Autophagy deficiency modulates microglial lipid homeostasis and aggravates tau pathology and spreading.

The autophagy-lysosomal pathway plays a critical role in intracellular clearance and metabolic homeostasis. While neuronal autophagy is known to participate in the degradation of neurofibrillary tangles composed of hyperphosphorylated and misfolded tau protein in Alzheimer's disease and other tauopathies, how microglial-specific autophagy regulates microglial intrinsic properties and neuronal tau pathology is not well understood. We report here that Atg7, a key mediator of autophagosome biogenesis, plays an essential role in the regulation of microglial lipid metabolism and neuroinflammation. Microglia-specific deletion of Atg7 leads to the transition of microglia to a proinflammatory status in vivo and to inflammasome activation in vitro. Activation of ApoE and lipid efflux attenuates the lipid droplets accumulation and inhibits cytokine production in microglial cells with Atg7 deficiency. Functionally, we show that the absence of microglial Atg7 enhances intraneuronal tau pathology and its spreading. Our results reveal an essential role for microglial autophagy in regulating lipid homeostasis, neuroinflammation, and tau pathology.

TFEB regulates lysosomal exocytosis of tau and its loss of function exacerbates tau pathology and spreading.

Neurofibrillary tangles (NFTs) composed of hyperphosphorylated and misfolded tau protein are a pathological hallmark of Alzheimer's disease and other tauopathy conditions. Tau is predominantly an intraneuronal protein but is also secreted in physiological and pathological conditions. The extracellular tau has been implicated in the seeding and propagation of tau pathology and is the prime target of the current tau immunotherapy. However, truncated tau species lacking the microtubule-binding repeat (MTBR) domains essential for seeding have been shown to undergo active secretion and the mechanisms and functional consequences of the various extracellular tau are poorly understood. We report here that the transcription factor EB (TFEB), a master regulator of lysosomal biogenesis, plays an essential role in the lysosomal exocytosis of selected tau species. TFEB loss of function significantly reduced the levels of interstitial fluid (ISF) tau in PS19 mice expressing P301S mutant tau and in conditioned media of mutant tau expressing primary neurons, while the secretion of endogenous wild-type tau was not affected. Mechanistically we found that TFEB regulates the secretion of truncated mutant tau lacking MTBR and this process is dependent on the lysosomal calcium channel TRPML1. Consistent with the seeding-incompetent nature of the truncated tau and supporting the concept that TFEB-mediated lysosomal exocytosis promotes cellular clearance, we show that reduced ISF tau in the absence of TFEB is associated with enhanced intraneuronal pathology and accelerated spreading. Our results support the idea that TFEB-mediated tau exocytosis serves as a clearance mechanism to reduce intracellular tau under pathological conditions and that effective tau immunotherapy should devoid targeting these extracellular tau species.

Overexpression of SNHG12 regulates the viability and invasion of renal cell carcinoma cells through modulation of HIF1α.

BACKGROUND: Cumulative evidences demonstrated the aberrant overexpression of Small Nucleolar RNA Host Gene 12 (SNHG12) in diverse human cancer. However, the expression status and involvement of SNHG12 in renal cell carcinoma is still elusive. METHODS: The expression of SNHG12 was determined by q-PCR. The transcriptional regulation was interrogated by luciferase reporter assay. Cell viability was measured with CCK-8 kit. The anchorage-independent was evaluated by soft agar assay. Cell apoptosis was analyzed by Annexin V/7-AAD double staining. The migration and invasion were determined by trans-well assay and wound scratch closure. The in vivo tumor growth was monitored in xenograft mice model. Protein expression was quantified by immunoblotting. RESULTS: SNHG12 was aberrantly up-regulated in renal carcinoma both in vivo and in vitro. High expression of SNHG12 associated with poor prognosis. Deficiency of SNHG12 significantly suppressed cell viability, anchorage-independent growth and induced apoptosis. In addition, SNHG12 silencing inhibited migrative and invasive in vitro and xenograft tumor growth in vivo. Mechanistically, SNHG12 modulated HIF1α expression via competing with miR-199a-5p, which consequently contributed to its oncogenic potential. MiR-199a-5p inhibition severely compromised SNHG12 silencing-elicited tumor repressive effects. CONCLUSION: Our data uncovered a crucial role of SNHG12-miR-199a-5p-HIF1α axis in human renal cancer.

