Search Results (18)

Obesity and its associated metabolic disorders drive the search for natural compounds with anti-adipogenic properties. This study evaluated Vitis vinifera seed extract (GE), rich in oligomeric proanthocyanidins (OPCs), and Allium sativum bulb extract (ALL), rich in thiosulfinates, for their effects on adipogenesis and COX-related prostanoid modulation in 3T3-L1 cells. Differentiating preadipocytes were treated with non-cytotoxic concentrations of GE, ALL, or their combination (AGE) at a 1:600 dilution (approximately 23 μg/mL allicin and 0.05% OPCs). Lipid accumulation was assessed by Oil Red O staining, prostanoid levels (PGE₂, TXA₂, and PGI₂) were quantified by enzyme immunoassay, and adipogenic gene expression (PPARγ, CEBPα and GLUT4) was analyzed by RT-qPCR. All treatments reduced lipid accumulation, with GE showing the most potent inhibition (68.0% of control), followed by ALL (81.6%) and AGE (78.0%). Distinct prostanoid patterns emerged: GE increased both PGE₂ and PGI₂ and decreased TXA₂, while ALL increased PGE₂ and reduced both TXA₂ and PGI₂. The combination (AGE) did not enhance the anti-adipogenic effects. At the molecular level, GE downregulated PPARγ, CEBPα, and GLUT4, whereas ALL did not affect their transcription, indicating distinct mechanisms. These findings demonstrate that GE and ALL inhibit adipogenesis through differential modulation of the COX pathway and gene expression, highlighting their potential as functional ingredients for obesity management. The lack of synergy in the combination warrants further investigation. Full article

This study aimed to evaluate the potential of branches of black chokeberry, sea buckthorn, and black currant as raw materials for the development of pharmacologically active compounds, primarily oligomeric proanthocyanidins (OPCs), as they exhibit a broad spectrum of biological activities, including antioxidant, antimicrobial, anti-inflammatory, anticancer, etc. Branch biomass collected in spring and autumn of 2023–2025 was analyzed for its functional group profile and used for the isolation of OPCs with ethanol, an ethanol–water mixture (1:1, v/v), and an ethanol–acetone–water mixture (4:1:5, v/v/v). The highest yield of OPCs (up to 14% of DB) was achieved using the ethanol–acetone–water solvent mixture. Using LC-MS/MS, the OPC composition was analyzed and found to consist of dimers (m/z 577), trimers (m/z 865), and tetramers (m/z 1153). The maximum OPC content was observed in autumn samples. Mechanical pretreatment enhanced OPC accessibility by disrupting cell walls and increasing particle surface, facilitating release from the matrix and yielding up to 1.2-fold more OPCs than from untreated biomass. Quantification of 22 elements in the biomass by ICP-MS revealed low levels of toxic metals along with the presence of nutritionally relevant elements. Therefore, from a chemical safety perspective, biomass can be considered suitable for use as a source of OPCs. Full article

Background: Oligomeric proanthocyanidins (OPCs) are natural polyphenolic compounds with strong antitumor properties and have gained attention as potential agents to overcome drug resistance. Hepatocellular carcinoma (HCC) remains a major cause of cancer deaths worldwide, and although Lenvatinib is widely used, its effectiveness is limited by acquired resistance. This study explores the potential of OPCs to overcome Lenvatinib resistance in HCC. Methods: To evaluate the potential of OPCs to overcome Lenvatinib resistance in HCC, we established Lenvatinib-resistant Huh-7 and PLC-PRF-5 cell lines and conducted systematic cell culture experiments to assess their antitumor effects. Furthermore, genome-wide transcriptomic profiling, network pharmacology approaches, and pathway enrichment analysis were performed to identify resistance-associated signaling pathways that could serve as therapeutic targets. Results: The combination of OPCs and Lenvatinib demonstrated a significant synergistic anti-proliferative effect in resistant hepatocellular carcinoma cells, with the most synergistic dose combinations showing Bliss synergy scores exceeding 10. Transcriptomic profiling revealed that the adhesion molecule ITGA3 is a key factor in Lenvatinib resistance and contributes to the acquisition of anoikis resistance. The combination treatment suppressed ITGA3–EGFR–AKT signaling, restored anoikis sensitivity, significantly reduced spheroid formation (fold change = 0.10–0.12; p < 0.001), and markedly increased apoptosis (fold change = 2.7–5.0; p < 0.001). Conclusions: This study is the first to demonstrate that OPCs can overcome chemotherapy resistance by targeting the integrin pathway, providing scientific evidence for their potential use as an adjunctive therapy for chemotherapy-resistant HCC. Full article

