Phornphan Sornchuer

Kratom (Mitragyna speciosa), a plant native to Southeast Asia, is commonly used as a supplement for fatigue, pain relief, mood enhancement, and euphoria. Kratom extract exhibits diverse pharmacological properties, including antioxidant, anti-inflammatory, and gastrointestinal effects, with studies showing its ability to modulate gut microbiota and stimulate beneficial bacteria growth. Given these properties, kratom treatment may produce significant effects in a rat model, warranting further investigation. Male Wistar rats were administered kratom extract orally on a daily basis for 28 days. Fresh fecal samples were collected and analyzed for changes in gut microbiome composition using 16S rRNA sequencing. Hematological parameters and lipid profiles were also measured to evaluate any systemic effects. The administration of kratom extract did not significantly affect hematological parameters or lipid profiles. However, notable changes were observed in gut microbiota composition, with significant increases in specific bacteria such as Candidatus Stoquefichus and Prevotellaceae UCG-001, and a decrease in Corynebacterium. LEfSe and cladogram analyses corroborated the higher prevalence of Candidatus Stoquefichus, Prevotellaceae UCG-001, and Erysipelatoclostridiaceae in the kratom treatment group compared to controls. Kratom extract significantly alters gut microbiome composition in rats, promoting beneficial bacteria while also elevating certain taxa associated with negative health outcomes. These mixed effects highlight the need for further research on the long-term implications of kratom use for gut health and its broader health consequences, as well as potential therapeutic applications. Not applicable.

Benzo(a)pyrene (B(a)P) and pyrene, the most prominent subtypes of polycyclic aromatic hydrocarbons (PAHs), contaminate environments as organic pollutants. They adversely affect body systems, including degeneration of the central nervous system. This study investigated the in vitro toxic effects of B(a)P and pyrene on proliferation, endoplasmic reticulum (ER) stress induction, and autophagy in human astrocytes using U-87 MG human astrocytoma cells as a model. Both B(a)P and pyrene were toxic to U-87 MG cells in a concentration-dependent manner. Astrocytic proliferation was interfered with, enhancing S-phase cell cycle arrest. B(a)P promoted the presence of autophagic vesicles and the expression of autophagic markers LC3, beclin-1, and p62, suggesting activated autophagy. B(a)P enhanced the expression of ER stress markers BiP, PERK, and IRE1. ER stress appeared to be correlated with autophagy induction, as demonstrated by experiments using chloroquine, an autophagy inhibitor. Pyrene enhanced the expression of autophagic markers and ER stress primarily via PERK activation, although autophagic vesicles were not observed. The study demonstrates that B(a)P enhances ER stress-mediated autophagy more evidently than pyrene and affected toxicity to astrocytes. These results provide a basis for understanding the toxic effects of the main PAH substances affecting astrocytes.

Members of the Bacillus cereus group are spore-forming Gram-positive bacilli that are commonly associated with diarrheal or emetic food poisoning. They are widespread in nature and frequently present in both raw and processed food products. Here, we genetically characterized 24 B. cereus group isolates from foodstuffs. Whole-genome sequencing (WGS) revealed that most of the isolates were closely related to B. cereus sensu stricto (12 isolates), followed by B. pacificus (5 isolates), B. paranthracis (5 isolates), B. tropicus (1 isolate), and “B. bingmayongensis” (1 isolate). The most detected virulence genes were BAS_RS06430, followed by bacillibactin biosynthesis genes (dhbA, dhbB, dhbC, dhbE, and dhbF), genes encoding the three-component non-hemolytic enterotoxin (nheA, nheB, and nheC), a gene encoding an iron-regulated leucine-rich surface protein (ilsA), and a gene encoding a metalloprotease (inhA). Various biofilm-associated genes were found, with high prevalences of tasA and sipW genes (matrix protein-encoding genes); purA, purC, and purL genes (eDNA synthesis genes); lytR and ugd genes (matrix polysaccharide synthesis genes); and abrB, codY, nprR, plcR, sinR, and spo0A genes (biofilm transcription regulator genes). Genes related to fosfomycin and beta-lactam resistance were identified in most of the isolates. We therefore demonstrated that WGS analysis represents a useful tool for rapidly identifying and characterizing B. cereus group strains. Determining the genetic epidemiology, the presence of virulence and antimicrobial resistance genes, and the pathogenic potential of each strain is crucial for improving the risk assessment of foodborne B. cereus group strains.

