markers was also registered. The changes in n-6: n-3 PUFAs ratio independently contributed to 18% of the variance in TNF alpha.

CONCLUSION

It was concluded that the EPA and DHA moderate dose administration in the patients with CRF on MHD had a beneficial effect on insulin resistance decrease. The anti-inflammatory effects of the supplemented PUFAs were also presented.

Atherosclerosis Linked to Aberrant Amino Acid Metabolism and Immunosuppressive Amino Acid Catabolizing Enzymes

Cardiovascular disease is the leading global health concern and responsible for more deaths worldwide than any other type of disorder. Atherosclerosis is a chronic inflammatory disease in the arterial wall, which underpins several types of cardiovascular disease. It has emerged that a strong relationship exists between alterations in amino acid (AA) metabolism and the development of atherosclerosis. Recent studies have reported positive correlations between levels of branched-chain amino acids (BCAAs) such as leucine, valine, and isoleucine in plasma and the occurrence of metabolic disturbances. Elevated serum levels of BCAAs indicate a high cardiometabolic risk. Thus, BCAAs may also impact atherosclerosis prevention and offer a novel therapeutic strategy for specific individuals at risk of coronary events. The metabolism of AAs, such as L-arginine, homoarginine, and L-tryptophan, is recognized as a critical regulator of vascular homeostasis. Dietary intake of homoarginine, taurine, and glycine can improve atherosclerosis by endothelium remodeling. Available data also suggest that the regulation of AA metabolism by indoleamine 2,3-dioxygenase (IDO) and arginases 1 and 2 are mediated through various immunological signals and that immunosuppressive AA metabolizing enzymes are promising therapeutic targets against atherosclerosis. Further clinical studies and basic studies that make use of animal models are required. Here we review recent data examining links between AA metabolism and the development of atherosclerosis.

Role of C-Reactive Protein in Diabetic Inflammation

Even though type 2 diabetes mellitus (T2DM) represents a worldwide chronic health issue that affects about 462 million people, specific underlying determinants of insulin resistance (IR) and impaired insulin secretion are still unknown. There is growing evidence that chronic subclinical inflammation is a triggering factor in the origin of T2DM. Increased C-reactive protein (CRP) levels have been linked to excess body weight since adipocytes produce tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6), which are pivotal factors for CRP stimulation. Furthermore, it is known that hepatocytes produce relatively low rates of CRP in physiological conditions compared to T2DM patients, in which elevated levels of inflammatory markers are reported, including CRP. CRP also participates in endothelial dysfunction, the production of vasodilators, and vascular remodeling, and increased CRP level is closely associated with vascular system pathology and metabolic syndrome. In addition, insulin-based therapies may alter CRP levels in T2DM. Therefore, determining and clarifying the underlying CRP mechanism of T2DM is imperative for novel preventive and diagnostic procedures. Overall, CRP is one of the possible targets for T2DM progression and understanding the connection between insulin and inflammation may be helpful in clinical treatment and prevention approaches.

New insights on the cardiovascular effects of IGF-1

INTRODUCTION

Cardiovascular (CV) disorders are steadily increasing, making them the world's most prevalent health issue. New research highlights the importance of insulin-like growth factor 1 (IGF-1) for maintaining CV health.

METHODS

We searched PubMed and MEDLINE for English and non-English articles with English abstracts published between 1957 (when the first report on IGF-1 identification was published) and 2022. The top search terms were: IGF-1, cardiovascular disease, IGF-1 receptors, IGF-1 and microRNAs, therapeutic interventions with IGF-1, IGF-1 and diabetes, IGF-1 and cardiovascular disease. The search retrieved original peer-reviewed articles, which were further analyzed, focusing on the role of IGF-1 in pathophysiological conditions. We specifically focused on including the most recent findings published in the past five years.

