Browsing by Author "Cirovic, Sanja (36027425000)"

Introduction: Pituitary neuroendocrine tumours (PitNETs), traditionally designated as pituitary adenomas, show relatively frequent invasive growth with exceptional metastatic potential, the causes of which are not entirely elucidated. Kisspeptins, which perform their activity through KISS1 receptor (KISS1R), are recognised as metastatic suppressors in many malignant tumours. This study aimed to investigate the immunohistochemical expression of kisspeptin and KISS1R in different types of PitNETs and to compare it with the expression in the normal anterior pituitary, using tissue microarray. Material and methods: The experimental group consisted of 101 patients with PitNETs, with 45 (37.3%) being of gonadotroph, 40 (33.9%) somatotroph, 4 (3.4%) corticotroph, 4 (3.4%) thyrotroph, 3 (2.5%) lactotroph, and 6 (5.1%) null-cell type. The control group consisted of anterior pituitary tissue accidentally removed during the surgery for PitNETs in 17 patients. Results: Kisspeptin expression was observed in both experimental and control groups, without statistically significant differences in the staining intensity. Negative kisspeptin staining was detected in 10 (9.9%), weak in 79 (78.2%), and moderate in 12 tumours (11.9%); none of the tumours had strong staining intensity. The weak staining intensity was predominant in all PitNET types except thyrotroph tumours. Significant statistical difference in terms of kisspeptin expression between types of PitNET and the control group was not observed. Immunohistochemical expression of KISS1R was not observed in the control group or in the experimental group. Conclusions: We conclude that immunohistochemistry, as a method, cannot confirm the involvement of kisspeptin in tumourigenesis and aggressiveness of PitNETs, but potentially supports its antimetastatic role. The absence of KISS1R immunohistochemical expression in all anterior pituitaries and PitNETs in our cohort needs verification through the use of different procedures designed for the detection of the presence and localisation of proteins in the cell. (Endokrynol Pol 2021; 72 (2): 91-96). © 2021 Via Medica. All rights reserved.

Introduction: Pituitary neuroendocrine tumours (PitNETs), traditionally designated as pituitary adenomas, show relatively frequent invasive growth with exceptional metastatic potential, the causes of which are not entirely elucidated. Kisspeptins, which perform their activity through KISS1 receptor (KISS1R), are recognised as metastatic suppressors in many malignant tumours. This study aimed to investigate the immunohistochemical expression of kisspeptin and KISS1R in different types of PitNETs and to compare it with the expression in the normal anterior pituitary, using tissue microarray. Material and methods: The experimental group consisted of 101 patients with PitNETs, with 45 (37.3%) being of gonadotroph, 40 (33.9%) somatotroph, 4 (3.4%) corticotroph, 4 (3.4%) thyrotroph, 3 (2.5%) lactotroph, and 6 (5.1%) null-cell type. The control group consisted of anterior pituitary tissue accidentally removed during the surgery for PitNETs in 17 patients. Results: Kisspeptin expression was observed in both experimental and control groups, without statistically significant differences in the staining intensity. Negative kisspeptin staining was detected in 10 (9.9%), weak in 79 (78.2%), and moderate in 12 tumours (11.9%); none of the tumours had strong staining intensity. The weak staining intensity was predominant in all PitNET types except thyrotroph tumours. Significant statistical difference in terms of kisspeptin expression between types of PitNET and the control group was not observed. Immunohistochemical expression of KISS1R was not observed in the control group or in the experimental group. Conclusions: We conclude that immunohistochemistry, as a method, cannot confirm the involvement of kisspeptin in tumourigenesis and aggressiveness of PitNETs, but potentially supports its antimetastatic role. The absence of KISS1R immunohistochemical expression in all anterior pituitaries and PitNETs in our cohort needs verification through the use of different procedures designed for the detection of the presence and localisation of proteins in the cell. (Endokrynol Pol 2021; 72 (2): 91-96). © 2021 Via Medica. All rights reserved.

The effect of resveratrol on vasculature of diabetic animal is not defined. This study was aimed at evaluating how alloxan-induced diabetes alters the relaxation of the isolated rat renal artery (RA) to resveratrol and determining whether prolong hyperglycemia modifies the expression of potassium (K) channels in the wall of RA. Diabetes reduced the sensitivity to resveratrol in RA. According to K channel blocker affinity, it seems that different subtype of K channels were involved in the resveratrol-induced relaxation of RA of normal rats and only voltage-sensitive Kv1 channels took part in the resveratrol effect on the RA of diabetic rats. Endothelial dysfunction developed during diabetes led to down-regulation of the expression of almost all tested K channels, while up-regulation of Kv1.3 channel expression was only noticeable. Having in mind that Kv1.3 channels have a prominent role in insulin signalling, these results suggest renovascular protective effect of resveratrol in diabetes. © 2018 Elsevier Ltd

The effect of resveratrol on vasculature of diabetic animal is not defined. This study was aimed at evaluating how alloxan-induced diabetes alters the relaxation of the isolated rat renal artery (RA) to resveratrol and determining whether prolong hyperglycemia modifies the expression of potassium (K) channels in the wall of RA. Diabetes reduced the sensitivity to resveratrol in RA. According to K channel blocker affinity, it seems that different subtype of K channels were involved in the resveratrol-induced relaxation of RA of normal rats and only voltage-sensitive Kv1 channels took part in the resveratrol effect on the RA of diabetic rats. Endothelial dysfunction developed during diabetes led to down-regulation of the expression of almost all tested K channels, while up-regulation of Kv1.3 channel expression was only noticeable. Having in mind that Kv1.3 channels have a prominent role in insulin signalling, these results suggest renovascular protective effect of resveratrol in diabetes. © 2018 Elsevier Ltd