Design, synthesis and bioactivity evaluation of isobavachin derivatives as hURAT1 inhibitors for hyperuricemia agents.

Previously, we reported a novel natural scaffold compound, isobavachin (4',7-dihydroxy-8-prenylflavanone), as a highly potent hURAT1 inhibitor with anti-hyperuricemia effect. However, the structure-activity relationship remains unknown and the poor pharmacokinetic (PK) parameters may limit further clinical use. Herein, a series of isobavachin derivatives were rationally designed and synthesized to explore the structure-activity relationship of isobavachin target hURAT1, and to improve their PK properties. Among them, compounds 15d, 15f, 15g, 27b and 27d showed promising hURAT1 inhibitory activities, which could comparable to that of isobavachin (IC50 = 0.24 µM). In addition, 27b also inhibited another urate reabsorption transporter GLUT9 with an IC50 of 4.47 µM. Compound 27b displayed greater urate-lowering activity in a hyperuricemia mouse model at a dose of 10 mg/kg compared to isobavachin and lesinurad. Overall, our results suggest that compound 27b represents a novel, safe hURAT1 and GLUT9 dual-target inhibitor with excellent drug availability and is worthy of further investigation as an anti-hyperuricemia agent.

Antidepressant effect of carvedilol on streptozotocin-induced diabetic peripheral neuropathy mice by altering gut microbiota.

RATIONALE: Although diabetic peripheral neuropathic pain (DPNP) and depression have been recognized for many years, their co-morbidity relationship and effective treatment choices remain uncertain. OBJECTIVES: To evaluate the antidepressant effect of carvedilol on streptozotocin-induced DPNP mice, and the relationship with gut microbiota. METHODS: The hyperalgesia and depressive behaviors of mice with comorbidity of DPNP and depression were confirmed by pain threshold of the mechanical sensitivity test (MST), immobility time of the tail suspension test (TST) and the forced swimming test (FST). The anti-depressive effect and fecal gut microbiota composition were studied in DPNP mice treated with carvedilol (10 mg/kg/day), and the relationships between them were analyzed by Spearman's correlation. RESULTS: Depression was successfully induced in DPNP mice. Carvedilol can reverse the decreased mechanical pain threshold and relieve the depressive behaviors of DPNP mice, while increasing the abundance of Prevotella, Ruminococcus, Helicobacter and Desulfovibrio, and decreasing the abundance of Akkermansia and Allobaculum. CONCLUSIONS: Carvedilol can alleviate the mechanical hyperalgesia and alter gut microbiota to ameliorate the depression-like behaviors which induced by DPNP.

Pulmonary and renal long COVID at two-year revisit.

This study investigated host responses to long COVID by following up with 89 of the original 144 cohorts for 1-year (N = 73) and 2-year visits (N = 57). Pulmonary long COVID, characterized by fibrous stripes, was observed in 8.7% and 17.8% of patients at the 1-year and 2-year revisits, respectively, while renal long COVID was present in 15.2% and 23.9% of patients, respectively. Pulmonary and renal long COVID at 1-year revisit was predicted using a machine learning model based on clinical and multi-omics data collected during the first month of the disease with an accuracy of 87.5%. Proteomics revealed that lung fibrous stripes were associated with consistent down-regulation of surfactant-associated protein B in the sera, while renal long COVID could be linked to the inhibition of urinary protein expression. This study provides a longitudinal view of the clinical and molecular landscape of COVID-19 and presents a predictive model for pulmonary and renal long COVID.

Gut Microbiota Affects Mouse Pregnane X Receptor Agonist Pregnenolone 16α-Carbonitrile-Induced Hepatomegaly by Regulating Pregnane X Receptor and Yes-Associated Protein Activation.