Background/Objectives: Colorectal cancer (CRC) remains a major health challenge due to its high incidence and resistance to conventional therapies. Natural compounds have gained attention as potential adjuvant treatments. The study assesses whether combining Allium sativum and Vitis vinifera [rich in oligomeric proanthocyanidins condensed (OPCs)] extracts enhances cell viability reduction and migration inhibition. Methods: Human colorectal cancer cell lines (Caco-2 and HT-29) were treated with increasing concentrations of both extracts individually and in combination. Cell viability was assessed using MTT assays, while migration was evaluated through scratch wound assays. Synergistic effects were analyzed using Combenefit software. Results: Both extracts significantly reduced cell viability in a dose- and time-dependent manner. The combination of both extracts led to an enhanced reduction in cell viability, with a transient synergistic effect observed at 24 h in HT-29 cells. Regarding migration, OPCs showed a transient anti-migratory effect at 6 h in HT-29 cells, but no significant impact was observed in Caco-2 cells or at later time points. Conclusions: These findings suggest that Allium sativum and Vitis vinifera extracts have potential as complementary treatments for colorectal cancer, mainly through their effect on cell viability. This study opens a field of research on the possible therapeutic effects of natural extracts. Full article

Objectives: Modern lifestyles factors such as digital overload, aging, and poor sleep hygiene have led to increasing cases of sleep disturbances and inflammation-related disorders. These conditions are often associated with oxidative stress and immune dysregulation. Longan flower extract (LFE), traditionally used in East Asian medicine, has shown potential health benefits but remains scientifically underexplored. This study aims to investigate the chemical composition and bioactive effects of LFE on inflammation, oxidative stress, and melatonin biosynthesis in relevant cellular models. Methods: LFE was prepared using ethanol extraction and characterized for its total polyphenols, flavonoids, oligomeric proanthocyanidins (OPCs), and corilagin content via HPLC. Its anti-inflammatory, antioxidant, and neuroregulatory activities were assessed in LPS-stimulated RAW 264.7 macrophages and BV-2 microglial cells. Key assays included quantification of cytokines (TNF-α, IL-6), detection of nitric oxide (NO) and reactive oxygen species (ROS), and measurement of antioxidant enzyme activities (GPx, SOD). Gene expression of melatonin biosynthesis enzymes was evaluated using quantitative PCR. Results: LFE treatment significantly reduced LPS-induced TNF-α, IL-6, NO, and ROS production in both cell models. It enhanced GPx and SOD activity and increased intracellular glutathione levels. Moreover, LFE upregulated the expression of TPH1, DDC, AANAT, and ASMT, genes involved in melatonin biosynthesis, and promoted serotonin secretion. Conclusions: These findings suggest that LFE holds significant potential as a natural therapeutic supplement, particularly for alleviating sleep disturbances, reducing oxidative stress, and modulating inflammatory responses associated with modern lifestyle-related health conditions. Full article

Cadmium (Cd) is a toxic, non-essential metal that primarily enters animal bodies through the digestive and respiratory systems, leading to damage to multiple organs and tissues. Cd can accumulate in cartilage and induce damage to chondrocytes. Procyanidins (PAs), also known as concentrated tannic acid or oligomeric proanthocyanidins (OPCs), exhibit diverse biological and pharmacological activities. However, the mechanism of OPCs alleviates Cd-induced damage to chondrocytes in chickens remains to be further explored in vitro. Chondrocytes were isolated from both ends of the tibia of 17-day-old SPF chicken embryos, and then subsequently treated with various concentrations of Cd (0, 1, 2.5, 5, and 10 μmol/L) or OPCs (0, 5, 10, 20, and 40 μmol/L) to investigate the mechanism underlying extracellular matrix (ECM) degradation and damage. Cd reduced cell viability, glycosaminoglycan (GAG) secretion, and ECM degradation in chondrocytes by decreasing the expression of type II collagen alpha 1 (COL2A1) and aggrecan (ACAN) while increasing the release of cartilage oligomeric matrix protein (COMP), along with elevated levels of matrix-degrading enzymes, such as matrix metalloproteinases 1 (MMP1), MMP10, and MMP13, and a disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS4) and ADAMTS5. Cd induced phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2) and the expression of matrix-degrading enzymes, impairing ECM synthesis, an effect that could be alleviated by ERK1/2 inhibitor U0126. Chondrocytes were treated with 5 μmol/L Cd and 10 μmol/L OPCs, and it was found that OPCs inhibited the activation of the ERK1/2 signaling pathway and the expression of matrix-degrading enzymes, while promoting ECM synthesis and alleviating Cd-induced ECM damage in chickens. This study provides a theoretical basis for clinical research on OPCs with respect to the prevention and treatment of Cd-induced chondrogenic diseases in poultry. Full article

