Heavy metals, gastrointestinal polymer-related materials, and gut microbiome in an Indo-Pacific bottlenose dolphin (Tursiops aduncus) recovered from a fisheries bycatch-related event in the East China Sea.

Chapter 8 - Interaction of toxic metals with the gut microbiome

Heavy metal and mineral concentrations and their relationship to histopathological findings in the bowhead whale ( Balaena mysticetus)

Gastrectomy serves as a primary treatment for gastric cancer, a leading global malignancy, and affects significant physiological and anatomical changes in the digestive tract. Recent studies highlight the critical role of gastrointestinal microbiota in postoperative health following digestive tract surgeries, including gastrectomy. These alterations possibly impact the gut microbiota and affect patient health by influencing the bacterial environment in the gastrointestinal tract. However, the relationships between the gastrointestinal tract and the oral, gastric, and gut microbiota after gastrectomy are not clear. In this study, we aimed to characterize alterations in the gut microbiota due to gastrectomy and evaluate whether these alterations are associated with the oral and gastric microbiota. Saliva, gastric fluid, and stool samples were collected from patients diagnosed with primary gastric cancer who underwent gastrectomy at two time points, before and 6 months after gastrectomy. Next, 16S rRNA metagenomic analysis was performed. Diversity and linear discriminant analysis effect size (LEfSe) analyses of each microbiota were conducted before and after gastrectomy to compare alterations in the gut, oral, and gastric microbiota. The diversity of gut microbiota increased after gastrectomy compared to that before gastrectomy (Shannon index, p = 0.044), with LEfSe analysis showing increased abundance of Rothia and Lactobacillus in the gut microbiota. Additionally, the proportion of participants with Rothia in their gut microbiota increased, and this genus was present in the oral and gastric microbiota of almost all participants. Furthermore, a significant rise in Lactobacillus was observed in the gut, oral, and gastric microbiota of paired participants. We characterized gut microbiota alterations caused by gastrectomy and demonstrated their relationship with changes in oral and gastric microbiota, thereby elucidating interactions between the gastrointestinal tract microbiota in response to changes in the gastric environment.

Human exposure to heavy metals, which encompasses both essential and toxic varieties, is widespread. The intestine functions as a critical organ for absorption and metabolism of heavy metals. Gut microbiota plays a crucial role in heavy metal absorption, metabolism, and related processes. Toxic heavy metals (THMs), such as arsenic (As), mercury (Hg), lead (Pb), and cadmium (Cd), can cause damage to multiple organs even at low levels of exposure, and it is crucial to emphasize their potential high toxicity. Nevertheless, certain essential trace elements, including iron (Fe), copper (Cu), and manganese (Mn), play vital roles in the biochemical and physiological functions of organisms at low concentrations but can exert toxic effects on the gut microbiota at higher levels. Some potentially essential micronutrients, such as chromium (Cr), silicon (Si), and nickel (Ni), which were considered to be intermediate in terms of their essentiality and toxicity, had different effects on the gut microbiota and their metabolites. Bidirectional relationships between heavy metals and gut microbiota have been found. Heavy metal exposure disrupts gut microbiota and influences its metabolism and physiological functions, potentially contributing to metabolic and other disorders. Furthermore, gut microbiota influences the absorption and metabolism of heavy metals by serving as a physical barrier against heavy metal absorption and modulating the pH, oxidative balance, and concentrations of detoxification enzymes or proteins involved in heavy metal metabolism. The interactions between heavy metals and gut microbiota might be positive or negative according to different valence states, concentrations, and forms of the same heavy metal. This paper reviews the metabolic interactions of 10 common heavy metals with the gut microbiota and their health implications. This collated information could provide novel insights into the disruption of the intestinal microbiota caused by heavy metals as a potential contributing factor to human diseases.

