Current use of medicinal plants for children's diseases among mothers in Southern Romania.

There is a limited number of studies focusing on ethnomedical practices in children, particularly in Eastern Europe. Romania has a rich history of using medicinal plants in ethnopediatric care, and our objective was to identify the medicinal plants currently employed in treating childhood illnesses in the southern region of the country. Material and methods Our investigation used structured interviews, focusing on respondent demographics, local names of therapeutically employed herbs, the specific plant part(s) utilized, methods of preparation and administration, and local folk indications of taxa. A total of 326 mothers with children aged 0 to 18, hospitalized in the "Grigore Alexandrescu" Children Emergency Hospital Bucharest and residing in Southern Romania, were enrolled in the study. Use Value Citation Index (UVc), Informant Consensus Factor (Fic), and Fidelity Level (FL) were calculated. Results Twenty-five plants were identified for treating children's diseases in Southern Romania. The majority of informants resided in urban areas, and mothers primarily acquired knowledge from family members and healthcare professionals. The herbs most frequently employed were Mentha spp. (UV = 0.509) for diarrhea, Matricaria spp. (UV = 0.301) for skin infections (Fic = 0.99) and digestive diseases (Fic = 0.98), and Calendula officinalis L. (UV = 0.365) for skin diseases (Fic = 0.99). Less utilized were Raphanus raphanistrum subsp. sativus (L.) Domin in respiratory diseases, Prunus avium (L.) L. stalks in urinary tract ailments, Helianthus annuus L. in ear infections, Allium sativum L. in intestinal parasitosis, Viola tricolor L. in hives, Triticum aestivum L. in dermatitis and Allium ursinum L. as a tonic. In 184 cases herbal treatment was used in conjunction with conventional medications. Education level correlated with the number of employed plants and the variety of treated ailments, while residency (rural vs. urban) did not. Both residency and education influenced plant procurement methods: rural background and, surprisingly, higher education were linked to a preference for harvesting rather than purchasing plants. Conclusion Botanical remedies are still commonly used in the treatment of pediatric diseases in Southern Romania, although the variety of taxa seems reduced compared to the past. Further exploration is essential to unlock the maximum benefits of ethnopediatric practices.

L-Arginine-Dependent Nitric Oxide Production in the Blood of Patients with Type 2 Diabetes: A Pilot, Five-Year Prospective Study.

Backgound: Type 2 diabetes mellitus (T2DM) is a major cardiovascular risk factor. Nitric oxide (NO) is one of the many molecules that regulate vascular tone, and red blood cells (RBCs) are known to play an important role in adjusting cardiac function through NO export from RBCs. Our study prospectively investigated the L-arginine (L-arg)-nitric oxide (NO) metabolic pathway in the erythrocytes and plasma of subjects with T2DM. Methods: RBCs and plasma were collected from patients with T2DM (n = 10), at first clinical onset (baseline) and after five years of disease evolution (follow-up). L-arg content was assayed by competitive enzyme-linked immunoassay. Arginase activity and nitrate/nitrite levels were measured using spectrophotometry. Results: When compared to baseline, L-arg content decreased in RBCs and remained similar in the plasma; NO production decreased in RBCs and the plasma; and arginase activity was lower in RBCs and increased in plasma. Conclusions: The L-arg/NO metabolic pathway decreases in the RBCs of patients with T2DM five years after the first clinical onset. The persistent decrease in RBCs' arginase activity fails to compensate for the sustained decrease in RBCs' NO production in the diabetic environment. This pilot study indicates that the NO-RBC pool is depleted during the progression of the disease in the same cohort of T2DM patients.

Relevance of Phytochemical Taste for Anti-Cancer Activity: A Statistical Inquiry.

Targeting inflammation and the pathways linking inflammation with cancer is an innovative therapeutic strategy. Tastants are potential candidates for this approach, since taste receptors display various biological functions, including anti-inflammatory activity (AIA). The present study aims to explore the power different tastes have to predict a phytochemical's anti-cancer properties. It also investigates whether anti-inflammatory phytocompounds also have anti-cancer effects, and whether there are tastes that can better predict a phytochemical's bivalent biological activity. Data from the PlantMolecularTasteDB, containing a total of 1527 phytochemicals, were used. Out of these, only 624 phytocompounds met the inclusion criterion of having 40 hits in a PubMed search, using the name of the phytochemical as the keyword. Among them, 461 phytochemicals were found to possess anti-cancer activity (ACA). The AIA and ACA of phytochemicals were strongly correlated, irrespective of taste/orosensation or chemical class. Bitter taste was positively correlated with ACA, while sweet taste was negatively correlated. Among chemical classes, only flavonoids (which are most frequently bitter) had a positive association with both AIA and ACA, a finding confirming that taste has predictive primacy over chemical class. Therefore, bitter taste receptor agonists and sweet taste receptor antagonists may have a beneficial effect in slowing down the progression of inflammation to cancer.

