Verification of the association between cognitive decline and olfactory dysfunction using a DEmentia screening kit in subjects with Alzheimer's dementia, mild cognitive impairment, and normal cognitive function (DESK study): A multicenter, open-label, interventional study.

Background and purpose: Olfactory dysfunction may be an early symptom of degenerative neurological disorders such as mild cognitive impairment (MCI), which may progress to cognitive decline and Alzheimer's disease (AD). We investigated the relationship between cognitive decline and olfactory dysfunction in healthy controls and patients with MCI or AD using the DEmentia Screening Kit (DESK), an olfactory identification assessment tool designed for Japanese populations. Methods: In this multicenter, open-label, interventional study conducted from 16 September 2020 to 30 April 2021, participants underwent olfactory tests using the DESK tool. This included 10 odorants at two concentrations (weak/strong) including toothpaste, butter, and India ink. Results: Among 223 participants, 100, 61, and 62 were healthy controls, MCI patients, and AD patients (mean ages, 57.4, 72.8, and 76.3 years; total DESK olfaction scores, 18.4, 14.7, and 7.4), respectively. Significant differences in total olfaction scores were observed between groups (healthy controls vs MCI, healthy controls vs AD, and MCI vs AD). Significant between-group total score differences were shown for olfaction scores with both the 10 strong and 10 weak odorant varieties. Conclusion: The DESK tool may discriminate between healthy individuals and those with MCI or AD, facilitating early screening for cognitive decline among Japanese patients, although the effect of age on DESK olfaction scores has not been fully explored.

Influence of atmospheric pressure low-temperature plasma treatment on the shear bond strength between zirconia and resin cement.

PURPOSE: Zirconia exhibits excellent strength and high biocompatibility in technological applications and it is has therefore been investigated for clinical applications and research. Before setting prostheses, a crown prosthesis inner surface is sandblasted with alumina to remove contaminants and form small cavities. This alumina sandblasting causes stress-induced phase transition of zirconia. Atmospheric-pressure low-temperature plasma has been applied in the dental industry, particularly for adhesives, as a surface treatment to activate the surface energy and remove contaminants. The purpose of this study was to examine the influence of atmospheric-pressure low-temperature plasma treatment on the shear bond strength between zirconia and adhesive resin cement. METHODS: The surface treatment method was classified into three groups: untreated (Cont group), alumina sandblast treatment (Sb group), and atmospheric-pressure low-temperature plasma treatment (Ps group). Adhesive resin cement was applied to stainless steel and bonded to zirconia. Shear adhesion tests were performed after complete hardening of the cement. Multiple comparisons were performed using a one-way analysis of variance and the Bonferroni method. X-ray diffractometry was used to examine the change in zirconia crystal structure. RESULTS: Statistically significant differences were noted between the control and Sb groups and between the control and Ps groups. In contrast, no statistically significant differences were noted for the Ps and Sb bond strength. Atmospheric-pressure low-temperature plasma treatment did not affect the zirconia crystal structure. CONCLUSIONS: Atmospheric-pressure low-temperature plasma treatment improves the bonding strength of adhesive resin cement as effectively as alumina sandblasting, and does not alter the zirconia crystal structure.

Carbidopa abrogates L-dopa decarboxylase coactivation of the androgen receptor and delays prostate tumor progression.

The androgen receptor (AR) plays a central role in prostate cancer progression to the castration-resistant (CR) lethal state. L-Dopa decarboxylase (DDC) is an AR coactivator that increases in expression with disease progression and is coexpressed with the receptor in prostate adenocarcinoma cells, where it may enhance AR activity. Here, we hypothesize that the DDC enzymatic inhibitor, carbidopa, can suppress DDC-coactivation of AR and retard prostate tumor growth. Treating LNCaP prostate cancer cells with carbidopa in transcriptional assays suppressed the enhanced AR transactivation seen with DDC overexpression and decreased prostate-specific antigen (PSA) mRNA levels. Carbidopa dose-dependently inhibited cell growth and decreased survival in LNCaP cell proliferation and apoptosis assays. The inhibitory effect of carbidopa on DDC-coactivation of AR and cell growth/survival was also observed in PC3 prostate cancer cells (stably expressing AR). In vivo studies demonstrated that serum PSA velocity and tumor growth rates elevated ∼2-fold in LNCaP xenografts, inducibly overexpressing DDC, were reverted to control levels with carbidopa administration. In castrated mice, treating LNCaP tumors, expressing endogenous DDC, with carbidopa delayed progression to the CR state from 6 to 10 weeks, while serum PSA and tumor growth decreased 4.3-fold and 5.4-fold, respectively. Our study is a first time demonstration that carbidopa can abrogate DDC-coactivation of AR in prostate cancer cells and tumors, decrease serum PSA, reduce tumor growth and delay CR progression. Since carbidopa is clinically approved, it may be readily used as a novel therapeutic strategy to suppress aberrant AR activity and delay prostate cancer progression.

