Isolation and identification of bioactive compounds in Andrographis paniculata (Chuanxinlian)

Anti-scorpion venom activity of Andrographis paniculata: A combined and comparative study with anti-scorpion serum in mice

OBJECTIVES

The objective of this study is to evaluate the anti-scorpion venom (ASV) property of Andrographis paniculata in comparison with anti-redscorpion venom serum and this study aimed to determine its combined effect with anti-redscorpion venom serum.

MATERIALS AND METHODS

Ethanolic extract of the plant AP was obtained using soxhlet apparatus. Swiss albino mice weighing 20-30g were used. Lyophilized venom sample of Mesobuthus tamulus and Lyophilized monovalent enzyme refined immunoglobulin anti-scorpion venom serum (ASV) was used. Using lethal dose of scorpion venom (25.12μg/g), the venom neutralizing ability of plant extract (1 g/kg) and ASV individually as well as in combination was studied using in vivo and in vitro methods. Mean survival time, protection fold and percentage survival of animals over the period of 24 h were the parameters used.

STATISTICAL ANALYSIS

Results were analyzed using Student's t-test.

RESULTS

Ethanolic extract of AP (1 g/kg) showed some protective effect against scorpion venom. ASV was found more effective than plant extract. But, when plant extract and ASV were used in combination, potency of ASV was found to be increased both in vivo and in vitro.

CONCLUSIONS

Present study demonstrates that, both plant extract and ASV have their own scorpion venom neutralising ability in vivo and in vitro, but their combination is most effective in venom neutralizing ability.

Pancreatic effect of andrographolide isolated from Andrographis paniculata (Burm. f.) Nees

Andrographis paniculata (Burm. f.) Nees is a plant that originates from India and grows widely to Southeast which used for several purposes mainly as treatment of diabetes mellitus so the aim of this study was evaluate andrographolide for its pancreatic effect in neonatal streptozotocin (STZ)-induced diabetic rats, a model of type 2 diabetic rats. Diabetic condition was induced with an intraperitoneal injection of 90 mg kg(-1) streptozotocin in two-day-old rats. After three months, the neonatal STZ-induced diabetic rats were treated with andrographolide or andrographolide-enriched extract of A. paniculata (AEEAP) for 8 consecutive days. Pancreatic effect was evaluated by estimating mainly the preprandial and postprandial blood glucose levels and other parameters such as morphology of pancreatic islet, beta cells density and morphology and immunohistochemically pancreatic insulin. Andrographolide significantly (p < 0.05) decreased the levels of blood glucose and improved diabetic rat islet and beta cells. However, AEEAP exhibited moderate hypoglycaemic effects on the blood glucose levels. Moderate changes in beta cells were observed after AEEAP treatment. They could restore decreasing of pancreatic insulin contents. Based on these results andrographolide and AEEAP exhibited pancreatic actions in neonatal STZ-induced diabetic rats. The activity of andrographolide was more effective than this of AEEAP.

Andrographis paniculata Extract and Andrographolide Modulate the Hepatic Drug Metabolism System and Plasma Tolbutamide Concentrations in Rats

Andrographolide is the most abundant terpenoid of A. paniculata which is used in the treatment of diabetes. In this study, we investigated the effects of A. paniculata extract (APE) and andrographolide on the expression of drug-metabolizing enzymes in rat liver and determined whether modulation of these enzymes changed the pharmacokinetics of tolbutamide. Rats were intragastrically dosed with 2 g/kg/day APE or 50 mg/kg/day andrographolide for 5 days before a dose of 20 mg/kg tolbutamide was given. APE and andrographolide reduced the AUC_0–12 h of tolbutamide by 37% and 18%, respectively, compared with that in controls. The protein and mRNA levels and enzyme activities of CYP2C6/11, CYP1A1/2, and CYP3A1/2 were increased by APE and andrographolide. To evaluate whether APE or andrographolide affected the hypoglycemic action of tolbutamide, high-fat diet-induced obese mice were used and treated in the same manner as the rats. APE and andrographolide increased CYP2C6/11 expression and decreased plasma tolbutamide levels. In a glucose tolerance test, however, the hypoglycemic effect of tolbutamide was not changed by APE or andrographolide. These results suggest that APE and andrographolide accelerate the metabolism rate of tolbutamide through increased expression and activity of drug-metabolizing enzymes. APE and andrographolide, however, do not impair the hypoglycemic effect of tolbutamide.

