GLP-1 derivatives with functional sequences transit and migrate through trigeminal neurons.

Patients with dementia are increasing with the aging of the population, and dementia has become a disease with high unmet medical needs. Glucagon-like peptide-1 (GLP-1), a neuropeptide, has been reported to improve learning and memory following intracerebroventricular administration. We focused on intranasal administration, which can deliver drugs noninvasively and efficiently to the brain. Although much of the human nasal mucosa is occupied by respiratory epithelium, many capillaries are present in the paracellular route of respiratory epithelium. Therefore, to incorporate GLP-1 into cells, we created a GLP-1 derivative by adding cell-penetrating peptides (CPP) and penetration accelerating sequences (PAS) to GLP-1. We investigated in vitro and in vivo function of PAS-CPP-GLP-1 to enable the translocation of GLP-1 directly from nose to brain. PAS-CPP-GLP-1 enhanced cellular uptake by macropinocytosis with CPP, efficiently escaped from the endosomes due to PAS, and exited the cells. PAS-CPP-GLP-1 also transited trigeminal nerve cells through axon transport and migrated to the adjacent trigeminal nerve cell. Moreover, PAS-CPP-GLP-1 showed significant improvement in learning memory in mice within 20 min of intranasal administration. These results suggested CPP and PAS may be important for the efficient transfer of GLP-1 to the site of action in the brain following intranasal administration.

Characterization of a spontaneous mouse model of mild, accelerated aging via ECM degradation in emphysematous lungs.

Emphysema limits airflow and causes irreversible progression of chronic obstructive pulmonary disease (COPD). Strain differences must be considered when selecting mouse models of COPD, owing to disease complexity. We previously reported that a novel C57BL/6JJcl substrain, the Mayumi-Emphysema (ME) mouse, exhibits spontaneous emphysema; however, the other characteristics remain unknown. We aimed to characterize the lungs of ME mice and determine their experimental availability as a model. ME mice had a lower body weight than the control C57BL/6JJcl mice, with a median survival time of ~80 weeks. ME mice developed diffused emphysema with respiratory dysfunction from 8 to 26 weeks of age, but did not develop bronchial wall thickening. Proteomic analyses revealed five extracellular matrix-related clusters in downregulated lung proteins in ME mice. Moreover, EFEMP2/fibulin-4, an essential extracellular matrix protein, was the most downregulated protein in the lungs of ME mice. Murine and human EFEMP2 were detected in the pulmonary artery. Furthermore, patients with mild COPD showed decreased EFEMP2 levels in the pulmonary artery when compared to those without COPD. The ME mouse is a model of mild, accelerated aging with low-inflammatory emphysema and respiratory dysfunction that progresses with age and pulmonary EFEMP2 decrease, similar to that observed in patients with mild COPD.

Intracellular Drug Delivery Process of Am80-Encapsulated Lipid Nanoparticles Aiming for Alveolar Regeneration.

Chronic obstructive pulmonary disease (COPD) results in obstructive ventilatory impairment caused by emphysema, and current treatment is limited to symptomatic therapy or lung transplantation. Therefore, the development of new treatments to repair alveolar destruction is especially urgent. Our previous study revealed that 1.0 mg/kg of synthetic retinoid Am80 had a repair effect on collapsed alveoli in a mouse model of elastase-induced emphysema. From these results, however, the clinical dose calculated in accordance with FDA guidance is estimated to be 5.0 mg/60 kg, and it is desirable to further reduce the dose to allow the formulation of a powder inhaler for clinical application. To efficiently deliver Am80 to the retinoic acid receptor in the cell nucleus, which is the site of action, we focused on SS-cleavable proton-activated lipid-like material O-Phentyl-P4C2COATSOME®SS-OP, hereinafter referred to as "SS-OP"). In this study, we investigated the cellular uptake and intracellular drug delivery process of Am80-encapsulated SS-OP nanoparticles to elucidate the mechanism of Am80 by nanoparticulation. Am80-encapsulated SS-OP nanoparticles were taken up into the cells via ApoE, and then Am80 was efficiently delivered into the nucleus via RARα. These results indicated the usefulness of SS-OP nanoparticles as drug delivery system carriers of Am80 for COPD treatment.