RESULTS

IGF-1, an anabolic growth factor, regulates cell division, proliferation, and survival. In addition to its well-known growth-promoting and metabolic effects, there is mounting evidence that IGF-1 plays a specialized role in the complex activities that underpin CV function. IGF-1 promotes cardiac development and improves cardiac output, stroke volume, contractility, and ejection fraction. Furthermore, IGF-1 mediates many growth hormones (GH) actions. IGF-1 stimulates contractility and tissue remodeling in humans to improve heart function after myocardial infarction. IGF-1 also improves the lipid profile, lowers insulin levels, increases insulin sensitivity, and promotes glucose metabolism. These findings point to the intriguing medicinal potential of IGF-1. Human studies associate low serum levels of free or total IGF-1 with an increased risk of CV and cerebrovascular illness. Extensive human trials are being conducted to investigate the therapeutic efficacy and outcomes of IGF-1-related therapy.

DISCUSSION

We anticipate the development of novel IGF-1-related therapy with minimal side effects. This review discusses recent findings on the role of IGF-1 in the cardiovascular (CVD) system, including both normal and pathological conditions. We also discuss progress in therapeutic interventions aimed at targeting the IGF axis and provide insights into the epigenetic regulation of IGF-1 mediated by microRNAs.

Tryptophan Metabolism in Atherosclerosis and Diabetes

The essential amino acid tryptophan (Trp) undergoes catabolism through several pathways, producing biologically active metabolites that significantly impact physiological processes. The metabolic pathway responsible for the majority of Trp catabolism is the kynurenine synthesis pathway (KP). Serotonin and melatonin are among the most essential Trp pathways degradation products. It has emerged that a strong relationship exists between alterations in Trp metabolism and the onset and progression of atherosclerosis and diabetes. Atherosclerosis is a chronic inflammatory disease of the small and medium arteries wall caused by maladaptive local immune responses, which underpins several cardiovascular diseases (CVD). Systemic low-grade immune-mediated inflammation is implicated in atherosclerosis where pro-inflammatory cytokines, such as interferon-γ (IFN-γ), play a significant role. IFN-γ upregulates the enzyme indoleamine 2,3-dioxygenase (IDO), decreasing serum levels of the Trp and increasing metabolite levels of kynurenine. Increased IDO expression and activity could accelerate the atherosclerosis process. Therefore, activated IDO inhibition could offer possible treatment options regarding atherosclerosis management. Diabetes is a chronic metabolic disease characterized by hyperglycemia that, over time, leads to severe damage to the heart, blood vessels, eyes, kidneys, and peripheral nerves. Trp serum levels and lower activity of IDO were higher in future type 2 diabetes (T2DM) patients. This article reviews recent findings on the link between mammalian Trp metabolism and its role in atherosclerosis and diabetes and outlines the intervention strategies.

Hypothyroidism and Risk of Cardiovascular Disease

Thyroid hormones (TH) have a significant impact on cellular oxidative metabolism. Besides that, they maintain vascular homeostasis by positive effects on endothelial and vascular smooth muscle cells. Subclinical (SCH) and clinical (CH) hypothyroidism influences target organs by changing their morphology and function and impaired blood and oxygen supply induced by accelerated atherosclerosis. The increased risk of acceleration and extension of atherosclerosis in patients with SCH and CH could be explained by dyslipidemia, diastolic hypertension, increased arterial stiffness, endothelial dysfunction, and altered blood coagulation. Instability of atherosclerotic plaque in hypothyroidism could cause excessive activity of the elements of innate immunity, which are characterized by the significant presence of macrophages in atherosclerotic plaques, increased nuclear factor kappa B (NFkB) expression, and elevated levels of tumor necrosis factor α (TNF-α) and matrix metalloproteinase (MMP) 9, with reduced interstitial collagen; all of them together creates inflammation milieu, resulting in plaque rupture. Optimal substitution by levothyroxine (LT4) restores biochemical euthyroidism. In postmenopausal women and elderly patients with hypothyroidism and associated vascular comorbidity, excessive LT4 substitution could lead to atrial rhythm disorders and osteoporosis. Therefore, it is of interest to maintain thyroid-stimulating hormone (TSH) levels in the reference range, thus eliminating the deleterious effects of lower or higher TSH levels on the cardiovascular system. This review summarizes the recent literature on subclinical and clinical hypothyroidism and atherosclerotic cardiovascular disease and discusses the effects of LT4 replacement therapy on restoring biochemical euthyroidism and atherosclerosis processes.

