Herbs in exercise and sports

ABSTRACT: The use of herbs as ergogenic aids in exercise and sport is not novel. Ginseng, caffeine, ma huang (also called 'Chinese ephedra'), ephedrine and a combination of both caffeine and ephedrine are the most popular herbs used in exercise and sports. It is believed that these herbs have an ergogenic effect and thus help to improve physical performance. Numerous studies have been conducted to investigate the effects of these herbs on exercise performance. Recently, researchers have also investigated the effects of Eurycoma longifolia Jack on endurance cycling and running performance. These investigators have reported no significant improvement in either cycling or running endurance after supplementation with this herb. As the number of studies in this area is still small, more studies should be conducted to evaluate and substantiate the effects of this herb on sports and exercise performance. For instance, future research on any herbs should take the following factors into consideration: dosage, supplementation period and a larger sample size.     

Florivores decrease pollinator visitation in a self-incompatible plant

Different biotic interactions may influence one another to produce complex patterns of direct and indirect effects, which together influence plant reproductive success. However, so far most studies on plant-animal interactions have focused on single interactions in isolation. In this study, we studied the effect of florivory by the weevil Cionus nigritarsis on pollinator visitation rate in the self-incompatible perennial herb Verbascum nigrum by combining observations of florivory and pollination in natural populations with records of pollinator visitation to plants with different levels of experimentally inflicted damage.Increasing levels of damage through either natural or simulated florivory resulted in fewer pollinator visits per plant and per flower. As expected, the magnitude of the indirect effect of florivory on pollinator visitation was proportional to the intensity of florivory. Our results indicate that biotic non-pollinating agents, such as florivores, may induce substantial changes in pollinator availability. Therefore, studies addressing different plant-animal interactions in parallel are necessary to better comprehend the factors influencing the reproductive performance and demography of flowering plants.     

A comprehensive review on the stinging nettle effect and efficacy profiles. Part II: Urticae radix

Nettle root is recommended for complaints associated with benign prostatic hyperplasia (BPH). We therefore conducted a comprehensive review of the literature to summarise the pharmacological and clinical effects of this plant material. Only a few components of the active principle have been identified and the mechanism of action is still unclear. It seems likely that sex hormone binding globulin (SHBG), aromatase, epidermal growth factor and prostate steroid membrane receptors are involved in the anti-prostatic effect, but less likely that 5alpha-reductase or androgen receptors are involved. Extract and a polysaccharide fraction were shown to exert anti-inflammatory activity. A proprietary methanolic nettle root extract and particular fractions inhibited cell proliferation. Isolated lectins (UDA) were shown to be promising immunomodulatory agents, having also anti-viral and fungistatic effects. However, despite these in vitro studies it is unclear whether the in-vitro or animal data are a surrogate for clinical effects. The clinical evidence of effectiveness for nettle root in the treatment of BPH is based on many open studies. A small number of randomised controlled studies indicate that a proprietary methanolic extract is effective in improving BPH complaints. However, the significance and magnitude of the effect remains to be established in further confirmatory studies before nettle root treatment may be accepted in the guidelines for BPH treatment. The risk for adverse events during nettle root treatment is very low, as is its toxicity. Pre-clinical safety data remain to be completed.     

Issues Concerning the Eradication or Establishment and Biological Control of the Mediterranean Fruit Fly,Ceratitis capitata(Wiedemann) (Diptera: Tephritidae), in California

Classical biological control is suggested as a tool worth developing now for possible future use in the integrated pest management of the Mediterranean fruit fly (Medfly),Ceratitis capitata(Wiedemann), in California. Three factors that impact broadly on developing and implementing such a biological control program are: (1) the question of Medfly establishment, (2) quarantine considerations, and (3) agricultural and urban concerns. Each of these factors and their combined effects must be considered when discussing biological control of Medfly in California as shaped by historical perspectives on Medfly invasions, methods of Medfly eradication, and past biological control efforts against Medfly. We believe that biological control research should play a foundational role in any future Medfly management programs in California. Development of biological control should involve life history studies of Medfly and its natural enemies in their area of endemicity in sub-Saharan, southeast Africa. Medfly has been studied and should continue to be studied in areas it has invaded, because information derived from such studies provides insights into the potential distribution, abundance, and impact of Medfly populations in California. A plan for a biological research program on Medfly and its relatives and a biological control strategy are presented.     

