Methylene Blue's Potential to Prevent Aging

 

 As the first fully manufactured drug, methylene blue (MB) has a variety of clinical uses.
The anti-oxidative effects of MB, in addition to its well-known uses in surgical staining, malaria, and methemoglobinemia, have recently rekindled interest in this century-old medication.
Systematic aging, which affects many different organs, including the brain and skin, has been linked to mitochondrial malfunction.
Under age-related circumstances, this causes an increase in oxidative stress and downstream phenotypes.
Bypassing Complex I/III action in the mitochondria, MB can somewhat reduce oxidative stress.
Additionally, MB has broad spectrum UV absorption abilities. 

1. Initialization

A well-known medication, methylene blue (MB), was first created as a textile dye in 1876 .
Because of its low molecular weight, MB can reach tissues quickly.
Leucomethylene blue (leucoMB) can be created from MB through reduction, making it possible to use it as an antioxidant (Figure 1A) .
The use of MB, an FDA-approved medication, has been widespread in the treatment of methemoglobinemia, malaria, and other conditions . 

The "free radicals theory of aging" contends that the assaults of free radicals are what cause cell and tissue aging .
Reactive oxygen species (ROS) are primarily formed in mitochondria in human cells , and as people age, different tissues show reductions in mitochondrial mass, respiration capacity, and efficiency .
Dysfunctional mitochondria result in lower ATP and higher ROS production , which worsens mitochondrial damage.
This vicious loop speeds up cellular aging and causes severe cellular damage.
A strong contender for an anti-aging medication, MB's antioxidative abilities primarily enhance mitochondrial activity and disrupt the ROS-mitochondrial damage cycle . 

MB is a derivative of the phenothiazine that can be converted into leucoMB (Figure 1A).
LeucoMB is white but MB solution is blue when it is oxidized .
MB is extremely permeable across biomembranes because it is hydrophilic and lipophilic.
MB has a positive charge as well .
The redox potential of MB is 11 mV, and because to its low redox potential, it may easily cycle between its oxidized and reduced forms in mitochondria .
These qualities enable MB to function in mitochondria as a catalytic redox cycler, enhancing cytochrome oxidase activity and ATP synthesis (Figure 1). Bypassing Complex I/III activity, MB also reduces the generation of ROS .
Through Complex I, MB absorbs electrons from NADH and transforms into leucoMB.
These electrons can be transferred immediately from leucoMB to cytochrome c, where they are reoxidized to MB.
Therefore, under pathological circumstances, MB may be able to shield cells from oxidative damage. 

 Figure 1 shows the composition and operation of MB.
(A) LeucoMB is a reduced version of the phenothiazine derivative MB.
(B) The synthesis of ATP and ROS is related to the mitochondrial electron transport chain (ETC).
(Figure derived from "Electron Transport Chain," by BioRender, 10 October 2021, downloaded from https://app.biorender.com/biorender-templates/t-5edadc578a691400acf3c4ec-electron-transport-chain.) MB can function as a catalytic redox cycler in mitochondria and bypass Complex I/III activity. 

 

2. Methylene Blue's Anti-Aging Potential

MB in Brain Aging (2.1)

 

The blood-brain barrier (BBB) can be successfully crossed by MB because it is extremely lipophilic .
After oral administration or intravenous injection in rats, MB concentration is discovered to be higher in the brain than in plasma .
Additionally, it strongly binds to mitochondria .
Instead of scavenging free radicals like other antioxidants like MitoQ and MitoVitE do, MB bypasses Complex I/III activity to lower the formation of free radicals .
In fact, MB can partially restore the membrane potential in Complex III-inhibited mitochondria in both mice and rats . As an electron donor, MB can also boost brain cytochrome oxidase expression and oxygen consumption in vivo .
Nitric oxide (NO), which reduces the activity of cytochrome c oxidase, was also demonstrated to be efficiently inhibited by modest dosages of MB .
All of these characteristics make MB a prospective therapeutic candidate for the treatment of brain disorders. 

Numerous studies have suggested a connection between mitochondrial malfunction and aberrant A and tau processing .
The activity of the mitochondria can be hampered if the amyloid precursor protein (APP) becomes stuck in the membrane.
By lowering ATP generation and raising oxidative stress, tau overexpression can also lead to mitochondrial malfunction .
On the other hand, impaired mitochondrial function can lead to inappropriate A synthesis and tau phosphorylation.
According to reports, MB can either dissolve already-formed A- and tau aggregates by autophagic clearance or stop them from forming in the first place . MB may either directly or indirectly target the cleavage of APP by -secretase and control the production of A .
The ability of MB to reduce A and tau aggregation may help treat Alzheimer's disease (AD) through enhancing mitochondrial activities in affected neurons.
Additionally, it has been demonstrated that cytochrome oxidase activity decreases in AD , but MB can boost the enzymatic activity of cytochrome oxidase, increasing the oxidative metabolic capacity of neurons. 

