Impaired regenerative capacity in diabetes mellitus

Under normal conditions, the wound healing process is a flawlessly synchronized biological symphony in which cell migration, proliferative activity, and extracellular matrix (ECM) reorganization follow a strict molecular script. The phased nature of repair is ensured by the precise response of the cells’ receptor apparatus to cascades of inflammatory mediators, growth factors, and cytokines. However, in the presence of prolonged hyperglycemia, characteristic of diabetes mellitus, this harmony is replaced by pathological chaos. Decreased peripheral sensitivity, combined with progressive microangiopathy, creates an environment in which classical regeneration mechanisms are blocked.
A diabetic trophic ulcer is not merely a tissue defect but a state of molecular anabiosis, where the wound “gets stuck” in the chronic inflammation phase. Disruption of local microhemodynamics and systemic metabolic stress lead to wound clearance mechanisms for necrotic debris dominating over synthesis processes. Under such conditions, traditional methods of local therapy often prove ineffective, as they are unable to overcome the profound deficiency of signaling molecules and restore the lost balance between the degradation and formation of matrix structures. This necessitates the introduction of technologies capable of correcting the biochemical profile of damaged tissue at the physicochemical level.
A number of studies have documented a reduction or slowing of growth factor synthesis (9, 10), abnormalities in angiogenesis (9), macrophage function (11), and collagen accumulation, as well as a decline in the epidermal barrier function and the quality of granulation tissue (9) in individuals with diabetes 
Disruption of keratinocyte and fibroblast migration and proliferation processes, a reduction in the number of epidermal nerve fibers (12), slowed bone tissue repair, and an imbalance between the accumulation of ECM components and their remodeling via MMPs (13) have also been noted.
We will examine in detail the processes under normal and pathological conditions to assess the potential of regenerative medicine, drawing on available research sources and clinical cases. 
The Fundamental Stages of Tissue Regeneration Under Normal Biological Conditions
The healing of damaged tissues is a highly complex biological symphony in which each molecular part must be performed at a precisely defined time. This process is not simply the sum of cell divisions—it is a highly coordinated cascade of events aimed at restoring the anatomical integrity and functional capacity of the tissue. Normal repair is based on the dynamic interaction between cell populations, soluble mediators, and components of the extracellular matrix (ECM).
Hemostasis and Inflammation Initiation Phase—The regenerative cycle is initiated at the moment of vascular integrity disruption. Primary hemostasis is ensured by platelet activation, which undergoes degranulation upon contact with subendothelial collagen. Key chemotactic factors, such as platelet-derived growth factor (PDGF) and transforming growth factor beta (TGF-beta), are released from alpha granules. These molecules serve as biochemical signals to attract neutrophils and monocytes to the site of injury. (14) 
At the same time, the arachidonic acid cascade is triggered, leading to the synthesis of prostaglandins and leukotrienes, which modulate vascular permeability. This creates conditions conducive to leukocyte diapedesis. In the first 24–48 hours, neutrophils dominate, acting as the “first line of defense” through mechanisms of phagocytosis and the release of reactive oxygen species (ROS), such as superoxide anion (O2-) and hypochlorite (HOCl), ensuring sterilization of the wound bed
As acute inflammation subsides, macrophages switch their phenotype from pro-inflammatory (M1) to regenerative (M2), initiating the proliferation phase. The key event here is the formation of granulation tissue—a temporary organ of repair. Under the influence of vascular endothelial growth factor (VEGF), new capillaries “sprout” from the remaining vessels (angiogenesis), which is critically important for delivering metabolites and oxygen to the zone of active anabolism. Fibroblasts migrating into the defect zone activate their synthetic function, producing type III collagen, glycosaminoglycans, and fibronectin. Nitric oxide (NO), synthesized by endothelial and inducible NO synthases, acts here as a universal regulator. The chemical reaction converting L-arginine to L-citrulline with the release of NO acts as a catalyst for fibroblast proliferative activity:
L-arginine + O2 + NADPH, followed by the action of NOS, yields L-citrulline + NO + NADP
Adquate levels of NO promote vasodilation and stimulate the synthesis of matrix proteins, laying the groundwork for future tissue formation.
