Chronic kidney disease (CKD) is closely related to disorders of various organs of the body and is also a factor in increasing social security costs such as medical costs for dialysis. Multiprofessional public health associations in Kushiro City jointly manage CKD-targeted action as “Kushiro CKD network” composed of medical/dental physicians, nurses, nutritionists and pharmacists. Pharmacists have played a central role in affixing a CKD sticker to a patient’s medicine notebook when the patient’s estimated glomerular filtration rate (eGFR) <45 mL/min/1.73 m², in order to highlight the risk of CKD for those patients and related medical staff. There are many drugs that require dose reduction considering for renal function, but we had found cases where renal function was not monitored and pharmaceutical dispensation adjusted before the CKD network started. Therefore, we took this opportunity to investigate the impact of CKD stickers on pharmacists’ work. During the period from August 2018 to August 2021, about 3200 CKD stickers were affixed by pharmacists, and about 4500 cases of decreased renal function were detected at pharmacies. In addition, there were 334 cases in which renal function deterioration was identified by the CKD stickers and led to further inquiries, of which 265 cases, or about 80%, resulted in prescription changes. Based on these results, it is considered that CKD stickers are effective method for pharmacies understand renal function deterioration and conduct appropriate prescription reviews. Finally, and perhaps most importantly, the use of CKD stickers can help assure that patients with renal impairment care treated with appropriate medication doses.

Chronic activation of the nuclear receptor, peroxisome proliferator-activated receptor alpha (PPARA), causes hepatocellular proliferation and increases the incidence of hepatocellular carcinoma in rodents. However, the molecular mechanisms underlying hepatocyte proliferation by activated PPARA remain ambiguous. This review focuses on the genes repressed by PPARA and describes the mechanism by which it promotes hepatocyte proliferation in mice. PPARA undergoes autoinduction, leading to its overexpression by an agonist. PPARA subsequently activates the E2F transcription factor 8 (E2f8), which then activates the ubiquitin-like protein containing the PHD and RING finger domains 1 (Uhrf1). UHRF1, in complex with histone deacetylase 1 and DNA methyltransferase 1, stimulates DNA methylation and recruitment of histone H3 containing trimethylated lysine 9 to the promoters of specific target genes, including E-cadherin/cadherin 1 (Cdh1), resulting in their downregulation. Decreased expression of CDH1 stimulates Wnt signaling, upregulation of oncogenes, including Myc and the cell cycle control genes, cyclin D1 and Jun, and enhances hepatocyte hyperproliferation. Therefore, the PPARA–E2F8–UHRF1–CDH1–Wnt signaling axis is involved in the epigenetic regulation of hepatocyte proliferation. This review provides insights into the mechanisms underlying hepatocarcinogenesis induced by non-genotoxic substances.

Nanoplastics (NPs) are plastic fragments that are small enough to be absorbed by organisms through ingestion or inhalation. Recent studies indicate that nanoplastics can be ubiquitous in the environment, and there are growing concerns regarding the impacts of nanoplastics on the health of humans and other organisms. However, quantitative information on nanoplastics in the environment is still very limited, and most previous toxicity studies have used only polystyrene (PS) particles because of a lack of appropriate model particles of other plastics. We developed a nanoprecipitation-based method for the preparation of nanoplastic particles of five major polymers: low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), polyvinyl chloride (PVC), and polystyrene. A major advantage of our method is that the nanoplastic particles are prepared without using reagents that can remain in the particles as impurities. Analysis of the prepared particles’ molecular weight (M_w) distributions, crystallinities, and thermal properties revealed that their compositions and constitutions were within the general ranges for commercial products. The mechanisms underlying the formation of low-density polyethylene particles via our method were investigated by means of a simple population balance model, and particle diameter was found to be linearly correlated with the suspension density of the nanoplastic dispersion up to 0.4 mg·mL⁻¹. Future studies should focus on improving our method to allow for precise, scale-independent production of nanoplastic particles. Methods for the preparation of labeled particles are also needed so that such particles can be used in nanoplastic risk assessments.

Microplastics are small pieces of plastic that are less than 5 mm in length. These plastics have been detected in various environments, including the ocean, soil, and air. Their abundance have raised concerns regarding their potential effects on living organisms, including humans. The surface of microplastics degrades due to external factors such as ultraviolet rays and water waves in the environment. Therefore, assessing the biological impact of microplastics and considering their state of degradation is important. Among the physical properties of microplastics, we focused on the chemical degradation of microplastics. Specifically, we used vacuum ultraviolet (VUV) light to accelerate the degradation of polyethylene (PE) and prepared PE samples representing the degradation of PE to varying degrees. The surface properties of PE samples prepared using VUV were similar to those obtained from the environment. Cytotoxicity tests were then used to evaluate the effects of undegraded and degraded PE on cells. We found that the severity of cytotoxicity increased with the extent to which the PE would have been degraded, suggesting that the degree of degradation is strongly linked to the severity of the observed deleterious effects on living organisms. In conclusion, this finding contributes to our understanding of the effects of polyethylene microplastics on the human body.