Gut microbiota: A target for heavy metal toxicity and a probiotic protective strategy

Bacterial community response to chronic heavy metal contamination in marine sediments of the East China Sea

Concerns have been escalating over the increase in heavy metal levels in the envi- ronment due to anthropogenic impacts. Toxic heavy metals (As, Cd, Hg and Pb) are especially dangerous, as they negatively affect organisms and cause outbreaks of diseases. The hare has been proven to be a good indicator of environmental heavy metal contamination. The liver and kidney are the tissues most commonly used in biomonitoring. Hares inhabiting a contaminated habitat have higher concentrations of heavy metals in these tissues than those from a referential habitat. As is mostly accumulated in the nails and hair, Cd in the kidney, Hg in the brain and kidney, and Pb in the brain and diaphragm. Cd and Hg concentrations in hare liver and kidney increased with animal age. In most countries, hare meat is safe for human consumption, while the consumption of entrails is not recommended.

Gut Microbiota and Its Possible Relationship With Obesity

Seaweeds are good bio-monitors of heavy metal pollution and have been included in European coastal monitoring programs. However, data for seaweed species in China are scarce or missing. In this study, we explored the potential of seaweeds as bio-monitor by screening the natural occurring seaweeds in the "Kingdom of seaweed and shellfish" at Dongtou Islands, the East China Sea. Totally, 12 seaweed species were collected from six sites, with richness following the sequence of Rhodophyta > Phaeophyta > Chlorophyta. The concentration of heavy metals (Cu, Cr, Ni, Zn, Pb, Cd, As) in the seaweeds was determined, and the bioaccumulation coefficient was calculated. A combination of four seaweeds, Pachydictyon coriaceum, Gelidium divaricatum, Sargassum thunbergii, and Pterocladiella capillacea, were proposed as bio-monitors due to their high bioaccumulation capabilities of specific heavy metals in the East China Sea and hence hinted the importance of using seaweed community for monitoring of pollution rather than single species. Our results provide first-hand data for the selection of bio-monitor species for heavy metals in the East China Sea and contribute to selection of cosmopolitan bio-monitor communities over geographical large area, which will benefit the establishment of monitoring programs for coastal heavy metal contamination.

Previous studies proved that heavy metals could increase the risk of disease by acting on the gut microbiota. Meanwhile, gut microbiota played important roles in detoxifying heavy metals. However, the response of gut microbiota to heavy metals and which microbes dominated this detoxification processes are still unclear. This study investigated the difference of high-fat-diet (HFD) and normal-diet (ND) gut microbiota and their response to and detoxification effects on arsenic (As), cadmium (Cd), and lead (Pb) exposure. Results showed that gut microbiota of ND and HFD was significantly different and responded to As, Pb, and Cd exposure differently, too. When exposed to 100 ppm As, Cd, or Pb, HFD-fed mice accumulated more heavy metals in the liver and kidney along with more severe functional damage than ND-fed mice, indicated by a more dramatic increase of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities and urinary total protein (TPU), urinary uric acid (UUA), and urinary creatinine (Ucrea) content. Among ND gut microbiota, relative abundance of Bacteroides, Lactobacillus, Butyricimonas, and Dorea was significantly increased by arsenic (As) exposure; relative abundance of Faecoccus and Lactobacillus was significantly increased by Cd exposure; relative abundance of Desulfovibrio, Plasmodium, and Roseburia were significantly increased by Pb exposure. However, among HFD gut microbiota, those microbes were not significantly changed. Bivariate association analysis found weak positive correlations between content of fecal excreted heavy metals and richness of total fecal microbiota as well as abundance of some of the heavy metal-enriched microbes. Our study concluded that HFD increased disease risk of heavy metal exposure probably via its gut microbiota which excreted less heavy metal through feces.

