Molecular Chaperonin HSP60: Current Understanding and Future Prospects.

Molecular chaperones are highly conserved across evolution and play a crucial role in preserving protein homeostasis. The 60 kDa heat shock protein (HSP60), also referred to as chaperonin 60 (Cpn60), resides within mitochondria and is involved in maintaining the organelle's proteome integrity and homeostasis. The HSP60 family, encompassing Cpn60, plays diverse roles in cellular processes, including protein folding, cell signaling, and managing high-temperature stress. In prokaryotes, HSP60 is well understood as a GroEL/GroES complex, which forms a double-ring cavity and aids in protein folding. In eukaryotes, HSP60 is implicated in numerous biological functions, like facilitating the folding of native proteins and influencing disease and development processes. Notably, research highlights its critical involvement in sustaining oxidative stress and preserving mitochondrial integrity. HSP60 perturbation results in the loss of the mitochondria integrity and activates apoptosis. Currently, numerous clinical investigations are in progress to explore targeting HSP60 both in vivo and in vitro across various disease models. These studies aim to enhance our comprehension of disease mechanisms and potentially harness HSP60 as a therapeutic target for various conditions, including cancer, inflammatory disorders, and neurodegenerative diseases. This review delves into the diverse functions of HSP60 in regulating proteo-homeostasis, oxidative stress, ROS, apoptosis, and its implications in diseases like cancer and neurodegeneration.

Gynostemma pentaphyllum Hydrodistillate and Its Major Component Damulin B Promote Hair Growth-Inducing Properties In Vivo and In Vitro via the Wnt/ß-Catenin Pathway in Dermal Papilla Cells.

Alopecia, a prevalent yet challenging condition with limited FDA-approved treatments which is accompanied by notable side effects, necessitates the exploration of natural alternatives. This study elucidated the hair growth properties of Gynostemma pentaphyllum leaf hydrodistillate (GPHD) both in vitro and in vivo. Furthermore, damulin B, a major component of GPHD, demonstrated hair growth-promoting properties in vitro. Beyond its established anti-diabetic, anti-obesity, and anti-inflammatory attributes, GPHD exhibited hair growth induction in mice parallel to minoxidil. Moreover, it upregulated the expression of autocrine factors associated with hair growth, including VEGF, IGF-1, KGF, and HGF. Biochemical assays revealed that minoxidil, GPHD, and damulin B induced hair growth via the Wnt/ß-catenin pathway through AKT signaling, aligning with in vivo experiments demonstrating improved expression of growth factors. These findings suggest that GPHD and damulin B contribute to the hair growth-inducing properties of dermal papilla cells through the AKT/ß-catenin signaling pathway.

Endoplasmic Reticulum Stress and Its Impact on Adipogenesis: Molecular Mechanisms Implicated.

Endoplasmic reticulum (ER) stress plays a pivotal role in adipogenesis, which encompasses the differentiation of adipocytes and lipid accumulation. Sustained ER stress has the potential to disrupt the signaling of the unfolded protein response (UPR), thereby influencing adipogenesis. This comprehensive review illuminates the molecular mechanisms that underpin the interplay between ER stress and adipogenesis. We delve into the dysregulation of UPR pathways, namely, IRE1-XBP1, PERK and ATF6 in relation to adipocyte differentiation, lipid metabolism, and tissue inflammation. Moreover, we scrutinize how ER stress impacts key adipogenic transcription factors such as proliferator-activated receptor γ (PPARγ) and CCAAT-enhancer-binding proteins (C/EBPs) along with their interaction with other signaling pathways. The cellular ramifications include alterations in lipid metabolism, dysregulation of adipokines, and aged adipose tissue inflammation. We also discuss the potential roles the molecular chaperones cyclophilin A and cyclophilin B play in adipogenesis. By shedding light on the intricate relationship between ER stress and adipogenesis, this review paves the way for devising innovative therapeutic interventions.

Gossypetin Prevents the Progression of Nonalcoholic Steatohepatitis by Regulating Oxidative Stress and AMP-Activated Protein Kinase.