Involvement of trigeminal axons in nose-to-brain delivery of glucagon-like peptide-2 derivative.

In our previous study, we created a glucagon-like peptide-2 (GLP-2) derivative with the functional sequence PAS-CPP to achieve efficient uptake by the respiratory epithelium and trigeminal nerve. By using octaarginine for cell penetrating peptides (CPP) and FFLIPKG, a reverse sequence of a part of the cathepsin D sequence for the penetration accelerating sequence (PAS), we found that the derivative was taken up by the cells through macropinocytosis and efficiently escaped from the endosomes and exited the cells. Moreover, it showed drug effects by intranasal (in.) administration at the same dose as intracerebroventricular (icv.) administration, which is direct drug administration into the brain. The purpose of this study was to elucidate the cause of the drug effect of in. administered PAS-CPP-GLP-2 at the same dose as that by icv. administration. The present results suggested that although icv. administered PAS-CPP-GLP-2 entered the cerebrospinal fluid, it barely penetrated the perivascular space of the brain, and therefore, only a small amount of the administered dose may have reached the site of action in the brain. In contrast, it was qualitatively suggested that in. administered PAS-CPP-GLP-2 migrates from the trigeminal nerve to the central nervous system via the principal sensory trigeminal nucleus and then through the trigeminal lemniscus. The present results show that nose-to-brain delivery by trigeminal axons, which is assumed to be a transcellular pathway, may be possible. As the drug can be delivered into the nerve, it is expected to be applied not only as a central delivery route but also for the treatment of neurological diseases.

A Mouse Model for Tuberculosis Combined With Inhalable Imiquimod-PLGA Nanocomposite Particles Based on Macrophage Phenotype.

BACKGROUND/AIM: In vivo models of tuberculosis are effective tools for developing new drugs. The objective of this study was to prepare in vivo models for tuberculosis by utilizing nanocomposite particles (NCPs) containing imiquimod-loaded poly(lactic-co-glycolic acid) nanoparticles. MATERIALS AND METHODS: NCPs were prepared from dichloromethane with imiquimod and poly(lactic-co-glycolic acid) using a spray dryer. Mice were treated with NCPs in the lungs by inhalation, and then infection with Mycobacterium bovis bacille Calmette-Guerin was performed (treatment groups). The concentrations of the pro-inflammatory cytokines, tumor necrosis factor-α and interferon-γ were measured in bronchoalveolar lavage fluid using an enzyme-linked immunosorbent assay. RESULTS: When animals were treated with NCPs, the concentrations of tumor necrosis factor-α and interferon-γ in bronchoalveolar lavage fluid were significantly higher than in animals not treated with NCPs. In addition, high bacterial counts and circular granuloma were observed. CONCLUSION: NCPs prepared in this study enhanced the level of inflammation in the lungs and support the preparation of in vivo models of tuberculosis.

Intracerebroventricular administration of oxytocin and intranasal administration of the oxytocin derivative improve ß-amyloid peptide (25-35)-induced memory impairment in mice.

AIM: We previously reported that oxytocin, a peptide hormone, can reverse the ß-amyloid peptide (25-35) (Aß25-35 )-induced impairments of the murine hippocampal synaptic plasticity. In this study, we examined the effects of oxytocin on the Aß25-35 -induced impairment of cognitive behavior in murine in order to investigate the potential of oxytocin as a clinical treatment tool for Alzheimer's disease (AD). METHODS: The Y-maze and Morris water maze (MWM) tests were performed. Since the intracerebroventricular (ICV) administration is both invasive and impractical, we further utilized intranasal (IN) delivery to the brain. For this purpose, we prepared an oxytocin derivative containing cell-penetrating peptides and a penetration accelerating sequence, which was subsequently used in our IN administration experiments. RESULTS: We herein showed that the ICV administration of oxytocin in mice exerted memory-improving effects on the Aß25-35 -induced amnesia in both the Y-maze and MWM tests. The IN administration of the oxytocin derivative exhibited memory-improving effects in the Y-maze test. Moreover, we acquired evidence that the fluorescein isothiocyanate-labeled oxytocin derivative was distributed throughout the mouse brain following its IN administration. CONCLUSION: Our results suggest that the oxytocin derivative is effective for its IN delivery to the brain and may be particularly useful in the clinical treatment of cognitive impairment, such as that characterizing AD.

