Catechin Group Research Articles

Comprehensive Isolation and Characterization of Theaflavins, Thearubigins and Caffeine as Bioactive Compounds from Darjeeling Black Tea

The present study aimed to isolate and characterize three major bioactive components viz. theaflavins, thearubigins and caffeine from Darjeeling black tea, which contribute significantly to the cup characteristics and health benefits of black tea. Theaflavins were isolated using Soxhlet extraction followed by column chromatography, HPLC and UV spectroscopy. HPLC showed effective separation of four major theaflavins. Thearubigins were isolated using liquid-liquid extraction and characterized through NMR, FTIR-ATR and UV spectroscopic techniques. The NMR spectral studies suggested thearubigins to be polymeric oxidation products of catechin groups, while FTIR spectral studies indicated similarity with proanthocyanidin-like polymers. Caffeine was isolated via a solid-liquid extraction followed by liquid-liquid extraction and identified using TLC, NMR, UV and SEM techniques. TLC showed an Rf value of 0.65, which is consistent with standard caffeine. The NMR confirmed the purity of isolated caffeine and SEM revealed its needle-shaped crystal morphology. The results show that these bioactive compounds may be efficiently isolated and characterized using chromatographic and spectroscopic methods.

Catechin Protects against Lipopolysaccharide-induced Depressive-like Behaviour in Mice by Regulating Neuronal and Inflammatory Genes.

Many studies have suggested that tea has antidepressant effects; however, the underlying mechanism is not fully studied. As the main anti-inflammatory polyphenol in tea, catechin may contribute to the protective role of tea against depression. The objective of this study is to prove that catechin can protect against lipopolysaccharide (LPS)-induced depressive-like behaviours in mice, and then explore the underlying molecular mechanisms. Thirty-one C57BL/6J mice were categorized into the normal saline (NS) group, LPS group, catechin group, and amitriptyline group according to their treatments. Elevated Plus Maze (EPM), Tail Suspension Test (TST), and Open Field Test (OFT) were employed to assess depressive- like behaviours in mice. RNA sequencing (RNA-seq) and subsequent Bioinformatics analyses, such as differential gene analysis and functional enrichment, were performed on the four mouse groups. In TST, the mice in the LPS group exhibited significantly longer immobility time than those in the other three groups, while the immobility times for the other three groups were not significantly different. Similarly in EPM, LPS-treated mice exhibited a significantly lower percentage in the time/path of entering open arms than the mice in the other three groups, while the percentages of the mice in the other three groups were not significantly different. In OFT, LPS-treated mice exhibited significantly lower percentages in the time/path of entering the centre area than those in the other three groups. The results suggested that the LPS-induced depression models were established successfully and catechin can reverse (LPS)-induced depressive-like behaviours in mice. Finally, RNA-seq analyses revealed 57 differential expressed genes (DEGs) between LPS and NS with 19 up-regulated and 38 down-regulated. Among them, 13 genes were overlapped with the DEGs between LPS and cetechin (in opposite directions), with an overlapping p-value < 0.001. The 13 genes included Rnu7, Lcn2, C4b, Saa3, Pglyrp1, Gpx3, Lyz2, S100a8, S100a9, Tmem254b, Gm14288, Hbb-bt, and Tmem254c, which might play key roles in the protection of catechin against LPS-induced depressive-like behaviours in mice. The 13 genes were significantly enriched in defense response and inflammatory response, indicating that catechin might work through counteracting changes in the immune system induced by LPS. Catechin can protect mice from LPS-induced depressive-like behaviours through affecting inflammatory pathways and neuron-associated gene ontologies.

(+)-Catechin attenuates CCI-induced neuropathic pain in male rats by promoting the Nrf2 antioxidant pathway to inhibit ROS/TLR4/NF-κB-mediated activation of the NLRP3 inflammasome.

