Preliminary evaluation of In vitro and In vivo antioxidative and antitumor activities of flavonoid extract of Tabernaemontana divaricata leaves in Ehrlich's lymphoma and Dalton's lymphoma ascites model

Aims: In the present study, the flavonoid fraction of Tabernaemontana divaricata flavonoid fraction(TdFf) leaves was investigated for its in vitro and in vivo antioxidative and antitumor activity. Subjects and Methods: The flavonoid fraction of ethyl acetate extract was assessed for their in vitro antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), superoxide radicals, ferric reducing antioxidant power (FRAP), hydrogen peroxide, hydroxyl radicals and nitric oxide and in vivo antioxidative activity by enzymic and nonenzymic antioxidants in the liver of intraperitoneally implanted Ehrlich's lymphoma (EAC) and Dalton's lymphoma ascites (DLAs) model. The in vitro cytotoxicity was assessed using trypan blue exclusion assay and in vivo antitumor activity was assessed by screening the ILS, serum liver marker enzymes and histopathology of the liver. Statistical Analysis Used: The data were expressed as the mean ± standard deviation of the means, and statistical analysis was carried out employing one-way and two-way analysis of variance using Web Agri Stat Package 2.0. Results: The dose-dependent percentage scavenging of ABTS, DPPH, FRAP, OH, superoxide radical, and nonradical NO and H2O2 by TdFf indicated their antioxidative potential. Incubation of EAC/DLA tumor cells with TdFf showed a concentration-dependent cytotoxic effect, and the extract killed 50% of EAC/DLA tumor cells at a concentration of 80 μg of TdFf. Coadministration of TdFf with EAC/DLA-induced mice showed a significant increase in the liver enzymic and nonenzymic antioxidants and significant decrease in the serum liver marker enzymes to prove the in vivo antioxidative and antitumor activity of TdFf. It was also confirmed by the histopathology of the liver. Conclusions: It may be concluded that the flavonoid fractions of Td possess considerable antioxidative and antitumorigenic activity against the tested DLA/EAC in both in vitro and in vivo system"

Enzymatic and Non Enzymatic Antioxidant Activity of Tabernaemontana divaricate R.Br. against DEN and Fe-NTA Induced Renal Damage in Wistar Albino Rats.

Plant derived drugs have been a part of the evolution of human healthcare for thousands of years. The present study was carried out to evaluate the antioxidant potential of ethanolic extract of Tabernaemontana divaricata on DEN initiated and Fe-NTA promoted renal damage in rats. Fe-NTA was induced after 10 days of DEN (200mg/kg body weight) initiation at a dose level of 9mg Fe-NTA/kg body weight twice a week for one month. The biochemical parameters were analyzed in serum and the antioxidant assays were carried out in kidney. Lipid peroxidation level was increased due to the administration of Fe-NTA, which caused the reduction of enzymatic antioxidant such as SOD, GPx, Catalase, G6PD, and also the non-enzymatic antioxidants vitamin C and GSH. The levels of urea, uric acid, creatinine, blood urea nitrogen were increased and protein level decreased on Fe- NTA intoxication. The secondary metabolites present in the plant increased the synthesis of antioxidant enzymes and its free radical scavenging properties helped to scavenge all free radicals thereby decreasing lipid peroxidation. Thus, the present study indicates that the plant may clinically valuable agent in the prevention of renal failure caused by DEN and Fe-NTA intoxication.

Effect of various extracts of Tabernaemontana divaricata on haloperidol induced catalepsy in rats.

Parkinson’s disease (PD) is one of the neurodegenerative diseases with selective loss of dopamine neurons of the substantia nigra pars compacta. In the present study, anti-cataleptic activity of Tabernaemontana divaricata leaves extracts viz. aqueous and ethanolic at different doses (50, 100 and 150 mg/kg i.p.) were studied using haloperidol (1 mg/kg, i.p.) induced catalepsy in rats which is a useful animal model for screening drugs for Parkinson’s disease. Both the extracts were found to reduce catalepsy significantly (P<0.001) as compared to the haloperidol treated rats showing greater effect at 150 mg/kg i.p. dose. Thus the present study reveals the anti-cataleptic activity of Tabernaemontana divaricata evaluating the traditional folklore medicinal use of the plant.

Effect of various extracts of Tabernaemontana divaricata on haloperidol induced catalepsy in rats.

Parkinson’s disease (PD) is one of the neurodegenerative diseases with selective loss of dopamine neurons of the substantia nigra pars compacta. In the present study, anti-cataleptic activity of Tabernaemontana divaricata leaves extracts viz. aqueous and ethanolic at different doses (50, 100 and 150 mg/kg i.p.) were studied using haloperidol (1 mg/kg, i.p.) induced catalepsy in rats which is a useful animal model for screening drugs for Parkinson’s disease. Both the extracts were found to reduce catalepsy significantly (P<0.001) as compared to the haloperidol treated rats showing greater effect at 150 mg/kg i.p. dose. Thus the present study reveals the anti-cataleptic activity of Tabernaemontana divaricata evaluating the traditional folklore medicinal use of the plant.

