Selective orexin 2 receptor blockade alleviates cognitive impairments and the pathological progression of Alzheimer's disease in 3xTg-AD mice

The orexin system is closely related to the pathogenesis of Alzheimer's disease (AD). Orexin-A aggravates cognitive dysfunction and increases amyloid β (Aβ) deposition in AD model mice, but studies of different dual orexin receptor (OXR) antagonists in AD have shown inconsistent results. Our previous study revealed that OX1R blockade aggravates cognitive deficits and pathological progression in 3xTg-AD mice, but the effects of OX2R and its potential mechanism in AD have not been reported. In the present study, OX2R was blocked by oral administration of the selective OX2R antagonist MK-1064, and the effects of OX2R blockade on cognitive dysfunction and neuropsychiatric symptoms in 3xTg-AD mice were evaluated via behavioral tests. Then, immunohistochemistry, western blotting and ELISA were used to detect Aβ deposition, tau phosphorylation and neuroinflammation, and electrophysiological and wheel-running activity recording were recorded to observe hippocampal synaptic plasticity and circadian rhythm. The results showed that OX2R blockade ameliorated cognitive dysfunction, improved LTP depression, increased the expression of PSD-95, alleviated anxiety- and depression-like behaviors and circadian rhythm disturbances in 3xTg-AD mice, and reduced Aβ pathology, tau phosphorylation and neuroinflammation in the brains of 3xTg-AD mice. These results indicated that chronic OX2R blockade exerts neuroprotective effects in 3xTg-AD mice by reducing AD pathology at least partly through improving circadian rhythm disturbance and the sleep-wake cycle and that OX2R might be a potential target for the prevention and treatment of AD; however, the potential mechanism by which OX2R exerts neuroprotective effects on AD needs to be further investigated.

Diurnal Characteristics of the Orexin System Genes and Its Effects on Pathology at Early Stage in 3xTg-AD Mice

Orexin and its receptors are closely related to the pathogenesis of Alzheimer's disease (AD). Although the expression of orexin system genes under physiological condition has circadian rhythm, the diurnal characteristics of orexin system genes, and its potential role in the pathogenesis in AD are unknown. In the present study, we hope to elucidate the diurnal characteristics of orexin system genes at the early stage of AD, and to investigate its potential role in the development of AD neuropathology. We firstly detected the mRNA levels of orexin system genes, AD risk genes and core clock genes (CCGs) in hypothalamus and hippocampus in 6-month-old male 3xTg-AD mice and C57BL/6J (wild type, WT) control mice, then analyzed diurnal expression profiles of all genes using JTK_CYCLE algorithm, and did the correlation analysis between expression of orexin system genes and AD risk genes or CCGs. In addition, the expression of β-amyloid protein (Aβ) and phosphorylated tau (p-tau) protein were measured. The results showed that the diurnal mRNA expression profiles of PPO, OX1R, OX2R, Bace2, Bmal1, Per1, Per2 and Cry1 in the hypothalamus, and gene expression of OX1R, OX2R, Bace1, Bmal1, Per1 and Cry2 in the hippocampus in 3xTg-AD mice were different from that in WT mice. Furthermore, there is positive correlation between orexin system genes and AD risk genes or CCGs in the brain in 3xTg-AD mice. In addition, the expression of Aβ and p-tau in hippocampus in 3xTg-AD mice were significantly increased, and the expression of p-tau is higher in night than in day. These results indicate that the abnormal expression profiles of orexin system genes and its interaction with AD risk genes or CCGs might exert important role in the pathogenesis of AD, which will increase the expression of Aβ and p-tau, and accelerate the development of AD.