Insulin, thrombine, ERK1/2 kinase and vascular smooth muscle cells proliferation

Vascular smooth muscle cells (VSMC) respond to arterial wall injury by intimal proliferation and play a key role in atherogenesis by proliferating and migrating excessively in response to repeated injury, such as hypertension and atherosclerosis. In contrast, fully differentiated, quiescent VSMC allow arterial vasodilatation and vasoconstriction. Exaggerated and uncontrolled VSMC proliferation appears therefore to be a common feature of both atherosclerosis and hypertension. Signal transduction pathways in eukaryotic cells integrate diverse extracellular signals, and regulate complex biological responses such as growth, differentiation and death. One group of proline-directed Ser/Thr protein kinases, the mitogen-activated protein kinases (MAPKs), plays a central role in these signalling pathways. Much attention has focused in recent years on subfamilies of MAPKs, the extracellular signal regulated kinases (ERKs). Here we overview the work on ERKs 1 to 2, emphasising when possible their biological activities in VSMC proliferation. It is clear from numerous studies including our own, that ERK1/ERK2 pathway has an important role in VSMC proliferation induced by insulin (INS) and thrombin. Despite the physiological and pathophysiological importance of INS and thrombin, possible signal transduction pathways involved in INS and thrombin regulation of VSMC's proliferation remains poorly understood. Thus, this review examines recent findings in signaling mechanisms involved in INS and thrombin- triggered VSMC's proliferation with particular emphasis on ERK1/2 signaling pathways. Future investigations should now focus on the mechanisms of MAPK activation which might therefore represent a new mechanism involved in the antiproliferative effect revealed in this review.

Metabolic syndrome in HD patients: association with body composition, nutritional status, inflammation and serum iron

OBJECTIVE

Insulin resistance and metabolic syndrome (MeS) are common in end-stage renal disease (ESRD) patients on maintenance hemodialysis (HD). Such metabolic and clinical abnormalities may lead to an increased risk for cardiovascular disease.

METHODS

The study group included 22 well-nourished and 20 middle- to moderate-malnourished, stable ESRD patients, with median dialysis duration of 48 months (IQR 24.5-82.0). To determine nutritional status, body composition, inflammatory biomarkers and the presence of MeS subjective global assessment (SGA), anthropometrical measurements (BMI and waist circumference), bioelectrical impedance analysis (BIA), and biochemical parameters [the levels of serum albumin, cholesterol, HDL-cholesterol, triglyceride, hematocrit, hemoglobin, iron, TIBC, transferrin saturation (TSAT), ferritin, calcium, phosphorus, intact parathormone (i-PTH), TNF-alpha, IL-6 and high sensitivity C-reactive protein (hs-CRP)] were used. All parameters were evaluated by comparisons between two groups, with MeS (Group 2) and without it (Group 1). Logistical regression analysis was used to evaluate the correlation between measured variables and the presence of MeS in HD patients. Independent variables for MeS were identified by backward multivariate regression analysis. To identify the independent predictors for insulin resistance index (HOMA-IR) multivariate regression analysis was conducted, after linear regression analysis.

RESULTS

After adjustment for confounding variables, a model consisting of serum levels of iron, transferrin saturation (TSAT), and BMI which accounted for 62% of the variance in MeS, determined only BMI as an independent marker (according to ATP-III criteria). But, serum glucose level, iron, waist and total fat mass accounted for 68% of the variance in MeS, according to IDF criteria. Glucose level was an independent predictor. BMI and iron, as independent variables, contributed to 29% of the variance in IR HOMA, the sensitive marker of MeS.

CONCLUSION

The present study demonstrated that serum iron participated together with independent predictors, glucose and BMI, in the pathogenesis of IR and MeS of ESRD patients on maintenance HD.

