Rosmarinic acid and its derivative's duel as antitubercular agents: insights from computational prediction to functional response in vitro

Tuberculosis is one of the most dreadful infectious diseases, afflicting global populations with anguish. With the emergence of multi-drug resistant strains of mycobacteria, the imperative for new anti-tuberculosis drugs has grown exponentially. Thus, the current study delves into evaluating the impact of Perovskia abrotanoides and its active metabolites-namely, rosmarinic acid and its derivatives-against strains of Mycobacterium tuberculosis (Mtb). Through the use of the CRI assay, the antimycobacterial potential of the high-altitude medicinal plant P. abrotanoides was gauged, while docking and molecular dynamics simulations unveiled plausible targets. Of these, the peak antimycobacterial effectiveness was observed in the P. abrotanoides ethyl acetate extract with 125 µg/mL as minimum inhibitory concentration against various strains of M. tuberculosis, encompassing H37Rv and strains resistant to multiple drugs. Following bioassay-guided fractionation and isolation, rosmarinic acid and rosmarinic acid methyl ester emerged as potent molecules against H37Rv and multidrug-resistant M. tuberculosis strains; minimum inhibitory concentration ranging from 15 to 32 µg/mL. Additionally, out of 22 targets explored, Mtb lipoamide dehydrogenase (PDB: 3II4) and Rv2623 (PDB: 3CIS) were forecasted as potential Mtb targets for rosmarinic acid and rosmarinic acid methyl ester, respectively, a supposition further affirmed by molecular simulations (100 ns). The stability of both complexes throughout the simulation was measured by protein backbone root-mean-square deviation, substantiating their roles as respective targets for antimycobacterial activities.Communicated by Ramaswamy H. Sarma.

Perovskanol, a new sesquiterpenoid with an unprecedented skeleton from Perovskia Abrotanoides

Phytochemical investigation of the aerial parts of Perovskia abrotanoides (Lamiaceae) by normal phase column chromatography resulted in the isolation of perovskanol (1), a novel sesquiterpenoid possessing a 5/7/5 fused carbon ring skeleton. The structure of 1 was established by comprehensive spectroscopic data analysis including 1 D and 2 D NMR and HRESIMS. The antiprotozoal activity of compound 1 was evaluated against Trypanosoma brucei rhodesiense, T. cruzi, Leishmania donovani, Plasmodium falciparum and no promising activities were shown against all parasite tested.

(Lamiaceae) Populations Based on ISSRs Markers and Essential Oils Profile

Genetic and the essential oil composition variability among twelve Perovskia abrotanoides populations (PAbPs) growing wild in Iran were assessed by ISSR markers, GC-FID and GC/MS, respectively. Nine selected ISSR primers produced 119 discernible bands, of them 96 (80.7%) being polymorphic. Genetic similarity values among populations ranged between 0.07 and 0.79 which indicated a high level of genetic variation. Polymorphic information content, resolving power and marker index generated by ISSR primers were, 0.31, 6.14, and 3.32, respectively. UPGMA grouped PAbPs into four main clusters. Altogether, 38 chemical compounds were identified in the oils, and a relatively high variation in their contents was found. Camphor (11.9 - 27.5%), 1,8-cineole (11.3 - 21.3%), α-bisabolol (0.0 - 13.1%), α-pinene (5.9 - 10.8%), and δ-3-carene (0.1 - 10.5%) were the major compounds. Oxygenated monoterpenes (32.1 - 35.8%) and monoterpene hydrocarbons (25.7 - 30.4%) were the main groups of compounds in the oils studied. Cluster analysis and principal-component analysis were used to characterize the samples according to oil components. Four main chemotypes were found to be Chemotype I (camphor/1,8-cineol), Chemotype II (1,8-cineole/camphor), Chemotype III (camphor/1,8-cineol/α-bisabolol), and Chemotype IV (camphor/δ-3-carene/α-bisabolol). The information, provided here on P. abrotanoides populations, will be useful to introduce this plant into agricultural systems.

on pentobarbital-induced sleep

OBJECTIVE

Sleeplessness is the most common sleep disorder. In this study the hypnotic effect of the hydro-alcoholic extract (HAE) of Perovskia abrotanoides Karel. and its water fraction (WF), ethyl acetate fraction (EAF) and n-butanol fraction (NBF) were studied in mice.

MATERIALS AND METHODS

The test compounds were administered intraperitoneally to mice 30 min before the administration of sodium pentobarbital (30 mg/kg.). Moreover, the influence of flumazenil on the hypnotic effect of the extracts was evaluated. Besides, 30 min after administration of HAE, motor coordination (rota-rod test) was assessed. Additionally, LD50 for HAE was determined and the possible neurotoxicity of the extract was tested in neural PC12 cells.

RESULTS

The HAE and NBF decreased the latency of sleep (p<0.05), and significantly increased the duration of sleep (p<0.05) induced by pentobarbital. These effects of P. abrotanoides were reversed by flumazenil. HAE did not affect the animals' performance on the rota-rod test. The LD50 value for HAE was found to be 4.8 g/kg. HAE and its fractions did not show neurotoxic effects in cultured PC12 cell line.

