Tiliroside

Fitoterapia. 2007 Jan;78(1):1-6.

Tiliroside and gnaphaliin inhibit human low density lipoprotein oxidation.[Pubmed: 17084992]

Two flavonoids, gnaphaliin and Tiliroside, isolated from Helichrysum italicum, were studied in vitro for their capacity to inhibit Cu(2+)-induced human low density lipoprotein (LDL) and diluted plasma oxidation.
METHODS AND RESULTS:
LDL oxidation was monitored by conjugated diene, thiobarbituric acid-reactive substances (TBARS) formation and electrophoretic mobility on agarose gel. Gnaphaliin and Tiliroside increased the lag-phase for diene conjugate production in a dose-dependent manner. The reduction of TBARS production confirmed the antioxidant activity of gnaphaliin and Tiliroside with 50% inhibitory concentration (IC(50)) values of 8.0+/-3.9 microM and 7.0+/-2.6 microM respectively. Furthermore, the flavonoids negated the Cu(2+)-induced increase in electrophoretic mobility of LDL. Antioxidant activity of gnaphaliin and Tiliroside was significantly different when diluted plasma was oxidised by adding 1 mM CuSO(4). Although both flavonoids again reduced the TBARS production, Tiliroside showed higher activity than gnaphaliin (IC(50)=10.6+/-2.5 microM vs. IC(50)>50 microM).
CONCLUSIONS:
In conclusion, Tiliroside and gnaphaliin are antioxidants against in vitro Cu(2+)-induced LDL oxidation in the same order of magnitude compared to that of the reference drug, probucol.

Eur J Pharmacol. 2003 Feb 7;461(1):53-61.

Assessment of the anti-inflammatory activity and free radical scavenger activity of tiliroside.[Pubmed: 12568916]

Three flavonoids, gnaphaliin, pinocembrin and Tiliroside, isolated from Helichrysum italicum, were studied in vitro for their antioxidant and/or scavenger properties and in vivo in different models of inflammation.
METHODS AND RESULTS:
In vitro tests included lipid peroxidation in rat liver microsomes, superoxide radical generation in the xanthine/xanthine oxidase system and the reduction of the stable radical 1,1-diphenyl-2-pycryl-hydrazyl (DPPH). Acute inflammation was induced by application of 12-O-tetradecanoylphorbol 13-acetate (TPA) to the mouse ear or by subcutaneous injection of phospholipase A(2) or serotonin in the mouse paw. Eczema provoked on the mouse ear by repeated administration of TPA was selected as a model of chronic inflammation. The flavonoids were assayed against sheep red blood cell-induced mouse paw oedema as a model of delayed-type hypersensitivity reaction. The most active compound, both in vitro and in vivo, was Tiliroside. It significantly inhibited enzymatic and non-enzymatic lipid peroxidation (IC(50)=12.6 and 28 microM, respectively). It had scavenger properties (IC(50)=21.3 microM) and very potent antioxidant activity in the DPPH test (IC(50)=6 microM). In vivo, Tiliroside significantly inhibited the mouse paw oedema induced by phospholipase A(2)(ED(50)=35.6 mg/kg) and the mouse ear inflammation induced by TPA (ED(50)=357 microg/ear). Pinocembrin was the only flavonoid that exhibited anti-inflammatory activity in the sheep red blood cell-induced delayed-type hypersensitivity reaction. However, only Tiliroside significantly reduced the oedema and leukocyte infiltration induced by TPA.
CONCLUSIONS:
As in the case of other flavonoids, the anti-inflammatory activity of Tiliroside could be based on its antioxidant properties, although other mechanisms are probably involved.

Mol Nutr Food Res. 2012 Mar;56(3):435-45.

