N-Cinnamoylpyrrole-derived alkaloids from the genus Piper as promising agents for ischemic stroke by targeting eEF1A1.

BACKGROUND: Ischemic stroke (IS) is a serious cerebrovascular disease characterized by significantly elevated mortality and disability rates, and the treatments available for this disease are limited. Neuroinflammation and oxidative stress are deemed the major causes of cerebral ischemic injury. N-Cinnamoylpyrrole alkaloids form a small group of natural products from the genus Piper and have not been extensively analyzed pharmacologically. Thus, identifying the effect and mechanism of N-cinnamoylpyrrole-derived alkaloids on IS is worthwhile. PURPOSE: The present research aimed to explore the antineuroinflammatory and antioxidative stress effects of N-cinnamoylpyrrole-derived alkaloids isolated from the genus Piper and to explain the effects and mechanism on IS. METHODS: N-cinnamoylpyrrole-derived alkaloids were isolated from Piper boehmeriaefolium var. tonkinense and Piper sarmentosum and identified by various chromatographic methods. Lipopolysaccharide (LPS)-induced BV-2 microglia and a mouse model intracerebroventricularly injected with LPS were used to evaluate the antineuroinflammatory and antioxidative stress effects. Oxygen‒glucose deprivation/reperfusion (OGD/R) and transient middle cerebral artery occlusion (tMCAO) models were used to evaluate the effect of PB-1 on IS. To elucidate the fundamental mechanism, the functional target of PB-1 was identified by affinity-based protein profiling (ABPP) strategy and verified by cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS), and circular dichroism (CD) analyses. The effect of PB-1 on the NF-κB and NRF2 signaling pathways was subsequently evaluated via western blotting and immunofluorescence staining. RESULTS: The results showed that N-cinnamoylpyrrole-derived alkaloids significantly affected neuroinflammation and oxidative stress. The representative compound, PB-1 not only inhibited neuroinflammation and oxidative stress induced by LPS or OGD/R insult, but also alleviated cerebral ischemic injury induced by tMCAO. Further molecular mechanism research found that PB-1 promoted antineuroinflammatory and antioxidative stress activities via the NF-κB and NRF2 signaling pathways by targeting eEF1A1. CONCLUSION: Our research initially unveiled that the therapeutic impact of PB-1 on cerebral ischemic injury might rely on its ability to target eEF1A1, leading to antineuroinflammatory and antioxidative stress effects. The novel discovery highlights eEF1A1 as a potential target for IS treatment and shows that PB-1, as a lead compound that targets eEF1A1, may be a promising therapeutic agent for IS.

Three new phenolic glycosides and a new lignan glycoside from Gaultheria leucocarpa var. yunnanensis.

Three new phenolic glycosides (1-3) and a new lignan glycoside (4), together with five known compounds (5-9) were isolated from the ethanol extract of the aerial part of Gaultheria leucocarpa var. yunnanensis (Franch.) T.Z.Hsu & R.C.Fang. Their structures were determined on the basis of spectroscopic techniques, experimental and calculated ECD spectra, acid hydrolysis, and enzymatic hydrolysis experiments. All the isolates were evaluated for their anti-inflammatory and antioxidant activities. Compounds 7 and 8 exhibited inhibitory effects against the LPS-induced production of NO with IC50 of 63.71 and 10.66 µM, respectively, compared to L-NMMA having an IC50 of 6.95 µM. Besides, compound 7 also represented significant DPPH radical scavenging activity with EC50 of 18.75 µM, comparable with vitamin C (EC50 = 15.77 µM).

Flavonol glycosides and phenylpropanoid glycosides with inhibitory effects on microglial nitric oxide production from Neoshirakia japonica.

Five new flavonol glycosides (1-5), one new phenylpropanoid glycoside (6), and nine known glycosides (7-15) were isolated from the stems and leaves of Neoshirakia japonica. The structures of the new compounds were determined by detailed analysis of spectroscopic data (HRESIMS, 1D and 2D NMR) and acid hydrolysis experiment. The antineuroinflammatory effects of all the isolates were evaluated by inhibiting NO production against LPS-induced BV-2 microglial cells. Compounds 1, 8, and 9 showed more potent inhibitory activities with IC50 values of 2.7, 5.5, and 4.1 µM, respectively, than that of the positive control minocycline (IC50 = 15.6 µM), while compounds 7 (IC50 = 17.0 µM) and 10 (IC50 = 24.3 µM) also displayed inhibitory activities to a certain degree.

Network Pharmacology-Based Strategy for Predicting Active Ingredients and Potential Targets of Gegen Qinlian Decoction for Rotavirus Enteritis.

