MRAP deficiency impairs adrenal progenitor cell differentiation and gland zonation

Melanocortin 2 receptor accessory protein (MRAP) is a single transmembrane domain accessory protein and a critical component of the hypothamo-pituitary-adrenal axis. MRAP is highly expressed in the adrenal gland and is essential for adrenocorticotropin hormone (ACTH) receptor expression and function. Human loss-of-function mutations in MRAP cause familial glucocorticoid (GC) deficiency (FGD) type 2 (FGD2), whereby the adrenal gland fails to respond to ACTH and to produce cortisol. In this study, we generated Mrap-null mice to study the function of MRAP in vivo. We found that the vast majority of Mrap−/− mice died at birth but could be rescued by administration of corticosterone to pregnant dams. Surviving Mrap−/− mice developed isolated GC deficiency with normal mineralocorticoid and catecholamine production, recapitulating FGD2. The adrenal glands of adult Mrap−/− mice were small, with grossly impaired adrenal capsular morphology and cortex zonation. Progenitor cell differentiation was significantly impaired, with dysregulation of WNT4/β-catenin and sonic hedgehog pathways. These data demonstrate the roles of MRAP in both steroidogenesis and the regulation of adrenal cortex zonation. This is the first mouse model of isolated GC deficiency and reveals the role of MRAP in adrenal progenitor cell regulation and cortex zonatio

Oncometabolite induced primary cilia loss in pheochromocytoma

Primary cilia are sensory organelles involved in regulation of cellular signaling. Cilia loss is frequently observed in tumors; yet, the responsible mechanisms and consequences for tumorigenesis remain unclear. We demonstrate that cilia structure and function is disrupted in human pheochromocytomas – endocrine tumors of the adrenal medulla. This is concomitant with transcriptional changes within cilia-mediated signaling pathways that are associated with tumorigenesis generally and pheochromocytomas specifically. Importantly, cilia loss was most dramatic in patients with germline mutations in the pseudohypoxia-linked genes SDHx and VHL. Using a pheochromocytoma cell line derived from rat, we show that hypoxia and oncometabolite-induced pseudohypoxia are key drivers of cilia loss and identify that this is dependent on activation of an Aurora-A/HDAC6 cilia resorption pathway. We also show cilia loss drives dramatic transcriptional changes associated with proliferation and tumorigenesis. Our data provide evidence for primary cilia dysfunction contributing to pathogenesis of pheochromocytoma by a hypoxic/pseudohypoxic mechanism and implicates oncometabolites as ciliary regulators. This is important as pheochromocytomas can cause mortality by mechanisms including catecholamine production and malignant transformation, while hypoxia is a general feature of solid tumors. Moreover, pseudohypoxia-induced cilia resorption can be pharmacologically inhibited, suggesting potential for therapeutic intervention

Anti-Inflammatory Effects of IKK Inhibitor XII, Thymulin, and Fat-Soluble Antioxidants in LPS-Treated Mice

The present study was designed to compare the anti-inflammatory effects of several agents applied in vivo, namely, a synthetic inhibitor of the NF-κB cascade, fat-soluble antioxidants, and the thymic peptide thymulin. Cytokine response in LPS-treated mice was analysed in tandem with the following parameters: the synthesis of inducible forms of the heat shock proteins HSP72 and HSP90α; activity of the NF-κB and SAPK/JNK signalling pathways; and TLR4 expression. Inflammation-bearing Balb/c male mice were pretreated with an inhibitor of IKK-α/β kinases (IKK Inhibitor XII); with thymulin; with dietary coenzyme Q9, α-tocopherol, and β-carotene; or with combinations of the inhibitor and peptide or antioxidants. Comparable anti-inflammatory effects were observed in inflammation-bearing mice treated separately with thymulin or with dietary antioxidants administered daily for two weeks before LPS treatment. When LPS-injected mice were treated with the inhibitor and antioxidants together, neither plasma cytokines, signal proteins, nor heat shock proteins recovered more efficiently than when mice were treated with these agents separately. In contrast to antioxidant diet, the thymulin was shown to increase the effect of IKK Inhibitor XII in preventing IKK activation in LPS-treated mice

Formation Regularities of Silicon-Polysaccaride-Containing Polyolate Hydrogels

This work was carried out in the framework of the state assignment of FASO of Russia (theme № AAAAA18-118020290116-5)

