Radiation of bilateral adrenal metastases is associated with a high risk of primary adrenal insufficiency

BACKGROUND

Adrenal metastasis is the most common adrenal malignancy and can be bilateral in up to 43% of patients. Radiotherapy (RT) is one option available to treat adrenal metastases. The risk of primary adrenal insufficiency (PAI) after adrenal RT is unclear.

OBJECTIVE

Determine the incidence and the timeline of PAI in patients undergoing adrenal RT.

DESIGN, SETTING AND PARTICIPANTS

Single-centre longitudinal retrospective cohort study of adult patients with adrenal metastases treated with RT between 2010 and 2021.

RESULTS

Of 56 patients with adrenal metastases treated with adrenal RT, eight (14.3%) patients developed PAI at a median of 6.1 months (interquartile range [IQR]: 3.9-13.8) after RT All patients developing PAI had either unilateral RT in the setting of contralateral adrenalectomy or bilateral adrenal RT. Patients who developed PAI received a median RT dose of 50 Gy (IQR: 44-50 Gy), administered in a median of five fractions (IQR: 5-6). Treated metastases decreased in size and/or metabolic activity on positron emission tomography in seven patients (87.5%). Patients were initiated on hydrocortisone (median daily dose of 20 mg, IQR: 18-40) and fludrocortisone (median daily dose of 0.05 mg, IQR: 0.05-0.05 mg). At the end of the study period, five patients died, all due to extra-adrenal malignancy, at a median time of 19.7 months (IQR: 16-21.1 months) since RT and median time of 7.7 months (IQR: 2.9-12.5 months) since the diagnosis of PAI.

CONCLUSION

Patients receiving unilateral adrenal RT with two intact adrenal glands have a low risk of PAI. Patients receiving bilateral adrenal RT have a high risk of PAI and require close monitoring.

[PHYTOCORRECTION OF IMMUNOLOGICAL AND BIOCHEMICAL CHANGES IN THE COMBINED IMPACT OF COAL DUST AND HIGH DOSE OF RADIATION]

The objective of this researsh is to study the effects of Eminium Regelii phytopreparation (ERP) on immune status and free radical oxidation in the tissues of the adrenal glands and immunocompetent organs after combined exposure to 6 Gy dose of gamma irradiation and coal dust (remote period). The study was realized on 30 white laboratory male rats of the Wistar line, weighing 240±20g, that were divided into equal 3 groups: I group - intact, ІІ group - were exposured to combined effects of coal dust and gamma irradiation, III group - were exposured to combined effects and in parallel taking phytopreparation Eminium Regel. The animals of II and III groups were irradiated 90 days prior to the study at the TERAGAM 60Co radiotherapy unit ("ISOTREND spol. S.r.o.", Czech Republic) in dose of 6 Gy once. Experimental animals received phytopreparation of ER 2.5 mg/kg per day on calculate of body mass for 14 days. The results of the conducted studies showed that in the long-term period after the actions of the sublethal dose of gamma radiation and coal dust, significant changes were revealed that were characterized by a decrease in immunological reactivity, increased lipoperoxidation and inhibition of antioxidant defense activity of the organism. After exposure to ER, oxidative stress was alleviated, sufficient restoration of antioxidant protection and immune system indices, which were disrupted by the combined effects of a single high dose of radiation and a prolonged three-month inhalation of coal dust.

An efficient and robust MRI-guided radiotherapy planning approach for targeting abdominal organs and tumours in the mouse

INTRODUCTION

Preclinical CT-guided radiotherapy platforms are increasingly used but the CT images are characterized by poor soft tissue contrast. The aim of this study was to develop a robust and accurate method of MRI-guided radiotherapy (MR-IGRT) delivery to abdominal targets in the mouse.

METHODS

A multimodality cradle was developed for providing subject immobilisation and its performance was evaluated. Whilst CT was still used for dose calculations, target identification was based on MRI. Each step of the radiotherapy planning procedure was validated initially in vitro using BANG gel dosimeters. Subsequently, MR-IGRT of normal adrenal glands with a size-matched collimated beam was performed. Additionally, the SK-N-SH neuroblastoma xenograft model and the transgenic KPC model of pancreatic ductal adenocarcinoma were used to demonstrate the applicability of our methods for the accurate delivery of radiation to CT-invisible abdominal tumours.

RESULTS

The BANG gel phantoms demonstrated a targeting efficiency error of 0.56 ± 0.18 mm. The in vivo stability tests of body motion during MR-IGRT and the associated cradle transfer showed that the residual body movements are within this MR-IGRT targeting error. Accurate MR-IGRT of the normal adrenal glands with a size-matched collimated beam was confirmed by γH2AX staining. Regression in tumour volume was observed almost immediately post MR-IGRT in the neuroblastoma model, further demonstrating accuracy of x-ray delivery. Finally, MR-IGRT in the KPC model facilitated precise contouring and comparison of different treatment plans and radiotherapy dose distributions not only to the intra-abdominal tumour but also to the organs at risk.

CONCLUSION

This is, to our knowledge, the first study to demonstrate preclinical MR-IGRT in intra-abdominal organs. The proposed MR-IGRT method presents a state-of-the-art solution to enabling robust, accurate and efficient targeting of extracranial organs in the mouse and can operate with a sufficiently high throughput to allow fractionated treatments to be given.

Stress-associated radiation effects in pygmy wood mouse Apodemus uralensis (Muridae, Rodentia) populations from the East-Urals Radioactive Trace

This work is based on the comparative analysis of data obtained in the course of monitoring pygmy wood mouse populations (Apodemus uralensis Pallas, 1811) in the East-Urals Radioactive Trace (EURT) area and background territories. The effect of population size and its interaction with the radioactivity on biochemical parameters in the spleen and adrenal glands was studied. The concentrations of total lipids, proteins, DNA and RNA, activity of glucose-6-phosphate isomerase and catalase as well as the level of lipid peroxidation (LPO) were evaluated. The functional-metabolic shifts seen with large population sizes were characterized by delipidisation of adrenocortical cells, increased LPO as the main mechanism for steroidogenesis, growth of the protein components of the adrenal glands to maintain their hyperfunction, as well as immunosuppression associated with the restriction of carbohydrates providing splenocytes, reduction of DNA synthesis, and the development of a pro-/antioxidant imbalance. Reactivity of the neuroendocrine and hematopoietic systems of animals experiencing a high population density was higher in the EURT zone compared with the reference group. This difference can be explained by the additional stress from the chronic radiation exposure. The level of LPO, catalase activity, and DNA/protein ratio in the spleen and the total protein content in the adrenal glands were the most sensitive to the interaction of population size and radiation exposure. The harmful effect (distress) of the interaction of non-radiation and radiation factors can manifest when there is a population abundance above 30 ind./100 trap-day and a radiation burden which exceeds the lower boundary of the Derived Consideration Reference Levels, which is above 0.1 mGy/day.