Nonalcoholic steatohepatitis (NASH) is a severe liver metabolic disorder, however, there are still no effective and safe drugs for its treatment. Previous clinical trials used various therapeutic approaches to target individual pathologic mechanisms, but these approaches were unsuccessful because of the complex pathologic causes of NASH. Combinatory therapy in which two or more drugs are administered simultaneously to patients with NASH, however, carries the risk of side effects associated with each individual drug. To solve this problem, we identified gossypetin as an effective dual-targeting agent that activates AMP-activated protein kinase (AMPK) and decreases oxidative stress. Administration of gossypetin decreased hepatic steatosis, lobular inflammation and liver fibrosis in the liver tissue of mice with choline-deficient high-fat diet and methionine-choline deficient diet (MCD) diet-induced NASH. Gossypetin functioned directly as an antioxidant agent, decreasing hydrogen peroxide and palmitate-induced oxidative stress in the AML12 cells and liver tissue of MCD diet-fed mice without regulating the antioxidant response factors. In addition, gossypetin acted as a novel AMPK activator by binding to the allosteric drug and metabolite site, which stabilizes the activated structure of AMPK. Our findings demonstrate that gossypetin has the potential to serve as a novel therapeutic agent for nonalcoholic fatty liver disease /NASH. SIGNIFICANCE STATEMENT: This study demonstrates that gossypetin has preventive effect to progression of nonalcoholic steatohepatitis (NASH) as a novel AMP-activated protein kinase (AMPK) activator and antioxidants. Our findings indicate that simultaneous activation of AMPK and oxidative stress using gossypetin has the potential to serve as a novel therapeutic approach for nonalcoholic fatty liver disease /NASH patients.

Innate Immune System in the Pathogenesis of Non-Alcoholic Fatty Liver Disease.

Non-alcoholic fatty liver disease (NAFLD) is a prevalent condition characterized by lipid accumulation in hepatocytes with low alcohol consumption. The development of sterile inflammation, which occurs in response to a range of cellular stressors or injuries, has been identified as a major contributor to the pathogenesis of NAFLD. Recent studies of the pathogenesis of NAFLD reported the newly developed roles of damage-associated molecular patterns (DAMPs). These molecules activate pattern recognition receptors (PRRs), which are placed in the infiltrated neutrophils, dendritic cells, monocytes, or Kupffer cells. DAMPs cause the activation of PRRs, which triggers a number of immunological responses, including the generation of cytokines that promote inflammation and the localization of immune cells to the site of the damage. This review provides a comprehensive overview of the impact of DAMPs and PRRs on the development of NAFLD.

TOR1B: a predictor of bone metastasis in breast cancer patients.

Recent therapeutic advances in breast cancer (BC) have improved survival outcomes; however, the prognosis for patients with bone metastasis (BM) remains poor. Hence, novel clinical biomarkers are needed to accurately predict BC BM as well as to promote personalized medicine. Here, we discovered a novel biomarker, TOR1B, for BM in BC patients via analysis of BC gene expression data and clinical information downloaded from open public databases. In cancer cells, we found high expression levels of TOR1B in the nucleus and endoplasmic reticulum. Regarding gene expression, the level of TOR1B was significantly upregulated in BC patients with BM (p < 0.05), and the result was externally validated. In addition, gene expression clearly demonstrated two distinct types of prognoses in ER- and PR-positive patients. In multivariate regression, the gene could be an independent predictor of BM in BC patients, i.e., a low expression level of TOR1B was associated with delayed metastasis to bone in BC patients (HR, 0.28; 95% CI 0.094-0.84). Conclusively, TOR1B might be a useful biomarker for predicting BM; specifically, patients with ER- and PR-positive subtypes would benefit from the clinical use of this promising prognostic biomarker.

Cyclophilin B, a molecule chaperone, promotes adipogenesis in 3T3­L1 preadipocytes via AKT/mTOR pathway.

Cyclophilin is known to act as a molecular chaperone in the endoplasmic reticulum. Recent studies have reported that the expression of cyclophilin B (CypB) is increased in ob/ob mice and its inhibitor suppresses adipocyte differentiation. However, the mechanism of action of CypB in adipocytes remains to be elucidated. The present study investigated the role of CypB in 3T3­L1 adipocyte differentiation. It showed that the expression level of CypB was increased during 3T3­L1 adipocyte differentiation by reverse transcription­quantitative PCR and western blotting analysis. CypB knockdown using short interfering RNA delayed cell cycle progression from the G1/S to G2/M phase through the mammalian target of rapamycin (mTOR) signaling pathway and inhibited the expression levels of adipogenic transcription factors including peroxisome proliferator­activated receptor Î³ (PPARγ) and CCAAT­enhancer binding protein (C/EBP)α. Additionally, the accumulation of lipid droplets was inhibited by CypB knockdown. Conversely, overexpression of CypB promoted cell cycle progression from the G1/S to G2/M phase by the mTOR signaling pathway and enhanced the expression levels of adipogenic transcription factors including PPARγ and C/EBPα. Finally, the present study showed that CypB downregulated the expression of CHOP, a well­known negative regulator of adipogenesis. Taken together, the data suggested that CypB might serve important physiological regulatory roles in 3T3­L1 adipocyte differentiation.

