In vivo assessment of toxicity and pharmacokinetics of methylglyoxal

A historical perspective on methylglyoxal research is briefly presented, mentioning the documented anticancer and antiviral effects of methylglyoxal. The idea and the supporting experimental evidence of Albert Szent-Gyorgyi et al. that methylglyoxal is a natural growth regulator and can act as an anticancer agent are mentioned. Previously a few in vivo studies suggested safe administration of methylglyoxal. However, recent literature abounds with the toxic effects of methylglyoxal. The authors present a brief critical overview of studies indicating both toxic and beneficial effects of methylglyoxal and suggest that the beneficial effects of methylglyoxal outweigh its toxic effects. Encouraged by the studies of Szent-Gyorgyi et al., the present authors undertook systematic investigations to understand the mechanism of the anticancer effect of methylglyoxal. The results of these investigations led to the proposal that the fundamental changes in malignant cells are critical alterations of glyceraldehyde-3-phosphate dehydrogenase and mitochondrial complex I, and methylglyoxal's anticancer effect might be mediated by acting on these altered sites. Moreover, a new hypothesis on cancer has been proposed, suggesting that excessive ATP formation in cells may lead to malignancy. Toxicity and pharmacokinetic studies were performed on animals and it was observed that methylglyoxal is potentially safe for humans. A methylglyoxal-based anticancer formulation was developed and a three-phase study of treating a total number of 86 cancer patients was carried out. The results appear to be promising. Most of the cancer patients benefited greatly and a significant number of patients became free of the disease. Contrary to the effect of existing anticancer drugs, this methylglyoxal-based formulation is devoid of any toxic effect and reasonably effective against a wide variety of cancers. The symptomatic improvements of the many patients who died of progressive disease suggest that the formulation could also be used for palliation. The authors urge the scientific community to test the formulation and if found effective then to improve it further.

A brief critical overview of the biological effects of methylglyoxal and further evaluation of a methylglyoxal-based anticancer formulation in treating cancer patients.

The plasma fluorescence related to the standard fluorescence of advanced glycation end products (AGEs) is a simple measurable blood parameter for distinct diseases but its importance in human cancer, including non-small cell lung carcinoma (NSCLC), is unknown. Plasma samples of 70 NSCLC patients who underwent resection surgery of the tumor were analyzed for the distinct AGE-related fluorescence at 370 nm excitation/440 nm emission. In a retrospective study, we tested the prognostic relevance of this AGE-related plasma fluorescence. The effect of circulating AGEs on the NSCLC growth was studied experimentally in vitro and in vivo. NSCLC patients with high (> median) AGE-related plasma fluorescence were characterized by a later reoccurrence of the tumor after curative surgery and a higher survival rate compared with patients with low plasma fluorescence (25% versus 47% 5-y survival, P = 0.011). Treating NSCLC cell spheroids with patients’ plasma showed an inverse correlation between the growth of spheroids in vitro and the individual AGE-related fluorescence of each plasma sample. To confirm the impact of circulating AGEs on the NSCLC progression, we studied the NSCLC growth in mice whose circulating AGE level was elevated by AGE-rich diet. In vivo tumorigenicity assays demonstrated that mice with higher levels of circulating AGEs developed smaller tumors than mice with normal AGE levels. The AGE-related plasma fluorescence has prognostic relevance for NSCLC patients in whom the tumor growth-inhibiting effect of circulating AGEs might play a critical role.

Prognostic Potential and Tumor Growth-Inhibiting Effect of Plasma Advanced Glycation End Products in Non-Small Cell Lung Carcinoma

Previous publications from our laboratory have shown that methylglyoxal inhibits mitochondrial respiration of malignant and cardiac cells, but it has no effect on mitochondrial respiration of other normal cells [Biswas, Ray, Misra, Dutta and Ray (1997) Biochem. J. 323, 343-348; Ray, Biswas and Ray (1997) Mol. Cell. Biochem. 171, 95-103]. However, this inhibitory effect of methylglyoxal is not significant in cardiac tissue slices. Moreover, post-mitochondrial supernatant (PMS) of cardiac cells could almost completely protect the mitochondrial respiration against the inhibitory effect of methylglyoxal. A systematic search indicated that creatine present in cardiac cells is responsible for this protective effect. Glutathione has also some protective effect. However, creatine phosphate, creatinine, urea, glutathione disulphide and beta-mercaptoethanol have no protective effect. The inhibitory and protective effects of methylglyoxal and creatine respectively on cardiac mitochondrial respiration were studied with various concentrations of both methylglyoxal and creatine. Interestingly, neither creatine nor glutathione have any protective effect on the inhibition by methylglyoxal on the mitochondrial respiration of Ehrlich ascites carcinoma cells. The creatine and glutathione contents of several PMS, which were tested for the possible protective effect, were measured. The activities of two important enzymes, namely glyoxalase I and creatine kinase, which act upon glutathione plus methylglyoxal and creatine respectively, were also measured in different PMS. Whether mitochondrial creatine kinase had any role in the protective effect of creatine had also been investigated using 1-fluoro-2,4-dinitrobenzene, an inhibitor of creatine kinase. The differential effect of creatine on mitochondria of cardiac and malignant cells has been discussed with reference to the therapeutic potential of methylglyoxal.

