Antidiabetic adiponectin receptor agonist AdipoRon suppresses tumour growth of pancreatic cancer by inducing RIPK1/ERK-dependent necroptosis

The intricate role of adipokines in cancer-related signaling and the tumor microenvironment: Insights for future research

Obesity represents a global health challenge, with adipose tissue acting as a highly active endocrine organ that synthesizes and secretes a diverse array of bioactive proteins, known as adipokines. These cell signaling molecules regulate metabolic equilibrium, inflammatory cascades, and immune surveillance, exerting substantial systemic effects. A growing body of evidence has also highlighted their key role in cancer biology, through their intricate impact on oncogenic signaling networks and the tumor microenvironment (TME). The TME, a highly dynamic and heterotypic network composed of malignant cells, infiltrating immune cells, stromal constituents, and extracellular matrix elements, facilitates tumor evolution and immune evasion. Among adipokines, adiponectin and leptin have been extensively studied. Research has shown that adiponectin exhibits tumor-suppressive properties, whereas leptin enhances proliferative, angiogenic, and inflammatory pathways that promote malignancy. However, these effects are context-dependent and, at times, contradictory across different studies. Furthermore, the functional landscape of adipokines in cancer extends beyond these paradigms, with emerging research identifying a broader spectrum of novel adipokines involved in cancer reprogramming. This review delineates the molecular interplay between adipokines and oncogenic pathways, elucidating their mechanistic contributions to TME crosstalk and immune modulation. Additionally, we examine their potential as diagnostic and prognostic biomarkers and assess their viability as therapeutic targets for precision oncology. By integrating current evidence and identifying unresolved questions, this review aims to refine our understanding of adipokine-driven tumor biology and establish a platform for future research.

Combining AdipoRon with Paclitaxel Unveils Synergistic Potential in Non-Small Cell Lung Cancer Cells via AMPK-ERK1/2 Signaling

As part of chemotherapy regimens, Paclitaxel improves the overall survival of many non-small cell lung cancer (NSCLC) patients. However, the development of drug resistance and adverse events limits its clinical usage, reinforcing the need for further advancements in NSCLC therapeutics. We recently recognized the adiponectin receptor agonist AdipoRon as a promising anticancer compound in NSCLC. Consequently, this study aimed to evaluate the therapeutic potential of combining AdipoRon with Paclitaxel (Combo) in NSCLC cells. With respect to individual treatments, Combo triggered a stronger inhibition of both cell growth and clonogenic potential, as well as a greater induction of cell death. The Combo-mediated cytotoxicity was also corroborated by cleavage of poly-ADP ribose polymerase (PARP) and caspase-3 apoptotic markers. Notably, AMP-activated protein kinase (AMPK) emerged as a critical sensor in Combo efficacy, as its inhibition by Compound-C unveiled a significant rescue in cell growth. Although Combo caused a gradual downregulation of extracellular signal-regulated kinase 1/2 (ERK1/2), the hindrance in the upstream cascade by PD98059 partially counteracted the Combo outcomes. In conclusion, our findings designate AdipoRon as an effective candidate in Paclitaxel-based therapy. Nevertheless, future studies aimed at exploring the Combo aptitude in overcoming the Paclitaxel-related restraints need to be investigated in NSCLC.

Chemiluminescence Resonance Energy Transfer for Targeted Photoactivation of Ion Channels in Living Cells

The regulation of oxidative stress in living cells is essential for maintaining cellular processes and signal transduction. However, developing straightforward strategies to activate oxidative stress-sensitive membrane channels in situ poses significant challenges. In this study, we present a chemiluminescence resonance energy transfer (CRET) system based on a conjugated oligomer, oligo(p-phenylenevinylene)-imidazolium (OPV-Im), designed for the activation of transient receptor potential melastatin 2 (TRPM2) calcium channels in situ by superoxide anion (O2⋅-) without requiring external light sources. The OPV-Im oligomer targeted the cell membrane efficiently, leading to the activation of TRPM2 channels in situ by the CRET process and subsequent intracellular calcium overload. This cascade resulted in mitochondrial damage and inhibition of autophagy, ultimately inducing cell apoptosis. Additionally, this strategy could be applied for the selective killing of tumor cells that overexpress TRPM2 ion channels and for inhibiting the growth of three-dimensional (3D) tumor spheroids. Our system offers a novel approach for regulating ion channel activity and oxidative stress in living cells compared to optogenetics and photodynamic therapy.