Bitter Phytochemicals as Novel Candidates for Skin Disease Treatment.

Skin diseases represent a global healthcare challenge due to their rising incidence and substantial socio-economic burden. While biological, immunological, and targeted therapies have brought a revolution in improving quality of life and survival rates for certain dermatological conditions, there remains a stringent demand for new remedies. Nature has long served as an inspiration for drug development. Recent studies have identified bitter taste receptors (TAS2Rs) in both skin cell lines and human skin. Additionally, bitter natural compounds have shown promising benefits in addressing skin aging, wound healing, inflammatory skin conditions, and even skin cancer. Thus, TAS2Rs may represent a promising target in all these processes. In this review, we summarize evidence supporting the presence of TAS2Rs in the skin and emphasize their potential as drug targets for addressing skin aging, wound healing, inflammatory skin conditions, and skin carcinogenesis. To our knowledge, this is a pioneering work in connecting information on TAS2Rs expression in skin and skin cells with the impact of bitter phytochemicals on various beneficial effects related to skin disorders.

Phytochemicals and Inflammation: Is Bitter Better?

The taste of a herb influences its use in traditional medicine. A molecular basis for the taste-based patterns ruling the distribution of herbal (ethno) pharmacological activities may not be excluded. This study investigated the potential correlations between the anti-inflammatory activity (AIA) and the phytocompound taste and/or its chemical class. The study relies on information gathered by an extensive literature (articles, books, databases) search and made public as PlantMolecularTasteDB. Out of a total of 1527 phytotastants with reliably documented taste and structure available in PlantMolecularTasteDB, 592 (for each of which at least 40 hits were found on PubMed searches) were included in the statistical analysis. A list of 1836 putative molecular targets of these phytotastants was afterwards generated with SwissTargetPrediction tool. These targets were systematically evaluated for their potential role in inflammation using an international databases search. The correlations between phytochemical taste and AIA, between chemical class and AIA, and between the taste and the number of inflammation related targets were statistically analyzed. Phytochemical taste may be a better predictor of AIA than the chemical class. Bitter phytocompounds have a higher probability of exerting AIA when compared with otherwise phytotastants. Moreover, bitter phytotastants act upon more inflammation related targets than non-bitter tasting compounds.

Concentration of heavy metals and rare earth elements in patients with brain tumours: Analysis in tumour tissue, non-tumour tissue, and blood.

Inorganic elements have been associated with brain tumours for long. The blood concentration of 47 elements was assessed by ICP-MS in 26 brain tumour patients and 21 healthy subjects from Bucharest (Romania). All 47 elements were detected in the brain tumour tissue, and 22 were detected in > 80% of samples; this implies that these elements can cross the blood-brain barrier. Median blood levels of cadmium, lead, and nickel were higher than the reference values (1.14, 53.3, and 2.53 ng/mL). Gadolinium and tantalum showed significantly higher concentrations among cases. We observed considerable differences and different profiles of the presence of inorganic elements between the tumour and non-tumour brain tissue and between tissue from the primary tumour and tissue from brain metastasis. Our data suggest that similar to heavy metals, other elements - commonly used in high tech devices and rare earth elements - can also influence brain tumour.

Classic and targeted anti-leukaemic agents interfere with the cholesterol biogenesis metagene in acute myeloid leukaemia: Therapeutic implications.

Despite significant advances in deciphering the molecular landscape of acute myeloid leukaemia (AML), therapeutic outcomes of this haematological malignancy have only modestly improved over the past decades. Drug resistance and disease recurrence almost invariably occur, highlighting the need for a deeper understanding of these processes. While low O2 compartments, such as bone marrow (BM) niches, are well-recognized hosts of drug-resistant leukaemic cells, standard in vitro studies are routinely performed under supra-physiologic (21% O2 , ambient air) conditions, which limits clinical translatability. We hereby identify molecular pathways enriched in AML cells that survive acute challenges with classic or targeted therapeutic agents. Experiments took into account variations in O2 tension encountered by leukaemic cells in clinical settings. Integrated RNA and protein profiles revealed that lipid biosynthesis, and particularly the cholesterol biogenesis branch, is a particularly therapy-induced vulnerability in AML cells under low O2 states. We also demonstrate that the impact of the cytotoxic agent cytarabine is selectively enhanced by a high-potency statin. The cholesterol biosynthesis programme is amenable to additional translational opportunities within the expanding AML therapeutic landscape. Our findings support the further investigation of higher-potency statin (eg rosuvastatin)-based combination therapies to enhance targeting residual AML cells that reside in low O2 environments.

