Cytotoxicity of some Cameroonian spices and selected medicinal plant extracts

https://doi.org/10.1016/j.jep.2011.01.035Get rights and content

Abstract

Ethnopharmacological relevance

Several medicinal plants and spices are used traditionally to treat cancers in Cameroon.

Aim

Methanol extracts from thirty-four spices and plants, with related ethnobotanical use were investigated for their in vitro cytotoxicity on the human pancreatic cancer cell line MiaPaCa-2, leukemia CCRF-CEM cells and their multidrug resistant (MDR) subline CEM/ADR5000, and the normal human umbilical vein endothelial cells (HUVECs). In addition the anti-angiogenic properties of the most active extracts were investigated.

Material and methods

The MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay was used for cytotoxic studies and the CAM-assay (chicken-chorioallantoic-membrane-assay) for anti-angiogenesis test.

Results

The results of the cytotoxicity tests indicated that, when tested at 20 μg/ml, extracts from Xylopia aethiopica, Echinops giganteus, Imperata cylindrica, Dorstenia psilirus and Piper capense were able to inhibit more that 50% the proliferation of the three tested cancer cells (MiaPaCa-2, CEM/ADR5000 CCRF-CEM). The lowest IC50 values of 6.86 μg/ml on MiaPaCa-2 and 3.91 μg/ml on CCRF-CEM cells were obtained with X. aethiopica, while the corresponding value of 6.56 μg/ml was obtained with P. capense on CEM/ADR5000 cells. Against leukemia cells, no cross-resistance was observed with I. cylindrica, P. capense and Zinziber officinalis. Extracts from D. psilirus and E. giganteus were able to inhibit angiogenesis by more than 50% in quail embryo.

Conclusion

The overall results of the present study provide supportive data on the use of some Cameroonian plants for cancer treatment.

Graphical abstract

Effects of selected plant extracts (at 20 μg/ml) on the growth of blood capillaries on the chorioallantoic membrane of quail eggs. (A) DMSO (control): normal growth of blood capillaries on the CAM – no antiangiogenic effect; (B) Xylopia aethiopica; (C) Dorstenia psilirus; (D) Echinops giganteus; (E) Zinziber officinale. Extracts from D. psilirus and E. giganteus significantly inhibited angiogenesis in quail embryo.

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Introduction

Pancreatic cancer is one of the most aggressive solid malignancies with high rate of resistance to most of the available treatment modalities, such as chemotherapy and radiotherapy (Wente et al., 2008). Only 20% of pancreatic cancers are amenable to surgical resection at presentation and despite the medical advances made over the last 20 years, pancreatic cancer appear to have benefited the least in terms of survival (Garcea et al., 2005). In the case of leukemia, MDR phenotypes have become a major concern to effective treatment. It is therefore important to develop new therapeutic strategies to treat malignancies. It was reported that excessive angiogenesis is an important factor of the pathogenesis of many industrialized western countries (Krenn and Paper, 2009). Therefore, compounds with anti-angiogenic properties are of importance in the treatment and prevention of malignancies as well as other chronic diseases (Paper, 1998, Carmeliet, 2003). Screenings of medicinal plants used as anticancer drugs have provided modern medicine with effective cytotoxic pharmaceuticals. More than 60% of the approved anticancer drugs in United State of America (from 1983 to1994) were from natural origin (Stévigny et al., 2005, Newman and Cragg, 2007). In the Cameroonian pharmacopoeia, there are still serious lacks of information on the use of large numbers of plants and spices traditionally employed in the treatment of several ailments, including cancers. It belongs to the scientific community to fill this gap. However, it has been recommended that ethnopharmacological usages such as immune and skin disorders, inflammatory, infectious, parasitic and viral diseases should be taken into account when selecting plants used to treat cancer, since these reflect disease states bearing relevance to cancer or cance-liker symptoms (Cordell et al., 1991, Popoca et al., 1998). Therefore, the present work was designed to investigate the cytotoxicity of some plants and spices used locally in Cameroon to treat cancers, but not inventoried in the national pharmacopoeia. The study was extended to the search of anti-angiogenic properties of some of the most active extracts.

