Oregonin

Positive effect of natural antioxidant oregonin from Alnus incana bark on ram semen quality stored at 5 degrees C for 48 h.[Pubmed:32387554]

Res Vet Sci. 2020 Aug;131:153-158.

The maintenance of high vitality and motility of ram's spermatozoa during storage at low temperatures has a crucial role for successful fertilization. This study evaluates the effect of the natural antioxidant Oregonin on ram semen quality, stored at 5 degrees C for 48 h. capital IE, Cyrillicighteen ejaculates (three repetitions for 6 ejaculates) from three local breed rams, collecting by artificial vagina, with volume > 1 ml, concentration > 1 x 10(9)/ml and mass motility >3.5 were used for chilling. Each ejaculate was separated in two equal parts, diluted with Tris-glucose-glycerol-egg yolk extender with no Oregonin or supplemented with 100mucapital EM, Cyrillic Oregonin until adjustment of the sperm concentration to 200 x 10(6) cells/ml and stored at 5 degrees C for 48 h. The semen quality assessment was based on the main kinematic (by CASA analysis), morphological parameters (by BrightVit kit staining) and mitochondrial status (by MitoView staining) of the spermatozoa on 0, 24 and 48 h of storage, and on in vivo fertility test. Oregonin did not impair the morphology and kept sustained motility of ram spermatozoa stored at 5 degrees C for 48 h. The curvilinear velocity indicated faster movement of the Oregonin treated sperms that corresponded with high percent of spermatozoa with active mitochondria in these samples. The fertilizing capacity of spermatozoa was preserved and pregnancy rate in the experimental group was 80% versus 60% in control. In conclusion, this study provides a new data about positive effect of the natural antioxidant Oregonin, supplemented to the extender, on chilled ram semen quality, including fertilizing ability.

Oregonin from Alnus incana bark affects DNA methyltransferases expression and mitochondrial DNA copies in mouse embryonic fibroblasts.[Pubmed:29877148]

J Enzyme Inhib Med Chem. 2018 Dec;33(1):1055-1063.

Oregonin is an open-chain diarylheptanoid isolated from Alnus incana bark that possesses remarkable antioxidant and anti-inflammatory properties, inhibits adipogenesis, and can be used in the prevention of obesity and related metabolic disorders. Here, we aimed to investigate the effects of Oregonin on the epigenetic regulation in cells as well as its ability to modulate DNA methylating enzymes expression and mitochondrial DNA (mtDNA) copies. Our results show that Oregonin altered the expression of DNA methyltransferases and mtDNA copy numbers in dependency on concentration and specificity of cells genotype. A close correlation between mtDNA copy numbers and mRNA expression of the mtDnmt1 and Dnmt3b was established. Moreover, molecular modeling suggested that Oregonin fits the catalytic site of DNMT1 and partially overlaps with binding of the cofactor. These findings further extend the knowledge on Oregonin, and elucidate for the first time its potential to affect the key players of the DNA methylation process, namely DNMTs transcripts and mtDNA.

Oregonin inhibits inflammation and protects against barrier disruption in intestinal epithelial cells.[Pubmed:29655054]

Int Immunopharmacol. 2018 Jun;59:134-140.

