Tuberous Sclerosis Complex and the kidneys: what nephrologists need to know / Complexo da Esclerose Tuberosa e rins: o que os nefrologistas devem saber

Abstract Tuberous sclerosis complex (TSC) is an autosomal dominant disease characterized by the development of hamartomas in the central nervous system, heart, skin, lungs, and kidneys and other manifestations including seizures, cortical tubers, radial migration lines, autism and cognitive disability. The disease is associated with pathogenic variants in the TSC1 or TSC2 genes, resulting in the hyperactivation of the mTOR pathway, a key regulator of cell growth and metabolism. Consequently, the hyperactivation of the mTOR pathway leads to abnormal tissue proliferation and the development of solid tumors. Kidney involvement in TSC is characterized by the development of cystic lesions, renal cell carcinoma and renal angiomyolipomas, which may progress and cause pain, bleeding, and loss of kidney function. Over the past years, there has been a notable shift in the therapeutic approach to TSC, particularly in addressing renal manifestations. mTOR inhibitors have emerged as the primary therapeutic option, whereas surgical interventions like nephrectomy and embolization being reserved primarily for complications unresponsive to clinical treatment, such as severe renal hemorrhage. This review focuses on the main clinical characteristics of TSC, the mechanisms underlying kidney involvement, the recent advances in therapy for kidney lesions, and the future perspectives.

Resumo O complexo da esclerose tuberosa (CET) é uma doença autossômica dominante caracterizada pelo desenvolvimento de hamartomas no sistema nervoso central, coração, pele, pulmões e rins e outras manifestações, incluindo convulsões, tubérculos corticais, linhas de migração radial, autismo e deficiência cognitiva. A doença está associada a variantes patogênicas nos genes TSC1 ou TSC2, resultando na hiperativação da via mTOR, um importante regulador do crescimento e metabolismo celular. Consequentemente, a hiperativação da via mTOR leva à proliferação anormal do tecido e ao desenvolvimento de tumores sólidos. O envolvimento renal no CET é caracterizado pelo desenvolvimento de lesões císticas, carcinoma de células renais e angiomiolipomas renais, que podem progredir e causar dor, sangramento e perda da função renal. Nos últimos anos, houve uma mudança notável na abordagem terapêutica do CET, especialmente no tratamento das manifestações renais. Os inibidores de mTOR surgiram como a principal opção terapêutica, enquanto intervenções cirúrgicas como nefrectomia e embolização são reservadas principalmente para complicações que não respondem ao tratamento clínico, como hemorragia renal grave. Esta revisão se concentra nas principais características clínicas do CET, nos mecanismos subjacentes ao envolvimento renal, nos recentes avanços na terapia para lesões renais e nas perspectivas futuras.

Therapy with sirolimus in vascular anomalies: the experience of two Italian centers on 14 pediatric patients.

Introduction: Vascular anomalies (VAs) constitute a heterogeneous group of tumors and malformations capable of inducing significant clinical events in specific patients, such as the compression of vital organs, pain, functional impairment, or acquired coagulopathy. Molecular investigations into the underlying mechanisms of VAs have unveiled the frequent involvement of the PI3 K/AKT/mTOR pathway. Sirolimus, a specific mTOR inhibitor, has emerged as a potential therapeutic agent; however, its routine clinical application in complex VAs is currently restricted by a lack of extensive clinical experience. Methods: Between 2015 and 2024, we administered sirolimus to 14 pediatric patients with various types of vascular anomalies in two Italian centers, subjecting them to clinical and instrumental follow-up to investigate its efficacy and the possible occurrence of adverse events. Results: An overall improvement in or stability of their vascular anomalies was reported by 86% of patients. We also assessed toxicity, noting a low prevalence of life-threatening adverse events: only one case of sepsis was reported in a patient with a severe clinical condition, and four cases of recurrent aphthosis (28%) were reported. The most common side effect was dyslipidemia, with 43% of patients developing hypercholesterolemia (21%) or hypertriglyceridemia (21%), although these patients generally did not reach severe levels. Discussion: In line with data in the literature, according to our experience, medical therapy with sirolimus should be considered in pediatric patients affected by vascular anomalies.

The role of autophagy in the progression of HIV infected cardiomyopathy.