Section snippets

Plant material and extraction

All medicinal plants used in the present work were collected in Dschang, western region of Cameroon, between January and February 2009. The spices were obtained from Dschang local market at the same period. The plants were identified at the National Herbarium (Yaounde, Cameroon) where voucher specimens were deposited under the references numbers (Table 1). The air-dried and powdered plant material was soaked in methanol for 48 h, at room temperature. The methanol extract was concentrated under

Results and discussion

In the US NCI plant screening program, a crude extract is generally considered to have in vitro cytotoxic activity, if the IC50 value following incubation between 48 and 72 h, is less than 20 μg/ml (Boik, 2001). In the present work, thirty-four selected plant extracts were tested (at 20 μg/ml) for their cytotoxic effects, and the results are summarized in Fig. 1, Fig. 2, Fig. 3 and Table 2. The results of Fig. 1, Fig. 2, Fig. 3 indicate that extracts from six of the 34 (17.6%) plants were able to

Acknowledgements

Authors are thankful to the National Herbarium of Cameroon (Yaounde). V.K. is also very grateful to the German Academic Exchange Service (DAAD) for the travel grant at the Johannes-Gutenberg University, Mainz, Germany.

References (119)

  • M.M. Iwu et al.

    Evaluation of the anthihepatotoxic activity of the biflavonoids of Garciaria kola seeds

    Journal of Ethnopharmacology

    (1987)
  • S.C. Joshi et al.

    Antioxidant and antibacterial activities of the leaf essential oils of Himalayan Lauraceae species

    Food and Chemical Toxicology

    (2010)
  • U. Justesen et al.

    Quantitative analysis of flavonols, flavones, and flavanones in fruits, vegetables and beverages by HPLC with photodiode array and mass spectrometric detection

    Journal of Chromatography A

    (1998)
  • A.M. Kaou et al.

    New amide alkaloid from the aerial part of Piper capense L.f. (Piperaceae)

    Fitoterapia

    (2010)
  • H. Kojima et al.

    Sterol glucosides from Prunella vulgaris

    Phytochemistry

    (1990)
  • L. Krenn et al.

    Inhibition of angiogenesis and inflammation by an extract of red clover (Trifolium pratense L.)

    Phytomedecine

    (2009)
  • V. Kuete et al.

    Antimicrobial activity of the methanolic extracts and compounds from Treculia obovoidea (Moraceae)

    Journal of Ethnopharmacology

    (2007)
  • V. Kuete et al.

    Antimicrobial activity of the methanolic extract and compounds from Teclea afzelii (Rutaceae)

    South African Journal of Botany

    (2008)
  • V. Kuete et al.

    Diospyrone, crassiflorone, and plumbagin. three antimycobacterial and anti-gonorrheal naphthoquinones from two Diospyros species

    International Journal Antimicrobial Agents

    (2009)
  • M.L. Kuo et al.

    Genotoxicities of nitropyrenes and their modulation by apigenin, tannic acid, ellagic acid and indole-3-carbinol in the Salmonella and CHO systems

    Mutation Research

    (1992)
  • C.M. Lok et al.

    Kombic acid, a hydroquinone polyisoprenoic carboxylic acid from Pycnanthus kombo seed fat

    Phytochemistry

    (1983)
  • R.M. Ngoumfo et al.

    In vitro cytotoxic activity of isolated acridones alkaloids from Zanthoxylum leprieurii Guill. et Perr

    Bioorganic and Medicinal Chemistry

    (2010)
  • K. Nishimoto et al.

    The structure of arundoin, cylindrin and fernenol triterpenoids of fernane and arborane groups of Imperata cylindrica var. Koenigii

    Tetrahedron

    (1968)
  • J.I. Nwaiwu et al.

    Anticonvulsant activity of the volatile oil from the fruit of Tetrapleura tetraptera

    Journal of Ethnopharmacology

    (1986)
  • A.M. Nyemba et al.

