Differential modulation of apoptotic processes by proanthocyanidins as a dietary strategy for delaying chronic pathologies

Instant and Multifunctional Nanofibers Loaded with Proanthocyanidins and Hyaluronic Acid for Skincare Applications

Hyaluronic-acid- and silk-fibroin-based nanofibrous mats loaded with proanthocyanidins and collagen peptides were fabricated as multifunctional facial masks using electrospinning. Their morphology, hygroscopicity and moisture retention, DPPH, ABTS free radical scavenging abilities, and cytocompatibility were investigated. The results showed that the nanofibrous mats were dense and uniform, with an average diameter ranging from 300 to 370 nm. The nanofibrous mats exhibited satisfactory moisture retention, oxidation resistance, biocompatibility, especially excellent DPPH, and ABTS free radical scavenging capacities. DPPH free radical scavenging activity was 90% with 15 mg/L nanofibers, and ABTS free radical scavenging activity was 90% with 0.005 mg/L nanofibers. The nanofibrous mats protected fibroblasts from oxidative stress damage induced by tert-butyl hydroperoxide (t-BHP) and significantly promoted their proliferation. Compared with traditional liquid masks and semi-solid facial masks, the multifunctional nanofibrous mats prepared in this study contained fewer additives, which has significant advantages in terms of safety. The nanofibrous mats were rapidly dissolved within 5 s after being sprayed with water, which facilitated the release and penetration of active ingredients for skincare. Therefore, the multifunctional nanofibrous mats displayed excellent moisture retention, oxidation resistance, and biocompatibility, indicating promising translational potential as facial masks and providing a valuable reference for skincare.

Proanthocyanidins alleviate pentylenetetrazole-induced epileptic seizures in mice via the antioxidant activity

The role of oxidative stress in the initiation and progress of epilepsy is well established. Proanthocyanidins (PACs), a naturally occurring polyphenolic compound, have been reported to possess a broad spectrum of pharmacological and therapeutic properties against oxidative stress. However, the protective effects of proanthocyanidins against epilepsy have not been clarified. In the present study, we used the pentylenetetrazole (PTZ)-induced epilepsy mouse model to explore whether proanthocyanidins could help to reduce oxidative stress and protect against epilepsy. Mice were allocated into four groups (n = 14 per each group): control, PTZ (60 mg/kg, intraperitoneally), PACs + PTZ (200 mg/kg, p.o.) and sodium valproate (VPA) + PTZ (200 mg/kg, p.o.). PTZ injection caused oxidative stress in the hippocampal tissue as represented by the elevated lipid peroxidation and NO synthesis and increased expression of iNOS. Furthermore, depleted levels of anti-oxidants, GSH, GR, GPx, SOD, and CAT also indicate that oxidative stress was induced in mice exposed to PTZ. Additionally, a state of neuroinflammation was recorded following the developed seizures. Moreover, neuronal apoptosis was recorded following the development of epileptic convulsions as confirmed by the elevated Bax and caspase-3 and the decreased Bcl2 protein. Moreover, AChE activity, DA, NE, 5-HT, brain-derived neurotrophic factor levels, and gene expression of Nrf2 have decreased in the hippocampal tissue of PTZ exposed mice. However, pre-treatment of mice with PACs protected against the generation of oxidative stress, apoptosis, and neuroinflammation in the PTZ exposed mice brain as the biomarkers for all these conditions was bought to control levels. In addition, the gene expression of Nrf2 was significantly upregulated following PACs treatment. These results suggest that PACs can ameliorate oxidative stress, neuroinflammation, and neuronal apoptosis by activating the Nrf2 signaling pathway in PTZ induced seizures in mice.

