From diarrhoeal disease to tuberculosis: A jump in application of phytomedicines
In 2002, the Foundation initiated research on the evaluation of medicinal plants, the prime aim being the application of the research on plants for primary health care use by resource-poor communities. Diverting from the conventional approach of utilizing the plants mainly for their antimicrobial activity, the Foundation has been instrumental in developing an innovative approach to assaying the medicinal plants by targeting different stages of host-parasite interaction, in lieu of direct killing of the bacteria. This approach was initially used for studies on diarrhoeal diseases, including antibiotic resistant diarrhoea and later for tuberculosis.
The work on medicinal plants at FMR demonstrated a pathway towards development of phytomedicines right from systematic selection of the plant to conducting a proof of concept effectiveness trial in humans. Ethnobotanical survey followed by preclinical screening indicated guava leaf extract (Psidium guajava) to be effective in controlling diarrhoea caused by different microorganisms. In addition, due to the varied mechanisms of action, it can work at different stages of the disease process and the possible synergistic action of its components may prevent the development of resistance. Subsequent work in the last decade with P. guajava included a proof-of-concept clinical trial and metabolomics to standardize crude extract on the other. Additionally, the efficacy of guava extract against antibiotic resistant bacteria was also explored, wherein ability of P. guajava to limit bacterial growth and/or quorum-sensing (QS) regulated pigment production of selected antibiotic resistant bacteria in vitro and using in vivo Caenorhabditis elegans model revealed its ability to inhibit antibiotic resistant bacteria too.
We now aim to amalgamate phytomedicine with our expertise on tuberculosis (TB), an area we have been actively working for over two decades. We plan to focus on development of novel phytomedicine-based therapeutic strategies for TB by targeting unique, non-canonical DNA structures within the Mycobacterium tuberculosis genome for control of their growth. Our approach is distinct and novel from traditional TB drug development, which often focuses on proteins or enzymes. By targeting DNA, we investigate a hitherto unexplored method of therapeutic intervention. G-quadruplexes, have been demonstrated to play important roles in various biological processes, making them prospective targets for new anti-TB drugs. The potential impact of this research is significant offering hope for targeted treatments in TB.
Some key highlights of our research in this area are
- Exploration of plants for primary health care for use by resource poor communities.
- Distinct from the conventional approach of utilizing plants for their antimicrobial activity (direct killing of the bacteria), the Foundation’s work has been instrumental in developing an innovative approach using multiple assays to target different stages of host-parasite interaction.
- Provided inputs for a blueprint for an integrated institute of traditional medicine in Pasighat, Arunachal Pradesh on invitation from AYUSH, Government of India and for developing a road-map for combating antimicrobial resistance on request by the World Health Organization.
- Underlined the challenges in crude extract standardization and the need for policies to attract investment by the industry
- Explored medicinal plants for minimizing the development of drug resistance
- Demonstrated guava leaves as potent anti-diarrhoeal through pre-clinical screening & proof of concept clinical trial.
- Through guava leaf research, a road map has been developed for modernization and wider acceptance of traditional plant-based medicines. This highlights the importance of multi modal pre-clinical screening of plants and standardization of crude extracts through metabolomics.
PROJECTS
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Principal Investigator
Dr. Tannaz Birdi
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Collaborators
Drs. Ragini Macaden, Mary Dias, St. John's Research Institute, Bengaluru
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Project Team
Ms. Poonam Daswani, Mr. Vigneshwaran Muthuraman
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Funded by
Zoetis Pharmaceutical Research Private Limited
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Duration
December 2018– February 2020
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Budget
INR 24.10 lakhs
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Status
Completed
ABOUT THE PROJECT
In all the previous work related to anti-diarrhoeal medicinal plants undertaken by the Foundation, the bacterial strains used were standard laboratory strains. With increasing reports on antimicrobial resistance amongst diarrhoeal pathogens, this study explored the use of guava leaf decoction (GLD) for treatment of antibiotic resistant diarrhoeal pathogens. Antibiotic resistant clinical isolates of Shigella spps. were used as increasing reports of antibiotic resistance is reported involving this spps. and alternative approaches are needed to combat Shigellosis. In the present study, GLD was tested for its bactericidal action and effect on bacterial invasion of epithelial cells. Antibiotic clinical isolates were provided by St. John’s Hospital, Bengaluru, and Hinduja Hospital, Mumbai.
