Metabolic and Performance Effects of Yerba Mate on Well-trained Cyclists.

INTRODUCTION: Yerba Mate (YM) is a South American plant, rich in polyphenols, saponins, and xanthines, of growing scientific interest because of its metabolic effects. YM has been shown to increase fat utilization during exercise in untrained humans, but its effects on well-trained individuals during exercise are unknown. METHODS: We characterized metabolic and physical performance effects of YM in 11 well-trained male cyclists. In a double-blind crossover design, participants ingested 5 g of YM or placebo (PL; maltodextrin) daily for 5 d and 1 h before experimental trials. RESULTS: Ergometer-based tests included a submaximal step test (SST) at 30%-80% of V˙O2max (6 × 5-min stages), followed by a cycloergometer-based time trial (TT) test to complete mechanical work (~30 min; n = 9). Before and during tests, blood and respiratory gas samples were collected. YM increased resting plasma adrenaline concentration (P = 0.002), and fat utilization by 23% at 30%-50% V˙O2max versus PL (Glass effect sizes (ES) ± 95% confidence interval (CI), 0.8 ± 0.55) correlating strongly with post-SST plasma (glycerol; r = 0.758). Treatment effects on rates of perceived exertion, heart rate, and gross efficiency were unclear during SST. Respiratory exchange ratio during TT indicated carbohydrate dependence and did not differ between treatments (PL, 0.95 ± 0.03 (SD); YM, 0.95 ± 0.02). TT performance showed a small (ES = 0.38 ± 0.33) but significant (P = 0.0278) improvement with YM (PL, 30.1 ± 1.8 min (SD); YM, 29.4 ± 1.4 min; 2.2% ± 2% (95% CI)), with an average increase of 7-W power output (ES = 0.2 ± 0.19; P = 0.0418; 2.3% ± 2% (95% CI)) and 2.8% V˙O2 (P = 0.019). Pacing displayed lower power output after 30% of total TT workload in PL vs YM. CONCLUSIONS: YM increased fat utilization during submaximal exercise and improved TT performance, but performance-enhancement effect was unrelated to measures of substrate metabolism during maximal exercise.

Purification and Partial Structural Characterization of a Complement Fixating Polysaccharide from Rhizomes of Ligusticum chuanxiong.

Rhizome of Ligusticum chuanxiong is an effective medical plant, which has been extensively applied for centuries in migraine and cardiovascular diseases treatment in China. Polysaccharides from this plant have been shown to have interesting bioactivities, but previous studies have only been performed on the neutral polysaccharides. In this study, LCP-I-I, a pectic polysaccharide fraction, was obtained from the 100 °C water extracts of L. chuangxiong rhizomes and purified by diethylaminethyl (DEAE) sepharose anion exchange chromatography and gel filtration. Monosaccharide analysis and linkage determination in addition to Fourier transform infrared (FT-IR) spectrometer and Nuclear magnetic resonance (NMR) spectrum, indicated that LCP-I-I is a typical pectic polysaccharide, with homo-galacturonan and rhamnogalacturonan type I regions and arabinogalactan type I and type II (AG-I/AG-II) side chains. LCP-I-I exhibited potent complement fixation activity, ICH50 of 26.3 ± 2.2 µg/mL, and thus has potential as a natural immunomodulator.

Natural products from Zanthoxylum heitzii with potent activity against the malaria parasite.

BACKGROUND: Zanthoxylum heitzii (Rutaceae) (olon) is used in traditional medicine in Central and West Africa to treat malaria. To identify novel compounds with anti-parasitic activity and validate medicinal usage, extracts and compounds isolated from this tree were tested against the erythrocytic stages of the human malaria parasite Plasmodium falciparum and for inhibition of transmission in rodent malaria parasite Plasmodium berghei. RESULTS: Hexane bark extract showed activity against P. falciparum (IC50 0.050 µg/ml), while leaf and seed extracts were inactive. Fractionation of the hexane bark extract led to the identification of three active constituents; dihydronitidine, pellitorine and heitziquinone. Dihydronitidine was the most active compound with an IC50 value of 0.0089 µg/ml (25 nM). This compound was slow acting, requiring 50 % longer exposure time than standard anti-malarials to reach full efficacy. Heitziquinone and pellitorine were less potent, with IC50 values of 3.55 µg/ml and 1.96 µg/ml, but were fast-acting. Plasmodium berghei ookinete conversion was also inhibited by the hexane extract (IC50 1.75 µg/ml), dihydronitidine (0.59 µg/ml) and heitziquinone (6.2 µg/ml). Water extracts of Z. heitzii bark contain only low levels of dihydronitidine and show modest anti-parasitic activity. CONCLUSIONS: Three compounds with anti-parasitic activity were identified in Z. heitzii bark extract. The alkaloid dihydronitidine is the most effective of these, accounting for the bulk of activity in both erythrocytic and transmission-blocking assays. These compounds may present good leads for development of novel anti-malarials and add to the understanding of the chemical basis of the anti-parasitic activity in these classes of natural product.