Estimation of organ doses to patients undergoing hepatic chemoembolization procedures

The aim of this study is to evaluate organ and tissue absorbed doses to patients undergoing hepatic chemoembolization procedures performed in two hospitals in the city of Recife, Brazil. Forty eight patients undergoing fifty hepatic chemoembolization procedures were investigated. For the 20 cases with PA projection only, organs and tissues dose to KAP conversion coefficients were calculated using the mesh-based anthropometric phantom series FASH and MASH coupled to the EGSnrc Monte Carlo code. Clinical, dosimetric and irradiations parameters were registered for all patients. The maximum organ absorbed doses found were 2.4 Gy, 0.85 Gy, 0.76 Gy and 0.44 Gy for skin, kidneys, adrenals and liver, respectively.

Light stimulates the mouse adrenal through a retinohypothalamic pathway independent of an effect on the clock in the suprachiasmatic nucleus

The brain's master circadian pacemaker resides within the hypothalamic suprachiasmatic nucleus (SCN). SCN clock neurons are entrained to the day/night cycle via the retinohypothalamic tract and the SCN provides temporal information to the central nervous system and to peripheral organs that function as secondary oscillators. The SCN clock-cell network is thought to be the hypothalamic link between the retina and descending autonomic circuits to peripheral organs such as the adrenal gland, thereby entraining those organs to the day/night cycle. However, there are at least three different routes or mechanisms by which retinal signals transmitted to the hypothalamus may be conveyed to peripheral organs: 1) via retinal input to SCN clock neurons; 2) via retinal input to non-clock neurons in the SCN; or 3) via retinal input to hypothalamic regions neighboring the SCN. It is very well documented that light-induced responses of the SCN clock (i.e., clock gene expression, neural activity, and behavioral phase shifts) occur primarily during the subjective night. Thus to determine the role of the SCN clock in transmitting photic signals to descending autonomic circuits, we compared the phase dependency of light-evoked responses in the SCN and a peripheral oscillator, the adrenal gland. We observed light-evoked clock gene expression in the mouse adrenal throughout the subjective day and subjective night. Light also induced adrenal corticosterone secretion during both the subjective day and subjective night. The irradiance threshold for light-evoked adrenal responses was greater during the subjective day compared to the subjective night. These results suggest that retinohypothalamic signals may be relayed to the adrenal clock during the subjective day by a retinal pathway or cellular mechanism that is independent of an effect of light on the SCN neural clock network and thus may be important for the temporal integration of physiology and metabolism.

Effects and safety of ¹³¹I-metaiodobenzylguanidine (MIBG) radiotherapy in malignant neuroendocrine tumors: results from a multicenter observational registry

Effective treatments for malignant neuroendocrine tumors are under development. While iodine-131 metaiodobenzylguanidine (¹³¹I-MIBG) radiotherapy has been used in the treatment of malignant neuroendocrine tumors, there are few studies evaluating its therapeutic effects and safety in a multicenter cohort. In the current study, we sought to evaluate the effects and safety of ¹³¹I-MIBG therapy for conditions including malignant pheochromocytoma and paraganglioma within a multicenter cohort. Forty-eight malignant neuroendocrine tumors (37 pheochromocytoma and 11 paraganglioma) from four centers underwent clinical ¹³¹I-MIBG radiotherapy. The tumor responses were observed before and 3 to 6 months after the ¹³¹I-MIBG radiotherapy in accordance with RECIST criteria. We also evaluated the data for any adverse effects. The four centers performed a total of 87 ¹³¹I-MIBG treatments on 48 patients between January 2000 and March 2009. Of the treatments, 65 were evaluable using RECIST criteria. One partial response (PR), 40 stable disease (SD), and 9 progressive disease (PD) in malignant pheochromocytoma were observed after each treatment. Fourteen SD and one PD-were observed in paraganglioma. Patients with normal hypertension (systolic blood pressure (BP) > 130 mmHg) showed significantly reduced systolic BP after the initial follow-up (n=10, 138.1±8.2 to 129.5±13.5 mmHg, P=0.03). In adult neuroendocrine tumors with a treatment-basis analysis, there were side effects following 41 treatments (47.1%) and most of them (90.2%) were minor. In this multicenter registry, PR or SD was achieved in 84.6% of the treatment occasions in adult neuroendocrine tumors through ¹³¹I-MIBG radiotherapy. This indicated that most of the ¹³¹I-MIBG radiotherapy was performed safely without significant side effects.

Timed maternal melatonin treatment reverses circadian disruption of the fetal adrenal clock imposed by exposure to constant light

Surprisingly, in our modern 24/7 society, there is scant information on the impact of developmental chronodisruption like the one experienced by shift worker pregnant women on fetal and postnatal physiology. There are important differences between the maternal and fetal circadian systems; for instance, the suprachiasmatic nucleus is the master clock in the mother but not in the fetus. Despite this, several tissues/organs display circadian oscillations in the fetus. Our hypothesis is that the maternal plasma melatonin rhythm drives the fetal circadian system, which in turn relies this information to other fetal tissues through corticosterone rhythmic signaling. The present data show that suppression of the maternal plasma melatonin circadian rhythm, secondary to exposure of pregnant rats to constant light along the second half of gestation, had several effects on fetal development. First, it induced intrauterine growth retardation. Second, in the fetal adrenal in vivo it markedly affected the mRNA expression level of clock genes and clock-controlled genes as well as it lowered the content and precluded the rhythm of corticosterone. Third, an altered in vitro fetal adrenal response to ACTH of both, corticosterone production and relative expression of clock genes and steroidogenic genes was observed. All these changes were reversed when the mother received a daily dose of melatonin during the subjective night; supporting a role of melatonin on overall fetal development and pointing to it as a 'time giver' for the fetal adrenal gland. Thus, the present results collectively support that the maternal circadian rhythm of melatonin is a key signal for the generation and/or synchronization of the circadian rhythms in the fetal adrenal gland. In turn, low levels and lack of a circadian rhythm of fetal corticosterone may be responsible of fetal growth restriction; potentially inducing long term effects in the offspring, possibility that warrants further research.