Pregnane X receptor (PXR) is essential in the regulation of liver homeostasis, and the gut microbiota is closely linked to liver physiologic and pathologic status. We previously found that activation of PXR significantly promotes liver enlargement through interaction with yes-associated protein (YAP). However, whether gut microbiota contributes to PXR-induced hepatomegaly and the involved mechanisms remain unclear. In this study, C57BL/6 mice were administered the mouse-specific agonist pregnenolone 16α-carbonitrile (PCN) for 5 days. Depletion of gut microbiota was achieved using broad-spectrum antibiotics (ABX) and fecal microbiota transplantation (FMT) was performed to restore the gut microbia. The composition of gut microbiota was analyzed by 16S rRNA sequencing, while the expression of PXR, YAP, and their downstream target genes and proteins were assessed. The results indicated that PCN treatment altered the composition and abundance of specific bacterial taxa. Furthermore, depletion of gut microbiota using ABX significantly attenuated PCN-induced hepatomegaly. FMT experiments further demonstrated that the fecal microbiota from PCN-treated mice could induce liver enlargement. Mechanistic studies revealed that ABX treatment impeded the PXR and YAP activation induced by PCN, as evidenced by decreased expression of PXR, YAP, and their downstream targets. Moreover, alterations in PXR and YAP activation were likely contributing to hepatomegaly in recipient mice following FMT from PCN-treated mice. Collectively, the current study demonstrated that gut microbiota is involved in PCN-induced hepatomegaly via regulating PXR and YAP activation, providing potential novel insights into the involvement of gut microbiota in PXR-mediated hepatomegaly. SIGNIFICANCE STATEMENT: This work describes that the composition of gut microbiota is altered in mouse pregnane X receptor (PXR) agonist pregnenolone 16α-carbonitrile (PCN)-induced hepatomegaly. Treatment with an antibiotic cocktail depletes the intestinal microbiota, leading to the impairment of liver enlargement caused by PCN. Additionally, fecal microbiota transplantation from PCN-treated mice induces liver enlargement. Further study revealed that gut microbiota is involved in hepatomegaly via regulating PXR and yes-associated protein activation.

Discovery of digallic acid as XOD/URAT1 dual target inhibitor for the treatment of hyperuricemia.

The development of XOD/URAT1 dual target inhibitors has emerged as a promising therapeutic strategy for the management of hyperuricemia. Here, through virtual screening, we have identified digallic acid as a novel dual target inhibitor of XOD/URAT1 and subsequently evaluated its pharmacological properties, pharmacokinetics, and toxicities. Digallic acid inhibited URAT1 with an IC50 of 5.34 ± 0.65 µM, which is less potent than benzbromarone (2.01 ± 0.36 µM) but more potent than lesinurad (10.36 ± 1.23 µM). Docking and mutation analysis indicated that residues S35, F241 and R477 of URAT1 confer a high affinity for digallic acid. Digallic acid inhibited XOD with an IC50 of 1.04 ± 0.23 µM. Its metabolic product, gallic acid, inhibited XOD with an IC50 of 0.91 ± 0.14 µM. Enzyme kinetic studies indicated that both digallic acid and gallic acid act as mixed-type XOD inhibitors. It shares the same binding mode as digallic acid, and residues E802, R880, F914, T1010, N768 and F1009 contribute to their high affinity. The anion group (carboxyl) of digallic acid contribute significantly to its inhibition activity on both XOD and URAT1 as indicated by docking analysis. Remarkably, at a dosage of 10 mg/kg in vivo, digallic acid exhibited a stronger urate-lowering and uricosuric effect compared to the positive drug benzbromarone and lesinurad. Pharmacokinetic study indicated that digallic acid can be hydrolyzed into gallic acid in vivo and has a t1/2 of 0.77 ± 0.10 h. Further toxicity evaluation indicated that digallic acid exhibited no obvious renal toxicity, as reflected by CCK-8, biochemical analysis (CR and BUN) and HE examination. The findings of our study can provide valuable insights for the development of XOD/URAT1 dual target inhibitors, and digallic acid deserves further investigation as a potential anti-hyperuricemic drug.

Piperine Improves Hyperuricemic Nephropathy by Inhibiting URAT1/GLUT9 and the AKT-mTOR Pathway.

Uncontrolled hyperuricemia often leads to the development of hyperuricemic nephropathy (HN), characterized by excessive inflammation and oxidative stress. Piperine, a cinnamic acid alkaloid, possesses various pharmacological activities, such as antioxidant and anti-inflammatory effects. In this study, we intended to investigate the protective effects of piperine on adenine and potassium oxonate-induced HN mice and a uric-acid-induced injury model in renal tubular epithelial cells (mRTECs). We observed that treatment with piperine for 3 weeks significantly reduced serum uric acid levels and reversed kidney function impairment in mice with HN. Piperine (5 µM) alleviated uric acid-induced damage in mRTECs. Moreover, piperine inhibited transporter expression and dose-dependently inhibited the activity of both transporters. The results revealed that piperine regulated the AKT/mTOR signaling pathway both in vivo and in vitro. Overall, piperine inhibits URAT1/GLUT9 and ameliorates HN by inhibiting the AKT/mTOR pathway, making it a promising candidate for patients with HN.

