Ubiquitination at the lysine 27 residue of the Parkin ubiquitin-like domain is suggestive of a new mechanism of Parkin activation.

The mitochondrial kinase PTEN-induced kinase 1 (PINK1) and cytosolic ubiquitin ligase (E3) Parkin/PRKN are involved in mitochondrial quality control responses. PINK1 phosphorylates ubiquitin and the Parkin ubiquitin-like (Ubl) domain at serine 65 and promotes Parkin activation and translocation to damaged mitochondria. Upon Parkin activation, the Ubl domain is ubiquitinated at lysine (K) 27 and K48 residues. However, the contribution of K27/K48 ubiquitination toward Parkin activity remains unclear. In this study, ubiquitination of K56 (corresponding to K27 in the human), K77 (K48 in the human) or both was blocked by generating Drosophila Parkin (dParkin) mutants to examine the effects of Parkin Ubl domain ubiquitination on Parkin activation in Drosophila. The dParkin, in which K56 was replaced with arginine (dParkin K56R), rescued pupal lethality in flies by co-expression with PINK1, whereas dParkin K77R could not. The dParkin K56R exhibited reduced abilities of mitochondrial fragmentation and motility arrest, which are mediated by degrading Parkin E3 substrates Mitofusin and Miro, respectively. Pathogenic dParkin K56N, unlike dParkin K56R, destabilized the protein, suggesting that not only was dParkin K56N non-ubiquitin-modified at K56, but also the structure of the Ubl domain for activation was largely affected. Ubiquitin attached to K27 of the Ubl domain during PINK1-mediated Parkin activation was likely to be phosphorylated because human Parkin K27R weakened Parkin self-binding and activation in trans. Therefore, our findings suggest a new mechanism of Parkin activation, where an activation complex is formed through phospho-ubiquitin attachment on the K27 residue of the Parkin Ubl domain.

Super-enhancer-controlled positive feedback loop BRD4/ERα-RET-ERα promotes ERα-positive breast cancer.

Estrogen and estrogen receptor alpha (ERα)-induced gene transcription is tightly associated with ERα-positive breast carcinogenesis. ERα-occupied enhancers, particularly super-enhancers, have been suggested to play a vital role in regulating such transcriptional events. However, the landscape of ERα-occupied super-enhancers (ERSEs) as well as key ERα-induced target genes associated with ERSEs remain to be fully characterized. Here, we defined the landscape of ERSEs in ERα-positive breast cancer cell lines, and demonstrated that bromodomain protein BRD4 is a master regulator of the transcriptional activation of ERSEs and cognate ERα target genes. RET, a member of the tyrosine protein kinase family of proteins, was identified to be a key ERα target gene of BRD4-regulated ERSEs, which, in turn, is vital for ERα-induced gene transcriptional activation and malignant phenotypes through activating the RAS/RAF/MEK2/ERK/p90RSK/ERα phosphorylation cascade. Combination therapy with BRD4 and RET inhibitors exhibited additive effects on suppressing ERα-positive breast cancer both in vitro and in vivo, comparable with that of standard endocrine therapy tamoxifen. Furthermore, combination therapy re-sensitized a tamoxifen-resistant ERα-positive breast cancer cell line to tamoxifen treatment. Taken together, our data uncovered the critical role of a super-enhancer-associated positive feedback loop constituting BRD4/ERα-RET-ERα in ERα-positive breast cancer, and suggested that targeting components in this loop would provide a new therapeutic avenue for treating ERα-positive breast cancer in the clinic.

Role of α-synuclein in microglia: autophagy and phagocytosis balance neuroinflammation in Parkinson's disease.

BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disease, and is characterized by accumulation of α-synuclein (α-syn). Neuroinflammation driven by microglia is an important pathological manifestation of PD. α-Syn is a crucial marker of PD, and its accumulation leads to microglia M1-like phenotype polarization, activation of NLRP3 inflammasomes, and impaired autophagy and phagocytosis in microglia. Autophagy of microglia is related to degradation of α-syn and NLRP3 inflammasome blockage to relieve neuroinflammation. Microglial autophagy and phagocytosis of released α-syn or fragments from apoptotic neurons maintain homeostasis in the brain. A variety of PD-related genes such as LRRK2, GBA and DJ-1 also contribute to this stability process. OBJECTIVES: Further studies are needed to determine how α-syn works in microglia. METHODS: A keyword-based search was performed using the PubMed database for published articles. CONCLUSION: In this review, we discuss the interaction between microglia and α-syn in PD pathogenesis and the possible mechanism of microglial autophagy and phagocytosis in α-syn clearance and inhibition of neuroinflammation. This may provide a novel insight into treatment of PD.

BRD4 inhibition boosts the therapeutic effects of epidermal growth factor receptor-targeted chimeric antigen receptor T cells in glioblastoma.

Glioblastoma (GBM) is the deadliest brain malignancy without effective treatments. Here, we reported that epidermal growth factor receptor-targeted chimeric antigen receptor T cells (EGFR CAR-T) were effective in suppressing the growth of GBM cells in vitro and xenografts derived from GBM cell lines and patients in mice. However, mice soon acquired resistance to EGFR CAR-T cell treatment, limiting its potential use in the clinic. To find ways to improve the efficacy of EGFR CAR-T cells, we performed genomics and transcriptomics analysis for GBM cells incubated with EGFR CAR-T cells and found that a large cohort of genes, including immunosuppressive genes, as well as enhancers in vicinity are activated. BRD4, an epigenetic modulator functioning on both promoters and enhancers, was required for the activation of these immunosuppressive genes. Accordingly, inhibition of BRD4 by JQ1 blocked the activation of these immunosuppressive genes. Combination therapy with EGFR CAR-T cells and JQ1 suppressed the growth and metastasis of GBM cells and prolonged survival in mice. We demonstrated that transcriptional modulation by targeting epigenetic regulators could improve the efficacy of immunotherapy including CAR-T, providing a therapeutic avenue for treating GBM in the clinic.

LDHA Suppression Altering Metabolism Inhibits Tumor Progress by an Organic Arsenical.

Based on the potential therapeutic value in targeting metabolism for the treatment of cancer, an organic arsenical PDT-BIPA was fabricated, which exerted selective anti-cancer activity in vitro and in vivo via targeting lactate dehydrogenase A (LDHA) to remodel the metabolic pathway. In details, the precursor PDT-BIPA directly inhibited the function of LDHA and converted the glycolysis to oxidative phosphorylation causing ROS burst and mitochondrial dysfunction. PDT-BIPA also altered several gene expression, such as HIF-1α and C-myc, to support the metabolic remodeling. All these changes lead to caspase family-dependent cell apoptosis in vivo and in vitro without obvious side effect. Our results provided this organic arsenical precursor as a promising anticancer candidate and suggested metabolism as a target for cancer therapies.

Effects of crystalline state and self-nanoemulsifying drug delivery system (SNEDDS) on oral bioavailability of the novel anti-HIV compound 6-benzyl-1-benzyloxymethyl-5-iodouracil in rats.

The objective of this study was to investigate the effect of crystalline state and a formulation of self-nanoemulsifying drug delivery system (SNEDDS) on oral bioavailability of 6-benzyl-1-benzyloxymethyl-5-iodouracil (W-1), a novel non-nucleoside reverse transcriptase inhibitor, in rats. The crystalline states of W-1 were characterized by scanning electron microscope (SEM), differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD). The SNEDDS was formulated by medium-chain lipids, characterized by droplet particle size. The plasma concentrations of W-1 were measured by high performance liquid chromatography (HPLC). The results indicated that W-1 compound were presented as crystalline forms, A and B, the degree of crystallization in form B was higher than that in form A. The SNEDDS of W-1 displayed a significant increase in the dissolution rate than W-1 powder. Furthermore, after oral administration of W-1 (100 mg/kg), the pharmacokinetic parameters of form A, form B, and W-1 SNEDDS were as follows: AUC0-t 526.4 ± 123.5, 305.1 ± 58.5 and 2297 ± 451 ng h/mL (p < .05, when W-1 SNEDDS were compared with either form A or form B), respectively. With SNEDDS formulation, the relative bioavailabilities were enhanced by 4.36-fold and 7.53-fold over the form A and form B of W-1, respectively. In conclusion, the present results suggested that the crystalline states of W-1 might lead to the lower oral bioavailability, and SNEDDS formulation is a promising strategy of improving bioavailability, in spite of that crystalline states usually carry small lot-to-lot variability.

