Phytochemical portfolio and anticancer activity of Murraya koenigii and its primary active component, mahanine

An alkaloid enriched fraction from Murraya koenigii (L.) Spreng. Leaves ameliorate HFD-induced obesity and metabolic complexities in C57BL/6J mice

ETHNOPHARMACOLOGICAL RELEVANCE

Murraya koenigii commonly known as curry leaf, is traditionally used in India to manage various ailments including diabetes mellitus. Curry leaves are well documented in Indian Ayurvedic system of medicine for beneficial effects in skin eruptions, dysentery, emesis, poisonous bites and bruises. The anti-hyperglycemic and anti-hyperlipidemic effects of curry leaf extracts have been demonstrated through several in vitro and in vivo experiments previously.

AIM OF THE STUDY

To prepare an alkaloid enriched fraction (AEF) from M. koenigii and its evaluation on i) in vitro adipogenesis process and ii) in vivo high fat diet-induced obesity in C57BL/6J mice.

MATERIALS AND METHODS

MKME and AEF were prepared from M. koenigii leaves. The four carbazole alkaloids (bioactive markers) isolated from AEF were quantitatively determined in the leaves by RP-HPLC method. MKME and AEF were studied for anti-obesogenic activity in adipocytes in vitro and in HFD-induced C57BL/6J obese mice in vivo. At the termination of the in vivo study, lipid profile, hepatic and renal injury and glucose levels were analyzed in the blood samples. Animal tissues were examined histopathologically to determine any signs of damage. Repeated dose oral toxicity study for 28 days on Sprague-Dawley rats was also performed to determine the safety profile of AEF.

RESULTS

Both MKME and AEF displayed anti-obesogenic activity at 25 μg/ml concentration in vitro and showed 54.06 ± 3.86% and 37.46 ± 3.17% lipid accumulation, respectively compared to control. Further, supplementation of AEF and MKME in HFD-fed C57BL/6J mice helped in controlling weight gain, improved dyslipidemia and glucose intolerance significantly. AEF showed better anti-obesity activity than MKME both in vitro and in vivo study. Repeated administration of AEF up to 1 g/kg dose for 28 days showed no pathological tissue damage. Both MKME and AEF were standardized using a simple and validated RP-HPLC method.

CONCLUSION

Present study was aimed at preparation of a novel alkaloid-enriched fraction from methanolic extract of M. koenigii leaf and its evaluation for anti-diabesity effect. Our results demonstrated AEF to be a promising plant-based therapy for ameliorating obesity and related metabolic complications in HFD-fed C57BL/6J mice.

A review of natural products and small-molecule therapeutics acting on central nervous system malignancies: Approaches for drug development, targeting pathways, clinical trials, and challenges

In 2021, the World Health Organization released the fifth edition of the central nervous system (CNS) tumor classification. This classification uses histopathology and molecular pathogenesis to group tumors into more biologically and molecularly defined entities. The prognosis of brain cancer, particularly malignant tumors, has remained poor worldwide, approximately 308,102 new cases of brain and other CNS tumors were diagnosed in the year 2020, with an estimated 251,329 deaths. The cost and time-consuming nature of studies to find new anticancer agents makes it necessary to have well-designed studies. In the present study, the pathways that can be targeted for drug development are discussed in detail. Some of the important cellular origins, signaling, and pathways involved in the efficacy of bioactive molecules against CNS tumorigenesis or progression, as well as prognosis and common approaches for treatment of different types of brain tumors, are reviewed. Moreover, different study tools, including cell lines, in vitro, in vivo, and clinical trial challenges, are discussed. In addition, in this article, natural products as one of the most important sources for finding new chemotherapeutics were reviewed and over 700 reported molecules with efficacy against CNS cancer cells are gathered and classified according to their structure. Based on the clinical trials that have been registered, very few of these natural or semi-synthetic derivatives have been studied in humans. The review can help researchers understand the involved mechanisms and design new goal-oriented studies for drug development against CNS malignancies.

Mahanine mediated therapeutic inhibition of estrogen receptor-α and CDK4/6 expression, decipher the chemoprevention-signaling cascade in preclinical model of breast cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Mahanine (MH), a naturally occurring carbazole alkaloid, isolated from Ayurvedic medicinal plant Murraya koenigii (L.) Spreng, has been shown to have various pharmacological properties, including its inhibitory activity against different breast cancers (BC) subtypes.

AIM OF THE STUDY

While MH triggers apoptosis in BC cells regardless of subtype, the specific mechanism of MH action is not fully understood. In this study, we show the effect of MH in preventing BC progression by inducing apoptosis in relation to estrogen receptor-α (ERα) and cell cycle regulatory proteins.

