Activity and potential mechanisms of action of persimmon tannins according to their structures: A review.

One distinguishing feature of the persimmon, that differentiates it from other fruits, is its high proanthocyanidins content, known as persimmon tannin (PT). Despite the poor absorption of PT in the small intestine, results from animal studies demonstrate that PT has many health benefits. Our goal in this review is to summarize the literature that elucidates the relationship between PT structure and activity. In addition, we also summarize the potential mechanisms underlying the health benefits that result from PT consumption; this includes the hypolipidemic, hypoglycemic, antioxidant, anti-inflammatory, antiradiation, antibacterial and antiviral, detoxification effects on snake venom, and the absorption of heavy metals and dyes. Studies show that PT is a structurally distinct proanthocyanidins that exhibits a high degree of polymerization. It is galloylation-rich and possesses unique A-type interflavan linkages in addition to the more common B-type interflavan bonds. Thus, PT is converted into oligomeric proanthocyanidins by depolymerization strategies, including the nucleophilic substitution reaction, acid hydrolysis, and hydrogenolysis. In addition, multiple health benefits exerted by PT mainly involve the inactivation of lipogenic and intracellular inflammatory signaling pathways, activation of the fatty acid oxidation signaling pathway, regulation of gut microbiota, and highly absorptive properties.

GSP-2, a polysaccharide extracted from Ganoderma sinense, is a novel toll-like receptor 4 agonist.

Ganoderma sinense is a Chinese unique medicinal fungus that has been used in folk medicine for thousands of years. Polysaccharides are considered to be biologically active ingredients due to their immune-modulating functions. Previously we found that GSP-2, a new polysaccharide isolated from Ganoderma sinense, exerts an immunomodulatory effect in human peripheral blood mononuclear cells but the underlying mechanism is unclear. The present study aimed to investigate how GSP-2 triggers immunologic responses and the implicated signaling pathways. GSP-2 effects were investigated both in a macrophagic cell line, RAW264.7, and in primary macrophages. Moreover, the molecular basis of GSP-2 recognition by immune cells, and the consequent activation of signaling cascades, were explored by employing recombinant human HEK293-TLR-Blue clones, individually overexpressing various Toll-like receptors. GSP-2 dose-dependently induced the overexpression of Toll-like receptor 4 (TLR4) but did not affect the expression of other TLRs. Moreover, GSP-2 induced TNFα secretion in primary macrophages from wild-type, but not TLR4-knockout mice. In addition, GSP-2 upregulated TLR4 protein expression and activated the MAPK pathway in RAW246.7 macrophages. Finally, GSP-2 induced the production of the cytokines TNFα, IL1ß, and IL6. Our data demonstrated that GSP-2 was specifically recognized by TLR4, promoting cytokine secretion and immune modulation in macrophages.

Shepherd's Purse Polyphenols Exert Its Anti-Inflammatory and Antioxidative Effects Associated with Suppressing MAPK and NF-κB Pathways and Heme Oxygenase-1 Activation.

Shepherd's purse (Capsella bursa-pastoris (L.) Medik.), a wild herb as a traditional herbal medicine, has been proved with multiple healthy benefits. In this study, the chemical constituents of shepherd's purse were identified by UPLC-QTOF-MS/MS. The antioxidative and anti-inflammatory potential of shepherd's purse extract (SPE) were also investigated applying lipopolysaccharide- (LPS-) induced inflammation in RAW 264.7 macrophages and a carrageenan-induced mice paw edema model. Twenty-four chemical compounds were identified mainly including phenolic acids and flavonoids. The data also indicated SPE inhibited the productions of NO, PGE2, TNF-α, and IL-6 stimulated with LPS. In addition, SPE inhibited the increase of reactive oxygen species (ROS) and upregulated the expression of heme oxygenase-1 (HO-1). We further found that SPE inhibited the phosphorylation of P38 MAPK and activation of NF-κB. In vivo mice model also indicated that SPE showed strong antioxidative and anti-inflammatory activity.

Inhibitory effect of different Dendrobium species on LPS-induced inflammation in macrophages via suppression of MAPK pathways.