Pain Correlates with Sleep Disturbances in Parkinson's Disease Patients.

OBJECTIVES: Both sleep disorders and pain decrease quality of life in patients with Parkinson's disease (PD). However, little is known about the relationship between objective sleep disturbances and pain in patients with PD. This study aimed to (1) examine the clinical characteristics of pain in PD patients and (2) explore the correlation between pain and sleep disturbances in PD patients. METHODS: Parkinson's disease patients (N = 144) underwent extensive clinical evaluations of motor and nonmotor symptoms and characteristics of pain. Overnight video-polysomnography was also conducted. Clinical characteristics and sleep parameters were compared between PD patients with or without pain. RESULTS: Pain was reported by 75 patients (52.1%), with 49 (65.3%) reporting pain of at least moderate severity. PD patients with pain were older and had longer disease duration, more severe PD symptoms as assessed by Hoehn and Yahr stage and the Unified Parkinson's Disease Rating Scale, and higher L-dopa equivalent daily dose compared with PD patients without pain. PD patients with pain also showed significantly decreased sleep efficiency (57.06% ± 15.84% vs. 73.80% ± 12.00%, P < 0.001), increased nonrapid eye movement stage 1 (N1) sleep (33.38% ± 19.32% vs. 17.84% ± 8.48%, P < 0.001), and decreased rapid eye movement sleep (12.76% ± 8.24% vs. 16.06% ± 6.53%, P = 0.009). Binary logistic regression analysis revealed that poorer activities of daily living, depressed mood, higher percentage of N1 sleep, and lower sleep efficiency were independent predictors of pain in patients with PD. CONCLUSIONS: Musculoskeletal pain is the most common type of pain in patients with PD. Disrupted sleep continuity, altered sleep architecture, depressed mood, and compromised activities of daily living may be associated with pain in patients with PD.

Roles of ST2, IL-33 and BNP in predicting major adverse cardiovascular events in acute myocardial infarction after percutaneous coronary intervention.

This study investigated roles of serum ST2, IL-33 and BNP in predicting major adverse cardiovascular events (MACEs) in acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI). Blood samples were collected from the included AMI patients (n = 180) who underwent PCI. All patients were divided into the MACEs and MACEs-free groups. Enzyme-linked immunosorbent assay was performed to measure serum levels of ST2, IL-33 and BNP. Severity of coronary artery lesion was evaluated by Gensini score. Pearson correlation analysis was used. A receiver operating characteristics curve was drawn to evaluate the potential roles of ST2, IL-33 and BNP in predicting MACEs, and Kaplan-Meier curve to analyse the 1-year overall survival rate. Logistic regression analysis was conducted to analyse the independent risk factors for MACEs. Compared with the MACEs-free group, the serum levels of ST2, IL-33 and BNP were significantly higher in the MACEs group. Serum levels of ST2, IL-33 and BNP were positively correlated with each other and positively correlated with Gensini score. The area under curves of ST2, IL-33 and BNP, respectively, were 0.872, 0.675 and 0.902. The relative sensitivity and specificity were, respectively, 76.27% and 85.92%, 69.49% and 58.68%, as well as, 96.61% and 77.69%. Serum levels of ST2, IL-33 and BNP were independent risk factors for MACEs. The 1-year overall survival rate was higher in AMI patients with lower serum levels of ST2, IL-33 and BNP. In conclusion, serum levels of ST2, IL-33 and BNP have potential value in predicting MACEs in AMI patients undergoing PCI.

Attenuation of hyperalgesia responses via the modulation of 5-hydroxytryptamine signalings in the rostral ventromedial medulla and spinal cord in a 6-hydroxydopamine-induced rat model of Parkinson's disease.

