Embryonic Pericytes Promote Microglial Homeostasis and Their Effects on Neural Progenitors in the Developing Cerebral Cortex.

Multifaceted microglial functions in the developing brain, such as promoting the differentiation of neural progenitors and contributing to the positioning and survival of neurons, have been progressively revealed. Although previous studies have noted the relationship between vascular endothelial cells and microglia in the developing brain, little attention has been given to the importance of pericytes, the mural cells surrounding endothelial cells. In this study, we attempted to dissect the role of pericytes in microglial distribution and function in developing mouse brains. Our immunohistochemical analysis showed that approximately half of the microglia attached to capillaries in the cerebral walls. Notably, a magnified observation of the position of microglia, vascular endothelial cells and pericytes demonstrated that microglia were preferentially associated with pericytes that covered 79.8% of the total capillary surface area. Through in vivo pericyte depletion induced by the intraventricular administration of a neutralizing antibody against platelet-derived growth factor receptor (PDGFR)ß (clone APB5), we found that microglial density was markedly decreased compared with that in control antibody-treated brains because of their low proliferative capacity. Moreover, in vitro coculture of isolated CD11b+ microglia and NG2+PDGFRα- cells, which are mostly composed of pericytes, from parenchymal cells indicated that pericytes promote microglial proliferation via the production of soluble factors. Furthermore, pericyte depletion by APB5 treatment resulted in a failure of microglia to promote the differentiation of neural stem cells into intermediate progenitors. Taken together, our findings suggest that pericytes facilitate microglial homeostasis in the developing brains, thereby indirectly supporting microglial effects on neural progenitors.SIGNIFICANCE STATEMENT This study highlights the novel effect of pericytes on microglia in the developing mouse brain. Through multiple analyses using an in vivo pericyte depletion mouse model and an in vitro coculture study of isolated pericytes and microglia from parenchymal cells, we demonstrated that pericytes contribute to microglial proliferation and support microglia in efficiently promoting the differentiation of neural stem cells into intermediate progenitors. Our present data provide evidence that pericytes function not only in the maintenance of cerebral microcirculation and blood brain barrier (BBB) integrity but also in microglial homeostasis in the developing cerebral walls. These findings will expand our knowledge and help elucidate the mechanism of brain development both in healthy and disease conditions.

Roles of lipocalin-type and hematopoietic prostaglandin D synthases in mouse retinal angiogenesis.

Normal angiogenesis is essential for retinal development and maintenance of visual function in the eye, and its abnormality can cause retinopathy and other eye diseases. Prostaglandin D2 is an anti-angiogenic lipid mediator produced by lipocalin-type PGD synthase (L-PGDS) or hematopoietic PGD synthase (H-PGDS). However, the exact role of these PGD synthases remains unclear. Therefore, we compared the roles of these synthases in murine retinal angiogenesis under physiological and pathological conditions. On postnatal day (P) 8, the WT murine retina was covered with an elongated vessel. L-PGDS deficiency, but not H-PGDS, reduced the physiological vessel elongation with sprouts increase. L-PGDS expression was observed in endothelial cells and neural cells. In vitro, L-PGDS inhibition increased the hypoxia-induced vascular endothelial growth factor expression in isolated endothelial cells, inhibited by a prostaglandin D2 metabolite, 15-deoxy-Δ12,14 -PGJ2 (15d-PGJ2) treatment. Pericyte depletion, using antiplatelet-derived growth factor receptor-ß antibody, caused retinal hemorrhage with vessel elongation impairment and macrophage infiltration in the WT P8 retina. H-PGDS deficiency promoted hemorrhage but inhibited the impairment of vessel elongation, while L-PGDS did not. In the pericyte-depleted WT retina, H-PGDS was expressed in the infiltrated macrophages. Deficiency of the D prostanoid receptor also inhibited the vessel elongation impairment. These results suggest the endogenous role of L-PGDS signaling in physiological angiogenesis and that of H-PGDS/D prostanoid 1 signaling in pathological angiogenesis.

Proportion of Japanese outpatients filling prescriptions for long-term medication regimens.

