Triptriolide

Triptriolide antagonizes triptolide-induced nephrocyte apoptosis via inhibiting oxidative stress in vitro and in vivo.[Pubmed:31369987]

Biomed Pharmacother. 2019 Oct;118:109232.

Triptolide(T9) is a predominant bioactive component extracted from Chinese herb Tripterygium wilfordii Hook F. (TwHF), and has multiple pharmacological activities, such as immunosuppressive and anti-inflammatory activities, et al. However, severe adverse effects and toxicity, particularly nephrotoxicity, limit its clinical application. It has been demonstrated that the activation of nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway could alleviate T9-induced nephrocyte damage. The aim of this study was to investigate the potential protective role of Triptriolide (T11) against T9-induced nephrocyte apoptosis in vitro and in vivo. Renal injury models were established in human kidney 2 (HK2) cells and BALB/c mice using T9, and the protective effects of T11 were probed in vitro and in vivo, respectively. T9 induced nephrocyte damage in HK2 cells and BALB/c mice by induction of reactive oxygen species (ROS), lactate dehydrogenase (LDH), malondialdehyde (MDA) and glutathione (GSH) and reduction of superoxide dismutase (SOD), which resulted in the apoptosis of nephrocyte and injury of renal function. While, pretreatment of T11 effectively reversed these changes, resulting in the obvious decrease of oxidative stress and renal function parameters, ameliorated nephrocyte apoptosis, improved cell morphology, and higher increase of Nrf2, NAD(P)H: quinine oxidoreductase 1 (NQO1) and heme oxygenase 1 (HO-1) protein levels in vitro and in vivo. Altogether, T11 protected against T9-induced nephrocyte apoptosis possibly via suppressing oxidative stress.

Tripterygium glycoside fraction n2: Alleviation of DSS-induced colitis by modulating immune homeostasis in mice.[Pubmed:30851581]

Phytomedicine. 2019 May;58:152855.

BACKGROUND: The Tripterygium glycosides (TG) is the main active extractive of Tripterygium wilfordii Hook F and is widely used in clinical practice to treat inflammatory diseases (including inflammatory bowel disease). However, due to its severe toxicity, TG is restricted to the treatment of many diseases. Therefore, it is necessary to study a new method to obtain the attenuated and synergistic extracts from TG. PURPOSE: Tripterygium glycosides-n2 (TG-n2) was obtained from TG by a new preparation method. In this study, we aimed to investigate the difference in the chemical compositions between TG and TG-n2, further explored its toxicity and therapeutic effects on DSS-induced colitis in mice. METHODS: The major chemical compositions of TG and TG-n2 were analyzed by ultra-performance liquid chromatography (UPLC). Subsequently, acute toxicity test was applied to evaluate the toxicity difference between TG and TG-n2. Dextran sulfate sodium (DSS)-induced acute colitis model was used to explore the therapeutic effect of TG and TG-n2 and their potential mechanisms of action. RESULTS: We found that the chemical compositions of TG-n2 is different from TG. The main difference is the ratio of Triptriolide (T11) / triptolide (T9). Acute toxicity test proved that TG-n2 was less toxic than TG. Base on this, further studies showed that TG-n2 has a similar therapeutic effect as compared to TG on attenuating the symptoms of colitis, such as diarrhea, bloody stools, body weight loss, colonic atrophy, histopathological changes, inhibiting cytokines secretion and reducing absolute lymph number. In addition, TG and TG-n2 can increase the apoptosis of T lymphocyte in vivo. Further investigated showed that TG and TG-n2 could increase the expressions of Bax and p62 on CD3-positive T cells. CONCLUSION: This study showed that oral administration of TG-n2 is safer than TG. Moreover, the attenuated TG-n2 has the similar therapeutic effect on treating experimental colitis in mice when compared to TG. Its mechanism may be related to activating the expression of Bax in T cells and inducing T cells autophagy to regulate the survival of T lymphocytes in colitis mice, thus reducing inflammation in colon.

Dual-function of triptriolide in podocytes injury: inhibiting of apoptosis and restoring of survival.[Pubmed:30551448]

Biomed Pharmacother. 2019 Jan;109:1932-1939.