Background Although pain is one of the most distressing non-motor symptoms among patients with Parkinson's disease, the underlying mechanisms of pain in Parkinson's disease remain elusive. The aim of the present study was to investigate the role of serotonin (5-hydroxytryptamine) in the rostral ventromedial medulla (RVM) and spinal cord in pain sensory abnormalities in a 6-hydroxydopamine-treated rat model of Parkinson's disease. Methods The rotarod test was used to evaluate motor function. The radiant heat test and von Frey test were conducted to evaluate thermal and mechanical pain thresholds, respectively. Immunofluorescence was used to examine 5-hydroxytryptamine neurons and fibers in the rostral ventromedial medulla and spinal cord. High-performance liquid chromatography was used to determine 5-hydroxytryptamine and 5-hydroxyindoleacetic acid levels. Results The duration of running time on the rotarod test was significantly reduced in 6-hydroxydopamine-treated rats. Nociceptive thresholds of both mechanical and heat pain were reduced compared to sham-treated rats. In addition to the degeneration of cell bodies and fibers in the substantia nigra pars compacta, the number of rostral ventromedial medulla 5-hydroxytryptamine neurons and 5-hydroxytryptamine fibers in the spinal dorsal horn was dramatically decreased. 5-Hydroxytryptamine concentrations in both the rostral ventromedial medulla and spinal cord were reduced. Furthermore, the administration of citalopram significantly attenuated pain hypersensitivity. Interestingly, Intra-rostral ventromedial medulla (intra-RVM) microinjection of 5,7-dihydroxytryptamine partially reversed pain hypersensitivity of 6-hydroxydopamine-treated rats. Conclusions These results suggest that the decreased 5-hydroxytryptamine contents in the rostral ventromedial medulla and spinal dorsal horn may be involved in hyperalgesia in the 6-hydroxydopamine-induced rat model of Parkinson's disease.

Identification of cytochrome P450s involved in the metabolism of 6-benzyl-1-benzyloxymethyl-5-iodouracil (W-1) using human recombinant enzymes and rat liver microsomes in vitro.

1. The aim of this study was to identify the hepatic metabolic enzymes, which involved in the biotransformation of 6-benzyl-1-benzyloxymethyl-5-iodouracil (W-1), a novel non-nucleoside reverse transcriptase inhibitor (NNRTI) in rat and human in vitro. 2. The parent drug of W-1 was incubated with rat liver microsomes (RLMs) or recombinant CYPs (CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4, and CYP3A5, respectively) in the presence or absence of nicotinamide adeninedinucleotide phosphate (NADPH)-regenerating system. The metabolites of W-1 were analyzed with liquid chromatography-ion trap-time of flight-mass spectrometry (LC-IT-TOF-MS). 3. The parent drug of W-1 was metabolized in a NADPH-dependent manner in RLMs. The kinetic parameters of prototype W-1 including Km, Vmax, and CLint were 2.3 µM, 3.3 nmol/min/mg protein, and 1.4 mL/min/mg protein, respectively. Two metabolites M1 and M2 were observed in shorter retention times (2.988 and 3.188 min) with a higher molecular ion at m/z 463.0160 (both M1 and M2) than that of the W-1 parent drug (6.158 min with m/z 447.0218). The CYP selective inhibition and recombinant enzymes also showed that two hydroxyl metabolites M1 and M2 are mainly mediated by CYP2C19 and CYP3A4. 4. The identification of CYPs involved in W-1 biotransformation is important to understand and minimize, if possible, the potential of drug-drug interactions.

Retinal nerve fiber layer thinning: a window into rapid eye movement sleep behavior disorders in Parkinson's disease.