Orexin-A aggravates cognitive deficits in 3xTg-AD mice by exacerbating synaptic plasticity impairment and affecting amyloid β metabolism

Dementia is the main clinical feature of Alzheimer's disease (AD). Orexin has recently been linked to AD pathogenesis, and exogenous orexin-A (OXA) aggravates spatial memory impairment in APP/PS1 mice. However, the effects of OXA on other types of cognitive deficits, especially in 3xTg-AD mice exhibiting both plaque and tangle pathologies, have not been reported. Furthermore, the potential electrophysiological mechanism by which OXA affects cognitive deficits and the molecular mechanism by which OXA increases amyloid β (Aβ) levels are unknown. In the present study, the effects of OXA on cognitive functions, synaptic plasticity, Aβ levels, tau hyperphosphorylation, BACE1 and NEP expression, and circadian locomotor rhythm were evaluated. The results showed that OXA aggravated memory impairments and circadian rhythm disturbance, exacerbated hippocampal LTP depression, and increased Aβ and tau pathologies in 3xTg-AD mice by affecting BACE1 and NEP expression. These results indicated that OXA aggravates cognitive deficits and hippocampal synaptic plasticity impairment in 3xTg-AD mice by increasing Aβ production and decreasing Aβ clearance through disruption of the circadian rhythm and sleep-wake cycle.

Selective orexin 1 receptor antagonist SB-334867 aggravated cognitive dysfunction in 3xTg-AD mice

Cognitive dysfunction is the main clinical manifestation of Alzheimer's disease (AD). Previous research found that elevated orexin level in the cerebrospinal fluid was closely related to the course of AD, and orexin-A treatment could increase amyloid β protein (Aβ) deposition and aggravate spatial memory impairment in APP/PS1 mice. Furthermore, recent research found that dual orexin receptor (OXR) antagonist might affect Aβ level and cognitive dysfunction in AD, but the effects of OX1R or OX2R alone is unreported until now. Considering that OX1R is highly expressed in the hippocampus and plays important roles in learning and memory, the effects of OX1R in AD cognitive dysfunction and its possible mechanism should be investigated. In the present study, selective OX1R antagonist SB-334867 was used to block OX1R. Then, different behavioral tests were performed to observe the effects of OX1R blockade on cognitive function of 3xTg-AD mice exhibited both Aβ and tau pathology, in vivo electrophysiological recording and western blot were used to investigate the potential mechanism. The results showed that chronic OX1R blockade aggravated the impairments of short-term working memory, long-term spatial memory and synaptic plasticity in 9-month-old female 3xTg-AD mice, increased levels of soluble Aβ oligomers and p-tau, and decreased PSD-95 expression in the hippocampus of 3xTg-AD mice. These results indicate that the detrimental effects of SB-334867 on cognitive behaviors in 3xTg-AD mice are closely related to the decrease of PSD-95 and depression of in vivo long-term potentiation (LTP) caused by increased Aβ oligomers and p-tau.

[Preliminary results of biportal endoscopic lumbar interbody fusion, decompression and pedicle screw insertion assisted with endoscopic technique for lumbar spinal stenosis combined with spondylolisthesis or instability]

Objectives: To evaluate the preliminary clinical outcomes of biportal endoscopic lumbar interbody fusion (BE-LIF), decompression and pedicle screw insertion assisted with endoscopic technique for lumbar spinal stenosis combined with spondylolisthesis or instability. Methods: The data of 9 patients with single-level lumbar spinal stenosis who underwent BE-LIF, decompression and pedicle screw insertion assisted with biportal endoscopy in Xinjiang Production and Construction Corps Hospital from March 1st 2022 to April 30th 2022 were analyzed retrospectively. The visual analogue scales (VAS) for pain in back and legs, and the Oswestry disability index (ODI) of all the patients were collected before operation, on the third day after operation and at the last follow-up. Moreover, the operation time, intra-operation blood loss, radiation shots for pedicle screw insertion, post-operation drainage and ambulation time were recorded. The screw position was checked with CT after the operation. Results: All the patients were female with a mean age of (70.3±8.4) years (ranged 56-84 years); the patients were followed-up for 12-16 weeks. All 9 patients had good clinical results. The VAS scores for back pain on the third day after operation and at the last follow-up were both significantly lower than that preoperatively[(2.9±0.6), (1.8±0.4) vs (6.4±1.1) points, both P<0.05]. The VAS scores for leg pain on the third day after operation and at the last follow-up were both significantly lower than that preoperatively[(1.9±0.3), (1.4±0.5) vs (7.3±1.6) points, P<0.05]. The ODI scores at last follow-up was significantly lower than that before the operation ((24.0%±6.5% vs 55.7%±12.8%, P<0.05). The intra-operative blood loss was (177±103) ml, the drainage amounts post-operation was (122±56) ml, the operation time was (207.8±32.7)min, the ambulation time was (2.3±0.5) days. The total radiation shots for pedicle screw insertion were 20-42 times, the average radiation shots per screw was (6.9±1.5) times. No severe complications or adverse events occurred. No nerve root injury or dural tear occurred in the operation, and no revision surgery needed. Conclusions: The pedicle screw insertion assisted with biportal endoscopic technique can decrease the radiation exposure with good feasibility and safety during the BE-LIF. The BE-LIF combined with the pedicle screw insertion assisted with biportal endoscopy is an effective and safe surgery for lumbar spinal stenosis with good early results.

