Impact of ethanol and heat stress-dependent effect of ultra-diluted Arnica montana 6 cH on in vitro embryo production in cattle.

This study evaluated the effect of adding ultra-diluted and dynamized Arnica montana 6 cH, and its vehicle (0.3% ethanol) to the in vitro maturation (IVM) medium, in the absence (experiment 1) or presence (experiment 2) of heat stress (HS), on bovine oocyte maturation and in vitro embryo production (IVEP). In experiment 1 (n = 902 cumulus oocyte complexes, COCs), the treatments were 1) IVM medium (Control treatment), 2) IVM medium + 0.3% ethanol, and 3) IVM medium + Arnica montana 6 cH. In experiment 2 (n = 1064 COCs), the treatments were 1) IVM medium without HS, 2) IVM medium under HS, 3) IVM medium + ethanol under HS, and 4) IVM medium + Arnica montana under HS. In the absence of HS (experiment 1), the addition of Arnica montana to the IVM medium had a deleterious effect on the IVEP (cleavage and blastocyst rates) and the total cell number/blastocysts. On the other hand, ethanol (0.3%) increased IVEP in relation to the Control and Arnica montana treatments. However, in the presence of HS during IVM (experiment 2), the addition of ethanol or Arnica montana increased IVEP when compared to the HS treatment alone, and the Arnica montana treatment resulted in greater total cell number/blastocysts compared to the other treatments. In conclusion, this study showed for the first time that the negative or positive effect of Arnica montana 6 cH on IVEP depends on the culture condition (i.e., absence or presence of HS during IVM). On the other hand, ethanol showed beneficial and consistent results on IVEP regardless of exposure to HS.

Smooth muscle relaxant effect of kaurenoic acid, a diterpene from Copaifera langsdorffii on rat uterus in vitro.

The effect of kaurenoic acid, a diterpene isolated from the oleo-resin of the popular medicinal plant Copaifera langsdorffii (Leguminaceae), was analysed on rat uterine muscle responsiveness to various drugs in vitro. Cumulative concentration-response curves to acetylcholine and oxytocin were obtained before and after incubation of uterine segments with up to 160 microm of kaurenoic acid. The maximal contractile response (E(max)) evoked by these agonists was inhibited by kaurenoic acid in a concentration-related manner; at 160 microm, kaurenoic acid depressed the E(max) of oxytocin and acetylcholine by 83% and 91%, respectively. The relaxation caused by kaurenoic acid on oxytocin-induced contraction was unaffected in the presence of tetraethyl ammonium, a compound that blocks the calcium activated potassium channels. It was partially reversed by glibenclamide (10(-5) m), an ATP-sensitive potassium channel blocker. Also, kaurenoic acid at 160 microm concentration was found to inhibit significantly the CaCl(2)-evoked contractile responses in a medium of high potassium and zero calcium. Furthermore, kaurenoic acid was found to relax the sustained tonic contraction induced by acetylcholine, oxytocin, BaCl(2) and KCl in a concentration-dependent way. However, KCl-induced tonic contraction was only weakly inhibited by kaurenoic acid. These data indicate that the diterpene, kaurenoic acid, exerts a uterine relaxant effect acting principally through calcium blockade and in part, by the opening of ATP-sensitive potassium channels.

Investigation on the wound healing activity of oleo-resin from Copaifera langsdorffi in rats.

The wound healing activity of oleo-resin from Copaifera langsdorffii Desf. (Leguminaceae) bark was evaluated in rats on experimental wounds. The oleo-resin was tested by monitoring wound contraction in excised wounds and by measuring tensile strength in healing incision wounds. The topical application of oleo-resin at a concentration of 4% accelerated wound contraction in open wounds. The mean values of wound contraction in oleo-resin treated rats on day 9 was 84.05% +/- 2.37% as against 51.29% +/- 9.54% seen in controls and the difference was statistically significant (p < 0.05). No significant differences in the rates of wound contraction were observed on days 12, 15, 18 and 21. Also, the tensile strength in healing incised wounds was found to be significantly higher in the group of animals treated with 4% oleo-resin on day 5 but not on days 7 and 12 (controls: 35.95 +/- 7.44 g/cm; oleo-resin: 71.48 +/- 5.77 g/cm; p < 0.05). These results indicate the beneficial effect of C. langsdorffii oleo-resin on wound healing and justify its traditional use for the treatment of wounds.