PURPOSE: Retinal nerve fiber layer (RNFL) thinning occurs in Parkinson's disease (PD) and other neurodegenerative diseases. Idiopathic RBD (iRBD) is a well-established prodromal hallmark of synucleinopathies and occurs secondary to many neurodegenerative diseases, including PD. The aim of this study is to determine whether or not retinal structures are altered with the onset of rapid eye movement (REM) sleep behavior disorders (RBD). METHODS: In all, a total of 63 patients with PD, 14 patients with idiopathic RBD, and 26 sex- and age-matched healthy controls were enrolled and underwent optical coherence tomography measurements (HD-OCT (Zeiss) ) for the average and every quadrant of RNFL thickness. The REM Sleep Behavior Disorder Screening Questionnaire (RBDSQ) was used to classify PD patients with clinically probable RBD (PD + pRBD) or without probable RBD (PD - pRBD). Patients with iRBD were identified by polysomnography. RESULTS: For patients with RBD (idiopathic or secondary to PD), we found a significant decrease in RNFL thickness compared with groups without RBD (PD - pRBD and healthy controls) (all p < 0.05). Average RNFL thickness in patients with iRBD is significantly thinner than in healthy controls (p < 0.05). In PD, the average RNFL thickness was dramatically thinner in the PD + pRBD group than the PD - pRBD group (p < 0.005). Compared with healthy controls, RNFL thickness was slightly thinner in the drug-naive PD group but not the PD group with drug treatment. Multiple linear regression analysis showed that RBDSQ score was negatively associated with average and inferior RNFL variation in PD (all p < 0.005). CONCLUSIONS: The findings show that RNFL was slightly but significantly thinner in idiopathic RBD. In PD, RNFL thickness may vary depending on the presence of RBD.

Development and validation of a high performance liquid chromatography method for determination of 6-benzyl-1-benzyloxymethyl-5-iodouracil (W-1), a novel non-nucleoside reverse transcriptase inhibitor and its application to a pharmacokinetic study in rats.

A sensitive and selective high-performance liquid chromatographic (HPLC) method for determination of 6-benzyl-1-benzyloxymethyl-5-iodouracil (W-1), a novel non-nucleoside reverse transcriptase inhibitor in rat plasma, was developed and validated. Chromatographic separation of W-1 and megestrol acetate (internal standard) was achieved on a reversed-phase C18 column at 25°C. The mobile phase was consisted of acetonitrile-water (60:40, v/v) and pumped at a flow rate of 1.0 mL/min. The ultraviolet (UV) detector was set at the absorption wavelength of 284 nm. The calibration curve for W-1 was linear over the concentration range of 0.01-8 µg/mL and the lower limit of quantification was 10 ng/mL. The intra- and inter-day precision and accuracy were <8.9 and 5.3%, respectively. The extraction recoveries ranged from 97.9 to 101.6%. The validated HPLC method was successfully applied to a pharmacokinetic study of W-1 in rats.

[Synthesis of 6-benzyl-1-[(benzyloxy)methyl]-3-hydroxy-5-(hydroxymethyl)pyrimidine-2,4(1H,3H)-dione].

OBJECTIVE: To find the best synthesis method of 6-benzyl-1-[(benzyloxy)methyl]-3-hydroxy-5-(hydroxymethyl) pyrimidine-2,4(1H,3H)-dione e for observing the change of its biological activity after N-3 hydroxylation. METHODS: After trying some N-hydroxylation methods, the target compound was successfully synthesized via one-pot oxidizing process by sodium hydride (NaH) and 3-chloroperbenzoic acid(m-CPBA); the anti-HIV reverse transcriptase (RT) activity and integrase (IN) activity of the target compound was assayed via enzyme-linked immunesorbent assay (ELISA) and phosphorylation of DNA package method. RESULTS: The target compound could be obtained through the improved m-CPBA oxidative method by only one step, and the yield of the reaction could reach 60%-70%. And the structure of this compound was identified by 1H NMR, 13C NMR and MS; The activity result showed it added the anti-HIV IN activity after N-3 hydroxylation as well as retained the anti-HIV RT activity. CONCLUSION: The improved m-CPBA oxidative method is a convenient and efficient way to prepare the compound 6-benzyl-1-[(benzyloxy)methyl]-3-hydroxy-5-(hydroxymethyl)pyrimidine-2,4(1H,3H)-dione e which has both anti-HIV RT and IN activity.

[Improved synthesis process of diethyl N-[4-[(2,4-diaminopyrido[3,2-d]pyrimidin-6-yl)methylamino]benzoyl]-L-glutamate].

