Name: Linous Munsimbwe
Affiliation: Research Unit for Advanced Preventive Medicine
Position: Foreign Visiting Researcher
Term: Jun. to Aug. 2019
Host researcher: Assistant Professor Keisuke Suganuma (English /Japanese)
Circumstances of application:
I applied as a Visiting Foreign Researcher because NRCPD is an OIE reference center for Surra and Bovine Babesiosis and Equine and having trained at the center in 2012-2013, I have come to understand why the center was chosen to be a reference center.
- NRCPD has a strong and dedicated staff that are committed to delivering excellent results. The education and research offered at NRCPD is focused on knowledge and technologies that can help solving global problems in the fields of veterinary science.
- NRCPD plays a bigger role at developing individuals who can contribute significantly at international level using modern research technologies to address and resolve various challenges related to animal disease control and food safety.
- NRCPD is a very conduce center for learning and developing graduates and researchers who are internationally minded and have practical knowledge and skills.
- NRCPD is well established as a center of academic research contributing to sustainable development and application of the results of creative and practical studies.
Therefore, I wanted to challenge myself to conducting research on protozoan diseases at NRCPD again.
Research activity in NRCPD:
The objective of the research was:
- To evaluate the trypanocidal activity of Cassia abbreviata, a herbal plant extract from Chibombo district, Central Province of Zambia on different types of trypanosomes and determine the cytotoxicity and inhibition concentrations.
- To evaluate the trypanocidal activity of the South African compounds on different types of trypanosomes and determine the cytotoxicity and inhibition concentrations and determine the cytotoxicity and inhibition concentrations.
NRCPD Activities:
- Maintained of trypanosomes blood stream form cultures of Trypanosoma brucei brucei GuTat3.1, Trypanosoma brucei rhodesiense IL1923, Trypanosoma brucei rhodesiense Chirundu (Zambia isolate), Trypanosoma brucei gambiense IL2343, Trypanosoma evansi Tansui and Trypanosoma congolense IL3000.
- Conduct in vitro screening of South African compounds
- Conduct in vitro screening of Cassia abbreviata compounds from Zambia
- Purification and identification of components in Cassia abbreviata (in collaboration with Tohoku Medical and Pharmaceutical University, Sendai)
- Carry out Laboratory and general Cleaning Maintenance
- Mice Handling
Results:
Results:
C.abbreviata bark extraction and synthesis process yielded a number of compounds and derivatives. Others are yet to be identified. From the C. abbreviata bark crude extracts (CA#1), a further 16 fractions were extracted which included water fraction of the bark (CA#6) and its 6 crude derivatives (CA#9-#14), ether fraction of the bark (CA#7) and its 4 crude derivatives (CA#15-18) and methanol fraction of the bark (CA#8) and its 6 fractions (CA#9-14). CA#11 (fraction 3 from CA#6), was further purified to give Fractions Fr.18A-Fr.18N (CA#25-37), n=13. Others from Fr.18D and Fr.18E (CA#38, CA#39 and CA#44) n=3, and from Fr18F (CA#40-43 and CA#45-47) n=7, giving a total of 23 pure compounds.
The crude bark extract, fractions and compounds had potent activity against the 6 Trypanosoma species. Six compounds of C. abbreviata exhibited strong trypanocidal activity against Trypanosoma Species. Further synthesis and analysis of ether soluble fractions will be conducted during the first quarter of 2020 at Tohoku Medical and Pharmaceutical University in Sendai.
As for the South African compounds, 4 compounds showed good trypanocidal activity and selectivity index. These will be good candidates for the further analyses, especially against some Trypanosoma species. These compounds showed Trypanocidal activities.
Future prospects:
Further analysis of ether soluble fractions will be conducted during the first quarter of 2020 at Tohoku Medical and Pharmaceutical University in Sendai.
My field of study is trypanosomosis control and having carried out research at NRCPD in I feel I have acquired enough knowledge in diversity for future prospects. This is because I have further developed myself for new challenges that are created by the outbreak and expansion of zoonotic diseases such as trypanosomiasis for which I have now better understand of the research methodologies and techniques.
As a university lecturer I have acquired extra knowledge and techniques to address new ways to diagnose and combat diseases, and train my students for the challenges that lay ahead. I have been adequately prepared as a Researcher, Lecturer and Head of Veterinary Public Health to improve my staff and students, build up momentum and capacity to address the disease control demands, initiate new staff trainings, start new research projects, and find innovative approaches to improve livestock health. I feel NRCPD has filled in that gap perfectly and is an important step in reaching my goals and the Government goals.
I would like to sincerely thank my supervisors Assistant Professor Keisuke Suganuma and Professor Shin-ichiro Kawazu, National Research Center for Protozoan Diseases for the advice, guidance and encouragement rendered during my research. They were my mentors and great committed researchers I have ever known.
I would also like to thank the members of the Mosquito and Vaccine Laboratory, Research Unit for Advanced Preventive Medicine and all the staff of NRCPD for the wonderful relationship that we created and for facilitating my wonderful stay in Japan.