Wild thyme (Thymus serpyllum L.): a review of the current evidence of nutritional and preventive health benefits.

Thymus serpyllum L. (Lamiaceae), known in English as 'wild thyme', is primarily found in the Palearctic realm (Eurasia, North Africa) and has been utilized traditionally for culinary, nutritional, medicinal, and aromatic purposes. The essential oil extracted from wild thyme is particularly noteworthy, being used extensively in the food industry as a flavoring agent and preservative. The plant's aerial parts are commonly employed as an element of the diet (e.g., tea)/for culinary uses and in local/traditional medicine (primarily for managing respiratory and gastrointestinal conditions), similar to the use of common thyme. There is practically no information available on the species' nutritional benefits. Pharmacological studies, including in vitro and in vivo research, alongside a limited number of clinical trials, have investigated extracts of Thymus serpyllum, although these extracts are often phytochemically poorly characterized in different experimental protocols and models. These studies have demonstrated a range of therapeutic effects, such as antimicrobial (notably the essential oil) and anti-inflammatory, as well as its preventative health benefits and nutritional value of wild thyme. Preclinical studies have corroborated the plant's anti-inflammatory potential, particularly in conditions like inflammatory bowel diseases (IBD) and irritable bowel syndromes (IBS). Additionally, evidence of hepatoprotective activities and benefits in managing metabolic syndrome and cardiovascular health issues, such as lipid metabolism regulation, cholesterol reduction, antidiabetic, antihypertensive, and immunomodulatory effects, have been observed predominantly in rodent models. Phytochemical analysis of wild thyme reveals an essential oil fraction below 1%, along with non-volatile compounds predominantly comprising phenolic acids (such as rosmarinic, salvianolic, and caffeic acids) and flavonoids (mainly glucosides of luteolin, apigenin, and their derivatives). These components are believed to contribute significantly to the plant's medicinal, nutritional, and preventive health properties. Despite promising findings, there is a need for more rigorously designed controlled clinical trials using phytochemically characterized wild thyme. The plant has an excellent safety and tolerability record. This review at the interface of nutritional/preventive health properties and as pharmacological activities highlights the current role of wild thyme in nutrition and general healthcare as well as its future potential, and also points to important gaps in the literature.

Development process of a clinical guideline to manage type 2 diabetes in adults by Ayurvedic practitioners.

Background: Type 2 diabetes mellitus (T2DM), a common chronic health condition, has major health and socioeconomic consequences. In the Indian subcontinent, it is a health condition for which individuals commonly consult Ayurvedic (traditional medical system) practitioners and use their medicines. However, to date, a good quality T2DM clinical guideline for Ayurvedic practitioners, grounded on the best available scientific evidence, is not available. Therefore, the study aimed to systematically develop a clinical guideline for Ayurvedic practitioners to manage T2DM in adults. Methods: The development work was guided by the UK's National Institute for Health and Care Excellence (NICE) manual for developing guidelines, the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach, and the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument. First, a comprehensive systematic review was conducted which evaluated Ayurvedic medicines' effectiveness and safety in managing T2DM. In addition, the GRADE approach was used for assessing the certainty of the findings. Next, using the GRADE approach, the Evidence-to-Decision framework was developed, and we focused on glycemic control and adverse events. Subsequently, based on the Evidence-to-Decision framework, a Guideline Development Group of 17 international members made recommendations on Ayurvedic medicines' effectiveness and safety in T2DM. These recommendations formed the basis of the clinical guideline, and additional generic content and recommendations were adapted from the T2DM Clinical Knowledge Summaries of the Clarity Informatics (UK). The feedback given by the Guideline Development Group on the draft version was used to amend and finalize the clinical guideline. Results: A clinical guideline for managing T2DM in adults by Ayurvedic practitioners was developed, which focuses on how practitioners can provide appropriate care, education, and support for people with T2DM (and their carers and family). The clinical guideline provides information on T2DM, such as its definition, risk factors, prevalence, prognosis, and complications; how it should be diagnosed and managed through lifestyle changes like diet and physical activity and Ayurvedic medicines; how the acute and chronic complications of T2DM should be detected and managed (including referral to specialists); and advice on topics like driving, work, and fasting including during religious/socio-cultural festivals. Conclusion: We systematically developed a clinical guideline for Ayurvedic practitioners to manage T2DM in adults.

