[Effect on Danggui Shaoyao Powder on mitophagy in rat model of Alzheimer's disease based on PINK1-Parkin pathway].

This study investigated the mechanism of Danggui Shaoyao Powder(DSP) against mitophagy in rat model of Alzheimer's disease(AD) induced by streptozotocin(STZ) based on PTEN induced putative kinase 1(PINK1)-Parkin signaling pathway. The AD rat model was established by injecting STZ into the lateral ventricle, and the rats were divided into normal group, model group, DSP low-dose group(12 g·kg~(-1)·d~(-1)), DSP medium-dose group(24 g·kg~(-1)·d~(-1)), and DSP high-dose group(36 g·kg~(-1)·d~(-1)). Morris water maze test was used to detect the learning and memory function of the rats, and transmission electron microscopy and immunofluorescence were employed to detect mitophagy. The protein expression levels of PINK1, Parkin, LC3BⅠ/LC3BⅡ, and p62 were assayed by Western blot. Compared with the normal group, the model group showed a significant decrease in the learning and memory function(P<0.01), reduced protein expression of PINK1 and Parkin(P<0.05), increased protein expression of LC3BⅠ/LC3BⅡ and p62(P<0.05), and decreased occurrence of mitophagy(P<0.01). Compared with the model group, the DSP medium-and high-dose groups notably improved the learning and memory ability of AD rats, which mainly manifested as shortened escape latency, leng-thened time in target quadrants and elevated number of crossing the platform(P<0.05 or P<0.01), remarkably activated mitophagy(P<0.05), up-regulated the protein expression of PINK1 and Parkin, and down-regulated the protein expression of LC3BⅠ/LC3BⅡ and p62(P<0.05 or P<0.01). These results demonstrated that DSP might promote mitophagy mediated by PINK1-Parkin pathway to remove damaged mitochondria and improve mitochondrial function, thereby exerting a neuroprotective effect.

GDH promotes isoprenaline-induced cardiac hypertrophy by activating mTOR signaling via elevation of α-ketoglutarate level.

Numerous studies reveal that metabolism dysfunction contributes to the development of pathological cardiac hypertrophy. While the abnormal lipid and glucose utilization in cardiomyocytes responding to hypertrophic stimuli have been extensively studied, the alteration and implication of glutaminolysis are rarely discussed. In the present work, we provide the first evidence that glutamate dehydrogenase (GDH), an enzyme that catalyzes conversion of glutamate into ɑ-ketoglutarate (AKG), participates in isoprenaline (ISO)-induced cardiac hypertrophy through activating mammalian target of rapamycin (mTOR) signaling. The expression and activity of GDH were enhanced in cultured cardiomyocytes and rat hearts following ISO treatment. Overexpression of GDH, but not its enzymatically inactive mutant, provoked cardiac hypertrophy. In contrast, GDH knockdown could relieve ISO-triggered hypertrophic responses. The intracellular AKG level was elevated by ISO or GDH overexpression, which led to increased phosphorylation of mTOR and downstream effector ribosomal protein S6 kinase (S6K). Exogenous supplement of AKG also resulted in mTOR activation and cardiomyocyte hypertrophy. However, incubation with rapamycin, an mTOR inhibitor, attenuated hypertrophic responses in cardiomyocytes. Furthermore, GDH silencing protected rats from ISO-induced cardiac hypertrophy. These findings give a further insight into the role of GDH in cardiac hypertrophy and suggest it as a potential target for hypertrophy-related cardiomyopathy.

[Baicalin inhibits LPS/IFN-γ-induced inflammation via TREM2/TLR4/NF-κB pathway in BV2 cells].

