Reasearch on lipid metabolism of Plasmodium and antimalarial mechanism of artemisinin / 中国中药杂志

As a unicellular organism, Plasmodium displays a panoply of lipid metabolism pathways that are seldom found together in a unicellular organism. These pathways mostly involve the Plasmodium-encoded enzymatic machinery and meet the requirements of membrane synthesis during the rapid cell growth and division throughout the life cycle. Different lipids have varied synthesis and meta-bolism pathways. For example, the major phospholipids are synthesized via CDP-diacylglycerol-dependent pathway in prokaryotes and de novo pathway in eukaryotes, and fatty acids are synthesized mainly via type Ⅱ fatty acid synthesis pathway. The available studies have demonstrated the impacts of artemisinin and its derivatives, the front-line compounds against malaria, on the lipid metabolism of Plasmodium. Therefore, this article reviewed the known lipid metabolism pathways and the effects of artemisinin and its derivatives on these pathways, aiming to deepen the understanding of lipid synthesis and metabolism in Plasmodium and provide a theoretical basis for the research on the mechanisms and drug resistance of artemisinin and other anti-malarial drugs.

Effect of Dihydroartemisinin on Oxidative Damage and Energy Metabolism of HepG2 Cells and Its Synergistic Effect with Sorafenib / 中国实验方剂学杂志

Objective:To explore the inhibitory effect of dihydroartemisinin （DHA） on the proliferation of HepG2 cells， elucidate the mechanism from the perspectives of oxidative damage and energy metabolism， and discuss the possibility of combined use of DHA with sorafenib （Sora）. Method:Cell counting kit-8 （CCK-8） assay was used to obtain the 50% inhibitory concentration （IC₅₀） of DHA and Sora on HepG2 and SW480 cells and Chou-Talalay method was used to obtain the combination index （CI） of DHA and Sora. HepG2 cells were classified into the control group， DHA group （10 µmol·L^-1）， Sora group （5 µmol·L^-1）， and DHA + Sora group （DHA 10 µmol·L^-1， Sora 5 µmol·L^-1） and then incubated with corresponding drugs for 8-12 h. Seahorse XF glycolytic rate assay kit and cell mito stress test kit were employed to respectively detect the glycolysis function of cells and oxidative phosphorylation function of mitochondria. DCFH-DA and lipid peroxidation MDA assay kit were separately used to analyze the intracellular levels of reactive oxygen species （ROS） and malondialdehyde （MDA）. Western blot was applied to determine the intracellular levels of heme oxygenase-1 （HO-1） and glutamate-cysteine ligase catalytic subunit （GCLC）. Result:Compared with the control group， DHA alone inhibited the ATP synthesis in mitochondrial oxidative phosphorylation and glycolysis （<italic>P</italic><0.01）， increased the levels of intracellular ROS and MDA （<italic>P<</italic>0.05）， and decreased the levels of HO-1 and GCLC （<italic>P<</italic>0.05） in HepG2 cells. DHA and Sora had synergistic inhibitory effect on proliferation of HepG2 and SW480 cells， with CI < 0.90. The DHA + Sora group showed stronger suppression of ATP synthesis in mitochondrial oxidative phosphorylation and glycolysis （<italic>P</italic><0.01）， higher levels of intracellular ROS and MDA （<italic>P<</italic>0.01）， and lower levels of intracellular antioxidation-related proteins HO-1 and GCLC in HepG2 cells （<italic>P<</italic>0.01） than the DHA group. Conclusion:DHA may increase the level of MDA by reducing HO-1 and GCLC and increasing ROS in HepG2 cells， which results in mitochondria oxidative damage， restricts cell glycolysis and mitochondrial oxidative phosphorylation， and thus finally inhibits the proliferation of HepG2 cells. DHA and Sora have synergistic inhibitory effect on the proliferation of HepG2 and SW480 cells， and the mechanism may be related to the synergistic oxidative damage that affects the mitochondrial electron transport chain and suppresses cell energy metabolism.