STAT3 enhances intracellular Fas-mediated apoptotic signals in HHUA human endometrial epithelial cells.

Several endometrial signal transducer and activator of transcription 3 (STAT3)-activating cytokines are reported to be essential for blastocyst implantation, with inhibition of STAT3 activation in the endometrium also reported to prevent implantation. To investigate STAT3 signals in endometrial epithelial cells, the activation and inactivation effects of STAT3 signals were examined in the human endometrial epithelial cell line HHUA, which is thought to retain many of the intracellular signaling pathways found in normal human endometrial epithelial cells. Five STAT3-activating cytokines, IL-11, IL-10, LIF, oncostatin M and leptin, enhanced the Fas-mediated apoptosis of the HHUA cells without any increase in cell surface Fas antigen expression. STAT3 siRNA transfection suppressed STAT3 expression in HHUA cells and significantly inhibited Fas-mediated cell death. These results indicate that intracellular apoptotic signals in HHUA cells are constitutively activated and regulated by STAT3-mediated signals. This apoptosis-promoting effect of STAT3 in HHUA cells is completely different from many previous reports demonstrating anti-apoptotic effects by STAT3 activation. The STAT3 signals in HHUA cells may be specific to the human endometrial epithelial cell lineage in the regulation of blastocyst implantation.

Serotonin synthesis and metabolism-related molecules in a human prostate cancer cell line.

Prostate cancer is one of the most common tumors in males and its incidence is steadily increasing worldwide. Serotonin or 5-hydroxytryptamine (5-HT) is a well-known neurotransmitter that mediates a wide variety of physiological effects. An increase in the number of 5-HT-releasing neuroendocrine (NE) cells has been correlated with tumor progression. However, it is particularly unclear whether released 5-HT or the release of 5-HT has a role in tumor cell growth. We hypothesized that 5-HT synthesis and metabolism in NE cells regulate the growth of prostate cancer cells. In the present study, 5-HT was found to play a role as a cell growth factor in prostate cancer cells. Moreover, the pharmacological inhibition of 5-HT synthesis and metabolism interrupted the growth of prostate cancer cells. To confirm the existence of 5-HT in prostate cancer cells, we performed ELISA, HPLC, RT-PCR and immunohistochemical analyses. A high expression of tryptophan hydroxylase (TPH-1), dopa decarboxylase (DDC) and monoamine oxidase A (MAO-A) was noted in the prostate cancer cells when compared with normal prostate cells. Previous studies showed that 5-HT stimulated the proliferation of prostate cancer cells mediated by 5-HT receptors 5-HTR1A and R1B. However, cell proliferation was significantly inhibited when siRNA for both DDC and TPH-1 was transfected to the cells. Consequently, we propose that the secretion system of prostate NE cells capable of 5-HT synthesis and metabolism plays a significant role in prostate tumor generation and progression. These findings provide crucial clues for the development of potential pharmacotherapeutics to slow prostate tumor progression.

Early, H+-V-ATPase-dependent proton flux is necessary for consistent left-right patterning of non-mammalian vertebrates.

Biased left-right asymmetry is a fascinating and medically important phenomenon. We provide molecular genetic and physiological characterization of a novel, conserved, early, biophysical event that is crucial for correct asymmetry: H+ flux. A pharmacological screen implicated the H+-pump H+-V-ATPase in Xenopus asymmetry, where it acts upstream of early asymmetric markers. Immunohistochemistry revealed an actin-dependent asymmetry of H+-V-ATPase subunits during the first three cleavages. H+-flux across plasma membranes is also asymmetric at the four- and eight-cell stages, and this asymmetry requires H+-V-ATPase activity. Abolishing the asymmetry in H+ flux, using a dominant-negative subunit of the H+-V-ATPase or an ectopic H+ pump, randomized embryonic situs without causing any other defects. To understand the mechanism of action of H+-V-ATPase, we isolated its two physiological functions, cytoplasmic pH and membrane voltage (Vmem) regulation. Varying either pH or Vmem, independently of direct manipulation of H+-V-ATPase, caused disruptions of normal asymmetry, suggesting roles for both functions. V-ATPase inhibition also abolished the normal early localization of serotonin, functionally linking these two early asymmetry pathways. The involvement of H+-V-ATPase in asymmetry is conserved to chick and zebrafish. Inhibition of the H+-V-ATPase induces heterotaxia in both species; in chick, H+-V-ATPase activity is upstream of Shh; in fish, it is upstream of Kupffer's vesicle and Spaw expression. Our data implicate H+-V-ATPase activity in patterning the LR axis of vertebrates and reveal mechanisms upstream and downstream of its activity. We propose a pH- and Vmem-dependent model of the early physiology of LR patterning.

