Tannic Acid Groups Research Articles

Tannic acid protects neuroblastoma cells against hydrogen peroxide – triggered oxidative stress by suppressing oxidative stress and apoptosis

Recent investigations indicate that tannic acid is associated with a decrease in oxidative damage. Growing evidence supports the protective effects of tannic acid on the central nervous system (CNS). However, uncertainties persist regarding its influence on hydrogen peroxide (H2O2)-triggered oxidative impairment in nerve cells and its interaction with apoptosis. Hence, the objective of this work was to examine the neuroprotective impact of tannic acid on SH-SY5Y cell impairment following H2O2-induced oxidative stress, particularly concerning apoptotic pathways. The control group received no treatment, while the H2O2 group underwent treatment with 0.5 mM H2O2 for a duration of 24 h. The tannic acid group received treatment with different concentrations of tannic acid for a duration of 24 h. Meanwhile, the tannic acid + H2O2 group underwent pre-treatment with tannic acid for one hour and was subsequently subjected to 0.5 mM H2O2 for one day. Within the tannic acid + H2O2 group, the cell viability in SH-SY5Y cells was notably enhanced by tannic acid at concentrations of 2.5, 5, and 10 μM. It also resulted in a considerable rise in TAS (Total Antioxidant Status) levels and a concurrent decline in TOS (Total Oxidant Status) levels, serving as indicators of reduced oxidative stress. Additionally, tannic acid treatment resulted in decreased levels of apoptotic markers (Bax, cleaved PARP, and cleaved caspase 3) and oxidative DNA damage marker (8-oxo-dG), while increasing the anti-apoptotic marker Bcl-2. The findings from flow cytometry also revealed a significant reduction in the apoptosis rate following pretreatment with tannic acid. In summary, tannic acid demonstrates protective effects on SH-SY5Y cells in the face of H2O2-triggered oxidative damage by suppressing both oxidative stress and apoptosis. Nevertheless, additional research is warranted to assess the neuroprotective potential of tannic acid.

Investigating the in vitro antibacterial efficacy of composite bone cement incorporating natural product-based monomers and gentamicin

ObjectiveThe objective of this study is to investigate the impact of four natural product extracts, namely, aloe-emodin, quercetin, curcumin, and tannic acid, on the in vitro bacteriostatic properties and biocompatibility of gentamicin-loaded bone cement and to establish an experimental groundwork supporting the clinical utility of antibiotic-loaded bone cements (ALBC).MethodsBased on the components, the bone cement samples were categorized as follows: the gentamicin combined with aloe-emodin group, the gentamicin combined with quercetin group, the gentamicin combined with curcumin group, the gentamicin combined with tannic acid group, the gentamicin group, the aloe-emodin group, the quercetin group, the curcumin group, and the tannic acid group. Using the disk diffusion test, we investigated the antibacterial properties of the bone cement material against Staphylococcus aureus (n = 4). We tested cell toxicity and proliferation using the cell counting kit-8 (CCK-8) and examined the biocompatibility of bone cement materials.ResultsThe combination of gentamicin with the four natural product extracts resulted in significantly larger diameters of inhibition zones compared to gentamicin alone, and the difference was statistically significant (P < 0.05). Except for the groups containing tannic acid, cells in all other groups showed good proliferation across varying time intervals without displaying significant cytotoxicity (P < 0.05).ConclusionIn this study, aloe-emodin, quercetin, curcumin, and tannic acid were capable of enhancing the in vitro antibacterial performance of gentamicin-loaded bone cement against S. aureus. While the groups containing tannic acid displayed moderate cytotoxicity in in vitro cell culture, all other groups showed no discernible cytotoxic effects.

Evaluating the effects of tannic acid on rabbit growth performance, digestibility, antioxidant status, intestinal morphology and caecal fermentation and microbiota.