[Progression and clinical application in unilateral biportal endoscopic]

With the advantages of less operative injury and quicker postoperative recovery time, percutaneous endoscopic spine surgery system is currently one of the most widely used minimal invasive spine surgery techniques in China. However, this technique usually requires surgeon to operate in a single cannula, which brings much inconvenience such as limited vision, small range of motion and low efficiency. Meanwhile, the increasingly popular technique of unilateral biportal endoscopic (UBE) surgery possesses the advantages of better operation visual field, more flexible in operation, shorter learning curve period, handier surgical instruments for spine surgeon, and minimize radiation dosage caused by intraoperative fluoroscopy when comparing with single cannula endoscopic technique, since UBE requires an additional portal for surgical instruments while the anther portal is placed for arthroscope and pressure pump irrigation system. This technique has been applied to the treatment of degenerative diseases of cervical and lumbar spine, facet cyst, spinal epidural lipomatosis and abscess, and has achieved satisfactory clinical results.

Measurement of Heavy Ion Irradiation Induced In-Plane Strain in Patterned Face-Centered-Cubic Metal Films: An in Situ Study

Nanocrystalline Ag, Cu, and Ni thin films and their coarse grained counterparts are patterned using focused ion beam and then irradiated by Kr ions within an electron microscope at room temperature. Irradiation induced in-plane strain of the films is measured by tracking the location of nanosized holes. The magnitude of the strain in all specimens is linearly dose-dependent and the strain rates of nanocrystalline metals are significantly greater as compared to that of the coarse grained metals. Real-time microscopic observation suggests that substantial grain boundary migration and grain rotation are responsible for the significant in-plane strain.

What determines the interfacial configuration of Nb/Al2O3 and Nb/MgO interface

Nb films are deposited on single crystal Al₂O₃ (110) and MgO(111) substrates by e-beam evaporation technique. Structure of Nb films and orientation relationships (ORs) of Nb/Al₂O₃ and Nb/MgO interface are studied and compared by the combination of experiments and simulations. The experiments show that the Nb films obtain strong (110) texture, and the Nb film on Al₂O₃(110) substrate shows a higher crystalline quality than that on MgO(111) substrate. First principle calculations show that both the lattice mismatch and the strength of interface bonding play major roles in determining the crystalline perfection of Nb films and ORs between Nb films and single crystal ceramic substrates. The fundamental mechanisms for forming the interfacial configuration in terms of the lattice mismatch and the strength of interface bonding are discussed.

Extraordinary light absorptance in graphene superlattices

Extraordinary absorption decrease in graphene superlattices in the visible range is presented. Due to competition between loss and resonant reflection at resonance, the absorption displays non-monotonic behavior. As the period number increases above a certain critical value, absorption decreases with the increase in the period number. This is in contrast to ordinary absorption for a non-resonant condition, which monotonically increases with the period number. Moreover, this extraordinary property can also be controlled by applying a gate voltage to graphene sheets. The results provide not only a new understanding of graphene physics but also an application in nanophotonics and optoelectronics.