Biomimetic sol-gel mineralization of polysaccharides by silicon and titanium polyolates

In this work, we have demonstrated that in addition to silicon tetraglycerolate, a new water-soluble biocompatible polyolate precursors – silicon tetrapolyethylene glycolate Si[O(CH2CH2O)nH]4 [5, 6] and titanium tetrapolyethylene glycolate Ti[O(CH2CH2O)nH]4 [5] – can be successfully utilized in biomimetical mineralization of polysaccharides of various nature. By the example of chitosan (cationic), xanthan gum (anionic), and hydroxyethyl cellulose (uncharged) polysaccharides, an accelerating effect has been demonstrated on the gelation process and a stabilizing effect has been revealed on the hydrogels formed as transparent monoliths showing resistance to syneresis. Thus formed silicon- and titanium-containing 3D-network of gels is found to be polymeric and appears to have ordered amorphous morphostructure, which can be explained as caused by the influence from the polysaccharides serving as templates. The presence of polyolate bridges between silicon or titanium atoms in the polymeric network is characteristic of polyolate precursors only and is determined mainly by the nature of the precursor and by the contents of polyol and water in the system. The formation of polyolate bridges is facilitated by the low reactivity of the precursor, by low water content, and also by polyol excess in the system. The sol-gel process utilized to obtain the silicon- and titanium-polysaccharide-containing hydrogels proceeds under the mild conditions at room temperature, with no catalyst or any organic solved to be used, and thus can be regarded as belonging to the green chemistry methods that show promise for biomedical materials applications.This work was carried out in the framework of the Russian State Assignment (theme № АААА-А19-119011790134-1)

Down-regulation of HSP70 sensitizes gastric epithelial cells to apoptosis and growth retardation triggered by H. pylori

<p>Abstract</p> <p>Background</p> <p><it>H. pylori </it>infection significantly attenuated the expression of HSP70 in gastric mucosal cells. However, the role of HSP70 cancellation in <it>H. pylori</it>-associated cell damages is largely unclear.</p> <p>Methods</p> <p>Small interfering RNA (siRNA) was used to down-regulate HSP70 in gastric epithelial cell lines AGS. The transfected cells were then incubated with <it>H. pylori </it>and the functions of HSP70 suppression were observed by viability assay, cell cycle analyses and TUNEL assay. HSP70 target apoptotic proteins were further identified by Western blot.</p> <p>Results</p> <p>The inhibition of HSP70 has further increased the effect of growth arrest and apoptosis activation triggered by <it>H. pylori </it>in gastric epithelial cells. The anti-proliferation function of HSP70 depletion was at least by up-regulating p21 and cell cycle modulation with S-phase accumulation. An increase of apoptosis-inducing factor (AIF) and cytosolic cytochrome C contributes to the activation of apoptosis following down-regulation of intracellular HSP70. Extracellular HSP70 increased cellular resistance to apoptosis by suppression the release of AIF and cytochrome c from mitochondria, as well as inhibition of p21 expression.</p> <p>Conclusions</p> <p>The inhibition of HSP70 aggravated gastric cellular damages induced by <it>H. pylori</it>. Induction of HSP70 could be a potential therapeutic target for protection gastric mucosa from <it>H. pylori</it>-associated injury.</p

In vitro phosphorylation as tool for modification of silk and keratin fibrous materials

An overview is given of the recent work on in vitro enzymatic phosphorylation of silk fibroin and human hair keratin. Opposing to many chemical "conventional" approaches, enzymatic phosphorylation is in fact a mild reaction and the treatment falls within "green chemistry" approach. Silk and keratin are not phosphorylated in vivo, but in vitro. This enzyme-driven modification is a major technological breakthrough. Harsh chemical chemicals are avoided, and mild conditions make enzymatic phosphorylation a real "green chemistry" approach. The current communication presents a novel approach stating that enzyme phosphorylation may be used as a tool to modify the surface charge of biocompatible materials such as keratin and silk

Modulation of Cellular Hsp72 Levels in Undifferentiated and Neuron-Like SH-SY5Y Cells Determines Resistance to Staurosporine-Induced Apoptosis

