Prevention of liver carcinogenesis by amarogentin through modulation of G1/S cell cycle check point and induction of apoptosis

Swertia chirayita: A comprehensive review on traditional uses, phytochemistry, quality assessment and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Swertia chirayita (Roxb.) H. Karst. is a traditionally used, well-recognized medicinal plant of the family Gentianaceae with significant therapeutic potential. It has been traditionally used to cure various ailments such as fever, vomiting, jaundice, digestive disorders, heart diseases, diabetes, malaria, scorpion bite, and skin diseases.

AIM OF REVIEW

The present review emphasized the traditional uses, phytochemistry, pharmacology, toxicology, chemical profiling, and structural identification of isolated compounds by analytical and spectroscopic techniques. This review demonstrates the possibility of advanced ethnopharmacological research.

MATERIALS AND METHODS

The literature on S. chirayita was obtained from bibliographic databases like Web of Science, PubMed, Science-Direct, American Chemical Society (ACS), Google Scholar, and SciFinder. The compiled review is covered up until March 2022.

RESULTS

Approximately, 123 specialized metabolites including xanthones, seco-iridoids, terpenoids, alkaloids, and flavonoids have been isolated and characterized from S. chirayita. The extract and isolated compounds exhibited a wide spectrum of pharmacological effects such as anti-inflammatory, antioxidant, antitumor, hepatoprotective, antiviral, antimalarial, and antibacterial offering scientific evidence for traditional claims of this medicinal plant. In addition, various analytical methods using HPTLC, UPLC, HPLC, LC-MS, and GC-MS have also been documented to determine the phytochemicals of S. chirayita.

CONCLUSION

The current article provides information on traditional usage, phytochemistry, chemical profiling, structure elucidation, pharmacological efficacy, toxicity, and future prospects of S. chirayita. This plant has long been traditionally used in a variety of ways by indigenous people. Numerous phytoconstituents and several pharmacological activities have been reported in S. chirayita. However, there are still some scientific gaps such as identification of bioactive compounds, structure-activity relationship and mechanistic action of isolated bioactive compounds, development of effective analytical methods for comprehensive quality control, and safety profiles that need to be addressed.

Impact of Amarogentin on Gastric Carcinoma Cell Multiplication, Apoptosis and Migration via circKIF4A/miR-152-3p

Objective

The active ingredients extracted from natural plants have anti-GC actions and can slow down gastric carcinoma (GC) progression. To investigate the impact of Amarogentin (AG) on GC cell multiplication, apoptosis and migration and the possible mechanisms.

Methods

qRT-PCR quantification of circKIF4A and miR-152-3p in GC tissues and normal counterparts as well as HGC-27 (human GC cell strain) and GES-1 (human gastric mucosal epithelial cell strain) was performed. HGC-27 cells were intervened by AG of various concentrations. si-NC, si-circKIF4A were further transfected into HGC-27 cells. Besides, pcDNA and pcDNA-circKIF4A were transfected into HGC-27 cells, after which 60 mmol/L AG was added for intervention. Cell multiplication, clone formation, as well as apoptosis and migration measurements were made by MTT, plate clone formation, flow cytometry and Transwell assays, respectively; Double luciferase reporter assay was performed for targeting relationship identification between circKIF4A and miR-152-3p; Western blots were carried out to measure Bax and Bcl-2 protein levels.

Results

circKIF4A increased (P <0.05) and miR-152-3p decreased (P <0.05) in GC tissues and cell strains. Concentration-dependently, AG intervention contributed to enhanced cell multiplication inhibitory rate, apoptosis rate, miR-152-3p expression and Bax protein level (P <0.05), together with declined number of cell clones formed, migrating cells, circKIF4A expression and Bcl-2 protein level (P <0.05). After transfection of si-circKIF4A, cell multiplication inhibition rate, apoptosis rate and Bax protein level enhanced (P <0.05), while cell clones formed and migrating cells as well as Bcl-2 protein level reduced (P <0.05). miR-152-3p can be controlled by circKIF4A; pcDNA-circKIF4A transfection antagonized AG's effects on HGC-27 cell multiplication, clone formation, apoptosis and migration.

Conclusion

AG can decrease GC multiplication, clone formation and migration and induce apoptosis via modulating circKIF4A/miR-152-3p expression.

Synergistic anti-cancer action of salicylic acid and cisplatin on HeLa cells elucidated by network pharmacology and in vitro analysis

AIM

To investigate the anti-cancer potential of salicylic acid and cisplatin combination in HeLa cells and the underlying mechanism.

MAIN METHODS

Drugs and disease targets were extracted from DrugBank, BATMAN-TCM, STITCH, PharmMapper and Comparative Toxigenomics Database. Cytoscape 3.8.2 was used to merge the protein-protein interaction networks and select core targets. GO and KEGG analysis was done using Metascape and WebGestalt. Effect of salicylic acid and cisplatin alone and in combination on cells viability was studied by MTT assay. The type of interaction between salicylic acid and cisplatin was determined by CompuSyn. Apoptosis was evaluated by molecular docking, Rhodamine-123, DAPI, AO/EtBr staining, flow cytometry, qRT-PCR and western blotting. Metastasis was studied using scratch assay and western blotting. UHRF1 transient silencing was performed by siRNA.

KEY FINDINGS

Out of 420, 1863 and 1362 respective targets of salicylic acid, cisplatin and cervical cancer, 18 core proteins were enriched in apoptosis and cell migration related pathways. IC50 value of cisplatin was reduced by 14 fold in combination with salicylic acid at IC20 (4 μM). There was loss of mitochondrial membrane potential and downregulation of UHRF1, pAkt, full length PARP and pro-caspase 3 expression. Transient silencing of UHRF1 also induced mitochondrial depolarization and apoptosis. The combination also exhibited anti-metastasis effect as it suppressed migration, upregulated PAX1 and downregulated MMP-2.

