Asian Pacific Journal of Tropical Biomedicine

280–287

Authors: Nugroho Trilaksana, Ignatius Riwanto, Raymond Rubianto Tjandrawinata, Reki Winarto

Objective: To prove the molecular mechanisms of Mahkota Dewa (Phaleria macrocarpa) in suppressing proliferation of human retinoblastoma cells through suppression of cell cycle's gene-regulators expression. Methods: In this study, the molecular mechanism of anti-tumor effect of fractioned extract of Phaleria macrocarpa (DLBS1425) in human retinoblastoma cells Y-79 was investigated by measuring the tumor cells viability, the assessment of population profiles of tumor cells in the cell cycle, and the mRNA concentration of p16, p21, p53, cyclin D, cyclin E, and E2F. Results: DLBS1425 showed an inhibition effects towards proliferation of Y-79 cell line. Inhibition of proliferation was shown by suppression of cell cycle progression. DLBS1425 downregulated cyclin E, a G1 phase regulator gene of cell cycle, in dosedependent manner without affecting p53–p21 pathway. In the other word, DLBS1425 inhibits cell proliferation through suppression of cyclin E independently towards conventional proliferation pathway. Conclusions: Our results suggest that DLBS1425 is a potential anticancer agent which targets genes involved in cell proliferation in human retinoblastoma cells which make it pharmacologically ideal for the prevention and/or treatment of retinoblastoma cancer.

294–299

Authors: Md. Quamrul Hassan, Mohd. Akhtar, Sayeed Ahmed, Aftab Ahmad, Abul Kalam Najmi

Objective: To evaluate the cardioprotective effect of Nigella sativa L. (N. sativa) in isoproterenol-induced myocardial infarction (MI). Methods: Groups were treated with different doses of ethanol extract of N. sativa (EENS) and N. sativa oil alone and along with enalapril for 28 days. MI was induced by subcutaneous administration of isoproterenol (85 mg/kg) in two consecutive doses. Levels of cardiac biomarkers and antioxidant enzymes such as creatine kinase–N-acetyl-L-cysteine, lactate dehydrogenase, aspartate aminotransferase, malondialdehyde, superoxide dismutase, reduced glutathione and catalase were evaluated along with gross histopathological examination. Results: Isoproterenol (85 mg/kg) induced MI by causing the significant (P < 0.01) reduction in the activity of cardiac biomarkers (creatine kinase–N-acetyl-L-cysteine, lactate dehydrogenase, aspartate aminotransferase) and antioxidant markers (superoxide dismutase, catalase, glutathione) along with significant (P < 0.01) increase in the level of malondialdehyde. Furthermore, histopathological evaluation also confirmed the isoproterenol-induced MI. Pretreatment with EENS (800 mg/kg) and combination of EENS (800 mg/kg) with enalapril (1 mg/kg) significantly (P < 0.01) prevented the development of these alteration and restored activity of cardiac biomarkers as well as antioxidant markers almost near to normal levels. Histopathological evaluation of cardiac tissue further confirmed the restoration of biochemical activity. Conclusions: Experimental findings thus indicate that EENS (800 mg/kg) demonstrated cardioprotective effect against isoproterenol-induced MI by restoring cardiac biomarkers and antioxidant status.

306–313

Authors: Taiwo Adesola Akinyele, Etinosa Ogbomoede Igbinosa, David Ayinde Akinpelu, Anthony Ifeanyin Okoh

Objective: To evaluate the interactions between the crude extracts of Cocos nucifera (C. nucifera) and six front line antibiotics (ampicillin sodium salt, penicillin G sodium, amoxicillin, chloramphenicol, ciprofloxacin and tetracycline hydrochloride), against some bacterial pathogens linked with human infection. Methods: The pulverized husk of C. nucifera was dissolved in 95% n-hexane and extracted using Soxhlet extraction method and sterile distilled water (aqueous). The antibacterial susceptibility of the crude extracts of C. nucifera was tested against environmental and clinical strains (6) obtained from the South African Bureau of Standards (SABS), Vibrio (6) and Listeria pathogens (6). The agar-well diffusion method was used for screening the extracts for their antibacterial activity. The minimum inhibitory concentration and minimum bactericidal concentration of the extracts were determined. Time-kill assay was used to evaluate bactericidal and/or bacteriostatic activity. The synergistic effect of the crude extracts and antibiotics was assessed and evaluated by adopting the checkerboard methods. Results: With the time-kill assay, the highest bactericidal activity was observed on Vibrio fluvialis EL041 with a −5.6 ± 0.2 log10 CFU/mL decrease in cell density as a result of the combination of the extracts and chloramphenicol at two-fold minimum inhibitory concentrations. Synergisms using the time-kill assay constituted about 72%, while indifference constituted about 28%. The checkerboard method revealed synergistic interaction in 67% of the combinations, and indifference in 33%. There was no specificity in the observed synergy to a particular class of antibiotics. Conclusions: This investigation suggests the crude extracts of C. nucifera to be a potential broad spectrum antimicrobial compound. Therefore, further study is needed to isolate the pure compounds from these crude extracts.