Antiulcer activity of proanthocyanidins is mediated via suppression of oxidative, inflammatory, and apoptotic machineries

Gastric ulcer (GU) is a lesion in the gastric mucosa associated with excessive oxidative damage, inflammatory response, apoptotic events, and irritation which may develop into cancer. However, medications commonly used in GU treatment cannot normalize gastric mucosa, while causing several adverse effects. Proanthocyanidins (PAs) are dietary flavonoids with numerous biological and pharmacological activities. In the current investigation, we studied the potential anti-ulcerative activity of PAs against acidified ethanol (HCl/ethanol)-caused gastric ulceration. Fifty male albino Wistar rats were allocated into five equal groups: control, HCl/ethanol (3 mL/kg), lansoprazole (LPZ, 30 mg/kg) + HCl/ethanol, and PAs (100 and 250 mg/kg) + HCl/ethanol. LPZ and PAs were applied one week before gastric ulcer induction. PAs pretreatment notably reduced gastric mucosal macroscopic and microscopic pathological changes in a dose-dependent manner. Additionally, PAs activated the innate antioxidant molecules including glutathione and its derived antioxidants (glutathione peroxidase and glutathione reductase), along with superoxide dismutase and catalase, while attenuating pro-oxidant formation, including malondialdehyde and nitric oxide. Interestingly, PAs supplementation at a higher dose suppressed gastric inflammatory and apoptotic responses, as demonstrated by the reduced levels of interleukin-1β, interleukin-6, tumor necrosis factor alpha, high-mobility group box 1, cyclooxygenase 2, prostaglandin E2, nuclear factor kappa-B, Bcl-2-associated X protein, and caspase-3, while B cell lymphoma 2 was elevated. Hence, PAs could exhibit antiulcer activity by protecting gastric tissue from the development of oxidative damage, inflammatory responses, and apoptosis events associated with ulceration. PRACTICAL IMPLICATIONS: Gastric ulcer is a lesion in the gastric mucosal layer associated with excessive inflammatory response, apoptotic events, oxidative damage, and irritation, and may develop into cancer with about 5%-10% morbidity rate. However, medications commonly used in GU treatment cannot normalize gastric mucosa, while causing several adverse effects. Therefore, new therapeutic approaches are needed to treat or prevent gastric ulceration. Proanthocyanidins (PAs, condensed tannins) are dietary flavonoids found in abundance in different plant species, including their fruits, bark, and seeds. Due to their potent antioxidative activity, PAs have been applied to prevent or treat oxidative stress-related diseases, including cancer, as well as metabolic, neurodegenerative, cardiovascular, and inflammatory disorders. Here, we examine the potential therapeutic role of proanthocyanidins (PAs) against acidified ethanol-induced gastric ulcer in rats through evaluating oxidative challenge, inflammatory response, apoptotic events, and histopathological changes in the gastric tissue.

Effect of supplementing fava bean (Vicia faba L.) on ulcerative colitis and colonic mucosal DNA content in rats fed a high-sucrose diet

Ulcerative colitis (UC) is an inflammatory bowel disease with high morbidity. Acetic acid-induced damage of colonic mucosa in rats is a commonly used experimental animal model of UC. This research aimed to explore for the first time the ameliorative effect of dietary supplementation with fava bean on the incidence of UC in rats fed with sucrose containing diet. Rats were divided into five groups as follows: G1, control healthy rats; G2, colitic rats; G3, colitic rats fed diets containing 30% sucrose, G4, healthy rats fed diets containing 30% sucrose and G5, colitic rats fed diets containing 30% sucrose supplemented with dried ground fava bean. Colonic injury and inflammation were evaluated through a disturbance of oxidative biomarkers, a significant increase in inflammatory biomarkers and inflammatory cytokines, and histological abnormalities in colonic tissues accompanied by colonic mucosal DNA damage. Colitic rats fed on sucrose containing diet demonstrated additional histological, biochemical, and DNA alterations in colonic mucosa of rats. Dietary supplementation with dried ground fava bean significantly corrected the impaired oxidative and inflammatory biomarker levels and modulated histological features and DNA alterations. Finally, fava bean attenuated the oxidative damage and colonic injury induced by acetic acid, which confirmed its high anti-oxidant and anti-incendiary properties.