This study investigated the mechanism of baicalin on lipopolysaccharide(LPS)/interferon γ(IFN-γ)-induced inflammatory microglia based on the triggering receptor expressed on myeloid cells 2(TREM2)/Toll-like receptor 4(TLR4)/nuclear factor kappaB(NF-κB) pathway. Specifically, LPS and IFN-γ were used to induce inflammation in mouse microglia BV2 cells. Then the normal group, model group, low-dose(5 µmol·L~(-1)) baicalin group, medium-dose(10 µmol·L~(-1)) baicalin group, high-dose(20 µmol·L~(-1)) baicalin group, and minocycline(10 µmol·L~(-1)) group were designed. Cell viability was detected by CCK-8 assay and cell morphology was observed under bright field. The expression of interleukin-1ß(IL-1ß), interleukin-4(IL-4), inducible nitric oxide synthase(iNOS), interleukin-6(IL-6), interleukin-10(IL-10), and arginase-1(Arg-1) mRNA was detected by real-time quantitative PCR, the protein expression of tumor necrosis factor-α(TNF-α), IL-1ß, TREM2, TLR4, inhibitor kappaB-alpha(IκBα), p-IκBα, NF-κB p65 and p-NF-κB p65 by Western blot, and transfer of NF-κB p65 from cytoplasm to nucleus by cellular immunofluorescence. Compared with the normal group, most of the BV2 cells in the model group tended to demonstrate the pro-inflammatory M1 amoeba morphology, and the model group showed significant increase in the mRNA levels of IL-1ß, IL-6, and iNOS, decrease in the mRNA levels of IL-4, IL-10, and Arg-1(P<0.01), rise of the protein expression of TNF-α, IL-1ß, TLR4, p-IκBα, and p-NF-κB p65(P<0.01), reduction in TREM2 protein expression, and increase in the expression of NF-κB p65 in nucleus. Compared with the model group, baicalin groups and minocycline group showed the recovery of BV2 cell morphology, significant decrease in the mRNA levels of IL-1ß, IL-6 and iNOS, increase in the mRNA levels of IL-4, IL-10, and Arg-1(P<0.01), reduction in the protein expression of TNF-α, IL-1ß, TLR4, p-IκBα, and p-NF-κB p65(P<0.05), rise of TREM2 protein expression, and decrease in the expression of NF-κB p65 in nucleus. In summary, these results suggest that baicalin can regulate the imbalance between TREM2 and TLR4 of microglia and inhibit the activation of downstream NF-κB, thus promoting the polarization of microglia from pro-inflammatory phenotype to anti-inflammatory phenotype.

[Study on patterns and characteristics of in vivo tissue distribution of anti-inflammatory extract of Tetrastigma hemsleyanum aerial part in healthy and inflammatory pathological model rats].

The concentrations of seven anti-inflammatory components in blood and tissues were determined by UPLC-MS/MS after oral administration of Tetrastigma hemsleyanum aerial part(THAA) in healthy and inflammatory pathological model rats. The determination was carried out by using positive and negative ion switching technique, and multiple reaction monitoring(MRM) mode. The tissue distributions of the seven components in different physiological states were compared, and the patterns and characteristics of the effective components of THAA were studied. The results revealed that the seven effective components have large drug-time-curve areas(AUC) in heart, brain, small intestine, and stomach in both normal rats and inflammatory pathological model rats. This suggests that the anti-inflammatory effective component groups in THAA extract can all penetrate the blood-brain barrier, and have a large distribution area in gastrointestinal tract. It is inferred that gastrointestinal reabsorption may be one of the causes of the bimodal distribution of the drug-time curve of the drug blood distribution graph. As compared to normal rats, the effective component groups in THAA extract have higher drug-time curve area(AUC) in heart, brain, small intestine, stomach, liver, spleen, lung, kidney, and muscle of inflammatory pathological model rats. Among them, the effective component groups have the largest distribution area in heart, brain, small intestine, and stomach. This suggests that the binding force of organ tissues and drugs in the body may change under pathological conditions. It is speculated that the heart, brain, small intestine, and stomach may be the target tissues of THAA to produce anti-inflammatory effect. The retention times of THAA effective component groups in various organ tissues of rats in different physiological states are all relatively short, and do not have much difference. This suggests that no effective component accumulates in body, and that the pathological state of inflammation does not affect the onset times of the effective component groups. This experiment elucidates the patterns and characteristics of the in vivo target-effecting tissue distribution of THAA anti-inflammatory extract, and provides an experimental basis for clinical treatment.

Ca2+ signalling plays a role in celastrol-mediated suppression of synovial fibroblasts of rheumatoid arthritis patients and experimental arthritis in rats.

BACKGROUND AND PURPOSE: Celastrol exhibits anti-arthritic effects in rheumatoid arthritis (RA), but the role of celastrol-mediated Ca2+ mobilization in treatment of RA remains undefined. Here, we describe a regulatory role for celastrol-induced Ca2+ signalling in synovial fibroblasts of RA patients and adjuvant-induced arthritis (AIA) in rats. EXPERIMENTAL APPROACH: We used computational docking, Ca2+ dynamics and functional assays to study the sarcoplasmic/endoplasmic reticulum Ca2+ ATPase pump (SERCA). In rheumatoid arthritis synovial fibroblasts (RASFs)/rheumatoid arthritis fibroblast-like synoviocytes (RAFLS), mechanisms of Ca2+ -mediated autophagy were analysed by histological, immunohistochemical and flow cytometric techniques. Anti-arthritic effects of celastrol, autophagy induction, and growth rate of synovial fibroblasts in AIA rats were monitored by microCT and immunofluorescence staining. mRNA from joint tissues of AIA rats was isolated for transcriptional analysis of inflammatory genes, using siRNA methods to study calmodulin, calpains, and calcineurin. KEY RESULTS: Celastrol inhibited SERCA to induce autophagy-dependent cytotoxicity in RASFs/RAFLS via Ca2+ /calmodulin-dependent kinase kinase-ß-AMP-activated protein kinase-mTOR pathway and repressed arthritis symptoms in AIA rats. BAPTA/AM hampered the in vitro and in vivo effectiveness of celastrol. Inflammatory- and autoimmunity-associated genes down-regulated by celastrol in joint tissues of AIA rat were restored by BAPTA/AM. Knockdown of calmodulin, calpains, and calcineurin in RAFLS confirmed the role of Ca2+ in celastrol-regulated gene expression. CONCLUSION AND IMPLICATIONS: Celastrol triggered Ca2+ signalling to induce autophagic cell death in RASFs/RAFLS and ameliorated arthritis in AIA rats mediated by calcium-dependent/-binding proteins facilitating the exploitation of anti-arthritic drugs based on manipulation of Ca2+ signalling.

