Integrative analysis of transcriptomics and metabolomics reveals the protective effect and mechanism of salidroside on testicular ischemia-reperfusion injury.

Testicular torsion is a critical urologic condition for which testicular detorsion surgery is considered irreplaceable as well as the golden method of reversal. However, the surgical treatment is equivalent to a blood reperfusion process, and no specific drugs are available to treat blood reperfusion injuries. Salidroside (SAL) is one of the main effective substances in rhodiola, which has been shown to have antioxidant and antiapoptosis activities. This study was designed to determine whether SAL exerted a protective effect on testicular ischemia-reperfusion (I/R) injury. In this study, the I/R injury model of the testes and reoxygenation (OGD/R) model were used for verification, and SAL was administered at doses of 100 mg/kg and 0.05 mmol/L, respectively. After the experiments, the testicular tissue and TM4 Sertoli cells were collected for histopathologic and biochemical analyses. The results revealed that SAL improves the structure of testicular tissue and regulates the oxidation-antioxidation system. To further understand the molecular mechanisms of SAL in treating testicular I/R injuries, transcriptomics and metabonomics analyses were integrated. The results show that the Nfr2/HO-1/GPX4/ferroptosis signaling pathway is enriched significantly, indicating that it may be the main regulatory pathway for SAL in the treatment of testicular I/R injuries. Thereafter, transfection with Nrf2 plasmid-liposome was used to reverse verify that the Nfr2/HO-1/GPX4/ferroptosis signaling pathway was the main pathway for SAL anti-testicular I/R injury treatment. Thus, it is suggested that SAL can protect against testicular I/R injuries by regulating the Nfr2/HO-1/GPX4 signaling pathway to inhibit ferroptosis and that SAL may be a potential drug for the treatment of testicular I/R injuries.

Antidepressant Activity of Euparin: Involvement of Monoaminergic Neurotransmitters and SAT1/NMDAR2B/BDNF Signal Pathway.

Depression is the most significant risk factor for suicide, yet the causes are complex and disease mechanism remains unclear. The incidence and disability rate of depression are very high and the efficacy of some traditional antidepressants is not completely satisfactory. Recently, some studies have found that benzofurans have anti-oxidation and anti-monoamine oxidase properties, which are related to depression. Euparin is a monomer compound of benzofuran, previous work by our team found that it improves the behavior of depressed mice. However, additional antidepressant effects and mechanisms of Euparin have not been reported. In this study, the Chronic Unpredictable Mild Stress (CUMS) model of mice was used to further investigate the effect and mechanism of Euparin on depression. Results showed that Euparin (8, 16 and 32 mg/kg) reduced depression-like behavior in mice compared with the model group. Meanwhile, all doses of Euparin were found to increase the contents of monoamine neurotransmitter and decrease monoamine oxidase and reactive oxygen species (ROS) levels in brain of depression mice. Additionally, Euparin restored CUMS-induced decrease of Spermidine/Spermine N1-Acetyltransferase 1 (SAT1), N-methyl-D-aspartate receptor subtype 2B (NMDAR2B) and brain derived neurotrophic factor (BDNF) expression. These findings demonstrate that Euparin has antidepressant properties, and its mechanism involves the SAT1/NMDAR2B/BDNF signaling pathway.

Activation of M3 cholinoceptors attenuates vascular injury after ischaemia/reperfusion by inhibiting the Ca2+/calmodulin-dependent protein kinase II pathway.

BACKGROUND AND PURPOSE: The activation of M3 cholinoceptors (M3 receptors) by choline reduces cardiovascular risk, but it is unclear whether these receptors can regulate ischaemia/reperfusion (I/R)-induced vascular injury. Thus, the primary goal of the present study was to explore the effects of choline on the function of mesenteric arteries following I/R, with a major focus on Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) regulation. EXPERIMENTAL APPROACH: Rats were given choline (10 mg · kg(-1), i.v.) and then the superior mesenteric artery was occluded for 60 min (ischaemia), followed by 90 min of reperfusion. The M3 receptor antagonist, 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP), was injected (0.12 µg · kg(-1), i.v.) 5 min prior to choline treatment. Vascular function was examined in rings of mesenteric arteries isolated after the reperfusion procedure. Vascular superoxide anion production, CaMKII and the levels of Ca(2+)-cycling proteins were also assessed. KEY RESULTS: Choline treatment attenuated I/R-induced vascular dysfunction, blocked elevations in the levels of reactive oxygen species (ROS) and decreased the up-regulated expression of oxidised CaMKII and phosphorylated CaMKII. In addition, choline reversed the abnormal expression of Ca(2+)-cycling proteins, including Na(+)Ca(2+) exchanger, inositol 1,4,5-trisphosphate receptor, sarcoplasmic reticulum Ca(2+)-ATPase and phospholamban. All of these cholinergic effects of choline were abolished by 4-DAMP. CONCLUSIONS AND IMPLICATIONS: Our data suggest that inhibition of the ROS-mediated CaMKII pathway and modulation of Ca(2+)-cycling proteins may be novel mechanisms underlying choline-induced vascular protection. These results represent a significant addition to the understanding of the pharmacological roles of M3 receptors in the vasculature, providing a new therapeutic strategy for I/R-induced vascular injury.