The objective of this study was to investigate the potential mechanisms by which (+)-catechin alleviates neuropathic pain. Thirty-two male Sprague-Dawley rats were divided into four groups: the sham group, the chronic constriction injury (CCI)group, the CCI+ ibuprofen group, and the CCI+ (+)-catechin group. CCI surgery induces thermal hyperalgesia in rats and (+)-catechin ameliorated CCI-induced thermal hyperalgesia and repaired damaged sciatic nerve in rats. CCI decreased SOD levels in male rat spinal cord dorsal horn and promoted MDA production, induced oxidative stress by increasing NOX4 levels and decreasing antioxidant enzyme HO-1 levels, and also increased protein levels of TLR4, p-NF-κB, NLRP3 inflammasome components, and IL-1β. In contrast, (+)-catechin reversed the above results. In i vitro experiments, (+)-catechin reduced the generation of reactive oxygen species (ROS) in GMI-R1 cells after LPS stimulation and attenuated the co-expression of IBA-1 and NLRP3. It also showed significant inhibition of the NF-κB and NLRP3 inflammatory pathways and activation of the Nrf2-mediated antioxidant system. Overall, these findings suggest that (+)-catechin inhibits the activation of the NLRP3 inflammasome through the triggering of the Nrf2-induced antioxidant system, the inhibition of the TLR4/NF-κB pathway, and the production of ROS to alleviate CCI-induced neuropathic pain in male rats.

Oral administration of encapsulated catechin in chitosan-alginate nanoparticles improves cognitive function and neurodegeneration in an aluminum chloride-induced rat model of Alzheimer's disease.

The present study aimed to investigate the effect of catechin-loaded Chitosan-Alginate nanoparticles (NPs) on cognitive function in an aluminum chloride (AlCl3)-induced rat model of Alzheimer's disease (AD). The Catechin-loaded Chitosan-Alginate nanocarriers were synthesized through ionotropic gelation (IG) method. Physio-chemical characterization was conducted with the Zetasizer Nano system, the scanning electron microscope, and the Fourier transform infrared spectroscopy. The experiments were performed over 21 days on six groups of male Wistar rats. The control group, AlCl3 treated group, Catechin group, nanocarrier group, treatment group 1 (AlCl3 + Catechin), and treatment group 2 (AlCl3 + nanocarrier). A behavioral study was done by the Morris water maze (MWM) test. In addition, the level of oxidative indices and acetylcholine esterase (AChE) activity was determined by standard procedures at the end of the study. AlCl3 induced a significant increase in AChE activity, along with a significant decrease in the level of Catalase (CAT) and total antioxidant capacity (TAC) in the hippocampus. Moreover, the significant effect of AlCl3 was observed on the behavioral parameters of the MWM test. Both forms of Catechin markedly improved AChE activity, oxidative biomarkers, spatial memory, and learning. The present study indicated that the administration of Catechin-loaded Chitosan-Alginate NPs is a beneficial therapeutic option against behavioral and chemical alteration of AD in male Wistar rats.

(+)-Catechin Alleviates CCI-Induced Neuropathic Pain in Rats by Modulating the IL34/CSFIR Axis and Attenuating the Schwann Cell-Macrophage Cascade Response in the DRG.

The aim of this study was to investigate the potential therapeutic applications of (+)-catechin in the treatment of neuropathic pain. In vivo study, 32 SD rats were randomly divided into four groups: sham group, chronic constriction injury (CCI) group, CCI + ibuprofen group and CCI+ (+)-catechin group. They were subjected to behavioural tests, ELISA, immunohistochemistry and Western blotting. The mechanisms involved were investigated using specific inhibitors in cell experiments. Results of in vivo experiments showed that (+)-catechin could reduce the cold sensitivity pain in a rat model of CCI; ELISA and immunohistochemistry results showed that (+)-catechin could decrease the levels of IL-8, IL-6, TNF-α, CCL2 and CCL5 in serum and the expression levels of nNOS, COX2, IL6, TNF-α, IBA-1 and CSF1R in DRG of CCI rats. Finally, western blot confirmed that (+)-catechin could diminish the levels of IL-34/CSF1R/JAK2/STAT3 signalling pathway in DRG of CCI rats. In vitro studies showed that (+)-catechin reduced IL-34 secretion in LPS-induced RSC96 cells. Meanwhile, (+)-catechin administration in LPS-induced Schwann cell-conditioned medium (L-CM) significantly inhibited the proliferation and migration of RAW264.7 cells; in addition, L-CM+(+)-catechin reduced the activation of the CSF1R/JAK2/STAT3 signalling pathway. (+)-Catechin attenuated the Schwann cell-macrophage cascade response in the DRG by modulating the IL34/CSFIR axis and inhibiting activation of the JAK2/STAT3 pathway, thereby attenuating CCI-induced neuropathic pain in rats.

