B.R. Sindhura

Bio: B.R. Sindhura is an academic researcher from Karnatak University. The author has contributed to research in topics: Cell & Cytotoxic T cell. The author has an hindex of 3, co-authored 3 publications receiving 26 citations.

Lectins: Magic Bullet towards HIV Gp120

Abstract: The AIDS epidemic, in spite of considerable efforts is continuous to spread at formidable rate worldwide with an estimated 34 million people being infected with HIV at the end of 2010. Drug discovery towards AIDS is a desperation area of research because of the down beating results of number of painstaking attempts. The key step in the disease progression is viral binding to the host T lymphocytes and entry. The gp120 and gp41 glycoproteins, derived from gp160 forms a complex that mediates the receptor and co receptor binding, subsequent membrane fusion events will permits viral entry.

Overview of the Structure–Function Relationships of Mannose-Specific Lectins from Plants, Algae and Fungi

Abstract: To date, a number of mannose-binding lectins have been isolated and characterized from plants and fungi. These proteins are composed of different structural scaffold structures which harbor a single or multiple carbohydrate-binding sites involved in the specific recognition of mannose-containing glycans. Generally, the mannose-binding site consists of a small, central, carbohydrate-binding pocket responsible for the "broad sugar-binding specificity" toward a single mannose molecule, surrounded by a more extended binding area responsible for the specific recognition of larger mannose-containing N-glycan chains. Accordingly, the mannose-binding specificity of the so-called mannose-binding lectins towards complex mannose-containing N-glycans depends largely on the topography of their mannose-binding site(s). This structure⁻function relationship introduces a high degree of specificity in the apparently homogeneous group of mannose-binding lectins, with respect to the specific recognition of high-mannose and complex N-glycans. Because of the high specificity towards mannose these lectins are valuable tools for deciphering and characterizing the complex mannose-containing glycans that decorate both normal and transformed cells, e.g., the altered high-mannose N-glycans that often occur at the surface of various cancer cells.

Triphenylamine flanked furan-diketopyrrolopyrrole for multi-imaging guided photothermal/photodynamic cancer therapy.

Abstract: The combination of photodynamic therapy (PDT) and photothermal therapy (PTT) is highly desired to improve the cancer phototherapeutic effect. However, most reported multicomponent therapeutic agents need complex preparation processes and must be excited by using multiple light sources. Herein, triphenylamine flanked furan-diketopyrrolopyrrole (FDPP-TPA) with a donor–acceptor–donor structure has been synthesized and used as a sole-component agent for fluorescence, photoacoustic and photothermal imaging guided photodynamic and photothermal synergistic therapy. FDPP-TPA nanoparticles (NPs) obtained by re-precipitation exhibit a high molar extinction coefficient (e = 2.13 (±0.2) × 104 M−1 cm−1), excellent photothermal conversion efficiency (η = 47%) and favorable singlet oxygen quantum yield (ΦΔ(X) = 40%). In vitro, the half-maximal inhibitory concentration (IC50) is 13 μg mL−1 determined by cytotoxicity assay. And the apoptosis rate is 67.3% according to flow cytometry analysis. In vivo, the tumor can be completely ablated without recurrence, which suggests that FDPP-TPA NPs can generate considerable poisonous singlet oxygen and hyperthermia for tumor treatment.

Chemical diversity and activity profiles of HIV-1 reverse transcriptase inhibitors from plants