Protective effect of procyanidin A-type dimers against H2O2-induced oxidative stress in prostate DU145 cells through the MAPKs signaling pathway

It has been reported that B-type procyanidins can alleviate oxidative damage of prostatic cells, but there has been limited information on the similar role of A-type procyanidins. This study investigated the protective effect of procyanidin A-type dimers from peanut skin against H₂O₂-induced oxidative stress damage in prostate cancer DU145 cells. According to the UPLC-Q-TOF-MS/MS analysis and comparison with standards, the fourth fraction of peanut skin procyanidin (PSP-4) was identified as procyanidin A-type dimers, namely, procyanidin A₁ and A₂. Results revealed that PSP-4 treatment prior H₂O₂ exposure increased cell activity and attenuated the cell cycle arrest and apoptosis rate. The H₂O₂-induced increase in intracellular reactive oxygen species (ROS) was remarkably inhibited by PSP-4. PSP-4 treatment enhanced the activity of catalase (CAT) and total super oxide dismutase (T-SOD) and restored glutathione (GSH) content, compared with the H₂O₂ treatment. Furthermore, the results indicated that PSP-4 protected DU145 cells by attenuating phosphorylation of the mitogen-activated protein kinases (MAPKs), by increasing the Bcl-2/Bax ratio, and by reducing the activation of caspase-3 and caspase-9 by cascade reactions. This study reveals that procyanidin A-type dimers from peanut skin have the potential function in preventing oxidative stress damage of prostatic cells.

Surface Functionalization with Proanthocyanidins Provides an Anti-Oxidant Defense Mechanism That Improves the Long-Term Stability and Osteogenesis of Titanium Implants

PURPOSE

Aseptic loosening is a major complication after total joint replacement. Reactive oxygen species generated by local tissue cells and liberated from implant surfaces have been suggested to cause implant failures. Surface modification of titanium (Ti)-based implants with proanthocyanidins (PAC) is a promising approach for the development of anti-oxidant defense mechanism to supplement the mechanical functions of Ti implants. In this study, a controlled PAC release system was fabricated on the surface of Ti substrates using the layer-by-layer (LBL) assembly.

MATERIALS AND METHODS

Polyethyleneimine (PEI) base layer was fabricated to enable layer-by-layer (LBL) deposition of hyaluronic acid/chitosan (HA/CS) multi-layers without or with the PAC. Surface topography and wettability of the fabricated HA/CS-PAC substrates were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier-transform infrared spectroscopy (FTIR) and contact angle measurement. PAC release profiles were investigated using drug release assays. MC3T3-E1 pre-osteoblast cells were used to assess the osteo-inductive effects of HA/CS-PAC substrates under conditions H2O2-induced oxidative stress in vitro. A rat model of femoral intramedullary implantation evaluated the osseo-integration and osteo-inductive potential of the HA/CS-PAC coated Ti implants in vivo.

RESULTS

SEM, AFM, FTIR and contact angle measurements verified the successful fabrication of Ti surfaces with multi-layered HA/CS-PAC coating. Drug release assays revealed controlled and sustained release of PAC over 14 days. In vitro, cell-based assays showed high tolerability and enhanced the osteogenic potential of MC3T3-E1 cells on HA/CS-PAC substrates when under conditions of H2O2-induced oxidative stress. In vivo evaluation of femoral bone 14 days after femoral intramedullary implantation confirmed the enhanced osteo-inductive potential of the HA/CS-PAC coated Ti implants.

CONCLUSION

Multi-layering of HA/CS-PAC coating onto Ti-based surfaces by the LBL deposition significantly enhances implant osseo-integration and promotes osteogenesis under conditions of oxidative stress. This study provides new insights for future applications in the field of joint arthroplasty.