Intestinal anti-inflammatory and visceral analgesic effects of a Serpylli herba extract in an experimental model of irritable bowel syndrome in rats.

Ethnopharmacological relevance: Serpylli herba extract (SHE), composed of the aerial parts of wild thyme (Thymus serpyllum L.) (Lamiaceae family), is traditionally used in Europe and North Africa to treat diarrhea, gastric ulcers, intestinal parasites and upper respiratory tract infections. Recently, SHE has generated a great interest for irritable bowel syndrome (IBS) management, probably due to its intestinal anti-inflammatory properties shown in experimental colitis and the fact that its active components could preserve the intestinal barrier integrity, which is altered in patients with IBS. Aim of study: We aimed to test the effects of a SHE in a rat experimental model resembling human IBS. Materials and methods: IBS was provoked by deoxycholic acid (DCA). Rats were then treated with SHE (100 mg/kg) or gabapentin (70 mg/kg) and different inflammatory and gut barrier integrity markers were evaluated. Moreover, several gut hypersensitivity and hyperalgesia determinations were performed. Results: SHE improved referred pain and visceral hypersensitivity. Additionally, SHE enhanced immune status by downregulating of the expression of the pro-inflammatory mediators Il-1ß, Il-6, Ifn-γ, Tlr-4, and the inducible enzyme Cox-2, thus inducing visceral analgesia, and promoting the restore of the gut barrier function by upregulating the mucins Muc-2 and Muc-3. These anti-inflammatory effects could be related to its action on mast cells since it significantly inhibited the ß-Hexosaminidase production in RBL-2H3 cells. Lastly, SHE also seems to modulate the serotonin pathway by restoring the altered expression of the 5-HT receptors Htr-3 and Htr-4. Conclusion: SHE could be considered a potential new treatment for IBS, since it ameliorates hypersensitivity, visceral hyperalgesia, and inflammation. These beneficial effects may be due to the inhibition of mast cells degranulation and serotonin pathway.

The Antioxidant Activity of Thymus serpyllum Extract Protects against the Inflammatory State and Modulates Gut Dysbiosis in Diet-Induced Obesity in Mice.

Nowadays, there is an increasing interest in alternative therapies in the treatment of metabolic syndrome that combine efficacy and safety profiles. Therefore, this study aimed to evaluate the effect of an extract of Thymus serpyllum, containing rosmarinic acid, on high-fat diet (HFD)-induced obesity mice, highlighting the impact of its antioxidant activity on the inflammatory status and gut dysbiosis. The extract was administered daily (50, 100 and 150 mg/kg) in HFD-fed mice. The treatment reduced body weight gain, glucose and lipid metabolic profiles. Moreover, the extract ameliorated the inflammatory status, with the c-Jun N-terminal kinases (JUNK) pathway being involved, and showed a significant antioxidant effect by the reduction of radical scavenging activity and the mitigation of lipid peroxidation. Moreover, the extract was able to modulate the altered gut microbiota, restoring microbial richness and diversity, and augmenting the counts of short-chain fatty acid producing bacteria, which have been associated with the maintenance of gut permeability and weight regulation. In conclusion, the antioxidant activity of Thymus serpyllum extract displayed a positive impact on obesity and its metabolic alterations, also reducing systemic inflammation. These effects may be mediated by modulation of the gut microbiota.

Acute and Chronic Effects of Green Oat (Avena sativa) Extract on Cognitive Function and Mood during a Laboratory Stressor in Healthy Adults: A Randomised, Double-Blind, Placebo-Controlled Study in Healthy Humans.

