Carnosol alleviates nonalcoholic fatty liver disease by inhibiting mitochondrial dysfunction and apoptosis through targeting of PRDX3

Carnosol prevents cardiac remodeling and ventricular arrhythmias in pressure overload-induced heart failure mice

Cardiac remodeling is a commonly observed pathophysiological phenomenon associated with the progression of heart failure in various cardiovascular disorders. Carnosol, a phenolic compound extracted from rosemary, possesses noteworthy pharmacological properties including anti-inflammatory, antioxidant, and anti-apoptotic activities. Considering the pivotal involvement of inflammation, oxidative stress, and apoptosis in cardiac remodeling, the present study aims to assess the effects of carnosol on cardiac remodeling and elucidate the underlying mechanisms. In an in vivo model, cardiac remodeling was induced by performing transverse aortic constriction (TAC) surgery on mice, while an in vitro model was established by treating neonatal rat cardiomyocytes (NRCMs) with Ang II. Our results revealed that carnosol treatment effectively ameliorated TAC-induced myocardial hypertrophy and fibrosis, thereby attenuating cardiac dysfunction in mice. Moreover, carnosol improved cardiac electrical remodeling and restored connexin 43 expression, thereby reducing the vulnerability to ventricular fibrillation (VF). Furthermore, carnosol significantly reduced Ang II-induced cardiomyocyte hypertrophy in NRCMs and alleviated the upregulation of hypertrophy and fibrosis markers. Both in vivo and in vitro models of cardiac remodeling exhibited the anti-inflammatory, anti-oxidative, and anti-apoptotic effects of carnosol. Mechanistically, these effects were mediated through the Sirt1/PI3K/AKT pathway, as the protective effects of carnosol were abrogated upon inhibition of Sirt1 or activation of the PI3K/AKT pathway. In summary, our study suggests that carnosol prevents cardiac structural and electrical remodeling by regulating the anti-inflammatory, anti-oxidative, and anti-apoptotic effects mediated by Sirt1/PI3K/AKT signaling pathways, thereby alleviating heart failure and VF.

Carnosol alleviates sepsis-induced pulmonary endothelial barrier dysfunction by targeting nuclear factor erythroid2-related factor 2/sirtuin-3 signaling pathway to attenuate oxidative damage

Excessive reactive oxygen species production during acute lung injury (ALI) will aggravate the inflammatory process and endothelial barrier dysfunction. Carnosol is a natural phenolic diterpene with antioxidant and anti-inflammatory properties, but its role in treating sepsis-induced ALI remains unclear. This study aims to explore the protective effects and underlying mechanisms of carnosol in sepsis-induced ALI. C57BL/6 mouse were preconditioned with carnosol for 1 h, then the model of lipopolysaccharide (LPS)-induced sepsis was established. The degree of pulmonary edema, oxidative stress, and inflammation were detected. Endothelial barrier function was evaluated by apoptosis and cell junctions. In vitro, Mito Tracker Green probe, JC-1 staining, and MitoSOX staining were conducted to investigate the effect of carnosol on mitochondria. Finally, we investigated the role of nuclear factor-erythroid 2-related factor (Nrf2)/sirtuin-3 (SIRT3) in carnosol against ALI. Carnosol alleviated LPS-induced pulmonary oxidative stress and inflammation by inhibiting excess mitochondrial reactive oxygen species production and maintaining mitochondrial homeostasis. Furthermore, carnosol also attenuated LPS-induced endothelial cell barrier damage by reducing vascular endothelial cell apoptosis and restoring occludin, ZO-1, and vascular endothelial-Cadherin expression in vitro and in vivo. In addition, carnosol increased Nrf2 nuclear translocation to promote SIRT3 expression. The protective effects of carnosol on ALI were largely abolished by inhibition of Nrf2/SIRT3. Our study has provided the first evidence that the Nrf2/SIRT3 pathway is a protective target of the endothelial barrier in ALI, and carnosol can serve as a potential therapeutic candidate for ALI by utilizing its ability to target this pathway.