Ferroptosis pathway and its intervention regulated by Chinese materia medica / 中国中药杂志

Ferroptosis is a new form of regulated cell death which is different from apoptosis, necrosis and autophagy, and results from iron-dependent lipidperoxide accumulation. Now, it is found that ferroptosis is involved in multiple physiological and pathological processes, such as cancer, arteriosclerosis, neurodegenerative diseases, diabetes, antiviral immune response, acute renal failure, hepatic and heart ischemia/reperfusion injury. On the one hand, it could be found the appropriate drugs to promote ferroptosis to clear cancer cells and virus infected cells, etc. On the other hand, we could inhibit ferroptosis to protect healthy cells. China has a wealth of traditional Chinese medicine resources. Chinese medicine contains a variety of active ingredients that regulate ferroptosis. Here, this paper reported the research of ferroptosis pathway, targets of its inducers and inhibitors that have been discovered, and the regulatory effects of the discovered Chinese herbs and its active ingredients on ferroptosis to help clinical and scientific research.

Research progress on heme metabolism in intraerythrocytic plasmodium / 中国中药杂志

Heme is a key metabolic factor in all life. Malaria parasite has de novo heme-biosynthetic pathway, however the growth and development of parasite depend on the hemoglobin-derived heme metabolism process during the intraerythrocytic stages, such as the ingestion and degradation of hemoglobin in the food vacuole. The hemoglobin metabolism in the food vesicles mainly includes four aspects: hemoglobin transport and intake, hemoglobin enzymolysis to produce heme, heme polymerization into malarial pigment, and heme transport via the food vacuole. The potential mechanisms of antimalarial drugs,such as chloroquine, artemisinin and atovaquone may be related to this process. The main four aspects of this metabolic process, key metabolic enzymes, effects of antimalarial drugs on the process and their potential mechanism of action would be summarized in this paper, providing ideas for rational use and mechanism exploration of similar drugs.

Protective effects of three phenylallyl compounds from Guizhi decoction ox-LDL-induced oxidative stress injury of human brain microvascular endothelial cells / 中国中药杂志

The main objective of this research is to observe protective effects of three phenylallyl compounds(cinnamyl alcohol,cinnamaldehyde and cinnamic acid)from Guizhi decoction against ox-LDL-induced oxidative stress injury on human brain microvascular endothelial cells(HBMEC).In this study,the toxicity and optimal protective concentration of three phenylallyl compounds from Guizhi decoction were determined by MTT assay.The HBMEC were divided into control group(DMSO),model group(ox-LDL),tert-butylhydroquinone (t-BHQ) group,cinnamyl alcohol group, cinnamaldehyde group and cinnamic acid group.The model group were treated with ox-LDL (50 mg•L⁻¹)for 24 h,other groups were separately treated with t-BHQ, cinnamyl alcohol, cinnamaldehyde and cinnamic acid of 20 μmol•L⁻¹, and exposed to ox-LDL (50 mg•L⁻¹) for 24 h at the same time.The survival rate of HBMEC was detected by MTT assay,reactive oxygen species(ROS) production of injured cells were detected using laser scanning confocal microscope (LSCM),the content of SOD, MDA, eNOS and NO in HBMEC was determined by ELISA, and the expressions of Nrf2 mRNA were detected by quantitative Real-time PCR(qRT-PCR).The results shows that oxidative stress injury of HBMEC could be induced by ox-LDL, the three phenylallyl compounds from Guizhi decoction did not affect morphology and viability of normal HBMEC.Compared with model group, the three phenylallyl compounds from Guizhi decoction could improve the above oxidative stress status and up-regulate Nrf2 mRNA expressions in injured HBMEC(P<0.05, P<0.01) .These findings suggested that the three phenylallyl compounds from Guizhi decoction have certain protective effects against ox-LDL-induced oxidative stress injury on HBMEC(cinnamaldehyde> t-BHQ> cinnamic acid>cinnamyl alcohol),the protective mechanism maybe related to regulation of antioxidant enzymes gene expression in HBMEC by Nrf2.

TRPV1 channel-mediated thermogenesis is a common mode for the Chinese pungent-hot or pungent-warm herbs to demonstrate their natures / 药学学报

To further uncover the scientific significance and molecular mechanism of the Chinese herbs with pungent hot or warm natures, endogenous and exogenous expression systems were established by isolation of dorsal root ganglion (DRG) neurons and transfection of HEK293 cells with TRPV1 channel gene separately. On this basis, the regulation action of capsaicin, one main ingredient from chili pepper, on TRPV1 channel was further explored by using confocal microscope. Besides, the three-sites one-unit technique and method were constructed based on the brown adipose tissue (BAT), anal and tail skin temperatures. Then the effect of capsaicin on mouse energy metabolism was evaluated. Both endogenous and exogenous TRPV1 channel could be activated and this action could be specifically blocked by the TRPV1 channel inhibitor capsazepine. Simultaneously, the mice's core body temperature and BAT temperature fall down and then go up, accompanied by the increase of temperature of the mice's tail skin. Promotion of the energy metabolism by activation of TRPV1 channel might be the common way for the pungent-hot (warm) herbs to demonstrate their natures.