The Role of Perirenal Adipose Tissue in Carcinogenesis-From Molecular Mechanism to Therapeutic Perspectives

Perirenal adipose tissue (PRAT) exhibits particular morphological features, with its activity being mainly related to thermogenesis. However, an expanded PRAT area seems to play a significant role in cardiovascular diseases, diabetes mellitus, and chronic kidney disease pathogenesis. Numerous studies have demonstrated that PRAT may support cancer progression and invasion, mainly in obese patients. The mechanism underlying these processes is of dysregulation of PRAT's secretion of adipokines and pro-inflammatory cytokines, such as leptin, adiponectin, chemerin, apelin, omentin-1, vistatin, nesfatin-1, and other pro-inflammatory cytokines, modulated by tumor cells. Cancer cells may also induce a metabolic reprogramming of perirenal adipocytes, leading to increased lipids and lactate transfer to the tumor microenvironment, contributing to cancer growth in a hypoxic milieu. In addition, the PRAT browning process has been specifically detected in renal cell carcinoma (RCC), being characterized by upregulated expression of brown/beige adipocytes markers (UCP1, PPAR-ɣ, c/EBPα, and PGC1α) and downregulated white fat cells markers, such as LEPTIN, SHOX2, HOXC8, and HOXC9. Considering its multifaceted role in cancer, modulation of PRAT's role in tumor progression may open new directions for oncologic therapy improvement. Considering the increasing evidence of the relationship between PRAT and tumor cells, our review aims to provide a comprehensive analysis of the perirenal adipocytes' impact on tumor progression and metastasis.

Suppression of necroptosis-driven cell death and inflammation in hypoxic neuroblastoma (SH-SY5Y) cells by necrostatin-1

Neuroblastoma (NB) is the most typical malignant extracranial solid tumor in the pediatric population. The advent of drug resistance is an essential deterrent in treating high-risk NB patients despite a multi-modality remedy. Inflammation-induced early neuronal degeneration plays a leading part in the pathogenesis of NB via necroptosis; however, the mechanisms remained cryptic. Our current investigation determines the anti-inflammatory and neuroprotective effect of necroptosis inhibitor necrostatin-1 (Nec-1) in receptor-interacting proteins 1 and 3 (RIP1/3)-induced cell death pathway and inflammation caused by hypoxia mimetic agent cobalt chloride (CoCl2). Our biomolecular study illustrates that necroptosis marker RIP1/3 and mixed-lineage kinase domain-like pseudokinase (MLKL) protein expression was increased after treatment with CoCl2 in SH-SY5Y cells. Subsequently, elevated expression levels of RIP1/3 and MLKL further contributed to the inflammation by activating transcription factors extracellular signal-regulated protein kinase (ERK1/2), nuclear factor kappa-B (NF-κB), and releasing high levels of proinflammatory cytokines, such as vascular endothelial growth factor (VEGF) and monocyte chemoattractant protein-1 (MCP-1/CCL2). At the same time, Nec-1 treatment reduced the RIP1/3 and MLKL, phospho-ERK1/2, p65 subunit of NF-κB expression, and VEGF and MCP-1 levels. Molecular docking analysis of RIP1/3-necrostatin-1 complex highlights a significant interaction between necrostatin-1 and specific amino acid residues within the protein. Based on our promising results, necrostatin-1 could be exploited as a therapeutic agent during neuroblastoma's pathogenesis and its molecular therapy.

The adipokines in oral cancer pathogenesis and its potential as a new therapeutic approach

The involvement of adipose tissue in the development of cancer is currently the subject of an increasing number of research due to the growing relevance of lipid metabolism in tumor growth. Obesity influences the tumor immune microenvironment (TME) in oral cancer. Visceral white adipose tissue (WAT) consists of adipocytes, connective tissue, immune cells, and stromovascular cells. The metabolic processes of immune cells within the adipose tissue of individuals with obesity predominantly depend on oxidative phosphorylation (intrinsically) and are characterized by elevated levels of M2 macrophages, Treg cells, Th2 cells, and eosinophils from an extrinsic perspective. The adipokines secreted by adipocytes facilitate communication with adjacent tissues to regulate glucose and lipid metabolism. Obesity influences cancer progression through the dysregulation of adipocytokines, characterized by an augmented synthesis of the oncogenic adipokine leptin, coupled with a reduced secretion of adiponectin. Under standard physiological settings, these adipokines fulfill essential roles in sustaining homeostasis. This review analyzed the influence of adipocytes on oral cancer by detailing the mediators released by adipocytes. Comprehending the molecular foundations of the protumor roles of adipokines in oral cancers might provide novel treatment targets.