Aim: Our study aimed to clarify how long outpatients with chronic diseases such as hypertension continuously fill prescriptions for the same medications as those prescribed initially and how many medications they take over the long term. Methods: Medication records from April 1, 2016 to March 31, 2017 with total days between initial and final dispensation date ≥330 days and total days of medication supplies ≥180 days were extracted from an electronic database in a Japanese community pharmacy chain. The continuity of refilling medications over 1 year (ie, medication fill adherence) was measured using the medication possession ratio (MPR). Results: A total of 34,549 outpatients received long-term medications under the above conditions (4.4% of all patients in the database). Mean age was 66.0±17.4 years; 63.1% were ≥65 years. The mean number of medications prescribed per patient was 3.2±2.3. More than one-fifth of patients (22.6%) were taking ≥5 medications. The mean MPR for patients overall was 93.6±11.2%; 87.2% of patients had an MPR ≥80% but <110%. Amlodipine besylate, an antihypertensive, was the most commonly prescribed drug (n=5,537 patients). Conclusion: Outpatients that received long-term medications with no change in prescription had an MPR >90% for around 3 medications. It can be reasonably assumed that these patients could receive a longer-term medication supply with the partial fills based on a physician's instruction ("Bunkatu Chozai" in Japanese). This longer-term supply would be similar to a basic prescription refill, but would require a physician's signature allowing for partial refills rather than a new prescription for each refill.

Inhibition of stromal cell-derived factor-1α/CXCR4 signaling restores the blood-retina barrier in pericyte-deficient mouse retinas.

In diabetic retinopathy (DR), pericyte dropout from capillary walls is believed to cause the breakdown of the blood-retina barrier (BRB), which subsequently leads to vision-threatening retinal edema. While various proinflammatory cytokines and chemokines are upregulated in eyes with DR, their distinct contributions to disease progression remain elusive. Here, we evaluated roles of stromal cell-derived factor-1α (SDF-1α) and its receptor CXCR4 in the BRB breakdown initiated by pericyte deficiency. After inhibition of pericyte recruitment to developing retinal vessels in neonatal mice, endothelial cells (ECs) upregulated the expression of SDF-1α. Administration of CXCR4 antagonists, or EC-specific disruption of the CXCR4 gene, similarly restored the BRB integrity, even in the absence of pericyte coverage. Furthermore, CXCR4 inhibition significantly decreased both the expression levels of proinflammatory genes (P < 0.05) and the infiltration of macrophages (P < 0.05) into pericyte-deficient retinas. Taken together, EC-derived SDF-1α induced by pericyte deficiency exacerbated inflammation through CXCR4 in an autocrine or paracrine manner and thereby induced macrophage infiltration and BRB breakdown. These findings suggest that the SDF-1α/CXCR4 signaling pathway may be a potential therapeutic target in DR.

Sustained inflammation after pericyte depletion induces irreversible blood-retina barrier breakdown.

In the central nervous system, endothelial cells (ECs) and pericytes (PCs) of blood vessel walls cooperatively form a physical and chemical barrier to maintain neural homeostasis. However, in diabetic retinopathy (DR), the loss of PCs from vessel walls is assumed to cause breakdown of the blood-retina barrier (BRB) and subsequent vision-threatening vascular dysfunctions. Nonetheless, the lack of adequate DR animal models has precluded disease understanding and drug discovery. Here, by using an anti-PDGFRß antibody, we show that transient inhibition of the PC recruitment to developing retinal vessels sustained EC-PC dissociations and BRB breakdown in adult mouse retinas, reproducing characteristic features of DR such as hyperpermeability, hypoperfusion, and neoangiogenesis. Notably, PC depletion directly induced inflammatory responses in ECs and perivascular infiltration of macrophages, whereby macrophage-derived VEGF and placental growth factor (PlGF) activated VEGFR1 in macrophages and VEGFR2 in ECs. Moreover, angiopoietin-2 (Angpt2) upregulation and Tie1 downregulation activated FOXO1 in PC-free ECs locally at the leaky aneurysms. This cycle of vessel damage was shut down by simultaneously blocking VEGF, PlGF, and Angpt2, thus restoring the BRB integrity. Together, our model provides new opportunities for identifying the sequential events triggered by PC deficiency, not only in DR, but also in various neurological disorders.