Green oat (Avena sativa) extracts contain several groups of potentially psychoactive phytochemicals. Previous research has demonstrated improvements in cognitive function following a single dose of these extracts, but not following chronic supplementation. Additionally, whilst green oat extracts contain phytochemicals that may improve mood or protect against stress, for instance species-specific triterpene saponins, to date this possibility has not been examined. The current study investigated the effects of a single dose and four weeks of administration of a novel, Avena sativa herbal extract (cognitaven®) on cognitive function and mood, and changes in psychological state during a laboratory stressor. The study adopted a dose-ranging, double-blind, randomised, parallel groups design in which 132 healthy males and females (35 to 65 years) received either 430 mg, 860 mg, 1290 mg green oat extract or placebo for 29 days. Assessments of cognitive function, mood and changes in psychological state during a laboratory stressor (Observed Multitasking Stressor) were undertaken pre-dose and at 2 h and 4 h post-dose on the first (Day 1) and last days (Day 29) of supplementation. The results showed that both a single dose of 1290 mg and, to a greater extent, supplementation for four weeks with both 430 mg and 1290 mg green oat extract resulted in significantly improved performance on a computerised version of the Corsi Blocks working memory task and a multitasking task (verbal serial subtractions and computerised tracking) in comparison to placebo. After four weeks, the highest dose also decreased the physiological response to the stressor in terms of electrodermal activity. There were no treatment-related effects on mood. These results confirm the acute cognitive effects of Avena sativa extracts and are the first to demonstrate that chronic supplementation can benefit cognitive function and modulate the physiological response to a stressor.

Calcium Pyruvate Exerts Beneficial Effects in an Experimental Model of Irritable Bowel Disease Induced by DCA in Rats.

Pyruvate is a normal constituent of the body that participates in carbohydrate metabolism and functions as a scavenger of free radicals. Calcium pyruvate monohydrate (CPM) is a more stable derivative that has proved its anti-inflammatory effect in experimental colitis, among other disorders, and that could also be considered a source of calcium. Thus, it would be useful for the treatment of diseases with an inflammatory component and a high prevalence of osteoporosis like the irritable bowel syndrome (IBS). The aim of the present study is to evaluate the effects of CPM in a rat model of chronic post-inflammatory visceral pain induced by deoxycholic acid (DCA) that resembles IBS. Rats were administered DCA for three days intracolonically and then treated daily with CPM (40 and 100 mg/kg) or gabapentin (70 mg/kg) (positive control) by oral gavage for 17 days. The treatments reduced the visceral hypersensitivity measured by response to colorectal distension and referred pain. DCA induced changes in the colonic immune response characterized by increased expression of the cytokine Il-1ß and the inducible enzyme Cox-2, which was reduced by the treatments. DCA also decreased the gut expression of the mucins Muc-2 and Muc-3, which was normalized by CPM, whereas gabapentin only increased significantly Muc-3. Moreover, DCA increased the expression of Tlr3, which was decreased to basal levels by all the treatments. However, the serotonin receptor Htr-4, which was also elevated, was not affected by any of the treatments, indicating no effect through this signalling pathway. In conclusion, CPM ameliorated the visceral hypersensitivity and the referred pain caused by DCA, being as effective as the control drug. Furthermore, it improved the immune status of the animals, which could contribute to the visceral analgesia and the regeneration of the intestinal epithelial barrier integrity.

The Acute and Chronic Cognitive and Cerebral Blood Flow Effects of a Sideritis scardica (Greek Mountain Tea) Extract: A Double Blind, Randomized, Placebo Controlled, Parallel Groups Study in Healthy Humans.

BACKGROUND: The presence of polyphenols such as hydroxy-cinnamic acids and flavonoids in Sideritis scardica (Greek mountain tea) are likely responsible for the cognitive and mood effects of its consumption and this could be underpinned by the ability of such polyphenols to prevent monoamine neurotransmitter reuptake and to increase cerebral blood flow (CBF). OBJECTIVE: The current study extends the small amount of Sideritis scardica literature in humans by assessing both cognitive and mood outcomes in a sample of older adults, as well as blood pressure (BP) and CBF, in a subsample, utilizing near-infrared spectroscopy (NIRS). DESIGN: This randomized, double-blind, placebo-controlled, parallel groups trial randomized N = 155, 50⁻70-year-old male and female participants who were assessed for the cognitive (N = 140), mood (N = 142), BP (N = 133) and CBF (N = 57) effects of two doses of Greek mountain tea (475 and 950 mg) as well as an active control of 240 mg Ginkgo biloba, and a placebo control, following acute consumption (Day 1) and following a month-long consumption period (Day 28). RESULTS: Relative to the placebo control, 950 mg Greek mountain tea evinced significantly fewer false alarms on the Rapid Visual Information Processing (RVIP) task on Day 28 and significantly reduced state anxiety following 28 days consumption (relative also to the active, Ginkgo control). This higher dose of Greek mountain tea also attenuated a reduction in accuracy on the picture recognition task, on Day 1 and Day 28, relative to Ginkgo and both doses of Greek mountain tea trended towards significantly faster speed of attention on both days, relative to Ginkgo. Both doses of Greek mountain tea, relative to placebo, increased oxygenated haemoglobin (HbO) and oxygen saturation (Ox%) in the prefrontal cortex during completion of cognitively demanding tasks on Day 1. The higher dose also evinced greater levels of total (THb) and deoxygenated (Hb) haemoglobin on Day 1 but no additional effects were seen on CBF on Day 28 following either dose of Greek mountain tea. Ginkgo biloba led to lower levels of Ox% and higher levels of Hb on Day 1 and lower levels of both HbO and THb on Day 28. CONCLUSIONS: The significantly improved cognitive performance following Greek mountain tea on Day 1 could be due to significant modulation of the CBF response. However, these improvements on Day 28 are more likely to be due to the reductions in state anxiety and, taken together, suggests that the former mechanism is more likely to facilitate acute cognitive effects and the latter more likely to underpin more prolonged cognitive improvements.