Osteocyte senescence is associated with skeletal dysfunction, but how to prevent bone loss and find the effective therapeutic targets is a potential scientific concern. Cadmium (Cd) is a widespread environmental contaminant that causes substantial bone damage in both animals and humans. Oligomeric proanthocyanidins (OPC) are naturally polyphenolic substances found in various plants and demonstrate significant anti-senescence potential. Here, we investigated the protective effects of OPC against Cd-induced senescence of osteocytes and identify potential regulatory mechanisms. OPC alleviated Cd-induced senescence of osteocytes by attenuating cell cycle arrest, reducing ROS accumulation, and suppressing pro-inflammatory responses in vitro. Furthermore, OPC effectively prevented the Cd-induced breakdown of dendritic synapses in osteocytes in vitro. Correspondingly, OPC ameliorated Cd-induced damage of osteocytes through anti-senescence activity in vivo. Taken together, our results establish OPC as a promising therapeutic agent that ameliorates Cd-induced osteocyte senescence by mitigating oxidative stress and inflammatory responses. Full article

Background: Grape seed extract (GSE) from Vitis vinifera L. is rich in polyphenols and oligomeric proanthocyanidin complexes (OPCs), and it has shown potential benefits in managing low mood and cognitive function. In this study, we investigated the potential bioactivities of Enovita^®, a standardized GSE extract (GSEe herein) rich in OPCs, in key mechanistic pathways related to low mood conditions and cognitive function. Methods: In vitro assays were conducted to assess GSEe’s inhibitory effects on γ-aminobutyric acid transaminase (GABA-T) and monoamine oxidase A (MAO-A), its binding affinity to the GABA site of GABA-A receptors, and its effects on acetylcholinesterase (AChE). Its neuroprotective effects on human SH-SY5Y neuroblastoma cells under oxidative stress (induced by H₂O₂) were assessed using MTT and LDH release assays. Its antioxidant activities were evaluated using DPPH, ABTS, FRAP, ORAC, HORAC, total phenolic content, and TAS assays. Its cytotoxicity was also evaluated. Results: GSEe showed significant GABA-T inhibitory activity. It also exhibited MAO-A and AChE inhibition, along with moderate binding affinity to the GABA-A receptor. In neuroprotective assays, GSEe provided significant protection to SH-SY5Y cells against oxidative stress. GSEe demonstrated robust antioxidant activity in all assays, including scavenging of DPPH and ABTS radicals, high ferric-reducing power, high polyphenolic contents, and a substantial total antioxidant capacity. Conclusions: GSEe exhibits promising bioactivities, highlighting its potential as a supplement for modulating mood and enhancing cognitive function. Overall, the promising results from these in vitro studies provide a strong foundation for the continued exploration and development of GSEe as a viable natural supplement for enhancing mental health and cognitive function. Full article