The crystal structure of red fluorescent protein TagRFP-T reveals the mechanism of its superior photostability.

The red fluorescent protein variant TagRFP-T has greatly improved photostability over its parent molecule, TagRFP, but the underlying mechanism leading to this improvement is to date unknown. The 1.95 Å resolution crystallographic structure of TagRFP-T showed that its chromophore exists as a mixture of cis and trans coplanar isomers in roughly equal proportions. Interestingly, both isomers are able to fluoresce, a property that has never been observed in any other fluorescent protein. We propose a "circular restoration model" for TagRFP-T to explain its superior photostability: There are four co-existing chromophore states (cis/trans protonated/ionized state) that can be driven by light to transform from one state into another. This model also explains how TagRPF-T essentially eliminates the temporary dark state (reversible photobleaching).

MiR-378 suppresses prostate cancer cell growth through downregulation of MAPK1 in vitro and in vivo.

Prostate cancer is one of the biggest health problems for the aging male. To the present, the roles of dysregulated microRNAs in prostate cancer are still unclear. Here, we evaluated the anti-proliferative role of miR-378 in prostate cancer. And, we found that the expression of miR-378 was significantly downregulated in clinical prostate cancer tissues. In vitro assay suggested that overexpression of miR-378-suppressed prostate cancer cell migration and invasion promoted cell apoptosis. Furthermore, we identified and validated MAPK1 as a direct target of miR-378. Ectopic expression of MAPK1 rescues miR-378-suppressed cell migration and invasion. In vivo assay demonstrated that the stably miR-378-overexpressed prostate cancer cells displayed a significantly reduction in tumor growth. Taken together, our data suggested that miR-378 may act as a potential therapeutic target against human prostate cancer.

Intrathecal administration of TRPA1 antagonists attenuate cyclophosphamide-induced cystitis in rats with hyper-reflexia micturition.

BACKGROUND: The activation of TRPA1 channel is implicated in hyper-reflexic micturition similar to overactive bladder. In this study, we aimed to investigate the effects of blocking TRPA1 via intrathecal administration of antagonists on the afferent pathways of micturition in rats with cystitis. METHODS: The cystitis was induced by intraperitoneal cyclophosphamide administration. Cystometry was performed in control and cystitis rats, following the intrathecal injection of the TRPA1 antagonists HC-030031 and A-967079. Real-time PCR, agarose gel electrophoresis, western blotting and immunohistochemistry were used to investigate the levels of TRPA1 mRNA or protein in the bladder mucosa and L6-S1 dorsal root ganglia (DRG). RESULTS: Edema, submucosal hemorrhaging, stiffness and adhesion were noted during removal of the inflamed bladder. The expression of TRPA1 mRNA and protein was higher in the cystitis group in both the mucosa and DRG, but the difference was significant in the DRG (P < 0.05). Intrathecal administration of HC-030031 and A-967079 decreased the micturition reflex in the cystitis group. A 50 µg dose of HC-030031 increased the intercontraction interval (ICI) to 183 % of the no-treatment value (P < 0.05) and decreased the non-voiding contraction (N-VC) to 60 % of control (P < 0.01). Similarly, the treatment with 3 µg A-967079 increased the ICI to 142 % of the control value (P < 0.05) and decreased the N-VC to 77 % of control (P < 0.05). The effects of both antagonists weakened approximately 2 h after injection. CONCLUSIONS: The TRPA1 had a pronounced upregulation in DRG but more slight in mucosa in rat cystitis. The blockade of neuronal activation of TRPA1 by intrathecal administration of antagonists could decrease afferent nerve activities and attenuated detrusor overactivity induced by inflammation.

Structural insights on the catalytic site protection of human carbonyl reductase 1 by glutathione.

