Crateva adansonii DC, an African ethnomedicinal plant, exerts cytotoxicity in vitro and prevents experimental mammary tumorigenesis in vivo

Contribution of Sub-Saharan African medicinal plants to cancer research: Scientific basis 2013-2023

Cancer incidence and mortality rates are increasing worldwide. Cancer treatment remains a real challenge for African countries, especially in sub-Saharan Africa where funding and resources are very limited. High costs, side effects and drug resistance associated with cancer treatment have encouraged scientists to invest in research into new herbal cancer drugs. In order to identify potential anticancer plants for drug development, this review aims to collect and summarize anticancer activities (in vitro/in vivo) and molecular mechanisms of sub-Saharan African medicinal plant extracts against cancer cell lines. Scientific databases such as ScienceDirect, Google Scholar and PubMed were used to search for research articles published from January 2013 to May 2023 on anticancer medicinal plants in sub-Saharan Africa. The data were analyzed to highlight the cytotoxicity and molecular mechanisms of action of these listed plants. A total of 85 research papers covering 204 medicinal plant species were selected for this review. These plants come from 57 families, the most dominant being the plants of the family Amaryllidaceae (16), Fabaceae (14), Annonaceae (10), Asteraceae (10). Plant extracts exert their anticancer activity mainly by inducing apoptosis and stopping the cell cycle of cancer cells. Several plant extracts from sub-Saharan Africa therefore have strong potential for the search for original anticancer phytochemicals. Chemoproteomics, multi-omics, genetic editing technology (CRISPR/Cas9), combined therapies and artificial intelligence tools are cutting edge emerging technologies that facilitate the discovery and structural understanding of anticancer molecules of medicinal plants, reveal their direct targets, explore their therapeutic uses and molecular bases.

Current views on in vivo models for breast cancer research and related drug development

INTRODUCTION

Animal models play a crucial role in breast cancer research, in particular mice and rats, who develop mammary tumors that closely resemble their human counterparts. These models allow the study of mechanisms behind breast carcinogenesis, as well as the efficacy and safety of new, and potentially more effective and advantageous therapeutic approaches. Understanding the advantages and disadvantages of each model is crucial to select the most appropriate one for the research purpose.

AREA COVERED

This review provides a concise overview of the animal models available for breast cancer research, discussing the advantages and disadvantages of each one for searching new and more effective approaches to treatments for this type of cancer.

EXPERT OPINION

Rodent models provide valuable information on the genetic alterations of the disease, the tumor microenvironment, and allow the evaluation of the efficacy of chemotherapeutic agents. However, in vivo models have limitations, and one of them is the fact that they do not fully mimic human diseases. Choosing the most suitable model for the study purpose is crucial for the development of new therapeutic agents that provide better care for breast cancer patients.

Anticancer Activity of Rhizophora mucronata Leaves Extract on Sprague-Dawley Rats: In Vivo Model

Medicinal plants are now used to treat cancer due to the presence of bioactive compounds. Apart from the plants, mangroves also possess rich bioactive compounds with high medicinal activity. Based on the ethnobotanical attributes of Rhizophora mucronata, we are keen to work with its anticancer activity. The aim of the study is to assess the anticancer activity of methanolic extract of Rhizophora mucronata leaves against breast cancer. Its safety profile for anticancer investigations was therefore confirmed through an acute toxicity assessment. In accordance with OECD guiding principles, the study was approved to evaluate the toxicity, including acute and subacute effects and anticancer activities of methanolic extract of Rhizophora mucronata leaves on Sprague-Dawley rats. In acute toxicity trials, the dose of 1000 mg/kg body weight was determined to be safe and nontoxic even at high dose levels and did not result in any indicators of toxicity or death in the tested groups compared to controls for 14 days. In contrast, rats in a subacute toxicity study were given consistent doses of 100 mg/kg, 200 mg/kg, and 300 mg/kg for a total of 28 days along with a control group. Haematological, biochemical, and histological tests conducted in advance revealed that methanolic extract of Rhizophora mucronata leaves (MERML) at repeated doses of 200 mg/kg and 300 mg/kg was normal and had no significant effects on the treated groups. Rhizophora mucronata extract (250 mg/kg) was successfully used in in vivo trials to stop the growth of breast cancer cells in groups that had been given DMBA. Based on these findings, it has been concluded that methanolic extract of Rhizophora mucronata leaves (MERML) was safe at both higher and lower dosages and could be assessed for pharmacological study.

