Preclinical safety assessment of the crude extract from Sida rhombifolia L. aerial parts in experimental models of acute and repeated-dose 28 days toxicity in rats.

Sida rhombifolia (Malvaceae) is popularly used as a treatment for several pathological conditions; however, there is a lack of studies that identify its compounds and that evaluate comprehensively the safety of its consumption. Therefore, the aim of this study was to determinate the phytochemical constitution of the crude extract of Sida rhombifolia (CESR), and its safety in models of acute and repeated doses (28 days) toxicity. The tested dose for the model of acute toxicity was 2000 mg/kg doses for the repeated dose model were 150, 300 e 600 mg/kg. Hematological, biochemical, histopathological and oxidative markers were investigated. HPLC-DAD-MS analysis evidenced the presence of caffeic acid, coumarin, and rutin. In the acute toxicity model the only altered parameters were tissue ROS, and AST and BUN in serum. As for the repeated dose experiment both hematological and biochemical markers remained within the values of reference for the species. Obtained results demonstrate that the CESR did not present significant toxic effects when administrated orally to male and female rats in acute and repeated doses.

Inhibition of desmoglein-1 by aspirin leads to synthetic lethality of keratinocytes in Shuanghuanglian-induced cutaneous eruption response.

Cutaneous eruptions caused by the combination of Chinese and Western medicine have attracted widespread attention; however, the underlying mechanism remains unclear. This study aimed to evaluate the potential mechanism of cutaneous eruptions in vivo and in vitro using the combination of Shuanghuanglian injection powder (SHL) and aspirin (ASA) as an example. ASA and SHL co-administration induced inflammatory responses in HaCat cells, as evidenced by marked increases in the expression of IL-4 and TNF-α, and the level of apoptosis. Additionally, histopathological investigation of mice skin tissues showed local inflammatory cell infiltration. Western boltting was used to detect the effects of ASA on desmoglein-1 (DSG1) expression; we found that DSG1 expression was down-regulated in vivo and in vitro. Finally, the key components of SHL were administered to HaCat cells with down-regulated DSG1; it was seen that neochlorogenic acid and rutin have a significant effect on HaCat cell apoptosis. These results demonstrate that DSG1 deficiency is a potential cause of cutaneous eruptions caused by the combination of SHL and ASA, and neochlorogenic acid and rutin are the main allergenic components. This study provides a new research strategy for the safety evaluation of integrated traditional Chinese and Western medicine.

The mutagenic potency of onion juice vs. its contents of quercetin and rutin.

In spite of its considerable value as a predictor of in vivo genotoxicity and even for carcinogenicity, false positive cases were reported for the Ames test, e.g., with a number of natural food constituents. Here we analyzed the effects of juice of Allium cepa, the common onion, a staple food and traditional remedy used in many civilizations, in the Ames fluctuation assay. We could find mild mutagenicity with an onion juice extract in Salmonella typhimurium strains TA98 and TA100, the latter being less sensitive towards the extract. Mutagenicity was not influenced markedly by the presence of rat liver S9 mix. Onion juice also exerted some toxicity to the bacteria in the same concentration range. Comparative studies with quercetin and rutin, major flavonoid glycosides in onions, revealed a mutagenic potency of quercetin with an EC50-value of 4 µM in TA98. The contents of quercetin and rutin in onion juice were determined as 0.71 ± 0.20, and 0.71 ± 0.21 mg/kg. Calculations of quercetin and rutin concentrations in mutagenic dilutions revealed that both compounds are highly unlikely to cause the mutagenic effects of onion juice and that other yet undefined constituents must be responsible for these effects.

Assessment of allelopathic, cytotoxic, genotoxic and antigenotoxic potential of Smilax brasiliensis Sprengel leaves.

