Formulation Studies with Cyclodextrins for Novel Selenium NSAID Derivatives.

Commercial cyclodextrins (CDs) are commonly used to form inclusion complexes (ICs) with different molecules in order to enhance their water solubility, stability, and bioavailability. Nowadays, there is strong, convincing evidence of the anticancer effect of selenium (Se)-containing compounds. However, pharmaceutical limitations, such as an unpleasant taste or poor aqueous solubility, impede their further evaluation and clinical use. In this work, we study the enhancement of solubility with CD complexes for a set of different nonsteroidal anti-inflammatory drug (NSAID) derivatives with Se as selenoester or diacyl diselenide chemical forms, with demonstrated antitumoral activity. The CD complexes were analyzed via nuclear magnetic resonance (NMR) spectroscopic techniques. In order to obtain additional data that could help explain the experimental results obtained, 3D models of the theoretical CD-compound complexes were constructed using molecular modeling techniques. Among all the compounds, I.3e and II.5 showed a remarkable increase in their water solubility, which could be ascribed to the formation of the most stable interactions with the CDs used, in agreement with the in silico studies performed. Thus, the preliminary results obtained in this work led us to confirm the selection of ß and γ-CD as the most suitable for overcoming the pharmaceutical drawbacks of these Se derivatives.

Molecular interplay between phytoconstituents of Ficus Racemosa and neurodegenerative diseases.

Neurodegenerative diseases (NDs) are a significant global health concern, primarily affecting middle and older populations. Recently, there has been growing interest in herbal therapeutics as a potential approach to address diverse neuropathological conditions. Despite the widespread prevalence of NDs, limited phytochemical has been reported for their promising therapeutic potential with distinct underlying mechanisms. Additionally, the intricate molecular pathways influenced by herbal phytoconstituents, particularly in neurodegenerative disorders, are also not well documented. This report explores the phytoconstituents of Ficus racemosa (F. racemosa), an unfamiliar plant of the Moraceae family, for their potential interactions with pathological pathways of NDs. The influential phytoconstituents of F. racemosa, including polyphenols, glycosides, terpenoids, and furocoumarin, have been reported for targeting diverse pathological states. We proposed the most convincing molecular interplay between leading phytoconstituents and detrimental signalling cascades. However, extensive research is required to thoroughly understand the phytochemical persuaded intricate molecular pathway. The comprehensive evidence strongly suggests that F. racemosa and its natural compounds could be valuable in treating NDs. This points towards an exciting path for future research and the development of potential treatments based on a molecular level.

An interesting case of unintentional vitamin D toxicity in an infant due to erroneous supplement concentration: a case report.

Despite the rare occurrence of vitamin D toxicity in infants, increased use of vitamin D formulations as well as incorrect supplement concentration by manufacturing pharmaceutical companies, has contributed to an increased incidence of vitamin D toxicity. Over-the-counter vitamin D preparation constitutes variable concentrations that can render life-threatening consequences in children. Case presentation: Here, we present a case of a 2.5-month-old infant presenting with failure to thrive. The clinical presentations were nasal blockage, noisy breathing, poor feeding, lethargy, dehydration, and fever for 3 days with decreased appetite. Her urine culture report showed a urinary tract infection. The biochemical evaluation demonstrated raised total serum calcium (6.0 mmol/l) and serum 25-hydroxy vitamin D (>160 ng/ml) with suppressed parathyroid hormone concentration (3.7 pg/ml), which was the major concern to the clinicians. On ultrasonographical examination, nephrocalcinosis was observed. Further evaluation unveiled that the vitamin D supplement administered to the infant constituted a deucedly high dose of 42 000 IU instead of the recommended dose of 0.5 ml of 800 IU. Clinical discussion: The patient developed vitamin D toxicity after consuming a mega dose of vitamin D supplements due to a manufacturer error. Conclusions: Hypervitaminosis D has severe life-threatening consequences like failure to thrive in otherwise healthy-born infants. Regular monitoring of vitamin D supplements administered in infants by medicinal practitioners and strict supervision of all stages of the production process by pharmaceutical companies is crucial to prevent complications from supplement overdose.