OBJECTIVE: To establish a new approach to synthesis of diethyl N-[4-[(2,4-diaminopyrido[3,2-d]pyrimidin-6-yl)methylamino]benzoyl]-L-glutamate. METHODS: Target compound (5) was synthesized by the use of (2,4-dioxo-tetrahydropyridopyrimidin-6-yl)methyl acetate (1) as starting material via hydrolysis, chlorination, condensation with diethyl (p-aminobenzoyl)glutamate and aminolysis. RESULTS: A new approach to synthesis of diethyl N-[4-[(2,4-diaminopyrido[3,2-d]pyrimidin-6-yl)methylamino]benzoyl]-L-glutamate was established. This synthetic route has hydrolysis reaction, chlorination, diethyl N-(p-aminobenzoyl)-L-glutamate condensation reaction and ammonolysis reaction. The total yield is 36.7%.The structures of those compounds have identified by 1H nuclear magnetic resonance, 13C nuclear magnetic resonance and mass spectrometry. This synthetic route avoid the unstable brominated reaction product and improves the harsh condition of ammonolysis reaction. CONCLUSION: The new synthetic route has improved the reaction condition and the stability of the intermediate, and increased the extent of the derivative compounds, which has great significance to anti-folic acid of anti-tumor inhibitor synthesis.

[Identification of major components of Xingsusan decoction by HPLC-HR-TOF/MS].

OBJECTIVE: The major components of Xingsusan decoction were studied by HPLC-HR-TOF-MS. METHODS: A Welchrom- C18 column (4.6 mm x 250 mm, 5 µm) was used at a flow rate of 1.0 mL/min. The HPLC gradient was acetonitrile-formic acid (99.9: 0.1, V/V) (B) and water-formic acid (99.9:0.1, V/V) (A). HR-MS/MS analysis were carried out using a Micro/TOF-Q II Focus mass spectrometer fitted with an ESI source operating in Auto-MSn mode to obtain fragment ions. TIC chemical profiles of the extract were established in both positive and negative modes. The structures of the known components in Xingsusan decoction were identified by comparing their retention times, molecular weight and CID fragmentation patterns with their corresponding compounds reported in the literature. RESULTS: A total of 52 components were simultaneously detected in Q-TOF/MS. CONCLUSION: This method can be used as reference for other Chinese Medicine formulas study.

Relationship Between Short-chain Fatty Acids and Parkinson's Disease: A Review from Pathology to Clinic.

Parkinson's disease (PD) is a complicated neurodegenerative disease, characterized by the accumulation of α-synuclein (α-syn) in Lewy bodies and neurites, and massive loss of midbrain dopamine neurons. Increasing evidence suggests that gut microbiota and microbial metabolites are involved in the development of PD. Among these, short-chain fatty acids (SCFAs), the most abundant microbial metabolites, have been proven to play a key role in brain-gut communication. In this review, we analyze the role of SCFAs in the pathology of PD from multiple dimensions and summarize the alterations of SCFAs in PD patients as well as their correlation with motor and non-motor symptoms. Future research should focus on further elucidating the role of SCFAs in neuroinflammation, as well as developing novel strategies employing SCFAs and their derivatives to treat PD.

Effects of sleep fragmentation on white matter pathology in a rat model of cerebral small vessel disease.

STUDY OBJECTIVES: Mounting evidence indicated the correlation between sleep and cerebral small vessel disease (CSVD). However, little is known about the exact causality between poor sleep and white matter injury, a typical signature of CSVD, as well as the underlying mechanisms. METHODS: Spontaneously hypertensive rats (SHR) and control Wistar Kyoto rats were subjected to sleep fragmentation (SF) for 16 weeks. The effects of chronic sleep disruption on the deep white matter and cognitive performance were observed. RESULTS: SHR were validated as a rat model for CSVD. Fragmented sleep induced strain-dependent white matter abnormalities, characterized by reduced myelin integrity, impaired oligodendrocytes precursor cells (OPC) maturation and pro-inflammatory microglial polarization. Partially reversible phenotypes of OPC and microglia were observed in parallel following sleep recovery. CONCLUSIONS: Long-term SF-induced pathological effects on the deep white matter in a rat model of CSVD. The pro-inflammatory microglial activation and the block of OPC maturation may be involved in the mechanisms linking sleep to white matter injury.