Dendrobii Caulis (DC), named 'Shihu' in Chinese, is a precious herb in traditional Chinese medicine. It is widely used to nourish stomach, enhance body fluid production, tonify "Yin" and reduce heat. More than thirty Dendrobium species are used as folk medicine. Some compounds from DC exhibit inhibitory effects on macrophage inflammation. In the present study, we compared the anti-inflammatory effects among eight Dendrobium species. The results provided evidences to support Dendrobium as folk medicine, which exerted its medicinal function partially by its inhibitory effects on inflammation. To investigate the anti-inflammatory effect of Dendrobium species, mouse macrophage cell line RAW264.7 was activated by lipopolysaccharide. The nitric oxide (NO) level was measured using Griess reagent while the pro-inflammatory cytokines were tested by ELISA. The protein expressions of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2) and mitogen-activated protein kinases (MAPKs) phosphorylation were evaluated by Western blotting analysis. Among the eight Dendrobium species, both water extracts of D. thyrsiflorum B.S.Williams (DTW) and D. chrysotoxum Lindl (DCHW) showed most significant inhibitory effects on NO production in a concentration-dependent manner. DTW also significantly reduced TNF-α, MCP-1, and IL-6 production. Further investigations showed that DTW suppressed iNOS and COX-2 expression as well as ERK and JNK phosphorylation, suggesting that the inhibitory effects of DTW on LPS-induced macrophage inflammation was through the suppression of MAPK pathways. In conclusion, D. thyrsiflorum B.S.Williams was demonstrated to have potential to be used as alternative or adjuvant therapy for inflammation.

Persimmon Tannin Decreased the Glycemic Response through Decreasing the Digestibility of Starch and Inhibiting α-Amylase, α-Glucosidase, and Intestinal Glucose Uptake.

Regulation of postprandial blood glucose levels is an effective therapeutic proposal for type 2 diabetes treatment. In this study, the effect of persimmon tannin on starch digestion with different amylose levels was investigated both in vitro and in vivo. Oral administration of persimmon tannin-starch complexes significantly suppressed the increase of blood glucose levels and the area under the curve (AUC) in a dose-dependent manner compared with starch treatment alone in an in vivo rat model. Further study proved that persimmon tannin could not only interact with starch directly but also inhibit α-amylase and α-glucosidase strongly, with IC50 values of 0.35 and 0.24 mg/mL, separately. In addition, 20 µg/mL of persimmon tannin significantly decreased glucose uptake and transport in Caco-2 cells model. Overall, our data suggested that persimmon tannin may alleviate postprandial hyperglycemia through limiting the digestion of starch as well as inhibiting the uptake and transport of glucose.

Reshaped fecal gut microbiota composition by the intake of high molecular weight persimmon tannin in normal and high-cholesterol diet-fed rats.

It has been proposed that the gut microbiome may be related to obesity, and diet-induced obesity may induce changes in the gut microbiota composition. Our previous studies suggested that persimmon tannin (PT), which is highly polymerized and non-absorbable in the intestine, showed anti-hyperlipidemic and cholesterol-lowering effects in animal models. Considering that the possible composition modification effects of PT on intestinal bacteria might contribute to its anti-hyperlipidemic and cholesterol-lowering effects in vivo, in this study, we determined whether the PT administration could modify the gut microbiota in both normal diet-fed and high-cholesterol (HC) diet-fed rats, and how PT altered the bacterial composition in both normal and HC fed rats. Sprague-Dawley rats were randomly divided into eight groups, and fed with either a normal or an HC diet supplemented with or without a low/medium/high dose of PT (50 (LPT), 100 (MPT), 200 (HPT) mg per kg body weight (BW) per day, respectively) for 4 weeks. On days 0, 7, 14, 21 and 28, feces were collected and prepared for the microbiota and physicochemical analysis. The results showed that LPT and MPT supplementation significantly altered the gut microbiota composition by increasing the Bacteroidetes/Proteobacteria ratio in both normal diet-fed and HC diet-fed rats. LPT also decreased the Firmicutes/Bacteroidetes ratio in normal diet-fed rats and MPT decreased the Firmicutes/Bacteroidetes ratio in HC diet-fed rats. Both LPT and MPT supplementation induced a significant alteration in specific bacterial species after 14 days of treatment. The relative abundance of Bifidobacterium sp. and Lactobacillus sp. was increased by both LPT and MPT treatment, and that of Escherichia coli and Enterococcus was reduced. Our data also indicate that there is a correlation between the changes in bacterial composition and the changes in short-chain fatty acid (SCFA) metabolism. However, HPT supplementation altered the gut microbiota at the phylum and species levels in an adverse way.

Separation and purification of four phenolic compounds from persimmon by high-speed counter-current chromatography.