The Effects of Structure and Oxidative Polymerization on Antioxidant Activity of Catechins and Polymers.

Polyphenols are key free radical scavengers in tea. This study screened the antioxidant active groups of catechins and dimers and analyzed the effects of the degree of oxidative polymerization and oxidative dimerization reaction on their antioxidant activities. ABTS+· free radical scavenging activity, DPPH free radical scavenging activity, and total antioxidant capacity of catechins and polymers were systematically analyzed and compared in this study. Results manifested antioxidant activities of catechins were dominated by B-ring pyrogallol and 3-galloyl, but were not decided by geometrical isomerism. 3-galloyl had a stronger antioxidant activity than B-ring pyrogallol in catechins. The number, not the position, of the galloyl group was positively correlated with the antioxidant activities of theaflavins. Theasinensin A has more active groups than (-)-epigallocatechin gallate and theaflavin-3,3'-digallate, so it had a stronger antioxidant activity. Additionally, the higher the degree of oxidation polymerization, the weaker the antioxidant activities of the samples. The oxidative dimerization reaction hindered the antioxidant activities of the substrate-catechin mixture by reducing the number of active groups of the substrate and increasing the molecular structure size of the product. Overall, pyrogallol and galloyl groups were antioxidant active groups. The degree of oxidative polymerization and the oxidative dimerization reaction weakened the antioxidant activity.

Combining nano-curcumin with catechin improves COVID-19-infected patient's inflammatory conditions

AimsA hyperinflammatory condition is brought on by the development of Coronavirus disease 2019 (COVID-19), which is characterized by an elevation of T helper (Th) 17 cells, high levels of pro-inflammatory cytokines, and a depletion of regulatory T (Treg) cells. MethodsIn this research, we examined the effect of nano-curcumin and catechin on the TCD4+, TCD8+, Th17, and Treg cells and their associated factors in COVID-19 patients. For this purpose, 160 (50 patients excluded during the study) COVID-19 patients were divided into four groups: placebo, nano-curcumin, catechin, and nano-curcumin + catechin. The frequency of TCD4+, TCD8+, Th17, and Treg cells, the gene expression of transcription factors (STAT3, RORt, and FoxP3) relevant to Th17 and Treg, as well as the serum levels of cytokines (IL-6, IL17, IL1-b, IL-10, and TGF-), were all evaluated intra- and inter-group, before and after treatment, in all groups. ResultsOur study showed that TCD4 + and TCD8 + cells were significantly higher in the nano-curcumin + catechin group compared to the control group, whereas Th17 was lower than the initial value. Furthermore, compared to the placebo-received group, cytokines and transcription factors associated with Th17 were significantly lower in the nano-curcumin + catechin group. Additionally, combined therapy increased Treg cells and transcription factors compared to the placebo group. ConclusionOverall, our results show that combining nano-curcumin with catechin has a more notable impact on the enhancement of TCD4+, TCD8+, and Treg cells, as well as a decrease in Th17 cells and their mediators, suggesting a promising combination therapy in reducing the inflammatory conditions of COVID-19 infected patients.

Enhancement of Neprilysin Activity by Natural Polyphenolic Compounds and Their Derivatives in Cultured Neuroglioma Cells.

The onset of Alzheimer's disease (AD) is characterized by accumulation of amyloid β peptide (Aβ) in the brain. Neprilysin (NEP) is one of the major Aβ-degrading enzymes. Given findings that NEP expression in the brain declines from the early stage of AD before apparent neuronal losses are observed, enhancement of NEP activity and expression may be a preventive and therapeutic strategy relevant to disease onset. We screened for compounds that could enhance the activity and expression of NEP using a polyphenol library previously constructed by our research group and investigated the structure-activity relationships of the identified polyphenols. We found that amentoflavone, apigenin, kaempferol, and chrysin enhanced the activity and expression of NEP, suggesting that chemical structures involving a double bond between positions 2 and 3 in the C ring of flavones are important for NEP enhancement, while catechol or pyrogallol structures, except for the galloyl group of catechins, abolished these effects. Moreover, natural compounds, such as quercetin, were not effective per se, but were changed to effective compounds by adding a lipophilic moiety. Using our study findings, we propose improvements for dietary habits with experimental evidence, and provide a basis for the development of novel small molecules as disease-modifying drugs for AD.

