[Effectiveness of phytotherapy in supportive treatment of type 2 diabetes mellitus Billberry (Vaccinium myrtillus)]. / Úcinnost fytoterapie v podpurné lécbe diabetes mellitus typu 2 Boruvka cerná (Vaccinium myrtillus).

The billberry is well-known for its tasty blue-dyeing fruits. Historically the leaves and fruits were used to treat diabetes, cardiovascular diseases, dementia and cancer. Antidiabetic properties of the plant are attributed mostly to the content of anthocyanins and polyphenols. These compounds have proven their antidiabetic potential in various studies. Their mechanism of action is an increase in insulin secretion (anthocyanin pelargonidin), reduction of insulin resistance (anthocyanin cyanidin-3-glucoside), glucose resorption from the GIT (polyphenols) and enhancement of beta-cells regeneration. Besides these effects, anthocyanins contribute to the improvement of the lipid spectrum and have antioxidant, anti-inflammatory and cardioprotective activities. Antidiabetic effects of anthocyanin cyanidin-3-galactoside were compared to acarbose (synergistic effect), hypocholesterolemic activity of cyanidin-3-O-glucoside to atorvastatin (synergistic effect) and hypolipidemic properties of blueberry leaf extract to ciprofibrate (extract has a lower effect). However, in many preclinical and clinical studies different species of the Vaccinium genus and other plants with asimilar effect as the billberry were also assessed. Therefore, in order to convincingly assess the efficacy and safety of blueberry herbal medicines more studies are necessary. Such studies should shed light into the variety of anthocyanins, their particular effects and optimal doses and compare their effects with intake of foods generally rich in anthocyanins.Key words: billberry Vaccinium myrtillus diabetes mellitus phytotherapy antocyanines.

[Effectiveness of phytotherapy in supportive treatment of type 2 diabetes mellitus III. Momordica (Momordica charantia)]. / Úcinnost fytoterapie v podpurné lécbe diabetes mellitus typu 2 III. Momordika (Momordica charantia).

Momordica charantia is a thermophilic voluble plant from the tropical and subtropical regions of Asia, Africa and the Caribbean. In central Europe, momordica requires greenhouse plantations. Mature fruits resemble a cucumber or a pumpkin and can be used as other similar vegetables. Crude fruits are very bitter and refreshing. For centuries the plant has been known in Chinese traditional medicine for its antidiabetic effects as well as for the treatment of cancer or infections caused by worms, viruses and malaria. Antidiabetic effects are attributed namely to cucurbitane type triterpenoids, charantin, p-insulin and 9cis-11trans-13trans-conjugated linolenic acid. These substances in momordica preparations show antidiabetic effectiveness in clinical studies by increasing insulin secretion and deceasing insulin resistance or glucose absorption from the gut. Beside this main effect the extract possesses certain neuroprotective and antioxidant effects (especially p9cis-11trans-13trans-conjugated linolenic acid) and contributes to normalize blood lipid and adipokine levels which results in the normalization of metabolic syndrome. Antidiabetic effectiveness of momordica was compared to active treatment with several oral antidiabetic drugs and proved comparable effects. However, the number of studies is limited and their methodological approach variable. Therefore, the evidence is so far inconclusive.

[Effectiveness of phytotherapy in supportive treatment of type 2 diabetes mellitus II. Fenugreek (Trigonella foenum-graecum)]. / Úcinnost fytoterapie v podpurné lécbe diabetes mellitus typu 2 II. Pískavice recké seno (Trigonella foenum-graecum).

Fenugreek seeds are known for their characteristic smell of soup seasoning and as an ingredient of Indian curry. Traditionally the seeds are used as macerate for the treatment of diabetes, cough, and flatulence, to increase breast milk secretion, and for anti-inflammatory and aphrodisiac effects. The use is limited by its unpleasant smell and bitter taste which can be modified by adding mint leaves to the macerate. Antidiabetic properties are attributed mainly to galactomannan, 4-hydroxyisoleucin (4-OH-Ile), diosgenin and trigonelline. These substances demonstrate direct antidiabetic properties in clinical studies by increasing insulin secretion (4-OH-Ile), decreasing insulin resistance and glucose resorption from the GIT (galactomannan) and improvement in B-cells regeneration (trigonelline). Besides this main effect, the herb improves blood lipid spectre (4-OH-Ile, diosgenin), and has reno-protective (4-OH-Ile, trigonelline), neuroprotective (trigonelline) and antioxidant (diosgenin, trigonelline) effects. Antidiabetic efficacy of trigonelline is comparable to glibenclamide treatment and more effective than sitagliptine therapy. Given the large body of evidence and promising results in comparison with standard pharmacotherapy, fenugreek active substances have a potential to become a source of new antidiabetic medication.Key words: fenugreek Trigonella foenum-graecum diabetes mellitus type 2 biological activity.