Intracerebroventricular 2-hydroxypropyl-γ-cyclodextrin alleviates hepatic manifestations without distributing to the liver in a murine model of Niemann-Pick disease type C.

Niemann-Pick disease type C (NPC) is a lysosomal lipid storage disorder characterized by progressive neurodegeneration and hepatic dysfunction. A cyclic heptasaccharide, 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD), is currently under clinical investigation for NPC, but its adverse events remain problematic. We previously identified that a cyclic octasaccharide, 2-hydroxypropyl-γ-cyclodextrin (HP-γ-CD), also ameliorated NPC manifestations with higher biocompatibility than HP-ß-CD. However, preclinical studies describing the associations between the biodistribution and pharmacodynamics of these compounds, which are essential for clinical application, are still lacking. Here, we investigated these properties of HP-γ-CD by measuring its organ biodistribution and therapeutic effect after systemic and central administration. The effect of HP-γ-CD on disturbed cholesterol homeostasis appeared within several hours after exposure and persisted for several days in NPC model cells and mice. Tissue distribution indicated that only a small fraction of subcutaneously administered HP-γ-CD rapidly distributed to peripheral organs and contributed to disease amelioration. We found that a subcutaneous dose of HP-γ-CD negligibly ameliorated neurological characteristics because it has limited penetration of the blood-brain barrier; however, an intracerebroventricular microdose unexpectedly attenuated hepatic dysfunction without the detection of HP-γ-CD in the liver. These results demonstrate that central administration of HP-γ-CD can indirectly attenuate peripheral manifestations of NPC.

Nurr1 overexpression in the primary motor cortex alleviates motor dysfunction induced by intracerebral hemorrhage in the striatum in mice.

Hemorrhage-induced injury of the corticospinal tract (CST) in the internal capsule (IC) causes severe neurological dysfunction in both human patients and rodent models of intracerebral hemorrhage (ICH). A nuclear receptor Nurr1 (NR4A2) is known to exert anti-inflammatory and neuroprotective effects in several neurological disorders. Previously we showed that Nurr1 ligands prevented CST injury and alleviated neurological deficits after ICH in mice. To prove direct effect of Nurr1 on CST integrity, we examined the effect of Nurr1 overexpression in neurons of the primary motor cortex on pathological consequences of ICH in mice. ICH was induced by intrastriatal injection of collagenase type VII, where hematoma invaded into IC. Neuron-specific overexpression of Nurr1 was induced by microinjection of synapsin I promoter-driven adeno-associated virus (AAV) vector into the primary motor cortex. Nurr1 overexpression significantly alleviated motor dysfunction but showed only modest effect on sensorimotor dysfunction after ICH. Nurr1 overexpression also preserved axonal structures in IC, while having no effect on hematoma-associated inflammatory events, oxidative stress, and neuronal death in the striatum after ICH. Immunostaining revealed that Nurr1 overexpression increased the expression of Ret tyrosine kinase and phosphorylation of Akt and ERK1/2 in neurons in the motor cortex. Moreover, administration of Nurr1 ligands 1,1-bis(3'-indolyl)-1-(p-chlorophenyl)methane or amodiaquine increased phosphorylation levels of Akt and ERK1/2 as well as expression of glial cell line-derived neurotrophic factor and Ret genes in the cerebral cortex. These results suggest that the therapeutic effect of Nurr1 on striatal ICH is attributable to the preservation of CST by acting on cortical neurons.

Assembly Structure Formation in Bulk and Ultrathin Films of Poly(substituted methylene) Having an Azobenzene Side Chain.