Another age-related neurodegenerative illness is Parkinson's Disease (PD).
One of the most prevalent movement disorders with dopaminergic neuronal loss is it .
Lewy Bodies and Lewy Neurites, intracellular aggregates of the protein -synuclein (-syn), are the pathological characteristic of Parkinson's disease (PD) .
When A-syn is translocated to the mitochondria, it can cause progressive mitochondrial dysfunction .
Through the induction of oxidative stress in PD, mitochondrial dysfunction is thought to be the main factor causing dopaminergic apoptosis .
Considering that MB enhances mitochondrial activity, it might be a potential PD therapy. 

MB is a promising memory booster in addition to helping age-related brain problems.
Since mitochondrial dysfunction builds up with time and metabolic dysregulation is shown in aging brains, enhancing mitochondria may help neurons keep their health and perform better. 

 

MB in Skin Aging (2.2)

 Both intrinsic and extrinsic skin aging entail oxidative damage .
Accelerated aging is caused by increased oxidative damage, which reduces collagen synthesis and increases collagen breakdown, especially in skin exposed to specific environmental risk factors like UV radiation.
Antioxidants like MB may shield skin and delay the effects of aging (Figure 2). 

 Figure 2 shows how MB has a positive impact on human skin.
ROS buildup on skin is a result of environmental variables, particularly UV radiation, which damages DNA, impairs ETC, reduces collagen synthesis, and increases collagen breakdown.
As an effective antioxidant, MB can stop ROS from causing accelerated aging and can also present it.
Additionally, MB can encourage the multiplication of fibroblasts, aiding in the speedy healing of wounds.
Additionally, MB is a chemical UV blocker with a broad spectrum (Figure created with BioRender.com, 10 October 2021).
Together, MB provides the human skin with three levels of protection, including UV irradiation blocking, cellular oxidative damage mitigation, skin proliferation stimulation, and wound healing stimulation. 

An earlier investigation found that MB therapy in healthy fibroblasts could prolong life and promote cell growth while lowering aging markers .
According to that study, MB reversed premature senescence brought on by H2O2 or cadmium, raised cytochrome oxidase by 30%, increased oxygen consumption by 37–70%, and the ratio of MB/cytochrome c may be crucial for MB's protective action.
Intriguingly, MB-treated skin cells outperformed both of them significantly in terms of increasing cell proliferation and lowering age-related indicators when compared to typical antioxidants used in cosmetics, including vitamin C and retinol (vitamin A) . MB therapy in skin fibroblasts could increase the expression of ECM proteins, including upregulation of elastin and collagen 2A1, the two essential proteins for healthy, youthful skin. This is in addition to its powerful antioxidant effect.
A different investigation revealed that MB offers broad-spectrum UV ray absorption and reduces DNA double-strand breaks brought on by UVB irradiation in human keratinocytes .
All of the evidence points to MB as protective and advantageous for human skin, which implies that incorporating MB into daily skincare may successfully prevent photoaging. 

MB can speed up the healing of wounds.
The ECM's collagen and elastin disintegrate as we age, and fibroblast migration and proliferation frequently decrease .
Therefore, structural and functional changes cause the skin's ability to mend itself to deteriorate.
According to our research, MB therapy may encourage fibroblast migration and proliferation during the healing of wounds .
In rat skin survival burn models, MB therapy could slow the progression of necrosis, which may be mediated by lowering oxidative stress by preventing nitric oxide (NO) production .
Additionally, MB can speed up wound healing by lessening the burden of antimicrobials and hypergranulation.
Without endangering healthy cells, MB also has a drying effect .
Overall, it has been demonstrated in laboratory models that MB increases tissue vitality with minimal to no discomfort. 

 

MB in Progeria (2.3)

A C to T de novo point mutation on exon 11 of the LMNA gene causes Hutchinson-Gilford Progeria Syndrome (HGPS), a hereditary condition that causes rapid aging . MB has demonstrated potential for treating HGPS.
Lamin A, which contains a cryptic splice site that results in a 50 amino acid loss of the protein, is replaced by progerin as a result of the mutation .
Progerin becomes an aberrant form of pre-Lamin A with a persistent farnesyl modification as a result of the deletion, which eliminates a crucial protease cleavage site.
Progerin then becomes fixed in the nuclear membrane and is localized to the nuclear envelope . A rapid aging phenotype in patients is the result of progerin's disruption of the nuclear skeleton, which also causes nuclear abnormalities, nuclear envelope blebbing, transcriptional alterations, and severe cellular stress .
Elevated levels of mitochondrial-specific superoxide (MitoSOX), ROS, and inhibition of the mitochondrial biosynthesis gene PGC-1 are signs of mitochondrial malfunction in both HGPS cells and animal models . 

MB has shown that it can reverse HGPS characteristics as a highly permeable molecule and mitochondrial antioxidant .
In addition to reducing mitochondrial abnormalities, our team discovered that MB therapy also restored the transcriptional alterations in HGPS.
Additionally, MB exhibits the capacity to solubilize progerin in the nuclear envelope, rectifying blebbed nuclei in HGPS cells and significantly lowering cellular stress.
It is still unknown whether these benefits are connected to MB's antioxidant property, and more investigation is being conducted.