MATERIALS AND METHODS

To assess the pharmacological activity in various in vitro and in vivo tests, isolated and pure MH was used. To conclude the study, cutting edged molecular biology techniques including Western blot analysis, enzyme-linked immunosorbent assay (ELISA), molecular simulation study, and other related software analysis were employed.

RESULTS

MH demonstrated dose dependent cell viability against drug sensitive (MCF-7 and MDA-MB-231) and paclitaxel resistant (MCF-7TR and MDA-MB-231TR) BC cells. MH also exhibited synergistic activity with tamoxifen (TAM) against estrogen receptor positive (ER+) BC cells by inhibiting ERα expression in MCF-7 cells and N-Methyl-N-nitrosourea (MNU)-induced mammary tumor in a dose-dependent manner while having no effect on vinculin expression. In addition, MH inhibited cell cycle regulatory genes namely CDK1/CDK4/CDK6/CDC25A and neo-angiogenesis through downregulation of CD31/PECAMs in MCF-7, MDA-MB-231 cells and mammary tumors from MNU-induced rats. MH therapy has been shown to be significantly able to lower the serum leptin level and to be beneficial against the initiation of tumor development in SD rats for up to 12 weeks. Molecular modeling study revealed that MH has antagonized the effectiveness of several types of estrogen those bind to the ERα and has comparable binding efficacy to TAM.

CONCLUSION

Overall, the current investigation showed the ability of MH to modify cell cycle genes especially CDK4 and CDK6 might be responsible for its anticancer activity against different breast cancer subtypes. Additionally, this study will aid in advancing MH translational research to the clinical trial stage.

Mechanisms and regulation of defensins in host defense

As a family of cationic host defense peptides, defensins are mainly synthesized by Paneth cells, neutrophils, and epithelial cells, contributing to host defense. Their biological functions in innate immunity, as well as their structure and activity relationships, along with their mechanisms of action and therapeutic potential, have been of great interest in recent years. To highlight the key research into the role of defensins in human and animal health, we first describe their research history, structural features, evolution, and antimicrobial mechanisms. Next, we cover the role of defensins in immune homeostasis, chemotaxis, mucosal barrier function, gut microbiota regulation, intestinal development and regulation of cell death. Further, we discuss their clinical relevance and therapeutic potential in various diseases, including infectious disease, inflammatory bowel disease, diabetes and obesity, chronic inflammatory lung disease, periodontitis and cancer. Finally, we summarize the current knowledge regarding the nutrient-dependent regulation of defensins, including fatty acids, amino acids, microelements, plant extracts, and probiotics, while considering the clinical application of such regulation. Together, the review summarizes the various biological functions, mechanism of actions and potential clinical significance of defensins, along with the challenges in developing defensins-based therapy, thus providing crucial insights into their biology and potential clinical utility.

Metabolomic approach for phytochemical assessment of Murraya koenigii fruits during different maturity stages

A detailed metabolomic study was performed on various maturation stages of Murraya koenigii fruit pulps, seed, and leaf. Among the fruit pulps, stage 6 had the highest TPC (13.27 mg/g of GAE) and TFC content (6.16 mg/g RE). The extracts also showed promising free radical scavenging activity, especially in the seed (IC50DPPH 427 μg/mL). Metabolomics study revealed the identification of 133 metabolites in fruit pulps, seeds and leaves using the METLIN database. In silico PASS software analysis predicted the antimutagenic property of myricetin and bismurrayaquinone A. Pathway analysis revealed the phenylpropanoid biosynthesis pathway as one of the major pathways present in the fruit pulps. This detailed metabolic report of M. koenigii fruit maturation report brings a new insight into phytochemicals and their distribution in seed, pulps and leaves along with nutritive values and can be considered for nutritive and therapeutic purposes.

Extract of Murraya koenigii selectively causes genomic instability by altering redox-status via targeting PI3K/AKT/Nrf2/caspase-3 signaling pathway in human non-small cell lung cancer

BACKGROUND

Lung cancer is the leading cause of cancer-related death worldwide. Dietary bioactives have been used as alternative therapeutics to overcome various adverse effects caused by chemotherapeutics. Curry leaves are a widely used culinary spice and different parts of this plant have been used in traditional medicines. Curry leaves are a rich source of multiple bioactives, especially polyphenols and alkaloids. Therefore, extraction processes play a key role in obtaining the optimum yield of bioactives and their efficacy.

PURPOSE

We aim to select an extraction process that achieves the optimum yield of bioactives in curry leaves crude extract (CLCE) with minimum solvent usage and in a shorter time. Further, to investigate the anticancer properties of CLCE and its mechanism against lung cancer.