The density of the side chain introduced to a polymer main chain greatly influences the properties and functions of the polymer. This work first reports on the packing structure and properties at an interface of a poly(substituted methylene) where an azobenzene side chain is introduced at every carbon atom in the main chain (C1PAz). The structure and properties are compared with those of a conventional vinyl polymer [poly(methacrylate)] possessing an identical side-chain structure (C2PAz). The packing structure in the bulk state analyzed by X-ray measurements revealed that C1PAz adopts a highly ordered rectangular unit cell structure, whereas C2PAz shows a less ordered lamellar one. Langmuir film balance experiments indicated that both polymers with the trans-azobenzene give essentially the identical 2D side-chain occupying area on water, which agrees well with the smectic B (hexatic packing) model based on the X-ray data. Upon transfer onto a solid substrate, only C1PAz shows a conformational transformation to a spread bilayer-type layer, most probably due to conformational frustration stemming from the crowding of the side chains. This study proposes new insights into the effects of side-chain density on the self-assembly and photoreaction of azobenzene-containing polymers, which are expected to expand the possibilities of polymer design for various applications.

Menaquinone-4 Alleviates Neurological Deficits Associated with Intracerebral Hemorrhage by Preserving Corticospinal Tract in Mice.

Menaquinone-4 (MK-4) is an isoform of vitamin K2 that has been shown to exert various biological actions besides its functions in blood coagulation and bone metabolism. Here we examined the effect of MK-4 on a mouse model of intracerebral hemorrhage (ICH). Daily oral administration of 200 mg/kg MK-4 starting from 3 h after induction of ICH by intrastriatal collagenase injection significantly ameliorated neurological deficits. Unexpectedly, MK-4 produced no significant effects on various histopathological parameters, including the decrease of remaining neurons and the increase of infiltrating neutrophils within the hematoma, the increased accumulation of activated microglia/macrophages and astrocytes around the hematoma, as well as the injury volume and brain swelling by hematoma formation. In addition, ICH-induced increases in nitrosative/oxidative stress reflected by changes in the immunoreactivities against nitrotyrosine and heme oxygenase-1 as well as the contents of malondialdehyde and glutathione were not significantly affected by MK-4. In contrast, MK-4 alleviated axon tract injury in the internal capsule as revealed by neurofilament-H immunofluorescence. Enhanced preservation of the corticospinal tract by MK-4 was also confirmed by retrograde labeling of neurons in the primary motor cortex innervating the spinal cord. These results suggest that MK-4 produces therapeutic effect on ICH by protecting structural integrity of the corticospinal tract.

A tumor endothelial cell-specific microRNA replacement therapy for hepatocellular carcinoma.

Current approved anti-angiogenic drugs (AAD) for hepatocellular carcinoma (HCC) inhibit tumor angiogenesis, but affect the hepatic vasculature resulting in adverse effects. Tumor endothelial cells (TECs) differ from normal endothelial cells. In this study, we aimed to detect TEC-specific miRNAs and develop an anti-angiogenic treatment specific for TECs. We established HCC orthotopic mouse models. TEC-specific miRNAs were detected using a microRNA array. Finally, we evaluated the therapeutic effects of the TEC-specific miRNA agonist cocktail. In total, 260 TEC-specific genes were detected. Among the top ten downregulated TEC-specific miRNAs, miR-139-3p and 214-3p were important for the TEC phenotype. The TEC-specific microRNA agonist cocktail showed significant anti-tumor effects by inhibiting tumor angiogenesis without affecting hepatic vasculatures in HCC orthotopic mouse models. Moreover, it significantly downregulated tip-cell sprouting-related genes. We identified two downregulated TEC-specific miRNAs; microRNA replacement therapy, which targets the downregulated TEC-specific miRNAs, is an effective and promising treatment for HCC.

Synthesis of thermo-responsive polymer gels composed of star-shaped block copolymers by copper-catalyzed living radical polymerization and click reaction.

In recent times, there has been a significant surge in research interest surrounding thermo-responsive water-soluble polyacrylamides, primarily due to their intriguing capability to undergo significant solubility changes in water. These polymers exhibit the remarkable ability to shift from a soluble to an insoluble state in response to temperature variations. The capacity of these polymers to dynamically respond to temperature changes opens up exciting avenues for designing smart materials with tunable properties, amplifying their utility across a spectrum of scientific and technological applications. Researchers have been particularly captivated by the potential applications of thermo-responsive water-soluble polyacrylamides in diverse fields such as drug delivery, gene carriers, tissue engineering, sensors, catalysis, and chromatography separation. This study reports the construction and functionalization of polymer gels consisting of a polymer network of polyacrylamide derivatives with nano-sized structural units. Specifically, thermo-responsive polymer gels were synthesized by combining well-defined star-shaped polymers composed of polyacrylamide derivatives with a multifunctional initiator and linking method through a self-accelerating click reaction. The polymerization system employed a highly living approach, resulting in polymer chains characterized by narrow molecular weight distributions. The method's high functionality facilitated the synthesis of a temperature-responsive block copolymer gel composed of N-isopropyl acrylamide (NIPA) and N-ethyl acrylamide (NEAA). The resulting polymer gel, comprising star-shaped block copolymers of NIPA and NEAA, showcases smooth volume changes with temperature jumps.