BACKGROUND AND AIMS: Oregonin, a major diarylheptanoid derivative isolated from Alnus japonica, exerts anti-inflammatory effects; however, little is known about the effect of Oregonin in intestinal inflammation. The current study investigated the potential of Oregonin for clinical applications in the treatment of inflammatory bowel disease (IBD) and elucidated its underlying molecular mechanisms. METHODS: The anti-inflammatory effect of Oregonin in tumor necrosis factor-alpha (TNF-alpha)-stimulated human intestinal epithelial HT-29 cells was investigated. In addition, the protective effect of Oregonin was determined against disruption of the intestinal barrier in tert-butyl hydroperoxide (t-BH)-stimulated human intestinal epithelial Caco-2 cells. RESULTS: Oregonin suppressed the expression of cyclooxygenase-2 (COX-2), intercellular adhesion molecule-1 (ICAM-1), IL-8, and IL-1beta, and inhibited activation of nuclear factor kappaB (NF-kappaB) in HT-29 cells stimulated with TNF-alpha. Oregonin increased heme oxygenase-1 (HO-1) expression through the ERK1/2 and JNK-dependent signaling pathway, which contributed to the Oregonin-mediated suppression of COX-2 expression in the HT-29 cells stimulated with TNF-alpha. Moreover, Oregonin induced AMP-activated protein kinase (AMPK) activation. Knockdown of AMPK abolished the induction of HO-1 protein by Oregonin and suppression of Oregonin-mediated ICAM-1 and COX-2 expression in the HT-29 cells stimulated with TNF-alpha. Oregonin prevented the t-BH-induced increase in monolayer permeability through inhibition of the reduction in expression of zonula occludens-1 and occludin in Caco-2 cells. Targeting HO-1 by siRNA transfection attenuated the Oregonin-mediated prevention of loss of tight junction proteins and increase in permeability. CONCLUSION: The findings of this study suggest that Oregonin is a potential candidate for treatment of IBD by preventing mucosal inflammation and barrier disruption.

Bioactivity-guided identification of antimicrobial metabolites in Alnus glutinosa bark and optimization of oregonin purification by Centrifugal Partition Chromatography.[Pubmed:27428455]

J Chromatogr B Analyt Technol Biomed Life Sci. 2016 Sep 1;1029-1030:121-127.

Barks from conifers and broadleaved trees constitute abundant wastes generated from wood harvesting and logging activities. Extracts of such residues obtained from Alnus trees have been reported as interesting resources with potent antibacterial activities. The present study aims to determine the antimicrobial activity of a crude methanol extract prepared from the bark of Alnus glutinosa against a panel of 22 bacteria and yeasts and to optimize a purification method enabling the high production of the most active substances. Fractionation of the crude extract was performed by Centrifugal Partition Chromatography (CPC) using a three-phase solvent system composed of n-heptane, methyl-ter-butyl ether, acetonitrile and water. The major known compounds contained in the fractions produced by CPC were chemically profiled by (13)C NMR dereplication, resulting in the unambiguous identification of Oregonin, hirsutanonol, betulinic acid, and alusenone 1a. The antibacterial evaluation of the fractions by bioautography on Staphylococcus aureus revealed that Oregonin, in addition to being the major metabolite of the crude extract ( approximately 32% w/w), was the most active with an antibacterial inhibitory effect comparable to antibiotics. The purification of Oregonin was optimized at the laboratory-scale by CPC. A single injection of 3.7g of crude extract resulted in a recovery of 72% (850mg) of the available Oregonin at purity higher than 94%.

Two new phenolic compounds from the leaves of Alnus sibirica Fisch. ex Turcz.[Pubmed:26211877]

Nat Prod Res. 2016;30(2):206-13.

Two new phenolic compounds, 4-O-glucopyranosyl-5-O-caffeoylshikimic acid (1) and 2,3-digalloyl Oregonin (2), were isolated along with eight known phenolic compounds (3-10) from an 80% acetone extract of Alnus sibirica leaves. The chemical structures of these compounds were elucidated using 1D/2D nuclear magnetic resonance and high resolution-MS. The anti-oxidative activities of these compounds were determined by assaying their 1,1-diphenyl-2-picrylhydrazyl radical and nitroblue tetrazolium superoxide anion scavenging activity. All of the isolated phenolic compounds (1-10) exhibited potent anti-oxidative activities. In particular, 2 and 4, which are diarylheptanoids, and 10 which is ellagitannin exhibited excellent anti-oxidative activities with almost the same potency as that of the positive controls L-ascorbic acid and allopurinol.

Antiproliferative and Pro-Apoptotic Activity of Diarylheptanoids Isolated from the Bark of Alnus japonica in Human Leukemia Cell Lines.[Pubmed:26119959]

Am J Chin Med. 2015;43(4):757-67.

