Neprilysin Inhibition Promotes Skeletal Growth via the CNP/NPR-B Pathway.

C-type natriuretic peptide (CNP) plays a crucial role in enhancing endochondral bone growth and holds promise as a therapeutic agent for impaired skeletal growth. To overcome CNP's short half-life, we explored the potential of dampening its clearance system. Neprilysin (NEP) is an endopeptidase responsible for catalyzing the degradation of CNP. Thus, we investigated the effects of NEP inhibition on skeletal growth by administering sacubitril, a NEP inhibitor, to C57BL/6 mice. Remarkably, we observed a dose-dependent skeletal overgrowth phenotype in mice treated with sacubitril. Histological analysis of the growth plate revealed a thickening of the hypertrophic and proliferative zones, mirroring the changes induced by CNP administration. The promotion of skeletal growth observed in wild-type mice treated with sacubitril was nullified by the knockout of cartilage-specific natriuretic peptide receptor B (NPR-B). Notably, sacubitril promoted skeletal growth in mice only at 3 to 4 weeks of age, a period when endogenous CNP and NEP expression was higher in the lumbar vertebrae. Additionally, sacubitril facilitated endochondral bone growth in organ culture experiments using tibial explants from fetal mice. These findings suggest that NEP inhibition significantly promotes skeletal growth via the CNP/NPR-B pathway, warranting further investigations for potential applications in people with short stature.

Separation of enantiomers of chiral fullerene derivatives through enantioselective encapsulation within an adaptable helical cavity of syndiotactic poly(methyl methacrylate) with helicity memory.

Optically active left (M)- and right (P)-handed helical syndiotactic poly(methyl methacrylate)s (M- and P-st-PMMAs) with a helicity memory enantioselectively encapsulated the racemic C60 derivatives, such as 3,4-fulleroproline tert-butyl ester (rac-1) and tetraallylated C60 (rac-2), as well as the C60-bound racemic 310-helical peptides (rac-3) within their helical cavities to form peapod-like inclusion complexes and a unique "helix-in-helix" superstructure, respectively. The enantiomeric excess (ee) and separation factor (enantioselectivity) (α) of the analyte 1 (ee = 23%-25% and α = 2.35-2.50) encapsulated within the helical cavities of the M- and P-st-PMMAs were higher than those of the analytes 2 and 3 (ee = 4.3%-6.0% and α = 1.28-1.50). The optically pure (S)- and (R)-1 were found to more efficiently induce an excess one-handed helical conformation in the st-PMMA backbone than the optically pure (S)- and (R)-1-phenylethylamine, resulting in intense mirror-image vibrational circular dichroism (VCD) spectra in the PMMA IR regions. The excess one-handed helices induced in the st-PMMAs complexed with (S)- and (R)-1 were memorized after replacement with the achiral C60, and the complexes exhibited induced electric CDs in the achiral C60 chromophore regions.

Association Between Pancreatic Cysts and Diabetes Mellitus in Von Hippel-Lindau Disease.

INTRODUCTION: Pancreatic cysts are frequently observed in patients with von Hippel-Lindau disease (VHL), and they are considered clinically not important. This study aimed to evaluate the association between pancreatic cysts and diabetes mellitus (DM) in patients with VHL. METHODS: Among patients who were on a patient list at the VHL Center at Kyoto University Hospital as of December 2022, those who had undergone an upper abdominal magnetic resonance imaging study after 2010 were retrospectively evaluated. The presence or absence of DM and high glycated hemoglobin (HbA1c) levels (>6.0%) were assessed. Patients were divided into two groups: those with DM or high HbA1c levels, and those without DM or high HbA1c levels. The area of the whole pancreas, including the pancreatic cysts and tumors, the area of the pancreatic cysts, and the percentage of pancreatic cysts, calculated by dividing the area of pancreatic cysts by the area of the whole pancreas, were measured on T2-weighted magnetic resonance images and compared between the two groups. RESULTS: Thirty-six patients with VHL, comprising 22 men and 14 women, with a mean age of 36.4 years (range, 11-79 years), were identified. Seven patients had DM, and two additional patients had high HbA1c levels. The area of the pancreatic cysts (p = 0.0013) was significantly larger and the percentage of the pancreatic cysts (p = 0.0016) was significantly higher in patients with DM or high HbA1c levels (n = 9) than in patients without DM or high HbA1c levels (n = 27); however, the difference in the area of the whole pancreas was not significant (p = 0.068). CONCLUSION: Our findings suggest that patients with VHL who have a large area covered by pancreatic cysts are more likely to have DM than those without.