Determination of human absorbed dose of 201Tl(III)-DTPA-HIgG based on biodistribution data in rats

To estimate the absorbed dose in normal organs and inflamed tissue following i.v. administration of [201Tl](III)-DTPA-HIgG by using biodistribution data in inflamation bearing rats was attempted. The percentages of injected dose per gram of each organ were calculated. The medical internal radiation dose formulation was applied to calculate the absorbed dose for various organs. The inflamed tissue to blood activity concentration ratios were about 19 and 23.3 at 24 and 28 h post-injection, respectively. A 185-MBq injection of 201Tl-DTPA-HIgG into the human body, might result in an estimated absorbed dose of 14.4 mGy for the total body and the highest absorbed dose was in the kidney with 1195 (mGy) and second to the Spleen were the liver, the lungs and the adrenals, which received 250.5 (mGy), 58.64 (mGy) and 56.44 (mGy), respectively. Biodistribution of [201Tl](III)-DTPA-HIgG demonstrated significant inflamed tissue uptake and low muscle and blood uptake, allowing for imaging of inflamed tissues.

Deformable adult human phantoms for radiation protection dosimetry: anthropometric data representing size distributions of adult worker populations and software algorithms

Computational phantoms representing workers and patients are essential in estimating organ doses from various occupational radiation exposures and medical procedures. Nearly all existing phantoms, however, were purposely designed to match internal and external anatomical features of the Reference Man as defined by the International Commission on Radiological Protection (ICRP). To reduce uncertainty in dose calculations caused by anatomical variations, a new generation of phantoms of varying organ and body sizes is needed. This paper presents detailed anatomical data in tables and graphs that are used to design such size-adjustable phantoms representing a range of adult individuals in terms of the body height, body weight and internal organ volume/mass. Two different sets of information are used to derive the phantom sets: (1) individual internal organ size and volume/mass distribution data derived from the recommendations of the ICRP in Publications 23 and 89 and (2) whole-body height and weight percentile data from the National Health and Nutrition Examination Survey (NHANES 1999-2002). The NHANES height and weight data for 19 year old males and females are used to estimate the distributions of individuals' size, which is unknown, that corresponds to the ICRP organ and tissue distributions. This paper then demonstrates the usage of these anthropometric data in the development of deformable anatomical phantoms. A pair of phantoms--modeled entirely in mesh surfaces--of the adult male and female, RPI-adult male (AM) and RPI-adult female (AF) are used as the base for size-adjustable phantoms. To create percentile-specific phantoms from these two base phantoms, organ surface boundaries are carefully altered according to the tabulated anthropometric data. Software algorithms are developed to automatically match the organ volumes and masses with desired values. Finally, these mesh-based, percentile-specific phantoms are converted into voxel-based phantoms for Monte Carlo radiation transport simulations. This paper also compares absorbed organ doses for the RPI-AM-5th-height and -weight percentile phantom (165 cm in height and 56 kg in weight) and the RPI-AM-95th-height and -weight percentile phantom (188 cm in height and 110 kg in weight) with those for the RPI-AM-50th-height and -weight percentile phantom (176 cm in height and 73 kg in weight) from exposures to 0.5 MeV external photon beams. The results suggest a general finding that the phantoms representing a slimmer and shorter individual male received higher absorbed organ doses because of lesser degree of photon attenuation due to smaller amount of body fat. In particular, doses to the prostate and adrenal in the RPI-AM-5th-height and -weight percentile phantom is about 10% greater than those in the RPI-AM-50th-height and -weight percentile phantom approximating the ICRP Reference Man. On the other hand, the doses to the prostate and adrenal in the RPI-AM-95th-height and -weight percentile phantom are approximately 20% greater than those in the RPI-AM-50th-height and -weight percentile phantom. Although this study only considered the photon radiation of limited energies and irradiation geometries, the potential to improve the organ dose accuracy using the deformable phantom technology is clearly demonstrated.

[The use of drinking sulfate mineral water in combination with laser and magnetic-laser irradiation for primary prophylaxis of post-radiation disorders(experimental study)]

Experiments on laboratory rats have demonstrated that prophylactic use of drinkable sulfate mineral water in combination with laser and magnetolaser irradiation of adrenal glands produces a radioprotecive effect that was especially well apparent in the liver and less so in the testes. Simultaneously, the functional activity of the thymus decreased. Protection of the liver by the combination of the above factors was more pronounced than the effect of each of them applied separately.

[Comparative morphological analysis of peripheral endocrine glands in small mammals inhabiting areas with high levels of radioactive pollutants and exposed to chronic irradiation in laboratory experiments]

The comparative study of cellular-tissue reactions in endocrine organs (thyroid and suprarenal glands, ovary) of rodents exposed to radiation in natural conditions (Radium station in Komi Republic and 30-km zone of Chernobyl APP) and experimental conditions modeling the chronic exposure has been conducted. There is evidence that chronic irradiation in low doses causes morphological disorders in different levels of structural organization (cellular-tissue, organism and population levels). The experimental results showed that observed variations in thyroid, suprarenal glands and ovary by morphometric parameters reflect the natural changes in their functional activity (within the physiological limits). These changes are directed at the homeostasis maintenance in changed conditions and have a compensatory and adaptation character. The effects of low dose radiation influence with combination of other agents may be amplified at the cellular-tissue reactions level. In comparison with experimental results, the natural conditions (high level of radioactivity with alpha- and beta-emitters, high natural radionuclides, toxic elements and extreme climatic factors) induce more expressed changes as a significant increasing of chromosomal and genes mutations in cells, destructive processes in organs of endocrine system and disorders of reproductive functions.