The NADPH-dependent human carbonyl reductase 1 (hCBR1), a member of the short-chain dehydrogenase/reductase protein family, plays an important role in the ubiquitous metabolism of endogenous and xenobiotic carbonyl containing compounds. Glutathione (GSH) is also a cofactor of hCBR1, however, its role in the carbonyl reductase function of the enzyme is still unclear. In this study, we presented the crystal structure of hCBR1 in complex with GSH, in the absence of its substrates or inhibitors. Interestingly, we found that the GSH molecule presents in a configuration quite different from that was previously reported when substrate is binding to hCBR1. Our structure indicates that GSH contributes to the substrate selectivity of hCBR1 and protects the catalytic center of hCBR1 through a switch-like mechanism. The isothermal titration calorimetry and enzymology data shows that GSH directly binding with hCBR1 when there's no substrate exist. The enzymology data also shows GSH protects NADPH being attacked by oxidative small molecules. This is the first time that GSH is found to demonstrate such functions as a co-enzyme. Our crystal structure succeeds in providing critical insights into the substrate selectivity of hCBR1 and the interaction between hCBR1 and GSH.

Toll-like receptor 4 and CD11b expressed on microglia coordinate eradication of Candida albicans cerebral mycosis.

The fungal pathogen Candida albicans is linked to chronic brain diseases such as Alzheimer's disease (AD), but the molecular basis of brain anti-Candida immunity remains unknown. We show that C. albicans enters the mouse brain from the blood and induces two neuroimmune sensing mechanisms involving secreted aspartic proteinases (Saps) and candidalysin. Saps disrupt tight junction proteins of the blood-brain barrier (BBB) to permit fungal brain invasion. Saps also hydrolyze amyloid precursor protein (APP) into amyloid ß (Aß)-like peptides that bind to Toll-like receptor 4 (TLR4) and promote fungal killing in vitro while candidalysin engages the integrin CD11b (Mac-1) on microglia. Recognition of Aß-like peptides and candidalysin promotes fungal clearance from the brain, and disruption of candidalysin recognition through CD11b markedly prolongs C. albicans cerebral mycosis. Thus, C. albicans is cleared from the brain through innate immune mechanisms involving Saps, Aß, candidalysin, and CD11b.

Bladder outlet obstruction induced expression of prostaglandin E2 receptor subtype EP4 in the rat bladder: a possible counteractive mechanism against detrusor overactivity.

PURPOSE: Prostaglandins have been implicated as endogenous modulators of bladder function under physiological and pathological conditions. We examined how the expression of each EP receptor subtype changed in association with bladder outlet obstruction and focused on the functional role of EP4 receptor subtype in the bladder with outlet obstruction. MATERIALS AND METHODS: We assessed the gene expression of EP receptor subtypes by reverse transcriptase-polymerase chain reaction. EP4 protein localization was determined by immunohistochemistry. The effect of the selective EP4 agonist ONO-AE1-329 on 50 mM KCl induced contraction of rat bladder strips was examined in vitro. Continuous infusion cystometrograms were done to examine the effect of intravesical perfusion of ONO-AE1-329 on the micturition reflex in urethane anesthetized rats. RESULTS: EP4 receptor genes were largely expressed in bladders with outlet obstruction but absent in controls. EP4 receptor proteins were clearly detected in obstructed bladder detrusor smooth muscle and epithelium. ONO-AE1-329 (100 µM) significantly relaxed KCl induced contraction of bladder strips from rats with bladder outlet obstruction. A significant correlation was found between the relaxant effect of ONO-AE1-329 and whole bladder weight. In rats with bladder outlet obstruction intravesical infusion of 10 µM ONO-AE1-329 significantly increased bladder capacity without changing micturition pressure while it had no effect in controls. CONCLUSIONS: Activation of the EP4 receptors expressed in bladders with outlet obstruction may suppress detrusor muscle contraction and afferent activity. This might be a compensatory mechanism to counteract the deterioration of storage function in bladders with outlet obstruction.

Suppression of NF-kappaB by cyclosporin a and tacrolimus (FK506) via induction of the C/EBP family: implication for unfolded protein response.