The objective of this study was to assess the effects of dietary supplementation with tannic acid (TA) on the growth performance, digestibility, antioxidant status, intestinal morphology and the caecal fermentation and microbiota in rabbits. A total number of 120 Ira rabbits (30 days of age) were randomly allotted to four dietary treatment groups: TA 0 (control), TA 0.75, TA 1.5 and TA 3, administered basal diets with 0, 0.75, 1.5 and 3 g TA/kg of feed for 28 days. Compared to the control group, dietary 3 g TA/kg inclusion decreased the average daily feed intake (p < 0.05). No significant differences were found in the digestibility among the groups (p > 0.05). Serum total antioxidant capacity was significantly higher in the 3 g/kg TA group than in the other groups (p < 0.05). There was a significant increase in the concentration of propionic acid and butyric acid in the 3 g/kg TA group. The addition of TA had no effect on villus height and crypt depth of small intestine (p > 0.05). The 16S rRNA high-throughput sequencing results showed that at the phylum level, dietary 3 g/kg TA increased the abundance of Bacteroidetes in the caecum of rabbits (p < 0.05). Based on the results, dietary TA is effective in antioxidant capacity of rabbits, improving caecal fermentation and optimizing the caecal microflora. However, the appropriate dosage supplementation of TA in rabbits needs further research.

The effect of tannic acid on renal renin-angiotensin signaling pathway in a model of unilateral ureteral obstruction in male Wistar rats.

The purpose of current study was to elucidate polyphenol tannic acid effect on renal function and activity of the renin-angiotensin system after unilateral ureteral obstruction (UUO). Male Wistar rats were divided into three groups of six randomly: 1) Sham, 2) UUO, and 3) UUO + Tannic acid. Rats in the UUO and UUO + Tannic acid groups experienced unilateral ureteral obstruction. In the Sham group, the abdominal cavity was exposed without UUO induction. In the UUO + Tannic acid group, animals received tannic acid (20mg/kg) intraperitoneally, 6 and 12h after clamping the left ureter and 6 and 12h after the right nephrectomy. Blood samples were taken to measure blood urea nitrogen (BUN) and creatinine levels. Kidney tissue samples were obtained for assessment of oxidative stress, inflammatory indices and the levels of renin-angiotensin system components. Tannic acid administration significantly improved UUO-induced kidney dysfunction (serum BUN: 66.42 ± 14.414mg/dl, p < 0.05; serum creatinine: 1.67 ± 0.258mg/dl, p < 0.05), oxidative stress (MDA level: 95.29 ± 37.35µmol/g tissue, p < 0.05; SOD activity: 59.82 ± 13.41 U/g protein, p < 0.01) and inflammation (renal TNF-α: 57.05 ± 15.653pg/g tissue, p < 0.05; renal IL-6: 117.015 ± 24.076pg/g tissue, p < 0.001). The treatment caused a reduction in the amount of renal angiotensinogen, renin and ACE genes expression compared to the UUO group (Angiotensinogen: 8.9 ± onefold, p < 0.05, Renin: 6.5 ± 1.14 fold, p < 0.05, ACE: 4.9 ± 0.64 fold, p < 0.05). Angiotensin II type 1 receptor protein levels decreased in the tannic acid-treated rats in comparison with the UUO group (0.61 ± 0.136, p < 0.05). According to the result of the current study, tannic acid considerably attenuated the complications of unilateral ureteral obstruction through renin-angiotensin system modulation. Trial registration: IR.TUMS.MEDICINE.REC.1400.802.

Supplementation with Antimicrobial Peptides or a Tannic Acid Can Effectively Replace the Pharmacological Effects of Zinc Oxide in the Early Stages of Weaning Piglets.

Zinc oxide (ZnO) harms the environment and can potentially increase the number of drug-resistant bacteria. Therefore, there is an urgent need to find safe and effective alternatives to improve gut health and reduce the incidence of diarrhea in weaned piglets. This study conducted an antibacterial test of ZnO, antibacterial peptides (AMPs), and tannic acid (TA) in vitro. Thirty piglets were randomly allotted to one of the following three dietary treatments: ZnO (2000 mg/kg ZnO diet), AMPs (700 mg/kg AMPs diet), and TA (1000 mg/kg TA diet). The results showed that the minimum inhibitory concentrations of ZnO and TA against Escherichia coli and Salmonella were lower than those of AMPs, and the minimum inhibitory concentrations of ZnO, AMPs, and TA against Staphylococcus aureus were the same. Compared to ZnO, AMPs increased the digestibility of dry, organic matter and the crude fat. Additionally, TA significantly (p < 0.05) increased the digestibility of dry and organic matter. On experimental day 14, the plasma interleukin-6 (IL-6) content of piglets supplemented with AMPs and TA was increased significantly (p < 0.05). On experimental day 28, alanine aminotransferase activity in the plasma of weaned piglets in the ZnO and TA groups was significantly (p < 0.05) higher than in piglets in the AMPs group. The levels of plasma IL-6 and immunoglobulin M (IgM) were significantly higher (p < 0.05) in the ZnO and AMPs groups than in the TA group. On experimental days 14 and 28, no significant differences were observed in the antioxidant capacity among the three experimental groups. Intestinal microbial diversity analysis showed that the Chao1 and ACE indices of piglets in the AMPs group were significantly higher (p < 0.05) than those in the ZnO and TA groups. At the genus level, the relative abundance of Treponema_2 was higher in the feces of piglets fed a diet supplemented with TA than in those fed diet supplemented with ZnO (p < 0.05). The relative abundance of Lachnospiraceae was higher in the feces of piglets fed a diet supplemented with AMPs than in those fed diet supplemented with ZnO or TA. Overall, AMPs and TA could be added to feed as substitutes for ZnO to reduce diarrhea, improve nutrient digestibility and immunity, and increase the abundance of beneficial intestinal bacteria in weaned piglets.

