Hypoxic Conditions Modulate Chondrogenesis through the Circadian Clock: The Role of Hypoxia-Inducible Factor-1α

Hypoxia-inducible factor-1 (HIF-1) is a heterodimer transcription factor composed of an alpha and a beta subunit. HIF-1α is a master regulator of cellular response to hypoxia by activating the transcription of genes that facilitate metabolic adaptation to hypoxia. Since chondrocytes in mature articular cartilage reside in a hypoxic environment, HIF-1α plays an important role in chondrogenesis and in the physiological lifecycle of articular cartilage. Accumulating evidence suggests interactions between the HIF pathways and the circadian clock. The circadian clock is an emerging regulator in both developing and mature chondrocytes. However, how circadian rhythm is established during the early steps of cartilage formation and through what signaling pathways it promotes the healthy chondrocyte phenotype is still not entirely known. This narrative review aims to deliver a concise analysis of the existing understanding of the dynamic interplay between HIF-1α and the molecular clock in chondrocytes, in states of both health and disease, while also incorporating creative interpretations. We explore diverse hypotheses regarding the intricate interactions among these pathways and propose relevant therapeutic strategies for cartilage disorders such as osteoarthritis.

Combining biomechanical stimulation and chronobiology: a novel approach for augmented chondrogenesis?

The unique structure and composition of articular cartilage is critical for its physiological function. However, this architecture may get disrupted by degeneration or trauma. Due to the low intrinsic regeneration properties of the tissue, the healing response is generally poor. Low-grade inflammation in patients with osteoarthritis advances cartilage degradation, resulting in pain, immobility, and reduced quality of life. Generating neocartilage using advanced tissue engineering approaches may address these limitations. The biocompatible microenvironment that is suitable for cartilage regeneration may not only rely on cells and scaffolds, but also on the spatial and temporal features of biomechanics. Cell-autonomous biological clocks that generate circadian rhythms in chondrocytes are generally accepted to be indispensable for normal cartilage homeostasis. While the molecular details of the circadian clockwork are increasingly well understood at the cellular level, the mechanisms that enable clock entrainment by biomechanical signals, which are highly relevant in cartilage, are still largely unknown. This narrative review outlines the role of the biomechanical microenvironment to advance cartilage tissue engineering via entraining the molecular circadian clockwork, and highlights how application of this concept may enhance the development and successful translation of biomechanically relevant tissue engineering interventions.

The pro- and antineoplastic effects of deoxycholic acid in pancreatic adenocarcinoma cell models

BACKGROUND

Commensal bacteria secrete metabolites that reach distant cancer cells through the circulation and influence cancer behavior. Deoxycholic acid (DCA), a hormone-like metabolite, is a secondary bile acid specifically synthesized by intestinal microbes. DCA may have both pro- and antineoplastic effects in cancers.

METHODS AND RESULTS

The pancreatic adenocarcinoma cell lines, Capan-2 and BxPC-3, were treated with 0.7 µM DCA, which corresponds to the reference concentration of DCA in human serum. DCA influenced the expression of epithelial to mesenchymal transition (EMT)-related genes, significantly decreased the expression level of the mesenchymal markers, transcription factor 7- like 2 (TCF7L2), snail family transcriptional repressor 2 (SLUG), CLAUDIN-1, and increased the expression of the epithelial genes, zona occludens 1 (ZO-1) and E-CADHERIN, as shown by real-time PCR and Western blotting. Consequently, DCA reduced the invasion capacity of pancreatic adenocarcinoma cells in Boyden chamber experiments. DCA induced the protein expression of oxidative/nitrosative stress markers. Moreover, DCA reduced aldehyde dehydrogenase 1 (ALDH1) activity in an Aldefluor assay and ALDH1 protein level, suggesting that DCA reduced stemness in pancreatic adenocarcinoma. In Seahorse experiments, DCA induced all fractions of mitochondrial respiration and glycolytic flux. The ratio of mitochondrial oxidation and glycolysis did not change after DCA treatment, suggesting that cells became hypermetabolic.

CONCLUSION

DCA induced antineoplastic effects in pancreatic adenocarcinoma cells by inhibiting EMT, reducing cancer stemness, and inducing oxidative/nitrosative stress and procarcinogenic effects such as hypermetabolic bioenergetics.

Ca2+-Activated K+ Channels in Progenitor Cells of Musculoskeletal Tissues: A Narrative Review

Musculoskeletal disorders represent one of the main causes of disability worldwide, and their prevalence is predicted to increase in the coming decades. Stem cell therapy may be a promising option for the treatment of some of the musculoskeletal diseases. Although significant progress has been made in musculoskeletal stem cell research, osteoarthritis, the most-common musculoskeletal disorder, still lacks curative treatment. To fine-tune stem-cell-based therapy, it is necessary to focus on the underlying biological mechanisms. Ion channels and the bioelectric signals they generate control the proliferation, differentiation, and migration of musculoskeletal progenitor cells. Calcium- and voltage-activated potassium (KCa) channels are key players in cell physiology in cells of the musculoskeletal system. This review article focused on the big conductance (BK) KCa channels. The regulatory function of BK channels requires interactions with diverse sets of proteins that have different functions in tissue-resident stem cells. In this narrative review article, we discuss the main ion channels of musculoskeletal stem cells, with a focus on calcium-dependent potassium channels, especially on the large conductance BK channel. We review their expression and function in progenitor cell proliferation, differentiation, and migration and highlight gaps in current knowledge on their involvement in musculoskeletal diseases.