고온 환경에서 카테킨 및 비타민 C 첨가가 육계의 생산성, 계육품질, 혈액성분 및 스트레스 지표에 미치는 영향

The study was carried out to investigate the effects of dietary combined supplementation of antioxidants as catechin and vitamin C on growth performance, meat quality, blood profiles and stress responses of broilers exposed to high temperature. For this experiment, a total of 360 21-day-old male Ross 308 broilers were used. Treatments were assigned with 6 replicates per treatment and 10 birds per replicate in a 2 × 3 factorial design with vitamin C (0, 250 mg/kg) and catechin (0, 600, 1,200 mg/kg). The heat stress environment was maintained at temperature 32±1°C and relative humidity 60±5% for 24 hours until the end of the experiment. The supplemented antioxidants had no significant difference in weight gain, feed intake and feed conversion ratio (<i>P</i>&gt;0.05). The content of total cholesterol in blood had no interaction, but decrease (<i>P</i>&lt;0.01) in the supplemented catechin group. Also, the supplementation with catechin showed increase in the SOD activity of blood, and lower corticosterone and IgM levels of broilers. The contents of HSP70 and MDA in liver decrease (<i>P</i>&lt;0.05) with the supplementation of antioxidants, and HSP70 showed an interaction between groups. DPPH radical scavenging ability in breast meat increased (<i>P</i>&lt;0.01) in catechin, but meat quality did not show difference according to treatments. Respiratory rate decreased (<i>P</i>&lt;0.05) in catechin, but no interaction with vitamin C. In conclusion, the combination of vitamin C and catechin can alleviate stress under high temperature, such as HSP70 and MDA, but further study on the optimal supplemental level is needed.

Structural modification of alkali lignin into higher performance energy storage materials： Demethylation and cleavage of aryl ether bonds

Lignin is extensively studied to be used as an energy storage material due to its intrinsic catechin structure. However, the limited content of catechin groups in industrial lignin is not enough to satisfy the demand for highly charged storage devices. Herein, the pseudocapacitance of lignin itself is further improved by demethylation and cleavage of aryl ether bonds of alkali lignin (AL) using the HBr/LiBr system. The phenolic hydroxyl (Ar-OH) group content of the demethylation alkali lignin (DAL, up to 2.99 mmol∙L−1) is 1.85 times higher than that of AL. The as-prepared [email protected] reduced graphene oxide (rGO) composites obtained from DAL and graphene oxide (GO) showed excellent energy storage capacity (414.5 F∙g−1), which increased by 96.60% compared to the [email protected] composites. More significantly, the [email protected] materials displayed excellent rate capacity, and its capacitance retention rate reached 76.91%. Therefore, this strategy of structural modification of lignin is effective for improving its energy storage performance, which will provide a possibility for the development of lignin into higher-performance energy storage materials.

Preparation and Properties of Double-Crosslinked Hydroxyapatite Composite Hydrogels.

Natural polymer hydrogels have good mechanical properties and biocompatibility. This study designed hydroxyapatite-enhanced photo-oxidized double-crosslinked hydrogels. Hyaluronic acid (HA) and gelatin (Gel) were modified with methacrylate anhydride. The catechin group was further introduced into the HA chain inspired by the adhesion chemistry of marine mussels. Hence, the double-crosslinked hydrogel (HG) was formed by the photo-crosslinking of double bonds and the oxidative-crosslinking of catechins. Moreover, hydroxyapatite was introduced into HG to form hydroxyapatite-enhanced hydrogels (HGH). The results indicate that, with an increase in crosslinking network density, the stiffness of hydrogels became higher; these hydrogels have more of a compact pore structure, their anti-degradation property is improved, and swelling property is reduced. The introduction of hydroxyapatite greatly improved the mechanical properties of hydrogels, but there is no change in the stability and crosslinking network structure of hydrogels. These inorganic phase-enhanced hydrogels were expected to be applied to tissue engineering scaffolds.