Although highly active antiretroviral therapy (HAART) has changed infection with human immunodeficiency virus (HIV) from a diagnosis with imminent mortality to a chronic illness, HIV positive patients who do not develop acquired immunodeficiency syndrome (AIDs) still suffer from a high rate of cardiac dysfunction and fibrosis. Regardless of viral load and CD count, HIV-associated cardiomyopathy (HIVAC) still causes a high rate of mortality and morbidity amongst HIV patients. While this is a well characterized clinical phenomena, the molecular mechanism of HIVAC is not well understood. In this review, we consolidate, analyze, and discuss current research on the intersection between autophagy and HIVAC. Multiple studies have linked dysregulation in various regulators and functional components of autophagy to HIV infection regardless of mode of viral entry, i.e., coronary, cardiac chamber, or pericardial space. HIV proteins, including negative regulatory factor (Nef), glycoprotein 120 (gp120), and transactivator (Tat), have been shown to interact with type II microtubule-associated protein-1 ß light chain (LC3-II), Rubiquitin, SQSTM1/p62, Rab7, autophagy-specific gene 7 (ATG7), and lysosomal-associated membrane protein 1 (LAMP1), all molecules critical to normal autophagy. HIV infection can also induce dysregulation of mitochondrial bioenergetics by altering production and equilibrium of adenosine triphosphate (ATP), mitochondrial reactive oxygen species (ROS), and calcium. These changes alter mitochondrial mass and morphology, which normally trigger autophagy to clear away dysfunctional organelles. However, with HIV infection also triggering autophagy dysfunction, these abnormal mitochondria accumulate and contribute to myocardial dysfunction. Likewise, use of HAART, azidothymidine and Abacavir, have been shown to induce cardiac dysfunction and fibrosis by inducing abnormal autophagy during antiretroviral therapy. Conversely, studies have shown that increasing autophagy can reduce the accumulation of dysfunctional mitochondria and restore cardiomyocyte function. Interestingly, Rapamycin, a mammalian target of rapamycin (mTOR) inhibitor, has also been shown to reduce HIV-induced cytotoxicity by regulating autophagy-related proteins, making it a non-antiviral agent with the potential to treat HIVAC. In this review, we synthesize these findings to provide a better understanding of the role autophagy plays in HIVAC and discuss the potential pharmacologic targets unveiled by this research.

Assessments of prostate cancer cell functions highlight differences between a pan-PI3K/mTOR inhibitor, gedatolisib, and single-node inhibitors of the PI3K/AKT/mTOR pathway.

Metastatic castration-resistant prostate cancer (mCRPC) is characterized by loss of androgen receptor (AR) sensitivity and oncogenic activation of the PI3K/AKT/mTOR (PAM) pathway. Loss of the PI3K regulator PTEN is frequent during prostate cancer (PC) initiation, progression, and therapeutic resistance. Co-targeting the PAM/AR pathways is a promising mCRPC treatment strategy but is hampered by reciprocal negative feedback inhibition or feedback relief. Most PAM inhibitors selectively spare (or weakly inhibit) one or more key nodes of the PAM pathway, potentiating drug resistance depending on the PAM pathway mutation status of patients. We posited that gedatolisib, a uniformly potent inhibitor of all class I PI3K isoforms, as well as mTORC1 and mTORC2, would be more effective than inhibitors targeting single PAM pathway nodes in PC cells. Using a combination of functional and metabolic assays, we evaluated a panel of PC cell lines with different PTEN/PIK3CA status for their sensitivity to multi-node PAM inhibitors (PI3K/mTOR: gedatolisib, samotolisib) and single-node PAM inhibitors (PI3Kα: alpelisib; AKT: capivasertib; mTOR: everolimus). Gedatolisib induced anti-proliferative and cytotoxic effects with greater potency and efficacy relative to the other PAM inhibitors, independent of PTEN/PIK3CA status. The superior effects of gedatolisib were likely associated with more effective inhibition of critical PAM-controlled cell functions, including cell cycle, survival, protein synthesis, oxygen consumption rate, and glycolysis. Our results indicate that potent and simultaneous blockade of all class I PI3K isoforms, mTORC1, and mTORC2 could circumvent PTEN-dependent resistance. Gedatolisib, as a single agent and in combination with other therapies, reported promising preliminary efficacy and safety in various solid tumor types. Gedatolisib is currently being evaluated in a Phase 1/2 clinical trial in combination with darolutamide in patients with mCRPC previously treated with an AR inhibitor, and in a Phase 3 clinical trial in combination with palbociclib and fulvestrant in patients with HR+/HER2- advanced breast cancer.

Metformin mitigates osteoarthritis progression by modulating the PI3K/AKT/mTOR signaling pathway and enhancing chondrocyte autophagy.

