Biological & pharmaceutical bulletin最新文献

Leydig cells are testosterone synthesis cells in testes, a process tightly regulated by luteinizing hormone (LH) through the activation of steroidogenic enzymes such as steroidogenic acute regulatory protein (StAR) and 3-beta-hydroxy-Delta5-steroid dehydrogenase (3β-HSD). While calcium/calmodulin-dependent protein kinase 2 (CAMK2) is known to modulate diverse cellular processes, including hormone signaling, its role in testosterone production remains unclear. In this study, we investigated the expression and functions of CAMK2 in mouse testes, focusing on its potential involvement in testosterone synthesis. Our findings demonstrate that CAMK2 expression progressively increases from postnatal day 1 (PND 1) to adulthood. Pharmacological inhibition of CAMK2 with KN-62 markedly reduced serum testosterone levels and downregulated the expression of key steroidogenic enzymes, including StAR and 3β-HSD, at both mRNA and protein levels. In vitro experiments using primary Leydig cells further confirmed that CAMK2 inhibition suppressed testosterone production and steroidogenic enzyme expression, particularly after prolonged (12-24 h) KN-62 treatment. Additionally, CAMK2 expression was upregulated in response to LH stimulation, suggesting its involvement in LH-mediated signaling pathways, potentially through modulation of the epidermal growth factor receptor (EGFR)/extracellular signal-regulated kinase 1/2 (ERK1/2) cascade. These findings demonstrate that CAMK2 positively regulates testosterone synthesis in Leydig cells, likely via the EGFR/ERK1/2 cascade. The results of this study enhance our understanding of the regulation of testosterone synthesis and identifies CAMK2 as a potential therapeutic target for male reproductive endocrine disorders.

Oral administration is the preferred route for drug administration owing to a high level of patient compliance and suitability for long-term treatment. However, drugs with a molecular weight of >1000 Da such as peptide-based therapeutics generally exhibit poor absorption from the gastrointestinal tract. In this study, we evaluated the potential of ionic liquids to enhance the oral absorption of mid-sized molecules such as dextran, which has a size of 10 kDa. In this study, the ionic liquids we tested enhanced the oral absorption of 10 kDa mid-sized dextran. Among the ionic liquids we tested, d/l-Lactic acid-trometamol ([Lac][Tris])-based ionic liquids consistently yielded higher values for maximum concentration (C_max; 153.9 ± 11.0 nmol/L) of dextran as well as for the area under the curve representing 0-2 h (AUC_{0-2 h}; 228.9 ± 54.1 nmol × h/L) compared with that of the other ionic liquids tested. The [Lac][Tris] = 5 : 1 ionic liquid achieved relatively higher values for both C_max and AUC_{0-2 h}. Interestingly, the observed oral absorption enhancement effect by the [Lac][Tris] = 5 : 1 ionic liquid for mid-sized molecules depended on the concentration of dextran (10 kDa). These results show that ionic liquid formulations can overcome the intestinal barrier and lead to systemic absorption of mid-sized molecules with molecular weights. Although further optimizations aimed at translating ionic liquid technology to the oral delivery of peptide drugs must be required, our results could expand the utility and possibility of ionic liquids as an oral absorption enhancer for mid-sized molecules such as peptides.

The cytosolic translocation of the membrane-associated CYP3A2 protein was examined in male and female rats to evaluate the ubiquitin-dependent protein degradation. In the experiments, the cytosol and membrane fractions were prepared from pooled rat liver tissues, and the amount of CYP3A2 protein in those fractions was determined by Western immunoblotting. The CYP3A2 protein detected in the cytosol fraction was shown to be ubiquitinated, and the apparent translocation ratio of the CYP3A2 protein from the membrane to the cytosol was calculated to be 0.58 in male control rats. The translocation ratio was then evaluated in male rats undergoing CYP3A2 induction. When male rats were treated with 80 mg/kg of dexamethasone (DEX), the translocation ratio decreased to 0.05, but the ratio was barely affected in male rats treated with 1.6 mg/kg of DEX, indicating that the cytosolic translocation of the CYP3A2 protein had a saturable nature. After that, the CYP3A2 translocation was examined in female rats with induced CYP3A2 protein, as the protein was known to be expressed in a male-specific manner. In female rats treated with 80 mg/kg of DEX, the translocation ratio was 0.04, but in those treated with 1.6 mg/kg of DEX, the ratio increased to 1.24, approximately 2 times larger than that in male control rats. It appeared that the DEX-induced CYP3A2 protein in female rats underwent expeditious degradation, presumably reflecting a difference in the mechanisms regulating the hepatic expression of the CYP3A2 protein in male and female rats.