Epithelialization is the final stage in wound healing, requiring keratinocytes to migrate in a coordinated manner. The process begins with a profound phenotypic transformation of basal layer cells located at the wound margins. The biochemical trigger for this process is a change in calcium ion (Ca2+) concentration and the release of growth factors—epidermal growth factor (EGF) and keratinocyte growth factor (KGF). To initiate movement, keratinocytes must overcome intercellular adhesion forces. Under the influence of cytokines (IL-1, TNF-alpha), desmosomes and hemidesmosomes dissolve. The key mechanism here is the dynamic transformation of the receptor apparatus: stable alpha6beta4 integrins, which anchor the cell to the basement membrane, are replaced by the migratory forms alpha5beta1 and alpha-vbeta6. These molecular “anchors” provide temporary adhesion to fibronectin bridge proteins, allowing cells to move across the wound surface. The path for the epithelial layer is prepared by matrix metalloproteinase-1 (MMP-1), which functions as a “molecular scalpel,” cleaving type I collagen and removing physical barriers. The process concludes with the phenomenon of contact inhibition: when keratinocytes from opposite edges meet, intercellular connections are restored, initiating vertical differentiation and the regeneration of a fully functional stratum corneum.
Remodeling Phase 
The final stage, lasting from several weeks to a year, is aimed at achieving mechanical tissue strength. The initial loose type III collagen is replaced by the more robust and structured type I collagen. This process is regulated by a delicate balance between matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). Normally, TIMPs block excessive protease activity, preventing uncontrolled matrix degradation. Gradually, the number of blood vessels decreases, the cellular composition stabilizes, and granulation tissue transforms into mature scar tissue or is restored to its native state, completing the repair cycle. Thus, full-scale skin regeneration is possible only when all molecular agents—from primary cytokines to final matrix enzymes—work in concert.
The Pathophysiology of Diabetic Wound Healing
While the normal wound healing process resembles an orderly construction project, in diabetes mellitus (DM) it turns into a protracted conflict in which destructive processes dominate over regenerative ones. The main driver of this pathology is not only hyperglycemia, but also the cascade of metabolic shifts it triggers, which block the natural triggers of regeneration.
A central component of the pathogenesis is the impairment of macrophage functional plasticity. Normally, these cells should undergo a phenotypic transition from the pro-inflammatory M1 type to the regenerative M2 type. In diabetes, the accumulation of advanced glycation end-products (AGEs) through interaction with RAGE receptors traps macrophages in the M1 state. This pathological state is characterized by continuous expression of pro-inflammatory interleukins (IL-1beta, IL-6) and tumor necrosis factor (TNF-alpha). Instead of initiating matrix synthesis, macrophages continue to produce aggressive cytokines, which transforms the wound into a zone of permanent inflammation, preventing the onset of the proliferation phase. Hyperglycemia is one of the causes of impaired immune responses, which significantly increases the risk of secondary infection. As described in an experiment (8), high glucose concentrations in tissues inhibited the proliferation of cultures of human fibroblasts, bovine endothelial cells, and primary mouse skin keratinocytes. As the experiment shows, fibroblasts become insensitive to stimulation by growth factors. Under conditions of glucose excess, human endothelial cells and macrophages, as well as endothelial cells of bovine skin vessels, began to produce greater amounts of MMPs
It is also important to consider the role of matrix metalloproteinases. One of the most striking features of diabetic ulcers is the hyperactivity of matrix metalloproteinases, particularly MMP-9 (gelatinase B). In healthy tissue, the activity of these enzymes is strictly limited by tissue inhibitors (TIMPs). However, in the diabetic microenvironment, this balance shifts toward uncontrolled proteolysis.
Excess MMP-9 leads to premature degradation not only of damaged fibers but also of newly synthesized fibronectin and growth factors. As a result, the “scaffolding” of the extracellular matrix breaks down faster than keratinocytes can attach to it via their integrins. The MMP-9/TIMP-1 ratio in diabetes becomes a marker of “non-healing”: the higher this index, the more severe the stagnation of the wound healing process.
In diabetes mellitus, a phenomenon of local resistance to growth factors is observed. Even in their presence, target cells (fibroblasts and epithelial cells) are unable to adequately interpret the signal. A key role is played here by a deficiency of insulin-like growth factor-1 (IGF-1) and epidermal growth factor (EGF). (15, 16) Receptor glycation and disruption of intracellular signaling pathways (such as the PI3K/Akt cascade) cause cells to lose their ability to undergo chemotaxis and division. Glycation also disrupts the functioning of the autonomic nervous system. Epithelialization is slowed due to the inability of keratinocytes to activate the metalloproteinases necessary for movement at the required site, leading to the formation of undermined, callous ulcer margins lacking contractile dynamics.
