Background: Uterine leiomyoma is the most widespread benign tumor affecting women of childbearing age. There are still gaps in the understanding of its pathogenesis. Telocytes are unique cells found in more than 50 different locations inside the human body. The functional relationship between cells could clarify the pathogenesis of leiomyomata. Examination of membrane receptors on telocytes could explain their role in fibrosis, oxidative stress, and myometrial contractility.

Aim: This research was conducted to assess the density of telocytes in terms of their putative role in leiomyoma formation by focusing on their correlation with the expression of estrogen and progesterone receptors.

Methods: For gross evaluation of uterine tissue samples from leiomyoma, routine histology of adjacent and unaffected myometrium was performed. Immunohistochemical analysis of c-kit, tryptase, CD34, PDGFRα (telocyte-specific), and ER and PRs (estrogen and progesterone receptors) was performed to examine uterine telocytes and the expression of sex steroid receptors.

Results: The decline in telocyte density in leiomyoma foci was correlated with high progesterone expression and low estrogen receptor expression. The unchanged myometrium showed the opposite correlation and balance between both steroid hormone receptors. The difference in sex steroid receptor expression is correlated with the density of uterine telocytes, which emphasizes their conductor function.

Conclusions: A reduction in telocyte density and the changes in examined marker expression demon-strate the involvement of telocytes in local homeostasis. The expression of membrane receptors explicitly indicates their functional potential in the human myometrium, focusing attention on contractility and local homeostasis.

Knowledge of uterine fibroids has existed since the time of Hippocrates. However, there are still wide gaps in the understanding of its pathogenesis. No single theory explains the background of uterine fibroid pathology, which affects more than 50% of women worldwide. By contrast, a newly depicted cell type called telocytes was only recently identified in the past twenty years. Th ese cells have evoked ambivalent opinions in the scientific community. The unique features of telocytes coupled with experimental evidence by numerous researchers and our hypotheses and conceptions are discussed in this review. We emphasize the main telocyte interactions in the context of the uterine fibroid architecture. This review reveals the pivotal role of telocytes, describing their contacts with smooth muscle cells, fibroblasts, vessels and nerves, inflammatory cells and stem cells. Our data are based on the latest publications and our own results.

I n t r o d u c t i o n: Hydronephrosis is an actual pediatric problem, affecting children in the anteand neonatal periods. Intrinsic stenosis is due to external obstruction and creates a pathophysiological basis of this urological pathology. Co-localization of ureter with a renal vasculature also could not be omitted from this point of view. Mesenchymal cells, partially telocytes, are important for local fibrosis development and hydronephrosis formation as well. In the current study, we focused on identification of telocytes in the human ureters to hypothesize their role in hydronephrosis pathophysiology.

M a t e r i a l a n d Me t h o d s: The samples were taken from 18 surgically treated patients with hydronephrosis (due to ureteral obstruction and crossing renal vessel). The control group consisted of 10 patients suffered from a non-obstructive disease of the urinary tract — predominantly renal tumors. Tissue samples from a ureter were stained for c-kit, tryptase, CD34 and PDGFRα to identify telocytes. Routine histology was performed to analyze tissue morphology, collagen deposits and mast cell’s profile.

R e s u l t s: Telocytes were detected in the ureteral wall. In patients with hydronephrosis we revealed decreasing density of telocytes, the prevalence of collagen, rise in mast cells amount and the ureteral wall thickening. In ureters with crossing renal vessels as a primary etiologic factor more telocytes have been observed in comparison with the obstructive hydronephrosis.

C o n c l u s i o n s: A declined density of telocytes accompanied hydronephrosis development. Increased number of mast cells in the ureteral wall reflects a local inflammation, while detailed observation of collagen/muscle deposits and density of telocytes reveal a difference depended on etiologic factor (obstruction or crossing vessel) in patients with hydronephrosis.

Introduction: Uterine leiomyoma is the most widespread benign tumor affecting women of childbearing age. There are still gaps in the understanding of its pathogenesiss. Telocytes are unique cells described in greater than 50 different locations inside the human body. The functional relationship of cells could clarify the pathogenesis of leiomyomata. In the current study, we focused on the identification of telocytes in all regions of the human uterus to explain their involvement in leiomyoma development.

Materials and Methods: Tissue samples from a healthy and myomatous uterus were stained for c-kit, tryptase, CD34 and PDGFRα to identify telocytes. Routine histology was performed to analyze tissue morphology and collagen deposits.

Results: Telocytes were detected in the cervix, corpus of the uterus and leiomyoma. The density of telocytes in fibroid foci was reduced compared with normal myometrium.

Conclusions: Our results demonstrated the existence of telocytes in all parts of the human body affected and unaff ected by leiomyoma of the uterus. In addition, telocytes were also present in leiomyoma foci. Our results suggest that the reduced density of telocytes is important for the pathomechanisms of myometrial growth, demonstrating its value as a main component of the myomatous architecture.

Background: Anorexia nervosa is a widely prevalent eating disorder that often leads to life-threatening complications. Since it mostly concerns females, many authors have focused on studying the reproductive system in anorexic women. Recently discovered telocytes may give a new insight into the pathophysiology of gynecological complications in these patients.

Material and Methods: We adopted an animal model of anorexia nervosa induced by voluntary physical activity. Sixteen female Wistar rats were divided into two groups: control and activity-based anorexia. When the weight loss of activity-based anorexia (ABA) rats reached 25% animals were euthanized. Size and weight measurements as well as histopathological analysis of the reproductive organs were performed. Additionally, we used immunohistochemical staining for detection of telocytes.

Results: Telocytes were identified in uteri of anorectic rats but no diff erences were observed when compared to the control group. Nevertheless, in the ABA group the weight of the uteri and the number of follicles in the ovaries decreased significantly.

Conclusions: Our rat model of anorexia nervosa mimics the effects of this eating disorder that occur in the female reproductive system since we reported ovarian dysfunction and uterine involution in the experimental animals. It supports its potential role in the further studies of anorexia pathophysiology and treatment possibilities.

Telocyte (TC) is an interstitial cell type with a small cellular body and extremely long tentacle-like extensions. TCs were discovered a decade ago and have specific morphological characteristics, immunohistochemical and secretome profi les, electrophysiological properties, microRNA expression. Moreover, they are different in gene expression from other cells. TCs play an important role in plenty of processes. Apparently, they are involved in homeostasis, remodelling, regeneration, repair, embryogenesis, angiogenesis and even tumorigenesis. “Telocytes need the world”, was emphasized by Professor Popescu and it will be actual at any time. This review summarizes particular features of TCs in different organs and systems, emphasizing their involvement in physiological and pathophysiological processes.