Smilax brasiliensis (Smilacaceae) is a native Brazilian plant found in the Cerrado biome and commonly used in folk medicine. The aim of this study was to evaluate the allelopathic, cytotoxic, genotoxic, and antigenotoxic potential of extract and fractions of Smilax brasiliensis leaves. Quercetin and rutin isomers were observed in the subfractions. The dichloromethane fraction (1000 µg/mL) decreased lettuce (Lactuca sativa) seed vigor, while and ethyl acetate and hydromethanol fractions (1000 µg/mL) affected the germination, and quercetin and rutin affected the vigor and germination of onion seeds. The extract, fractions, quercetin, and rutin inhibited or promoted lettuce hypocotyl and radicle growth. The extract and fractions inhibited onion hypocotyl growth at all concentrations. With regards to radicle growth, the results were diversified: growth was either inhibited or promoted. Rutin and quercetin inhibited onion hypocotyl and radicle growth at all concentrations. The extract and fractions of Smilax brasiliensis, rutin, and quercetin did not cause cytotoxic effect evaluated by mitotic index. The extract and fractions showed genotoxic effects. Quercetin and rutin did not cause genotoxic effects. On the other hand, the extract and fractions showed antigenotoxic effects at all tested concentrations, where they were able to revert chromosomal abnormalities caused by glyphosate. However, additional studies are required to evaluate the possible use of the S. brasiliensis leaf methanol extract and fractions as natural sources of bioherbicides.

In Vivo Hypoglycemic Studies of Polyherbal Phytoceuticals, Their Pharmacokinetic Studies and Dose Extrapolation by Allometric Scaling.

BACKGROUND: This work reports the safety profiling, in vivo hypoglycemic and pharmacokinetic studies of three phytoceuticals viz. conventional and sustained release tablets and microspheres each containing a polyherbal product phytocomposite (PHC) as the active ingredient. PHC is prepared from the leaf extracts of Ficus benghalensis: Syzigium cumini: Ocimum sanctum mixed in the weight ratio of 1:1:2. Further no observed adverse effect level (NOAEL), maximum recommended starting dose (MRSD) in human and prediction of human pharmacokinetic parameters have been accomplished by allometric equations. METHODS: Acute and sub chronic studies of the phytoceuticals were done as per OECD and in vivo hypoglycemic studies in STZ induced diabetic rats. Plasma concentrations of the active constituent rutin (pharmacologically active compound of PHC) were determined by HPLC and other pharmacokinetic parameters using PK Solver. Repeated dose toxicity was carried out to determine the NOAEL value, MRSD estimated using allometric formulas of body surface area and clearance (CL) and volume of distribution (Vd) predicted by allometric equations of single species scaling. RESULTS: Phytoceuticals showed a wide range of safety profile with a significant lowering of blood gluco-lipid level. The values of the pharmacokinetic parameters for different doses of phytoceuticals showed that the active concentration was maintained in plasma level and each formulation complied with their relevant quality criteria. NOAEL value was 5000 mg/kg/body weight and MRSD was 4864.86 mg. CONCLUSION: Phytoceuticals prepared are safe and effectively controlled blood gluco lipid level. Animal to human dose extrapolation and prediction of human pharmacokinetic parameters by allometry was convenient.

Evaluation of antigenotoxic effects of plant flavonoids quercetin and rutin on HepG2 cells.

The flavonoid quercetin and its derivative rutin were investigated for genotoxicity/antigenotoxicity activity in human hepatoma HepG2 cells using the comet assay. The extract cytotoxicity was evaluated using the trypan blue exclusion dye method with quercetin and rutin concentrations ranging from 0.1 to 200.0 µg/mL of culture medium. Three minor non-cytotoxic concentrations were chosen to evaluate the genotoxicity and antigenotoxicity of the flavonoids (0.1, 1.0 and 5.0 µg/mL) through comet assay. The cultures were treated with three different concentrations of rutin or quercetin (genotoxicity) or their association with Aflatoxin B1 (AFB1), methyl methanesulfonate (MMS) or doxorubicin (DXR) (antigenotoxicity test) in three protocols: pre-treatment, simultaneous treatment and post-treatment. The cell cultures were also treated with 1% DMSO (control group), AFB1, MMS and DXR (positive-control). Statistical analyses were performed using ANOVA and Dunnett's test (p ≤ 0.05). Quercetin at concentrations higher than 10.0 µg/mL or rutin higher than 50.0 µg/mL exhibited a cytotoxic effect on the cells, showing that quercetin is more cytotoxic than rutin. Furthermore, neither compound was able to induce genotoxicity in the concentrations evaluated. On the other hand, both flavonoids reduced DNA damage induced by AFB1, MMS and DXR in all treatment protocols.