CONCLUSION

The results showed that P. abrotanoides significantly potentiated pentobarbital hypnosis without toxic effect. Probably, its effects are related to its non-polar constituents.

Evaluation of the effect of Pulicaria gnaphalodes and Perovskia abrotanoides essential oil extracts against Mycobacterium tuberculosis strains

Background:

Mycobacterium tuberculosis (MTB) is the causative agent of tuberculosis (TB), which remains one of the major public health problems in the world. The increasing incidence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) worldwide highlights the urgent need to search for alternative antimycobacterial agents. More and more people in developing countries utilize traditional medicine for their major primary health care needs. It has been determined that the medicinal plants Pulicaria gnaphalodes and Perovskia abrotanoides possess strong antibacterial effect.

Materials and Methods:

In this study, the antimycobacterial effects of P. gnaphalodes and P. abrotanoides essential oil on MTB were examined. Essential oil was prepared from P. gnaphalodes aerial parts and P. abrotanoides flower. The effects of six different concentrations (20 μg/ml, 40 μg/ml, 80 μg/ml, 160 μg/ml, 320 μg/ml, and 640 μg/ml) were examined against sensitive isolates of MTB and MTB H37Rv (ATCC 27294).

Results:

The results showed that P. gnaphalodes and P. abrotanoides essential oil extracts have strong inhibitory effects on MTB. This activity for P. gnaphalodes was observed from very low (4%) to good (70.9%) effect; meanwhile, this activity for P. abrotanoides was observed from very low (4%) to strong (86%) effect.

Conclusion:

The mean of inhibition percentage for P. gnaphalodes and P. abrotanoides in 640 μg/ml was 58.1% and 76.2%, respectively. So, P. abrotanoides plant is more effective against MTB than P. gnaphalodes. Identification of the effective fraction against MTB is a further step to be studied.

Ctotoxic and apoptogenic effects of Perovskia abrotanoides flower extract on MCF-7 and HeLa cell lines

OBJECTIVE

Perovskia abrotanoides Karel, belongs to the family Lamiaceae and grows wild alongside the mountainous roads inarid and cold climate of Northern Iran. The anti-tumor activity of P. abrotanoides root extract has been shown previously. This study was designed to examine in vitro anti-proliferative and pro-apoptotic effects of flower extract of P. abrotanoides on MCF-7 and Hela cell lines.

MATERIALS AND METHODS

Cells were cultured in DMEM medium with 10% fetal bovine serum, 100 units/ml penicillin and 100 µg/ml streptomycin and incubated with different concentrations of plant extracts. Cell viability was quantified by MTT assay. Apoptotic cells were determined using propidium iodide (PI) staining of DNA fragmentation by flow cytometry (sub-G1 peak).

RESULTS

P. abrotanoides extract inhibited the growth of malignant cells in a time and dose-dependent manner and 1000 µg/ml of extract following 48h of incubation was the most cytotoxic dose against Hela cell in comparison with other doses; however, in MCF-7 cells,1000 and 500 µg/ml PA induced toxicity at all time points but with different features.. Analysis of flowcytometry histogram of treated cells compared with control cells indicated that the cytotoxic effect is partly due toapoptosis induction.

CONCLUSION

Hydro-alcoholic extract of P. abrotanoides flowers inhibits the growth of MCF-7 and HeLa cell lines, partly via inducing apoptosis. Their inhibitory effect was increased in a time and dose-dependent manner, especially in MCF7 cells. However, further studies are needed to reveal the mechanisms of P. abrotanoides extract-induced cell death.

The Antimicrobial Activity of Essential Oil from Perovskia abrotanoides Karel and its Main Components

In Iranian folk medicine, Perovskia abrotanoides is used for treatment of leishmaniasis. These patients may develop secondary infections with opportunistic microorganisms. Therefore, the antimicrobial activity of essential oil from aerial part of P. abrotanoides and its main components was evaluated against different microorganisms. Disc diffusion and broth micro dilution assays were used for in vitro antimicrobial screening. The antibacterial activity of this oil and main components on viability of S. aureus was determined. The oil showed antimicrobial activity against Candida albicans and Gram positive bacteria especially Staphylococcus aureus with zone inhibitions and minimal inhibitory concentration values in the range of 7.6 to 29 mm and 2 to 8 μl/ml respectively, whereas the least susceptible were Aspergillus niger and Gram negative bacteria. In viability test, the results showed that the antimicrobial activity of 1,8-cineole was more than that of α-pinene and camphor but after 60 min this effect gradually decreased only for 1,8-cineole and ultimately the antibacterial activity of camphor was more than that of α-pinene. 1,8-cineole had weak antimicrobial activity against all of the tested microorganisms. Hence the use of P. abrotanoides oil could be useful in fighting secondary infections in leishmaniasis especially against S. aureus.