Dietary Flavonoids with Catechol Moiety Inhibit Anticancer Action of Bortezomib: What about the other Boronic Acid-based Drugs?

Approval of the first boronic acid group-containing drug, bortezomib, in 2003 for the treatment of multiple myeloma sparked an increased interest of medicinal chemists in boronic acidbased therapeutics. As a result, another boronic acid moiety-harboring medication, ixazomib, was approved in 2015 as a second-generation proteasome inhibitor for multiple myeloma; and dutogliptin is under clinical investigation in combination therapy against myocardial infarction. Moreover, a large number of novel agents with boronic acid elements in their structure are currently in intensive preclinical studies, allowing us to suppose that at least some of them will enter clinical trials in the near future. On the other hand, only some years after bortezomib approval, direct interactions between its boronic acid group and catechol moiety of green tea catechins as well as some other common dietary flavonoids like quercetin and myricetin were discovered, leading to the formation of stable cyclic boronate esters and abolishing the anticancer activities. Although highly relevant, to date, no reports on possible co-effects of catechol group-containing flavonoids with new-generation boronic acidbased drugs can be found. However, this issue cannot be ignored, especially considering the abundance of catechol moiety-harboring flavonoids in both plant-derived food items as well as over-thecounter dietary supplements and herbal products. Therefore, in parallel with the intensified development of boronic acid-based drugs, their possible interactions with catechol groups of plant-derived flavonoids must also be clarified to provide dietary recommendations to patients for maximizing therapeutic benefits. If concurrently consumed flavonoids can indeed antagonize drug efficacy, it may pose a real risk to clinical outcomes.

Novel Electrochemical Sensing of Catechins in Raw Green Tea Extract via a Trimetallic Zeolitic Imidazolate Fibrous Framework

Human health-related issues are increasing in day to day life because of the modern and unhygienic food lifestyles. In recent times, green tea (GT) gains more attention due to its numerous health benefits. It contains more biologically active compounds that improve mental health, increase metabolism, reduce cancer risks, and serve as an anti-aging agent for the brain. As it is globally consumed, the evaluation of the compounds present in it is very important. Hence, an attempt has been performed to evaluate these components in GT by using a cobalt nickel iron-based trimetallic zeolitic imidazolate framework as microfibers (CoNiFe-ZIF-MFs) synthesized via an electrospinning technique. Interestingly, the synthesized CoNiFe-ZIF-MFs catalyst simultaneously detects three major catechin (CT) groups, namely, epigallocatechin-3-gallate (EGCG), epicatechin (EC), and epicatechingallate (ECG). Further, the square wave voltammetry findings showed that there is a wide linear range of 50 ng to 1 mg for all the three CTs with LODs 45, 8, and 4 ng for EGCG, EC, and ECG, respectively. These results confirm the excellent sensing behavior of the composite toward GT extracts, proposing its practical utility in real-time compound analysis in food sectors. Other results like stability and reproducibility also promote its usage in the biomedical field. This study mainly focuses on the direct sensing of CTs present in GT without spiking any commercially purchased sample, and the sensing was performed simultaneously for all the three analytes; thus, this work gains novelty from the existing ones.

Effect of Catechins on Upper Respiratory Tract Infections in Winter: A Randomized, Placebo-Controlled, Double-Blinded Trial.

Tea catechins are plant-derived compounds that improve immune functions. Previous randomized control trials have demonstrated the efficacy of primarily epi-type catechins against upper respiratory tract infections (URTIs). Green tea can be consumed in several ways, including popular bottled beverages. These beverages, however, require sterilization during manufacturing, which results in catechin isomerization. We conducted a randomized, double-blinded, placebo-controlled trial involving healthy Japanese participants to evaluate whether catechin consumption via bottled beverages has an alleviating effect on the duration and severity of URTIs in winter. The catechin group (490 mg catechin, 0.14%, containing 59% epi-type catechin, n = 55) showed reduced durations of running nose, nasal congestion, and headache, compared with the placebo group (0 mg catechin, n = 54; p = 0.013, 0.018, and <0.001, respectively). Furthermore, when considering physical symptoms, the duration of nasopharyngeal symptoms improved significantly in the catechin group (p < 0.001) compared with that in the control group. The daily consumption of catechin thus reduced the duration and severity of URTIs in healthy men and women. Humans are regularly exposed to several potential infectious threats, and the oral administration of heat-epimerized tea catechins might help prevent and reduce the severity of URTIs.