This approach's versatility was showcased by creating networks using widely-used vinyl polymers. It can generate various functional and nearly ideal gels and elastomers, allowing for investigating fundamental aspects of polymer networks.

Goreisan regulates cerebral blood flow according to barometric pressure fluctuations in female C57BL/6J mice.

Goreisan is a Kampo medicine used to treat headaches associated with climate change. Here, by using an implantable complementary metal-oxide-semiconductor (CMOS) device, we evaluated the effects of Goreisan and loxoprofen on cerebral blood flow (CBF) dynamics associated with barometric pressure fluctuations in freely moving mice. In the vehicle group, decreasing barometric pressure increased CBF that was prevented by Goreisan and loxoprofen. Notably, Goreisan, but not loxoprofen, reduced CBF after returning to atmospheric pressure. These results indicate that, unlike the mechanism of action of antipyretic analgesics, Goreisan normalizes CBF abnormalities associated with barometric pressure fluctuations by actively reducing CBF increase.

Mirabegron displays anticancer effects by globally browning adipose tissues.

Metabolic reprogramming in malignant cells is a hallmark of cancer that relies on augmented glycolytic metabolism to support their growth, invasion, and metastasis. However, the impact of global adipose metabolism on tumor growth and the drug development by targeting adipose metabolism remain largely unexplored. Here we show that a therapeutic paradigm of drugs is effective for treating various cancer types by browning adipose tissues. Mirabegron, a clinically available drug for overactive bladders, displays potent anticancer effects in various animal cancer models, including untreatable cancers such as pancreatic ductal adenocarcinoma and hepatocellular carcinoma, via the browning of adipose tissues. Genetic deletion of the uncoupling protein 1, a key thermogenic protein in adipose tissues, ablates the anticancer effect. Similarly, the removal of brown adipose tissue, which is responsible for non-shivering thermogenesis, attenuates the anticancer activity of mirabegron. These findings demonstrate that mirabegron represents a paradigm of anticancer drugs with a distinct mechanism for the effective treatment of multiple cancers.

Therapeutic effect of allicin in a mouse model of intracerebral hemorrhage.

Natural compounds with sulfur moiety produce various biological actions that may be beneficial for the therapies of several devastative disorders of the central nervous system. Here we investigated potential therapeutic effect of allicin, an organosulfur compound derived from garlic, in a mouse model of intracerebral hemorrhage (ICH) based on intrastriatal collagenase injection. Daily intraperitoneal administration of allicin (50 mg/kg) from 3 h after induction of ICH afforded neuroprotective effects, as evidenced by the increase of surviving neurons in the hematoma, reduction of axonal transport impairment, and prevention of axon tract injury. In addition, allicin inhibited accumulation of activated microglia/macrophages around the hematoma and infiltration of neutrophils within the hematoma. Allicin also suppressed ICH-induced mRNA upregulation of pro-inflammatory factors such as interleukin 6 and C-X-C motif ligand 2 in the brain, suggesting its anti-inflammatory effect. Moreover, ICH-induced increase of malondialdehyde as well as decrease of total glutathione in the brain was attenuated by allicin. Finally, allicin-treated mice showed better recovery of sensorimotor functions after ICH than vehicle-treated mice. These results indicate that allicin produces a therapeutic effect on ICH pathology via alleviation of neuronal damage, inflammatory responses and oxidative stress in the brain.

Optically Transparent and Color-Stable Elastomer with Structural Coloration under Elongation.

