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Dry eye is one of the most common ocular surface diseases caused by tear film instability and ocular surface damage due to an abnormal quality or quantity of tears. Inflammatory factors can initiate relevant transduction signalling pathways and trigger the inflammatory cascade response, resulting in ocular surface inflammation. It has been shown that the active ingredients in Dendrobium, such as polysaccharides, alkaloids and phenols, have anti-inflammatory, anti-tumour and immunity-boosting effects, and Dendrobium officinale extract can improve glandular secretion function, increase salivary secretion and increase the expression level of water channel protein in salivary glands in patients with dry eye syndromes. We investigated the in vitro cytoprotective effect of Dendrobium extracts in sodium chloride induced hyperosmotic conditions in human cornea keratocytes (HKs). Results showed that Dendrobium officinale Kimura et Migo water extract (DOW) and Dendrobium loddigesii Rolfe water extract (DLW) could upregulate the expression of aquaporins (AQP)5 protein, thus exerting a repairing effect by promoting cell migration. Furthermore, oral administration of DOW and DLW enhanced tear production in rats and exerted a protective effect on ocular surface damage. DOW and DLW could upregulate the expression of AQP5 and mucin (muc)5ac proteins in the lacrimal gland and reduce the inflammatory response. DOW and DLW inhibited the activation of the corresponding mitogen-activated protein kinases (MAPK) and NF-KB pathway, thereby playing a role in improving dry eye symptoms. This study provides a new perspective on dry eye treatment, and DOW and DLW may be potential therapeutic agents for dry eye. [ABSTRACT FROM AUTHOR]

The cortex root of Paeonia ostii, is used as a traditional Chinese medicine for treating female diseases. Phytochemical investigation of the water-soluble fraction of the plant led to the isolation of two new acetoisovanillone glycosides: acetoisovanillone-3-O-β-D-glucopyranoside (1) and 2-hydroxy-acetoisovanillone-3-O-β-D-glucopyranoside (2). Their structures were elucidated by extensive spectroscopic methods. [ABSTRACT FROM AUTHOR]

Two new sesquiterpenoids, including a kessane-type sesquiterpenoid (1) and one bisabolane derivative (2), together with fourteen known sesquiterpenoids (3–16), were isolated from the roots and rhizomes of Valeriana amurensis. The structures of new compounds were established on the basis of extensive spectroscopic analysis. All isolates were evaluated for their effects on nerve growth factor (NGF)-mediated neurite outgrowth in pheochromocytoma (PC12) cells. As a results, four compounds including 10–12 and 15 showed potent promoting effects at the concentration of 10 µM on NGF-induced neurite outgrowth in PC12 cells with the differentiation rate of 11.84%, 12.21%, 13.77% and 12.16%, respectively. [ABSTRACT FROM AUTHOR]

Two new compounds (9 and 10) having a camptothecin (CPT) analog conjugated to the 4β-azido-4-deoxypodophyllotixin analog by untilizing the copper-catalyzed azide-alkyne cycloadditon (CuAAC) reaction, and were evaluated for their cytotoxicity against a panel of five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7 and SW480) using the MTT (3-(4,5-dimethyl-thiahiazo-2-yl)-2,5-diphenyltetrazolium bromide) assay. Two novel conjugates shown weak cytotoxicity, compound 10 showed highly potent against HL-60 cell line tested, with IC50 value 17.69 ± 0.19 μM. This compound suggested its potential as anticancer agents for further development. [ABSTRACT FROM AUTHOR]

α-mangostin, a polyphenol xanthone derivative, was mainly isolated from pericarps of the mangosteen fruit (Garcinia mangostana L.). In present investigation, a series of derivatives were designed, synthesised and evaluated in vitro for their inhibitory activity of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Among the synthesised xanthones, compounds 1, 9, 13 and 16 showed AChE selective inhibitory activity, 15 was a BuChE selective inhibitor while 2, 3, 5, 6, 7, 12 and 14 were dual inhibitors. The most potent inhibitor of AChE was 16 while 5 was the most potent inhibitor of BuChE with IC50 values of 5.26 μM and 7.55 μM respectively. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the ameliorative effect of Dendrobium officinale Kimura et Migo (DO) on a desiccated environment-induced experimental dry eye rat model and elucidate its underlying mechanisms. Materials and Methods: The Sprague-Dawley rats were kept in low-humidity environment and received constant airflow for 8 weeks to establish the experimental dry eye model. DO water extract (DOW, 372 mg/kg/day) was orally administered daily for 8 weeks. Schirmer's test was used to measure the tear fluid production at days 0, 14, 28, 42, and 56. At the end of experiment, lacrimal gland tissues and eyeballs were collected for hematoxylin and eosin staining, PAS staining, and immunohistochemical staining. Inflammatory cytokines in conjunctiva including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and matrix metalloproteinase 9 were measured by real-time PCR. The aquaporin 5 (AQP5) expression in lacrimal gland was also determined using Western blot assay. Results: DOW treatment (DOWT) increased the tear production of rats significantly in the desiccated environment at day 42. Histological analysis revealed that DOW could reverse destruction of conjunctiva and increase goblet cell number and mucin expression in the experimental dry eye rats. In dry eye rats, desiccated environment and constant airflow induced TNF-α and IL-1β production in the conjunctiva, whereas DOWT reversed the upregulation of proinflammatory cytokines. Moreover, DOWT increased the expression of AQP5 at protein level in the lacrimal gland tissues in both desiccated and normal environmental conditions. Conclusion: The present study suggests that DO has therapeutic potential on dry eye symptoms through upregulating AQP5 expression, increasing tear production, inhibiting conjunctiva destruction and inflammation, as well as promoting mucin production. [ABSTRACT FROM AUTHOR]