In vivo anti-inflammatory activity of Tabernaemontana divaricata leaf extract on male albino mice / 中国天然药物

AIM@#To study the in vivo anti-inflammatory activity of Tabernaemontana divaricata leaf extract on male albino mice.@*METHODS@#Aqueous decoction and methanol leaf extracts were tested for their ability to reduce croton oil-induced edema in the mouse ear after topical application. The methanol leaf extract dose-dependently inhibited the croton oil-induced ear edema in mice (ID50 <500 μg·cm(-2)). A bioassay-guided liquid-liquid fractionation of this methanol extract gave four active fractions: water insoluble (F1), hexane (F2), ethyl acetate (F3) and water (F4).@*RESULTS@#The hexane fraction showed a very high activity (42.1% inhibition at 0.7 μg·cm(-2)) as compared to the control. The other fractions were less active (F1: 56.1% at 506.2 μg·cm(-2); F3: 57.3% at 289.3 μg·cm(-2); and F4: 31.9% for 203.8 μg·cm(-2)) while indomethacin gave 48.8% of inhibition at 90 μg·cm(-2). The activity of F1 and F3 may be at least in part explained by the presence of anti-inflammatory flavonoids, while the activity was not correlated to the tannin contents. No compounds were detected in the most active F2 fraction.@*CONCLUSIONS@#The results give a rational support to the traditional use of T. divaricata in tropical India as anti-inflammatory agent.

Antioxidant and cytotoxic potential of methanol extract of Tabernaemontana divaricata leaves.

The methanolic extract obtained from the leaves of Tabernaemontana divericata (Family: Apocynaceae) was evaluated for in vitro antioxidant potential by determination of total antioxidant capacity, assay of nitric oxide scavenging activity and reducing power test. The extract was also screened for its cytotoxic effect using brine shrimp lethality bioassay. The results revealed potent antioxidant property in all antioxidant assays compared to the reference antioxidant, ascorbic acid in a dose dependent manner. Further, the methanolic extract of Tabernaemontana divericata showed significant cytotoxic effect (LC50: 3.12μg/ml) compared with positive control, Vincristine Sulphate (LC50: 0.331μg/ml).

Antioxidant and cytotoxic potential of methanol extract of Tabernaemontana divaricata leaves.

The methanolic extract obtained from the leaves of Tabernaemontana divericata (Family: Apocynaceae) was evaluated for in vitro antioxidant potential by determination of total antioxidant capacity, assay of nitric oxide scavenging activity and reducing power test. The extract was also screened for its cytotoxic effect using brine shrimp lethality bioassay. The results revealed potent antioxidant property in all antioxidant assays compared to the reference antioxidant, ascorbic acid in a dose dependent manner. Further, the methanolic extract of Tabernaemontana divericata showed significant cytotoxic effect (LC50: 3.12μg/ml) compared with positive control, Vincristine Sulphate (LC50: 0.331μg/ml).

Gastroprotective Effect of Tabernaemontana divaricata (Linn.) R.Br. Flower Methanolic Extract in Wistar Rats.

Tabernaemontana divaricata (L.) R.Br belonging to Apocynaceae family is traditionally used by people in many parts of the world to treat various disorders. The present study was undertaken to investigate anti-ulcer property of Tabernaemontana divaricata flower methanolic extract (TDFME 500 mg/kg, p.o) by pyloric ligation induced gastric ulceration model using Omeprazole (8mg/kg, p.o) as a standard drug in wistar rats. Five parameters i.e., volume of gastric juice, pH, free & total acidities and ulcer index were assessed. The test extract significantly (p< 0.01) decreased volume of gastric juice, free & total acidities and ulcer index. Like standard, it also raised pH of gastric acid. The observed percentage protection for standard and test were 89.84% and 79.53%, respectively. Thus, TDFME 500 mg/kg had a positive effect on all the parameters under study and the results were similar to that of standard. From the above results, it can be concluded that TDFME exhibits remarkable gastroprotective effect.

Reversible acetylcholinesterase inhibitory effect of Tabernaemontana divaricata extract on synaptic transmission in rat CA1 hippocampus.

Background & objectives: Acetylcholinesterase inhibitors (AChE-Is) are used for the treatment of Alzheimer’s disease (AD). These drugs including galanthamine have been shown to modulate synaptic activity in hippocampus and improve memory processes. Although Tabernaemontana divaricata extract (TDE) has been used as traditional medicine for various pharmacological effects, its effect in enhancing cholinergic activity provides additional benefit to its known effects. We investigated whether TDE can modulate the synaptic function in hippocampus and compared its effects to those of galanthamine. Methods: Hippocampal slices were prepared from male wWistar rats, functional effects of TDE were characterized by using pharmacological tools and extracellular recordings of field excitatory postsynaptic potentials (fEPSPs). Results: TDE significantly reduced fEPSPs. The fEPSPs reduction was prevented by atropine, but not pancuronium. These TDE effects were similar to those of galanthamine. Interpretation & conclusions: Our findings indicate that TDE can effectively modulate synaptic responses in the hippocampus similar to galanthamine, suggesting that this traditional medicine could be beneficial in ageing with ACh deprivation in the brain.

Study on chemical constituents of Tabernaemontana divaricata (II) / 第二军医大学学报

Objective: To extract and identify the chemical constituents in the roots and stems of Tabernaemontana divaricata. Methods: The solvent extraction and silica column chromatography were used to separate the chemical constituents, and their structures were identified by physicochemical properties and spectra analysis. Results: Six compounds were isolated and their structures were identified as his (2, 3-dihydroxypropyl) octacosanedioate (1), tetratriacontanol (2), palmitic acid (3), glycerol monopalmitatel (4), β-sitosterol (5), and β-daucosterol (6). Conclusion: Compound 1 is a new glyceroesters: compounds 2,3 and 4 are isolated from Tabernaemontana genus for the first time.