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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 most effective drug, doxorubicin (DOX), is widely used worldwide for clinical application as an anticancer drug. DOX‐induced cytotoxicity is characterized by mitochondrial dysfunction. There is no alternative treatment against DOX‐induced cardiac damage despite intensive research in the present decades. Ohwia caudata has emerged as a potential herbal remedy that prevents from DOX‐induced cytotoxicity owing to its pharmacological action of sustaining mitochondrial dynamics by attenuating oxidative stress and inducing cellular longevity. However, its underlying mechanisms are unknown. The novel treatment provided here depends on new evidence from DOX‐treated H9c2 cells, which significantly enhanced insulin‐like growth factor (IGF) II receptor (IGF‐IIR) pathways that activated calcineurin and phosphorylated dynamin‐related protein 1 (p‐Drp1) at ser616 (p‐Drp1[ser616]); cells undergo apoptosis due to these factors, which translocate to mitochondria and disrupt their function and integrity, and in terms of herbal medicine treatment, which significantly blocked these phenomena. Thus, our findings indicate that maintaining integrity of mitochondria is an essential element in lowering DOX‐induced cytotoxicity, which further emphasizes that our herbal medicine can successfully block IGF‐IIR pathways and could potentially act as an alternative mechanism in terms of cardioprotective against doxorubicin. [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]

Fibroblast‐like synoviocytes accumulation, proliferation and activation, and the subsequent inflammatory mediators production play a key role in the progression of rheumatoid arthritis (RA). It is well established that Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling triggers inflammation, and induces cytokine levels in RA. Ohwia caudata have long been used against many disorders. However, in RA, the effects of O. caudata have not been elucidated. In the current study, synoviocytes were used to evaluate the suppressive effects of O. caudate extract (OCE) on the pro‐inflammatory cytokines production. In vitro, the underlying mechanisms by which OCE inhibits inflammatory response through regulation of suppressors of cytokine signaling 3 (SOCS3) and JAK2/STAT3 expression in IL‐17A‐treated HIG‐82 synoviocytes were investigated. The results demonstrated that the proliferation of IL‐17A‐challenged cells were increased in comparison with non‐stimulated control cells. The synoviocyte proliferation was decreased significantly of OCE concentrations in dose dependent manner. The p‐JAK2, p‐STAT3, interleukin (IL)‐1β, and IL‐6 were reduced in IL‐17A‐challenged cells treated with OCE. Furthermore, AZD1480 (a JAK2‐specific inhibitor) or WP1066 (a STAT3‐specific inhibitor) affected the inflammatory mediators production in IL‐17A‐challenged synoviocytes, and OCE failed to mitigate the IL‐17A‐induced inflammatory mediators and SOCS3, acting as a feedback inhibitor of the JAK/STAT3 pathway, in the presence of SOCS3 siRNA, indicating that the beneficial effects of OCE on the regulation of inflammatory response homeostasis were dependent on SOCS3 and the JAK2/STAT3 signaling pathway. Our study also showed that SOCS3 was markedly activated by OCE in RA fibroblast‐like synoviocytes, thereby decreasing the JAK/STAT3 pathway, and the IL‐1β, and IL‐6 activation. Thus, O. caudate should be further investigated as a candidate anti‐inflammatory and anti‐arthritic agent. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD), a chronic and progressive neurodegenerative disease, can reduce the population of dopaminergic neurons in the substantia nigra. The cause of this neuronal death remains unclear. 1‐Methyl‐4‐phenylpyridinium ion (MPP+) is a potent neurotoxin that can destroy dopaminergic (DA) neurons and promote PD. Garcinol, a polyisoprenylated benzophenone derivative, was extracted from Garcinia indica and is an important active compound it has been used as an anticancer, antioxidant, and anti‐inflammatory, agent and it can suppress reactive oxygen species (ROS) mediated cell death in a PD model. Human neuroblastoma (SH‐SY5Y) cells (1 × 105 cells) were treated with MPP+ (1 mM) for 24 h to induce cellular ROS production. The formation of ROS was suppressed by pretreatment with different concentrations of garcinol (0.5 and 1.0 μM) for 3 h in SH‐SY5Y cells. The present study found that MPP+ treatment increased the formation of reactive oxygen species (ROS), and the increased ROS began to promote cell death in SH‐SY5Y cells. However, our natural compound garcinol effectively blocked MPP+‐mediated ROS formation by activating the DJ‐1/SIRT1 and PGC‐1α mediated antioxidant pathway. Further findings indicate that the activated SIRT1 can also regulate p‐AMPK‐mediated autophagy to protect the neurons from the damage it concludes that garcinol sub‐sequential regulates intracellular autophagy in this model, and the productive efficacy of garcinol was confirmed by western blot analysis and MitoSOX DCFDA and MTT assays. The results showed garcinol increased protection due to the prevention of MPP+‐induced ROS and the promotion of cell survival. [ABSTRACT FROM AUTHOR]