A Hydrodistillate of Gynostemma pentaphyllum and Damulin B Prevent Cisplatin-Induced Nephrotoxicity In Vitro and In Vivo via Regulation of AMPKα1 Transcription.

The clinical application of cisplatin, one of the most effective chemotherapeutic agents used to treat various cancers, has been limited by the risk of adverse effects, notably nephrotoxicity. Despite intensive research for decades, there are no effective approaches for alleviating cisplatin nephrotoxicity. This study aimed to investigate the protective effects and potential mechanisms of a Gynostemma pentaphyllum leaves hydrodistillate (GPHD) and its major component, damulin B, against cisplatin-induced nephrotoxicity in vitro and in vivo. A hydro-distillation method can extract large amounts of components within a short period of time using non-toxic, environmentally friendly solvent. We found that the levels of AMP-activated protein kinase α1 (AMPKα1), reactive oxygen species (ROS), and apoptosis were tightly associated with each other in HEK293 cells treated with cisplatin. We demonstrated that AMPKα1 acted as an anti-oxidant factor and that ROS generated by cisplatin suppressed the expression of AMPKα1 at the transcriptional level, thereby resulting in induction of apoptosis. Treatment with GPHD or damulin B effectively prevented cisplatin-induced apoptosis of HEK293 cells and cisplatin-induced acute kidney injury in mice by suppressing oxidative stress and maintaining AMPKα1 levels. Therefore, our study suggests that GPHD and damulin B may serve as prospective adjuvant agents against cisplatin-induced nephrotoxicity.

Molecular Mechanisms for Ketone Body Metabolism, Signaling Functions, and Therapeutic Potential in Cancer.

The ketone bodies (KBs) ß-hydroxybutyrate and acetoacetate are important alternative energy sources for glucose during nutrient deprivation. KBs synthesized by hepatic ketogenesis are catabolized to acetyl-CoA through ketolysis in extrahepatic tissues, followed by the tricarboxylic acid cycle and electron transport chain for ATP production. Ketogenesis and ketolysis are regulated by the key rate-limiting enzymes, 3-hydroxy-3-methylglutaryl-CoA synthase 2 and succinyl-CoA:3-oxoacid-CoA transferase, respectively. KBs participate in various cellular processes as signaling molecules. KBs bind to G protein-coupled receptors. The most abundant KB, ß-hydroxybutyrate, regulates gene expression and other cellular functions by inducing post-translational modifications. KBs protect tissues by regulating inflammation and oxidative stress. Recently, interest in KBs has been increasing due to their potential for treatment of various diseases such as neurological and cardiovascular diseases and cancer. Cancer cells reprogram their metabolism to maintain rapid cell growth and proliferation. Dysregulation of KB metabolism also plays a role in tumorigenesis in various types of cancer. Targeting metabolic changes through dietary interventions, including fasting and ketogenic diets, has shown beneficial effects in cancer therapy. Here, we review current knowledge of the molecular mechanisms involved in the regulation of KB metabolism and cellular signaling functions, and the therapeutic potential of KBs and ketogenic diets in cancer.

Beta-naphthoflavone and doxorubicin synergistically enhance apoptosis in human lung cancer cells by inducing doxorubicin accumulation, mitochondrial ROS generation, and JNK pathway signaling.

Doxorubicin is one of the most effective chemotherapeutic agents available for treating various cancers, including lung cancer-the leading cause of cancer death in both men and women. However, its clinical application has been impeded by severe adverse effects, notably cardiotoxicity. Development of cellular resistance to doxorubicin is another major obstacle that must be overcome for broader application of the drug. In the present study, we examined the therapeutic potential of beta-naphthoflavone (BNF), a synthetic derivative of a naturally occurring flavonoid, in combination with doxorubicin for the treatment of lung cancer. Among our novel observations were that BNF enhances the efficacy of doxorubicin by inducing doxorubicin accumulation, mitochondrial ROS generation, and JNK pathway signaling in lung cancer cells. These combined effects were also evident in many other cancer cell types. BNF further exhibited synergistic induction of apoptosis in lung cancer cells when combined with several other cancer drugs, including irinotecan, cisplatin, and 5-fluorouracil. Our results suggest that BNF can be developed as a promising adjuvant agent for enhancing the efficacy of doxorubicin.