Beneficial effects of tannic acid on comorbid anxiety in cecal ligation and puncture-induced sepsis in rats and potential underlying mechanisms.

Sepsis-associated encephalopathy (SAE), a neurological dysfunction caused by sepsis, is the most common complication among septic ICU patients. Given the major role of inflammation in the pathophysiology of sepsis-induced anxiety, an extreme and early manifestation of SAE, the present study examined whether tannic acid, as an anti-inflammatory agent, has anxiolytic effects in cecal ligation and puncture (CLP)-induced sepsis. Forty male Wistar rats were assigned to four groups: (1) sham; (2) sham + tannic acid; (3) sepsis and (4) sepsis + tannic acid. Sepsis was induced by cecal ligation and puncture model. Animals in the sham + tannic acid and sepsis + tannic acid groups received tannic acid (20mg/kg, i.p.), 6, 12, and 18h after the sepsis induction. Twenty-four hours after the sepsis induction, systolic blood pressure and sepsis score were assessed. Anxiety-related behaviors were evaluated using elevated plus-maze and dark-light transition tests. Moreover, inflammatory markers (TNF-α and IL-6) and oxidative stress parameters (MDA and SOD) were measured in the brain tissue while protein levels (GABAA receptors and IL-1β) were assessed in the hippocampus. Administration of tannic acid significantly improved sepsis score and hypotension induced by sepsis. Anxiety-related behaviors showed a significant decrease in the sepsis + tannic acid group compared to the sepsis group. Tannic acid caused a significant decrease in the brain inflammatory markers and a remarkable improvement in the brain oxidative status compared to the septic rats. Tannic acid prevented animals from decreasing GABAA receptors and increasing IL-1β protein levels in the hippocampus compared to the sepsis group. This study indicated that tannic acid mitigated anxiety-related behaviors through decreasing inflammation and oxidative stress and positively modifying IL-1β/GABAA receptor pathway. Therefore, tannic acid shows promise as an efficacious treatment for comorbid anxiety in septic patients.

Dietary Galla Chinensis tannic acid supplementation in the diets improves growth performance, immune function and liver health status of broiler chicken.

This experiment was conducted to investigate the effects of Galla Chinensis tannic acid (TA) on growth performance, immune function, and liver health status in broilers. A total of 288 1-day-old Arbor Acres broiler chickens were randomly divided into two groups in a 42-days study. The two groups were a basal diet (CON group) and a basal diet supplemented with 300 mg/kg Galla Chinensis tannic acid (TA group). The results showed that the TA group had significantly decreased feed-to-gain ratio (F/G) throughout the experiment (P < 0.05). The levels of total protein, albumin, low density lipoprotein, high density lipoprotein, urea, total cholesterol, and glucose in the TA group were significantly higher than in the CON group (P < 0.05). In addition, the serum immunoglobulin G, immunoglobulin M, and complements (C3, C4) levels in the TA group were significantly higher than those in the CON group (P < 0.05). Compared with the CON group, the hepatic interleukin-6, interleukin-18, NLRs family pyrin domain containing 3 (NLRP3), caspase-1, and caspase-3 in the TA group were significantly decreased (P < 0.05). Besides, TA group had significantly lower mRNA expression levels of toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), nuclear factor-kappa B (NF-κB), and NLRP3 in liver (P < 0.05). The TA group had significantly higher the mRNA expression levels of Bcl-2 than CON group in liver (P < 0.05). Moreover, TA group tended to decrease Bax/Bcl-2 ratio in liver (P < 0.10). To sum up, dietary supplemented with microencapsulated TA from Galla Chinensis had beneficial effects on growth performance, immune function, and liver health status in broilers. The protective role of TA from Galla Chinensis in liver health of broilers might be related to the inhibition of hepatic apoptosis and pyroptosis via inactivation of TLR4/MyD88/NF-κB signaling pathway.