Time course changes of anti- and pro-apoptotic proteins in apigenin-induced genotoxicity

Background

Apigenin (4′,5,7-trihydroxyflavone, AP), an active component of many medicinal Chinese herbs, exhibits anticancer properties in vitro and in vivo. This study aims to investigate the genotoxic, cytostatic, and cytotoxic effects of AP and time course changes in the levels of anti- and pro-apoptotic proteins involved in the DNA damage response in HepG2 cells.

Methods

The genotoxic potential of AP was determined by sister chromatid exchanges (SCEs) and chromosomal aberrations (CAs) analysis. The levels of cytostaticity and cytotoxicity were evaluated by the proliferation rate and mitotic indices, respectively. MTT was used to study cytotoxicity, while the induction of apoptosis and the expression of apoptosis-related proteins were determined by ELISA.

Results

At concentrations greater than 10 μM, AP decreased cell survival in a dose- (48 h: 10 vs. 20 μΜ, P < 0.001 and 20 vs. 50 μΜ, P = 0.005; 72 h: 10 vs. 20 μΜ, P < 0.001 and 20 vs. 50 μΜ, P = 0.001) and time-dependent manner (20 μΜ: 24 vs. 48 h, P < 0.001 and 48 vs. 72 h, P = 0.003; 50 μΜ: 24 vs. 48 h, P < 0.001 and 48 vs. 72 h, P < 0.001; 100 μΜ: 24 vs. 48 h, P < 0.001 and 48 vs. 72 h, P < 0.001). SCEs rates, cell proliferation, and mitotic divisions were also affected in a dose-dependent manner (P < 0.001). There was no change in the frequency of aberrant cells (1 μΜ ΑP: P = 0.554; 10 μM AP: P = 0.337; 20 μΜ AP: P = 0.239). Bcl-2 levels were reduced 3 h after AP administration (P = 0.003) and remained reduced throughout the 48 h observation period (6 h, P = 0.044; 12 h, P = 0.001; 24 h, P = 0.042; 48 h, P = 0.012). Bax and soluble Fas exhibited a transient upregulation 24 h after AP treatment. The Bax/Bcl-2 ratio was also increased at 12 h and remained increased throughout the 48 h observation period.

Conclusion

AP exhibited dose-dependent genotoxic potential in HepG2 cells. The protein levels of sFas, Bcl-2, and Bax were affected by AP to promote cell survival and cell death, respectively.

Changes in the contents of four active diterpenoids at different growth stages in Andrographis paniculata (Burm.f.) Nees (Chuanxinlian)

Background

The therapeutic activities of Andrographis paniculata are attributed to four major active diterpenoids: andrographolide (AP₁), 14-deoxy-11,12-didehydroandrographolide (AP₃), neoandrographolide (AP₄), and 14-deoxyandrographolide (AP₆). This study aims to quantify the four active diterpenoids in various plant organs of A. paniculata at different growth stages in greenhouse and field experiments, with a developed HPLC-diode array detector (HPLC-DAD) method for simultaneous determination of these diterpenoids.

Methods

Plants were grown in greenhouse and in field conditions, harvested at different growth stages, and separated into different organs for determination of the four active diterpenoids by an HPLC-DAD method.

Results

The most abundant diterpenoid was AP₆ between seedling and vegetative stages in the greenhouse experiment (13.38 to 23.71 mg/g in 2006 and 10.67 to 24.54 mg/g in 2007). High levels of AP₆ were also detected in leaves at the transfer stage in the greenhouse experiment (36.05 ± 0.69 mg/g) and field experiment (30.59 ± 1.39 mg/g). The levels of AP₆ then decreased as plants matured. The highest content of AP₄ was in cotyledons (16.65 ± 4.48 mg/g) at the transfer stage. The highest contents of AP₁ were detected in leaves at seed-forming stage in greenhouse experiment (24.72 ± 1.89 mg/g) and vegetative stage in field experiment (43.16 ± 0.92 mg/g). Flowers of A. paniculata contained high levels of AP₁ (21.42 ± 3.74 mg/g). AP₃ and AP₄ were at low levels in leaves at all growth stages.

Conclusion

In A. paniculata, AP₆ was at the highest level in leaves at transfer stage in both greenhouse and field experiments. AP₁ was at the highest level in leaves at vegetative stage and seed-forming stage in field and greenhouse experiments, respectively. The contents of AP₃ and AP₄ in leaves were low at all growth stages.