SIGNIFICANCE

Reduction in cisplatin concentration, enhanced anti-cancer effects and UHRF1 downregulation due to synergistic interaction between salicylic acid and cisplatin underscores the therapeutic importance of the combination to overcome chemo-resistance and side effects of cisplatin.

Eugenol emerges as an elixir by targeting β-catenin, the central cancer stem cell regulator in lung carcinogenesis: an in vivo and in vitro rationale

According to population-based studies, lung cancer has become one of the leading causes of death globally in males and is also rising in females at an alarming rate. The aim of this study was to exploit the inherent properties of eugenol to restrict the growth of cancer cells in a tobacco-related human carcinogen NDEA-induced lung carcinogenesis model in vivo as a chemopreventive agent. More precisely, by utilizing its abundance in nature, eugenol (a component of clove) was utilized to establish the molecular mechanism of chemoprevention in the NDEA-induced mouse lung carcinogenesis model in a substantial cost-effective manner and was validated in the A549 human lung cancer cell line. Our study especially targeted the tiny, drug-resistant, and most virulent subpopulation of cancer cells called CSCs by targeting their regulator molecule β-catenin. The non-toxic dosage of eugenol was shown to enhance apoptosis, simultaneously suppressing cell proliferation in the lung tissue of carcinogen-treated mice without affecting the normal mice. Combining cellular apoptosis and proliferation, eugenol showed an exceptional chemopreventive potential in this lung carcinogenesis model. Importantly, eugenol strongly restricted the lung carcinoma in the mild dysplastic stage as a chemopreventive agent. The molecular analysis remarkably depicted the restriction of β-catenin nuclear transportation. The minimized total β-catenin pool and induced N-terminal Ser37 phosphorylation form after eugenol treatment resulted in its cytoplasmic degradation. Consequently, CSC markers such as CD44, Oct4, EpCAM, and Notcht1, whose expression is dependent on β-catenin decreased significantly, as proven by IHC, ICC, and WB analysis both in vivo and in vitro. The in vitro secondary sphere formation assay also proved the remarkably repressed CSC population, and hence the virulence. In another way, eugenol was proven to significantly enhance the degradation of β-catenin when treated with the CK1α inhibitor D4476 in vitro by Western blot. CK1α in the Wnt/β-catenin pathway plays a crucial role for tagging with the N-terminal Ser45 phosphorylation of β-catenin, which ultimately opens a position for the decisive phosphorylation by GSK3β at the Ser37 residue to take place. Thus, the conclusive extermination of CSCs achieved that was associated with recurrence due to treatment failure. That can help to achieve a longer and better quality of life in a natural, economical way.

Revisiting nature: a review of iridoids as a potential antileishmanial class

Leishmaniasis still stands as one of the most prevalent neglected tropical diseases in the least developed and emerging countries. The recommended therapeutic arsenal to treat leishmaniasis is characterized by several shortcomings, and resistance has already been reported. Hence, this dramatic background highlights the pressing need to develop novel, affordable, and safe antileishmanial drugs. Multiple classes of natural compounds have been reported to possess antileishmanial activity. Among these classes, iridoids stand out as a special type of monoterpenoids with diverse biological properties-including their antileishmanial potential. This review aims to discuss the available literature between 1991 and 2020 related to the antileishmanial activity of the iridoid class. Throughout the past decades, various investigations attributed antileishmanial action to assorted iridoid types, including inhibitory potential towards validated drug targets and immunomodulatory activity. The latter deserves special attention due to the ability of some iridoids to improve the host's immune response against parasites. It opens the possibility of iridoids become adjuncts in leishmaniasis treatments by improving the efficacy of currently employed drugs. Furthermore, the present study intends to provide a convenient visual representation of which iridoids and Leishmania spp. species have been most investigated as a guide for further researches.

Amarogentin Inhibits Liver Cancer Cell Angiogenesis after Insufficient Radiofrequency Ablation via Affecting Stemness and the p53-Dependent VEGFA/Dll4/Notch1 Pathway

Background

Whether and how amarogentin suppresses the angiogenesis effect in liver cancer cells after insufficient radiofrequency ablation (iRFA) are still poorly studied.

Methods

The number of liver cancer stem cells (LCSCs) and the level of vascular endothelial growth factor A (VEGFA) were assessed in liver cancer tissue after iRFA. Then, CD133-positive cells were detected in iRFA models of HepG2 and Huh7 cell lines treated with amarogentin. Tube formation assays were applied to observe the antiangiogenesis effects of amarogentin. In addition, the angiogenesis-related molecules p53, delta-like ligand 4 (Dll4), and Notch1 were detected in the iRFA cells and mouse models treated with amarogentin.

Results

The mRNA and protein expression levels of CD133 and VEGFA were significantly higher in the residual liver cancer tissue than in the liver cancer tissues treated by hepatectomy. Amarogentin then markedly decreased the percentage of CD133-positive cells in the iRFA model in both HepG2 and Huh7 cell lines. The number of tubules formed by human umbilical vein endothelial cells (HUVECs) was significantly decreased by amarogentin. Inversely, the antiangiogenesis effect of amarogentin was counteracted after p53 silencing in the iRFA cell models.

Conclusion

Amarogentin prevents the malignant transformation of liver cancer after iRFA via affecting stemness and the p53-dependent VEGFA/Dll4/Notch1 pathway to inhibit cancer cell angiogenesis.