Protective effect of creatine against inhibition by methylglyoxal of mitochondrial respiration of cardiac cells.

Use of complementary and alternative therapies is widespread among cancer patients. Throughout the world cancer patients try many questionable or unproven treatment methods. The reasons for adopting these therapies are complex and are related to the social and cultural contexts of their geographical locations. In case of severe illness, the desire to leave no stone unturned is a powerful motivator. In developing countries, ignorance, socioeconomics, and inadequate access to mainstream medical facilities are major factors that play an important role for patients opting for alternative therapies that are replacements for mainstream treatment. Whereas in developed countries a significant proportion of cancer patients try complementary therapies as adjuncts to mainstream care for management of symptoms and to improve quality of life. Many alternative therapies, including pharmacological and biological treatments, remain highly controversial but at the same time are very popular. Evidence from randomized trial supports the value of hypnosis for cancer pain and nausea; relaxation therapy and massage for anxiety; and acupuncture for nausea. This article reviews the different popular alternative cancer therapies practiced in India and neighboring south east Asian countries to project the current international scenario on complementary and alternative cancer therapies.

https://www.oocities.org/sanjoypal/respapers/ccam.pdf

Complementary and alternative cancer therapies: past, present and the future scenario.

Based on our previous in vitro studies with human cells and in vivo studies with animals we had developed an anticancer formulation with methylglyoxal as the lead ingredient. This formation has a tumoricidal effect by inhibiting specifically in cancerous cells, the electron flow and the transfer of reducing equivalent necessary for the production of adenosine-5'-triphosphate (ATP), the cellular energy currency. By keeping this remarkable property in mind, we had treated 24 patients suffering from different types of malignancy (mostly in very advanced stage of the disease) with this methylglyoxal-based formulation. The results indicate a dramatic positive effect on the patients. Out of the 24 patients, 11 are in excellent physical condition, the condition of 5 patients can be considered stable. The rest had either opted out from the treatment or died during the course of study. These results strongly suggest that this formulation is by far more superior than other present forms of treatment against cancer. It is imperative that this formulation be widely used in treating cancer patients, as well as to attempt the improvement of its efficacy.

Implication of the bioelectronic principle in cancer therapy: treatment of cancer patients by methylglyoxal-based formulation

It has been reported earlier that nucleotides, nucleosides and a series of structurally related compounds as well as compounds based on transition state analogy inhibit yeast glyoxalase I. In our study on the metabolic regulation of glyoxalase I, we have found that nucleotides such as ATP, GTP and different classes of other reagents based on transition state analogy (D-isoascorbate, dihydroxyfumaric acid, rhodizonic acid) do not inhibit yeast or goat liver glyoxalase I. The reported inhibition of glyoxalase I by these compounds has been found to be due to the interference of these compounds with the absorbancy at 240 nm of S-D-lactoylglutathione formed by the glyoxalase I reaction.

A reinvestigation of inhibitors of glyoxalase I

Mode of action of Agrobacterium tumefaciens lipopolysaccharide (LPS) in mice hepatic tissue: a comparative study with Salmonella typhimurium LPS.

Lipopolysaccharides ofSalmonella typhimurium inhibit the activity of acetylcholinesterasein vitro in both synaptosomal and erythrocyte membranes. Arrhenius plots show that the transition temperatures of membrane bound acetylcholinesterase are significantly reduced in the presence of lipopolysaccharides, and the activation energies above and below transition temperature have increased with the lowering of transition temperature. These results indicate that an alteration in the fluidity of the phospholipid layer of the membranes, may be responsible for the membrane-specific effect of lipopoly-saccharides on acetylcholinesterase activity.

Study of Salmonella endotoxin on the changes in lipid-protein interactions of membranes using Arrhenius plots of cetylcholinesterase as a tool

Microorganisms require iron for their growth and usually compete with their host for available iron from the system. Iron supplementation to host causes an increase of available iron both to host and to potential microbial invaders and favours the latter more than the former as the bacteria release siderophores which are responsible for iron transport mechanism. In view of this observation a study was done to deal with the distribution of storage and injected iron given as an overload within a physiological pool, taking mice as the host, with a correlation to its utilization byAgrobacterium tumefaciens and with bacterial growth and multiplication. The results obtained help in understanding the host — parasite relationships, regarding bacterial virulence and infection and the growth-promoting effect of iron, as iron promoted the development and progression of serum-exposedA. tumefaciens in mice.

Ray Mk

Papers

Implication of the bioelectronic principle in cancer therapy: treatment of cancer patients by methylglyoxal-based formulation

A reinvestigation of inhibitors of glyoxalase I

Mode of action of Agrobacterium tumefaciens lipopolysaccharide (LPS) in mice hepatic tissue: a comparative study with Salmonella typhimurium LPS.

Study of Salmonella endotoxin on the changes in lipid-protein interactions of membranes using Arrhenius plots of cetylcholinesterase as a tool

Role of iron in the enhancement by Agrobacterium tumefaciens infection in mice.