Recent Advances in Ovarian Cancer: Therapeutic Strategies, Potential Biomarkers, and Technological Improvements.

Aggressive and recurrent gynecological cancers are associated with worse prognosis and a lack of effective therapeutic response. Ovarian cancer (OC) patients are often diagnosed in advanced stages, when drug resistance, angiogenesis, relapse, and metastasis impact survival outcomes. Currently, surgical debulking, radiotherapy, and/or chemotherapy remain the mainstream treatment modalities; however, patients suffer unwanted side effects and drug resistance in the absence of targeted therapies. Hence, it is urgent to decipher the complex disease biology and identify potential biomarkers, which could greatly contribute to making an early diagnosis or predicting the response to specific therapies. This review aims to critically discuss the current therapeutic strategies for OC, novel drug-delivery systems, and potential biomarkers in the context of genetics and molecular research. It emphasizes how the understanding of disease biology is related to the advancement of technology, enabling the exploration of novel biomarkers that may be able to provide more accurate diagnosis and prognosis, which would effectively translate into targeted therapies, ultimately improving patients' overall survival and quality of life.

Correlation between Oxidative Stress and Transforming Growth Factor-Beta in Cancers.

The downregulation of reactive oxygen species (ROS) facilitates precancerous tumor development, even though increasing the level of ROS can promote metastasis. The transforming growth factor-beta (TGF-ß) signaling pathway plays an anti-tumorigenic role in the initial stages of cancer development but a pro-tumorigenic role in later stages that fosters cancer metastasis. TGF-ß can regulate the production of ROS unambiguously or downregulate antioxidant systems. ROS can influence TGF-ß signaling by enhancing its expression and activation. Thus, TGF-ß signaling and ROS might significantly coordinate cellular processes that cancer cells employ to expedite their malignancy. In cancer cells, interplay between oxidative stress and TGF-ß is critical for tumorigenesis and cancer progression. Thus, both TGF-ß and ROS can develop a robust relationship in cancer cells to augment their malignancy. This review focuses on the appropriate interpretation of this crosstalk between TGF-ß and oxidative stress in cancer, exposing new potential approaches in cancer biology.

Melatonin and doxorubicin synergistically enhance apoptosis via autophagy-dependent reduction of AMPKα1 transcription in human breast cancer cells.

Doxorubicin is one of the most effective agents used to treat various cancers, including breast cancer, but its usage is limited by the risk of adverse effects, including cardiotoxicity. Melatonin, a natural hormone that functions as a major regulator of circadian rhythms, has been considered a supplemental component for doxorubicin due to its potential to improve its effectiveness. However, the mechanisms and biological targets of the combination of melatonin and doxorubicin with respect to cancer cell death are not well understood. In the present study, we found that melatonin synergized with doxorubicin to induce apoptosis of breast cancer cells by decreasing the expression of AMP-activated protein kinase α1 (AMPK α1), which acts as a critical survival factor for cancer cells. This cotreatment-induced reduction in AMPKα1 expression occurred at the transcriptional level via an autophagy-dependent mechanism. The synergistic effects of the combined treatment were evident in many other cancer cell lines, and melatonin was also highly effective in inducing cancer death when combined with other cancer drugs, including cisplatin, 5-fluorouracil, irinotecan, and sorafenib. AMPKα1 expression was decreased in all of these cases, suggesting that reducing AMPKα1 can be considered an effective method to increase the sensitivity of cancer cells to doxorubicin treatment.

2-O-Methylhonokiol Suppresses HCV Replication via TRAF6-Mediated NF-kB Activation.