Optically transparent and colored elastomers with high toughness are expected to play an important role in the construction of advanced medical materials, wearable displays, and soft robots. In this study, we found that composite elastomers consisting of amorphous SiO2 particles homogeneously dispersed in high concentrations within a biocompatible acrylic polymer network exhibit optical transparency and bright structural colors. In the composite elastomers, the system in which the SiO2 particles form a colloidal amorphous array hardly changes its structural color hue despite deformation due to elongation. Furthermore, the composite elastomer of the SiO2 particles with the acrylic polymer network also results in high mechanical toughness. In summary, we have shown that the elastomer that exhibits fade-resistant structural coloration formed from safe materials can combine stable coloration and mechanical strength independent of their shape. This is expected to have new potential in future technologies to support our daily life.

Different solubilizing ability of cyclodextrin derivatives for cholesterol in Niemann-Pick disease type C treatment.

BACKGROUND: Niemann-Pick disease type C (NPC) is a fatal neurodegenerative disorder caused by abnormal intracellular cholesterol trafficking. Cyclodextrins (CDs), the most promising therapeutic candidates for NPC, but with concerns about ototoxicity, are cyclic oligosaccharides with dual functions of unesterified cholesterol (UC) shuttle and sink that catalytically enhance the bidirectional flux and net efflux of UC, respectively, between the cell membrane and the extracellular acceptors. However, the properties of CDs that regulate these functions and how they could be used to improve treatments for NPC are unclear. METHODS: We estimated CD-UC complexation for nine CD derivatives derived from native α-, ß-, and γ-CD with different cavity sizes, using solubility and molecular docking analyses. The stoichiometry and complexation ability of the resulting complexes were investigated in relation to the therapeutic effectiveness and toxicity of each CD derivative in NPC experimental models. FINDINGS: We found that shuttle and sink activities of CDs are dependent on cavity size-dependent stoichiometry and substituent-associated stability of CD-UC complexation. The ability of CD derivatives to form 1:1 and 2:1 complexes with UC were correlated with their ability to normalize intracellular cholesterol trafficking serving as shuttle and with their cytotoxicity associated with cellular UC efflux acting as sink, respectively, in NPC model cells. Notably, the ability of CD derivatives to form an inclusion complex with UC was responsible for not only efficacy but ototoxicity, while a representative derivative without this ability negligibly affected auditory function, underscoring its preventability. CONCLUSIONS: Our findings highlight the importance of strategies for optimizing the molecular structure of CDs to overcome this functional dilemma in the treatment of NPC.

KRAS mutation-driven angiopoietin 2 bestows anti-VEGF resistance in epithelial carcinomas.

Defining reliable surrogate markers and overcoming drug resistance are the most challenging issues for improving therapeutic outcomes of antiangiogenic drugs (AADs) in cancer patients. At the time of this writing, no biomarkers are clinically available to predict AAD therapeutic benefits and drug resistance. Here, we uncovered a unique mechanism of AAD resistance in epithelial carcinomas with KRAS mutations that targeted angiopoietin 2 (ANG2) to circumvent antivascular endothelial growth factor (anti-VEGF) responses. Mechanistically, KRAS mutations up-regulated the FOXC2 transcription factor that directly elevated ANG2 expression at the transcriptional level. ANG2 bestowed anti-VEGF resistance as an alternative pathway to augment VEGF-independent tumor angiogenesis. Most colorectal and pancreatic cancers with KRAS mutations were intrinsically resistant to monotherapies of anti-VEGF or anti-ANG2 drugs. However, combination therapy with anti-VEGF and anti-ANG2 drugs produced synergistic and potent anticancer effects in KRAS-mutated cancers. Together, these data demonstrate that KRAS mutations in tumors serve as a predictive marker for anti-VEGF resistance and are susceptible to combination therapy with anti-VEGF and anti-ANG2 drugs.

Acyclic retinoid peretinoin reduces hemorrhage-associated brain injury in vitro and in vivo.

Peretinoin is an acyclic retinoid that stimulates retinoic acid receptors (NR1Bs) and produces therapeutic effects on hepatocellular cancer. We have previously shown that NR1B agonists such as Am80 and all trans-retinoic acid suppress pathogenic events in intracerebral hemorrhage. The present study addressed the actions of peretinoin and Am80 against cytotoxicity of a blood protease thrombin on cortico-striatal slice cultures obtained from neonatal rat brains. Application of 100 U/ml thrombin to the slice cultures for 72 h caused cell death in the cortical region and tissue shrinkage in the striatal region. Peretinoin (50 µM) and Am80 (1 µM) counteracted these cytotoxic effects of thrombin, and the effect of peretinoin and Am80 was blocked by LE540, an NR1B antagonist. A broad-spectrum kinase inhibitor K252a (3 µM) attenuated the cytoprotective effect of peretinoin in the cortical region, whereas a specific protein kinase A inhibitor KT5720 (1 µM) attenuated the protective effect of peretinoin in the cortical and the striatal regions. On the other hand, nuclear factor-κB (NF-κB) inhibitors such as pyrrolidine dithiocarbamate (50 µM) and Bay11-7082 (10 µM) prevented thrombin-induced shrinkage of the striatal region. Peretinoin and Am80 as well as Bay11-7082 blocked thrombin-induced nuclear translocation of NF-κB in striatal microglia and loss of striatal neurons. We also found that daily administration of peretinoin reduced histopathological injury and alleviated motor deficits in a mouse model of intracerebral hemorrhage. These results indicate that NR1B agonists including peretinoin may serve as a therapeutic option for hemorrhagic brain injury.

Wild-type and pathogenic forms of ubiquilin 2 differentially modulate components of the autophagy-lysosome pathways.

Missense mutations of ubiquilin 2 (UBQLN2) have been identified to cause X-linked amyotrophic lateral sclerosis (ALS). Proteasome-mediated protein degradation is reported to be impaired by ALS-associated mutations of UBQLN2. However, it remains unknown how these mutations affect autophagy-lysosome protein degradation, which consists of macroautophagy (MA), microautophagy (mA), and chaperone-mediated autophagy (CMA). Using a CMA/mA fluorescence reporter we found that overexpression of wild-type UBQLN2 impairs CMA. Conversely, knockdown of endogenous UBQLN2 increases CMA activity, suggesting that normally UBQLN2 negatively regulates CMA. ALS-associated mutant forms of UBQLN2 exacerbate this impairment of CMA. Using cells stably transfected with wild-type or ALS-associated mutant UBQLN2, we further determined that wild-type UBQLN2 increased the ratio of LAMP2A (a CMA-related protein) to LAMP1 (a lysosomal protein). This could represent a compensatory reaction to the impairment of CMA by wild-type UBQLN2. However, ALS-associated mutant UBQLN2 failed to show this compensation, exacerbating the impairment of CMA by mutant UBQLN2. We further demonstrated that ALS-associated mutant forms of UBQLN2 also impair MA, but wild-type UBQLN2 does not. These results support the view that ALS-associated mutant forms of UBQLN2 impair both CMA and MA which may contribute to the neurodegeneration observed in patients with UBQLN2-mediated ALS.

Perivascular localized cells commit erythropoiesis in PDGF-B-expressing solid tumors.

