Department of Clinical Pharmacy & Pharmacology, School of Pharmacy, Muhimbili University of Health & Allied Sciences, Dar es Salaam, Tanzania; Department of Biological and Pre-clinical Studies, Institute of Traditional Medicine, Muhimbili University of Health & Allied Sciences, Dar es Salaam, Tanzania.
Department of Biological and Pre-clinical Studies, Institute of Traditional Medicine, Muhimbili University of Health & Allied Sciences, Dar es Salaam, Tanzania.
J Ethnopharmacol. 2022 Oct 5;296:115501. doi: 10.1016/j.jep.2022.115501. Epub 2022 Jun 22.
Although the available medicines can cure almost all tuberculosis drug-susceptible patients some problems including the emergence of multi-drug resistant and extensively drug-resistant strains press for the need of new anti-TB medicines. Morella salicifolia is a common plant that is widely used in traditional medicine for managing HIV and AIDS-related conditions including tuberculosis but no studies have been done to evaluate its safety and efficacy.
This study was designed to investigate the antimycobacterial activity and safety of M. salicifolia extract and its constituents.
Antimycobacterial activity of the crude extract was tested against non-pathogenic mycobacteria including Mycobacterium aurum (MA), Mycobacterium indicus pranii (MIP) and Mycobacterium madagascariense (MM) using the broth microdilution method. Bioassay-guided fractionation was employed to isolate the active compounds. Some of the isolated active compounds were tested for antimycobacterial activity against the standard and selected clinical isolates of M. tuberculosis. Safety of the crude extract was assessed using cytotoxicity assay and oral acute toxicity testing.
The crude extract exhibited antimycobacterial activity against all the species used. The study led to isolation of six compounds; four pentacyclic triterpenoids; (3β)-3-Hydroxyolean-12-en-28-oic acid (Oleanolic acid) (1), (2α,3β)-2,3-Dihydroxyolean-12-en-28-oic acid (maslinic acid) (2), D-Friedoolean-14-ene-3β,28-diol (taraxerol) (3), and D-Friedoolean-14-en-3β-ol (myricadiol) (4), and two diarylheptanoids; (±)-myricanol (5) and myricanone (6). The six compounds exhibited activity against three nonpathogenic mycobacteria species. Compound 2, was the most active, with MICs of 17, 28 and 56 μg/ml against MM, standard a M. tuberculosis strain HRV and rifampicin resistant M. tuberculosis clinical isolates, respectively. The crude extract did not show toxicity on peripheral blood mononuclear cells and it was safe in mice following acute oral toxicity test.
The results from this study indicate that some isolated compounds in Morella salicifolia could form potential scaffolds for drug development efforts targeting M. tuberculosis. More studies are needed to further explore the potential of the plant extract and its secondary metabolites in the management of HIV and AIDS-related conditions using in-vivo models.
尽管现有药物几乎可以治愈所有对结核病药物敏感的患者，但包括出现耐多药和广泛耐药菌株在内的一些问题，仍迫切需要新的抗结核药物。杨梅是一种常见的植物，在传统医学中被广泛用于治疗艾滋病毒和艾滋病相关病症，包括结核病，但尚未有研究评估其安全性和疗效。
本研究旨在研究杨梅提取物及其成分的抗分枝杆菌活性和安全性。
采用肉汤微量稀释法检测杨梅粗提取物对非致病性分枝杆菌（包括金黄分枝杆菌（MA）、印度分枝杆菌（MIP）和马达加斯加分枝杆菌（MM））的抗分枝杆菌活性。采用生物活性导向分离法分离活性化合物。对一些分离出的活性化合物进行了抗结核分枝杆菌标准株和选定临床分离株的活性试验。采用细胞毒性试验和口服急性毒性试验评估粗提取物的安全性。
粗提取物对所用的所有种均具有抗分枝杆菌活性。研究导致了六种化合物的分离；四种五环三萜；（3β）-3-羟基齐墩果酸（齐墩果酸）（1）、（2α，3β）-2,3-二羟基齐墩果酸（马桑酸）（2）、D-降佛烯-14-烯-3β,28-二醇（蒲公英醇）（3）和 D-降佛烯-14-烯-3β-醇（杨梅醇）（4），和两种二芳基庚烷；（±）-杨梅醇（5）和杨梅酮（6）。六种化合物对三种非致病性分枝杆菌种均有活性。化合物 2 对 MM、标准的结核分枝杆菌 HRV 株和利福平耐药结核分枝杆菌临床分离株的 MIC 分别为 17、28 和 56μg/ml。粗提取物对外周血单核细胞无毒性，经急性口服毒性试验后在小鼠中安全。
本研究结果表明，杨梅中分离的一些化合物可能成为针对结核分枝杆菌的药物开发的潜在支架。需要进一步研究植物提取物及其次生代谢物在艾滋病毒和艾滋病相关病症管理中的潜力，采用体内模型。