The temporal transcriptomic signature of cartilage formation

Chondrogenesis is a multistep process, in which cartilage progenitor cells generate a tissue with distinct structural and functional properties. Although several approaches to cartilage regeneration rely on the differentiation of implanted progenitor cells, the temporal transcriptomic landscape of in vitro chondrogenesis in different models has not been reported. Using RNA sequencing, we examined differences in gene expression patterns during cartilage formation in micromass cultures of embryonic limb bud-derived progenitors. Principal component and trajectory analyses revealed a progressively different and distinct transcriptome during chondrogenesis. Differentially expressed genes (DEGs), based on pairwise comparisons of samples from consecutive days were classified into clusters and analysed. We confirmed the involvement of the top DEGs in chondrogenic differentiation using pathway analysis and identified several chondrogenesis-associated transcription factors and collagen subtypes that were not previously linked to cartilage formation. Transient gene silencing of ATOH8 or EBF1 on day 0 attenuated chondrogenesis by deregulating the expression of key osteochondrogenic marker genes in micromass cultures. These results provide detailed insight into the molecular mechanism of chondrogenesis in primary micromass cultures and present a comprehensive dataset of the temporal transcriptomic landscape of chondrogenesis, which may serve as a platform for new molecular approaches in cartilage tissue engineering.

The clusterin connectome: Emerging players in chondrocyte biology and putative exploratory biomarkers of osteoarthritis

Introduction

Clusterin is amoonlighting protein that hasmany functions. It is amultifunctional Q6 holdase chaperone glycoprotein that is present intracellularly and extracellularly in almost all bodily fluids. Clusterin is involved in lipid transport, cell differentiation, regulation of apoptosis, and clearance of cellular debris, and plays a protective role in ensuring cellular survival. However, the possible involvement of clusterin in arthritic disease remains unclear. Given the significant potential of clusterin as a biomarker of osteoarthritis (OA), a more detailed analysis of its complex network in an inflammatory environment, specifically in the context of OA, is required. Based on the molecular network of clusterin, this study aimed to identify interacting partners that could be developed into biomarker panels for OA.

Methods

The STRING database and Cytoscape were used to map and visualize the clusterin connectome. The Qiagen Ingenuity Pathway Analysis (IPA) software was used to analyze and study clusterinassociated signaling networks in OA. We also analyzed transcription factors known to modulate clusterin expression, which may be altered in OA.

Results

The top hits in the clusterin network were intracellular chaperones, aggregate-forming proteins, apoptosis regulators and complement proteins. Using a text-mining approach in Cytoscape, we identified additional interacting partners, including serum proteins, apolipoproteins, and heat shock proteins.

Discussion

Based on known interactions with proteins, we predicted potential novel components of the clusterin connectome in OA, including selenoprotein R, semaphorins, and meprins, which may be important for designing new prognostic or diagnostic biomarker panels.

Cyclic uniaxial mechanical load enhances chondrogenesis through entraining the molecular circadian clock

The biomechanical environment plays a key role in regulating cartilage formation, but the current understanding of mechanotransduction pathways in chondrogenic cells is incomplete. Among the combination of external factors that control chondrogenesis are temporal cues that are governed by the cell-autonomous circadian clock. However, mechanical stimulation has not yet directly been proven to modulate chondrogenesis via entraining the circadian clock in chondroprogenitor cells. The purpose of this study was to establish whether mechanical stimuli entrain the core clock in chondrogenic cells, and whether augmented chondrogenesis caused by mechanical loading was at least partially mediated by the synchronised, rhythmic expression of the core circadian clock genes, chondrogenic transcription factors, and cartilage matrix constituents at both transcript and protein levels. We report here, for the first time, that cyclic uniaxial mechanical load applied for 1 h for a period of 6 days entrains the molecular clockwork in chondroprogenitor cells during chondrogenesis in limb bud-derived micromass cultures. In addition to the several core clock genes and proteins, the chondrogenic markers SOX9 and ACAN also followed a robust sinusoidal rhythmic expression pattern. These rhythmic conditions significantly enhanced cartilage matrix production and upregulated marker gene expression. The observed chondrogenesis-promoting effect of the mechanical environment was at least partially attributable to its entraining effect on the molecular clockwork, as co-application of the small molecule clock modulator longdaysin attenuated the stimulatory effects of mechanical load. This study suggests that an optimal biomechanical environment enhances tissue homoeostasis and histogenesis during chondrogenesis at least partially through entraining the molecular clockwork.

The role of bile acids in carcinogenesis

Bile acids are soluble derivatives of cholesterol produced in the liver that subsequently undergo bacterial transformation yielding a diverse array of metabolites. The bulk of bile acid synthesis takes place in the liver yielding primary bile acids; however, other tissues have also the capacity to generate bile acids (e.g. ovaries). Hepatic bile acids are then transported to bile and are subsequently released into the intestines. In the large intestine, a fraction of primary bile acids is converted to secondary bile acids by gut bacteria. The majority of the intestinal bile acids undergo reuptake and return to the liver. A small fraction of secondary and primary bile acids remains in the circulation and exert receptor-mediated and pure chemical effects (e.g. acidic bile in oesophageal cancer) on cancer cells. In this review, we assess how changes to bile acid biosynthesis, bile acid flux and local bile acid concentration modulate the behavior of different cancers. Here, we present in-depth the involvement of bile acids in oesophageal, gastric, hepatocellular, pancreatic, colorectal, breast, prostate, ovarian cancer. Previous studies often used bile acids in supraphysiological concentration, sometimes in concentrations 1000 times higher than the highest reported tissue or serum concentrations likely eliciting unspecific effects, a practice that we advocate against in this review. Furthermore, we show that, although bile acids were classically considered as pro-carcinogenic agents (e.g. oesophageal cancer), the dogma that switch, as lower concentrations of bile acids that correspond to their serum or tissue reference concentration possess anticancer activity in a subset of cancers. Differences in the response of cancers to bile acids lie in the differential expression of bile acid receptors between cancers (e.g. FXR vs. TGR5). UDCA, a bile acid that is sold as a generic medication against cholestasis or biliary surge, and its conjugates were identified with almost purely anticancer features suggesting a possibility for drug repurposing. Taken together, bile acids were considered as tumor inducers or tumor promoter molecules; nevertheless, in certain cancers, like breast cancer, bile acids in their reference concentrations may act as tumor suppressors suggesting a Janus-faced nature of bile acids in carcinogenesis.