The cytotoxic and embryotoxic effects of kaurenoic acid, a diterpene isolated from Copaifera langsdorffii oleo-resin.

In this work, we studied the effects of kaurenoic acid, a diterpene isolated from the oleo-resin of Copaifera langsdorffii in developing sea urchin (Lytechinus variegatus) embryos, on tumor cell growth in microculture tetrazolium (MTT) test and on mouse and human erythrocytes in hemolysis assay. Continuous exposure of embryos to kaurenoic acid starting immediately after fertilization inhibited the first cleavage (IC(50): 84.2 microM) and progressively induced embryo destruction (IC(50): 44.7 microM and < 10 microM for blastulae and larvae stages, respectively). In MTT assay, kaurenoic acid at a concentration of 78 microM produced growth inhibition of CEM leukemic cells by 95%, MCF-7 breast and HCT-8 colon cancer cells by 45% each. Further, kaurenoic acid induced a dose-dependent hemolysis of mouse and human erythrocytes with an EC(50) of 74.0 and 56.4 microM, respectively. The destruction of sea urchin embryos, the inhibition of tumor cell growth and the hemolysis of mouse and human erythrocytes indicate the potential cytotoxicity of kaurenoic acid.

Anti-inflammatory effect of kaurenoic acid, a diterpene from Copaifera langsdorffi on acetic acid-induced colitis in rats.

Kaurenoic acid, a diterpene from Copaifera langsdorffii (Leguminaceae), was evaluated on rat colitis induced by acetic acid. Rats were pretreated orally (15 and 2 h before) or rectally 2 h before induction of colitis with kaurenoic acid (50 and 100 mg/kg) or vehicle (1 ml, 3% DMSO). Colitis was induced by intracolonic instillation of a 2 ml of 4% (v/v) acetic acid solution and, 24 h later, the colonic mucosal damage was analysed macroscopically for the severity of mucosal damage, the myeloperoxidase (MPO) activity and the malondialdehyde (MDA) levels in the colon segments. A marked reduction in gross damage score (52% and 42%) and wet weight of damaged colon tissue (39% and 32%) were observed in rats that received 100 mg/kg kaurenoic acid, respectively, by rectal and oral routes. This effect was confirmed biochemically by a two- to three-fold reduction of colitis associated increase in MPO activity, the marker of neutrophilic infiltration and by a marked decrease in MDA level, an indicator of lipoperoxidation in colon tissue. Furthermore, light microscopy revealed the marked diminution of inflammatory cell infiltration and submucosal edema formation in the colon segments of rats treated with the test compound. These findings indicate the anti-inflammatory potential of kaurenoic acid in acetic acid-induced colitis.

Gastroprotective effect of Copaifera langsdorffii oleo-resin on experimental gastric ulcer models in rats.

The effects of oleo-resin obtained from the stem bark of Copaifera langsdorffii on ethanol, indomethacin and hypothermic restraint-stress induced gastric lesions were studied in rats. Oral administration of oleo-resin at doses of 200 and 400 mg/kg provided dose-dependent significant protection against gastric damage caused by ethanol and restraint stress, and at a dose of 400 mg/kg it also prevented the gastric ulceration induced by indomethacin. Further, in the 4 h pylorus ligated rats, the accumulation of gastric juice volume and the mucus secretion was significantly enhanced by oleo-resin whereas the total acidity was inhibited. These results highlight the gastroprotective potential of C. langsdorffii oleo-resin and the need for a systematic study on this traditional remedy.