Food contaminants represent food constituents that are accidentally introduced during food preparation cycle. In addition to their direct toxic effects on human health at different levels, they influence both gut microbiota composition and function. This often leads to metabolic disorders linked to many aspects of the human body. Foods are poisoned with physical, chemical, or biological factors either in agriculture or during processing steps. These include naturally occurring compounds such as mycotoxins, agricultural chemicals such as pesticides and antibiotics, persistent organic pollutants, thermal process contaminants (e.g., furans, aromatic compounds, and nitrosamines), or heavy metals. These xenobiotics cause a wide range of toxicities. They also disturb gut homeostasis by inducing intestinal damage and inflammation and gut microbiota dysbiosis. We present herein the first comprehensive review of how food contaminants can specifically influence gut microbiota and intestinal homeostasis, and likewise via gut microbiota-mediated contaminants metabolism. The first part summarizes the different classes of food contaminants and their impact on gut microbiota and its homeostasis, while, the second part discusses the promising role of the gut microbiota in the biodegradation of these xenobiotics and the possible unfortunate exaggerated toxicities in some cases. Finally, we summarize the novel strategies to minimize toxic effects of food contaminants and future directions needed to explore the interactions between food contaminants and the gut microbiota.

Spatial distribution and risk assessment of heavy metal in coastal waters of China.

Inflammatory bowel disease (IBD) is a complex disorder characterized by chronic inflammation of the gastrointestinal tract (GIT). IBD mainly includes two distinct diseases, namely Crohn’s disease and ulcerative colitis. To date, the precise etiology of these conditions is not fully elucidated. Recent research has shed light on the significant role of the oral and gut microbiome in the development and progression of IBD and its collective influence on gut health. This review aims to investigate the connection between the oral and gut microbiome in the context of IBD, exploring the intricate interplay between these microbial communities and their impact on overall gut health. Recent advances in microbiome research have revealed a compelling link between the oral and gut microbiome, highlighting their pivotal role in maintaining overall health. The oral cavity and GIT are two interconnected ecosystems that harbor complex microbial communities implicated in IBD pathogenesis in several ways. Reduction in diversity and abundance of beneficial bacterial species with the colonization of opportunistic pathogens can induce gut inflammation. Some of these pathogens can arise from oral origin, especially in patients with oral diseases such as periodontitis. It is essential to discern the mechanisms of microbial transmission, the impact of oral health on the gut microbiome, and the potential role of dysbiosis in disease development. By elucidating this relationship, we can enhance our understanding of IBD pathogenesis and identify potential therapeutic avenues for managing the disease. Furthermore, innovative strategies for modulating the oral and gut microbiome can promote health and prevent disease occurrence and progression.

Targeting the Gut Microbiota in Coronavirus Disease 2019: Hype or Hope?

Employee is a person who choose to get their income by joining into a system (company) which they trust can guaranty their income and life. In order to get it, they need to work in an organization or company which they like. They have to work with other people in the same group/team. A lot of problem can happen with their work. The writers want to know how satisfied the employee with their job. In case to complete that, the writers do their observation in their restaurant they have internship with, Restaurant Cafe de Veranda. It is located in Amstelveenseweg 764 Amsterdam. It is one of the biggest restaurants in a big city in Holland which is always busy all the time because of its service, location, facilities, and of course the food. This restaurant has more than 40 employees, separated in service, kitchen and dish wash. The writers try to cover all, but in this observation, the writers concentrate in service (the division they work for). Each employee has their own performance in working. And the question is, how satisfied are they with their job? Are they satisfied enough? What make them like to work there? have they already done their best? The writers assume if they are satisfied, they will do their best for the restaurant and it gives impact to their service quality. It can be caused by some factors such as salary, working hours, facilities, working environment, reward (incentive/bonus), or may be human relation (workers and employee or workers and co-workers). The writers analyzed their research by using a qualitative method, by interviewing the employees personally with deep questions, start from the supervisor, assistant supervisor and of course the other employee. The writers are also being helped and supported by the manager of the restaurant, Mr. Remco Dobber. Thank you very much to Mr. Dobber.