Pituitary Adenylate Cyclase Activating Polypeptide Has Inhibitory Effects on Melanoma Cell Proliferation and Migration In Vitro

Pituitary adenylate cyclase activating polypeptide (PACAP) is an endogenous neuropeptide which is distributed throughout the body. PACAP influences development of various tissues and exerts protective function during cellular stress and in some tumour formation. No evidence is available on its role in neural crest derived melanocytes and its malignant transformation into melanoma. Expression of PACAP receptors was examined in human skin samples, melanoma lesions and in a primary melanocyte cell culture. A2058 and WM35 melanoma cell lines, representing two different stages of melanoma progression, were used to investigate the effects of PACAP. PAC1 receptor was identified in melanocytes in vivo and in vitro and in melanoma cell lines as well as in melanoma lesions. PACAP administration did not alter viability but decreased proliferation of melanoma cells. With live imaging random motility, average speed, vectorial distance and maximum distance of migration of cells were reduced upon PACAP treatment. PACAP administration did not alter viability but decreased proliferation capacity of melanoma cells. On the other hand, PACAP administration decreased the migration of melanoma cell lines towards fibronectin chemoattractant in the Boyden chamber. Furthermore, the presence of the neuropeptide inhibited the invasion capability of melanoma cell lines in Matrigel chambers. In summary, we provide evidence that PACAP receptors are expressed in melanocytes and in melanoma cells. Our results also prove that various aspects of the cellular motility were inhibited by this neuropeptide. On the basis of these results, we propose PACAP signalling as a possible target in melanoma progression.

The role of apoptosis in the complex pathogenesis of the most common obstetrics and gynaecology diseases

Purpose

We aimed to assess the etiological role of apoptotic genes Bcl-2 and Bax in the background of major obstetric and gynaecological diseases.

Methods

Placental tissue samples were collected from 101 pregnancies with intrauterine growth restriction and 104 pregnancies with premature birth with 140 controll samples from term, eutrophic newborns. In addition, gene expression assessment of the genes Bax and Bcl-2 was performed in 101 uterine leiomyoma tissue samples at our disposal with 110 control cases. Gene expression levels were assessed by PCR method.

Results

The expression of the Bcl-2 gene was decreased in placental samples with intrauterine growth restriction. Significant overexpression of the proapoptotic Bax gene was detected in samples from premature infants. Antiapoptotic Bcl-2 gene expression was found to be significantly increased in fibroid tissues.

Conclusion

Apoptosis plays a crucial role in the development of the most common OB/GYN conditions. Decrease in the placental expression of the antiapoptotic gene Bcl-2 may upset the balance of programmed cell death.

Cadaverine, a metabolite of the microbiome, reduces breast cancer aggressiveness through trace amino acid receptors

Recent studies showed that changes to the gut microbiome alters the microbiome-derived metabolome, potentially promoting carcinogenesis in organs that are distal to the gut. In this study, we assessed the relationship between breast cancer and cadaverine biosynthesis. Cadaverine treatment of Balb/c female mice (500 nmol/kg p.o. q.d.) grafted with 4T1 breast cancer cells ameliorated the disease (lower mass and infiltration of the primary tumor, fewer metastases, and lower grade tumors). Cadaverine treatment of breast cancer cell lines corresponding to its serum reference range (100–800 nM) reverted endothelial-to-mesenchymal transition, inhibited cellular movement and invasion, moreover, rendered cells less stem cell-like through reducing mitochondrial oxidation. Trace amino acid receptors (TAARs), namely, TAAR1, TAAR8 and TAAR9 were instrumental in provoking the cadaverine-evoked effects. Early stage breast cancer patients, versus control women, had reduced abundance of the CadA and LdcC genes in fecal DNA, both responsible for bacterial cadaverine production. Moreover, we found low protein expression of E. coli LdcC in the feces of stage 1 breast cancer patients. In addition, higher expression of lysine decarboxylase resulted in a prolonged survival among early-stage breast cancer patients. Taken together, cadaverine production seems to be a regulator of early breast cancer.

Spatial Characterization of Soybean Yield and Quality (Amino Acids, Oil, and Protein) for United States

Continued economic relevancy of soybean is a function of seed quality. The objectives of this study were to: (i) assess the spatial association between soybean yield and quality across major US soybean producing regions, (ii) investigate the relationship between protein, oil, and yield with amino acids (AAs) composition, and (iii) study interrelationship among essential AAs in soybean seed. Data from soybean testing programs conducted across 14 US states from 2012 to 2016 period (n = 35,101 data points) were analyzed. Results indicate that for each Mg ha-1 yield increase, protein yield increased by 0.35 Mg protein ha-1 and oil yield improved by 0.20 Mg oil ha-1. Essential AA concentrations exhibit a spatial autocorrelation and there was a negative relationship between concentration of AA, protein, and oil, with latitude. There was a positive interrelationship with different degree of strength among all AAs, and the correlation between Isoleucine and Valine was the strongest (r = 0.93) followed by the correlation among Arginine, Leucine, Lysine, and Threonine (0.71 < r < 0.88). We concluded that the variability in genotype (G) x management (M) x environment (E) across latitudes influencing yield also affected soybean quality; AA, protein, and oil content in a similar manner.