Carnosol ameliorated cancer cachexia-associated myotube atrophy by targeting P5CS and its downstream pathways

Introduction: Carnosol exhibited ameliorating effects on muscle atrophy of mice developed cancer cachexia in our previous research. Method: Here, the ameliorating effects of carnosol on the C2C12 myotube atrophy result from simulated cancer cachexia injury, the conditioned medium of the C26 tumor cells or the LLC tumor cells, were observed. To clarify the mechanisms of carnosol, the possible direct target proteins of carnosol were searched using DARTS (drug affinity responsive target stability) assay and then confirmed using CETSA (cellular thermal shift assay). Furthermore, proteomic analysis was used to search its possible indirect target proteins by comparing the protein expression profiles of C2C12 myotubes under treatment of C26 medium, with or without the presence of carnosol. The signal network between the direct and indirect target proteins of carnosol was then constructed. Results: Our results showed that, Delta-1-pyrroline-5-carboxylate synthase (P5CS) might be the direct target protein of carnosol in myotubes. The influence of carnosol on amino acid metabolism downstream of P5CS was confirmed. Carnosol could upregulate the expression of proteins related to glutathione metabolism, anti-oxidant system, and heat shock response. Knockdown of P5CS could also ameliorate myotube atrophy and further enhance the ameliorating effects of carnosol. Discussion: These results suggested that carnosol might ameliorate cancer cachexia-associated myotube atrophy by targeting P5CS and its downstream pathways.

VDAC1 Protein Regulation of Oxidative Damage and Mitochondrial Dysfunction-Mediated Cytotoxicity by Silica Nanoparticles in SH-SY5Y Cells

Silica nanoparticles (SiNPs) have been widely used in industry, electronics, and pharmaceutical industries. In addition, it is also widely used in medicine, tumor treatment and diagnosis, as well as other biomedical and biotechnology fields. The opportunities for people to contact SiNPs through iatrogenic, occupational, and environmental exposures are gradually increasing. The damage and biological effects of SiNPs on the nervous system have attracted widespread attention in the field of toxicology. Central nerve cells are rich in mitochondria. It is suggested that the effects of SiNPs on mitochondrial damage of nerve cells may involve the maintenance of neuronal membrane potential, the synthesis and operation of neurotransmitters, and the transmission of nerve pulses, and so on. We established an experimental model of SH-SY5Y cells to detect the cell survival rate, apoptosis, changes of reactive oxygen species and mitochondrial membrane potential, and the expression of mitochondrial function-related enzymes and proteins, so as to reveal the possible mechanism of SiNPs on neuronal mitochondrial damage. It was found that SiNPs could cause oxidative damage to cells and mitochondria, destroy some normal functions of mitochondria, and induce apoptosis in SH-SY5Y cells. The voltage-dependent anion channel 1(VDAC1) protein inhibitor DIDS could effectively reduce intracellular oxidative stress, such as the reduction of ROS content, and could also usefully restore some functional proteins of mitochondria to normal levels. The inhibition of VDAC1 protein may play an important role in the oxidative damage and dysfunction of neuronal mitochondria induced by SiNPs.

N6-methyladenosine RNA methylation in liver diseases: from mechanism to treatment

Epigenetic modification occurring in RNA has become the hotspot of the field. N6-methyladenosine (m6A) methylation is the most abundant RNA internal modification mainly occurring at the consensus motif DR (m6A) CH (D = A/G/U, R = A/G, H = A/C/U) in the 3'-UTR particularly the region near stop codons. The life cycle of m6A methylation includes "writers," "erasers," and "readers", which are responsible for the addition, removal, and recognition of m6A, respectively. m6A modification has been reported changing RNA secondary structure or modulating the stability, localization, transport, and translation of mRNAs to play crucial roles in various physiological and pathological conditions. Liver, as the largest metabolic and digestive organ, modulates vital physiological functions, and its dysfunction gives rise to the occurrence of various diseases. Despite the advanced intervening measures, mortality due to liver diseases is continuously high. Recent studies have explored the roles of m6A RNA methylation in the pathogenesis of liver diseases, providing new insights for studying the molecular mechanism of liver diseases. In the review, we extensively summarize the life cycle of m6A methylation, as well as its function and relevant mechanisms in liver fibrosis (LF), nonalcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), hepatitis virus infection, and hepatocellular carcinoma (HCC), and eventually we explore the potential of m6A as a treatment option for these liver diseases.

Carnosol inhibits cerebral ischemia-reperfusion injury by promoting AMPK activation

BACKGROUND

Carnosol is a phytopolyphenol (diterpene) found and extracted from plants of Mediterranean diet, which has anti-tumor, anti-inflammatory and antioxidant effects. However, its role in ischemic stroke has not been elucidated.

METHODS

Primary neurons subjected to oxygen-glucose deprivation (OGD) was used to investigate the effect of carnosol in vitro. A mouse MCAO model was used to evaluate the effect of carnosol on ischemic stroke in vivo. The mRNA level of inflammatory and apoptosis-related genes was determined by RT-PCR. The protein level of total and phosphorylated AMPK was determined by WB. H&E and Immunofluorescent assay was used to investigate the necrosis, inflammation and apoptosis in brain tissue.

