Action Of Tannic Acid Research Articles

Biomimetic nanoparticles co-deliver hirudin and lumbrukinase to ameliorate thrombus and inflammation for atherosclerosis therapy

Atherosclerosis (AS) is a progressive inflammatory disease, and thrombosis most probably leads to cardiovascular morbidity and mortality globally. Thrombolytic drugs alone cannot completely prevent thrombotic events, and treatments targeting thrombosis also need to regulate the inflammatory process. Based on the pathological process of AS dynamic development, biomimetic thrombus-targeted nanoparticles HMTL@PM were prepared. Hirudin and lumbrukinase, the effective substances of traditional Chinese medicine, were self-assembled under the action of tannic acid and Mn2+. HMTL@PM dissociated in the weakly acidic microenvironment of atherosclerosis and exhibited an excellent therapeutic effect of alleviating inflammation, dissolving thrombus, anticoagulation, and promoting cholesterol efflux. HMTL@PM effectively regulated the progression of AS and provided a new perspective for the development of drug delivery systems for AS therapy, which owned important research significance for reducing the mortality of cardiovascular and cerebrovascular diseases.

Tannic acid attenuate AKT phosphorylation to inhibit UMUC3 bladder cancer cell proliferation.

Urothelial bladder cancer is rapidly spreading across Western countries, and therapy has shown little-to-moderate effects on bladder cancer. Thus, focusing on curbing cancer incidence has become crucial. The aim of the present study was to investigate the anticancer effects of Tannic acid (TA) in human bladder cancer. UMUC3 bladder cancer cells were treated with different concentrations of TA (0-100µM) and tested for cell viability, colony formation, and apoptosis. The involvement of the phosphoinositide-3 kinase (PI3K)/Akt pathway in the action of TA was examined. TA treatment significantly inhibited the viability and increased percentage of apoptotic cells, thereby decreasing antiapoptotic proteins (BCL2, MCL-1, and BCL-XL) expression, resulting in the Caspase-3 activation. TA treatment decreased stem cell markers expression such as SOX2, OCT4, and NANOG. Additionally, TA treatment significantly reduced the phosphorylation levels of Akt in bladder cancer cells. Our study demonstrates the growth inhibitory effects of TA in bladder cancer cells, and highlights its potential as an anticancer agent for bladder cancer.

Tannic acid elicits selective antitumoral activity in vitro and inhibits cancer cell growth in a preclinical model of glioblastoma multiforme.

Glioblastoma is a devastating tumor affecting the central nervous system with infiltrative capacity, high proliferation rate and chemoresistance. Therefore, it is urgent to find new therapeutic alternatives that improve this prognosis. Herein, we focused on tannic acid (TA) a polyphenol with antioxidant and antiproliferative activities. In this work, the antitumor and antioxidant effects of TA on rat (C6) glioblastoma cells and their cytotoxicity relative to primary astrocyte cultures were evaluated in vitro. Cells were exposed to TA of 6.25 to 75μM for 24, 48 and/or 72h. In addition, colony formation, migration and cell adhesion were analyzed and flow cytometry was used to analyze cell death and cell cycle. Next, the action of TA was evaluated in a preclinical glioblastoma model performed on Wistar rats. In this protocol, the animals were treated with a dose of 50mg/kg/day TA for 15days. Our results demonstrated that TA induced in vitro selective antiglioma activity, not demonstrating cytotoxicity in astrocyte culture. It induced cell death by apoptosis and cell cycle arrest, reducing formation and size of colonies, cell migration/adhesion and showing to be a potential antioxidant. Interestingly, the antiglioma effect was also observed in vivo, as TA decreased tumor volume by 55%, accompanied by an increase in the area of intratumoral necrosis and infiltration of lymphocytes without causing systemic damage. To the best of our knowledge, this is the first study to report TA activity in a GBM preclinical model. Thus, this natural compound is promising as a treatment for glioblastoma.

317 ANTI-HYALURONIDASE ACTION OF ELLAGIC ACID EFFECTIVELY PREVENTS POLYSPERMY THROUGH SUPPRESSION OF THE ACROSOME REACTION INDUCED BY THE SPERM - ZONA INTERACTION DURING PORCINE IN VITRO FERTILIZATION