METHODS

Different extraction processes were performed and analyzed polyphenol content. The bioactives and essential oils present in curry leaves were identified through LC-MS/MS and GC-MS analysis. The cytotoxicity of microwave-assisted CLCE (MA-CLCE) was investigated through MTT and colony-forming assays. The DNA damage was observed by comet assay. The apoptotic mechanisms of MA-CLCE were investigated by estimating ROS production, depolarization of mitochondrial membrane potential (MMP), and apoptotic proteins. The glutathione assay estimated the antioxidant potential of MA-CLCE in normal cells.

RESULTS

Generally, conventional extraction methods require high temperatures, extra energy input, and time. Recently, green extraction processes are getting wider attention as alternative extraction methods. This study compared different extraction processes and found that the microwave-assisted extraction (MAE) method yields the highest polyphenols from curry leaves among other extraction processes with minimum processing. The MA-CLCE functions as an antioxidant under normal physiological conditions but pro-oxidant to cancer cells. MA-CLCE scavenges free radicals and enhances the intracellular GSH level in alveolar macrophages in situ. We found that MA-CLCE selectively inhibits cell proliferation and induces apoptosis in cancer cells by altering cellular redox status. MA-CLCE induces chromatin condensation and genotoxicity through ROS-induced depolarization of MMP. The depolarization of MMP causes the release of cytochrome c into the cytosol and activates the apoptotic pathway in lung cancer cells. However, pretreatment with ascorbic acid, an antioxidant, inhibits the MA-CLCE-induced apoptosis by reducing ROS production, which impedes mitochondrial membrane disruption, preventing BAX/BCL-2 expression alteration. Simultaneously, MA-CLCE downregulates the expression of survival signaling regulator PI3K/AKT, which modulates Nrf-2. MA-CLCE also diminishes intracellular antioxidant proficiency by suppressing Nrf-2 expression, followed by HO-1 expressions.

CONCLUSION

Among several extraction methods, MA-CLCE is rich in several bioactives, especially polyphenols, alkaloids, and essential oils. Here, we reported for the first time that MA-CLCE functions as a pro-oxidant to lung cancer cells and acts as an antioxidant to normal cells by regulating different cellular programs and signaling pathways. Therefore, it can be further developed as a promising phytomedicine against lung cancer.

Dietary phytochemicals/nutrients as promising protector of breast cancer development: a comprehensive analysis

Genetic change, particularly epigenetic alteration, is one of the imperative factors for sporadic breast cancer development in the worldwide population of women. The DNA methylation process is essential and natural for human cellular renewal and tissue homeostasis, but its dysregulation contributes to many pathological changes, including breast tumorigenesis. Chemopreventive agents mainly protect the abnormal DNA methylation either by hindering the division of pre-malignant cells or looming the DNA damage, which leads to malignancy. The present review article is about understanding the potential role of dietary phytochemicals in breast cancer prevention. Accordingly, a literature search of the published article until August 2021 has been performed. Further, we have investigated the binding affinity of different phytochemicals isolated from diverse dietary sources against the various oncogenic proteins related to breast cancer initiation to understand the common target(s) in breast cancer prevention mechanisms. Various small phytochemicals, especially dietary phytochemicals including sulforaphane, mahanine, resveratrol, linolenic acid, diallyl sulfide, benzyl/phenethyl isothiocyanate, etc. are being investigated as the chemopreventive agent to manage breast cancer development, and some of them have shown promising outcomes in the cited research. In this present review, we discuss the recent advancement in acceptance of such types of potential dietary phytochemicals as a chemopreventive agent against breast cancer development and their inner lining mechanism. The critical clinical trials and cohort studies have also been considered to understand the progress in contemporary perspectives.

Multi-Target Approach of Murraya koenigii Leaves in Treating Neurodegenerative Diseases

Neurodegenerative diseases (NDs) mainly affect neurons and gradually lead to a loss of normal motor and cognitive functions. Atypical protein homeostasis-misfolding, aggregations and accumulations, oxidative stress, inflammation, and apoptosis-are common features in most NDs. To date, due to the complex etiology and pathogenesis of NDs, no defined treatment is available. There has been increasing interest in plant extracts as potential alternative medicines as the presence of various active components may exert synergistic and multi-pharmacological effects. Murraya koenigii (Rutaceae) is utilized in Ayurvedic medicine for various ailments. Pharmacological studies evidenced its potential antioxidant, anti-inflammatory, anticancer, hepatoprotective, immunomodulatory, antimicrobial, and neuroprotective activities, among others. In line with our interest in exploring natural agents for the treatment of neurodegenerative diseases, this review presents an overview of literature concerning the mechanisms of action and the safety profile of significant bioactive components present in M. koenigii leaves to support further investigations into their neuroprotective therapeutic potential.