In vitro pollen tube growth reveals the cytotoxic potential of the flavonols, quercetin and rutin.

Flavonols are phytochemicals widely found in commonly consumed foods. In spite of their beneficial effects on human health, however, cytotoxicity and even suspected genotoxicity have also been reported for the flavonol, quercetin. This points to the need for preventive studies to identify any cytotoxic effects associated with pure flavonol intake. This work was performed with the aim of verifying whether a plant-based in vitro system, the pollen tube, could be used to evaluate the cytotoxic potential of exogenous flavonols. Increasing concentrations of the aglycone, quercetin, and its glycoside, rutin, were assayed with regard to tube growth of kiwifruit pollen, determined by applying the pollen tube growth test protocol. This test, based on the photometric quantification of pollen tube mass production in suspension cultures, has already been applied in the sensitive and reliable toxicological evaluation of a wide range of chemicals. Whereas 60-800 microM rutin promoted kiwifruit pollen tube elongation, 10-50 microM quercetin strongly inhibited growth, and also produced irreversible malformations, such as screw-like tube growth, abnormal vacuolation, alteration of organelle streaming, and nuclear positioning. Thus, the cytotoxic potentials of the two flavonols have been confirmed to differ. Pollen tubes seem to afford a promising test system for a preventive, rapid in vitro biosafety assessment of antioxidant nutritional supplements, without using laboratory animals.

Efeito de rutina sobre os níveis de cloreto, cálcio e fósforo em soro de coelhos / Effects of differents rutin dosages on chloride, calcium and phosphorum levels in serum of rabbits

The objective of this research was to evaluate in rabbits the effect of different dosages rutin in seric levels of chloride, calcium and phosphoro. Rabbits of New Zealand strain aged 55 days of age were used. The animals were divides in males and females, being constituted 4 groups by sex, containing each one 5 animals, that received rutin in the dosages of 20, 40 and 60 mg. The controls groups received only the ration. Samples of blood were collected by retro-orbital vein plexo puncture being then centrifuged at 3500 x g for 15 minutes and serum measurement determined in a multiparametric doage of biochemistry (Alizé). For chloride results it was observed that rutin in the tested doses were significant for males although the variations were not considered toxic. It was also observed that the males presented significant values in dosis of 20 mg of rutin when compared with the females. Being analyzed the medium sanguine values of match and being compared males and female, significant differences were verified with the group that received 20 mg of rutin. Whith relatonship at the levels of calcium, this didn´t present significant alterations when we compared male and females. The females submitted to 20 mg rutin presented altered calcium levels, however those alterations did not present omportant physiologic significance once the other doses didn´t act in significant variations in the levels of calcium. It is concluded that the presented variations were not considered toxic for the parameters chloride, calcium and match in the blood of rabbits.

Effect of chronic therapy with proteolytic enzymes on hypertension-induced renal injury in the rat model of Goldblatt hypertension.