Microplastics (MPs), defined as plastic particles less than 5 mm in size, are ubiquitous in the environment. The accumulation of MPs in various environmental compartments, such as the ocean, soil, and air, has raised considerable concerns regarding their impact on ecological systems, including marine life and human health. Notably, MPs have been detected in marine organisms such as shellfish and fish, and have even been found in the human body, including in the blood and placenta. Moreover, considering that MPs have been detected in drinking water, human exposure to these particles in daily life is inevitable. To assess the risk posed by MPs to human health, it is essential to consider their physiological and chemical properties, including size, shape, surface modification, and material composition. However, current risk analyses focus primarily on spherical MPs with smooth surfaces, which differ substantially from most of the MPs detected in the environment. Environmental factors, such as ocean waves and ultraviolet radiation, alter the properties of MPs, including size, shape, and surface characteristics. In this review, we summarize current research on MPs, with a particular emphasis on the effects of MP degradation on human health. Furthermore, we generated MPs with surface degradation and evaluated their impact on cell toxicity, along with the underlying biological mechanisms.

Tannins are a group of polyphenols that possess the ability to precipitate proteins, causing an undesirable astringent taste by interacting with salivary peptides. This interaction deactivates the digestive enzymes; therefore, tannins are considered as plant defense substances. The health benefits of tannins and related polyphenols in foods and beverages have been demonstrated by biological and epidemiological studies; however, their metabolism in living plants and the chemical changes observed during processing of foods and medicinal herbs raises some questions. This review summarizes our studies concerning dynamic changes observed in tannins. Ellagitannins present in the young leaves of Camellia japonica and Quercus glauca undergo oxidative degradation as the leaves mature. Similar oxidative degradation is also observed in whiskey when it is kept for aging in oak barrels, and in decaying wood caused by fungi in natural forests. In contrast, ellagitannins have been observed to undergo reduction in the leaves of Carpinus, Castanopsis, and Triadica species as the leaves mature. This phenomenon of reductive metabolism in leaves enabled us to propose a new biosynthetic pathway for the most fundamental ellagitannin acyl groups, which was also supported by biomimetic synthetic studies. Polyphenols undergo dynamic changes during the process of food processing. Catechin in tea leaves undergo oxidation upon mechanical crushing to generate black tea polyphenols. Though detailed production mechanisms of catechin dimers have been elucidated, structures of thearubigins (TRs), which are complex mixtures of oligomers, remain ambiguous. Our recent studies suggested that catechin B-ring quinones couple with catechin A-rings during the process of oligomerization.

My research focused on the effects of various drugs on (1) dopamine formation from p-tyramine catalyzed by polymorphic cytochrome P450 (CYP or P450) 2D6 variants and (2) endogenous steroid hormone hydroxylation catalyzed by CYP3A subfamily members (CYP3A4, CYP3A5, CYP3A7). The activation (cooperativity) of metabolic reactions catalyzed by P450s was especially emphasized. The effects of various psychotropic agents on dopamine formation from p-tyramine, catalyzed by wild-type CYP2D6.1 and CYP2D6 variants, including CYP2D6.2 (Arg296Cys;Ser486Thr), CYP2D6.10 (Pro34Ser;Ser486Thr), and CYP2D6.39 (Ser486Thr) were compared. Michaelis (K_m) and inhibition (K_i) constants of the psychotropic agents in the presence of CYP2D6.10 were higher than those observed in the presence of other CYP2D6 variants. Fluvoxamine, fluoxetine, milnacipran, and haloperidol activated CYP2D6-catalyzed dopamine formation [decreasing the K_m and/or increasing the maximal velocity (k_cat)], and this activation was CYP2D6 variant-dependent. Regarding the CYP3A subfamily, the effects of various compounds including endogenous steroid hormones on the 6β-hydroxylation of steroid hormones, such as testosterone, progesterone, and cortisol, were determined; it was found that testosterone, dehydroepiandrosterone, and/or α-naphthoflavone activated 6β-hydroxylation of cortisol and/or progesterone, but the effects varied in the presence of different CYP3A subfamily members. Further studies are required to confirm the mechanisms and therapeutic relevance of these activation phenomena.