Antiplasmodial, anti-complement and anti-inflammatory in vitro effects of Biophytum umbraculum Welw. traditionally used against cerebral malaria in Mali.

ETHNOPHARMACOLOGICAL RELEVANCE: Biophytum umbraculum Welw. (Oxalidaceae) is a highly valued African medicinal plant used for treatment of cerebral malaria, a critical complication of falciparum malaria. AIM OF THE STUDY: To provide additional information about traditional use of B. umbraculum and to test plant extracts and isolated compounds for in vitro activities related to cerebral malaria. MATERIALS AND METHODS: The traditional practitioners were questioned about indication, mode of processing/application, dosage and local name of B. umbraculum. Organic extracts and some main constituents of the plant were investigated for anti-malaria, anti-complement activity and inhibition of NO secretion in a RAW 264.7 cell line. RESULTS: Treatment of cerebral malaria was the main use of B. umbraculum (fidelity level 56%). The ethyl acetate extract showed anti-complement activity (ICH50 5.7±1.6µg/ml), inhibition of macrophage activation (IC50 16.4±1.3µg/ml) and in vitro antiplasmodial activity (IC50 K1 5.6±0.13µg/ml, IC50 NF54 6.7±0.03µg/ml). The main constituents (flavone C-glycosides) did not contribute to the activity of the extract. CONCLUSION: Inhibition of complement activation and anti-inflammatory activity of B. umbraculum observed in this study might be possible targets for adjunctive therapy in cerebral malaria together with its antiplasmodial activity. However, clinical trials are necessary to evaluate the activity due to the complex pathogenesis of cerebral malaria.

Chemical characterization and complement fixation of pectins from Cola cordifolia leaves.

Defatted leaves from the medicinal tree Cola cordifolia were extracted with 50% EtOH, 50 °C and 100 °C water. The polysaccharide rich extracts were fractionated and the structure of the polysaccharides elucidated. Linkage analysis of the polysaccharides indicates a rhamnogalacturonan type I backbone where both Rha and parts of GalA are substituted in position 3, indicating a highly branched polymer with short side chains. The purified fractions were tested for complement fixation, macrophage stimulating activity and anti-adhesion activity towards Helicobacter pylori. Here we report on complex and polydisperse types of pectins (Mw: 3-1300 kDa) as well as the presence of low Mw (<3 kDa) acidic oligosaccharides. The fractions showed a moderate complement fixing activity and no macrophage activating effects after LPS removal. Anti-adhesion activity towards H. pylori was not found.

Inulin-rich fractions from Vernonia kotschyana roots have anti-ulcer activity.

ETHNOPHARMACOLOGICAL RELEVANCE: Roots from Vernonia kotschyana are on the national list of essential drugs in Mali (West-Africa). It is sold under the name Gastrosedal and it used against ailments like gastritis and gastric ulcer. To evaluate the anti-ulcer, immunomodulating activities and toxicity of 50 and 100 °C water extracts, Vk50-I and Vk100-I respectively, from the roots of Vernonia kotschyana. MATERIALS AND METHODS: Characterization of extracts was carried out by GC, colorimetric and biological methods. Vk50-I and Vk100-I were administrated 50 min before induction of gastric ulcers in mice with 0.3 M HCl-60% EtOH. Inhibition of ulcer formation was calculated based on lesion index. Immunological activities were measured by complement fixation and macrophage activation. Toxicity assay was carried out on brine shrimps. RESULTS: Vk50-I (98% inulin) and Vk100-I (83% inulin) from Vernonia kotschyana significantly inhibited the formation of gastric lesions in mice (100 mg/kg). No immunomodulating activities or toxicity were found. CONCLUSIONS: Our results show that inulin is probably partly responsible for the anti-ulcer activity of Gastrosedal. In addition, it is possible that water soluble polysaccharides (mainly inulin) have an indirect impact on the general health of the GI.

