Antiproliferative, apoptotic induction, and antiinvasive effects of Leersia hexandra (L.) Sw., Panicum repens Linn., and Brachiaria mutica (Forsk.) Stapf extracts on human cancer cells

In vitro study of antiproliferation and cytotoxicity of the hexane and butanolic extracts of the three grass species, namely Leersia hexandra (L.) Sw. (“Yaa sai”), Panicum repens Linn. (“Yaa channakaat”), and Brachiaria mutica (Forsk.) Stapf (“Yaa khon”) demonstrated selective antiproliferative properties in both human lung cancer A549 and cervical cancer HeLa cell lines relative to normal human lung fibroblasts MRC-5, with significant differences in IC50 values (p<0.05). The butanolic extract of P. repens Linn. displayed the strongest growth inhibition in A549 and HeLa cells (IC50 2 and 1.1 mg/ml, respectively), whereas all other extracts exhibited only moderate to low antiproliferative effects (IC50 values, 90-980 mg/ml). Most grass extracts induced cell lethality at higher concentrations, suggesting their cytotoxic effects. The ELISA-based apoptosis assay showed that the hexane extract of these grasses triggered a significant increase in the level of apoptosis(p<0.05) in treated A549 cells. However, all the extracts induced ladder-like DNA fragmentation in both tumor cell lines ina dose- and time-dependent manner, suggesting that these extracts exhibit cytotoxicity through apoptotic induction. The studyof anti-invasive effects of the three grass species revealed that the hexane extract of L. hexandra (L.) Sw. (50-100 g/ml) and butanolic extract of P. repens Linn. (1 g/ml) effectively reduced the invasive capacity of MDA-MB-231 cells

Synergistic growth inhibitory effects of Phyllanthus emblica and Terminalia bellerica extracts with conventional cytotoxic agents: Doxorubicin and cisplatin against human hepatocellular carcinoma and lung cancer cells

AIM: To examine the growth inhibitory effects of Phyllanthus emblica (P. emblica) and Terminalia bellerica (T. bellerica) extracts on human hepatocellular carcinoma (HepG2), and lung carcinoma (A549) cells and their synergistic effect with doxorubicin or cisplatin. METHODS: HepG2 and A549 cells were treated with P. emblica and T. bellerica extracts either alone or in combination with doxorubicin or cisplatin and effects on cell growth were determined using the sulforhodamine B (SRB) assay. The isobologram and combination index (CI) method of Chou-Talalay were used to evaluate interactions between plant extracts and drugs. RESULTS: P. emblica and T. bellerica extracts demonstrated growth inhibitory activity, with a certain degree of selectivity against the two cancer cell lines tested. Synergistic effects (CI < 1) for P. emblica/doxorubicin or cisplatin at different dose levels were demonstrated in A549 and HepG2 cells. The T. bellerica/cisplatin or doxorubicin also showed synergistic effects in A549 and HepG2 cells. In some instances, the combinations resulted in antagonistic effects. The dose reduction level was different and specific to each combination and cell line. CONCLUSION: The growth inhibitory activity of doxorubicin or cisplatin, as a single agent, may be modified by combinations of P. emblica or T. bellerica extracts and be synergistically enhanced in some cases. Depending on the combination ratio, the doses for each drug for a given degree of effect in the combination may be reduced. The mechanisms involved in this interaction between chemotherapeutic drugs and plant extracts remain unclear and should be further evaluated

Apoptotic induction activity of Dactyloctenium aegyptium (L.) P.B. and Eleusine indica (L.) Gaerth. extracts on human lung and cervical cancer cell lines

Dactyloctenium aegyptium (L.) P.B. (Yaa paak khwaai) and Eleusine indica (L.) Gaerth. (Yaa teen-ka) have long been used in traditional Thai medicine because of their diuretic, anti-inflamatory, and antipyretic effects. The present study examined the antiproliferative and cytotoxic effects of the hexane and butanolic extracts of these two grass species. All the grass extracts exhibited selective growth inhibition effect on human lung cancer (A549) and cervical cancer (HeLa) cells relative to normal human lung MRC-5 fibroblasts with IC50 values in a range of 202 to 845 mg/ml. Apparently, HeLa cellswere more sensitive to the extracts than A549 cells. Moreover, all the extracts induced lethality in both cancer cell lines atconcentrations close to 1,000 mg/ml, indicating their selective cytotoxicity effects. ELISA assay showed that only the hexaneextract of D. aegyptium (L.) P.B. and E. indica (L.) Gaerth. significantly increased the apoptotic level in extract-treatedA549 cells. However, DNA ladder assay detected classic DNA ladder patterns, a characteristic feature of apoptosis, in both cancer cell lines treated with all the extracts in a dose- and time-dependent manner. Taken together, these results indicatethat the cytotoxic activity of the grass extracts against lung and cervical cancer cells is mediated through the induction ofapoptosis

Antioxidant activities of the standardized water extract from fruit of Phyllanthus emblica Linn

Abstract Phyllanthus emblica Linn. is widely used in Thai traditional medicine for treatment of various diseases. The fruit of P. emblica is known as a rich source of vitamin C, and also contains a mixture of phenolic compounds. In this study, the standardized water extract of P. emblica fruit was prepared according to Thai Herbal Pharmacopoeia. Total polyphenol contents of the extract were equivalent to 34.22±1.74 g gallic acid/100g extract. Antioxidant activities of the P. emblica extract were evaluated by several methods, including DPPH and ABTS •+ radical scavenging assays and FRAP assays. The results showed that the extract has an ability of scavenging radicals generated by both DPPH and ABTS •+ . Similar to Trolox, the water extract of P. emblica fruit also had a ferric reducing property. Additionally, the extract effectively inhibited H 2 O 2 -induced free radical production in human myeloleukemic U937 cells as measured by 2,7-DCF-DA. The results imply that the fruits of P. emblica are potential sources of natural antioxidants, which have free radical scavenging activity and might be useful for hepato-, cyto-, and radio-protection, as well as reducing oxidative stress in many pathological conditions