Pharmacology最新文献

Introduction: The exosomes from adipose-derived mesenchymal stem cells (AMSCs) had therapeutic effects. However, whether the exosomes derived from hypoxia-treated AMSCs could improve renal functions in unilateral ureteral obstruction (UUO) mice remains unclear.

Methods: The exosomes were characterized using a transmission electron microscope and Western blot. Its size distribution was determined using the Zetasizer Nano ZS analysis system. The differentiation ability was assessed by alkaline phosphatase and oil red staining. Consequently, the function of exosomes in inhibiting inflammatory factors was evaluated using an enzyme-linked immunosorbent assay, and apoptosis inhibition was evaluated by Western blot. Finally, the function of exosomes to ameliorate kidney fibrosis using qPCR, Western blot, hematoxylin-eosin staining and Masson staining.

Results: The cultured AMSCs could differentiate into osteoblast and adipocyte. Meanwhile, the cultured AMSCs could effectively secrete the exosomes, which were characterized with around 110 nm diameter and surface marker expression. Exosomes derived from hypoxia-treated AMSCs improved renal functions in UUO mice. The mechanism exploration revealed that exosomes could decrease the TNF-α and IL-6 and inhibit cell apoptosis. Finally, the fibrosis-associated protein was reversed, and the renal dysfunctions were ameliorated in UUO mice.

Conclusion: The exosomes derived from the hypoxia-treated AMSCs have a better effect than those from normal AMSCs in ameliorating renal dysfunctions in UUO mice.

Introduction: Eleclazine is a highly selective late sodium current inhibitor, possibly effective in reducing ventricular fibrillation (VF) in heart failure (HF) with ischemia-reperfusion (IR) injury. The electrophysiological effects of eleclazine at therapeutic hypothermia (TH) are unknown. We investigated the effects of eleclazine in suppressing VF in failing rabbit hearts with IR injury undergoing TH.

Method: HF was induced by right ventricular pacing. An IR model was created using coronary artery ligation for 60 min, followed by reperfusion for 30 min. Hearts were excised and Langendorff-perfused for optical mapping and electrophysiological studies. Electrophysiological studies were repeated after TH (33 oC) for 30 min or eleclazine (1 μM) infusion for 20 min.

Results: In failing IR-injured hearts, eleclazine reduced action potential duration (APD) dispersion and accelerated intracellular Ca2+ uptake to suppress arrhythmogenic alternans, but also exacerbated rate-dependent conduction slowing, resulting in neutral effects on VF inducibility at normothermia. TH increased VF severity. Eleclazine after TH ameliorated TH-induced APD dispersion and further depressed conduction to reduce VF inducibility and severity. TH after eleclazine also slowed conduction to a greater extent to reduce VF inducibility and severity by extrastimulus pacing. In control IR-injured hearts, eleclazine increased VF severity by dynamic pacing at normothermia, which was counteracted by TH.

Conclusions: Eleclazine does not prevent VF at normothermia, but reduces VF inducibility and severity by extrastimulus pacing at TH in isolated failing hearts with regional IR injury.

Introduction: Diabetes mellitus is known to provoke devastating anomalies in myocardial structure and function, while effective therapeutic regimen is still lacking. The selective protease inhibitor UCF101 (5-[5-(2-nitrophenyl) furfuryl iodine]-1,3-diphenyl-2-thiobarbituric acid) has been shown to fend off ischemic heart injury, although its impact on diabetic cardiomyopathy remains elusive.

Methods: Our present work was conducted to examine the effect of UCF101 on experimental diabetes-evoked cardiac geometric and functional abnormalities as well as mechanisms involved. Adult mice were made diabetic using streptozotocin (STZ, 50 mg/kg, i.p., for 5 days) while receiving UCF101 (7.15 mg/kg, i.p.).

Results: STZ evoked cardiac hypertrophy, interstitial fibrosis, mitochondrial ultrastructural damage, oxidative stress, dampened autophagy (LC3B, Beclin 1, elevated p62), mitophagy (FUNDC1 and Parkin with upregulated TOM20), increased left ventricular end systolic diameter, reduced fractional shortening, ejection fraction, cardiomyocyte shortening capacity, velocities of shortening/re-lengthening, and rise in intracellular Ca2+ in conjunction with elongated diastole and intracellular Ca2+ removal, the responses were overtly reconciled by UCF101 with little effects from UCF101 itself. Levels of cell injury markers Omi/HtrA2, TNFα, and stress signaling (JNK, ERK, p38) were overtly enhanced along with compromised phosphorylation of cellular fuel AMP-activated protein kinase (AMPK) (Thr172) and cell survival molecule GSK3β, as well as downregulated SERCA2a and elevated phospholamban, the effect was reversed by UCF101 (except for SERCA2a). AMPK knockout, pharmacological inhibition, the mitophagy inhibitor liensinine, and parkin knockout nullified UCF101-offered cardioprotection in diabetes. UCF101 reversed STZ-induced upregulation in the AMPK degrading enzymes PP2A and PP2C.

Conclusion: These findings suggest that UCF101 rescues diabetes-mediated alterations in cardiac structure and function, likely through AMPK-mediated regulation of mitophagy.

Introduction: Melanocyte ferroptosis has been proven to contribute to the development of vitiligo. Tanshinone IIA (TSA), a Chinese herbal extract, has been shown to inhibit vitiligo progression. Whether TSA regulates ferroptosis in melanocytes remains unclear.

