Basic & Clinical Pharmacology & Toxicology最新文献

Renal fibrosis is closely related to the prognosis of chronic kidney disease (CKD). The increase in cGMP reduces renal fibrosis. Soluble guanylate cyclase (sGC) and phosphodiesterase (PDE) are key enzymes that maintain cGMP levels. BAY 41–8543 (1 mg/kg/day) and/or BAY 73–6691 (1 mg/kg/day) were used to treat 5/6 nephrectomized rats for 13 weeks. 5/6 Nephrectomy caused an increase in cystatin C, proteinuria and glomerulosclerosis and renal interstitial fibrosis. Neither sGC stimulation nor PDE9 inhibition alone improved kidney function and morphology, whereas BAY 41–8543 in combination with BAY 73–6691 attenuated renal interstitial fibrosis. This beneficial effect could not be explained by alterations in blood pressure and the renal immune system. BAY 41–8543 in combination with BAY 73–6691 had no effect on renal macrophage, CD4 + T-cell and CD8 + T-cell in the late-stage of 5/6 nephrectomy. RNA sequencing revealed BAY 41–8543 in combination with BAY 73–6691 down-regulated the expression of fibrosis-related genes such as Collagen Type I Alpha 1, Collagen Type III Alpha 1 Chain and Collagen Type XIV Alpha 1 Chain. sGC stimulator combined with PDE9 inhibitor attenuated renal fibrosis in 5/6 nephrectomized rats by down-regulating fibrosis-related gene expression. This novel approach of using low-dose combination therapies to minimize side effects while maintaining therapeutic efficacy offers a promising strategy for the treatment of CKD.

Obesity-induced impairment of myogenic differentiation leads to muscle loss and sarcopenia. Pyruvate dehydrogenase (PDH) plays a crucial role in glucose metabolism and is associated with muscle differentiation. However, the effect of dichloroacetate (DCA), a PDH activator, on obesity-induced impairment of myogenic differentiation remains unknown. Here, we evaluated the effects of DCA treatment on high-fat intake-induced impairment of myogenic differentiation in C2C12 cells and C57BL/6 mice. In C2C12 cells, DCA treatment improved PDH activity that was reduced by palmitate (PAL) and decreased the lactate concentrations in the media. Additionally, DCA reversed PAL- and high-fat diet (HFD)-induced decrease in the expression of myoblast determination protein 1 (MyoD), myogenin (MyoG) and myosin heavy chain (MyHC) in C2C12 cells and C57BL/6 mice. To explore the possible mechanism, DCA treatment restored the levels of p-Akt, p-FoxO1, p-FoxO3a and p-p38 MAPK levels in PAL-treated C2C12 cells. Moreover, the protective effects of DCA were reversed by treatment with the Akt inhibitor MK2206 in C2C12 cells. In summary, DCA treatment alleviated high-fat intake-induced impairment of myogenic differentiation via Akt signalling, suggesting its potential in treating obesity-associated muscle loss and sarcopenia.

Cetirizine is an antihistamine commonly used to treat allergic rhinitis and other allergic conditions. Cetirizine is often prescribed to breastfeeding mothers although there is limited information on infant exposure via breast milk. The aim of this study was to develop a popPK model based on data from a lactation study to predict cetirizine breast milk concentrations and estimate the relative infant dose (RID) in a breastfed infant. A popPK model was developed in NONMEM on data from a human lactation study including 35 women using cetirizine or levocetirizine while breastfeeding. Serial samples of breast milk were collected (n = 205) and the cetirizine concentrations quantified using a validated LC–MS/MS method. A one-compartment model of cetirizine in breast milk was developed and employed to calculate the relative infant dose (RID). Covariates related to the maternal characteristics and breastfeeding patterns were evaluated in the model; only milk sampling pumping duration was found to be a significant covariate, with an increasing pumping duration leading to an increased apparent milk volume of distribution (V_m). The mean RID was 1.99% with the highest RID being 3.36% at C_max. PopPK modelling could be used to estimate infant exposure to cetirizine via breast milk. The low predicted exposure in infants supports that cetirizine is compatible with breastfeeding.