Hypothetical mechanism of sodium pump regulation by estradiol under primary hypertension

Causal relationship between sodium and hypertension has been proposed and various changes in Na+,K+-ATPase (sodium pump) activity have been described in established primary hypertension. A number of direct vascular effects of estradiol have been reported, including its impact on the regulation of sodium pump activity and vasomotor tone. The effects of estradiol involve the activation of multiple signaling cascades, including phosphatydil inositol-3 kinase (PI3K) and p42/44 mitogen-activated protein kinase (p42/44(MAPK)). In addition, some of the effects of estradiol have been linked to activity of cytosolic phospholipase A(2) (cPLA(2)). One possible cardioprotective mechanism of estradiol involves of the interaction between estradiol and the rennin-angiotensin system (RAS). Elevated circulating and tissue levels of angiotensin II (Ang II) have been implicated in the development of hypertension and heart failure. The aim of our investigation was to elucidate the signaling mechanisms employed by estradiol and Ang II in mediating sodium pump, in vascular smooth muscle cells (VSMC). The aim of our investigation was to elucidate the signaling mechanisms employed by estradiol and Ang II in mediating sodium pump activity/expression in VSMC, with particular emphasis on PI3K/cPLA(2)/p42/44(MAPK) signaling pathways. Our primary hypothesis is that estradiol stimulates sodium pump activity/expression in VSMC via PI3K/cPLA(2)/p42/44(MAPK) dependent mechanism and, that impaired estradiol-stimulated sodium pump activity/expression in hypertensive rodent models (i.e. SHR), Ang II-mediated vascular impairment of estradiol is related to a decrease ability of estradiol to stimulate the PI3K/cPLA(2)/p42/44(MAPK) signaling pathways. An important corollary to this hypothesis is that in hypertensive state (i.e. SHR rats) the decreasing in ACE enzyme activity and/or AT1 receptor expression caused by administration of estradiol is accompanying with abrogated ability of Ang II to decrease IRS-1/PI3K association, and consequent PI3K/cPLA(2)/p42/44(MAPK) activity and associated sodium pump activity/expression. A clear characterization of how Ang II attenuates estradiol signaling may lead to a better understanding of the molecular mechanism(s) underlying pathophysiological conditions such as hypertension and to understanding how certain pathophysiological situations affect sodium pump activity/expression in VSMC.

Respiratory parameters in elite athletes--does sport have an influence?

INTRODUCTION

Unlike large population studies about cardiovascular components and how they adapt to intensive physical activity, there is less research into the causes of enlargement of the respiratory system in athletes (e.g. vital capacity, maximum flow rates and pulmonary diffusion capacity). The purpose of this research was to study and compare pulmonary function in different types of sports and compare them with controls in order to find out which sports improve lung function the most.

MATERIALS AND METHOD

Pulmonary functional capacities, vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and maximum voluntary ventilation (MVV) of 493 top athletes belonging to 15 different sports disciplines and of 16 sedentary individuals were studied. Pulmonary function test was performed according to ATS/ERS guidelines.

RESULTS

Basketball, water polo players and rowers had statistically higher vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1) than the healthy sedentary control individuals. Football and volleyball players had lower VC while FVC was higher in the football group compared to controls. Peak expiratory flow was lower in boxing, kayak, rugby, handball, taekwondo and tennis. The maximum voluntary ventilation (MVV) was significantly higher in water polo players and rowers. Boxers had statistically lower MVV than the controls. Players of other sports did not differ from the control group.

CONCLUSION

The study suggests that specific type of training used in basketball, water polo or rowing could have potential for improving pulmonary function and rehabilitation.