Effects of nocturnal light on (clock) gene expression in peripheral organs: a role for the autonomic innervation of the liver

Background

The biological clock, located in the hypothalamic suprachiasmatic nucleus (SCN), controls the daily rhythms in physiology and behavior. Early studies demonstrated that light exposure not only affects the phase of the SCN but also the functional activity of peripheral organs. More recently it was shown that the same light stimulus induces immediate changes in clock gene expression in the pineal and adrenal, suggesting a role of peripheral clocks in the organ-specific output. In the present study, we further investigated the immediate effect of nocturnal light exposure on clock genes and metabolism-related genes in different organs of the rat. In addition, we investigated the role of the autonomic nervous system as a possible output pathway of the SCN to modify the activity of the liver after light exposure.

Methodology and Principal Findings

First, we demonstrated that light, applied at different circadian times, affects clock gene expression in a different manner, depending on the time of day and the organ. However, the changes in clock gene expression did not correlate in a consistent manner with those of the output genes (i.e., genes involved in the functional output of an organ). Then, by selectively removing the autonomic innervation to the liver, we demonstrated that light affects liver gene expression not only via the hormonal pathway but also via the autonomic input.

Conclusion

Nocturnal light immediately affects peripheral clock gene expression but without a clear correlation with organ-specific output genes, raising the question whether the peripheral clock plays a “decisive” role in the immediate (functional) response of an organ to nocturnal light exposure. Interestingly, the autonomic innervation of the liver is essential to transmit the light information from the SCN, indicating that the autonomic nervous system is an important gateway for the SCN to cause an immediate resetting of peripheral physiology after phase-shift inducing light exposures.

Endocrine consequences of childhood malignancies

Advances in cancer therapy over the last years have resulted in improved survival rates for pediatric cancer patients. However, new treatments are associated with short and long-term morbidity. The endocrine system is particularly sensitive to cancer therapies. Long-term survivors of childhood cancer are at risk for hypothalamic pituitary dysfunction, gonadal failure or disorders relating to pubertal progress, thyroid disease, obesity, disorders of lipid metabolism and disorders of bone and mineral metabolism. Long-term follow-up is indicated, as these disorders may not become apparent until adulthood.

Cranial irradiation modulates hypothalamic-pituitary-adrenal axis activity and corticosteroid receptor expression in the hippocampus of juvenile rat

Glucocorticoids, essential for normal hypothalamic-pituitary-adrenal (HPA) axis activity, exert their action on the hippocampus through two types of corticosteroid receptors: the glucocorticoid receptor (GR) and the mineralocorticoid receptor (MR). Recent studies report that exposure of juvenile rats to cranial irradiation adversely affects HPA axis stability leading to its activation along with radiation- induced inflammation. This study was aimed to examine the acute effects of radiation on HPA axis activity and hippocampal corticosteroid receptor expression in 18-day-old rats. Since immobilization was part of irradiation procedure, both irradiated and sham-irradiated animals were exposed to this unavoidable stress. Our results demonstrate that the irradiated rats exhibited different pattern of corticosteroid receptor expression and hormone levels compared to respective controls. These differences included upregulation of GR protein in the hippocampus with a concomitant elevation of GR mRNA and an increase in circulating level of corticosterone. In addition, the expression of MR, both at the level of protein and gene expression, was not altered. Taken together, this study demonstrates that cranial irradiation in juvenile rats leads to enhanced HPA axis activity and increased relative GR/MR ratio in hippocampus. The present paper intends to show that neuroendocrine response of normal brain tissue to localized irradiation comprise both activation of HPA axis and altered corticosteroid receptor balance, probably as consequence of innate immune activation.

Work-up and management of paediatric Cushing's syndrome

PURPOSE OF REVIEW

Paediatric Cushing's syndrome presents a diagnostic and therapeutic challenge. Most paediatric endocrinologists have limited experience in managing children or adolescents with Cushing's syndrome and thus benefit from close consultation with adult colleagues. A protocol for investigation of the child with suspected Cushing's syndrome is presented followed by principles of management.

RECENT FINDINGS

Cushing's syndrome is rare in childhood, but causes serious morbidity. Investigations have evolved and now include new genetic and imaging techniques as well as classical endocrine studies. In Cushing's disease trans-sphenoidal surgery has transformed management, although only a few surgeons have experience in children. Pituitary radiotherapy is effective second-line therapy.

SUMMARY

Early diagnosis and treatment of Cushing's syndrome is vital for long-term outcome. The overall prognosis for Cushing's syndrome is good but challenges remain to ensure normal postcure growth and body composition.

[Clinical efficacy of target low-intensity laser radiation on the adrenal projection region in patients with bronchial asthma]

AIM

To study efficacy of infrared laser radiation on the adrenal projection region in patients with bronchial asthma (BA).

MATERIAL AND METHODS

The adrenal region of BA patients was exposed to infrared laser radiation. The effect was stated after blood count, examination of the urine and sputum, blood biochemical tests, blood hydrocortisone assay.

RESULTS

Positive clinical response to laser therapy manifested with improvement of clinical, device and spirometric indices in BA patients. Blood levels of hydrocortisone normalized.

CONCLUSION

Infrared laser radiation of adrenal projection region reduced the number of asphyxia attacks, improved bronchial drainage, shortened the disease duration. The method is well tolerated, safe, easy to make and suggested for use in combined treatment of BA.

Paired-organ and other selected absorbed fraction for the Korean Reference Adult Male model

The authors have developed a mathematical model for calculating internal radionuclide dosimetry for the Korean Reference Adult Male, and have also derived paired-organ and other selected inter-organ photon-specific absorbed fractions for this model. Each lung, kidney and adrenal gland was set as a separate source region even though each of them shares an identical physiological function with their complementary half. The thyroid gland was also set as a source region. Specific absorbed fractions (SAFs) were then derived by selecting 10 photon energies from 0.02 to 4.0 MeV inclusive. For this purpose the Monte Carlo methodology was used, and the derived SAF was compared with the resulting value of MIRD Pamphlet No. 5 and ORNL TM-8381, both of which were derived on the basis of the ICRP-23 reference man. The comparison showed that MIRD No. 5 and ORNL TM-8381 resulted in a higher absorbed fraction, but the phantom created on the basis of the Korean reference man led to a higher SAF. The weight of the organs of the phantom, and the size and location of the trunk seem to account for the differences. The energy-dependent differences in the SAFs are considered to be related to the distance between the source and target regions, the composition of the intervening tissues, and the photon energies and mean free paths. Also, as a result of deriving SAFs after setting each separate lung, kidney and adrenal gland as a source region, it was found that, although they are of the same physiological function, each individual organ serves as a source region on its own. Differences were noted in SAFs exerted on the source and target organs in accordance with the location of the organs, that is, whether they were located to the left or right of the source organs. The SAF derived in this study can be used for a more accurate internal radionuclide dosimetry for Koreans and other Orientals whose physiology, lifestyle and dietary habits are similar to those of Koreans.