Alnus japonica Steud is a tree that grows in damp areas of mountain valleys and has been used as a traditional medicine in Asia. We investigated the antiproliferative activity of hirsutanone (Hir) and Oregonin (Ore) in human cancer cell lines and elucidated their mechanisms of action. A cytotoxicity study using a panel of 12 human cancer and 4 normal cell lines indicated that Hir exhibited potent antiproliferative activity against 4 leukemia (Jurkat, U937, THP-1, and HL-60) and 2 colon cancer cell lines (HCT-15 and Colo205). Although Ore suppressed the cell growth of Jurkat and THP-1, its inhibitory potency was weaker than that of Hir. The IC50 values of Hir and Ore in Jurkat were 11.37 muM and 22.16 muM, respectively. Further analysis on Jurkat cells demonstrated that Hir caused a sequence of events involved in apoptosis, including nuclear morphological changes and accumulation of cells with sub-G1 DNA content. Hir led to the cleavage of poly(ADP-ribose) polymerase (PARP) and activation of caspase-3, -8, and -9. In addition, Hir-induced PARP cleavage was completely abolished by specific inhibitors to these caspases. Our data suggested that Hir is a potent antiproliferative compound against the 4 leukemia cell lines and the 2 colon cancer cell lines tested. Furthermore, Hir exerts antiproliferative actions via caspase-dependent apoptotic cell death.

New anti-trypanosomal active tetracyclic iridoid isolated from Morinda lucida Benth.[Pubmed:26048790]

Bioorg Med Chem Lett. 2015 Aug 1;25(15):3030-3.

Human African trypanosomiasis (HAT), commonly known as sleeping sickness has remained a serious health problem in many African countries with thousands of new infected cases annually. Chemotherapy, which is the main form of control against HAT has been characterized lately by the viewpoints of toxicity and drug resistance issues. Recently, there have been a lot of emphases on the use of medicinal plants world-wide. Morinda lucida Benth. is one of the most popular medicinal plants widely distributed in Africa and several groups have reported on its anti-protozoa activities. In this study, we have isolated one novel tetracyclic iridoid, named as molucidin, from the CHCl3 fraction of the M. lucida leaves by bioassay-guided fractionation and purification. Molucidin was structurally elucidated by (1)H and (13)C NMR including HMQC, HMBC, H-H COSY and NOESY resulting in tetracyclic iridoid skeleton, and its absolute configuration was determined. We have further demonstrated that molucidin presented a strong anti-trypanosomal activity, indicating an IC50 value of 1.27 muM. The cytotoxicity study using human normal and cancer cell lines indicated that molucidin exhibited selectivity index (SI) against two normal fibroblasts greater than 4.73. Furthermore, structure-activity relationship (SAR) study was undertaken with molucidin and Oregonin, which is identical to anti-trypanosomal active components of Alnus japonica. Overlapping analysis of the lowest energy conformation of molucidin with Oregonin suggested a certain similarities of aromatic rings of both Oregonin and molucidin. These results contribute to the future drug design studies for HAT.

Oregonin reduces lipid accumulation and proinflammatory responses in primary human macrophages.[Pubmed:25686497]

Biochem Biophys Res Commun. 2015 Mar 13;458(3):693-699.

Inflammation in the vascular wall is important for the development of atherosclerosis. We have previously shown that inflammatory macrophages are more abundant in human atherosclerotic lesions than in healthy arteries. Activated macrophages produce reactive oxygen species (ROS) that promote local inflammation in atherosclerotic lesions. Here, we investigated the role of Oregonin, a diarylheptanoid, on proinflammatory responses in primary human macrophages and found that Oregonin decreased cellular lipid accumulation and proinflammatory cytokine secretion. We also found that Oregonin decreased ROS production in macrophages. Additionally, we observed that treatment of lipopolysaccharide-exposed macrophages with Oregonin significantly induced the expression of antioxidant-related genes, including Heme oxygenase-1 and NADPH dehydrogenase quinone 1. In summary, we have shown that Oregonin reduces lipid accumulation, inflammation and ROS production in primary human macrophages, indicating that Oregonin has anti-inflammatory bioactivities.