Plasma urea nitrogen in relation to pregnancy rate in dairy sheep

The aim of this field study was to investigate the relationship of plasma urea nitrogen (PUN) with the pregnancy rate in lactating Awassi × Merino ewes. One hundred and eighty-five Awassi × Merino ewes were used in the present study. Ewes were fed a diet containing 17.4% crude protein and were milked twice a day by the milking machine. The ewes were synchronized for estrus by insertion of intravaginal sponges containing 30 mg flurogestone acetate for 14 days. At the time of sponge removal each ewe was administered eCG (600 IU). All ewes were inseminated twice with fresh semen into the external os of the cervix at 48 and 56 h after sponge removal. The day of insemination was considered as Day 0 for calculating the gestational period. Blood samples were collected from each ewe at Days 0, 18 for measurement of PUN concentrations and at Day 22 after AI for measurement of pregnancy-associated glycoprotein (PAG) by radioimmunoassay (RIA). Thirty-eight ewes (20.5%) were confirmed pregnant by PAG-RIA test at Day 22 and by ultrasonography at Day 80. The mean (±S.D.) concentration of PUN in all ewes at Day 0 was 12.7±4.6 mmol/L. There were non-significant differences in the level of PUN between pregnant and non-pregnant ewes at Days 0 (12.2±4.2 mmol/L vs. 12.8±4.7 mmol/L, respectively) and 18 (9.6±2.9 mmol/L vs. 10.4±4.0 mmol/L, respectively) after AI. Mean PUN concentrations decreased significantly from Day 0 to Day 18 after AI in both pregnant and non-pregnant ewes. By using logistic regression analysis, there was no effect of PUN concentrations on the probability of pregnancy occurrence in the studied ewes (odds ratio: 0.97; 95% confidence interval: 0.9-1.05; P=0.45). In conclusion, there was no evidence of a relationship between PUN concentration and pregnancy rate for lactating Awassi × Merino ewes in the present study because of low pregnancy rate observed.

Effects of different fixatives on demonstrating epinephrine and ACTH hormones in Tetrahymena

The unicellular Tetrahymena produces, contains, and secretes many hormones characteristic of higher animals. We tested three fixatives, formaldehyde, N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDAC), and glutaraldehyde for suitability for immunocytochemical demonstration of epinephrine and adrenocorticotropic harmone (ACTH) in Tetrahymena. Using flow cytometric immunocytochemistry, staining of ACTH was highest after EDAC fixation and that of epinephrine after glutaraldehyde fixation. Using laser scanning confocal microscopy, formaldehyde fixation prevented staining. Glutaraldehyde fixation produced high autofluorescence, which obscured specific staining. After EDAC fixation, ACTH was localized in the ciliary row; however, demonstration of epinephrine was not improved. Our results show that there is no "fixative for any hormone." Different fixatives are needed to demonstrate different hormones in Tetrahymena.

Hormones in the nucleus of mast cells: confocal microscopic immunocytochemical observations

In earlier experiments, the presence of histamine and serotonin in the nucleus of mast cells was demonstrated. At present we studied the presence or absence of four hormones: adrenocorticotropine (ACTH), growth hormone (GH), triiodothyronine (T(3)), and progesterone. Cells of the (adult female) rat peritoneal fluid were fixed by EDAC and studied by laser-scanning confocal microscope, after treatment with primary antibodies and FITC-labeled secondary antibody. Strong ACTH and growth hormone fluorescence can be seen in the nucleus. ACTH fluorescence is present also in the granules. The cytoplasm of lymphocytes contains both ACTH and GH. T(3) shows very pale fluorescence, and progesterone is negative. The conclusion is that the nucleus of mast cells contains two polypeptide hormones studied. This was demonstrated by using EDAC fixation as this is a cross-linking agent and does not allow the escape of the minute amounts of hormones from the nucleus. Earlier observations on peptide hormones' nuclear presence and their importance are discussed.

Effects of sodium fluoride (NaF) on the cilia and microtubular system of Tetrahymena

The effect of the nucleophilic reagent NaF on the microtubular system of Tetrahymena was studied by using scanning electron microscopy (SEM), confocal microscopy, and flow cytometry. Treatments with 40 mM NaF significantly reduced the amount of alpha-tubulin while 80 mM treatment did not alter its quantity. One possible explanation for this alpha-tubulin overexpression is that the higher amount of alpha-tubulin enables this organism to carry out the appropriate function of the cytoskeleton under this undesirable influence of higher amounts of 80 nM NaF. However, the amount of acetylated tubulin increased in a dose-dependent manner. The cilia became fragile under the effect of 80 mM NaF. Confocal microscopy revealed that after 40 mM NaF treatment transversal microtubule bands (TMs) and longitudinal microtubule bands (LMs) as well as basal bodies (BBs) were extremely strong decorated with anti-acetylated tubulin antibody and TM-localization abnormalities were visible. In the 80 mM NaF-treated cells, the deep fiber of oral apparatus was very strongly labeled, while the TMs and LMs were less decorated with anti-acetylated tubulin antibody, and LM deformities were visible. It is supposed that post-translational tubulin modifications (e.g., acetylation) defend the microtubules against the NaF-induced injury. NaF is able to influence the activity of several enzymes and G-proteins, therefore is capable to alter the structure, metabolism, and the dynamics of microtubular system. The possible connection of signaling and cytoskeletal system in Tetrahymena is discussed.

T lymphocytes are targets for platelet- and trophoblast-derived microvesicles during pregnancy

Microvesicles (MVs) can derive from several cell types and their membranes contain cell surface elements. Their role is increasingly recognized in cell-to-cell communication, as they act as both paracrine and remote messengers, occurring in circulating form as well as in plasma. Successful pregnancy requires a series of interactions between the maternal immune system and the implanted fetus, such that the semi-allograft will not be rejected. These interactions occur at the materno-placental interface and/or at a systemic level. In the present study we identified for the first time the in vivo plasma pattern of the MVs of third-trimester, healthy pregnant women, their cellular origin, and their target cells using flow cytometry and confocal laser microscopy. We searched for the cellular target molecules of thrombocyte-derived MVs with the help of neutralizing antibodies. We examined the in vitro effects of MVs on STAT3 phosphorylation of primary lymphocytes and Jurkat cells. We found that both placental trophoblast-derived and maternal thrombocyte-derived MVs bind to circulating peripheral T lymphocytes, but not to B lymphocytes or NK cells. We were able to show that the P-selectin (CD62P)-PSGL-1 (CD162) interaction is one mechanism binding platelet-derived MVs to T cells. We were also able to demonstrate that MV-lymphocyte interactions induce STAT3 phosphorylation in T cells. Our findings indicate that both thrombocyte- and trophoblast-derived MVs may play an important role in the immunomodulation of pregnancy. We suggest that the transfer of different signals via MVs represents a novel form of communication between the placenta and the maternal immune system, and that MVs contribute to the establishment of stable immune tolerance to the semi-allograft fetus.