Identification of microRNAs from Medicinal Plant Murraya koenigii by High-Throughput Sequencing and Their Functional Implications in Secondary Metabolite Biosynthesis

MicroRNAs (miRNAs) are small noncoding RNA molecules that play crucial post-transcriptional regulatory roles in plants, including development and stress-response signaling. However, information about their involvement in secondary metabolism is still limited. Murraya koenigii is a popular medicinal plant, better known as curry leaves, that possesses pharmaceutically active secondary metabolites. The present study utilized high-throughput sequencing technology to investigate the miRNA profile of M. koenigii and their association with secondary metabolite biosynthesis. A total of 343,505 unique reads with lengths ranging from 16 to 40 nt were obtained from the sequencing data, among which 142 miRNAs were identified as conserved and 7 as novel miRNAs. Moreover, 6078 corresponding potential target genes of M. koenigii miRNAs were recognized in this study. Interestingly, several conserved and novel miRNAs of M. koenigii were found to target key enzymes of the terpenoid backbone and the flavonoid biosynthesis pathways. Furthermore, to validate the sequencing results, the relative expression of eight randomly selected miRNAs was determined by qPCR. To the best of our knowledge, this is the first report of the M. koenigii miRNA profile that may provide useful information for further elucidation of the involvement of miRNAs in secondary metabolism. These findings might be crucial in the future to generate artificial-miRNA-based, genetically engineered M. koenigii plants for the overproduction of medicinally highly valuable secondary metabolites.

Nutritive Importance and Therapeutics Uses of Three Different Varieties (Murraya koenigii, Micromelum minutum, and Clausena indica) of Curry Leaves: An Updated Review

Murraya koenigii (M. koenigii), Micromelum minutum (M. minutum), and Clausena indica (C. indica) are three varieties of curry leaves in the family Rutaceae. They have been widely used in Ayurvedic medicine worldwide in the treatment and prevention of various diseases. Earlier findings provide strong evidence to support the three curry leaf species' potent pharmaceutical and biological effects, including antioxidant, antidiabetic, anti-inflammatory, and antitumor activities. Various parts of these plants, such as leaves, seeds, flowers, and fruit, contain constituents responsible for the modulation of numerous biological processes. Leading constituents of curry leaves play a crucial role in diabetic and anticancer management by regulating various molecular pathways, including Bcl-2, Bax, NF-κB, and TNFα, according to in vitro and in vivo models established. Therefore, this review summarizes the current knowledge on research achievements made in terms of phytoconstituents, their structures, biological activities, and pharmacological actions with clinical studies of curry leaves up to date. The review also emphasizes the necessity for comprehensive research studies on the pharmacological actions and the mechanisms of selected phytochemicals of M. koenigii, M. minutum, and C. indica to validate their efficacy as potent herbal remedies for many ailments.

Three Active Phytotoxic Compounds from the Leaves of Albizia richardiana (Voigt.) King and Prain for the Development of Bioherbicides to Control Weeds

The global population is increasing day by day. To meet the food demand for such a huge number of people, crop production must increase without damaging the environment, and to prevent synthetic chemical herbicides from polluting the environment, controlling weeds using bioherbicides is essential. Accordingly, using phytotoxic substances obtained from plants for biological weed management has attracted attention. The plant Albizia richardiana possesses phytotoxic compounds that have been previously recorded. Hence, we have conducted this research to characterize more phytotoxic compounds in Albizia richardiana. Aqueous methanolic extracts of Albizia richardiana plant significantly restricted the growth of the examined plants lettuce and Italian ryegrass in a species- and concentration-dependent manner. Three active phytotoxic compounds were isolated through various chromatographic methods and identified as compound 1, 2, and 3. Compound 3 exhibited stronger phytotoxic potentials than the other two compounds and significantly suppressed the growth of Lepidium sativum (cress). The concentration of the compounds required for 50% growth reduction (I₅₀ value) of the Lepidium sativum seedlings ranged between 0.0827 to 0.4133 mg/mL. The results suggest that these three phytotoxic compounds might contribute to the allelopathic potential of Albizia richardiana.

The anticancer activity of carbazole alkaloids

Chemotherapy is the first choice for the majority of cancers, but severe side effects and drug resistance restrict the actual clinical efficacy. Carbazole alkaloids, mainly from the Rutaceae family, possess favorable donor ability, good planarity, rich photophysical properties, and excellent biocompatibility. Carbazole alkaloids could not only intercalate in DNA but could also inhibit telomerase and topoisomerase and regulate protein phosphorylation. Hence, carbazole alkaloids are useful in providing lead hits/candidates for the development of novel anticancer agents. This review summarizes the research progress made regarding the anticancer properties of carbazole alkaloids, covering articles published from January 2010 to June 2021.