Radiolabeling Method for Lyophilizate for Dry Powder Inhalation Formulations.

Human lung deposition data is non-mandatory for drug approval but very useful for the development of orally inhaled drug products. Lung deposition of inhaled drugs can be quantified by radionuclide imaging, for which one of the first considerations is the method used to radiolabel formulations. In this study, we report the development of a radiolabeling method for lyophilizate for dry powder inhalation (LDPI) formulations. TechneCoatTM is one method that can radiolabel drug particles without using solvents. In this method, particles are radiolabeled with a dispersion of 99mTc-labeled nanoparticles called TechnegasTM. Because a LDPI formulation is not comprised of particles but is a lyophilized cake aerosolized by air impact, the TechneCoat method cannot be used for the radiolabeling of LDPI formulations. We therefore modified the TechneCoat apparatus so that LDPI formulations were not aerosolized by the Technegas flow. Radiolabeling using a modified TechneCoat apparatus was validated with model LDPI formulations of interferon alpha (IFN). IFN of 99mTc-unlabeled, IFN of 99mTc-labeled, and 99mTc of 99mTc-labeled LDPI formulations showed similar behavior, and differences from IFN of 99mTc-unlabeled LDPI formulations were within ±15% in aerodynamic particle size distribution measurement. Our radiolabeling method for LDPI formulations may be useful for the quantification of drug deposition in human lungs.

Am80-Encapsulated Lipid Nanoparticles, Developed with the Aim of Achieving Alveolar Regeneration, Have an Improvement Effect on Pulmonary Emphysema.

Chronic obstructive pulmonary disease (COPD) is characterized by chronic bronchitis and emphysema, and current drug treatments target its symptoms. Thus, the development of a therapeutic drug to repair alveolar destruction is urgently needed. Our previous research revealed that the synthetic retinoic acid Am80 (1.0 mg/kg) showed a repairing effect on collapsed alveoli in a mouse model of elastase-induced emphysema. However, a further reduction in the dose is desirable to facilitate the development of a powder inhalation formulation for clinical application. We, therefore, focused on SS-OP to deliver Am80 efficiently. As a result, 0.01 mg/kg of Am80-encapsulated SS-OP nanoparticles repaired collapsed alveoli and improved the respiratory function in the mouse model of elastase induced emphysema. The results suggested that, with the use of SS-OP, the Am80 dose could be reduced. This could contribute to the development of a powder inhalation system as a curative medicine for COPD.

Usefulness of cell-penetrating peptides and penetration accelerating sequence for nose-to-brain delivery of glucagon-like peptide-2.

Neuropeptides are expected as therapeutic drug candidates for central nervous system (CNS) disorders. Intracerebroventricular (i.c.v.) administration of glucagon-like peptide-2 (GLP-2) has an antidepressant-like effect not only in depression model mice but also in treatment-resistant depression model mice. However, because i.c.v. administration is very invasive, research is progressing on brain delivery using intranasal administration as a non-invasive method. After intranasal administration of the drug, there are two routes to the brain. That of direct delivery from the paracellular route of olfactory epithelium to the brain via the olfactory bulb has been studied, and that of systemic absorption via the paracellular route of respiratory epithelium has been put to practical use. The high degree of vascularization and permeability of the nasal mucosa enables drug delivery via the paracellular route that leads to systemic delivery. Therefore, suppressing systemic absorption may increase drug delivery to brain, so we focused on the transcellular route. We created a GLP-2 derivative by adding cell-penetrating peptides (CPP) and penetration accelerating sequences (PAS), which are reported to provide efficient intracellular uptake, to GLP-2. However, to deliver GLP-2 by the transcellular route, GLP-2 must not only be taken up into cells but also move out of the cells. We investigated in vitro and in vivo function of PAS-CPP-GLP-2 to enable the translocation of GLP-2 directly from the nose to the brain. Derivatization of PAS-CPP-GLP-2 prevented its degradation. In the evaluation of intracellular dynamics, PAS-CPP-GLP-2 enhanced cellular uptake by macropinocytosis with CPP and promoted escape from endosomal vesicles by PAS. This study also showed that PAS-CPP-GLP-2 can move out of cells. Furthermore, only this PAS-CPP-GLP-2 showed an antidepression-like effect within 20 min of intranasal administration. Intranasal administered PAS-CPP-GLP-2 surprisingly showed the effect at the same dose with i.c.v. administration, but intravenous administered PAS-CPP-GLP-2 did not show the effect. These results suggested that PAS-CPP-GLP-2 can be efficiently delivered from the nose to the CNS and show a pharmacological effect, demonstrating the usefulness of PAS and CPP for nose-to-brain delivery of GLP-2.