Eugenol restricts Cancer Stem Cell population by degradation of β-catenin via N-terminal Ser37 phosphorylation-an in vivo and in vitro experimental evaluation

Eugenol a phenylpropanoid, predominantly found in clove is a very common spice in daily cuisine. It already reported to have anti-breast cancer activity. In this study, the effect of eugenol on CSC (Cancer Stem Cell) markers and its main regulator β-catenin both in vivo Ehrlich Ascites Carcinoma (EAC) cell line and in vitro MCF-7 cell line was investigated with that of the untreated group. The therapeutic doses were found to significantly induce apoptosis leaving normal mice and cells unaffected. The in-depth analysis revealed the downregulation of β-catenin thereby facilitating its degradation by N-terminal phosphorylation of Ser37 residue. Significant downregulation of various CSC markers was also observed in vivo after eugenol treatment those are regulated by the intracellular status of β-catenin. These findings were validated by the effect of eugenol on the formation of the secondary sphere in vitro. Notable downregulation of the enriched stemness of secondary mammosphere was detected by the significantly decreased percentage of CD44⁺/CD24^-/low population after eugenol treatment along with their distorted morphology and smaller the number of spheres. The underlying mechanism revealed significant downregulation of β-catenin and the set of CSC markers along with their reduced mRNA expression in secondary sphere culture. Therefore, it can be concluded from the study that eugenol exerts its chemotherapeutic potential by impeding β-catenin nuclear translocation thereby promoting its cytoplasmic degradation as a result stemness is being suppressed potentially even if in the enriched state. Therefore the study contributes to reduce the cancer-induced complications associated with the CSC population. This will ultimately confer the longer and improved patient's life.

Origin recognition complex subunit 1 regulates cell growth and metastasis in glioma by altering activation of ERK and JNK signaling pathway

Origin recognition complex subunit 1(ORC1) is reported to be closely associated with the cell cycle. However, studies on the role of ORC1 in glioma remain undefined. The aim of the present study was to determine whether ORC1 affects cell migration, invasion, apoptosis, and proliferation and to explore the possible underlying mechanism. GEO database analysis indicated that ORC1 was significantly upregulated in glioma, while Gene set enrichment analysis (GSEA) analysis indicated that ORC1 primarily regulated the cell cycle and affects apoptotic signaling pathways. Analysis of protein-protein interaction (PPI) and gene ontology (GO) to further study the relevant mechanisms revealed that the function of the interaction between proteins and ORC1 was primarily concentrated in the regulation of cell cycle, and apoptosis played a critical role in the whole PPI network. Western blot assay and RT-PCR assay indicated that ORC1 was significantly upregulated in glioma tissues. Western blot assay and RT-PCR indicated that ORC1 was significantly upregulated in glioma cell lines. Cell migration, invasion, apoptosis, and proliferation were detected using Transwell and wound healing assays, flow cytometry, colony formation, and CCK8, respectively. Furthermore, OCR1 inhibition reduced invasion and migration, promoted cell apoptosis. In addition, OCR1 overexpression promoted cell proliferation and induced G2 phase arrest. Moreover, OCR1 downregulation suppressed activation of the ERK/JNK signaling pathway. The effects of ORC1 on biological processes were reversed by ERK and JNK inhibitors. These results indicate that ORC1 could be a novel prognostic marker of glioma via the activation of the ERK/JNK signaling pathway.

Epigallocatechin gallate in combination with eugenol or amarogentin shows synergistic chemotherapeutic potential in cervical cancer cell line

In this study, antitumor activity of epigallocatechin gallate (EGCG; major component of green tea polyphenol), eugenol (active component of clove), and amarogentin (active component of chirata plant) either alone or in combination were evaluated in Hela cell line. It was evident that EGCG with eugenol-amrogentin could highly inhibit the cellular proliferation and colony formation than individual treatments. Induction of apoptosis was also higher after treatment with EGCG in combination with eugenol-amrogentin than individual compound treatments. The antiproliferative effect of these compounds was due to downregulation of cyclinD1 and upregulation of cell cycle inhibitors LIMD1, RBSP3, and p16 at G1/S phase of cell cycle. Treatment of these compounds could induce promoter hypomethylation of LimD1 and P16 genes as a result of reduced expression of DNA methyltransferase 1 (DNMT1). Thus, our study indicated the better chemotherapeutic effect of EGCG in combination with eugenol-amarogentin in Hela cell line. The chemotherapeutic effect might be due to the epigenetic modification particularly DNA hypomethylation through downregulation of DNMT1.

Mechanistic insights into the anticancer mode of action of an herbal drug

Medicinal plants are a vast repository of natural compounds with therapeutic effects against various ailments. Bioactive compounds of these plants have shown to possess anticancer activities. Cancer is one of the fatal diseases causing premature deaths across the world. Two important metabolites, serpentine, a major secondary metabolite of Rauwolfia serpentina, and amarogentin, isolated from Swertia chirata, are found to possess anticancer properties. A comparable in silico analysis of the two anticancer agents serpentine and amarogentin has been done to evaluate their ability to inhibit two potential molecular targets for cancer, nuclear factor-κB (NF-κB) and cyclo-oxygenase-2 (COX-2). The least binding energies of amarogentin with NF-κB and COX-2 are −7·173 and −7·649, respectively, which are better than that of serpentine. The molecular simulation of amarogentin and serpentine suggests that amarogentin has better binding affinities with both cancer targets. Amarogentin is thermodynamically more stable with COX-2 than with NF-κB. Amarogentin is a potent anticancer agent as evidenced by the inhibition of COX-2. This finding would be beneficial to people with cancer.

Amarogentin Induces Apoptosis of Liver Cancer Cells via Upregulation of p53 and Downregulation of Human Telomerase Reverse Transcriptase in Mice

BACKGROUND AND OBJECTIVE

Amarogentin has been reported to have a preventive effect on liver cancer via inducing cancer cell apoptosis. We attempted to elucidate the roles of p53-associated apoptosis pathways in the chemopreventive mechanism of amarogentin. The findings of this study will facilitate the development of a novel supplementary strategy for the treatment of liver cancer.