In situ study of defect migration kinetics and self-healing of twin boundaries in heavy ion irradiated nanotwinned metals

High energy particles introduce severe radiation damage in metallic materials, such as Ag. Here we report on the study on twin boundary (TB) affected zone in irradiated nanotwinned Ag wherein time accumulative defect density and defect diffusivity are substantially different from those in twin interior. In situ studies also reveal surprising resilience and self-healing of TBs in response to radiation. This study provides further support for the design of radiation-tolerant nanotwinned metallic materials.

Blocking of c-FLIP(L)--independent cycloheximide-induced apoptosis or Fas-mediated apoptosis by the CC chemokine receptor 9/TECK interaction

Chemokines play a pivotal role in regulating leukocyte migration as well as other biological functions. CC chemokine receptor 9 (CCR9) is a specific receptor for thymus-expressed CC chemokine (TECK). It is shown here that engagement of CCR9 with TECK leads to phosphorylation of Akt (protein kinase B), mitogen-activated protein kinases (MAPKs), glycogen synthase kinase--3 beta (GSK-3 beta), and a forkhead transcription factor, FKHR, in a human T-cell line, MOLT4, that naturally expresses CCR9. By means of chemical inhibitors, it is shown that phosphoinositide-3 kinase (PI-3 kinase), but not MAPK, is required for CCR9-mediated chemotaxis. Akt, GSK-3 beta, FKHR, and MAPK have been previously implicated in cell survival signals in response to an array of death stimuli. When MOLT4 cells, which expressed Fas as well as CXCR4, were stimulated with cycloheximide (CHX), an agonistic anti-Fas antibody, or a combination of these, the cells rapidly underwent apoptosis. However, costimulation of MOLT4 cells with TECK or stromal derived factor--1 significantly blocked CHX-mediated apoptosis, whereas stimulation only with TECK partially blocked Fas-mediated apoptosis. Concomitant with this blocking, cleavage of poly (adenosine 5'-diphosphate--ribose) polymerase and activation of caspase 3 were significantly attenuated, but the expression level of FLICE inhibitory protein c-FLIP(L), which had been shown to be regulated by CHX, was unchanged. This demonstrates that activation of CCR9 leads to phosphorylation of GSK-3 beta and FKHR and provides a cell survival signal to the receptor expressing cells against CHX. It also suggests the existence of a novel pathway leading to CHX-induced apoptosis independently of c-FLIP(L). (Blood. 2001;98:925-933)

SIMPL is a tumor necrosis factor-specific regulator of nuclear factor-kappaB activity

The IL-1 receptor-associated kinase (IRAK/mPLK) is linked to the regulation of nuclear factor-kappaB (NF-kappaB)-dependent gene expression. Here we describe a novel binding partner of IRAK/mPLK that we term SIMPL (signaling molecule that associates with the mouse pelle-like kinase). Overexpression of SIMPL leads to the activation of NF-kappaB-dependent promoters, and inactivation of SIMPL inhibits IRAK/mPLK as well as tumor necrosis factor receptor type I-induced NF-kappaB activity. Dominant inhibitory alleles of IkappaB kinase (IKKalpha or IKKbeta) block the activation of NF-kappaB by IRAK/mPLK and SIMPL. Furthermore, SIMPL binds IRAK/mPLK and the IKKs in vitro and in vivo. In the presence of antisense mRNA to SIMPL, the physical association between IRAK/mPLK and IKKbeta but not IRAK/mPLK and IKKalpha is greatly diminished. Moreover, dominant-negative SIMPL blocks IKKalpha- or IKKbeta-induced NF-kappaB activity. These results lead us to propose a model in which SIMPL functions to regulate NF-kappaB activity by linking IRAK/mPLK to IKKbeta/alpha-containing complexes.