Osteoarthritis (OA) is a chronic degenerative disease characterized by overall joint tissue damage. Metformin (Met) has been shown to inhibit inflammatory reactions, though its potential protective mechanism on cartilage remains unclear. This study investigated Met's potential to protect cartilage in an OA rat model. Various morphological experiments were conducted to assess changes in cartilage tissue morphology before and after Met treatment. Protein and mRNA levels of cartilage-specific genes were measured using western blot, immunohistochemical staining, and RT-qPCR. Additionally, protein levels of autophagy-related and mTOR pathway-related proteins were measured. The results indicate an imbalance in the synthesis and degradation metabolism of chondrocytes, downregulation of cellular autophagy, and activation of the PI3K/Akt/mTOR pathway after surgery. However, treatment with Met could upregulate the expression of synthetic metabolic factors, indicating its contribution to cartilage repair. Furthermore, analysis of autophagy and pathway protein levels indicated that Met effectively attenuated autophagic damage to osteoarthritic cartilage cells and abnormal activation of the PI3K/Akt/mTOR pathway. In conclusion, Met can inhibit the abnormal activation of the PI3K/AKT/mTOR signaling pathway in cartilage tissue, promote the restoration of cartilage cell autophagic function, improve the balance of cartilage cell synthesis and degradation metabolism, and thus exert a protective effect on rat joint cartilage.

mTOR aggravated CD4+ T cell pyroptosis by regulating the PPARγ-Nrf2 pathway in sepsis.

Sepsis is a systemic inflammatory response syndrome caused by a dysregulated host response to infection. CD4+T cell reduction is crucial to sepsis-induced immunosuppression. Pyroptosis, a programmed necrosis, is concerned with lymphocytopenia. Peroxisome proliferator-activated receptor gamma (PPARγ) regulated by upstream mTOR, exerts anti-pyroptosis effects. To investigate the potential effects of mTOR-PPARγ on sepsis-induced CD4+T cell depletion and the underlying mechanisms, we observed mTOR activation and pyroptosis with PPARγ-Nrf suppression through cecal ligation and puncture (CLP) sepsis mouse model. Further mechanism research used genetically modified mice with T cell-specific knockout mTOR or Tuberous Sclerosis Complex1 (TSC1). It revealed that mTOR mediated CD4 + T cell pyroptosis in septic mice by negatively regulating the PPARγ-Nrf2 signaling pathway. Taken together, mTOR-PPARγ-Nrf2 signaling mediated the CD4+ T cell pyroptosis in sepsis, contributing to CD4+T cell depletion and immunosuppression.

FOXC1 transcriptionally suppresses ABHD5 to inhibit the progression of renal cell carcinoma through AMPK/mTOR pathway.

BACKGROUND: Increased activity of the transcription factor FOXC1 leads to elevated transcription of target genes, ultimately facilitating the progression of various cancer types. However, there are currently no literature reports on the role of FOXC1 in renal cell carcinoma. METHODS: By using RT-qPCR, immunohistochemistry and Western blotting, FOXC1 mRNA and protein expression was evaluated. Gain of function experiments were utilized to assess the proliferation and metastasis ability of cells. A nude mouse model was created for transplanting tumors and establishing a lung metastasis model to observe cell proliferation and spread in a living organism. Various techniques including biological analysis, CHIP assay, luciferase assay, RT-qRCR and Western blotting experiments were utilized to investigate how FOXC1 contributes to the transcription of ABHD5 on a molecular level. FOXC1 was assessed by Western blot for its impact on AMPK/mTOR signaling pathway. RESULTS: FOXC1 is down-regulated in RCC, causing unfavorable prognosis of patients with RCC. Further experiments showed that forced FOXC1 expression significantly restrains RCC cell growth and cell metastasis. Mechanically, FOXC1 promotes the transcription of ABHD5 to activate AMPK signal pathway to inhibit mTOR signal pathway. Finally, knockdown of ABHD5 recovered the inhibitory role of FOXC1 overexpression induced cell growth and metastasis suppression. CONCLUSION: In general, our study demonstrates that FOXC1 exerts its tumor suppressor role by promoting ABHD5 transcription to regulating AMPK/mTOR signal pathway. FOXC1 could serve as both a diagnostic indicator and potential treatment focus for RCC.

[Effect of 2-phenylethyl-beta-glucopyranoside isolated from Huaizhong No. 1 Rehmannia glutinosa on hypoxic pulmonary hypertension by regulating PI3K/Akt/m TOR/HIF-1α pathway].