Historical ethnobotanical review of medicinal plants used to treat children diseases in Romania (1860s-1970s).

BACKGROUND: Romanian ethnopediatrics has a long history of medicinal plant use. The main objective of the present review was to identify, collect, systematize, and prioritize the available bibliographical data related to medicinal plants traditionally used to treat various pediatric diseases in Romania during the 1860s-1970s. METHODS: Information was mainly obtained by manual systematic search in various relevant historical works focused on the traditional use of medicinal plants in Romania (1860s-1970s), found in the Archives of Romanian Academy Library and National Romanian Library. RESULTS: A total of 153 medicinal plants belonging to 52 families were identified as having ethnopediatric significance. The plant traditional indications, targeted body systems, parts used, and way of administration were provided. We have also proposed one index (expressed as percentage) in order to assess the ethnopediatric applicability area of species: ethnopediatric relative therapeutic versatility (ERTV), which was calculated on the basis of the number of distinct uses mentioned for a species. The species identified to have the highest ERTV scores were Dryopteris filix-mas (100%), Gratiola officinalis (85.71%), Allium sativum (71.42%), Eryngium planum (71.42%), Juglans regia (71.42%), Matricaria chamomilla (71.42%), Plantago major (71.42%). CONCLUSIONS: The present study exposed for the first time to the international scientific community important ethnopediatric information contained in several local Romanian bibliographical resources that could guide the local and international researchers towards new directions of plant valorization.

Serum concentration of toxic metals and rare earth elements in children and adolescent.

Biomonitoring studies are important for quantifying the body burden of pollutants and their possible effects on health. Serum concentration of 42 elements was assessed by ICP-MS in 89 children (7.2 ± 3.4 years old) from Bucharest (Romania). Levels of pollutants were compared with the clinical data obtained from routine blood tests. Clinical parameters were in the physiological range. Deficiencies of manganese, selenium, and zinc were discovered. Blood levels of elements were low. The highest levels were observed among children younger than six years. The sum of iron, selenium, barium, nickel, antimony, and cerium was positively associated with hemoglobin (Spearman rho = 0.217, P-value = 0.041), while the sum of copper, thallium, niobium, and tantalum was negatively associated (Spearman rho = -0.228, P-value = 0.032). Given the inherent sensitivity of the child population, additional studies are needed to assess the effects of these elements on their health.

PhytoMolecularTasteDB: An integrative database on the "molecular taste" of Indian medicinal plants.

PhytoMolecularTaste database (PhytoMolecularTasteDB) described in the present work is related to the article "Main phytocompunds׳ tastes: a better predictor for the ethnopharmacological activities of medicinal plant than the phytochemical class?" (Dragos and Gilca, 2018) [1]. It includes a comprehensive list of plant derived tastants, as well as details on the "phyto-molecular taste" (PMT) (the combination of tastes resulted from the main tastants found in a medicinal plant). To collect the data, we searched publications in various databases and journals by using relevant keywords. Wherever necessary, manual search of lacking information was also performed in several books. We then extracted the reported phytoconstituents and PMT of all the ayurvedic medicinal plants included in DB. Data were compiled in Excel. In total, PhytoMolecularTasteDB includes 431 ayurvedic medicinal plants, 94 EPAs, 223 phytochemical classes, and 438 plant-derived tastants.

Traditional and ethnobotanical dermatology practices in Romania and other Eastern European countries.