Assessment of the Acute and Subchronic Toxicity and Mutagenicity of Sideritis scardica Griseb. Extracts.

Sideritis scardica Griseb. has a long history of collection from the wild as a traditional remedy for respiratory and gastrointestinal complaints. It has also been investigated for its promising pharmacological activities in the central nervous system. However, its toxicological data is entirely missing. This study investigated the acute and repeated-dose oral toxicity of a S. scardica 20% (v/v) ethanol extract in Sprague Dawley rats, and mutagenicity using the Ames test. No gross pathological abnormalities and no toxicity signs or mortality were detected in animals treated with the dose of 2000 mg/kg bw during 14 days of observation. The tested extract was assigned to category 5 of the GHS. To evaluate a repeated-dose toxicity, an extract has been tested over a 28-day period followed by a 14-day recovery period. No mortality and no changes in body/organ weight or food consumption have been observed. The no-observed-adverse-effect-level of the extract was determined at 1000 mg/kg bw. The results of Ames tests conducted on extracts of different polarity (water; 20% (v/v) ethanol; 50% (v/v) ethanol; n-heptane), were unequivocally negative. The study reveals no toxicity of S. scardica and no concerns for its mutagenic effects, supports its positive safety profile, and confirms the acknowledged traditional medicinal use in human.

Single pyruvate intake induces blood alkalization and modification of resting metabolism in humans.

OBJECTIVES: Three separate studies were performed with the aim to 1) determine the effect of a single sodium pyruvate intake on the blood acid-base status in males and females; 2) compare the effect of sodium and calcium pyruvate salts and establish their role in the lipolysis rate; and 3) quantify the effect of single pyruvate intake on the resting energy metabolism. METHODS: In all, 48 individuals completed three separate studies. In all the studies, participants consumed a single dose of pyruvate 0.1 g/kg 60 min before commencing the measurements. The whole blood pH, bicarbonate concentration, base excess or plasma glycerol, free fatty acids, glucose concentrations, or resting energy expenditure and calculated respiratory exchange ratio were determined. The analysis of variance for repeated measurements was performed to examine the interaction between treatment and time. RESULTS: The single dose of sodium pyruvate induced blood alkalization, which was more marked in the male than in the female participants. Following the ingestion of sodium or calcium pyruvate, the blood acid-base parameters were higher than in the placebo trial. Furthermore, 3-h postingestion glycerol was lower in both pyruvate trials than in placebo. Resting energy expenditure did not differ between the trials; however, carbohydrate oxidation was increased after sodium pyruvate ingestion. CONCLUSION: Pyruvate intake induced mild alkalization in a sex-dependent fashion. Moreover, it accelerated carbohydrate metabolism and delayed the rate of glycerol appearance in the blood, but had no effect on the resting energy expenditure. Furthermore, sodium salt seems to have had a greater effect on the blood buffering level than calcium salt.

Hibiscus sabdariffa L. - a phytochemical and pharmacological review.

