24 research outputs found
Ginseng and ginkgo biloba effects on cognition as modulated by cardiovascular reactivity: a randomised trial
Background
There is some evidence to suggest that ginseng and Ginkgo biloba can improve cognitive performance, however, very little is known about the mechanisms associated with such improvement. Here, we tested whether cardiovascular reactivity to a task is associated with cognitive improvement.
Methodology/Principal findings
Using a double-blind, placebo controlled, crossover design, participants (N = 24) received two doses of Panax Ginseng (500, 1000 mg) or Ginkgo Biloba (120, 240 mg) (N = 24), and underwent a series of cognitive tests while systolic, diastolic, and heart rate readings were taken. Ginkgo Biloba improved aspects of executive functioning (Stroop and Berg tasks) in females but not in males. Ginseng had no effect on cognition. Ginkgo biloba in females reversed the initial (i.e. placebo) increase in cardiovascular reactivity (systolic and diastolic readings increased compared to baseline) to cognitive tasks. This effect (reversal) was most notable after those tasks (Stroop and Iowa) that elicited the greatest cardiovascular reactivity during placebo. In males, although ginkgo also decreased cardiovascular readings, it did so from an initial (placebo) blunted response (i.e. decrease or no change from baseline) to cognitive tasks. Ginseng, on the contrary, increased cardiovascular readings compared to placebo.
Conclusions/Significance
These results suggest that cardiovascular reactivity may be a mechanism by which ginkgo but not ginseng, in females is associated with certain forms of cognitive improvement
A systematic review, meta-analysis, and meta-regression of the impact of diurnal intermittent fasting during Ramadan on body weight in healthy subjects aged 16 years and above
PURPOSE: Studies on the effect of Ramadan diurnal intermittent fasting (RDIF) on body weight have yielded conflicting results. Therefore, we conducted a systematic review and meta-analysis to estimate the effect size of body weight changes in healthy, non-athletic Muslims practicing Ramadan fasting, and to assess the effect of covariates such as age, sex, fasting time duration, season, and country, using subgroup analysis, and meta-regression. Covariate adjustments were performed to explain the variability of weight change in response to Ramadan fasting.METHODS: CINAHL, Cochrane, EBSCOhost, EMBASE, Google Scholar, ProQuest Medical, PubMed/MEDLINE, ScienceDirect, Scopus, and Web of Science databases were searched from date of inception in 1950 to the end of August 2019.RESULTS: Eighty-five studies, conducted in 25 countries during 1982-2019, were identified. RDIF yielded a significant, but small reduction in body weight (K = 85, number of subjects, N = 4176 (aged 16-80 years), Hedges' g =- 0.360, 95% confidence interval (CI) - 0.405 to - 0.315, I2 = 45.6%), this effect size translates into difference in means of - 1.022 kg (95% CI - 1.164 kg to - 0.880 kg). Regression analysis for moderator covariates revealed that fasting time (min/day) is a significant (P < 0.05) moderator for weight change at the end of Ramadan, while age and sex are not. Variable effects for the season and country were found.CONCLUSION: RDIF may confer a significant small reduction in body weight in non-athletic healthy people aged 16 years and above, directly associated with fasting time and variably correlated with the season, and country.</p
Passiflora incarnata attenuation of neuropathic allodynia and vulvodynia apropos GABA-ergic and opioidergic antinociceptive and behavioural mechanisms
Background: Passiflora incarnata is widely used as an anxiolytic and sedative due to its putative GABAergic
properties. Passiflora incarnata L. methanolic extract (PI-ME) was evaluated in an animal model of streptozotocininduced
diabetic neuropathic allodynia and vulvodynia in rats along with antinociceptive, anxiolytic and sedative
activities in mice in order to examine possible underlying mechanisms.
Methods: PI-ME was tested preliminary for qualitative phytochemical analysis and then quantitatively by proximate
and GC-MS analysis. The antinociceptive property was evaluated using the abdominal constriction assay and hot
plate test. The anxiolytic activity was performed in a stair case model and sedative activity in an open field test. The
antagonistic activities were evaluated using naloxone and/or pentylenetetrazole (PTZ). PI-ME was evaluated for
prospective anti-allodynic and anti-vulvodynic properties in a rat model of streptozotocin induced neuropathic pain
using the static and dynamic testing paradigms of mechanical allodynia and vulvodynia.