Immunosuppressive agents cyclosporin A (CsA) and tacrolimus (FK506) inhibit cytokine production by activated lymphocytes through interfering with calcineurin. However, little is known about their effects on the function of nonlymphoid cells. We found that, in renal tubular cells, induction of MCP-1 by inflammatory cytokines was blunted by CsA and FK506. This suppression was correlated with induction of unfolded protein response (UPR) evidenced by endogenous and exogenous indicators. The induction of UPR by these agents was reversible and observed generally in other nonimmune cells. Furthermore, administration with CsA in reporter mice caused rapid, systemic induction of UPR in vivo. In TNF-alpha-treated cells, suppression of MCP-1 by CsA or FK506 was associated with blunted responses of NF-kappaB, the crucial regulator of MCP-1. The suppression of NF-kappaB was reproduced by other inducers of UPR including AB(5) subtilase cytotoxin, tunicamycin, thapsigargin, and A23187. CsA and FK506, as well as other UPR inducers, caused up-regulation of C/EBP family members, especially C/EBPbeta and CHOP (C/EBP homologous protein), and overexpression of either C/EBPbeta or CHOP significantly attenuated TNF-alpha-triggered NF-kappaB activation. Furthermore, down-regulation of C/EBPbeta by small interfering RNA substantially reversed the suppressive effect of CsA on TNF-alpha-induced MCP-1 expression. These results suggested that CsA and FK506 confer insensitiveness to TNF-alpha on resident cells through UPR-dependent induction of the C/EBP family members.

Role of FoxO transcription factors in aging and age-related metabolic and neurodegenerative diseases.

Aging happens to all of us as we live. Thanks to the improved living standard and discovery of life-saving medicines, our life expectancy has increased substantially across the world in the past century. However, the rise in lifespan leads to unprecedented increases in both the number and the percentage of individuals 65 years and older, accompanied by the increased incidences of age-related diseases such as type 2 diabetes mellitus and Alzheimer's disease. FoxO transcription factors are evolutionarily conserved molecules that play critical roles in diverse biological processes, in particular aging and metabolism. Their dysfunction is often found in the pathogenesis of many age-related diseases. Here, we summarize the signaling pathways and cellular functions of FoxO proteins. We also review the complex role of FoxO in aging and age-related diseases, with focus on type 2 diabetes and Alzheimer's disease and discuss the possibility of FoxO as a molecular link between aging and disease risks.

Primary bladder schwannoma: a case report and literature review.

Primary bladder schwannoma is an extremely rare bladder tumor that originates from Schwann cells in the nerve sheath and often associated with von Reichnhausen's disease. Isolated cases of urinary bladder schwannoma are incredibly rare with no more than 1/1,000 of bladder tumours. We report a 33-year-old female patient who did not have any symptoms and was found by computed tomography (CT). Preoperative cystoscopy revealed a large sessile and smooth-surfaced mass on the anterior top of the bladder. Then she was successfully managed by partial cystectomy. Hematoxylin-eosin (HE) staining and immunohistochemistry (IHC) confirmed the mass was schwannoma. She was discharged 16 days after admission. In addition, she was followed up without intravesical recurrence or metastases for 29 months. Subsequently, literatures in PubMed (https://pubmed.ncbi.nlm.nih.gov/) accessed to bladder schwannoma since 1993 are searched and reviewed, more clinical data are provided to better assist in the diagnosis and treatment. In summary, bladder schwannoma is a rare benign tumor of the urinary system. Imaging examination and cystoscopy have a hint on the disease to a certain extent. The first choice of treatment is surgical resection, pathology is the gold standard and S-100 is usually positive. On account of the possibility of malignant transformation of the disease, Long-term follow-up is necessary.

FoxO3 deficiency in cortical astrocytes leads to impaired lipid metabolism and aggravated amyloid pathology.