KEY FINDINGS/ACHIEVEMENTS
- Amongst the 43 Shigella isolates included in the study, GLD affected the growth of 23 strains. The invasion of nine strains from the 20 remaining resistant isolates was unaffected.
- In comparison to other spps. (sonnei, boydi, dysentriae), isolates belonging to S. flexneri serogroup were more sensitive to GLD.
- The study revealed the efficacy of GLD against drug resistant Shigella spps. and could be considered for the treatment of diarrhoea. The approach can be a cost-effective alternative to antibiotics.
PUBLICATION
- Daswani, P., Vigneshwaran, M., Macaden, R., Dias, M. & Birdi, T. (2021). Effect of Psidium guajava (guava) L. leaf decoction on antibiotic resistant clinical diarrhoeagenic isolates of Shigella spps. International J Enteric Pathogens, 8: 122-129.
PRESENTATION
- Birdi, T. Use of botanicals for combating antibiotic-resistant pathogens. Invited Talk, organized by PREVENT IT and Chitakara University, Punjab, December 2020.
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Principal Investigator
Dr. Tannaz Birdi
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Project Team
Dr. Manasi Gholkar, Dr. Vidhya Iyer, Ms. Poonam Daswani
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Funded by
Zoetis Pharmaceutical Research Private Limited
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Duration
December 2018 – August 2019
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Budget
INR 7.00 lakhs
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Status
Completed
About the Project
Due to the cost involved as well as limited availability of high-end nuclear magnetic resonance (NMR), its use for standardization of crude plant extracts is limited. Additionally, individual compounds could not be identified based on the NMR peaks identified. Hence this project was extended to explore the use of HPLC, which is relatively cheaper and widely available. The guava batches and the biological data of the earlier project remained the same. Similar mathematical models too were used for correlating the biological activity of guava leaf with HPLC profiles to identify key peaks responsible for the anti-diarrhoeal activity.
KEY FINDINGS/ACHIEVEMENTS
- Good differentiation of extracts based on seasonal and regional variation was seen.
- Successful models could be established for all eight bioassays.
- Though no peaks could be correlated with the biological assays, it is possible that further analysis can provide information on compounds of interest.
PUBLICATION
- Gholkar, M.S., Daswani, P.G. Iyer, V. & Birdi, T.J. (2021). High performance liquid chromatography-based metabolomics of Psidium guajava Linn. leaf extracts.bioRxiv 2022.01.25.477015.Preprint
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Principal Investigator
Dr. Tannaz Birdi
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Collaborator
Dr. Jia Li, Imperial College London
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Project Team
Dr. Manasi Gholkar, Ms. Poonam Daswani (FMR)
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Funded by
Zoetis Pharmaceutical Research Private Limited
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Duration
August 2016 – December 2018
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Budget
INR 48.00 lakhs
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Status
Completed
About the Project
The acceptability of traditional medicine by modern practitioners is low, often due to a lack of standardization of raw material/ extracts resulting in extreme variability in efficacy. This is because medicinal plant preparations are chemically complex and synergy between compounds is often present. Also variability in the chemical composition due to environmental factors necessitates standardization. Difficulties in extract standardization arise due to (i) unknown active principles; (ii) synergy between two or more compounds. Hence a common approach is to standardize extracts on the basis of quantification of one or more marker compounds. However, despite the presence of marker compounds, there can be wide variations in the biological activities due to unknown active principles.
The wide variations in the efficacy of botanicals have necessitated their standardization using modern techniques. Presently in the absence of high throughput assays, standardization involves cumbersome biological assays which are impractical for industry. Nuclear Magnetic Resonance (NMR) has the advantage of providing comprehensive information in a single analysis. Additionally, NMR has advantages such as reproducibility and minimal sample preparation. Thus, in this study, metabolomic studies involving NMR spectral analysis were undertaken. Through proton NMR (1H NMR) an attempt was made to recognize key peaks which together would comprise of a spectral fingerprint relating to the efficacy of Psidium guajava (guava) leaf extract wherein a number of unidentified active principles are involved. Using different mathematical models (Regression or Orthogonal Partial Least Square-Discriminant Analysis (OPLS-DA), the biological activity of guava leaf (90 batches collected from different regions in various seasons were included in the study) was correlated with the NMR spectra to identify key peaks responsible for the anti-diarrhoeal activity. It was proposed that important peaks could later be used as markers of efficacy.
KEY FINDINGS/ACHIEVEMENTS
- OPLS-DA showed a clear seasonal and regional segregation of extracts.