In Vitro and In Vivo Antiproliferative Actions of Solanum gilo Raddi (Solanaceae) Fruit Extract on Breast Tissues

Background

Menopause is a normal event characterized by a drop in estrogen's production, leading to numerous symptoms. To face these later, women rely on hormone replacement therapy (HRT), which alleviates numerous menopausal symptoms. Unfortunately, long-term exposure to estrogens is associated with an increase in endometrial and breast cancers. This study dealt with the evaluation of in vitro and in vivo antiproliferative effects of Solanum gilo Raddi, a plant used in folk medicine to treat tumors in Cameroon.

Materials and Methods

The in vitro antiproliferative effect of S. gilo fruit extract was investigated through the well-characterized MTT assay in one normal and three cancerous breast cells. For the in vivo study, one normal group (NOR) of rats received distilled water (vehicle), and five other groups (n = 6) were treated either with tamoxifen (3.3 mg/kg BW) as standard or with the vehicle (negative control) or S. gilo fruit hydroethanolic extract (125, 250, and 500 mg/kg BW). The treatments were administered concomitantly with the E2V to induce breast hyperplasia for 16 weeks, and the endpoints were the histopathology of the mammary glands and some biochemical parameters.

Results

The S. gilo extract significantly inhibited human (MCF-7 and MDA-MB-231) and rodent (4T1) breast carcinoma cell growth. Rats exposed only to E2V presented atypical mammary hyperplasia compared to the normal parenchyma observed in normal rats. While rats treated with S. gilo extract at the dose of 125 mg/kg BW showed a microarchitecture of mammary glands with moderate hyperplasia, the higher doses (250 and 500 mg/kg) inhibited mammary gland hyperplasia compared to the E2V group.

Conclusion

S. gilo fruit extract has antiproliferative constituents that could help to fight against estrogen-dependent breast cancer, thanks to their ability to scavenge free radicals, as exhibited in this study.

Therapeutic and Nutraceutical Effects of Polyphenolics from Natural Sources

The prevalence of cardiovascular disease, oxidative stress-related complications, and chronic age-related illnesses is gradually increasing worldwide. Several causes include the ineffectiveness of medicinal treatment therapies, their toxicity, their inability to provide radical solutions in some diseases, and the necessity of multiple drug therapy in certain chronic diseases. It is therefore necessary for alternative treatment methods to be sought. In this review, polyphenols were identified and classified according to their chemical structure, and the sources of these polyphenol molecules are indicated. The cardioprotective, ROS scavenging, anti-aging, anticancer properties of polyphenolic compounds have been demonstrated by the results of many studies, and these natural antioxidant molecules are potential alternative therapeutic agents.

Combination of selected Thai traditional pain relief medicinal plants with anti-inflammatory abilities in a protein denaturation assay

Crateva adansonii DC, Maerua siamensis (Kurz) Pax, and Mallotus repandus (Willd.) Müll. Arg. have long been used as ingredients in compound herbal medicines to relieve pain in Thailand. In this study, an albumin denaturation inhibition experiment was used to assess the anti-inflammatory properties of the ethanolic extracts of these plants and their mixture. Lupeol, the active molecule responsible for the anti-inflammatory activity, was chosen as a chemical marker for the extracts. All plant extracts demonstrated anti-inflammatory potential. Their IC50 values ranged from 1.19 to 7.31 mg/mL. This blend showed the strongest anti-inflammatory effect, with a 0.5-fold increase in activity when compared to diclofenac. Lupeol, an anti-inflammatory agent, is one of the chemical constituents of the selected medicinal plants. Its content ranged from 0.04 to 8.60% w/w, as determined by HPLC in this study. It means that the plants, alone and in combination, are a good source of herbs for further pharmacological study and product development.

