There's a growing body of evidence that gold nanoparticles can offer significant, targeted weight loss that focuses on fat (lipid) tissue, without affecting muscle structure. What's more, there are added health bonuses, including anti-inflammatory properties and improvements in blood glucose levels.
Scientists from Egypt's Alexandria University have furthered what we know about gold nanoparticles (AuNPs), demonstrating that weekly doses have the potential to lead to significant weight loss – perhaps even more than the GLP-1 class of medications – and, unlike those drugs, showed no evidence of muscle wastage.
But, there is a catch. The numbers are impressive – 36% targeted fat loss over nine weeks, compared to the typical 10-20% reduction of body weight seen in those taking GLP-1 drugs (with up to 20% of that being muscle loss) – yet so far the scientists have only conducted animal studies. This research, however, gets the novel obesity treatment a step closer to a human trial.
In the rat study, the researchers compared different doses of AuNPs, with a control (no treatment) and existing weight-loss drug orlistat (brand name Xenical). The diet-induced obese rats were assigned one of these treatment groups and treated for nine weeks, after which their body composition, organ health and metabolic markers were assessed.
What they found was that high weekly doses of AuNPs significantly reduded body fat, increased muscle mass and boosted metabolic markers in obese animals. Like in previous studies, there was also evidence of improved blood sugar levels, and reduced inflammation and oxidative stress. Histological assessment also revealed that AuNPs repaired liver and kidney tissue – while orlistat adversely affected these organs.
Through bioelectrical impedance analysis (BIA), a common non-invasive method of measuring the body's fat mass (FM), fat-free mass (FFM) and total body water (TBW), the researchers found that AuNPs were also able to target the right lipid cells. The high weekly dose group saw an average of 36% fat loss, which was more effective than daily high doses (33%), and significantly better than the rats on orlistat (18%). Essentially, twice as impactful.
“BIA and dissection measurements of body-composition showed that high doses of AuNPs treatment significantly lowered body fat and improved fat-free mass, making it a potential alternative to current obesity treatments," the researchers noted. “While earlier studies have shown that orlistat can reduce obesity-related weight gain, AuNPs are a more effective anti-obesity treatment due to their anti-inflammatory and antioxidant effects, as well as their ability to accumulate in adipose tissues.”
In a world where GLP-1 drugs exist, it can be easy to forget that there are other medications out there, such as orlistat. It's also nothing like Wegovy or Ozempic, instead helping block the role of lipid (fat) absorption. While results are more modest long-term than GLP-1 medications – individuals lose around 6% of their body weight – it's a significantly cheaper option and an alternative to those who encounter serious side effects from GLP-1s.
There has been no comparison of GLP-1s and AuNPs, however, but given the latter's evidence of muscle protection, it has the potential to be a complementary treatment, not a replacement or direct competitor.
AuNPs have been the focus of a lot of attention over the last decade, and there's a growing interest in unlocking its weight-loss potential. The latest research builds on earlier findings, covered in these 2018 and 2023 studies. AuNPs are currently used in various treatments, such as cancer therapy and in drug delivery, but a human obesity trial remains elusive. This is largely due to health unknowns – such as the potential toxicity of AuNPs.
“Since an estimated 60% of the world’s population may be overweight or obese by 2030, we urgently need innovative therapies for obesity," the researchers added. "Although AuNPs show promise as an obesity treatment, more research is required to decide whether these particles pose a risk to human organs.”
The study was published in the journal Science Reports.
Source: Alexandria University via Nature