MATERIALS AND METHODS

The purity of amarogentin was assessed by high-performance liquid chromatography. The inhibitory ratios of the liver cell lines were determined using a Cell Counting Kit-8 following treatment with a gradient concentration of amarogentin. Cell apoptosis was detected by flow cytometry using annexin V-fluorescein isothiocyanate/propidium iodide kits. The gene and protein expression of p53-associated molecules, such as Akt, human telomerase reverse transcriptase, RelA, and p38, was detected by real-time quantitative polymerase chain reaction, Western blotting, and immunohistochemical staining in liver cancer cells and mouse tumor tissues after treatment with amarogentin.

RESULTS

The inhibitory effect of amarogentin on cell proliferation was more obvious in liver cancer cells, and amarogentin was more likely to induce the apoptosis of liver cancer cells than that of normal liver cells. The gene and protein expression levels of Akt, RelA, and human telomerase reverse transcriptase were markedly higher in the control group than in the preventive group and treatment groups. Only the expression of human telomerase reverse transcriptase was downregulated, accompanied by the upregulation of p53.

CONCLUSION

The results of our study suggest that amarogentin promotes apoptosis of liver cancer cells by the upregulation of p53 and downregulation of human telomerase reverse transcriptase and prevents the malignant transformation of these cells.

Phytochemistry and Pharmacological Activities of the Genus Swertia (Gentianaceae): A Review

Swertia plants have been considered to be medicinal plants useful for the treatment of various ailments for thousands of years, especially in Asian countries. This is due to the broad variety of chemical compounds that provide multiple ligands for bonding to different endogenous biomacromolecules for patients. Chemical constituents and pharmacological activities of Swertia plants are summarized in this paper. Approximately 419 metabolites and 40 bioactive compounds have been reported from 30 Swertia species, including xanthones, flavonoids, seco-iridiods, iridiods, triterpenoids, alkaloids, volatiles, and other secondary metabolites. The bioactivities of Swertia plants include anticarcinogenic, hepatoprotective, anti-oxidant, hypoglycemic, anthelmintic, antibacterial, antifungal, anti-diabetic, gut, and airways modulatory, metabolizing isozymes inhibitory, neuroprotective, HIV-I reverse transcriptases inhibitory, anticholinergic, and CNS-depressant activities, etc. In addition, biosynthetic pathways of xanthones, and seco-iridiods, two most important secondary metabolites for Swertia, are elucidated. The xanthones biosynthetic pathway is a mixed biosynthetic pathway involved the shikimate and the malonate routes, and the seco-iridoid pathway starts with geraniol derived from IPP which is produced either via the MEP or the MVA pathway. This review will offer a reference for future researches on the protection of natural resources, the investigation of therapeutic basis, new drug development, and so forth. Metabolic pathways of some crucial active compounds were also discussed in this review.

Protective Effects of Amarogentin against Carbon Tetrachloride-Induced Liver Fibrosis in Mice

Amarogentin, a secoiridoid glycoside that is mainly extracted from Swertia and Gentiana roots, has been suggested to exhibit many biological effects, including anti-oxidative, anti-tumour, and anti-diabetic activities. The present study was designed to evaluate the protective effects of amarogentin on carbon tetrachloride-induced liver fibrosis in vivo and the underlying mechanism. Fibrosis was induced by subcutaneous injections of 6 mL/kg of 20% carbon tetrachloride (dissolved in olive oil) twice per week for seven weeks. Mice were orally treated with 25, 50, and 100 mg/kg amarogentin and with colchicine as a positive control. Biochemical assays and histopathological investigations showed that amarogentin delayed the formation of liver fibrosis; decreased alanine aminotransferase, aspartate aminotransferase, malondialdehyde and hydroxyproline levels; and increased albumin, cyclic guanosine monophosphate, glutathione peroxidase, and superoxide dismutase levels. Moreover, amarogentin exhibited downregulation of α-smooth muscle actin and transforming growth factor-β₁ levels in immunohistochemical and Western blot analyses. The levels of phosphorylated extracellular regulated protein kinases, c-Jun N-terminal kinase, and p38 were also significantly reduced in all amarogentin-treated groups in a dose-dependent manner. These findings demonstrated that amarogentin exerted significant hepatoprotective effects against carbon tetrachloride-induced liver fibrosis in mice and suggested that the effect of amarogentin against liver fibrosis may be by anti-oxidative properties and suppressing the mitogen-activated protein kinase signalling pathway.

High-throughput sequencing and de novo transcriptome assembly of Swertia japonica to identify genes involved in the biosynthesis of therapeutic metabolites

Here, we report potential transcripts involved in the biosynthesis of therapeutic metabolites in Swertia japonica , the first report of transcriptome assembly, and characterization of the medicinal plant from Swertia genus. Swertia genus, representing over 170 plant species including herbs such as S. chirata, S. hookeri, S. longifolia, S. japonica, among others, have been used as the traditional medicine in China, India, Korea, and Japan for thousands of years. Due to the lack of genomic and transcriptomic resources, little is known about the molecular basis involved in the biosynthesis of characteristic key bioactive metabolites. Here, we performed deep-transcriptome sequencing for the aerial tissues and the roots of S. japonica, generating over 2 billion raw reads with an average length of 101 bps. Using a combined approach of three popular assemblers, de novo transcriptome assembly for S. japonica was obtained, yielding 81,729 unigenes having an average length of 884 bps and N50 value of 1452 bps, of which 46,963 unigenes were annotated based on the sequence similarity against NCBI-nr protein database. Annotation of transcriptome assembly resulted in the identification of putative genes encoding all enzymes from the key therapeutic metabolite biosynthesis pathways. Transcript abundance analysis, gene ontology enrichment analysis, and KEGG pathway enrichment analysis revealed metabolic processes being up-regulated in the aerial tissues with respect to the roots of S. japonica. We also identified 37 unigenes as potential candidates involved in the glycosylation of bioactive metabolites. Being the first report of transcriptome assembly and annotation for any of the Swertia species, this study will be a valuable resource for future investigations on the biosynthetic pathways of therapeutic metabolites and their regulations.