First characterisation of flavonoid- and diarylheptanoid-type antioxidant phenolics in Corylus maxima by HPLC-DAD-ESI-MS.[Pubmed:25594894]

J Pharm Biomed Anal. 2015 Mar 25;107:159-67.

Corylus maxima Mill. (Betulaceae) leaves have been used in traditional medicine both internally and externally, nevertheless phytochemical exploration of the plant remains incomplete. In this study, the in vitro antioxidant activity and polyphenolic composition of the ethyl acetate and methanolic extracts of C. maxima leaves and bark are reported for the first time. The radical scavenging activities of the extracts were investigated by the ABTS and DPPH assays. All the extracts of C. maxima possessed notable antioxidant activity. By mean of a HPLC-DAD-ESI-TOF and a HPLC-DAD-ESI-MS/MS method, altogether twenty-two phenolics were tentatively characterised: one flavan derivative (1), seven flavonol derivatives (4, 6, 12, 13, 16, 20 and 21) and fourteen diarylheptanoids (2, 3, 5, 7-11, 14, 15, 17-19 and 22). The amount of the two main flavonoids - myricetin-3-O-rhamnoside (6) and quercetin-3-O-rhamnoside (13) - and two diarylheptanoids - Oregonin (3) and hirsutenone (15) - in the extracts were determined by a validated HPLC-ESI-MS/MS method in multiple reaction monitoring (MRM) mode. Our results showed that C. maxima could be considered as a valuable source of pharmacologically important natural products that might contribute to the revaluation of the phytotherapeutical potential of the plant.

Anti-trypanosomal activity of diarylheptanoids isolated from the bark of Alnus japonica.[Pubmed:25178281]

Am J Chin Med. 2014;42(5):1245-60.

The crude extract of Alnus japonica bark exhibited a strong effect on the growth of Trypanosoma brucei. Subsequent chromatographic separation resulted in the isolation of two novel diarylheptanoids, known as alnuside C (2) and alnuside D (3), and three known compounds, 1-(3,4-dihydroxyphenyl)-7-(4-hydroxyphenyl)-heptan-3(R)-O-beta-D-glucopyranoside (1), Oregonin (4) and hirsutanone (5). The structures of the isolates were elucidated based on the use of extensive spectroscopic and chemical methods. Among the isolated diarylheptanoids, Oregonin (4) (a major component of plant bark) and hirsutanone (5) exhibited potent in vitro inhibitory activity against T. brucei growth in the bloodstream with IC50 values of 1.14 and 1.78 muM, respectively. We confirmed that Oregonin (4) and hirsutanone (5) were not toxic to human normal skin fibroblast cells (NB1RGB) and colon cancer cells (HCT-15) at a concentration of 50 muM; however, lower levels of toxicity were observed for leukemia cells. To determine the structure activity relationships of the isolated components, we performed Conformation Search and found that the 3-oxo function of the heptane chain in the diarylheptanoid molecule is required for their trypanocidal activity.

Alnuheptanoid A: a new diarylheptanoid derivative from Alnus japonica.[Pubmed:25116915]

Nat Prod Res. 2014;28(20):1765-71.

Extensive chromatographic investigation of the ethanolic extract of Alnus japonica Steud stem bark led to the isolation of a new diarylheptanoid named alnuheptanoid A [(5S)-7-(3,4-dihydroxyphenyl)-1-(4-hydroxyphenyl)-5-methoxyheptan-3-one] (8), together with seven known diarylheptanoid derivatives: platyphyllenone (5), (5S)-1,7-bis(4-hydroxyphenyl)-5-methoxyheptan-3-one (6), 1-(3,4-dihydroxyphenyl)-7-(4-hydroxyphenyl)-4-hepten-3-one (7), hirsutenone (9), (5R)-O-methylhirsutanonol (10), hirsutanonol (11) and Oregonin (13), three triterpenes: alpha-amyrin (1), betulinaldehyde (3) and betulinic acid (4), and two sterols: beta-sitosterol (2) and daucosterol (12). Compound 6 was isolated for the first time from natural source. The structures of the isolated compounds were determined on the basis of spectroscopic measurements (UV, IR, HR-ESI-MS, 1D and 2D NMR).