The geographic and ecologic specificity of Romania and other Eastern European countries has resulted in the development of an exceptional diversity of medicinal plants. The purpose of this study was to provide an overview of the ethnobotanical dermatology practices based on the use of medicinal plants in this region. The indications, ethnopharmacologic activities, parts used, and administration of 106 medicinal plants are provided. We also discuss the relative importance of these species, using two modified indices of quantitative ethnobotany: Use Value Index and Relative Dermatologic Importance, which were calculated on the basis of etic constructions (indications and ethnopharmacologic activities). The species identified to have the highest dermatologic importance (on a scale of 100) were Brassica oleracea L. (100), Matricaria chamomilla L. (79.17), Arctium lappa L. (74.82), Daucus carota L. (72.28), Equisetum arvense L. (70.47), Juglans regia L. (69.93), Populous nigra L. (65.94), Symphytum officinale L. (63.59), Chelidonium majus L. (57.78), Calendula officinalis L. (57.78), Achillea millefolium L. (57.43), Melilotus officinalis L. (55.25), Allium cepa L. (51.45), Quercus robur L. (51.08), and Betula spp. (50.91). This preliminary study on ethnobotanical dermatology practices indicates that Eastern European traditional medical knowledge represents an important heritage that is currently underexploited.

Taste of phytocompounds: A better predictor for ethnopharmacological activities of medicinal plants than the phytochemical class?

ETHNOPHARMACOLOGICAL RELEVANCE: Understanding the patterns that shape traditional medical knowledge is essential for accelerating ethnopharmacological progress. According to Ayurveda, medicinal plants that belong to different taxa, but which have similar taste, may display similar (ethno)pharmacological activities (EPAs) (Bhishagratna, 1998; Sharma and Dash, 2006). AIM OF THE STUDY: To understand the patterns that govern the distribution of herbal EPAs in Ayurveda and to evaluate the potential concordance between chemical class or taste of the constituent phytocompounds and EPAs. MATERIAL AND METHODS: A mixed database (PhytoMolecularTasteDB) was constructed for Ayurvedic medicinal plants by integrating modern data (medicinal plant composition, phytochemical taste) with traditional data (ethnopharmacological activities of plant). PhytoMolecularTasteDB contains 431 Ayurvedic medicinal plants, 94 EPAs, 223 chemical classes of phytocompounds and 438 herbal tastants. Potential global or individual associations between chemical classes/taste of the phytoconstituents and EPAs were statistically analyzed. RESULTS: There was no global statistical correlation between the various chemical classes of phytocompounds and EPAs, although there were several individual correlations. The results suggest the existence of a global statistical correlation (besides several individual correlations) between the plant "molecular taste" (various taste-based classes of phytocompounds) and EPAs. CONCLUSIONS: These results suggest that phytochemical taste may be more relevant than chemical class for EPAs prediction.

Phytoceuticals in Acute Pancreatitis: Targeting the Balance between Apoptosis and Necrosis.

Despite recent advances in understanding the complex pathogenesis of pancreatitis, the management of the disease remains suboptimal. The use of phytoceuticals (plant-derived pleiotropic multitarget molecules) represents a new research trend in pancreatology. The purpose of this review is to discuss the phytoceuticals with pancreatoprotective potential in acute pancreatitis and whose efficacy is based, at least in part, on their capacity to modulate the acinar cell death. The phytochemicals selected, belonging to such diverse classes as polyphenols, flavonoids, lignans, anthraquinones, sesquiterpene lactones, nitriles, and alkaloids, target the balance between apoptosis and necrosis. Activation of apoptosis via various mechanisms (e.g., inhibition of X-linked inhibitor of apoptosis proteins by embelin, upregulation of FasL gene expression by resveratrol) and/or inhibition of necrosis seem to represent the essential key for decreasing the severity of the disease. Apart from targeting the apoptosis/necrosis balance, the phytochemicals displayed other specific protective activities: inhibition of inflammasome (e.g., rutin), suppression of neutrophil infiltration (e.g., ligustrazine, resveratrol), and antioxidant activity. Even though many of the selected phytoceuticals represent a promising therapeutic alternative, there is a shortage of human evidence, and further studies are required to provide solid basis to justify their use in the treatment of pancreatitis.

Extraoral Taste Receptor Discovery: New Light on Ayurvedic Pharmacology.

More and more research studies are revealing unexpectedly important roles of taste for health and pathogenesis of various diseases. Only recently it has been shown that taste receptors have many extraoral locations (e.g., stomach, intestines, liver, pancreas, respiratory system, heart, brain, kidney, urinary bladder, pancreas, adipose tissue, testis, and ovary), being part of a large diffuse chemosensory system. The functional implications of these taste receptors widely dispersed in various organs or tissues shed a new light on several concepts used in ayurvedic pharmacology (dravyaguna vijnana), such as taste (rasa), postdigestive effect (vipaka), qualities (guna), and energetic nature (virya). This review summarizes the significance of extraoral taste receptors and transient receptor potential (TRP) channels for ayurvedic pharmacology, as well as the biological activities of various types of phytochemical tastants from an ayurvedic perspective. The relative importance of taste (rasa), postdigestive effect (vipaka), and energetic nature (virya) as ethnopharmacological descriptors within Ayurveda boundaries will also be discussed.

