Iwona Kaznowska-Bystryk

Omentin - a new adipokine with many roles to play

Abstract Adipose tissue is at a point of high interest in medical research, not only as an energy depot, but also because it secretes nearly more than 600 cytokines. These are termed‚ adipokines’. Human adipokines are involved in numerous metabolic processes, including the regulation of appetite, energy expenditure, insulin sensitivity, inflammation and cardiovascular activity. Thus, these could be clinically important as a markers of adipose tissue function and increased metabolic risk. The search for novel adipokines linking obesity to related co-morbidities has become a major topic in obesity research. In such work, there is an increasing need to define their function, their molecular targets and their potential clinical relevance as biomarkers or in the treatment of obesity and other metabolic diseases. Omentin (34 kDa) is a recently identified fat deposition-specific adipokine with multiple interactions. Concentrations of omentin have been shown to be decreased in patients with obesity and impaired glucose regulation, in patients afflicted with diabetes type 1 and 2, and in patients with polycystic ovary syndrome. These are all diseases commonly associated with insulin resistance and obesity. The aim of this study was to show and compare the latest information about omentin and its relationships with obesity, diabetes mellitus (DM), metabolic syndrome (MetS), inflammation, cardiac problems, sex hormone imbalances and cancer. The association of omentin with particular metabolic indexes may suggest that an elevation in omentin level may be seen as being a marker for leanness, while a decreased level will underline possible situations of overweight and obesity along with their comorbidities (diabetes, cardiovascular disease, metabolic syndrome, inflammation and even cancer). However, a challenge for the future is to fully understand the multiple role played by omentin. Thus, more studies in these matter are required.

Association between concentration of melatonin, and lipoproteins, LPO, hsCRP, NTproBNP in chronic heart failure patients

ABSTRACT The aim of the study was to examine concentrations and relationships between melatonin levels assessed at 0:200 hrs and 0:700 hrs, lipid hydroperoxide (LPO) assessed at 0:200 hrs and 0:700 hrs, and apolipoprotein (apo)AI, apoAII, apoB, high sensitivity C-reactive protein (hsCRP) and NT-proBNP, in 27 patients with chronic heart failure (CHF) (17 patients - with NYHA class II and 10 - with NYHA class III). In the study, Lipoproteins apoAI, apoAII, apoB, high sensitivity C-reactive protein (hsCRP) levels were determined by way of immunonephelometric methods, serum melatonin concentration was measured by using a competitive enzyme immunoassay technique, while serum LPO concentration was measured by using Cayman’s Lipid Hydroperoxide Assay Kit. In the study, CHF patients without acute inflammatory response demonstrated a decreased concentration of high density lipoprotein cholesterol (HDL-C), apoAI, apoAII levels, but an increased concentration of NT-proBNP, hsCRP and LPO at night, and LPO at daytime; however, the concentration of LPO at 0:700 was lower than at 0:200. Pearson’s correlation test and multiple ridge stepwise regression showed that melatonin administered at night exerts an effect on the composition of apoAI and apoAII of HDL particles, and induces decreased LPO at 0:700, but has no effect upon NT-proBNP levels in patients with NYHA class II. However, in patients with NYHA class III, melatonin administered at night induces an increase in the content of apoAII and apoAI, which further decreases hsCRP, and this, together with the administered melatonin, brings about daytime decreases in NT-proBNP and hsCRP levels. The results indicated that the content of apoAII and apoAI in HDL particles and melatonin demonstrate an anti-oxidative and anti-inflammatory effect, and together, have a cardio-protective effect on patients with advanced CHF. Hence, the results support melatonin being a cardio-protective agent. These relationships, however, need to be confirmed in further studies.

The heparan sulfate and its diverse biological activities

Abstract Heparan sulfate (HS) is one of the most common glycosaminoglycan (GAG) in mammals. It is composed of relatively simple disaccharide subunits, which, by further modification, such as sulfation and epimerization, potentially offer huge diversity in biological function. GAG chains of different length, different patterns of sulfation, and other modifications, depending on location, generate unique forms. Due to polyanion charges, these compounds can interact with other molecules, such as proteins, cytokines, chemokines and growth factors, both on the cell surface and inside the extracellular matrix. These interactions serve protective and storage functions for the compounds, safeguarding them from proteolysis. In this way, HS is involved in numerous signaling pathways, and in growth and differentiation processes. Disrupted interactions between the HS and growth factors, cytokines or other proteins have been observed in various disorders, among these Alzheimer’s disease, epilepsy, atherosclerosis, diabetes, and cancer processes. Detailed knowledge of these relationships at the molecular level will allow researchers to understand the mechanisms underlying these disorders and enable the development of effective therapeutic strategies.