Evaluating the therapeutic potential of white button mushroom (Agaricus bisporus) against DMBA-induced breast cancer in Sprague Dawley rats

The current research work was designed to investigate the protective effects of white button mushroom (Agaricus bisporus) against 7,12-dimethylbenz[a]anthracene (DMBA)-induced breast cancer. Breast cancer was induced in rats by the administration of a single dose of 50 mg/kg DMBA via gavage. The rats were divided into four groups: G1 (negative control group), G2 (positive control group), G3 (rats receiving mushroom extract), and G4 (rats administered with doxorubicin). The mushroom extract significantly (p < .001) improved the activity of antioxidant enzymes in carcinogenic rats. Moreover, the mushroom extract also prevented the increase in the concentration of tumor biomarkers that are CEA, CA 15.3, and CRP in experimental rats. Liver function enzymes were also raised in G2 and G4 compared with G3. Besides, the RBCs and Hb were also reduced significantly in G4 while in G3. The mushroom extract effectively controlled the level of RBCs and Hb. An improvement in lipid profile was also measured in mushroom extract receiving rats. Conclusively, the mushroom extract alleviated DMBA-induced breast cancer potentially via improving antioxidants, reducing lipid peroxidation, and decreasing tumor biomarkers. PRACTICAL APPLICATIONS: The present research study examined the antitumor potential of white button mushroom. The mushroom effectively prevented the increase in tumor biomarkers, reduction in antioxidant enzymes, and increase in lipid peroxidation in rats with DMBA-induced breast cancer. The mushroom can be used as a potential source to prevent breast cancer and further research can be conducted to explore its anticancer mechanisms.

Review On Documented Medicinal Plants Used For The Treatment Of Cancer

Background:

Cancer is a frightful disease and it is the second leading cause of death worldwide. Naturally derived compounds are gaining interest of research workers as they have less toxic side effects as compared to currently used treatments such as chemotherapy. Plants are the pool of chemical compounds which provides a promising future for research on cancer.

Objective:

This review paper provides updated information gathered on medicinal plants and isolated phytoconstituents used as anticancer agents and summarises the plant extracts and their isolated chemical constituents exhibiting anticancer potential on clinical trials.

Methods:

An extensive bibliographic investigation was carried out by analysing worldwide established scientific databases like SCOPUS, PUBMED, SCIELO, ScienceDirect, Springerlink, Web of Science, Wiley, SciFinder and Google Scholar etc. In next few decades, herbal medicine may become a new epoch of medical system.

Results:

Many researches are going on medicinal plants for the treatment of cancer but it is a time to increase further experimental studies on plant extracts and their chemical constituents to find out their mechanism of action at molecular level.

Conclusion:

The article may help many researchers to start off further experimentation that might lead to the drugs for the cancer treatment.

Anti-breast cancer potential of Anonidium mannii (Oliv.) Engl. & Diels barks ethanolic extract: UPLC-ESI-QTOF-MS detection of anticancer alkaloids

ETHNOPHARMACOLOGICAL RELEVANCE

Breast cancer is a serious threat in low-income as well as developed countries. To face this, many herbal preparations are prescribed by traditional healers in Cameroon, among which is Anonidium mannii commonly called "wild soursop".

AIM

This study was undertaken to assess the anti-tumor effect of A. mannii ethanolic extract on cancer cell growth and against DMBA-induced mammary tumors in rats.