Endothelial dysfunction is a critical factor. Hyperglycemia triggers excessive production of superoxide radicals (O2-) by mitochondria, which react with existing nitric oxide to form highly toxic peroxynitrite (ONOO):NO + O₂ → ONOO
This reaction not only damages cell membranes but also creates a “vacuum” of bioavailable NO. The deprivation of nitric oxide in the tissue blocks angiogenesis—without this gas, blood vessels cannot dilate, and vascular endothelial growth factor (VEGF) loses its effectiveness. The tissue ends up in a state of severe hypoxia and energy deprivation, which permanently establishes the wound as chronic.
In diabetes, one of the significant factors is the inhibitory effect of hyperglycemia and protein glycation on reparative processes. Glycation involves the non-enzymatic binding of glucose to proteins via free amino groups. This disrupts their structure and function, leading to the development of microvascular complications of diabetes.
The Role of Gas Ionization Technology (Plasma Health technology is considered as a trimmer agent)
When natural repair mechanisms are blocked by metabolic chaos and ischemia, the therapeutic strategy requires not merely external wound protection, but active replenishment of deficient metabolites. Plasma Health technology is based on the use of a weak corona discharge that generates low-temperature atmospheric plasma directly from the surrounding air. Replacing argon with the atmospheric environment allows the system to act as a “biochemical prosthesis,” temporarily taking over the functions of the body’s suppressed enzymatic and immune systems.
Under physiological conditions, as described above, the first 24–48 hours of the wound healing process are characterized by the dominance of neutrophils. These cells carry out the “respiratory burst” mechanism, generating superoxide anion (O2 -) and hypochlorite (HOCl), which provide primary sterilization and trigger healing signals. In diabetes mellitus, phagocytic activity is sharply suppressed, leaving the wound defenseless against bacterial invasion.
In this pathogenic situation, reactive oxygen and nitrogen species (RONS) generated by the corona discharge act as “external neutrophils.” The plasma torch delivers a stream of metabolites directly to the site of infection, not merely mimicking the immune system’s function, but acting as a supporting mechanism that sustains and restores the normal course of regeneration 
Let’s examine this in more detail: The ozone (O3) formed during the discharge aggressively oxidizes the lipids of pathogen membranes, disrupting the architecture of bacterial communities that are inaccessible to traditional antibiotics. In turn, short-term controlled oxidative stress serves as a signal for resident macrophages to emerge from a state of “diabetic anabiosis,” initiating their transition to the regenerative M2 phenotype.
As previously explained, a deficiency in nitric oxide (NO)—normally synthesized by endothelial (eNOS) and inducible (iNOS) synthases—is a key component of the “molecular cascade” in diabetes. Tissue deprived of NO loses its ability to vasodilate and proliferate. Plasma Health technology bypasses blocked biochemical pathways by directly fixing atmospheric nitrogen: N2 + O2 is converted into the active metabolite 2NO* under the influence of a corona discharge
Penetrating the interstitium, exogenous NO fills the void left by the “universal regulator.” It binds directly to soluble guanylate cyclase (sGC), activating the cascade of cyclic guanosine monophosphate (cGMP) synthesis. This forcibly restores perfusion to the ischemic zone and stimulates neoangiogenesis, restoring the wound’s ability for active nutrition and gas exchange.
In addition to chemical effects, the gas ionization technology (specifically, Plasma Health technology, which acts as a trimmer agent) transmits a weak electrical pulse through specialized nozzles. This effect corrects the transmembrane potential of cells, which is pathologically altered in diabetes. Weak currents stimulate the mitochondrial respiratory chain, increasing intracellular ATP levels. This provides fibroblasts with the energy necessary for tropocollagen synthesis and structural remodeling of the ECM. 
The alternating magnetic field accompanying the electrical discharge exerts a systemic effect on the histophysiology of the damaged area. In cases of diabetic microangiopathy, the magnetic field facilitates the orientation of blood macromolecules, improving its rheological properties and facilitating the passage of red blood cells through narrowed capillaries. In addition, the magnetic component influences the spatial orientation of newly formed collagen fibers, preventing chaotic proliferation of connective tissue and promoting the formation of a functionally complete regenerate.
Thus, the combined effect of the gas ionization technology system (specifically, Plasma Health technology, which acts as a three-dimensional agent) allows not only for the mechanical cleansing of the wound but also for the physiological reprogramming of its microenvironment. By combining the effects of “external neutrophils,” NO replenishment, and electromagnetic stimulation, the technology overcomes repair stagnation and initiates a full healing cycle, previously impossible under conditions of diabetic metabolism.