Anti-ulcer polysaccharides from Cola cordifolia bark and leaves.

ETHNOPHARMACOLOGICAL RELEVANCE: Aqueous extracts of bark and leaves of C. cordifolia are traditionally used in Mali (West Africa) in the treatment of wounds and gastric ailments like abdominal pain, gastritis and gastric ulcers. AIM OF THE STUDY: To evaluate and compare the anti-ulcer and immunological activities, as well as the toxicity of polysaccharide rich water extracts from the bark and leaves of C. cordifolia. MATERIALS AND METHODS: Gastric ulcers were induced in rats and the inhibition of ulcer formation was calculated based on lesion index. Immunological activities were measured by complement fixation and macrophage activation. Toxicity was tested on brine shrimps. The two extracts were characterised by GC, Yariv-precipitation and quantification of phenolic compounds. An ethnomedical survey on C. cordifolia was carried out in Siby (Mali, West-Africa) to generate more knowledge about the traditional use. RESULTS: Bark and leaf extracts from C. cordifolia significantly inhibited the formation of gastric lesions in rodents in a dose depending manner. CCbark50 showed a high complement fixation activity in vitro. No toxicity was found. The ethnomedical survey showed that C. cordifolia was mainly used for treating pain and wounds. CONCLUSIONS: Our results shows that the bark and the leaves comprise a dose dependant anti-ulcer activity in an experimental rat model (no statistical difference between the plant parts). Clinical studies should be performed to evaluate the effect of both bark and leaves of C. cordifolia as a remedy against gastric ulcer in human.

Chemical and biological characterization of pectin-like polysaccharides from the bark of the Malian medicinal tree Cola cordifolia.

The bark of Cola cordifolia used in Malian traditional medicine contains unusual types of polysaccharides with immunomodulating activities. We report for the first time on the structure of a polymer designated CC1P1 having the repeating structure [2→)[α-D-Gal(1→3)]α-L-Rha(1→4)α-d-GalA(1→] as determined by NMR and GC/MS. α-Linked Gal is unusual in pectins. The Mw of 135 kDa was determined by SEC-MALLS. CC1P2 (1400 kDa), another polymer, having the same backbone, but this was substituted with α-4-OMe-GlcA, α-2-OMe-Gal and α-Gal as terminal units. CC1P1 shows a high complement-fixing activity, IC50 being 2.2 times lower than the positive pectin control PMII (IC50 appr. 71 µg/mL) while IC50 of CC1P2 is 1.8 times lower. The simple structure of CC1P1 did not activate macrophages, while CC1P2 (100 µg/mL) showed the same potency as the positive controls PMII (100 µg/mL) and LPS (500 ng/mL). No cytotoxicity was detected.

Ethnopharmacological uses of Erythrina senegalensis: a comparison of three areas in Mali, and a link between traditional knowledge and modern biological science.

This paper describes ethnopharmacological knowledge on the uses of Erythrina senegalensis DC (Fabaceae) in traditional medicine in three different areas (Dioila, Kolokani and Koutiala) in Mali. Data were collected using interviews of traditional healers selected randomly. The main reported diseases for which E. senegalensis was used by the traditional healers were amenorrhea, malaria, jaundice, infections, abortion, wound, and body pain (chest pain, back pain, abdominal pain etc). The fidelity level (which estimates the agreement of traditional healers on the same area about a reported use of the plant) was calculated to compare the results from the three areas. Certain differences were noticed, the most striking was the fact that amenorrhea was the most reported disease in Dioila and Kolokani with 21% of agreement for both areas, while this use was not reported in Koutiala at all. Similarities existed between the three areas on the use of the plant against malaria and infections, although with different degree of agreement among the healers. We also report the results of a literature survey on compounds isolated from the plant and their biological activities. A comparison of these results with the ethnopharmacological information from Mali and other countries showed that some of the traditional indications in Mali are scientifically supported by the literature. For instance, the use of E. senegalensis against infectious diseases (bilharzias, schistosomiasis, pneumonia etc.) is sustained by several antibacterial and antifungal compounds isolated from different parts of the plant. The comparison also showed that pharmacologists have not fully investigated all the possible bioactivities that healers ascribe to this plant.