Effect of femtomolar concentrations of hormones on insulin binding by Tetrahymena, as a function of time

The unicellular ciliate Tetrahymena, contains and binds hormones, characteristic of vertebrates. Earlier experiments demonstrated the effect of extremely low concentrations of hormones. In the present experiments, the effect of various hormones (endorphin, serotonin, histamine, insulin and epidermal growth factor [EGF]) in 10(-15) M, or oxytocin, gonadotropin at 0.001 IU concentrations) on the binding of FITC-insulin was studied by using flow cytometry and confocal microscopy, after 1, 5, 15, 30 and 60 min. Six of the seven hormones promptly decreased the cells' hormone binding capacity, the exception being EGF, and in four cases (endorphin, serotonin, insulin and oxytocin) the reduction was enormous. The decreased binding was durable. However, in the case of endorphin and oxytocin after 30 min, and in the case of serotonin after 60 min the binding returned to the control level. In the case of oxytocin after 60 min, binding significantly surpassed the control level. Histamine returned to the control level after 15 min, but after that the binding became even lower. EGF provoked special behaviour: it increased hormone binding after 30 and 60 min. The results call attention to the extreme sensitivity of Tetrahymena receptors to hormonal inductions and to its quick response ability.

Preservation of fertility in reproductive-age women with the diagnosis of cancer

Over the past few decades the number of young, reproductive age cancer survivors has increased as a result of improved and less destructive cancer treatments. Certain types of cancers are predominantly diagnosed among reproductive age women and a small proportion of cancers originating in the reproductive tract are also detected in this age group. Treatment in the past used to be definitive and in most cases led to sterility. In recent years, improved medical treatments and more conservative surgical approaches have been introduced increasing the number of young survivors of cancer treatment. These less invasive treatments seem to be associated with similar survival rates and fertility can be preserved in most cases. This has led to studies evaluating the reproductive options of these women. Conservative surgical techniques, the use of chemotherapeutic agents with a reduced gonadotoxic side-effect profile, and the application of more focused radiation therapy are associated with maintenance of fertility. In addition, assisted reproductive technology (ART) has undergone tremendous improvements and now offers several alternatives to those who wish to maintain fertility before or even after cancer therapy. This review summarizes the fertility sparing medical and surgical as well as ART options that reproductive age women desiring to maintain fertility may utilize if they face cancer therapy.

Effect of histone deacetylase inhibitor trichostatin A (TSA) on the microtubular system of Tetrahymena

Histone deacetylases can also influence acetylation of tubulin. In the present experiments, after 60 min of 10 microM trichostatin (TSA) treatment the structure and amount of tubulin and acetylated-tubulin were studied immunocytochemically, by using confocal microscopy and flow cytometry. In TSA-treated Tetrahymena cells deep fibres were never labeled with antibody to acetylated tubulin. Flow cytometry with anti acetylated-tubulin antibody demonstrated that in the contol cell populations there were weaker and stronger labelled parts. After TSA treatment in the weaker labeled part the cell number decreased, and in the stronger labeled part increased significantly: this means that after the histone deacetylase inhibitor TSA treatment the amount of acetylated-tubulin in numerous Tetrahymena cells is significantly elevated. Labeling with anti-tubulin antibody was not changed significantly. On the basis of these results we postulate that histone deacetylase also in Tetrahymena influences the acetylation of tubulin, and this enzyme is sensitive to TSA treatments.

Effects of taxol treatment on the microtubular system and mitochondria of Tetrahymena

Complex investigation was done using immunocytochemical confocal microscopy, electron microscopy and flow cytometry on the effect of taxol to the microtubular arrangement and dynamics. The most interesting phenomenon was the rapid disappearance of transversal microtubule bands, while longitudinal microtubule bands remained and were submitted to the known effects of taxol. There was a broad variation in mitochondrial effect, some of them remained normal, while others swollen, desintegrated and their tubules disoriented. Treatment with 50 nM taxol significantly reduced the binding of anti alpha-tubulin antibody and a lesser degree anti-acetylated tubulin antibody. The difference between the transversal and longitudinal microtubules is emphasized by the results and the paper discusses the possibilities of indirect effects of taxol to the transversal microtubules (tubulin-GTP interaction, faster turnover, mitochondrial interaction). Polyglutamylation of tubulin has not a role in this difference.

Transgenerational effect of neonatal vitamin A or D treatment (hormonal imprinting) on the hormone content of rat immune cells

Male offspring of neonatally vitamin A or D treated (hormonally imprinted) rat dams were studied for hormone (adrenocorticotrophine [ACTH], beta-endorphin, histamine, triiodothyronine [T3]) content in immune cells, by using immunocytochemical methods for flow cytometry and confocal microscopy. ACTH and T3 were almost doubled in the lymphocytes of vitamin A treated mothers' offspring, while histamine decreased to a one-third in the histamine content of vitamin D treated mothers' offspring. Part of the animals received vitamin treatment again 24 hours before measurement, however, only endorphin content elevated moderately. In the offspring of untreated dams administered with vitamin D 24 hours before measurement, each cell type studied (lymphocyte, monocyte-granulocyte group, mast cell) had a one-third lower T3 content, which shows that vitamin D treatment can influence hormone content of immune cells. The experiments call attention to the transgenerational effect of perinatal treatment with lipid-soluble, intracellular receptor-bound vitamins.