- Significant models were established for seven bioassays, namely anti-bacterial activity against Shigella flexneri and Vibrio cholerae, adherence of E. coli, invasion of E. coli and S. flexneri and production and binding of toxin produced by V. cholerae.
- It was observed that none of the extracts was uniformly good or bad across all the bioassays. The spectral analysis showed multiple peaks correlating with a particular activity.
- It was noted that the extracts contained quercetin, ferulic acid and gallic acid. However, they did not correlate with the peaks that segregated extracts with good and poor activity.
- The approach used is among the few attempts reported to standardize crude plant extracts which would assist in the modernization and wider acceptance of traditional remedies. The spectral fingerprinting employed in the present study can be used as a prototype for standardization of plant extracts with respect to efficacy.
PUBLICATION
- Gholkar, M.S., Li, J.V., Daswani, P.G. Tetali, P. & Birdi, T.J. (2021). 1H nuclear magnetic resonance - based metabolite profiling of guava leaf extract: An attempt to develop a prototype for standardization of plant extracts. BMC Complementary Medicine and Therapies, 21: 1-20.
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Principal Investigator
Dr. Tannaz Birdi
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Collaborator
Drs. Geetha Krishnan, SushilaKataria, Medanta, The Medicity, Gurugram
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Project Team
Dr. Manasi Gholkar, Ms. Poonam Daswani
Dr. Sarita Suhag, Mr. Ankit Goswami, Ms. Himanshi Saini (Medanta, Gurugram)
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Funded by
Rajiv Gandhi Science & Technology Commission
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Duration
February 2016 – May 2018
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Budget
INR 63.13 lakhs
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Status
Completed
ABOUT THE PROJECT
Based on previous studies undertaken at the Foundation, guava (Psidium guajava) leaf decoction (GLD) was identified as a promising anti-diarrhoeal plant. This study was a proof of concept clinical trial to validate the efficacy of guava leaf decoction for treating adults with uncomplicated diarrhoea. Additionally, the determination of an efficacious dose and evaluation of the safety of the decoction was also undertaken.
The trial was an open efficacy randomized 5-day, parallel group multi-arm interventional study in collaboration with Department of Integrative Medicine, Medanta Hospital, Gurgaon where the trial was undertaken. The department is well recognized and experienced in treating patients with various ailments and in conducting clinical trials in an integrated manner.Amongst 137 adults (18-60 years) suffering from acute diarrhoea, 109 were included. Three doses of GLD (6-leaf, 10-leaf and 14-leaf) were compared with controls receiving oral rehydration solution. A decrease in stool frequency and improvement in consistency were the outcomes measured.
KEY FINDINGS/ACHIEVEMENTS
- The study validated the laboratory research previously undertaken with GLD
- The trial showed that the 14-leaf (7.4 g) decoction was the most effective. Administration of the decoction thrice daily helped the patients regain normalcy in 72 hours as opposed to 120 hours in controls
- Safety of the intervention was reflected by normal levels of haemoglobin, liver and kidney parameters in patients taking the decoction
- No adverse events were reported.
- In healthy volunteers, consumption of decoction for the same period as the patients did not lead to constipation
Encouraged by the clinical findings, another proposed exploratory pilot clinical trial is being proposed. This study aims to explore if guava leaf extract can help alleviate microbial perturbations in the gut and lung due to tuberculosis and potentially improve clinical outcomes (submitted to Ekhagastiftelsen Foundation, Sweden in May 2022).
PUBLICATION
- Birdi, T.J., Krishnan, G., Kataria, S., Gholkar, M. & Daswani, P. (2020). A randomized open label efficacy clinical trial of oral guava leaf decoction in patients with acute infectious diarrhea. Journal of Ayurveda and Integrative Medicine,11: 163-172.
CONFERENCE PRESENTATIONS
- Birdi, T. Documenting the efficacy of guava (Psidium guajava) leaf decoction for treating patients with diarrhea. Oral Presentation. Seminar on ‘Innovations in the food processing industry: Technology available for transfer organized’ organized by Maratha Chamber of Commerce, Industries & Agriculture, Pune, 20th September, 2019.
- Gholkar, M. Documenting the efficacy of guava (Psidium guajava) leaf decoction for treating patients with diarrhoea. Poster Presentation. India International Science Festival organized by Ministry of Science & Technology, Ministry Earth Science, Dept. of Biotechnology, Vijnana Bhavan, Govt. of UP, National institute of Immunology, Lucknow, 5th -8th October 2018.