Excess heme upregulates heme oxygenase 1 and promotes cardiac ferroptosis in mice with sickle cell disease.

Sickle cell disease (SCD) is characterized by increased hemolysis, which results in plasma heme overload and ultimately cardiovascular complications. Here, we hypothesized that increased heme in SCD causes upregulation of heme oxygenase 1 (Hmox1), which consequently drives cardiomyopathy through ferroptosis, an iron-dependent non-apoptotic form of cell death. First, we demonstrated that the Townes SCD mice had higher levels of hemopexin-free heme in the serum and increased cardiomyopathy, which was corrected by hemopexin supplementation. Cardiomyopathy in SCD mice was associated with upregulation of cardiac Hmox1, and inhibition or induction of Hmox1 improved or worsened cardiac damage, respectively. Because free iron, a product of heme degradation through Hmox1, has been implicated in toxicities including ferroptosis, we evaluated the downstream effects of elevated heme in SCD. Consistent with Hmox1 upregulation and iron overload, levels of lipid peroxidation and ferroptotic markers increased in SCD mice, which were corrected by hemopexin administration. Moreover, ferroptosis inhibitors decreased cardiomyopathy, whereas a ferroptosis inducer erastin exacerbated cardiac damage in SCD and induced cardiac ferroptosis in nonsickling mice. Finally, inhibition or induction of Hmox1 decreased or increased cardiac ferroptosis in SCD mice, respectively. Together, our results identify ferroptosis as a key mechanism of cardiomyopathy in SCD.

Prescription patterns of herbal medicine for menopausal disorders in major Korean medicine hospitals: a multicenter retrospective study.

BACKGROUND: This study aimed to obtain the symptom, prescription and therapeutic patterns for the treatment of patients with menopausal syndrome in major Korean medicine (KM) hospitals. METHODS: We used a retrospective chart review of climacteric disorder and postmenopausal syndrome patients by examining medical records (ICD-10, menopausal and female climacteric states: N95.1, Menopausal and perimenopausal disorder, unspecified: N95.9) from eight university KM hospitals in South Korea. RESULTS: The main symptoms of 1,682 patients with menopausal disorders visiting eight college-affiliated oriental medicine hospitals were hot flush, hyperhidrosis, fatigue, insomnia, and chest tightness. Guipi decoction, Si-wu guipi decoction, Qing-xin lianzi-yin, Jiawei xiao-yao-san and Guipi wen-dan decoction were the most commonly prescribed treatments for menopausal disorders. Patients were most often treated with a combination of herbal medicine and acupuncture. CONCLUSION: Our study shows that the current prescribed herbal medicines were used for treating menopausal disorders in Korean medicine hospitals. However, the objectivity of the efficacy assessment should be studied further.

Pharmacokinetic Profile of Kaurenoic Acid after Oral Administration of Araliae Continentalis Radix Extract Powder to Humans.

The objective of this study was to characterize pharmacokinetics (PKs) of kaurenoic acid (KAU) after administration of the clinical usual dose of Araliae Continentalis Radix extract powder to Korean subjects for the first time and evaluate the mechanism of its absorption in vitro. A simple, sensitive, and selective analytical method was developed for the detection of KAU in human plasma. Concentrations of KAU were quantified by ultra-performance liquid chromatography tandem mass spectrometry after simple liquid⁻liquid extraction. This pharmacokinetic model of KAU was best described by a two-compartment model with first-order absorption. To identify efflux transporters involved in the absorption of KAU, a Caco-2 monolayer model was used. Estimated PK parameters were: systemic clearance, 23.89 L/h; inter-compartmental clearance, 15.55 L/h; rate constant for absorption, 1.72 h-1; volume of distribution of the central compartment, 24.44 L; and volume of distribution of the peripheral compartment, 64.05 L. Results from Caco-2 bidirectional transport study suggested that KAU was a potential substrate of efflux transporters. In summary, PKs of KAU were successfully characterized after administration of a usual dose of Araliae continentalis Radix extract powder in human with the newly developed bioanalytical method and the mechanism of absorption of KAU was identified clearly.

Simultaneous UPLC-MS/MS determination of four components of Socheongryong-tang tablet in human plasma: Application to pharmacokinetic study.

The purpose of this study was to develop a method for simultaneous analysis of schizandrin, ephedrine, paeoniflorin, and cinnamic acid as constituents of Socheongryong-tang tablet in human plasma using UPLC-MS/MS. These four components were separated using water containing 0.01% formic acid and methanol as a mobile phase by gradient elution at a flow rate of 0.3 mL/min with a HALO-C18 column (2.1 mm × 100 mm, 2.7 µm particle size). Quantitation was performed on a triple quadrupole mass spectrometer employing electrospray ionization technique operated in multiple reaction monitoring mode. Mass transitions were m/z 432.9 → 384.1 for schizandrin, 165.8 → 148.1 for ephedrine, 525.0 → 449.2 for paeoniflorin, 146.8 → 102.9 for cinnamic acid, and 340.0 → 324.0 for papaverine as internal standard. Liquid-liquid extraction and protein precipitation with ethyl acetate-methanol (1:2, v/v) were used to obtain these four components. Chromatograms showed high resolution, sensitivity, and selectivity without interference by plasma constituents. Calibration curves of schizandrin, ephedrine, paeoniflorin, and cinnamic acid in human plasma ranged from 0.02 to 8 ng/mL, 0.5 to 200 ng/mL, 0.2 to 80 ng/mL, and 1 to 400 ng/mL, respectively. Calibration curves of each analyte displayed excellent linearity, with correlation coefficients > 0.99. For all four components, both intra- and inter-day precisions (CV%) were <5.99%. The accuracy was 99.35-103.30% for schizandrin, 98.48-104.38% for ephedrine, 97.06-103.34% for paeoniflorin, and 99.97-104.36% for cinnamic acid. This analytical method developed in this study satisfied the criteria of international guidance. It could be successfully applied to pharmacokinetic studies of schizandrin, ephedrine, paeoniflorin, and cinnamic acid after oral administration of Socheongryong-tang tablet to humans.