Andrographolide and its analogues: versatile bioactive molecules for combating inflammation and cancer

1. Andrographis paniculata (Burm. f) Nees, commonly known as 'king of bitters', is a herbaceous plant belonging to the Family Acanthaceae. It has been widely used for centuries in Asian countries like China, India, Thailand and Malaysia for the treatment of sore throat, flu and upper respiratory tract infections. 2. Andrographolide, 14-deoxy-11,12-didehydroandrographolide and neoandrographolide are examples of the major labdane diterpenoids isolated from A. paniculata. These bioactive molecules have exhibited varying degrees of anti-inflammatory and anticancer activities in both in vitro and in vivo experimental models of inflammation and cancer. 3. Extensive libraries of andrographolide analogues have been synthesised mainly by modifying the α,β-unsaturated γ-butyrolactone moiety, the two double bonds Δ(8,(17)) and Δ(12,(13)) and the three hydroxyls at C-3 (secondary), C-14 (allylic) and C-19 (primary). Many of these synthetic analogues exhibit superior anticancer activity over the naturally occurring andrographolides. 4. Andrographolide and its derivatives have been shown to have anti-inflammatory effects in experimental models of asthma, stroke and arthritis, as well as in patients with upper respiratory tract infections. Andrographolide reduces the production of cytokines, chemokines, adhesion molecules, nitric oxide and lipid mediators, probably via inhibition of the nuclear factor (NF)-κB signalling pathway. 5. The anticancer mechanisms for andrographolide include inhibition of Janus tyrosine kinases-signal transducers and activators of transcription, phosphatidylinositol 3-kinase and NF-κB signalling pathways, suppression of heat shock protein 90, cyclins and cyclin-dependent kinases, metalloproteinases and growth factors, and the induction of tumour suppressor proteins p53 and p21, leading to inhibition of cancer cell proliferation, survival, metastasis and angiogenesis. 6. Andrographolide drug discovery is a promising strategy for the development of a novel class of anti-inflammatory and anticancer drugs.

Pharmacokinetics and tolerance of dehydroandrographolide succinate injection after intravenous administration in healthy Chinese volunteers

AIM

Dehydroandrographolide succinate (DAS) is extracted from herbal medicine Andrographis paniculata (Burm f) Nees. DAS injection is used in China for the treatment of viral pneumonia and upper respiratory tract infections. The aim of this study is to investigate the pharmacokinetics and tolerance of DAS injection in healthy Chinese volunteers.

METHODS

This was a single-center, randomized, single-dose, three-way crossover design study. Nine eligible subjects were randomly divided into 3 groups, and each group sequentially received 80, 160, or 320 mg of DAS infusion according to a three-way Latin square design. Plasma and urine samples were collected and determined using an LC-MS/MS method. Safety and tolerability were determined via clinical evaluation and adverse event monitoring.

RESULTS

For the 80, 160, and 320 mg dose groups, the mean C(max) were 4.82, 12.85, and 26.90 mg/L, respectively, and the mean AUC(0-12) were 6.18, 16.95, and 40.65 mg·L(-1)·h, respectively. DAS was rapidly cleared, with a mean T(max) of 0.94-1.0 h and a t(1/2) of approximately 1.51-1.89 h. Approximately 10.1%-15.5% of the intravenous DAS dose was excreted unchanged in urine within 24 h in the 3 groups, and more than 90% of unchanged DAS was excreted between 0 and 4 h. The pharmacokinetic profile was similar between male and female subjects. No serious or unexpected adverse events were found during the study, but one mild adverse event (stomachache) was reported.

CONCLUSION

This study shows that DAS has nonlinear pharmacokinetic characteristics. To guarantee the effective concentration, mul¬tiple small doses are recommended in clinical regimens.

Antidiabetic and antihiperlipidemic effect of Andrographis paniculata (Burm. f.) Nees and andrographolide in high-fructose-fat-fed rats

Objectives:

Andrographis paniculata (Burm. f.) Nees originates from India and grows widely in many areas in Southeast Asian countries. Andrographis paniculata (Burm. f.) Nees has shown an antidiabetic effect in type 1 DM rats. The present study investigates the purified extract of the plant and its active compound andrographolide for antidiabetic and antihyperlipidemic effects in high-fructose-fat-fed rats, a model of type 2 DM rats.