Hibiscus sabdariffa L. (Hs, roselle; Malvaceae) has been used traditionally as a food, in herbal drinks, in hot and cold beverages, as a flavouring agent in the food industry and as a herbal medicine. In vitro and in vivo studies as well as some clinical trials provide some evidence mostly for phytochemically poorly characterised Hs extracts. Extracts showed antibacterial, anti-oxidant, nephro- and hepato-protective, renal/diuretic effect, effects on lipid metabolism (anti-cholesterol), anti-diabetic and anti-hypertensive effects among others. This might be linked to strong antioxidant activities, inhibition of α-glucosidase and α-amylase, inhibition of angiotensin-converting enzymes (ACE), and direct vaso-relaxant effect or calcium channel modulation. Phenolic acids (esp. protocatechuic acid), organic acid (hydroxycitric acid and hibiscus acid) and anthocyanins (delphinidin-3-sambubioside and cyanidin-3-sambubioside) are likely to contribute to the reported effects. More well designed controlled clinical trials are needed which use phytochemically characterised preparations. Hs has an excellent safety and tolerability record.

Effects of short-term ingestion of Russian Tarragon prior to creatine monohydrate supplementation on whole body and muscle creatine retention and anaerobic sprint capacity: a preliminary investigation.

BACKGROUND: Extracts of Russian Tarragon (RT) have been reported to produce anti-hyperglycemic effects and influence plasma creatine (Cr) levels while supplementing with creatine monohydrate (CrM). The purpose of this preliminary study was to determine if short-term, low-dose aqueous RT extract ingestion prior to CrM supplementation influences whole body Cr retention, muscle Cr or measures of anaerobic sprint performance. METHODS: In a double-blind, randomized, and crossover manner; 10 recreationally trained males (20 ± 2 yrs; 179 ± 9 cm; 91.3 ± 34 kg) ingested 500 mg of aqueous RT extract (Finzelberg, Andernach, Germany) or 500 mg placebo 30-minutes prior to ingesting 5 g of CrM (Creapure®, AlzChem AG, Germany) twice per day for 5-days then repeated after a 6-week wash-out period. Urine was collected at baseline and during each of the 5-days of supplementation to determine urine Cr content. Whole body Cr retention was estimated from urine samples. Muscle biopsies were obtained for determination of muscle free Cr content. Participants also performed two 30-second Wingate anaerobic capacity tests prior to and following supplementation for determination of peak power (PP), mean power (MP), and total work (TW). Data were analysed by repeated measures MANOVA. RESULTS: Whole body daily Cr retention increased in both groups following supplementation (0.0 ± 0.0; 8.2 ± 1.4, 6.5 ± 2.4, 5.6 ± 3.2, 6.1 ± 2.6, 4.8 ± 3.2 g · d-1; p = 0.001) with no differences observed between groups (p = 0.59). After 3 and 5-days of supplementation, respectively, both supplementation protocols demonstrated a significant increase in muscle free Cr content from baseline (4.8 ± 16.7, 15.5 ± 23.6 mmol · kg-1 DW, p = 0.01) with no significant differences observed between groups (p = 0.34). Absolute change in MP (9 ± 57, 35 ± 57 W; p = 0.031), percent change in MP (2.5 ± 10.5, 6.7 ± 10.4%; p = 0.026), absolute change in TW (275 ± 1,700, 1,031 ± 1,721 J; p = 0.032), and percent change in TW (2.5 ± 10.5, 6.6 ± 10.4%; p = 0.027) increased over time in both groups with no differences observed between groups. CONCLUSIONS: Short-term CrM supplementation (10 g · d-1 for 5-days) significantly increased whole body Cr retention and muscle free Cr content. However, ingesting 500 mg of RT 30-min prior to CrM supplementation did not affect whole body Cr retention, muscle free Cr content, or anaerobic sprint capacity in comparison to ingesting CrM with a placebo.

Intestinal anti-inflammatory activity of the Serpylli herba extract in experimental models of rodent colitis.