Chemistry and pharmacology of Siraitia grosvenorii: a review / 中国天然药物

Siraitia grosvenorii is a perennial herb endemic to Guangxi province of China. Its fruit, commonly known as Luo hanguo, and has been used for hundreds of years as a natural sweetener and as a traditional medicine for the treatment of pharyngitis, pharyngeal pain, as well as an anti-tussive remedy in China. Based on ninety-three literary sources, this review summarized the advances in chemistry, biological effects, and toxicity research of S. grosvenorii during the past 30 years. Several different classes of compounds have been isolated or detected from various parts of S. grosvenorii, mainly triterpenoids, flavonoids, polysaccharides, amino acids, and essential oils. Various types of extracts or individual compounds derived from this species exhibited a wide array of biological effects e.g. anti-tussive, phlegm-relieving, anti-oxidant, immunomodulatory, liver-protecting, glucose-lowering, and anti-microbial. The existing research has shown that extracts and individual compounds from S. grosvenorii are basically non-toxic. Finally, some suggestions for further research on specific chemical and pharmacological properties of S. grosvenorii are proposed in this review.

Reciprocal effects of Guizhi decoction to the Guizhi decoction syndrome by toll-like receptor mRNA expression and cytokines secretion / 中国结合医学杂志

<p><b>OBJECTIVE</b>To explore the pathological mechanisms of Guizhi Decoction () syndrome and the therapeutic molecular mechanisms of the Guizhi Decoction, Mahuang Decoction (), Sangju Decoction ( ) and Yinqiao Powder (), as well as the potentially biological basis that Guizhi Decoction is most effective only for the patients with Guizhi Decoction syndrome in clinical practice.</p><p><b>METHODS</b>We first got serum samples from the patients suffering from both upper respiratory tract infection and Guizhi Decoction syndrome identified by the doctors of Chinese medicine (CM) in the clinic. Four formulas with therapeutic actions of pungent warmth or pungent coolness for superficial syndromes were chosen and four kinds of rat serum samples each containing one of the above-mentioned herbal formulas were collected, then the effects of Guizhi Decoction syndromes' patient serum as well as the effects of sera containing the formulas after being stimulated by the patient serum samples on both the mRNA expression of certain toll-like receptor (TLR) subtypes and the release of some inflammatory cytokines in RAW264.7 cells were tested and analyzed in vitro.</p><p><b>RESULTS</b>The expression of TLR-3, TLR-4 and TLR-9 mRNA among the 9 tested TLR subforms were up-regulated in the macrophages stimulated by the sera from untreated upper respiratory infection patients with the Guizhi Decoction syndrome (symptomcomplex). The products such as interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α and interferon (IFN)-β from stimulated macrophages through TLR signaling pathways were also increased correspondingly. Interestingly, the changes induced by the Guizhi Decoction syndrome patients' sera were masked significantly after the macrophages were incubated with the sera from donors treated with Guizhi Decoction. Similarly, the three other exterior-releasing formulas were all effective in reversing the up-regulated changes of certain TLR subforms to different degrees, but both the number of targeted TLRs and efficacy of them seemed to be inferior to that of Guizhi Decoction.</p><p><b>CONCLUSION</b>Evidence from these experiments might contribute to the scientific explanation of both the pharmacological mechanisms of Guizhi Decoction and also the CM theory that Guizhi Decoction is specifically prescribed for the treatment of Guizhi Decoction syndrome (The gearing formula to the symptom-complex).</p>

