Etudes sur les boosters sexuels et la sexualité

Les boosters de NO pour maigrir sur le long terme?

14/12/2017 | Etudes Perte de poids et Etudes Anti-âge et Etudes sur les boosters sexuels et la sexualité

 

Ca fait quand même un peu beaucoup…

Sildenafil induces browning of subcutaneous white adipose tissue in overweight adults
Metabolism Volume 78, January 2018, Pages 106-117

To investigate that short-term treatment of sildenafil can induce browning of subcutaneous white adipose tissue (sWAT) in human adults.

Design
A randomized, double-blinded, placebo-controlled, parallel group trial.

Methods
Sixteen eligibility overweight male subjects were recruited, comparing 100 mg/day sildenafil versus an identical placebo therapy for 7 days. sWAT samples were collected from subjects before and after 7-day sildenafil or placebo interventions.

Results
The results showed that multilocular UCP1-positive adipocytes existed in sWAT samples from subjects after sildenafil treatment. Compared to before treatment in both group as well as after treatment in placebo, sildenafil significantly decreased adipocyte size, increased the expressions of UCP1 protein and mRNA, mitochondrial density, and leak respiratory capacity in sWAT (p < 0.05). Sildenafil also increased plasma cyclic guanosine-3′,5′-monophosphate (cGMP) and catecholamine concentrations (p < 0.05), and consequently activated the expressions of vasodilator-stimulated phosphoprotein (VASP) and p70 ribosomal S6 kinase 1 (S6 K1) (p < 0.05). Sildenafil did not activate typical brown fat.

Conclusions
The current findings demonstrate that sildenafil can induce browning of sWAT in human, and this action may be through cGMP-dependent protein kinase I and mechanistic/mammalian target of rapamycin (mTOR) signaling pathways. Sldenafil may be a promising treatment for metabolic disease.

Le Viagra est-il aussi un anti-aromatase?

01/12/2016 | Etudes Perte de poids et Etudes Anti-âge et Etudes sur les boosters sexuels et la sexualité

 

Effect of sildenafil on human aromatase activity: From in vitro structural analysis to catalysis and inhibition in cells
The Journal of Steroid Biochemistry and Molecular Biology Volume 165, Part B, January 2017, Pages 438–447       Roberta Baravalle

Highlights
• Human aromatase binds the drug sildenafil showing a Type II spectrum.
• EPR spectroscopy shows that sildenafil does not directly bind heme iron.
• Sildenafil acts as a mixed and partial inhibitor on human aromatase.
• Aromatase inhibition by sildenafil is confirmed in ST14A and MCF-7 cells.

Aromatase catalyses the conversion of androgens into estrogens and is a well-known target for breast cancer therapy. As it has been suggested that its activity is affected by inhibitors of phosphodiesterase-5, this work investigates the potential interaction of sildenafil with aromatase. This is carried out both at molecular level through structural and kinetics assays applied to the purified enzyme, and at cellular level using neuronal and breast cancer cell lines.

Sildenafil is found to bind to aromatase with a KD of 0.58 ± 0.05 μM acting as a partial and mixed inhibitor with a maximal inhibition of 35 ± 2%. Hyperfine sublevel correlation spectroscopy and docking studies show that sildenafil binds to the heme iron via its 6th axial water ligand.

These results also provide information on the starting molecular scaffold for the development of new generations of drugs designed to inhibit aromatase as well as phosphodiesterase-5, a new emerging target for breast cancer therapy.

Le curcuma est-il un inhibiteur de la 5 alpha réductase?

27/11/2016 | Etudes Compléments alimentaires et Etudes Anti-âge et Etudes sur les boosters sexuels et la sexualité

 

A new label-free screen for steroid 5α-reductase inhibitors using LC-MS
Steroids Volume 116, December 2016, Pages 67–75       Jukkarin Srivilai

Highlights
• A novel assay for 5 alpha reductase (S5αR) activity determination based on LC-MS quantitation of DHT.
• The assay showed high reproducibility and selectivity with Z′ factor of 0.77.
• The method was successfully used to quantify S5αR inhibitory activity of some herbal extracts.

Steroid 5α-reductase (S5αR) plays an important role in metabolizing testosterone into active androgen dihydrotestosterone (DHT) which is involved in many androgen dependent disorders, such as androgenic alopecia, benign prostatic hyperplasia and acne. The method for screening for S5αR inhibition is key in finding new antagonists. In this study, the label-free S5αR inhibitory assay using LC-MS was developed. S5αR type 1 enzyme was obtained from LNCaP prostate cancer cells. The enzymatic assay was optimised for enzyme-substrate (testosterone) concentration, NADPH-cofactor concentration, solvent tolerance, enzyme activity stability and incubation time. The developed assay was validated by measuring the signal to background ratio (S/B), the signal to noise ratio (S/N), the signal window (SW) and the zeta factor Z′ in accordance with published bioassay guidelines. The enzymatic reaction was performed in 96-well plates and DHT formation was determined by LC-MS. S/B, S/N, SW and Z′ factor were well above acceptable criteria and the reproducibility was good using Z′ factor other 3 days and further validated by dutasteride and finasteride inhibition. The method was successfully applied to quantify S5αR inhibitory activity of some Thai herbal extracts.