Phytomedicine in Joint Disorders.

Chronic joint inflammatory disorders such as osteoarthritis and rheumatoid arthritis have in common an upsurge of inflammation, and oxidative stress, resulting in progressive histological alterations and disabling symptoms. Currently used conventional medication (ranging from pain-killers to biological agents) is potent, but frequently associated with serious, even life-threatening side effects. Used for millennia in traditional herbalism, medicinal plants are a promising alternative, with lower rate of adverse events and efficiency frequently comparable with that of conventional drugs. Nevertheless, their mechanism of action is in many cases elusive and/or uncertain. Even though many of them have been proven effective in studies done in vitro or on animal models, there is a scarcity of human clinical evidence. The purpose of this review is to summarize the available scientific information on the following joint-friendly medicinal plants, which have been tested in human studies: Arnica montana, Boswellia spp., Curcuma spp., Equisetum arvense, Harpagophytum procumbens, Salix spp., Sesamum indicum, Symphytum officinalis, Zingiber officinalis, Panax notoginseng, and Whitania somnifera.

Taste of medicinal plants: A potential tool in predicting ethnopharmacological activities?

ETHNOPHARMACOLOGICAL RELEVANCE: Taste (rasa) is traditionally valued in Ayurveda as an important ethnopharmacological category, and reported to correlate with certain therapeutic activities (karman). The present paper endeavors to provide for the first time a type of mapping of ayurvedic ethnopharmacological space by the integration of medicinal plant taste-activity relationship (TA) data, originating from several traditional sources. MATERIAL AND METHODS: The present TA database included 183 ayurvedic medicinal plants, with their traditional description of taste and ethnophamacological actions (EPA). 111 plants had a unique taste, and 72 plants a combination of several tastes, consisting of one principal taste, and other 2-4 secondary tastes. 121 ethnopharmacological actions were considered. Potential global or individual associations between rasa and karman were statistically analyzed. RESULTS: We found a statistically significant global correspondence between the predominant plant taste and the ethnopharmacological activities (Chi-square test, p<0.05), and the following individual associations (Fisher exact test, p<0.05, positive association if lnOR >0, negative association if lnOR <0): bitter- 11 positive associations (lnOR 0.940 to 3.544) and 8 negative associations (lnOR -0.997 to -3.101), sweet- 14 positive associations (lnOR 0.839 to 3.132) and 20 negative associations (lnOR -0.962 to -3.270), pungent- 23 positive associations (lnOR 0.835 to 4.126) and 11 negative associations (lnOR -1.255 to -3.147), astringent- 7 positive associations (lnOR 1.099 to 3.813) and 7 negative associations (lnOR -1.076 to -2.631), sour- 7 positive associations (lnOR 1.128 to 4.664) and 1 negative association (lnOR -2.244). Among the 109 statistically significant associations, 24 were not traditionally mentioned, and only 4 were in opposition with the traditional ayurvedic sources. DISCUSSIONS: The present study confirms the traditional relationship rasa-karman and demonstrates that statistical models can be used to predict EPAs of medicinal plants depending on their taste. Integration of the ayurvedic concept of taste into ethnopharmacological research might reveal new facets of plant therapeutic potentials and provide a framework for developing a probabilistic approach to drug discovery that can be exploited to increase bioprospecting research efficacy.

Estimating the yin-yang nature of Western herbs: a potential tool based on antioxidation-oxidation theory.