In vitro plantlet production system for Kaempferia galanga,a rare Indian medicinal herb

A rapid clonal propagation system for Kaempferia galanga (Zingiberaceae), a rare folk medicinal herb has been developed. Various concentrations of 6-benzyladenine (BA) and a range of auxins have been investigated for in vitro plantlet production, using rhizomes as explants. In vitro plantlet production has been achieved on 0.75 × Murashige and Skoog (MS) medium supplemented with 12 μM BA, 3 μM ∝-naphthaleneacetic acid (NAA) and 3% sucrose. The procedure ensures 13-fold rate of plantlet production every 4 weeks. Hardened plantlets produced normal storage roots as the parent plants. Around 1,000 plantlets have been produced successfully for field transfer. This revised version was published online in August 2006 with corrections to the Cover Date.     

Alpha-glucosidase inhibition from a Chinese medical herb (Ramulus mori) in normal and diabetic rats and mice

Alpha-glucosidase inhibitors are oral antidiabetic drugs. A traditional Chinese medical herb, Sangzhi (Ramulus mori), appears to have properties similar to those of alpha-glucosidase inhibitors. The effects of an aqueous extract of Shangzhi (SZ) were studied in normal and alloxan diabetic rats and mice, and these results compared with those for acarbose, an alpha-glucosidase inhibitor. In our grade-dose studies, SZ was found to lower and prolong the zenith of blood glucose concentration (ZBG) after sucrose or starch loading and stabilize blood glucose levels in fasting normal and alloxan diabetic mice. After 2 weeks of SZ administration with high-calorie chow or a normal diet, the fasting and non-fasting blood glucose concentrations in alloxan diabetic mice and rats were decreased. In alloxan rats, the blood fructosamine concentration was lowered. Results for acarbose and SZ were similar. These indicate that SZ has alpha-glucosidase inhibitory effects.     

Are the young more sensitive than adults to the effects of radiofrequency fields? An examination of relevant data from cellular and animal studies

It has sometimes been assumed that children are more sensitive than adults to the effects of radiofrequency (RF) fields associated with cellular wireless telephones. However, relatively few in vitro or animal models have examined this possibility.In vitro studies have used several cell types, from both humans and rodents, including primary cells, embryonic cell lines, undifferentiated cancer cell lines, and stem cells. Overall, the balance of evidence does not suggest that field-related effects occur in any cell type: gene and protein expression were not significantly changed by exposure in nine out of 15 studies; genotoxicity was evaluated in 13 papers and in most, of these studies, no damage to DNA was detected; eight studies failed to demonstrate induction of apoptosis; and three studies reported lack of oxidative stress induction by RF-exposures. Five of eight studies investigating the effects of combined exposures to RF fields and chemical or physical agents reported a lack of field-related effects.In addition, few papers have been published on the effects of low level exposure of immature animals. The available results are very limited, both in terms of signals used and biological endpoints investigated, but the evidence does not indicate that prenatal or early postnatal exposures are associated with acute adverse responses or the development of detrimental changes in the long-term. Overall, this suggests that young animals may not be significantly more sensitive than adults, but there is clearly a need for further studies to be carried out.     

Ecogeography of the grass genusHelictotrichon (Poaceae: Aveneae) in the Mediterranean and adjacent regions

The geographical distribution of the grass genusHelictotrichon in the Mediterranean Region is analysed and mapped for 33 taxa. Based on only a single life form (perennial herb), a variety of edaphically, climatically and altitudinally differently adapted species complexes has evolved in the area. Most of these complexes show west-east disjunctions and contain geographically, sometimes even edaphically vicarious taxa with complementary distribution. A transition from mesomorphic to xeromorphic habit occurred independently in different species groups and led to the establishment of the modern Mediterranean taxa which are in part highly polyploid derivatives of more mesophilic diploids. The significance of polyploidy, patterns of parapatric and sympatric distribution, biogeographical borders, and centres of species diversity are discussed in context with the history of the Mediterranean vegetation. New combinations are:Helictotrichon setaceum subsp.petzense, H. pratense subsp.lusitanicum, H. praetutianum.     

