Ana Paula L. Moreira

Presence of synthetic pharmaceuticals as adulterants in slimming phytotherapeutic formulations and their analytical determination

Obesity that is associated with a high consumption of slimming substances is considered a public health problem around the world. In this context, the increasing consumption of phytotherapeutic formulations as alternative obesity treatments has revealed the presence of synthetic pharmaceuticals as adulterants. The illegally added adulterants are frequently anorexic, anxiolytic, and antidepressant pharmaceuticals. This review aims to describe the analytical methodologies utilized for the determination of adulterants in slimming phytotherapeutic formulations. Furthermore, this review describes some important adulteration cases, which occurred mainly in Europe, Asia, Brazil, and the USA.

Ischemia-modified albumin as an oxidative stress biomarker in obesity.

OBJECTIVE We evaluated the levels of ischemia-modified albumin (IMA) and its association with body mass index (BMI) in patients who are obese. DESIGN AND METHODS Fasting glucose, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, malondialdehyde, and IMA levels were assessed in 148 subjects. RESULTS IMA, malondialdehyde, and fasting glucose levels were significantly higher while the HDL cholesterol levels were lower in obese population. CONCLUSIONS IMA levels increase in overweight and obese subjects.

A new approach to determining pharmacologic adulteration of herbal weight loss products

Pharmaceutical adulterants are commonly found in herbal weight loss products, and analytical techniques for detecting these adulterants have become increasingly important to the public health community. Previously we reported a novel analytical method for the determination of adulterants in herbal formulations by capillary electrophoresis with contactless conductivity detection. The current study refines this previously described technique by testing if anxiolytics, diuretics, and laxatives interfered with the detection of anorectics and antidepressants. A survey of herbal weight loss products sold by compounding pharmacies in Brazil were analysed to determine the presence of pharmaceutical adulterants. A total of 106 herbal products, collected from 73 pharmacies in nine Brazilian states, were analysed for amfepramone, sibutramine, fenproporex, fluoxetine, paroxetine, sertraline and bupropion using the new analytical method. The method permitted the rapid and selective screening for the seven adulterants. Of the 106 weight loss products sampled, four (3.8%) were found to be adulterated by fenproporex or sibutramine. The adulterated samples were compounded by four different pharmacies located in three different Brazilian states. The novel capillary electrophoresis method we developed may be a useful tool for public health organisations tasked with analysing herbal weight loss products.

Blood thioredoxin reductase activity, oxidative stress and hematological parameters in painters and battery workers: relationship with lead and cadmium levels in blood

Oxidative stress has been shown to be involved in lead and cadmium toxicity. We recently showed that the activity of the antioxidant enzyme thioredoxin reductase (TrxR) is increased in the kidneys of lead‐exposed rats. The present study evaluated the blood cadmium and blood lead levels (BLLs) and their relationship with hematological and oxidative stress parameters, including blood TrxR activity in 50 painters, 23 battery workers and 36 control subjects. Erythrocyte δ‐aminolevulinate dehydratase (δ‐ALA‐D) activity and its reactivation index were measured as biomarkers of lead effects. BLLs increased in painters, but were even higher in the battery workers group. In turn, blood cadmium levels increased only in the painters group, whose levels were higher than the recommended limit. δ‐ALA‐D activity was inhibited only in battery workers, whereas the δ‐ALA‐D reactivation index increased in both exposed groups; both parameters were correlated to BLLs (r = −0.59 and 0.84, P < 0.05), whereas the reactivation index was also correlated to blood cadmium levels (r = 0.27, P < 0.05). The changes in oxidative stress and hematological parameters were distinctively associated with either BLLs or blood cadmium levels, except glutathione‐S‐transferase activity, which was correlated with both lead (r = 0.34) and cadmium (r = 0.47; P < 0.05). However, TrxR activity did not correlate with any of the metals evaluated. In conclusion, blood TrxR activity does not seem to be a good parameter to evaluate oxidative stress in lead‐ and cadmium‐exposed populations. However, lead‐associated changes in biochemical and hematological parameters at low BLLs underlie the necessity of re‐evaluating the recommended health‐based limits in occupational exposure to this metal. Copyright

Determination of diuretics and laxatives as adulterants in herbal formulations for weight loss

A new method is described for the determination of the most common diuretic and laxative adulterants found in formulations of anorexics and antidepressants. The method is based on the separation of furosemide, hydrochlorothiazide, chlorthalidone and amiloride (diuretics), phenolphthalein (laxative), amfepramone (anorexic) and fluoxetine and paroxetine (antidepressants) by capillary zone electrophoresis with capacitively coupled contactless conductivity detection. The method showed a precision ranging from 1.9% to 6.9% for a concentration of 25 mg/L, 0.6% to 5.3% for a concentration of 50 mg/L and 1.6% to 6.0% for a concentration of 100 mg/L for all analytes. The accuracy was 99% for amiloride, 102% for chlorthalidone, 101% for hydrochlorothiazide, 101% for furosemide, 94% for phenolphthalein, 105% for fluoxetine, 114% for paroxetine and 117% for amfepramone. The method allowed the drugs to be determined in the formulations at concentrations higher than 5.1 mg/kg for amiloride, 7.7 mg/kg for chlorthalidone, 6.8 mg/kg for hydrochlorothiazide, 10.7 mg/kg for furosemide, 8.4 mg/kg for phenolphthalein, 11.0 mg/kg for fluoxetine, 9.4 mg/kg for paroxetine and 11.0 mg/kg for amfepramone. Three of the 26 analysed herbal formulations were found to be adulterated (not declared on the label) with the diuretic hydrochlorothiazide. Five other samples contained diuretics declared on the label on the formulation. Thus, a total of eight samples, which were marketed as natural products, contained diuretics (declared or not) on the formulation.