Prediction-based prompt levothyroxine replacement to prevent a hypothyroid state after immune-related adverse events involving the thyroid gland.

Immune checkpoint inhibitors (ICIs) are used for various malignancies, although they frequently cause immune-related adverse events involving the thyroid gland (thyroid irAEs). We conducted a retrospective cohort study to elucidate thyroid function outcomes. Fifty of 639 patients who received PD-1 blockade therapy met criteria and were divided into the following groups: thyrotoxicosis with subsequent hypothyroidism (Toxic-Hypo, n = 21); thyrotoxicosis without subsequent hypothyroidism (Toxic, n = 9); and hypothyroidism without prior thyrotoxicosis (Hypo, n = 20). The Toxic-Hypo group developed thyroid irAEs earlier than the Toxic group (26 vs. 91 days; p < 0.001), and had higher serum free T4 levels (3.210 vs. 1.880 ng/dL; p = 0.011). In addition, positive anti-thyroglobulin antibodies (TgAbs) at thyroid irAE onset were more common in the Toxic-Hypo group (93.3%) than in the Toxic group (0.0%; p = 0.005) and Hypo group (44.4%; p = 0.007). The Toxic-Hypo group developed severe hypothyroidism and required larger levothyroxine (LT4) doses than the Hypo group (75 vs. 25 µg/day; p = 0.007). We predicted that patients with positive TgAbs who developed severe thyrotoxicosis within 4 weeks after the first ICI administration would develop subsequent hypothyroidism. We treated 4 such patients with prompt LT4 replacement, characterized by LT4 initiation after thyrotoxicosis improvement and quick dose titration. Their euthyroid state was successfully maintained, in contrast with patients receiving conventional replacement. In conclusion, rapid-onset severe thyrotoxicosis in patients with TgAbs correlated with a high likelihood of subsequent hypothyroidism. Accordingly, prompt LT4 replacement is suggested to prevent a severely hypothyroid state.

Nicotine Reduces Reactive Oxygen Species and Enhances Cell Proliferation via the α4 Nicotinic Acetylcholine Receptor Subunit in Human Induced Pluripotent Stem Cells.

The effects of smoking on fetal development and stem cell differentiation are not fully understood. Although nicotinic acetylcholine receptors (nAChRs) are expressed in many organs of the human body, their significance in human induced pluripotent stem cells (hiPSCs) remains unclear. After expression levels of nAChR subunits in hiPSCs were determined, the effects of the nAChR agonist, nicotine, on undifferentiated hiPSCs were evaluated using a Clariom S Array. We also determined the effect of nicotine alone and with a nAChR subunit antagonist on hiPSCs. nAChR α4, α7, and ß4 subunits were strongly expressed in hiPSCs. cDNA microarray, gene ontology, and enrichment analyses showed that exposing hiPSCs to nicotine altered expression of genes associated with immune responses, neurological system, carcinogenesis, cell differentiation, and cell proliferation. Particularly affected was metallothionein, which acts to decrease reactive oxygen species (ROS). The nicotine-induced reduction of ROS in hiPSCs was canceled by an α4 subunit or nonselective nAChR antagonist. HiPSC proliferation was increased by nicotine, and this effect, too, was canceled by an α4 antagonist. In conclusion, nicotine reduces ROS and enhances cell proliferation through the α4 nAChR subunit in hiPSCs. These findings provide new insight into the significance of nAChRs on human stem cells and fertilized human ova.

Delayed-onset immune-related adverse events involving the thyroid gland by immune checkpoint inhibitors in combination with chemotherapy: a case report and retrospective cohort study.