Tiliroside, a glycosidic flavonoid, inhibits carbohydrate digestion and glucose absorption in the gastrointestinal tract.[Pubmed: 22173993 ]

Recent studies have reported that Tiliroside, a glycosidic flavonoid, possesses anti-diabetic activities. In the present study, we investigated the effects of Tiliroside on carbohydrate digestion and absorption in the gastrointestinal tract.
METHODS AND RESULTS:
This study showed that Tiliroside inhibits pancreatic α-amylase (IC₅₀ = 0.28 mM) in vitro. Tiliroside was found as a noncompetitive inhibitor of α-amylase with K(i) values of 84.2 μM. In male ICR mice, the increase in postprandial plasma glucose levels was significantly suppressed in the Tiliroside-administered group. Tiliroside treatment also suppressed hyperinsulinemia after starch administration. Tiliroside administration inhibited the increase of plasma glucose levels in an oral glucose tolerance test, but not in an intraperitoneal glucose tolerance test. In human intestinal Caco-2 cells, the addition of Tiliroside caused a significant dose-dependent inhibition of glucose uptake. The inhibitory effects of both sodium-dependent glucose transporter 1 (SGLT1) and glucose transporter 2 (GLUT2) inhibitors (phlorizin and phloretin, respectively) on glucose uptake were significantly inhibited in the presence of Tiliroside, suggesting that Tiliroside inhibited glucose uptake mediated by both SGLT1 and GLUT2.
CONCLUSIONS:
These findings indicate that the anti-diabetic effects of Tiliroside are at least partially mediated through inhibitory effects on carbohydrate digestion and glucose uptake in the gastrointestinal tract.

Bioorg Med Chem. 2002 Mar;10(3):707-12.

Hepatoprotective principles from the flowers of Tilia argentea (linden): structure requirements of tiliroside and mechanisms of action.[Pubmed: 11814859]

The methanolic extract from the flowers of Tilia argentea (linden) was found to show a hepatoprotective effect against D-galactosamine (D-GalN)/lipopolysaccharide (LPS)-induced liver injury in mice.
METHODS AND RESULTS:
By bioassay-guided separation using in vitro D-GalN-induced damage to hepatocytes, five flavonol glycosides were isolated as the hepatoprotective constituents of the methanolic extract. Tiliroside, the principal flavonol glycoside, strongly inhibited serum GPT and GOT elevations at doses of 25-100 mg/kg (p.o.) in D-GalN/LPS-treated mice. By comparing the inhibitory effects of Tiliroside with those of its components alone, the kaempferol 3-O-beta-D-glucopyranoside moiety was found to be essential for the activity, and its effect was suggested to depend on the inhibition of tumor necrosis factor-alpha (TNF-alpha) production, decreased sensitivity of hepatocytes to TNF-alpha, and on the protection of hepatocytes against D-GalN.

Biochim Biophys Acta. 2014 Dec;1840(12):3311-9.

Tiliroside, a dietary glycosidic flavonoid, inhibits TRAF-6/NF-κB/p38-mediated neuroinflammation in activated BV2 microglia.[Pubmed: 25152356]

Tiliroside is a dietary glycosidic flavonoid which has shown in vivo anti-inflammatory activity. This study is aimed at evaluating the effect of Tiliroside on neuroinflammation in BV2 microglia, and to identify its molecular targets of anti-neuroinflammatory action.
METHODS AND RESULTS:
BV2 cells were stimulated with LPS+IFNγ in the presence or absence of Tiliroside. TNFα, IL-6, nitrite and PGE2 production was determined with ELISA, Griess assay and enzyme immunoassay, respectively. iNOS, COX-2, phospho-p65, phospho-IκBα, phospho-IKKα, phospho-p38, phospho-MK2, phosopho-MKK3/6 and TRAF-6 were determined by western blot analysis. NF-κB activity was also investigated using a reporter gene assay in HEK293 cells. LPS-induced microglia ROS production was tested using the DCFDA method, while HO-1 and Nrf2 activation was determined with western blot. RESULTS: Tiliroside significantly suppressed TNFα, IL-6, nitrite and PGE2 production, as well as iNOS and COX-2 protein expression from LPS+IFNγ-activated BV2 microglia. Further mechanistic studies showed that Tiliroside inhibited neuroinflammation by targeting important steps in the NF-κB and p38 signalling in LPS+IFNγ-activated BV2 cells. This compound also inhibited LPS-induced TRAF-6 protein expression in BV2 cells. Antioxidant activity of Tiliroside in BV2 cells was demonstrated through attenuation of LPS+IFNγ-induced ROS production and activation of HO-1/Nrf2 antioxidant system.
CONCLUSIONS:
Tiliroside inhibits neuroinflammation in BV2 microglia through a mechanism involving TRAF-6-mediated activation of NF-κB and p38 MAPK signalling pathways. These activities are possibly due, in part, to the antioxidant property of this compound. Tiliroside is a potential novel natural compound for inhibiting neuroinflammation in neurodegenerative disorders.