From Natural Sources to Synthetic Derivatives: The Allyl Motif as a Powerful Tool for Fragment-Based Design in Cancer Treatment.

Since the beginning of history, natural products have been an abundant source of bioactive molecules for the treatment of different diseases, including cancer. Many allyl derivatives, which have shown anticancer activity both in vitro and in vivo in a large number of cancers, are bioactive molecules found in garlic, cinnamon, nutmeg, or mustard. In addition, synthetic products containing allyl fragments have been developed showing potent anticancer properties. Of particular note is the allyl derivative 17-AAG, which has been evaluated in Phase I and Phase II/III clinical trials for the treatment of multiple myeloma, metastatic melanoma, renal cancer, and breast cancer. In this Perspective, we compile extensive literature evidence with descriptions and discussions of the most recent advances in different natural and synthetic allyl derivatives that could generate cancer drug candidates in the near future.

Impact of selenium nanoparticles in the regulation of inflammation.

The ability to develop novel medications based on nanoscale complexes has greatly enhanced the capabilities of current pharmaceuticals and has made multidimensional research of these complexes extremely relevant in recent years. Selenium nanoparticles (SeNPs) constitute one such example which in general, could be created by biological, chemical, and physical techniques. Biogenic SeNPs show improved compatibility with human organs and tissues. While sufficient levels of selenium (Se) are crucial for triggering immunity, they also play a role in controlling exaggerated immunological responses and persistent inflammation. More significantly, SeNPs can activate the immune systems, both innate and adaptive, in the tumor microenvironment, which results in an immunological response that fights various diseases caused by chronic inflammation. In this article, we discuss the functions of Se and SeNPs in controlling inflammation with particular emphasis given to their role in combating inflammation in different diseases. Finally, even though Se status exhibits considerable promise as a reliable indicator of autoimmune and inflammatory diseases, novel functionalized SeNPs may likely offer a more effective and reliable tool in both disease prevention and treatment.

Facile synthesis of bromelain copper nanoparticles to improve the primordial therapeutic potential of copper against acute myocardial infarction in diabetic rats.

Our current investigation comprises the synthesis and pharmacological impact of bromelain copper nanoparticles (BrCuNP) against diabetes mellitus (DM) and associated ischemia/reperfusion (I/R) - induced myocardial infarction. Bromelain is a proteolytic enzyme obtained from Ananas comosus L. Merr., which has blood platelet aggregation inhibiting and arterial thrombolytic potential. Moreover, copper is well-known to facilitate glucose metabolism and strengthen cardiac muscle and antioxidant activity; although, chronic or long-term exposure to high doses of copper may lead to copperiedus. To restrict these potential hazards, we synthesized herbal nano-formulation which convincingly indicated the improved primordial therapeutic potential of copper by reformulating the treatment carrier with bromelain, resulting in facile synthesis of BrCuNP. DM was induced by administration of double cycle repetitive dose of low dose streptozotocin (20 mg/kg, i.p.) in high-fat diet- fed animals. DM and associated myocardial I/R injury were estimated by increased serum levels of total cholesterol, low-density lipoprotein, very low-density lipoprotein, lactate dehydrogenase, creatine kinase myocardial band, cardiac troponin, thiobarbituric acid reactive substances, tumor necrosis factor α, interleukin 6, and reduced serum level of high-density lipoprotein and nitrite/nitrate concentration. However, treatment with BrCuNP ameliorates various serum biomarkers by approving cardioprotective potential against DM- and I/R-associated injury. Furthermore, upturn of histopathological changes were observed in cardiac tissue of BrCuNP-treated rats in comparison to disease models.

In Vitro Cytotoxicity of Trastuzumab (Tz) and Se-Trastuzumab (Se-Tz) against the Her/2 Breast Cancer Cell Lines JIMT-1 and BT-474.