Methods: Hydrogen peroxide (H2O2) was used to induce melanocytes to stimulate vitiligo cell model in vitro. Cell proliferation was examined by 5-ethynyl-2'-deoxyuridine assay. The levels of malondialdehyde, reactive oxygen species, glutathione peroxidase, and iron were detected by corresponding commercial kit. The protein levels of ferroptosis-related markers and Nrf2 pathway-related markers were examined using western blot and immunofluorescence staining. Cell viability and cytotoxicity were analyzed using Cell Counting Kit-8 assay and lactate dehydrogenase detection. Mitochondrial morphology was examined using a transmission electron microscope.

Results: After H2O2 treatment, melanocyte proliferation was reduced, while oxidative stress and ferroptosis were enhanced. TSA treatment could inhibit ferroptosis in H2O2-induced melanocytes. Besides, TSA could activate Nrf2 pathway and promote Nrf2 nuclear translocation, and Nrf2-specific inhibitor (ML385) also reversed the inhibitory effect of TSA on H2O2-induced melanocyte ferroptosis.

Conclusion: Our data showed that TSA alleviated H2O2-induced melanocyte ferroptosis via activating Nrf2 pathway.

Introduction: Hypertension is prevalent in older women and men, but the impact of sex differences is unclear.

Methods: Blood pressure (BP) was evaluated weekly for 15 weeks using tail-cuff plethysmography in intact or gonadectomized female and male rats. Similarly, gonadectomized rats were subcutaneously treated daily for 15 weeks with estradiol in females or testosterone in males. Treatment with estrogen in males and androgen in females for BP was also examined. The non-genomic antihypertensive potency and efficacy of different sex steroids were determined; catheters were implanted in the carotid artery of hypertensive rats for BP recording with bolus injections in the jugular vein at cumulative doses (1 × 10-7-1 × 10-4M kg-1 min-1) of dehydroepiandrosterone (DHEA), estradiol, testosterone, or 5β-dihydrotestosterone (5β-DHT).

Results: Data showed a time-dependent increase in BP after gonadectomy in female and male rats until hypertension values were reached. Males are more sensitive to the development of hypertension than females. The increases in BP in females and males were completely prevented by estradiol or testosterone, respectively. Testosterone completely prevented hypertension in females, whereas estradiol only partially in males. Antihypertensive potencies in conscious hypertensive rats were DHEA = 5β-DHT = testosterone >> estradiol, in females and DHEA = 5β-DHT >> testosterone >> estradiol in males. The efficacy was DHEA = 5β-DHT = testosterone >> estradiol in females and 5β-DHT = DHEA >> testosterone >> estradiol in males.

Conclusion: Gonadectomized males developed hypertension faster than females, suggesting that androgen deficiency plays an important role in BP reduction. Antihypertensive responses of steroids are structure-dependent; estradiol demonstrated the lowest potency, whereas 5β-DHT was a potent antihypertensive without estrogenic and androgenic actions, suggesting it is as a therapeutic candidate for controlling hypertension in both sexes.

Background: Pulmonary artery hypertension (PAH) is a severe cardiovascular disease marked by a persistent increase in pulmonary artery resistance and pressure, leading to right ventricular strain, hypertrophy, and eventually right heart failure and death. Despite numerous available targeted therapies, the clinical needs for treating PAH remain unmet. Current treatments primarily aim to dilate pulmonary vessels rather than reverse pulmonary vascular remodeling, failing to offer a fundamental solution for PAH. Therefore, developing new therapies for this condition is urgently required.

Summary: Recent research has highlighted the crucial role of non-coding RNAs (ncRNAs) in the occurrence and development of PAH. NcRNAs, such as long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), microRNAs (miRNAs), and PIWI-interacting RNAs (piRNAs), are a class of transcripts that do not translate proteins but affect various diseases at different levels, including chromatin modification, transcription regulation, post-translational processes.

Key message: The current study delves into recent advancements in understanding how lncRNAs, circRNAs, miRNAs, and piRNAs contribute to the pathogenesis of PAH. This review addresses the existing research challenges and explores the potential of ncRNAs as both biomarkers and therapeutic targets, suggesting that ncRNAs may serve as valuable indicators and treatment options for the disease.

Introduction: Citrus juice has been shown to cause QT prolongation in electrocardiograms of healthy volunteers, and naringenin, a major flavonoid found in citrus juice, has been identified as the potent inhibitor of human ether-a-go-go-related gene (HERG) channels as the cause of QT prolongation. Inhibition of HERG channels and prolongation of QT interval by antipsychotic drugs such as haloperidol, chlorpromazine, and clozapine have also been shown. However, naringenin's effect on HERG channel function in conjunction with antipsychotic medications has not been investigated.

Methods: In the present study, we evaluated the effect of combining naringenin with antipsychotics on the function of HERG channels expressed in Xenopus oocytes.

Results: When 30 µm naringenin was added to antipsychotic drugs (1 µm haloperidol, 10 µm chlorpromazine, or 10 µm clozapine), significantly greater HERG inhibition was demonstrated, compared to the inhibition caused by antipsychotic drugs alone. Co-application studies also showed that the magnitudes of inhibitions caused by naringenin + antipsychotics were similar to that predicted by the allotopic interaction model, suggesting that naringenin and antipsychotics bind to the HERG channel at different sites.

Conclusion: The results suggest that there is an additive interaction between antipsychotics and naringenin. Due to the potential for repolarization heterogeneity and a decrease in repolarization reserve, this additive HERG inhibition may increase the risk of arrhythmias.