Insulin resistance – the basics every medical specialist should know

Introduction and purpose: Insulin resistance (IR) is a health problem as it can accompany obesity and lead to serious metabolic complications. In recent years, it has been "overdiagnosed" in clinical practice due to the lack of specific diagnostic criteria. The article summarizes the current knowledge in the field of pathophysiology, clinical picture and diagnostics. State of knowledge: Obesity remains the leading cause of IR, especially in the 21st century. In a positive energy balance, the adipocyte overloaded with fat protects itself against further influx of glucose and fats and becomes insulin insensitive. A component of IR development is subclinical inflammation of macrophage-rich adipose tissue which is exacerbated by an adipocytokine imbalance, which in turn generates IR. The markers of cellular resistance to insulin are free fatty acids in the bloodstream which are responsible for the lipotoxicity in hepatocytes and myocytes. Compensatory fasting hyperinsulinemia, which is currently considered the most sensitive diagnostic criterion, provides evidence of IR. An effective method of sensitizing cells to insulin is lifestyle modification, including a low-energy diet with regular physical activity in the form of aerobic-resistance exercise. Literature recommends no pharmacological treatment of IR alone, without obesity or other concomitant diseases. Conclusions: IR is not a separate disease, but only a pathological expression of cells' adaptation to excess of consumed energy. However, in its systemic form, when the protective mechanisms become ineffective, it induces metabolic disturbances. Only the causal treatment of IR guarantees therapeutic success

Is water fluoridation correlated with hypothyroidism?

Introduction: Hypothyroidism is a global health problem. Primary thyroid hormone deficiency may be caused by a wide spectrum of health problems, e.g. chronic autoimmune thyroiditis, postpartum thyroiditis, iodine deficiency, thyroid or parathyroid surgery and drugs. In recent years, scientific studies have also been published indicating a correlation between excessive intake of fluoride and hypothyroidism. Fluoride is added to the water sources of many countries. Objective: The purpose of the study was to review and compare currently available data on PubMed about fluoride-induced hypothyroidism. A brief description of the state of knowledge: Evidence based knowledge suggests that there is a potential relationship between water fluoridation and endocrine system disorders, especially hypothyroidism. Current studies indicate that TSH hormone levels get elevated with increased fluoride intake. The reason is supposed to be that fluorine is more electronegative than iodine and therefore easily displaces iodine from the body, thus affecting thyroid function. Conclusions: Current studies do not clearly show a simple correlation between excessive fluoridation of drinking water and the occurrence of hypothyroidism. However, inconclusive scientific evidence and the prevalence of hypothyroidism in the population indicate the need for further research in this area

Link between Insulin Resistance and Obesity—From Diagnosis to Treatment

Insulin resistance (IR) has become a common health issue in medical practice. There are no detailed data on IR prevalence, but it is an increasing problem due to its close association with obesity. However, IR is not considered as a separate nosological entity and the diagnostic criteria are not well defined, which leads to overdiagnosis of IR and an inappropriate approach. This review aims to summarize the available literature on IR pathophysiology, its relationship with obesity, as well as diagnostic methods, clinical presentation and treatment. Excessive energy intake results in cell overload that triggers mechanisms to protect cells from further energy accumulation by reducing insulin sensitivity. Additionally, hypertrophied adipocytes and macrophage infiltration causes local inflammation that may result in general inflammation that induces IR. The clinical picture varies from skin lesions (e.g., acanthosis nigricans) to metabolic disorders such as diabetes mellitus or metabolic-associated fatty liver disease. There are numerous IR laboratory markers with varying sensitivities and specificities. Nutrition changes and regular physical activity are crucial for IR management because a reduction in adipose tissue may reverse the inflammatory state and consequently reduce the severity of insulin resistance. In cases of obesity, anti-obesity medications can be used

Functional Magnetic Resonance Imaging and Obesity—Novel Ways to Seen the Unseen

Obesity remains a pandemic of the 21st century. While there are many causes of obesity and potential treatments that are currently known, source data indicate that the number of patients is constantly increasing. Neural mechanisms have become the subject of research and there has been an introduction of functional magnetic resonance imaging in obesity-associated altered neural signaling. Functional magnetic resonance imaging has been established as the gold standard in the assessment of neuronal functions related to nutrition. Thanks to this, it has become possible to delineate those regions of the brain that show altered activity in obese individuals. An integrative review of the literature was conducted using the keywords ““functional neuroimaging” OR “functional magnetic resonance “OR “fmri” and “obesity” and “reward circuit and obesity” in PubMed and Google Scholar databases from 2017 through May 2022. Results in English and using functional magnetic resonance imaging to evaluate brain response to diet and food images were identified. The results from functional magnetic resonance imaging may help to identify relationships between neuronal mechanisms and causes of obesity. Furthermore, they may provide a substrate for etiology-based treatment and provide new opportunities for the development of obesity pharmacotherapy

Comparison of Catalytic Properties of Vanadium Centers Introduced into BEA Zeolite and Present on (010) V2O5 Surface–DFT Studies

Vanadium-based catalysts, in which vanadium is present either as bulk V2O5 or as isolated species, are active in numerous oxidation reactions. In the present study, vanadium speciation and the possibility of its introduction in various forms (V=O, V–OH, V(=O)(–OH)) into the structurally different crystallographic positions in BEA zeolite was considered by means of Density Functional Theory (DFT). Out of nine nonequivalent positions, T2 and T3 positions are the most preferred. The former may accommodate V=O or V–OH, the latter V–OH or V(=O)(–OH). The structural and electronic properties of all possible centers present in the BEA zeolite are then compared with the characteristics of the same species on the most abundant (010) V2O5 surface. It is demonstrated that they exhibit higher nucleophilic character when introduced into the zeolite, and thus, may be more relevant for catalysis