Nitric Oxide as a Marker for Levo-Thyroxine Therapy in Subclinical Hypothyroid Patients

Subclinical hypothyroidism (SH) is characterized by a mildly elevated concentration of thyroid stimulating hormone (TSH) despite free thyroxine (FT4) and triiodothyronine (FT3) levels within the reference range. Numerous studies revealed SH to be an independent risk factor for cardiovascular disease (CVD), including atherosclerosis, congestive heart failure, coronary heart disease, ischemic heart disease and the associated mortality. The relationship between SH and CVD is well documented, but the molecular mechanism underlying this correlation remain unknown. Endothelial dysfunction has been recognized as an initial step leading to CVD in patients with SH. Changes in lipid profile, inflammation and/or oxidative stress contribute to the endothelial dysfunction in SH. Moreover, the progression of SH is characterized by significantly decreased nitrite and nitrate levels. Recent animal and clinical studies discussed in this review suggest that nitric oxide (NO) levels could be a reliable biomarker for cardiovascular risk in SH. Understanding the regulation of NO production by thyroid hormone may provide novel and useful knowledge regarding how endothelial dysfunction in SH is linked with CVD and help us to uncover new treatments for SH. We suggest that serum NO level may be an indicator for the introduction and dosage of levothyroxine (LT4) replacement therapy in SH patients. Future studies should focus on understanding the molecular mechanisms underlying the effects of NO in physiological as well as in pathophysiological conditions such as hypothyroidism and their clinical relevance.

The Na+/K+-ATPase: A potential therapeutic target in cardiometabolic diseases

Cardiometabolic diseases (CMD) are a direct consequence of modern living and contribute to the development of multisystem diseases such as cardiovascular diseases and diabetes mellitus (DM). CMD has reached epidemic proportions worldwide. A sodium pump (Na+/K+-ATPase) is found in most eukaryotic cells' membrane and controls many essential cellular functions directly or indirectly. This ion transporter and its isoforms are important in the pathogenesis of some pathological processes, including CMD. The structure and function of Na+/K+-ATPase, its expression and distribution in tissues, and its interactions with known ligands such as cardiotonic steroids and other suspected endogenous regulators are discussed in this review. In addition, we reviewed recent literature data related to the involvement of Na+/K+-ATPase activity dysfunction in CMD, focusing on the Na+/K+-ATPase as a potential therapeutic target in CMD.

The protective role of nutritional antioxidants against oxidative stress in thyroid disorders

An imbalance between pro-oxidative and antioxidative cellular mechanisms is oxidative stress (OxS) which may be systemic or organ-specific. Although OxS is a consequence of normal body and organ physiology, severely impaired oxidative homeostasis results in DNA hydroxylation, protein denaturation, lipid peroxidation, and apoptosis, ultimately compromising cells' function and viability. The thyroid gland is an organ that exhibits both oxidative and antioxidative processes. In terms of OxS severity, the thyroid gland's response could be physiological (i.e. hormone production and secretion) or pathological (i.e. development of diseases, such as goitre, thyroid cancer, or thyroiditis). Protective nutritional antioxidants may benefit defensive antioxidative systems in resolving pro-oxidative dominance and redox imbalance, preventing or delaying chronic thyroid diseases. This review provides information on nutritional antioxidants and their protective roles against impaired redox homeostasis in various thyroid pathologies. We also review novel findings related to the connection between the thyroid gland and gut microbiome and analyze the effects of probiotics with antioxidant properties on thyroid diseases.

Diabetic cardiomyopathy: The role of microRNAs and long non-coding RNAs

Diabetes mellitus (DM) is on the rise, necessitating the development of novel therapeutic and preventive strategies to mitigate the disease's debilitating effects. Diabetic cardiomyopathy (DCMP) is among the leading causes of morbidity and mortality in diabetic patients globally. DCMP manifests as cardiomyocyte hypertrophy, apoptosis, and myocardial interstitial fibrosis before progressing to heart failure. Evidence suggests that non-coding RNAs, such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), regulate diabetic cardiomyopathy-related processes such as insulin resistance, cardiomyocyte apoptosis and inflammation, emphasizing their heart-protective effects. This paper reviewed the literature data from animal and human studies on the non-trivial roles of miRNAs and lncRNAs in the context of DCMP in diabetes and demonstrated their future potential in DCMP treatment in diabetic patients.