Proton pump inhibitors (PPIs) are implicated in the progression of chronic kidney disease (CKD), but the mechanism behind this is unclear. PPIs are known to inhibit organic anion transporters (OATs) and affect intestinal microbiota. PPI use may influence serum concentrations of indoxyl sulfate (IS), a uremic toxin that contributes to CKD. This study compares serum IS concentrations between Japanese patients receiving long-term PPI prescriptions and those receiving non-PPIs, evaluating the effect of long-term PPI therapies on serum IS concentrations. This single-center, cross-sectional study included patients with an estimated glomerular filtration rate (eGFR) of 15 to 44 mL/min/1.73 m,² who attended an outpatient visit at a nephrology and/or diabetes department between October 2022 and December 2023. Serum IS concentrations were measured by HPLC. The analysis included 29 patients in the PPI group and 28 in the non-PPI group; serum IS concentrations were significantly higher in the PPI group [median (interquartile range) 15.37 (9.69-19.80) µM] and non-PPI group [median (interquartile range) 10.66 (6.97-14.19) µM], p = 0.03. Multiple regression analysis was performed, linking prescription of PPIs and lower eGFR to higher serum IS levels. This study highlights an apparent association of long-term prescriptions of PPIs with high serum IS concentrations. However, more detailed studies are required to evaluate the contribution of intestinal microbiota and diet to this phenomenon.

Immune checkpoint inhibitors (ICIs), essential in cancer therapy, can cause severe immune-related adverse events (irAEs), including myocarditis with a high fatality rate. Currently, the pathogenesis, biomarkers, and risk factors of ICI-induced myocarditis (ICIM) are not fully understood. This exploratory study aimed to develop machine learning-based models to predict the onset of ICIM within 3 months of starting ICI therapy, using a large health insurance database. The models were constructed using the Light Gradient Boosting Machine (LightGBM) and Random Forest algorithms, incorporating clinical variables such as comorbidities and prior medication classifications. In this study, a strategy combining undersampling and bagging was used to minimize the impact of highly imbalanced datasets. The Random Forest model demonstrated superior performance compared with the LightGBM model, and the SHapley Additive exPlanations (SHAP) analysis for the Random Forest model revealed that the concurrent use of ICIs was the most important variable for predictions. Although predictive performance remains limited (AUROC ≈ 0.63), this exploratory framework demonstrates the feasibility of developing data-driven risk prediction models for ICIM. Future studies with expanded datasets and integration of laboratory parameters are warranted to improve predictive accuracy and potential clinical applicability.

Deltex E3 ubiquitin ligase 3L (DTX3L) is a well-established ubiquitin ligase implicated in various cancers, but its role in nasopharyngeal carcinoma (NPC) progression remains elusive. In this study, we confirmed for the first time that DTX3L was highly expressed in C666-1 and NPC/HK1 NPC cells. DTX3L overexpression promoted NPC cell proliferation, invasion, and migration. Conversely, DTX3L knockdown suppressed these malignant phenotypes. Notably, DTX3L activated the β-catenin pathway, as evidenced by increased β-catenin nuclear translocation, increased transcriptional activity, and elevated expression of its downstream target c-Myc. Mechanistically, we identified an upstream regulatory axis in which the oncogenic long noncoding RNA H19 acted as a molecular sponge for miR-423-5p, thereby alleviating the miR-423-5p-mediated repression of DTX3L. Dual-luciferase reporter assays confirmed that miR-423-5p directly targeted both DTX3L and H19, supporting the presence of a competitive endogenous RNA (ceRNA) network. Furthermore, rescue experiments demonstrated that DTX3L knockdown largely abolished the proliferative advantage conferred by H19 overexpression. Collectively, the results of our study revealed that the H19/miR-423-5p/DTX3L axis is a novel ceRNA-driven mechanism that promotes NPC progression via activation of β-catenin signaling.

Using a large health insurance database in Japan, we examined the real-world usage of budesonide enteric-coated capsules (BUD) in treating Crohn's disease. We analyzed data from the Japan Medical Data Center claims database for Crohn's disease patients prescribed BUD from April 2016 to March 2021, focusing on prescription status, adverse events (AEs), monitoring tests, and concomitant medications over 2 years following BUD initiation. Patients were categorized into two groups based on BUD usage duration: ≤1 year and >1 year. Of the 7364 registered patients, 1049 (14.2%) were prescribed BUD. Among the 562 followed for 2 years, 505 (89.9%) used BUD for ≤1 year and 57 (10.1%) for >1 year. Over 70% of the patients used at least one biologic, and more than 20% used at least two. The proportions of new thiopurine initiation were 22 and 9% in the ≤1-year and >1-year groups, respectively (p = 0.0181). We did not identify any obvious increase in AEs from long-term BUD use within the confines of our study design. However, regardless of prescription duration, over half of the patients lacked hepatitis B virus screening, glycated hemoglobin measurement, adrenal function quantification, or bone densitometry. Usage of strong CYP3A4 inhibitors was more frequent among patients in the BUD >1-year group. This study revealed that numerous Japanese patients received long-term BUD prescriptions. Although no apparent increase in AEs from long-term BUD was detected, we identified inadequate monitoring of AEs and drug interactions, as well as insufficient use of steroid-sparing agents.

