Biological & pharmaceutical bulletin最新文献

Vitamin D plays a crucial role in immune system function. Several studies have indicated that genetic variations in the vitamin D receptor (VDR) and vitamin D binding protein (VDBP, encoded by GC gene) increase the risk of developing asthma. However, the effect of these variations on the prognosis and clinical outcomes of asthma remains unclear. This study, involving 152 adult patients with asthma, aimed to assess the influence of VDR and GC polymorphisms on asthma severity and its exacerbation. Gene polymorphisms previously associated with asthma risk were analyzed, and VDR mRNA expression levels were evaluated in peripheral blood mononuclear cells. The AA genotype of the VDR rs2228570 polymorphism was associated with an elevated risk of severe asthma compared to the AG/GG genotype (odds ratio, 3.20; 95% confidence interval [CI], 1.24-8.28). Furthermore, patients with the rs2228570 AA genotype showed an elevated risk of exacerbation during the 1-year follow-up period (hazard ratio, 4.01; 95% CI, 1.75-9.15). VDR mRNA expression was significantly reduced in patients with the AA genotype. Furthermore, the mRNA expression levels of GLCCI1, HDAC2, NR3C1, and NFE2L2, which are associated with steroid response, were reduced in patients with the AA genotype. Our findings indicate that patients with the AA genotype of VDR rs2228570 are more likely to experience severe asthma and exacerbations. This polymorphism has the potential to reduce vitamin D efficacy by altering VDR function and expression, potentially resulting in increased inflammation and reduced steroid responsiveness in patients with asthma.

As unexpected adverse events and successful drug repositioning have shown, drug effects are complex and include aspects not recognized by developers. How can we understand these unrecognized drug effects? Drug effects can be numerized by encompassing biological responses to drugs. For instance, the transcriptome data of cultured cells and toxicopathological images of mice treated with a compound represent the effects of the compound in vitro and in vivo, respectively. As a next step, we focused on pattern recognition, a data science framework to extract essentially important low-dimensional latent variables from high-dimensional observed data such as latent variable models. Latent variables are low-dimensional, allowing us to visualize drug effects in an easily recognizable form, such as a radar chart. This bird's-eye view of drug effects enables us to compare them with existing knowledge, potentially articulating the effects of drugs as the known knowns and known unknowns. We believe that the three-step strategy of numerization, visualization, and articulation will allow us to understand drug effects comprehensively, and we are currently verifying this approach. In this review, we will introduce these candidate studies and hope to share our interest in "pattern recognition of biological responses," the pillar of our group.

Cancer is an age-related disease that affects one in two Japanese individuals, placing a significant burden on both patients and caregivers due to its clinical characteristics, high treatment costs, and associated adverse events (AEs). Consequently, cancer treatment remains a major public concern. In recent years, patient-centered medical care has gained increasing attention and is strongly desired in cancer treatment. Companion diagnostics (CDx) are expected to facilitate personalized treatment; however, their current status remains unclear. In this study, we evaluated the role of CDx in anticancer drug treatment based on data available at the time of drug approval. Our analysis revealed that the benefit-risk ratio, defined as the objective response rate of an anticancer drug divided by the incidence of severe AEs, was significantly higher for anticancer drugs requiring CDx (wCDx) in Japanese patients (1.54-fold, p < 0.0135) than for anticancer drugs not requiring CDx. Although the objective response rate did not differ between the 2 groups, the incidence of severe AEs was lower in the wCDx group. These findings suggest that CDx helps identify patients who are better suited for specific anticancer treatments and/or that active pharmaceutical ingredients in wCDx therapies carry a lower risk of severe AEs. To further promote patient-centered medical care, the active development of CDx alongside new anticancer drugs should be encouraged, despite the higher development hurdles, through regulatory support, particularly since drug pricing does not differ between the 2 groups.

The purpose of this study was to explore the potential therapeutic effect of sodium glucuronate (SG) on osteoporosis (OP). To achieve this aim, the optimal concentration of SG for stimulating MC3T3-E1 osteoblast cells derived from the calvaria of neonatal mice was determined using cell counting kit-8 and alkaline phosphatase (ALP) activity assays. Osteogenic markers were analyzed by qRT-PCR and Western blotting. The histopathological morphology of the tibial tissues was performed using hematoxylin and eosin staining. The levels of bone turnover markers (BTMs) were assessed using enzyme-linked immunosorbent assay (ELISA). SG treatment was found to effectively promote osteoblastic differentiation and mineralization in MC3T3-E1 cells, evidenced by enhanced ALP activity, increased calcium deposition, and upregulated expression of key osteogenic markers including runt-related transcription factor 2 (RUNX2), osteocalcin (OCN), and osteopontin (OPN). Moreover, in ovariectomized rats, a model of postmenopausal OP, SG treatment significantly promoted bone formation, regulated the levels of BTMs, and augmented bone mineral density. Consistently, SG upregulated the expression of osteogenic genes (RUNX2, OCN, and OPN) in bone tissue, further supporting its osteogenic potential. Collectively, these findings suggest that SG possesses the ability to stimulate bone formation and may hold promise as a potential agent for the management of OP.

