Polyphenols from persimmon fruit attenuate acetaldehyde-induced DNA double-strand breaks by scavenging acetaldehyde

Timing of dietary effects on the epigenome and their potential protective effects against toxins

Exposure to toxins causes lasting damaging effects on the body. Numerous studies in humans and animals suggest that diet has the potential to modify the epigenome and these modifications can be inherited transgenerationally, but few studies investigate how diet can protect against negative effects of toxins. Potential evidence in the primary literature supports that caloric restriction, high-fat diets, high protein-to-carbohydrate ratios, and dietary supplementation protect against environmental toxins and strengthen these effects on their offspring's epigenome. Most notably, the timing when dietary interventions are given - during a parent's early development, pregnancy, and/or lifetime - result in similar transgenerational epigenetic durations. This implies the existence of multiple opportunities to strategically fortify the epigenome. This narrative review explores how to best utilize dietary modifications to modify the epigenome to protect future generations against negative health effects of persistent environmental toxins. Furthermore, by suggesting an ideal diet with specific micronutrients, macronutrients, and food groups, epigenetics can play a key role in the field of preventive medicine. Based on these findings, longitudinal research should be conducted to determine if a high protein, high-fat, and low-carbohydrate diet during a mother's puberty or pregnancy can epigenetically protect against alcohol, tobacco smoke, and air pollution across multiple generations.

ALDH2 plays a role in spermatogenesis and male fertility by regulating oxidative stress in mice

Spermatogenesis and sperm maturation are complex biological processes that involve intricate cellular and molecular interactions. The Aldh2 gene is involved in the metabolism of specific aldehydes generated by oxidative stress. Aldh2 is abundantly expressed in the testis and epididymis; however, the specific role of Aldh2 in regulating spermatogenesis and sperm maturation remains unclear. In the present study, we generated Aldh2 knockout (Aldh2-/-) mice by using CRISPR/Cas9 technology. Aldh2 gene knockout decreased the fertility of male mice. Compared to the control group mice, Aldh2-/- mice showed a significant decrease in the thickness of the seminiferous tubules and the number of germ cells. Further investigation revealed that the meiosis of spermatocytes and acrosome formation in sperm were disrupted in Aldh2-/- mice, leading to oligoasthenoteratozoospermia in male mice. However, the caput epididymis and cauda epididymis in Aldh2-/- mice showed identical proportions of morphologically abnormal sperm. Mechanistically, 4-hydroxynonenal, 3-nitro-L-tyrosine, and malondialdehyde levels were significantly elevated in both the testis and epididymis of Aldh2-/- mice, thus indicating increased oxidative stress in the reproductive system. Collectively, our findings demonstrate that Aldh2 plays a critical role in spermatogenesis by regulating oxidative stress in mice.

The mutagenic properties of formaldehyde and acetaldehyde: Reflections on half a century of progress

Formaldehyde and acetaldehyde are reactive, small compounds that humans are exposed to routinely, variously from endogenous and exogenous sources. Both small aldehydes are classified as human carcinogens. Investigation of the DNA damaging properties of these two compounds began some 50 years ago. In this review, we summarize progress in this field since its inception over half a century ago, distilling insights gained by the collective efforts of many research groups while highlighting areas for future directions. Over the decades, general consensus about aspects of the mutagenicity of formaldehyde and acetaldehyde has been reached. But other characteristics of formaldehyde and acetaldehyde remain incompletely understood and require additional investigation. These include crucial details about the mutational signature(s) induced and possible mechanistic role(s) during carcinogenesis.

Wine, Polyphenols, and the Matrix Effect: Is Alcohol Always the Same?

While the number of publications on wine and health is steadily increasing, ranging from a molecular level to epidemiological studies, often with contradictory results, little attention has been given to a holistic approach to research, starting from the molecular level to arrive at pharmacological and medical conclusions. In this review, some unusual concepts are considered, such as the phytocomplex, the vehicle, and the Matrix effect. The concept of the phytocomplex is discussed, specifically the biological activities of Tyrosol, Hydroxytyrosol, and Resveratrol; indeed, the interactions among different molecules in herbal matrices provide a specific response. This is often markedly different from the response evoked by single constituents in the modulation of microbial populations in the gut, in intestinal stability and bioaccessibility, and, obviously, in inducing biological responses. Among the many alcoholic beverages which contain these molecules, wine has the most peculiar Matrix effect, which can heavily influence the bioavailability of the phytocomplex obtained by the fermentation processes that produce this beverage. Wine's Matrix effect plays an instrumental role in improving the beneficial compounds' bioavailability and/or in inhibiting alcohol metabolites' carcinogenicity. Underestimation of the wine Matrix effect could lead to deceiving results, as in the case of dealcoholized wine or wine-compound-based nutritional supplements; alternatively, this can occur in the emphasis of a single component's toxic activity, in this case, alcohol, ignoring the specific molecular-level protective action of other compounds (polyphenols) that are present in the same matrix. The dark side of the Matrix effect is also discussed. This review confirms the research recommendations made by the WHO Scientific Group, which suggests it is important "to investigate the possible protective effects of ingredients other than alcohol in alcoholic beverages", considering that most recent studies seem not only relevant but also capable of directing future research towards innovative points of view that have so far been too neglected.