Phytochemical screening, total polyphenol, flavonoid content, in vitro antioxidant and antibacterial activities of Sri Lankan varieties of Murraya koenigii and Micromelum minutum leaves

The use of plant materials in traditional medicine as a significant ingredient in synthesizing drugs in the form of decoctions had played a vital role due to their potential therapeutic action. The curry leaves, Murraya koenigii, and Micromelum minutum are two most common aromatic herbs widespread in Sri Lanka and many other Asian countries. They are rich in nutrition and exert several medicinal properties such as antidiabetic, antioxidant, antimicrobial, anti-inflammatory, and anti-carcinogenic due to various essential phytochemicals, minerals, and trace minerals. In this study, we determined the proximate composition, in vitro antioxidant activity, total phenol (TPC), flavonoid content (TFC), and antibacterial activity in both species using standard methods. Results showed that both species varied greatly in nutritional composition, antioxidant, and antibacterial activities. The nutrient composition in terms of ash, crude protein, and fat was significantly high in M. koenigii based on dry weight basis. In vitro antioxidant potential of M. koenigii and M. minutum was evaluated by means of the DPPH radical scavenging assay, and the IC₅₀ values of M. koenigii and M. minutum were 107 ± 2 μg/mL and 208 ± 4 μg/mL, respectively. The TPC and TFC of M. koenigii were 101 ± 1 mg GAE/g and 9.75 ± 0.05 mg QE/g, and M. minutum were 80 ± 2 mg GAE/g and 9.16 ± 0.02 mg QE/g respectively. The antibacterial study was assessed against three bacterial strains. The study showed the highest inhibitory activity for M. koenigii and M. minutum against Staphylococcus aureus and Escherichia coli, respectively at 1.0 mg/mL concentration. The study indicated that M. koenigii possessed a significantly high TPC, and TFC correlated with higher antibacterial and antioxidant activity than M. minutum.

A Review of the Anti-Cancer Potential of Murraya koenigii (Curry Tree) and Its Active Constituents

Murraya koenigii (MK) relates to the Rutaceae family and has many health benefits. To date, over eighty-eight carbazole alkaloids along with terpenoids, and other nutrients have been identified from different parts of this plant. This review presents accumulated information regarding the role of MK and its constituents in the prevention/treatment of cancer. Literature survey revealed that MK and its constituents target multiple deranged pathways associated with apoptosis, growth (JAK-STAT, mTOR), and cell cycle in a variety of cancerous cell lines (colon, lung, liver, skin, prostate, breast, etc.) and few animal models. Thus, the present review highlights the anticancer mechanism of MK and its phytoconstituents, and further future perspectives. The ameliorating effects of MK and its phytoconstituents against various cancers warrant its multi-institutional clinical trials as soon as possible. The prospects of relatively cheaper cancer drugs could then be brighter, particularly for the socio-economically feebler cancer patients of the world.

Variation in biosynthesis of an effective anticancer secondary metabolite, mahanine in Murraya koenigii, conditional on soil physicochemistry and weather suitability

Murraya koenigii (MK) leaf being a rich source of bioactive secondary metabolites has received inordinate attention in drug development research. Formation of secondary plant metabolite(s) in medicinal plants depends on several factors and in this study the cause of variation in bioavailability and content of a vital bioactive phytochemical, mahanine in the MK leaves from different geographical locations of varying soil properties and weather parameters was determined. Accordingly, MK leaves and soil samples around the plant base in quintuplicate from each site across five states of India at similar time point were collected. Mahanine content was determined and compared among samples from different regions. The quantitative analysis data comprised that MK-leaves of southern part of India contains highest amount of mahanine, which is 16.9 times higher than that of MK-leaves of north-eastern part of India (which measured as the lowest). The results suggested that pH, conductivity and bacterial populations of the soil samples were positively correlated with mahanine content in the MK-leaves. For examples, the average soil pH of the southern India sites was in basic range (8.8 ± 0.6); whereas that of the north-east India sites was in slightly acidic ranges (6.1 ± 0.5) and mean soil conductivity value for the north east India soils was 78.3 ± 16.3 µS/cm against mean value of 432.4 ± 204.5 µs/cm for south India soils. In conclusion, this study proclaims that higher level of bioactive phytochemical, mahanine in MK leaves depending upon geographical location, weather suitability and soil’s physiochemical and microbial parameters of its cultivation sites.