α-Synuclein-Induced Destabilized BMAL1 mRNA Leads to Circadian Rhythm Disruption in Parkinson's Disease.

Circadian dysfunction is a common non-motor symptom in Parkinson's disease (PD). The potential influence of aggravated α-synuclein (SNCA) on circadian disruption remains unclear. SNCAA53T-overexpressing transgenic mice (SNCAA53T mice) and wild-type (WT) littermates were used in this study. The energy metabolism cage test showed differences in 24-h activity pattern between SNCAA53T and WT mice. When compared with the age-matched littermates, brain and muscle ARNT-like 1 (BMAL1) was downregulated in SNCAA53T mice. BMAL1 was downregulated in PC12 cells overexpressing SNCA. Degradation of BMAL1 protein remained unchanged after overexpression of SNCA, while its mRNA level decreased. miRNA (miR)-155 was upregulated by overexpression of SNCA, and downregulation of BMAL1 was partially reversed by transfection with miR-155 inhibitor. Our findings demonstrated that overexpression of SNCA induced biorhythm disruption and downregulated BMAL1 expression through decreasing stability of BMAL1 mRNA via miR-155.

Circadian disruption and sleep disorders in neurodegeneration.

Disruptions of circadian rhythms and sleep cycles are common among neurodegenerative diseases and can occur at multiple levels. Accumulating evidence reveals a bidirectional relationship between disruptions of circadian rhythms and sleep cycles and neurodegenerative diseases. Circadian disruption and sleep disorders aggravate neurodegeneration and neurodegenerative diseases can in turn disrupt circadian rhythms and sleep. Importantly, circadian disruption and various sleep disorders can increase the risk of neurodegenerative diseases. Thus, harnessing the circadian biology findings from preclinical and translational research in neurodegenerative diseases is of importance for reducing risk of neurodegeneration and improving symptoms and quality of life of individuals with neurodegenerative disorders via approaches that normalize circadian in the context of precision medicine. In this review, we discuss the implications of circadian disruption and sleep disorders in neurodegenerative diseases by summarizing evidence from both human and animal studies, focusing on the bidirectional links of sleep and circadian rhythms with prevalent forms of neurodegeneration. These findings provide valuable insights into the pathogenesis of neurodegenerative diseases and suggest a promising role of circadian-based interventions.

Estrogen-Induced LncRNA, LINC02568, Promotes Estrogen Receptor-Positive Breast Cancer Development and Drug Resistance Through Both In Trans and In Cis Mechanisms.

Endocrine therapy is the frontline treatment for estrogen receptor (ER) positive breast cancer patients. However, the primary and acquired resistance to endocrine therapy drugs remain as a major challenge in the clinic. Here, this work identifies an estrogen-induced lncRNA, LINC02568, which is highly expressed in ER-positive breast cancer and functional important in cell growth in vitro and tumorigenesis in vivo as well as endocrine therapy drug resistance. Mechanically, this work demonstrates that LINC02568 regulates estrogen/ERα-induced gene transcriptional activation in trans by stabilizing ESR1 mRNA through sponging miR-1233-5p in the cytoplasm. Meanwhile, LINC02568 contributes to tumor-specific pH homeostasis by regulating carbonic anhydrase CA12 in cis in the nucleus. The dual functions of LINC02568 together contribute to breast cancer cell growth and tumorigenesis as well as endocrine therapy drug resistance. Antisense oligonucleotides (ASO) targeting LINC02568 significantly inhibits ER-positive breast cancer cell growth in vitro and tumorigenesis in vivo. Furthermore, combination treatment with ASO targeting LINC02568 and endocrine therapy drugs or CA12 inhibitor U-104 exhibits synergistic effects on tumor growth. Taken together, the findings reveal the dual mechanisms of LINC02568 in regulating ERα signaling and pH homeostasis in ER-positive breast cancer, and indicated that targeting LINC02568 might represent a potential therapeutic avenue in the clinic.