ABSTRACT
ObjectiveTo explore whether miR-375 regulates the malignant characteristics of osteosarcoma (OS) by influencing the expression of MMP13. MethodsPlasmid DNAs and miRNAs were transfected into OS cells and HEK293 cells using Lipofectamine 3000 reagent. Real-time quantitative polymerase chain reaction was performed to measure the expression of miR-375 and MMP13 in OS patients and OS cells. Western blot was performed to analyze the MMP13 protein in the patients with OS and OS cells. The targeting relationship between miR-375 and MMP13 was analyzed by luciferase assay. Migration and invasion were analysed by heal wound and transwell assays, respectively. ResultsmiR-375 expression in OS tissues was lower than that in normal tissues. The expression of MMP13 was upregulated in OS tissues. MMP13 expression was negatively correlated withmiR-375 expression in patients with OS. Migration and invasion were significantly inhibited in OS cells with the miR-375 mimic compared with OS cells with the miRNA control. MMP13 partially reversed the inhibition of migration and invasion induced by miR-375 in the OS cells. ConclusionmiR-375 attenuates migration and invasion by downregulating the expression of MMP13 in OS cells.
ABSTRACT
Mitophagy, a highly precise form of autophagy, plays a pivotal role in maintaining cellular homeostasis by selectively targeting and eliminating damaged mitochondria through a process known as mitophagy. Within this tightly regulated mechanism, dysfunctional mitochondria are specifically delivered to lysosomes for degradation. Disruptions in mitophagy have been implicated in a diverse range of pathological conditions, spanning diseases of the nervous system, cardiovascular system, cancer, aging, and metabolic syndrome. The elucidation of mitophagy’s impact on cardiovascular disorders, liver diseases, metabolic syndromes, immune dysfunctions, inflammatory conditions, and cancer has significantly advanced our understanding of the complex pathogenesis underlying these conditions. These studies have shed light on the intricate connections between dysfunctional mitophagy and disease progression. Among the disorders associated with mitochondrial dysfunction, insulin resistance (IR) stands out as a prominent condition linked to metabolic disorders. IR is characterized by a diminished response to normal levels of insulin, necessitating higher insulin levels to trigger a typical physiological reaction. Hyperinsulinemia and metabolic disturbances often coexist with IR, primarily due to defects in insulin signal transduction. Oxidative stress, stemming from mitochondrial dysfunction, exerts dual effects in the context of IR. Initially, it disrupts insulin signaling pathways and subtly contributes to the development of IR. Additionally, by inducing mitochondrial damage and autophagy, oxidative stress indirectly impedes insulin signaling pathways. Consequently, mitophagy acts as a protective mechanism, encapsulating damaged or dysfunctional mitochondria through the autophagy-lysosome pathway. This efficient process eliminates excessive oxidative stress reactive. The intricate interplay between mitochondrial function, oxidative stress, mitophagy, and IR represents a captivating field of investigation in the realm of metabolic disorders. By unraveling the underlying complexities and comprehending the intricate relationships between these intertwined processes, researchers strive toward uncovering novel therapeutic strategies. With a particular focus on mitochondrial quality control and the maintenance of redox homeostasis, these interventions hold tremendous potential in mitigating IR and enhancing overall metabolic health. Emerging evidence from a myriad of studies has shed light on the active involvement of mitophagy in the pathogenesis of metabolic disorders. Notably, interventions such as exercise, drug therapies, and natural products have been documented to induce mitophagy, thereby exerting beneficial effects on metabolic health through the activation of diverse signaling pathways. Several pivotal signaling molecules, including AMPK, PINK1/Parkin, BNIP3/Nix, and FUNDC1, have been identified as key regulators of mitophagy and have been implicated in the favorable outcomes observed in metabolic disorders. Of particular interest is the unique role of PINK1/Parkin in mitophagy compared to other proteins involved in this process. PINK1/Parkin exerts influence on mitophagy through the ubiquitination of outer mitochondrial membrane proteins. Conversely, BNIP3/Nix and FUNDC1 modulate mitophagy through their interaction with LC3, while also displaying certain interrelationships with each other. In this comprehensive review, our objective is to investigate the intricate interplay between mitophagy and IR, elucidating the relevant signaling pathways and exploring the treatment strategies that have garnered attention in recent years. By assimilating and integrating these findings, we aim to establish a comprehensive understanding of the multifaceted roles and intricate mechanisms by which mitophagy influences IR. This endeavor, in turn, seeks to provide novel insights and serve as a catalyst for further research in the pursuit of innovative treatments targeting IR.
