Liver toxicity mechanisms of herbs commonly used in Latin America.

Mexico owns approximately 4500 medicinal plants species, a great diversity that position it at the second place after China. According to the Mexican health department, 90% of common population consumes them to treat various diseases. Additionally, herbal remedies in Latin America (LA) are considered a common practice, but the frequency of use and the liver damage related to its consumption is still unknown. Despite the high prevalence and indiscriminate herbal consumption, the exact mechanism of hepatotoxicity and adverse effects is not fully clarified and is still questioned. Some herb products associated with herb induced liver injury (HILI) are characterized by presenting a different chemical composition that may vary from batch to batch, also the biological activity of many medicinal plants and other natural products are directly related to their most active component and its concentration. There are two main biological components that are associated with liver damage, alkaloids, and flavonoids, which are frequent constituents of commonly used herbs. The interaction with the different cytochrome P-450 isoforms, inflammatory, and oxidative activities seem to be the main damage pathway involved in the liver. It is important to know the herbal adverse effects and mechanisms involved; therefore, this article is focused on the beneficial and deleterious effects as well as the possible toxicity mechanisms and interactions of the herbs that are frequently used in LA, since the herb-host interaction may not always be the expected or desired depending on the clinical context in which it is administered.

Role of bioactive fatty acids in nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) is characterized by fat deposition in hepatocytes, and a strong association with nutritional factors. Dietary fatty acids are classified according to their biochemical properties, which confer their bioactive roles. Monounsaturated fatty acids have a dual role in various human and murine models. In contrast, polyunsaturated fatty acids exhibit antiobesity, anti steatosic and anti-inflammatory effects. The combination of these forms of fatty acids-according to dietary type, daily intake and the proportion of n-6 to n-3 fats-can compromise hepatic lipid metabolism. A chemosensory rather than a nutritional role makes bioactive fatty acids possible biomarkers for NAFLD. Bioactive fatty acids provide health benefits through modification of fatty acid composition and modulating the activity of liver cells during liver fibrosis. More and better evidence is necessary to elucidate the role of bioactive fatty acids in nutritional and clinical treatment strategies for patients with NAFLD.

Herbal Medicine in Mexico: A Cause of Hepatotoxicity. A Critical Review.

In Mexico, herbal products are commonly used as therapeutic tools. The analysis of several publications reveals that there are dozens of different herbs and herbal products used for different reasons, some of which have been implicated in causing toxic liver disease. However, methodological aspects limit the attribution of causality, and the precise incidence and clinical manifestations of herb-induced liver injury have not been well characterized. This review outlines the history of traditional herbal medicine in Mexico, critically summarizes the mechanisms and adverse effects of commonly used herbal plants, and examines the regulatory issues regarding the legal use of these products.

A systematic review and meta-analysis of the use of oral zinc in the treatment of hepatic encephalopathy.

BACKGROUND AND AIM: Because low serum zinc levels precipitate hepatic encephalopathy, zinc supplementation is considered a potential therapeutic option. The aim of this study was to assess the effects of oral zinc supplementation in the treatment of hepatic encephalopathy. METHODS: For this systematic review and meta-analysis, data sources included electronic databases (CENTRAL, MEDLINE, EMBASE) and manual searching. Randomized clinical trials of adult patients diagnosed with liver cirrhosis and hepatic encephalopathy were included. The types of interventions considered were any oral zinc supplementation versus no intervention, placebo, or other interventions for the management of hepatic encephalopathy. The data were analyzed by calculating the RR for each trial and expressing the uncertainty as 95% CI. Continuous data were analyzed by calculating the standard mean differences (SMD) between groups within each trial and their 95% CI. Statistical heterogeneity was defined as a P-value > 0.10 (χ2) or I2 > 25%. RESULTS: Four trials with a total of 233 patients were included. Oral zinc supplementation was associated with a significant improvement in performance on the number connection test (SMD -0.62; 95% CI -1.12 to -0.11) reported in three trials (n = 189), but not with encephalopathy recurrence reduction (RR 0.64; 95% CI 0.26 to 1.59) reported in two trials (n = 169). Other clinically significant outcomes (mortality, liver related morbidity, quality of life) were not reported. CONCLUSION: Oral zinc supplementation improved performance on the number connection test, but no evidence about other clinical or biochemical outcomes was available.

High coffee intake is associated with lower grade nonalcoholic fatty liver disease: the role of peripheral antioxidant activity.

BACKGROUND & AIMS: Some phytochemicals present in coffee have a potential antioxidant role which seems to protect the human body against cardiovascular diseases, liver disease and malignancies. Nonalcoholic fatty liver disease is a common disease with limited therapeutic options. This study investigated the antioxidant effect of coffee by measuring antioxidant enzymes and lipid peroxidation markers in patients with nonalcoholic fatty liver disease. MATERIAL AND METHODS: We performed a case-control study at the University Hospital, Mexico City. Anthropometric, metabolic, dietary and biochemical variables of all patients were determined and compared. The presence of nonalcoholic fatty liver disease was established by ultrasonography. All patients completed a dietary questionnaire in order to determine their of coffee consumption. Catalase, superoxide dismutase and thiobarbituric acid reactive substances were measured in all of the patients. RESULTS: Seventy-three subjects with and 57 without nonalcoholic fatty liver disease were included. Patients with nonalcoholic fatty liver disease had significantly higher body mass index, blood glucose, homeostasis model of assessment-insulin resistance and insulin values in comparison to patients without nonalcoholic fatty liver disease. On the one hand, there was a significant difference in coffee intake between the groups (p < 0.05, for all comparisons). There was no significant difference between groups in catalase (0.39 ± 0.74 vs. 0.28 ± 0.69 nM/min/mL), superoxide dismutase (5.4 ± 3.45 vs. 4.7 ± 2.1 U/mL) or thiobarbituric acid-reactive substances (4.05 ± 1.87 vs. 3.94 ± 1.59 µM/mL). CONCLUSIONS: A high intake of coffee has a protective effect against nonalcoholic fatty liver disease however there was no significant difference in the antioxidant variables analyzed.

Sorafenib, a systemic therapy for hepatocellular carcinoma.

Hepatocellular carcinoma is a lethal disease that requires a multidisciplinary approach and management. Surgical therapy offers long-term survival; however, few patients are candidates. There has been no accepted systemic therapy for this disease until recently. This article briefly discusses the role of RAS/RAF/MEK/ERK signaling pathway in the pathogenesis of the disease and the promising role of sorafenib for advanced disease.