Optimization of Very Low-Dose Formulation of Vitamin D3 with Lyophilizate for Dry Powder Inhalation System by Simple Method Based on Time-of-Flight Theory.

It has been previously reported that active vitamin D3 (VD3) is a candidate drug that can repair alveolar damage in chronic obstructive pulmonary disease at a very low dose. We herein report the optimization of a very low-dose formulation of VD3 for dry powder inhalation by a simple method based on time-of-flight (TOF) theory. As the preparation content of VD3 is very low, aerodynamic particle size distribution cannot be measured by pharmacopeial methods that require quantification of the main drug. Thus, a simple method based on TOF theory, which can measure aerodynamic particle size distribution without quantification, was used. The optimized formulation for an inhalation system using a lyophilized cake contained phenylalanine as the excipient (VD3 1 µg/vial + phenylalanine 0.3 mg/vial) and showed high performance with fine particle fraction ≤ 3 µm = 47.2 ± 4.4%. The difference between the results of pharmacopeial methods and simple method was examined using the formulation containing 10 µg/vial of VD3 and was within 5.0%. The preparation is expected to efficiently deliver VD3 to the lungs. Our simple method can optimize dry powder inhalation formulations more easily and rapidly even when the content of the main drug in a preparation is very low.

Electrophysiological and Pathological Impact of Medium-Dose External Carbon Ion and Proton Beam Radiation on the Left Ventricle in an Animal Model.

Background Medium-dose (25 gray) x-ray radiation therapy has recently been performed on patients with refractory ventricular tachyarrhythmias. Unlike x-ray, carbon ion and proton beam radiation can deliver most of their energy to the target tissues. This study investigated the electrophysiological and pathological changes caused by medium-dose carbon ion and proton beam radiation in the left ventricle (LV). Methods and Results External beam radiation in the whole LV was performed in 32 rabbits. A total of 9 rabbits were not irradiated (control). At the 3-month or 6-month follow-up, the animals underwent an open-chest electrophysiological study and were euthanized for histological analyses. No acute death occurred. Significant LV dysfunction was not seen. The surface ECG revealed a significant reduction in the P and QRS wave voltages in the radiation groups. The electrophysiological study showed that the local conduction times in each LV site were significantly longer and that the local LV bipolar voltages were significantly lower in the radiation groups than in the control rabbits. Histologically, apoptosis, fibrotic changes, and a decrease in the expression of the connexin 43 protein were seen in the LV myocardium. These changes were obvious at 3 months, and the effects were sustained 6 months after radiation. No histological changes were seen in the coronary artery and esophagus, but partial radiation pneumonitis was observed. Conclusions Medium-dose carbon ion and proton beam radiation in the whole LV resulted in a significant electrophysiological disturbance and pathological changes in the myocardium. Radiation of the arrhythmogenic substrate would modify the electrical status and potentially induce the antiarrhythmic effect.

Circulating intermediate monocytes and atrial structural remodeling associated with atrial fibrillation recurrence after catheter ablation.