Immune checkpoint inhibitors (ICIs) frequently cause immune-related adverse events (irAEs) that often involve endocrine organs. Pembrolizumab and atezolizumab are currently administered in combination with chemotherapy for several malignancies. Although transient thyrotoxicosis within 6 weeks after the first ICI dose is the typical course of thyroid irAEs with ICI monotherapy, we encountered a unique course of a thyroid irAE in a patient who received combination therapy consisting of pembrolizumab plus pemetrexed and carboplatin. Delayed onset of thyrotoxicosis occurred at 22 weeks after the first dose of pembrolizumab. To understand more about this curious event, we conducted a retrospective cohort study of the following groups: pembrolizumab monotherapy (Pem-mono), pembrolizumab plus chemotherapy (Pem-combi), atezolizumab monotherapy (Atezo-mono), and atezolizumab plus chemotherapy (Atezo-combi). There were no differences in the incidence of overt thyroid irAEs: Pem-mono, 12 of 151 patients (7.9%) versus Pem-combi, 4 of 56 patients (7.1%) (p = 0.85) and Atezo-mono, 5 of 27 patients (18.5%) versus Atezo-combi, 5 of 57 patients (8.8%) (p = 0.20). Through detailed analyses of patients with thyrotoxicosis, we found some patients with delayed-onset thyroid irAE, defined as development at 16 weeks or more after the first ICI dose. Delayed-onset thyroid irAEs were only observed in the combination therapy groups: Pem-combi or Atezo-combi, 3 of 8 patients versus Pem-mono or Atezo-mono, 0 of 10 patients. Our observation that thyroid irAE development can be delayed with ICIs when used in combination with chemotherapy suggests longer monitoring of thyroid function is needed to avoid missing irAEs.

Sodium-Glucose Cotransporter 2 Inhibitors and New-onset Type 2 Diabetes in Adults With Prediabetes: Systematic Review and Meta-analysis of Randomized Controlled Trials.

CONTEXT: The preventive effect of sodium-glucose cotransporter 2 (SGLT2) inhibitors for new-onset diabetes was investigated in secondary analyses of several randomized controlled trials (RCTs). However, the results were inconsistent. OBJECTIVE: This work aimed to synthesize available evidence and evaluate whether SGLT2 inhibitors are effective in preventing new-onset diabetes. METHODS: In this systematic review and meta-analysis of RCTs, MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched through February 11, 2022. Two independent authors screened the search results and extracted summary data from eligible RCTs (including original and post hoc analyses) comparing SGLT2 inhibitors and placebo for the risk of new-onset diabetes among adults with prediabetes. Meta-analysis was conducted using random-effects models to calculate risk ratios and 95% CIs. RESULTS: We included 4 RCTs with 5655 participants who had prediabetes. Based on the random-effects meta-analysis, SGLT2 inhibitors were significantly associated with a lower risk of new-onset diabetes (relative risk, 0.79; 95% CI, 0.68-0.93). The relative risks of new-onset diabetes in dapagliflozin and empagliflozin were 0.68 (95% CI, 0.52-0.89) and 0.87 (95% CI, 0.72-1.04), respectively (P-for-heterogeneity = .14). The frequency of severe hypoglycemia was not elevated in the SGLT2 inhibitors group compared to the placebo group. CONCLUSION: In this meta-analysis, SGLT2 inhibitors were associated with a reduced risk of new-onset type 2 diabetes among adults with prediabetes and heart failure or chronic kidney disease. These findings indicate the potential usefulness of SGLT2 inhibitors in preventing diabetes among high-risk populations with prediabetes.

High-throughput Screening in Combination With a Cohort Study for Iodothyronine Deiodinases.

