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Antihypertensive effects of oriental drugs in human and SHR
Published in H. Saito, Y. Yamori, M. Minami, S.H. Parvez, New Advances in SHR Research –, 2020
Hideaki Higashino, Aritomo Suzuki, Koichiro Komai
Uncaria rhynchophylla (Miq.) Jacks. (ref.A, 1990; ref.18a. 1960; ref.18b, 1960). Oral administration of the decoction of the stem with hooks showed a hypotensive action in anesthetized dogs (0.05 g/kg), rabbits (2-3 g/kg) and rats (5 g/kg). Since this action was not influenced by atropine treatment and the decoction has never caused direct vasodilation in the isolated ear arteries of rabbits, it was considered that this hypotensive action was caused by the inhibition of vasomotor center through the vagus. Although main component, rhynchophylline, reduced the blood pressure like as total alkaloid solution, the effect was much smaller and shorter than that of reserpine.
Herbal and Supplement Use in Pain Management
Published in Sahar Swidan, Matthew Bennett, Advanced Therapeutics in Pain Medicine, 2020
Drug interactions: Anticoagulant/antiplatelet drugs: cat’s claw contains rhynchophylline and isorhynchophylline. Research suggests that concurrent use of cat’s claw and anticoagulant/antiplatelet drugs can reduce platelet aggregation and cause an increased risk of bleeding in some patients.6Antihypertensive drugs: cat’s claw contains rhynchophylline and isorhynchophylline. Concurrent use of cat’s claw and antihypertensive drugs may increase the risk of hypotension.7Calcium channel blockers “moderate risk”: animal research suggests that the various alkaloids in cat’s claw can lower blood pressure by acting as a calcium channel blocker—(TRC Natural Medicines).CYP P450 3A4 substrates: cat’s claw inhibits 3A4 and may increase levels of drugs metabolized by CYP3A4, including ketoconazole, itraconzole, fexofenadine, and triazolam.8Immunosuppressants: cat’s claw may interfere with immunosuppressants due to the immunostimulating activity of cat’s claw. It stimulates phagocytosis and increases respiratory cellular activity and the mobility of leukocytes.3Protease Inhibitors: cat’s claw may increase levels of protease inhibitors because cat’s claw inhibits CYP 3A4. Use with caution.9
Inhibiting Low-Density Lipoproteins Intimal Deposition and Preserving Nitric Oxide Function in the Vascular System
Published in Christophe Wiart, Medicinal Plants in Asia for Metabolic Syndrome, 2017
Rhynchophylline inhibited the aggregation of platelets challenged with arachidonic acid, collagen, and adenosine diphosphate. Given intravenously at a dose of 20 mg/kg this alkaloid protected rodents against thrombosis.284 This oxindole alkaloid at 100 µM abrogated the contraction of endothelium-denuded human mesenteric arteries exposed to potassium via inhibition of influx of extracellular calcium via L-type calcium channel.285 Isorhynchophylline given prophylaxycally at a dose of 30 mg/kg to Guinea pigs inhibited ouabain-induced ventricular contraction.286 Furthermore, this alkaloid at a dose of 30 mg/kg to Wistar rats poisoned with intravenous injection of calcium chloride delayed the onset time and decreased the duration of ventricular arrhythmia and reduced mortality rate by 59%.286 In line, this alkaloid at 30 µM reduced cardiac calcium currents and action potential duration in isolated Guine pig ventricular cells and isolated rat cardiomyocytes.286 Isorhynchophylline from Uncaria rhynchophylla (Miq.) Miq. ex Havil. protected rats against monocrotaline, induced increase in right ventricle systolic pressure. It decreased right ventricular hypertrophy, and reduced the number of fully muscularized small arterioles via inhibition of pulmonary arterial smooth muscle cells proliferation.287In vitro this oxindole alkaloid inhibited the proliferation of human pulmonary arterial smooth muscle cells induced by platelet derived growth factor by preventing cyclin D1 and CDK6 expression and inducing the expression of p27Kip1.287 Further, this oxindole alkaloid inhibited the phosphorylation of platelet-derived growth factor receptor, and subsequent activation of Akt and glycogen synthase kinase-3 and inhibited the activation of extracellular signal-regulated kinase-1/2 and STAT3.287 Hirsutine from this plant at a concentration of 10 µM increased the viability of neonatal rat cardiomyocytes cultured under oxygen deprivation from approximately 40% to 85.6%.288 This indole alkaloid evoked a decrease in lactate dehydrogenase.288 Furthermore, hirsutine reversed the decrease in superoxide dismutase and increase in malondialdehyde observed during hypoxia to values close to normoxic cells.288