In vitro effect of biogenic amines on the hormone content of immune cells of the peritoneal fluid and thymus. Is there a hormonal network inside the immune system?

Immune cells contain different hormones and hormone-like molecules, such as insulin, endorphin, triiodothyronine (T3) histamine, serotonin. In earlier in vitro experiments insulin down-regulated histamine, serotonin and T3 content of thymus cells. Now we studied the effect of biogenic amines on the endorphin, T3, serotonin and histamine content of rat peritoneal and thymic cells. Cells were obtained from male rats of 100g body weight. 100 ng/ml serotonin or 300 ng/ml histamine was added for 30 min. After that the cells were prepared for flow cytometric analysis with antibodies to endorphin, T3, histamine and serotonin as primary antibodies and anti-rabbit IgG as secondary antibody. Finishing the measurements the cells were also studied by confocal microscopy. T3 concentration (binding of anti-T3 antibody) increased in peritoneal mast cells after serotonin treatment and in the monocyte-macrophage-granulocyte group after histamine treatment. Thymocytes' T3 content radically decreased after both treatments. Serotonin and histamine treatment also radically reduced the amine content of each other. Endorphin level was resistant to hormonal treatments. The results call attention to a possible hormonal network inside the immune system in which hormones produced by the immune cells themselves can influence each other.

Increased hormone levels in Tetrahymena after long-lasting starvation

Tetrahymena contains vertebrate hormone-like materials. The level of one of these, insulin increased during starvation in a previous experiment. We hypothesized that other hormones are also influenced by starvation. To prove the hypothesis Tetrahymena pyriformis cultures were (1) starved for 24h; (2) starved for 24h and re-fed for 30min or (3) starved for 30min. Amount and localization of vertebrate-like hormones, produced by Tetrahymena, beta-endorphin, adrenocorticotropin (ACTH), serotonin, histamine, insulin and triiodothyronine (T(3)) were studied by immunocytochemical methods using flow cytometry and confocal microscopy. Long starvation elevated with 50% the hormone levels, while short starvation moderately elevated only the serotonin level in the cells. After short re-feeding endorphin and histamine returned to the basal level, ACTH and serotonin approached the basal level, however, remained significantly higher, while insulin and T(3) stood at the starvation level. The results show that such a stress as long starvation provokes the enhanced production of hormones which likely needed for tolerating the life-threatening effect of stress.

Serotonin content is elevated in the immune cells of histidine decarboxylase gene knock-out (HDCKO) mice. Focus on mast cells

OBJECTIVE

Biogenic amines, histamine and serotonin are present in the granules and nucleus of mast cells. We wanted to study the presence, amount and localization of serotonin in mast cells and other cells of the immune system, under conditions of histamine deficiency caused by knock out of histamine decarboxylase gene (HDCKO).

METHODS

Wild type and histamine deficient HDCKO mice were studied for serotonin content of the immune cells (lymphocytes as well as the monocyte-granulocyte-mast cell group) using flow cytometry and confocal microscopy. Groups of mice were kept either on complete rodent chow or on a histamine-free diet for a month before the experiments.

RESULTS

The amount of serotonin was significantly higher in the KO animals, irrespective of the diet. Confocal microscopy demonstrated the presence of serotonin in the nucleus of mast cells in the wild type animals, while it was not present in the KO mice. Furthermore, in the cytoplasm (granules) of KO mast cells a bright fluorescence was observed in contrast to the pale fluorescence of wild animals.

CONCLUSION

It seems likely that serotonin replaces the deficient histamine in the heparin-biogenic amine complex in the mast cell granules.

Comparison of the insulin binding, uptake and endogeneous insulin content in long- and short-term starvation inTetrahymena

FITC-insulin binding and endogenous insulin content of Tetrahymena pyriformis, that had been 24 h or 30 min starved, continuously fed or re-fed after starvation was studied by flow cytometry and confocal microscopy. Long starvation elevated both insulin binding and endogenous insulin content of the cells. Short re-feeding after long starvation or short starvation after continuous feeding does not change the situation. Fixed cells also bind FITC-insulin, however, in this case long starvation reduces, and re-feeding after long starvation elevates, the binding, which means that hormone binding by receptors only differs from receptor binding and engulfment (in living cells). The increase of FITC-insulin content in living cells seems to be due to engulfment, rather than by receptor binding. The results point to the unicellular organism's requirement for insulin production and binding in a life-threatening stress situation.

Effect of starvation on insulin production and insulin binding in Tetrahymena

Tetrahymena pyriformis GL was starved for 24 h and then the immunologically demonstrable insulin content and FITC-insulin binding were measured by flow cytometry and localization was studied by confocal microscopy. The amount of endogeneous insulin as well as FITC insulin binding, was highly significantly elevated. Glucose feeding for 30 min abolished the elevation of FITC-insulin binding. In starved cells, insulin-binding sites disappeared from the surface and FITC-insulin was bound inside the cells, within large food vacuoles. Endogeneous insulin was dispersed in the cytoplasm both in the control and starved cells and food vacuoles did not contain it. The results call attention to the stimulatory effect of starvation on insulin production in Tetrahymena, in parallel with the internal storage of insulin receptors, which points to an autocrine mechanism.

Effects of extremely low concentrations of hormones on the insulin binding of Tetrahymena

FITC-insulin binding to previously hormone-treated Tetrahymena was studied by flow cytometry and confocal microscopy. Hormones produced by Tetrahymena were chosen for study and the hormone concentrations were administered between 10(-6) and 10(-21)M for 30 min. Endorphin, serotonin and insulin significantly reduced the hormone binding however histamine did not influence it at all. Endorphin, serotonin and insulin were significantly effective down to 10(-18)M and the effect of insulin and endorphin suggest a similar mechanism. The results call attention to the efficacy of very low hormone concentrations, which can influence the hormone content (earlier experiments) and receptor binding capacity (present study) of a unicellular organism. This seems to be very important, as in wild (natural) conditions the dilution of signaling materials secreted by a water-living protozoan is very high. In addition, the results point to the selectivity of response, as not all of the hormones that deeply influence other physiological indices (e.g. histamine) have an effect on insulin content or insulin receptors.