Oral Administration of the Adiponectin Receptor 1 Agonistic Dipeptide Tyr-Pro Prevents Hyperglycemia in Spontaneously Diabetic Torii Rats

The dipeptide Tyr-Pro, a novel natural agonist of adiponectin receptor 1 (AdipoR1), promotes glucose uptake in skeletal muscle cells. This study investigated the antidiabetic effect of orally administered Tyr-Pro in spontaneously diabetic Torii (SDT) rats. Oral administration of Tyr-Pro (1 mg/kg/day) improved glucose intolerance in SDT rats at 22 weeks of prediabetic age. By 29 weeks of age, fasting blood glucose levels (BGLs) increased to 142 ± 14 mg/dL in the control group, whereas those in the Tyr-Pro group remained within the normal range (80-99 mg/dL), demonstrating a novel antidiabetic effect in vivo. Substantially increased levels of AdipoR1 and p-AMPK/AMPK were observed in the skeletal muscle of Tyr-Pro-administrated SDT rats. The intake of Tyr-Pro also enhanced insulin secretion and inhibited p-IRS-1(Ser) in skeletal muscle. These findings demonstrate that Tyr-Pro prevented the onset of diabetes and improved impaired insulin signaling pathways in SDT rats by inducing AdipoR1-mediated AMPK activation.

Synthesis, cytotoxicity, anti-inflammatory, anti-metastatic and anti-oxidant activities of novel chalcones incorporating 2-phenoxy-N-arylacetamide and thiophene moieties: induction of apoptosis in MCF7 and HEP2 cells

Eight Novel chalcones were synthesized and their structures were confirmed by different spectral tools. All the prepared compounds were subjected to SRB cytotoxic screening against several cancer cell lines. Compound 5c exerted the most promising effect against MCF7 and HEP2 cells with IC50 values of 9.5 and 12 µg/mL, respectively. Real-time PCR demonstrated the inhibitory effect of compound 5c on the expression level of Antigen kiel 67 (KI-67), Survivin, Interleukin-1beta (IL-1B), Interleukin-6 (IL-6), Cyclooxygenase-2 (COX-2) and Protein kinase B (AKT1) genes. Flow-cytometric analysis of the cell cycle indicated that compound 5c stopped the cell cycle at the G0/G1 and G2/M phases in MCF7 and HEP2 treated cells, respectively. ELISA assay showed that Caspase 8, Caspase 9, P53, BAX, and Glutathione (GSH) were extremely activated and Matrix metalloproteinase 2 (MMP2), Matrix metalloproteinase 9 (MMP9), BCL2, Malondialdehyde (MDA), and IL-6 were deactivated in 5c treated MCF7 and HEP2 cells. Wound healing revealed that chalcone 5c reduced the ability to close the scrape wound and decreased the number of migrating MCF7 and HEP2 cells compared to the untreated cells after 48 h. Theoretical molecular modeling against P53 cancer mutant Y220C and Bcl2 showed binding energies of -22.8 and -24.2 Kcal/mole, respectively, which confirmed our ELISA results.

Adiponectin receptor agonist AdipoRon alleviates memory impairment in the hippocampus of septic mice

Sepsis-associated encephalopathy (SAE) is a common and severe clinical feature of sepsis; however, therapeutic approaches are limited because of the unclear pathogenesis. Adiponectin receptor agonist (AdipoRon) is a small-molecule agonist of the adiponectin receptor that exhibits anti-inflammatory and memory-improving effects in various diseases. In the present study, we established lipopolysaccharide (LPS)-induced mice models of SAE and found that Adiponectin receptor 1 (AdipoR1) was significantly decreased in the hippocampus. Administration of AdipoRon improves memory impairment, mitigates synaptic damage, and alleviates neuronal death. Furthermore, AdipoRon reduces the number of microglia. More importantly, AdipoRon promotes the phosphorylation of adenosine 5 '-monophosphate activated protein kinase (pAMPK). In conclusion, AdipoRon is protective against SAE-induced memory decline and brain injury in the SAE models via activating the hippocampal adenosine 5 '-monophosphate activated protein kinase (AMPK).