Four new monoterpenoids, including two new acyclic monoterpenoids (2R, 6R)-2, 6-dimethyl-8-isovaleroxyoctan-1-ol (1) and (2S, 6S)-2, 6-dimethyl-8-isovaleroxyoctan-1-ol (2), as well as two new iridoids stenopterins F-G (3 and 4), together with fifteen known compounds (5–19), were isolated from whole dried material of Valeriana stenoptera. Stenopterin F was the first reported iridoids with n-butoxyl in the Valerianaceae family. The structures of new compounds were established on the basis of extensive spectroscopic analysis. [ABSTRACT FROM AUTHOR]

A new steroid lactone aspergilolide (1), and nine known compounds helvolic acid (2), verruculogen (3), tryprostatin B (4), 13-oxofumitremorgin B (5), fumitremorgin C (6), demethoxy fumitremorgin C (7), terezine D (8), aszonalenin (9), 12, 13-dihydroxy-fumitremorgin C (10) from cultures of the endophytic fungus Aspergillus sp. MBL1612. Their chemical structures were determined by a series of extensive spectroscopic methods. All of the compounds were isolated from this genus for the first time. The cytotoxicity against five human cancer cell lines of new compound were detected. [ABSTRACT FROM AUTHOR]

Type 2 diabetes was usually caused by inadequate secretion of insulin or insulin resistance in tissues and organs. About 90% diabetes belongs to type 2 diabetes, which is seriously harmful to human health. Dipeptidyl Peptidase‐IV (DPP‐IV) target have attracted much attention because of its ability to prevent type 2 diabetes (T2D). Clinical application of chemical synthetic medicines has different degrees of side effects. Therefore, the present evaluation aims to seek DPP‐IV inhibitors as the source of natural products. DPP‐IV inhibitory activities of eight natural products and a structural modification of mangostin (eight chromone of 1–8 and iridoid glycoside for 9) were evaluated by this manuscript at the enzyme level. As a result, three chromones of 2 (a modified mangostin), 3 (mangiferin) and 5 (breviscapin) showed moderate DPP‐IV inhibitory activities with IC50 values of 69.27 μM, 44.19 μM, and 49.53 μM via the use of the fluorescence‐based method (0.25 mM, 0.34 mM and 0.85 mM for the chromogenic substrate method). This study suggests that natural products, which mainly consist by chromone that generated from Mango and Scutellaria baicalensis may have beneficial effects on treating T2D. Two natural products which derived from Mango and Scutellaria baicalensis showed inhibitory activities against DPP‐IV. A modified mangostin was also identified with inhibitory activity. The results indicated that these natural products can play prophylactic or therapeutic roles against T2D (type 2 diabetes) and provided structurally different skeletons to develop new drugs in the treatment of T2D. [ABSTRACT FROM AUTHOR]

Four new glucosides, named as gigantol-5-O-β-d-glucopyranoside (1), 9,10-dihydro-aphyllone A-5-O-β-d-glucopyranoside (2), ficusal-4-O-β-d-glucopyranoside (3), botrydiol-15-O-β-d-glucopyranoside (4), together with eight known compounds (5–12) were isolated from then-BuOH extract of the stems ofDendrobium fimbriatumHook. Their structures were elucidated by the analyses of spectroscopic data. [ABSTRACT FROM PUBLISHER]

Epigallocatechin gallate (EGCG) is the most abundant component of green tea catechins and has strong physiological activities. In this study, two novel EGCG glycosides (EGCG-G1 and EGCG-G2) were chemoselectively synthesized by a chemical modification strategy. Each of these EGCG glycosides underwent structure identification, and the structures were assigned as follows: epigallocatechin gallate-4″-O-β-D-glucopyranoside (EGCG-G1, 2) and epigallocatechin gallate-4′,4″-O-β-D-gluco-pyranoside (EGCG-G2, 3). The EGCG glycosides were evaluated for their anticancer activity in vitro against two human breast cell lines (MCF-7 and MDA-MB-231) using MTT assays. The inhibition rate of EGCG glycosides (EGCG-G1 and EGCG-G2) is not obvious. The EGCG glycosides are more stable than EGCG in aqueous solutions, but exhibited decreasing antioxidant activity in the DPPH radical-scavenging assay (EGCG > EGCG-G2 > EGCG-G1). Additionally, the EGCG glycosides exhibited increased water solubility: EGCG-G2 and EGCG-G1 were 15 and 31 times as soluble EGCG, respectively. The EGCG glycosides appear to be useful, and further studies regarding their biological activity are in progress. [ABSTRACT FROM AUTHOR]

Two new bibenzyl derivatives, dendrocandin T (1) and dendrocandin U (2), together with eight known bibenzyls, were isolated from the stems ofDendrobium officinale. Those compounds were sent for the first time for central nervous system-related bioassay and the results indicated that compounds3,4, and5have a certain degree of neurite outgrowth-promoting activity, and compounds1,2,6, and7also have weak activity. The results indicated thatD. officinaleused as health food and traditional Chinese medicine “Tiepi Shihu” has a health function of neurotrophic effects. [ABSTRACT FROM PUBLISHER]