The seventh transmembrane domain of cc chemokine receptor 5 is critical for MIP-1beta binding and receptor activation: role of MET 287

CC chemokine receptor 5 (CCR5) is a high-affinity receptor for macrophage inflammatory protein (MIP)-1beta and functions as the major coreceptor for entry of macrophage-tropic (M-tropic) human immunodeficiency virus type 1 (HIV-1). To evaluate the role of transmembrane domains (TM) in the receptor function of CCR5, the seventh transmembrane domain (TM7) was examined in a series of chimeric receptor constructs including CCR5TM (CCR5 backbone/CCR5 TM7 replaced with CCR1 TM7) and mutants of CCR5TM. The CCR5TM chimera exhibited a dramatic reduction in receptor activation, as well as little or no MIP-1beta binding. Further mutational analysis revealed that Met 287 in TM7 of CCR5 is a critical molecular determinant for both MIP-1beta binding and receptor activation. Interestingly, all of the chimeric/mutated receptors were biologically active in an HIV-1 coreceptor fusion assay, demonstrating that chemokine binding is independent of HIV-1 coreceptor activity.

Thymus size and its relationship to perinatal events

A retrospective study was conducted to assess radiographically the thymus size in well and sick neonates and to search for a possible relationship to perinatal events. Thymus size was expressed as cardiothymic:thoracic ratio (CT/T) by measuring the width of the cardiothymic shadow at the level of carina and dividing it by the width of the thorax at the costophrenic angles. The CT/T was measured on chest radiographs obtained on day 1 in well term neonates consecutively born in our nursery and sick neonates with meconium staining of the amniotic fluid, meconium aspiration syndrome or respiratory distress syndrome (RDS). Neonates with congenital anomalies, congenital heart disease or intrauterine growth retardation were excluded. There were no significant relationships between CT/T and sex, birth route, birthweight or gestational age in well and sick term neonates. The CT/T were comparable among well and sick term neonates and were significantly greater in the preterm neonates with RDS than in the preterm neonates without RDS. The CT/T was correlated to the birth route only in the preterm neonates. We conclude that thymus involution in the perinatal period is a complex process and the response is different between term and preterm neonates.

A newly identified member of tumor necrosis factor receptor superfamily (TR6) suppresses LIGHT-mediated apoptosis

TR6 (decoy receptor 3 (DcR3)) is a new member of the tumor necrosis factor receptor (TNFR) family. TR6 mRNA is expressed in lung tissues and colon adenocarcinoma, SW480. In addition, the expression of TR6 mRNA was shown in the endothelial cell line and induced by phorbol 12-myristate 13-acetate/ionomycin in Jurkat T leukemia cells. The open reading frame of TR6 encodes 300 amino acids with a 29-residue signal sequence but no transmembrane region. Using histidine-tagged recombinant TR6, we screened soluble forms of TNF-ligand proteins with immunoprecipitation. Here, we demonstrate that TR6 specifically binds two cellular ligands, LIGHT (herpes virus entry mediator (HVEM)-L) and Fas ligand (FasL/CD95L). These bindings were confirmed with HEK 293 EBNA cells transfected with LIGHT cDNA by flow cytometry. TR6 inhibited LIGHT-induced cytotoxicity in HT29 cells. It has been shown that LIGHT triggers apoptosis of various tumor cells including HT29 cells that express both lymphotoxin beta receptor (LTbetaR) and HVEM/TR2 receptors. Our data suggest that TR6 inhibits the interactions of LIGHT with HVEM/TR2 and LTbetaR, thereby suppressing LIGHT- mediated HT29 cell death. Thus, TR6 may play a regulatory role for suppressing in FasL- and LIGHT-mediated cell death.