Light activates the adrenal gland: timing of gene expression and glucocorticoid release

Light is a powerful synchronizer of the circadian rhythms, and bright light therapy is known to improve metabolic and hormonal status of circadian rhythm sleep disorders, although its mechanism is poorly understood. In the present study, we revealed that light induces gene expression in the adrenal gland via the suprachiasmatic nucleus (SCN)-sympathetic nervous system. Moreover, this gene expression accompanies the surge of plasma and brain corticosterone levels without accompanying activation of the hypothalamo-adenohypophysial axis. The abolishment after SCN lesioning, and the day-night difference of light-induced adrenal gene expression and corticosterone release, clearly indicate that this phenomenon is closely linked to the circadian clock. The magnitude of corticostereone response is dose dependently correlated with the light intensity. The light-induced clock-dependent secretion of glucocorticoids adjusts cellular metabolisms to the new light-on environment.

Enlightening the adrenal gland

The secretion of glucocorticoid hormones is tightly regulated by the circadian clock and by negative humoral feedback loops, both acting on the hypothalamic-pituitary gland-adrenal axis. However, a new study Ishida et al., 2005 [this issue of Cell Metabolism) shows that light can influence the adrenal's glucocorticoid output by a more direct pathway.

Chronic exposure to constant light affects morphology and secretion of adrenal zona fasciculata cells in female rats

The effect of chronic exposure to light of adult Wistar rats on growth and function of adrenal zona glomerulosa (ZG) and zona fasciculata (ZF) were examined. The females were exposed to continuous light of 600 lux for 95 days, starting on day 30 of age. The controls were kept under a 12:12 h light-dark cycle, at ambient temperature. The rats were sacrificed by decapitation and the left adrenal gland of each animal was dissected out and prepared for morphometric analyses. In animals exposed to chronic lighting, the absolute and relative volume of ZG were insignificantly increased by 5% (p>0.05) compared to controls. The volume of ZG cells and their nuclei were insignificantly changed by 1% (p>0.05) in comparison with corresponding controls. The absolute and relative volume of ZF were significantly increased (by 14 and 9%, respectively; p<0.05), as compared to controls. The volume of ZF cells and their nuclei were significantly increased (by 12 and 9%, respectively; p<0.05). Serum concentration of corticosterone was also significantly (p<0.05) increased by 13% in light-exposed group in comparison with control rats. These findings suggest that continuous exposure of female rats to constant light increased growth and secretory activity of ZF cells.

Exposure to chronic noise and fractionated X-ray radiation elicits biochemical changes and disrupts body weight gain in rat

The aim was to assess the developmental and biochemical effects resulting from separate and combined exposures to radiation and noise in adult male Sprague-Dawley rats. For 21 days, animals were exposed daily (1) to whole-body 121 kVp X-ray exposure (cumulative dose=5 Gy), (2) to random intermittent noise band-limited between 0.4 and 20 kHz; 2 h day(-1) 86 decibels (dB) and (3) to combined exposures. Control animals were housed under ambient noise conditions 55 dB A-weighted (dBA) and sham-exposed to X-rays. Body weight gain was significantly reduced in animals exposed to either X-rays or noise, and the loss was more pronounced in animals exposed to both conditions. Neither plasma adrenocorticotropic hormone (ACTH) nor corticosterone was altered by the treatment conditions. This study corroborated previous reports that ionizing radiation exposure increased plasma levels of 8-hydroxy-2'-deoxyguanosine (8-OHDG), but no effect was observed in animals co-exposed to chronic noise. Plasma big-endothelin-1 (Big ET-1) was significantly reduced in animals exposed to a combination of noise and X-rays. The results indicated that (1) adaptation to chronic noise appeared to occur at the level of the hypothalamic pituitary adrenal (HPA) response, in spite of a compromise in overall body weight gain; and (2) ionizing radiation exposure might alter systems activated by stressor exposure and/or act independently to influence health outcomes.

[Effect of the perturbed geomagnetic field on the metabolism of the rat connective tissue during heat exposure]

The biochemical data of the researches of the perturbed geomagnetic field influence on the metabolism of the rat's connective tissue by the heating are presented. The possibility of adrenal glands reaction modification under using the perturbed geomagnetic field after high temperature is shown.

[Laser irradiation as a factor of primary prophylaxis of postradiation disorders of spermatogenesis in rats and their progeny]

Experiments on male rats have established that preventive use of low-intensive impulse laser radiation (200-400 Hz) on the adrenals prevented and limited development of postradiation disorders of spermatogenesis in irradiated male rats and their progeny.

Effects of whole-body 50-Hz magnetic field exposure on mouse Leydig cells

The main goal of this study was to evaluate the possible effect of whole-body magnetic field (MF) exposure on the steroidogenic capacity of Leydig cells in vitro. In four separate experiments, male CFLP mice were exposed to sinusoidal 50-Hz, 100-microT MF. The duration of exposure was 23.5 h/day over a period of 14 days. At the end of the exposure, interstitial (Leydig) cells were isolated from the testicles of the sham-exposed and exposed animals. The cells were cultured for 48 h in the presence or absence of 1, 10, or 100 mIU/ml human chorionic gonadotropin (hCG). The luteinizing hormone (LH) analog hCG was used to check the testosterone (T) response of the sham-exposed controls and to evaluate the possible effect of the whole-body MF exposure on the steroidogenic capacity of Leydig cells in vitro. Testosterone content of the culture media and blood sera was measured by radioimmunoassay (RIA). In the cultures obtained from MF-exposed animals, the hCG-stimulated T response was significantly higher (p < 0.01) compared with the sham-exposed controls, while the basal T production of cells and the level of serum T remained unaltered. No MF exposure-related histopathological alterations were found in testicles, epididymes, adrenals, prostates, and pituitary glands. The MF exposure did not affect the animal growth rate and the observed hematologic and serum chemical variables. Our results indicate a presumably direct effect of whole-body MF exposure on the hCG-stimulated steroidogenic response of mouse Leydig cells.