MATERIALS AND METHODS: In this study, a network pharmacology-based strategy was used to elucidate the mechanism of GGQLD for the treatment of RVE. Oral bioavailability and drug-likeness were taken as the judgment criteria to search the active ingredients of GGQLD in traditional Chinese medicine systems pharmacology database and analysis platform (TCMSP). The affinity between protein and ingredients was further determined using the similarity ensemble approach to find the corresponding targets. According to the genes related to enteritis in GeneCards database, the key targets were screened by intersections between drug and disease targets. And the therapeutic mechanism was predicted using the protein-protein interactions (PPIs), the Gene Ontology (GO), and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, which was verified by detecting calcium ion concentration with the fluorescent probe. RESULT: 130 active ingredients were screened from GGQLD, including (R)-canadine, moupinamide, formononetin, and other flavonoids. They act on a total of 366 targets, which is mainly distributed in the biological process of hormone binding or signaling pathways of neuroactive ligand receptor interaction, serotonergic synapse, and calcium signaling pathway. Furthermore, serotonin receptors, adrenergic receptors, cholinergic receptors, and dopamine receptors in the enteric nervous system may be the key targets of RVE treatment by GGQLD. CONCLUSION: This study demonstrated that the potential mechanism that GGQLD can effectively improve the symptoms of RVE may depend on the regulation of calcium ions, serotonin, and gastrointestinal hormone ion that could mutually affect the intestinal nervous system.

Electrical stimulation of deep peroneal nerve mimicking acupuncture inhibits the pressor response via capsaicin-insensitive afferents in anesthetized rats.

OBJECTIVE: To assess the inhibitory modulation of blood pressure by stimulation of the deep peroneal nerve (DPN) and to determine the involvement of nociceptive fibers in the modulation. METHODS: All the animals were divided into six groups (A-F). The rats in groups A and B received no pretreatment. The rats in groups C and D received subcutaneous injection of capsaicin or control vehicle, respectively, near the DPN for 2 days. Those in groups E and F had the DPN exposed to capsaicin or control vehicle, respectively, for 20 min. Subsequently, pressor responses were induced by stimulation of paraventricular nucleus (PVN) either electrically (groups A and C C-F) or chemically via injection of glutamate (group B). After two stable pressor responses (baseline), all groups were subject to 5-min DPN stimulation followed by PVN stimulation for 10 s. Arterial blood pressure, heart rate, and electrocardiogram were recorded. The pressor response was calculated as the difference in the mean arterial pressure (MAP) before and after PVN stimulation, and changes from baseline in pressor response after DPN stimulation were compared between the groups. RESULTS: Increases of MAP of 22.88±2.18 mm Hg and 20.32±5.25 mm Hg were induced by electrical (group A) or chemical (group B) stimulation of the PVN, respectively. These pressor responses were inhibited by stimulation of the DPN, and the MAP was reduced to 12.00±2.10 mm Hg in group A (n=6, P<0.01) and 7.00±2.85 mm Hg in group B (n=6, P<0.01). Subcutaneous injection of capsaicin (125 mg/kg) near the DPN in group C (n=7) had no effect on the inhibitory effect of DPN stimulation compared with the group D (n=9), and neither did blockade of nociceptive fibers with capsaicin in group E (n=6) compared with group F (n=8). CONCLUSION: Stimulation of the DPN mimicking acupuncture has an inhibitory effect on the pressor response, and the effect is mediated by capsaicin-insensitive afferent fibers in the DPN.

[Effects of oxymatrine on microinflammatory state in patients undergoing continuous hemodialysis: a randomized controlled trial].

BACKGROUND: Chronic microinflammatory state is common in the patients undergoing maintenance hemodialysis (MHD), which seriously affects the long-term survival rate of MHD patients. It is important to improve the microinflammatory state in MHD patients. OBJECTIVE: To investigate the effects of oxymatrine on microinflammatory state in patients undergoing continuous hemodialysis. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: Sixty MHD patients in Blood Purification Center, Wuhan No.1 Hospital, from June to September 2008, were randomized into treatment group (30 cases) and control group (30 cases). Oxymatrine Capsule was orally administered to the patients in the treatment group 0.4 g once a day for 3 months, while the patients in the control group were not given oxymatrine. MAIN OUTCOME MEASURES: The serum concentrations of high-sensitivity C-reactive protein (hs-CRP), interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), albumin (Alb), pre-albumin (PAB), total cholesterol (TC) and triglyceride (TG) were detected before and after 3-month treatment. RESULTS: Three patients in the treatment group had a stomachache on the first day of treatment, and two out of the three quitted the trial. The stomachache disappeared in one patient after stopping taking the drug, and did not recur after continuing to receive the intervention. Two patients in the treatment group had skin rash with pruritus on the second day of treatment. The rash disappeared after the patients stopped taking the drug, and did not recur after continuing to receive the intervention. A total of 58 cases accessed to the statistical analysis, while 2 cases were excluded. In the treatment group, the concentrations of hs-CRP, IL-1beta and TNF-alpha significantly decreased (P<0.01) and the mean values of Alb, PAB, TC and TG significantly increased after the treatment as compared with those before the treatment (P<0.01), but there were no significant differences in all parameters between before and after treatment in the control group. There were significant differences in all parameters between the treatment group and the control group after treatment (P<0.01, P<0.05). CONCLUSION: Oxymatrine can improve the microinflammatory state in the patients undergoing continuous hemodialysis.