0
Article Tier 2 Sign in to save

Nutritional-status dependent effects of microplastics on activity and expression of alkaline phosphatase and alpha-amylase in Brachionus rotundiformis

The Science of The Total Environment 2021 17 citations

AI summary Read the abstract

Microplastic exposure altered alkaline phosphatase and alpha-amylase activity and gene expression in the rotifer Brachionus rotundiformis in ways that depended on nutritional state, with starved and refed animals showing different vulnerability profiles than fed controls, highlighting the importance of host condition in ecotoxicological assessments.

Tissue-nonspecific alkaline phosphatase (ALPL) and alpha-amylase (AMY) are essential in the immune and digestive systems, respectively. Microplastics (MPs) pose a risk to zooplankton which may be in a state of feeding, starvation, or subsequent refeeding. However, molecular characterization of both enzymes and the regulated mechanisms affected by nutritional statuses and MPs remain unclear in zooplankton. In the present study, four full-length genes encoding ALPL and two genes encoding AMY were cloned and characterized from an isolated marine rotifer, Brachionus rotundiformis, including alplA, alplB, alplC, alplD, amy2a, and amy2al. AMY activity and expression of amy2a and amy2al were reduced by starvation and recovered after refeeding compared with feeding. ALPL activity remained unchanged among different statuses, while alplA, alplB and alplD were down-regulated by starvation and refeeding compared with feeding. ALPL activity was not affected by exposure to 10, 100 and 1000 μg/L MPs in rotifers subjected to feeding, starvation and refeeding, whereas AMY activity was significantly enhanced by 1000 μg/L MPs in rotifers subjected to refeeding. Gene expression of the tested genes, except amy2a, was significantly responsive to MPs, especially in the feeding rotifers, depending on MPs concentrations and nutritional statuses. Two-way ANOVA confirmed that these changes were strongly associated with the interaction between MPs concentrations and nutritional statuses. The present study is the first to demonstrate a nutritional status-dependent impact of MPs on immune and digestive responses, and provides more sensitive molecular biomarkers for assessing MPs toxicity using the species as model animals.

More Papers Like This

Article Tier 2

Metabolism deficiency and oxidative stress induced by plastic particles in the rotifer Brachionus plicatilis: Common and distinct phenotypic and transcriptomic responses to nano- and microplastics

AI summary Read the abstract

Researchers found that nanoplastics caused stronger reproductive and population growth inhibition in the marine rotifer Brachionus plicatilis than microplastics, with transcriptomic analysis revealing distinct size-dependent toxicity pathways involving metabolism deficiency and oxidative stress.

Article Tier 2

Influence of polystyrene microplastics on rotifer (Brachionus calyciflorus) growth, reproduction, and antioxidant responses

AI summary Read the abstract

Polystyrene microplastics trigger oxidative stress in the freshwater rotifer Brachionus calyciflorus, increasing reactive oxygen species while impairing growth, reproduction, and the antioxidant enzyme PHGPx in a concentration-dependent manner. These findings demonstrate that microplastics can disrupt the antioxidant defense systems of small aquatic invertebrates, with implications for food web stability in contaminated freshwater ecosystems.

Article Tier 2

Effects of microplastics on reproductive characteristics and mechanisms of the marine rotifer Brachionus plicatilis

AI summary Read the abstract

Researchers exposed marine rotifers (tiny animals at the base of the ocean food chain) to naturally aged microplastics collected from Japanese coastal waters and found reduced reproduction and population growth. The microplastics triggered oxidative stress and suppressed genes involved in reproduction. Since rotifers are food for many fish species, harm to their populations could ripple up through the food chain.

Article Tier 2

Algal density affects the influences of polyethylene microplastics on the freshwater rotifer Brachionus calyciflorus

AI summary Read the abstract

The effects of polyethylene microplastics (10-22 micrometers) on the freshwater rotifer Brachionus were studied at varying algal densities to evaluate how food availability modifies microplastic toxicity. Algal density significantly modulated microplastic impacts on rotifer population growth and reproduction, highlighting the importance of ecological context in microplastic toxicity assessments.

Article Tier 2

Toxic effects of fragmented polyethylene terephthalate particles on the marine rotifer Brachionus koreanus: Based on ingestion and egestion assay, in vivo toxicity test, and multi-omics analysis

AI summary Read the abstract

Scientists tested the effects of fragmented PET microplastics, one of the most common types found in the ocean, on tiny marine organisms called rotifers. While the microplastics did not directly kill the rotifers, they increased oxidative stress and disrupted energy metabolism and immune-related genes. Since rotifers are at the base of the marine food chain, damage to these organisms could have ripple effects that eventually reach humans through seafood.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper