Reproductive Health

Why we need to make more of an effort to understand sperm

Sperm are the key to the future of fertility – and contraception.

Despite the huge global demand for both fertility treatment and contraception, there are surprisingly few options to boost male fertility, or for male contraception. To have more options, we really need a better understanding of how human sperm work. Unfortunately, they are incredibly difficult to study in the lab.

Not only are sperm the smallest cells in the body (25 times smaller than a grain of sand), they are unique and highly specialised, designed to survive outside the body. Unlike other cells, sperm contain virtually no cytoplasm – the jelly-like fluid that fills a cell and stores many of the chemicals that are essential for life. Instead they interact with the surrounding environment to inform their behaviour. Their internal chemical messages and signals are also different to those of other cells, meaning we can’t make assumptions about how they work and many standard cell research techniques can’t be applied in the lab. It’s little wonder then that research in the field of male fertility and contraception is limited.

Growing infertility

Infertility is estimated to affect about one in seven couples of reproductive age in the United Kingdom. Male fertility problems are increasingly common. However, our limited understanding of how sperm work and the requirements needed to achieve fertilisation, means that we struggle to treat this problem.

Incredibly, there is no drug that an infertile man can take, or that can be added to his sperm in a laboratory to improve how sperm swim or work. Instead couples rely on treatments such as in vitro fertilisation or IVF and intracytoplasmic sperm injection or ICSI, which are expensive, invasive, and not guaranteed to succeed. Nonetheless, the number of people seeking IVF and ICSI treatment is increasing each year.

Although access to female contraception varies considerably across the globe, use of male methods (condoms, vasectomy) is consistently low. There has been no significant innovation in available male contraception in the past 50 years. Hormonal and non-hormonal methods have been researched since the 70s, but side effects were too severe for implementation.

An immobilized ejaculated spermatozoon is inserted into a human oocyte. (Image: Eugene Ermolovich/Wikimedia Commons)
An immobilized ejaculated spermatozoon is inserted into a human oocyte. (Image: Eugene Ermolovich/Wikimedia Commons)

New, safe, effective and acceptable contraceptive methods for men would help to address the needs of couples who do not, or cannot, use currently available methods. Having a wider choice of contraceptives is also known to increase uptake of all methods. Perhaps more significant is the potential to give men increased options in family planning, leveling the gender inequality in this area.

Silent swimmers

There is a real demand – and an unmet need – for the development of new treatments for both male infertility and family planning. But, before we can tackle these global health issues, we need to understand how sperm work. Without this detailed knowledge, and a potential target for a drug to work on, it is virtually impossible to develop new compounds to enhance, or inhibit, sperm function.

Sperm swimming (motility) is probably its most important characteristic. Although the underlying cellular mechanisms are not fully understood, changes in levels of calcium inside the sperm cell are known to be crucial to sperm function, including swimming and fertilisation. Fluctuations in the level of calcium within sperm cells is known to be due to specific membrane pores (ion channels) in the sperm tail – these pores are called CatSper.

A swimming sperm. From video by Kantsler et al. (CC BY 3.0)
A swimming sperm. From video by Kantsler et al. (CC BY 3.0)

High-throughput screening or HTS is an approach used by the pharmacology industry to discover new drugs, where automated experiments can examine thousands of compounds to “screen” for a desired effect. Compounds that show the desired effect are called “hits”.

We recently published a paper describing a HTS approach to look for new drugs to treat male infertility. Calcium inside sperm was fluorescently labelled, and levels then measured in response to a number of new drug compounds.

We screened more than 3,400 compounds and identified 48 hits, that showed the effects we needed. Further testing of several of these hit compounds found two that showed improved function and swimming in sperm, probably due to an effect on CatSper channels.

A potential cure

Although the original experiments used sperm from healthy volunteers, the researchers also saw enhanced function and swimming when they tested both compounds on samples from patients undergoing IVF. Given the lack of progress in treating male infertility to date, this is a promising find, even if it is very early days.

The beauty of this finding is that the compounds that we found would only act on sperm cells, because the ion channel “CatSper” is unique to sperm. This could help to avoid unwanted side effects, which makes these compounds attractive clinically and commercially. While this research has been directed at drug discovery for male fertility, it is possible to turn the concept around and find compounds that inhibit sperm swimming, thereby creating a new male contraceptive.

This is an advance that potentially offers hope to millions of couples worldwide, but there is still much that we need to know and understand to unlock the workings of the human sperm.

Sarah Martins da Silva, Consultant Gynaecologist and Senior Lecturer In Reproductive Medicine, University of Dundee.

This article first appeared on The Conversation.

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Advice from an ex-robber on how to keep your home safe

Tips on a more hands-on approach of keeping your house secure.

Home, a space that is entirely ours, holds together our entire world. Where our children grow-up, parents grow old and we collect a lifetime of memories, home is a feeling as much as it’s a place. So, what do you do when your home is eyed by miscreants who prowl the neighbourhood night and day, plotting to break in? Here are a few pre-emptive measures you can take to make your home safe from burglars:

1. Get inside the mind of a burglar

Before I break the lock of a home, first I bolt the doors of the neighbouring homes. So that, even if someone hears some noise, they can’t come to help.

— Som Pashar, committed nearly 100 robberies.

Burglars study the neighbourhood to keep a check on the ins and outs of residents and target homes that can be easily accessed. Understanding how the mind of a burglar works might give insights that can be used to ward off such danger. For instance, burglars judge a house by its front doors. A house with a sturdy door, secured by an alarm system or an intimidating lock, doesn’t end up on the burglar’s target list. Upgrade the locks on your doors to the latest technology to leave a strong impression.

Here are the videos of 3 reformed robbers talking about their modus operandi and what discouraged them from robbing a house, to give you some ideas on reinforcing your home.

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2. Survey your house from inside out to scout out weaknesses

Whether it’s a dodgy back door, a misaligned window in your parent’s room or the easily accessible balcony of your kid’s room, identify signs of weakness in your home and fix them. Any sign of neglect can give burglars the idea that the house can be easily robbed because of lax internal security.

3. Think like Kevin McCallister from Home Alone

You don’t need to plant intricate booby traps like the ones in the Home Alone movies, but try to stay one step ahead of thieves. Keep your car keys on your bed-stand in the night so that you can activate the car alarm in case of unwanted visitors. When out on a vacation, convince the burglars that the house is not empty by using smart light bulbs that can be remotely controlled and switched on at night. Make sure that your newspapers don’t pile up in front of the main-door (a clear indication that the house is empty).

4. Protect your home from the outside

Collaborate with your neighbours to increase the lighting around your house and on the street – a well-lit neighbourhood makes it difficult for burglars to get-away, deterring them from targeting the area. Make sure that the police verification of your hired help is done and that he/she is trustworthy.

While many of us take home security for granted, it’s important to be proactive to eliminate even the slight chance of a robbery. As the above videos show, robbers come up with ingenious ways to break in to homes. So, take their advice and invest in a good set of locks to protect your doors. Godrej Locks offer a range of innovative locks that are un-pickable and un-duplicable. To secure your house, see here.

The article was produced by the Scroll marketing team on behalf of Godrej Locks and not by the Scroll editorial team.