Hepatotoxicity associated with herbal products

Repeated oral dose toxicity and genotoxicity of a standardized Quisqualis indica extract

Quisqualis indica L. of Combretaceae family is a traditional medicine that is widely used for various gastrointestinal discomfort including stomach pain, constipation, and digestive problem. In this study, the potential repeated dose toxicity and genotoxicity of a standardized Quisqualis indica L. extract (HU033) were determined under good laboratory practice conditions. For the repeated dose toxicity test, HU033 was orally administered to Sprague-Dawley (SD) rats at doses of 500, 1000, and 2000 mg/kg/day for 13 consecutive weeks. The genotoxicity of HU033 was determined with a standard battery of genotoxicity test, including an in vitro bacterial reverse mutation test, an in vitro chromosomal aberration test, and an in vivo micronucleus test. After 13 weeks of repeated dose of HU033 by oral administration, there was no treatment related adverse clinical sign including food consumption, organ weights, and histopathological findings or significant decrement in bodyweight. The no-observed-adverse-effect level of HU033 was higher than 2000 mg/kg in both male and female SD rats. No target organs were identified. In addition, no evidence of HU033 genotoxicity was detected based on results from the bacterial reverse mutation test, chromosomal aberration test, and micronucleus test. Based on results of this study, HU033 could be safely used in food and medical products within the tested dose range.

Using herbs medically without knowing their composition: are we playing Russian roulette?

Herbal medicine, a form of complementary and alternative medicine (CAM), is used throughout the world, in both developing and developed countries. The ingredients in herbal medicines are not standardized by any regulatory agency. Variability exists in the ingredients as well as in their concentrations. Plant products may become contaminated with bacteria and fungi during storage. Therefore, harm can occur to the kidney, liver, and blood components after ingestion. We encourage scientific studies to identify the active ingredients in herbs and to standardize their concentrations in all herbal preparations. Rigorous studies need to be performed in order to understand the effect of herbal ingredients on different organ systems as well as these substances' interaction with other medications.

A UHPLC-UV Method Development and Validation for Determining Kavalactones and Flavokavains in Piper methysticum (Kava)

An ultra-high-performance liquid chromatographic (UHPLC) separation was developed for six kava pyrones (methysticin, dihydromethysticin (DHM), kavain, dihydrokavain (DHK), desmethoxyyangonin (DMY), and yangonin), two unidentified components, and three Flavokavains (Flavokavain A, B, and C) in Piper methysticum (kava). The six major kavalactones and three flavokavains are completely separated (Rs > 1.5) within 15 min using a HSS T3 column and a mobile phase at 60 °C. All the peaks in the LC chromatogram of kava extract or standard solutions were structurally confirmed by LC-UV-MS/MS. The degradations of yangonin and flavokavains were observed among the method development. The degradation products were identified as cis-isomerization by MS/MS spectra. The isomerization was prevented or limited by sample preparation in a non-alcoholic solvent or with no water. The method uses the six kava pyrones and three flavokavains as external standards. The quantitative calibration curves are linear, covering a range of 0.5⁻75 μg/mL for the six kava pyrones and 0.05⁻7.5 μg/mL for the three flavokavains. The quantitation limits for methysticin, DHM, kavain, DHK, DMY, and yangonin are approximately 0.454, 0.480, 0.277, 0.686, 0.189, and 0.422 μg/mL. The limit of quantification (LOQs) of the three flavokavains are about 0.270, 0.062, and 0.303 μg/mL for flavokavain C (FKC), flavokavain A (FKA), and flavokavain B (FKB). The average recoveries at three different levels are 99.0⁻102.3% for kavalactones (KLs) and 98.1⁻102.9% for flavokavains (FKs). This study demonstrates that the method of analysis offers convenience and adequate sensitivity for determining methysticin, DHM, kavain, DHK, yangonin, DMY, FKA, FKB, and FKC in kava raw materials (root and CO₂ extract) and finished products (dry-filled capsule and tablet).