Genome analysis of a newly isolated Bacillus velezensis-YW01 for biodegrading acetaldehyde

Acetaldehyde (AL), a primary carcinogen, not only pollutes the environment, but also endangers human health after drinking alcohol. Here a promising bacterial strain was successfully isolated from a white wine cellar pool in the province of Shandong, China, and identified as Bacillus velezensis-YW01 with 16 S rDNA sequence. Using AL as sole carbon source, initial AL of 1 g/L could be completely biodegraded by YW01 within 84 h and the cell-free extracts of YW01 has also been detected to biodegrade the AL, which indicate that YW01 is a high-potential strain for the biodegradation of AL. The optimal culture conditions and the biodegradation of AL of YW01 are at pH 7.0 and 38 °C, respectively. To further analyze the biodegradation mechanism of AL, the whole genome of YW01 was sequenced. Genes ORF1040, ORF1814 and ORF0127 were revealed in KEGG, which encode for acetaldehyde dehydrogenase. Furthermore, ORF0881 and ORF052 encode for ethanol dehydrogenase. This work provides valuable information for exploring metabolic pathway of converting ethanol to AL and subsequently converting AL to carboxylic acid compounds, which opened up potential pathways for the development of microbial catalyst against AL.

Isolation and detection of DNA-protein crosslinks in mammalian cells

DNA-protein crosslinks (DPCs) are toxic DNA lesions wherein a protein is covalently attached to DNA. If not rapidly repaired, DPCs create obstacles that disturb DNA replication, transcription and DNA damage repair, ultimately leading to genome instability. The persistence of DPCs is associated with premature ageing, cancer and neurodegeneration. In mammalian cells, the repair of DPCs mainly relies on the proteolytic activities of SPRTN and the 26S proteasome, complemented by other enzymes including TDP1/2 and the MRN complex, and many of the activities involved are essential, restricting genetic approaches. For many years, the study of DPC repair in mammalian cells was hindered by the lack of standardised assays, most notably assays that reliably quantified the proteins or proteolytic fragments covalently bound to DNA. Recent interest in the field has spurred the development of several biochemical methods for DPC analysis. Here, we critically analyse the latest techniques for DPC isolation and the benefits and drawbacks of each. We aim to assist researchers in selecting the most suitable isolation method for their experimental requirements and questions, and to facilitate the comparison of results across different laboratories using different approaches.

ALDH2 gene rs671 G > a polymorphism and the risk of colorectal cancer: A hospital-based study

BACKGROUND

The susceptibility to some cancers is linked to genetic factors, such as aldehyde dehydrogenase 2 (ALDH2) polymorphisms. The relationship between ALDH2 rs671 and colorectal cancer (CRC) is not clear in Hakka population.

METHODS

Between October 2015 and December 2020, a total of 178 CRC patients and 261 controls were recruited. ALDH2 rs671 was genotyped in these subjects, medical records (smoking history, drinking history and blood cell parameters) were collected, and the relationship between these information and CRC was analyzed.

RESULTS

The proportion of the ALDH2 rs671 G/G, G/A, and A/A genotype was 48.3%, 44.4%, and 7.3% in patients; 62.1%, 34.1%, and 3.8% in controls, respectively. The difference of ALDH2 genotypes distribution between cases and controls was statistically significant (p = 0.011). The higher percentage of smokers and alcoholics, higher level of neutrophil to lymphocyte ratio (NLR), platelet count, and platelet to lymphocyte ratio (PLR), and lower level of lymphocyte count, lymphocyte to monocyte ratio (LMR), and mean hemoglobin concentration were observed in patients. Logistic regression analysis indicated that ALDH2 rs671 G/A genotype (G/A vs. G/G) (adjusted OR 1.801, 95% CI 1.160-2.794, p = 0.009) and A/A genotype (A/A vs. G/G) (adjusted OR 2.630, 95% CI 1.041-6.645, p = 0.041) in the co-dominant model, while G/A + A/A genotypes (G/A + A/A vs. G/G) (adjusted OR 1.883, 95% CI 1.230-2.881, p = 0.004) in the dominant model were risk factors for CRC.

CONCLUSIONS

Individuals carrying ALDH2 rs671 A allele (G/A, A/A genotypes) may be at increased risk of colorectal cancer.

Inhibitory mechanisms of polyphenols on heme protein-mediated lipid oxidation in muscle food: New insights and advances

Lipid oxidation is a major cause of quality deterioration that decreases the shelf-life of muscle-based foods (red meat, poultry, and fish), in which heme proteins, particularly hemoglobin and myoglobin, are the primary pro-oxidants. Due to increasing consumer concerns over synthetic chemicals, extensive research has been carried out on natural antioxidants, especially plant polyphenols. The conventional opinion suggests that polyphenols inhibit lipid oxidation of muscle foods primarily owing to their strong hydrogen-donating and transition metal-chelating activities. Recent developments in analytical techniques (e.g., protein crystallography, nuclear magnetic resonance spectroscopy, fluorescence anisotropy, and molecular docking simulation) allow deeper understanding of the molecular interaction of polyphenols with heme proteins, phospholipid membrane, reactive oxygen species, and reactive carbonyl species; hence, novel hypotheses regarding their antioxidant mechanisms have been formulated. In this review, we summarize five direct and three indirect pathways by which polyphenols inhibit heme protein-mediated lipid oxidation in muscle foods. We also discuss the relation between chemical structures and functions of polyphenols as antioxidants.