Lignans: a versatile source of anticancer drugs.

Background: Cancer is considered as the second deadliest disease globally. Plants have continuously offered unique secondary metabolites with remarkable biological applications. Lignans have gained great importance due to their biological activity. Previous studies revealed that the most remarkable bioactivity of lignan class of molecules is anticancer. They are derived from the oxidative dimerization of two phenylpropanoid units. This review covers the isolated anticancer lignans and their mechanistic aspects. Main body: A bibliographic investigation was performed by analyzing the information available on anticancer lignans in the internationally accepted scientific databases including Web of Science, SciFinder, PubMed, Scopus, and Google Scholar. In this review we have tried to sum up the isolated anticancerous lignan, its source, active plant part, extract and various cell lines used to establish different studies. Here we have included a total number of 113 natural lignans. Many studies that mainly performed in human cell lines have reported. Very few plants have been evaluated for their in vivo anticancer activity. Conclusion: It can be concluded that in near future the lignans may be an effective pharmacon for the treatment of cancer. Fruitful areas of future research may be in modifying natural lignans or synthesizing new lignans with structural diversity and potent pharmacological activities. Extensive studies are needed to be done highlighting the mechanism of anticancer action of explored and unexplored plants. The data will definitely attract many researchers to start further experimentation that might lead to the drugs for the cancer treatment.

Development and characterization of spheroidal antidiabetic polyherbal formulation from fresh vegetable juice: A novel approach.

Polyherbal Formulations (PHF) were developed by combining fruit juices of Momordica charantia, Cucumis sativus, and Solanum lycopersicum in different ratios and optimized through Oral Glucose Tolerance Test (OGTT) model. PHF-C pretreated rats showed the highest reduction of Serum Glucose Levels (SGL) after 60 min of glucose administration. PHF-C was incorporated into spheroids using fresh juice (FJS) and lyophilized powder (LPS) of selected plants. In OGTT study, LPS showed a significant reduction of SGL. LPS was characterized as almost spherical, having disintegration time 8 min, adequate friability, and good flow properties. In STZ-induced diabetic rats on 7th, 14th, and 21st days, LPS was reduced SGL by 9.01%, 20.9%, 38.9% (250 mg/kg dose); 20.5%, 33.9%, and 50.7% (500 mg/kg dose), respectively. LPS showed a significant improvement in abnormal body weight, biochemical, and oxidative parameters in comparison to PHF-C and metformin. Novel formulation LPS (500 mg/kg) was found more effective (p < .05) in reversing STZ-induced hyperglycemia as compared to PHF-C (1,000 mg/kg) and at par with metformin (500 mg/kg). PRACTICAL APPLICATIONS: Fresh vegetable juice contains large quantities of vitamins and minerals. Cooking and processing of fruits may destroy their nutritional value. However, FJS also has some limitations, including seasonal specificity, patient compliance, less stability, loss of vitamins and fibers, abnormal sugar level, weak immunity, and difficult to carry by patients. Lyophilization is a well-known method to improve the physical state, shelf life, and stability of phytoconstituents. Poor absorption and less bioavailability also impede the acceptance of PHF. To overcome these limitations, a suitable novel drug delivery system is required which has high therapeutic efficacy and enhanced bioavailability. The patented spheroids of herbal extracts which are in use for the treatment of the number of diseases encouraged the present work. Spheroid protects the constituents of herbal drugs from gastric destruction and gut bacteria. The outcome of present research supports the concept of enhanced stability and bioavailability of phytoconstituents present in FJS.

Bioactive Lignans from Zanthoxylum alatum Roxb. stem bark with cytotoxic potential.

ETHNOPHARMACOLOGICAL RELEVANCE: Zanthoxylum alatum is used in traditional medicinal systems for number of disorders like cholera, diabetes, cough, diarrhea, fever, headache, microbial infections, toothache, inflammation and cancer. The aim of the present study was to evaluate Zanthoxylum alatum stem bark for its cytotoxic potential and to isolate the bioactive constituents. MATERIAL AND METHODS: Cytotoxicity of the different extracts and isolated compounds was studied on lung carcinoma cell line (A549) and pancreatic carcinoma cell line (MIA-PaCa) using MTT assay. Isolation of compounds from most active extract (petroleum ether) was done on silica gel column. Structure elucidation was done by using various spectrophotometric techniques like UV, IR, (1)H NMR, (13)C NMR and mass spectroscopy. The type of cell death caused by most active compound C was explored by fluorescence microscopy using the acridine orange/ethidium bromide method. RESULT: Petroleum ether extract of plant has shown significant cytotoxic potential. Three lignans sesamin (A), kobusin (B), and 4'O demethyl magnolin (C) has been isolated. All lignans showed cytotoxic activities in different ranges. Compound C was the novel bioactive compound from a plant source and found to be most active. In apoptosis study, treatment caused typical apoptotic morphological changes. It enhances the apoptosis at IC50 dose (21.72 µg/mL) however showing necrotic cell death at higher dose after 24h on MIA-PaCa cell lines. CONCLUSION: Petroleum ether extract (60-80 °C) of Zanthoxylum alatum has cytotoxic potential. The lignans isolated from the petroleum ether extract were responsible for the cytotoxic potential of the extract. 4'O demethyl magnolin was novel compound from Zanthoxylum alatum. Hence the Zanthoxylum alatum can be further explored for the development of anticancer drug.