Fabrication of apigenin nanoparticles using antisolvent crystallization technology: A comparison of supercritical antisolvent, ultrasonic-assisted liquid antisolvent, and high-pressure homogenization technologies.

Flavonoids have many positive pharmacological properties, such as antioxidant, antitumor, and anti-inflammatory activities. However, factors such as low water solubility and low dissolution rate limit their use. To overcome their poor solubility, carrier-free apigenin (API) microparticles and nanoparticles were prepared using three types of antisolvent precipitation technologies: supercritical antisolvent (SCF) technology, ultrasonic-assisted liquid antisolvent (UAL) technology, and high-pressure homogenization (HPH) technology. All three technologies can produce uniform tiny particles. However, the API particles obtained using these different techniques show subtle differences in terms of physical and chemical properties and biological activity. The preparation, characterization, and potential use of API microparticles and nanoparticles to improve in vitro release were studied. The resulting API particles were investigated and compared using Fourier-transform infrared spectroscopy, differential scanning calorimetry, X-ray powder diffraction, and scanning electron microscopy. We determined the optimum conditions for SCF, UAL, and HPH technologies to produce API microparticles and nanoparticles. The antioxidant and antitumor properties of the API particles were also investigated. The results demonstrated that the reduced particle size of the APIs prepared via SCF, UAL, and HPH technologies contributed to the enhanced dissolution rate, which in turn enhanced API bioactivity.

Huang-Lian-Jie-Du-Decotion induced protective autophagy against the injury of cerebral ischemia/reperfusion via MAPK-mTOR signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Huang-Lian-Jie-Du-Decotion (HLJDD, Hwangryun-Hae-Dok-Decotion in Japan), an ancient antipyretic and detoxifying traditional Chinese medicine formula, was reported to have protective effect on ischemic stroke. AIM OF THE RESEARCH: To investigate the therapeutic effect of HLJDD on ischemic stroke and explore its mode of action. MATERIAL AND METHODS: A model of ischemic stroke in the rat was established after transient middle cerebral artery occlusion (MCAO) followed by reperfusion. Rats were assigned randomly to groups of control, sham, transient ischemia/reperfusion (I/R), and three treatment groups by HLJDD at 2.5, 5.0, 10.0mg/kg. The neurological deficit, the cerebral infarct size, morphology abnormality, biochemical parameters were examined, and the levels of relevant proteins were determined by immunoblotting analysis to evaluate the protective effects of HLJDD on ischemic stroke and explore the underlying mechanism. RESULTS: Compared with I/R group, HLJDD significantly ameliorated neurological deficit and histopathology changes, decreased infarct area, and restored the levels of biochemical indicators including nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), glutathione disulfide (GSSG), total superoxide dismutase (T-SOD), Cu/Zn-SOD, Mn-SOD and glutathione peroxidase (GSH-PX). HLJDD also notably elevated the levels of microtubule-associated protein 1 light chain 3 (LC3), Beclin-1, and other autophagy related genes (Atgs), promoted the activation of extracellular signal-regulated kinases (ERK), protein kinase B (Akt), 3-phosphoinositide-dependent kinase (PDK1), and inhibited the activation of mammalian target of rapamycin (mTOR), c-Jun N-terminal protein kinases (JNK), p38, phosphatase and tensin homolog (PTEN). CONCLUSION: HLJDD showed neuroprotective effects on ischemic stroke, at least in part to the induced protective autophagy via the regulation of mitogen-activated protein kinase (MAPK) signals. This Akt-independent protective autophagy is favorable in the treatment of stroke, avoiding unfavorable side-effects associated with the inactivation of Akt. The efficacy of HLJDD on ischemic stroke and its safety warranted by its long-term clinical use in traditional Chinese medicine favored further study to develop HLJDD as an effective therapeutic agent to treat ischemic stroke.

¹H NMR-based metabolomics approach to evaluate the effect of Xue-Fu-Zhu-Yu decoction on hyperlipidemia rats induced by high-fat diet.

An NMR-based metabolomics approach was conducted to holisticly explore the effect of XFZYD (a traditional Chinese medicine formula) on high-fat diet induced hyperlipidemia rats with one of the commonly used antihyperlipidemic agents, simvastatin as the positive control. NMR spectra from blood plasma combined with statistical analysis revealed compounds distinguishing hyperlipidemia rats from normal control rats. XFZYD could ameliorate hyperlipidemia by intervening in some major metabolic pathways, such as decreasing the accumulation of ketone body (ß-hydroxybutyrate) and acetyl-glycoproteins, enhancing glutathione (GSH) biosynthesis, partially reversing energy and lipid metabolism disturbance. Oral administration of XFZYD could also be helpful to hyperlipidemia rats in bettering the serum chemistry profile. The combined results demonstrated that XFZYD could ameliorate the hyperlipidemic symptoms in a global scale and restore the abnormal metabolic state to a near normal level in a time-dependent pattern.