MATERIALS AND METHODS

The well characterized MTT bioassay was used to assess the cytotoxic potential of A. mannii ethanolic extract in liver (HepG2), prostate (DU145 & PC3) and breast (MCF-7) cancer cell lines. Considering the fact that breast cells were the most sensitive to the extract, a 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast tumor rat model was used to assess the possible anticancer effect of A. mannii extract. Indeed, rats were treated with either tamoxifen (3.3 mg/kg BW) or A. mannii extract (16.5, 50 and 150 mg/kg BW) or vehicle (2% ethanol) for 20 weeks. Tumor incidence, tumor mass and volume, oxidative stress status in tumor as well as tumor histoarchitecture were evaluated.

RESULTS

A 24 h incubation of tested cells with the A. mannii extract significantly slowed cell growth in a concentration-dependent manner with an interesting effect in breast cells (IC50 ~61.5 μg/mL). As compared to the DMBA rats, those treated with A. mannii extract (50 and 150 mg/kg) showed reduced breast tumor incidence (28%), tumor burden (95.34% at 50 mg/kg and 99.14% at 150 mg/kg) and tumor volume (~92%). A. mannii extract counteracted the high proliferation of terminal mammary ducts induced by DMBA, mainly at 50 mg/kg. Furthermore, the extract decreased MDA and nitrite levels but increased SOD activity in the mammary gland. High Performance Liquid Chromatography coupled with Mass Spectrometry (HPLC-MS) analysis detected potential anticancer and antioxidant alkaloids in A. manni extract, which are close to those found in Annona muricata.

CONCLUSION

These results provide evidence on the in vitro and in vivo anticancer effects of A. mannii, and therefore support its use in traditional medicine system to fight against cancer.

Daucosterol from Crateva adansonii DC (Capparaceae) reduces 7,12-dimethylbenz(a)anthracene-induced mammary tumors in Wistar rats

This study aimed to evaluate the in vivo anticancer effects of daucosterol which was earlier reported to possess in vitro anticancer effects. Breast tumor was induced in 30 rats using the environmental carcinogen 7,12-dimethylbenz(a)anthracene (DMBA) while 6 control rats received olive oil (NOR). Animals with palpable tumors were randomized into five groups (n = 6) each as follows: negative control group treated with the vehicle (DMBA); positive control group treated with 5 mg/kg BW doxorubicin (DOXO + DMBA); three groups treated with daucosterol at doses of 2.5, 5, and 10 mg/kg BW (DAU + DMBA). Treatment lasted 28 days afterward, tumor (mass, volume, cancer antigen [CA] 15-3 level and histoarchitecture), hematological and toxicological parameters were examined. The tumor volume gradually increased in the DMBA group during the 28 days, with a tumor volume gain of ∼390 cm³ . Daucosterol at all doses reduced tumor volume (∼133.7 cm³ at 10 mg/kg) as well as protein, malondialdehyde (MDA), and CA 15-3 levels compared to DMBA rats. Tumor sections in daucosterol-treated rats showed a lower proliferation of mammary ducts with mild (5 and 10 mg/kg) to moderate (2.5 mg/kg) inflammatory responses. Moreover, it exhibited an antioxidant effect, evidenced by a significant and dose-dependent decreased in MDA levels, as well as an increase in catalase activity compared to the DMBA group. Daucosterol showed for the first time in vivo antitumor effects that corroborate its previous in vitro effects.

Abyssinone V-4' Methyl Ether, a Flavanone Isolated from Erythrina droogmansiana, Exhibits Cytotoxic Effects on Human Breast Cancer Cells by Induction of Apoptosis and Suppression of Invasion