Tea polyphenols EGCG and TF restrict tongue and liver carcinogenesis simultaneously induced by N-nitrosodiethylamine in mice

The aim of this study is to understand the molecular mechanisms of N-nitrosodiethylamine (NDEA) induced multi-organ carcinogenesis in tongue and liver of the same mouse and restriction of carcinogenesis by Epigallocatechin gallate (EGCG) and Theaflavin (TF), if any. For that purpose, cellular proliferation/apoptosis, prevalence of CD44 positive stem cell population and expressions of some key regulatory genes of self renewal Wnt and Hedgehog (Hh) pathways and some of their associated genes were analyzed in the NDEA induced tongue and liver lesions in absence or presence of EGCG/TF. Chronic NDEA exposure in oral cavity could decrease mice body weights and induce tongue and liver carcinogenesis with similar histological stages (severe dysplasia up to 30thweeks of NDEA administration). Increasing mice body weights were seen in continuous and post EGCG/TF treated groups. EGCG/TF treatment could restrict both the carcinogenesis at similar histological stages showing potential chemopreventive effect in continuous treated groups (mild dysplasia) followed by pre treatment (moderate dysplasia) and therapeutic efficacy in post treated groups (mild dysplasia) up to 30thweek. The mechanism of carcinogenesis by NDEA and restriction by the EGCG/TF in both tongue and liver were similar and found to be associated with modulation in cellular proliferation/apoptosis and prevalence of CD44 positive population. The up-regulation of self renewal Wnt/β-catenin, Hh/Gli1 pathways and their associated genes Cyclin D1, cMyc and EGFR along with down regulation of E-cadherin seen during the carcinogenesis processes were found to be modulated during the restriction processes by EGCG/TF.

A Review of Swertia chirayita (Gentianaceae) as a Traditional Medicinal Plant

Swertia chirayita (Gentianaceae), a popular medicinal herb indigenous to the temperate Himalayas is used in traditional medicine to treat numerous ailments such as liver disorders, malaria, and diabetes and are reported to have a wide spectrum of pharmacological properties. Its medicinal usage is well-documented in Indian pharmaceutical codex, the British, and the American pharmacopeias and in different traditional medicine such as the Ayurveda, Unani, Siddha, and other conventional medical systems. This ethnomedicinal herb is known mostly for its bitter taste caused by the presence of different bioactive compounds that are directly associated with human health welfare. The increasing high usage of Swertia chirayita, mostly the underground tissues, as well as the illegal overharvesting combined with habitat destruction resulted in a drastic reduction of its populations and has brought this plant to the verge of extinction. The increasing national and international demand for Swertia chirayita has led to unscrupulous collection from the wild and adulteration of supplies. The aim of this review is to provide a synthesis of the current state of scientific knowledge on the medicinal uses, phytochemistry, pharmacological activities, safety evaluation as well as the potential role of plant biotechnology in the conservation of Swertia chirayita and to highlight its future prospects. Pharmacological data reported in literature suggest that Swertia chirayita shows a beneficial effect in the treatment of several ailments. However, there is lack of adequate information on the safety evaluation of the plant. The pharmacological usefulness of Swertia chirayita requires the need for conservation-friendly approaches in its utilization. Providing high-quality genetically uniform clones for sustainable use and thereby saving the genetic diversity of this species in nature is important. In this regard, plant biotechnological applications such as micropropagation, synthetic seed production, and hairy root technology can play a significant role in a holistic conservation strategy. In addition to micropropagation, storage of these valuable genetic resources is equally important for germplasm preservation. However, more advanced research is warranted to determine the activities of bioactive compounds in vitro and in vivo, establish their underlying mechanisms of action and commence the process of clinical research.

Tea polyphenols epigallocatechin gallete and theaflavin restrict mouse liver carcinogenesis through modulation of self-renewal Wnt and hedgehog pathways

The aim of this study is to evaluate chemopreventive and therapeutic efficacy of tea polyphenols epigallocatechin gallete (EGCG) and theaflavin (TF) on self-renewal Wnt and Hedgehog (Hh) pathways during CCl4/N-nitosodiethylamine-induced mouse liver carcinogenesis. For this purpose, the effect of EGCG/TF was investigated in liver lesions of different groups at pre-, continuous and post initiation stages of carcinogenesis. Comparatively increased body weights were evident due to EGCG/TF treatment than carcinogen control mice. Both EGCG and TF could restrict the development of hepatocellular carcinoma at 30th week of carcinogen application showing potential chemoprevention in continuous treated group (mild dysplasia) followed by pretreated (moderate dysplasia) and therapeutic efficacy in posttreated group (mild dysplasia). This restriction was associated with significantly reduced proliferation, increased apoptosis, decreased prevalence of hepatocyte progenitor cell (AFP) and stem cell population (CD44) irrespective of EGCG/TF treatments. The EGCG/TF could modulate the Wnt pathway by reducing β-catenin and phospho-β-catenin-Y-654 expressions along with up-regulation of sFRP1 (secreted frizzled-related protein 1) and adenomatosis polyposis coli during the restriction. In case of the Hh pathway, EGCG/TF could also reduce expressions of glioma-associated oncogene homolog 1 (Gli1) and SMO (smoothened homolog) along with up-regulation of PTCH1 (patched homolog 1). As a result, in Wnt/Hh regulatory pathways decreased expressions of β-catenin/Gli1 target genes like CyclinD1, cMyc and EGFR/phospho-EGFR-Y-1173 and up-regulation of E-cadherin were seen during the restriction. Thus, the restriction of liver carcinogenesis by EGCG/TF was due to reduction in hepatocyte progenitor cell/stem cell population along with modulation of Wnt/Hh and other regulatory pathways.

