Inhibitory activity of traditional plants against Mycobacterium smegmatis and their action on Filamenting temperature sensitive mutant Z (FtsZ)-A cell division protein

An adamantyl-caffeoyl-anilide exhibits broad-spectrum antibacterial activity by inhibiting FtsZ assembly and Z-ring formation

Several harmful bacteria have evolved resistance to conventional antibiotics due to their extensive usage. FtsZ, a principal bacterial cell division protein, is considered as an important drug target to combat resistance. We identified a caffeoyl anilide derivative, (E)-N-(4-(3-(3,4-dihydroxyphenyl)acryloyl)phenyl)-1-adamantylamide (compound 11) as a new antimicrobial agent targeting FtsZ. Compound 11 caused cell elongation in Mycobacterium smegmatis, Bacillus subtilis, and Escherichia coli cells, indicating that it inhibits cell partitioning. Compound 11 inhibited the assembly of Mycobacterium smegmatis FtsZ (MsFtsZ), forming short and thin filaments in vitro. Interestingly, the compound increased the rate of GTP hydrolysis of MsFtsZ. Compound 11 also impeded the assembly of Mycobacterium tuberculosis FtsZ. Fluorescence and absorption spectroscopic analysis suggested that compound 11 binds to MsFtsZ and produces conformational changes in FtsZ. The docking analysis indicated that the compound binds at the interdomain cleft of MsFtsZ. Further, it caused delocalization of the Z-ring in Mycobacterium smegmatis and Bacillus subtilis without affecting DNA segregation. Notably, compound 11 did not inhibit tubulin polymerization, the eukaryotic homolog of FtsZ, suggesting its specificity on bacteria. The evidence indicated that compound 11 exerts its antibacterial effect by impeding FtsZ assembly and has the potential to be developed as a broad-spectrum antimicrobial agent.

Mycobacterial FtsZ and inhibitors: a promising target for the anti-tubercular drug development

The emergence of multidrug-resistant tuberculosis (MDR-TB) strains has rendered many anti-TB drugs ineffective. Consequently, there is an urgent need to identify new drug targets against Mycobacterium tuberculosis (Mtb). Filament Forming Temperature Sensitive Gene Z (FtsZ), a member of the cytoskeletal protein family, plays a vital role in cell division by forming a cytokinetic ring at the cell's center and coordinating the division machinery. When FtsZ is depleted, cells are unable to divide and instead elongate into filamentous structures that eventually undergo lysis. Since the inactivation of FtsZ or alterations in its assembly impede the formation of the Z-ring and septum, FtsZ shows promise as a target for the development of anti-mycobacterial drugs. This review not only discusses the potential role of FtsZ as a promising pharmacological target for anti-tuberculosis therapies but also explores the structural and functional aspects of the mycobacterial protein FtsZ in cell division. Additionally, it reviews various inhibitors of Mtb FtsZ. By understanding the importance of FtsZ in cell division, researchers can explore strategies to disrupt its function, impeding the growth and proliferation of Mtb. Furthermore, the investigation of different inhibitors that target Mtb FtsZ expands the potential for developing effective treatments against tuberculosis.

Deciphering the emerging role of phytocompounds: Implications in the management of drug-resistant tuberculosis and ATDs-induced hepatic damage

Tuberculosis is a disease of poverty, discrimination, and socioeconomic burden. Epidemiological studies suggest that the mortality and incidence of tuberculosis are unacceptably higher worldwide. Genomic mutations in embCAB, embR, katG, inhA, ahpC, rpoB, pncA, rrs, rpsL, gyrA, gyrB, and ethR contribute to drug resistance reducing the susceptibility of Mycobacterium tuberculosis to many antibiotics. Additionally, treating tuberculosis with antibiotics also poses a serious risk of hepatotoxicity in the patient's body. Emerging data on drug-induced liver injury showed that anti-tuberculosis drugs remarkably altered levels of hepatotoxicity biomarkers. The review is an attempt to explore the anti-mycobacterial potential of selected, commonly available, and well-known phytocompounds and extracts of medicinal plants against strains of Mycobacterium tuberculosis. Many studies have demonstrated that phytocompounds such as flavonoids, alkaloids, terpenoids, and phenolic compounds have antibacterial action against Mycobacterium species, inhibiting the bacteria's growth and replication, and sometimes, causing cell death. Phytocompounds act by disrupting bacterial cell walls and membranes, reducing enzyme activity, and interfering with essential metabolic processes. The combination of these processes reduces the overall survivability of the bacteria. Moreover, several phytochemicals have synergistic effects with antibiotics routinely used to treat TB, improving their efficacy and decreasing the risk of resistance development. Interestingly, phytocompounds have been presented to reduce isoniazid- and ethambutol-induced hepatotoxicity by reversing serum levels of AST, ALP, ALT, bilirubin, MDA, urea, creatinine, and albumin to their normal range, leading to attenuation of inflammation and hepatic necrosis. As a result, phytochemicals represent a promising field of research for the development of new TB medicines.