Abyssinone V-4′ methyl ether (AVME) isolated from Erythrina droogmansiana was recently reported to exhibit anti-mammary tumor effect in mice. The present work was therefore aimed at elucidating its cellular and molecular mechanisms. To achieve our goal, the cytotoxicity of AVME against tumoral and non-tumoral cell lines was evaluated by resazurin reduction test; flow cytometry allowed us to evaluate the cell cycle and mechanisms of cell death; the mitochondrial transmembrane potential, reactive oxygen species (ROS) levels, and caspase activities as well as apoptosis-regulatory proteins (Bcl-2 and Bcl-XL) were measured in MDA-MB-231 cells. Further, the antimetastatic potential of AVME was evaluated by invasion assay. AVME exhibited cytotoxic effects in all tested tumor cell lines and induced a significant increase in the percentage of MDA-MB-231 cells at G2/M and S phases of the cell cycle in a concentration-dependent manner. AVME also induced apoptosis in MDA-MB-231 cells, which was accompanied by the activation of caspase-3 and caspase-9 and downregulation of Bcl-2 and Bcl-XL proteins. Moreover, AVME suppressed cancer cell invasion by the inhibition of the metalloproteinase-9 activity. Findings from this study suggest that AVME has anti-breast cancer activities expressed through mitochondrial proapoptotic pathway including impairment of aggressive behaviors of breast cancer cells.

Bioguided identification of daucosterol, a compound that contributes to the cytotoxicity effects of Crateva adansonii DC (capparaceae) to prostate cancer cells

ETHNOPHARMACOLOGICAL RELEVANCE

Crateva adansonii DC (Capparaceae) is a shrub used to treat tumors in Cameroon. In our previous reports, a Crateva adansonii dichloromethane-methanol (DCM/MeOH) extract was shown to prevent chemically induced tumors in Wistar rats.

AIM OF STUDY

To determine the bioactive principle of Crateva adansonii extract and to elucidate its underlying mechanism.

MATERIALS AND METHODS

An activity-guided fractionation was realized using MTT assay. To investigate if the bioactive compound daucosterol (CA2) accounted for the previously observed anticancer effects of the C. adansonii extract, it was tested on cell growth, cell proliferation, cell cycle, cell death mechanism and cell migration. In addition, cell cycle- and apoptosis-regulating proteins were assessed by Western blotting.

RESULTS

Daucosterol (CA2), a steroid saponin, was identified as major anticancer principle of the C. adansonii extract. Daucosterol significantly inhibited LNCaP, DU145 and PC3 prostate carcinoma cell growth and proliferation at the optimal concentration of 1 μg/mL. It also significantly increased the number of late apoptotic (DU145) and apoptotic (PC3) cells. The number of cells in S phase increased in DU145, while the number of G0/G1 cells decreased. Cell cycle proteins (cdk1, pcdk1, cyclin A and B) were down-regulated in DU145 and PC3 cells, whereas only cdk2 was down-regulated in PC3 cells. Moreover, the anti-apoptotic Akt, pAKT and Bcl-2 proteins were down-regulated, while the pro-apoptotic protein Bax was up-regulated. CA2 induced anti-metastatic effects by decreasing chemotaxis and cell migration, while it increased cell adhesion to fibronectin and collagen matrix.

CONCLUSION

These results suggest that daucosterol is the major active principle responsible at least in part for the anticancer effect of the extract of Crateva adansonii.

Potential of Regular Consumption of Cameroonian Neem (Azadirachta indica L.) Oil for Prevention of the 7,12-Dimethylbenz(a)anthracene-Induced Breast Cancer in High-Fat/Sucrose-Fed Wistar Rats

