Anti-apoptotic effect of Buchholzia coriacea Engl. stem back extracts on AsPC-1 and mechanisms of action.

ETHNOPHARMACOLOGICAL RELEVANCE: Buchholzia coriacea Engl. is popularly called wonderful cola due to its wide ethnomedicinal use for the treatment of various ailments. We investigated the possible cytotoxic effect of its various fractions on human pancreatic cancer cell (AsPC-1) and also determined its mechanisms of action. MATERIALS AND METHODS: The AsPC-1 cells were cultivated and separately treated with 5-fluorouracil (5-FU) or Buchholzia coriacea Engl. bark (BC) (ethanol, aqueous, chloroform or ethyl acetate extract) for 72 h. Cell viability, caspase 3 and mitochondrial membrane potential (ΔΨm) were determined in vitro after the treatment. Nitric oxide (NO) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals' scavenging property, ferric reducing power and lipid peroxidation assays were also done to examine the antioxidant effect of BC in vitro. RESULTS: Various extracts of BC, especially at 2500 µg/ml and 5000 µg/ml, increased the AsPC-1 viability while 5-FU decreased it. The activity of caspase 3 was increased by 5-FU but reduced by all concentrations of various extracts of BC. Incubation of AsPC-1 with 5-FU showed the majority of cells having the monomeric form of JC-1 dye (bright green fluorescence), which indicated de-energized mitochondria. However, fluorescence photomicrograph of cells incubated with different concentrations (20, 40 and 100 µg/ml) of BC extracts (aqueous, ethanol, chloroform and ethyl acetate) showed strong JC-1 aggregation (yellow), which indicated mitochondria with intact membrane potentials. BC extracts also scavenged NO and DPPH radicals, inhibited lipid peroxidation and increased ferric reduction, though not as much as ascorbic acid. CONCLUSION: This study suggests that BC elicits anti-apoptotic activity in AsPC-1 by increasing cell viability, decreasing caspase 3 activity, stabilizing the ∆Ψm, and scavenging free radicals. Even though BC is used ethnomedicinally as anti-cancer agent, our findings in the present study suggest that it has pro-cancer potential in-vitro, especially on pancreatic cells. Its anti-apoptotic activity in AsPC-1 could be of clinical significance, especially to counteract the effect of apoptotic agents on pancreatic cells.

Annona muricata Linn and Khaya grandifoliola C.DC. Reduce Oxidative Stress In Vitro and Ameliorate Plasmodium berghei-Induced Parasitemia and Cytokines in BALB/c Mice.

BACKGROUND: Annona muricata and Khaya grandifoliola are ethnomedicinally used for the treatment of malaria and have been experimentally shown to have an anti-plasmodial effect, but the mechanisms involved are not fully understood. This study investigated the effect of the ethanol extracts of their leaves on parasitemia, radical scavenging and cytokines in Plasmodium berghei ANKA-infected BALB/c mice. METHODS: BALB/c mice were infected with P. berghei and treated with chloroquine, A. muricata or K. grandifoliola extract for 4 days. The percentage of parasitemia and the level of cytokine expression were determined after treatment. Trace element, phytochemical and nitric oxide (NO) scavenging activity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging properties assays were done to study the antioxidant effects of AN and KG in vitro. RESULTS: P. berghei consistently increased parasitemia in BALB/c mice. The tested doses (100-, 200-, and 400 mg/kg) of A. muricata and K. grandifoliola attenuated the P. berghei-induced elevation of parasitemia and cytokines (TNF-α, IL-5, and IL-6) in vivo during the experimental period, though not as much as chloroquine. Moreover, both extracts scavenged the DPPH and NO radicals, though A. muricata had more anti-oxidant effect than K. grandifoliola in-vitro. CONCLUSION: The ethanol extracts of A. muricata and K. grandifoliola reduce parasitemia in P. berghei-treated mice BALB/c by scavenging free radicals and reducing cytokines, though the extracts were not as effective as chloroquine.