期刊
FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY
卷 12, 期 -, 页码 -出版社
FRONTIERS MEDIA SA
DOI: 10.3389/fcimb.2022.1063407
关键词
malaria; antimalarial; azithromycin; quick-killing; Plasmodium
资金
- National Health and Medical Research Council of Australia [1143974, 1113712, 1148700]
- Victorian State Government
- Australian Government NHMRC IRIISS
- NHMRC [1173046]
- ARC-RTP scholarship
- NIH [U2C-DK119886]
This study evaluated azithromycin analogues and found that they improved quick-killing activity against Plasmodium falciparum and Plasmodium knowlesi parasites. These analogues not only maintained activity, but also had higher selectivity against P. falciparum compared to human cells. The quick-killing activity of these drugs was achieved by inhibiting bacterium-like ribosomes or the apicoplast, and their activity did not improve in other related parasites and bacteria. This research provides new starting points for developing azithromycin analogues with quick-killing antimalarial activity.
IntroductionThe spread of artemisinin resistant Plasmodium falciparum parasites is of global concern and highlights the need to identify new antimalarials for future treatments. Azithromycin, a macrolide antibiotic used clinically against malaria, kills parasites via two mechanisms: 'delayed death' by inhibiting the bacterium-like ribosomes of the apicoplast, and 'quick-killing' that kills rapidly across the entire blood stage development. MethodsHere, 22 azithromycin analogues were explored for delayed death and quick-killing activities against P. falciparum (the most virulent human malaria) and P. knowlesi (a monkey parasite that frequently infects humans). ResultsSeventeen analogues showed improved quick-killing against both Plasmodium species, with up to 38 to 20-fold higher potency over azithromycin after less than 48 or 28 hours of treatment for P. falciparum and P. knowlesi, respectively. Quick-killing analogues maintained activity throughout the blood stage lifecycle, including ring stages of P. falciparum parasites (<12 hrs treatment) and were >5-fold more selective against P. falciparum than human cells. Isopentenyl pyrophosphate supplemented parasites that lacked an apicoplast were equally sensitive to quick-killing analogues, confirming that the quick killing activity of these drugs was not directed at the apicoplast. Further, activity against the related apicoplast containing parasite Toxoplasma gondii and the gram-positive bacterium Streptococcus pneumoniae did not show improvement over azithromycin, highlighting the specific improvement in antimalarial quick-killing activity. Metabolomic profiling of parasites subjected to the most potent compound showed a build-up of non-haemoglobin derived peptides that was similar to chloroquine, while also exhibiting accumulation of haemoglobin-derived peptides that was absent for chloroquine treatment. DiscussionThe azithromycin analogues characterised in this study expand the structural diversity over previously reported quick-killing compounds and provide new starting points to develop azithromycin analogues with quick-killing antimalarial activity.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据