Clinical Diabetology (ISSN 2450-7458) is published six times a year by "Via Medica sp. z o.o." sp.k.

Vitamin D is formed in human epithelial cells via photochemical synthesis and is also acquired from dietary sources. The so-called classical effect of this vitamin involves the regulation of calcium homeostasis and bone metabolism. Apart from this, non-classical effects of vitamin D have recently gained renewed attention. One important yet little known of the numerous functions of vitamin D is the regulation of nervous system development and function. The neuroprotective effect of vitamin D is associated with its influence on neurotrophin production and release, neuromediator synthesis, intracellular calcium homeostasis, and prevention of oxidative damage to nervous tissue. Clinical studies suggest that vitamin D deficiency may lead to an increased risk of disease of the central nervous system (CNS), particularly schizophrenia and multiple sclerosis. Adequate intake of vitamin D during pregnancy and the neonatal period seems to be crucial in terms of prevention of these diseases.

Glucose metabolism disorders influence anticarcinogenic function of natural killer (NK) cells. The aim of this study was to evaluate the number and cytotoxic activity of NK cells in type 2 diabetic (T2D) patients with negative family history of cancer, type 2 diabetic subjects with newly diagnosed untreated colon cancer (T2DCC) and patients without type 2 diabetes with newly diagnosed, untreated colon cancer (CC). Incubation tests were performed in 18 T2D patients, treated with diet and oral antidiabetic agents, 16 T2DCC; cT1-4N0M0 (c-clinical diagnosis based on computed tomography, colonoscopy and histopathology) treated with diet and oral antidiabetic agents and 16 normoglycemic CC; cT1-4N0M0. Control group included 18 metabolically healthy (with normal fasting glucose and normal glucose tolerance) subjects (HS) with negative family history of cancer, matched by age, BMI and waist circumference. Peripheral blood mononuclear cells were isolated by means of gradient centrifugation. The K562 human erythroleukemia cell line served as the standard target for human NK cytotoxicity assay. The T2D revealed an increased number of NK cells (13.56 ± 5.9 vs 9.50 ± 4.8 %; p < 0.05) when compared with HS, yet these cells had a decreased activity (3.3 ± 2.5 vs 9.4 ± 3.6 %; p < 0.01). The CC demonstrated a decreased activity (2.9 ± 1.8 %; p < 0.01) but a similar number (8.82 ± 3.7 %; not significant) of NK cells when compared to HS. The T2DCC NK cells were characterized by trace cytotoxic activity (1.1 ± 0.7 %; p < 0.01) and nearly three times greater amount (21.24 ± 7.5 %; p < 0.01) when compared to T2D. Type 2 diabetes and CC are associated with disadvantageous alterations of NK cells, leading to impairment in their cytotoxic activity. The impaired activity of NK cells in T2D can be involved in the increased carcinogenic risk and can promote a higher incidence of CC.

Diabetes and cancer are diseases which take the size of an epidemic spread across the globe. Those diseases are influenced by many factors, both genetic and environmental. Precise knowledge of the complex relationships and interactions between these two conditions is of great importance for their prevention and treatment. Many epidemiological studies have shown that certain types of cancer, especially gastrointestinal cancers (pancreas, liver, colon) and also the urinary and reproductive system cancers in women are more common in patients with diabetes or related metabolic disorders. There are also studies showing the inverse relationship between diabetes and cancer, or the lack of it, but they are less numerous and relate mainly to prostate cancer or squamous cell carcinoma of the esophagus. Epidemiological studies, however, do not say anything about the mechanisms of these dependencies. For this purpose, molecular research is needed on the metabolism of cells (including tumor cells) and on metabolic dysfunctions that arise due to changes in the cell environment taking place in the sick, as well as in the intensely treated human organism.

Aims To assess the prevalence and time trends of diabetic retinopathy (DR) in the overall population of Poland from 2013 to 2017 and diagnose the risk factors of occurring DR among patients with diabetes mellitus (DM). Methods Data from all levels of healthcare services at public and private institutions recorded in the National Health Fund (NHF) database were evaluated. International Classification of Diseases codes (ICD-9 and ICD-10) and unique NHF codes were used to identify DM type 1 and type 2 patients, DR and treatment procedures including laser photocoagulation, pars plana vitrectomy (PPV), anti-VEGF and steroid intravitreal injections. Results The overall registered prevalence of DR in the entire population of Poland was 0.81%. The mean prevalence of DR was 20.01% in the population with type 1 DM and 9.70% in the population with type 2 DM. In the study period, women represented 56.36% of all individuals registered with DR and 55.09% of all DM patients. In Poland, only 6.34% of all DM patients with DR received specific treatment with laser photocoagulation of the retina (82.32%), PPV (11.56%), anti-VEGF or steroid injections (5.15% and 0.97%, respectively). Cox regression hazard analysis showed that the risk of DR was associated with DM treatment only by GPs, female sex, coexisting systemic diseases and urban residence in both type 1 and type 2 DM. Conclusions A 5-year retrospective analysis reveals the mean prevalence of DR in the population with type 1 and type 2 DM in Poland was rather low.