Abstract: Current challenges to antiretroviral therapy have opened new vistas in the search for novel drugs from natural products. This review focusses on plants as sources of inhibitors for human immunodeficiency virus type 1 (HIV-1) reverse transcriptase. Based on a systematic search of the literature, anti-HIV-1 reverse transcriptase activity was recorded for 132 plant species in 100 genera and 51 families. Seven families comprise 52.6% of plant species with anti-reverse transcriptase activity: Lamiaceae (13.7%), Fabaceae (10.7%), Euphorbiaceae (9.9%), Clusiaceae (6.1%), Asteraceae (4.6%), Combretaceae (4.6%), and Moraceae (3.0%). The repertoire of anti-reverse transcriptase active compounds includes (-)-catechin, 1,8-cineole, 3,4-di-O-caffeoylquinic acid, 5,7-dimethoxy-6-methylflavone, apigenin, baicalein, betulinic acid, caffeic acid, cis-3-hexene-1-ol, eugenol, euscaphic acid, gallic acid, hoslunddiol, limonene, naringenin, oleanolic acid, p-cymene, pomolic acid, quinic acid, rosmarinic acid, stigmasterol, thymol, ursolic acid, α-bergamotene, α-pinene, and γ-terpinene. Among the IC50 values are 0.10 μg/ml (Uvaria angolensis), 3 μg/ml (Hemidesmus indicus), 2. 3μg/ml (Adansonia digitata), 6.24 μg/ml (Caesalpinia coriaria), 7.2 μg/ml (Terminalia sericea), 17.4 μg/ml (Hypoxis hemerocallidea), and 79 μg/ml (Moringa oleifera). The chemical diversity and activity profiles of HIV-1 reverse transcriptase inhibitors from plants reveal two recurring motifs: the structure of several active anti-reverse transcriptase compounds mimics nucleoside analogues, and numerous anti-reverse transcriptase phytochemicals have pleiotropic effects and heterogenous pharmacological benefits during infection and disease. To accelerate drug discovery and development, this review recommends the urgent need to tap into the rich vein of indigenous knowledge of putative anti-HIV/AIDS medicinal plants (reverse pharmacology), determine pan-assay interference compounds, analyze structure-activity relationships, and conduct more clinical trials.

Plant-Derived Lectins as Potential Cancer Therapeutics and Diagnostic Tools.

Abstract: Cancer remains a global health challenge, with high morbidity and mortality, despite the recent advances in diagnosis and treatment. Multiple compounds assessed as novel potential anticancer drugs derive from natural sources, including microorganisms, plants, and animals. Lectins, a group of highly diverse proteins of nonimmune origin with carbohydrate-binding abilities, have been detected in virtually all kingdoms of life. These proteins can interact with free and/or cell surface oligosaccharides and might differentially bind cancer cells, since malignant transformation is tightly associated with altered cell surface glycans. Therefore, lectins could represent a valuable tool for cancer diagnosis and be developed as anticancer therapeutics. Indeed, several plant lectins exert cytotoxic effects mainly by inducing apoptotic and autophagic pathways in malignant cells. This review summarizes the current knowledge regarding the basis for the use of lectins in cancer diagnosis and therapy, providing a few examples of plant-derived carbohydrate-binding proteins with demonstrated antitumor effects.

Dioscorea Plants: A Genus Rich in Vital Nutra-pharmaceuticals-A Review.

Abstract: Dioscorea species, known as "Yams," belong to family Dioscoreaceae. This genus consists of more than 600 species distributed from Africa, Asia, the Caribbean's South America, and the South Pacific islands. Their organoleptic properties make them the most widely used carbohydrate food and dietary supplements. The underground and/or aerial tubers represent valuable sources of proteins, fats, and vitamins for millions of people in West Africa. This review gives a shot of secondary metabolites of Dioscorea plants, including steroids, clerodane diterpenes, quinones, cyanidins, phenolics, diarylheptanoids, and nitrogen-containing compounds. This review collected the evidence on biological properties of description Dioscorea, including in-vitro and in-vivo studies. Dioscorea species contain promising bioactive molecules i.e. diosgenin that support their different biological properties, including antioxidant, hypoglycaemic, hypolipidemic, anti- antimicrobial, inflammatory, antiproliferative, androgenic, estrogenic, and contraceptive drugs. Indeed, besides its nutrient values, Dioscorea is a potential source of bioactive substances of interest in the prevention/treatment of several diseases, and thus represents a great challenge in developing countries. However, ethnomedicinal potential should be validated and further researches on pharmacological properties and phytochemical composition should be carried out. Particularly, doing some studies to convert the preclinical results to clinical efficacy should be guaranteed. Dioscorea, Food plant, Traditional use, Phytochemistry, Pharmacological activities.