The farnesoid X receptor (FXR), a nuclear receptor activated by endogenous bile acids, regulates not only bile acid synthesis but also lipid and carbohydrate metabolism. Therefore, FXR ligands, including FXR antagonists, show potential as therapeutic agents for various metabolic diseases. However, the mechanism by which FXR antagonists influence FXR activity is unclear. We previously synthesized an FXR antagonist, FLG249, which reduced the expression of several FXR target genes in the mouse ileum when orally administered and improved lipid metabolism in the liver and ileum of high-fat diet-induced obese mice. In the present study, we aimed to characterize the mechanism by which FLG249 inhibits the interaction of FXR with its coactivators and corepressors. The LanthaScreen^TM time-resolved fluorescence energy transfer assay and two-hybrid assay were used to evaluate the effect of FLG249 on FXR. We found that, upon binding, FLG249 reduced the interaction of FXR with both coactivators and corepressors. This result suggests that the mechanism of FLG249 as a nuclear receptor modulator is distinct from that of previously reported neutral antagonists and inverse agonists of nuclear receptors.

Light stress is a risk factor leading to retinal diseases such as age-related macular degeneration. However, the mechanism underlying the stress response to light in the retina has yet to be elucidated. We have reported that exposure to blue light-emitting diode light induces excessive production of reactive oxygen species and activates the unfolded protein response, robustly increasing activating transcription factor 4 (ATF4) expression. These processes result in photoreceptor cell death. This study investigates the effects of Pentadecyl, a bioactive product obtained from Aurantiochytrium limacinum, on either chemical-induced or blue light-induced endoplasmic reticulum (ER) stress. Pentadecyl suppressed cell death induced by either thapsigargin or tunicamycin in a concentration-dependent manner. Pentadecyl also suppressed the expression of unfolded protein response target genes, including Atf4 and ER chaperones. Consistently, immunoblotting revealed that Pentadecyl suppressed the increased expression of ATF4 at the protein level. Pentadecyl also protected 661W cells from blue light-induced damage but did not protect against hydrogen peroxide (H₂O₂)-induced oxidative stress. These results indicated that Pentadecyl has a novel function that protects against ER stress induced by photodamage.

The human deubiquitinating enzyme ubiquitin-specific peptidase 7 (USP7) has emerged as a promising anti-tumor target, particularly in colorectal cancer, due to its regulation of the MDM2/p53 axis. Through a combination of ubiquitin C-terminal 7-amido-4-methylcoumarin hydrolysis assay and ubiquitin-propargylamide protease profiling, we identified the natural dietary flavonoid quercetin as a potent USP7 inhibitor in both cell-free and cellular contexts. Cellular thermal shift and surface plasmon resonance analyses demonstrated that quercetin is directly bound to USP7. Consistent with USP7 target engagement in cells, quercetin decreased MDM2 levels and subsequently increased the levels of p53. Moreover, quercetin also suppressed colorectal cancer cell proliferation by inducing G2/M cell cycle arrest and inhibiting cell migration. Collectively, our study identified quercetin as a novel and effective USP7 inhibitor with potent anti-colorectal cancer activity, highlighting its therapeutic potential for targeting the USP7-MDM2-p53 axis and warranting further exploration as a promising therapeutic agent in colorectal cancer treatment.