Increased expression of Hsp72 accompanies differentiation of human neuroblastoma SH-SY5Y cells to neuron-like cells. By modulating cellular levels of Hsp72, we demonstrate here its anti-apoptotic activity both in undifferentiated and neuron-like cells. Thermal preconditioning (43°C for 30 min) induced Hsp72, leading to cellular protection against apoptosis induced by a subsequent treatment with staurosporine. Preconditioned staurosporine-treated cells displayed decreased Bax recruitment to mitochondria and subsequent activation, as well as reduced cytochrome c redistribution from mitochondria. The data are consistent with Hsp72 blocking apoptosis upstream of Bax recruitment to mitochondria. Neuron-like cells (with elevated Hsp72) were more resistant to staurosporine by all measured indices of apoptotic signaling. Use of stable transfectants ectopically expressing moderately elevated levels of Hsp72 revealed that such cells in the undifferentiated state showed enhanced resistance to staurosporine-induced apoptosis, which was even more robust after differentiation to neuron-like cells. Overall, the protective effects of differentiation, thermal preconditioning and ectopic Hsp72 expression were additive. The strong inverse correlation between cellular Hsp72 levels and susceptibility to apoptosis support the notion that Hsp72 acts as a significant neuroprotective factor, enabling post-mitotic neurons to withstand potentially lethal stress that induces apoptosis

АТРОФИЯ ПЕРЕШЕЙКА И КОРПУСА МОЗОЛИСТОГО ТЕЛА - НЕЗАВИСИМЫЙ МАРКЕР ТЯЖЕСТИ И ПРОГРЕССИРОВАНИЯ РАССЕЯННОГО СКЛЕРОЗА

The corpus callosum (CC) volume loss in patients with multiple sclerosis (MS) is a long been known phenomenon, considered by many authors as an indicator of disease severity. Meanwhile the relationship between CC atrophy and disease severity in MS patients not always found in studies, which may be due to the features of somatotopical CC structure. The aim of our study was to determine the relationship of atrophy in different parts of CC with the severity of clinical manifestations in MS patients to clarify the pathogenesis of these disorders and find opportunities for the development of tools for control and correction. The article presents results of morphometric analysis of 117 patients with different types of MS and 25 healthy volunteers. The original MRI image postprocessing algorithm is used. The initial parameters used for the statistical analysis were: age, duration of disease, the type of the disease, numerical score of FS and EDSS scales, the results of morphometry. Correlation analysis showed that the volume of the CC isthmus and corpus inversely correlated with disease duration and severity of a pyramidal, cerebellar, sensory, pelvic disorders and degree of disability. Analysis of variance in groups of patients with different types and severity of MS showed that atrophy of the CC isthmus and corpus is associated not only with the degree of disability, but also with the disease type. The study results confirm the important role of the atrophy of certain brain regions in the development of clinical picture and types of MS. It is shown that changes in the volume of the CC isthmus and corpus are independent markers of the development stage and severity of the disease, and their measurement can be an instrumental tool for objective assessment of the effectiveness of personalized neurorehabilitation techniques in patients with demyelinating diseases of the central nervous system.Уменьшение объема мозолистого тела (МТ) у больных с рассеянным склерозом (РС) - давно известный феномен, рассматриваемый многими авторами как показатель тяжести заболевания. В то же время далеко не во всех исследованиях выявлена взаимосвязь между атрофией МТ и выраженностью инвалидизации пациентов с РС, что может быть связано с особенностями соматотопической структуры МТ. Целью нашей работы было выявление взаимосвязи атрофии различных отделов МТ с выраженностью клинических проявлений РС для уточнения патогенеза данных нарушений и определения возможностей разработки инструментов их контроля и коррекции. Представлены результаты морфометрического анализа данных 117 пациентов с различными вариантами РС и 25 здоровых добровольцев. Использовался оригинальный алгоритм постпроцессинговой обработки МРТ-изображений. Исходные параметры для статистического анализа: возраст, длительность заболевания, тип течения заболевания, балльная оценка по шкалам FS и EDSS, результаты морфометрии. При корреляционном анализе было показано, что объемы перешейка и корпуса МТ обратно коррелируют с длительностью заболевания, а также с выраженностью пирамидных, мозжечковых, чувствительных, тазовых расстройств и степенью нетрудоспособности. Дисперсионный анализ в группах больных с различной тяжестью и вариантами течения РС выявил, что атрофия перешейка и корпуса МТ связана не только со степенью инвалидизации, но и с типом течения заболевания. Результаты исследования подтверждают важную роль атрофии отдельных регионов МРТ в развитии клинической картины и типа течения РС. Показано, что изменения объемов перешейка и корпуса МТ являются независимыми маркерами стадии развития и тяжести заболевания, а их измерение может быть инструментом объективной инструментальной оценки эффективности персонифицированных нейрореабилитационных методик у пациентов с демиелинизирующими заболеваниями ЦНС

