In Vitro Cellular & Developmental Biology. Animal最新文献

Tilapia parvovirus (TiPV) is an emerging viral pathogen and responsible for severe economic loss in tilapia culture production. Lethargic, cutaneous haemorrhages; ocular lesions; discolouration of gill and cloudy eye and exophthalmia are common symptoms of TiPV. The TiPV-suspected tilapia fish were collected from grow-out ponds situated in different parts of Tamil Nadu, India, and screened for TiPV by PCR. The results showed the presence of TiPV in disease-suspected fish which was further confirmed by PCR using different primer sets specific to different genomic regions of TiPV. Sequence analysis of 534 bp of genomic region of TiPV showed 100% similarity with the sequence of TiPV strain of Thailand and India. TiPV was found in different organs including eggs of infected fish and showed the possibility of systemic infection and vertical transmission. Snakehead kidney (CSK), snubnose pompano fin (SPF) and tilapia heart (TH) cell lines showed susceptibility to TiPV. The viral replication in cell lines was confirmed by PCR, TiPV-specific cytopathic effect of Cowdry A inclusion bodies with clear halo surrounding them and infectivity experiment. The disease was reproduced in normal fish by intramuscular route using viral inoculum from TiPV-infected fish or virus multiplied in susceptible cell lines to satisfy Koch's postulates.

Melatonin (MEL), functioning as a circulating hormone, is important for the regulation of ferroptosis in different health scenarios and acts as a crucial antioxidant in cardiovascular diseases. However, its specific function in ferroptosis related to myocardial ischemia-reperfusion injury (MIRI) remains to be fully elucidated. In our research, we utilized a rat model of MIRI induced by coronary artery ligation, along with a cell model subjected to hypoxia/reoxygenation (H/R). We evaluated relevant genes and proteins by real-time fluorescent quantitative PCR and Western blot analysis. To evaluate myocardial tissue damage and cell injury, we employed cell counting kit-8 assays, flow cytometry, hematoxylin-eosin staining, and 2,3,5-triphenyltetrazolium chloride staining techniques. Our results show that administering MEL notably reduces the concentrations of cTnT, CK-MB, and lactate dehydrogenase in the serum of MIRI rats, mitigates the extent of myocardial infarction, improves the recovery of pathological conditions in myocardial tissues, and reduces the concentrations of Fe²⁺, malondialdehyde (MDA), and reactive oxygen species (ROS) in the myocardial tissue, while also promoting increased glutathione levels. Moreover, MEL can also restore the reduced viability of H9C2 cells caused by H/R or ferroptosis inducers (RSL3), reduce the cellular content of Fe²⁺, MDA, and ROS, and inhibit ferroptosis. Mechanistically, MEL promotes the expression of GPX4 by downregulating the expression of ATF3, thereby inhibiting ferroptosis in cardiomyocytes and ultimately alleviating the process of MIRI. Our study demonstrates that MEL ameliorates MIRI by inhibiting ferroptosis.

The aim of this study is to assess the impact of Tianxiangdan (TXD) on lipophagy in foam cells and its underlying mechanism in treating atherosclerosis, particularly focusing on its efficacy in lowering blood lipids. In vivo, ApoE-/- atherosclerosis mouse models were established for group intervention. Blood lipid levels of the mice were measured, lipid deposition and autophagy levels in atherosclerotic plaques were assessed, and co-localization of lipid droplets and autophagosomes was examined. In vitro, human THP-1 cells were induced into macrophages and then transformed into foam cells using ox-LDL induction. Different intervention groups were established. Total cellular cholesterol (TC), free cholesterol (FC), and autophagy levels were assessed, while the morphology and distribution of lipid droplets and autophagosomes in cells were observed using transmission electron microscopy. Western blot analysis was performed to evaluate the expression levels of PI3K, Akt, mTOR, TFEB, LC3II/I, ULK1, ABCA1, and p62. TXD effectively lowers blood lipid levels in ApoE-/- atherosclerotic mice, enhances lipophagy, and reduces lipid accumulation in foam cells and arterial lipid plaques. It achieves this by suppressing the expression of p85, Akt, and mTOR, while activating downstream autophagy signals such as TFEB, LC3II/I, and ULK1. Additionally, TXD reduces the expression of p62 and enhances the expression of the cholesterol transport molecule ABCA1. Our findings indicate that TXD activates lipophagy via the PI3K/Akt/mTOR pathway, leading to a reduction in lipid deposition within foam cells and plaques, thereby mitigating atherosclerosis.

Atherosclerosis (AS) is a prevalent cardiovascular condition, and the growth and phenotypic switch of vascular smooth muscle cells (VSMCs) play a crucial role in its development. Studies have revealed that the activation of certain transcription factors and signaling pathways can trigger these cellular changes. Consequently, targeting these pathways and pivotal molecules has emerged as a promising strategy for AS treatment. Drugs that can reverse the cellular changes in VSMCs may offer new therapeutic options for AS, marking a significant advancement. While previous research has suggested that urolithin B (Uro B) possesses anti-atherosclerotic properties, its exact mechanism remains to be fully understood, especially the effect of Uro B in VSMCs. This study discovered that Uro B can impede the proliferation and migration of VSMCs prompted by PDGF-BB, as well as their phenotypic changes, indicating that Uro B could potentially prevent AS by inhibiting the phenotypic switch of VSMCs.