The study investigated the protective effect and mechanism of 2-phenylethyl-beta-glucopyranoside(Phe) from Huaizhong No.1 Rehmannia glutinosa on hypoxic pulmonary hypertension(PH), aiming to provide a theoretical basis for clinical treatment of PAH. Male C57BL/6N mice were randomly divided into normal group, model group, positive drug(bosentan, 100 mg·kg~(-1)) group, and low-and high-dose Phe groups(20 and 40 mg·kg~(-1)). Except for the normal group, all other groups were continuously subjected to model induction in a 10% hypoxic environment for 5 weeks, with oral administration for 14 days starting from the 3rd week. The cardiopulmonary function, right ventricular pressure, cough and asthma index, lung injury, cell apoptosis, oxidative stress-related indicators, immune cells, and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR)/hypoxic inducible factor 1α(HIF-1α) pathway-related proteins or mRNA levels were examined. Furthermore, hypoxia-induced pulmonary arterial smooth muscle cell(PASMC) were used to further explore the mechanism of Phe intervention in PH combined with PI3K ago-nist(740Y-P). The results showed that Phe significantly improved the cardiopulmonary function of mice with PH, decreased right ventricular pressure, cough and asthma index, and lung injury, reduced cell apoptosis, oxidative stress-related indicators, and nuclear levels of phosphorylated Akt(p-Akt) and phosphorylated mTOR(p-mTOR), inhibited the expression levels of HIF-1α and PI3K mRNA and proteins, and maintained the immune cell homeostasis in mice. Further mechanistic studies revealed that Phe significantly reduced the viability and migration ability of hypoxia-induced PASMC, decreased the expression of HIF-1α and PI3K proteins and nuc-lear levels of p-Akt and p-mTOR, and this effect was blocked by 740Y-P. Therefore, it is inferred that Phe may exert anti-PH effects by alleviating the imbalance of oxidative stress and apoptosis in lung tissues and regulating immune levels, and its mechanism may be related to the regulation of the PI3K/Akt/mTOR/HIF-1α pathway. This study is expected to provide drug references and research ideas for the treatment of PH.

[Effect of Peitu Yifei Granules on autophagy mechanism in rats with idiopathic pulmonary fibrosis based on PI3K/Akt/mTOR signaling pathway].

To investigate the mechanism by which Peitu Yifei Granules inhibit idiopathic pulmonary fibrosis(IPF) in rats, fifty specific-pathogen-free(SPF) grade male Wistar rats were randomly divided into blank group and modeling group. IPF was induced in the modeling group rats by tracheal infusion of 5 mg·kg~(-1) bleomycin(BLM) and then randomly divided into model group, pirfenidone group, and high-dose, medium-dose, and low-dose groups treated with Peitu Yifei Granules. After 24 hours of modeling, the treatment groups received intragastric administration of either Peitu Yifei Granules or pirfenidone as a positive control drug; meanwhile, the model group received an equal volume of normal saline. After 21 days of treatment administration, lung tissue samples were collected for analysis. Pathological changes in lung tissues were assessed using hematoxylin-eosin(HE) staining and Masson's trichrome staining. The expression levels of protein kinase B(Akt), mammalian target of rapamycin(mTOR), their phosphorylated forms, and sequestosome 1(p62) were determined through Western blot(WB). Fluorescent quantitative real-time polymerase chain reaction(RT-qPCR) was used to measure messenger ribonucleic acid(mRNA) expression levels of Beclin-1, microtubule-associated proteins 1A/1B light chain 3B(LC3B), and p62. Immunohistochemistry was performed to assess protein expression levels of Beclin-1 and LC3B in lung tissue samples. RESULTS:: demonstrated that lung tissue structure appeared normal without significant collagen deposition in the blank group rats. In contrast, rats from the model group exhibited thickened alveolar septa along with evident inflammatory changes and collagen deposition. Compared to the model group rats, those treated with Peitu Yifei Granules or pirfenidone showed significantly improved lung tissue structure with reduced inflammation and collagen deposition observed histologically. Furthermore, compared with those of the blank group, the expressions of p62 and its mRNA, p-Akt and p-mTOR protein in lung tissues of the model group were significantly increased, while Beclin-1, LC3B and their mRNA levels were significantly decreased. Compared with those of the model group, the expressions of p62 and its mRNA, p-Akt and p-mTOR in lung tissues of the pirfenidone group and Peitu Yifei Granules high-dose and medium-dose groups were significantly decreased, while Beclin-1, LC3B and their mRNA expressions were significantly increased. The above results indicate that Peitu Yifei Granules can improve autophagy levels in lung tissues by inhibiting the phosphoinositide 3-kinase(PI3K)/Akt/mTOR signaling pathway and delay the development of IPF disease.

Relationships between endurance exercise training-induced muscle fiber-type shifting and autophagy in slow- and fast-twitch skeletal muscles of mice.

PURPOSE: Endurance exercise induces muscle fiber-type shifting and autophagy; however, the potential role of autophagy in muscle fiber-type transformation remains unclear. This study examined the relationship between muscle fiber-type shifting and autophagy in the soleus (SOL) and extensor digitorum longus (EDL) muscles, which are metabolically discrete muscles. METHODS: Male C57BL/6J mice were randomly assigned to sedentary control (CON) and exercise (EXE) groups. After 1 week of acclimation to treadmill running, the mice in the EXE group ran at 12-15 m/min, 60 min/day, 5 days/week for 6 weeks. All mice were sacrificed 90 min after the last exercise session, and the targeted tissues were rapidly dissected. The right side of the tissues was used for western blot analysis, whereas the left side was subjected to immunohistochemical analysis. RESULTS: Endurance exercise resulted in muscle fiber-type shifting (from type IIa to type I) and autophagy (an increase in LC3-II) in the SOL muscle. However, muscle fiber-type transformation and autophagy were not correlated in the SOL and EDL muscles. Interestingly, in contrast to the canonical autophagy signaling pathways, our study showed that exercise-induced autophagy concurs with enhanced anabolic (increased p-AKTSer473/AKT and p-mTOR/mTORSer2448 ratios) and suppressed catabolic (reduced p-AMPKThr172/AMPK ratio) states. CONCLUSION: Our findings demonstrate that chronic endurance exercise-induced muscle fiber-type transformation and autophagy occur in a muscle-specific manner (e.g., SOL). More importantly, our study suggests that endurance training-induced SOL muscle fiber-type transition may underlie metabolic modulations caused by the AMPK and AKT/mTOR signaling pathways rather than autophagy.