We previously reported that the anti-hyaluronidase agents oligosaccharide and tannic acid (TA) were efficient probes for promoting the normal fertilization process in terms of an effective decrease in the incidence of polyspermy, not only in cumulus-enclosed but also in denuded oocytes in pigs. It was unclear, however, why the polyspermic penetration into the zona pellucida (ZP) was directly prevented by the anti-hyaluronidase action. The present study was conducted to examine the effects of 3 tannin relatives [TA, gallic acid (GA), and ellagic acid (EA)] on IVF parameters and the acrosome reaction induced by the sperm–ZP interaction. The anti-hyaluronidase and radical-scavenging activities of tannin relatives were measured by the colorimetric and the DPPH methods, respectively. Porcine cumulus–oocyte complexes (COCs) were cultured for 44 h in 0.1 mL of TCM-199 supplemented with 0.6 mM cysteine, 40 mU mL-1 of FSH, 20 mU mL-1 of LH, and 10% porcine follicular fluid. After in vitro maturation (IVM), the COCs were freed from their cumulus cells and inseminated by frozen-thawed ejaculated sperm in modified Tris-buffered medium (IVF medium) containing 0 (control) or 5 �g mL-1 of tannin relatives. After 2 h of co-incubation, the oocytes were gently pipetted to remove loosely bound sperm and stained with Hoechst 33342 to count the number of ZP-bound sperm, or stained with fluorescein isothiocyanate (FITC)-PNA, PI, and 422,6-diamidino-2-phenylindole to evaluate the acrosomal status. At 10 h post-insemination, IVF parameters were examined by lacmoid staining. The data were analyzed by ANOVA and the Tukey-Kramer test. None of the tannin relatives caused a protective proteolytic modification of the ZP matrix or a reduction of the acrosomal proteolytic activity or the number of ZP-bound sperm. There was no difference in the sperm penetration rate even in the presence of tannin relatives (73-82%). However, the incidence of polyspermy was remarkably prevented by TA (32%; 31/98) and EA (21%; 20/94) compared with the control (58%; 58/100; P < 0.05), resulting from their strong anti-hyaluronidase actions, whereas GA without the anti-hyaluronidase action had no effect on the prevention of polyspermy (51%; 43/84). The rate of acrosome reaction induced by the sperm–ZP interaction was decreased by TA (15%; 123/833) and EA (16%; 110/708) compared with the control (25%; 238/939; P < 0.05), and a similar result was found in sperm binding to the pretreated ZP with 500 U of hyaluronidase for 2 h (18%; 351/1959). Interestingly, when sperm were incubated in IVF medium with 10 �g mL-1 of progesterone for 0.5 h to induce a compulsory acrosome reaction instead of the ZP, EA never disturbed the acrosome reaction (23%; 98/424) as control (23%; 102/437), although this reaction was blocked by TA (13%; 57/427) and GA (13%; 50/375), which possessed higher levels of radical-scavenging activity than EA (P < 0.05). These results indicate that the anti-hyaluronidase action of TA and EA effectively prevented polyspermy during porcine IVF as a consequence of suppression of the acrosome reaction functionally induced by the sperm–ZP interaction requiring the hyaluronidase intervention.

Action of tannic acid on consumption and utilisation of food by Ectomyelois ceratoniae zeller (Lepidoptera: Pyralidae)

Tannic acid as 1.5% of an artificial diet extended the larval developmental period of Ectomyelois ceratoniae three times and reduced the development rate by one fourth. The larvae consumed twice as much tannic acid diet as control diet without increasing in weight. They assimilated some tannic acid but eliminated most in the faeces. These results were considered in relation to tannins as allelochemicals in pomegranate fruits.

Coated vesicles are implicated in the post-fusion retrieval of the membrane of rat atrial secretory granules.

Using an in situ tannic acid perfusion technique, this study presents evidence that the removal of membrane components from the rat atrial secretory granule membrane after granule exocytosis is mediated by coated vesicles. When tannic acid is used to arrest the post-fusion stages of granule release, coated pit formation occurs on granule membrane, which, although continuous with the sarcolemma, is easily recognised by the membrane omega profile and the continued presence of the granule core. Tannic acid perfusion, before aldehyde fixation, allows a degree of continued cell function, and granule fusions can persist after tannic acid has reached the cell. This results in an increase in the numbers of fusion profiles and the appearance of coated pits on granule membrane at these sites. The proportion of granules with coats increases with perfusion time, suggesting that endocytotic, as well exocytotic events, may be arrested by the action of tannic acid. Coated vesicles are also involved at earlier stages of the release pathway. In other types of secretory system this is considered to represent recycling of membrane proteins as part of the maturation process of the granule. Although arrested granules exhibiting this clathrin coat could have had the coat prior to fusion, as part of the maturation process, our results show that it is more likely to represent a second stage of membrane protein recycling; the postfusion reclamation of proteins from the sarcolemma. This facet of the tannic acid perfusion procedure suggests a general method for quantifying coated pit formation during secretory granule release.

