Synthesis of friedelan triterpenoid analogs with DNA topoisomerase IIα inhibitory activity and their molecular docking studies

Plant In Vitro Culture Factories for Pentacyclic Triterpenoid Production

Pentacyclic triterpenoids are a diverse subclass of naturally occurring terpenes with various biological activities and applications. These compounds are broadly distributed in natural plant resources, but their low abundance and the slow growth cycle of plants pose challenges to their extraction and production. The biosynthesis of pentacyclic triterpenoids occurs through two main pathways, the mevalonic acid (MVA) pathway and the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway, which involve several enzymes and modifications. Plant in vitro cultures, including elicited and hairy root cultures, have emerged as an effective and sustainable system for pentacyclic triterpenoid production, circumventing the limitations associated with natural plant resources. Bioreactor systems and controlling key parameters, such as media composition, temperature, light quality, and elicitor treatments, have been optimized to enhance the production and characterization of specific pentacyclic triterpenoids. These systems offer a promising bioprocessing tool for producing pentacyclic triterpenoids characterized by a low carbon footprint and a sustainable source of these compounds for various industrial applications.

Studying the interaction of scopolamine with calf-thymus DNA: An in-vitro and in-silico approach and genotoxicity

Scopolamine is used to treat various CNS disorder like urinary incontinence, motion sickness, spasmic movements. Despite its pharmaceutical properties, its interaction with DNA is not yet reported. In this article, the interaction between scopolamine and ct-DNA is reported using a combination of biophysical techniques. UV-visible and steady-state fluorescence spectroscopy were used to study interaction and complex formation. Competitive displacement assays and potassium iodide quenching confirmed the mode of binding between scopolamine and DNA. Structural changes induced in the ct-DNA in the presence of scopolamine were evaluated by CD spectroscopy. The plasmid nicking and NBT assay confirmed the genotoxic effect of scopolamine. In-silico study by molecular docking and molecular dynamics simulation revealed the mode of interaction, major stabilizing forces as well as the nucleotide sequences to which the scopolamine binds.

Interaction of thiamethoxam with DNA: Hazardous effect on biochemical and biological parameters of the exposed organism

In the present scenario, insecticides/pesticides are used intensively to control the various insect pests. Indiscriminate use of these insecticides/pesticides affects the structure and function of the ecosystem. In this context, a thorough toxicological study of each insecticide/pesticide is a must to understand the hazardous effect of these chemicals on the target and non-target organisms. The present study was aimed to understand the hazardous effect of thiamethoxam against the Spodoptera litura. Different concentrations (20-80 μg/mL) of thiamethoxam were prepared, and fourth instar larvae of S. litura were allowed to feed for 12-72 h. We first examined the interaction of thiamethoxam with DNA. Next, treated and non-treated larvae were assessed for different biological parameters such as mortality, emergence, fecundity, fertility, longevities, and biochemical parameters. Our result showed that thiamethoxam directly interacts with the DNA and significantly influenced the different biological and biochemical parameters of exposed the organisms. We observed a significant change in stress enzymes such as SOD, CAT, and GST. A similar observation was also made with the oxidative marker for lipid damage, MDA and DNA damage, 8-OHdG, respectively. In conclusion, our results suggest that improper use of synthetic chemical insecticides influenced both biological and biochemical parameters through oxidative stress and probably damage the genetic material.

Design, Synthesis, and Anticancer Evaluation of Novel Indole Derivatives of Ursolic Acid as Potential Topoisomerase II Inhibitors

In this study, a series of new indole derivatives of ursolic acid bearing different N-(aminoalkyl)carboxamide side chains were designed, synthesized, and evaluated for their in vitro cytotoxic activities against two human hepatocarcinoma cell lines (SMMC-7721 and HepG2) and normal hepatocyte cell line (LO2) via MTT assay. Among them, compound 5f exhibited the most potent activity against SMMC-7721 and HepG2 cells with IC50 values of 0.56 ± 0.08 μM and 0.91 ± 0.13 μM, respectively, and substantially lower cytotoxicity to LO2 cells. A follow-up enzyme inhibition assay and molecular docking study indicated that compound 5f can significantly inhibit the activity of Topoisomerase IIα. Further mechanistic studies performed in SMMC-7721 cells revealed that compound 5f can elevate the intracellular ROS levels, decrease mitochondrial membrane potential, and finally lead to the apoptosis of SMMC-7721 cells. Collectively, compound 5f is a promising Topoisomerase II (Topo II) inhibitor, which exhibited the potential as a lead compound for the discovery of novel anticancer agents.

Elucidating the interaction of aminophylline with calf thymus DNA using multispectroscopic and molecular docking approach

Aminophylline (Am) is a methylxanthine compound clinically applied for chronic lung diseases like asthma, bronchitis or emphysema. Chemically, it comprises theophylline and ethylenediamine in a ratio 2:1. For the widening of the therapeutic window of any class of drug or for the designing of the newer therapeutic compound, an insight into the binding mechanics of available drugs with DNA is quite imperative. In view of that, here in this study we have investigated binding mechanics of aminophylline molecule with calf thymus DNA (Ct-DNA) using various spectroscopic techniques as well as molecular docking approach. Spectral analysis employing UV-visible and fluorescence approach confirmed the formation of aminophylline-Ct-DNA complex. The binding constant was calculated as 3.5 × 10⁴ M^-1 with 0.90 as the value of binding site suggestive of minor groove binding mode of aminophylline. The groove binding mode was further confirmed through spectrofluorimetric experiments like competitive displacement assay employing ethidium bromide, hoechst and rhodamine 6 G dyes as well as iodide quenching studies. The circular dichroic spectral evaluation and molecular docking study finally validated the minor groove binding mode of aminophylline with binding energy calculated as -4.5 Kcal/mol.