INTRODUCTION: Nowadays, there is an increasing interest for alternative options in the treatment of inflammatory bowel diseases (IBDs) that combine efficacy and an adequate safety profile. METHODS: The intestinal anti-inflammatory effects of Serpylli herba, the officinal drug in the European Pharmacopeia composed by the aerial parts of wild thyme (Thymus serpyllum), were evaluated in the trinitrobenzenesulfonic acid (TNBS)-induced rat colitis and dextran sodium sulfate (DSS)-induced mouse colitis, which are well characterized experimental models with some resemblance to human IBD. RESULTS: S. herba extract exerted an intestinal anti-inflammatory effect in both experimental models of colitis, as evidenced both histologically, since it facilitated the tissue recovery of the damaged colon, and biochemically as showed by the improvement of the different inflammatory markers evaluated, including myeloperoxidase activity, glutathione content, and leukotriene B4 levels as well as the expression of the inducible proteins iNOS and COX-2. This beneficial effect was associated with the reduction in the expression of different cytokines, like TNFα, IL-1ß, IFNγ, IL-6 and IL-17, the chemokine MCP-1, and the adhesion molecule ICAM-1, thus ameliorating the altered immune response associated with the colonic inflammation. CONCLUSION: S. herba extract displays an anti-inflammatory effect on different models of rodent colitis that could be attributed to its immunomodulatory properties.

Ficus carica leaf extract modulates the lipid profile of rats fed with a high-fat diet through an increase of HDL-C.

Ficus carica has been traditionally used for the treatment of several metabolic syndrome-related health problems. It was the objective of this study to investigate the preventive effects of a Ficus carica (FC) leaf extract on hyperlipidemia in high fat diet (HFD)-induced obese male rats. Male Sprague-Dawley rats (180-200 g) were fed with a regular diet, HFD or a HFD + oral treatment of either 50 mg/kg or 100 mg/kg of FC or 30 mg/kg pioglitazone for six weeks. A range of parameters was evaluated including body weight development, plasma levels of total cholesterol, triglycerides (TG), low-density-lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C), adiponectin, leptin, glucose, insulin, interleukin-6 (IL-6), atherogenic index (AI) and the coronary risk index (CRI). FC significantly lowered TG and IL-6 levels and elevated HDL cholesterol (p < 0.05). The effects of FC on lipid parameters were more pronounced than those of the positive control pioglitazone. FC significantly lowered AI and CRI (p < 0.01) while it had no effect on adiponectin and leptin levels. Our results demonstrate that preventive treatment with FC significantly improved the lipid profile and decreased adipogenic risk factors in HFD rats most likely mediated through an increase in HDL-C levels.

Additive insulinogenic action of Opuntia ficus-indica cladode and fruit skin extract and leucine after exercise in healthy males.

BACKGROUND: Oral intake of a specific extract of Opuntia ficus-indica cladode and fruit skin (OpunDia™) (OFI) has been shown to increase serum insulin concentration while reducing blood glucose level for a given amount of glucose ingestion after an endurance exercise bout in healthy young volunteers. However, it is unknown whether OFI-induced insulin stimulation after exercise is of the same magnitude than the stimulation by other insulinogenic agents like leucine as well as whether OFI can interact with those agents. Therefore, the aims of the present study were: 1) to compare the degree of insulin stimulation by OFI with the effect of leucine administration; 2) to determine whether OFI and leucine have an additive action on insulin stimulation post-exercise. METHODS: Eleven subjects participated in a randomized double-blind cross-over study involving four experimental sessions. In each session the subjects successively underwent a 2-h oral glucose tolerance test (OGTT) after a 30-min cycling bout at ~70% VO2max. At t0 and t60 during the OGTT, subjects ingested 75 g glucose and capsules containing either 1) a placebo; 2) 1000 mg OFI; 3) 3 g leucine; 4) 1000 mg OFI + 3 g leucine. Blood samples were collected before and at 30-min intervals during the OGTT for determination of blood glucose and serum insulin. RESULTS: Whereas no effect of leucine was measured, OFI reduced blood glucose at t90 by ~7% and the area under the glucose curve by ~15% and increased serum insulin concentration at t90 by ~35% compared to placebo (P<0.05). From t60 to the end of the OGTT, serum insulin concentration was higher in OFI+leucine than in placebo which resulted in a higher area under the insulin curve (+40%, P<0.05). CONCLUSION: Carbohydrate-induced insulin stimulation post-exercise can be further increased by the combination of OFI with leucine. OFI and leucine could be interesting ingredients to include together in recovery drinks to resynthesize muscle glycogen faster post-exercise. Still, it needs to be confirmed that such nutritional strategy effectively stimulates post-exercise muscle glycogen resynthesis.