Activity of Wedelia calendulacea Less. in post-menopausal osteoporosis

Wedelia calendulacea Less., a perennial herb containing isoflavanoids, is used in liver disorders, uterine hemorrhage and menorrhagia. Osteoporosis in women occurs mainly due to estrogen deficiency following menopause. Studies indicate that isoflavones are estrogenic enough to promote bone formation. Our study was aimed to investigate the antiosteoporotic effect of the ethanol extract of W. calendulacea in the ovariectomized rat model of osteoporosis, at two different dose levels of 500 and 750 mg/kg/body wt. day. The findings, assessed on the basis of biomechanical and biochemical parameters, showed that the ethanol extract of the plant had a definite protective effect. This was further supported by the histopathological studies. Phytochemical investigation revealed the presence of isoflavones and wedelolactone, which are known to act as phytoestrogens and may be responsible for the antiosteoporotic activity.     

Bioassays of nutrient limitation in a tropical rain forest soil

Summary Six speices of shrubs and one large herb with contrasting life history patterns were used as bioassays of nutrient availability in a Costa Rican lowland rain forest soil. Growth responses of the herb (Phytolacca rivinoides, Phytolaccaceae) confirmed soil measurements indicating high availability of N and potentially limiting levels of P, K, Mg and Ca. Growth responses of the shrub species (Miconia spp., Melastomataceae and Piper spp., Piperaceae) to a complete nutrient fertilizer were generally less than that of Phytolacca. Lack of a strong shrub response to +P fertilization is probably due to mycorrhizal associations and slower growth rates of woody species. In general, increased growth did not occur at the expense of phenolic production in the leaves. The results emphasize that assessment of specific nutrient limitations to plant growth vary depending on species selected for the bioassay, even among species from the same community.     

Light, nutrients and the growth of herbaceous forest species

The herb layer of forests planted on former agricultural land often differs from that of old-growth forest. This study investigates if the expected increased nutrient availability in the shaded conditions of newly planted forests and the plasticity of the species to adjust their biomass allocation to different levels of light and nutrients help to explain these differences in the herb layers of the two forest types. In a greenhouse experiment biomass distribution and production of two species characteristic for the highly shaded forest floor, Circaea lutetiana and Mercurialis perennis, and two species more common in the forest-edge, Aegopodium podagraria and Impatiens parviflora were studied at different levels of light (2%, 8% and 66% of the full light level) and nutrients (30 and 300 kg N ha^–1 per year). The main factor affecting allocation and biomass production was light availability. Nutrient supply only had a significant effect at the higher light levels. Species were mainly plastic to changes in light and the two species from the forest floor showed to be more rigid in allocation pattern than the species from the forest-edge. So, although the species from the forest-edge were more plastic, they did not profit from the increased nutrient supply because the main factor affecting biomass distribution and production was light availability.     

The phylogenetic relationships and evolution of the Canarian laurel forest endemicIxanthus viscosus (Aiton) Griseb. (Gentianaceae): Evidence frommatK and ITS sequences, and floral morphology and anatomy

The phylogenetic relationships of the Canarian laurel forest endemicIxanthus viscosus (Aiton) Griseb. (Gentianaceae) are investigated through a cladistic analysis of sequence variation of parts of the chloroplast genematK and the ITS region of nuclear ribosomal DNA. The floral anatomical and morphological characteristics ofIxanthus based on paraffin sections and SEM studies are also discussed. In the molecular analysesIxanthus is part of a clade of mostly temperate Erythraeinae and Chironiinae sensu Gilg, in which it is sister to the mostly Mediterranean annualBlackstonia. This relationship is supported by farreaching similarities in flower morphology and anatomy, and the shared possession of at least some perfoliate leaves. This finding contradicts most former classifications in whichIxanthus was placed either in subtribe Gentianinae which never includedBlackstonia, or in a subtribe of its own which was suggested to connect woody tropical with herbaceous temperate taxa. The phylogenetic relationships found here show that 1) the sister group ofIxanthus is distributed in the Mediterranean area, and that 2) its habit as a basally woody suffrutescent herb is best interpreted as an advanced character state.     