Materials and Methods:

Hyperglycemia in rats was induced by high-fructose-fat diet containing 36% fructose, 15% lard, and 5% egg yolks in 0.36 g/200 gb.wt. 55 days. The rats were treated with the extract or test compound on the 50^th day. Antidiabetic activity was measured by estimating mainly the pre– and postprandial blood glucose levels and other parameters such as cholesterol, LDL, triglyceride, and body weight.

Results:

The purified extract and andrographolide significantly (P<0.05) decreased the levels of blood glucose, triglyceride, and LDL compared to controls. However, no changes were observed in serum cholesterol and rat body weight. Metformin also showed similar effects on these parameters.

Conclusions:

Andrographis paniculata (Burm. f.) Nees or its active compound andrographolide showed hypoglycemic and hypolipidemic effects in high-fat-fructose-fed rat.

Modifications of andrographolide to increase some biological activities: a patent review (2006 - 2011)

INTRODUCTION

Andrographis paniculata Nees, Acanthaceae, is a well-recognised medicinal plant in Asia. It has been reported to possess a variety of biological activities. The main constituent of A. paniculata is andrographolide (Androg). Since the plant is known to treat many diseases, Androg was modified for many biological activities to treat and prevent a variety of diseases.

AREA COVERED

This review surveys the patents from 2006 to 15 November 2011 for antibacterials, antivirals, antidiabetic, anticancer, analgesic, antipyretic and anti-inflammatory analogues. SciFinder database was used to search for the patent work using the keywords 'andrographolide', 'andrographolide derivatives', 'andrographolide analogues' and later additional limits, that is, 'patent' and 'years', 'Clinical trial' and 'years' were searched. Espacenet was also searched for 'andrographolide', 'andrographolide derivatives' and 'andrographolide analogues'.

EXPERT OPINION

Androg is a good pharmacophore for many pharmacological activities. Esterification at either one or more of the three hydroxyls with short/long chains, heterocyclic, aromatic fatty acids was attempted and tested for a variety of activities. Most of the responses were positive. Other modifications were epoxidation at Δ(7(18)) along with esterifications with various carboxylic acids for anticancer activity. 15-Alkylidene analogues were investigated for α-glucosidase inhibition. The improvement of activities have not yet been proven to be due to the increase in the ability of analogues to reach the targets as prodrugs or the new feature structures fitted to the receptors. It seems that substitution with active compounds, such as lipoic acid, is a new trend for modification.

Screening of anti-dengue activity in methanolic extracts of medicinal plants

Background

Dengue fever regardless of its serotypes has been the most prevalent arthropod-borne viral diseases among the world population. The development of a dengue vaccine is complicated by the antibody-dependent enhancement effect. Thus, the development of a plant-based antiviral preparation promises a more potential alternative in combating dengue disease.

Methods

Present studies investigated the antiviral effects of standardised methanolic extracts of Andrographis paniculata, Citrus limon, Cymbopogon citratus, Momordica charantia, Ocimum sanctum and Pelargonium citrosum on dengue virus serotype 1 (DENV-1).

Results

O. sanctum contained 88.6% of total flavonoids content, an amount that was the highest among all the six plants tested while the least was detected in M. charantia. In this study, the maximum non-toxic dose (MNTD) of the six medicinal plants was determined by testing the methanolic extracts against Vero E6 cells in vitro. Studies also determined that the MNTD of methanolic extract was in the decreasing order of M. charantia >C. limon >P. citrosum, O. sanctum >A. paniculata >C. citratus. Antiviral assay based on cytopathic effects (CPE) denoted by degree of inhibition upon treating DENV1-infected Vero E6 cells with MNTD of six medicinal plants showed that A. paniculata has the most antiviral inhibitory effects followed by M. charantia. These results were further verified with an in vitro inhibition assay using MTT, in which 113.0% and 98.0% of cell viability were recorded as opposed to 44.6% in DENV-1 infected cells. Although methanolic extracts of O. sanctum and C. citratus showed slight inhibition effect based on CPE, a significant inhibition was not reflected in MTT assay. Methanolic extracts of C. limon and P. citrosum did not prevent cytopathic effects or cell death from DENV-1.

Conclusions

The methanol extracts of A. paniculata and M. charantia possess the ability of inhibiting the activity of DENV-1 in in vitro assays. Both of these plants are worth to be further investigated and might be advantageous as an alternative for dengue treatment.

The cardioprotective effects of marrubiin, a diterpenoid found in Leonotis leonurus extracts

ETHNOPHARMACOLOGICAL RELEVANCE

Leonotis leonurus L. (Lamiaceae) is used as a traditional medicine for a variety of ailments in South Africa. The diterpene marrubiin is the major product constituent in specimens of this plant occurring in South Africa.

