Sedative-hypnotic effects of Boropinol-B on mice via activation of GABAA receptors.

OBJECTIVES: Boropinol-B is a phenylpropanoid compound originally isolated from Boronia pinnata Sm. (Rutaceae). This study aimed to evaluate the sedative-hypnotic effects of Boropinol-B and explore the underlying mechanisms. METHODS: Pentobarbital sodium-induced sleep mouse model and caffeine-induced insomnia mouse model were used to investigate the sedative effects of Boropinol-B. Pharmacokinetics profiles of Boropinol-B in rats were evaluated by high-performance liquid chromatography. The effects of Boropinol-B on the γ-aminobutyric acid (GABA)ergic system were investigated using ELISA assay and patch-clamp technique. Immunohistochemistry and immunofluorescence were carried out to assess the effects of Boropinol-B on sleep-related brain nucleus. KEY FINDINGS: Boropinol-B showed significant sedative effects, including reduced sleep latency, increased sleep duration in pentobarbital sodium-treated mice and decreased locomotor activity in insomnia mice. Pharmacokinetics studies demonstrated that Boropinol-B had a rapid onset of action, a short half-life and no accumulation. It increased the GABA level in mice's brain, and promoted chloride ions influx mediated by the γ-aminobutyric acid type A (GABAA) receptors in neurons. Also, it increased the c-Fos positive ratio of GABAergic neurons in ventrolateral preoptic nucleus and decreased c-Fos expression in tuberomammillary nucleus. CONCLUSION: Boropinol-B showed significant sedative-hypnotic effects in mice by activating the GABAA receptors and stimulating the sleep-related brain nucleus.

Co-Delivery of Daunorubicin and Homoharringtonine in Folic Acid Modified-Liposomes for Enhancing Therapeutic Effect on Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) remains a threatening disease due to severe complications, drug resistance, and high recurrence rates. Many drug combinations have demonstrated enhanced therapeutic effects in clinical practice. However, it requires complicated dosing regimens and is accompanied by increased toxicity. This study explored the combined effect of two therapeutic agents, daunorubicin (DNR) and homoharringtonine (HHT) in cell viability, apoptosis, and cell cycle in vitro and verified their synergistic effect. We encapsulated the two drugs into liposomes to construct a folic acid-modified co-delivery system (FA-DH-LP) to achieve an effective and safe therapeutic strategy. The FA-DH-LP was prepared by film hydration method. The resultant FA-DH-LP was homogeneously spherical and showed good blood compatibility with high encapsulation efficiency for DNR and HHT. The FA-DH-LP exhibited higher cellular uptake in HL60 and K562 cells and enhanced cytotoxicity than DNR/HHT co-delivery liposomes without folic acid modification (DH-LP) in vitro. In the HL60 subcutaneous xenotransplantation model, FA-DH-LP showed improved tumor targeting ability, anti-leukemia activity and safety profile superior to free combinational drugs and DH-LP after 18-day treatment. The results demonstrated that FA-DH-LP might present a promising delivery strategy to improve the efficacy of the two combinational chemotherapeutics while reducing toxicity.

Neuroprotective Effect of Alpha-asarone on the Rats Model of Cerebral Ischemia-Reperfusion Stroke via Ameliorating Glial Activation and Autophagy.

Alpha-asarone, a major active component isolated from Acorus gramineus, can affect brain functions and behaviors by multiple mechanisms. However, the effect of alpha-asarone on cerebral ischemia-reperfusion (CIR) stroke has not been reported. The present study aimed to investigate the neuroprotective effect of alpha-asarone and the involved mechanisms against CIR stroke. Rats were subjected to middle cerebral occlusion (MCAO) for 2 h. Then the drug or drug-free vehicle was intravenously injected to corresponding groups. After reperfusion for 24 h, the infarct volume was evaluated by Triphenyl Tetrazolium Chloride (TTC) staining. The neurofunctional recovery and post-stroke epilepsy were evaluated. Nissl and Hematoxylin-Eosin (H&E) staining were used for histological observation. We investigated the protective mechanism of alpha-asarone against the stroke. The results showed that alpha-asarone exhibited a desirable neuroprotective effect, manifested as reducing infarct volume and post-stroke epilepsy and improving neurological function. Histological and flow cytometry analysis revealed that alpha-asarone treatment alleviated cell injury and apoptosis in vivo and in vitro. Furthermore, alpha-asarone decreased GFAP, Iba-1, and LC3II/LC3I expression and increased the expression of p62. These results suggested that alpha-asarone attenuated the CIR stroke injury via ameliorating glial activation and autophagy.