Analysis of spontaneous inquiries about suspected adverse drug reactions posted by the general public on the electronic Japanese bulletin board "Yahoo! Japan Chiebukuro".

PURPOSE: Spontaneous inquiries about the development of adverse drug reactions (ADRs) to medicines can be extracted based on the questions posted by the general public on the electronic Japanese bulletin board "Yahoo! Japan Chiebukuro". Our aim was to clarify the characteristics related to people's descriptions of suspected ADRs and determine the reasons for submitting a spontaneous inquiry. METHODS: Fifty brand names of medicines used for inquiry extraction were chosen by selecting 35 pharmaceutical products, based on the generic names that had the highest sales in Japan. Questions containing both the brand name of one of these medicines and the term "Fukusayo" (ADR in Japanese) that were posted from July 2004 to June 2009 were extracted from the site. RESULTS: Among 1,419 questions extracted, 614 questions had at least one identifiable brand name of a suspected medicine, an ADR description, and the extent to which the ADR appeared to be caused by the suspected medicine(s). Among these 614 questions, 589 described in detail the symptoms/signs that the inquirers themselves or their families had experienced as ADRs. The highest number of questions was found for Paxil (525). Posts asking whether the symptoms being experienced were due to an ADR accounted for the highest number of questions. In most cases, the inquirer suspected that a single medicine led to an ADR and was seeking advice from others taking the same medicine. CONCLUSION: Our examination of spontaneous inquiries showed that people have sufficient knowledge to adequately report potential ADRs in terms of their symptoms, suspected medicines, and the disease for which the medicine was used. However, they often did not describe the start time when the ADR appeared or when the suspected medicine was started.

Assessment of Assistance in Smoking Cessation Therapy by Pharmacies in Collaboration with Medical Institutions- Implementation of a Collaborative Drug Therapy Management Protocol Based on a Written Agreement between Physicians and Pharmacists.

This study built a protocol for drug therapy management (hereinafter "the protocol") that would enable continuous support from the decision making of smoking cessation therapy to the completion of therapy through the collaboration of physicians and community pharmacists, after which we evaluated whether the use of this protocol would be helpful to smoking cessation therapy. This study utilized the "On the Promotion of Team-Based Medical Care", a Notification by the Health Policy Bureau as one of the resources for judgment, and referred to collaborative drug therapy management (CDTM) in the United States. After the implementation of this protocol, the success rate of smoking cessation at the participating medical institutions rose to approximately 70%, approximately 28-point improvement compared to the rate before the implementation. In addition to the benefits of the standard smoking cessation program, this result may have been affected by the intervention of pharmacists, who assisted in continuing cessation by advising to reduce drug dosage as necessary approximately one week after the smoking cessation, when side effects and the urge to smoke tend to occur. Additionally, the awareness survey for the intervention group revealed that all respondents, including patients who failed to quit smoking, answered that they were satisfied to the question on general satisfaction. The question about the reason for successful cessation revealed that the support by pharmacists was as important as, or more important than, that by physicians and nurses. This infers that the pharmacists' active engagement in drug therapy for individual patients was favorably acknowledged.

Chiral separation with novel (S)-biotin-bonded silica gel for liquid chromatography.

Liquid chromatographic separation of enantiomers was accomplished using a chiral stationary phase (CSP) derived from (S)-biotin on silica gel. In both nonaqueous and aqueous media, this CSP (1) permitted separation of racemic amino acid derivatives based on hydrogen bonding with a urea moiety of the biotin moiety.

Enantiomer separation by reversed-phase liquid chromatography with novel hydrophobic phases composed of chiral cationic surfactants.