Long dsRNA induces the expression of type I interferons (IFNs) and IFN-stimulated genes (ISGs) to establish an antiviral state. When induced prophylactically, this antiviral state can reduce the severity and mortality of viral infections. One of the limiting factors in delivering dsRNA in animal models is the lack of an effective carrier that protects the dsRNA from degradation in the extracellular space. In this study, commercially available cationic liposomes composed of stearylamine, L-α-phosphatidylcholine, and cholesterol were analyzed for their ability to encapsulate and deliver a 621-bp dsRNA sequence. This encapsulated dsRNA was delivered to two Oncorhynchus mykiss cell lines, RTG-2 and RTgill-W1, to activate the IFN pathway and reduce chum salmon reovirus (CSV) infection. EMSA analysis revealed that the liposomes effectively encapsulated 55 and 800 µg/mL doses of dsRNA, remained stable when stored at 4°C and - 20°C, and protected the encapsulated dsRNA from degradation by RNase III. Cell viability assays determined that liposomes loaded with dsRNA were highly cytotoxic after 24 h of exposure. A shorter exposure of 2 h resulted in reduced cytotoxicity and enhanced expression of the ISG Mx1 in both dsRNA alone and dsRNA-liposome-treated cells; however, the elevated Mx1 induction was not sufficient in the dsRNA-liposome treatment group to provide protection against viral infection. Meanwhile, the unencapsulated dsRNA significantly reduced the CSV titer and amount of syncytia formation. Thus, while dsRNA represents an important immune modulator in fish cells, this liposome formulation is too toxic for antiviral applications.

Grouper muscle satellite cells (GMSCs) from the seven-band grouper (Epinephelus septemfasciatus) were isolated, and their growth conditions were optimized (10% fetal bovine serum, 24°C, 10 ng/mL bFGF). The cells were immortalized at passage 14 and designated as grouper immortalized muscle satellite cells (GIMSCs). DNA barcoding confirmed the grouper origin of both GMSC and GIMSC lines. GIMSCs exhibited enhanced proliferation, accelerated differentiation, and robust myotube formation compared to pre-crisis GMSCs. Western blot analysis showed upregulation of key myogenic factors (Pax7, MyoD, MyoG) and structural proteins (Desmin) in GIMSC, indicating the differentiation potential. The immortalized GIMSC line maintained consistent morphology, growth rates, and viability across multiple passages. Biocompatibility studies showed GIMSCs were compatible with bio-inks (sodium alginate, gelatin, κ-carrageenan) at 250 to 10,000 µg/mL, retaining ~ 80% viability at the highest concentration. Taste sensory analysis revealed GMSCs had the highest umami and lowest saltiness and sourness, contrasting with the muscle of the seven-band grouper, which had higher saltiness and sourness. Flavor analysis identified pronounced fishy, hot fat, and ethereal flavors in the cells at higher level than in the muscle. These findings suggest GMSCs and GIMSCs are promising for producing cultured meat with enhanced umami taste and flavors, advancing cellular agriculture and sustainable food production.

Bone fractures are a prevalent clinical issue, and recent studies highlighted the promising potential of natural bone healing agents in enhancing fracture repair and regeneration. The regulatory interaction mechanism between osteoblasts and osteoclasts is crucial for bone cell biology and bone disease. In Mongolian medicine, people have used the Rhodiola rosea (R. rosea) extract to accelerate bone healing in bone fractures. Salidroside is a bioactive compound of R. rosea. Salidroside is known to regulate bone metabolism and inhibit the activation of osteoclast cells, but how it affects the differentiation of osteoclasts is unknown. We examined the effect of R. rosea extract and its bioactive compound salidroside on the RANKL-induced osteoclast formation in RAW 264.7 cells. The present study observed that salidroside directly inhibits RANKL-induced TRAP-positive osteoclast formation. Immunoblotting analysis revealed that salidroside inhibited the expression of c-Fos and NFATc1, osteoclastogenic key transcription factors, by suppressing late activation of p65 NFκB. Further, the ethanol extracts of R. rosea significantly reduced the RANKL-induced osteoclasts in a dose-dependent manner. In conclusion, salidroside inhibits RANKL-induced osteoclast formation via suppressing the NFκB/c-Fos/NFATc1 signalling pathway. R. rosea, a primary source of salidroside, is helpful for bone healing via its inhibitory effect on osteoclast formation.

Acetate can promote milk fat synthesis in dairy cow mammary epithelial cells (BMECs). In this study, gene function analysis was used to explore the role of Ras family secretion-related GTP binding protein 1B (SAR1B) in milk fat synthesis of BMECs and its role and molecular mechanism in acetate-promoted milk fat synthesis. We found that the synthesis of lipid droplets and triglycerides was inhibited, and the expression levels of key genes and proteins in milk fat synthesis such as FASN and ACC were decreased in SAR1B knockout, which was reversed by overexpression of SAR1B. Addition of sodium acetate in BMECs can promote the expression of SAR1B, and SAR1B plays an important role in the synthesis of milk fat promoted by sodium acetate. We further investigated the underlying mechanism of SAR1B upregulation by sodium acetate, and found that sodium acetate could affect SAR1B expression through the positive regulation of SAR1B gene promoter activity by C/EBPβ and PPARγ. In conclusion, the results suggest that SAR1B can promote milk fat synthesis in BMECs, while C/EBPβ and PPARγ play important roles in sodium acetate to promote the expression of SAR1B.