This study investigated the possible beneficial effect of intraperitoneal proteolytic enzyme administration on the development of hypertension-induced renal injury in the rat model of 2-kidney 1-clip (2K1C) Goldblatt hypertension. Male Wistar rats (120-150 g) underwent either sham surgery (control, n = 5) or clipping of the left renal artery. From day one 2K1C rats were randomized into 2 groups, placebo treatment (n = 7), and proteolytic enzyme treatment (n = 9). To the verum group a fixed mixture of trypsin (2.42 mg), bromelain (4.54 mg), and rutin (5.04 mg) dissolved in 2 ml of sterile 0.9% NaCl was administered intraperitoneally daily, while the placebo group received only vehicle. Rats were pair-fed. The duration of the study was 7 weeks. All 2K1C rats developed hypertension and the mean values of systolic blood pressure (SBP) did not differ significantly between the groups at any time recorded (SBP at sacrifice: controls 122.0 +/- 8.5 mm Hg; placebo 191.4 +/- 7. 6 mm Hg; enzyme 180.5 +/- 6.5 mm Hg). Enzyme treatment prevented the rise in proteinuria (controls 12.4 +/- 2.6 mg/24 h; placebo 19.7 +/- 3.9 mg/24 h; enzyme 12.2 +/- 1.3 mg/24 h; p < 0.05) and ameliorated the increase in serum urea concentrations. Histomorphologically, signs of malignant nephrosclerosis were not found in control rats, while they were present in 4/7 (57%) of placebo-treated rats, but only in 1/9 (11%) of the enzyme-treated group. The volume fraction of renocortical interstitium was increased in both 2K1C groups in comparison with controls; however, enzyme treatment decreased the accumulation of interstitial tissue significantly (-22%) compared to placebo treatment. Cellular infiltration with mononuclear cells was also lower in the protease-treated group. To summarize, in the rat model of 2K1C hypertension, systemic treatment with proteases ameliorates the severity of nephrosclerosis and tubulointerstitial fibrosis in the non-clipped kidney, as well as proteinuria, without affecting high blood pressure.

Effects of protease therapy in the remnant kidney model of progressive renal failure.

This study investigated whether protease treatment ameliorates the progressive course of chronic failure in the rat model of subtotal nephrectomy. Fourteen male Wistar rats underwent 5/6 nephrectomy, and were randomized into a control group (C, n = 7) given 2 ml of 0.9% NaCl intraperitoneally (i.p.) daily, and a study group (P, n = 7) treated with 12 mg Phlogenzym (combination of trypsin, bromelain, and rutosid) in 2 ml saline i.p. daily. After 6 weeks treatment, the Phlogenzym group showed lower proteinuria (C: 19.6 +/- 9.1 vs. 10.2 +/- 6.2 mg/24 h, p < 0.05). Endogenous creatinine clearance was higher (C: 192.3 +/- 99.4, P: 300.5 +/- 47.9 microliters/min per 100 g, p < 0.05), while plasma creatinine was decreased (C: 106.7 +/- 33.9, P: 76.0 +/- 6.3 mumol/l, p < 0.01). Blood urea nitrogen levels did not change, although urea clearance tended to a higher level in the protease-treated rats. Decreased renal formation of cytokines was reflected by a lower urinary excretion ratio of transforming growth factor (TGF)-beta/ creatinine (C: 0.363 +/- 0.183, P: 0.232 +/- 0.085 ng TGF-beta/mg creatinine, p < 0.05). Renal morphology revealed less infiltration of mononuclear cells and an amelioration of interstitial fibrosis as expressed by the volume index of the cortical region (C: 17.17 +/- 1.43; P: 12.3 +/- 0.5%, p < 0.001). In addition, the activities of lysosomal proteinases (cathepsin B, L + B, and H), which are decreased in the remnant kidney model of chronic renal failure, were significantly higher in the enzyme-treated group both in isolated glomeruli and proximal tubules. The body and kidney weight tended to be lower, probably due to a catabolic action of the enzymes. In summary, we provide evidence that protease treatment may be beneficial in a nonimmune mediated renal disease. Phlogenzym ameliorated the course of chronic renal failure in the rat model of subtotal nephrectomy and retarded the development of tubulointerstitial fibrosis. Decreased cytokine formation in the remnant kidney is supposed to play a key role.

Monohydroxyethylrutoside, a dose-dependent cardioprotective agent, does not affect the antitumor activity of doxorubicin.