Characterization of the molecular and electrophysiological properties of the T-type calcium channel in human myometrium.

Rises in intracellular calcium are essential for contraction of human myometrial smooth muscle (HMSM) and hence parturition. The T-type calcium channel may play a role in this process. The aim was to investigate the role of the T-type calcium channel in HMSM by characterizing mRNA expression, protein localization, electrophysiological properties and function of the channel subunits Cav3.1(alpha1G), Cav3.2(alpha1H), and Cav3.3(alpha1I). QRT-PCR, immunohistochemistry, electrophysiology and invitro contractility were performed on human myometrial samples from term, preterm, labour and not in labour. QRT-PCR analysis of Cav3.1, Cav3.2 and Cav3.3 demonstrated expression of Cav3.1 and Cav3.2 with no significant change (P>0.05) associated with gestation or labour status. Immunohistochemistry localized Cav3.1 to myometrial and vascular smooth muscle cells whilst Cav3.2 localized to vascular endothelial cells and invading leucocytes. Voltage clamp studies demonstrated a T-type current in 55% of cells. Nickel block of T-type current was voltage sensitive (IC50 of 118.57+/-68.9 microM at -30 mV). Activation and inactivation curves of ICa currents in cells expressing T-type channels overlapped demonstrating steady state window currents at the resting membrane potential of myometrium at term. Current clamp analysis demonstrated that hyperpolarizing pulses to a membrane potential greater than -80 mV elicited rebound calcium spikes that were blocked reversibly by 100 microM nickel. Contractility studies demonstrated a reversible decrease in contraction frequency during application of 100 microM nickel (P<0.05). We conclude that the primary T-type subunit expressed in some MSMCs is Cav3.1. We found that application of 100 microM nickel to spontaneously contracting human myometrium reversibly slows contraction frequency.

An electrophysiological study on the anti-ventricular arrhythmic effect of adenosine in the guinea pig.

Using whole-cell patch clamp technique this study investigated the effects of adenosine (Ado) on action potential, L-type calcium current (I(Ca.L)), delayed afterdepolarizations (DADs), and transient inward current (I(ti)) induced by isoproterenol (Iso) in guinea pig isolated single ventricular myocytes. The results showed: (1) Ado alone had no significant direct effects on action potential and I(Ca.L) in guinea pig ventricular myocytes at 20-100 micromol/L. However, Ado significantly attenuated the prolongation of action potential duration (APD) and the increase of the peak amplitude of I(Ca.L) induced by Iso. Iso (10 nmol/L) markedly increased APD(50) and APD(90) from 340+/-21 ms to 486+/-28 ms and from 361+/-17 ms to 501+/-29 ms, respectively (P<0.01), and increased the amplitude of I(Ca.L) from 6.53+/-1.4 pA/pF to 18.28+/-2.4 pA/pF (P<0.01). The peak potential of current-potential relationship shifted to the left. Ado (50 micromol/L) abbreviated APD(50), APD(90) to 403+/-19 ms and 419+/-26 ms (P<0.01), and decreased the peak amplitude of I(Ca.L) to 10.2+/-1.5 pA/pF (P<0.01 vs Iso), but did not change resting membrane potential (RMP), action potential amplitude (APA), and overshoot (OS). (2) Iso (30 nmol/L) reproducibly elicited DADs with 100% incidence of DADs under this condition. Ado (50 micromol/L) completely inhibited Iso from inducing DADs. Iso (30 nmol/L) elicited I(ti) with 2-second depolarizing voltage-clamp pulses rising to +20 mV from a holding potential of -40 mV, the incidence of I(ti) being 100%, and the I(ti) was suppressed in the presence of Ado (50 micromol/L) with the incidence of I(ti) decreased to 14.3% (P<0.05). These data indicate that Ado antagonizes the stimulatory effect of Iso, and that the antiarrhythmic mechanism of Ado preventing Iso-induced DADs is due to the inhibition of intracellular Ca(2+) overload through attenuating the prolongation of APD, the enhance of I(Ca.L) and I(ti).