Association of blood pressure and metabolic syndrome components with magnesium levels in drinking water in some Serbian municipalities

Chronic exposure to insufficient levels of magnesium (Mg) in drinking water increases the risk of magnesium deficiency and its association with hypertension, dyslipidemia and type 2 diabetes mellitus. The aim of the study was to assess the potential association of mineral contents in drinking water with blood pressure and other components of metabolic syndrome (MetS) (BMI as measure of obesity, triglycerides, glucose, and insulin resistance, index-HOMA IR), in a healthy population. This study was conducted in three randomly selected municipalities (Pozarevac, Grocka and Banovci), and recruited 90 healthy blood donors, aged 20-50 years. The Pozarevac area had a four times higher mean Mg level in drinking water (42 mg L(-1)) than Grocka (11 mg L(-1)). Diastolic blood pressure was lowest in subjects from Pozarevac. Serum Mg (sMg) was highest, and serum Ca(2+)/Mg (sCa/Mg) lowest in subjects from Pozarevac, and after adjustment for confounders (age, gender, BMI), only total cholesterol and sMg levels were independent predictors of diastolic blood pressure, sMg levels were independent predictors of triglycerides, and sCa/Mg predicted glucose levels. These results suggest that Mg supplementation in areas of lower magnesium levels in drinking water may be an important measure in the prevention of hypertension and MetS in general.

Effects of levothyroxine replacement therapy on parameters of metabolic syndrome and atherosclerosis in hypothyroid patients: a prospective pilot study

The aim of this study was to investigate the effect of levothyroxine (LT4) replacement therapy during three months on some parameters of metabolic syndrome and atherosclerosis in patients with increased thyroid-stimulating hormone (TSH) level. This study included a group of 30 female patients with TSH level >4 mIU/L and 15 matched healthy controls. Intima media complex thickness (IMCT) and peak systolic flow velocity (PSFV) of superficial femoral artery were determined by Color Doppler scan. In hypothyroid subjects, BMI, SBP, DBP, and TSH were significantly increased versus controls and decreased after LT4 administration. FT4 was significantly lower in hypothyroid subjects compared with controls and significantly higher by treatment. TC, Tg, HDL-C, and LDL-C were similar to controls at baseline but TC and LDL-C were significantly decreased by LH4 treatment. IMCT was significantly increased versus controls at baseline and significantly reduced by treatment. PSFV was similar to controls at baseline and significantly decreased on treatment. In this study, we have demonstrated the effects of LT4 replacement therapy during three months of treatment on correction of risk factors of metabolic syndrome and atherosclerosis.

Regulation of nitric oxide production in hypothyroidism

Hypothyroidism is a common endocrine disorder that predominantly occurs in females. It is associated with an increased risk of cardiovascular diseases (CVD), but the molecular mechanism is not known. Disturbance in lipid metabolism, the regulation of oxidative stress, and inflammation characterize the progression of subclinical hypothyroidism. The initiation and progression of endothelial dysfunction also exhibit these changes, which is the initial step in developing CVD. Animal and human studies highlight the critical role of nitric oxide (NO) as a reliable biomarker for cardiovascular risk in subclinical and clinical hypothyroidism. In this review, we summarize the recent literature findings associated with NO production by the thyroid hormones in both physiological and pathophysiological conditions. We also discuss the levothyroxine treatment effect on serum NO levels in hypothyroid patients.

Non-alcoholic fatty liver disease, metabolic syndrome, and type 2 diabetes mellitus: where do we stand today?

Non-alcoholic fatty liver disease (NAFLD), metabolic syndrome (MetS), and type 2 diabetes (T2DM) are metabolic disorders that belong to a highly prevalent disease cluster with a significant impact on public health worldwide. MetS is a complex condition characterized by metabolism perturbations that include glucose intolerance, insulin resistance, dyslipidaemia, associated pro-inflammatory state, and arterial hypertension. Because the components of MetS commonly co-occur, the management of these disorders cannot be considered separate issues. Thus NAFLD, recognized as a hepatic manifestation of MetS, is frequently associated with T2DM. This review analyses the underlying connections between these diseases and the risks associated with their co-occurrence. The effective management of NAFLD associated with MetS and T2DM involves an early diagnosis and optimal treatment of each condition leading to improvement in glycaemic and lipid regulation, liver steatosis, and arterial hypertension. The net effect of such treatment is the prevention of atherosclerotic cardiovascular diseases and liver fibrosis.