Identification of a novel activation-inducible protein of the tumor necrosis factor receptor superfamily and its ligand

Among members of the tumor necrosis factor receptor (TNFR) superfamily, 4-1BB, CD27, and glucocorticoid-induced tumor necrosis factor receptor family-related gene (GITR) share a striking homology in the cytoplasmic domain. Here we report the identification of a new member, activation-inducible TNFR family member (AITR), which belongs to this subfamily, and its ligand. The receptor is expressed in lymph node and peripheral blood leukocytes, and its expression is up-regulated in human peripheral mononuclear cells mainly after stimulation with anti-CD3/CD28 monoclonal antibodies or phorbol 12-myristate 13-acetate/ionomycin. AITR associates with TRAF1 (TNF receptor-associated factor 1), TRAF2, and TRAF3, and induces nuclear factor (NF)-kappaB activation via TRAF2. The ligand for AITR (AITRL) was found to be an undescribed member of the TNF family, which is expressed in endothelial cells. Thus, AITR and AITRL seem to be important for interactions between activated T lymphocytes and endothelial cells.

Regulatory region with putA gene of proline dehydrogenase that links to the lum and the lux operons in Photobacterium leiognathi

Nucleotide sequence of regulatory region (R & R) with putA gene (EMBL Accession No. U39227) from Photobacterium leiognathi PL741 has been determined, and the putA gene encoded amino acid sequence of proline dehydrogenase is deduced. Alignment and comparison of proline dehydrogenase of P. leiognathi with the proline dehydrogenase domain in the PutA protein of Escherichia coli and Salmonella typhimurium show that they are homologous. Nucleotide sequence reveals that regulatory region with the putA gene is linked to the lum and lux operons in genome; the gene order is <--putA--R & R(I)<--ter-lumQ-lumP-R & R-luxC-luxD-luxA-luxB-luxE--> (R & R: regulatory region; ter:transcriptional terminator), whereas the R & R is the regulatory region for the lum and the lux operons, ter is the transcriptional terminator for the lum operon, and R & R(I) apparently is the regulatory region for the putA and related genes. Nucleotide sequence analysis illustrates the specific inverted repeat (SIR), cAMP-CRP consensus sequence, canonical -10/-35 promoter, putative operator and Shine-Dalgarno (SD) sequence on the regulatory region R & R(I) for the putA and related genes; it suggests that the putA and related genes are simply linked to the lum and the lux operons in genome, the regulatory region R & R(I) is independent for the putA and related genes.

The lumQ gene is linked to the lumP gene and the lux operon in Photobacterium leiognathi

The nucleotide sequence of the designated lumQ gene (EMBL accession No. U35231) from Photobacterium leiognathi PL741 has been determined, and the encoded amino acid sequence is deduced. The LumQ protein has a calculated M(r) of 28,416 and comprises 248 amino acid residues. The lumQ gene is identified as the envY-like gene by significant similarity of the encoded protein with the EnvY and AdiY proteins of E. coli; there the envY gene encodes the porin thermoregulatory protein EnvY, and the adiY gene encodes the putative transcriptional regulator protein AdiY. It suggests that the lumQ gene of P. leiognathi is orthologous to the envY and adiY genes of E. coli. The function of the protein encoded by the lumQ gene from P. leiognathi is not really defined yet, it is likely to be the DNA-binding protein related to the araC and xylS family of transcriptional regulators. The lumQ and lumP genes form the lum operon which linked to the lux operon, but run in the opposite direction. The gene order of the lum and the lux operon is < -ter-lumQ-lumP-R&R-luxC-luxD-luxA-luxB- luxN-luxE- > (R&R: regulatory region; ter: transcriptional terminator); whereas the regulatory region (R&R) includes two promoter systems, PR-promoter for the lux operon and PL-promoter for the lum operon; ter is the transcriptional terminator of the lum operon.

[Clinical study on treatment of peptic ulcer with bushen kangkui decoction]

The clinical controlled study of Bushen Kangkui Decoction (BSKKD) on 150 peptic ulcer patients showed that it had a similar effect to injectio cimetidine, and had a lower rate of relapse. And the long-term therapeutic effect was better than that of injectio cimetidine. Simultaneous RIA showed that PGE2 of most treated patients was below normal level before the treatment, but it has increased in various degree after the treatment. The patients under the treatment of BSKKD had significant difference in PGE2 level (P < 0.05), while those treated with injectio cimetidine didn't have (P > 0.05). So the BSKKD has an effect on the increase of PGE2 level of the peptic ulcer patients.