Two plant extracts, Impatiens balsamina L. and Curcuma longa L. showed IC50 at 5.4 ± 0.2 and 9.0 ± 1.2 μg mL−1 and are therefore promising sources of new S5αR inhibitors. The assay has high selectability and reproducibility and suited to medium throughput screening required by phytochemistry.

80% des suppléments européens de rhodiole sont de mauvaise qualité

27/05/2016 | Etudes Compléments alimentaires et Etudes Perte de poids et Etudes Anti-âge et Etudes sur les boosters sexuels et la sexualité

 

The authenticity and quality of Rhodiola rosea products
Phytomedicine Volume 23, Issue 7, 15 June 2016, Pages 754–762       Anthony Booker

Les suppléments européens de rhodiole sont de mauvaise qualité

Rhodiola rosea L. Crassulaceae, root (Golden Root, Arctic Root) is a high-value herbal medicinal product, registered in the UK for the treatment of stress-induced fatigue, exhaustion and anxiety based on traditional use and used throughout Europe as a herbal medicinal product for similar indications. Numerous unregistered supplements are also available. There are several Chinese species used in traditional Chinese medicine (TCM), including Rhodiola crenulata (Hook.f. & Thomoson) that is believed to be a common adulterant in the R. rosea value chain.

Aims

The project is embedded in a larger study aiming to investigate the diverse value chains that lead to the production of R. rosea as an herbal medicinal product or supplement. Here we focus on a comparison of the quality of the finished products and assess any phytochemical variation between products registered under the Traditional Herbal Medicine Products Directive (THMPD) and products obtained from the market without any registration (i.e. generally unlicensed supplements). Our key aim is to establish the extent of the problem in terms of adulteration of consumer products claiming to contain R. rosea (or R. crenulata).

Methods

Approximately 40 commercial products (granulated powders and extracts) were sourced from different suppliers. We analysed these samples using high performance thin layer chromatography (HPTLC), mass spectrometry (MS) and 1H NMR spectroscopy coupled with multi-variate analysis software following a method previously developed by our group for the analysis of turmeric products.

Results

We investigate the phytochemistry of the different species and assess the potential of R. crenulata as an adulterant at the end of the R. rosea value chains. The consistency of the products varies significantly. Approximately one fifth of commercial products that claimed to be R. rosea did not contain rosavin (the key reference markers used to distinguish R. rosea from related species). Moreover some products appeared not to contain salidroside, another marker compound found in other Rhodiola species. Approximately 80% of the remaining commercial products were lower in rosavin content than the registered products and appeared to be adulterated with other Rhodiola species.

Conclusions

The variation in phytochemical constituents present in Rhodiola products available to European buyers via the internet and other sources is a major cause for concern. Adulteration with different species, and other sometimes unknown adulterants, appears to be commonplace. Good quality systems and manufacturing practices, including those required under the THMPD, enable consumers to have confidence that products are authentic and meet a high specification for quality and safety.

Du Tadalafil pour maigrir?

03/03/2016 | Etudes Compléments alimentaires et Etudes Perte de poids et Etudes Anti-âge et Etudes sur les boosters sexuels et la sexualité

 

Tadalafil reduces visceral adipose tissue accumulation by promoting preadipocytes differentiation towards a metabolically healthy phenotype: Studies in rabbits
Elena Maneschi               Molecular and Cellular Endocrinology Volume 424, 15 March 2016, Pages 50–70

Highlights
• Tadalafil reduced visceral fat accumulation (VAT) in an animal model of MetS.
• Tadalafil dosing induced the expression of UCP1 (brown-fat marker) in visceral fat.
• Tadalafil improved insulin sensitivity in preadipocytes (PAD) isolated from VAT.
• Tadalafil promoted PAD differentiation towards a metabolically healthy phenotype.


Development of metabolically healthy adipocytes within dysfunctional adipose tissue may represent an attractive way to counteract metabolic syndrome (MetS). In an experimental animal model of high fat diet (HFD)-induced MetS, in vivo, long- and short-term tadalafil treatments were able to reduce visceral adipose tissue (VAT) accumulation and hypertriglyceridemia, and to induce the expression in VAT of the brown fat-specific marker, uncoupling protein 1 (UCP1). VAT preadipocytes (PAD), isolated from the tadalafil-treated HFD rabbits, showed: i) a multilocular morphology; ii) an increased expression of brown fat-specific genes (such as UCP1 and CIDEA); iii) improved mitochondrial structure and dynamic and reduced superoxide production; iv) improved insulin sensitivity. Similar effects were obtained after in vitro tadalafil treatment in HFD rPAD. In conclusion, tadalafil counteracted HFD-associated VAT alterations, by restoring insulin-sensitivity and prompting preadipocytes differentiation towards a metabolically healthy phenotype.

