SLU-PP-332? The novel exercise mimetic

SLU-PP-332, an exercise mimetic that has garnered a variety of attention amongst hybrid athletes, Body builders and anti-aging/fitness fanatics. 

So what is it? SLUPP332 despite its confusing "jumble" of words and numbers is a novel exercise mimetic. This in short means a molecule or drug that is "designed to simulate the biological benefits of physical exercise without requiring actual physical activity"  (Fan & Evans, 2017). 

Below we will discuss the mechanism of actions as well as accompanied investigational benefits:

1. Binding to Estrogen-Related Receptors (ERRs)

SLU-PP-332 starts by binding to the ERRs (Estrogen-Related Receptors). It binds to the following:

ERRα
ERRβ
ERRγ

So what do these receptors do?

ERRα (Estrogen-Related Receptor Alpha)

ERRα is considered one of the primary regulators of cellular energy metabolism and is highly expressed in tissues with high energy demands, including skeletal muscle, cardiac tissue, brown adipose tissue and the liver (Audet-Walsh & Giguère, 2015). This receptor is heavily involved in regulating genes associated with:

Mitochondrial biogenesis
Fatty acid oxidation
Oxidative phosphorylation
ATP production
Metabolic flexibility

Preclinical evidence suggests that activation of ERRα by SLU-PP-332 may promote the expression of genes involved in transporting fatty acids into the mitochondria, where they can be utilised for energy production (Billon et al., 2023). Through this pathway, SLU-PP-332 is being investigated for its potential to support enhanced mitochondrial function and increased energy expenditure.

ERRγ (Estrogen-Related Receptor Gamma)

ERRγ is highly expressed in oxidative tissues such as skeletal muscle and the heart and is recognised as an important regulator of endurance adaptations (Rangwala et al., 2010). Activation of ERRγ has been associated with:

Increased mitochondrial respiration
Formation of oxidative (Type I) muscle fibres
Enhanced oxygen utilisation
Improved fatigue resistance

Preclinical studies suggest that activation of ERRγ may induce a gene expression profile similar to that observed following endurance exercise, leading researchers to investigate SLU-PP-332 for its potential to promote exercise-like adaptations in skeletal muscle (Billon et al., 2023).

ERRβ (Estrogen-Related Receptor Beta)

ERRβ is currently the least understood of the three receptors and appears to have a comparatively smaller role in systemic energy metabolism (Giguère, 2008). It is expressed in several tissues, including the central nervous system, and is thought to be involved in cellular differentiation and mitochondrial regulation.

While its exact contribution to the activity of SLU-PP-332 remains under investigation, researchers have hypothesised that ERRβ activation may contribute to mitochondrial maintenance and cellular resilience.

2. Recruitment of PGC-1α – The Master Regulator of Mitochondrial Function

Following activation of the ERR receptors, SLU-PP-332 is believed to enhance signalling through Peroxisome Proliferator-Activated Receptor Gamma Coactivator-1 Alpha (PGC-1α), often referred to as the "master regulator" of mitochondrial biogenesis (Puigserver & Spiegelman, 2003).

PGC-1α is naturally upregulated during endurance exercise and acts by increasing the transcription of genes involved in:

Mitochondrial formation
Fat metabolism
Oxidative phosphorylation
Cellular energy production

Because of this, SLU-PP-332 is being investigated for its potential to activate some of the same molecular pathways that are naturally stimulated during prolonged aerobic exercise.

3. Mitochondrial Biogenesis

One of the most intriguing findings from preclinical research is the apparent ability of SLU-PP-332 to increase mitochondrial gene expression (Billon et al., 2023).

Mitochondria are often referred to as the "powerhouses" of the cell, producing the majority of cellular ATP through oxidative phosphorylation.

An increase in mitochondrial number and function has been associated with:

Improved aerobic capacity
Increased cellular energy production
Enhanced metabolic efficiency
Greater utilisation of fatty acids as fuel

These observations have led researchers to investigate SLU-PP-332 for its potential applications in supporting metabolic health and exercise performance.