CTLA-4 expression on CD4+ lymphocytes in patients with sepsis-associated immunosuppression and its relationship to mTOR mediated autophagic-lysosomal disorder.

Background: The aim of this study was to clarify the relationship between expression level of CTLA-4 on CD4+ T cells and sepsis-associated immunosuppression (SAI), and to elucidate the possible mechanism of mTOR pathway mediated autophagic-lysosomal disorder in regulating CTLA-4 expression. Methods: We enrolled 63 sepsis patients admitted to our ICU between January 1 and June 30, 2023. Peripheral blood mononuclear cells were isolated from the patients within 24 hours of recruitment. Expression levels of mTOR, P62, LC3II, and CTLA-4 on circulating CD4+ T lymphocytes were quantitated using flow cytometry. The association of these markers and relationship between CTLA-4 expression and the incidence of SAI and 28-day mortality were comprehensively analyzed. Results: Compared with non-immunosuppressed patients with sepsis, patients with SAI had a higher 28-day mortality rate (37.5% vs 13.0%, P=0.039) and higher CTLA-4 mean fluorescence intensity (MFI) on CD4+ T cells (328.7 versus 78.7, P<0.0001). CTLA-4 MFI on CD4+ cells was independently associated with the occurrence of SAI (95% confidence interval: 1.00-1.14, P=0.044). In patients with sepsis and SAI, non-survivors had higher CTLA-4 expression than survivors (sepsis: 427.5 versus 130.6, P=0.002; and SAI: 506.7 versus 225.2, P<0.0001). The sensitivity and specificity of CTLA-4 MFI at predicting 28-day mortality in patients with SAI was 100% and 80% respectively with the cutoff value of 328.7 and the area under the curve of 0.949. The MFI of mTOR, P62, and LC3II on CD4+ T cells were statistically higher in patients with SAI than in non-immunosuppressed patients (267.2 versus 115.9, P<0.0001; 314.8 versus 173.7, P<0.0001; and 184.7 versus 1123.5, P=0.012, respectively); P62 and LC3II were markedly higher in non-survivors than in survivors of sepsis (302.9 versus 208.9, P=0.039; and 244.3 versus 122.8, P<0.0001 respectively). The expression of CTLA-4 statistically correlated with that of LC3II in patients with sepsis, patients with SAI, and patients with SAI who did not survive (correlation coefficient: 0.69, 0.68, and 0.73, respectively, P<0.0001). Conclusions: CTLA-4 overexpression on CD4+ T cells was markedly associated with the incidence of SAI and had great relevance to 28-day mortality. mTOR pathway mediated autophagic-lysosomal disorder showed significant association with CTLA-4 expression.

Integrating rapamycin with novel PI3K/Akt/mTOR inhibitor microRNAs on NOTCH1-driven T-cell acute lymphoblastic leukemia (T-ALL).

Introduction: The PI3K/AKT/mTOR signaling pathway plays a significant role in the development of T-cell acute lymphoblastic leukemia (T-ALL). Rapamycin is a potential therapeutic strategy for hematological malignancies due to its ability to suppress mTOR activity. Additionally, microRNAs (miRNAs) have emerged as key regulators in T-ALL pathophysiology and treatment. This study aimed to investigate the combined effects of rapamycin and miRNAs in inhibiting the PI3K/AKT/mTOR pathway in T-ALL cells. Methods: Bioinformatic algorithms were used to find miRNAs that inhibit the PI3K/AKT/mTOR pathway. Twenty-five bone marrow samples were collected from T-ALL patients, alongside five control bone marrow samples from non-leukemia patients. The Jurkat cell line was chosen as a representative model for T-ALL. Gene and miRNA expression levels were assessed using quantitative real-time PCR (qRT-PCR). Two miRNAs exhibiting down-regulation in both clinical samples and Jurkat cells were transfected to the Jurkat cell line to investigate their impact on target gene expression. Furthermore, in order to evaluate the potential of combination therapy involving miRNAs and rapamycin, apoptosis and cell cycle assays were carried out. Results: Six miRNAs (miR-3143, miR-3182, miR-99a/100, miR-155, miR-576-5p, and miR-501- 3p) were predicted as inhibitors of PI3K/AKT/mTOR pathway. The expression analysis of both clinical samples and the Jurkat cell line revealed a simultaneous downregulation of miR-3143 and miR-3182. Transfection investigation demonstrated that the exogenous overexpression of miR-3143 and miR-3182 can effectively inhibit PI3K/AKT/mTOR signaling in the Jurkat cell line. Moreover, when used as a dual inhibitor along with rapamycin, miR-3143 and miR-3182 significantly increased apoptosis and caused cell cycle arrest in the Jurkat cell line. Conclusion: These preliminary results highlight the potential for improving T-ALL treatment through multi-targeted therapeutic strategies involving rapamycin and miR-3143/miR-3182.