Regulatory mechanisms of iodothyronine deiodinases (DIOs) require further elucidation, and conventional methods for evaluating DIOs are unsuitable for high-throughput screening (HTS). Here we explored factors of transcriptional regulation of 3 types of DIOs (DIO1, DIO2, and DIO3) from a chemical library using our designed HTS. We constructed HTS based on a promoter assay and performed a screen of 2480 bioactive compounds. For compounds that were clinically approved, we validated hit compounds through a retrospective cohort study in our department that evaluated changes in thyroid function in patients using the compounds as drug therapy. Furthermore, we verified the involvement of DIOs using mice treated with the compounds. Of the hit compounds, 6 and 7 compounds transcriptionally up- and downregulated DIO1, respectively; 34 transcriptionally upregulated DIO2; and 5 and 2 compounds transcriptionally up- and downregulated DIO3, respectively. The cohort study clarified the clinical effects of some hit compounds: ritodrine increased free triiodothyronine (fT3)/free thyroxine (fT4) ratio and decreased serum thyroid-stimulating hormone (TSH) levels, tadalafil increased serum fT3 levels, and tyrosine kinase inhibitors (TKIs) decreased serum fT3 and fT4 levels and increased serum TSH levels. Following in vivo experiments using treated mice, consistent results were observed in ritodrine, which upregulated DIO2 in the thyroid gland. In conclusion, we completed HTS for DIOs and obtained attractive hit compounds. Our cohort study revealed the clinical significance of ritodrine, sildenafil, and TKIs. We hope our unique method will contribute to analyzing various targets and lists of hit compounds will promote understanding of DIOs.

Thyroid hormone economy in mice overexpressing iodothyronine deiodinases.

In peripheral tissues, triiodothyronine (T3) production and consequent thyroid hormone actions are mainly regulated by iodothyronine deiodinases (DIOs) classified into 3 types: D1, D2, and D3. We aimed to investigate the effects of peripheral DIOs on thyroid hormone economy independent of the hypothalamus-pituitary-thyroid axis. We cloned coding sequences of human DIOs with FLAG-tag and HiBiT-tag sequences into a pcDNA3.1 vector. To obtain full-length proteins, we modified these vectors by cloning the selenocysteine insertion sequence of each DIO (SECIS vectors). Western blot analyses and HiBiT lytic assay using HEK293T cells revealed that SECIS vectors expressed full-length proteins with substantial activity. Subsequently, in vivo transfections of pLIVE-based SECIS vectors into male C57BL/6J mice were performed by hydrodynamic gene delivery to generate mice overexpressing DIOs predominantly in the liver (D1, D2, and D3 mice). After 7 days from transfections, mice were analyzed to clarify phenotypes. To summarize, serum thyroid hormone levels did not change in D1 mice but D2 mice had higher serum free T3 levels. D3 mice developed hypothyroidism with higher serum reverse T3 (rT3) levels. Transfections with levothyroxine administration suggested that thyroid hormone action was upregulated in D2 mice. Our DIO-overexpressing mice provided insights on the physiological properties of upregulated DIOs: D2 augments local thyroid hormone action and recruits T3 into the circulation: D3 decreases circulating T3 and T4 levels with elevated rT3, leading to consumptive hypothyroidism. As D3 mice are expected to be a novel hypothyroidism model, they can contribute to progress in the field of thyroid hormone economy and action.

Opioid-induced adrenal insufficiency in transdermal fentanyl treatment: a revisited diagnosis in clinical setting.

Opioids are widely used for treatment of acute and chronic pain. However, opioids have several well-known clinical adverse effects such as constipation, nausea, respiratory depression and drowsiness. Endocrine dysfunctions are also opioid-induced adverse effects but remain under-diagnosed in clinical settings, especially opioid-induced adrenal insufficiency (OIAI). A 46-year-old woman was treated with transdermal fentanyl at a dose of 90-120 mg daily morphine milligram equivalent for non-malignant chronic pain for four years. Fatigue, loss of appetite and decrease in vitality began about two years after starting fentanyl. Subsequently, constipation and abdominal pain appeared and became worse, which led to suspicion of adrenal insufficiency. Clinical diagnosis of OIAI was established based on laboratory findings of secondary adrenal insufficiency, including corticotropin-releasing hormone stimulation test, clinical history of long-term fentanyl use, and exclusion of other hypothalamic-pituitary diseases. Oral corticosteroid replacement therapy was unable to relieve her abdominal pain and constipation; opioid-rotation and dose-reduction of fentanyl were not feasible because of her persistent pain and severe anxiety. While her clinical course clearly suggested that long-term, relatively high-dose transdermal fentanyl treatment may have contributed to the development of secondary adrenal insufficiency, the symptoms associated with OIAI are generally non-specific and complex. Together with under-recognition of OIAI as a clinical entity, the non-specific, wide range of symptoms can impede prompt diagnosis. Thus, vigilance for early symptoms enabling treatments including corticosteroid replacement therapy is necessary for patients taking long-term and/or high dose opioid treatment.