Background Patients with prediabetes are at risk for diabetes, cardiovascular events, and microvascular complications. The rtx1 (Imagine Eyes, France) permits early detection of changes in the retinal photoreceptors and vessels. Objective Cone parameters and retinal microvasculature were analyzed with the rtx1 in 12 prediabetic patients and 22 healthy subjects. The analysis was based on cone density (DM), interphotoreceptor distance (SM), cone packing regularity, and retinal vessel parameters: wall thickness, lumen diameter (LD), wall-to-lumen ratio (WLR), and cross-sectional area of the vascular wall. Results DM in the prediabetic group was not significantly lower than that in the control group (18,935 ± 1713 cells/mm2 and 19,900 ± 2375 cells/mm2, respectively; p = 0.0928). The LD and WLR means differed significantly between the prediabetic and the control groups (LD 94.3 ± 10.9 versus 101.2 ± 15, p = 0.022; WLR 0.29 ± 0.05 versus 0.22 ± 0.03, p < 0.05). A multivariate regression analysis showed that the WLR was significantly correlated with BMI and total cholesterol. Conclusions Abnormalities found in rtx1 examinations indicated early signs of arteriolar dysfunction, prior to impaired glucose tolerance progressing to diabetes. The rtx1 retinal image analysis offers noninvasive measurement of early changes in the vasculature that routine clinical examination cannot detect.

The aim of this study was to investigate the incidence of hypogonadotropic hypogonadism (HH) in type 2 diabetic men (T2DM) in population of Polish men and examine the possible influence of estradiol levels and glycemic control. We evaluated TT, cfT, estradiol, and glycemic control (HbA1c) in 184 diabetic men and in 149 nondiabetic control group. The mean HbA1c was 8.6 ± 0.2% and 6.1 ± 0.3% and cfT concentration was 0.315 ± 0.08 nmol/L and 0.382 ± 0.07 nmol/L, respectively. T2DM had higher E2 concentration than nonobese control men (29.4 ± 3.7 pg/mL versus 24.5 ± 2.9 pg/mL). Forty-six percent of T2DM were hypogonadal and 93% had HH. We observed inverse relationship between BMI and cfT (r = −0.341, P < 0.01) and positive between BMI and E2 (r = 0.329, P < 0.01). E2 concentration was higher in T2DM with HH versus T2DM with normal TT/cfT concentration (34.5 ± 5.2 versus 27.4 ± 3.4 pg/mL). We observed negative correlation between HbA1c and cfT (r = −0.336, P < 0.005) but positive between HbA1c and E2 levels (r = 0.337, P < 0.002). The prevalence of obesity, hypertension, and CVD was higher in men with hypogonadism. High incidence of hypogonadotropic hypogonadism in type 2 diabetic men in Polish population is associated with poor glycemic control and can be secondary to an increase in estradiol concentrations.

Introduction: The objective of this study was to evaluate glucose transport into lymphocytes in healthy subjects and patients with type 2 diabetes mellitus (DM) treated either with diet only or with insulin and to propose peripheral blood lymphocytes as a convenient model for cellular glucose transport studies. Materials and Methods: Sixty subjects with type 2 DM, 30 treated with diet only and 30 with insulin, were investigated. Thirty healthy subjects matched for age, weight, and sex served as a control group. Deoxy-D-glucose, 2-[ 3 H(G)] transport was studied in isolated peripheral blood lymphocytes. Expression of glucose transporters was ascertained by immunocytochemical identification and by Western blotting. Results: In lymphocytes from the control group, deoxy-D-glucose uptake increased gradually with the duration of the experiment. In diabetics treated with insulin, the maximal increase in deoxy-D-glucose uptake was observed after 30 min of the investigation, followed by a plateau phase. In diabetics treated with diet, deoxy-D-glucose uptake increased slowly during the first 30 min. The presence of GLUT1 and GLUT3 in lymphocytes was confirmed in this study. Conclusions: Glucose transport into lymphocytes is altered in type 2 DM. In lymphocytes from diabetics, the dynamics of deoxy-D-glucose uptake significantly differed from that in healthy subjects. There was also a significant difference between the diabetic groups, representing different modes of therapy and stages of the disease. Glucose transport into lymphocytes is apparently influenced by DM as well as by the mode of therapy. We suggest that peripheral blood lymphocytes may become a promising model for studies on glucose transport in diabetes.