Quels sont les effets secondaires court terme des suppléments?

14/10/2015 | Etudes Compléments alimentaires et Etudes Perte de poids et Etudes Anti-âge et Etudes sur les boosters sexuels et la sexualité

 

J’ai l’impression de vivre dans un monde de dingo!
Pépé qui s’étouffe avec son multivitamines, les mecs qui laissent les trucs à la portée des enfants et les jeunes qui font des méga-doses de boosters

Emergency Department Visits for Adverse Events Related to Dietary Supplements
Andrew I. Geller         N Engl J Med 2015; 373:1531-1540 October 1

Dietary supplements, such as herbal or complementary nutritional products and micronutrients (vitamins and minerals), are commonly used in the United States, yet national data on adverse effects are limited.
METHODS: We used nationally representative surveillance data from 63 emergency departments obtained from 2004 through 2013 to describe visits to U.S. emergency departments because of adverse events related to dietary supplements.

RESULTS: On the basis of 3667 cases, we estimated that 23,005 (95% confidence interval [CI], 18,611 to 27,398) emergency department visits per year were attributed to adverse events related to dietary supplements. These visits resulted in an estimated 2154 hospitalizations (95% CI, 1342 to 2967) annually. Such visits frequently involved young adults between the ages of 20 and 34 years (28.0% of visits; 95% CI, 25.1 to 30.8) and unsupervised children (21.2% of visits; 95% CI, 18.4 to 24.0). After the exclusion of unsupervised ingestion of dietary supplements by children, 65.9% (95% CI, 63.2 to 68.5) of emergency department visits for single-supplement–related adverse events involved herbal or complementary nutritional products;

31.8% (95% CI, 29.2 to 34.3) involved micronutrients.

Herbal or complementary nutritional products for weight loss (25.5%; 95% CI, 23.1 to 27.9) and increased energy (10.0%; 95% CI, 8.0 to 11.9) were commonly implicated.

Weight-loss or energy products caused 71.8% (95% CI, 67.6 to 76.1) of supplement-related adverse events involving palpitations, chest pain, or tachycardia, and 58.0% (95% CI, 52.2 to 63.7) involved persons 20 to 34 years of age.
Among adults 65 years of age or older, choking or pill-induced dysphagia or globus caused 37.6% (95% CI, 29.1 to 46.2) of all emergency department visits for supplement-related adverse events;
micronutrients were implicated in 83.1% (95% CI, 73.3 to 92.9) of these visits.

CONCLUSIONS: An estimated 23,000 emergency department visits in the United States every year are attributed to adverse events related to dietary supplements. Such visits commonly involve cardiovascular manifestations from weight-loss or energy products among young adults and swallowing problems, often associated with micronutrients, among older adults.

Le sport modifie t’-il la sensibilité à la caféine?

04/10/2015 | Etudes Compléments alimentaires et Etudes Perte de poids et Etudes Anti-âge et Etudes sur les boosters sexuels et la sexualité

 

Regular physical activity attenuates the hypertensor effects of acute caffeine ingestion
Rogério N. Soares             Appl. Physiol. Nutr. Metab. Vol. 40, 2015   S62

The aim of this study was to evaluate whether regular physical activity
modifies cardiovascular system responses to acute caffeine ingestion.
Sixty subjects (19–50 years) underwent an interventional, quasi experimental
study. They were analysed according to physical activity
status: sedentary and physically active. To evaluate the influence of
caffeine consumption, they were also divided into four groups:
sedentary non-habitual light caffeine consumer (S),
sedentary habitual heavy caffeine consumer (SC)
, physically active non-habitual lightcaffeine consumer (A) and
physically active habitual heavy caffeine consumer (AC).

All groups had their cardiovascular parameters measured
before (basal) and 1 hour after caffeine ingestion (6 mg/kg of body
mass).

It was observed that 1 hour after caffeine ingestion the resting
heart rate (HR) from all subjects of the study decreased (p

< 0.05; 11%).
When comparing the subjects by physical activity status, it was observed
that

only sedentary subjects had their diastolic blood pressure
(DBP) increased
(p < 0.05). The basal and post DBP were lower in AC
than SC. Experimental groups showed differences in HR variation:
S (-6.9 ± 6.3 bpm) vs. A (-3.4 ± 6.5 bpm) (p < 0.05) and A (-3.4 ± 6.5 bpm)
vs. AC (-9.5 ± 7.9 bpm) (p < 0.05).

The regular practice of physical activity may protect against the hypertensor effects of caffeine ingestion.
However, its association with habitual caffeine consumption
may also make the cardiovascular system more sensitive to caffeine,
increasing bradycardia induced by acute caffeine ingestion.

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