BACKGROUND: Tumors possess incessant growth features, and expansion of their masses demands sufficient oxygen supply by red blood cells (RBCs). In adult mammals, the bone marrow (BM) is the main organ regulating hematopoiesis with dedicated manners. Other than BM, extramedullary hematopoiesis is discovered in various pathophysiological settings. However, whether tumors can contribute to hematopoiesis is completely unknown. Accumulating evidence shows that, in the tumor microenvironment (TME), perivascular localized cells retain progenitor cell properties and can differentiate into other cells. Here, we sought to better understand whether and how perivascular localized pericytes in tumors manipulate hematopoiesis. METHODS: To test if vascular cells can differentiate into RBCs, genome-wide expression profiling was performed using mouse-derived pericytes. Genetic tracing of perivascular localized cells employing NG2-CreERT2:R26R-tdTomato mouse strain was used to validate the findings in vivo. Fluorescence-activated cell sorting (FACS), single-cell sequencing, and colony formation assays were applied for biological studies. The production of erythroid differentiation-specific cytokine, erythropoietin (EPO), in TME was checked using quantitative polymerase chain reaction (qPCR), enzyme-linked immunosorbent assay (ELISA, magnetic-activated cell sorting and immunohistochemistry. To investigate BM function in tumor erythropoiesis, BM transplantation mouse models were employed. RESULTS: Genome-wide expression profiling showed that in response to platelet-derived growth factor subunit B (PDGF-B), neural/glial antigen 2 (NG2)+ perivascular localized cells exhibited hematopoietic stem and progenitor-like features and underwent differentiation towards the erythroid lineage. PDGF-B simultaneously targeted cancer-associated fibroblasts to produce high levels of EPO, a crucial hormone that necessitates erythropoiesis. FACS analysis using genetic tracing of NG2+ cells in tumors defined the perivascular localized cell-derived subpopulation of hematopoietic cells. Single-cell sequencing and colony formation assays validated the fact that, upon PDGF-B stimulation, NG2+ cells isolated from tumors acted as erythroblast progenitor cells, which were distinctive from the canonical BM hematopoietic stem cells. CONCLUSIONS: Our data provide a new concept of hematopoiesis within tumor tissues and novel mechanistic insights into perivascular localized cell-derived erythroid cells within TME. Targeting tumor hematopoiesis is a novel therapeutic concept for treating various cancers that may have profound impacts on cancer therapy.

Tumor-derived insulin-like growth factor-binding protein-1 contributes to resistance of hepatocellular carcinoma to tyrosine kinase inhibitors.

BACKGROUND: Antiangiogenic tyrosine kinase inhibitors (TKIs) provide one of the few therapeutic options for effective treatment of hepatocellular carcinoma (HCC). However, patients with HCC often develop resistance toward antiangiogenic TKIs, and the underlying mechanisms are not understood. The aim of this study was to determine the mechanisms underlying antiangiogenic TKI resistance in HCC. METHODS: We used an unbiased proteomic approach to define proteins that were responsible for the resistance to antiangiogenic TKIs in HCC patients. We evaluated the prognosis, therapeutic response, and serum insulin-like growth factor-binding protein-1 (IGFBP-1) levels of 31 lenvatinib-treated HCC patients. Based on the array of results, a retrospective clinical study and preclinical experiments using mouse and human hepatoma cells were conducted. Additionally, in vivo genetic and pharmacological gain- and loss-of-function experiments were performed. RESULTS: In the patient cohort, IGFBP-1 was identified as the signaling molecule with the highest expression that was inversely associated with overall survival. Mechanistically, antiangiogenic TKI treatment markedly elevated tumor IGFBP-1 levels via the hypoxia-hypoxia inducible factor signaling. IGFBP-1 stimulated angiogenesis through activation of the integrin α5ß1-focal adhesion kinase pathway. Consequently, loss of IGFBP-1 and integrin α5ß1 by genetic and pharmacological approaches re-sensitized HCC to lenvatinib treatment. CONCLUSIONS: Together, our data shed light on mechanisms underlying acquired resistance of HCC to antiangiogenic TKIs. Antiangiogenic TKIs induced an increase of tumor IGFBP-1, which promoted angiogenesis through activating the IGFBP-1-integrin α5ß1 pathway. These data bolster the application of a new therapeutic concept by combining antiangiogenic TKIs with IGFBP-1 inhibitors.

Matcha Tea Powder's Antidepressant-like Effect through the Activation of the Dopaminergic System in Mice Is Dependent on Social Isolation Stress.