Chokeberries, which belong to the rose family (Rosaceae), have received increasing research attention due to their high content of secondary metabolites, especially oligomeric proanthocyanidins (OPCs). OPC-rich extracts are attributed to various positive health effects, including antioxidant or anti-inflammatory properties, which is why they are sold as food supplements. However, knowledge about the antioxidant properties of single OPCs is quite limited. Several separation steps with different separation techniques were performed to isolate OPCs from a pre-produced extract. More than 90 analytes were detected in the enriched fractions, which include eight OPCs, four cinchonains and one hexoside, including their respective isomers. For the characterization of the OPCs, high-resolution mass spectrometry coupled with liquid chromatography (LC-HRMS) was used. Based on the fragment spectra of the MS² experiments, conclusions about the fragmentation pathways and the structure of six new OPCs could be drawn. After isolating trimers, tetramers and pentamers, it was possible to test the antioxidant effect in relation to the individual degrees of polymerization (DP) or structures. The Trolox-equivalent antioxidant capacity (TEAC) test showed that all OPCs investigated exhibit antioxidant effects and a first correlation between the antioxidant effect and the DP could be postulated, which suggests new possibilities for the design of food supplements. Full article

This study was conducted to evaluate the oligomeric proanthocyanidins (OPC) in alleviating the detrimental effects of intestinal health caused by dietary histamine in juvenile American eels (Anguilla rostrata). A total of 480 fish with a similar body weight of 10.84 ± 0.16 g were randomly divided into four groups, and there were the control group fed a basal diet, the HIS group fed a diet with a high level of histamine (534 mg/kg), the H + OPC I group fed the high histamine diet with 300 mg/kg OPC, and the H + OPC II group fed the high histamine diet with 600 mg/kg OPC, respectiviely. After the fish were fed the trial diets for 77 days, the intestinal samples were taken, and the related parameters of intestinal health were analyzed. Dietary 300 mg/kg or 600 mg/kg OPC could reverse the decreased activities of lipase, protease, and glutathione peroxidase and the level of total antioxidant capacity, the increased intestinal malondialdehyde and D-lactate acid levels and the activity of diamine oxidase in serum, and the decreased villus height caused by a high level of dietary histamine. There were no significant differences above all the indices between the H + OPC I group and the H + OPC II group. The higher relative abundances of potentially pathogenic bacteria were induced by the high level of dietary histamine. Dietary 300 mg/kg OPC might increase the relative abundance of the potential probiotics and inhibit the colonization of intestinal pathogenic bacteria of juvenile American eels exposed to the stress of high dietary hisatamine. The intestinal health status of the H + OPC groups was similar to that of the control group. These results suggested that dietary 300 mg/kg OPC might alleviate the detrimental effects of dietary 534 mg/kg histamine on the intestine health of juvenile American eels by increasing the activity of digestive enzymes, improving the antioxidative potential and barrier function, and beneficially modulating the intestinal microbiota. Dietary 600 mg/kg OPC could not exert further improvement in growth performance and the intestinal health of juvenile American eels. Full article

Oligomeric Proanthocyanidins (OPCs), as a class of compounds widely found in plants, are particularly abundant in grapes and blueberries. It is a polymer comprising many different monomers, such as catechins and epicatechins. The monomers are usually linked to each other by two types of links, A-linkages (C-O-C) and B-linkages (C-C), to form the polymers. Numerous studies have shown that compared to high polymeric procyanidins, OPCs exhibit antioxidant properties due to the presence of multiple hydroxyl groups. This review describes the molecular structure and natural source of OPCs, their general synthesis pathway in plants, their antioxidant capacity, and potential applications, especially the anti-inflammatory, anti-aging, cardiovascular disease prevention, and antineoplastic functions. Currently, OPCs have attracted much attention, being non-toxic and natural antioxidants of plant origin that scavenge free radicals from the human body. This review would provide some references for further research on the biological functions of OPCs and their application in various fields. Full article

Oligomeric proanthocyanidins (OPCs) are abundant polyphenols found in foods and botanicals that benefit human health, but our understanding of the functions of OPCs in rice plants is limited, particularly under cold stress. Two rice genotypes, named Zhongzao39 (ZZ39) and its recombinant inbred line RIL82, were subjected to cold stress. More damage was caused to RIL82 by cold stress than to ZZ39 plants. Transcriptome analysis suggested that OPCs were involved in regulating cold tolerance in the two genotypes. A greater increase in OPCs content was detected in ZZ39 than in RIL82 plants under cold stress compared to their respective controls. Exogenous OPCs alleviated cold damage of rice plants by increasing antioxidant capacity. ATPase activity was higher and poly (ADP-ribose) polymerase (PARP) activity was lower under cold stress in ZZ39 than in RIL82 plants. Importantly, improvements in cold tolerance were observed in plants treated with the OPCs and 3-aminobenzamide (PARP inhibitor, 3ab) combination compared to the seedling plants treated with H₂O, OPCs, or 3ab alone. Therefore, OPCs increased ATPase activity and inhibited PARP activity to provide sufficient energy for rice seedling plants to develop antioxidant capacity against cold stress. Full article