Hepatitis C virus (HCV) is associated with various liver diseases. Chronic HCV infection is characterized by an abnormal host immune response. Therefore, it is speculated that to suppress HCV, a well-regulated host immune response is necessary. 2-O-methylhonokiol was identified by the screening of anti-HCV compounds using Renilla luciferase assay in Huh 7.5/Con 1 genotype 1b replicon cells. Here, we investigated the mechanism by which 2-O-methylhonokiol treatment inhibits HCV replication using real-time PCR. Our data shows that treatment with 2-O-methylhonokiol activated innate immune responses via nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) pathway. Additionally, the immunoprecipitation result shows that treatment with 2-O-methylhonokiol augmented tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) by preventing p62 from binding to TRAF6, resulting in reduced autophagy caused by HCV. Finally, we reproduced our data with the conditioned media from 2-O-methylhonokiol-treated cells. These findings strongly suggest that 2-O-methylhonokiol enhances the host immune response and suppresses HCV replication via TRAF6-mediated NF-kB activation.

Honokiol inhibits hepatoma carcinoma cell migration through downregulated Cyclophilin B expression.

Hepatocellular carcinoma (HCC) is the fifth common types of cancer with poor prognosis in the world. Honokiol (HNK), a natural biphenyl compound derived from the magnolia plant, has been reported to exert anticancer effects, but its mechanism has not been elucidated exactly. In the present study, HNK treatment significantly suppressed the migration ability of HepG2 and Hep3B human hepatocellular carcinoma. The treatment reduced the expression levels of the genes associated with cell migration, such as S100A4, MMP-2, MMP-9 and Vimentin. Interestingly, treatment with HNK significantly reduced the expression level of Cyclophilin B (CypB) which stimulates cancer cell migration. However, overexpressed CypB abolished HNK-mediated suppression of cell migration, and reversed the apoptotic effects of HNK. Altogether, we concluded that the suppression of migration activities by HNK was through down-regulated CypB in HCC. These finding suggest that HNK may be a promising candidate for HCC treatment via regulation of CypB.

Melatonin prevents doxorubicin-induced cardiotoxicity through suppression of AMPKα2-dependent mitochondrial damage.

The clinical application of doxorubicin, one of the most effective anticancer drugs, has been limited due to its adverse effects, including cardiotoxicity. One of the hallmarks of doxorubicin-induced cytotoxicity is mitochondrial dysfunction. Despite intensive research over recent decades, there are no effective approaches for alleviating doxorubicin-induced cytotoxicity. Melatonin, a natural hormone that is primarily secreted by the pineal gland, is emerging as a promising adjuvant that protects against doxorubicin-induced cytotoxicity owing to its pharmaceutical effect of preserving mitochondrial integrity. However, the underlying mechanisms are far from completely understood. Here, we provide novel evidence that treatment of H9c2 cardiomyoblasts with doxorubicin strongly induced AMP-activated protein kinase α2 (AMPKα2), which translocated to mitochondria and interfered with their function and integrity, ultimately leading to cellular apoptosis. These phenomena were significantly blocked by melatonin treatment. The levels of AMPKα2 in murine hearts were tightly associated with cardiotoxicity in the context of doxorubicin and melatonin treatment. Therefore, our study suggests that the maintenance of mitochondrial integrity is a key factor in reducing doxorubicin-induced cytotoxicity and indicates that AMPKα2 may serve as a novel target in the design of cytoprotective combination therapies that include doxorubicin.

A 70-Gene Signature for Predicting Treatment Outcome in Advanced-Stage Cervical Cancer.

Cervical cancer is the fourth most common cancer in women worldwide. The current approaches still have limitations in predicting the therapy outcome of each individual because of cancer heterogeneity. The goal of this study was to establish a gene expression signature that could help when choosing the right therapeutic method for the treatment of advanced-stage cervical cancer. The 666 patients were collected from four independent datasets. The 70-gene expression signature was established using univariate Cox proportional hazard regression analysis. The 70-gene signature was significantly different between low- and high-risk groups in the training dataset (p = 4.24e-6) and in the combined three validation datasets (p = 4.37e-3). Treatment of advanced-stage cancer patients in the high-risk group with molecular-targeted therapy combined with chemoradiotherapy yielded a better survival rate than with only chemoradiotherapy (p = 0.0746). However, treatment of the patients in the low-risk group with the combined therapy resulted in significantly lower survival (p = 0.00283). Functional classification of 70 genes revealed involvement of the angiogenesis pathway, specifically phosphatidylinositol 3-kinase signaling (p = 0.040), extracellular matrix organization (p = 0.0452), and cell adhesion (p = 0.011). The 70-gene signature could predict the prognosis and indicate an optimal therapeutic modality in molecular-targeted therapy or chemotherapy for advanced-stage cervical cancer.