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1.
Biochemistry ; 60(24): 1933-1946, 2021 06 22.
Article in English | MEDLINE | ID: mdl-34077175

ABSTRACT

Helicobacter pylori is a Gram-negative bacterium that is responsible for gastric and duodenal ulcers. H. pylori uses the unusual mqn pathway with aminofutalosine (AFL) as an intermediate for menaquinone biosynthesis. Previous reports indicate that hydrolysis of AFL by 5'-methylthioadenosine nucleosidase (HpMTAN) is the direct path for producing downstream metabolites in the mqn pathway. However, genomic analysis indicates jhp0252 is a candidate for encoding AFL deaminase (AFLDA), an activity for deaminating aminofutolasine. The product, futalosine, is not a known substrate for bacterial MTANs. Recombinant jhp0252 was expressed and characterized as an AFL deaminase (HpAFLDA). Its catalytic specificity includes AFL, 5'-methylthioadenosine, 5'-deoxyadenosine, adenosine, and S-adenosylhomocysteine. The kcat/Km value for AFL is 6.8 × 104 M-1 s-1, 26-fold greater than that for adenosine. 5'-Methylthiocoformycin (MTCF) is a slow-onset inhibitor for HpAFLDA and demonstrated inhibitory effects on H. pylori growth. Supplementation with futalosine partially restored H. pylori growth under MTCF treatment, suggesting AFL deamination is significant for cell growth. The crystal structures of apo-HpAFLDA and with MTCF at the catalytic sites show a catalytic site Zn2+ or Fe2+ as the water-activating group. With bound MTCF, the metal ion is 2.0 Å from the sp3 hydroxyl group of the transition state analogue. Metabolomics analysis revealed that HpAFLDA has intracellular activity and is inhibited by MTCF. The mqn pathway in H. pylori bifurcates at aminofutalosine with HpMTAN producing adenine and depurinated futalosine and HpAFLDA producing futalosine. Inhibition of cellular HpMTAN or HpAFLDA decreased the cellular content of menaquinone-6, supporting roles for both enzymes in the pathway.


Subject(s)
Helicobacter pylori/metabolism , Nucleosides/metabolism , Vitamin K 2/metabolism , Catalytic Domain , Crystallography, X-Ray/methods , Deoxyadenosines , Helicobacter pylori/chemistry , Helicobacter pylori/enzymology , Models, Molecular , N-Glycosyl Hydrolases/chemistry , N-Glycosyl Hydrolases/metabolism , Nucleosides/chemistry , Purine-Nucleoside Phosphorylase/chemistry , Substrate Specificity , Thionucleosides , Vitamin K 2/analogs & derivatives
2.
Front Physiol ; 9: 491, 2018.
Article in English | MEDLINE | ID: mdl-29780330

ABSTRACT

Aim: Combined use of herbal medicines in patients underwent dual antiplatelet therapy (DAPT) might cause bleeding or thrombosis because herbal medicines with anti-platelet activities may exhibit interactions with DAPT. In this study, we tried to use a feedback system control (FSC) optimization technique to optimize dose strategy and clarify possible interactions in combined use of DAPT and herbal medicines. Methods: Herbal medicines with reported anti-platelet activities were selected by searching related references in Pubmed. Experimental anti-platelet activities of representative compounds originated from these herbal medicines were investigated using in vitro assay, namely ADP-induced aggregation of rat platelet-rich-plasma. FSC scheme hybridized artificial intelligence calculation and bench experiments to iteratively optimize 4-drug combination and 2-drug combination from these drug candidates. Results: Totally 68 herbal medicines were reported to have anti-platelet activities. In the present study, 7 representative compounds from these herbal medicines were selected to study combinatorial drug optimization together with DAPT, i.e., aspirin and ticagrelor. FSC technique first down-selected 9 drug candidates to the most significant 5 drugs. Then, FSC further secured 4 drugs in the optimal combination, including aspirin, ticagrelor, ferulic acid from DangGui, and forskolin from MaoHouQiaoRuiHua. Finally, FSC quantitatively estimated the possible interactions between aspirin:ticagrelor, aspirin:ferulic acid, ticagrelor:forskolin, and ferulic acid:forskolin. The estimation was further verified by experimentally determined Combination Index (CI) values. Conclusion: Results of the present study suggested that FSC optimization technique could be used in optimization of anti-platelet drug combinations and might be helpful in designing personal anti-platelet therapy strategy. Furthermore, FSC analysis could also identify interactions between different drugs which might provide useful information for research of signal cascades in platelet.

3.
Zhongguo Zhong Yao Za Zhi ; 40(24): 4908-13, 2015 Dec.
Article in Chinese | MEDLINE | ID: mdl-27245042

ABSTRACT

Totally 96 elderly patients with spleen-kidney Yang deficiency type hypertension were selected in this study. Patients were randomly divided into study and control group. It was treated with the Jingui Shenqi pill combined nifedipine sustained-release tablets in the study group and only nifedipine sustained-release tablets for the control group. Meanwhile, the clinical features including reducing blood pressure, blood lipid and traditional Chinese medicine (TCM) syndromes of the two groups were observed pre and post treatment. Finally, the results showed that it could significantly reduce the hypertensive, hyperlipidemia and TCM syndromes in the study group compared with the control group (P < 0.05), which indicated that the combination of the Jingui Shenqi pill with nifedipine sustained-release tablets was effective for the patients with hypertension with spleen-kidney Yang deficiency type, especially for decreasing TCM syndromes and the blood lipid.


Subject(s)
Drugs, Chinese Herbal/administration & dosage , Hypertension/drug therapy , Kidney Diseases/drug therapy , Medicine, Chinese Traditional , Nifedipine/administration & dosage , Splenic Diseases/drug therapy , Yang Deficiency/drug therapy , Aged , Drug Therapy, Combination , Female , Humans , Male
4.
Zhongguo Zhen Jiu ; 29(4): 299-301, 2009 Apr.
Article in Chinese | MEDLINE | ID: mdl-19565739

ABSTRACT

Professor Feng Run-Shen is engaged in medicine for more than 60 years. He pays attention to medical ethics and has perfect medical skill. He energetically advocates combination of acupuncture with medication and stresses the concept of viewing the situation as a whole in selection of acupoints and treatment, particularly, clinical application of point properties. Clinically, he is accomplished in penetration needling, for which one needle acts on two or more points, enlarging the range of needling sensation, so it has very good therapeutic effects on many diseases. In the paper, the case samples about penetration needling in his clinical practice are summarized and introduced.


Subject(s)
Acupuncture Points , Acupuncture Therapy/methods , Needles , Acupuncture/instrumentation , Acupuncture/methods , Acupuncture Therapy/instrumentation , Adult , Arthralgia/therapy , Child, Preschool , Diarrhea , Dizziness/therapy , Female , Humans , Knee Joint/pathology , Male , Middle Aged , Treatment Outcome
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