It is important to inhibit oxidative stress to maintain sperm motility during cryopreservation. The present study was performed to investigate the effects of supplementing oligomeric proanthocyanidins (OPC) and bamboo leaf flavonoids (BLF) or their combination as an extender for Simmental bull semen freezing. OPC, BLF, or their combination were added to the frozen diluent of bovine semen. Afterwards, computer-assisted semen analysis (CASA), detection of membrane functionality, acrosome integrity, mitochondrial integrity, CAT, SOD, GSH-PX, MDA, and ROS were conducted. The results showed that adding 50 mg/L OPC or 4 mg/L BLF could improve the quality of frozen sperm. Compared with 50 mg/L OPC alone, the combination of 50mg/L OPC and 2 mg/L BLF significantly increased the kinematic parameters of sperm, and sperm CAT, GSH-PX and SOD levels (p < 0.05), whereas the MDA of sperm was decreased (p < 0.05). These results indicated that compared to the addition of 50 mg/L OPC alone, a combination of 50 mg/L OPC and 2 mg/L BLF could further improve the quality of frozen semen. The results could provide theoretical data support for the development of a new protective agent and are significant for the cryopreservation of bovine semen in the future. Full article

This study aimed to improve the quality of freeze-dried yellow peaches (Amygdalus persica). Yellow peaches were pretreated with osmotic dehydration for 15 min prior to vacuum-freeze drying and supplemented with different ultrasonic power levels (180 W, 240 W, 300 W) and a curing agent (calcium lactobionate, CaLa) to investigate the effects on the quality of freeze-dried yellow peach slices. After vacuum freeze-drying the yellow peach slices for 48 h, their moisture, color, texture, microstructure, total phenol (TP) content and oligomeric proantho-cyanidin (OPC) content were determined. It was found that the auxiliary ultrasonic power with various levels, especially powered at 240 W, produced very favorable effects on the quality characteristics of freeze-dried yellow peaches. The average pore size of USOD-240 W samples was reduced by 57.07% compared with that of the FD samples. In terms of nutrient maintenance, USOD-240 W can also prevent nutrient loss to the greatest extent. The TP content (5.40 mg/g) and OPC content (14.42 mg/g) were always highest in each pretreatment. The addition of CaLa can further improve the quality of yellow peach slices. Overall, the application of ultrasound and CaLa to improve the quality of freeze-dried yellow peach slices along with osmotic dehydration before freeze-drying is a method worth considering. Full article

This study investigated the possible enhancement of berberine’s (BB) hypoglycemic activity by oligomeric proanthocyanidins (OPCs) and its underlying mechanism. The hypoglycemic activity of the studied compounds was evaluated in diabetic db/db mice. The cellular uptake and efflux of BB with or without OPCs were investigated using Caco-2 intestinal cells. A pharmacokinetic study of BB and OPCs was performed in Sprague Dawley (SD) mice by oral administration of the study compounds. Liquid chromatography–tandem mass spectrometry (LC–MS/MS) was employed to determine the cellular efflux, retention, and the serum concentrations of the compounds. The results revealed that OPCs considerably potentiated the hypoglycemic efficacy of BB in diabetic db/db mice. In the in vitro experiments, OPCs significantly inhibited the efflux and increased the uptake of the P-glycoprotein (P-gp) substrate rhodamine-123 (R123) and BB in Caco-2 intestinal cells. Moreover, OPCs substantially reduced the expression of P-gp in Caco-2 cells. The inhibition of BB efflux by OPCs was translated into the improved pharmacokinetics in vivo. When co-administered, OPCs obviously increased the average maximum concentration of BB in mice. In summary, this study demonstrated that combination of BB with OPCs could significantly improve the pharmacokinetics and hypoglycemic efficacy of BB, which is valuable for future exploration of the combination of BB and OPCs as oral hypoglycemic agents. Full article