Contents of therapeutic metabolites in Swertia chirayita correlate with the expression profiles of multiple genes in corresponding biosynthesis pathways

Swertia chirayita, an endangered medicinal herb, contains three major secondary metabolites swertiamarin, amarogentin and mangiferin, exhibiting valuable therapeutic traits. No information exists as of today on the biosynthesis of these metabolites in S. chirayita. The current study reports the expression profiling of swertiamarin, amarogentin and mangiferin biosynthesis pathway genes and their correlation with the respective metabolites content in different tissues of S. chirayita. Root tissues of greenhouse grown plants contained the maximum amount of secoiridoids (swertiamarin, 2.8% of fr. wt and amarogentin, 0.1% of fr. wt), whereas maximum accumulation of mangiferin (1.0% of fr. wt) was observed in floral organs. Differential gene expression analysis and their subsequent principal component analysis unveiled ten genes (encoding HMGR, PMK, MVK, ISPD, ISPE, GES, G10H, 8HGO, IS and 7DLGT) of the secoiridoids biosynthesis pathway and five genes (encoding EPSPS, PAL, ADT, CM and CS) of mangiferin biosynthesis with elevated transcript amounts in relation to corresponding metabolite contents. Three genes of the secoiridoids biosynthesis pathway (encoding PMK, ISPD and IS) showed elevated levels (∼57-104 fold increase in roots), and EPSPS of mangiferin biosynthesis showed an about 117 fold increase in transcripts in leaf tissues of the greenhouse grown plants. The study does provide leads on potential candidate genes correlating with the metabolites biosynthesis in S. chirayita as an initiative towards its genetic improvement.

Evasion of anti-growth signaling: A key step in tumorigenesis and potential target for treatment and prophylaxis by natural compounds

The evasion of anti-growth signaling is an important characteristic of cancer cells. In order to continue to proliferate, cancer cells must somehow uncouple themselves from the many signals that exist to slow down cell growth. Here, we define the anti-growth signaling process, and review several important pathways involved in growth signaling: p53, phosphatase and tensin homolog (PTEN), retinoblastoma protein (Rb), Hippo, growth differentiation factor 15 (GDF15), AT-rich interactive domain 1A (ARID1A), Notch, insulin-like growth factor (IGF), and Krüppel-like factor 5 (KLF5) pathways. Aberrations in these processes in cancer cells involve mutations and thus the suppression of genes that prevent growth, as well as mutation and activation of genes involved in driving cell growth. Using these pathways as examples, we prioritize molecular targets that might be leveraged to promote anti-growth signaling in cancer cells. Interestingly, naturally occurring phytochemicals found in human diets (either singly or as mixtures) may promote anti-growth signaling, and do so without the potentially adverse effects associated with synthetic chemicals. We review examples of naturally occurring phytochemicals that may be applied to prevent cancer by antagonizing growth signaling, and propose one phytochemical for each pathway. These are: epigallocatechin-3-gallate (EGCG) for the Rb pathway, luteolin for p53, curcumin for PTEN, porphyrins for Hippo, genistein for GDF15, resveratrol for ARID1A, withaferin A for Notch and diguelin for the IGF1-receptor pathway. The coordination of anti-growth signaling and natural compound studies will provide insight into the future application of these compounds in the clinical setting.

Modulating Effect of Enicostemma littorale on the Expression Pattern of Apoptotic, Cell Proliferative, Inflammatory and Angiogenic Markers During 7, 12-Dimethylbenz (a) Anthracene Induced Hamster Buccal Pouch Carcinogenesis

Enicostemma littorale leaves are traditionally used for the treatment of several diseases, including inflammation and cancer. This study has taken effort to explore the antitumor initiating potential of E. littorale leaves (ElELet) by analyzing the expression pattern of apoptotic (p53, Bcl-2 and Bcl-2 associated X-protein), cell-proliferative (cyclin D1 and proliferating cell nuclear antigen), angiogenic (vascular endothelial growth factor), invasive (matrix metalloproteinase-2 and 9), and inflammatory (NF-κB and cyclooxygenase-2) markers during 7, 12-dimethylbenz (a) anthracene (DMBA) induced hamster buccal pouch carcinogenesis. Oral tumors were induced in the buccal pouches of hamsters using the potent site and organ specific carcinogen, DMBA. DMBA application 3 times a week for 14 weeks resulted in tumor formation in the buccal pouches. Hundred percent tumor formations with dysregulation in the expression pattern of apoptotic, cell proliferative, inflammatory, angiogenic, and invasive markers were observed in the buccal pouches of hamsters treated with DMBA alone. ElELet at a dose of 250 mg/kg body weight orally to DMBA treated hamsters significantly prevented the tumor formation as well as corrected the abnormalities in the expression pattern of above mentioned molecular markers. ElELet thus modulated the expression pattern of all the above mentioned molecular markers in favor of the suppression of cell proliferation occurring in DMBA induced hamster buccal pouch carcinogenesis.