An overview of spirooxindole as a promising scaffold for novel drug discovery
Published in Expert Opinion on Drug Discovery, 2020
Li-Ming Zhou, Ren-Yu Qu, Guang-Fu Yang
Horsfiline, Coerulescine, and Elacomine are the simplest compounds with tricyclic spirooxindoles, which were isolated from the roots of Horsfieldia superba, Phalaris coerulescens, and Elaeagnus commutate, respectively [7,8]. Spirobrassinin and its analog methoxyspirobrassinin, oxindole alkaloids containing dihydrothiazole, are a kind of plant antitoxins with promising bactericidal and antitumor activities [9]. Rhynchophylline is an N-methyl-D-aspartate receptor antagonist, which is regarded as a neuroprotective agent (such as antihypertensive, antipyretic, and anticonvulsant medicine) [10]. Strychnofoline can effectively inhibit mitosis of multiple cells, thereby displaying potent inhibitory effects against melanoma and Ehrlich tumor cells [11]. Spindomycin B is a spirooxindole derivative isolated from Streptomyces sp. xzqh-9, which exhibits weak inhibition toward tyrosine kinase Bcr-Abl (Philadelphia chromosome) [12].
Stereoselective in vitro metabolism of rhynchophylline and isorhynchophylline epimers of Uncaria rhynchophylla in rat liver microsomes
Published in Xenobiotica, 2018
Xin Wang, Zhou Qiao, Jia Liu, Mei Zheng, Wenyuan Liu, Chunyong Wu
Uncaria rhynchophylla (Miq.) Miq. ex Havil. (UR; family Rubiaceae), Gou-Teng in Chinese, is a traditional medicinal plant which has been widely used in Asia, Africa and America for centuries to treat vascular and neurodegenerative diseases (Zhang et al. 2015). Alkaloids, especially tetracyclic monoterpenoid oxindole alkaloids (TMOAs), are reported to be the major components and bioactive constituents in UR (Xie et al. 2013). Among them, rhynchophylline (RIN) and isorhynchophylline (IRN), accounting for 28%-50% and 15% of total alkaloids in UR, respectively, are the most abundant and characteristic compounds which showed effective neuroprotective activity (Ng et al. 2015; Zhou & Zhou 2010). Recently, accumulating evidence proved that RIN and IRN are potential anti-Alzheimer’s disease agents via multiple ways, such as preventing β-amyloid (Aβ) fibril formation, reducing neuronal apoptosis, and inhibiting the receptor tyrosine kinase EphA4 (Fu et al. 2014; Xian et al. 2012; Xian et al. 2014). Additionally, IRN could notably stimulate autophagy and promote pathogenic protein aggregates in neurons (Lu et al. 2012). Therefore, these findings enhanced the possibility that TMOAs derivatives, especially RIN and IRN, might be developed as therapeutic agents to treat Alzheimer’s disease.
Phylogenetic analysis of Uncaria species based on internal transcribed spacer (ITS) region and ITS2 secondary structure
Published in Pharmaceutical Biology, 2018
Shuang Zhu, Qiwei Li, Shanchong Chen, Yesheng Wang, Lin Zhou, Changqing Zeng, Jun Dong
Ridsdale (1978) concluded that U. rhynchophylloides is the same species as U. rhynchophylla even though they appear morphologically distinct (Wang et al. 2007) and have different chemical constituents. U. rhynchophylloides has a high proportion of hirsutine but very low content of rhynchophylline and isorhynchophylline, which are important chemical compounds in medicinal Gouteng (Zhong and Feng 1996). In contrast, phylogenetic analysis in the present study showed that U. rhynchophylloides was not a synonym of U. rhynchophylla, as they were located far apart (Figure 2). On the other hand, U. rhynchophylloides was depicted as a separate clade and nested in U. lancifolia, which is highly similar to prior description of U. rhynchophylloides based on morphological characteristics (Wang et al. 2007), yet U. lancifolia did not cluster into a monophyletic clade in two trees. Similar branching patterns were also found between U. sessilifructus and U. laevigata (Figure 2), i.e., U. sessilifructus was clustered into a separate clade but U. laevigata failed to cluster into a monophyletic group. High nucleotide diversity may explain why U. lancifolia and U. laevigata were not monophyletic (Table 4).