How does the unicellular Tetrahymena utilise the hormones that it produces? Paying a visit to the realm of atto-and zeptomolar concentrations

Changes in the hormone content of Tetrahymena pyriformis GL were investigated during histamine, serotonin or insulin treatment at concentrations of 10(-6)M to 10(-21)M for 30 min. The immunologically demonstrable hormone content was studied by using specific antibodies, flow cytometry and confocal microscopy. Histamine at the higher ranges elevated the serotonin content of Tetrahymena, whereas serotonin at the lower ranges (down to 10(-21)M) decreased its histamine levels. Insulin did not affect its serotonin content, whereas serotonin increased its insulin content at each concentration studied (down to 10(-21)M). Insulin between 10(-6)M and 10(-21)M increased the histamine levels of Tetrahymena, although histamine influenced its insulin level only at 10(-6)M. Our results call attention to the presence of hormonal interactions even at "low" levels of phylogeny and to the extreme sensitivity of the hormone receptors of Tetrahymena. These data might explain (1) the requirement of Tetrahymena for (vertebrate) hormone production and hormone receptors and (2) the way that it uses these hormones under natural conditions.

Comparison of the binding of anti-tubulin antibody and the fluorescent taxol derivative Flutax-1 to the microtubular system of Tetrahymena

Using confocal microscopic analysis, FITC-labelled anti-alpha-tubulin antibody and the fluorescent taxol derivative Flutax-1 in fixed and living Tetrahymena pyriformis GL, longitudinal microtubules, oral and somatic cilia, deep fibers, and contractile vacuole pores were equally labeled. While the antibody stained transversal microtubules, these were not labeled by Flutax-1. At the same time, oral cilia were more intensely stained by Flutax-1, than by the antibody. There were no differences in the staining of fixed preparations and living cells. The observations suggest (i) the difference between the MAPs of longitudinal and transversal microtubules which allow or inhibit the binding of the indicator molecules, and (ii) the different functions of these two types of microtubules.

Influence of paraformaldehyde and EDAC fixation on the demonstrability of hormones (histamine, endorphin, triiodothyronine) in rat immune cells: An immunocytochemical comparative analysis

The amount and localization of three hormones (histamine, endorphin and triiodothyronine [T(3)]) was measured in male and female rat peritoneal cells (lymphocytes, mast cells, monocyte-macrophage-granulocyte group [mo-gran]) using flow cytometry as well as confocal microscopy after paraformaldehyde (PFA) or EDAC fixation. In the EDAC fixed lymphocytes and mo-gran of female animals two-magnitude higher levels of histamine were measured after EDAC fixation and one magitude higher in mast cells. The amount of T(3) was almost four-fold in lymphocytes and 2.5-4-fold in mast cells and mo-gran. Endorphin content was not altered by the type of fixation. In each cell type in males one magnitude higher levels of histamine and T(3) were measured after EDAC fixation and a small, but significant, elevation of endorphin. Confocal microscopy supports the quantitative data. The results show that (1) the fixation with the crosslinking molecule, EDAC, is more suitable for immunocytochemical studies of amino-acid type hormones in immune cells, (2) more histamine and T(3) are present in the immune cells than it was supposed previously when studying PFA-fixed preparations, (3) the estimation of the amount of peptide hormones seems to be accurate after PFA fixation, (4) there is a quantitative difference comparing the results of PFA and EDAC fixation between males and females.

EDAC fixation increases the demonstrability of biogenic amines in the unicellular Tetrahymena: A flow cytometric and confocal microscopic comparative analysis

Earlier experiments demonstrated the presence of hormones of the higher ranked animals in Tetrahymena. In the present experiments two fixatives, paraformaldehyde, which is commonly used and a carbodiimide, EDAC that was recommended by Panula et al. for the immunocytochemistry of histamine, are compared in Tetrahymena for the demonstration of histamine and serotonin by using flow cytometry and confocal microscopy. Both hormone levels were significantly higher after EDAC fixation; serotonin almost doubled and histamine was more than fivefold. The confocal microscopic pictures were clearer and the hormones' localization was easier. The results support earlier observations on the presence of these hormones in Tetrahymena and points to the advantage of EDAC fixation for demonstrating these hormones immunocytochemically.

Influence of in vitro and in vivo insulin treatment on the hormone (histamine, serotonin, endorphin and triiodothyronine) content of thymus and spleen cells

Thymic and spleen cells were treated in vitro or in vivo with insulin. The in vitro treatments were done with 10(-6), 10(-9), 10(-12) and 10(-15) M concentrations for 30 min and after that histamine, serotonin, endorphin and triiodothyronine (T3) content of the cells were detected by using antibodies to the hormones and flow cytometry as well as confocal microscopy. For in vivo treatment 1 IU/kg insulin was given for adult rats and 1 h after that the target hormone contents were determined by the same manner. Histamine and T3 content radically decreased in the thymus after in vitro treatment independent on the insulin concentrations administered. In vivo treatment halved histamine and T3 content. Serotonin content also decreased after in vitro treatment with the two higher concentrations, however the in vivo treatment did not cause a change. Histamine content was elevated after in vitro treatment in the spleen, independent on the insulin concentration. Endorphin level was not influenced at all. The experiments demonstrate that insulin is a factor which regulates the content (production, storage, secretion?) of some immunologically important molecules of the immune cells. Since each hormone molecule studied has important immunomodulatory role, the experiment points to the indirect immunomodulatory role of insulin.