Serotonin transporter function is an early step in left-right patterning in chick and frog embryos.

The neurotransmitter serotonin has been shown to regulate a number of embryonic patterning events in addition to its crucial role in the nervous system. Here, we examine the role of two serotonin transporters, the plasma membrane serotonin transporter (SERT) and the vesicular monoamine transporter (VMAT), in embryonic left-right asymmetry. Pharmacological or genetic inhibitors of either SERT or VMAT specifically randomized the laterality of the heart and viscera in Xenopus embryos. This effect takes place during cleavage stages, and is upstream of the left-sided gene XNR-1. Targeted microinjection of an SERT-dominant negative construct confirmed the necessity for SERT function in embryonic laterality and revealed that the descendants of the right ventral blastomere are the most dependent upon SERT signaling in left-right patterning. Moreover, the importance of SERT and VMAT in laterality is conserved in chick embryos, being upstream of the early left-sided gene Shh. Endogenous transcripts of SERT and VMAT are expressed from the initiation of the primitive streak in chick and are asymmetrically expressed in Hensen's node. Taken together our data characterize two new right-sided markers in chick gastrulation, identify a novel, early component of the left-right pathway in two vertebrate species, and reveal a new biological role for serotonin transport.

Serotonin signaling is a very early step in patterning of the left-right axis in chick and frog embryos.

BACKGROUND: Consistent left-right (LR) asymmetry is a fascinating problem in developmental and evolutionary biology. Conservation of early LR patterning steps among vertebrates as well as involvement of nonprotein small-molecule messengers are very poorly understood. Serotonin (5-HT) is a key neurotransmitter with crucial roles in physiology and cognition. We tested the hypothesis that LR patterning required prenervous serotonin signaling and characterized the 5-HT pathway in chick and frog embryos. RESULTS: A pharmacological screen implicated endogenous signaling through receptors R3 and R4 and the activity of monoamine oxidase (MAO) in the establishment of correct sidedness of asymmetric gene expression and of the viscera in Xenopus embryos. HPLC and immunohistochemistry analysis indicates that Xenopus eggs contain a maternal supply of serotonin that is progressively degraded during cleavage stages. Serotonin's dynamic localization in frog embryos requires gap junctional communication and H,K-ATPase function. Microinjection of loss- and gain-of-function constructs into the right ventral blastomere randomizes asymmetry. In chick embryos, R3 and R4 activity is upstream of the asymmetry of Sonic hedgehog expression. MAO is asymmetrically expressed in the node. CONCLUSIONS: Serotonin is present in very early chick and frog embryos. 5-HT pathway function is required for normal asymmetry and is upstream of asymmetric gene expression. The microinjection data reveal asymmetry existing in frog embryos by the 4-cell stage and suggest novel intracellular 5-HT mechanisms. These functional and localization data identify a novel role for the neurotransmitter serotonin and implicate prenervous serotonergic signaling as an obligate aspect of very early left-right patterning conserved to two vertebrate species.

Asymmetric expression of Syndecan-2 in early chick embryogenesis.

Chicken Syndecan-2 (cSyndecan-2) is the homologue of Xenopus Syndecan-2, a member of the heparan sulfate proteoglycan family with an important role in left-right patterning in frog embryos. A relationship to LR asymmetry in other species has not been reported. We show that cSyndecan-2 is expressed throughout the primitive streak between st. 1 and 3 in the chick embryo, and is restricted to the rostral and caudal tips of the primitive streak at st. 4. It displays distinct left-right asymmetry, being expressed in the right side of Hensen's node at st. 5. The asymmetric expression of cSyndecan-2 is maintained around the node between st. 5 and 7. At early somite stages, somites and neural folds express cSyndecan-2. The somite expression disappears by st. 11, but strong expression in the neural tube continues. Our data reveal a new asymmetric transcript in the chick embryo and indicate that in contrast to protein-level asymmetries, which underlie syndecan-2 function in Xenopus, chick syndecan-2 exhibits asymmetry at the mRNA level.