The pathogenetic advantage of corona discharge technology lies in the ability of its metabolites to penetrate the cytoplasmic membrane and act directly on the organelles responsible for the cell’s energy and synthetic status—the mitochondria and the endoplasmic reticulum (ER).
In diabetes mellitus, there is a profound suppression of autophagy and mitophagy—the natural processes of degrading damaged structures. As a result, tissues become “clogged” with non-functional fibroblasts containing defective mitochondria, which are unable to synthesize collagen but continue to consume resources and maintain oxidative stress
Plasma metabolites trigger the selective removal (“clearance”) of defective mitochondria. Cells that have exhausted their regenerative capacity undergo apoptosis, making room for new populations. There is also a mild effect on the endoplasmic reticulum, which activates the protein folding control system. 
As noted earlier, in diabetes, they are locked in the pro-inflammatory M1 state. Plasma therapy initiates their repolarization to the M2 state (regenerative phenotype) through the modulation of intracellular signaling pathways.
Cleared of metabolic “waste” and supplied with energy (ATP), M2 macrophages begin active secretion of a cascade of growth factors: TGF-beta, PDGF, and VEGF. These molecules trigger a feedback loop:
Growth factors cause surviving fibroblasts to actively synthesize tropocollagen and elastin. The secreted growth factors induce the synthesis of TIMPs (tissue inhibitors of metalloproteinases).
The key problem with diabetic ulcers is an excess of MMP-9, which literally “devours” growth factors and the tissue’s protein matrix, turning the wound into a degrading environment. The imbalance between aggressive proteases and their inhibitors in diabetes leads to any attempts by the body to initiate healing being nipped in the bud.
The mechanism of gas ionization technology (specifically, Plasma Health technology, acting as a trimeric agent) breaks this vicious cycle. Under the influence of growth factors released by “reprogrammed” M2 macrophages, the concentration of TIMP-1 and TIMP-2 in the intercellular space increases. The inhibitors bind to the active site of metalloproteases, blocking their ability to degrade collagen and cytokines.
Thus, instead of chaotic tissue destruction, a phase of controlled remodeling ensues. Stabilization of the extracellular matrix allows keratinocytes (using their integrin system, described in Section 1) to successfully migrate along a sturdy “bridge” of collagen, leading to the final closure of the wound defect and the formation of healthy regenerated tissue.
CONCLUSION
One of the most significant aspects of using low-temperature plasma in the treatment of trophic ulcers is its ability to act as a selective biomodulator. Unlike aggressive chemical antiseptics or systemic antibiotics, which can exhibit cytotoxicity toward viable tissues, ionized gas acts selectively.
The high efficacy of ionized air plasma against pathogenic microflora is due to fundamental differences in the structure of prokaryotic and eukaryotic cells. Plasma metabolites (ozone, atomic oxygen, NO) cause irreversible damage to bacterial cell walls and disrupt the structure of viral capsids. At the same time, human cells, possessing a well-developed antioxidant defense system and a more complex membrane organization, perceive the same effect not as a damaging factor but as a stimulating signal. Thus, Plasma Health technology simultaneously solves two diametrically opposed tasks: sterilization of the wound surface and initiation of the proliferation of the patient’s own cells.
Unlike most devices on the market that use inert gases (such as argon) to generate a plasma arc, the Plasma Health system is based on patented technology that utilizes a weak corona discharge in ambient air. This solution offers a number of critical advantages:
Plasma is generated directly from the surrounding air, allowing for the production of the widest possible spectrum of active forms of oxygen and nitrogen, identical to those produced by the human immune system.
The uniqueness of the device lies in the simultaneous action of plasma metabolites, weak electrical pulses, and an alternating magnetic field. This synergy allows not only for wound disinfection but also for deep micro-electroporation of tissues for transdermal drug delivery.
The absence of thermal damage and strict calibration of discharge power eliminate the risk of burns, which is particularly important in the treatment of ischemic tissues in patients with diabetes.
Important Note: All clinical results and case studies described in this article were obtained using Plasma Health system equipment and protocols. The effectiveness of this technology is confirmed by European Union certification and many years of successful application in podiatry and dermatocosmetology.