BACKGROUND: Inflammation, such as that associated with intermediate CD14++ CD16+ monocytes and atrial structural remodeling (SRM), may be important in the recurrence of atrial fibrillation (AF) after catheter ablation. However, the relationship between the intermediate CD14++ CD16+ monocytes, SRM, and AF recurrence is unclear. METHODS: Twenty-four patients with AF were enrolled. The proportion of intermediate monocytes (PIM) was assessed before ablation by flow cytometry. As a surrogate marker of SRM, the volume ratio (VR) of signal intensity greater than 1 standard deviation on late-gadolinium enhancement magnetic resonance imaging (LGE-MRI) was calculated. We investigated whether PIM correlated with SRM on LGE-MRI and determined the optimal cutoff value for predicting AF recurrence. RESULTS: Univariate analysis revealed positive correlations between PIM and BNP with SRM (PIM: r = .593, p = .002; BNP: r = .567, p = .004). Multivariable analysis revealed that PIM was independently associated with VR on LGE-MRI (ß = .522; p = .033). The finding of an area under the receiver operating characteristic curve of 0.750 revealed that a VR ≥ 13.3% on LGE-MRI as the optimal cutoff value to predict AF recurrence with 80% sensitivity and 71% specificity, which was associated with PIM ≥ 10.0%. CONCLUSION: Intermediate monocytes were significantly positively correlated with SRM. PIM ≥ 10% was associated with a VR ≥ 13.3% on LGE-MRI, which predicted AF recurrence after catheter ablation.

Feasibility of catheter ablation in patients with persistent atrial fibrillation guided by fragmented late-gadolinium enhancement areas.

BACKGROUND: A computer simulation model has demonstrated that atrial fibrillation (AF) driver can be attached to heterogeneous fibrosis assessed by late gadolinium enhancement magnetic resonance imaging (LGE-MRI). However, it has not been well elucidated in patients with persistent AF. The aim of this study was to investigate whether radiofrequency (RF) applications in the fragmented LGE area (FLA) could terminate AF or convert it to atrial tachycardia (AT) and improve the rhythm outcome. METHODS: A total of 31 consecutive persistent AF patients with FLAs were enrolled (FLA ablation group, mean age: 69 ± 8 years, mean left atrial diameter: 42 ± 6 mm). A favorable response was defined as direct AF termination or AT conversion during RF applications at the FLA. The rhythm outcome was compared between the FLA ablation group and FLA burden-matched pulmonary vein isolation (PVI) group. RESULTS: Favorable responses were found in 15 (48%) of 31 patients in the FLA group (AF termination in seven, AT conversion in eight patients), but not in the PVI group. AF recurrence at 12 months follow-up was significantly less in the FLA ablation group than in the PVI group (4 [13%] vs. 12 [39%] of 31 patients, log-rank p = .023). In patients with a favorable response, AT recurred in 1 (7%) of 15 patients, but AF did not. CONCLUSIONS: FLA ablation could terminate AF or convert it to AT in half of the patients. No AF recurrence was documented in patients with a favorable response.

Late-gadolinium enhancement properties associated with atrial fibrillation rotors in patients with persistent atrial fibrillation.

BACKGROUND: A computational model demonstrated that atrial fibrillation (AF) rotors could be distributed in patchy late-gadolinium enhancement (LGE) areas and play an important role in AF drivers. However, this was not validated in humans. OBJECTIVE: The purpose of this study was to evaluate the LGE properties of AF rotors in patients with persistent AF. METHODS: A total of 287 segments in 15 patients with persistent AF (long-standing persistent AF in 9 patients) that underwent AF ablation were assessed. Non-passively activated areas (NPAs), where rotational activation (AF rotor) was frequently observed, were detected by the novel real-time phase mapping (ExTRa Mapping). The properties of the LGE areas were assessed using the LGE heterogeneity and the density which was evaluated by the entropy (LGE-entropy) and the volume ratio of the enhancement voxel (LGE-volume ratio), respectively. RESULTS: NPAs were found in 61 (21%) of 287 segments and were mostly found around the pulmonary vein antrum. A receiver operating characteristic curve analysis yielded an optimal cutoff value of 5.7% and 10% for the LGE-entropy and LGE-volume ratio, respectively. The incidence of NPAs was significantly higher at segments with an LGE-entropy of >5.7 and LGE-volume ratio of >10% than at the other segments (38 [30%] of 126 vs. 23 [14%] of 161 segments; p = .001). No NPAs were found at segments with an LGE-volume ratio of >50% regardless of the LGE-entropy. Of five patients with AF recurrence, NPAs outside the PV antrum were not ablated in three patients and the remaining NPAs were ablated, but their LGE-entropy and LGE-volume ratio were low. CONCLUSION: AF rotors are mostly distributed in relatively weak and much more heterogenous LGE areas.