BACKGROUND: One of the biggest obstacles to progress in traditional Chinese medicine (TCM) development in Western countries is the difficulty of applying the traditional concepts to the Western medicinal plants, which are not traditionally described in ancient literature. During recent years, new advances in the field of understanding Yin/Yang aspects from a modern bioscientific point of view have led to the conclusion that antioxidationoxidation concepts might mirror a Yin-Yang relationship. METHODS: This study was intended to integrate the Yin-Yang theory of the traditional Chinese medicine with modern antioxidation-oxidation theory, and to propose a biochemical tool based on redox parameters (e.g. antioxidant capacity, chemiluminescence-CL signal inducing capacity), usable for the classification of Western medicinal plants from Yin/Yang perspective. Trolox equivalent antioxidant capacity (TEAC) of six vegetal aqueous extracts (Symphitum officinalae (radix)-SYM, Inula helenium (radix)-INU, Calendula officinalis (flores)-CAL, Angelica arhanghelica (folium)ANG(F), Angelica arhanghelica (radix)-ANG(R), Ecbalium Elaterium (fruits)-ECB) and luminol-enhanced chemiluminescence of PMNL on addition of these vegetal extracts were measured. Percentages from the maximal or minimal values obtained were calculated for each extract (TEAC%, PMNL stimulation%, PMNL inhibition%, relative speed of action% (RSA%%)), specific Yin-Yang significance was assigned to each relative parameter. In the end, an integration of all the relative values was done, in order to find a global "Yin" or a "Yang" trait of each vegetal extract. RESULTS: TEAC decreased in the following order: SYM > INU > CAL >ANG(F) > ANG(R > ECB. Three vegetal extracts (SYM > INU > ECB) decreased the luminol-enhanced chemiluminescence of PMNL, two (ANG(R) > ANG(F)) increased it, while one (CAL) had a dual effect. After the integration of the percentages, CAL was found to have a global "Yang" trait, while the rest of the plants had a global "Yin" trait. CONCLUSIONS: TEAC% and PMNL inhibition% appears to correlate with the Yin properties of herbs, while PMNL stimulation% and RSA% might correlate with Yang aspects within the formal TCM classification system, and may be useful criteria in describing the Western herbs from a TCM point of view.

A study of antioxidant activity in patients with schizophrenia taking atypical antipsychotics.

INTRODUCTION: Atypical antipsychotics have significantly improved the quality of life for schizophrenic patients. Despite their beneficial effects, these antipsychotics induce weight gain, diabetes, and dyslipidemia. The aims of this study were to investigate the antioxidative activity of paraoxonase and assess lipid profile as a cardiovascular risk factor in patients with schizophrenia under long-term clozapine or risperidone treatment. METHODS: The study included 66 patients with schizophrenia under clozapine or risperidone treatment and 19 healthy control subjects. Serum paraoxonase activities against paraoxon (PON(PO)), phenylacetate (PON(PA)), dihydrocoumarin (PON(DHC)), serum Trolox equivalent antioxidant activity (TEAC), antioxidant gap (GAP), and lipid profile were determined. RESULTS: PON(DHC) activity was reduced in both antipsychotic drug-treated groups (clozapine 43.46 ± 1.06 U/ml, p < 0.001; risperidone 50.57 ± 1.54 U/ml, p < 0.01; control 52.27 ± 1.34 U/ml). A similar pattern was observed for the PON(DHC)/HDL-cholesterol (HDLC) ratio. On the contrary, PON(PO) and PON(PA) were increased in the treated group, but the corresponding paraoxonase/HDLC ratios were not significantly different from controls, except for PON/HDLC in the clozapine group. TEAC and GAP were only decreased in the clozapine-treated group. CONCLUSIONS: In patients with schizophrenia, clozapine or risperidone treatment had different effects on various paraoxonase activities. The results of the present study suggest that patients with schizophrenia might be at increased risk for metabolic and cardiovascular disease related to reduced PON(DHC), TEAC, and GAP.

Erythrocyte membrane stability to hydrogen peroxide is decreased in Alzheimer disease.

The brain and erythrocytes have similar susceptibility toward free radicals. Therefore, erythrocyte abnormalities might indicate the progression of the oxidative damage in Alzheimer disease (AD). The aim of this study was to investigate erythrocyte membrane stability and plasma antioxidant status in AD. Fasting blood samples (from 17 patients with AD and 14 healthy controls) were obtained and erythrocyte membrane stability against hydrogen peroxide and 2,2'-azobis-(2-amidinopropane) dihydrochloride (AAPH), serum Trolox equivalent antioxidant capacity (TEAC), residual antioxidant activity or gap (GAP), erythrocyte catalase activity (CAT), erythrocyte superoxide dismutase (SOD) activity, erythrocyte nonproteic thiols, and total plasma thiols were determined. A significant decrease in erythrocyte membrane stability to hydrogen peroxide was found in AD patients when compared with controls (P<0.05). On the contrary, CAT activity (P<0.0001) and total plasma thiols (P<0.05) were increased in patients with AD compared with controls. Our results indicate that the most satisfactory measurement of the oxidative stress level in the blood of patients with AD is the erythrocyte membrane stability to hydrogen peroxide. Reduced erythrocyte membrane stability may be further evaluated as a potential peripheral marker for oxidative damage in AD.