Conclusion
In conjunction with therapy and endocrine treatment, the integration of gas ionization technology into treatment algorithms for diabetic foot ulcers allows for the overcoming of key molecular barriers that hinder healing. By replenishing nitric oxide deficiency, “reprogramming” macrophages, and restoring the balance of matrix metalloproteinases, the Plasma Health system returns the chronic wound to its natural repair cycle. This method represents an evolutionary step from passive observation of the wound healing process to active management of tissue biology at the cellular and subcellular levels.

References

1. Зайцева Е.Л., Токмакова А.Ю. Роль факторов роста и цитокинов в репаративных процессах в мягких тканях у больных сахарным диабетом // Сахарный диабет. — 2014. — №1. — С. 57-62.
2. Muller M., Trocme C., Lardy B. et al. Matrix metalloproteinases and diabetic foot ulcers: the ratio of MMP-1 to TIMP-1 is a predictor of wound healing // Diabetic Medicine. — 2008. — Vol. 25, №4. — P. 419-426.
3. Liu Y., Min D., Bolton T. et al. Increased Matrix Metalloproteinase-9 Predicts Poor Wound Healing in Diabetic Foot Ulcers // Diabetes Care. — 2009. — Vol. 32, №1. — P. 117-119.
4. Fridman G., Friedman G., Gutsol A. et al. Applied Plasma Medicine // Plasma Processes and Polymers. — 2008. — Vol. 5, №6. — P. 503-533.
5. Brem H., Tomic-Canic M. Cellular and molecular basis of wound healing in diabetes // The Journal of Clinical Investigation. — 2007. — Vol. 117, №5. — P. 1219-1222.
6. Bamberger C., Schärer A., Antsiferova M. et al. Activin Controls Skin Morphogenesis and Wound Repair Predominantly via Stromal Cells // The American Journal of Pathology. — 2005. — Vol. 167, №3. — P. 733-747.
7. Технические материалы и протоколы системы Plasma Health®. Внутренняя документация и отчеты о клиническом применении. — 2017-2026.
8. Blakytny R, Jude E. The molecular biology of chronic wounds and delayed healing in diabetes. Diabetic Medicine. 2006;23(6):594–608.
9. Falanga V. Wound healing and its impairment in the diabetic foot. The Lancet. 2005;366(9498):1736–1743. DOI: http://dx.doi.org/10.1016/S0140-6736(05)67700-8 
10. Galkowska H, Wojewodzka U, Olszewski WL. Chemokines, cytokines, and growth factors in keratinocytes and dermal endothelial cells in the margin of chronic diabetic foot ulcers. Wound Repair and Regeneration. 2006;14(5):558–565. DOI: http://dx.doi.org/10.1111/j.1743-6109.2006.00155.x
11. Fukumura D, Gohongi T, Kadambi A, Izumi Y, Ang J, Yun C-O, et al. Predominant role of endothelial nitric oxide synthase in vascular endothelial growth factor-induced angiogenesis and vascular permeability. Proceedings of the National Academy of Sciences. 2001;98(5):2604–2609. DOI: http://dx.doi.org/10.1073/pnas.041359198
12. Maruyama K, Asai J, Ii M, Thorne T, Losordo DW, D’Amore PA. Decreased Macrophage Number and Activation Lead to Reduced Lymphatic Vessel Formation and Contribute to Impaired Diabetic Wound Healing. The American journal of pathology. 2007;170(4):1178–1191. DOI: http://dx.doi.org/10.2353/ajpath.2007.060018 
13. Gibran NS, Jang Y-C, Isik FF, Greenhalgh DG, Muffley LA, Underwood RA, et al. Diminished Neuropeptide Levels Contribute to the Impaired Cutaneous Healing Response Associated with Diabetes Mellitus. The Journal of surgical research. 2002;108(1):122–128. DOI: http://dx.doi.org/10.1006/jsre.2002.6525 
14. Jude EB, Blakytny R, Bulmer J, Boulton AJM, Ferguson MWJ. Transforming growth factor-beta 1, 2, 3 and receptor type I and II in diabetic foot ulcers. Diabetic Medicine. 2002;19(6):440–447. DOI: http://dx.doi.org/10.1046/j.1464-5491.2002.00692.x 
15. 14. Moulin V. Growth factors in skin wound healing. European Journal of Cell Biology. 1995;68(1):1–7.
16. Mutsaers SE, Bishop JE, McGrouther G, Laurent GJ. Mechanisms of tissue repair: from wound healing to fibrosis. The International Journal of Biochemistry & Cell Biology. 1997;29(1):5–17. DOI: http://dx.doi.org/10.1016/S1357-2725(96)00115-X