The cumulative dose-related cardiotoxicity of doxorubicin is believed to be caused by the production of oxygen- free radicals. 7-Monohydroxyethylrutoside (monoHER), a semisynthetic flavonoid and powerful antioxidant, was investigated with respect to the prevention of doxorubicin-induced cardiotoxicity in mice and to its influence on the antitumor activity of doxorubicin in vitro and in vivo. Non-tumor-bearing mice were equipped with a telemeter in the peritoneal cavity. They were given six weekly doses of 4 mg/kg doxorubicin i.v., alone or in combination with either 100 or 250 mg/kg monoHER i.p., 1 h prior to doxorubicin administration and for the following 4 days. Cardiotoxic effects were measured from electrocardiogram changes up to 2 weeks after treatment. Protection against cardiotoxicity was found to be dose dependent, with 53 and 75% protection, respectively, as calculated from the reduction in the increase in the ST interval. MonoHER and several other flavonoids with good antioxidant properties were tested for their antiproliferative effects in the absence or the presence of doxorubicin in A2780 and OVCAR-3 human ovarian cancer cells and MCF-7 human breast cancer cells in vitro. Some flavonoids were directly toxic at 50 and 100 microM, whereas others, including monoHER, did not influence the antiproliferative effects of doxorubicin at these concentrations. The influence of monoHER was further tested on the growth-inhibitory effect of 8 mg/kg doxorubicin i.v., given twice with an interval of 1 week in A2780 and OVCAR-3 cells that were grown as s.c. xenografts in nude mice. MonoHER, administered 1 h before doxorubicin in a dose schedule of 500 mg/kg i.p. 2 or 5 days per week, was not toxic and did not decrease the antitumor activity of doxorubicin. It can be concluded that monoHER showed a dose-dependent protection against chronic cardiotoxicity and did not influence the antitumor activity of doxorubicin in vitro or in vivo.

[The semisynthetic production of pharmacologically active flavone derivatives. I. The pharmaco-toxicological properties of theophylline-rutozide (TR 1722)]. / Cercetari privind obtinerea prin semisinteza a unor derivati flavonici farmacologic activi. I. Unele însusiri farmaco-toxicologice ale teofilin-rutozidului (TR 1722).

The pharmaco-toxicological properties of the compound theophylline-rutozide, termed conventionally TR-1722, are presented. Studied comparatively with aminophylline, it presents important advantages: soluble in water, the aqueous solutions have a pH close to the physiological one and are stable. It induces a weaker excitation on the central nervous system as compared to aminophylline, but its antihistaminic and anti-inflammatory properties are slightly increased. The physicochemical and pharmacological properties of TR 1722 recommend it for the patients with asthma and associated arterial hypertension or obstructive bronchopneumopathy associated with pulmonary hypertension.

Carcinogenicity test of quercetin and rutin in golden hamsters by oral administration.

Quercetin and its glycoside, rutin were tested for carcinogenicity in non-inbred golden hamsters of both sexes. In Experiment I, 10% quercetin, 10% rutin, or control diet was given to animals for 735 days. In this experiment, tumors appeared mainly in the forestomach, but the incidence was not statistically different among the three groups. Quercetin and rutin were not carcinogenic under these conditions. In Experiment II, Group 1 was given 4% quercetin diet for 709 days. Group 2 was given 1% quercetin diet for 351 days and then the basal diet for 350 days. Group 3 was given 1% quercetin diet and then 1% croton oil diet and Group 4 was given the basal diet followed by 1% croton oil diet, for the same periods as Group 2. Group 5 was given the basal diet for 701 days. In Experiment II, papillomas of the forestomach appeared in Groups 1, 2, and 5, and papillomatosis in Group 3 and 4. There were no statistical differences among experimental groups and respective controls. Thus, quercetin was not carcinogenic when given at the concentrations of 4% and 1%; even with the administration of 1% croton oil after 1% quercetin, there was no increase in tumor incidence.