In vitro antitumor activity of the ethyl acetate extract of Potentilla chinensis in osteosarcoma cancer cells

Oxidative stress induced by Pollonein-LAAO, a new L-amino acid oxidase from Bothrops moojeni venom, prompts prostate tumor spheroid cell death and impairs the cellular invasion process in vitro

Cancer cells produce abnormal levels of reactive oxygen species (ROS) that contribute to promote their malignant phenotype. In this framework, we hypothesized that the change in ROS concentration above threshold could impair key events of prostate cancer cells (PC-3) progression. Our results demonstrated that Pollonein-LAAO, a new L-amino acid oxidase obtained from Bothrops moojeni venom, was cytotoxic to PC-3 cells in two-dimensional and in tumor spheroid assays. Pollonein-LAAO was able to increase the intracellular ROS generation that culminates in cell death from apoptosis by both intrinsic and extrinsic pathways due to the up-regulation of TP53, BAX, BAD, TNFRSF10B and CASP8. Additionally, Pollonein-LAAO reduced mitochondrial membrane potential and caused G0/G1 phase to delay, due to the up-regulation of CDKN1A and the down-regulation of the expression of CDK2 and E2F. Interestingly, Pollonein-LAAO inhibited critical steps of the cellular invasion process (migration, invasion and adhesion), due to the down-regulation of SNAI1, VIM, MMP2, ITGA2, ITGAV and ITGB3. Furthermore, the Pollonein-LAAO effects were associated with the intracellular ROS production, since the presence of catalase restored the invasiveness of PC-3 cells. In this sense, this study contributes to the potential use of Pollonein-LAAO as ROS-based agent to enhance the current understanding of cancer treatment strategies.

Cytotoxic, In Vitro Enzyme Inhibitory Potential and Phytochemical Profiling of Odontonema Strictum

Background

Odontonema strictum is an herbaceous plant, indigenous to Central America and Central Africa, and has been used traditionally by the local community against various ailments. The current piece of work was carried out to evaluate the cytotoxic potential of O. strictum by using brine shrimp lethality and the in vitro cytotoxicity/viability assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide [MTT]), as well as the in vitro enzyme inhibitory potential by using alpha-amylase, protein kinase enzymes and phytochemical analysis of the different extracts of aerial parts of O. strictum.

Materials and Method

Extracts of aerial parts of O. strictum were prepared through the successive extraction method using solvents with the order of polarity as n-hexane, dichloromethane, ethyl acetate, methanol and water. Cytotoxicity was assessed through brine shrimp lethality assay and in vitro cell viability assay (MTT), whereas enzyme inhibition potential was evaluated through Alpha-amylase and protein kinase assay. Phytochemical analysis was done by assessing the total phenolic and total flavonoid contents of both leaves and flowers.

Results

All the extracts exhibited various phytochemical and biological activities. Remarkable toxicity profiles against the brine shrimp lethality assay (LD50:11.5 µg/mL) were shown by the leaf extracts, whereas both leaves and flowers exhibited promising anti-proliferative activity, assessed by the MTT assay. Significant alpha-amylase and protein kinase inhibition potential were manifested by leave extracts with IC50:195.6 µg/mL and minimum inhibitory concentration (MIC): 16.3 µg/mL respectively. The phytochemical analysis of the plant showed that it was sufficiently rich in phenolic compounds with a total phenolic content and total flavonoid content (96.8 µg GAE/mg and 65.1 µg QE/mg, respectively).

Conclusion

It is plausible to believe that the cytotoxic and enzymatic activity of the aerial parts of O. strictum aerial parts might be, at least partly, to the presence of phenolic chemicals and could be a possible source of cytotoxic agent and an enzyme inhibitor.

Efficacy of Trevesia palmata (Roxb. ex Lindl.) Vis. Extract on MG 63 cell lines and arthritis-induced animal models

ETHNOPHARMACOLOGICAL RELEVANCE

Despite widespread use of herbal remedies for treating arthritis and osteosarcoma, many plants are still not pharmacologically evaluated for their efficacy. Contrary to many non-steroidal, immunosuppressants, antibiotics, and antineoplastic drugs that have adverse effects, phytotherapeutic compounds have promising benefits with fewer complications. In this study the unexplored Northeastern India indigenous plant Trevesia palmata (Roxb. ex Lindl.) Vis. used in traditional medicine to cure bone fractures is chosen for studying anti-proliferative and anti-rheumatic properties.

AIM OF THE STUDY

This study designed to explore the polyphenolic composition, antioxidant, anti-inflammatory and anti-arthritic potential of T. palmata leaf extracts. Further, the cellular activity was studied using MG 63 osteoblast cell lines and pharmacologically evaluated using Complete Freund's Adjuvant (CFA) induced arthritic rat model.

