Protective Effects of Pyruvic Acid Salt Against Lithium Toxicity and Oxidative Damage in Human Blood Mononuclear Cells

The Production of Pyruvate in Biological Technology: A Critical Review

Pyruvic acid has numerous applications in the food, chemical, and pharmaceutical industries. The high costs of chemical synthesis have prevented the extensive use of pyruvate for many applications. Metabolic engineering and traditional strategies for mutation and selection have been applied to microorganisms to enhance their ability to produce pyruvate. In the past decades, different microbial strains were generated to enhance their pyruvate production capability. In addition to the development of genetic engineering and metabolic engineering in recent years, the metabolic transformation of wild-type yeast, E. coli, and so on to produce high-yielding pyruvate strains has become a hot spot. The strategy and the understanding of the central metabolism directly related to pyruvate production could provide valuable information for improvements in fermentation products. One of the goals of this review was to collect information regarding metabolically engineered strains and the microbial fermentation processes used to produce pyruvate in high yield and productivity.

Engineering of Yarrowia lipolytica for producing pyruvate from glycerol

The present study aims to increase pyruvate production by engineering Yarrowia lipolytica through modifying the glycerol metabolic pathway. Results: Wild-type Yarrowia lipolytica (Po1d) was engineered to produce six different strains, namely ZS099 (by over-expressing PYK1), ZS100 (by deleting DGA2), ZS101 (by over-expressing DAK1, DAK2, and GCY1), ZS102 (by over-expressing GUT1 and GUT2), ZS103 (by over-expressing GUT1) and ZSGP (by over-expressing POS5 and deleting GPD2). Production of pyruvate from engineered and control strains was determined using high-performance liquid chromatography (HPLC). Subsequently, the fermentation conditions for producing pyruvate were optimized, including the amount of initial inoculation, the addition of calcium carbonate (CaCO₃), thiamine and glycerol. Finally, for scaled-up purposes, a 20-L fermentor was used. It was observed that pyruvate production increased by 136% (8.55 g/L) in ZSGP strain compared to control (3.62 g/L). Furthermore, pyruvate production by ZSGP reached up to 110.4 g/L in 96 h in the scaled-up process. We conclude that ZSGP strain of Y. lipolytica can be effectively used for pyruvate production at the industrial level.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03158-7.

Cell-Free Biosynthesis System: Methodology and Perspective of in Vitro Efficient Platform for Pyruvate Biosynthesis and Transformation

The modification of intracellular metabolic pathways by metabolic engineering has generated many engineered strains with relatively high yields of various target products in the past few decades. However, the unpredictable accumulation of toxic products, the cell membrane barrier, and competition between the carbon flux of cell growth and product synthesis have severely retarded progress toward the industrial-scale production of many essential chemicals. On the basis of an in-depth understanding of intracellular metabolic pathways, scientists intend to explore more sustainable methods and construct a cell-free biosynthesis system in vitro. In this review, the synthesis and application of pyruvate as a platform compound is used as an example to introduce cell-free biosynthesis systems. We systematically summarize a proposed methodology workflow of cell-free biosynthesis systems, including pathway design, enzyme mining, enzyme modification, multienzyme assembly, and pathway optimization. Some new methods, such as machine learning, are also mentioned in this review.

[Lithium in the psychopharmacology of affective disorders and mechanisms of its effects on cellular physiology]

However, despite successful use of lithium in the treatment of affective disorders for almost 40 years, the mechanisms of its therapeutic action are still poorly understood. This review presents and summarizes the current literature about the use of lithium in treatment of affective disorders, as well as its effects on cellular physiology, with a separate description of the effect of this ion on the functioning of nerve tissue and ion-molecular mechanisms.

[Lithium ascorbate as a cerebroprotective agent in a model of ischemic stroke]

INTRODUCTION

Ischemic stroke is one of the most severe neurological pathologies with high mortality and disability. In this connection, the development and study of new drugs for the prevention and treatment of stroke is an extremely important task. A new approach to neuroprotection is the use of lithium salts with antioxidant activity.

AIM

To study the cerebroprotective effect of lithium ascorbate on a rat model of ischemic stroke.