Adiponectin Receptor Agonist AdipoRon Inhibits Proliferation and Drives Glycolytic Dependence in Non-Small-Cell Lung Cancer Cells

Despite the countless therapeutic advances achieved over the years, non-small-cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide. To this primacy contribute both non-oncogene addicted and advanced NSCLCs, in which conventional therapies are only partially effective. The adiponectin receptor agonist AdipoRon has revealed antiproliferative action in different cancers, including osteosarcoma and pancreatic cancer. Herein, we investigated its potential anticancer role in NSCLC for the first time. We proved that AdipoRon strongly inhibits viability, growth and colony formation in H1299 and A549 NSCLC cells, mainly through a slowdown in cell cycle progression. Along with the biological behaviors, a metabolic switching was observed after AdipoRon administration in NSCLC cells, consisting of higher glucose consumption and lactate accumulation. Remarkably, both 2-Deoxy Glucose and Oxamate glycolytic-interfering agents greatly enhanced AdipoRon's antiproliferative features. As a master regulator of cell metabolism, AMP-activated protein kinase (AMPK) was activated by AdipoRon. Notably, the ablation of AdipoRon-induced AMPK phosphorylation by Compound-C significantly counteracted its effectiveness. However, the engagement of other pathways should be investigated afterwards. With a focus on NSCLC, our findings further support the ability of AdipoRon in acting as an anticancer molecule, driving its endorsement as a future candidate in NSCLC therapy.

Identification of AdipoRon analogues as novel activators of AMPK for the treatment of type 2 diabetes

The activation of AMPK has emerged as a promising therapeutic approach for the treatment of metabolic diseases. AdipoRon, an agonist of the adiponectin receptor, has been identified as a compound capable of activating AMPK via the adiponectin receptor. To identify novel AdipoRon analogues with AMPK activation potential, a total of 17 analogues were designed, synthesized, and subjected to biological evaluation. Among these analogues, X-12 was discovered to exhibit potent activation of AMPK. In experimental studies, X-12 demonstrated dose-dependent improvements in glucose tolerance in normal mice. Furthermore, it significantly reduced fasting blood glucose levels and ameliorated insulin resistance in db/db diabetic mice. These findings highlight the therapeutic potential of X-12 as a novel class of AMPK activators for the treatment of metabolic diseases.

Adiponectin Receptor Agonist Effectively Suppresses Hepatocellular Carcinoma Growth

Hepatocellular carcinoma (HCC) is the second lethal cancer. Short overall survival, low five-year survival rate, and unimproved treatment efficacy urge the need to improve HCC prognosis. Adiponectin is key protector against cancer and hepatic abnormalities. Hypoadiponectinemia occurs in and promotes carcinogenesis and hepatic diseases. Adiponectin reactivation by different methods showed impressive effect against cancer and hepatic diseases. Recently, AdipoRon, an adiponectin receptor agonist, can interact with both Adiponectin receptors. AdipoRon showed promising anti-cancer effect in some cancers, but no study on HCC yet. The in vitro effect of AdipoRon on HCC was investigated by cell viability, migration, invasion, colony formation and apoptosis assays. The signalling alteration was determined by RT-qPCR and Western blot. The effect of treatment was interpreted by comparison between treatments and control. The difference between two cell lines was relatively compared. Our results showed significant in vitro anti-cancer effect of AdipoRon via AMPK- and dose-dependent manner. Huh7 cells showed a lower level of AdipoR1/2 and a superior proliferation and aggressiveness, compared to Hep3B. In addition, Huh7 cells were more sensitive to AdipoRon treatment (lower IC50, less cell growth, migration, invasion and colonies upon AdipoRon treatment) than Hep3B cells. In conclusion, AdipoRon effectively inhibited HCC growth and invasiveness in vitro. The deficient expression of adiponectin receptors affects efficacy of AdipoRon and aggressiveness of HCC cells.

Fundamental insights and molecular interactions in pancreatic cancer: Pathways to therapeutic approaches

The gastrointestinal tract can be affected by a number of diseases that pancreatic cancer (PC) is a malignant manifestation of them. The prognosis of PC patients is unfavorable and because of their diagnosis at advanced stage, the treatment of this tumor is problematic. Owing to low survival rate, there is much interest towards understanding the molecular profile of PC in an attempt in developing more effective therapeutics. The conventional therapeutics for PC include surgery, chemotherapy and radiotherapy as well as emerging immunotherapy. However, PC is still incurable and more effort should be performed. The molecular landscape of PC is an underlying factor involved in increase in progression of tumor cells. In the presence review, the newest advances in understanding the molecular and biological events in PC are discussed. The dysregulation of molecular pathways including AMPK, MAPK, STAT3, Wnt/β-catenin and non-coding RNA transcripts has been suggested as a factor in development of tumorigenesis in PC. Moreover, cell death mechanisms such as apoptosis, autophagy, ferroptosis and necroptosis demonstrate abnormal levels. The EMT and glycolysis in PC cells enhance to ensure their metastasis and proliferation. Furthermore, such abnormal changes have been used to develop corresponding pharmacological and nanotechnological therapeutics for PC.