Differential qualitative and temporal changes in the response of the hypothalamus-pituitary-adrenal axis in rats after localized or total-body irradiation

Stress such as exposure to ionizing radiation is able to activate the hypothalamus-pituitary-adrenal axis. The present study sought to examine the effects of different configurations of a 10-Gy gamma irradiation in rats on the hypothalamus-pituitary-adrenal axis to understand the mechanism of negative feedback by glucocorticoids induced by ionizing radiation. Specifically, we determined adrenocorticotropin and corticosterone levels in plasma as well as corticotrophin-releasing factor expression in the paraventricular nucleus of the hypothalamus by in situ hybridization from 6 h to 4 days after total-body, abdominal or head irradiation. In this study, we found an activation of the hypothalamus-pituitary-adrenal axis after radiation exposure. Plasma adrenocorticotropin and corticosterone levels were significantly increased after total-body and abdominal irradiation 3 days after exposure, in parallel with decreased labeling of corticotrophin-releasing factor mRNA in the parvocellular region of the paraventricular nucleus of the hypothalamus. Our results suggest that ionizing radiation activates the neuroendocrine system to protect the organism from the occurrence of radiation-induced inflammation.

[Effect of external ionizing radiation on morphofunctional indices of the hypothalamus, hypophysis and adrenal glands]

The laboratory rats exposed to one-time external ionizing radiation have been found to have phase changes of morphofunctional and secretory cells activity of hypothalamus, hypophysis, cortex and medullary of adrenal glands. The first phase called reactive (3-7 days) is characterized by enhancing energy-producing, protein-synthesizing and secretory functions of secretory sells of hypothalamus supraoptic nucleus, corticotrophic cells of adenohypophysis, adrenocorticytes of cortex and adrenocytes of medullary of adrenal glands. The second phase of dystrophic changes (7-14) is characterized by different degree of distrophic-destructive changes. The third phase (14-1 month) is characterized by compensatory adaptative and recovery processes during which we can see on the background of dystrophic changes the processes of intracellular reparative regeneration. The fourth phase (1-3 months) is characterized by virtually complete recovery of morphofunctional and secretory activity of most cells of hypothalamus, hypophysis and adrenal glands.

[Regenerative activity of muscle allografts and thymus status during long-term laser exposure of adrenals and homoplasty region prior to transplantation]

Cross allografting of both gastrocnemius muscles between intact rats and those with the adrenal and right shin preirradiated with a He-Ne laser (632.8 nm, 2.5-3.0 mW/cm2, 10 sessions within 14 days with the cumulative dose being 15-18 J/cm2 per rat). By the time of grafting, the adrenal activity decreased while the activity of thymus decreased. As a result, the allogenic muscle tissue was resorbed in the irradiated rats, particularly, in the right irradiated shin. At the same time, reinnervation of the grafts with a certain amount of survived allogenic muscle tissue was more active in the right irradiated shin as compared to the left intact one. Survival of the donor muscle tissue and its improved reinnervation was observed in a higher proportion of grafts in the intact rats. The allografts from the right preirradiated shin of animals with irradiated adrenal proved to be more viable as compared to the left intact shin.

Growth following malignancy

Disturbed growth in the child surviving cancer is multifactorial. This chapter examines the evidence for, and the difficulties in determining, individual drug treatment or disease effects at multiple endocrine levels influencing growth and against a changing baseline of adjuvant cancer therapies with potentially additive toxicity. The evolutionary pattern and potential aetiology of the neuro-endocrine deficit and growth-plate disturbance, the (unrandomized) effects of hormone replacement therapy and areas which require further study are also addressed. The reasons why growth hormone (GH) secretion is so exquisitely sensitive to disturbance, even though deficiencies soon after lesser cranial insults can be difficult to detect, are explored with evidence cited from the few existing prospective and interventional studies. The extent and nature of the hypothalamo-pituitary disturbance needs further prospective interventional study and disease-site- and treatment-specific comparisons. Practical treatment and surveillance strategies to optimize growth potential, age-appropriate development, peak bone mineral accretion, hair re-growth and future health and well-being are also suggested. Health-related outcomes resulting from today's newer therapies and enhanced surveillance need documenting in future (inter)national cancer trials, where randomized studies of hormonal intervention may also become possible.

[Structure and functions of muscle allotransplants developing in adrenals and the alloplasty area after long-term exposure]

The cross allotransplantation of right gastrocnemius muscles was carried out between intact rats and rats in which adrenals and right shins were subjected to low-energy He-Ne laser radiation (10 procedures for 2 weeks, the exposure duration 5 min; total dose for each rat 15-18 J/cm2). By conditions of experiment, the rats in each series were both donors and recipients, and hence the heterogeneity of rats in each series was the same. It was shown that the laser radiation in the dose studied and the regimes of exposure of rat adrenals and shin (area of the planned allotransplantation) influenced the muscle alloplasty. In rats with irradiated adrenals and shin, the disintegration and resorption of muscle allografts occurred more actively. In intact rats, muscle allografts were more viable. The allogenic muscle tissue and a weak contractile reaction of allografts were revealed in most of them. The allografts showed a moderate lymphocytic infiltration. The data obtained indirectly evidence that the transplant immune reaction increased in rats with irradiated adrenals and shin. In intact rats, the transplant immune reaction to irradiated m.gastrocnemius from irradiated shin decreased.

[Secretory activity of adrenal glands in the offspring of white rats in conditions of low-intensity radiation effects]

It has been shown that in offsprings of both sex F1, one or both parents (F0) of which were exposed to X-ray radiation at a dose of 1 Gy (the dose rate was 0.4 Gy/min), and in offsprings of 6 generations (F1-F6), parents (F0) of which were placed in to the Chernobyl zone at a pubertal age, the hypertrophy and hyperactivity of isolated adrenals were observed in the different periods of life. The decrease of adrenals' reactivity in response to ACTH (0.1 ED/ml) was found in males of all generations. Most expressed damages of adrenal glands' reactivity were marked in males F6.

