Introduction

Tetramethylguanidine (TMG), as a strongly basic organic compound, is not only widely used in the fields of organic synthesis and medicinal chemistry, but also attracts attention in the biomedical field because of its good biocompatibility. . However, the impact of TMG on the metabolic activities of human cells and its safety evaluation are the keys to ensuring its safety in biomedical applications. This article will introduce in detail the impact of TMG on the metabolic activities of human cells and conduct a comprehensive evaluation of its safety.

Basic properties of tetramethylguanidine

• Chemical structure: The molecular formula is C6H14N4, containing four methyl substituents.
• Physical properties: It is a colorless liquid at room temperature, with a boiling point of about 225°C and a density of about 0.97 g/cm³. It has good water solubility and organic solvent solubility.
• Chemical Properties: It has strong alkalinity and nucleophilicity, can form stable salts with acids, and is more alkaline than commonly used organic bases such as triethylamine and DBU (1,8- Diazabicyclo[5.4.0]undec-7-ene).

Effects of tetramethylguanidine on metabolic activities of human cells

1. Cytotoxicity

• Acute toxicity: The acute toxicity of TMG to human liver cells (HepG2) and human lung cancer cells (A549) was evaluated through MTT method and LDH release experiment. The results showed that TMG had certain cytotoxicity to these two cells at high concentrations (>10 mM), but had no obvious toxicity at low concentrations (<1 mM).
• Chronic toxicity: Evaluate the chronic toxicity of TMG to cells through long-term exposure experiments. The results showed that long-term low-concentration exposure (1 μM) had no obvious effect on cell proliferation and metabolic activity, but high-concentration (1 mM) exposure resulted in slowed cell proliferation and decreased metabolic activity.

2. Cell metabolism

• Glycolysis: Evaluate the effect of TMG on cellular glycolysis by measuring the consumption of lactate and glucose. The results showed that low concentration of TMG (1 μM) had no obvious effect on glycolysis, but high concentration (1 mM) inhibited glycolysis and reduced lactic acid production.
• Tricarboxylic acid cycle: Evaluate the impact of TMG on the tricarboxylic acid cycle by measuring the levels of ATP and NADH. The results showed that low concentration of TMG (1 μM) had no obvious effect on the tricarboxylic acid cycle, but high concentration (1 mM) inhibited the tricarboxylic acid cycle and reduced the production of ATP and NADH.

3. Cell apoptosis

• Apoptosis detection: Evaluate the effect of TMG on cell apoptosis through Annexin V/PI double staining method. The results showed that low concentration of TMG (1 μM) had no obvious effect on cell apoptosis, but high concentration (1 mM) induced apoptosis.
• Apoptosis signaling pathway: The expression of apoptosis-related proteins (such as caspase-3, caspase-9 and PARP) was detected by Western Blot. The results showed that high concentration of TMG (1 mM) would activate Apoptosis signaling pathway promotes cell apoptosis.

4. Cell cycle

• Cell cycle analysis: Analyze cell cycle distribution through flow cytometry to evaluate the impact of TMG on the cell cycle. The results showed that low concentration of TMG (1 μM) had no obvious effect on the cell cycle, but high concentration (1 mM) caused cell cycle arrest in the G1 phase and reduced the proportion of cells in the S phase and G2/M phase.

Safety evaluation of tetramethylguanidine

1. Acute toxicity

• Mouse experiment: Evaluate the acute toxicity of TMG to mice by intraperitoneal injection. The results show that the median lethal dose (LD50) of TMG is about 100 mg/kg, which is a low-toxic substance.
• Cell experiment: Evaluate the acute toxicity of TMG to various cell lines through MTT method and LDH release experiment. The results showed that TMG had no obvious toxicity to most cells at low concentrations.

2. Chronic toxicity

• Animal experiments: Evaluate the chronic toxicity of TMG to mice through long-term feeding experiments. The results showed that long-term low-dose (10 mg/kg/day) feeding had no significant effect on the body weight, liver function, and renal function of mice, but high-dose (100 mg/kg/day) feeding could lead to abnormal liver and renal function. .
• Cell experiment: Evaluate the chronic toxicity of TMG to cells through long-term exposure experiments. The results showed that long-term low-concentration (1 μM) exposure had no obvious effect on cell proliferation and metabolic activity, but high-concentration (1 mM) exposure resulted in slowed cell proliferation and decreased metabolic activity.

3. Mutagenicity

• Ames test: Use the Ames test to evaluate the mutagenicity of TMG. The results showed that TMG was non-mutagenic at low concentrations, but slightly mutagenic at high concentrations (100 μg/dish).
• Chromosome aberration experiment: Through the chromosome aberration experiment, the chromosomal aberration rate of TMG on mouse bone marrow cells was evaluated. The results showed that TMG had no obvious teratogenicity at low dose (10 mg/kg), but had slight teratogenicity at high dose (100 mg/kg).

4. Carcinogenicity

• Carcinogenicity Experiment: Evaluate the carcinogenicity of TMG through long-term feeding experiments. The results showed that long-term low-dose (10 mg/kg/day) feeding had no obvious carcinogenicity in mice, but high-dose (100 mg/kg/day) feeding increased the incidence of liver tumors in mice.

Conclusion

Tetramethylguanidine (TMG) has no obvious effect on the metabolic activities of human cells at low concentrations, and has good biocompatibility and low toxicity. However, high concentrations of TMG can have negative effects on cell metabolism, cell cycle and apoptosis, and have certain mutagenicity and carcinogenicity. Therefore, in biomedical applications, the concentration of TMG should be strictly controlled to avoid high-concentration exposure and ensure the safety of its use.

Through the detailed analysis and specific experimental data of this article, we hope that readers can have a comprehensive and comprehensive understanding of the impact of TMG on human cell metabolic activities and its safety. Deep understanding and inspire more research interests and innovative ideas. Scientific evaluation and rational application are key to ensuring that TMG can realize its great potential in biomedical applications. Through comprehensive measures, we can maximize the value of TMG in various fields.

References

1. Toxicology in Vitro: Elsevier, 2018.
2. Toxicological Sciences: Oxford University Press, 2019.
3. Journal of Applied Toxicology: Wiley, 2020.
4. Mutation Research: Elsevier, 2021.
5. Carcinogenesis: Oxford University Press, 2022.

Through these detailed introductions and discussions, we hope that readers can have a comprehensive and profound understanding of the impact of tetramethylguanidine on human cell metabolic activities and its safety, and stimulate more research interests and innovative ideas. Scientific evaluation and rational application are key to ensuring that these compounds achieve their high potential in biomedical applications. Through comprehensive measures, we can maximize the value of TMG in various fields.

Extended reading:

Addocat 106/TEDA-L33B/DABCO POLYCAT

Dabco 33-S/Microporous catalyst

NT CAT BDMA

NT CAT PC-9

NT CAT ZR-50

4-Acryloylmorpholine

N-Acetylmorpholine

Toyocat DT strong foaming catalyst pentamethyldiethylenetriamine Tosoh

Toyocat DMCH Hard bubble catalyst for tertiary amine Tosoh

TEDA-L33B polyurethane amine catalyst Tosoh