This paper describes enantiomer separation using four kinds of chiral stationary phases (CSPs) where quaternary ammonium surfactants containing L-valine diamide moieties into long alkyl chains were bound to silicagel supports by reversed phase liquid chromatography. Our aim was to examine hydrogen bonding association of the chiral moiety in hydrophobic phase brought about by aggregation of the micelle-forming surfactants on the surface. The following CSPs were thus derived from the vinyl-terminated chiral surfactants via hydrosilylation: CSP 1 from N-[3-(10-undecenoyl-L-valylamino)propyl]-N,N,N-trimethylammonium bromide, CSP 2 from N-[6-(10-undecenoyl-L-valylamino)hexyl]-N,N,N-trimethyl-ammonium bromide, CSP 3 from N-[3-(10-undecenoyl-L-valylamino)propyl]-N-octadecanyl-N,N-dimethyl-ammonium bromide and CSP 4 from N-[6-(10-undecenoyl-L-valylamino)hexyl]-N-octadecanyl-N,N-dimethylammonium bromide. The degree of hydrophobicity in the interfacial phase was observed by measuring pyrene fluorescence in aqueous media including an organic modifier. Retention of racemic N-acylleucine isopropyl esters was highest in CSP 4, followed by 3, 2, and 1. Largest alpha values toward enantiomer separation were observed for CSP 4 where the chiral moieties were kept through a hexamethylene unit apart from the polar head groups and to which another long alkyl chain was attached, as compared with those for CSP 4. In CSP 4, the chiral moiety to interact with enantiomeric solutes should be buried into the interfacial phase deeply in more extent than CSP 3. In a similar manner, CSP 2 has more effective for enantiomer separation than CSP 1. The interfacial phase of these CSPs was easily exposed to the bulk phase because of the affinity between the bulk phase and the polar head groups as well as their electrostatic repulsion. However, degree of the enantiomer separation can be controlled by the depth of the chiral moiety in the hydrophobic interfacial phase.

A prescription survey about combined use of acetylcholinesterase inhibitors and anticholinergic medicines in the dementia outpatient using electronic medication history data from community pharmacies.

PURPOSE: We investigated prescriptions regarding the combined use of donepezil hydrochloride (DPZ) and anticholinergics for elderly outpatients in Japan to determine the impact that combination therapy has on decreasing their cognitive functions. METHODS: Using electronic medication records from 142 community pharmacies, outpatients older than 40 years of age taking DPZ, with or without other prescription medicines, were assessed over 6 years, beginning in 2007. We estimated the number of medicines administered along with DPZ, the number of anticholinergics administered along with DPZ, and the medicines' anticholinergic cognitive burden (ACB) scale cumulative score based on data from the top four pharmacies that filled the highest number of prescriptions for DPZ for outpatients with dementia in 2010. Data were gathered from records of 431 patients; only three patients were younger than 60 years. RESULTS: There was a 1.94-fold increase in the number of prescriptions including DPZ over 6 years. The proportion of patients to whom other medicines were administered along with DPZ was 65.6% (n=283) and the proportion of those taking at least one anticholinergic agent was 24.1% (n=104). The mean number of medicines among subjects taking at least one anticholinergic was 5.7, and the mean cumulative ACB score for anticholinergics contained in these medicines was 2.6. Among 104 patients to whom the anticholinergics were administered along with DPZ, two outpatients taking urologic medicines such as oxybutynin hydrochloride or tolterodine tartrate were found. CONCLUSION: Our findings suggest that it is necessary to pay attention to a decline in cognitive function when prescribing multiple medicines, especially to elderly patients who have already been prescribed DPZ.

Enantiomeric separation using temperature-responsive chiral polymers composed of L-valine diamide derivatives in aqueous liquid chromatography.