Evaluation of acute toxicity, genotoxicity and inhibitory effect on acute inflammation of an ethanol extract of Morus alba L. (Moraceae) in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Morus alba L. (white mulberry) is used in traditional medicine worldwide, including Brazil. The leaves of this plant are used to treat inflammatory disorders. Universal interest in this plant necessitates studies on the toxicological safety and scientific substantiation of the medicinal properties of M. alba. In previous work, we investigated the acute toxicity of orally administered M. alba ethanol extract in mice.

AIM OF THE STUDY

This work was designed to investigate the ethanol extract obtained from M. alba leaves for acute toxicity when intraperitoneally administered, in vivo genotoxicity, and potential to reduce acute inflammation. In order to further investigate the constituents of the extract, we also obtained the high-performance liquid chromatography (HPLC) fingerprint of the extract.

MATERIALS AND METHODS

Phytochemical analysis by thin layer chromatography (TLC) was performed and the results were used to obtain the HPLC fingerprint. Acute toxicity of 300 and 2000mg/kg b.w. i.p. doses administered to mice for 14 days was evaluated. Genotoxicity was evaluated by counting the number of micronucleated polychromatic erythrocytes in the blood of mice that either received or did not receive the extract at 75, 150 and 300mg/kg b.w. per os. The anti-inflammatory effect of the same doses administered per os was investigated using the carrageenan air pouch model.

RESULTS

The TLC analysis of the extract revealed the presence of a remarkable amount of flavonoids and cinnamic acids. The HPLC fingerprint showed the presence of one major peak corresponding to chlorogenic acid and two smaller peaks corresponding to flavonoids. In the toxicity assays, there were no deaths or deviations in behavior of treated mice as compared to the control at any dose. However, biochemical, hematological, and histological analyses showed that intraperitoneal injection caused several forms of damage to the mice, which were not observed in case of oral administration, studied in our previous work. Oral administration of the extract did not result in genotoxicity and considerably reduced (58.6-65.6% inhibition) leukocyte migration in all doses evaluated, in comparison with the negative control.

CONCLUSIONS

The ethanol extract from M. alba leaves administered intraperitoneally possesses a greater degree of toxicity in mice when compared to per os administration. The extract was not genotoxic when ingested by mice and exhibited a highly inhibitory effect against acute inflammation, which is probably linked to the presence of chlorogenic acid and flavonoids in the composition. This work contributes to the determination of safety of the medicinal use of M. alba leaves.

Hepatotoxicity evaluation of aqueous extract from Scutia buxifolia

Nowadays there is an increase in the number of people taking herbals worldwide. Scutia buxifolia is used for the treatment of hypertension, but little is known about its action on liver. Thirty-two Wistar rats were divided into four groups: control and groups treated during 30 days with 100, 200 and 400 mg of lyophilized aqueous extract of S. buxifolia (SBSB)/kg of body weight. This study was planned to explore hepatotoxic effect of SBSB, which was assessed by serum transaminases (ALT and AST). Thiobarbituric acid reactive substances (TBARS) levels were determined in liver, along with thiols content (NPSH), catalase (CAT) activity and, superoxide dismutase (SOD) enzymes. Histopathological studies of liver tissue were performed. Flavonoids and phenolics were quantified in SBSB by high performance liquid chromatography with diode array detection (HPLC/DAD). We did not observe alterations on redox status (TBARS, NPSH, CAT and, SOD) in the control and experimental groups. An increase on AST activity was only observed at 200 mg of SBSB, whereas ALT score was not affected by SBSB. Moreover, no morphological alterations were observed on the hepatocytes, matching the analysed biochemical parameters. This way, we conclude that SBSB was not toxic.

Biological reactive intermediates (BRIs) formed from botanical dietary supplements

The use of botanical dietary supplements is increasingly popular, due to their natural origin and the perceived assumption that they are safer than prescription drugs. While most botanical dietary supplements can be considered safe, a few contain compounds, which can be converted to biological reactive intermediates (BRIs) causing toxicity. For example, sassafras oil contains safrole, which can be converted to a reactive carbocation forming genotoxic DNA adducts. Alternatively, some botanical dietary supplements contain stable BRIs such as simple Michael acceptors that react with chemosensor proteins such as Keap1 resulting in induction of protective detoxification enzymes. Examples include curcumin from turmeric, xanthohumol from hops, and Z-ligustilide from dang gui. Quinones (sassafras, kava, black cohosh), quinone methides (sassafras), and epoxides (pennyroyal oil) represent BRIs of intermediate reactivity, which could generate both genotoxic and/or chemopreventive effects. The biological targets of BRIs formed from botanical dietary supplements and their resulting toxic and/or chemopreventive effects are closely linked to the reactivity of BRIs as well as dose and time of exposure.