ABSTRACT
Di-(2-ethylhexyl) phthalate (DEHP) is currently one of the most widely used plasticizers, widely found in all kinds of items, such as children’s toys and food packaging materials, but also added to wallpaper, cable protective agents and other building decoration materials. DEHP is toxic and absorbed by the human body through respiratory tract, digestive tract and skin contact, which can cause damage to multiple systems, especially the male reproductive system, and testis is an important target organ. Oxidative stress injury is the core mechanism of spermatogenesis disorder caused by DEHP. DEHP exposure can cause oxidative stress or reactive oxygen species (ROS) increase in germ cells, and on this basis, promote cell apoptosis or cause excessive autophagy. The toxicity of DEHP to Leydig cells is mainly to interfere with the synthesis of steroid hormones. For Sertoli cells, ferroptosis and destruction of the blood-testis barrier are common injury mechanisms. In addition, gene methylation caused by DEHP not only affects the spermatogenic process, but also has epigenetic effects on offspring. In this paper, we reviewed the pathological damage, germ cell toxicity and epigenetic effects of DEHP on testis, and focused on the damage and molecular mechanism on testicular spermatogenic cells, Leydig cells and Sertoli cells. Future research is required to elucidate the body’s clearance mechanism and treatment plan after exposure to DEHP and whether DEHP will damage the function of myoid cells. It is hoped that this can provide new ideas for prevention and treatment of male reproductive disorders resulting from long-term exposure to plastic products.
ABSTRACT
To investigate the effect and mechanism of serum amyloid A (SAA) on the expression of scavenger receptor class B type I (SR-BI) and inflammatory response in THP-1 macrophages, the human THP-1 cells were treated with SAA and p38-MAPK agonist (anisomycin) or p38-MAPK inhibitor (SB203580). Then, the expressions of SR-BI, phosphorylated p38-MAPK and inflammatory factors (MCP-1, TNF-α, IL-1β) were examined by real-time quantitative PCR, Western blotting and ELISA, respectively. The results showed that, compared with control group, SAA increased the levels of inflammatory factors (MCP-1, TNF-α, IL-1β), down-regulated the expressions of SR-BI, and up-regulated the expression of phosphorylated p38-MAPK protein in a concentration- and time-dependent manner in THP-1 cells (P < 0.05). After treatment with SAA and p38-MAPK agonist (anisomycin) in THP-1 cells, the expression of SR-BI was down-regulated, and the levels of inflammatory factors and phosphorylated p38-MAPK protein expression were increased, compared with the group only treated by SAA (P < 0.05). In contrast, the SR-BI expression was up-regulated, whereas inflammatory factors and phosphorylated p38-MAPK protein expressions were decreased after the cells were treated with SAA and p38-MAPK inhibitor (SB203580) (P < 0.05). The results suggest that SAA-promoted inflammatory response in THP-1 macrophages may be through the phosphorylation of p38-MAPK and inhibition of SR-BI expression.
Subject(s)
Humans , Cell Line , Chemokine CCL2 , Inflammation , Interleukin-1beta , MAP Kinase Signaling System , Macrophages , Phosphorylation , Serum Amyloid A Protein , Tumor Necrosis Factor-alpha , p38 Mitogen-Activated Protein KinasesABSTRACT
<p><b>AIM</b>To study the expressions of scavenger receptor class B type I(SR-BI) and peroxisome proliferator-activated receptor gamma (PPARgamma) in atherosclerotic mini swine and provide a new mechanism for investigating the pathogenesis of atherosclerosis.</p><p><b>METHODS</b>Chinese mini swine were fed by a normal control diet or a high fat/high cholesterol diet for 12 months after common carotid artery injury induced by balloon denudation. Plasma total cholesterol(TC), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG) were determined by commercially enzymatic methods every two months. The sections, which were taken from liver and abdominal aorta, were stained with hematoxylin eosin. The expressions of SR-BI and PPARgamma mRNA and protein in liver and aorta tissue were detected by reverse transcriptase-polymerase chain reaction (RT-PCR), Western blot and immunohistochemistry respectively.</p><p><b>RESULTS</b>At the end of 12 months, plasma TC, HDL-C and TG in HFHC mini swine were increased. There were fatty liver and atherosclerotic plaque in mini swine live and aorta respectively. The expression of SR-BI was upregulated in HFHC mini swine liver and aorta tissue.</p><p><b>CONCLUSION</b>HFHC may induce atherosclerosis and the expression of SR-BI and PPARgamma. Upregulating SR-BI expression may inhibit atherosclerosis. Increasing SR-BI expression in liver and aorta may accelerate SR-BI-mediated reverse cholesterol transport and develop a new anti-atherogenic strategy.</p>