Effect of Shensu Yin on the expression of toll-like receptors and the downstream signaling components on RAW 264.7 cells / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the influences of Shensu Yin to RAW 264.7 on the expression of TLR3, TLR4 and the factors of the downstream in RAW 264. 7 cells.</p><p><b>METHOD</b>RAW 264.7 cell line was stimulated with Lipopolysaccharide and POLY I: C, respectively, and treated with the drug serum of Shensuyin simultaneously. 24 hours later, collected the supernatant and measured the inflammatory factors TNF-alpha and IFN-beta, extracted mRNA and measured the expression of TLR3, TLR4 and other correlated indexes of the downstream, analyzed and evaluated Shensu Yin's substance basis of pharmacodynamic actions.</p><p><b>RESULT</b>Shensu Yin drug serum depressed the expression of TLR4, MyD88, TRAF-6, TRAM and TRIF mRNA, as a result, it decreased the amount of TNF-alpha and IFN-beta.</p><p><b>CONCLUSION</b>Depressing the expression of TLR3, MyD88, TRAM and TRIF mRNA may be the elementary basis of Shensu Yin to play heat-clearing and detoxicating effect.</p>

Structure-activity relationship of phenylallyl compounds inhibiting PGE2 release in mouse cerebral microvascular endothelial cells induced by IL-1beta / 药学学报

To observe the effects of phenylallyl compounds on prostaglandin E2 (PGE2) release in mouse cerebral microvascular endothelial cells (bEnd. 3) stimulated by IL-1beta, and to analyze their structure-activity relationship. Different concentrations of phenylallyl compounds were added separately, and the content of PGE2 induced by IL-1beta in the culture media was measured by ELISA assay. The 50% inhibitory concentration (IC50) of PGE2 was calculated. Studies showed that phenylallyl compounds could affect the PGE2 release differently in bEnd. 3 cells induced by IL-1beta. Close relationships were shown between the inhibitory activities and the location and number of the substituent groups. In conclusion, phenylallyl compounds exhibited inhibitory activities at different extent on PGE2 release in bEnd. 3 cells stimulated by IL-1beta and presented certain structure-activity relationship.

Effect of 2-methoxycinnamaldehyde on activity of COX and PGE2 release in cerebral microvascular endothelial cells stimulated by IL-1 / 中国中药杂志

<p><b>OBJECTIVE</b>To observe the effect of 2-methoxycinnamaldehyde (isolated from fraction A of Guizhi Tang) on activity of COX and PGE2 release in rat cerebral microvascular endothelial cells (rCMEC) stimulated by IL-1.</p><p><b>METHOD</b>rCMEC were cultured, and identified by immunohistochemistry for von Willebrand factor (VIII factor, a marker for all endothelial cells) in cytoplasm of the cells. Different concentrations of 2-methoxycinnamaldehyde were added respectively and incubated for 3 hours, then stimulated for another 12 hours by IL-1. Activities of COX-1 and COX-2 in rCMEC, and production of PGE2 in the conditioned media were measured by ELISA.</p><p><b>RESULT</b>Positive immunostaining for VIII factor was present diffusely in the cytoplasm of > 90% rCMEC. After being exposed to 30 ng x mL(-1) IL, the activity of COX-2 in rCMEC and the production of PGE2 in conditioned media were higher than those of control group, while there was no difference on activity of COX-1 in the two groups. 2-methoxycinnamaldehyde could down-regulate them in concentration-dependently, and significant differences on the activity of COX-2 and amount of PGE2 were showed in 200 microg x mL(-1) concentration.</p><p><b>CONCLUSION</b>2-methoxycinnamaldehyde can affect the PGE2 release in rCMEC induced by IL-1, which might be related with its inhibition on the activity of COX-2.</p>

Effect of guizhi tang and its active components on the fever induced by EP3 agonist / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effect of Guizhi Tang and its active components on the fever induced by EP3 receptor agonist sulprostone in rats.</p><p><b>METHOD</b>The rise in body temperature evoked by a LCV(lateral cerebroventricle)-injection of sulprostone was compared with that of sulprostone induced-fever rats pretreated with Guizgi Tang and its active compounds, cinnamaldehyde, cinnamic acid and total glucosides of paeony.</p><p><b>RESULT</b>Pretreatments with Guizhi Tang and cinnamaldehyde inhibited the rise in body temperature induced by sulprostone, while cinnamic acid tended to augment the fever. The sulprostone-induced fever was blocked by an ip pretreatment of total glucosides of paeony even below the basement.</p><p><b>CONCLUSION</b>Present data suggest that interruption with the down-stream events of EP3 receptor may contribute to the antipyretic action of Guizhi Tang, cinnamaldehyde and the total glucosides of paeony, while cinnamic acid may have no such effect.</p>