Prognostic value of differential CCND1 expression in patients with resected gastric adenocarcinoma

Cyclin D1 (CCND1) plays essential roles in cancer progression. In this study, CCND1 expression patterns in 211 cases of resected gastric adenocarcinoma (RGA) tissue were determined by immunohistochemistry, and the association between CCND1 expression levels and RGA prognosis was analyzed. RGA tissues displayed differential CCND1 expression (high expression, 52.1 %; n = 110, and low expression, 47.9 %; n = 101). CCND1 expression levels were related with median overall survival time (MST). MST in patients with high CCND1 expression was 43 months, whereas with low CCND1 expression it was 62 months (P = 0.013). When data were stratified by postoperative treatments and CCND1 expression levels, the MST for patients treated with fluoropyrimidine plus platinum (n = 140) was significantly longer than for those treated with fluoropyrimidine only (n = 71) in both high and low CCND1 expression groups (65.0 vs. 29.0 months, P = 0.041; and 74.5 vs. 33.0 months, P = 0.003, respectively). Cox multivariate analyses further confirmed that high CCND1 expression was related with poor prognosis in both treatment groups [hazard ratio (HR) 1.91, 95 % confidence interval (CI) 1.12-3.23; P = 0.017, and HR 2.14, 95 % CI 1.08-4.25; P = 0.029] and that fluoropyrimidine plus platinum was more effective than fluoropyrimidine only in high CCND1 (HR 0.47, 95 % CI 0.28-0.78; P = 0.004) and low CCND1 (HR 0.44; 95 % CI 0.23-0.82; P = 0.01) expression patients. Therefore, CCND1 may be used as a prognostic biomarker for patients with RGA.

Screening of Antioxidant Activity of Gentian Lutea Root and Its Application in Oil-in-Water Emulsions

Gentiana Lutea root (G. Lutea) is a medicinal herb, traditionally used as a bitter tonic in gastrointestinal ailments for improving the digestive system. The active principles of G. Lutea were found to be secoiridoid bitter compounds as well as many other active compounds causing the pharmacological effects. No study to date has yet determined the potential of G. Lutea antioxidant activity on lipid oxidation. Thus, the aim of this study was to evaluate the effects of an extract of G. Lutea on lipid oxidation during storage of an emulsion. G. Lutea extracts showed excellent antioxidant activity measured by DPPH scavenging assay and Trolox equivalent antioxidant capacity (TEAC) assays. An amount of 0.5% w/w G. Lutea lyophilise was able to inhibit lipid oxidation throughout storage (p < 0.05). A mixture of G. Lutea with 0.1% (w/w) BSA showed a good synergic effect and better antioxidant activity in the emulsion. Quantitative results of HPLC showed that G. Lutea contained secoiridoid-glycosides (gentiopiocroside and sweroside) and post column analysis displayed radical scavenging activity of G. Lutea extract towards the ABTS radical. The results from this study highlight the potential of G. Lutea as a food ingredient in the design of healthier food commodities.

Amarogentin, a secoiridoid glycoside, abrogates platelet activation through PLC γ 2-PKC and MAPK pathways

Amarogentin, an active principle of Gentiana lutea, possess antitumorigenic, antidiabetic, and antioxidative properties. Activation of platelets is associated with intravascular thrombosis and cardiovascular diseases. The present study examined the effects of amarogentin on platelet activation. Amarogentin treatment (15~60  μM) inhibited platelet aggregation induced by collagen, but not thrombin, arachidonic acid, and U46619. Amarogentin inhibited collagen-induced phosphorylation of phospholipase C (PLC) γ2, protein kinase C (PKC), and mitogen-activated protein kinases (MAPKs). It also inhibits in vivo thrombus formation in mice. In addition, neither the guanylate cyclase inhibitor ODQ nor the adenylate cyclase inhibitor SQ22536 affected the amarogentin-mediated inhibition of platelet aggregation, which suggests that amarogentin does not regulate the levels of cyclic AMP and cyclic GMP. In conclusion, amarogentin prevents platelet activation through the inhibition of PLC γ2-PKC cascade and MAPK pathway. Our findings suggest that amarogentin may offer therapeutic potential for preventing or treating thromboembolic disorders.

Nepalese traditional medicine and symptoms related to Parkinson's disease and other disorders: Patterns of the usage of plant resources along the Himalayan altitudinal range

ETHNOPHARMACOLOGICAL RELEVANCE

Nepal is a hotspot for cultural and biological diversities. The tremendous diversity of ecosystems and climates and the blend of medicinal practices inherited from Ayurvedic and Traditional Tibetan Medicine are well suited to a study aimed at discovering information about medicinal plants to treat Parkinson's disease (PD). In addition, this study across Nepal's altitudinal range is relevant to understanding how cultural and ecological environments influence local traditional medicines. The aim of the study is to document the uses of medicinal plants in three different eco-geographical areas of Nepal (Chitwan-Panchase-Mustang) to treat symptoms related to PD. A second goal is to analyze the impact of culture and environment on the evolution of traditional medicine.

MATERIALS AND METHODS

The study was conducted in five communities located in three different eco-geographical environments and at altitudes ranging from 300m to 3700m. We interviewed a total of 56 participants (local people, folk, Ayurvedic and Amchi healers) across the three research areas. We conducted open-ended interviews to document the uses of medicinal plants to treat PD-related symptoms. Information provided by the interviewees suggested that the medicinal plants are also used to treat symptoms related to other disorders. We determined the informant consensus factor as well as the importance of specific plant species to (i) identify plants that are the best candidates to be analyzed experimentally for their potential to treat PD and (ii) perform a cross-cultural comparison of the three areas of study.

RESULTS

This study reports the local uses of 35 different plant species along the Chitwan-Panchase-Mustang altitudinal range. We identify a total of eight plant species that were used in all three research areas, and more specifically one species used to treat PD-like symptoms. We identify a potential dual protective activity of medicinal plants used to treat PD-related symptoms as recent literature suggests that these plants also have anti-cancer properties. In addition, we document that the presence of Ayurvedic healers could influence local practices and that local practices could influence local Ayurvedic practices.

CONCLUSIONS

This study documents the uses of medicinal plants to treat symptoms related to PD and other disorders across the Chitwan-Panchase-Mustang altitudinal range. PD is a neurodegenerative disease affecting a growing number of people worldwide. No cures are available to slow the death of the neurons, and there is a critical need to work towards innovative therapeutic strategies. We identify medicinal plants based on traditional practices to help develop a cure for PD. The three areas of study were chosen for their ecological and cultural diversities, and two of these are included in conservation programs (Panchase Protected Forest and Annapurna Conservation Area). The documentation of community-natural resource relationships is another step in the preservation of traditional practices and local biodiversity and a reflection of communities' rights in the design of conservation programs.

