scholarly journals A glimpse on biological activities of tellurium compounds

2009 ◽  
Vol 81 (3) ◽  
pp. 393-407 ◽  
Author(s):  
Rodrigo L. O. R. Cunha ◽  
Iuri E. Gouvea ◽  
Luiz Juliano

Tellurium is a rare element which has been regarded as a toxic, non-essential trace element and its biological role is not clearly established to date. Besides of that, the biological effects of elemental tellurium and some of its inorganic and organic derivatives have been studied, leading to a set of interesting and promising applications. As an example, it can be highlighted the uses of alkali-metal tellurites and tellurates in microbiology, the antioxidant effects of organotellurides and diorganoditellurides and the immunomodulatory effects of the non-toxic inorganic tellurane, named AS-101, and the plethora of its uses. Inasmuch, the nascent applications of organic telluranes (organotelluranes) as protease inhibitors and its applications in disease models are the most recent contribution to the scenario of the biological effects and applications of tellurium and its compounds discussed in this manuscript.

2021 ◽  
Vol 2021 ◽  
pp. 1-20
Author(s):  
Jie Lu ◽  
Jing Tian ◽  
Li Zhou ◽  
Lijun Meng ◽  
Sitan Chen ◽  
...  

Poria is a common Traditional Chinese Medicine in clinic. In recent years, the chemical and pharmacological studies of Poria have made great progress, triterpenes and polysaccharides have been isolated, and various types of compounds containing lipids, octanoic acids, fatty acids, and trace elements have been found. In this paper, we reviewed the literature, summarized the main compound types, and reviewed in detail their pharmacological effects in antitumor, immunomodulatory, effects on kidney, hepatoprotective activity, effects on blood sugar, antioxidant effects, anti-inflammatory effects, effects on the gut, antidepressant, and so on, and also categorized the compounds with the same or similar pharmacological effects to provide a reference for the in-depth study of the material basis of the pharmacological effect, quality standards, and pharmacological activity of Poria.


2018 ◽  
Vol 25 (14) ◽  
pp. 1663-1681 ◽  
Author(s):  
Chun-Ting Lee ◽  
Heng-Chun Kuo ◽  
Yung-Hsiang Chen ◽  
Ming-Yen Tsai

The polysaccharides in many plants are attracting worldwide attention because of their biological activities and medical properties, such as anti-viral, anti-oxidative, antichronic inflammation, anti-hypertensive, immunomodulation, and neuron-protective effects, as well as anti-tumor activity. Denodrobium species, a genus of the family orchidaceae, have been used as herbal medicines for hundreds of years in China due to their pharmacological effects. These effects include nourishing the Yin, supplementing the stomach, increasing body fluids, and clearing heat. Recently, numerous researchers have investigated possible active compounds in Denodrobium species, such as lectins, phenanthrenes, alkaloids, trigonopol A, and polysaccharides. Unlike those of other plants, the biological effects of polysaccharides in Dendrobium are a novel research field. In this review, we focus on these novel findings to give readers an overall picture of the intriguing therapeutic potential of polysaccharides in Dendrobium, especially those of the four commonly-used Denodrobium species: D. huoshanense, D. offininale, D. nobile, and D. chrysotoxum.


2004 ◽  
Vol 69 (3) ◽  
pp. 499-510 ◽  
Author(s):  
Petra Beranová ◽  
Karel Chalupský ◽  
Gustav Entlicher

Nω-Hydroxy-L-arginine (NOHA) is a stable intermediate in NO formation from L-arginine catalyzed by NO synthase (NOS). Apparently, NOHA can be released and serve as a stable reserve NO donor (as a substrate of NOS) or transported and exert its own biological effects. It shows endothelium-dependent as well as endothelium-independent vasorelaxant activity. The latter case indicates that NOHA can be metabolized by pathways independent of NOS. These possibilities are discussed in detail. Of the available NOHA homologues homo-NOHA is a good substrate of NOS while nor-NOHA seems to be a very poor substrate of this enzyme. On the contrary, nor-NOHA exerts arginase inhibitory activity 20 times higher than NOHA whereas homo-NOHA is inactive. Detailed investigation of biological activities of NOHA and its homologues seems to be promising from the pharmacological point of view. A review with 43 references.


Biomolecules ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 542
Author(s):  
Gustavo Penteado Battesini Carretero ◽  
Greice Kelle Viegas Saraiva ◽  
Magali Aparecida Rodrigues ◽  
Sumika Kiyota ◽  
Marcelo Porto Bemquerer ◽  
...  