Role of Pentacyclic Triterpenoids in Chemoprevention and Anticancer Treatment: An Overview on Targets and Underling Mechanisms

The incidences of cancer are continuously increasing worldwide, affecting life of millions of people. Several factors associated with the internal and external environment are responsible for this deadly disease. The key internal determinants like abnormal hormonal regulation, genetic mutations and external determinants such as lifestyle and occupational factors enhances onset of cancer. From the ancient time, plants were remained as the most trusted source of medicine for the treatment of diverse disease conditions. Extensive studies have been performed for the discovery of effective anticancer agent from the plant and still it is going on. Pentacyclic triterpenoids are biologically active phytochemicals having a different range of activities such as anti-inflammatory, hepatoprotective, anti-hypertensive, antiulcerogenic and anti-tumor. These compounds generally contain ursane, oleanane, lupane and friedelane as a chief skeleton of pentacyclic triterpenoids which are generally present in higher plants. Isoprene unit, phytochemical, with good antitumor/anticancer activity is required for the biosynthesis of pentacyclic triterpenoids. Mechanisms such as cytotoxicity, DNA polymerase inhibition, regulation of apoptosis, change in signal transductions, interfere with angiogenesis and dedifferentiation, antiproliferative activity and metastasis inhibition are might be responsible for their anticancer effect. Present review spotlights diverse targets, mechanisms and pathways of pentacyclic triterpenoids responsible for anticancer effect.

Maytenus macrocarpa (Ruiz & Pav.) Briq.: Phytochemistry and Pharmacological Activity

Maytenus macrocarpa (Celastraceae) is a tree native to Amazonia. Its roots, leaves, bark, and combinations of these are used in traditional medicine mainly to treat rheumatism and, to a lesser extent, to heal wounds and to combat bronchitis and diarrhea. To date, mainly triterpenes and dihydro-β-agarofuran sesquiterpenes were isolated from M. macrocarpa. Extracts and selected pure compounds isolated from the leaves, roots, and stem bark showed antibacterial, antiviral, antiparasitic, anti-inflammatory, and cytotoxic activities in vitro. The aim of this review is to summarize the available ethnobotanical, phytochemical, and pharmacological information about this traditional Amazonian medicinal tree, as well as to attract the attention of phytochemists and pharmacognosists to this potentially interesting source of ethnopharmaceuticals.

Friedelane triterpenoids: transformations toward A-ring modifications including 2-homoderivatives

Common reaction strategies were employed on suitable substrates to achieve a series of C2,C3-; C3,C4- and C2,C3,C4-functionalized (including 2-homo-) friedelane triterpenoids with just one to four efficient steps.

Binding affinity of pyrano[3, 2-f]quinoline and DNA: spectroscopic and docking approach

The interaction between pyrano[3, 2-f]quinoline (PQ) and calf thymus DNA (CTDNA) using spectroscopic and molecular modeling approach has been presented here. Apparent association constant (1.05×10⁵ L/mol) calculated from UV-vis specta, indicates a moderate complex formation between CTDNA and PQ. The quenching phenomena as obtained from emission spectra of ethidium bromide (EB)-CTDNA by PQ was found to be a dynamic one and the binding constants found to be 8.64, 9.25, 11.17, 12.03 × 10⁴ L/mol at 293, 300, 308, and 315 K. Thermodynamic parameter enthalpy change (ΔH) and entropy change (ΔS), indicates weak force like van der Walls force and hydrogen bonds having the key role in this binding process. The results of circular dichroism (CD) demonstrate that PQ has not induced characteristic changed in CTDNA. Results achieved from UV absorption and fluorescence spectroscopy indicating the binding mode of PQ with DNA seems to be a nonintercalative binding. The theoretical results as originating from molecular modeling showed that PQ possibly will bind into the hydrophobic region of DNA having docking binding energy = -10.03 kcal/mol and the obtained results are in consonance with the inferences obtained from experimental data. This result is important for the better understanding of pharmaceutical aspects of binding affinity of PQ and CTDNA.

Anti-diabetic Effect of FriedelanTriterpenoids in Streptozotocin Induced Diabetic Rat

We herein report the anti-diabetic effect of the natural friedelan tritepenoid, 4-oxa-3, 4-secofriedelan (cerin), isolated from cork tissue of Quercus suber L. and its oxygenated derivative, 4-oxa-3, 4-secofriedelan-3-oic acid (cerinox) in streptozotocin (STZ)-induced diabetic rat. Male Sprague Dawley rats were randomized into four groups: non-diabetic control (Group I), STZ-induced diabetic rats (Group II), STZ-induced diabetic rats treated with cerin (Group III), and STZ-induced diabetic rats treated with cerinox (Group IV). Administration of cerin (3mg/kg) and cerinox (3mg/kg) orally to STZ-diabetic rats for three weeks improved the body weight, reduced serum glucose level and activities of alkaline phosphatase, acid phosphatase, glutamate-oxaloacetate transaminase and glutamate-pyruvate transaminase, and restored liver antioxidant status.

Synthesis and in vitro Screening of 29, 30-Dibromo-28-oxoallobetulin against Parasitic Protozoans, Leishmania donovani and Leishmania Major

A simple synthesis and in vitro antileishmanial activity of 29,30-dibromo-28-oxoallobetulin against the parasitic protozoans, Leishmania donovani and Leishmania major is described. The structure of the compound is established on the basis of spectral data (IR, NMR, MS). Both the antiproliferative effect and the cell cycle progression were studied.