Most central nervous system (CNS) active drugs are organic cations, which need carrier proteins for efficient transfer through the blood–brain barrier (BBB). A genetically still unidentified proton organic cation (H⁺/OC) antiporter is found in several tissues, including endothelial cells of the BBB. We characterized the substrate spectrum of the H⁺/OC antiporter and the overlap in substrate spectrum with OCTN1, OCTN2 or OCT3 by screening 87 potential substrates for transport activity. Based on high antiport rates, 45 of the tested substances were substrates of the H⁺/OC antiporter. They included antidepressants (like tranylcypromine or nortriptyline), antipsychotics (like levomepromazine) and local anaesthetics. Concentration-dependent transport was confirmed for 38 of the substrates. Transport uptake depending on a pH gradient across the cell membrane confirmed that 43 drugs were indeed substrates of the H⁺/OC antiporter. However, the patterns of pH dependence differed between the substrates, possibly indicating different modes of transport or the existence of multiple antiporter proteins. The substrate overlap between the H⁺/OC antiporter and OCTN1, OCTN2 or OCT3 was minimal, indicating that the latter three are not the proteins underlying the H⁺/OC antiporter activity. Overall, about 50% of positively charged drugs may be substrates of the antiporter, which may be the most important membrane transport protein for many drugs.

Chronic inflammation significantly contributes to the progression of osteoarthritis (OA), and an anti-inflammatory small molecule derived from medicinal herbs could be a potential drug candidate for OA. Herein, we investigated the function and mechanism of Evodiamine (EAE), the active ingredient from Evodia rutaecarpa, in chondrocytes and macrophages in vitro and in vivo. The cytotoxicity of EAE was determined using an MTT assay. And the anti-inflammatory and anti-extracellular matrix (ECM) degradation effects of EAE were investigated using qRT-PCR, western blot (WB), immunofluorescence (IF). Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), Fluo-4 AM, IF and AutoDock were used to elucidate the molecular mechanisms and signalling pathways of the reducing-inflammatory properties of EAE on chondrocytes in vitro. Moreover, the effect of EAE on macrophage polarization was detected by IF and flow cytometry (FC). Ultimately, we explored the in vivo therapeutic efficacy of EAE in an anterior cruciate ligament transection (ACLT)-induced OA model. The finding demonstrated that EAE blocked the phosphorylation of IKBα and Ca²⁺ influx, thereby curbing inflammation and ECM degradation. Additionally, EAE can prevent the polarization towards the M1 phenotype. Thus, our findings suggest that EAE has great potential as a therapeutic drug for the treatment of OA.

HSK21542 injection is a new peripheral kappa opioid receptor (KOR) agonist. To evaluate its safety, tolerability, pharmacokinetics and pharmacodynamics, this study was conducted in healthy volunteers, consisting of two parts: a single ascending dose (0.2–3.375 μg/kg, 15-min infusion) and different infusion durations (0.2 and 1 μg/kg, 2- or 15-min infusion). The area under the plasma concentration-time curve (AUC) and peak concentration (C_max) of HSK21542 were dose-linear among 0.2–3.375 μg/kg. After intravenous injection, HSK21542 was rapidly eliminated with a half-life (t_1/2) of 1.5 h, and the majority (48.02%) of the dose was excreted unchanged in urine. Pharmacodynamic results showed that HSK21542 increased prolactin release and reached a peak at 1–2 h after administration but had no significant effect on vasopressin levels. There was a brief increase in urine volume within the initial 2 h after administration. HSK21542 was well tolerated; most of the adverse effects (AEs) in the trial group were grade 1, and only 2 cases (4.0%) were grade 2. The main AE was paresthesia, which appeared in 42% (21/50) in the trial group. No serious adverse event (SAE) was observed. No subject withdrew early due to AEs. These results suggest that HSK21542 may be a potential treatment for pain and pruritic conditions.