The slow-release adiponectin analog ALY688-SR modifies early-stage disease development in the D2.mdx mouse model of Duchenne muscular dystrophy

Fibrosis is associated with respiratory and limb muscle atrophy in Duchenne muscular dystrophy (DMD). Current standard of care partially delays the progression of this myopathy but there remains an unmet need to develop additional therapies. Adiponectin receptor agonism has emerged as a possible therapeutic target to lower inflammation and improve metabolism in mdx mouse models of DMD but the degree to which fibrosis and atrophy are prevented remain unknown. Here, we demonstrate that the recently developed slow-release peptidomimetic adiponectin analog, ALY688-SR, remodels the diaphragm of murine model of DMD on DBA background (D2.mdx) mice treated from days 7-28 of age during early stages of disease. ALY688-SR also lowered interleukin-6 (IL-6) mRNA but increased IL-6 and transforming growth factor-β1 (TGF-β1) protein contents in diaphragm, suggesting dynamic inflammatory remodeling. ALY688-SR alleviated mitochondrial redox stress by decreasing complex I-stimulated H2O2 emission. Treatment also attenuated fibrosis, fiber type-specific atrophy, and in vitro diaphragm force production in diaphragm suggesting a complex relationship between adiponectin receptor activity, muscle remodeling, and force-generating properties during the very early stages of disease progression in murine model of DMD on DBA background (D2.mdx) mice. In tibialis anterior, the modest fibrosis at this young age was not altered by treatment, and atrophy was not apparent at this young age. These results demonstrate that short-term treatment of ALY688-SR in young D2.mdx mice partially prevents fibrosis and fiber type-specific atrophy and lowers force production in the more disease-apparent diaphragm in relation to lower mitochondrial redox stress and heterogeneous responses in certain inflammatory markers. These diverse muscle responses to adiponectin receptor agonism in early stages of DMD serve as a foundation for further mechanistic investigations.NEW & NOTEWORTHY There are limited therapies for the treatment of Duchenne muscular dystrophy. As fibrosis involves an accumulation of collagen that replaces muscle fibers, antifibrotics may help preserve muscle function. We report that the novel adiponectin receptor agonist ALY688-SR prevents fibrosis in the diaphragm of D2.mdx mice with short-term treatment early in disease progression. These responses were related to altered inflammation and mitochondrial functions and serve as a foundation for the development of this class of therapy.

Exploring the logic and conducting a comprehensive evaluation of AdipoRon-based adiponectin replacement therapy against hormone-related cancers-a systematic review

The potential benefits of adiponectin replacement therapy extend to numerous human diseases, with current research showing particular interest in its effectiveness against specific cancer forms, especially hormone-related. However, limitations in the pharmacological use of the intact protein have led to a focus on alternative options. AdipoRon is an extensively studied non-peptidic drug candidate for adiponectin replacement therapy. While researchers have explored the efficacy and therapeutic applications of AdipoRon in various disease conditions, their effects against cancer models advanced more, with no review regarding AdipoRon's efficacy against hormone-related cancers being published. The present systematic review aims to fill this gap. Preclinical evidence was compiled from PubMed, EMBASE, COCHRANE, and Google Scholar following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and the manuscript's quality assessment was conducted using the Joanna Briggs Institute (JBI) Checklist Critical Appraisal Tool for Systematic Reviews' Quality. The included nine studies incorporated various cell and animal models of the pancreas, gynaecological system, and osteosarcoma cancers. AdipoRon demonstrated effectiveness against pancreatic cancer by activating p44/42 MAPK, mitochondrial dysfunction, and AMPK-mediated inhibition of ACC1. In gynaecological cancers, it exhibited promising anticancer effects through the activation of AMPK, potential inhibition of mTOR, and modulation of the SET1B/BOD1/AdipoR1 signaling cascade. Against osteosarcoma, AdipoRon worked by perturbing ERK1/2 signaling and reducing p70S6K phosphorylation. AdipoRon shows promise in preclinical studies, but human trials are crucial for clinical safety and effectiveness. Caution is needed due to potential off-target effects, especially in cancer therapy with multi-target approaches. Structural biology and computational methods can help predict these effects.