Компьютерная томография и магнитно-резонансная томография диффузных аксональных повреждений при черепно-мозговой травме у детей младшего возраста: ретроспективное исследование

INTRODUCTION: Traumatic brain injury (TBI) is the leading cause of death and disability in children. Children’s TBI is associated with a number of characteristics that distinguish it from adults. Although the death rate associated with TBI has decreased over the past 2 decades, the disability of children who survived TBI continues to have a significant impact on the economy and public health of society as a whole.OBJECTIVE: To show the possibilities of computed tomography and magnetic resonance imaging in the diagnosis of traumatic diffuse axonal injuries in infants and young children.MATERIALS AND METHODS: In this work, we analyzed the CT and MRI data of 1334 children under 3 years of age with acute TBI who were treated at the Clinical and Research Institute of Emergency Pediatric Surgery and Trauma (730 boys, 604 girls). The age of the children was from 23 days to 3 years, the average age was 1 year 6 months. Computed tomography scans were performed on a 128-slice Ingenuity Elite scanner (Philips). Scanning of the area of interest (head + cervical spine) was carried out with the maximum possible reduction in indicators to minimize the radiation dose, including the iDose4 program. MRI was performed on a Phillips Achieva 3 T scanner with multiplanar T1- and T2WI, 2D and 3D isotropic images, FLAIR, SWI, DWI/DTI, and magnetic resonance angiography (MRA). No contrast enhancement was applied. Statistics: data processing was carried out using the GraphPad Prism 9 software package. The computing and graphic capabilities of the Excel spreadsheet editor were used. To compare the mean values of the data samples, ANOVA analysis of variance wasused; differences were considered significant at a significance level of p&lt;0.05.RESULTS: 824 (61.8%) of 1334 children had a concussion, 510 (38.2%) had traumatic injuries of skull and brain from uncomplicated cephalohematomas and linear fractures to massive intracranial hematomas and total brain edema. Diffuse axonal injuries(DAI) type I and II on CT, further confirmed by MRI, were detected in 32 (6.27%) of all 510 children with TBI. 19 out of 32 hada combination with brain contusions, 13 with epi — and / or subdural hematomas of a small volume. MRI was performed in 89 out of 510 children under 3 years of age with intracranial injuries, in whom CT was initially performed. DAI of various types were detected by MRI in 92.13% (82/89) of the patients.DISCUSSION: DAI is one of the most common types of TBI, occurring in both mild and severe forms, and is a brain injury characterized by axonal disruption, resulting in lesions of white matter tracts over a wide area. Taking into account the fact that children with TBI were admitted to the institute with a significant spread (from 1 hour to 7 days), the initial CT scan was performed no later than one hour after admission and was supplemented by MRI. The criteria for CT and MRI prescribements after TBI were: clinical and neurological status at the time of admission. CT has low sensitivity for detecting DAI, as only large hemorrhagic (hyperdense) lesions of DAI are detected. The use of multiplanar reconstruction, as well as various options, such as 3D reconstruction, MIP and MinIP (maximum and minimum intensity projection) and others, allows for a detailed assessment of the brain parenchyma and increases the detection of DAI. In our study, DAI using MRI was detected in 92.13% of patients, and the most critical type of DAI III was detected in 100% of children with severe TBI with poor outcome and death of patients.CONCLUSION: Head CT is the preferred method for emergency radiology of TBI patients due to its affordability, speed of data acquisition, and ability to detect lesions requiring urgent neurosurgical intervention. In acute cases, MRI is chosen for patients with severe neurological impairment despite the absence of structural brain damage on CT. MRI is the method of choice for subacute and chronic TBI ВВЕДЕНИЕ: Черепно-мозговая травма (ЧМТ) является ведущей причиной смерти и инвалидности у детей. Детская ЧМТ связана с  рядом характеристик, отличающих ее от  взрослых. Хотя уровень смертности, связанной с  ЧМТ, снизился за  последние два десятилетия, инвалидность детей, переживших ЧМТ, продолжает оказывать значительное влияние на экономику и общественное здравоохранение общества в целом.