The rise of life expectancy of the human population is accompanied by the drastic increases of age-associated diseases, in particular Alzheimer's disease (AD), and underscores the need to understand how aging influences AD development. The Forkhead box O transcription factor 3 (FoxO3) is known to mediate aging and longevity downstream of insulin/insulin-like growth factor signaling across species. However, its function in the adult brain under physiological and pathological conditions is less understood. Here, we report a region and cell-type-specific regulation of FoxO3 in the central nervous system (CNS). We found that FoxO3 protein levels were reduced in the cortex, but not hippocampus, of aged mice. FoxO3 was responsive to insulin/AKT signaling in astrocytes, but not neurons. Using CNS Foxo3-deficient mice, we reveal that loss of FoxO3 led to cortical astrogliosis and altered lipid metabolism. This is associated with impaired metabolic homoeostasis and ß-amyloid (Aß) uptake in primary astrocyte cultures. These phenotypes can be reversed by expressing a constitutively active FOXO3 but not a FOXO3 mutant lacking the transactivation domain. Loss of FoxO3 in 5xFAD mice led to exacerbated Aß pathology and synapse loss and altered local response of astrocytes and microglia in the vicinity of Aß plaques. Astrocyte-specific overexpression of FOXO3 displayed opposite effects, suggesting that FoxO3 functions cell autonomously to mediate astrocyte activity and also interacts with microglia to address Aß pathology. Our studies support a protective role of astroglial FoxO3 against brain aging and AD.

[The clinical analysis of 62 cases of the urothelial inverted papilloma].

OBJECTIVE: To investigate the clinical manifestation, biological behavior, diagnosis and treatment of the urothelial inverted papilloma. METHODS: Sixty-two cases of urothelial inverted papilloma were analyzed retrospectively from January 1990 to August 2008. Of the 62 patients, 51 were men and 11 were women. The average age at presentation was 56.4 years old. Fifty-six cases were solitary tumors and 6 were multiple. The most common compliant was macroscopic hematuria. The tumor located at the ureter in 5 cases. Of these cases, 4 were treated by local excision, 1 by nephroureterectomy. One case of multiple ureteral inverted papilloma with coexistent bladder inverted papilloma was treated by total cystectomy. The tumor located at the bladder in 52 cases, with 44 treated by transurethral resection of bladder tumor, 6 by partial cystectomy, 2 by total cystectomy. Four cases had the tumor located at the urethra, with 1 treated by transurethral resection of tumor, 3 by tumorectomy. RESULTS: The postoperative pathological diagnosis of all the 62 cases was inverted papilloma, synchronous urothelial carcinoma in 7. Follow-up data were available in 49 cases. Two cases had a recurrence at 7 months and 79 months, respectively. Three case of subsequent transitional cell carcinoma developed 18 months, 2 years and 6 years later, respectively. CONCLUSIONS: Inverted urothelial papilloma is a kind of benign tumor. It should be differentiated from malignant urothelial tumors. Surgical operation is the main treatment choice. Cystoscopic surveillance and followup are necessary after the operation regularly.

Microglia and amyloid precursor protein coordinate control of transient Candida cerebritis with memory deficits.

Bloodborne infections with Candida albicans are an increasingly recognized complication of modern medicine. Here, we present a mouse model of low-grade candidemia to determine the effect of disseminated infection on cerebral function and relevant immune determinants. We show that intravenous injection of 25,000 C. albicans cells causes a highly localized cerebritis marked by the accumulation of activated microglial and astroglial cells around yeast aggregates, forming fungal-induced glial granulomas. Amyloid precursor protein accumulates within the periphery of these granulomas, while cleaved amyloid beta (Aß) peptides accumulate around the yeast cells. CNS-localized C. albicans further activate the transcription factor NF-κB and induce production of interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor (TNF), and Aß peptides enhance both phagocytic and antifungal activity from BV-2 cells. Mice infected with C. albicans display mild memory impairment that resolves with fungal clearance. Our results warrant additional studies to understand the effect of chronic cerebritis on cognitive and immune function.

Roles of mechanosensitive ion channels in bladder sensory transduction and overactive bladder.

In the storage phase, mechanical stretch stimulates bladder afferents. These signals generate sensations and trigger voiding responses, however the precise mechanisms by which mechanical stimuli excite bladder afferents are yet to be explored. For mechanosensory transduction, the presence of mechanosensors is essential in the peripheral sensory systems including sensory nerve endings, urothelium and others. There is increasing evidence that mechanosensitive ion channels, such as degenerin/epithelial Na(+) channel (ENaC) and transient receptor potential (TRP) channel families, play key roles in the mechanosensory transduction of the urinary bladder. Pharmacological interventions targeting mechanosensitive ion channels may provide a new strategy for the treatment of bladder dysfunction.