Her/2+ breast cancer accounts for ~25% mortality in women and overexpression of Her/2 leads to cell growth and tumor progression. Trastuzumab (Tz) with Taxane is the preferred treatment for Her/2+ patients. However, Tz responsive patients often develop resistance to Tz treatment. Herein, redox selenides (RSe-) were covalently linked to Tz using a selenium (Se)-modified Bolton-Hunter Reagent forming Seleno-Trastuzumab (Se-Tz; ~25 µgSe/mg). Se-Tz was compared to Tz and sodium selenite to assess the viability of JIMT-1 and BT-474 cells. Comparative cell viability was examined by microscopy and assessed by fluorometric/enzymatic assays. Se-Tz and selenite redox cycle producing superoxide (O2•-) are more cytotoxic to Tz resistant JIMT-1 and Tz sensitive BT-474 cells than Tz. The results of conjugating redox selenides to Tz suggest a wider application of this technology to other antibodies and targeting molecules.

Antiurolithic efficacy of a phenolic rich ethyl acetate fraction of the aerial parts of Aerva lanata (Linn) Juss. ex Schult. in ethylene glycol induced urolithic rats.

OBJECTIVES: The study was carried out to evaluate the in vivo antiurolithic efficaciousness of an ethyl acetate fraction of Aerva lanata (EAFAL) derived from the hydromethanolic extract of its aerial parts (HMEAL). METHODS: In vivo pharmacological potency of EAFAL was assessed by ethylene glycol (EG) induced urolithiasis model in male Wistar albino rats. Urine samples of the animals were analysed for physical parameters, stone promoters, inhibitors along with an evaluation of the biochemical parameters of serum and kidneys. Histopathological investigation of the kidneys was done. The fraction was further subjected to LC-MS and HPLC for its phytochemical evaluation. KEY FINDINGS: EAFAL demonstrated a significant antiurolithic effect by a restoration of the balance between urinary promoters and inhibitors along with an amelioration of the urinary pH. The abnormally elevated levels of serum nitrogenous substances, calcium, albumin, globulin, total protein along with altered renal calcium, oxalate and uric acid were also alleviated significantly followed by an improvement of the histopathological aberrancies. Phytochemical analysis showed evidence of phenolic components and flavonoids. CONCLUSIONS: The current findings prove the beneficial role of phenolic and flavonoid rich EAFAL in ameliorating urolithiasis induced abnormalities of urine, serum and kidneys.

New Formulation of a Methylseleno-Aspirin Analog with Anticancer Activity towards Colon Cancer.

Aspirin (ASA) has attracted wide interest of numerous scientists worldwide thanks to its chemopreventive and chemotherapeutic effects, particularly in colorectal cancer (CRC). Incorporation of selenium (Se) atom into ASA has greatly increased their anti-tumoral efficacy in CRC compared with the organic counterparts without the Se functionality, such as the promising antitumoral methylseleno-ASA analog (1a). Nevertheless, the efficacy of compound 1a in cancer cells is compromised due to its poor solubility and volatile nature. Thus, 1a has been formulated with native α-, ß- and γ-cyclodextrin (CD), a modified ß-CD (hydroxypropyl ß-CD, HP-ß-CD) and Pluronic F127, all of them non-toxic, biodegradable and FDA approved. Water solubility of 1a is enhanced with ß- and HP- ß-CDs and Pluronic F127. Compound 1a forms inclusion complexes with the CDs and was incorporated in the hydrophobic core of the F127 micelles. Herein, we evaluated the cytotoxic potential of 1a, alone or formulated with ß- and HP- ß-CDs or Pluronic F127, against CRC cells. Remarkably, 1a formulations demonstrated more sustained antitumoral activity toward CRC cells. Hence, ß-CD, HP-ß-CD and Pluronic F127 might be excellent vehicles to improve pharmacological properties of organoselenium compounds with solubility issues and volatile nature.

Comparative clinical trial of intracameral ropivacaine vs. lignocaine in subjects undergoing phacoemulsification under augmented topical anesthesia.