ЦЕЛЬ: Показать возможности компьютерной и магнитно-резонансной томографии в диагностике травматических диффузных аксональных повреждений у младенцев и детей младшего возраста.МАТЕРИАЛЫ И МЕТОДЫ: В данной работе мы проанализировали данные КТ и МРТ 1334 детей до 3 лет с острой ЧМТ, лечившихся в НИИ неотложной детской хирургии и травматологии (730 мальчиков и 604 девочек). Возраст детей был от 23 дней до 3 лет, средний возраст составил 1 год 6 месяцев. Компьютерная томография выполнена на 128-срезовом томографе Ingenuity Elite (Philips). Сканирование зоны интереса (голова+шейный отдел позвоночника) проводилось с максимально возможным снижением показателей для минимизации дозы облучения, включая программу iDose4. МРТ проведена на томографе Phillips Achieva 3 Тл с получением мультипланарных T1- и T2-ВИ, 2D- и 3D-изотропных изображений, FLAIR, SWI, ДВИ/ДТИ, магнитно-резонансной ангиографии (МРА). Контрастное усиление не применялось.Статистика: проводилась с помощью компьютерной программы GraphPad Prism 9. Использовались вычислительные и графические возможности редактора электронных таблиц Excel. Для сравнения средних значений выборок данных применялся дисперсионный анализ ANOVA, различия считались достоверными на уровне значимости р&lt;0,05.РЕЗУЛЬТАТЫ: У 824 (61,8%) из 1334 детей было сотрясение головного мозга, у 510 (38,2%) выявлены травматические повреждения черепа и головного мозга от неосложненных кефалогематом и линейных переломов до массивных внутричерепных гематом и тотального отека мозга. ДАП I и II типа при КТ, в дальнейшем подтвержденные при МРТ, выявлены у 32 (6,27%) детей из всех 510 с ЧМТ. У 19 из 32 было сочетание с ушибами головного мозга, 13 с эпи- и/или субдуральными гематомами небольшого объема. МРТ выполнена у 89 из 510 детей до 3 лет с интракраниальными повреждениями, у которых первично произведена КТ. Диффузные аксональные повреждения (ДАП) различного типа с помощью МРТ выявлены у 92,13% (82/89) пострадавших.ОБСУЖДЕНИЕ: ДАП является одним из наиболее частых видов ЧМТ и встречается как при легкой, так и при тяжелой степени, представляет собой повреждение головного мозга, характеризующееся разрывом аксонов, в результате чего возникают поражениями трактов белого вещества в большом пространстве. С учетом поступления в институт детей с ЧМТ со значительным разбросом (от 1 часа до 7 суток), первичную КТ проводили не позднее чем через один час после поступления и дополняли МРТ. Критерием назначения КТ и МРТ после ЧМТ служил клинический и неврологический статус на время поступления. КТ имеет низкую чувствительность обнаружения ДАП, так как выявляется только крупные геморрагические (гиперденсные) очаги ДАП. Использование мультипланарной реконструкции, а также различных опций, таких как 3D-реконструкция, MIP и  MinIP (проекция максимально и  минимальной интенсивности) и  другие, позволяют детально оценить паренхиму головного мозга и повысить выявляемость ДАП. В нашем исследовании ДАП с помощью МРТ выявлены у 92,13% пациентов, а наиболее критичный тип ДАП III — у 100% детей с тяжелой ЧМТ с плохим исходом и смертью пациентов.ЗАКЛЮЧЕНИЕ: КТ головы является предпочтительным методом для неотложной радиологии пациентов с ЧМТ из-за ее доступности, скорости получения данных и способности обнаруживать поражения, требующие срочного нейрохирургического вмешательства. В острых случаях МРТ назначается пациентам с тяжелыми неврологическими нарушениями, несмотря на отсутствие структурных повреждений головного мозга на КТ. МРТ является методом выбора при подострой и хронической ЧМТ