Rapid, transient induction of ER stress in the liver and kidney after acute exposure to heavy metal: evidence from transgenic sensor mice.

Endoplasmic reticulum (ER) stress-responsive alkaline phosphatase (ES-TRAP) serves as a sensitive indicator for ER stress. In response to heavy metals including cadmium, nickel and cobalt, hepatocytes and renal tubular cells expressing ES-TRAP exhibited ER stress and decreased ES-TRAP activity. In ES-TRAP transgenic mice, acute exposure to cadmium showed rapid, transient decreases in the activity of serum ES-TRAP. It was inversely correlated with the induction of endogenous ER stress markers in the liver and kidney. Our result provides first evidence for the acute, reversible induction of ER stress in vivo after exposure to heavy metal.

Four cases of enterovesical fistula and the importance of CT in the diagnosis.

Enterovesical fistula is an abnormal communication between the urinary bladder and intestine. Diverticulitis is the most common aetiology, accounting for approximately 50-70% of cases, and malignancy is the second most common cause, accounting for approximately 20% of cases. However, most patients are hospitalized because of urinary symptoms. The disease can be misdiagnosed if patients have been symptomatic for a long time before the diagnosis is made. Detection of enterovesical fistula and the underlying disease is important. However, the optimal diagnostic methods have not been clarified. CT scan is the most sensitive diagnostic modality, but should be backed up with cystoscopy, cystography, colonoscopy and barium enema.

Expression of ß-adrenergic receptor subtypes in human normal and dilated ureter.

BACKGROUND: Ureter peristalsis is a basic physiological function regulated by myogenic and neurogenic factors. The distribution and function of ß-adrenergic receptors (ß-AR) in the human ureter remain unknown. The aim of this study was to investigate the expression of ß-AR subtypes in the normal and dilated human ureter. METHODS: The upper, middle, and lower segments of normal and dilated ureters were collected from patients undergoing surgery for carcinoma of the kidney and upper urinary tract and ureteral stenosis. The mucosa and muscular layers were separated. Expression of ß1-AR, ß2-AR, and ß3-AR mRNA and protein levels were detected by real-time PCR, western blot, and immunohistochemistry. RESULTS: In both mucosa and muscular layers, the mRNA and protein expressions of ß1-AR, ß2-AR, and ß3-AR were lower in the dilated ureter compared with the normal ureter. ß1-AR mRNA was significantly decreased (by 76.64%; P < 0.01) in the mucosa layer of the middle segment of the dilated ureter. ß1-AR and ß3-AR mRNA were significantly decreased (by 75.53 and 53.62%, respectively; P < 0.01) in the muscular layer of the lower segment of the dilated ureter. Similar findings were observed for protein expression. CONCLUSIONS: The downregulation of ß-ARs after ureter dilation, particularly for ß1-AR and ß3-AR in the muscular layer, suggests a potential compensatory mechanism involving increased contraction of the ureter to push urine through the obstruction. Thus, ß-ARs may be a potential target for treatment of ureter obstruction.

MiR-345 suppresses proliferation, migration and invasion by targeting Smad1 in human prostate cancer.

INTRODUCTION: The roles of dysregulated microRNAs in prostate cancer metastasis are still unknown. In this study, we found that the expression of miR-345 was significantly downregulated in prostate cancer and clinical prostate cancer tissues. MATERIALS, METHODS AND RESULTS: Overexpression of miR-345 in prostate cancer cells suppressed proliferation, migration and invasion. Using nude mice model, we revealed that miR-345 inhibits the growth of prostate cancer cells in vivo and in vitro. Furthermore, we identified and validated Smad1 as a direct target of miR-345. Ectopic expression of Smad1 without its 3'-UTR rescued miR-345-induced cell migration and invasion inhibition. CONCLUSION: Taken together, our data suggest that miR-345 exerts a suppressive effect on prostate cancer proliferation, invasion and migration through downregulation of Smad1.