MATERIAL AND METHODS

Test samples of lithium ascorbate were synthesized ex tempore for an experiment using reagents of ACS qualification (Sigma-Aldrich). The ischemic stroke model was realized using the filament occlusion of the middle cerebral artery in rats of the Sprague Dawley line according to standardized procedure. Neurological examination of the animals, histological study of brain tissue with staining of brain sections, and calculating the volume of cerebral infarction were performed.

RESULTS AND CONCLUSION

There is a significant cerebroprotective effect of lithium ascorbate expressed in a multiple decrease in the volume of the zone of cerebral infarction (by 75% of the control group indicator) and the absence of mortality in the experimental group of animals. Newly discovered distinct anti-stroke effect of lithium ascorbate in combination with low toxicity could be considered promising for further clinical studies and practical application in neurology.

The Effect of Organic Lithium Salts on Plasma 8-Hydroxy-2'-Deoxyguanosine in Bipolar Patients In Vitro

Objective

An important step in the development of new drugs for the treatment of bipolar disorder (BD) is the study of the extent to which novel lithium salts whose anionic component has an antioxidant effect can reduce oxidative DNA damage in human blood plasma in vitro. We investigated the effects of lithium salts containing different organic anionic components (lithium carbonate (Li-CAR), pyruvate (Li-PYR), succinate (Li-SUC), fumarate (Li-FUM) and ascorbate (Li-ASC)) on levels of the oxidative damage product of DNA-8-hydroxy-2'-deoxyguanosine (8-OH-dG) in blood plasma after incubation of blood samples from healthy individuals (healthy group) and patients with bipolar disorder (BD-group) with these chemical compounds.

Methods

Blood incubation was carried out in the presence of lithium salts (1.2 mM) for 1 hour at 37°C. Measurement of 8-OH-dG concentrations in blood plasma was carried out by enzyme immunoassay using a DNA Damage Competitive Elisa Kit (Thermo Fisher Scientific, USA).

Results

In samples without compounds (control), concentrations of 8-OH-dG in the BD-group did not differ from the group of healthy individuals. None of the tested compounds had a significant effect on 8-OH-dG in healthy individuals. In BD patients, Li-PYR significantly reduced levels of plasma 8-OH-dG, while other compounds did not have a noticeable effect.

Conclusion

Lithium pyruvate reduces oxidative DNA damage in the blood of BD patients in vitro, demonstrating the potential of this compound to function not only as a mood stabilizer, but also as an antioxidant and cytoprotector.

Cross-Talk between Mitochondrial Dysfunction-Provoked Oxidative Stress and Aberrant Noncoding RNA Expression in the Pathogenesis and Pathophysiology of SLE

Systemic lupus erythematosus (SLE) is a prototype of systemic autoimmune disease involving almost every organ. Polygenic predisposition and complicated epigenetic regulations are the upstream factors to elicit its development. Mitochondrial dysfunction-provoked oxidative stress may also play a crucial role in it. Classical epigenetic regulations of gene expression may include DNA methylation/acetylation and histone modification. Recent investigations have revealed that intracellular and extracellular (exosomal) noncoding RNAs (ncRNAs), including microRNAs (miRs), and long noncoding RNAs (lncRNAs), are the key molecules for post-transcriptional regulation of messenger (m)RNA expression. Oxidative and nitrosative stresses originating from mitochondrial dysfunctions could become the pathological biosignatures for increased cell apoptosis/necrosis, nonhyperglycemic metabolic syndrome, multiple neoantigen formation, and immune dysregulation in patients with SLE. Recently, many authors noted that the cross-talk between oxidative stress and ncRNAs can trigger and perpetuate autoimmune reactions in patients with SLE. Intracellular interactions between miR and lncRNAs as well as extracellular exosomal ncRNA communication to and fro between remote cells/tissues via plasma or other body fluids also occur in the body. The urinary exosomal ncRNAs can now represent biosignatures for lupus nephritis. Herein, we’ll briefly review and discuss the cross-talk between excessive oxidative/nitrosative stress induced by mitochondrial dysfunction in tissues/cells and ncRNAs, as well as the prospect of antioxidant therapy in patients with SLE.