Influence of the N-acetylation polymorphism on the metabolism of talampanel: an investigation in fasted and fed subjects genotyped for NAT2 variants

Talampanel is a 2,3-benzodiazepine-type allosteric (noncompetitive) AMPA-antagonist currently being developed as an orally active, broad-spectrum anticonvulsant. Here, a detailed study of its N-acetylation in humans is presented using plasma concentration data of both TLP and its N-acetyl metabolite obtained from healthy volunteers (n = 28) genotyped for N-acetyltansferase NAT2 isozymes. Plasma samples were obtained for up to 48 h after a single oral dose of 75 mg TLP both in fasted and in fed subjects. A perfect correspondence could be established between the phenotype inferred before the study from genotyping and that determined after the study by using plasma metabolite-to-parent molar ratios confirming that this route of metabolism is indeed mediated by NAT2. Analysis of the data has been performed using both noncompartmental analysis and a custom-built, unified parent-metabolite PK model, which incorporates three different acetylation rates according to the genotype-based classification of each subject as slow, intermediate, or fast acetylator to simultaneously fit plasma levels for both TLP and its metabolite. This suggest that for TLP in humans, (i) N-acetylation represents only a relatively small fraction of its total elimination (about one-fourth in fast acetylators and much less in slow acetylators), (ii) acetylation is about eight-twelve times faster in fast and three-six times faster in intermediate acetylators than in slow acetylators, and (iii) the N-acetyl metabolite is eliminated faster than the parent TLP.

Alcohol consumption during gestation reduces the histamine and triiodothyronine content of rat immune cells

OBJECTIVE

Different factors acting during pregnancy can cause non-morphological alterations of cells which are manifested later, in adulthood. We studied the effect of maternal alcohol consumption for one day in early pregnancy on the hormone content of immune cells in the adult rat.

METHODS

Lactating dams were given 15% ethanol in the drinking water for 24 h on the 3rd day post partum, exposing their pups to ethanol in the breast milk. Some of the same dams had been successfully mated on the day of delivery, so that they were also 3 days pregnant on the treatment day, exposing embryos to alcohol on the third day of pregnancy. In 4 month old pups histamine and triiodothyronine (T(3)) content of citrate elicited peritoneal immune cells (lymphocytes, monocyte-macrophage-granulocyte group, mast cells) as well as thymic cells were determined by flow cytometry and confocal microscopy using specific antibodies.

RESULTS

Alcohol treatment during pregnancy decreased highly significantly the content of both hormones in peritoneal cells of the 4 month old adult animals while it was ineffective by breast feeding after birth. Thymic cells did not show any changes.

CONCLUSION

Since the immune system had not developed at the time of treatment (3rd day of pregnancy), stem cells were presumably imprinted. Our results indicate the deleterious effects of early maternal alcohol consumption on the hormone content of the immune system.

Effect of drugs affecting microtubular assembly on microtubules, phospholipid synthesis and physiological indices (signalling, growth, motility and phagocytosis) inTetrahymena pyriformis

Structural changes of microtubules, incorporation of radioactively labelled components into phospholipids, cell motility, growth and phagocytosis were studied under the effect of four drugs affecting microtubular assembly: colchicine, nocodazole, vinblastine and taxol. Although the first three agents influence microtubules in the direction of depolymerization and the fourth stabilizes them, their effects on the structure of microtubules cannot be explained by this. Using confocal microscopy after an acetylated anti-tubulin label, in nocodazole- and colchicine-treated cells, the basal body cages disappear and longitudinal microtubules (LM) became thinner without changing transversal microtubules (TM). After taxol treatment LM also became thinner, however TM disappeared. Under the effect of vinblastine TM became thinner, without influencing LM. These drugs influence the incorporation of components ([(3)H]-serine, [(3)H]-palmitic acid and (32)P) into phospholipids, however their effect is equivocal and cannot be consequently coupled with the effect on the microtubules. Nocodazole, vinblastine and taxol significantly reduced the cell's motility, however colchicine did so to a lesser degree. Vinblastine and nocodazole totally inhibited, and taxol significantly decreased cell growth, while colchicine in a lower concentration increased the multiplication of cells. Phagocytosis was not significantly influenced after 1 min, but after 5 min all the agents studied (except colchicine) significantly inhibited phagocytosis. After 15 and 30 min each molecule caused highly significant inhibition. The experiments demonstrate that drugs affecting microtubular assembly dynamics influence differently the diverse (longitudinal, transversal etc.) microtubular systems of Tetrahymena and also differently influence microtubule-dependent physiological processes. The latter are more dependent on microtubular dynamics than are changes in phospholipid signalling.

Prolonged effect of stress (water and food deprivation) at weaning or in adult age on the triiodothyronine and histamine content of immune cells

We used two days of total water and food deprivation as stress for female rats at weaning (three weeks old) and at adult age (two and a half months old). Triiodothyronine (T3) and histamine content of immune cells (lymphocytes, mast cells and monocyte-macrophage-granulocyte group in peritoneal fluid; lymphocytes, granulocytes and monocytes in blood; and lymphocytes in thymus) were studied three weeks after stress application using specific antibodies for flow cytometry and confocal microscopy. The stress at weaning increased T3 content of thymus lymphocytes. In case of adult T3, there was a cell type independent significant effect of stress, decreasing values in peritoneal fluid and slightly increasing effect in the blood. Histamine content of granulocytes was also significantly elevated. The experiments demonstrate that not only fetal or neonatal stress has long-lasting consequences, but also stress events in later periods of life in cells (organs) that are continuously differentiating. We will go on to discuss the importance of T3 and histamine in connection with stress and immunity.

Presence of hormones (triiodothyronine, serotonin and histamine) in the immune cells of newborn rats

Five hormones in lymphatic cells from the spleen and thymus of newborn rats were measured using flow cytometry and confocal microscopic immunofluorescence. Immunoreactive histamine, serotonin and triiodothyronine (T(3)) were present in the cells. However, growth hormone and insulin were not observed, except for low levels of insulin in a few spleen cells. Serotonin content was modest compared to the histamine and T(3) levels. The localization of each hormone in the cells was different. The importance of these observations in the light of functional data is discussed.