Complementary and alternative medicine use in chronic liver disease patients

GOALS

To examine a wide range of sociodemographic and clinical characteristics as potential predictors of complementary and alternative medicine (CAM) use among chronic liver disease (CLD) patients, with a focus on CAM therapies with the greatest potential for hepatotoxicity and interactions with conventional treatments.

BACKGROUND

There is some evidence that patients with CLD commonly use CAM to address general and CLD-specific health concerns.

STUDY

Patients enrolled in a population-based surveillance study of persons newly diagnosed with CLD between 1999 and 2001 were asked about current use of CAM specifically for CLD. Sociodemographic and clinical information was obtained from interviews and medical records. Predictors of CAM use were examined using univariate and multivariate logistic regression analysis.

RESULTS

Of the 1040 participants, 284 (27.3%) reported current use of at least 1 of 3 CAM therapies of interest. Vitamins or other dietary supplements were the most commonly used therapy, reported by 188 (18.1%) patients. This was followed by herbal medicine (175 patients, 16.8%) and homeopathy (16 patients, 1.5%). Several characteristics were found to be independent correlates of CAM use: higher education and family income, certain CLD etiologies (alcohol, hepatitis C, hepatitis C and alcohol, and hepatitis B), and prior hospitalization for CLD.

CONCLUSIONS

Use of CAM therapies that have the potential to interact with conventional treatments for CLD was quite common among this population-based sample of patients with CLD. There is a need for patient and practitioner education and communication regarding CAM use in the context of CLD.

Drug-induced liver injury: Is it somehow foreseeable?

The classic view on the pathogenesis of drug-induced liver injury is that the so-called parent compounds are made hepatotoxic by metabolism (formation of neo-substances that react abnormally), mainly by cytochromes P-450 (CYP), with further pathways, such as mitochondrial dysfunction and apoptosis, also playing a role. Risk factors for drug-induced liver injury include concomitant hepatic diseases, age and genetic polymorphisms of CYP. However, some susceptibility can today be predicted before drug administration, working on the common substrate, by phenotyping and genotyping studies and by taking in consideration patients’ health status. Physicians should always think of this adverse effect in the absence of other clear hepatic disease. Ethical and legal problems towards operators in the health care system are always matters to consider.

Surveillance of suspected adverse reactions to natural health products in Italy

PURPOSE

Natural health products are promoted to the public as equally or more effective and less toxic than conventional drugs. However, some 'natural' medicines, and in particular some herbal medicines, are known to have adverse effects. The Italian Pharmacovigilance System, in charge of the Italian Medicines Agency, collects spontaneous reports only for registered drugs. The awareness of the need of surveillance of the safety of natural health products has stimulated the implementation of a suspected adverse reaction reporting system in Italy. The system has been set up by the Italian National Institute of Health.

METHODS

An ad hoc reporting form can be downloaded from different institutional web sites. Voluntary reports of suspected adverse reactions are sent to the National Institute of Health and are evaluated by a multidisciplinary group of experts.

RESULTS

From April 2002 to March 2007, 233 spontaneous reports of suspected adverse reactions to natural health products were collected. A large proportion of suspected adverse reactions were serious: hospitalization was reported in 35% of forms; 6% reported life threatening clinical events and two fatal events were notified. About 50% of suspected adverse reactions were related to gastrointestinal, skin, psychiatric and nervous system disorders. Mainly herbal products (66%) were involved. Twenty-one cases of hepatitis of various seriousness were reported. Twenty-one reports were associated with 27 homeopathic preparations, mostly preparations containing mixtures of substances. Fourteen reports regarded suspected reactions to products containing propolis.

CONCLUSION

Safety and efficacy of 'natural' medicines have not been thoroughly investigated. It is important to improve communication with the public on safety issues. Encouraging spontaneous reporting can contribute to improve awareness among health personnel and patients about the benefit-harm profile of these remedies.