Alamandine: A New Peptide Player in Regenerative Research

The human body is an intricate symphony of biological systems, and among the most fascinating is the renin-angiotensin system (RAS), long known for its role in regulating blood pressure. But imagine if this system had a 'good twin' – a protective arm working to balance out the more aggressive components. Enter Alamandine, a peptide that's rapidly emerging from the shadows of this complex system, hinting at remarkable regenerative and protective capabilities across a spectrum of health challenges. Researchers are buzzing about its potential, and the findings so far paint a vivid picture of a peptide with diverse effects, from tackling fibrosis to supporting brain health.

What is Alamandine?

Alamandine is a fascinating peptide, a relatively new discovery within the intricate web of the renin-angiotensin system (RAS) (PMID 29541937, PMID 38362781). While the classical RAS pathway is known for generating angiotensin II, which can increase blood pressure and promote fibrosis, Alamandine belongs to the 'alternative' or 'protective' arm of this system (PMID 38362781). It's formed when the amino-terminal aspartic acid of angiotensin-(1-7) is decarboxylated (PMID 38362781). Once formed, Alamandine exerts its effects by activating a specific receptor known as the Mas-related G-protein-coupled receptor D (MrgD) (PMID 38362781).

This protective arm of the RAS, including Alamandine and its receptor MrgD, often acts in opposition to the classical RAS pathway, helping to maintain cardiovascular homeostasis and protect against various forms of damage (PMID 38362781, PMID 27456244). Essentially, if angiotensin II is the accelerator, Alamandine and its kin could be considered the brakes, helping to keep the body's systems in balance.

Why researchers are excited

The excitement around Alamandine stems from its potential to counteract several detrimental processes associated with common chronic diseases. Unlike some RAS components that drive high blood pressure and tissue damage, Alamandine has demonstrated effects that suggest it could be a valuable tool in regenerative and protective medicine (PMID 29541937, PMID 27456244).

Researchers are particularly interested in its ability to influence cellular metabolism, reduce inflammation, and protect vital organs. For instance, its observed impact on fibroblast activation, a key driver of scarring and organ damage in conditions like pulmonary fibrosis, positions it as a promising candidate for anti-fibrotic strategies (PMID 36635651). Furthermore, the discovery of a newly identified product, Alamandine-(1-5), with significant blood pressure-lowering effects, adds another layer of intrigue to its therapeutic potential (PMID 41221580). The fact that it shows promise in areas like Alzheimer's disease and has antiproliferative effects on certain cancer cells further expands the scope of its potential applications (PMID 40853487, PMID 35652611).

What the studies found

Research into Alamandine, though still emerging in some areas, has unveiled a compelling range of findings across various experimental models.

| Study | Model | Key finding | PMID | | :----------------------------------------------- | :---------------------------------------------------- | :------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | :----------- | | Alamandine/MrgD axis prevents TGF-β1-mediated fibroblast activation via regulation of aerobic glycolysis and mitophagy | *In vitro* (lung fibroblasts), *in vivo* (bleomycin-induced fibrosis in animals) | Prevented TGF-β1-mediated fibroblast activation by repressing glycolysis and reversing impaired mitophagy in lung fibroblasts, and counteracted effects of bleomycin on key markers of fibrosis and metabolism *in vivo* (PMID 36635651). | 36635651 | | Angiotensin-(1-7) and Alamandine on Experimental Models of Hypertension and Atherosclerosis | Experimental models of hypertension | Showed endothelial-dependent vasorelaxation via nitric oxide and hypotensive effects in experimental hypertension in animals (PMID 29541937). | 29541937 | | Alamandine Rescues Cognitive Impairment and Ameliorates Alzheimer's Disease-Like Neuropathology in APP/PS1 Mice | APP/PS1 mice (animal model of Alzheimer's disease) | Mitigated cognitive function and spatial learning impairment, ameliorated tau protein phosphorylation, suppressed neuroinflammation, and reduced oxidative stress, ferroptosis, and endoplasmic reticulum stress in the brains of APP/PS1 mice (PMID 40853487). | 40853487 | | Phosphoproteomic studies of alamandine signaling in CHO-MrgD and human pancreatic carcinoma cells | Tumoral cell lines (Mia PaCa-2, A549), nontumoral cell lines (HaCaT, CHO, CHO-MrgD) | Reduced proliferation of tumoral cell lines in a MrgD-dependent manner, shifting them from anaerobic to aerobic metabolism, negatively regulating the PI3K/AKT/mTOR pathway, and activating FoxO1 (PMID 35652611). No effect observed in nontumoral cell lines tested (PMID 35652611). | 35652611 | | Identification and Characterization of Alamandine-(1-5), a New Component of the Renin-Angiotensin System | *In vivo* (normotensive and spontaneously hypertensive rats), *in vitro* (isolated blood vessels, hearts, cardiomyocytes, cell culture) | Alamandine-(1-5), a product of Alamandine, was found in circulation, increased baroreflex sensitivity, and produced a long-lasting antihypertensive effect in spontaneously hypertensive rats in animals. It decreased inotropism in isolated hearts and reduced contractility in cardiomyocytes (PMID 41221580). | 41221580 |

How it's thought to work

Alamandine's mechanism of action is multifaceted, primarily revolving around its interaction with the Mas-related G-protein-coupled receptor D (MrgD) (PMID 38362781, PMID 36635651). This receptor activation appears to orchestrate a cascade of beneficial cellular responses.

One of the most significant pathways involves its impact on cellular metabolism. In models of idiopathic pulmonary fibrosis, the Alamandine/MrgD axis was found to prevent fibroblast activation by repressing aerobic glycolysis – the process where cells generate energy through glucose breakdown – and by regulating mitophagy, which is the selective degradation of damaged mitochondria (PMID 36635651). Specifically, Alamandine reduced the expression of glycolysis-related proteins like HK2 and PFKFB3 and reversed the enhancement of glycolysis caused by blocking the autophagic degradation of these proteins (PMID 36635651). It also reversed the moderation of Parkin/LC3-mediated mitophagy, which otherwise promotes glycolysis (PMID 36635651).

In the context of Alzheimer's disease in animal models, Alamandine was shown to mitigate cognitive impairment by addressing several critical factors: reducing the phosphorylation of tau proteins, suppressing neuroinflammation, and alleviating oxidative stress, ferroptosis, and endoplasmic reticulum stress (ERS) (PMID 40853487).

For its antiproliferative effects in tumoral cells, Alamandine appears to induce a metabolic shift from anaerobic to aerobic metabolism (PMID 35652611). It also negatively regulates the PI3K/AKT/mTOR pathway and activates the transcriptional factor FoxO1, both of which are critical in controlling cell growth and survival (PMID 35652611).

Alamandine also acts as a vasodilator, contributing to hypotensive effects by increasing nitric oxide release from the endothelium (PMID 29541937, PMID 27456244). Interestingly, a newly identified product, Alamandine-(1-5), can bind and stimulate nitric oxide production through multiple receptors in the RAS protective arm (Mas, MrgD, and AT2 receptors), with its effects on cardiomyocytes and aortic rings being abolished by MrgD genetic deletion in animals (PMID 41221580).

The catch: what we still don't know

While the initial findings for Alamandine are exciting, it's crucial to remember that much of this research is in its early stages. Many of the impressive results highlighted come from *in vitro* (cell culture) studies or *in vivo* animal models (PMID 36635651, PMID 40853487, PMID 35652611). While these provide valuable insights, they do not directly translate to human health outcomes.

For instance, while Alamandine shows promise in experimental models of hypertension and atherosclerosis (PMID 29541937), the amount of research on its effects in atherosclerosis, in particular, is still limited (PMID 29541937). Similarly, the discovery of Alamandine-(1-5) and its blood pressure-lowering effects in rats is a significant step, but further research is needed to understand its full biological activity and implications in humans (PMID 41221580).

Researchers are still piecing together the full spectrum of Alamandine's interactions within the complex RAS and beyond. The future will require more extensive research, including human clinical trials, to fully understand its safety, efficacy, and therapeutic potential.

Keep exploring

Alamandine represents a thrilling frontier in peptide research, offering a glimpse into the body's own protective mechanisms. As scientists continue to unravel its intricate roles and potential applications, the landscape of regenerative medicine looks increasingly bright.

Dive deeper into the world of peptides! Explore our A–Z protocols to learn about other cutting-edge compounds, compare their mechanisms, and share this article to spread the word about these incredible discoveries.

Sources

* Alamandine/MrgD axis prevents TGF-β1-mediated fibroblast activation via regulation of aerobic glycolysis and mitophagy. Journal of translational medicine, 2023. https://pubmed.ncbi.nlm.nih.gov/36635651/ * Alternative Renin-Angiotensin System. Hypertension (Dallas, Tex. : 1979), 2024. https://pubmed.ncbi.nlm.nih.gov/38362781/ * Angiotensin-(1-7) and Alamandine on Experimental Models of Hypertension and Atherosclerosis. Current hypertension reports, 2018. https://pubmed.ncbi.nlm.nih.gov/29541937/ * Recent advances in the pathophysiology of hypertension. Physiology (Bethesda, Md.), 2026. https://pubmed.ncbi.nlm.nih.gov/42155597/ * Angiotensin (1-7) and Alamandine: Similarities and differences. Pharmacological research, 2016. https://pubmed.ncbi.nlm.nih.gov/27456244/ * Identification and Characterization of Alamandine-(1-5), a New Component of the Renin-Angiotensin System. Circulation research, 2026. https://pubmed.ncbi.nlm.nih.gov/41221580/ * Alamandine Rescues Cognitive Impairment and Ameliorates Alzheimer's Disease-Like Neuropathology in APP/PS1 Mice. Neurochemical research, 2025. https://pubmed.ncbi.nlm.nih.gov/40853487/ * Phosphoproteomic studies of alamandine signaling in CHO-MrgD and human pancreatic carcinoma cells: An antiproliferative effect is unveiled. Proteomics, 2022. https://pubmed.ncbi.nlm.nih.gov/35652611/