Engineering tannic acid-polyethyleneimine multilayer-decorated melamine sponge for highly efficient Pb(II) adsorption

Melamine sponge (MS) with open three-dimensional porous structure is regarded to be an ideal substrate to prepare monolithic adsorbents for heavy metal ions removal. However, most of the existing surface modification strategies of MS are still difficult to achieve a satisfactory adsorption ability for Pb(II). In this study, tannic acid (TA) and polyethyleneimine (PEI) were alternatively deposited on the framework of MS via layer-by-layer covalent assembly between polyphenols of TA and amine groups of PEI. The morphology, molecular structure, and overall properties of the obtained multilayer-decorated MS materials (PEI-TA)n-MS were characterized using SEM, XPS, FT-IR, and TGA. (PEI-TA)2-MS was demonstrated to be extremely stable and exhibited excellent adsorption behavior for Pb(II). The maximum Pb(II) adsorption capacity reached 257.4 mg/g at pH value of 5.0 and initial Pb(II) concentration of 200 mg/L. It is better than those of previous reported PEI-based adsorbents under similar conditions. The kinetic and isotherm data revealed that such process is exothermic, and well fits the Langmuir isotherm and the pseudo-second-order kinetic models. The present PEI-TA-based layer-by-layer assembly strategy may offer new prospects for the versatile design of other monolithic adsorbent materials.

Tannic acid reduced apparent protein digestibility and induced oxidative stress and inflammatory response without altering growth performance and ruminal microbiota diversity of Xiangdong black goats.

The present study was performed to evaluate the impacts of tannic acid (TA) supplementation at different levels on the growth performance, physiological, oxidative and immunological metrics, and ruminal microflora of Xiangdong black goats. Twenty-four goats were randomly assigned to four dietary treatments: the control (CON, basal diet), the low-dose TA group [TAL, 0.3 % of dry matter (DM)], the mid-dose TA group (TAM, 0.6 % of DM), and the high-dose TA group (TAH, 0.9 % of DM). Results showed that the growth performance was unaffected (P > 0.05) by adding TA, whilst the 0.3 % and 0.6 % TA supplementation significantly decreased (P < 0.05) the apparent digestibility of crude protein (CP) and ruminal NH3-N concentration, and raised (P < 0.05) the level of total volatile fatty acid (TVFA) in rumen. The increments of alanine aminotransferase (ALT), triglyceride (TG), cortisol (CORT), total antioxidant capacity (T-AOC), interleukin (IL)-1β, IL-6, and serumamyloid A (SAA), and decrements of globulin (GLB), immunoglobulin G (IgG), cholinesterase (CHE), glutathione reductase (GR), creatinine (CRE), growth hormone (GH), high-density lipoprotein cholesterol (HDLC), and insulin-like growth factor 1 (IGF-1) to different extents by TA addition were observed. Although the Alpha and Beta diversity of rumen bacterial community remained unchanged by supplementing TA, the relative abundance of the predominant genus Prevotella_1 was significantly enriched (P < 0.05) in TAL. It could hence be concluded that the TA supplementation in the present trial generally decreased CP digestion and caused oxidative stress and inflammatory response without influencing growth performance and ruminal microbiota diversity. More research is needed to explore the premium dosage and mechanisms of effects for TA addition in the diet of goats.

Gallnut Tannic Acid Exerts Anti-stress Effects on Stress-Induced Inflammatory Response, Dysbiotic Gut Microbiota, and Alterations of Serum Metabolic Profile in Beagle Dogs.