In a large variety of organisms, antimicrobial peptides (AMPs) are primary defenses against pathogens. BP100 (KKLFKKILKYL-NH2), a short, synthetic, cationic AMP, is active against bacteria and displays low toxicity towards eukaryotic cells. BP100 acquires a α-helical conformation upon interaction with membranes and increases membrane permeability. Despite the volume of information available, the action mechanism of BP100, the selectivity of its biological effects, and possible applications are far from consensual. Our group synthesized a fluorescent BP100 analogue containing naphthalimide linked to its N-terminal end, NAPHT-BP100 (Naphthalimide-AAKKLFKKILKYL-NH2). The fluorescence properties of naphthalimides, especially their spectral sensitivity to microenvironment changes, are well established, and their biological activities against transformed cells and bacteria are known. Naphthalimide derived compounds are known to interact with DNA disturbing related processes as replication and transcription, and used as anticancer agents due to this property. A wide variety of techniques were used to demonstrate that NAPHT-BP100 bound to and permeabilized zwitterionic POPC and negatively charged POPC:POPG liposomes and, upon interaction, acquired a α-helical structure. Membrane surface high peptide/lipid ratios triggered complete permeabilization of the liposomes in a detergent-like manner. Membrane disruption was driven by charge neutralization, lipid aggregation, and bilayer destabilization. NAPHT-BP100 also interacted with double-stranded DNA, indicating that this peptide could also affect other cellular processes besides causing membrane destabilization. NAPHT-BP100 showed increased antibacterial and hemolytic activities, compared to BP100, and may constitute an efficient antimicrobial agent for dermatological use. By conjugating BP100 and naphthalimide DNA binding properties, NAPHT-BP100 bound to a large extent to the bacterial membrane and could more efficiently destabilize it. We also speculate that peptide could enter the bacteria cell and interact with its DNA in the cytoplasm.


Planta Medica ◽  
2021 ◽  
Author(s):  
Jerald Nair ◽  
Johannes Van Staden

The Amaryllidaceae features prominently amongst bulbous flowering plant families. Accommodating about a third of its species, South Africa affords a sound basis for Amaryllidaceae plant research. Boophone, Nerine, Crossyne, Clivia, Cryptostephanus, Haemanthus and Scadoxus have been well-represented in such endeavors. The account herein summarizes the studies undertaken between 2013-2020 on these genera in regards to their chemical and biological characteristics. A total of 136 compounds comprising 63 alkaloids and 73 non-alkaloid entities were described during this period from eighteen members of the title genera. The alkaloids were reflective of the structural diversity found in eight isoquinoline alkaloid groups of the Amaryllidaceae. Of these, the crinane (29 compounds), lycorane and homolycorine (11 compounds each) groups were the most-represented. The non-alkaloid substances were embracive of the same number of unrelated groups including, acids, phenolics, flavonoids and triterpenoids. A wide variety of assays were engaged to ascertain the biological activities of the isolated compounds, notably in regards to cancer and motorneuron-related diseases. There were also attempts made to determine the antimicrobial, anti-inflammatory and antioxidant effects of some of the substances. New information has also emerged on the herbicidal, insecticidal and plant growth regulatory effects of selected alkaloid principles. Coupled to the biological screening measures were in instances probes made to establish the molecular basis to some of the activities, particularly in relation to cancer and Parkinsonʹs disease.


1993 ◽  
Vol 36 (17) ◽  
pp. 2575-2577 ◽  
Author(s):  
Kong Teck Chong ◽  
Mary J. Ruwart ◽  
Roger R. Hinshaw ◽  
Karen F. Wilkinson ◽  
Bob D. Rush ◽  
...  

In pharmaceutical research, traditional drug discovery process is time consuming and expensive, where several compounds are experimentally tested for their biological activities. Series of lab experiments are conducted to analyze newly synthesized drug’s pharmaceutical activities and its biological effects on human. With every new drug discovery, the required clinical properties can be determined using machine learning models and this greatly reduces the experimental cost. This paper explores parametric and non-parametric machine learning models to classify administration properties of drugs and its toxicity. The multinomial classification of drugs was based on their physicochemical and ADMET properties. Balanced data samples were drawn from chEMBL and was pre-processed. Features were reduced using Recursive Feature Elimination and the attributes were ranked based on their importance to reduce highly correlated attributes. The performance of parametric and non-parametric machine learning models was analyzed on cheminformatic data that includes physiochemical, biological and pharmaceutical properties of the drug molecules. Selecting the potent drug candidate along with its administration properties greatly reduces wet lab experimental time and cost. Multiclass classification can be determined efficiently using non-parametric machine learning model. Optimal feature engineering, tuning hyperparameters and adopting hybrid algorithms would result in more accurate predictions in future for cheminformatics data.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Sun Joo Kim ◽  
Heung Chan Oh ◽  
Youn-Chul Kim ◽  
Gil-Saeng Jeong ◽  
Sangkyu Lee

Bakuchicin is a furanocoumarin isolated fromPsoralea corylifoliaand shows several biological activities. Although there have been studies on the biological effects of bakuchicin, its modulation potency of CYP activities has not been previously investigated. Here, we investigated the inhibitory effects of bakuchicin on the activities of CYP isoforms by using a cocktail of probe substrates in pooled human liver microsomes (HLMs) and human recombinantcDNA-expressedCYP. Bakuchicin strongly inhibited CYP1A-mediated phenacetinO-deethylation with an IC50value of 0.43 μM in HLMs. It was confirmed by human recombinantcDNA-expressedCYP1A1 and CYP1A2 with aKivalue of 0.11 μM and 0.32 μM, respectively. A Lineweaver-Burk plot indicated that the inhibition mechanism of bakuchicin was competitive inhibition. Overall, this is the first study to investigate the potential CYP1A1 and CYP1A2 inhibition associated with bakuchicin and to report its competitive inhibitory effects on HLMs.


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