Matcha tea powder is believed to have various physiological benefits; however, its detailed mechanism of action has been poorly understood. Here, we investigated whether the mental state of mice, due to social isolation stress, affects the antidepressant-like effect of Matcha tea powder by using the tail suspension test. Oral administration of Matcha tea powder reduced the duration of immobility in the stress-susceptible C57BL/6J strain, but not in BALB/c strain. In C57BL/6J mice, SCH23390, a dopamine D1 receptor blocker, prevented Matcha tea powder from exerting its antidepressant-like effect. Matcha tea powder also increased the number of c-Fos-positive cells in the prefrontal cortex (PFC) region and the nucleus accumbens (NAc) region in C57BL/6J mice, but not in BALB/c mice. In contrast, Matcha tea powder did not change the number of c-Fos-positive cells in the ventral tegmental area (VTA) region. Notably, C57BL/6J mice with a shorter immobility time had a higher number of c-Fos-positive cells in the PFC, NAc, and VTA regions. However, no such correlation was observed in the stress-tolerant BALB/c mice. These results suggest that Matcha tea powder exerts an antidepressant-like effect through the activation of the dopaminergic system including the PFC-NAc-VTA circuit and that mental states are important factors affecting the physiological benefits of Matcha tea powder.

New designs for HIV-1 integrase inhibitors: a patent review (2018-present).

INTRODUCTION: Combination antiretroviral therapy (cART) has dramatically reduced morbidity and mortality of HIV-1-infected patients. Integrase strand transfer inhibitors (INSTIs) play an important role as a key drug in cART. The second-generation INSTIs are very potent, but due to the emergence of highly resistant viruses and the demand for more conveniently usable drugs, the development of 'third-generation' INSTIs and mechanistically different inhibitors is actively being pursued. AREAS COVERED: This article reviews the patents (from 2018 to the present) for two classes of HIV-1 integrase inhibitors of INSTIs and integrase-LEDGF/p75 allosteric inhibitors (INLAIs). EXPERT OPINION: Since the approval of the second-generation INSTI dolutegravir, the design of new INSTIs has been mostly focused on its scaffold, carbamoylpyridone (CAP). This CAP scaffold is used not only for HIV-1 INSTIs but also for drug discoveries targeting other viral enzymes. With the approval of cabotegravir as a regimen of long-acting injection in combination with rilpivirine, there is a growing need for longer-acting agents. INLAIs have been intensely studied by many groups but have yet to reach the market. However, INLAIs have recently been reported to also function as a latency promoting agent (LPA), indicating further development possibilities.

Induction of Highly Ordered Liquid Crystalline Phase of an Azobenzene Side Chain Polymer by Contact with 4'-Pentyl-4-cyanobiphenyl: An In Situ Study.

The orientation of liquid crystal (LC) molecules is significantly governed by solid interfaces and free surfaces, and a variety of functional materials have been developed using these properties. Although LC materials are already in industrial use, particularly for LC display panels, various studies have been conducted in recent years to better grasp the interface behavior of LC molecules. In this work, we succeeded in in situ observations of induction of higher ordered LC phases at the interface between a side-chain LC azobenzene polymer film with a thickness of ∼400 nm and a low-molecular-mass nematic LC, 4'-pentyl-4-cyanobiphenyl of 35 µm thickness, using small-angle X-ray scattering measurements and polarized optical microscopy. It is revealed that the two different mesogens cooperatively form hybrid higher ordered smectic LC phases probably through weak electron transfer immediately after interfacial contact. The induction process consists of three stages in terms of dynamic structure evolutions. Upon UV irradiation, the hybrid smectic LC structure diminished. This study provides new insights into the behavior of LC molecules near the alignment film on the solid substrate.

Induced Smectic E Phase in a Binary Blend of Side-Chain Liquid Crystalline Polymers.

Two liquid crystalline polymers containing an azobenzene or cyanobiphenyl mesogenic side chain that adopt smectic A phases are mechanically mixed at 1:1 mesogen molar ratio at an isotropic phase temperature and then cooled. The resultant binary polymer mixture behaves like a single component as revealed by polarized microscopy observation and differential scanning calorimetry, indicating that the binary mixture forms a fully compatible polymer blend. Moreover, the simple polymer blend unexpectedly leads to a higher-ordered smectic E phase where a herringbone structure is formed with restricted mesogen axis rotation. These results suggest a specific intermolecular interaction between the two mesogens, thereby inducing unusual compatibilized polymer blends and the most ordered liquid crystal (LC) phase.