Dysregulation of cellular membrane homeostasis as a crucial modulator of cancer risk

Cellular membranes serve as an epicentre combining extracellular and cytosolic components with membranous effectors, which together support numerous fundamental cellular signalling pathways that mediate biological responses. To execute their functions, membrane proteins, lipids and carbohydrates arrange, in a highly coordinated manner, into well-defined assemblies displaying diverse biological and biophysical characteristics that modulate several signalling events. The loss of membrane homeostasis can trigger oncogenic signalling. More recently, it has been documented that select membrane active dietaries (MADs) can reshape biological membranes and subsequently decrease cancer risk. In this review, we emphasize the significance of membrane domain structure, organization and their signalling functionalities as well as how loss of membrane homeostasis can steer aberrant signalling. Moreover, we describe in detail the complexities associated with the examination of these membrane domains and their association with cancer. Finally, we summarize the current literature on MADs and their effects on cellular membranes, including various mechanisms of dietary chemoprevention/interception and the functional links between nutritional bioactives, membrane homeostasis and cancer biology.

Utility of 2-Chloro-N-arylacetamide and 1,1'-(Piperazine-1,4-diyl)bis(2-chloroethanone) as Versatile Precursors for Novel Mono- and Bis[thienopyridines]

A series of novel thieno[2,3-b]pyridines linked to N-aryl carboxamides or (carbonylphenoxy)-N-(aryl)acetamides, as well as bis(thieno[2,3-b]pyridines) linked to piperazine core via methanone or carbonylphenoxyethanone units, were synthesized by treating the appropriate chloroacetyl- or bis-bromoacetyl derivatives with 2-mercaptonicotinonitrile derivatives in ethanolic sodium ethoxide at reflux. The spectral data were used to determine the compositions of novel compounds.

Application of calcium overload-based ion interference therapy in tumor treatment: strategies, outcomes, and prospects

Low selectivity and tumor drug resistance are the main hinderances to conventional radiotherapy and chemotherapy against tumor. Ion interference therapy is an innovative anti-tumor strategy that has been recently reported to induce metabolic disorders and inhibit proliferation of tumor cells by reordering bioactive ions within the tumor cells. Calcium cation (Ca2+) are indispensable for all physiological activities of cells. In particular, calcium overload, characterized by the abnormal intracellular Ca2+ accumulation, causes irreversible cell death. Consequently, calcium overload-based ion interference therapy has the potential to overcome resistance to traditional tumor treatment strategies and holds promise for clinical application. In this review, we 1) Summed up the current strategies employed in this therapy; 2) Described the outcome of tumor cell death resulting from this therapy; 3) Discussed its potential application in synergistic therapy with immunotherapy.

Antidiabetic features of AdipoAI, a novel AdipoR agonist

Adiponectin is an antidiabetic endogenous adipokine that plays a protective role against the unfavorable metabolic sequelae of obesity. Recent evidence suggests a sinister link between hypoadiponectinemia and development of insulin resistance/type 2 diabetes (T2D). Adiponectin's insulin-sensitizing property is mediated through the specific adiponectin receptors R1 and R2, which activate the AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor (PPAR) α pathways. AdipoAI is a novel synthetic analogue of endogenous adiponectin with possibly similar pharmacological effects. Thus, there is a need of orally active small molecules that activate Adipoq subunits, and their downstream signaling, which could ameliorate obesity related type 2 diabetes. In the study we aim to investigate the effects of AdipoAI on obesity and T2D. Through in-vitro and in-vivo analyses, we investigated the antidiabetic potentials of AdipoAI and compared it with AdipoRON, another orally active adiponectin receptors agonist. Our results showed that in-vitro treatment of AdipoAI (0-5 µM) increased adiponectin receptor subunits AdipoR1/R2 with increase in AMPK and APPL1 protein expression in C2C12 myotubes. Similarly, in-vivo, oral administration of AdipoAI (25 mg/kg) observed similar effects as that of AdipoRON (50 mg/kg) with improved control of blood glucose and insulin sensitivity in diet-induced obesity (DIO) mice models. Further, AdipoAI significantly reduced epididymal fat content with decrease in inflammatory markers and increase in PPAR-α and AMPK levels and exhibited hepatoprotective effects in liver. Further, AdipoAI and AdipoRON also observed similar results in adipose tissue. Thus, our results suggest that low doses of orally active small molecule agonist of adiponectin AdipoAI can be a promising therapeutic target for obesity and T2D.