Effects of Metformin-Single Therapy on the Level of Inflammatory Markers in Serum of Non-Obese T2DM Patients with NAFLD

BACKGROUND AND OBJECTIVES

Non-alcoholic fatty liver disease (NAFLD) is associated with inflammation and subsequent increase in cardiovascular risk. Because of its widespread presence and distribution, invasive diagnostic procedures (i.e., liver biopsy) are reserved for a limited number of subjects. With liver ultrasound, Fatty liver index (FLI) and fibrosis-4 (FIB-4) scores non-invasively assess liver steatosis and fibrosis. We aimed to evaluate the changes in inflammatory markers and FLI/FIB-4 scores in non-obese metformin-treated type 2 diabetes patients (T2DM) with NAFLD.

METHODS

All subjects underwent abdominal ultrasound aiming for NAFLD stratification (grade 1 to 3 according to its severity). Metabolic parameters (morning glycaemia, HbA1C, lipids, liver function tests), serum inflammatory markers (C-reactive protein, ferritin, and nitric oxide) and FLI/- FIB-4 were calculated.

RESULTS

FLI score and ultrasound NAFLD grades were found to correlate (p<0.05). We observed a significant correlation between the levels of ferritin and C-reactive protein (CRP) (p<0.05), and the FLI (p<0.05). Body weight (BW) (p<0.05), waist circumference (WC) (p<0.05), the levels of HbA1c (p<0.05), transferrin (p<0.05), insulin (p<0.05), and FLI score (p<0.05) significantly differed between groups as defined by the severity of NAFLD.

CONCLUSION

This pilot study suggests that the serum inflammatory markers at the average normal values point to the sufficiency of metformin-single therapy in inflammation control in non-obese T2DM patients with NAFLD.

New biomarkers: prospect for diagnosis and monitoring of thyroid disease

After the metabolic syndrome and its components, thyroid disorders represent the most common endocrine disorders, with increasing prevalence in the last two decades. Thyroid dysfunctions are distinguished by hyperthyroidism, hypothyroidism, or inflammation (thyroiditis) of the thyroid gland, in addition to the presence of thyroid nodules that can be benign or malignant. Thyroid cancer is typically detected via an ultrasound (US)-guided fine-needle aspiration biopsy (FNAB) and cytological examination of the specimen. This approach has significant limitations due to the small sample size and inability to characterize follicular lesions adequately. Due to the rapid advancement of high-throughput molecular biology techniques, it is now possible to identify new biomarkers for thyroid neoplasms that can supplement traditional imaging modalities in postoperative surveillance and aid in the preoperative cytology examination of indeterminate or follicular lesions. Here, we review current knowledge regarding biomarkers that have been reliable in detecting thyroid neoplasms, making them valuable tools for assessing the efficacy of surgical procedures or adjunctive treatment after surgery. We are particularly interested in providing an up-to-date and systematic review of emerging biomarkers, such as mRNA and non-coding RNAs, that can potentially detect thyroid neoplasms in clinical settings. We discuss evidence for miRNA, lncRNA and circRNA dysregulation in several thyroid neoplasms and assess their potential for use as diagnostic and prognostic biomarkers.

