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Tag: metabolites

Fasting boosts human metabolism, has anti-aging effects

In the advent of 2019, we are inspired to set new goals, pursue life-long dreams, or simply make better choices. Perhaps, one of the most common reveries we wish to realize is to be able to adopt a healthier kind of lifestyle. With this in mind, some of us look for ways to feel dutifully healthier, such as by managing our weight. So, many would turn to fad diets and caloric restrictions that promise to help. One of them is intermittent fasting. Based on studies, intermittent fasting does not only help trim weight but it seems to offer further health benefits as well.

 

 

 

Intermittent fasting – overview

 

intermittent fasting
Scientists found that fasting boosted human metabolism. This could mean that fasting may slow aging in humans. [Image credit: Zeyus Media]

 

 

In May 2018, I wrote the article: Intermittent Fasting – benefits and caution. There, I tackled briefly about intermittent fasting, its benefits, and potential risk. In essence, intermittent fasting is a cyclic pattern of a period of fasting and a subsequent period of non-fasting. The most common forms are: (1) whole-day fasting and (2) time-restricted eating. Whole-day fasting entails one-full day of “no eating”, done twice a week (thus, referred to as “5:2 plan“). In time-restricted eating, there is an interval of fasting and non-fasting on a daily basis. It could be half a day of fasting, and then the remaining half as the non-fasting period.  With intermittent fasting, it’s not so much about “what to eat…” or “how much…” Rather, it’s more about a question of when.

 

 

 

Intermittent fasting became popular because it does not only help curb weight but it also implicates other health benefits. It apparently slows aging and boosts the immune defense.[1] However, as I pointed out in that article, caution should still be taken. Intermittent fasting is not for everyone, especially those who are immunocompromised and underweight.[2]

 

 

 

Rejuvenating effects of fasting

Previously, I mentioned that studies confirming the health benefits of fasting were done on non-human subjects (e.g. rodent models). Without much scientific proofs of efficacy on humans, what would, therefore, be definite is doubt.  However, on January 29 of this year, a team of scientists from Okinawa Institute of Science and Technology Graduate University (OIST) and Kyoto University reported rejuvenating effects of fasting on human subjects. They published their findings in Scientific Reports.[3] Accordingly, they analyzed the blood samples from four fasting individuals. They also monitored the levels of metabolites involved in growth and energy metabolism. What they found was quite interesting and promising.

 

 

 

Dr. Takayuki Teruya, one of the researchers of the team, said that their results implicated the rejuvenating effects of fasting. They found that many metabolites increased significantly, about 1.5- to 60-fold, in just 58 hours of fasting. In their previous study, they identified some of these metabolites (e.g. leucine, isoleucine, and ophthalmic acid), that typically deplete with age. According to Dr. Teruya, they found that the amount of these metabolites increased again in individuals who fasted. Also, they conjectured that fasting could possibly promote muscle maintenance and antioxidant activity based on the metabolites they found. Hence, fasting may probably promote longevity as well. Dr. Teruya further said that this was not yet known until now since most studies that have said so used animal models.[4]

 

 

 

Fasting increased metabolism

During fasting, the body turns to alternate energy stores when carbohydrates are not available. Thus, the less-common metabolites from alternative metabolic pathways superseded the typical metabolites from carbohydrate metabolism. They identified butyrates, carnitines, and branched-chain amino acids as some of the metabolites that accumulated during fasting. [4] Apart from this, the researchers also found an increase in Citric acid cycle intermediates. This means that aside from prompting alternate metabolic pathways, fasting has also augmented the common metabolic activities. The metabolism of purine and pyrimidine seemed also heightened, indicating an increase in gene expression and protein synthesis. Because of this, the researchers also saw a boost in antioxidants (e.g. ergothioneine and carnosine) that protect cells from the free radicals produced by metabolism. The researchers assume to be the first to provide evidence of antioxidants as a fasting marker. [4]

 

 

 

This new-found proof infers that fasting seems to have some anti-aging effects, this time, on human subjects. Their next step is to see if they could duplicate the results in a larger-scale study. For now, let us remain cautious, look for indubitable substantiation, and weigh in the benefits and risks of all available options.

 

 

 

— written by Maria Victoria Gonzaga

 

 

References:

 

1  Cohut, M. (2018). Intermittent fasting may have ‘profound health benefits’. Retrieved from [Link]

2  Longo, V. D., & Mattson, M. P. (2014). Fasting: Molecular Mechanisms and Clinical Applications. Cell Metabolism, 19 (2), 181–192. [Link]

3 Teruya, T., Chaleckis, R., Takada, J., Yanagida, M. & Kondoh, H. (2019). Diverse metabolic reactions activated during 58-hr fasting are revealed by non-targeted metabolomic analysis of human blood. ”Scientific Reports, 9”(1) DOI: 10.1038/s41598-018-36674-9.

4  ‌ Okinawa Institute of Science and Technology (OIST) Graduate University. (2019, January 31). Fasting ramps up human metabolism, study shows. ScienceDaily. Retrieved from [Link]

Electrochemical simulation of triclosan metabolism and toxicological evaluation

Triclosan is a broad spectrum antibacterial or antifungal agent found in some consumer products. Such as in antiseptic soaps, toothpaste, detergents, cosmetics, plastic kitchenware, carpets, socks and toys. Pharmaceuticals and personal care products raise concerns in recent years about triclosan potential threats to human health and ecosystem. The demand of triclosan globally continues to increase and its production exceeded to 1500 tons per year worldwide. Given its widespread application it has been detected in wastewater, soil, sediment and surface water. Hence, the purpose of this research study is to investigate phase I metabolism of triclosan using electrochemical simulation. Also it tends to examine toxicological effects and its metabolites.

 

Toxicological evaluation of Triclosan

Using the QSAR modeling tool was performed to evaluate the toxic potential values  on the tested compound. In which the specific adverse effects were predicted by analyzing binding affinity towards each protein. Toxicological effects of triclosan on zebrafish embryos include delay of otolith formation, spine malformation, pericardial edema and late eyes formation. Some other notable changes are retardation of eye, hemorrhage, yolk-sac shrinkage and low heartbeat rate. Clearly, toxicological effects of triclosan on zebrafish are consistent to other research studies in literature. Moreover, it also shows that metabolites may induce similar adverse effects particularly the cardiovascular disorder.

 

Indeed, the research study was successfully simulated triclosan metabolism using electrochemical evaluation and its metabolites using modeling tools and bioassays. There were eight potential metabolites  were form via hydroxylation, ether cleavage and cyclization. Two dioxin derivatives were discovered for the first time and acts as potential metabolites. However, after the electrochemical reaction leads to induced high toxicity on zebrafish embryos. Therefore, the changes of acute toxicity through three transformation pathways indicate that only ether-bond can detoxify triclosan. While other transformation products formed highly toxic.

 

Hence, the study highlights that triclosan and its metabolites can cause serious effects in aquatic ecosystem if it is used continuously. It should be regulated in products utilization and considered as the major contaminants in the environment. To avoid further damaged and disruption especially to aquatic organisms and even to humans. Since most of the products containing triclosan are rinsed down and enter into sewerage and waste effluent.

 

Source: Prepared by Joan Tura from Science of the Total Environment

Volumes 622–623, 1 May 2018, Pages 1193-1201