4. Increased Fatty Acid Oxidation

Activation of the ERR-PGC-1α axis appears to increase the expression of several genes involved in lipid metabolism, including those responsible for transporting fatty acids into the mitochondria and facilitating β-oxidation (Audet-Walsh & Giguère, 2015). Preclinical evidence has demonstrated that treatment with SLU-PP-332 resulted in a metabolic shift favouring fatty acid utilisation over carbohydrate utilisation (Billon et al., 2023).

This has generated interest in SLU-PP-332 as a compound being investigated for its potential to:

-Support metabolic flexibility
-Increase energy expenditure
-Promote utilisation of stored fatty acids
-Mimic certain metabolic aspects of endurance exercise

However, these findings are currently limited to preclinical models and require further investigation in humans.

5. Exercise Mimetic Effects and Endurance Capacity

Perhaps the most notable finding from animal research is that SLU-PP-332 has demonstrated the ability to significantly improve running endurance in mice without requiring prior exercise training (Billon et al., 2023).

Researchers observed that activation of ERR pathways resulted in a skeletal muscle profile resembling that of endurance-trained animals, characterised by:

-Greater mitochondrial density
-Increased oxidative muscle fibres
-Enhanced aerobic metabolism
-Improved fatigue resistance

These findings have led to considerable interest in SLU-PP-332 as a potential exercise mimetic. Nevertheless, it is important to recognise that actual exercise provides numerous physiological benefits—including mechanical loading, cardiovascular conditioning and neuromuscular adaptations—that cannot currently be replicated by a single molecule.

Conclusions:

SLU-PP-332 represents an exciting area of metabolic and exercise physiology research. Through activation of the ERRα, ERRβ and ERRγ pathways and subsequent stimulation of PGC-1α signalling, the compound is being investigated for its potential to support mitochondrial function, fatty acid oxidation and endurance-related adaptations. While preclinical findings are certainly promising, it is important to emphasise that SLU-PP-332 remains an investigational compound and there are currently no published human clinical trials establishing its efficacy or long-term safety profile. Further research will be necessary to determine whether these promising preclinical findings translate into meaningful effects in humans.

 

 

Reference list  (Please note this reference list format below has been created with the use of an AI related APA 7th Edition tool)

Audet-Walsh, É., & Giguère, V. (2015). The multiple universes of estrogen-related receptor alpha and gamma in metabolic control and related diseases. Acta Pharmacologica Sinica, 36(1), 51–61. https://doi.org/10.1038/aps.2014.121

Billon, C., Sitaula, S., Burris, T. P., & colleagues. (2023). An exercise mimetic activates estrogen-related receptors and induces endurance adaptations in mice. ACS Chemical Biology, 18(10), 2470–2481. https://doi.org/10.1021/acschembio.3c00428

Fan, W., & Evans, R. M. (2017). Exercise mimetics: Impact on health and performance. Cell Metabolism, 25(2), 242–247. https://doi.org/10.1016/j.cmet.2017.01.001

Giguère, V. (2008). Transcriptional control of energy homeostasis by the estrogen-related receptors. Endocrine Reviews, 29(6), 677–696. https://doi.org/10.1210/er.2008-0017

Puigserver, P., & Spiegelman, B. M. (2003). Peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC-1α): Transcriptional coactivator and metabolic regulator. Endocrine Reviews, 24(1), 78–90. https://doi.org/10.1210/er.2002-0012

Rangwala, S. M., Wang, X., Calvo, J. A., Lindsley, L., Zhang, Y., Deyneko, G., Beaulieu, V., Gao, J., Turner, G., & Markovits, J. (2010). Estrogen-related receptor gamma is a key regulator of muscle mitochondrial activity and oxidative capacity. The Journal of Biological Chemistry, 285(29), 22619–22629. https://doi.org/10.1074/jbc.M110.125401