Nocturnal illumination maintains reproductive function and simulates the period-lengthening effect of constant light in the mature male Djungarian hamster (Phodopus sungorus)

Mature male Djungarian hamsters (Phodopus sungorus) were placed in individual light-tight, sound attenuated chambers and exposed to one of four lighting conditions for a duration of approximately seven weeks. The four lighting conditions were: constant light (LL); constant dark (DD); feedback lighting (LDFB; a condition that illuminates the cage in response to locomotor activity); or a feedback lighting neighbor control (LDFB NC; the animal receives the same light pattern as a paired animal in feedback lighting, but has no control over it). Exposure of hamsters to LL or LDFB produced significantly and similarly longer free-running periods of the locomotor activity rhythm than exposure of animals to DD. Hamsters exposed to LDFB NC did not free-run or entrain, but rather displayed "relative coordination". The paired testes and sex accessory glands weights suggest that in the Djungarian hamster, LL and LDFB exposed animals maintained reproductive function, whereas DD exposed animals did not. Animals exposed to LDFB NC had intermediate paired testes weights. Since several previous studies have demonstrated that short pulses of light, which are coincident with the subjective night, are photostimulatory, it is not surprising that LDFB maintained reproductive function in the mature Djungarian hamster. Feedback lighting, however, has been shown to be an insufficient stimulus to maintain reproductive function of mature male and female Syrian hamsters, and to the reproductive maturation of immature Djungarian hamsters. The results suggest that there may be slight, but significant differences in the way these two species interpret photoperiod, as well as a developmental change in the photoperiodic response of Djungarian hamsters.

[The correction of the subcellular postradiation changes in the hypothalamus and parathyroid gland by using low-intensity laser radiation (an experimental study)]

The exposure of the rat adrenals 30 days after radiation (1 Gy) to low-intensity infrared laser radiation arrests development of ultrastructural disorders in the cells of hypothalamus and parathyroid gland, enhances subcellular manifestations of adaptation and rehabilitation processes.

[Effect of small doses of ionizing radiation on the level of catecholamines and corticosteroids in mouse adrenals]

Effects of 137Cs gamma-radiation (0.06-0.54 cGy, 0.06 cGy/day) on the levels of catecholamines and corticosteroids in mouse adrenals were investigated. There were observed increase of these parameters after mice irradiation during 1-2 days and their decrease after mice irradiation during 9 days.

[Adrenergic nerve plexuses of heart and adrenal and myocardial catecholamines of spontaneously hypertensive rats under the influence of electromagnetic irradiation in the millimeter range]

Condition of adrenergic cardiac and adrenal nervous plexuses of Kyoto-Wistar Rats (WKY) and spontaneously hypertensive rats (SHR) was examined by quantitative neurohistochemical methods before and after extremely high frequency field (EHF field) influence of "Bayur" microwave therapy apparatus in mode 1 (42,194 MHz frequency, 7.1 mm wavelength) and in mode 3 (53,534 MHz frequency, 5.6 mm wavelength). Reduction of myocardial nervous plexus density and catecholamine luminescence intensity were detected in SHR, as well as decrease of adrenal glands relative weight and catecholamine luminescence intensity in adrenal medulla of SHR, that is indicative of suppression of sympatho-adrenal system of hypertensive animals by EHF field influence in medical operating modes.

Induction of ovarian tumors by heavy ion irradiation in B6C3F1 mice

Six-week-old B6C3F1 mice were exposed to 0.439 Gy heavy ion irradiation as a 290 MeV/u carbon-ion beam (LET 10 keV/micron) at 2 cm from the upper proximal point of a spread Bragg beam and autopsied 13.5 months after the irradiation. In males total tumor incidences, mainly liver tumors, were 37.0% in irradiated group and 25.0% in control (P>0.05). In females the total tumor incidences were 32.3%, mainly ovarian tumors, in the irradiated group and 0% in the controls. These results indicate that heavy ion irradiation induces ovarian tumors in females but does not target any organ in males.

[The changes of serum cortisol and aldosterone in patients with cancer of vestibular section of larynx after irradiation and with and without surgery]

Enzyme immunoassay was used to measure serum levels of hydrocortisone and aldosterone in 85 patients with vestibular laryngeal cancer before treatment and after it. The treatment consisted of either radiation alone or radiation followed by surgery. Pretreatment examination revealed adrenal dysfunction evident from enhanced glucocorticoid and inhibited mineral corticoid activity. Radiotherapy alone or in combination with surgery gave rise to a trend to a decline in glucocorticoid activity and stimulated mineral corticoid activity.

[Several parameters of the state of the nervous, immune and endocrine systems in newborn rats exposed to irradiation during the preimplantation period of embryogenesis]

Protracted prenatal irradiation of animals at the preimplantation stage of embryogenesis is shown to produce disturbances in the development of regulation systems, with their consequences persisting up to sexually mature period of postnatal life. Unknown before, these effects of preimplantation irradiation give the experimental confirmation to the main statement of the previously proposed theoretical concept of the "systemic teratogenesis": the ultimate effect of prenatal irradiation is a distortion of the structure of postnatal neuroimmunoendocrine regulation in the direction of overdevelopment of its endocrine component with the following coadaptive underdevelopment of the nervous and immune components.

The impact of chronic radioactive stress on the immuno-physiological condition of small mammals

The mass of internal organs and cellularity index of thymus and spleen were measured in small mammals inhabiting territories with a low level of chronic irradiation caused by the Chernobyl accident. Comparing with uncontaminated territories from the same region, bank voles (Clethrionomys glareolus) demonstrated an increase in liver and thymus mass and cellularity index of thymus, while sub-adult shrews (Sorex araneus) at contaminated territories had larger body mass, heavier spleen, kidney, and liver. These changes reflect an increase of tension in physiological and immunological processes in the small mammal populations in response to chronic irradiation, which have a non-specific, stress-causing nature. Laboratory mice, exposed to a single dose of irradiation equal to the annual dose received by wild animals at contaminated territories (0.07 Gy), in contrast, showed decreased mass of kidney, spleen and thymus, and cellularity of thymus and spleen compared to the control group. This shows a direct and specific impact of a single dose of irradiation.

