DWP16001 is currently in a phase 2 clinical trial as a novel anti-diabetes drug for the treatment of type 2 diabetes by selective inhibition of sodium-glucose cotransporter 2. This in vitro study was performed to compare the metabolism of DWP16001 in human, dog, monkey, mouse, and rat hepatocytes, and the drug-metabolizing enzymes responsible for the metabolism of DWP16001 were characterized using recombinant human cytochrome 450 (CYP) and UDP-glucuronosyltransferase (UGT) enzymes expressed from cDNAs. The hepatic extraction ratio of DWP16001 in five species ranged from 0.15 to 0.56, suggesting that DWP16001 may be subject to species-dependent and weak-to-moderate hepatic metabolism. Five phase I metabolites (M1–M5) produced by oxidation as well as three DWP16001 glucuronides (U1–U3) and two hydroxy-DWP16001 (M1) glucuronides (U4, U5), were identified from hepatocytes incubated with DWP16001 by liquid chromatography-high resolution mass spectrometry. In human hepatocytes, M1, M2, M3, U1, and U2 were identified. Formation of M1 and M2 from DWP16001 was catalyzed by CYP3A4 and CYP2C19. M3 was produced by hydroxylation of M1, while M4 was produced by hydroxylation of M2; both hydroxylation reactions were catalyzed by CYP3A4. The formation of U1 was catalyzed by UGT2B7, but UGT1A4, UGT1A9, and UGT2B7 contributed to the formation of U2. In conclusion, DWP16001 is a substrate for CYP3A4, CYP2C19, UGT1A4, UGT1A9, and UGT2B7 enzymes. Overall, DWP16001 is weakly metabolized in human hepatocytes, but there is a potential for the pharmacokinetic modulation and drug–drug interactions, involved in the responsible metabolizing enzymes of DWP16001 in humans.

Immunomodulation is an essential consideration for cell replacement procedures. Unfortunately, lifelong exposure to nonspecific systemic immunosuppression results in immunodeficiency and has toxic effects on nonimmune cells. Here, we engineered hybrid spheroids of mesenchymal stem cells (MSCs) with rapamycin-releasing poly(lactic- co -glycolic acid) microparticles (RAP-MPs) to prevent immune rejection of islet xenografts in diabetic C57BL/6 mice. Hybrid spheroids were rapidly formed by incubating cell-particle mixture in methylcellulose solution while maintaining high cell viability. RAP-MPs were uniformly distributed in hybrid spheroids and sustainably released RAP for ~3 weeks. Locoregional transplantation of hybrid spheroids containing low doses of RAP-MPs (200- to 4000-ng RAP per recipient) significantly prolonged islet survival times and promoted the generation of regional regulatory T cells. Enhanced programmed death-ligand 1 expression by MSCs was found to be responsible for the immunomodulatory performance of hybrid spheroids. Our results suggest that these hybrid spheroids offer a promising platform for the efficient use of MSCs in the transplantation field.

We investigated the in vitro metabolism and estrogenic and antiestrogenic activity of toremifene (TOR), tamoxifen (TAM) and their metabolites to better understand the potential effects of cytochrome P‐450 2D6 (CYP2D6) status on the activity of these drugs in women with breast cancer. The plasma concentrations of TOR and its N‐desmethyl (NDM) and 4‐hydroxy (4‐OH) metabolites during steady‐state dosing with TOR were also determined. Unlike TOR, TAM and its NDM metabolite were extensively oxidized to 4‐OH TAM and 4‐OH‐NDM TAM by CYP2D6, and the rate of metabolism was affected by CYP2D6 status. 4‐OH‐NDM TOR concentrations were not measurable at steady state in plasma of subjects taking 80 mg of TOR. Molecular modeling provided insight into the lack of 4‐hydroxylation of TOR by CYP2D6. The 4‐OH and 4‐OH‐NDM metabolites of TOR and TAM bound to estrogen receptor (ER) subtypes with fourfold to 30‐fold greater affinity were 35‐ to 187‐fold more efficient at antagonizing ER transactivation and had antiestrogenic potency that was up to 360‐fold greater than their parent drugs. Our findings suggest that variations in CYP2D6 metabolic capacity may cause significant differences in plasma concentrations of active TAM metabolites (i.e., 4‐OH TAM and 4‐OH‐NDM TAM) and contribute to variable pharmacologic activity. Unlike TAM, the clinical benefits in subjects taking TOR to treat metastatic breast cancer would not likely be subject to allelic variation in CYP2D6 status or affected by coadministration of CYP2D6‐inhibiting medications.

This study investigated how exposure to per- and polyfluoroalkyl substances (PFAS) influence the levels of thyroid-stimulating hormone (TSH) and free thyroxine (fT4) and the risk of thyroid disease in euthyroid adults. A retrospective cohort study was conducted using data from 181 euthyroid Korean adults (59.4 ± 8.8 years, 33.1 % male) from the Korean Genome and Epidemiology Study. Serum concentrations of four PFAS (PFOA, PFOS, PFNA, and PFHxS) were measured using liquid chromatography-mass spectrometry, and a relative potency factor-based cumulative PFAS exposure (Cmix) was calculated. Linear regression and Bayesian Kernel Machine Regression (BKMR) were used to assess the associations between PFAS exposure and thyroid hormone levels. Cox regression analysis was conducted to assess the risk of thyroid disease during a 3.6 ± 1.3-year follow-up. Serum PFOS levels were negatively correlated with TSH, showing a reverse J-shaped dose-response relationship. PFOS and PFNA exhibited inverse J-shaped positive associations with fT4. Mixed PFAS exposure (lnCmix) significantly reduced TSH levels in females (adjusted linear regression coefficient -0.56, 95 % CI -1.03 ∼ -0.09, p = 0.021) but had no significant effect on fT4. In the BKMR analysis, PFOA, PFOS, and PFNA were identified as factors that influenced TSH levels, exhibiting a non-significant decreasing pattern of TSH upon mixed exposure. During follow-up, mixed PFAS exposure increased the risk of thyroid disease (adjusted HR 9.53, 95 % CI 1.29-70.6, p = 0.027). Mixed PFAS exposure decreases TSH levels, particularly in women, and increases the risk of thyroid disease. Further research is needed to assess the nonlinearity between exposure and outcomes, as well as to evaluate mixed exposures.