Every now and then we hear about
a specific gene that may be the key for developing a condition. Although this
type of reporting tends to simplify complex disorders and the specific
processes required for them to develop, it also often highlights some specific
areas worthy of additional attention within research. One protein that has been
considered in various studies by both GlaxoSmithKline (GSK) and Palatin Technologies
is the so-called MC4 receptor.
The MC4 receptor, which has been
linked to erectile dysfunction and insulin resistance in the past, is also
known for being the most consistent finding in genetic research on early onset
obesity. There appears to be some evidence that MC4 has a role in the regulation
of metabolism and some individuals may have several mutations of this receptor.
The current view suggests that the more mutations of the MC4-receptor, the higher
the risk of developing obesity.
Given the complexity of how the
MC4-receptor works, there have been no successful studies to date that have
developed an obesity treatment that could be safe for humans to use.
Specifically, within studies that have centred on the use of drugs that
directly activate MC4-receptors there have been some concerns about increasing
blood pressure (we have previously written about Bremelanotide, which falls
into this category). However, in an
attempt to potentially circumvent the blood pressure risks, GSK has utilised a
different strategy where the researchers would rely on so-called positive allosteric
modulators to activate the MC4-receptors rather than activating them directly.
In contrast to what has been
reported by some news outlets, the treatment GSK is seeking to develop would
not be an all-round cure for obesity. Instead, it would be a treatment to
manage the obesity some individuals have developed due to a genetic
vulnerability. No matter how pleased we are to hear that medical companies are
pursuing obesity research, we cannot stress enough that a genetic vulnerability
does not mean that environmental factors can be ignored. Developing obesity
occurs as a result of a multitude of factors, but the most common cause is that
energy consumption over time is greater than energy expended. No matter what medications
are developed to assist weight loss in obese patients, we cannot pretend that a
lifestyle change is not essential for most people who are obese.
It
is unlikely that the treatments GSK is developing will be on the market within
the near future. The study itself is expected to run for 3 years and once the
findings have been published further clinical trials will be needed to
establish the safety of the treatment and corroborate the study’s findings.