An efficient method was established by high-speed counter-current chromatography (HSCCC) for preparation of four phenolic compounds from the depolymerization products of persimmon tannin. Using the two solvent systems of n-hexane/ethyl acetate/water (3:17:20, v/v/v) and ethyl acetate/methanol/water (50:1:50, v/v/v), the preparative isolation was successfully performed by a two-step separation. The yields of one run (150mg crude sample) for gallic acid, methyl gallate, and epigallocatechin-3-gallate-(4ß→8, 2ß→O→7)-epigallocatechin-3-gallate dimer (A-type EGCG dimer) were 4.7, 44.2 and 5.9mg, respectively. In addition, 4.6mg epicatechin-3-gallate-(4ß→8, 2ß→O→7)-epicatechin-3-gallate dimer (A-type ECG dimer) was obtained by further preparative high-performance liquid chromatography (prep-HPLC). The purities of these compounds were all above 95.0% and their structures were identified by HPLC/ESI-MS. We found that HSCCC had definite advantages for the preparation of dimeric procyanidins compared with previous methods. Furthermore, it was shown that the four phenolic compounds possessed greater antioxidant activities than Trolox.

A traditional Chinese formula composed of Chuanxiong Rhizoma and Gastrodiae Rhizoma (Da Chuanxiong Formula) suppresses inflammatory response in LPS -induced RAW 264.7 cells through inhibition of NF-κB pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Da Chuanxiong Formula (DCXF) which origins from Jin Dynasty is a famous classical 2-herb Chinese medicinal prescription. It is composed of dried rhizomes of Ligusticum chuanxiong (Chuanxiong Rhizoma, CR) and Gastrodia elata (Gastrodiae Rhizoma, GR) at the ratio of 4:1 (w/w). It has been used to treat headache which is caused by wind pathogen and blood stasis for thousands of years in China. AIM OF STUDY: The present study was performed to investigate the anti-inflammatory effect of DCXF and elucidate its underlying molecular mechanisms using LPS-stimulated RAW 264.7 cells. MATERIALS AND METHODS: The anti-inflammatory effect of DCXF was evaluated using LPS-stimulated RAW 264.7 cells. Generation of nitric oxide (NO) and prostaglandin E2 (PGE2) were measured by the Griess colorimetric method and enzyme-linked immunosorbent assay (ELISA), respectively. The gene expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were detected by reverse transcription-polymerase chain reaction (RT-PCR). Furthermore, the effect of DCXF on NF-κB activation was measured by western blot assay. RESULTS: Treatment with DCXF significantly suppressed the productions of NO and PGE2 through inhibitions of iNOS and COX-2 expressions in LPS-stimulated RAW 264.7 cells. DCXF significantly decreased IκBα phosphorylation, inhibited p65 expression and reduced p-p65 level. These results suggested the anti-inflammatory effect of DCXF was associated with the reduction of inflammatory mediators through inhibition of NF-κB pathway. CONCLUSIONS: These results indicated that DCXF inhibited inflammation in LPS-stimulated RAW 264.7 cells through inactivation of NF-κB pathway.

Preparative separation of gallocatechin gallate from Camellia ptilophylla using macroporous resins followed by sephadex LH-20 column chromatography.

Gallocatechin gallate (GCG) possesses multiple potential biological activities. However, the content of GCG in traditional green tea is too low which limits its in-depth pharmacological research and application. In the present study, a simple, efficient and environment-friendly chromatographic separation method was developed for preparative enrichment and separation of GCG from cocoa tea (Camellia ptilophylla) which contains high content of GCG. In the first step, the adsorption properties of selected resins were evaluated, and XAD-7HP resin was chosen by its adsorption and desorption properties for GCG. In order to maximize column efficiency for GCG collection, the operating parameters (e.g., flow rate, ethanol concentration, and bed height) were optimized. We found that the best combination was the feed concentration at 20mg/mL, flow rate at 0.75 BV/h and the ratio of diameter to bed heights as 1:12. Under these conditions, the purity of GCG was 45% with a recovery of 89%. In order to obtain pure target, a second step was established using column chromatography with sephadex LH-20 gel and 55% ethanol-water solution as eluent. After this step, the purity of the GCG was 91% with a recovery of 68% finally.

Green tea polyphenols decreases uric acid level through xanthine oxidase and renal urate transporters in hyperuricemic mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Green tea is a Chinese materia medica with the main functions of "inducing urination and quenching thirst". Green tea polyphenols (GTP) are generally acknowledged as the main active fraction with multiple pharmacological functions in green tea. However, the effect of GTP on hyperuricemia is not clear till now. AIM OF STUDY: The present study was carried out to investigate the effect of GTP on serum level of uric acid in potassium oxonate (PO)-induced hyperuricemic mice, and explore the underlying mechanisms from two aspects of production and excretion of uric acid. MATERIALS AND METHODS: PO and GTP were intragastricly administered to mice for consecutive 7 days. Serum level of uric acid, and xanthine oxidase (XOD) activity in serum and liver were examined. Simultaneously, expression of XOD protein in liver was analyzed by Western blot assay. Expressions of urate transporters including urate-anion transporter (URAT) 1, organic anion transporter (OAT) 1 and 3 in kidney were analyzed by immunohistochemistry staining method. RESULTS: 300 and 600 mg/kg GTP significantly decreased serum level of uric acid of hyperuricemic mice in a dose-dependent manner (p<0.05 or p<0.01). Besides, 300 and 600 mg/kg GTP markedly reduced XOD activity in serum and liver of hyperuricemic mice (both p<0.01). Furthermore, 300 and 600 mg/kg GTP clearly reduced XOD expression in liver, as well as reduced URAT1 expression and increased OAT1 and OAT3 expressions in kidney of hyperuricemic mice (p<0.05 or p<0.01). CONCLUSIONS: These results demonstrated that GTP had the effect of lowering uric acid through decreasing the uric acid production and increasing uric acid excretion. Our study suggested that GTP would be a promising candidate as a novel hypouricaemic agent for further investigation.

