Triterpenes from the stem bark of Protorhus longifolia exhibit anti-platelet aggregation activity

Abstract

Two triterpenes were isolated from the chloroform extract of Protorhus longifolia. Their structures were established through spectral analysis (nuclear magnetic resonance (NMR), infrared (IR), liquid chromatography mass spectrometry (LC-MS)) as 3-oxo-5α-lanosta-8,24-dien-21-oic acid (1) and 3βhydroxylanosta-9,24-dien-24-oic acid (2). The two triterpenes were screened for their antioxidant, cytotoxicity, anti-platelet aggregation and anti-inflammatory activity. The antioxidant activity of the compounds was measured using 1,1′-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3ethylbenzthiazoline-6-sulphonic acid) (ABTS) free radicals scavenging and reduction potential assays. The cytotoxic effects of the compounds was determined against human embryonic kidney (HEK293) and human hepatocellular carcinoma (HepG2) cell lines, while the acute anti-inflammatory activity was determined using the carrageenan-induced rat paw edema model. The anti-platelet aggregation activity of the compounds was separately investigated on thrombin, adenosine diphosphate (ADP), epinephrine and arachidonic acid induced rat platelet aggregation. Although, both compounds exhibited poor antioxidant activities, they showed good concentration dependent anti-platelet aggregation activity. The highest activity by compound 1 (IC 50 of 0.99 mg/ml) was observed on the thrombin-induced platelet aggregation. Compound 2 (3 mg/ml) exhibited anticoagulant activity on whole blood and significantly (P < 0.05) inhibited the acute inflammation of rat paw. The compound also weakly inhibited the growth of HEK293 and HepG2 cells. The triterpenes could be potential pharmacologically active anti-platelet aggregation agents.

Triterpenoids from Protorhus longifolia Exhibit Hypocholesterolemic Potential via Regulation of Cholesterol Biosynthesis and Stimulation of Low-Density Lipoprotein Uptake in HepG2 Cells

“…3β-Hydroxylanosta-9,24-dien-21-oic acid (RA-5) has previously been isolated and characterized from P. longifolia stem bark. 15 The newly identified compound (3α,26-dihydroxytirucalla-7,24-dien-21-oic acid, ARM-2) ( Figure 1 ) was isolated as a white amorphous solid. Its molecular formula was determined to be C 30 H 48 O 4 based on its HRESIMS data, which showed a deprotonated molecular ion peak at m/z 471.3480 [M-H] − (calculated for C 30 H 47 O 4 , 471.3474).…”

“…3β-Hydroxylanosta-9,24-dien-21-oic acid (RA-5) has previously been isolated and characterized from P. longifolia stem bark . The newly identified compound (3α,26-dihydroxytirucalla-7,24-dien-21-oic acid, ARM-2) (Figure ) was isolated as a white amorphous solid.…”

“…The chemical structures of RA-5 and ARM-2 were obtained based on spectral data analysis and by comparing the data with literature values. 14,15 The NMR spectra were recorded at ambient temperature on a Bruker Avance III 400 spectrometer equipped with a BBI probe and an Avance III HD 500 spectrometer with a Prodigy probe. 1 H and 13 C NMR chemical shifts were referenced to residual and solvent peaks at δ H 7.26, δ C 77.0 for CDCl 3 and δ H 2.50, δ C 39.52 for (CD 3 ) 2 SO.…”

“…The collected fractions with similar profile were combined to give Fractions A to T. Fractions H and Q were concentrated and recrystallized in hexane and ethyl acetate, respectively, to yield RA-5 (0.86 g) and ARM-2 (1.38 g). The chemical structures of RA-5 and ARM-2 were obtained based on spectral data analysis and by comparing the data with literature values. , The NMR spectra were recorded at ambient temperature on a Bruker Avance III 400 spectrometer equipped with a BBI probe and an Avance III HD 500 spectrometer with a Prodigy probe. 1 H and 13 C NMR chemical shifts were referenced to residual and solvent peaks at δ H 7.26, δ C 77.0 for CDCl 3 and δ H 2.50, δ C 39.52 for (CD 3 ) 2 SO.…”

The Antibacterial Activities of Some Plant Derived Triterpenes

“…It is also an opportunistic pathogen in immunocompromised patients causing severe endophthalmitis, bacteremia, septicemia, endocarditis, pneumonia, meningitis, gastritis, and cutaneous infections (Senesi and Ghelardi, 2010); Vibrio bacteria is incriminated in mostly gastrointestinal and extra-intestinal diseases in man (Health protection agency, 2007); Enterococcus bacteria are common causes of nosocomial infections (Arias et al, 2010), such as catheter-associated urinary tract infections, endocarditis as well as surgical and burn wound infections (Abranches et al, 2013) ; E. coli bacteria, mostly the shiga toxin producing serotypes cause mild to bloody diarrhoea, haemorrhagic colitis, and hemolytic-uremic syndrome (HUS) (Brooks et al, 2005). Treatment of these various bacterial infections is, however, being hindered by the prevalence of antibiotic resistant strains (Furtula et al, 2013;Banerjee et al, 2013;Ghaima et al, 2013;Costa et al, 2014), and this therefore necessitates the need for newer and effective antimicrobials of which the before mentioned plant triterpenes offer a viable alternative considering their vast beneficial therapeutic potentials (Mosa et al, 2011;Machaba et al, 2014;Penduka et al, 2014).…”