Chloride deregulation and GABA depolarization in MTOR related malformations of cortical development.

Focal Cortical Dysplasia, Hemimegalencephaly and Cortical Tuber are pediatric epileptogenic malformations of cortical development (MCDs) frequently pharmaco-resistant and mostly surgically treated by the resection of epileptic cortex. Availability of cortical resection samples allowed significant mechanistic discoveries directly from human material. Causal brain somatic or germline mutations in the AKT/PI3K/DEPDC5/MTOR genes were identified. GABAa mediated paradoxical depolarization, related to altered chloride (Cl-) homeostasis, was shown to participate to ictogenesis in human pediatric MCDs. However, the link between genomic alterations and neuronal hyperexcitability is still unclear. Here we studied the post translational interactions between the mTOR pathway and the regulation of cation-chloride cotransporters (CCC), KCC2 and NKCC1, that are largely responsible for controlling intracellular Cl- and ultimately GABAergic transmission. For this study, 35 children (25 MTORopathies and 10 pseudo controls, diagnosed by histology plus genetic profiling) were operated for drug resistant epilepsy. Postoperative cortical tissues were recorded on multielectrode array (MEA) to map epileptic activities. CCC expression level and phosphorylation status of the WNK1/SPAK-OSR1 pathway was measured during basal conditions and after pharmacological modulation. Direct interactions between mTOR and WNK1 pathway components were investigated by immunoprecipitation. Membranous incorporation of MCD samples in Xenopus laevis oocytes enabled Cl- conductance and equilibrium potential (EGABA) for GABA measurement. Of the 25 clinical cases, half harbored a somatic mutation in the mTOR pathway, while pS6 expression was increased in all MCD samples. Spontaneous interictal discharges were recorded in 65% of the slices. CCC expression was altered in MCDs, with a reduced KCC2/NKCC1 ratio and decreased KCC2 membranous expression. CCC expression was regulated by the WNK1/SPAK-OSR1 kinases through direct phosphorylation of Thr906 on KCC2, that was reversed by WNK1 and SPAK antagonists (NEM and Staurosporine). mSIN1 subunit of MTORC2 was found to interact with SPAK-OSR1 and WNK1. Interactions between these key epileptogenic pathways could be reversed by the mTOR specific antagonist Rapamycin, leading to a dephosphorylation of CCCs and recovery of the KCC2/NKCC1 ratio. The functional effect of such recovery was validated by the restoration of the depolarizing shift in EGABA by rapamycin, measured after incorporation of MCD membranes to X. laevis oocytes, in line with a reestablishment of normal ECl-. Our study deciphers a protein interaction network through a phosphorylation cascade between MTOR and WNK1/SPAK-OSR1 leading to chloride cotransporters deregulation, increased neuronal chloride levels and GABAa dysfunction in malformations of Cortical Development, linking genomic defects and functional effects and paving the way to target epilepsy therapy.

Clinical Outcomes and Targeted Genomic Analysis of Renal Cell Carcinoma Brain Metastases Treated with Stereotactic Radiosurgery.