MATERIALS AND METHODS

In vitro free radical scavenging activity, anti-inflammatory and anti-arthritic activities of extracts were analyzed using standardized methods. The polyphenolic profiling and apoptosis inducing ability of T. palmata ethyl acetate (TPEA) extract on MG 63 osteoblast cell lines were analyzed. The in vivo pharmacological studies were carried out with low dose 250 mg/kg and high dose of 500 mg/kg of T. palmata. The biochemical and haematological parameters and in vivo antioxidant activity were evaluated for the control and treated groups. Radiological and histological study were done to understand the impact and penetration of inflammatory arthritis from tissues to joint bones.

RESULTS

TPEA showed highest free radical scavenging activity (DPPH - 4.72 IC₅₀, ABTS - 242.33 ± 6.81 mM TE/g extract), anti-inflammatory (40.04% inhibition of RBC lysis) and anti-arthritic activity (32.4% inhibition of protein denaturation) with the presence of gallic acid, catechin, caffeic acid, rutin, quercetin and naringenin. The TPEA extract inhibited cell proliferation of MG 63 osteoblast cells and induced apoptosis by arresting cell cycle at different phases. After acute toxicity studies the doses 250 mg/kg and 500 mg/kg were fixed and showed better results in CFA-induced arthritic animals. Thus, the extract phytoconstituents may have immense potential against chronic inflammation, joint ailments, bone cancer and arthritis which serves as a phytomedicine contrary to synthetic medications.

CONCLUSIONS

The potential treatment of polyphenolic compounds in the T. palmata extract on osteosarcoma and arthritis was demonstrated from this study. Thus, cellular inflammatory infiltrates are significantly reduced in bone and joint tissues as well.

Potentilloside A, a New Flavonol-bis-Glucuronide from the Leaves of Potentilla chinensis, Inhibits TNF-α-Induced ROS Generation and MMP-1 Secretion

The major contributor to skin aging is UV radiation, which activates pro-inflammatory cytokines including TNF-α. TNF-α is involved in the acceleration of skin aging via ROS generation and MMP-1 secretion. In our preliminary study, a 30% EtOH extract from the leaves of Potentilla chinensis (LPCE) significantly inhibited TNF-α-induced ROS generation in human dermal fibroblasts (HDFs). Therefore, the objective of this study is to identify the active components in LPCE. A new flavonol-bis-glucuronide (potentilloside A, 1) and 14 known compounds (2-15) were isolated from an LPCE by repeated chromatography. The chemical structure of the new compound 1 was determined by analyzing its spectroscopic data (NMR and HRMS) and by acidic hydrolysis. Nine flavonols (2-9 and 11) and two flavone glycosides (12 and 13) from P. chinensis were reported for the first time in this study. Next, we evaluated the effects of the isolates (1-15) on TNF-α-induced ROS generation in HDFs. As a result, all compounds significantly inhibited ROS generation. Furthermore, LPCE and potentilloside A (1) remarkably suppressed MMP-1 secretion in HDFs stimulated by TNF-α. The data suggested that LPCE and potentilloside A (1) are worthy of further experiments for their potential as anti-skin aging agents.

Vitexin isolated from Prosopis cineraria leaves induce apoptosis in K-562 leukemia cells via inhibition of the BCR-ABL-Ras-Raf pathway

OBJECTIVES

Leukemia is one of the severe cancer types all around the globe. Even though some chemotherapeutic drugs are available for treating leukemia, they have various side effects. As an alternative approach, herbal drugs are focused on current research to overcome leukemia. The present work was conducted to investigate the antileukemic mechanism of active phytochemical vitexin, which was isolated from ethno-medicine (Prosopis cineraria leaf) used by traditional healers of West Bengal, India.

METHODS

Antiproliferative mechanisms of selected phyto-compound against K-562 cells were evaluated using cellular uptake, morphological changes, DNA fragmentation, mitochondrial membrane potential and signaling pathways analysis.

KEY FINDINGS

Vitexin exhibited cytotoxicity by reducing mitochondrial membrane potential (32.40%) and causing DNA fragmentation (84.15%). The western blotting study indicated inhibition of cell survival proteins (BCR, ABL, H-RAS, N-RAS, K-RAS and RAF) and expression of apoptotic proteins (p38, BAX and caspase-9) in leukemia cells upon treatment with vitexin.

CONCLUSIONS

Based on the results, presently investigated phyto-compound vitexin could be considered for developing safe and natural drugs to treat leukemia after conducting suitable preclinical and clinical trials.