Mukonal exerts anticancer effects on the human breast cancer cells by inducing autophagy and apoptosis and inhibits the tumor growth in vivo

Mukonal is an active member of carbazole alkaloids isolated from Murraya koenigii. It has been shown to possess remarkable biological and pharmacological activities including anticancer activity. Therefore, the aim of current investigation was to explore anti-breast cancer activity of mukonal and to explore the underlying mechanism. Results indicate that mukonal has potential to induce antiproliferative effects against MDA-MB-231 and SK-BR-3 cells with an IC₅₀ of 7.5 µM. No significant toxicity of mukonal was observed in case of normal breast cells. The antiproliferative effects of mukonal were found to proceed via apoptosis, which was further supported by increased cleavage of PARP and caspase-3 and reduced expression of Bcl-2. Mukonal induced autophagic cells death in breast cancer cells as was evidenced by formation of autophagosomes and enhanced expressions of Beclin-1, LC3B-I and LC3B-II proteins. In vivo examination of anti-breast cancer property of mukonal indicated that it could potentially reduce tumor weight and volume in xenografted mice models. In conclusion, mukonal has a remarkable potential of inhibiting breast cancer via induction of apoptosis and autophagy. Mukonal also inhibited xenografted tumors models in a dose-dependent manner. Therefore, mukonal may prove lead molecule in breast cancer drug discovery and treatment provided further investigations are recommended.

Medicinal Profile, Phytochemistry, and Pharmacological Activities of Murraya koenigii and its Primary Bioactive Compounds

The discovery of several revitalizing molecules that can stop or reduce the pathology of a wide range of diseases will be considered a major breakthrough of the present time. Available synthetic compounds may provoke side effects and health issues, which heightens the need for molecules from plants and other natural resources under discovery as potential methods of replacing synthetic compounds. In traditional medicinal therapies, several plant extracts and phytochemicals have been reported to impart remedial effects as better alternatives. Murraya koenigii (M. koenigii) belongs to the Rutaceae family, which is commonly used as a medicinally important herb of Indian origin in the Ayurvedic system of medicine. Previous reports have demonstrated that the leaves, roots, and bark of this plant are rich sources of carbazole alkaloids, which produce potent biological activities and pharmacological effects. These include antioxidant, antidiabetic, anti-inflammatory, antitumor, and neuroprotective activities. The present review provides insight into the major components of M. koenigii and their pharmacological activities against different pathological conditions. The review also emphasizes the need for more research on the molecular basis of such activity in various cellular and animal models to validate the efficacy of M. koenigii and its derivatives as potent therapeutic agents.

Mahanine, A dietary phytochemical, represses mammary tumor burden in rat and inhibits subtype regardless breast cancer progression through suppressing self-renewal of breast cancer stem cells

Mahanine (MH), a carbazole alkaloid isolated from an edible plant (Murraya koenigii), potentially inhibits the growth of altered subtypes of breast cancer cells in vitro and significantly reduced the mammary tumor burden in N-Methyl-N-nitrosourea (MNU) induced rat. The experimental results showed that 20-25 μM of MH for 24 h of treatment was very potent to reduce the cell proliferation through apoptosis with arresting the cells in G₀/G₁ in both ER⁺/p53^WT MCF-7 and triple negative/p53^Mut MDA-MB-231 cells. On the other hand, 10-15 μM of MH exposure to those two cell lines, caused inhibition of mammosphere formation and reduction of CD44^high/CD24^low/epithelial-specific antigen-positive (ESA+) population, which ultimately led to loss of self-renewal ability of breast cancer stem cells. Further, in vivo observation indicated that intraperitoneal injection of MH for four weeks with a dose of 50 mg/kg body weight thrice in a week, significantly (P =  0.03) reduced the mammary tumor weight in MNU induced rat. In conclusion, this study provides the novel insight into the mechanism of MH mediated growth arrest in subtype irrespective breast cancer progression.

Modulation of cerulein-induced pancreatic inflammation by hydroalcoholic extract of curry leaf (Murraya koenigii)

This study was performed to study the in vitro and in vivo efficacy of hydroalcoholic extract of curry leaf (CLE) rich in carbazole alkaloids, against LPS-induced inflammation in Raw 264.7 macrophages and cerulein-induced acute pancreatitis, respectively. CLE was characterized by Fourier-transform infrared (FTIR) and liquid chromatography-mass spectrometry. Raw 264.7 cells were stimulated with LPS (2 μg/ml) and treated with CLE. The animals were treated with two doses of CLE (100 and 300 mg/kg). Plasma biochemistry, tissue lipid peroxidation, cytokines, and histological examination were evaluated. CLE was found to decently scavenge the activity of DPPH radical. It dose dependently suppressed nitrite production and oxidative stress in macrophages. CLE alleviated LPS-induced inflammation in macrophages as evident from the results of various inflammatory cytokines (IL-1β, IL-6, and TNF-α). In vivo, CLE reduced cerulein-induced pancreatic edema. CLE significantly abrogated the cerulein-induced lipid peroxidation, nitrite, MPO, and GSH levels. The inflammatory cytokines and p65-NFκB activity were significantly reduced by CLE. Mechanistically, CLE reduced the expression of NT, MPO, IL-1β, ICAM-1, and COX-2, and increased the expression of Nrf2. It reduced distant organ damage markers as well. We report for the first time that CLE holds substantial potential for the prevention of acute pancreatitis.