Association Among Microalbuminuria and Oxidative Stress Biomarkers in Patients With Type 2 Diabetes

Aim Hyperglycemia in diabetes mellitus (DM) may be one of the most important factors responsible for the development of oxidative stress, which promotes the main complications in DM patients. Therefore, this study evaluated if the hyperglycemia could be related to oxidative stress biomarkers, lipid profile, and renal function in type 2 diabetes patients without clinic complications. Methods Plasmatic malondialdehyde (MDA), serum protein carbonyl (PCO), serum creatinine levels, microalbuminuria, glycated hemoglobin, and lipid profile were analyzed in 37 type 2 diabetic patients and 25 subjects with no diabetes. Results Serum creatinine levels were within the reference values, but microalbuminuria presented increased levels in all the patients compared with controls (P < 0.05) and above of the reference values. The MDA, PCO, low-density lipoprotein, and triglyceride levels showed positive correlation with microalbuminuria levels. Moreover, glycated hemoglobin presented positive correlation with MDA, PCO, and microalbuminuria levels. Conclusions The hyperglycemia could be responsible for the increase of the microalbuminuria levels and for the oxidation process in lipids and proteins in DM patients. Therefore, we suggested that the microvascular lesion is a direct consequence from hyperglycemia and an indirect one from the increased oxidative stress. Malondialdehyde and protein carbonyl levels could be suggested as additional biochemical evaluation to verify tissue damage in type 2 DM patients.

Capillary electrophoretic methods for the screening and determination of pharmacologic adulterants in herbal-based pharmaceutical formulations

This review aims to describe the CE methods utilized for the determination of adulterants in herbal‐based formulations marketed for different therapeutic purposes. The CE methods for screening and determination of pharmacologic adulterants are reviewed on the basis of the CE techniques and their detection methods. CZE and MEKC methods coupled to optical (UV), capacitively coupled contactless conductivity, and MS detection modes are discussed and reviewed. Worldwide adulteration cases related to pharmaceutical formulations containing herbs as the main active products are presented covering all the works published in the last four decades.

Simultaneous analysis of antihypertensive drugs and diuretics as adulterants in herbal-based products by ultra-high performance liquid chromatography-electrospray tandem mass spectrometry

The world consumption of herbal-based products has increased substantially for the treatment, prevention and cure of certain diseases. However, ineffective control of the available products has been contributing to the marketing of products sold as “natural”, which often contain illegally synthetic drugs as declared or non-declared components. It has been a common practice especially regarding drugs for treating chronic diseases, such as hypertension. In order to investigate herbal-based formulations with the claim of hypotensive activity, we developed an analytical method using ultra-high performance liquid chromatography-electrospray tandem mass spectrometry (UHPLC-ESI-MS/MS) for simultaneous determination of 13 antihypertensive drugs including diuretics, β-blockers, angiotensin II receptor antagonist and angiotensin converting enzyme inhibitors. Separation was accomplished in 6 minutes using a Zorbax® SB-C18 column using methanol and acetic acid 0.1% as the mobile phase. Limits of detection ranged from 0.02 to 2.51 μg L−1 and accuracy from 80.56 to 111.28%. A simple extraction procedure was used in the pretreatment step by dissolving the samples in 100% methanol followed of a 1000-fold dilution in the mobile phase and filtration through a Teflon membrane (0.2 μm). No adulterants were detected in the formulations as non-declared drugs. However, five samples contained the diuretics hydrochlorothiazide and furosemide as declared on the label. Quantification of diuretics in these samples revealed doses above and below the recommended dose for furosemide and hydrochlorothiazide.

Treatment with N-acetylcysteine does not alter blood glucose levels and the oxidative stress status in diabetic rats

Objectives: To verify the contribution of N-acetylcysteine (NAC) as an antioxidant drug in the therapy of diabetes, helping to reduce the deleterious effects resulting from oxidative stress associated with the hyperglycemic state. Materials and Methods: The animals were divided into normal (saline, 25 mg/kg NAC, and 75 mg/kg NAC) and diabetic rats (saline, 25 mg/kg NAC, and 75 mg/kg NAC) with five rats per group, and were treated or four weeks. Diabetes induction was performed by intraperitoneal injection of alloxan after fasting for 12 hours. Subsequently, glucose solution was used to promote wear of the pancreatic beta cells. Blood parameters such as glucose, glycated hemoglobin, hepatic and renal biomarkers, and butyrylcholinesterase activity were determined by commercial kits. Catalase, glutathione peroxidase, and superoxide dismutase activities were measured using spectrophotometric techniques, while glutathione and malondialdehyde levels were determined by chromatographic techniques. Results: NAC had no significant differences on glycemic, hepatic, renal, and oxidative stress biomarkers. Superoxide dismutase activity was significantly higher ( P < 0.05) in diabetic rats treated with NAC compared to the diabetic saline group, while butyrylcholinesterase activity was significantly lower ( P < 0.05) in the same groups. There was a negative correlation between superoxide dismutase and butyrylcholinesterase activities. Conclusion: NAC supplementation did not re-establish the antioxidant system and consequently the deleterious effects of diabetes did not decrease. Diabetic groups that received NAC demonstrated that superoxide dismutase activity was indirectly linked to the levels of butyrylcholinesterase. More studies are necessary to investigate the action of NAC on superoxide dismutase and butyrylcholinesterase activities in the diabetic state.