BACKGROUND: Molecular profiles of renal cell carcinoma (RCC) brain metastases (BMs) are not well characterized. Effective management with locoregional therapies, including stereotactic radiosurgery (SRS), is critical as systemic therapy advancements have improved overall survival (OS). OBJECTIVE: To identify clinicogenomic features of RCC BMs treated with SRS in a large patient cohort. DESIGN, SETTING, AND PARTICIPANTS: A single-institution retrospective analysis was conducted of all RCC BM patients treated with SRS from January 1, 2010 to March 31, 2021. INTERVENTION: SRS for RCC BMs. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Next-generation sequencing was performed to identify gene alterations more prevalent in BM patients. Clinical factors and genes altered in ≥10% of samples were assessed per patient using Cox proportional hazards models and per individual BM using clustered competing risks regression with competing risk of death. RESULTS AND LIMITATIONS: Ninety-one RCC BM patients underwent SRS to 212 BMs, with a median follow-up of 38.8 mo for patients who survived. The median intracranial progression-free survival and OS were 7.8 (interquartile range [IQR] 5.7-11) and 21 (IQR 16-32) mo, respectively. Durable local control of 83% was achieved at 12 mo after SRS, and 59% of lesions initially meeting the radiographic criteria for progression at 3-mo evaluation would be considered to represent pseudoprogression at 6-mo evaluation. A comparison of genomic alterations at both the gene and the pathway level for BM+ patients compared with BM- patients revealed phosphoinositide 3-kinase (PI3K) pathway alterations to be more prevalent in BM+ patients (43% vs 16%, p = 0.001, q = 0.01), with the majority being PTEN alterations (17% vs 2.7%, p = 0.003, q = 0.041). CONCLUSIONS: To our knowledge, this is the largest study investigating genomic profiles of RCC BMs and the only such study with annotated intracranial outcomes. SRS provides durable in-field local control of BMs. Recognizing post-SRS pseudoprogression is crucial to ensure appropriate management. The incidence of PI3K pathway alterations is more prevalent in BM+ patients than in BM- patients and warrants further investigation in a prospective setting. PATIENT SUMMARY: We examined the outcomes of radiotherapy for the treatment of brain metastases in kidney cancer patients at a single large referral center. We found that radiation provides good control of brain tumors, and certain genetic mutations may be found more commonly in patients with brain metastasis.

A refined formula derived from Jiawei-Xiaoyao pill exerts rapid antidepressant-like effects in LPS-induced depression by reducing neuroinflammation and restoring neuroplasticity signaling.

ETHNOPHARMACOLOGICAL RELEVANCE: Jiawei-Xiaoyao Pill (JWX), a classic formula in traditional Chinese medicine, is derived from Xiaoyao Pill by adding significant amounts of Gardeniae Fructus (GF) and Moutan Cortex (MC). It is frequently used for the treatment of depression. JWX has been demonstrated to uniquely elicit rapid antidepressant-like effects within the prescribed dosage range. To date, GF has been shown to have rapid antidepressant-like effects, but a much higher dose is required than its proportion in JWX. It is assumed that the synergism of GF with a minimum number of other herbs in JWX serves as a refined formula that exerts these rapid antidepressant-like effects. Identification of a refined formula is important for prioritizing the herbs and ingredients to optimize the quality control of JWX. However, such a refined formula for JWX has not been identified yet. AIM OF THE STUDY: Here we aimed to identify a refined formula derived from JWX for optimized rapid antidepressant-like effects. Since the neuroinflammation mechanism involving in depression treatment has not been previously investigated for JWX, we tested the mechanism for both JWX and the refined formula. MATERIALS AND METHODS: Individual herbs (MC; ASR, Angelica Sinensis Radix; Bupleuri Radix; Paeonia Radix Alba) that show antidepressant-like responses were mixed with GF at the proportional dosage in JWX to identify the refined formula. Rapid antidepressant-like effects were assessed by using NSF (Novelty Suppressed Feeding Test) and other behavioral tests following a single administration. The identified formula was further tested in a lipopolysaccharide (LPS)-induced depressive model, and the molecular signaling mechanisms were investigated using Western blot analysis, immunofluorescence, and pharmacological inhibition of mTOR signaling. Scopolamine (Scop) was used as a positive control for induction of rapid antidepressant effects. RESULTS: A combination of GF, MC and ASR (GMA) at their dosages proportional to JWX induced behavioral signs of rapid antidepressant-like responses in both normal and LPS-treated mice, with the antidepressant-like effects sustained for 5 d. Similar to JWX or Scop, GMA rapidly reduced the neuroinflammation signaling of Iba-1-NF-кB, enhanced neuroplasticity signaling of CaMKII-mTOR-BDNF, and attenuated the upregulated expressions of the NMDAR sub-units GluN1 and GluN2B in the hippocampus of LPS-treated mice. GMA, JWX and Scop rapidly restored the number of BDNF-positive cells reduced by LPS treatment in the CA3 region of the hippocampus. Furthermore, rapamycin, a selective inhibitor of mTOR, blunted the rapid antidepressant-like effects and hippocampal BDNF signaling upregulation by GMA. CONCLUSION: GMA may serve as a refined formula from JWX, capable of inducing rapid antidepressant-like effects. In the LPS-induced depression model, the effects of GMA were mediated via rapidly alleviating neuroinflammation and enhancing neuroplasticity.

A Perspective of PI3K/AKT/mTOR Pathway Inhibitors to Overcome Drug-resistance in Breast Cancer Therapy.