RESULTS

Carnosol protected the activity of primary neurons subjected to oxygen-glucose deprivation (OGD) in vitro, as well as inhibited inflammation and apoptosis. Furthermore, carnosol could significantly reduce the infarct and edema volume and protect against neurological deficit in vivo, and had a significant inhibitory effect on brain neuroinflammation and apoptosis. Mechanically, carnosol could activate AMPK, and the effect of carnosol on cerebral ischemia-reperfusion injury cell model could be abolished by AMPK phosphorylation inhibitor.

CONCLUSION

Carnosol has a protective effect on ischemic stroke, and this effect is achieved through AMPK activation. Our study demonstrates the protective effect of carnosol on cerebral ischemia-reperfusion injury and provides a new perspective for the clinical treatment of ischemic stroke.

Protective Effects of Carnosol on Renal Interstitial Fibrosis in a Murine Model of Unilateral Ureteral Obstruction

Renal fibrosis is a common feature of chronic kidney disease and is a promising therapeutic target. However, there is still limited treatment for renal fibrosis, so the development of new anti-fibrotic agents is urgently needed. Accumulating evidence suggest that oxidative stress and endoplasmic reticulum (ER) stress play a critical role in renal fibrosis. Carnosol (CS) is a bioactive diterpene compound present in rosemary plants and has potent antioxidant and anti-inflammatory properties. In this study, we investigated the potential effects of CS on renal injury and fibrosis in a murine model of unilateral ureteral obstruction (UUO). Male C57BL/6J mice underwent sham or UUO surgery and received intraperitoneal injections of CS (50 mg/kg) daily for 8 consecutive days. CS improved renal function and ameliorated renal tubular injury and interstitial fibrosis in UUO mice. It suppressed oxidative injury by inhibiting pro-oxidant enzymes and activating antioxidant enzymes. Activation of ER stress was also attenuated by CS. In addition, CS inhibited apoptotic and necroptotic cell death in kidneys of UUO mice. Furthermore, cytokine production and immune cell infiltration were alleviated by CS. Taken together, these findings indicate that CS can attenuate renal injury and fibrosis in the UUO model.

Association between Dietary Pattern, Nutritional Status, Metabolic Factors, and Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) can be harmful to the body to varying degrees, and over a prolonged period, patients may develop steatotic cirrhosis or even develop liver cancer based on cirrhosis. Moreover, its harms are related to its severity. Patients with severe steatosis develop hepatocyte destruction, transaminase abnormalities, and long-term progression to steatotic cirrhosis, or even liver cancer, which should be treated aggressively. In order to provide theoretical basis for the prevention and early intervention of NAFLD, we analysis the relationship between nonalcoholic fatty liver disease(NAFLD) and dietary pattern, nutritional status, metabolic factor A total of 517 participants (200 males and 317 females) recruited in this study were gained from the health check center of The Ningbo Seventh Hospital, Ningbo, China, from September 2018 to August 2019. Patients diagnosed with NAFLD were selected as the study subjects. The data on the dietary pattern, nutritional status, and metabolic factors were collected for further analysis. A total of 517 eligible participants (317 females and 200 males) were involved in this study, with a mean age of 54.7 ± 16.7 years. Dessert and fruit diet, healthy dietary pattern, animal food dietary pattern, high salt diet mode, triglyceride, uric acid, adiponectin, and waist-hip ratio were significantly different between the two groups (P < 0.05). Dietary patterns, nutritional status, metabolic factors, and NAFLD are correlated. Furthermore, applying this correlation law can better manage NAFLD patients.

Mitochondrial Dysfunction and Chronic Liver Disease

Mitochondria are generally considered the powerhouse of the cell, a small subcellular organelle that produces most of the cellular energy in the form of adenosine triphosphate (ATP). In addition, mitochondria are involved in various biological functions, such as biosynthesis, lipid metabolism, oxidative phosphorylation, cell signal transduction, and apoptosis. Mitochondrial dysfunction is manifested in different aspects, like increased mitochondrial reactive oxygen species (ROS), mitochondrial DNA (mtDNA) damage, adenosine triphosphate (ATP) synthesis disorder, abnormal mitophagy, as well as changes in mitochondrial morphology and structure. Mitochondrial dysfunction is related to the occurrence and development of various chronic liver diseases, including hepatocellular carcinoma (HCC), viral hepatitis, drug-induced liver injury (DILI), alcoholic fatty liver (AFL), and non-alcoholic fatty liver (NAFL). In this review, we summarize and discuss the role and mechanisms of mitochondrial dysfunction in chronic liver disease, focusing on and discussing some of the latest studies on mitochondria and chronic liver disease.