Purpose: To compare intracameral Ropivacaine to Lignocaine during phacoemulsification under augmented topical anesthesia, in terms of efficacy and safety. Methods: This prospective, randomized, double-masked clinical trial included subjects planned for phacoemulsification with posterior chamber intraocular lens implantation for visually significant uncomplicated senile cataract, under augmented topical anesthesia. Cases were randomized into two groups, Group A (Ropivacaine 0.1%) or Group B (Lignocaine 1.0%). The pain experienced by the patients during the surgery, mydriasis, post-op inflammation and endothelial cell change at six weeks after the procedure was evaluated. Surgeon's feedback was recorded to evaluate the cooperation of the patient during surgery. Results: A total of 210 subjects were screened and 184 were randomized to have 92 subjects in each group. There was no statistically significant difference seen on comparing Group A and B with respect to Age (P = 0.05), painful surgical steps (P = 0.85), visual analog scale scores (P = 0.65), surgeon's score (P = 0.11), postoperative inflammation (P = 0.90) and average ultrasound time during phacoemulsification (P = 0.10). Subjects in Group A fared better when compared to Group B with respect to endothelial cell loss (P = 0.0008), and augmentation in mydriasis (P < 0.001). Conclusion: Intracameral Ropivacaine and Lignocaine, both are equally effective in providing analgesia during phacoemulsification. However, intracameral Ropivacaine is superior to Lignocaine with regards to corneal endothelial cell safety, and augmenting mydriasis.

Nano-medicine and Vascular Endothelial Dysfunction: Options and Delivery Strategies.

The endothelium is a thin innermost layer of flat cells which release various mediators including endothelin-1 (ET-1), prostanoids, von Willebrand factor (vWF) and endothelium-derived relaxing factor (EDRF; nitric oxide) to regulate vascular tone. Endothelial nitric oxide synthase (eNOS) is a key enzyme that generates nitric oxide (NO). NO maintains vascular homeostasis and cardiac functions by influencing major vascular protective properties such as anti-platelet, anti-proliferative, anti-migratory, antioxidant and anti-inflammatory action in vessels. Abnormal endothelial production and release of NO lead to vascular endothelial dysfunction (VED) and further leads to pathogenesis in myocardial and other tissues. Numerous pharmacological agents such as angiotensin-converting enzyme inhibitors, statins, calcium channel blockers, ET-1 receptor antagonists, insulin sensitizers, antioxidants and supplements like tetrahydrobiopterin, arginine and folate have been implicated in the treatment of VED, but their therapeutic potency was restricted due to some unavoidable adverse effects. The new era with advances in nanotechnology and its ability to target a specific disease, nano-medicine explored an innovative gateway for advanced therapy for VED. The present commentary reveals the various available, pipeline nano-medicine, their interaction with endothelium and in other associated pathological conditions and their delivery strategies for target-specific treatment of VED.

Pharmacognostic and pharmacological evaluation of Eulaliopsis binata plant extracts by measuring in vitro/in vivo safety profile and anti-microbial potential.

The present investigation emphasizes the pharmacognostic and phytochemical screening of Eulaliopsis binata and further evaluates the extracts of this plant for toxicological profile and anti-bacterial potential based on in vivo/in vitro assays. Microscopy, powder characteristics of the leaf material, and physicochemical and phytochemical screening were assessed for pharmacognostic evaluation. Dry leaves of Eulaliopsis binata were extracted using different solvents (methanol, ethyl acetate, and hexane), and the extracts obtained were further investigated for in vitro/in vivo toxicological study. Moreover, acute toxicity was assessed by evaluating the anti-oxidant defense system and anatomical damage in vital organs. In addition, anti-bacterial activity of all the extracts was assessed by the Kirby-Bauer method. Physicochemical and microscopic observations showed the unique identification mark for leaf powder and leaf transverse section. Phytochemical investigation evidenced the presence of flavonoids and phenolic contents in the methanolic extract. All extracts were found to be hemocompatible and exhibited no induction of behavioral alteration and no alteration in the anti-oxidant potential and anatomical structure of the vital organs. On the other hand, the methanolic extract showed a significant upsurge in the reduced glutathione level, whereas all extracts showed significant anti-bacterial potential in a dose-dependent manner. Eulaliopsis binata has inimitable pharmacognostical characteristics, good safety profile and significant anti-oxidant and anti-bacterial potential that show immense possibility for its further investigation for pharmacological use.