Hypoadrenocorticism in beagles exposed to aerosols of plutonium-238 dioxide by inhalation

Hypoadrenocorticism, known as Addison's disease in humans, was diagnosed in six beagles after inhalation of at least 1.7 kBq/g lung of 238PuO2. Histological examination of adrenal gland specimens obtained at necropsy revealed marked adrenal cortical atrophy in all cases. Autoradiographs showed only slight alpha-particle activity. Although the pathogenesis of adrenal cortical atrophy in these dogs is unclear, there is evidence to suggest an autoimmune disorder linked to damage resulting from alpha-particle irradiation to the lymphatic system.

p53 accumulation in the organs of low-dose X-ray-irradiated mice

In order to search for the direct evidence of cellular response to low-dose radiation, we investigated wild-type p53 protein accumulation in several organs of mice after exposure to low doses of X-rays. Significant p53 accumulation within 24 h was observed in the mouse adrenal glands and pancreas after X-ray irradiation at 25 cGy and 50 cGy, but not at 100 cGy. In addition, differential p53 accumulation was also observed in the hypophysis, thymus, skin, lung, bone marrow and liver at different doses. In contrast, we observed no accumulation of p53 protein in the spleen, testis or kidney at any dose used in this experiment. The p53 accumulation induced by low-dose X-rays in mice was organ-specific. It is suggested that cell type and interactions with other signal transduction pathways of the hormone system, immune system and/or nervous system may contribute to the variable induction of p53 by low-dose X-ray irradiation. The association of organ-specific p53 response with radiosensitivity and cancer incidence by radiation in each organ was discussed.

[The action of radioprotectors of natural origin (MIGI-K and carnosine) on the catecholamine level in irradiated rats]

The influence of natural radioprotectors (MIGI-K and carnosin) on the dynamics of catecholamines level in adrenal glands of irradiated rats was shown. Carnosin and MIGI-K take part in developing of organism radioresistance. Carnosin action is due to mobilisation of endogenous radioprotective agents (catecholamines) while MIGI-K influences on the restoring of their level.

Enhancement of mRNA in situ hybridization signal by microwave heating

BACKGROUND

Optimization of in situ hybridization protocols is of real interest when trying to detect small amounts of mRNA or when using low concentrations of probes. To enhance the hybridization signal, we have developed a modification of an in situ hybridization (ISH) protocol with radiolabeled cRNA probes. The detailed protocol of ISH used for paraffin sections is also described.

EXPERIMENTAL DESIGN

In microwave (MW) heating, the tissue sections are heated in a sodium citrate buffer (0.01 M, pH 6). The effects of the pretreatment with MW were studied on kidneys and adrenals of young rats and on human pathologic samples using [35S]-RNA probes complementary to the mRNAs of some components of the renin angiotensin system.

RESULTS

The heating pretreatment with the MW permitted us to obtain an enhancement of the hybridization signal, especially when using low doses of radioactive probes. This enhancement could be evaluated to 60 to 120% by computer-assisted quantification of the signal. Furthermore, the histologic structures and the staining with toluidine blue were not impaired by the heating treatment.

CONCLUSIONS

The enhancing effect of the hybridization signal obtained using MW allows shorter autoradiographic exposure times and/or the use of lower concentrations of radioactive probes for the detection of mRNA or the detection of mRNA expressed at the threshold of detection with usual protocols.

[Modification of reactions of rats to the effect of weak variable magnetic fields using a stress factor]

Stress-factor (hypokinesia) modifies the reaction of the adaptation, which develops under the changeable magnetic fields influence with 8 Hz frequency and 5 microT induction. It's being corroborated by the decrease of nonspecific resistance in the initial adaptation period, by the increase of central nervous system excitability, by the absence of catecholamines accumulation in the hypothalamus and in adrenal glands.

[Gamma-aminobutyric acid content and activity of the enzyme synthesizing it in blood plasma of children exposed to ionizing radiation as a result of the accident at the Chernobyl nuclear power plant]

Marked individual fluctuations in blood levels of GABA and GDC revealed in 35 to 50% of adolescents exposed to ionizing radiation several years before indicate the presence of an imbalance in the GABA-ergic system. These children (with GABA-ergic system disturbances) represent a group at risk of developing remote effects of radiation exposure presenting as disturbed rhythms and terms of sexual maturation, of growth, thyroid and adrenal abnormalities, and they should be regularly checked up.

[The effect of radon baths at Khmel'nik health resort on the central hemodynamic indices, on thyroid function and on adrenal glucocorticoid function in hypertension patients]

As many as 63 patients with stage I, II hypertensive disease were examined. Characteristics of central hemodynamics were studied by means of tetrapolar thoracic rheography, the content of thyroid-stimulating hormone, thyroxin, triiodothyranine, hydrocortisone were determined by radioimmunologic method. All investigations were done before and after the patients having radon baths. Hypotensive effect of radon baths in hyperkinetic type hemodynamics was manifested by a significant drop in cardiac index and increase in specific peripheral resistance. In hypokinetic type hemodynamics there was a significant fall in average hemodynamic pressure, and improvement of the arteriole patency. The levels of thyroxin and hydrocortisone have raised significantly. The Khmel'nik health resort radon baths have hypotensive effect in HD patients, enhance the function of the thyroid gland and glucocorticoid function of the adrenals.

[Rapid metabolic changes in the blood and organs of rats under the influence of electron pulse radiation at superhigh doses]

Early metabolic changes have been studied in the peripheral blood, brain, adrenals, spleen, and liver of rats after irradiation with 500 Gy. Using ESR spectroscopy we showed the formation of a great amount of hemoglobin nitrosyl complexes and methemoglobin in the blood and spleen, thus suggesting that the endothelium-derived relaxing factor, nitric oxide (NO), was released due to irradiation stimulation and sharp hypoxia in brain. Polarographic data concerning the disturbance of brain mitochondrial function (activation of succinate hydrogenase oxidation) allowed a conclusion that hypoxia appeared after irradiation at superlethal doses. Antioxidative activity of lipids in various tissues differed in the rats with "the early loss of performance" syndrome and in normal rats. Possibility of ammonia intoxication of the brain soon after irradiation at superlethal doses has been discussed.