Biol Pharm Bull. 1998 Oct;21(10):1077-8.

Anti-complement activity of tiliroside from the flower buds of Magnolia fargesii.[Pubmed: 9821813]

As part of the search for anticomplementary active components from natural products, the anticomplementary properties of methanolic extracts from the flower buds of Magnoliafargesii have been investigated.
METHODS AND RESULTS:
Bioassay-guided chromatographic separation of the active constituents led to the isolation of compound 1, whose structure was identified by spectroscopic methods to be kaempferol 3-O-beta-D-(6"-O-coumaroyl)glucopyranoside (Tiliroside). Tiliroside showed very potent anti-complement activity (IC50=5.4 x 10(-5) M) on the classical pathway of the complement system, even higher than rosmarinic acid, which is a well-known inhibitor against the complement system. On the other hand, the hydrolysates of Tiliroside, kaempferol, astragalin and p-coumaric acid showed very weak activity on this system.

J Nutr Biochem. 2012 Jul;23(7):768-76.

Tiliroside, a glycosidic flavonoid, ameliorates obesity-induced metabolic disorders via activation of adiponectin signaling followed by enhancement of fatty acid oxidation in liver and skeletal muscle in obese-diabetic mice.[Pubmed: 21889885]

Tiliroside contained in several dietary plants, such as rose hips, strawberry and raspberry, is a glycosidic flavonoid and possesses anti-inflammatory, antioxidant, anticarcinogenic and hepatoprotective activities. Recently, it has been reported that the administration of Tiliroside significantly inhibited body weight gain and visceral fat accumulation in normal mice.
METHODS AND RESULTS:
In this study, we evaluated the effects of Tiliroside on obesity-induced metabolic disorders in obese-diabetic KK-A(y) mice. In KK-A(y) mice, the administration of Tiliroside (100 mg/kg body weight/day) for 21 days failed to suppress body weight gain and visceral fat accumulation. Although Tiliroside did not affect oxygen consumption, respiratory exchange ratio was significantly decreased in mice treated with Tiliroside. In the analysis of metabolic characteristics, it was shown that plasma insulin, free fatty acid and triglyceride levels were decreased, and plasma adiponectin levels were increased in mice administered Tiliroside. The messenger RNA expression levels of hepatic adiponectin receptor (AdipoR)-1 and AdipoR2 and skeletal muscular AdipoR1 were up-regulated by Tiliroside treatment. Furthermore, it was indicated that Tiliroside treatment activated AMP-activated protein kinase in both the liver and skeletal muscle and peroxisome proliferator-activated receptor α in the liver. Finally, Tiliroside inhibited obesity-induced hepatic and muscular triglyceride accumulation.
CONCLUSIONS:
These findings suggest that Tiliroside enhances fatty acid oxidation via the enhancement adiponectin signaling associated with the activation of both AMP-activated protein kinase and peroxisome proliferator-activated receptor α and ameliorates obesity-induced metabolic disorders, such as hyperinsulinemia and hyperlipidemia, although it does not suppress body weight gain and visceral fat accumulation in obese-diabetic model mice.