Stress exposure is a potential threat to humans who live or work in extreme environments, often leading to oxidative stress, inflammatory response, intestinal dysbiosis, and metabolic disorders. Gallnut tannic acid (TA), a naturally occurring polyphenolic compound, has become a compelling source due to its favorable anti-diarrheal, anti-oxidative, anti-inflammatory, and anti-microbial activities. Thus, this study aimed to evaluate the anti-stress effects of gallnut TA on the stress-induced inflammatory response, dysbiotic gut microbiota, and alterations of serum metabolic profile using beagle models. A total of 13 beagle dogs were randomly divided into the stress (ST) and ST + TA groups. Dietary supplementation with TA at 2.5 g/kg was individually fed to each dog in the ST + TA group for 14 consecutive days. On day 7, all dogs were transported for 3 h from a stressful environment (days 1–7) to a livable site (days 8–14). In our results, TA relieved environmental stress-induced diarrheal symptoms in dogs and were shown to protect from myocardial injury and help improve immunity by serum biochemistry and hematology analysis. Also, TA inhibited the secretion of serum hormones [cortisol (COR), glucocorticoid (GC), and adrenocorticotropic hormone (ACTH)] and the expression of heat shock protein (HSP) 70 to protect dogs from stress-induced injury, thereby relieving oxidative stress and inflammatory response. Fecal 16S rRNA gene sequencing revealed that TA stimulated the growth of beneficial bacteria (Allobaculum, Dubosiella, Coriobacteriaceae_UCG-002, and Faecalibaculum) and suppressed the growth of pathogenic bacteria (Escherichia-Shigella and Streptococcus), thereby increasing fecal butyrate levels. Serum metabolomics further showed that phytosphingosine, indoleacetic acid, arachidonic acid, and biotin, related to the metabolism of sphingolipid, tryptophan, arachidonic acid, and biotin, respectively, could serve as potential biomarkers of stress exposure. Furthermore, Spearman’s correlation analysis showed strong relationships between the four potential serum biomarkers and differential bacteria. Overall, gallnut TA may be a potential prebiotic for the prevention and treatment of stress-induced metabolic disorders by targeting intestinal microbiota.

The Effects of Polyphenol, Tannic Acid, or Tannic Acid in Combination with Pamidronate on Human Osteoblast Cell Line Metabolism.

Background: This study investigates the effect of tannic acid (TA) combined with pamidronate (PAM) on a human osteoblast cell line. Methods: EC50 for TA, PAM, and different combination ratios of TA and PAM (25:75, 50:50, 75:25) were measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The combination index value was utilized to analyze the degree of drug interaction, while trypan blue assay was applied to analyze the cells proliferation effect. The mineralization and detection of bone BSP and Osx genes were determined via histochemical staining and PCR test, respectively. Results: The EC50 of osteoblasts treated with TA and a 75:25 ratio of TA and PAM were more potent with lower EC50 at 0.56 µg/mL and 0.48 µg/mL, respectively. The combination of TA and PAM (75:25) was shown to have synergistic interaction. On Day 7, both TA and PAM groups showed significantly increased proliferation compared with control and combination groups. On Day 7, both the TA and combination-treated groups demonstrated a higher production of calcium deposits than the control and PAM-treated groups. Moreover, on Day 7, the combination-treated group showed a significantly higher expression of BSP and Osx genes than both the TA and PAM groups. Conclusion: Combination treatment of TA and PAM at 75:25 ameliorated the highest enhancement of osteoblast proliferation and mineralization as well as caused a high expression of BSP and Osx genes.

IN VITRO STUDIES ON THE PROTECTIVE EFFECT OF TANNIC ACID OF U87 CELLS INDUCED BY BETA-AMYLOID

This study shows that tannic acid is an Alzheimer's disease (AD) model cell line on amyloid-beta (Aβ)-induced U87 (human astrocytoma cell line) in β-amyloid (Aβ)-induced in vitro Alzheimer's Disease (AD) model. We aimed to investigate the effects of antioxidants.In the study; Three groups were formed as the control group, the Aβ group, and the Aβ + tannic acid group obtained by adding tannic acid to the Aβ group. Firstly, the cytotoxic potential of TA in U87 cells was investigated by the colorimetric MTT (3-4,5-dimethyl-thiazolyl-2,5 diphenyltetrazolium bromide) test. To determine the antioxidant status in the cell line treated with Thymoquinone, to examine the effects of superoxide dismutase (SOD), catalase (CAT) activities, total oxidant status (TOS), and total antioxidant status (TAS) were measured by the ELISA method. When compared to the control group, the SOD, CAT, and TOS levels were significantly decreased in the U87 cell line exposed to Aβ; TAS levels were found to increase significantly. However, the application of tannic acid to the Aβ-U87 cell line significantly increased SOD, CAT, and TAS levels; It was found that it decreased the TOS level. In in vitro experiments, we determined that tannic acid has a protective effect by increasing antioxidant parameters in the amyloid beta-induced cell line.

Tannic acid extracted from gallnut prevents post-weaning diarrhea and improves intestinal health of weaned piglets.