AdipoRon and ADP355, adiponectin receptor agonists, in Metabolic-associated Fatty Liver Disease (MAFLD) and Nonalcoholic Steatohepatitis (NASH): A systematic review

Adiponectin replacement therapy holds the potential to benefit numerous human diseases, and ongoing research applies particular interest in how adiponectin acts against Metabolic-associated Fatty Liver Disease (MAFLD) and Nonalcoholic Steatohepatitis (NASH). However, the pharmacological limitations of the intact protein have prompted a focus on alternative options, specifically peptidic and small molecule agonists targeting the adiponectin receptor. AdipoRon is an extensively researched non-peptidic drug candidate in adiponectin replacement therapy. In turn, ADP355 is an adiponectin-based active short peptide. They have garnered significant attention due to their potential as substitutes for adiponectin. Researchers have studied AdipoRon's and ADP355's efficacy and therapeutic applications in various disease conditions. However, the effects of AdipoRon and ADP355 against NAFLD and NASH models advanced more, and no systematic review explored this area before. This systematic review was conceived to address the deficiency mentioned above and consider the lack of clinical evidence. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were utilized. To assess the risk of bias in systematic review, The Joanna Briggs Institute (JBI) Critical Appraisal Checklist was employed. Results from pre-clinical evidence show that AdipoRon and ADP355 represent promising effects in NAFLD and NASH-related models, including reducing hepatic steatosis, modulating inflammation, improving insulin sensitivity, enhancing mitochondrial function, and protecting against liver fibrosis. While AdipoRon and ADP355 exhibit promise in pre-clinical studies and experimental models, additional clinical trials are necessary to assess their effectiveness, safety, and potential translational therapeutic potential uses in NAFLD and NASH human cases.

The Effects of Adiponectin on the Behavior of B-Cell Leukemia Cells: Insights from an In Vitro Study

Background: Non-Hodgkin's lymphoma (NHL), the most frequent hematological neoplasm worldwide, represents a heterogeneous group of malignancies. The etiology of NHL remains to be fully elucidated, but the role of adipose tissue (AT) in immune function via the secretion of adipokines was recently recognized. Among adipokines, adiponectin has garnered attention for its beneficial properties. This study aimed to explore the in vitro effects of AdipoRon, an adiponectin agonist, on JVM-2, a lymphoblast cell line used as a representative disease model. Methods: JVM-2 cells were treated with different concentrations of AdipoRon to evaluate its effects on viability (via an MTT test), cell cycle distribution (via an FACS analysis), invasiveness (via a Matrigel assay) and colony-forming ability; protein expression was assessed via a real-time PCR (qPCR) and/or Western blotting (WB). Results: We found that the prolonged exposure of JVM-2 cells to AdipoRon led to a reduction in their viability due to a cytostatic effect. Additionally, AdipoRon stimulated both the formation of cell colonies and the expression of E-cadherin. Interestingly, the administration of AdipoRon increased the invasive potential of JVM-2 cells. Conclusions: Our findings indicate that adiponectin is involved in the regulation of different cellular processes of JVM-2 cells, supporting its potential association with a pro-tumorigenic phenotype and indicating that it might contribute to the increased aggressiveness and metastatic potential of B lymphoma cells. However, additional studies are required to fully understand the molecular mechanisms of adiponectin's actions on lymphoblasts and whether it may represent a marker of disease.

Role of Leptin and Adiponectin in Carcinogenesis

Hormones produced by adipocytes, leptin and adiponectin, are associated with the process of carcinogenesis. Both of these adipokines have well-proven oncologic potential and can affect many aspects of tumorigenesis, from initiation and primary tumor growth to metastatic progression. Involvement in the formation of cancer includes interactions with the tumor microenvironment and its components, such as tumor-associated macrophages, cancer-associated fibroblasts, extracellular matrix and matrix metalloproteinases. Furthermore, these adipokines participate in the epithelial-mesenchymal transition and connect to angiogenesis, which is critical for cancer invasiveness and cancer cell migration. In addition, an enormous amount of evidence has demonstrated that altered concentrations of these adipocyte-derived hormones and the expression of their receptors in tumors are associated with poor prognosis in various types of cancer. Therefore, leptin and adiponectin dysfunction play a prominent role in cancer and impact tumor invasion and metastasis in different ways. This review clearly and comprehensively summarizes the recent findings and presents the role of leptin and adiponectin in cancer initiation, promotion and progression, focusing on associations with the tumor microenvironment and its components as well as roles in the epithelial-mesenchymal transition and angiogenesis.