Systemic Delivery of hGhrelin Derivative by Lyophilizate for Dry Powder Inhalation System in Monkeys.

Ghrelin is the peptide that increases the hunger sensation and food intake and is expected to be clinically applied for treatment of diseases such as cachexia and anorexia nervosa. In the clinical application of ghrelin, injections are problematic in that they are invasive and inconvenient. Thus, we aimed to develop a formulation that can eliminate the need for injections and can be applied clinically. We prepared formulations of an hGhrelin derivative, in which the octanoyl group essential for expression of activity is modified to avoid rapid des-acylation, using lyophilizate for a dry powder inhalation (LDPI) system. The formulation of hGhrelin derivative was optimized by the addition of phenylalanine, of which the fine particle fraction of 5 µm or less was 41.7 ± 3.8%. We also performed pharmacokinetic/pharmacodynamic tests in monkeys using the optimum formulation that can be applied clinically. The absolute bioavailability of inhaled hGhrelin derivative with respect to that intravenously injected was 16.9 ± 2.6%. An increase in growth hormone was shown as an effect of the inhaled hGhrelin derivative similar to intravenous injection. The LDPI formulation can deliver the hGhrelin derivative systemically, and it is expected to be applied clinically as a substitute for injections.

Simple Method to Measure the Aerodynamic Size Distribution of Porous Particles Generated on Lyophilizate for Dry Powder Inhalation.

Recently, statistical techniques such as design of experiments are being applied for efficient optimization of oral formulations. To use these statistical techniques for inhalation formulations, efficient methods for rapid determination of the aerodynamic particle size distribution of many samples are needed. Therefore, we aimed to develop a simple method to measure aerodynamic particle size distribution that closely agrees with the results of inhalation characteristic tests. We added attachments for dispersion to the aerodynamic particle sizer (APS) so that formulations could be dispersed under the same condition as for multi-stage liquid impinger (MSLI) measurement. Then, we examined the correlation between MSLI and APS using lyophilizate for dry powder inhalation formulations that generate porous particles just on inhalation. It is difficult to obtain the accurate aerodynamic particle size distribution of porous particles by APS because the particle density is difficult to estimate accurately. However, there was a significant correlation between MSLI and APS when the particle density settings for APS measurement was calculated by a conversion factor based on the result of MSLI. The APS with dispersion attachments and this conversion factor can measure a number of samples in a short time, thereby enabling more efficient optimization of dry powder inhalers.

Lesion characteristics between cryoballoon ablation and radiofrequency ablation with a contact force-sensing catheter: Late-gadolinium enhancement magnetic resonance imaging assessment.

BACKGROUND: Pulmonary vein isolation (PVI) lesions after cryoballoon ablation (CBA) are characterized as a wider and more continuous than that after conventional radiofrequency catheter ablation (RFCA) without the contact force (CF)-sensing technology. However, the impact on the lesion characteristics of ablation with a CF-sensing catheter has not been well discussed. We sought to assess the lesions using late-gadolinium enhancement magnetic resonance imaging (LGE-MRI) and to compare the differences between the two groups (CB group vs. RF group). METHODS: A total of 30 consecutive patients who underwent PVI were enrolled (CB group, 18; RF group, 12). The RF applications were delivered with a target lesion size index (LSI) of 5. The PVI lesions were assessed by LGE-MRI 3 months after the PVI. The region around the PV was divided into eight segments: roof, anterior-superior, anterior carina, anterior inferior, bottom, posterior inferior, posterior carina, and posterior superior segment. The lesion width and visual gap of each segment were compared between the two groups. The visual gaps were defined as no-enhancement site of >4 mm. RESULTS: The mean LSI was 4.7 ± 0.7. The lesion width was significantly wider but the visual gaps were more frequently documented at the bottom segment of right PV in the CBA group (lesion width: 8.1 ± 2.2 vs. 6.3 ± 2.2 mm; p = .032; visual gap at the bottom segment or right PV: 39% vs. 0%; p = .016). CONCLUSIONS: The PVI lesion was wider after CBA, while the visual gaps were fewer after RFCA with a CF-sensing catheter.