Oregonin from the Bark of Alnus japonica restrained ischemia-reperfusion-induced mesentery oxidative stress by inhibiting NADPH oxidase activation.[Pubmed:24852886]

Microcirculation. 2014 Nov;21(8):688-95.

OBJECTIVE: NADPH oxidase activation results in ROS overproduction that is the pathological basis of I/R injury. This study aimed to investigate potential effects of ORG on I/R-induced ROS production in rat mesenteric microvasculature and underlying mechanisms. METHODS: Mesenteric I/R in Male Wistar rats (200~250 g) was induced by ligation of the mesenteric artery and vein for 10 minutes followed by reperfusion for 60 minutes by releasing of the occlusion. The rats were infused intravenously with or without ORG (5 mg/kg per hour) 10 minutes before ischemia (pretreatment) or 20 minutes after reperfusion (posttreatment). The DHR fluorescence intensity on, the leukocytes adherent to, and mast cell degranulation out of mesenteric venules were determined using an intravital microscope. NADPH oxidase subunit p47(phox) membrane translocation in intestine tissues was detected by Western blotting. RESULTS: Pre- or posttreatment with ORG inhibited I/R-induced DHR fluorescence intensity on the venular walls and leukocytes adhesion, ORG pretreatment inhibited mast cell degranulation as well. Furthermore, the translocation of p47(phox) from cytosol to membrane was suppressed markedly by ORG after I/R. CONCLUSIONS: The results suggested that ORG restrained I/R-induced ROS production, which might be correlated with its inhibitive effect on NADPH activation.

Elucidation of antioxidant properties of wood bark derived saturated diarylheptanoids: a comprehensive (DFT-supported) understanding.[Pubmed:24703933]

Phytochemistry. 2014 Jul;103:178-187.

A series of diarylheptanoids, namely 1,7-bis-(3,4-dihydroxyphenyl)-heptan-3-one-5-O-D-xylopyranoside (Oregonin), 1,7-bis-(3,4-dihydroxyphenyl)-3-hydroxyheptane-5-O-beta-D-xylopyranoside and 1,7-bis-(4-hydroxyphenyl)-heptane-3-one-5-O-beta-D-glucopyranoside (platyphylloside), were isolated from the bark of alder family trees, a species widely spread over in Europe. As antioxidants, these natural polyphenols have a promising potential in various fields of application, but their redox reactivity is insufficiently characterized. In this work, their antioxidant activity is described using assays based on DPPH and ABTS(+) radical scavenging, oxygen anion radicals (O2(-)) quenching. The standardized ORAC assay was also achieved, which measures the capacity to protect fluorescent molecules against oxidative degradation. The measured antioxidant activity was higher than that of the well-known antioxidant and biologically active diarylheptanoid curcumin. Molecular modeling was used to rationalize the differences in activity and the mechanisms of action. Thermodynamic descriptors mainly O-H bond dissociation enthalpies (BDEs) establish a clear structure-activity relationship.

Efficacy of oregonin investigated by non-invasive evaluation in a B16 mouse melanoma model.[Pubmed:24171727]

Exp Dermatol. 2013 Dec;22(12):842-4.

Oregonin has been reported to act as a mediator of antibiosis, a liver-protective agent, an antioxidant, an anti-inflammatory agent, and to prevent cancer outbreaks. B16 melanoma cells were separated with trypsin-ethylenediaminetetraacetic acid, resuspended in 50 mul of phosphate-buffered saline and transplanted into the backs of 6- to 8-week-old male Balb/c nude mice through subcutaneous injection. Treatment doses of Oregonin were administered three times weekly, for 30 days from the 11th day after transplantation of the melanoma cells, in each group. The study consisted of a control group, a dacarbazine group, an Oregonin group and a dacarbazine + Oregonin group. Measurements were taken before treatment and on the 5th, 7th, 10th and 15th days after treatment for each group. Based on survival rates after transplantation, the control group showed less than 50% survival after 20 days, while the treatment groups showed at least 50% survival up to the 41st day.