Flavonoid Compounds of the Catechin from Wungu (Graptophyllum pictum (L.) Griff) Leaves and the Sun Protecting Factor Value

The flavonoid content in wungu (Graptophyllum pictum (L.) Griff.) leaves has the potential as a sunscreen. The study aims to identify isolates of flavonoid compounds from wungu leaves and determine the SPF value. Steps are followed by extraction, fractionation, phytochemical test, separation by chromatography, identification, and SPF test. Extraction was carried out with methanol, followed by fractionation with n-hexane and dichloromethane. Dichloromethane fraction was chosen to proceed to the separation step because the results of the phytochemical test showed a vigorous color intensity for the content of flavonoids. The isolate (3.6 mg; dark green; amorphous; mp. 132-136 °C) was identified using a UV-Vis spectrophotometer using methanol as a solvent with a shift reagent NaOH, AlCl3, and a mixture of concentrated AlCl3 and HCl. Based on the UV-Vis spectra, the isolate was predicted to be flavonoid compounds belonging to the catechin group, which have a hydroxyl group at positions C-3, C-7, and do not have an ortho-hydroxy group in ring B. The SPF value of the isolate of 2.3244 at 100 ppm was determined in vitro and calculated by the Qian equation. Therefore, isolate was categorized as sunscreens that provided minimal protection

Flavonoid‐enriched diets improved the growth and flesh quality of grass carp ( Ctenopharyngodon idellus ) based on metabolomics

This study investigated the effects of four flavonoids on growth and flesh quality of grass carp (Ctenopharyngodon idellus). Five diets were designed with the supplementation of quercetin (QC), rutin (RT), baicalein (BC) and catechin (CC) in basal diet (control) and were fed to grass carp (59.7 ± 0.2 g) for 60 days. The fish fed QC and RT diets, rather than BC and CC diets, showed higher weight gain (+4.0%, +3.9%) and lower feed conversion ratio (−0.07, −0.06) than the control fish. The contents of total collagen, heat-soluble collagen, total free amino acids and flavour amino acids in flesh were significantly increased by the supplementation of QC and RT in diets. The SOD activity and the contents of C22:5, C22:6 and n-3 PUFA were significantly increased, and the malondialdehyde and protein carbonyl contents were significantly decreased in the QC, RT and CC groups. In the metabolomics profiling of muscle, 102 and 68 named differential metabolites were identified in the QC and RT groups, and these metabolites were found to be involved in the pathways of “lipid metabolism” and “amino acid metabolism.” In addition, the mRNA expressions of IGF-1, PI3K, AKT and FAS in flesh were significantly up-regulated in QC and RT groups. In summary, dietary QC and RT promoted the growth and flesh quality of grass carp which might be associated with IGF-1/TOR, Nrf2, TGF-β/Smad4 and PPAR signalling pathway.

Lipophilization and amylose inclusion complexation enhance the stability and release of catechin

Catechin is a natural phenolic compound with various bioactivities. However, it is unstable under light and heat environments. Amylose can form a single helical hydrophobic cavity to encapsulate and protect bioactive compounds. In this work, we applied amylose inclusion complexes (IC) to encapsulate a lipophilized catechin, i.e., hexadecyl catechin (HC), to improve its photostability and thermal stability. The formation of amylose-HC IC was characterized using differential scanning calorimetry, X-ray diffraction, and Fourier transform infrared spectroscopy. The photostability and thermal stability studies showed that the retention of guest molecules in IC was 86.1% ± 5.1% and 87.4% ± 0.6%, respectively, which was significantly higher than that of the catechin, HC, and amylose-HC physical mixture groups. Moreover, the in vitro release profile of IC demonstrated a steady and complete release of catechin. The findings show the amylose encapsulation of catechin is a promising technique to preserve bioactive compounds in food.