321–331

Authors: Radia Belkhelfa-Slimani, Bahia Djerdjouri

Objective: To investigate the leishmanicidal effects of two antioxidants, caffeic acid and quercetin on Leishmania major (L. major) promastigotes in vitro, and their immunomodulatory effects on infected phagocytes derived from susceptible BALB/c mice. Methods: Caffeicacidand quercetin-inducedcelldeath was examinedbyPi-Hoechst double staining of L. major promastigotes and MTT assay, in the presence or absence of protease inhibitors in vitro. Caffeic acid or quercetin were administered subcutaneously to BALB/c mice infected with L. major promastigotes through a dorsal air pouch. Nitric oxide and superoxide anion production by phagocytes infiltrating the air pouch and the expression of induciblenitricoxidesynthase(iNOS),tumornecrosis factoralpha(TNF-a) and nuclearfactor kappa B in the air pouch membrane were therefore evaluated using appropriate methods. Results: Caffeic acid and quercetin displayed a dose-dependent cytotoxic effect against L. major promastigotes, and induced cell death via caspases-independent pathways. In vivo, L. major promastigotes inoculation into air pouch cavity of BALB/c mice leads to a sequential influx of neutrophils (hours), followed by macrophages (days). Results showed that L. major delayed apoptosis of infected neutrophils and macrophages by the cleavage of the nuclear factor kappa B p65RelA subunit, and persisted by inhibiting TNF-a and iNOS expression and reactive oxygen species generation. Caffeic acid or quercetin restored reactive oxygen species production and TNF-a-induced iNOS activity, and abrogate apoptosis delay of infected phagocytes. Conclusions: The leishmanicidal effect of caffeic acid and quercetin on promastigotes and amastigotes, as well as reactivation of infected phagocytes apoptosis, suggested a potential therapeutic role against cutaneous leishmaniasis.

339–346

Authors: Widad Makhdour Al-Bishri, Eman Salah Abdel-Reheim, Amr Reda Zaki

Objective: To investigate the protective effect of purslane with carbamazepine treatment. Methods: Male albino rats were modulated by pilocarpine to be epileptic. Both the normal and epileptic rats were treated with carbamazepine, purslane or carbamazepine plus purslane, with separate non-treated control groups for both normal and epileptic rats. Results: The data from the current study showed amelioration in amino acids and electrolytes in the epileptic rats treated with purslane and carbamazepine, with this amelioration occurring without decreasing the fertility hormones (testosterone, dehydroepiandrosterone, luteinizing hormone and follicle stimulating hormone). Purslane treatments also prevented the increase in estradiol. The decreased epileptic hyperexcitability with purslane was evidenced by decreased glial fibrillary acidic protein and lipid peroxidation. Conclusions: Natural products like purslane could be used with the highly repetitive drugs like carbamazepine to reduce or prevent its side-effects.

352–357

Authors: Yead Morshed Nibir, Ahmed Faisal Sumit, Anwarul Azim Akhand, Nazmul Ahsan, Mohammad Shahnoor Hossain*

Objective: To determine the total polyphenol content, antioxidant activity and antibacterial properties of the extracts of different Bangladeshi tea varieties such as flowery broken orange pekoe, broken orange pekoe, red dust and green tea. Methods: Total phenolic and flavonoid contents were determined by Folin–Ciocalteu and aluminum chloride colorimetric assay, respectively. The antioxidant capacity was determined by ferric ion reducing antioxidant power and phosphomolybdenum method. Antibacterial activity was evaluated by disc diffusion method in agar plate and subsequently, the minimum inhibitory concentration was determined by broth dilution method. Results: Total phenolic and flavonoid contents were significantly higher (P < 0.05) in green tea compared to other three black tea varieties. The green tea also showed a higher free radical scavenging and antioxidant activities than all the other tea varieties tested (P < 0.05). In addition, the extracts of all four tea varieties showed inhibitory activity against several pathogenic bacteria and also the same trend of higher antimicrobial activity of green tea than other tea varieties was observed. Conclusions: Taken together, the results of this study demonstrated that Bangladeshi tea, especially the green tea, may act as a substitute for natural antioxidants and as a promising antibacterial agent for beneficial influence in human health.

367–372

Authors: Hossein Masoumbeigi1, Hamid Reza Tavakoli1, Valiollah Koohdar2, Zohreh Mashak2*, Ghader Qanizadeh

Objective: To investigate the environmental influences on the bacteriological quality of red and chicken meats on fridges. Methods: The environmental health status was determined by reliable and valid researcher-made checklist. Then 264 samples were gathered in two phases (at the entrance and three months later) and examined for total bacteria count, Escherichia coli, Staphylococcus aureus and Salmonella spp. Results: The result revealed that the mean of total bacteria count, E. coli and S. aureus densities had significant differences in two steps on chicken and the red meat samples (P < 0.05). Among the environmental factors, sanitary status, temperature and personal hygiene had significant effects on total bacteria count and S. aureus densities in chicken samples (P < 0.05), and between wastewater and solid waste disposal with E. coli density in red meat samples (P < 0.05). Conclusions: The results implied that the bacteriological quality of red and chicken meat fluctuates with environmental status (especially temperature, sanitary status and personal hygiene). Regular control, improving of sanitary health, and staff training are necessary for elimination of bacterial contamination.

378–384

Authors: Arunrat Chaveerach1,2*, Runglawan Sudmoon2,3, Tawatchai Tanee

Developments of drugs or natural products from plants are possibly made, simple to use and lower cost than modern drugs. The development processes can be started with studying local wisdom and literature reviews to choose the plants which have long been used in diverse areas, such as foods, traditional medicine, fragrances and seasonings. Then those data will be associated with scientific researches, namely plant collection and identification, phytochemical screening by gas chromatography-mass spectrometry, pharmacological study/review for their functions, and finally safety and efficiency tests in human. For safety testing, in vitro cell toxicity by cell viability assessment and in vitro testing of DNA breaks by the comet assay in human peripheral blood mononuclear cells can be performed. When active chemicals and functions containing plants were chosen with safety and efficacy for human uses, then, the potential medicinal natural products will be produced. Based on these procedures, the producing cost will be cheaper and the products can be evaluated for their clinical properties. Thus, the best and lowest-priced medicines and natural products can be distributed worldwide.