Summary of recent experimental animal and cell studies linking MNPs to metabolic dysfunction and obesity.
| Year | Study | Model | Exposure | Main findings |
|---|---|---|---|---|
| 2022 | Zhao et al. “Polystyrene bead ingestion promotes adiposity and cardiometabolic disease in mice.” [16] | Mice | Polystyrene (PS) beads 0.5 and 5 µm in drinking water for 12 weeks | Accelerated weight gain, increased body fat, hyperglycemia, insulin resistance markers, gut microbiome changes consistent with obesity, and adipogenic gene-expression changes in perivascular adipose tissue. |
| 2022 | Shiu et al. “Dietary exposure to polystyrene nanoplastics impairs fasting-induced lipolysis in adipose tissue from high-fat diet fed mice.” [17] | High-fat diet (HFD) mice; adipocytes in vitro/ex vivo | 60 nm PS nanoplastics | Nanoplastics accumulated in white adipose tissue, reduced beta-adrenergic lipolysis, impaired fasting lipid mobilization, enlarged subcutaneous adipocytes, and increased liver lipid accumulation. |
| 2022 | Huang et al. “Polystyrene microplastic exposure induces insulin resistance in mice via dysbacteriosis and pro-inflammation.” [18] | Mice on normal chow and HFD | PS microplastics (MPs) | Induced insulin resistance and aggravated HFD-induced insulin resistance; associated with gut dysbiosis, inflammation, tissue accumulation, and impaired hepatic insulin signaling. |
| 2023 | Okamura et al. “Oral Exposure to Polystyrene Microplastics of Mice on a Normal or High-Fat Diet and Intestinal and Metabolic Outcomes.” [14] | Mice | Oral PS MPs | MPs with HFD induced metabolic disturbances, such as diabetes and non-alcoholic fatty liver disease (NAFLD). |
| 2023 | Huang et al. “Polystyrene microplastics trigger adiposity in mice by remodeling gut microbiota and boosting fatty acid synthesis.” [19] | Mice | PS MPs | Low/intermediate exposure caused overweight/adiposity, increased appetite, lower activity, altered cecal microbiota, and increased hepatic fatty-acid synthesis; high concentrations caused weight loss, showing non-monotonic effects. |
| 2023 | Du et al. “Combined effects of high-fat diet and polystyrene microplastic exposure on microplastic bioaccumulation and lipid metabolism in zebrafish.” [20] | Zebrafish | 50 µm PS MPs | HFD increased PS accumulation; PS exposure aggravated hepatic lipid accumulation and liver injury and disrupted lipid/energy metabolism genes. |
| 2024 | Zhang et al. “Polystyrene nanoplastics inhibit beige fat function and exacerbate metabolic disorder in high-fat diet-fed mice.” [21] | HFD mice + primary beige adipocytes | PS nanoplastics | Impaired beige adipocyte thermogenic function and worsened systemic metabolic performance in HFD mice. |
| 2024 | Zhai et al. “Long-Term Exposure to Polystyrene Microspheres and High-Fat Diet-Induced Obesity in Mice: Evaluating a Role for Microbiota Dysbiosis.” [22] | HFD mice | Long-term PS microspheres | Reported greater body weight, liver weight, adipose tissue, and serum lipids in HFD mice exposed to PS; evaluated microbiota dysbiosis as a mechanism. |
| 2024 | Zhao et al. “Obesogenic polystyrene microplastic exposures disrupt the gut-liver-adipose axis.” [9] | Mice | 0.5 and 5 µm PS beads in water for 13 weeks | Confirmed potentiated weight gain and adipose expansion; found adipose macrophage changes, altered bile acids, hepatic cholesterol, and nuclear receptor signaling. |
| 2024 | Moon et al. “Microplastic exposure linked to accelerated aging and impaired adipogenesis in fat cells.” [23] | Mice + Human adipose-derived stem cells (hASC) | Oral PS MPs in mice; in vitro hASC exposure | MPs accumulated in mouse white adipose tissue and induced adipose senescence/inflammation; in human adipose-derived cells, MPs impaired adipogenic differentiation. |
| 2024 | Xu et al. “Impact of Microplastic Exposure on Blood Glucose Levels and Gut Microbiota: Differential Effects under Normal or High-Fat Diet Conditions.” [24] | Mice, normal vs. HFD | PS MPs | MP exposure worsened blood-glucose disruption under HFD conditions and altered gut microbiota; less effect under normal diet. |
| 2025 | Kim et al. “Mixtures of polystyrene micro and nanoplastics affects fat and glucose metabolism in 3T3-L1 adipocytes and zebrafish larvae.” [25] | 3T3-L1 adipocytes + HFD zebrafish larvae | Mixed PS micro/nanoplastics | Increased adipogenesis/lipogenesis markers, reduced glucose uptake and insulin signaling in adipocytes; zebrafish showed increased body weight and blood glucose. |
| 2025 | Jhang et al. “Impact of polyethylene terephthalate and polylactic acid nanoplastics on cellular uptake and lipid metabolism in differentiated 3T3-L1 adipocytes.” [26] | 3T3-L1 adipocytes | PET and PLA nanoplastics | PET nanoplastics entered adipocytes and altered lipid handling via AMPK/HSL-mediated lipolysis; PLA did not show the same effect. |
| 2025 | Kou et al. “Polystyrene microplastics impair brown and beige adipocyte function via the gut microbiota-adipose tissue crosstalk in high-fat diet mice.” [27] | HFD mice | PS MPs | Reduced energy expenditure, increased lipid accumulation, impaired BAT/iWAT thermogenesis, worsened gut dysbiosis; microbiota transplantation reproduced lipid/thermogenic effects. |
| 2025 | Shen et al. “Exposure to Nanoplastics During Pregnancy Induces Brown Adipose Tissue Whitening in Male Offspring.” [28] | Pregnant mice and offspring | Gestational PS nanoplastics | Male offspring developed beige adipose tissue whitening, larger white adipocytes, increased lipogenesis, and inhibited lipophagy. |
| 2025 | Hsu et al. “Polystyrene nanoplastics disrupt the intestinal microenvironment by altering bacteria-host interactions through extracellular vesicle-delivered microRNAs.” [29] | Mice, enterocyte model | 100 nm PS nanoplastics orally for 12 weeks | Increased body-weight gain without significant liver weight change; showed intestinal barrier and microbiota mechanisms. |
| 2025 | Han et al. “Chronic Nanoplastic Exposure Promotes the Development and Progression of Metabolic Dysfunction-Associated Steatotic Liver Disease.” [30] | Animal liver/metabolic disease model | Nanoplastics | Chronic NP exposure promoted metabolic dysfunction-associated steatotic liver disease (MASLD) progression. |
| 2026 | Liebgott et al. “A Western-style diet shapes the gut and liver responses to low-dose, fit-for-purpose polystyrene nanoplastics in mice.” [31] | Mice, chow vs. Western diet | approximately 600 nm PS nanoplastics for 90 days | Low-dose PS-NPL exposure increased body-weight gain in a non-monotonic pattern, worsened glucose intolerance in Western-diet mice, and promoted hepatic lipid accumulation. |