Anti-Alzheimer Potential of a New (+)-Pinitol Glycoside Isolated from Tamarindus indica Pulp: In Vivo and In Silico Evaluations

Tamarindus indica Linn (tamarind, F. Leguminosae) is one of the most widely consumed edible fruits in the world. Phytochemical investigation of tamarind pulp n-butanol fraction yielded one new (+)-pinitol glycoside compound 1 (25% w/w), and 1D, 2D NMR, and HRESIMS investigation were used to confirm the new compound's structure. (+)-Pinitol glycoside showed anti-Alzheimer potential that was confirmed in prophylactic and treatment groups by decreasing time for the T-maze test; decreased TAO, brain and serum AChE, MDA, tau protein levels, and β amyloid peptide protein levels; and increasing GPX, SOD levels, and in vivo regression of the neurodegenerative features of Alzheimer's dementia in an aluminum-intoxicated rat model. The reported molecular targets for human Alzheimer's disease were then used in a network pharmacology investigation to examine their complex interactions and identify the key targets in the disease pathogenesis. An in silico-based analysis (molecular docking, binding free energy calculation (ΔG_Binding), and molecular dynamics simulation) was performed to identify the potential targets for compound 1. The findings of this study may lead to the development of dietary supplements for the treatment of Alzheimer's disease.

D-Pinitol-Active Natural Product from Carob with Notable Insulin Regulation

Carob is one of the major food trees for peoples of the Mediterranean basin, but it has also been traditionally used for medicinal purposes. Carob contains many nutrients and active natural products, and D-Pinitol is clearly one of the most important of these. D-Pinitol has been reported in dozens of scientific publications and its very diverse medicinal properties are still being studied. Presently, more than thirty medicinal activities of D-Pinitol have been reported. Among these, many publications have reported the strong activities of D-Pinitol as a natural antidiabetic and insulin regulator, but also as an active anti-Alzheimer, anticancer, antioxidant, and anti-inflammatory, and is also immune- and hepato-protective. In this review, we will present a brief introduction of the nutritional and medicinal importance of Carob, both traditionally and as found by modern research. In the introduction, we will present Carob’s major active natural products. The structures of inositols will be presented with a brief literature summary of their medicinal activities, with special attention to those inositols in Carob, as well as D-Pinitol’s chemical structure and its medicinal and other properties. D-Pinitol antidiabetic and insulin regulation activities will be extensively presented, including its proposed mechanism of action. Finally, a discussion followed by the conclusions and future vision will summarize this article.

A method for the enrichment, isolation and validation of Mycobacterium smegmatis population surviving in the presence of bactericidal concentrations of rifampicin and moxifloxacin

The bacterial populations surviving in the presence of antibiotics contain cells that have gained genetic resistance, phenotypic resistance and tolerance to antibiotics. Isolation of live bacterial population, surviving against antibiotics, from the milieu of high proportions of dead/damaged cells will facilitate the study of the cellular/molecular processes used by them for survival. Here we present a Percoll gradient centrifugation based method for the isolation of enriched population of Mycobacterium smegmatis surviving in the presence of bactericidal concentrations of rifampicin and moxifloxacin. From the time of harvest, throughout the enrichment and isolation processes, and up to the lysis of the cells for total RNA preparation, we maintained the cells in the presence of the antibiotic to avoid changes in their metabolic status. The total RNA extracted from the enriched population of live antibiotic-surviving population showed structural integrity and purity. We analysed the transcriptome profile of the antibiotic-surviving population and compared it with the orthologue genes of Mycobacterium tuberculosis that conferred antibiotic tolerance on tubercle bacilli isolated from the tuberculosis patients under treatment with four antitubercular antibiotics. Statistically significant comparability between the gene expression profiles of the antibiotic tolerance associated genes of M. smegmatis and M. tuberculosis validated the reliability/utility of the method.