Early Effects of Hyperbaric Oxygen on Inducible Nitric Oxide Synthase Activity/Expression in Lymphocytes of Type 1 Diabetes Patients: A Prospective Pilot Study

This study aimed at examining the early effects of hyperbaric oxygen therapy (HBOT) on inducible nitric oxide synthase (iNOS) activity/expression in lymphocytes of type 1 diabetes mellitus (T1DM) patients. A group of 19 patients (mean age: 63 ± 2.1) with T1DM and with the peripheral arterial disease were included in this study. Patients were exposed to 10 sessions of HBOT in the duration of 1 h to 100% oxygen inhalation at 2.4 ATA. Blood samples were collected for the plasma C-reactive protein (CRP), plasma free fatty acid (FFA), serum nitrite/nitrate, and serum arginase activity measurements. Expression of iNOS and phosphorylation of p65 subunit of nuclear factor-κB (NFκB-p65), extracellular-regulated kinases 1/2 (ERK1/2), and protein kinase B (Akt) were examined in lymphocyte lysates by Western blot. After exposure to HBOT, plasma CRP and FFA were significantly decreased (p < 0.001). Protein expression of iNOS and serum nitrite/nitrate levels were decreased (p < 0.01), while serum arginase activity was increased (p < 0.05) versus before exposure to HBOT. Increased phosphorylation of NFκB-p65 at Ser536 (p < 0.05) and decreased level of NFκB-p65 protein (p < 0.001) in lymphocytes of T1DM patients were observed after HBOT. Decreased phosphorylation of ERK1/2 (p < 0.05) and Akt (p < 0.05) was detected after HBOT. Our results indicate that exposure to HBO decreased iNOS activity/expression via decreasing phosphorylation of ERK1/2 and Akt followed by decreased activity of NFκB.

Effect of Hyperbaric Oxygen Therapy on Fatty Acid Composition and Insulin-like Growth Factor Binding Protein 1 in Adult Type 1 Diabetes Mellitus Patients: A Pilot Study

OBJECTIVE

Metabolic changes in type 1 diabetes mellitus (T1DM) impair vasodilation, and this leads to tissue hypoxia and microvascular pathology. Hyperbaric oxygen therapy (HBOT) can significantly improve the outcome of ischemic conditions in T1DM patients and reduce vascular complications. The aim of our study was to assess the effects of HBOT on plasma fatty acid (FA) composition, and expression of insulin-like growth factor binding protein 1 (IGFBP-1) in T1DM patients.

METHODS

Our study included 24 adult T1DM patients diagnosed with peripheral vascular complications. The patients were exposed to 10 sessions of 100% oxygen inhalation at 2.4 atmosphere absolute for 1 hour. Blood samples were collected at admission and after HBOT for measurement of metabolic parameters, FA composition and IGFBP-1. Measurement of plasma FA composition was determined by gas chromatography. Expression of IGFBP-1 in the serum was estimated by Western blot analysis.

RESULTS

HBOT decreased blood levels of total cholesterol (p<0.05), triglycerides (p<0.05) and low-density lipoprotein (p<0.05). HBOT increased plasma levels of individual FAs: palmitic acid (p<0.05), palmitoleic acid (p<0.05), docosapentaenoic acid (p<0.05) and docosahexaenoic acid (p<0.01), and decreased levels of stearic acid (p<0.05), alpha linolenic acid (p<0.05) and linoleic acid (p<0.01). Expression of IGFBP-1 (p<0.01) was increased, whereas the level of insulin (p<0.001) was decreased in the serum after HBOT.

CONCLUSIONS

Our results indicate that HBOT exerts beneficial effects in T1DM patients by improving the lipid profile and altering FA composition.

HbA1C as a marker of retrograde glycaemic control in diabetes patient with co-existed beta-thalassaemia: A case report and a literature review

WHAT IS KNOWN AND OBJECTIVE

The HbA1C marker used in assessing diabetes control quality is not sufficient in diabetes patients with thalassaemia.

CASE DESCRIPTION

A male diabetic patient with thalassaemia was hospitalized due to distal neuropathic pain, right toe trophic ulcer, unacceptable five-point glycaemic profile and recommended HbA1C value. After simultaneously initiated insulin therapy and management of ulcer by hyperbaric oxygen, the patient showed improved glycaemic control and ulcer healing, which led to the patient's discharge.

WHAT IS NEW AND CONCLUSION

In thalassaemia and haemoglobinopathies, due to discrepancies in the five-point glycaemic profile and HbA1C values, it is necessary to measure HbA1C with a different method or to determine HbA1C and fructosamine simultaneously.