The Bacillus cereus group, also known as B. cereus sensu lato (B. cereus s.l.), is composed of various Bacillus species, some of which can cause diarrheal or emetic food poisoning. Several emerging highly heat-resistant Bacillus species have been identified, these include B. thermoamylovorans, B. sporothermodurans, and B. cytotoxicus NVH 391-98. Herein, we performed whole genome analysis of two thermotolerant Bacillus sp. isolates, Bacillus sp. B48 and Bacillus sp. B140, from an omelet with acacia leaves and fried rice, respectively. Phylogenomic analysis suggested that Bacillus sp. B48 and Bacillus sp. B140 are closely related to B. cereus and B. thuringiensis, respectively. Whole genome alignment of Bacillus sp. B48, Bacillus sp. B140, mesophilic strain B. cereus ATCC14579, and thermophilic strain B. cytotoxicus NVH 391-98 using the Mauve program revealed the presence of numerous homologous regions including genes responsible for heat shock in the dnaK gene cluster. However, the presence of a DUF4253 domain-containing protein was observed only in the genome of B. cereus ATCC14579 while the intracellular protease PfpI family was present only in the chromosome of B. cytotoxicus NVH 391-98. In addition, prophage Clp protease-like proteins were found in the genomes of both Bacillus sp. B48 and Bacillus sp. B140 but not in the genome of B. cereus ATCC14579. The genomic profiles of Bacillus sp. isolates were identified by using whole genome analysis especially those relating to heat-responsive gene clusters. The findings presented in this study lay the foundations for subsequent studies to reveal further insights into the molecular mechanisms of Bacillus species in terms of heat resistance mechanisms.

Pathanin Chantree, Pongsakorn Martviset, Phornphan Sornchuer, Nattaya Thongsepee, Kant Sangpairoj, Krai Meemon, Nakorn Niamnont, Montakan Tamtin, and Prasert Sobhon. Prev Nutr Food Sci 2023;28:69-78. https://doi.org/10.3746/pnf.2023.28.1.69

Garcinia is a significant medicinal plant with many beneficial phytoconstituents, including garcinol. This study investigated the anti-inflammatory effect of garcinol isolated from Garcinia dulcis fruit in LPS-activated THP-1 and Raw 264.7 macrophages. The results demonstrated that the low concentration of garcinol did not alter cell viability. Furthermore, co-incubation of garcinol with LPS inhibited the production of pro-inflammatory cytokines, including TNF-α, IL-8, IL-6, IL-1β, and pro-inflammatory mediators, including iNOS and COX-2 at the mRNA and protein expression levels. Garcinol also decreased the secretion of TNF-α, IL-6, IL-1β, PGE2, and NO. Moreover, the anti-inflammatory effects involved an alteration in the NF-κB signaling pathway. Downregulation of pIKKα/β, pIκBα, and pNF-κB was observed, hence reducing the translocation of pNF-κB from the cytosol into the nucleus, which subsequently decreased the production of pro-inflammatory molecules. Therefore, garcinol isolated from Garcinia dulcis is a potential candidate as an anti-inflammatory agent for inflammation-related disease treatment.

Garcinia dulcis (GD) extract has been found to have anti-hypertensive properties in animal studies. GD can also alter the colonic microbiota of rats. However, the effects of GD on changes in the gut microbiota and metabolomic profiles of normotensive and hypertensive rats are currently unknown. The purpose of this study was to evaluate changes in the gut microbiota and metabolomic profiles of 2-kidneys-1 clip (2K1C) hypertensive rats after feeding with GD flower extract. Rats were randomly divided into the following 4 groups: sham operation (SO) receiving corn oil (CO) (SO + CO), SO receiving GD (SO + GD), 2K1C receiving corn oil (2K1C + CO) and 2K1C receiving GD (2K1C + GD). Body weight (BW) and systolic blood pressure (SBP) were measured weekly throughout the study. Gut microbiota and fecal metabolites were measured from fresh fecal contents. Alpha diversity results demonstrated a similar microbial richness and diversity between groups. Linear discriminant analysis (LDA) effect size (LEfSe) suggested that GD treatment affected gut microbial community structure in both hypertensive and normotensive rats. Feeding rats with GD caused metabolic alterations that rendered 2K1C + GD rats similar to SO + CO and SO + GD rats. Findings suggest that the impact of GD on gut microbiota and metabolite profiles may be related to its anti-hypertensive properties.

Tanapan Siangcham, Parisa Prathaphan, Jittiporn Ruangtong, Nattaya Thongsepee, Pongsakorn Martviset, Pathanin Chantree, Phornphan Sornchuer, and Kant Sangpairoj. Prev Nutr Food Sci 2022;27:376-83. https://doi.org/10.3746/pnf.2022.27.4.376

Fasciola gigantica, a giant liver fluke, causes tremendous loss to the livestock economy in several regions throughout the world. The situation of drug resistance has been emerging increasingly; therefore, novel drugs and drug targets need to be discovered. The adult F. gigantica inhabits the major bile ducts where bile salts accumulate—these are steroid-like molecules that mediate several physiological processes in organisms through interacting with their specific nuclear receptors. However, the molecular mechanism of the interaction in the parasitic organisms have not been clearly understood. In this study, putative nuclear receptor subfamily 1 of F. gigantica (FgNR1) was identified. Nucleotide and amino acid sequences of the FgNR1 homolog were obtained from the transcriptome of F. gigantica and predicted for properties and functions using bioinformatics. The full-length cDNA was cloned and expressed in the bacterial expression system and then used for immunization. Western analysis and immunolocalization suggested that FgNR1 could be detected in the crude worm antigens and was highly expressed in the caeca and testes of the adult parasite. Moreover, the bile could significantly activate the expression of FgNR1 in cultured parasites. Our results indicated that FgNR1 has high potential for the development of a novel anthelminthic drug in the future.