Diabetes‐induced cardiovascular complications are mainly associated with high morbidity and mortality in patients with diabetes. Insulin‐like growth factor II receptor α (IGF‐IIRα) is a cardiac risk factor. In this study, we hypothesized IGF‐IIRα could also deteriorate diabetic heart injury. The results presented that both in vivo transgenic Sprague–Dawley rat model with specific IGF‐IIRα overexpression in the heart and in vitro myocardium H9c2 cells were used to investigate the negative function of IGF‐IIRα in diabetic hearts. The results showed that IGF‐IIRα overexpression aided hyperglycemia in creating more myocardial injury. Pro‐inflammatory factors, such as Tumor necrosis factor‐alpha, Interleukin‐6, Cyclooxygenase‐2, Inducible nitric oxide synthase, and Nuclear factor‐kappaB inflammatory cascade, are enhanced in the diabetic myocardium with cardiac‐specific IGF‐IIRα overexpression. Correspondingly, IGF‐IIRα overexpression in the diabetic myocardium also reduced the PI3K‐AKT survival axis and activated mitochondrial‐dependent apoptosis. Finally, both ejection fraction and fractional shortening were be significantly decrease in diabetic rats with cardiac‐specific IGF‐IIRα overexpression. Overall, all results provid clear evidence that IGF‐IIRα can enhance cardiac damage and is a harmful factor to the heart under high‐blood glucose conditions. However, the pathophysiology of IGF‐IIRα under different stresses and its downstream regulation in the heart still require further research. [ABSTRACT FROM AUTHOR]

Different stress condition stimulates the expression level of insulin‐like growth factor receptor II (IGF‐IIR) in cardiomyoblasts that lead to apoptosis. Tanshinone IIA (TSN), a pharmacologically active component from Danshen, has been shown cardioprotective effects against cardiac apoptosis induced by several stress conditions. Therefore, this study was conducted to assess the cardioprotective effects of TSN IIA mediated through the estrogen receptor (ER) in order to inhibit the Leu27IGF‐II‐enhanced IGF‐IIR‐mediated cardiac apoptosis. The estrogenic activity of TSN IIA was examined after myocardial cells were pretreated with the ER antagonist, and inhibited the phospho‐inositide‐3 kinase (PI3K). Here, we found that TSN IIA significantly induced ER that phosphorylated Akt. Further, Akt activation considerably suppressed the Leu27IGF‐II induced IGF‐IIR expression level and the downstream effectors, including Gαq and calcineurin as well as mitochondrial dependent apoptosis proteins including Bad, cytochrome c, and active caspase‐3 that result in cardiac apoptosis resistance. However, the western blot analysis, JC‐1 staining, and terminal deoxynucleotide transferase‐mediated dUTP nick end labeling assay revealed that TSN IIA attenuated Leu27IGF‐II‐induced IGF‐IIR mediated cardiac apoptosis was reversed by an ER antagonist such as ICI 182780, and PI3K inhibition. All these findings demonstrate that TSN IIA exerts estrogenic activity, which can activate PI3K‐Akt pathway, and thereby inhibits Leu27IGFII induced IGF‐IIR mediated cardiac apoptosis. Thus, TSN IIA can be considered as an effective therapeutic strategy against IGF‐IIR signaling cascade to suppress cardiac apoptosis. [ABSTRACT FROM AUTHOR]