    Cycloartane derivatives from Garcinia lucida

    Phytochemistry

    (1990)
  • O. Omobuwajo et al.

    Cytotoxic cycloartanes from Aglaia argentea

    Phytochemistry

    (1992)
  • J. Popoca et al.

    Cytotoxic activity of selected plants used as antitumorals in Mexican traditional medicine

    Journal of Ethnopharmacology

    (1998)
  • P. Tane et al.

    Cyclodione, an unsymmetrical dimeric diterpene from Cylicodiscus gabunensis

    Tetrahedron

    (1995)
  • B.M. Abegaz et al.

    Chemistry of the genus Dorstenia

    Current Organic Chemistry

    (2000)
  • M. Abrantes et al.

    Antiplasmodial activity of lignans and extracts from Pycnanthus angolensis

    Planta Medica

    (2008)
  • J.E. Adjanohoun et al.

    Traditional Medicine and Pharmacopoeia: Contribution to Ethnobotanical and Floristic Studies in Cameroon

    (1996)
  • C.O. Adewunmi et al.

    Evaluation of aridanin, a glycoside, and aridan, an aqueous extract of Tetrapleura tetraptera fruit, on Schistosoma mansoni and S. bovis

    Journal of Ethnopharmacology

    (1989)
  • E.O. Ajaiyeoba et al.

    In vitro anthelmintic properties of Buchholzia coriaceae and Gynandropsis gynandra extracts

    Pharmaceutical Biology

    (2001)
  • J.F. Akoachere et al.

    Antibacterial effect of Zingiber officinale and Garcinia kola on respiratory tract pathogens

    East African Medical Journal

    (2002)
  • T.A. Al-Howiriny et al.

    Preliminary evaluation of the anti-inflammatory and anti-hepatotoxic activities of ‘Parsley’ Petroselinum crispum in rats

    Journal of Natural Remedies

    (2003)
  • Anon.

    British Herbal Pharmacopoeia

    (1983)
  • S.K. Ashan et al.

    Studies on some herbal drugs used against kidney stones in Saudi Folk medicine

    Fitoterapia

    (1990)
  • H.K. Bakhru

    Herbs that Heal Natural Remedies for Good Health

    (1998)
  • D.F. Birt et al.

    Inhibition of ultraviolet light-induced skin carcinogenesis in SKH-1 mice by apigenin, a plant flavonoid

    Anticancer Research

    (1997)
  • J. Boik

    Natural Compounds in Cancer Therapy

    (2001)
  • A. Bouquet

    Feticheurs et medicines traditionnelles du Congo Brazzaville

    (1969)
  • P. Carmeliet

    Angiogenesis in health and disease

    Nature Medicine

    (2003)
  • P.F. D’Arcy et al.

    A new anti-inflammatory test, utilizing the chorioallantoic membrane of the chick embryo

    British Journal of Pharmacology and Chemotherapy

    (1967)
  • J.M. Dalziel

    The Useful Plants of West Tropical Africa

    (1936)
  • J.M. Dalziel

    The Useful Plants of West Tropical Africa

    (1948)
  • M.A. Diniz et al.

    Contribution to the knowledge of medicinal plants from Guinea-Bissau

    Portugaliae Acta Biologica

    (2007)
  • J.P. Dzoyem et al.

    In vitro antifungal activity of extract and plumbagin from the stem bark of Diospyros crassiflora Hiern (Ebenaceae)

    Phytotherapy Research

    (2007)
  • A.S. Ekop

    Determination of chemical composition of Gnetum africanum (AFANG) seeds

    Pakistan Journal of Nutrition

    (2007)
  • M.P. Ferry et al.

    Vegetative Propagation of Shea, Kola And Pentadesma. Cocoa Research Institute, Ghana Annual Report (1987/88)

    (1974)
  • D.M. Fort et al.

    Novel antihyperglycemic terpenoid–quinones from Pycnanthus angolensis

    Journal of Organic Chemistry

    (2000)
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