Following "the Roots" of Kratom (Mitragyna speciosa): The Evolution of an Enhancer from a Traditional Use to Increase Work and Productivity in Southeast Asia to a Recreational Psychoactive Drug in Western Countries.

The use of substances to enhance human abilities is a constant and cross-cultural feature in the evolution of humanity. Although much has changed over time, the availability on the Internet, often supported by misleading marketing strategies, has made their use even more likely and risky. This paper will explore the case of Mitragyna speciosa Korth. (kratom), a tropical tree used traditionally to combat fatigue and improve work productivity among farm populations in Southeast Asia, which has recently become popular as novel psychoactive substance in Western countries. Specifically, it (i) reviews the state of the art on kratom pharmacology and identification; (ii) provides a comprehensive overview of kratom use cross-culturally; (iii) explores the subjective experiences of users; (iv) identifies potential risks and side-effects related to its consumption. Finally, it concludes that the use of kratom is not negligible, especially for self-medication, and more clinical, pharmacological, and socioanthropological studies as well as a better international collaboration are needed to tackle this marginally explored phenomenon.

[Influence of electroacupuncture stimulation of "tianshu" (ST 25), "quchi" (LI 11) and "shangjuxu" (ST 37) and their pairs on gastric motility in the rat].

OBJECTIVE: To observe the effect of electroacupuncture (EA) stimulation of different acupoints or acupoint pairs on gastric motility so as to explore their modulation regularities under different conditions. METHODS: SD rats were randomly divided into normal control, starvation (food-deprivation for 24 h), atropine (antagonist for M-receptor), acetylcholine (Ach, agonist for M-receptor), propranolol (antagonist for beta-receptor) and clenbuterol (agonist for beta 2-receptor) and paired-acupoint groups (30 rats/group). The intragastric pressure was measured via a pressure transducer connected to a balloon inserted in the stomach cavity. EA (2 Hz /15 Hz, 2 mA) was applied to the left "Tianshu" (ST 25),"Quchi" (LI 11) and "Shangjuxu" (ST 37) which were formed in pairs: ST 25-LI 11, ST 25-ST 37 and LI 11-ST 37 for 2 min following intravenous injection of atropine (0.1%, 0.8 mL/kg, 40 microL x min(-1) x kg(-1)), 0.1% acetylcholine (20 microL x min(-1) x kg(-1)), 0. 2% clenbuterol (80 microL x min(-1) x kg(-1)) and 0.4% propranolol (1 mL/kg,40 microL x min(-1) x kg(-1)) under food-deprivation conditions. RESULTS: After intravenous injection of atropine and clenbuterol, the intragastric pressure were decreased significantly (P < 0.05), while after administration of Ach and propranolol, the intragastric pressure increased markedly (P < 0.05). Under normal and starvation conditions, and after intravenous administration of M-receptor antagonist (atropine) and agonist (Ach), beta-receptor antagonist (propranolol) and agonist (clenbuterol), EA stimulation of ST 25 produced an apparently inhibitory effects on gastric motility (80.00%, 86.67%, 76.67%, 86.67%, 73.33% and 86.67%, respectively) and intragatric pressure (P < 0.05) with the tendency being starvation > normal, acetylcholine > atropine and clenbuterol > propranolol. Whereas EA stimulation of LI 11 and ST 37 mainly produced an excitatory effect on gastric motility (60.00%, 56.67%, 93.33%, 40.00%, 53.33% and 50.00%, respectively for LI 11; 66.67%, 60.00%, 80.00%, 53.33%, 46.67% and 73.33%, respectively for ST 37). Following EA stimulation of the paired-acupoint groups, ST 25-ST 37 induced a predominately inhibitory effect on gastric motility (50.00%) and intragastric pressure, while LI 11-ST 37 stimulation had a principally excitatory effect on gastric motility (53.33%), and ST 25-LI 11 showed no apparent effect (50.00%). CONCLUSION: EA stimulation of ST 25 area at the abdomen produces a predominant inhibitory effect on gastric motility, while EA of LI 11 and ST 37 on the upper and lower limbs induces an excitatory effect on gastric movement, when applied in pairs, EA of ST 25-ST 37 suppresses the gastric activity, and LI 11-ST 37 promotes the gastric activity, suggesting a specificity of the effect of different acupoint stimulation.