Seasonal reversibility of acclimation to irradiance in leaves of common box (Buxus sempervirens L.) in a deciduous forest

Understorey shade plants are seasonally exposed to dramatic changes in light conditions in deciduous forests related with the dynamics of the overstorey leaf phenology. These transitions are commonly followed by changes in herb plant communities, but shade-tolerant evergreen species must be able to adapt to changing light conditions. In this work we checked the photoprotective responses of evergreen species to acclimate to the shady summer environment and reversibly de-acclimate to a more illuminated environment after leaf fall on deciduous overstoreys. For that purpose we have followed the process of light acclimation in leaves of common box (Buxus sempervirens) during the winter to spring transition, which decrease irradiance in the understorey, and conversely during the transition from summer to autumn. Four parameters indicative of the structure and degree of acclimation of the photosynthetic apparatus have been studied: chlorophyll a/b ratio which is supposed to be inversely proportional to the antenna size, α/β-carotene which increases in shade acclimated leaves and the pools of α-tocopherol and xanthophyll cycle pigments (VAZ) which are two of the main photoprotection mechanisms in plants. Among these parameters, chlorophyll a/b ratio and VAZ pool responded finely to changes in irradiance indicating that modifications in the light harvesting size and photoprotective capacity contribute to the continuous acclimation and de-acclimation of long-lived evergreen leaves.     

A simple plant polytene chromosome system,and its use for in situ hybridisation

When the cotyledons of Pisum sativum are cultured in the presence of 2–4D, large populations of cells with polytene chromosomes are stimulated to enter prophase; the use of these chromosome for studies of in situ hybridisation with nucleic acids is described.     

The role of trematode parasites in larval anuran communities: an aquatic ecologist’s guide to the major players

Conservation strategies depend on our understanding of the ecosystem and community dynamics. To date, such understanding has focused mostly on predator–prey and competitor interactions. It is increasingly clear, however, that parasite–host interactions may represent a large, and important, component of natural communities. The need to consider multiple factors and their synergistic interactions if we are to elucidate the contribution of anthropogenic factors to loss in biodiversity is exemplified by research into present-day amphibian declines. Only recently has the role of factors such as trematode parasite infections been incorporated into studies of the population and community dynamics of aquatic systems. We argue that this is due, at least in part, to difficulties faced by aquatic ecologists in sifting through the complex systematics that pervade the parasite literature. We note that two trematode species are of dominant importance with regard to North American larval anuran communities, and provide in this review a clear explanation of how to distinguish between the infective stages of these two parasites. We describe the general biology and life history of these parasites, as well as what is known about their effect on larval anurans, and the interactive effects of environmental stressors (typically anthropogenic in nature) and parasites on larval anurans. We hope that this review will convince the reader of the potential importance of these parasites to aquatic communities in general, and to amphibian communities specifically, and will also provide the information necessary for aquatic ecologists to more frequently consider the role of these parasites in their studies of aquatic ecology.     

Regional and local variation in seedling emergence,mortality and recruitment of a perennial herb in Mediterranean mountain habitats

Spatial patterns of seedling regeneration of woody Mediterranean plants are widely documented, with seedlings and juveniles growing almost exclusively under shrub and tree canopy. Neighbourhood habitat amelioration and consequent facilitative effects on recruitment have been extensively suggested as the major determinant of such spatial pattern for Mediterranean vegetation. Much less is known on recruitment patterns of perennial herbs. As herbs differ from woody plants in many relevant ecological aspects and in their life cycles, we would expect particularities in their recruitment dynamics. We analysed the spatial (regional, local and fine-scale) variation in environment (herb cover, litter depth, air temperature and irradiance) and its relationship with seedling emergence, mortality, and recruitment of the perennial herb Helleborus foetidus (Ranunculaceae) during 2 years. We conducted the study in three distant localities in south-eastern Iberian Peninsula (defining the regional scale). Local scale was defined in terms of microhabitat type based on three categories of vegetation cover (under evergreen shrubs or trees, under deciduous spiny-shrubs, and in open interspaces). Finally, fine-scale variation was defined in terms of 1 m² sampling plots. Our results showed regional, local and fine-scale variations in recruitment, with the major source of variation changing across scales. Seed input was important in determining differences in recruitment both at the largest (regional) and the finest scale. Environment had minor importance in shaping differences in recruitment at these two scales. At the local scale, variation between microhabitats was mainly related to differences in seedling survival through facilitative effects (alleviation of water and irradiance stresses) of shrub and tree cover, although such facilitative effect was not consistent in all localities or years. Our study thus points to a similarity in the spatial patterns of recruitment (and in the environmental factors shaping such patterns) between Mediterranean woody plants and perennial herbs, but much more effort is needed to assess the generality of such similarity.     