Cationic amphiphilic bolaamphiphile-based delivery of antisense oligonucleotides provides a potentially microbiome sparing treatment for C. difficile.

Conventional antibiotics for C. difficile infection (CDI) have mechanisms of action without organismal specificity, potentially perpetuating the dysbiosis contributing to CDI, making antisense approaches an attractive alternative. Here, three (APDE-8, CODE-9, and CYDE-21) novel cationic amphiphilic bolaamphiphiles (CABs) were synthesized and tested for their ability to form nano-sized vesicles or vesicle-like aggregates (CABVs), which were characterized based on their physiochemical properties, their antibacterial activities, and their toxicity toward colonocyte (Caco-2) cell cultures. The antibacterial activity of empty CABVs was tested against cultures of E. coli, B. fragilis, and E. faecalis, and against C. difficile by "loading" CABVs with 25-mer antisense oligonucleotides (ASO) targeting dnaE. Our results demonstrate that empty CABVs have minimal colonocyte toxicity until concentrations of 71 µM, with CODE-9 demonstrating the least toxicity. Empty CABVs had little effect on C. difficile growth in culture (MIC90 ≥ 160 µM). While APDE-8 and CODE-9 nanocomplexes demonstrated high MIC90 against C. difficile cultures (>300 µM), CYDE-21 nanocomplexes demonstrated MIC90 at CABV concentrations of 19 µM. Empty CABVs formed from APDE-8 and CODE-9 had virtually no effect on E. coli, B. fragilis, and E. faecalis across all tested concentrations, while empty CYDE-21 demonstrated MIC90 of >160 µM against E. coli and >40 µM against B. fragilisand E. faecalis. Empty CABVs have limited antibacterial activity and they can deliver an amount of ASO effective against C. difficile at CABV concentrations associated with limited colonocyte toxicity, while sparing other bacteria. With further refinement, antisense therapies for CDI may become a viable alternative to conventional antibiotic treatment.

Gambogic acid inhibits multiple myeloma mediated osteoclastogenesis through suppression of chemokine receptor CXCR4 signaling pathways.

Bone disease, characterized by the presence of lytic lesions and osteoporosis is the hallmark of multiple myeloma (MM). Stromal cell-derived factor 1α (SDF-1α) and its receptor, CXC chemokine receptor 4 (CXCR4), has been implicated as a regulator of bone resorption, suggesting that agents that can suppress SDF1α/CXCR4 signaling might inhibit osteoclastogenesis, a process closely linked to bone resorption. We, therefore, investigated whether gambogic acid (GA), a xanthone, could inhibit CXCR4 signaling and suppress osteoclastogenesis induced by MM cells. Through docking studies we predicted that GA directly interacts with CXCR4. This xanthone down-regulates the expression of CXCR4 on MM cells in a dose- and time-dependent manner. The down-regulation of CXCR4 was not due to proteolytic degradation, but rather GA suppresses CXCR4 mRNA expression by inhibiting nuclear factor-kappa B (NF-κB) DNA binding. This was further confirmed by quantitative chromatin immunoprecipitation assay, as GA inhibits p65 binding at the CXCR4 promoter. GA suppressed SDF-1α-induced chemotaxis of MM cells and downstream signaling of CXCR4 by inhibiting phosphorylation of Akt, p38, and Erk1/2 in MM cells. GA abrogated the RANKL-induced differentiation of macrophages to osteoclasts in a dose- and time-dependent manner. In addition, we found that MM cells induced differentiation of macrophages to osteoclasts, and that GA suppressed this process. Importantly, suppression of osteoclastogenesis by GA was mediated through IL-6 inhibition. Overall, our results show that GA is a novel inhibitor of CXCR4 expression and has a strong potential to suppress osteoclastogenesis mediated by MM cells.