Placental extract (PE) is employed as a skin-whitening agent in Japan, where this material is used in cosmetics and dietary supplements. However, the mechanism of PE's anti-melanogenic activity remains poorly understood. The goal of the present study was to elucidate the mechanism of PE's inhibitory effect on melanogenesis in B16 murine melanoma cells. Specifically, the activity of equine PE (EPE) against tyrosinase and melanogenic proteins was evaluated. The effects of EPE on tyrosinase activity and melanin content were assessed spectrophotometrically. This analysis showed that EPE inhibits melanogenesis in melanoma cells in a dose-dependent manner without affecting cell proliferation. EPE did not directly inhibit the enzymatic activity of tyrosinase. Western blot analysis demonstrated that EPE exposure also led to decreases in the protein levels of tyrosinase and tyrosinase-related protein 1 (TRP-1) in melanoma cells, without affecting the levels of the mRNAs encoding these proteins. This analysis further demonstrated that the EPE-induced depletion of tyrosinase and TRP-1 resulted from the induction, by EPE, of proteasome-mediated proteolytic degradation. Notably, the EPE-induced depletion of tyrosinase and TRP-1 was prevented by joint exposure to EPE and the proteasome inhibitor MG132. Similar experiments showed that the exposure of melanoma cells to MG132 abrogates the inhibition of melanogenesis by EPE. Immunoprecipitation analysis further revealed that EPE induces the ubiquitination of tyrosinase and TRP-1. Taken together, these results suggested that EPE induces proteasomal degradation of tyrosinase and TRP-1 by enhancing the ubiquitination of these targets, leading to the depletion of these proteins and the inhibition of melanogenesis.

Microglia-mediated neuroinflammation plays a critical role in the onset and progression of Alzheimer's disease. In a previous study, we synthesized 6-hydroxy-3'-propyl-[1,1'-biphenyl]-3-propanoic acid (6OHA) based on the structure of magnaldehyde B, a natural compound that our group identified as a retinoid X receptor (RXR) agonist. However, its potential effects on inflammation in microglial cells remain unexplored. In this study, we specifically focused on the early-phase inflammatory responses to lipopolysaccharide (LPS) and evaluated the inhibitory effects of 6OHA on BV-2 microglial cells following 2 h of LPS exposure. Similar to the existing RXR agonist bexarotene (Bex), 6OHA treatment (0.1 and 1 μM) resulted in a dose-dependent decrease in the mRNA levels of proinflammatory mediators, including interleukin-1β (Il1b), Il6, and inducible nitric oxide synthase. However, these effects on proinflammatory mediators were effectively abolished by the RXR antagonist UVI3003. Additionally, 6OHA promoted M2 microglia polarization after 24 h of treatment, as evidenced by the increased mRNA levels of the M2 marker genes arginase-1 (Arg1), C-C motif chemokine ligand 6 (Ccl6), Ccl17, and Ccl22. Notably, 6OHA induced a distinct set of M2 microglial markers compared with IL-4, a known M2 microglial inducer. Furthermore, the transcription of Arg1, a key M2 marker gene, is regulated by retinoic acid receptor/RXR heterodimers and the IL-4 signaling pathway. Collectively, 6OHA suppressed the early inflammatory responses to LPS and promoted M2 microglial polarization through a mechanism distinct from that of IL-4. Therefore, RXR agonists, including 6OHA and Bex, may exhibit dual anti-inflammatory effects and serve as novel modulators of neuroinflammation.

Ergothioneine (ERGO) has antioxidant and anti-inflammatory activities in UV-irradiated skin cells in vitro; however, there is no evidence about the effects of dietary ERGO on UV-induced skin damage or ERGO skin distribution in vivo. This study examined the protective effects of ERGO-rich edible mushrooms Pleurotus species against UVB-induced skin damage and the exposure to ERGO in the plasma and skin. Hos : HR-1 hairless mice were fed with or without freeze-dried cross-bred Pleurotus species (PS) or Pleurotus eringii (PE) and were exposed to UVB. Dietary intake of PS or PE significantly alleviated UVB-induced reductions in skin moisture content, increases in transepidermal water loss and oxidative stress markers, and epidermal thickening at plasma ERGO concentrations of 30-40 μM. Additionally, ingestion of PS significantly suppressed UVB-induced expression of pro-inflammatory cytokines. These results suggest that ingesting PS and PE may protect against UVB-induced skin disorders through antioxidant and anti-inflammatory activities at clinically relevant ERGO concentrations. Ingestion of PS and PE led to an increase in epidermal ERGO concentration to levels that were approx. 100 times higher than the ERGO concentration required for significant suppression of UVB-induced intracellular reactive oxygen species in immortalized human keratinocyte HaCaT cells. This suggests that the beneficial effects of PS and PE may be at least partly due to the antioxidant effects of ERGO in murine skin. Overall, ingestion of ERGO-rich Pleurotus species resulted in efficient distribution of ERGO to the skin and protective effects against UVB-induced skin damage, suggesting that these mushrooms may have beneficial effects in humans.