Persimmon-derived tannin ameliorates the pathogenesis of ulcerative colitis in a murine model through inhibition of the inflammatory response and alteration of microbiota

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) induced by dysregulation of the immune response in the intestinal mucosa. Although the underlying mechanisms of UC development are not fully understood, disruption of gut microbiota, “dysbiosis”, is thought to lead to the development of IBD. Persimmon (Ebenaceae Diospyros kaki Thunb.)-derived tannin, which is a condensed polymeric tannin consisting of catechin groups, has antioxidant, anti-inflammatory, and antimicrobial activities. In this study, we assessed the effect of persimmon-derived tannin on a murine model of UC established by dextran sulfate sodium-induced colitis in female mice. Dietary supplementation of tannin significantly decreased disease activity and colon inflammation. A hydrolysate of tannin directly suppressed expression of inflammatory genes in macrophages in vitro. In faecal microbiota, the relative abundance of Bacteroides was increased significantly by tannin supplementation. Alpha-diversity indices in colitis-induced mice were significantly higher in the tannin diet group compared with the control diet group. Additionally, expansion of Enterobacteriaceae and Enterococcus, which is associated with disease progression of IBD, was remarkably suppressed in the tannin diet group. These results suggest that persimmon-derived tannin ameliorates colon inflammation in UC through alteration of the microbiota composition and immune response, which may be a promising candidate for IBD therapy.

Transcriptomic and Translatomic Analyses Reveal Insights into the Developmental Regulation of Secondary Metabolism in the Young Shoots of Tea Plants (Camellia sinensis L.).

Accumulation of secondary metabolites in the young shoots of tea plants is developmentally modulated, especially flavonoids. Here, we investigate the developmental regulation mechanism of secondary metabolism in the developing leaves of tea plants using an integrated multiomic approach. For the pair of Leaf2/Bud, the correlation coefficient of the fold change of mRNA and RPFs abundances involved in flavonoid biosynthesis was 0.9359, being higher than that of RPFs and protein (R2 = 0.6941). These correlations were higher than the corresponding correlation coefficients for secondary metabolisms and genome-wide scale. Metabolomic analysis demonstrates that the developmental modulations of the structural genes for flavonoid biosynthesis-related pathways align with the concentration changes of catechin and flavonol glycoside groups. Relatively high translational efficiency (TE > 2) was observed in the four flavonoid structural genes (chalcone isomerase, dihydroflavonol 4-reductase, anthocyanidin synthase, and flavonol synthase). In addition, we originally provided the information on identified small open reading frames (small ORFs) and main ORFs in tea leaves and elaborated that the presence of upstream ORFs may have a repressive effect on the translation of downstream ORFs. Our data suggest that transcriptional regulation coordinates with translational regulation and may contribute to the elevation of translational efficiencies for the structural genes involved in the flavonoid biosynthesis pathways during tea leaf development.

Assessment of preclinical effect of (+)-catechin hydrate on sexual function: An in silico and in vivo study.

Considering dopamine-enhancing effect of (+)-catechin, the present study was designed to evaluate dopamine-2 (D2) receptor agonistic and phosphodiesterase-5 (PDE5) enzyme inhibitory effects in in silico and effect on male sexual function of Sprague Dawley rats in vivo. (+)-Catechin and standard (sildenafil and bromocriptine) were docked using Autodock Vina 1.1.2 and visualised by UCSF Chimera 1.14. Significant interactions in terms of binding energies were observed for catechin with both proteins. In in vivo study, the rats were dosed orally for 54days with (+)-catechin hydrate (50mg/kg), sildenafil citrate (standard, 4mg/kg) and carboxymethylcellulose (vehicle, 0.25%w/v). The aphrodisiac effects were evaluated on the day 14, 28, 42 and 54 using the behavioural parameters of mounting and intromission. After the study, animals were sacrificed and testes and spermatozoa were assessed for safety profile. Results showed a significant increase in mount and intromission frequencies and a significant reduction in mount and intromission latencies in the catechin group on all tested days when compared to vehicle control. (+)-Catechin was found to be safe on histology of testes, sperm count, sperm motility and sperm morphology parameters. In conclusion, catechin demonstrated an enhancement in sexual behaviour without eliciting toxicity on the male reproductive system in rats.