Discovery of a Novel Thienopyrimidine Compound as a Urate Transporter 1 and Glucose Transporter 9 Dual Inhibitor with Improved Efficacy and Favorable Druggability.

Gout and hyperuricemia are metabolic diseases characterized with high serum uric acid (SUA) levels that significantly impact human health. Lesinurad, a uricosuric agent, is limited to concurrent use with xanthine oxidase inhibitors (XOIs) in clinical practice due to its restricted efficacy and potential nephrotoxicity. Herein, extensive structural modifications of lesinurad were conducted through scaffold hopping and substituent modification strategies, affording 54 novel derivatives containing pyrimidine-fused cyclic structures. Notably, the thienopyrimidine compound 29 demonstrated a remarkable 2-fold increase in SUA-lowering in vivo activity compared to lesinurad, while exhibiting potent inhibitory activity against the urate transporter 1 (URAT1, IC50 = 2.01 µM) and glucose transporter 9 (GLUT9, IC50 = 18.21 µM). Furthermore, it possessed a lower effective dosage of 0.5 mg/kg, favorable safety profile without any apparent acute toxicity at doses of 1000 mg/kg, and improved pharmacokinetic properties. Overall, we have discovered an efficacious URAT1/GLUT9 dual inhibitor for inhibiting urate reabsorption with favorable pharmacokinetic profiles.

Proline-derived quinoline formamide compounds as human urate transporter 1 inhibitors with potent uric acid-lowering activities.

We report the design and synthesis of a series of proline-derived quinoline formamide compounds as human urate transporter 1 (URAT1) inhibitors via a ligand-based pharmacophore approach. Structure-activity relationship studies reveal that the replacement of the carboxyl group on the polar fragment with trifluoromethanesulfonamide and substituent modification at the 6-position of the quinoline ring greatly improve URAT1 inhibitory activity compared with lesinurad. Compounds 21c, 21e, 24b, 24c, and 23a exhibit potent activities against URAT1 with IC50 values ranging from 0.052 to 0.56 µM. Furthermore, compound 23a displays improved selectivity towards organic anion transporter 1 (OAT1), good microsomal stability, low potential for genotoxicity and no inhibition of the hERG K+ channel. Compounds 21c and 23a, which have superior pharmacokinetic properties, also demonstrate significant uric acid-lowering activities in a mouse model of hyperuricemia. Notably, 21c also exhibits moderate anti-inflammatory activity related to the gout inflammatory pathway. Compounds 21c and 23a with superior druggability are potential candidates for the treatment of hyperuricemia and gout.

Protecting against ferroptosis in hyperuricemic nephropathy: The potential of ferrostatin-1 and its inhibitory effect on URAT1.

Hyperuricemic nephropathy (HN) is characterized by renal fibrosis and tubular necrosis caused by elevated uric acid levels. Ferroptosis, an iron-dependent type of cell death, has been implicated in the pathogenesis of kidney diseases. The objective of this study was to explore the role of ferroptosis in HN and the impact of a ferroptosis inhibitor, ferrostatin-1 (Fer-1). The study combined adenine and potassium oxonate administration to establish a HN model in mice and treated HK-2 cells with uric acid to simulate HN conditions. The effects of Fer-1 on the renal function, fibrosis, and ferroptosis-associated molecules were investigated in HN mice and HK-2 cells treated with uric acid. The HN mice presented with renal dysfunction characterized by elevated tissue iron levels and diminished antioxidant capacity. There was a significant decrease in the mRNA and protein expression levels of SLC7A11, GPX4, FTL-1 and FTH-1 in HN mice. Conversely, treatment with Fer-1 reduced serum uric acid, serum creatinine, and blood urea nitrogen, while increasing uric acid levels in urine. Fer-1 administration also ameliorated renal tubule dilatation and reduced renal collagen deposition. Additionally, Fer-1 also upregulated the expression levels of SLC7A11, GPX4, FTL-1, and FTH-1, decreased malondialdehyde and iron levels, and enhanced glutathione in vivo and in vitro. Furthermore, we first found that Fer-1 exhibited a dose-dependent inhibition of URAT1, with the IC50 value of 7.37 ± 0.66 µM. Collectively, the current study demonstrated that Fer-1 effectively mitigated HN by suppressing ferroptosis, highlighting the potential of targeting ferroptosis as a therapeutic strategy for HN.