Water-Mediated Reversible Control of Three-State Double-Stranded Titanium(IV) Helicates.

A stimuli-responsible reversible structural transformation is of key importance in biological systems. We now report a unique water-mediated reversible transformation among three discrete double-stranded dinuclear titanium(IV) achiral meso- and chiral rac-helicates linked by a mono(µ-oxo) or a bis(µ-hydroxo) bridge between the titanium ions through hydration/dehydration or its combination with a water-mediated dynamic cleavage/re-formation of the titanium-phenoxide (Ti-OPh) bonds. The bis(µ-hydroxo) bridged titanium(IV) meso-helicate prepared from two tetraphenol strands with titanium(IV) oxide was readily dehydrated in CD3CN containing a small amount of water upon heating, accompanied by Ti-OPh bond cleavage/re-formation catalyzed by water, resulting in the formation of the mono(µ-oxo)-bridged rac-helicate, which reverted back to the original bis(µ-hydroxo)-bridged meso-helicate upon hydration in aqueous CD3CN. These reversible transformations between the meso- and rac-helicates were also promoted in the presence of a catalytic amount of an acid, which remarkably accelerated the reactions at lower temperature. Interestingly, in anhydrous CD3CN, the bis(µ-hydroxo)-bridged meso-helicate was further slowly converted to a different helicate, while its meso-helicate framework was maintained, namely the mono(µ-oxo)-bridged meso-helicate, through dehydration upon heating and its meso to meso transformation was significantly accelerated in the presence of cryptand[2.2.1], which contributes to removing Na+ ions coordinated to the helicate. Upon cooling, the backward meso to meso transformation took place via hydration. Hence, three different, discrete double-stranded chiral rac- and achiral meso-titanium(IV) helicates linked by a mono(µ-oxo) or a bis(µ-hydroxo) bridge were successfully generated in a controllable manner by a change in the water content of the reaction media.

Clinical features and thyroid dysfunction in adverse events involving the pituitary gland during PD-1 blockade therapy.

OBJECTIVE: Programmed cell death-1 (PD-1) blockade therapy, an immune checkpoint treatment, can induce hypophysitis or hypopituitarism as an immune-related adverse event (pituitary irAE). We aimed to clarify the clinical features of pituitary irAEs during PD-1 blockade therapy. DESIGN, PATIENTS AND MEASUREMENTS: This retrospective study investigated consecutive patients treated with nivolumab, an anti-PD-1 antibody, at Kyoto University Hospital between 1 September 2014 and 31 August 2019. We examined patients' baseline characteristics and analysed the clinical data of those who developed pituitary irAEs. RESULTS: Of the 374 recruited patients, 7 (1.9%) developed pituitary irAEs, and each presented with isolated secondary adrenal insufficiency. In 4 patients, changes in ACTH were delayed relative to those in cortisol: when serum cortisol levels fell below the reference range, plasma ACTH levels were still normal. Pituitary irAEs were accompanied by elevated serum-free T3 (fT3) levels, which resolved with glucocorticoid replacement. Serum TSH levels were not suppressed despite elevated serum fT3 levels and 1 patient even presented with high fT3 level above the reference range (fT3, 7.1 pmol/L; free T4 (fT4), 13.9 pmol/L; and TSH, 5.1 mIU/L). CONCLUSIONS: Isolated secondary adrenal insufficiency was a common pituitary irAE during PD-1 blockade therapy. This condition was accompanied by thyroid dysfunction, including elevation of fT3 without TSH suppression.

Helix-Sense-Selective Encapsulation of Helical Poly(lactic acid)s within a Helical Cavity of Syndiotactic Poly(methyl methacrylate) with Helicity Memory.

