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Cardiovascular disease is one of the leading causes of death worldwide and has a high prevalence. Insulin‐like growth factor‐II receptor α (IGF‐IIRα) acts as a stress‐inducible negative regulator. This study focused on the substantial impact of heightened expression of IGF‐IIRα in cardiac myoblasts and its association with the exacerbation of cardiac dysfunction. Using lipopolysaccharide (LPS)‐induced H9c2 cardiac myoblasts as a model for sepsis, we aimed to elucidate the molecular interactions between IGF‐IIRα and LPS in exacerbating cardiac injury. Our findings demonstrated a synergistic induction of cardiac inflammation and hypertrophy by LPS stimulation and IGF‐IIRα overexpression, leading to decreased cell survival. Excessive calcineurin activity, triggered by this combined condition, was identified as a key factor exacerbating the negative effects on cell survival. Cellular changes such as cell enlargement, disrupted actin filaments, and upregulation of hypertrophy‐related and inflammation‐related proteins contributed to the overall hypertrophic and inflammatory responses. Overexpression of IGF‐IIRα also exacerbated apoptosis induced by LPS in H9c2 cardiac myoblasts. Inhibiting calcineurin in LPS‐treated H9c2 cardiac myoblasts with IGF‐IIRα overexpression effectively reversed the detrimental effects, reducing cell damage and mitigating apoptosis‐related cardiac mechanisms. Our study suggests that under sepsis‐like conditions in the heart with IGF‐IIRα overexpression, hyperactivation of calcineurin worsens cardiac damage. Suppressing IGF‐IIRα and calcineurin expression could be a potential intervention to alleviate the impact of the illness and improve cardiac function. [ABSTRACT FROM AUTHOR]

Oxidative stress is a pivotal factor in the pathogenesis of various cardiovascular diseases. Rhodiola, a traditional Chinese medicine, is recognized for its potent antioxidant properties. Salidroside, a phenylpropanoid glycoside derived from Rhodiola rosea, has shown remarkable antioxidant capabilities. This study aimed to elucidate the potential protective mechanisms of Rhodiola and salidroside against H2O2‐induced cardiac apoptosis in H9c2 cardiomyoblast cells. H9c2 cells were exposed to H2O2 for 4 h, and subsequently treated with Rhodiola or salidroside for 24 h. Cell viability and apoptotic pathways were assessed. The involvement of insulin‐like growth factor 1 receptor (IGF1R) and the activation of extracellular regulated protein kinases 1/2 (ERK1/2) were investigated. H2O2 (100 μM) exposure significantly induced cardiac apoptosis in H9c2 cells. However, treatment with Rhodiola (12.5, 25, and 50 μg/mL) and salidroside (0.1, 1, and 10 nM) effectively attenuated H2O2‐induced cytotoxicity and apoptosis. This protective effect was associated with IGF1R‐activated phosphorylation of ERK1/2, leading to the inhibition of Fas‐dependent proteins, HIF‐1α, Bax, and Bak expression in H9c2 cells. The images from hematoxylin and eosin staining and immunofluorescence assays also revealed the protective effects of Rhodiola and salidroside in H9c2 cells against oxidative damage. Our findings suggest that Rhodiola and salidroside possess antioxidative properties that mitigate H2O2‐induced apoptosis in H9c2 cells. The protective mechanisms involve the activation of IGF1R and subsequent phosphorylation of ERK1/2. These results propose Rhodiola and salidroside as potential therapeutic agents for cardiomyocyte cytotoxicity and apoptosis induced by oxidative stress in heart diseases. Future studies may explore their clinical applications in cardiac health. [ABSTRACT FROM AUTHOR]

