Absorption of andrographolides from Andrographis paniculata and its effect on CCl(4)-induced oxidative stress in rats.

A simple and validated high-performance liquid chromatography (HPLC) method with UV detection has been used to determine the content of andrographolide (AP) and 14-deoxy-11,12-didehydroandrographolide (DIAP) in rat plasma after oral dose of methanol extract (1 g/kg body weight) of Andrographis paniculata leaf. An increase in plasma concentration of AP and DIAP was observed from 30 min to 3 h after oral administration of the extract. The maximum plasma concentrations of AP and DIAP were 1.42+/-0.09 microg/ml and 1.31+/-0.04 microg/ml, respectively. Fourteen days oral treatment of rats with the methanol extract (1 g/kg body weight) followed by CCl(4) administration preserved catalase (CAT), and superoxide dismutase (SOD) activities in erythrocytes, whereas plasma lipid peroxidation, alanine transaminase (ALT) and aspartate transaminase (AST) activities were restored to values comparable with control values. Treatment of rats with CCl(4) did not showed significant alteration (p>0.05) in plasma total antioxidant status (TAS) as compare to values of control group.

Determination of betulinic acid from Orthosiphon stamineus leaf extract in rat plasma.

A simple high-performance liquid chromatography (HPLC) method to determine the content of betulinic acid (BA) in rat plasma collected at different times (0-8 h) after oral administration of Orthosiphon stamineus leaf extract was developed. The features of the assay include protein precipitation using acetonitrile and isocratic elution using reverse phase C-18 column with ultraviolet (UV) detection. The recovery of BA from plasma varied from 98.4 to 102.5%. The R.S.D of intra- and inter-day precision from rat plasma ranged from 4.2 to 9.8%. The maximum concentration of BA in the plasma was 1.2 +/- 0.3 microg/ml at 1 h after oral administration of the extract.

Analysis of urinary andrographolides and antioxidant status after oral administration of Andrographis paniculata leaf extract in rats.

A simple high-performance liquid chromatography (HPLC) method was developed to determine the content of andrographolide (AP) and 14-deoxy-11,12-dideoxyandrographolide (DIAP) in a pooled urine of rat obtained within 24h after an oral dose of Andrographis paniculata leaf extract at 1g/kg body weight. Cumulative urinary excretion of AP and DIAP in 24h after oral administration of the extract was 0.88% and 1.61% of oral dose administered, respectively. The extract showed significant reduction (p<0.05) of MDA levels and elevation of total antioxidant status in rat urine samples collected in 24 after oral administration.

Studies on diuretic and hypouricemic effects of Orthosiphon stamineus methanol extracts in rats.

AIM OF THE STUDY: Orthosiphon stamineus (Labiatae) is a traditional folk medicine widely used in Southeast Asia for the treatment of several kidney disorders, gout and as a diuretic. This study was conducted to examine the diuretic and hypouricemic effects of Orthosiphon stamineus leaf extracts. MATERIALS AND METHODS: The diuretic effect of different methanol extracts was examined by treating different groups of Sprague-Dawley rats with single (2g/kg) oral doses of methanol and methanol:water (1:1) extracts. Hydrochlorothiazide (10mg/kg) was used as positive control in acute study. Methanol and methanol water (1:1) extracts at 0.5 g/kg were administered for a period of 7 consecutive days. Cumulative urine volume and electrolytes (Na+ and K+) concentrations at different time intervals were measured. On the other hand, hypouricemic activity of methanol:water extract (1:1) was experimented using different oral single doses (0.25, 0.5, 1 and 2g/kg). Allopurinol was used as positive control. Uric acid concentration in serum was analyzed by using RP-HPLC at 280 nm. RESULTS: Sodium and potassium excretion increased significantly (p<0.05 and <0.01) in the first 8h of treatment with a single dose (2g/kg) of the extracts in a pattern comparable to that of the known diuretic hydrochlorothiazide. Meanwhile, repeated administration of 0.5 g/kg methanol:water (1:1) extract showed a significant increase in urine volume (from day 3 to day 7) (p<0.01) and electrolytes excretion (Na+ and K+) from day 2 to day 7 (p<0.05 and <0.01). On the other hand, 0.5, 1 and 2g/kg of methanol:water (1:1) extract and the standard allopurinol reduced the serum urate level in hyperuricemic rats at hour 6. CONCLUSION: These results provided an evidence of the high tendency of methanol:water (1:1) extract of Orthosiphon stamineus towards diuretic and hypouricemic effects in rats.

Effect of Eurycoma longifolia extract on the Glutathione level in Plasmodium falciparum infected erythrocytes in vitro.

In the present study we examined the effect of E. longifolia methanol extract (TA164) on the GSH levels of P. falciparum infected erythrocytes and uninfected erythrocytes. Our study on parasite growth shows the IC50 and IC75 values of TA164 to be 0.17 g/ml and 6 g/ml respectively while for BSO was 25.5 g/ml and 46.5 g/ml respectively. About 95% to 100% growth inhibition of P. falciparum infected erythrocyte was observed when treated with TA164 and BSO at 16 g/ml and 64 g/ml respectively. The study on GSH contents indicated that non-infected erythrocytes treated with 6 g/ml (IC75 values) of TA164 at 24 hours incubation showed less GSH content as compared to non-treated erythrocytes. A similar observation was seen on treated trophozoite infected erythrocyte (10% parasitemia) when treated with 6 g/ml at 3 hours incubation. Analysis of the GSH contents of parasite compartments treated with TA164 at the same concentration (6 g/ml) for 3 hours incubation indicated a reduction of GSH contents. At the same concentration, TA164 did not affect the GSH contents of enriched trophozoite infected erythrocytes (60-70% parasitemia). TA164 did affect the GSH content of non-infected erythrocyte at 24 hours (accept IC50 value) as well as the parasite compartments (trophozoite infected erythrocyte and parasite itself) but fails to affect the GSH content of enriched trophozoite infected erythrocyte.