Recent phytochemical and pharmacological advances in the genus Potentilla L. sensu lato - An update covering the period from 2009 to 2020

ETHNOPHARMACOLOGICAL RELEVANCE

Potentilla plants are still common herbal medicines used in folk medicine. This review provides an update of research undertaken on Potentilla from 2009 until 2020.

AIM OF THE STUDY

This comprehensive review considers biological updates, recent advances in phytochemical and pharmacological research, and toxicological reports on Potentilla sensu lato based on available data since 2009.

METHODS

A literature search was conducted using available databases including ScienceDirect, PubMed, Scopus, Web of Science, China National Knowledge Infrastructure and Google Scholar.

RESULTS

Until now, more than 210 new and known compounds, including flavonoids, tannins, triterpenes and phenolic compounds, have been confirmed and elucidated for numerous Potentilla species, i.e., in the underground and aerial parts of this genus. Modern pharmacology studies have revealed that those structures are responsible for a broad spectrum of pharmacological activities, such as anti-neoplastic, antihyperglycemic, anti-inflammatory, antioxidant, hepatoprotective, neuroprotective, antibacterial and anti-yeast effects.

CONCLUSIONS

However, in vitro studies must be re-considered due to the discovery of urolithins and their origins, including microbiota, which can lead to different results when applying Potentilla species and their extracts to in vivo conditions. Thus, future research should focus more on in vivo and particularly clinical studies to confirm the validity and safety of traditional uses. Particularly, the use of Potentilla alba extracts in the treatment of thyroid gland disorders should be further explored to confirm the underlying mechanism of their action, efficacy and safety. In addition, more clinical studies should focus on Potentilla erecta rhizome extracts for application as herbal remedies against dysentery, diarrhoea and inflammation of the skin.

Potentilla alba Extracts Affect the Viability and Proliferation of Non-Cancerous and Cancerous Colon Human Epithelial Cells

The aim of this study was to determine the anti-tumor activity of extracts isolated from Potentilla alba L. on human colon cancer cells of the HT-29 line and on non-cancer colon epithelial cells of the CCD 841 CoTr line. The research methods we used to determine the cytotoxic and proliferative properties were 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and neutral red (NR) assays, the ability to produce nitric oxide, the Griess method, and the biochemical properties like 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods indicating reduction activity of tested samples. In order to obtain a phytochemical profile of the different extracts an analytical method based on liquid chromatography-photodiode array detection-electrospray ionization ion-trap time-of-flight mass spectrometry (LC-PDA-ESI-MS/TOF) was applied. Finally, the effects of the extracts on the morphology and cell counts were assessed by May–Grünwald–Giemsa staining. After a comprehensive analysis of all the experiments, the extracts were found to demonstrate cytotoxic properties, they stimulated the division of non-cancer cells, and they were able to scavenge free radicals. In the NR method, the cell viability dropped to approximately 80% compared to the control. In the MTT assay, tumor cell proliferation decreased to 9.5% compared to the control. Therefore, we concluded that this plant has medical potential.

Curcumin Analog DK1 Induces Apoptosis in Human Osteosarcoma Cells In Vitro through Mitochondria-Dependent Signaling Pathway

Osteosarcoma is one of the primary malignant bone tumors that confer low survival rates for patients even with intensive regime treatments. Therefore, discovery of novel anti-osteosarcoma drugs derived from natural products that are not harmful to the normal cells remains crucial. Curcumin is one of the natural substances that have been extensively studied due to its anti-cancer properties and is pharmacologically safe considering its ubiquitous consumption for centuries. However, curcumin suffers from a poor circulating bioavailability, which has led to the development of a chemically synthesized curcuminoid analog, namely (Z)-3-hydroxy-1-(2-hydroxyphenyl)-3-phenylprop-2-en-1-one (DK1). In this study, the cytotoxic effects of the curcumin analog DK1 was investigated in both U-2OS and MG-63 osteosarcoma cell lines using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and cell death was microscopically examined via acridine orange/propidium iodide (AO/PI) double staining. Flow cytometer analysis including Annexin V/Fluorescein isothiocyanate (FITC), cell cycle analysis and JC-1 were adapted to determine the mode of cell death. Subsequently in order to determine the mechanism of cell death, quantitative polymerase chain reaction (qPCR) and proteome profiling was carried out to measure the expression of several apoptotic-related genes and proteins. Results indicated that DK1 induced U-2 OS and MG-63 morphological changes and substantially reduced cell numbers through induction of apoptosis. Several apoptotic genes and proteins were steadily expressed after treatment with DK1; including caspase 3, caspase 9, and BAX, which indicated that apoptosis occurred through a mitochondria-dependent signaling pathway. In conclusion, DK1 could be considered as a potential candidate for an anti-osteosarcoma drug in the near future, contingent upon its ability to induce apoptosis in osteosarcoma cell lines.