MATERIALS AND METHODS

Marrubiin isolated from South African specimens of L. leonurus in addition to an organic extract of L. leonurus were tested in vivo, ex vivo and in vitro for their anticoagulant, antiplatelet and anti-inflammatory activities.

RESULTS

Marrubiin and the organic extract suppressed coagulation, platelet aggregation and inflammatory markers. For the coagulation markers it was found that the organic extract and marrubiin significantly prolonged activated partial thromboplastin time (APTT). Fibrin and D-dimer formation were drastically decreased. These findings were observed in an ex vivo model and an obese rat model. Chemokines enhance leukocyte recruitment to inflammatory sites. TNF-α and RANTES secretion were significantly reduced by the extract and marrubiin when determined in the obese rat model relative to the controls. Calcium mobilization and TXB(2) synthesis were suppressed by the extract and marrubiin. An in vitro model was used to elucidate the antiplatelet mechanism and it was found that the extract and marrubiin inhibited platelet aggregation by inhibiting the binding of fibrinogen to glycoprotein (GP) IIb/IIIa receptor in a concentration dependent manner.

CONCLUSION

The findings reflect that marrubiin largely contributes to the extract's anticoagulant, antiplatelet and anti-inflammatory effects observed.

Different AhR binding sites of diterpenoid ligands from Andrographis paniculata caused differential CYP1A1 induction in primary culture in mouse hepatocytes

Andrographis paniculata has been employed as a folklore remedy. Andrographolide (Andro), 14-deoxy-11,12-didehydroandrographolide (DHA), andrographiside (AS), and neoandrographolide (Neo), are major diterpenoids isolated from this plant. In the present study, influence of the four diterpenoids on CYP1A1 mRNA expression was investigated in primary cultured mouse hepatocytes. Additionally, binding of these compounds to aryl hydrocarbon receptor (AhR) was examined using molecular docking analysis to clarify mechanism of CYP1A1 induction. Andro and DHA induced CYP1A1 expression by itself, and co-treatment with a CYP1A1 inducer (BNF, beta-naphthoflavone) showed a synergistic increase of CYP1A1 expression. Andro demonstrated higher enhancing activity than DHA at every similar concentration. On the other hand, Neo suppressed BNF-induced CYP1A1 expression, but AS did not modify the induction. Results from molecular docking analysis of BNF and four diterpenoids on ligand binding domain of AhR were consistent with levels of CYP1A1 mRNA expressions. Furthermore, difference of binding sites of BNF in the presence of diterpenoids might affect the synergism or inhibition of CYP1A1 expression. These results suggest that use of A. paniculata as a health supplement should be concerned in term of herb-drugs interactions or risk of carcinogenesis, according to its ability to influence CYP1A1 expression.

Proteomic alterations in mouse kidney induced by andrographolide sodium bisulfite

AIM

To identify the key proteins involved in the nephrotoxicity induced by andrographolide sodium bisulfite (ASB).

METHODS

Male ICR mice were intravenously administrated with ASB (1000 or 150 mg·kg⁻¹·d⁻¹) for 7 d. The level of malondialdehyde (MDA) and the specific activity of superoxide dismutase (SOD) in kidneys were measured. The renal homogenates were separated by two-dimensional electrophoresis, and the differential protein spots were identified using a matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF)/TOF mass spectrometry.

RESULTS

The high dose (1000 mg/kg) of ASB significantly increased the MDA content, but decreased the SOD activity as compared to the control mice. The proteomic analysis revealed that 6 proteins were differentially expressed in the high-dose group. Two stress-responsive proteins, ie heat shock cognate 71 kDa protein (HSC70) and peroxiredoxin-6 (PRDX6), were regulated at the expression level. The remaining 4 proteins involving in cellular energy metabolism, including isoforms of methylmalonyl-coenzyme A mutase (MUT), nucleoside diphosphate-linked moiety X motif 19 (Nudix motif19), mitochondrial NADH dehydrogenase 1 alpha subcomplex subunit 10 (NDUFA10) and nucleoside diphosphate kinase B (NDK B), were modified at the post-translational levels.

CONCLUSION

Our findings suggest that the mitochondrion is the primary target of ASB and that ASB-induced nephrotoxicity results from oxidative stress mediated by superoxide produced by complex I.