Indirect nontarget effects of host-specific biological control agents: Implications for biological control

Classical biological control of weeds currently operates under the assumption that biological control agents are safe (i.e., low risk) if they do not directly attack nontarget species. However, recent studies indicate that even highly host-specific biological control agents can impact nontarget species through indirect effects. This finding has profound implications for biological control. To better understand the causes of these interactions and their implications, we evaluate recent case studies of indirect nontarget effects of biological control agents in the context of theoretical work in community ecology. We find that although particular indirect nontarget effects are extremely difficult to predict, all indirect nontarget effects of host specific biological control agents derive from the nature and strength of the interaction between the biological control agent and the pest. Additionally, recent theoretical work suggests that the degree of impact of a biological control agent on nontarget species is proportional to the agent’s abundance, which will be highest for moderately successful control agents. Therefore, the key to safeguarding against indirect nontarget effects of host-specific biological control agents is to ensure the biological control agents are not only host specific, but also efficacious. Biological control agents that greatly reduce their target species while remaining host-specific will reduce their own populations through density-dependent feedbacks that minimize risks to nontarget species.     

Displacement of a native by an alien bumblebee: lower pollinator efficiency overcome by overwhelmingly higher visitation frequency

Biological invasions might constitute a major threat to mutualisms. Introduced pollinators might competitively displace their native counterparts, which in turn affects the pollination of native plants, if native and alien visitors differ in pollinator effectiveness. Since its invasion in 1994 into south-west Argentina, the introduced European bumblebee Bombus ruderatus has continuously increased in abundance, along with a simultaneous decrease in the abundance of the native Bombus dahlbomii. The latter is the only native bumblebee species of the temperate forests of southern South America, and the main pollinator of the endemic herb Alstroemeria aurea. In order to evaluate the impact of the ongoing displacement of the native by the alien bumblebee, we compared the pollinator effectiveness (i.e., the combination of pollinator efficiency per visit and visitation frequency) between both bumblebee species, as well as related pollinator traits that might account for potential differences in pollinator efficiency. Native Bombus dahlbomii, which has a larger body and spent more time per flower, was the more efficient pollinator compared to Bombus ruderatus, both in terms of quantity and quality of pollen deposited per visit. However, Bombus ruderatus was a much more frequent flower visitor than Bombus dahlbomii. As a consequence, Bombus ruderatus is nowadays a more effective pollinator of A. aurea than its native congener. Despite the lack of evidence of an increase in seed set at the population level, comparisons with historical records of Bombus dahlbomii abundances prior to Bombus ruderatus' invasion suggest that the overall pollination intensity of A. aurea might in fact have risen as a consequence of this invasion. Field experiments like these, that incorporate the natural variation in abundance of native and alien species, are powerful means to demonstrate that the consequences of invasions are more complex than previous manipulated and controlled experiments have suggested.     

Outdoor Studies on the Effects of Solar UV-B on bryophytes: Overview and Methodology

In this review all recent field studies on the effects of UV-B radiation on bryophytes are discussed. In most of the studies fluorescent UV-B tubes are used to expose the vegetation to enhanced levels of UV-B radiation to simulate stratospheric ozone depletion. Other studies use screens to filter the UV-B part of the solar spectrum, thereby comparing ambient levels of UV-B with reduced UV-B levels, or analyse effects of natural variations in UV-B arising from stratospheric ozone depletion. Nearly all studies show that mosses are well adapted to ambient levels of UV-B radiation since UV-B hardly affects growth parameters. In contrast with outdoor studies on higher plants, soluble UV-B absorbing compounds in bryophytes are typically not induced by enhanced levels of UV-B radiation. A few studies have demonstrated that UV-B radiation can influence plant morphology, photosynthetic capacity, photosynthetic pigments or levels of DNA damage. However, there is only a limited number of outdoor studies presented in the literature. More additional, especially long-term, experiments are needed to provide better data for statistical meta-analyses. A mini UV-B supplementation system is described, especially designed to study effects of UV-B radiation at remote field locations under harsh conditions, and which is therefore suited to perform long-term studies in the Arctic or Antarctic. The first results are presented from a long-term UV-B supplementation experiment at Signy Island in the Maritime Antarctic.