Er-Miao-San, a traditional herbal formula containing Rhizoma Atractylodis and Cortex Phellodendri inhibits inflammatory mediators in LPS-stimulated RAW264.7 macrophages through inhibition of NF-κB pathway and MAPKs activation.

ETHNOPHARMACOLOGICAL RELEVANCE: Er-Miao-San (EMS) is a traditional Chinese herbal formulation that contains combinations of Rhizoma Atractylodis (RA) and Cortex Phellodendri (CP). It exhibits analgesic and anti-inflammatory activities and have been used for the treatment of various "Bi Zheng" for thousand years in China. The aims of the present study were to investigate the anti-inflammatory activities of EMS and elucidate the underlying mechanisms with regard to its molecular basis of action for the best combination. MATERIALS AND METHODS: The anti-inflammatory effects of EMS were studied by using lipopolysaccharide (LPS)-stimulated activation of nitric oxide (NO) and pro-inflammatory cytokine production in mouse RAW264.7 macrophages. Expression of inducible NO synthase (iNOS), mitogen-activated protein kinases (MAPKs) phosphorylation, p65 phosphorylation, inhibitor-κBα (IκBα) degradation, and NF-κB DNA-binding activity were further investigated. RESULTS: The present study demonstrated that EMS could suppress the production of NO in LPS-stimulated RAW264.7 macrophages. However, CP and RA did not have significant inhibitory effect on them. EMS also inhibited the production of tumor necrosis factor-alpha, interleukin-1 beta and macrophage chemotactic protein-1. Further investigations showed EMS could suppress iNOs expression and p38 phosphorylation. EMS significantly decreased the content of IκBα, reduced the level of phosphorylated p65 and suppressed the NF-κB DNA-binding activity. All these results suggested the inhibitory effects of EMS on the production of inflammatory mediators through the inhibition of the NF-κB pathway. CONCLUSIONS: Our results indicated that EMS inhibited inflammatory events and iNOS expression in LPS-stimulated RAW264.7 cells through the inactivation of the MAPK and NF-κB pathway. This study gives scientific evidence validating the use of EMS in treatment of patients with "Bi Zheng" in clinical practice in traditional Chinese medicine.

Green tea (Camellia sinensis) extract inhibits both the metastasis and osteolytic components of mammary cancer 4T1 lesions in mice.

Green tea (Camellia sinensis, CS), a kind of Chinese tea commonly consumed as a healthy beverage, has been demonstrated to have various biological activities, including antioxidation, antiobesity and anticancer. Our study aims to investigate the antitumor, antimetastasis and antiosteolytic effects of CS aqueous extract both in vitro and in vivo using metastasis-specific mouse mammary carcinoma 4T1 cells. Our results showed that treatment of 4T1 cells with CS aqueous extract resulted in significant inhibition of 4T1 cell proliferation. CS extract induced 4T1 apoptosis in a dose-dependent manner as assessed by annexin-V and propidium iodide staining and caspase-3 activity. Western blot analysis showed that CS increased the expression of Bax-to-Bcl-2 ratio and activated caspase-8 and caspase-3 to induce apoptosis. CS also inhibited 4T1 cell migration and invasion at 0.06-0.125 mg/ml. In addition, CS extract (0.6 g/kg, orally fed daily for 4 weeks) was effective in decreasing the tumor weight by 34.8% in female BALB/c mice against water treatment control (100%). Apart from the antitumor effect, CS extract significantly decreased lung and liver metastasis in BALB/c mice bearing 4T1 tumors by 54.5% and 72.6%, respectively. Furthermore, micro-computed tomography and in vitro osteoclast staining analysis suggested that CS extract was effective in bone protection against breast cancer-induced bone destruction. In conclusion, the present study demonstrated that the CS aqueous extract, which closely mimics green tea beverage, has potent antitumor and antimetastasis effects in breast cancer and could protect the bone from breast cancer-induced bone destruction.