Murrayanine Induces Cell Cycle Arrest, Oxidative Stress, and Inhibition of Phosphorylated p38 Expression in A549 Lung Adenocarcinoma Cells

Background

Murrayanine is a carbazole alkaloid derived from Murraya koenigii, which has been used in traditional Chinese medicine in the treatment of cancer. This study aimed to investigate the effects of murrayanine on human lung adenocarcinoma cells in vitro and to investigate the mechanisms of its action.

Material/Methods

A549 human lung adenocarcinoma cells and MRC-5 human lung fibroblasts were grown in culture, and an MTT assay determined cell viability. Cells were treated for 24 h with increasing doses of murrayanine (0, 9, 18, and 36 μM). Fluorescence, using 4′, 6-diamidino-2-phenylindole (DAPI), acridine orange, ethidium bromide, and propidium iodide (PI), were used for the detection of apoptosis. The cell cycle was studied with fluorescence-activated cell sorting (FACS), and Western blot evaluated protein expression.

Results

Murrayanine treatment resulted in significant dose-dependent inhibition of the growth of A549 cells (p<0.05), with an IC₅₀ of 9 μM, and arrested the cells at the G2/M phase of the cell cycle, reduced the expression of cyclin D and E, CDK2, 4, and 6, and increased the expression of p21 and p27. Murrayanine treatment increased apoptosis of the A549 cells and increased cleaved of caspase-3 and caspase-9, and the Bax/Bcl-2 ratio. Murrayanine treatment increased levels of reactive oxygen species (ROS), disrupted the mitochondrial membrane potential, inhibited invasion, and inhibited phosphorylation of p38 mitogen-activated protein kinase (MAPK) of the A549 cells.

Conclusions

Murrayanine induced cell cycle arrest, oxidative stress, and inhibited the expression of phosphorylated p38 in A549 adenocarcinoma cells.

Mukonal Inhibits Cell Proliferation, Alters Mitochondrial Membrane Potential and Induces Apoptosis and Autophagy in Human CNE1 Nasopharyngeal Carcinoma Cells

Background

Nasopharyngeal carcinoma results in high patient morbidity and mortality, due to early metastasis, and toxicity due to chemotherapy. Mukonal is plant-derived carbazole alkaloid that has been used in traditional Chinese medicine to treat several types of cancer. This study aimed to investigate the effects of mukonal on cell proliferation, apoptosis, autophagy, and the mitochondrial membrane potential of nasopharyngeal carcinoma cells in vitro.

Material/Methods

CNE1 human nasopharyngeal carcinoma cells and NP69 normal nasopharyngeal epithelial cells were cultured with and without treatment with increasing doses of mukonal. Cell viability was determined by the MTT assay. Fluorescence microscopy was used to detect reactive oxygen species (ROS), mitochondrial membrane potential, and the release of cytochrome C. Flow cytometry was used to examine changes in the cell cycle, electron microscopy examined cell autophagy, and Western blot was performed to measure levels of proteins associated with autophagy and apoptosis.

Results

Mukonal had an antiproliferative effect on CNE1 cells, with an IC₅₀ of 9 μM and there were effects of toxicity on normal NP69 cells. Mukonal triggered ROS-mediated changes in mitochondrial membrane potential which was also accompanied by the discharge of cytochrome C in the CNE1 cells. Mukonal activated autophagy and apoptosis in CNE1 cells, which was also associated with upregulation of the autophagy-related proteins, LC3 II and beclin-1, as well as apoptosis-associated proteins, Bax, cleaved caspase-3 and -9. Mukonal treatment also resulted in CNE1 cells cycle arrest at G₂/M.

Conclusions

Mukonal inhibited the growth of human CNE1 nasopharyngeal carcinoma cells in vitro.