This experiment was conducted to evaluate the effects of different levels of tannic acid (TA) on growth performance, diarrhea rate, nutrient digestibility and intestinal health in weaned piglets. A total of 180 weaned piglets (Duroc × Landrace × Yorkshire, 24 d of age, initial average BW = 7.77 ± 0.17 kg) were allotted to 5 groups (6 pigs/pen and 6 replicates/group) in a randomized complete block design according to their gender and body weight. Piglets were fed a basal diet, or the basal diet supplemented with 0.05%, 0.1%, 0.2% or 0.4% TA for 28 d. The supplementary levels of TA in the diets were obtained by adding tannalbin containing 51% TA and 40.17% protein. The results showed that, compared with the CON group, dietary TA did not affect ADFI, ADG or F:G, and linearly reduced (P < 0.01) the diarrhea rate and diarrhea index of piglets. There were no significant effects on apparent total tract digestibility (ATTD) in the 0.05%, 0.1% and 0.2% TA groups, while negative effects (P < 0.05) on apparent digestibility of crude protein and gross energy were observed in the 0.4% TA group. In addition, the nutrient digestibility of dry matter, crude protein and gross energy linearly decreased (P < 0.01) with the increase of TA dosage. Supplementation of TA increased (P < 0.05) the villus height of the duodenum and jejunum, as well as increased (P < 0.05) catalase (CAT) activity in serum. Dietary TA improved (P < 0.05) the Bacillus counts in cecal digesta. Further, TA significantly improved (P < 0.05) Bacillus counts and reduced (P < 0.05) the Escherichia coli counts in colonic digesta. The concentration of acetic acid, propionic acid, butyric acid and isovaleric acid in cecal digesta were significantly increased (P < 0.05). The mRNA expression level of zonula occludens-1 (ZO-1), zonula occludens-2 (ZO-2), and claudin-2 (CLDN-2) in the jejunum were greater (P < 0.05) in TA supplemented groups. The study showed that, compared to the control, TA prevented post-weaning diarrhea and improved intestinal health of weaned piglets, and the appropriate level of TA supplementation would be from 0.1% to 0.2%.

Study on the Mechanism of Protective Effect of Tannic Acid on the Myocardial Hypertrophy Induced By Pressure Overload

Cardiac hypertrophy was a compensatory response to normal cardiac pressure overload, which eventually leads to heart failure. Therefore, the research of new drugs for the treatment of cardiac hypertrophy was one of the hotspots. In this paper, we explore the protective effect of tannic acid on myocardial hypertrophy and its potential mechanism. The rat model of cardiac hypertrophy was established by abdominal aortic banding. According to the random control principle, the rats treated with sham operation were used as the control group. Abdominal aortic banding rats were treated with tannic acid (20 and 40 mg/kg) or captopril and divided into low dose tannic acid group, high dose tannic acid group, and captopril group. The hemodynamic parameters of rats in each group were detected respectively, and then the related proteins and tissues were detected after the rats were killed. The results showed that the cardiac morphology and pathology of abdominal aortic banding rats treated with tannic acid were significantly improved, myocardial hypertrophy and apoptosis were decreased and the overexpression of Angiotensin II type 1 receptor and Angiotensin II type 2 receptor was decreased. In addition, the messenger Ribonucleic acid expression of extracellular signal regulated kinase 1/2, transforming growth factor-β and matrix metalloproteinase-9 decreased. At the same time, tannic acid treatment decreased the activity and content of malondialdehyde and endothelin-1, and increased the content of superoxide dismutase, catalase, glutathione peroxidase, nitric oxide, and endothelial nitric oxide synthase. In addition, tannic acid downregulated the expression of tumor necrosis factor-α, interleukin-1 β, B-cell lymphoma-2 associated X protein and cysteine-dependent aspartate specific proteases-3 and up-regulated the expression of B-cell lymphoma-2. Tannic acid treatment can improve abdominal aortic banding induced cardiac hypertrophy effectively. Its cardioprotective effect is partly attributed to the reduction of myocardial oxidative stress, inhibition of inflammation, inhibition of fibrosis, reduction of apoptosis, increase of nitric oxide level, decrease of endothelin-1 level, and down-regulation of Angiotensin II type 1 receptor.

The Mechanism Underlying the Protective Effects of Tannic Acid Against Isoproterenol-Induced Myocardial Fibrosis in Mice.