Neem (Azadirachta indica) is a tree from the Meliaceae family native to India, where it is considered as one of the most important plants worldwide. The anticancer effects of neem oil on breast cancer cells have been recently reported; however, its in vivo effects have not been studied. This prompted us to investigate the protective effects of neem oil on 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer in high-fat/sucrose-fed Wistar rats. Juvenile female Wistar rats were treated either with neem oil at a dose of 3 mL/kg body weight at 3 different frequencies, 2 times/week (Neem 1), 4 times/week (Neem 2), and every day (Neem 3), or with tamoxifen (3.3 mg/kg body weight), starting 1 week prior to DMBA treatment and lasting 12 weeks. Incidence, burden, volume, and histological analysis of mammary tumors were measured. Further toxicological parameters have been assessed. No tumors were detected in rats from the normal group, while all the rats from the negative control group (100%) developed mammary tumors. The regular consumption of neem oil at a dose of 3 mL/kg (2 or 4 times/week) significantly (p < 0.01) and in a dose-dependent manner reduced tumor incidence (80%), burden [35.78% (2 times/week) and 36.09% (4 times/week)], and weight. Neem consumption protected rats against DMBA-induced breast hyperplasia, with an optimal effect when taken 4 times weekly. Interestingly, all the animals that received a daily dose of 3 mL/kg died at the third week of the experiment. Further, animals that took the neem oil 4 times per week developed hepatotoxicity, evidenced by an increase of liver wet weight, transaminase (ALT and AST) activity, and histological abnormalities in liver. This study brings insight into the use of neem oil, which is greatly appreciated in traditional medicine. In summary, we demonstrated for the first time that the regular consumption of neem oil prevents breast cancer, but its excessive consumption is toxic.

The hydro-ethanolic extract of Acacia seyal (Mimosaceae) stem barks induced death in an ER-negative breast cancer cell line by the intrinsic pathway of apoptosis and inhibited cell migration

BACKGROUND

Despite the significant developments occurring in the treatment of cancer, it still remains the second deadly disease, responsible for 8.2 million deaths every year. Various natural substances have been studied for active molecules of tumor suppression in the past and the tropical flora, by its diversity, continues to provide new antitumor drugs. Acacia seyal is a plant used in Cameroonian traditional system to treat cancer. It exhibited cytotoxic effects towards human breast adenocarcinoma cells. The present work was therefore designed to elucidate the underlying mechanisms by which A. seyal extract induced its cytotoxic effect.

METHODS

The cell death mechanism (apoptosis or necrosis) and cell cycle analyses were assessed using flow cytometry. The levels of reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm), caspases activities as well as Bcl-2 and Bcl-xL protein contents were assessed in MDA-MB-231 cells. Afterwards, cell migration/invasion was also assessed.

RESULTS

The A. seyal extract induced apoptosis in MDA-MB-231 cells, while it failed to do so in MCF-7 cells. It induced cell cycle arrest in G2/M phase. Further it induced a decrease in ΔΨm, an increase in ROS levels and caspases activities as well as a down regulation in Bcl-2 and Bcl-xL protein contents in MDA-MB-231 cells. Moreover, A. seyal extract exhibited anti-migration, anti-invasion activities in MDA-MB-231 cells.

CONCLUSION

These results demonstrate that A. seyal extract induced its antitumor effects mainly by interference in metastasis related events, by triggering apoptosis through a ROS-mediated mitochondrial pathway.

In Vitro Cytotoxicity and In Vivo Antimammary Tumor Effects of the Hydroethanolic Extract of Acacia seyal (Mimosaceae) Stem Bark

The present study was designed to evaluate the in vitro and in vivo antitumor effects of A. seyal hydroethanolic extract on breast cancer. The cytotoxicity of A. seyal extract was evaluated using resazurin reduction assay in 9 cell lines. Further, the protective effect of the hydroethanolic extract of A. seyal stem barks was evaluated on 7,12-dimethylbenz(a)anthracene- (DMBA-) induced breast cancer rat model. Incidence, burden, volume, and histological analysis of mammary tumors were measured. The Acacia seyal extract exhibited CC50 of 100 in MCF-7 cells after 24 h. In vivo, no tumors were detected in rats from the control group, while 11 rats out of 12 (91.66%) developed mammary tumors in the DMBA-exposed group receiving only the vehicle. Acacia seyal extract significantly (p < 0.01) and in the dose-dependent manner reduced tumor incidence (3 rats out of 12 at the dose of 300 mg/kg), burden [62.1% (150 mg/kg) and 65.8% (300 mg/kg)], and mass. It protected rats against DMBA-induced breast hyperplasia, with an optimal effect at the dose of 300 mg/kg. Taken altogether, these results suggest that the hydroethanolic extract of Acacia seyal might contain phytoconstituents endowed with antitumoral properties, which could protect against the breast cancer induced in rats.