Mahanine induces apoptosis, cell cycle arrest, inhibition of cell migration, invasion and PI3K/AKT/mTOR signalling pathway in glioma cells and inhibits tumor growth in vivo

Gliomas are among the most frequent types of primary malignancies in the central nervous system. The main treatment for glioma includes surgical resection followed by a combination of radiotherapy and chemotherapy. Despite the availability of several treatments, the average survival for patients with glioma at advanced stages still remains 16 months only. Therefore, there is an urgent need to look for novel and more efficient drug candidates for the treatment of glioma. In the current study the anticancer activity of Mahanine was evaluated against a panel of glioma cells. The results revealed that Mahanine exerted significant anticancer effects on the glioma HS 683 cells with an IC₅₀ of 7.5 μM. However, the cytotoxic effects were less pronounced on the normal human astrocytes. Further the results showed that the anticancer effects were mainly due to induction of apoptosis and G2/M cell cycle arrest. Western blotting showed that Mahanine caused upregulation of Bax, cytochrome c, cleaved caspase 3 and 9 and cleaved PARP. However, the expression of cell cycle related proteins pCdc25c, Cdc25c, pCdc2, Cdc2 and cyclin B1 was significantly downregulated. The effect of Mahanine on the migration and invasion of HS 683 cells was also determined and results indicated that Mahanine inhibited the cell migration and invasion at IC₅₀. Additionally, Mahanine-inhibited cell growth was simultaneous with suppression of p-PI3K, p-AKT and p-mTOR. Taken together these results indicate that Mahanine may prove to be an important lead molecule for the treatment of glioma and warrants further investigation.

Anticancer Activity of Mukonal Against Human Laryngeal Cancer Cells Involves Apoptosis, Cell Cycle Arrest, and Inhibition of PI3K/AKT and MEK/ERK Signalling Pathways

Background

Laryngeal cancer is one of the major malignancies of the neck and head and is responsible for considerable mortality across the globe. The treatments for laryngeal cancer mainly involve surgical interventions followed by chemotherapy. However, due to unsatisfactory results, constant relapses and the adverse effects associated with the currently used drugs, there is pressing need to develop effective drug options for treatment of laryngeal cancer. Therefore, this study was undertaken to investigate the anticancer effects of a plant-derived alkaloid, Mukonal, against human AMC-HN-8 laryngeal cancer cells.

Material/Methods

The WST-1 and clonogenic assays were employed to determine the cell viability. Apoptosis was detected by Hoechst and AO/EB staining. Cell migration and cell cycle analysis was performed by Transwell assay and flow cytometry, respectively. Protein expression was examined by Western blotting.

Results

The results revealed that Mukonal reduced the viability of laryngeal cancer cells dose-dependently. The IC₅₀ of Mukonal was found to be 10 μM. However, the effects of Mukonal on the normal HuLa-PC cells was found to be 140 μM. The decrease in the viability of the AMC-HN-8 laryngeal cancer cells was found to be due to the induction of apoptosis and G2/M cell cycle arrest. Mukonal also suppressed the cell migration and of the AMC-HN-8 laryngeal cancer cells. Mukonal could also inhibit the PI3K/AKT and MEK/ERK signalling pathways in a concentration-dependent manner.

Conclusions

Taken together, we conclude that Mukonal could prove a beneficial lead molecule for the treatment of laryngeal cancer.

Citrus fruits intake and oral cancer risk: A systematic review and meta-analysis

OBJECTIVE

To quantify the relationship between Citrus intake and risk of cancer of the oral cavity and pharynx.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Ovid MEDLINE, EMBASE, and Web of Science were searched until September 2017. Search terms included Citrus, Citrus aurantifolia, Citrus sinensis, Citrus paradisi, Citrus fruits, Citrus fruits extract, Citrus oil, fruits, oral cancer, mouth cancer, mouth neoplasm.

STUDY SELECTION

The selection of studies and the systematic review were carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A pre-defined inclusion checklist resulted in the inclusion of articles which were (i) published in peer-reviewed scientific journals; (ii) English language; (iii) and included a measure of Citrus fruit intake and risk of oral and pharyngeal cancer. Studies were excluded if (i) preparations derived from other fruits were used, (ii) Citrus intake was combined with intake of other fruits; (iii) in vitro or animal models were used. We also excluded reviews, systematic reviews, meta-analyses, letters, personal opinions, conference abstracts and book chapters.

DATA EXTRACTION

Three reviewers independently performed the extraction of data from studies included.

RESULTS

Seventeen studies met our inclusion criteria and were included in the final review. Pooled analyses showed that those with the highest Citrus fruit intake compared to the lowest intake had a 50% reduction in risk of oral cavity and pharyngeal cancer (OR 0.50; 95% CI 0.43-0.59).

CONCLUSION

The studies included in this review and meta-analysis showed an inverse association between Citrus fruit intake and oral cancer.