The Vices Of Men

By Vincent van Gogh - Scanned from Smoke: a global history of smoking (2004) ISBN 1-86189-200-4, Public Domain, https://commons.wikimedia.org/w/index.php?curid=3857076

The paper linked here is a fascinating review that looks at three major vices of men – drinking alcohol, being overweight/obese, and smoking tobacco – and how these activities can damage male fertility and also negatively affect the health of their offspring. Mechanisms by which these vices can affect fertility and the health of children include epigenetic changes to sperm DNA and non-coding RNA (changes to the modification to DNA and RNA, not including actual sequence mutation, that can affect gene expression), sperm DNA damage (which can cause actual sequence mutation affecting gene expression), changes in sperm chromatin structure (for example, changes in the chromosome structure that can affect which genes are expressed and which are silenced), and changes in seminal plasma (that can affect the function of the sperm cells themselves).  Abstract:

There is growing evidence from animal and human studies that demonstrate that acquired paternal traits can impair both a male's fertility and the health of his offspring, including advanced age, smoking, stress, trauma, under-nutrition, infection, toxin exposure, and obesity. Curiously, many of these factors manifest as impaired neurological, behavioural, and/or metabolic functioning in offspring. The underlying molecular mechanisms that respond to the paternal environment and act as vectors of intergenerational transmission are beginning to emerge. This review focuses on three vices of men (alcohol consumption, overweight/obesity, and tobacco smoking) that damage fertility and pose risks to offspring health. These vices are not only the three most prevalent but are also leading risk factors for death and disability adjusted life years (DALYs) worldwide. Clearly, any epigenetic/genetic alterations induced by the paternal exposures responsible for transmission need to escape/bypass the substantial post-fertilisation reprogramming that occurs during embryo development. For example paternal obesity alters the molecular composition of sperm, alters the developmental trajectory of resultant embryos, and increase the incidence of obesity and metabolic disorders in offspring. Mechanistic candidates of paternal programming include changes to the sperm epigenome (eg DNA methylation, histone/protamine modifications, and sperm borne small non-coding RNAs), increased sperm DNA damage, aberrant sperm DNA chromatin structure, and components of seminal plasma. Understanding the molecular mechanisms underpinning paternal programming may lead to the development of interventions designed to reduce the disease burden in future generations, who were born to fathers exposed to these initiating factors. Given that these vices are predominantly self-inflicted, interventions aimed at mitigating their consequences are readily identified.

Add this information to all the other reasons to avoid these vices.

Toxic Games

“Most Americans believe that if a chemical is in their cosmetics, their coat, or their couch, someone is making sure it is safe for their health”. 

This statement came from a recent Science editorial on toxic materials used in consumer products. I have never paid attention to the doom and gloom people ranting about how we are being poisoned by the profit-driven industries. 

However, the article in the respected Science journal was not written by one of these people: it was written by the researcher Arlene Blum, a collaborator of the legendary Dr. Bruce Ames. 

Probably because of its credibility, the article evoked a great dose of thought about the dangerous chemicals to which I expose my family and myself every day. Some of these agents damage the DNA (causing mutations) and increase the risk of cancer. There are approximately 80,000 industrial chemicals used in commerce in the U.S., and their safety is not exactly well established. 

One of the most well-known ways to distinguish harmless agents from substances that damage the DNA and cause mutations is the test designed by Dr. Ames. The test utilizes a bacterial species that grows only when the amino acid histidine is added to the medium. Therefore, in a medium with very little histidine, the bacteria will grow at the beginning, but as the amino acid is depleted, the bacteria would stop proliferating. However, if to the same medium we add the bacteria along with a substance that causes mutations (changes in DNA), some of the many bacterial cells would undergo mutations and continue to grow even in the absence of the amino acid histidine. This test has proven to be an excellent approach to revealing many substances as mutagenic agents. 

The U.S. still has the intellectual and technical power to identify dangerous agents; however, it is mind-boggling how information on the toxicity of some chemicals takes up to half-century to implement and start to phase out of use. In her Science article, Dr. Blum mentions one such compound – perfluorooctanoic acid (C8). 

Another bitter reminder that we are not well protected from harmful agents came from the same issue of Science, and it was about a pesticide produced by Bayer CropScience. This pesticide (called sometimes Synapse) was given a conditional approval for use by the Environmental Protection Agency (EPA) in 2008, and has been used for more than 200 U.S. crops. Almost eight years later, it seems that we have realized that the insecticide is pretty harmful… The game between the company and EPA is still to take place. 

Anyway, it seems that instead of being immersed in Hunger Games, we are all unwilling participants in the Toxic Games.