CDetection.v2: One-pot assay for the detection of SARS-CoV-2.

Introduction: The ongoing 2019 coronavirus disease pandemic (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and its variants, is a global public health threat. Early diagnosis and identification of SARS-CoV-2 and its variants plays a critical role in COVID-19 prevention and control. Currently, the most widely used technique to detect SARS-CoV-2 is quantitative reverse transcription real-time quantitative PCR (RT-qPCR), which takes nearly 1 hour and should be performed by experienced personnel to ensure the accuracy of results. Therefore, the development of a nucleic acid detection kit with higher sensitivity, faster detection and greater accuracy is important. Methods: Here, we optimized the system components and reaction conditions of our previous detection approach by using RT-RAA and Cas12b. Results: We developed a Cas12b-assisted one-pot detection platform (CDetection.v2) that allows rapid detection of SARS-CoV-2 in 30 minutes. This platform was able to detect up to 5,000 copies/ml of SARS-CoV-2 without cross-reactivity with other viruses. Moreover, the sensitivity of this CRISPR system was comparable to that of RT-qPCR when tested on 120 clinical samples. Discussion: The CDetection.v2 provides a novel one-pot detection approach based on the integration of RT-RAA and CRISPR/Cas12b for detecting SARS-CoV-2 and screening of large-scale clinical samples, offering a more efficient strategy for detecting various types of viruses.

Perinatal exposure to diethyl-hexyl-phthalate induces obesity in mice.

The environmental obesogen hypothesis proposes that exposure to endocrine disruptors during developmental "window" contributes to adipogenesis and the development of obesity. Implication of environmental endocrine disruptor such as diethyl-hexyl-phthalate (DEHP) on adipose tissue development has been poorly investigated. Here, we evaluated the effects of DEHP on adipocyte differentiation in vitro and in vivo, and explored potential mechanism involved in its action. DEHP had no effect on adipocyte differentiation in the murine 3T3-L1 cell model, whereas DEHP induced the expression of transcriptional factors peroxisome proliferator-activated receptor (PPAR) gamma, CCAAT/enhancer-binding protein (C/EBP) alpha and sterol regulatory element binding factor 1 (Srebf1) as well as downstream target genes required for adipogenesis in vivo. Furthermore, perinatal exposure to DEHP had an impact on filial adipogenesis. Body weight, adipose tissue deposition, serum lipids and glucose levels were significantly elevated in offspring at postnatal day (PND) 60. Therefore, these results suggested that perinatal exposure to DEHP might be expected to increase the incidence of obesity in offspring and could act as a potential chemical stressor for obesity and obesity-related disorders.

The endocrine disruptor mono-(2-ethylhexyl) phthalate promotes adipocyte differentiation and induces obesity in mice.

The environmental obesogen hypothesis proposes that exposure to endocrine disruptors during developmental 'window' contributes to adipogenesis and the development of obesity. MEHP [mono-(2-ethylhexyl) phthalate], a metabolite of the widespread plasticizer DEHP [di-(2-ethylhexyl) phthalate], has been found in exposed organisms and identified as a selective PPARγ (peroxisome-proliferator-activated receptor γ) modulator. However, implication of MEHP on adipose tissue development has been poorly investigated. In the present study, we show the dose-dependent effects of MEHP on adipocyte differentiation and GPDH (glycerol-3-phosphate dehydrogenase) activity in the murine 3T3-L1 cell model. MEHP induced the expression of PPARγ as well as its target genes required for adipogenesis in vitro. Moreover, MEHP perturbed key regulators of adipogenesis and lipogenic pathway in vivo. In utero exposure to a low dose of MEHP significantly increased b.w. (body weight) and fat pad weight in male offspring at PND (postnatal day) 60. In addition, serum cholesterol, TAG (triacylglycerol) and glucose levels were also significantly elevated. These results suggest that perinatal exposure to MEHP may be expected to increase the incidence of obesity in a sex-dependent manner and can act as a potential chemical stressor for obesity and obesity-related disorders.

The endocrine disruptor 4-nonylphenol promotes adipocyte differentiation and induces obesity in mice.

BACKGROUND/AIM: The environmental obesogen hypothesis proposes that exposure to endocrine disruptors during developmental "window" contributes to adipogenesis and the development of obesity. Implication of environmental endocrine disruptor such as 4Nonylphenol (4-NP) on adipose tissue development has been poorly investigated. METHODS: 3T3-L1 preadipocytes were incubated with different doses of 4-NP. Six-week-old C57BL/6J male mice received an intraperitoneal injection of vehicle, troglitazone or 4-NP (0.5 mg/kg). Gene expression of adipogenic regulators was analyzed. Pregnant mice were dosed by gavage with vehicle or 4-NP (0.05, 0.25 or 0.5 mg/kg) from day 12 of gestation until day 7 of lactation. The body weight, liver weight, fat mass, and serum lipids and glucose levels were measured in offspring at postnatal day 60. RESULTS: Low concentration of 4-NP induced adipocyte differentiation, glycerol-3-phosphate dehydrogenase activity, and expression of peroxisome proliferator-acivated receptor γ as well as its target genes required for adipogenesis. 4-NP perturbed key regulators of adipogenesis and lipogenic pathway in vivo. Perinatal exposure to 4-NP increased body weight, fat mass, and serum total cholesterol and glucose levels in offspring. CONCLUSIONS: 4-NP may be expected to increase the incidence of obesity and can act as a potential chemical stressor for obesity and obesity-related disorders.

The endocrine disruptor diethylstilbestrol induces adipocyte differentiation and promotes obesity in mice.

Epidemiology studies indicate that exposure to endocrine disruptors during developmental "window" contributes to adipogenesis and the development of obesity. Implication of endocrine disruptor such as diethylstilbestrol (DES) on adipose tissue development has been poorly investigated. Here we evaluated the effects of DES on adipocyte differentiation in vitro and in vivo, and explored potential mechanism involved in its action. DES induced 3T3-L1 preadipocyte differentiation in a dose-dependent manner, and activated the expression of estrogen receptor (ER) and peroxisome proliferator-acivated receptor (PPAR) γ as well as its target genes required for adipogenesis in vitro. ER mediated the enhancement of DES-induced PPARγ activity. Moreover, DES perturbed key regulators of adipogenesis and lipogenic pathway in vivo. In utero exposure to low dose of DES significantly increased body weight, liver weight and fat mass in female offspring at postnatal day (PND) 60. In addition, serum triglyceride and glucose levels were also significantly elevated. These results suggest that perinatal exposure to DES may be expected to increase the incidence of obesity in a sex-dependent manner and can act as a potential chemical stressor for obesity and obesity-related disorders.