The primary function of the skin is to form a mechanical, permeability, antimicrobial, and ultraviolet radiation barrier, which is essential for maintaining physiological homeostasis. Our previous studies demonstrated that cutaneous pigmentation could promote skin barrier function in addition to providing anti‐ultraviolet irradiation defense. The present study aimed to develop a new regimen that enhances skin barrier function by regulating skin pigmentation using low‐concentration imiquimod. Results showed that topical application of low‐concentration imiquimod effectively induced skin hyperpigmentation in the dorsal skin and external ear of mice without inducing inflammatory cell infiltration. An in vitro study also revealed that low‐concentration imiquimod did not induce any cytotoxic effects on melanoma cells but triggered excessive melanin synthesis. In coculture systems, low‐concentration imiquimod was noted to increase tyrosinase activity in a broader cellular context, revealing the potential role of neighboring cells in melanin production. The next‐generation sequencing result indicated that PKCη and Dnm3 might regulate melanin synthesis and release during imiquimod treatment. Overall, our study presents new insights into the regulation of melanin production by low‐concentration imiquimod, both in a mice model and cultured cells. Furthermore, our study highlights the potential benefits of imiquimod in promoting melanin synthesis without causing skin disruptions or inducing inflammation, validating its potential to serve as a method for enhancing skin barrier functions by regulating the epidermal melanization reaction. [ABSTRACT FROM AUTHOR]

Platycodi radix is a widely used herbal medicine that contains numerous phytochemicals beneficial to health. The health and biological benefits of P. radix have been found across various diseases. The utilization of umbilical cord stromal stem cells, derived from Wharton's jelly of the human umbilical cord, has emerged as a promising approach for treating degenerative diseases. Nevertheless, growing evidence indicates that the function of stem cells declines with age, thereby limiting their regenerative capacity. The primary objective in this study is to investigate the beneficial effects of P. radix in senescent stem cells. We conducted experiments to showcase that diminished levels of Lamin B1 and Sox‐2, along with an elevation in p21, which serve as indicative markers for the senescent stem cells. Our findings revealed the loss of Lamin B1 and Sox‐2, coupled with an increase in p21, in umbilical cord stromal stem cells subjected to a low‐dose (0.1 μM) doxorubicin (Dox) stimulation. However, P. radix restored the Dox‐damage in the umbilical cord stromal stem cells. P. radix reversed the senescent conditions when the umbilical cord stromal stem cells exposed to Dox‐induced reactive oxygen species (ROS) and mitochondrial membrane potential are significantly changed. In Dox‐challenged aged umbilical cord stromal stem cells, P. radix reduced senescence, increased longevity, prevented mitochondrial dysfunction and ROS and protected against senescence‐associated apoptosis. This study suggests that P. radix might be as a therapeutic and rescue agent for the aging effect in stem cells. Inhibition of cell death, mitochondrial dysfunction and aging‐associated ROS with P. radix provides additional insights into the underlying molecular mechanisms. [ABSTRACT FROM AUTHOR]

Heat shock proteins (HSPs), which function as chaperones, are activated in response to various environmental stressors. In addition to their role in diverse aspects of protein production, HSPs protect against harmful protein-related stressors. Calycosin exhibits numerous beneficial properties. This study aims to explore the protective effects of calycosin in the heart under heat shock and determine its underlying mechanism. H9c2 cells, western blot, TUNEL staining, flow cytometry, and immunofluorescence staining were used. The time-dependent effects of heat shock analyzed using western blot revealed increased HSP expression for up to 2 h, followed by protein degradation after 4 h. Hence, a heat shock damage duration of 4 h was chosen for subsequent investigations. Calycosin administered post-heat shock demonstrated dose-dependent recovery of cell viability. Under heat shock conditions, calycosin prevented the apoptosis of H9c2 cells by upregulating HSPs, suppressing p-JNK, enhancing Bcl-2 activation, and inhibiting cleaved caspase 3. Calycosin also inhibited Fas/FasL expression and activated cell survival markers (p-PI3K, p-ERK, p-Akt), indicating their cytoprotective properties through PI3K/Akt activation and JNK inhibition. TUNEL staining and flow cytometry confirmed that calycosin reduced apoptosis. Moreover, calycosin reversed the inhibitory effects of quercetin on HSF1 and Hsp70 expression, illustrating its role in enhancing Hsp70 expression through HSF1 activation during heat shock. Immunofluorescence staining demonstrated HSF1 translocation to the nucleus following calycosin treatment, emphasizing its cytoprotective effects. In conclusion, calycosin exhibits pronounced protective effects against heat shock-induced damages by modulating HSP expression and regulating key signaling pathways to promote cell survival in H9c2 cells. [ABSTRACT FROM AUTHOR]