Intravenous administration of branched-chain amino acid (BCAA)-enriched solution is contraindicated in patients with severe chronic kidney disease (CKD). However, there have been no reports on its risks in patients with mild-to-moderate CKD. In this study, we compared the incidence of acidosis between patients with mild-to-moderate CKD (estimated glomerular filtration rate [eGFR] ≥30 and <60 mL/min/1.73 m²) and patients without CKD (eGFR ≥60 mL/min/1.73 m²) who received intravenous BCAA-enriched solution after propensity score matching (PSM). A retrospective analysis of the medical records at Hiroshima University Hospital identified 608 patients who were treated with intravenous BCAA-enriched solutions between January 2005 and December 2010. The laboratory data for these patients were analyzed. After PSM, the incidence of acidosis was compared between 91 pairs of patients with mild-to-moderate CKD or no CKD using Fisher's exact test. The incidence of acidosis was significantly higher in the mild-to-moderate CKD group than in the non-CKD group (36.3 vs. 18.7%, p <0.05). The odds ratio for the incidence of acidosis in patients with mild-to-moderate CKD was 2.48 (95% confidence interval 1.26-4.88). Kaplan-Meier curves showed that the cumulative incidence of acidosis increased soon after initiation of intravenous BCAA-enriched solution in both groups. In conclusion, intravenous BCAA-enriched solution can cause acidosis even in patients without CKD, with an increased risk in patients with mild-to-moderate CKD, in whom this agent is not contraindicated. Therefore, intravenous BCAA-enriched solution should be administered with caution in patients with CKD, regardless of its severity.

Mineralocorticoid receptor (MR) blockers reduce cardiovascular complications as MRs play a crucial role in cardiovascular regulation. Diabetic cardiovascular complications are caused by vascular endothelial dysfunction. This study used a type 2 diabetic mouse model (DM) to investigate whether esaxerenone (ESAX), an MR blocker, ameliorates vascular endothelial dysfunction. ESAX (3 mg/kg/d) was administered via diet to KK-Ay mice or C57BL/6J mice, a nondiabetic control (Control), for 8 weeks, and metabolic parameters and blood pressure were measured. Vascular responses of the aortic segments were analyzed with acetylcholine, sodium nitroprusside, UK14304, or phenylephrine (PE). The other aortas were used for Western blot analysis. DM mice exhibited higher plasma glucose, insulin, metabolic parameters, and blood pressure levels than those of the Control mice. Parameters that did not include blood pressure were unaltered by DM or ESAX-administered DM (DM + ESAX). However, DM impaired UK14304-induced endothelial-dependent relaxation and nitric oxide production and elevated PE-induced contraction. ESAX administration ameliorated endothelial dysfunction and improved the protein kinase B (Akt) phosphorylation under α₂-agonist UK14304 stimulation in the aorta from DM mice compared with that of the Control mice. However, ESAX did not recover the increased G protein-coupled receptor kinase 2 (GRK2) expression and activity in the DM aorta. Furthermore, the DM-induced phosphorylation of serum and glucocorticoid-regulated kinase 1 (SGK1) was inhibited by ESAX. Overall, ESAX attenuates the development of DM-induced endothelial dysfunction by reducing SGK1 activity and enhancing Akt activity without affecting the GRK2 pathway. These results suggest that the vascular protective effects of ESAX could be employed for diabetic vascular complications.

The optimal pharmacokinetics (PK) of orally administered nanoparticles (NPs) varies depending on their application (e.g., drug delivery, adsorbent, and adjuvant). Therefore, engineering NPs to achieve optimal PK is essential for the development of drug designs. Some studies have demonstrated that individual NP factors change the intestinal absorption of NPs; however, no technology has been established to control the biodistribution of orally administered NPs. In this study, a database about the influence of NP characteristics on biodistribution after oral administration was provided. A library of N-isopropylacrylamide polymer NPs with various characteristics that could influence the biodistribution after oral administration, such as size, flexibility, hydrophobicity, surface charges, and surface chemistries, were prepared. NPs with various sizes were synthesized by tuning the surfactant concentration only during synthesis, whereas NPs with different flexibility, hydrophobicity, surface charge, and surface chemistry were synthesized by feeding the corresponding functional monomer. The total amount of NPs accumulated in the organs decreased with increasing NP size, rigidity, hydrophobicity, electric potential (whether positive or negative), and polyethylene glycol modification. The results indicated that the absorption of orally administered NPs can be controlled by optimizing the characteristics of NP such as size, flexibility, hydrophobicity, surface charge, and surface chemistry. The results of this study will provide useful information to design NP formulations.