The bitter barricading of prostaglandin biosynthesis pathway: understanding the molecular mechanism of selective cyclooxygenase-2 inhibition by amarogentin, a secoiridoid glycoside from Swertia chirayita

Swertia chirayita, a medicinal herb inhabiting the challenging terrains and high altitudes of the Himalayas, is a rich source of essential phytochemical isolates. Amarogentin, a bitter secoiridoid glycoside from S. chirayita, shows varied activity in several patho-physiological conditions, predominantly in leishmaniasis and carcinogenesis. Experimental analysis has revealed that amarogentin downregulates the cyclooxygenase-2 (COX-2) activity and helps to curtail skin carcinogenesis in mouse models; however, there exists no account on selective inhibition of the inducible cyclooxygenase (COX) isoform by amarogentin. Hence the computer-aided drug discovery methods were used to unravel the COX-2 inhibitory mechanism of amarogentin and to check its selectivity for the inducible isoform over the constitutive one. The generated theoretical models of both isoforms were subjected to molecular docking analysis with amarogentin and twenty-one other Food and Drug Authority (FDA) approved lead molecules. The post-docking binding energy profile of amarogentin was comparable to the binding energy profiles of the FDA approved selective COX-2 inhibitors. Subsequent molecular dynamics simulation analysis delineated the difference in the stability of both complexes, with amarogentin-COX-2 complex being more stable after 40ns simulation. The total binding free energy calculated by MMGBSA for the amarogentin-COX-2 complex was −52.35 KCal/mol against a binding free energy of −8.57 KCal/mol for amarogentin-COX-1 complex, suggesting a possible selective inhibition of the COX-2 protein by the natural inhibitor. Amarogentin achieves this potential selectivity by small, yet significant, structural differences inherent to the binding cavities of the two isoforms. Hypothetically, it might block the entry of the natural substrates in the hydrophobic binding channel of the COX-2, inhibiting the cyclooxygenation step. To sum up briefly, this work highlights the mechanism of the possible selective COX-2 inhibition by amarogentin and endorses the possibility of obtaining efficient, futuristic and targeted therapeutic agents for relieving inflammation and malignancy from this phytochemical source.

Transcriptional and translational regulation of C/EBPβ-HDAC1 protein complexes controls different levels of p53, SIRT1, and PGC1α proteins at the early and late stages of liver cancer

Cancer changes biological processes in the liver by altering gene expression at the levels of transcription, translation, and protein modification. The RNA binding protein CUGBP1 is a key regulator of translation of CCAAT enhancer binding protein β and histone deacetylase 1 (HDAC1). These proteins form complexes that are involved in the regulation of liver biology. Here we show a critical role of the translational activation of CCAAT/enhancer binding protein β-HDAC1 complexes in the development of liver cancer mediated by diethylnitrosamine. We found that diethylnitrosamine increases the levels of CUGBP1 and activates CUGBP1 by phosphorylation, leading to the formation of the CUGBP1-eIF2 complex, which is an activator of translation of CUGBP1-dependent mRNAs. The elevation of the CUGBP1-eIF2 complex increases translation of C/EBPβ and HDAC1, resulting in an increase of C/EBPβ-HDAC1 complexes at later stages of liver cancer. We found that C/EBPβ-HDAC1 complexes repress promoters of three key regulators of liver functions: p53, SIRT1, and PGC1α. As the result of this suppression, the p53-, SIRT1-, and PGC1α-dependent downstream pathways are reduced, leading to increased liver proliferation. We also found that the proper regulation of C/EBPβ-HDAC1 complexes is required for the maintenance of biological levels of p53, SIRT1, and PGC1α in quiescent livers and at early stages of liver cancer. Taken together, these studies showed that the development of liver cancer includes a tight regulation of levels of C/EBPβ-HDAC1 complexes on the levels of transcription, translation, and posttranslational modifications.

Reduction of proliferation and induction of apoptosis are associated with shrinkage of head and neck squamous cell carcinoma due to neoadjuvant chemotherapy

BACKGROUND

Neoadjuvant chemotherapy (NACT) is a treatment modality whereby chemotherapy is used as the initial treatment of HNSCC in patients presenting with advanced cancer that cannot be treated by other means. It leads to shrinkage of tumours to an operable size without significant compromise to essential oro-facial organs of the patients. The molecular mechanisms behind shrinkage due to NACT is not well elucidated.

MATERIALS AND METHODS

Eleven pairs of primary HNSCCs and adjacent normal epithelium, before and after chemotherapy were screened for cell proliferation and apoptosis. This was followed by immunohistochemical analysis of some cell cycle (LIMD1, RBSP3, CDC25A, CCND1, cMYC, RB, pRB), DNA repair (MLH1, p53) and apoptosis (BAX, BCL2) associated proteins in the same set of samples.

RESULTS

Significant decrease in proliferation index and increase in apoptotic index was observed in post-therapy tumors compared to pre-therapy. Increase in the RB/ pRB ratio, along with higher expression of RBSP3 and LIMD1 and lower expression of cMYC were observed in post-therapy tumours, while CCND1 and CDC25A remained unchanged. While MLH1 remained unchanged, p53 showed higher expression in post-therapy tumors, indicating inhibition of cell proliferation and induction of apoptosis. Increase in the BAX/BCL2 ratio was observed in post-therapy tumours, indicating up-regulation of apoptosis in response to therapy.

CONCLUSIONS

Thus, modulation of the G1/S cell cycle regulatory proteins and apoptosis associated proteins might play an important role in tumour shrinkage due to NACT.