Triptriolide (T11) is a natural diterpene diepoxide that derived from Chinese traditional herb medicine (TCHM) Tripterygium wilfordii Hook.F (TWHF). From a structural point of view, T11 is very similar to triptolide (T9), one of the most effectively compounds in TWHF that have already been systematically investigated in the past decades. However, the basic functions and medicinal properties of T11 have not yet been well investigated mainly due to its low abundance in its plant organ. The present study aimed to investigate the protective effects of T11 on puromycin aminonucleoside (PAN) induced apoptotic mouse podocytes and the underlying mechanism. The results showed that T11 had no significant toxicity in podocytes in high dosage, and showed prominent protective effects on PAN induced podocytes injury. Further studies indicated that T11 might exert its protective effects by inhibiting of apoptosis and restoring of survival in PAN induced podocytes.

Triptriolide Alleviates Lipopolysaccharide-Induced Liver Injury by Nrf2 and NF-kappaB Signaling Pathways.[Pubmed:30210350]

Front Pharmacol. 2018 Aug 29;9:999.

Nrf2 (Nuclear Factor Erythroid 2 Related Factor 2) transcription factor not only regulates oxidative stress response, but also represses inflammation by regulating cytokines production and cross-talking with NF-kappaB signaling pathways. Nrf2 plays an essential role in liver injury induced by oxidative stress and inflammation. Triptriolide (T11) is a minor component of Tripterygium wilfordii Hook F. (TwHF), which can be obtained by hydrolysis reaction of triptolide (T9). The major purpose of this study is to clarify the regulating effects of T11 on oxidative stress and inflammation in vivo and in vitro. LPS-stimulated RAW 264.7 cells were used to verify the regulating effects of T11 on oxidative stress (ROS and Nrf2 signaling pathway) and inflammatory cytokines production (TNF-alpha, IL-6 and IL-1beta). The antioxidant responsive element (ARE) luciferase assay was employed to evaluate Nrf2 activation effect of T11 in HEK-293T cells. Lipopolysaccharides (LPS) induced acute liver injury (ALI) in BALB/c mice were used to study the protective effects (ALT, AST, MDA, SOD, histopathology and neutrophils/macrophages filtration) and the underlying protection mechanisms of ALI amelioration (Nrf2 and NF-kappaB signaling pathway) of T11. Firstly, the results showed that T11 can not only effectively decrease the productions of inflammatory cytokines (TNF-alpha, IL-6 and IL-1beta), ROS and NO in LPS-stimulated RAW 264.7 cells, but also further significantly increase the activity of Nrf2 in HEK-293T cells. Secondly, the results suggested that T11 could dramatically decrease the oxidative stress responses (SOD and MDA) and inflammation (histopathology, neutrophils/macrophages filtration, TNF-alpha, IL-6 and IL-1beta production) in LPS-induced ALI in BALB/c mice. Finally, the results implied that T11 could dramatically increase Nrf2 protein expression and decrease p-TAK1, p-IkappaBalpha and NF-kappaB protein expression both in vivo and in vitro. In conclusion, our findings indicated that T11 could alleviate LPS induced oxidative stress and inflammation by regulating Nrf2 and NF-kappaB signaling pathways in vitro and in vivo, which offers a novel insights for the application of TwHF in clinical.

Biotransformation of triptolide and triptonide by cell suspension cultures of Catharanthus roseus.[Pubmed:15008455]

J Asian Nat Prod Res. 2004 Jun;6(2):93-7.

Catharanthus roseus cell suspension cultures were used to bioconvert both triptolide (1) and triptonide (2). The same reaction path was followed in both biotransformations. Two biotransformed products were obtained and their structures identified as Triptriolide (3) and 12beta,13alpha-dihydroxytriptonide (4), respectively, from 1 and 2. Product 4 is a new compound.

Analysis of the stability and degradation products of triptolide.[Pubmed:10716597]

J Pharm Pharmacol. 2000 Jan;52(1):3-12.