Proanthocyanidins Protect against β-Hydroxybutyrate-Induced Oxidative Damage in Bovine Endometrial Cells

Metabolic diseases, such as ketosis, are closely associated with decreased reproductive performance (such as delayed estrus and decreased pregnancy rate) in dairy cows. The change of β-hydroxybutyrate (BHBA) concentration in dairy cattle is an important mechanism leading to ketosis, and its blood concentration in ketotic cows is always significantly higher than in nonketotic cows. Many studies indicated that BHBA can induce oxidative damage in liver and other organs. Proanthocyanidins (PCs) have gained substantial attention in the last decade as strong antioxidative substances. This study aimed to demonstrate a protective effect of PCs against BHBA-induced oxidative stress damage in bovine endometrial (BEND) cells by activating the nuclear erythroid2-related factor2 (Nrf2) signaling pathway. Our research show that PCs could significantly increase activities of catalase (CAT) and glutathione peroxidase (GSH-PX), glutathione (GSH) content, and antioxidant capacity (T-AOC), while significantly decreasing malondialdehyde (MDA) content in BEND cells. Both mRNA and protein expression levels of Nrf2 were significantly increased in BEND cells, and glutamate–cysteine ligase catalytic subunit (GCLC), heme oxygenase 1 (HO-1), manganese superoxide dismutase (Mn-SOD), and NAD(P)Hquinone dehydrogenase 1 (NQO-1) were also significantly increased. These results indicate that PCs can antagonize BHBA-induced oxidative damage by activating the Nrf2 signaling pathway to exert an antioxidant effect.

Proanthocyanidins against Oxidative Stress: From Molecular Mechanisms to Clinical Applications

Proanthocyanidins (PCs) are naturally occurring polyphenolic compounds abundant in many vegetables, plant skins (rind/bark), seeds, flowers, fruits, and nuts. Numerous in vitro and in vivo studies have demonstrated myriad effects potentially beneficial to human health, such as antioxidation, anti-inflammation, immunomodulation, DNA repair, and antitumor activity. Accumulation of prooxidants such as reactive oxygen species (ROS) exceeding cellular antioxidant capacity results in oxidative stress (OS), which can damage macromolecules (DNA, lipids, and proteins), organelles (membranes and mitochondria), and whole tissues. OS is implicated in the pathogenesis and exacerbation of many cardiovascular, neurodegenerative, dermatological, and metabolic diseases, both through direct molecular damage and secondary activation of stress-associated signaling pathways. PCs are promising natural agents to safely prevent acute damage and control chronic diseases at relatively low cost. In this review, we summarize the molecules and signaling pathways involved in OS and the corresponding therapeutic mechanisms of PCs.

Quantification of tannins and related polyphenols in commercial products of tormentil (Potentilla tormentilla)

INTRODUCTION

Potentilla tormentilla has many biological and pharmacological properties and can be used as an ingredient of some herbal medicines or beverages.

OBJECTIVE

The aim of this study was to evaluate the content of individual polyphenols, especially condensed and hydrolysable tannins in commercially available tormentil rhizomes and tinctures using chromatographic methods.

METHODS

A quantitative analysis (HPLC-PDA) was preceded by qualitative studies (UPLC-qTOF-MS/MS) and the isolation (CC) of the major tannin compounds.

RESULTS

The tested plant material is characterised by a high content of tannins and related polyphenols, i.e. in rhizomes even at the level above 20% and in tinctures above 2%. The main components of tormentil rhizomes are procyanidin B3 (mean ~ 3.6%), procyanidin C2 (mean ~ 2.8%), agrimoniin (mean ~ 2.5%), 3-O-galloylquinic acid (mean ~ 1.7%), catechin (mean ~ 1.6%), other flavan-3-ol oligomers (mean ~ 0.5-1.1) and laevigatins (mean ~ 0.2-0.6%). Free ellagic acid and glycosides of ellagic and methylellagic acids are secondary components.

CONCLUSIONS

Underground parts of tormentil are a source of oligomeric proanthocyanidins and ellagitannins, but in smaller quantity of gallotannins. Monogalloylquinic acids are new identified compounds, which had not been described in Potentilla tormentilla before we started our research. In the analysed tormentil tinctures agrimoniin concentration is lower in relation to other tannins.