Pharmacological actions of tannic acid; II. Evaluation of CNS activity in animals.

The effects of tannic acid (TA) on some behavioral tests in animals were investigated. A non-specific depressant action of TA was the most salient finding in the present study since TA reduced locomotor activity, potentiated pentobarbital-induced sleeping-time and induced analgesia in mice. No changes were found on the convulsive threshold test in rats. It is concluded that the reported central depressant effects of some crude extracts from plant material could be due to the presence of tannin-like constituents in the plant.

Tannic Acid and Oxidized Tannic Acid on the Functional State of Rat Intestinal Epithelium

Diets containing tannic acid at the level of 3% of dry matter were fed to rats in order to ascertain the origin of fecal nitrogen and the effect of tannic acid on the intestinal mucosa. At the same time in order to explain the effect of oxidation of tannins, we administered diets containing oxidized tannic acid or tannic acid associated with an antioxidizer (sodium sulfite) at the level of 1% of dry matter. The increased excretion of sialic acid and glucosamine during ingestion of tannic acid indicated that the excess of fecal nitrogen mainly corresponds to the mucus hypersecretion observed by histology. Fecal analysis revealed perturbations in movements of water and ions. The study of the metabolic activity of isolated enterocytes and the activity of some enzymes in a homogenate of these cells showed an inhibition of oxygen consumption and succinic dehydrogenase activity. Addition of reducing agent (sodium sulfite) to the diet had little effect on the action of tannic acid; but previous oxidation of the tannin reduced the effects observed, particularly in the case of fecal nitrogen loss.

Inhibitory Effect of Tea Catechin on the Local Lesion Formation Caused by Tobacco Mosaic Virus

Tea leaf galloyl - catechins, (-) -epicatechin gallate ((-) ECg) and (-) -epigallocatechin gallate ((-) EGCg) inhibited local lesion formation by tobacco mosaic virus (TMV) on Nicotiana glutinosa. In the present report, the amount of catechins necessary for inhibiting TMV infectivity and recovery of the infectivity after catechin removal by gelatin were investigated. When 0.1 and 0.2% (w/v) of (-) ECg were added to TMV solution (ca. 32μg/ml), the inhibition was estimated to be 90 and 99%, respectively. The same concentrations of (-) EGCg inhibited by 98 and 99%, respectively. When a definite concentration of gelatin was added to the mixture of (-) ECg and infected tobacco leaf extract, the number of local lesions increased as the period of incubation was prolonged. The addition of gelatin, however, did not cause any change in the inhibitory activity of (-) EGCg even after aprolonged incubation. The mode of inhibition by catechin of the local lesion formation was discussed in connection with the action of tannic acid.

Internal perfusion of crayfish, giant axons: action of tannic acid, DDT, and TEA.

AbstractCrayfish giant axons remain viable following internal perfusion with a mixture of fluoride and citrate salts. The relative favorability of various internal anions, and the dependence of resting and action potentials on internal cations are both similar to results on internally perfused squid axons. TEA widens the falling phase of the spike only from inside the axon, while DDT is active from either side of the membrane. Records of impedance changes show that effects of TEA and DDT on components of ionic conductances are similar to those found in other axons by voltage clamp measurements.Tannic acid perfused internally at a concentration of the order of 10 μM produces spontaneous activity, and a progressive increase in spike width. After 30 minutes, action potentials are “cardiac” type and are up to several minutes in duration. Records of impedance changes, and data from rapid changes in external ionic concentrations, suggest that the plateau phase of the spike is due to a maintained increase in sodium conductance. Since tannic acid is capable of crosslinking proteins and “rigidifying” protein monolayers, it is suggested that its effects on the axon may be the result of an interference with a conformational change in a membrane protein or protein‐phospholipid complex during excitation.

STUDIES ON EFFECT OF TANNIC ACID ON STREPTOLYSIN-S SUSCEPTIBILITY OF ERYTHROCYTES

There have been several reports on the action of tannic acid upon red blood cells (1, 2). The present paper is concerned with observations indicating that tannic acid acts upon mammalian red blood cells, rendering them resistant to streptolysin-S, an oxygens'able hemolysin of Streptococcus pyogenes (3, 4), in such a manner that the lost susceptibility of the tanned cells can be readily restored by treating them with certain proteins.

The action of tannic acid on model systems formed of constituents of the erythrocyte membrane.

The action of tannic acid on model systems formed of constituents of the erythrocyte membrane.

The action of tannic acid on the erythrocyte membrane.

The action of tannic acid on the erythrocyte membrane.

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