Hypertension is a serious condition that can lead to many health problems. The mechanisms underlying this process are still not fully understood. The kynurenine pathway may be involved in the occurrence and progression of hypertension. The purpose of this study was to examine the activity of peripheral kynurenine pathway in rats with renovascular hypertension in Goldblatt 2K1C model. Hypertension was induced in the experimental groups by constricting the renal artery of the left kidney of the rats. Determination of tryptophan (Trp) and kynurenine pathway metabolites was assessed by high-performance liquid chromatography in plasma and tissues obtained at 4, 8, and 16 weeks after the surgical intervention or sham surgery. Levels of Ang II were evaluated using commercial immuno-enzymatic ELISA kits. Surgical treatment led to increased values of mean blood pressure and systolic blood pressure, whereas Trp concentrations were decreased in experimental animals compared to appropriate controls. Simultaneously, the considerable increment of kynurenine pathway components and a significant increase in the activity of tryptophan 2,3-dioxygenase were observed in rats with developed hypertension in comparison with controls. There were no differences between Ang II levels in controls and experimental groups. The inverse relationship was between plasma Trp and both SBP and Ang II values, and Trp independently affected Ang II concentrations in hypertensive rats. In contrast, tryptophan 2,3-dioxygenase activity and plasma kynurenine metabolites positively correlated with blood pressure values as well as with Ang II levels in these animals. Moreover, kynurenine was independently connected with MBP. Renovascular hypertension influences kynurenine pathway and leads to an imbalance in Trp and its metabolite levels. Tryptophan 2,3-dioxygenase and part of the kynurenine metabolites in plasma and tissues positively correlated with blood pressure values and Ang II levels. Although the mechanisms underlying this phenomenon are unclear, our experiment showed a link between renovascular hypertension and activation of kynurenine pathway. Impact statement As hypertension is a major health problem, our research has focused on the connection between the kynurenine pathway and hypertension. We assessed the levels of the main metabolites of dietary tryptophan and analyzed its levels in terms of high blood pressure. The results of our work indicated that in the renovascular rat's model of hypertension, an alteration of the kynurenine pathway occurred. According to our knowledge, this is the first study that has investigated in a comprehensive manner the alteration of the kynurenine pathway under the condition of elevated blood pressure. On the one hand, the work supports a better understanding of pathophysiological basics of the occurrence of hypertension, and on the other hand it provides potential opportunities to treat this disease.

The exact roles of adipokines in the pathogenesis of type 2 diabetes and obesity are still unclear. The aim of the study was to evaluate fatty acid binding protein 4 (FABP4) concentrations in the serum and urine of women with excessive gestational weight gain (EGWG) and gestational diabetes mellitus (GDM) in the early post-partum period, with reference to their laboratory test results, body composition, and hydration status. The study subjects were divided into three groups: 24 healthy controls, 24 mothers with EGWG, and 22 GDM patients. Maternal body composition and hydration status were evaluated by the bioelectrical impedance analysis (BIA) method. Concentrations of FABP4, leptin, and ghrelin were determined via enzyme-linked immunosorbent assay (ELISA). Healthy women were characterized by the lowest serum leptin concentrations and by a negative correlation between the serum and urine FABP4 levels. Serum FABP4 levels were the highest in the GDM group. Serum FABP4 and leptin concentrations correlated positively in the GDM group. The EGWG group had the highest degree of BIA disturbances in the early puerperium and positive correlations between the urine FABP4 and serum leptin and ghrelin concentrations. The physiological and pathological significance of these findings requires further elucidation.

Fetuses exposed to gestational diabetes mellitus (GDM) have a higher risk of abnormal glucose homeostasis in later life. The molecular mechanisms of this phenomenon are still not fully understood. Fatty acid binding protein 4 (FABP4) appears to be one of the most probable candidates involved in the pathophysiology of GDM. The main aim of the study was to investigate whether umbilical cord serum FABP4 concentrations are altered in term neonates born to GDM mothers. Two groups of subjects were selected—28 healthy controls and 26 patients with GDM. FABP4, leptin, and ghrelin concentrations in the umbilical cord serum, maternal serum, and maternal urine were determined via an enzyme-linked immunosorbent assay. The umbilical cord serum FABP4 levels were higher in the GDM offspring and were directly associated with the maternal serum FABP4 and leptin levels, as well as the prepregnancy body mass index (BMI) and the BMI at and after delivery; however, they correlated negatively with birth weight and lipid parameters. In the multiple linear regression models, the umbilical cord serum FABP4 concentrations depended positively on the maternal serum FABP4 and negatively on the umbilical cord serum ghrelin levels and the high-density lipoprotein cholesterol. There are many maternal variables that can affect the level of FABP4 in the umbilical cord serum, thus, their evaluation requires further investigation.

Gestational diabetes mellitus is one of the most often medical conditions during pregnancy affecting 5-6% of all pregnancies. The etiology of gestational diabetes is not clearly understood. In obesity and diabetes mellitus type 2, abnormal insulin signaling is an important agent mediating the increase of insulin resistance. Insulin receptor substrate serine phosphorylation is a time-controlled physiological reaction in insulin signaling that has been disrupted by metabolic and inflammatory stresses to support insulin resistance. Several kinases, including inhibitor of nuclear factor ĸB kinase β (IKK β), c-Jun N-terminal kinase (JNK), mammalian target of rapamycin (mTOR), protein kinase C (PKC) and ribosomal S6 protein kinase (S6K), are activated by these stimulators of insulin resistance and phosphorylate insulin receptor substrate proteins on several serine residues in an uncontrollable method. There are an increasing number of data indicating that substance P, being one of the crucial activators of these kinases, is a potent cytokine that impairs insulin signaling. Here we discuss recent studies that expand our understanding of how substance P may contribute to the development of insulin resistance. In our opinion, there are many interesting data suggesting that substance P may be a new player in the pathogenesis of this unfavorable condition, leading not only to the development of diabetes mellitus type 2, but also gestational diabetes. Since the etiology of gestational diabetes remains unclear, there is a strong need to explore new directions, including those not directly associated with the canonical knowledge regarding this pathology.

Most patients with obstructive jaundice caused by an etiology other than choledocholithiasis are at risk of adenocarcinoma development. Other types of tumors are less common, although more benign. The presented study described management in case of liver hilar tumors with special regards to common hepatic duct carcinoids.