The heterogeneous disease, breast cancer (BC), is a frequently detected cancer today, including hormone receptor-positive (HR+), human epidermal growth factor receptor-2-positive (HER2+), and triple-negative (ER-, PR-, HER2-) BC. Advanced endocrine therapies could improve about 85% HR+ BC patient survival. Still, 20% - 30% of cases of endocrine therapy resistance are observed. For all kinds of breast cancer, drug resistance is a common and dangerous phenomenon, comprised of two types: de novo resistance and acquired resistance (prolonged exposure). According to recent works of literature, the PI3K/AKT/mTOR pathway has become an emerging target for overcoming drug resistance in BC therapy due to its close association with tumour growth and resistance from current therapies. Activation of the PI3K/AKT/mTOR pathway was found to promote multidrug resistance by elevating drugs' outflow. The first orally active PI3K inhibitor, Alpelisib (BYL-719) in fulvestrant combination, was approved for treating HR+/ HER2- metastatic BC. Therefore, utilizing PI3K/mTOR/AKT inhibitors in combination with currently available strategies could be an optimistic approach to overcoming drug resistance and resensitizing drug-resistant tumor cells of BC. Here, in this perspective, BC cancer therapies related to drug resistance, the involvement of PI3K/AKT/mTOR pathway in drug resistance and multi-drug resistance, and the role of PI3K/AKT/mTOR inhibitors in getting rid of drug resistance have been illuminated.

mTORC1 mediates the expansion of hematopoietic stem and progenitor cells through ribosome biogenesis protein Urb2 in zebrafish.

Mammalian target of rapamycin (mTOR) serves as the key sensor to control protein synthesis, cell growth, and survival. Despite mTOR is reported to regulate hematopoietic stem and progenitor cell (HSPC) engraftment and multiple-lineage hematopoiesis in mice, the roles of unique mTOR complexes (mTORCs) in early HSPC development and HSPC pool formation have not been adequately elucidated. Here, we uncover that mTORC1 is essential for early HSPC expansion in zebrafish. mTORC1 signaling was highly activated in definitive HSPCs during the emerging and expanding stages. Pharmacological or genetic inactivation of mTORC1 would cause defective HSPC expansion and migration due to disrupted cell proliferation. Interestingly, mTORC2 is dispensable for early HSPC development. Ribosome biogenesis protein Urb2 was downregulated upon mTORC1 inhibition, and urb2 overexpression partially rescued the hematopoietic defects in mTORC1-deficient embryos. These data demonstrate that mTORC1 signaling regulates early HSPC expansion through Urb2, and this work will deepen our understanding of mTOR in different physiological processes.

Spontaneous Hydropneumothorax After Pleurodesis in a Patient With Pulmonary Lymphangioleiomyomatosis With Associated Endometrial Cancer.

Lymphangioleiomyomatosis (LAM) is a rare cystic disease that occurs due to the abnormal proliferation of smooth muscle-like cells. It primarily affects the lungs but can also have extrapulmonary manifestations such as lymphangioleiomyoma and angiomyolipomas. It is more common in young women of childbearing age, with female sex hormones contributing to the disease course. LAM can develop either through sporadic mutations or through genetic inheritance of the tuberous sclerosis complex (TSC) genes. TSC, LAM, and endometrial cancer are associated with mTOR pathway activation, which can explain why these diseases can co-exist, although the co-existence of LAM and endometrial cancer in the same patient is very rare. Due to the cystic nature of LAM, pneumothorax most often occurs at least once during the course of the disease, and most times, it is the first manifestation observed in LAM. These patients are also at high risk for recurrent pneumothorax, and when that occurs, pleurodesis is indicated. Unfortunately, pleurodesis still does not preclude a pneumothorax from occurring. We present the case of a female patient with LAM and endometrial cancer who was found to have an incidental spontaneous hydropneumothorax after pleurodesis. Patients with LAM should be closely monitored for the possible development of other mTOR-associated diseases. Moreover, when performing pleurodesis for recurrent pneumothorax in very high-risk patients, the procedure with the lowest recurrence rate should be utilized.

Update on non-infectious uveitis treatment: anti-TNF-alpha and beyond.

Non-infectious uveitis (NIU) encompasses a range of conditions marked by inflammation within various layers of the eye. NIU is a significant contributor to irreversible vision loss among the working-age population in developed countries. The aim of treating uveitis is to manage inflammation, prevent its recurrences and to restore or salvage vision. Presently, the standard treatment protocol for NIU involves initiating corticosteroids as the primary therapeutic agents, although more aggressive approaches and steroid sparing agent may be necessary in certain cases. These advanced treatments option include synthetic immunosuppressants like antimetabolites, calcineurin inhibitors and alkylating agents. For patients who exhibit an intolerance or resistance to corticosteroids and conventional immunosuppressive therapies, biologic agents have emerged as a promising alternative. Notably, among the biologic treatments evaluated, TNF-α inhibitors, anti-CD20 therapy and alkylating agents have shown considerable efficacy. In this review, we delve into the latest evidence surrounding the effectiveness of biologic therapy and introduce novel therapeutic strategies targeting immune components as potential avenues for advancing treatment of NIU.