We report a highly enantio- and helix-sense-selective encapsulation of helical poly(lactic acid)s (PLAs) through a unique "helix-in-helix" superstructure formation within the helical cavity of syndiotactic poly(methyl methacrylate) (st-PMMA) with a one-handed helicity memory, which enables the separation of the enantiomeric helices of the left (M)- and right (P)-handed-PLAs. The M- and P-helical PLAs with different molar masses and a narrow molar mass distribution were prepared by the ring-opening living polymerization of the optically pure l- and d-lactides, respectively, followed by end-capping of the terminal residues of the PLAs with a 4-halobenzoate and then a C60 unit, giving the C60-free and C60-bound M- and P-PLAs. The C60-free and C60-bound M- and P-PLAs formed crystalline inclusion complexes with achiral st-PMMA accompanied by a preferred-handed helix induction in the st-PMMA backbone, thereby producing helix-in-helix superstructures with the same-handedness to each other. The induced helical st-PMMAs were retained after replacement with the achiral C60, indicating the memory of the induced helicity of the st-PMMAs. Both the C60-free and C60-bound helical PLAs were enantio- and helix-sense selectively encapsulated into the helical hollow space of the optically active M- and P-st-PMMAs with the helicity memory prepared using chiral amines. The M- and P-PLAs are preferentially encapsulated within the M- and P-st-PMMA helical cavity with the same-handedness to each other, respectively, independent of the terminal units. The C60-bound PLAs were more efficiently and enantioselectively trapped in the st-PMMA compared to the C60-free PLAs. The enantioselectivities were highly dependent on the molar mass of the C60-bound and C60-free PLAs and significantly increased as the molar mass of the PLAs increased.

A case of systemic lupus erythematosus complicated by subclinical Cushing's syndrome: case report.

An 18-year-old female was diagnosed with subclinical Cushing's syndrome (CS) due to a left adrenal adenoma. When she was 20 years old, she developed lupus nephritis. She was treated with high-dose prednisolone (PSL) and soon developed the symptoms of CS. When she was 25 years old, we evaluated her serum glucocorticoid level while she continued to take oral PSL. The result suggested her CS was affected by both the oral PSL and the endogenous cortisol secreted by the adrenocortical adenoma, which was therefore resected. Seven months after the operation, the patient's body weight was decreasing, and her SLE remained in clinical remission. CS complicated by SLE is rare, and the decision to surgically remove an adrenal tumor in such a case is even more rare.

Remote-controlled regio- and diastereodifferentiating photodimerization of a dynamic helical peptide-bound 2-substituted anthracene.

Photodimerization of a novel 2-substituted anthracene linked to a right-handed 310-helical nonapeptide induced by long-range chiral information transfer from the remote chiral l-Val residue through a chiral domino effect proceeded in a highly regio- and diastereo-differentiating manner to produce the chiral head-to-head anti-photodimer in 90% relative yield with up to 97% diastereomeric excess.

C-type natriuretic peptide (CNP)/guanylate cyclase B (GC-B) system and endothelin-1(ET-1)/ET receptor A and B system in human vasculature.

To assess the physiological and clinical implications of the C-type natriuretic peptide (CNP)/guanylyl cyclase B (GC-B) system in the human vasculature, we have examined gene expressions of CNP and its receptor, GC-B, in human vascular endothelial cells (ECs) and smooth muscle cells (SMCs) and have also compared the endothelin-1(ET-1)/endothelin receptor-A (ETR-A) and endothelin receptor-B (ETR-B) system in human aortic ECs (HAECs) and vascular SMCs (HSMCs) in vitro. We also examined these gene expressions in human embryonic stem (ES)/induced pluripotent stem cell (iPS)-derived ECs and mural cells (MCs). A little but significant amount of mRNA encoding CNP was detected in both human ES-derived ECs and HAECs. A substantial amount of GC-B was expressed in both ECs (iPS-derived ECs and HAECs) and SMCs (iPS-derived MCs and HSMCs). ET-1 was expressed solely in ECs. ETR-A was expressed in SMCs, while ETR-B was expressed in ECs. These results indicate the existence of a vascular CNP/GC-B system in the human vascular wall, indicating the evidence for clinical implication of the CNP/GC-B system in concert with the ET-1/ETR-A and ETR-B system in the human vasculature.

A Modular Differentiation System Maps Multiple Human Kidney Lineages from Pluripotent Stem Cells.