Tannic acid (TA) belongs to a class of complex water-soluble polyphenolic derivatives that show anticarcinogenic, antiinflammatory, antioxidant, and scavenging activities. Here, we investigate the protective effects of TA against isoproterenol (ISO)-induced myocardial fibrosis (MF) in mice. Mice received TA and ISO dosing and were sacrificed 48 h later. The activities of creatine kinase (CK), creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and mitochondria enzymes were measured. Cardiac histopathology was done using H&E, Sirius red, and Masson’s Trichrome staining. Immunohistochemical staining was applied to indicate changes in B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), and basic fibroblast growth factor (bFGF) protein expressions in cardiac tissue. RT-PCR was used to measure the expression of atrial and brain natriuretic peptides (ANP and BNP, respectively), c-fos, and c-jun. Western blotting was used to measure the expression of nuclear factor-κB (NF-κB) p65, phosphorylated NF-κB p65), toll-like receptor 4 (TLR4), p38, phosphorylated p38, Bax, Bcl-2, and caspase-3. Compared to the ISO group, the TA group had reduced levels of TLR4, p38, p-p38, NF-κB (p65), p-NF-κB (p-p65), caspase-3, Bax, and Bcl-2, as well as CK, CK-MB, and LDH. These results indicate that TA protects against ISO-induced MF, possibly through its ability to suppress the TLR4-mediated NF-κB signaling pathway.

Tannic acid as a co-former in co-amorphous systems: Enhancing their physical stability, solubility and dissolution behavior.

Co-amorphous systems have been increasingly investigated to improve the solubility and dissolution rate of poorly soluble drugs. Considering the ability of tannic acid (TA), a polyphenolic compound, to form hydrogen bonds with compounds that contain carbonyl groups, we hypothesized that tannic acid will also be effective in stabilizing amorphous form of drugs in co-amorphous systems. Co-amorphization by TA of two poorly soluble model drugs, carbamazepine (CBZ) and indomethacin (IND) was investigated. Tannic acid facilitated the amorphization of studied drugs and successful co-amorphous systems were obtained as proved by powder X-Ray diffraction (PXRD). Differential scanning calorimetry (DSC) confirmed the homogeneous structure as indicated by the existence of a single Tg for each co-amorphous product. The expected molecular interactions between phenolic groups in TA and carbonyl groups in the studied drugs (CBZ and IND) were confirmed by analyzing their infrared spectra. Drug-TA co-amorphous formulations showed an enhanced equilibrium solubility over the individual drugs. Powder dissolution test under sink conditions showed improved dissolution profiles of drug-TA co-amorphous formulations compared to the corresponding crystalline drugs and physical mixtures. Tannic acid also showed a superior stabilizing effect. CBZ-TA co-amorphous system was physically stable at dry conditions (up to 6months at 40°C), under 60% relative humidity (up to one month at 20°C), and in solution (after 48h of solubility measurements), as revealed by PXRD examination of the remaining solid after solubility measurement. However, IND-TA co-amorphous formulation remained stable at dry conditions up to 6months at 4°C and up to one month at 60% relative humidity at 20°C. These findings demonstrate the potential of tannic acid as a promising co-former in co-amorphous systems of poorly soluble drugs.

Potential anti-inflammatory effect of Madi-Ryuk and its active ingredient tannic acid on allergic rhinitis

Madi-Ryuk (MDR) is a traditional Korean medicine and it has been widely used in Korea to treat arthritis and we previously reported the anti-allergic inflammatory effect of MDR in vitro model. However, therapeutic evidence of MDR on in vivo model of allergic inflammatory reaction has not yet been demonstrated. The research purpose was to investigate the efficacy of MDR and its active ingredient tannic acid (TA) in ovalbumin (OVA)-induced AR mice model. OVA-challenged AR mice orally medicated MDR or its active ingredient TA daily for ten days. In mice having a AR, MDR and TA prominently diminished number of rubs and levels of histamine, IgE, thymic stromal lymphopoietin, interleukin (IL)-1β, IL-4, IL-5, IL-13, IL-33, and tumor necrosis factor-α. In addition, protein expression levels and activities of caspase-1 were declined by oral medication of MDR and TA. Decline in levels of macrophage inflammatory protein-2 and intercellular adhesion molecules-1 and reduction in penetrations of inflammatory cells into inflamed tissue were also noted in MDR and TA groups. Taken together, identification of MDR effect in preclinical models suggests that MDR may be a therapeutic drug for the treatment and prevention of AR.