Synthesis, antiepileptic effects, and structure-activity relationships of α-asarone derivatives: In vitro and in vivo neuroprotective effect of selected derivatives.

In the present study, we compared the antiepileptic effects of α-asarone derivatives to explore their structure-activity relationships using the PTZ-induced seizure model. Our research revealed that electron-donating methoxy groups in the 3,4,5-position on phenyl ring increased antiepileptic potency but the placement of other groups at different positions decreased activity. Besides, in allyl moiety, the optimal activity was reached with either an allyl or a 1-butenyl group in conjugation with the benzene ring. The compounds 5 and 19 exerted better neuroprotective effects against epilepsy in vitro (cell) and in vivo (mouse) models. This study provides valuable data for further exploration and application of these compounds as potential anti-seizure medicines.

Effects of ocean acidification and phosphate limitation on physiology and toxicity of the dinoflagellate Karenia mikimotoi.

This work demonstrated a 10-day batch culture experiment to test the physiology and toxicity of harmful dinoflagellate Karenia mikimotoi in response to ocean acidification (OA) under two different phosphate concentrations. Cells were previously acclimated in OA (pH = 7.8 and CO2 = 1100 µatm) condition for about three months before testing the responses of K. mikimotoi cells to a two-factorial combinations experimentation. This work measured the variation in physiological parameters (growth, rETR) and toxicity (hemolytic activity and its toxicity to zebrafish embryos) in four treatments, representing two factorial combinations of CO2 (450 and 1100 µatm) and phosphate concentration (37.75 and 4.67 umol l-1). Results: OA stimulated the faster growth, and the highest rETRmax in high phosphate (HP) treatment, low phosphate (LP) and a combination of high CO2 and low phosphate (HC*LP) inhibited the growth and Ek in comparison to low CO2*high phosphate (LCHP) treatment. The embryotoxicity of K. mikimotoi cells enhanced in all high CO2 (HC) conditions irrespective of phosphate concentration, but the EC50 of hemolytic activity increased in all high CO2 (HC) and low phosphate (LP) treatments in comparison of LCHP. Ocean acidification (high CO2 and lower pH) was probably the main factor that affected the rETRmax, hemolytic activity and embryotoxicity, but low phosphate was the main factor that affected the growth, α, and Ek. There were significant interactive effects of OA and low phosphate (LP) on growth, rETRmax, and hemolytic activity, but there were no significant effects on α, Ek, and embryotoxicity. If these results are extrapolated to the aquatic environment, it can be hypothesized that the K. mikimotoi cells were impacted significantly by future changing ocean (e.g., ocean acidification and nutrient stoichiometry).

Effects of ocean acidification and solar ultraviolet radiation on physiology and toxicity of dinoflagellate Karenia mikimotoi.

A batch culture experiment was conducted to study the interactive effects of ocean acidification (OA) and solar ultraviolet radiation (UVR, 280-400 nm) on the harmful dinoflagellate Karenia mikimotoi. Cells were incubated in 7-days trials under four treatments. Physiological (growth, pigments, UVabc) and toxicity (hemolytic activity and its toxicity to zebrafish embryos) response variables were measured in four treatments, representing two factorial combinations of CO2 (400 and 1000 µatm) and solar irradiance (with or without UVR). Toxic species K. mikimotoi showed sustained growth in all treatments, and there was not statistically significant difference among four treatments. Cell pigment content decreased, but UVabc and hemolytic activity increased in all HC treatments and PAB conditions. The toxicity to zebrafish embryos of K. mikimotoi was not significantly different among four treatments. All HC and UVR conditions and the combinations of HC*UVR (HC-PAB) positively affected the UVabc, hemolytic activity in comparison to the LC*P (LC-P) treatment, and negatively affected the pigments. Ocean acidification (OA) was probably the main factor that affected the chlorophyll-a (Chl-a) and UVabc, but UVR was the main factor that affected the carotenoid (Caro) and hemolytic activity. There were no significant interactive effects of OA*UVR on growth, toxicity to zebrafish embryos. If these results are extrapolated to the natural environment, it can be hypothesized that this strain (DP-C32) of K. mikimotoi cells have the efficient mechanisms to endure the combination of ocean acidification and solar UVR. It is assumed that this toxic strain could form harmful bloom and enlarge the threatening to coastal communities, marine animals, even human health under future conditions.