Post SELECT: selenium on trial.

Selenium is an essential trace element for humans and other animals that is required in very small amounts for proper growth and functioning. Several selenium compounds have shown promise as cancer chemopreventive and chemotherapeutic agents. However, the negative outcome of the SELECT trial to some extent dampened the enthusiasm of selenium-related drug development. A look at the selenium compounds, their diverse mechanism of action, bioavailability and efficacy based on chemical structure, however, suggests that failure of SELECT that used selenomethionine supplement to prevent prostate cancer was not a failure of selenium compounds as a whole. This is certainly true in regard to therapeutic applications of selenium compounds. This article puts these arguments in perspective, and based on the literature reports, especially several newly developed selenium compounds, emphasizes the importance of selenium in the development of chemopreventive and particularly chemotherapeutic drugs for cancer in near future.

Rational incorporation of selenium into temozolomide elicits superior antitumor activity associated with both apoptotic and autophagic cell death.

BACKGROUND: The DNA alkylating agent temozolomide (TMZ) is widely used in the treatment of human malignancies such as glioma and melanoma. On the basis of previous structure-activity studies, we recently synthesized a new TMZ selenium analog by rationally introducing an N-ethylselenocyanate extension to the amide functionality in TMZ structure. PRINCIPAL FINDINGS: This TMZ-Se analog showed a superior cytotoxicity to TMZ in human glioma and melanoma cells and a more potent tumor-inhibiting activity than TMZ in mouse glioma and melanoma xenograft model. TMZ-Se was also effective against a TMZ-resistant glioma cell line. To explore the mechanism underlying the superior antitumor activity of TMZ-Se, we compared the effects of TMZ and TMZ-Se on apoptosis and autophagy. Apoptosis was significantly increased in tumor cells treated with TMZ-Se in comparison to those treated with TMZ. TMZ-Se also triggered greater autophagic response, as compared with TMZ, and suppressing autophagy partly rescued cell death induced by TMZ-Se, indicating that TMZ-Se-triggered autophagy contributed to cell death. Although mRNA level of the key autophagy gene, Beclin 1, was increased, Beclin 1 protein was down-regulated in the cells treated with TMZ-Se. The decrease in Beclin 1 following TMZ-Se treatment were rescued by the calpain inhibitors and the calpain-mediated degradation of Beclin1 had no effect on autophagy but promoted apoptosis in cells treated with TMZ-Se. CONCLUSIONS: Our study indicates that incorporation of Se into TMZ can render greater potency to this chemotherapeutic drug.

Phenylbutyl isoselenocyanate modulates phase I and II enzymes and inhibits 4-(methylnitrosamino)-1-(3-pyridyl)- 1-butanone-induced DNA adducts in mice.

Lung cancer remains one of the most preventable forms of cancer with about 90% of cases attributed to cigarette smoking. Over the years, the development of chemopreventive agents that could inhibit, delay, or reverse the lung carcinogenesis process has been an active field of research, however, without much attainment. Through extensive structure-activity relationship studies, we recently identified a novel agent phenylbutyl isoselenocyanate (ISC-4), designed on the basis of naturally occurring isothiocyanates well known for their lung cancer prevention properties, as a potential chemopreventive agent. In this study, we used A/J mice to evaluate the lung cancer chemopreventive potential of ISC-4. A single intragastric dose of 1.25 µmol ISC-4 resulted in a time-dependent increase of selenium levels in serum, liver, and lung, suggesting that ISC-4 is orally bioavailable, a key requirement for a chemopreventive agent. This dose also resulted in a time-dependent inhibition of microsomal cytochrome P450 (Cyp450) activity and delayed increases in phase II UDP-glucuronyl transferase (Ugt) and glutathione-S-transferase (Gst) activity. ISC-4 was able to induce mRNA expression of Cyp, Ugt, and Gst enzyme isoforms in liver, but in lung, it inhibited Cyp isoforms while inducing Ugt and Gst isoforms. In addition, ISC-4 effectively inhibited methyl-DNA adduct formation in mice fed diet supplemented with ISC-4 for two weeks and then treated with the tobacco procarcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone. These results suggest that ISC-4 is a strong candidate for development as a chemopreventive agent.