Tannic Acid Accelerates Cutaneous Wound Healing in Rats Via Activation of the ERK 1/2 Signaling Pathways.

Objective: This study was aimed to evaluate the effect of tannic acid (TA), a natural plant polyphenol astringent, on wound healing in vitro and in vivo, and to elucidate the underlying molecular signaling pathway in the wound healing. Approach: Cutaneous skin wounds were created in rats and then treated until closure with purified TA, serum or tissue samples were collected to test the concentration of factors by enzyme-linked immunosorbent assay (ELISA), and the expression in gene or protein was measured by quantitative real-time polymerase chain reaction or Western blot. We explored the cell-/dose-specific responses of TA (0.1-0.4 μg/mL) on proliferation and gene and protein expression of fibroblast NIH 3T3 cells. Results: The wounds on rats treated by TA got healed faster than those in the untreated group. The histopathology study showed that TA accelerated re-epithelialization and increase in hair follicles could be detected. The levels of growth factors including basic fibroblast growth factor (bFGF), transforming growth factor-beta, and vascular endothelial growth factor in TA-treated groups were all increased, and the content of interleukin-1 (IL-1) and IL-6 was decreased significantly when compared with that of the untreated group. The NIH 3T3 cells grow faster in 6 h at concentration of 0.1 μg/mL, and the expression of bFGF in gene and protein was increased significantly in the 0.1 μg/mL TA group. Further study revealed that the protein levels of bFGF, extracellular signal regulated kinase (Erk) 1/2, and P-Erk 1/2 in Erk 1/2 pathway were increased after TA treatment. Innovation: The role of TA in wound healing efficacy is unclear; this study, therefore, assesses the effects of TA on wound healing in different periods and the underlying molecular mechanisms. Conclusion: These results suggested that TA could accelerate wound healing through modulation of inflammatory cytokines and growth factors and activate Erk 1/2 pathway. In conclusion, TA may be a potential agent in promoting wound healing.

Multilayer Assembly of Tannic Acid and an Amphiphilic Copolymer Poloxamer 188 on Planar Substrates toward Multifunctional Surfaces with Discrete Microdome-Shaped Features.

Tannic acid (TA) is a natural polyphenol compound with a broad spectrum of biological activities, the most notable of which being antioxidation. Poloxamer 188 (P188), a synthetic triblock copolymer of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide), is amphiphilic in nature and best known for its ability to seal structurally damaged cellular membranes. The integration of both substances onto planar substrates could bring a new option for multifunctional coatings that are advantageous for implantable biomedical devices. Here, we demonstrate the feasibility of multilayer assembly of TA/P188 toward such a coating based on hydrogen bonding between phenolic hydroxyls of TA and ether groups of P188, and the unique surface feature it generates. The interactions between these two compounds were studied both in solution and in substrate-supported layer-by-layer assembly. The multilayer assembly process exhibits an exponential growth pattern as characterized by UV-vis spectrophotometry and quartz crystal microbalance with dissipation. Morphologically unique, microdome-shaped surface features emerge and evolve with the number of layers assembled. Such features bring a reservoir function to this coating, as demonstrated by the loading of hydrophobic nile red dye. Furthermore, the presence of TA in the multilayers was revealed by silver nitrate staining, and its antioxidation activity was demonstrated through a 2,2-diphenyl-1-picryl-hydrazyl free-radical scavenging assay.

Cross-linked graphene oxide membrane having high ion selectivity and antibacterial activity prepared using tannic acid-functionalized graphene oxide and polyethyleneimine

A covalently cross-linked graphene oxide (GO) membrane was prepared by a facile vacuum filtration method followed by a cross-linking process using tannic acid-functionalized GO (TA-GO) and hyperbranched polyethyleneimine (PEI). The TA-GO was prepared by a simple and environmentally friendly method using GO and a renewable plant-based polyphenol, tannic acid (TA), and it was covalently cross-linked by PEI via the reaction between catechol groups in TA and amine groups in PEI to form covalent bonds in a weak alkaline environment producing the cross-linked GO membrane. The cross-linked GO membrane showed excellent dimensional stability and ions separation performance. In particular, the cross-linked GO membrane containing TA showed excellent antibacterial activity against Escherichia coli (E. coli) due to the intrinsic bactericidal properties of the TA moieties. Furthermore, the membrane exhibited higher water flux and rejections toward NaCl and MgSO4 than the commercial nanofiltration (NF) membranes.