Ficus umbellata Vahl. (Moraceae) Stem Bark Extracts Exert Antitumor Activities In Vitro and In Vivo

A Ficus umbellata is used to treat cancer. The present work was therefore designed to assess antitumor potentials of F. umbellata extracts in nine different cell lines. Cell cycle, apoptosis, cell migration/invasion, levels of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), caspases activities as well as Bcl-2 and Bcl-xL protein content were assessed in MDA-MB-231 cells. The 7,12-dimethylbenz(a)anthracene (DMBA)-induced carcinogenesis in rats were also used to investigate antitumor potential of F. umbellata extracts. The F. umbellata methanol extract exhibited a CC50 of 180 μg/mL in MDA-MB-231 cells after 24 h. It induced apoptosis in MCF-7 and MDA-MB-231 cells, while it did not alter their cell cycle phases. Further, it induced a decrease in MMP, an increase in ROS levels and caspases activities as well as a downregulation in Bcl-2 and Bcl-xL protein contents in MDA-MB-231 cells. In vivo, F. umbellata aqueous (200 mg/kg) and methanol (50 mg/kg) extracts significantly (p < 0.001) reduced ovarian tumor incidence (10%), total tumor burden (58% and 46%, respectively), average tumor weight (57.8% and 45.6%, respectively) as compared to DMBA control group. These results suggest antitumor potential of F. umbellata constituents possibly due to apoptosis induction mediated through ROS-dependent mitochondrial pathway.

Anti-inflammatory activity of Crateva adansonii DC on keratinocytes infected by Staphylococcus aureus: From traditional practice to scientific approach using HPTLC-densitometry

ETHNOPHARMACOLIGICAL RELEVANCE

Leaves of Crateva adansonii DC (Capparidaceae), a small bush found in Togo, are widely used in traditional medicine to cure infectious abscesses. Traditional healers of Lomé harvest only budding leaves early in the morning, in specific area in order to prepare their drugs.

AIM OF THE STUDY

The main goal was to validate the ancestral picking practices, and to assess the activity of C. adansonii medicine towards infectious abscesses.

MATERIALS AND METHODS

A phytochemical screening of various C. adansonii leaf samples was performed using an original HPTLC-densitometry protocol and major flavonoids were identified and quantified. C. adansonii samples were collected in different neighborhoods of Lomé, at different harvesting-times and at different ages. Radical scavenging capacity, using DPPH assay, was used to quickly screen all extracts. Extracts were tested for anti-Staphylococcus aureus activity and anti-inflammatory effect on human primary keratinocytes infected by S. aureus. IL6, IL8 and TNFα expression and production were assessed by RT-PCR and ELISA assays.

RESULTS

Using antioxidant activity as selection criteria, optimal extracts were obtained with budding leaves, collected at 5:00am in Djidjolé neighborhood. This extract showed the strongest anti-inflammatory effect on S. aureus-infected keratinocytes by reducing IL6, IL8 and TNFα expression and production. None of the extracts inhibited the growth of S. aureus.

CONCLUSIONS

Those results validate the traditional practices and the potential of C. adansonii as anti-inflammatory drug. Our findings suggest that traditional healers should add to C. adansonii leaves an antibacterial plant of Togo Pharmacopeia, in order to improve abscess healing.

Experimental mammary carcinogenesis - Rat models

Mammary cancer is one of the most common cancers, victimizing more than half a million of women worldwide every year. Despite all the studies in this field, the current therapeutic approaches are not effective and have several devastating effects for patients. In this way, the need to better understand the mammary cancer biopathology and find effective therapies led to the development of several rodent models over years. With this review, the authors intended to provide the readers with an overview of the rat models used to study mammary carcinogenesis, with a special emphasis on chemically-induced models.