Polyphenol-rich Indian ginger cultivars ameliorate GLUT4 activity in C2C12 cells, inhibit diabetes-related enzymes and LPS-induced inflammation: An in vitro study

Diabetes is a chronic metabolic disorder that results in distorted insulin signaling and microvascular complications. Current antidiabetic drugs possess harmful long term side effects, necessitating the need for alternate or compliment therapy with lesser issues. Medicinal plants such as ginger have been reported to possess several beneficial activities including antidiabetic activity. The antidiabetic efficacy of microwave-assisted polyphenolic extracts of Indian ginger cultivars from Odisha (MPO) and Tamil Nadu (MPT) is reported here. MPT and MPO showed insulin stimulated glucose uptake of 1.74 ± 0.25 and 1.47 ± 0.15 fold at 6.25 µg/ml of concentrations in C2C12 cells respectively when compared to control. MPT possessed α-amylase, α-glucosidase inhibitory and anti-glycation properties. It also showed DPPH radical scavenging activity (7.69 ± 0.001%), inhibited LPS-induced nitric oxide production (1.06 ± 0.004 fold) than the latter and increased the GLUT4 protein expression by 1.4 fold. Major active compounds such as shogaol and gingerol derivatives, curcumene, zingiberone were identified through GC-ESI/MS analysis and D-pinitol (cyclitol) was identified through HPLC analysis in this variety. This is the first paper to report the presence of an antidiabetic compound, D-pinitol, in the ginger variety. Polyphenol rich, biologically potent ginger extracts can be a good food and nutraceutical supplement to address diabetes and related complications. PRACTICAL APPLICATIONS: Ginger is a native spice of South Asian Countries including India. Ginger extracts possess several medicinal properties such as anti-inflammatory, antidiabetic and antioxidant activities. It is used to treat nausea, vomiting and commonly used as a food flavouring agent and dietary food supplement. Our study shows the antidiabetic, anti-glycation and antioxidant efficacy of polyphenol rich Indian ginger cultivars grown in different geographical regions. Variations in the biological activities between the MPT and MPO ginger variety was observed. Different environmental conditions and their corresponding metabolite accumulation can be correlated with the better activity shown by MPT variety. It showed an increased GLUT4 expression even at a lower dose of 6.25 µg/ml. Ginger cultivar, especially MPT variety can be used as an adjuvant therapy for treating diabetes. Therefore, our study indicates that polyphenols rich ginger cultivar has major application in functional food product development.

Preparation of Curdlan sulphate - Chitosan nanoparticles as a drug carrier to target Mycobacterium smegmatis infected macrophages

In this study, curdlan sulphate - chitosan nanoparticles were prepared through polyelectrolyte complexing at a mass ratio of 2:1 respectively. The curdlan was produced by fermentation with Agrobacterium sp. ATCC 31750, which was then sulphated to form the polyanionic polymer. A first-line tuberculosis drug, Rifampicin and a phytochemical, DdPinitol, were encapsulated into Curdlan Sulphate (CS) - Chitosan Nanoparticles (C) (CSC NPs) of size 205.41 ± 7.24 nm. The drug release kinetics followed a Weibull model with initial burst release (48 % Rifampicin and 27 % d-Pinitol within 6 h), followed by a sustained release. The prepared CSC: d-PIN + RIF NPs was cytocompatible and entered the M.smegmatis infected macrophages through multiple endocytic pathways including clathrin, caveolae and macropinocytosis. They showed superior bactericidal activity (2.4-2.7 fold) within 4 h when compared to free drug Rifampicin (1.6 fold). The drug encapsulated CSC: RIF suppressed the pro-inflammatory gene (TNF-α by 3.66 ± 0.19 fold) and CSC: d-PIN + RIF increased expression of the anti-inflammatory gene (IL-10 by 13.09 ± 0.47 fold). Expression of TGF- β1 gene also increased when treated with CSC: d-PIN + RIF (13.00 ± 0.19 fold) which provided the immunomodulatory activity of the encapsulated CSC NPs. Thus, curdlan sulphate - chitosan polyelectrolyte complex can be a potential nanocarrier matrix for intracellular delivery of multiple drugs.