Opuntia ficus-indica ingestion stimulates peripheral disposal of oral glucose before and after exercise in healthy men.

The purpose of this study was to investigate the effect of Opuntia ficus-indica (OFI) cladode and fruit-skin extract on blood glucose and plasma insulin increments due to high-dose carbohydrate ingestion, before and after exercise. Healthy, physically active men (n = 6; 21.0 ± 1.6 years, 78.1 ± 6.0 kg) participated in a double-blind placebo-controlled crossover study involving 2 experimental sessions. In each session, the subjects successively underwent an oral glucose tolerance test at rest (OGTT(R)), a 30-min cycling bout at ~75% VO(2max), and another OGTT after exercise (OGTT(EX)). They received capsules containing either 1,000 mg OFI or placebo (PL) 30 min before and immediately after the OGTT(R). Blood samples were collected before (t0) and at 30-min intervals after ingestion of 75 g glucose for determination of blood glucose and serum insulin. In OGTT(EX) an additional 75-g oral glucose bolus was administered at t60. In OGTT(R), OFI administration reduced the area under the glucose curve (AUC(GLUC)) by 26%, mainly due to lower blood glucose levels at t30 and t60 (p < .05). Furthermore, a higher serum insulin concentration was noted after OFI intake at baseline and at t30 (p < .05). In OGTT(EX), blood glucose at t60 was ~10% lower in OFI than in PL, which resulted in a decreased AUC(GLUC) (-37%, p < .05). However, insulin values and AUC(INS) were not different between OFI and PL. In conclusion, the current study shows that OFI extract can increase plasma insulin and thereby facilitate the clearance of an oral glucose load from the circulation at rest and after endurance exercise in healthy men.

Comparative evaluation of two different Artemisia dracunculus L. cultivars for blood sugar lowering effects in rats.

Recent concerns about the potential carcinogenicity of estragole and methyleugenol led a number of regulatory bodies to call for restrictions on the use of herbs that contain these constituents. A number of medicinal plants produce essential oils that contain estragole and methyleugenol, including Artemisia dracunculus L. (tarragon). Previous studies have proven the antidiabetic properties of tarragon. In order to address the safety concerns of estragole containing tarragon extracts, an extraction procedure was developed to minimize the estragole and methyleugenol content in tarragon extracts and the ethanol versus aqueous extracts from two Artemisia dracunculus cultivars (French and Russian tarragon) were tested for blood glucose lowering effects in rats. It could be demonstrated that aqueous extracts of both Artemisia cultivars did not contain detectable amounts of estragole and methyleugenol, whereas ethanol extracts (60% v/v) of the French cultivar contained higher levels of the aforementioned compounds than those of the Russian cultivar. Further testing revealed that Russian tarragon lowered blood glucose levels in rats after glucose challenge, with the ethanol extract being as active as the aqueous extract. The results suggest that by using adequate production procedures the amount of potentially harmful compounds in extracts can be limited without affecting the overall pharmacological activities of these preparations.

Artemisia dracunculus L. (tarragon): a critical review of its traditional use, chemical composition, pharmacology, and safety.

Artemisia dracunculus L. (tarragon) has a long history of use as a spice and remedy. Two well-described "cultivars" (Russian and French) are used widely and differ in ploidy level, morphology, and chemistry. Key biologically active secondary metabolites are essential oils (0.15-3.1%), coumarins (>1%), flavonoids, and phenolcarbonic acids. In vivo studies mainly in rodents, particularly from Russian sources, highlight potential anti-inflammatory, hepatoprotective, and antihyperglycemic effects. Despite concerns about the toxic effects of two of its main constituents, estragole (up to 82%) and methyleugenol (up to 39%), no acute toxicity or mutagenic activity has been reported at doses relevant for human consumption. Water extracts of A. dracunculus contain very low amounts of estragole and methyleugenol and, therefore, are considered to pose a very limited risk. Overall, a stronger focus on clinical studies and precise taxonomic and phytochemical definition of the source material will be essential for future research efforts.

Comparative evaluation of two different Opuntia ficus-indica extracts for blood sugar lowering effects in rats.