This paper describes enantiomer separation by aqueous liquid chromatography using chiral stationary phases (CSPs) in which temperature-responsive polymers derived from acryloyl-L-valine N-methylamide (1) and its N,N-dimethylamide analogue (2) were bound on silica gel supports. The linear polymers composed of monomer 1 and monomer 2 are temperature-responsive in solution and their aggregation and extension states related to water solubility are reversible at particular critical temperatures. During chromatography, enantioselectivity and retentivity for solute enantiomers were controlled by column temperature, which changes the aggregation and extension states of the chiral polymers depending upon their interior hydrophobic nature. Two different types of CSPs were made: a temperature-responsive linear polymer derived from 3-mercaptopropyl silica gel, and another polymer cross-linked with ethylene dimethacrylate from 3-methacryloyloxypropyl silica gel. The former CSP could separate racemic N-(3,5-dinitrobenzoyl(DNB))amino acid isopropyl esters. Retention of the amino acid derivatives was prolonged with an increase in column temperature. Enantioselectivity was also enhanced with temperature increase until the particular critical temperature. The latter, cross-linked CSP could not provide enantioselectivity for the amino acid derivatives in aqueous media, although the chiral valine diamide moieties were effective for enantiomer separation in non-aqueous media. The degree of hydrophobicity and volume of the bonded phase formed by the polymers on the support surface was determined by measuring the fluorescence of pyrene.

Chiral separation of enantiomeric 1,2-diamines using molecular imprinting method and selectivity enhancement by addition of achiral primary amines into eluents.

The imprinted polymers based on a transient complex formation between methacrylic acid and template molecules were prepared by using methacrylic acid and ethylene dimethacrylate as a cross-linking agent. The template molecules used were (R,R)-cyclohexanediamine (1), (S,S)-1,2-diphenylethylenediamine (2) and (S)-1,1'-binaphthyl-2,2'-diamine (3). Another group of templates were those in which the amino group of these templates had been substituted by the hydroxy group: (R,R)-1,2-cyclohexanediol (4) and (S,S)-hydrobenzoin (5). Racemic 2 was separated by the polymer prepared with template 2 (P2) and that with template 1 (P1). Template 2 is larger than template 1 in steric bulkiness, but P1 was effective for the enantiomer separation of racemic 2. P1 was not effective for the separation of racemic 4. Enantioselectivity observed in racemic 2 in P2 was higher than that in racemic 1 in P1. P2 has no definite predetermined shape for solute 1, but it was capable of separating racemic 1. This separation should be thus ascribed to the orientation of at least two carbonyl groups reflecting the conformation of template 2 in P2 cavity. Racemic 5, having the same configuration of the two bulky phenyl groups as that of solute 2, was separated in P2. When the primary amines such as propylamine, cyclohexylamine and 1-adamantanamine were added into the acetic acid-methanol mixtures as eluents, both enantioselectivity and retentivity for racemic 2 were enhanced along with the remarkable peak tailing.

[Effects of excess nicotinic acid on growth and the urinary excretion of B-group vitamins and the metabolism of tryptophan in weaning rats].

To determine the tolerable upper intake level of nicotinic acid in humans, we investigated the effects of excess nicotinic acid administration on body weight gain, food intake, and urinary excretion of water-soluble vitamins and the metabolism of tryptophan in weaning rats. The weaning rats were freely fed a niacin-free 20% casein diet (control diet) or the same diet with 0.1%, 0.3% or 0.5% nicotinic acid for 23 days. The excess nicotinic acid intake did not affect body weight gain, food intake, serotonin contents in the brain, stomach and small intestine, or the urinary excretions of water-soluble vitamins. Although excess nicotinic acid did not affect the upper part of the tryptophan-nicotinamide pathway, 0.5% nicotinic acid diet increased the urinary excretion of quinolinic acid. The diet containing more than 0.3% nicotinic acid also increased the urinary excretion of nicotinic acid, which is usually below the limit of detection. As determined from the results of body weight gain and food intake as indices for apparent adverse effects, the no-observed-adverse-effect-level (NOAEL) for nicotinic acid was 0.5% in diet, corresponding to 450 mg/kg body weight/day. As judged from in increase of urinary quinolinic acid and nicotinic acid as indices of metabolic change, NOAEL was 0.1% in diet, corresponding to 90 mg/kg body weight/day, and the lowest-observed-adverse-effect-level (LOAEL) was 0.3% in diet, corresponding to 270 mg/kg body weight/day.