Normal differentiation and proliferation of cells are essential for maintaining homeostasis. Following the successful completion of whole genome sequencing, protein modification has been attracted increasing attention in order to understand the roles of protein diversification in protein function and to elucidate molecular targets in mechanisms of signal transduction. Vitamin A is an essential nutrient for health maintenance. It is present as β-carotene in green and yellow vegetables and retinyl ester in animal products and absorbed into the body from the intestines. After ingestion, it is converted to retinol and oxidized in target cells to retinal, which plays critical roles in vision. It is then further oxidized to retinoic acid (RA), which exhibits a number of effects prior to being metabolized by cytochrome P450 and excreted from the body. Since RA exhibits cell differentiation-inducing actions, it is used as a therapeutic agent for patients with acute promyelocytic leukemia. The current paper describes: (1) HL60 cell differentiation and cell differentiation induction therapy by RA; (2) roles played by RA and retinal and their mechanisms of action; (3) retinoylation, post-translational protein-modified by RA, a novel non-genomic RA mechanism of action without RA receptor; (4) new actions of β-carotene and retinol in vivo and (5) potent anticancer effects of p-dodecylaminophenol (p-DDAP), a novel vitamin A derivative created from the RA derivative fenretinide. We propose that nutritional management of vitamin A can be effective at preventing and treating diseases, and that p-DDAP is a promising anticancer drug.

Home healthcare services provided by community pharmacists are essential for maintaining community care, especially in Japan’s aging population. Personnel shortage in pharmacies is occasionally cited as the reason why pharmacies are unable to provide home healthcare services. This study examined the relationship between the number of pharmacists in each pharmacy and the provision of home healthcare services. The number of full-time and part-time pharmacists per pharmacy has a positive impact on the provision of home healthcare services. Moreover, the larger the number of pharmacists per pharmacy, the easier it is for the pharmacy to provide home healthcare services. With regard to pharmacies with one full-time pharmacist, there are more pharmacies that provide home healthcare services when the population density of municipalities where the pharmacy is located is high. However, the impact of the number of pharmacists on population density became obscure when the number of full-time pharmacists per pharmacy was three or more. Taken together, these findings indicate that the provision of home healthcare services by pharmacies is related to the number of pharmacists per pharmacy and the population density of the area. This could have implications for widening regional disparities in home healthcare services.

Xanthan gum-based food thickeners have been reported to potentially interfere with tablet disintegration. Loxoprofen sodium (LOX) is widely used as an antipyretic analgesic and is expected to provide rapid pain relief. In this study, we aimed to investigate the impact of a xanthan gum-based food thickener on LOX tablet disintegration. We used four different brands each of medical and OTC-LOX tablets, each containing 60 mg of LOX as the sole active ingredient. Depending on the brand, tablet hardness varied between 50.1–96.6 N and was not associated with the disintegration time. Disintegration times for medical tablets not immersed in the food thickener were 536±215, 621±159, 348±22, 369±42 s and for OTC tablets, were 358±20, 336±13, 292±13, 172±27 s. Immersion in the food thickener for 15 min reduced medical tablet disintegration time to 177±46 and 233±150 s (the third and fourth brands were disintegrated during immersion), and that for OTC tablets to 77±40, 75±110, and 37±85 s (the fourth brand was disintegrated during immersion). Despite each tablet containing different pharmaceutical additives, no correlation was found between disintegration time and presence of superdisintegrants. The OTC tablet with a light anhydrous silicic acid coating exhibited the shortest disintegration time. Thus, the disintegration time of LOX tablets is accelerated when immersed in the xanthan gum-based food thickener, potentially leading to rapid pain relief for patients.

We experienced a case in which long-term use of nivolumab in a patient with a history of ulcerative colitis led to disease control of gastric cancer. The case is a 77-year-old man. The patient had a history of ulcerative colitis and remained in remission on mesalazine 1500 mg/d. With continuous monitoring, nivolumab could be continued up to 16 courses, but was withdrawn due to the appearance of diarrhea (grade 1) and bloody stools, which was relieved with prednisolone (PSL) 40 mg/d. After two more courses, diarrhea (grade 3) appeared again, which improved with PSL 60 mg/d and increased dose of mesalazine. It is difficult to distinguish whether colitis that occurs after nivolumab administration is due to relapse exacerbation or irAE. The onset of irAE colitis is often reported within 3 months, and the fact that this patient developed irAE colitis after 8 months, despite having ulcerative colitis, is considered novel. In the future, we hope to accumulate cases so that immune checkpoint inhibitors can be used safely in patients with ulcerative colitis, and to establish appropriate methods for their use.