Circulating intermediate monocytes and toll-like receptor 4 correlate with low-voltage zones in atrial fibrillation.

Inflammation has been suggested to play a key role in the pathogenesis of atrial fibrillation (AF). Our hypothesis was that this inflammation, mediated by intermediate monocytes and toll-like receptor 4 (TLR4), causes the formation and expansion of low-voltage zones (LVZs). Prior to ablation, the monocyte subsets of 78 AF patients and TLR4 expression of 66 AF patients were analyzed via a flow cytometric analysis. Based on the CD14/CD16 expression, the monocytes were divided into three subsets: classical, intermediate, and non-classical. At the beginning of the ablation session, voltage mapping was performed. LVZs were defined as all bipolar electrogram amplitudes of < 0.5 mV. Correlations between the flow cytometric analysis results and presence of LVZs, as well as the total area of the LVZ, were examined. Patients with LVZs clearly had a higher proportion of intermediate monocytes (10.0 ± 3.6% vs. 7.2 ± 2.7%, p < 0.001) than those without LVZs. TLR4 was much more frequently expressed in the intermediate monocytes than other two monocyte subsets (p < 0.001). Moreover, the TLR4 expression level in intermediate monocytes correlated positively with the total area of the LVZs (r = 0.267, p = 0.030), especially in patients with paroxysmal AF (r = 0.365, p = 0.015). The intermediate monocytes and TLR4 expression positively correlated with LVZs in AF patients.

The effects of 1α,25-dihydroxyvitamin D3 on alveolar repair and bone mass in adiponectin-deficient mice.

Chronic obstructive pulmonary disease (COPD) is a major cause of death worldwide. However, no drugs can regenerate lung tissue in COPD patients, and differentiation-inducing drugs that can effectively treat damaged alveoli are needed. In addition, the presence of systemic comorbidities is also considered problematic. Our previous study revealed that a retinoic acid derivative improved emphysema in elastase-induced COPD model mice at a dose of 1.0 mg/kg, whereas 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) showed an emphysema-improving effect in the same model at 0.1 µg/kg. Elastase-induced COPD model mice do not exhibit a systemic disease state, so evaluation in a model that better reflects the human disease state is considered necessary. To solve this problem, we focused on the adiponectin-deficient mouse and examined the effects of 1,25(OH)2D3 on alveolar regeneration. Fifty-week-old adiponectin-deficient mice were treated with 1,25(OH)2D3 (0.1 µg/kg) twice a week, for 30 weeks. The effects of pulmonary administration on alveolar repair were evaluated according to the distance between alveolar walls (Lm values) and computed tomography (CT) parameters. Bone density was evaluated based on CT. The administration of 1,25(OH)2D3 was confirmed to show a significant therapeutic effect. The Lm values in the control and 1,25(OH)2D3-treated groups were 98 ± 4 µm and 63 ± 1 µm, respectively. However, on CT, the average CT value and % of low attenuation area showed no significant change. In adiponectin-deficient mice, the reduction of bone density (cortical, spongy, and total bone), which is a systemic symptom of COPD, was significantly suppressed by 1,25(OH)2D3 at 80 weeks of age. The present study suggests that 1,25(OH)2D3 could be a potential candidate drug that may provide a radical cure for the lung disease and comorbidities of COPD patients. This work can lead to the development drugs that may provide a radical cure for COPD.