Triptolide is the major active ingredient of the Chinese herbal remedy Tripterygium wilfordii Hook F. (TwHF). As triptolide content is used to estimate the potency of preparations of TwHF, assessment of its stability is warranted. The accelerated stability of triptolide was investigated in 5% ethanol solution in a light-protected environment at pH 6.9, within a temperature range of 60-90 degrees C. The observed degradation rate followed first-order kinetics. The degradation rate constant (K25 degrees C) obtained by trending line analysis of Arrhenius plots of triptolide was 1.4125 x 10(-4) h(-1). The times to degrade 10% (t1/10) and 50% (t1/2) at 25 degrees C were 31 and 204 days, respectively. Stability tests of triptolide in different solvents and different pH conditions (pH4-10) in a light-protected environment at room temperature demonstrated that basic medium and a hydrophilic solvent were the major factors that accelerated the degradation of triptolide. Triptolide exhibited the fastest degradation rate at pH 10 and the slowest rate at pH 6. In a solvent comparison, triptolide was found to be very stable in chloroform. The stability of triptolide in organic polar solvents tested at both 100% and 90% concentration was greater in ethanol than in methanol than in dimethylsulphoxide. Stability was also greater in a mixture of solvent:pH6 buffer (9:1) than in 100% solvent alone. An exception was ethyl acetate, which is less polar than the other solvents tested, but permitted more rapid degradation of triptolide. Two of the degradation products of triptolide were isolated and identified by HPLC and mass spectroscopy as Triptriolide and triptonide. This suggested that the decomposition of triptolide occurred at the C12 and C13 epoxy group and the C14 hydroxyl. The opening of the C12 and C13 epoxy is an irreversible reaction, but the reaction occurring on the C14 hydroxyl is reversible. These results show that the major degradation pathway of triptolide involves decomposition of the C12 and C13 epoxy group. Since this reaction is very slow at 4 degrees C at pH 6, stability is enhanced under these conditions.

[Studies on diterpenoids from leaves of Tripterygium wilfordii].[Pubmed:8328278]

Yao Xue Xue Bao. 1993;28(2):110-5.

Tripterygium wilfordii Hook f. has been used as a medicinal herb in traditional Chinese medicine and as an insecticide by the Chinese for hundreds of years. Recently, this plant has been used to treat cancer, rheumatic arthritis and various skin diseases in some Chinese clinics. It is of interest to note that Tripterygium also showed significant antifertility activities. The active principles of the anti-inflammatory, immunosuppressive and antifertile actions in Tripterygium are diterpenoid containing triepoxides, but information on its chemistry is limited to the woody part of the root and the root bark. Recently, we have studies the leaves of Tripterygium (collected at Zhejiang province, China), and isolated two novel diterpenoids by chromatography named tripdioltonide (8) and 13,14-epoxide 9,11,12-trihydroxytriptolide (9), besides triptonide (1), triptolide (2), tripdiolide (3), triptolidenol (4), 16-hydroxyl-triptolide (5), tripchlorolide (6) and Triptriolide (7). Their structures were established by chemical reactions, TLC, UV, MS, IR, 1H-1H COSY, 1H-13C COSY, DEPT spectrometric investigation. The structure of tripdioltonide was further confirmed by X-ray analysis.

[Screening of active anti-inflammatory, immunosuppressive and antifertility components of Tripterygium wilfordii. III. A comparison of the antiinflammatory and immunosuppressive activities of 7 diterpene lactone epoxide compounds in vivo].[Pubmed:1838954]

Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 1991 Dec;13(6):391-7.

The half-effective dose(ED50), therapeutic index(TI) and certain safety factor(CSF) of 7 diterpene lactone epoxide compounds with antiinflammatory and immunosuppressive action extracted from Tripterygium wilfordii (TW) were assayed using croton oil-induced ear swelling and hemolysin-antibody formation mouse models. The results indicated that triptolide(T10), tripchlorolide(T4), triptonide(T7), tripdiolide(T8), triptolidenol(T9) and 16-hydroxytriptolide(L2) possessed both anti-inflammatory and immunosuppressive activities, while Triptriolide(T11) had antiinflammatory activity only. The TI of the antiinflammatory action of 7 compounds were arranged in following order: T11(greater than 19), T10(17), T9(9.6), T4(9.0), T8(7.3), L2(6.6), T7(5.9), while the TI of the immunosuppressive action of 6 compounds were arranged in following order: T9(30.7), T4(16.7), L2(15.8), T10(13.7), T8(8.8), T7(7.5). The CSF parameters of both the activities of 7 compounds were all higher than 1. In which, the CSF of the immunosuppressive action of T9, T4 and L2 were 7.1, 5.1 and 3.6 respectively. These facts clearly demonstrate that the antiinflammatory and immunosuppressive compounds in TW are pluralistic. These differences among these compounds can be used as one of the bases for the evaluation and selection of these compounds. The above experiments conclude that the practical value of these compounds, however, will also depend on their content and yield rate in the herb, on the degree of difficulty in synthesizing these compounds, and on difficulty involved in the preparation of their derivatives. The future of these compounds will depend on the results of genetic toxicology studies as well.