Results: GC-MS analysis revealed that PI-ME contained predominant quantities of oleamide (9-octadecenamide),
palmitic acid (hexadecanoic acid) and 3-hydroxy-dodecanoic acid, among other active constituents. In the
abdominal constriction assay and hot plate test, PI-ME produced dose dependant, naloxone and pentylenetetrazole
reversible antinociception suggesting an involvement of opioidergic and GABAergic mechanisms. In the stair case
test, PI-ME at 200 mg/kg increased the number of steps climbed while at 600 mg/kg a significant decrease was
observed. The rearing incidence was diminished by PI-ME at all tested doses and in the open field test, PI-ME
decreased locomotor activity to an extent that was analagous to diazepam. The effects of PI-ME were antagonized
by PTZ in both the staircase and open field tests implicating GABAergic mechanisms in its anxiolytic and sedative
activities. In the streptozotocin-induced neuropathic nociceptive model, PI-ME (200 and 300 mg/kg) exhibited static
and dynamic anti-allodynic effects exemplified by an increase in paw withdrawal threshold and paw withdrawal
latency. PI-ME relieved only the dynamic component of vulvodynia by increasing flinching response latency.
Conclusions: These findings suggest that Passiflora incarnata might be useful for treating neuropathic pain. The
antinociceptive and behavioural findings inferring that its activity may stem from underlying opioidergic and
GABAergic mechanisms though a potential oleamide-sourced cannabimimetic involvement is also discussed
Mycorrhizal synthesis between Pisolithus arhizus and adult clones of Arbutus unedo in vitro and in nursery
Arbutoid mycorrhizae were synthesized between adult selected
clones of Arbutus unedo L. and Pisolithus arhizus. Two micropropagated
clones were tested: AL1, in vitro and C1 (acclimatized plants)
in nursery and later in a field trial. In vitro, rooted shoots were transferred
to test tubes containing the substrate previously inoculated with
mycelium cultured on agar. In the nursery, two inoculation treatments
were tested (vegetative inocula or dry sporocarps) and compared to control
plants. In the field trial, plants from nursery inoculation treatments
were compared and an additional control treatment using seedlings was
implemented. Plant height was evaluated 4 months later in the nursery
and 20 months later in the field trial. Roots were examined by morphological
and histological studies: a) in vitro plantlets one month after
inoculation and nine months after acclimatization; and b) 20 months after
the field trial was established. Arbutoid mycorrhizae were observed in
vitro one month after inoculation, indicating compatibility between A.
unedo and P. arhizus. These showed the presence of a mantle, Hartig net,
and intracellular hyphal complexes confined to the epidermal root cells.
Arbutoid mycorrhizae were also observed nine months after acclimatiza-
Fund project: This work was supported by a PhD fellowship
(SFRH/BD/37170/2007) from the Portuguese Foundation for Science
and Technology (FCT)
The online version is available at http://link.springer.com
Filomena Gomes ( ) • Esteban San Martin
Filomena Gomes. CERNAS, Dep. Recursos Florestais, Escola Superior
Agrária Coimbra, Bencanta, 3040-316, Coimbra, Portugal, Tel: 351 239
802940, Fax: 351 239 802979, Email: [email protected]
Helena Machado
INIAV, Instituto Nacional de Investigação Agrária e Veterinária, IP.,
Av. República, Quinta do Marquês 2780-159 Oeiras, Portugal
A. Portugal • Jorge M. Canhoto
Centre of Functional Ecology, Department of Life Sciences, University
of Coimbra, Ap. 3046, 3001-401 Coimbra, Portugal.
Corresponding editor: Chai Ruihai
tion in inoculated and control plants. In order to confirm the identity of
mycorrhizae, molecular techniques were used, in previously inoculated in
vitro plants, 12 months after acclimatization. Thelephora and Hebeloma
mycorrhizae, two types of highly competitive and widespread mycorrhizae
on nurseries were identified. In the nursery, dry sporocarp
treatment improved plant height after four months. In a field trial (20
months later), plants growth did not show significant differences. By this
time, mycorrhized roots with Cenococcum geophilum and other types
were identified. These results and their implications on A. unedo breeding
program are discussed.F. Gomes was supported by a PhD fellowship
(SFRH/BD/37170/2007) from the Portuguese Foundation for
Science and Technology (FCT)