Synthesis of isosteric selenium analog of the PPARbeta/delta agonist GW501516 and comparison of biological activity.

Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors and members of the nuclear hormone receptor superfamily. Herein, we describe an efficient synthesis of a novel isosteric selenium analog of the highly specific PPARbeta/delta ligand 2-methyl-4-((4-methyl-2-(4-trifluoromethylphenyl)-1,3-thiazol-5-yl)-methylsulfanyl)phenoxy-acetic acid (GW501516; 1). The study examined the efficiency of the novel selenium analog 2-methyl-4-((4-methyl-2-(4-trifluoromethylphenyl)-1,3-selenazol-5-yl)-methylsulfanyl)phenoxy-acetic acid (2) to activate PPARbeta/delta and the effect of ligand activation of PPARbeta/delta on cell proliferation and target gene expression in human HaCaT keratinocytes. The results showed that similar to GW501516, the Se-analog 2 increased expression of the known PPARbeta/delta target gene angiopoietin-like protein 4 (ANGPTL4); the compound 2 was comparable in efficacy as compared to GW501516. Consistent with a large body of evidence, the Se-analog inhibited cell proliferation in HaCaT keratinocytes similar to that observed with GW501516. In summary, the novel Se-analog 2 has been developed as a potent PPARbeta/delta ligand that may possess additional anti-cancer properties of selenium.

Plants as bioreactors: Recent developments and emerging opportunities.

In recent years, the use of plants as bioreactors has emerged as an exciting area of research and significant advances have created new opportunities. The driving forces behind the rapid growth of plant bioreactors include low production cost, product safety and easy scale up. As the yield and concentration of a product is crucial for commercial viability, several strategies have been developed to boost up protein expression in transgenic plants. Augmenting tissue-specific transcription, elevating transcript stability, tissue-specific targeting, translation optimization and sub-cellular accumulation are some of the strategies employed. Various kinds of products that are currently being produced in plants include vaccine antigens, medical diagnostics proteins, industrial and pharmaceutical proteins, nutritional supplements like minerals, vitamins, carbohydrates and biopolymers. A large number of plant-derived recombinant proteins have reached advanced clinical trials. A few of these products have already been introduced in the market.

Genome analysis and genetic enhancement of tomato.

The Solanaceae is an important family of vegetable crops, ornamentals and medicinal plants. Tomato has served as a model member of this family largely because of its enriched cytogenetic, genetic, as well as physical, maps. Mapping has helped in cloning several genes of importance such as Pto, responsible for resistance against bacterial speck disease, Mi-1.2 for resistance against nematodes, and fw2.2 QTL for fruit weight. A high-throughput genome-sequencing program has been initiated by an international consortium of 10 countries. Since heterochromatin has been found to be concentrated near centromeres, the consortium is focusing on sequencing only the gene-rich euchromatic region. Genomes of the members of Solanaceae show a significant degree of synteny, suggesting that the tomato genome sequence would help in the cloning of genes for important traits from other Solanaceae members as well. ESTs from a large number of cDNA libraries have been sequenced, and microarray chips, in conjunction with wide array of ripening mutants, have contributed immensely to the understanding of the fruit-ripening phenomenon. Work on the analysis of the tomato proteome has also been initiated. Transgenic tomato plants with improved abiotic stress tolerance, disease resistance and insect resistance, have been developed. Attempts have also been made to develop tomato as a bioreactor for various pharmaceutical proteins. However, control of fruit quality and ripening remains an active and challenging area of research. Such efforts should pave the way to improve not only tomato, but also other solanaceous crops.