Recent studies using human pluripotent stem cells (hPSCs) have developed protocols to induce kidney-lineage cells and reconstruct kidney organoids. However, the separate generation of metanephric nephron progenitors (NPs), mesonephric NPs, and ureteric bud (UB) cells, which constitute embryonic kidneys, in in vitro differentiation culture systems has not been fully investigated. Here, we create a culture system in which these mesoderm-like cell types and paraxial and lateral plate mesoderm-like cells are separately generated from hPSCs. We recapitulate nephrogenic niches from separately induced metanephric NP-like and UB-like cells, which are subsequently differentiated into glomeruli, renal tubules, and collecting ducts in vitro and further vascularized in vivo. Our selective differentiation protocols should contribute to understanding the mechanisms underlying human kidney development and disease and also supply cell sources for regenerative therapies.

Human iPS cell-derived mural cells as an in vitro model of hereditary cerebral small vessel disease.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is one of the most common forms of hereditary cerebral small vessel diseases and is caused by mutations in NOTCH3. Our group has previously reported incorporation of NOTCH3 extracellular domain (N3ECD) in the CADASIL-specific granular osmiophilic materials and increase of PDGFRß immunoreactivity in CADASIL postmortem brains. Here, we aimed to establish an in vitro model of CADASIL, which can recapitulate those CADASIL phenotypes, using induced pluripotent stem cells (iPSCs). We have refined a differentiation protocol of endothelial cells to obtain mature mural cells (MCs) with their characteristic properties. iPSCs from three CADASIL patients with p.Arg182Cys, p.Arg141Cys and p.Cys106Arg mutations were differentiated into MCs and their functional and molecular profiles were compared. The differentiated CADASIL MCs recapitulated pathogenic changes reported previously: increased PDGFRß and abnormal structure/distribution of filamentous actin network, as well as N3ECD/LTBP-1/HtrA1-immunopositive deposits. Migration rate of CADASIL MCs was enhanced but suppressed by knockdown of NOTCH3 or PDGFRB. CADASIL MCs showed altered reactivity to PDGF-BB. Patient-derived MCs can recapitulate CADASIL pathology and are therefore useful in understanding the pathogenesis and developing potential treatment strategies.

Enantiodifferentiating Photodimerization of a 2,6-Disubstituted Anthracene Assisted by Supramolecular Double-Helix Formation with Chiral Amines.

A novel 2,6-anthrylene-linked bis(m-terphenylcarboxylic acid) strand (1) self-associates into a racemic double-helix. In the presence of chiral mono- and diamines, either a right- or left-handed double-helix was predominantly induced by chiral amines sandwiched between the carboxylic acid strands with accompanying stacking of the two prochiral anthracene linker units in an enantiotopic face-selective way, as revealed by circular dichroism and NMR spectral analyses. The photoirradiation of the optically active double helices complexed with chiral amines proceeded in a diastereo- (anti or syn) and enantiodifferentiating way to afford the chiral anti-photodimer with up to 98 % enantiomeric excess when (R)-phenylethylamine was used as a chiral double-helix inducer. The resulting optically active anti-photodimer can recognize the chirality of amines and diastereoselectively complex with chiral amines.

Complementary double-stranded helical oligomers bearing achiral bifunctional groups that catalyze asymmetric aldol reaction.

Two novel chiral dimer and trimer strands composed of m-terphenyl groups linked through p-diethynylbenzene units with the chiral amidine group and achiral piperazine group introduced at the terminus or center of the strands, respectively, and its complementary achiral carboxylic acid dimer and trimer were synthesized. The complementary chiral/achiral strands form an excess-handed double-helical structure as supported by intense split-type Cotton effects in the absorption regions of the conjugated backbones biased by the chiral amidinium-carboxylate salt bridges. The double-helical trimer was found to catalyze the direct aldol reaction of cyclohexanone with 4-nitrobenzaldehyde and produce the products with a moderate enantioselectivity despite the fact that the catalytically active bifunctional piperazine/carboxylic acid pair introduced in the middle is achiral, indicating the key role of the one-handed double-helical framework for supramolecular bifunctional organocatalysis.