Stems of Opuntia ficus-indica (L.) Mill. (OFI) are traditionally used in Mexico to treat diabetes mellitus. Less research data are available for combinations of stem and fruit preparations. The present study was designed to investigate the effects of an aqueous extract prepared from the cladodes and a proprietary stem/fruit skin-blend (stem/fruit skin ratio 75/25) of OFI on blood glucose and plasma insulin in normal rats. A dose finding study with the traditional cladode OFI extract revealed that maximum effects on blood glucose and insulin were observed after oral administration in a dose range of 6-176 mg/kg. The proprietary OFI blend significantly lowered blood glucose levels in the glucose tolerance test to a similar extent (p < 0.05 vs control) as the traditional aqueous cladode extract when administered in a dose of 6 mg/kg. In contrast to the aqueous extract, the proprietary blend significantly increased basal plasma insulin levels (p < 0.01 vs control) indicating a direct action on pancreatic beta cells. The results suggest that both OFI extracts exert hypoglycemic activities in rats in doses as low as 6 mg/kg but that the effects of the proprietary stem/fruit blend were more pronounced in our model.

Acute blood glucose lowering effects and long-term safety of OpunDia supplementation in pre-diabetic males and females.

AIM OF THE STUDY: The aim of this study was to evaluate the acute and chronic effects of OpunDia (Opuntia ficus-indica) in obese pre-diabetic men and women. MATERIALS AND METHODS: This double-blind placebo controlled study included participants (age range of 20-50 years) randomly assigned to one of the two groups and given a 16-week supply of either the 200 mg OpunDia (n=15), or placebo (n=14). The acute phase of the study consisted of an oral glucose tolerance test (OGTT) with a 400 mg bolus of OpunDia given 30 min before orally ingesting a 75 g glucose drink. Baseline and post 16-week concentrations of glucose, insulin, hsCRP, adiponectin, proinsulin, Hb1Ac, cholesterol, and a comprehensive metabolic panel were collected along with body composition measured via densitometry (BOD POD). A repeated measures ANOVA was conducted to determine any significant interactions between group and time. Follow-up analysis was performed to determine differences among groups at each time point. Paired t-tests were performed on all variables to determine if any within group differences existed across time. RESULTS: There was a statistically significant decrease (P<0.05) in the blood glucose concentrations at the 60 (205.92+/-36.90 and 188.84+/-38.43 mg/dL, respectively), 90 (184.55+/-33.67 and 169.74+/-35.16 mg/dL, respectively) and 120 min (159.24+/-17.85 and 148.89+/-24.86 mg/dL, respectively) time points with the pre-OGTT compared to the OpunDia bolus trial. There were no between-group differences found with the OGTT time points, area under the curve, blood chemistry variables (insulin, hsCRP, adiponectin, proinsulin, Hb1Ac), diet analysis variables (carbohydrates, fat, protein and total kcals), body composition variables (fat mass, fat free mass, percent body fat and total body weight), or blood chemistry safety parameters (comprehensive metabolic panel) pre-to-post 16-week intervention. CONCLUSIONS: This study shows the acute blood glucose lowering effects and the long-term safety of the proprietary product OpunDia, thus supporting the traditional use of Opuntia ficus-indica for blood glucose management.

Garcinia mangostana L.: a phytochemical and pharmacological review.

Garcinia mangostana L. (mangosteen, Clusiaceae) has a long history of use as a medical plant, mostly in Southeast Asia. This is a review of the phytochemistry and pharmacology of mangosteen. Traditionally mangosteen is famous for its antiinflammatory properties and is used in the treatment of skin infections and wounds. Other applications include the therapy of various conditions such as dysentery, different urinary disorders, cystitis and gonorrhoea. This review highlights the development of this botanical drug into a widely used nutraceutical. Products derived from G. mangostana are now distributed increasingly all over the world. This has given rise to a concomitant increase in research on the phytochemical constituents and biological activity of mangosteen. Central to the biological activity of the species are xanthones which are reviewed in detail. A comprehensive assessment of the biological activities of individual xanthones as well as extracts of G. mangostana is included. In addition, its potential in terms of developing novel drug leads is assessed. Products containing its fruits are now sold widely as 'liquid botanical supplements', but evidence for the health benefits of these products is still lacking. As shown here, a serious weakness in our knowledge is the lack of clinical data and it is not yet clear to what extent the findings about pharmacological activities are of potential clinical relevance.