RIPK1 is aberrantly expressed in multiple B-cell cancers and implicated in the underlying pathogenesis

According to the latest epidemiology of the US, B-cell cancers account for > 3% of all new cancer cases and > 80% of non-Hodgkin lymphomas. However, the disease-modifying small molecular drug suitable for most B-cell cancers is still lacking. RIPK1 (receptor-interacting serine/threonine-protein kinase 1) has been observed to be dysregulated and implicated in the pathogenesis of multiple solid cancers, of which, however, the roles in blood cancers are quite unclear. In our study, to identify multi-function targets for B-cell cancer treatment, we reanalyzed a public transcriptomic dataset from the database of Gene Expression Omnibus, which includes CD19⁺ B-cell populations from 6 normal donors and patients of 5 CLL, 10 FL, and 8 DLBCL. After overlapping three groups (CLL vs. normal, FL vs. normal, and DLBCL vs. normal) of differentially expressed genes (DEGs), we obtained 69 common DEGs, of which 3 were validated by real-time quantitative PCR, including RIPK3, IGSF3, TGFBI. Interestingly, we found that the loss function of RIPK1 significantly increases the proliferation and viability of GM12878 cells (a normal human B lymphocyte cell line). Consistently, overexpression of RIPK1 in TMD8 and U2932 cells effectively inhibited cell proliferation and growth. More importantly, modifying RIPK1 kinase activity by a small molecule (such as necrostain-1, HOIPIN-1, etc.) alters the cell growth status of B-cell lymphoma, showing that RIPK1 exhibits anti-tumor activity in the context of B-cell lymphoma. Taken together, we consider that RIPK1 may be a potential target in the clinical application of B-cell lymphoma (including CLL, DLBCL, and FL) treatment.

Role of central Adiponectin and its interactions with NPY and GABAergic systems on food intake in neonatal layer chicken

BACKGROUND & AIM

Adiponectin is a member of the adipokine family and contributes to regulating energy homeostasis, reproduction, and various biological functions, such as insulin receptor signaling pathway sensitivity, mitochondrial biogenesis, oxidative metabolism, neurogenesis, and suppression of inflammation. This study aimed to investigate the effects of intracerebroventricular (ICV) injection of adiponectin and its interaction with the neuropeptide Y (NPY) and GABAergic systems on central appetite regulation in neonatal layer-type chickens.

MATERIALS & METHODS

In this study, 6 experiments were conducted, each of which included 4 experimental groups. In the first experiment, the chickens were injected with saline and adiponectin (20.73, 41.45, and 62.18 nmol). In the second experiment, saline, adiponectin (62.18 nmol), B5063 (NPY1 receptor antagonist, 2.12 nmol), and simultaneous injections of adiponectin and B5063 were performed. Experiments 3 to 6 were done in the same way to experiment 1, but the chickens were injected with SF22 (NPY2 receptor antagonist, 2.66 nmol), SML0891 (NPY5 receptor antagonist, 2.89 nmol), picrotoxin (GABAA receptor antagonist, 0.89 nmol), CGP54626 (GABAB receptor antagonist, 0.047 nmol) instead of B5063. Feed consumption was measured 120 min after the injection.

RESULTS

A dose-dependent increase in appetite was observed after the injection of adiponectin (20.73, 41.45, and 62.18 nmol) (P<0.05). The injection of B5063 + adiponectin attenuated the hyperphagic effect of adiponectin (P< 0.05). In addition, co-injection of picrotoxin and adiponectin significantly decreased adiponectin-induced hyperphagia (P<0.05). In addition, adiponectin significantly increased the number of steps, jumps, exploratory food, pecks, and standing time, while decreasing sitting time and rest time (P<0.05).

CONCLUSION

These results suggest that the hyperphagic effects of adiponectin are probably mediated through NPY1 and GABAA receptors in neonatal layer-type chickens.

Analysis of cuproptosis-related lncRNA signature for predicting prognosis and tumor immune microenvironment in pancreatic cancer

Pancreatic cancer (PC) is a highly malignant digestive tract tumor, with a dismal 5-year survival rate. Recently, cuproptosis was found to be copper-dependent cell death. This work aims to establish a cuproptosis-related lncRNA signature which could predict the prognosis of PC patients and help clinical decision-making. Firstly, cuproptosis-related lncRNAs were identified in the TCGA-PAAD database. Next, a cuproptosis-related lncRNA signature based on five lncRNAs was established. Besides, the ICGC cohort and our samples from 30 PC patients served as external validation groups to verify the predictive power of the risk signature. Then, the expression of CASC8 was verified in PC samples, scRNA-seq dataset CRA001160, and PC cell lines. The correlation between CASC8 and cuproptosis-related genes was validated by Real-Time PCR. Additionally, the roles of CASC8 in PC progression and immune microenvironment characterization were explored by loss-of-function assay. As showed in the results, the prognosis of patients with higher risk scores was prominently worse than that with lower risk scores. Real-Time PCR and single cell analysis suggested that CASC8 was highly expressed in pancreatic cancer and related to cuproptosis. Additionally, gene inhibition of CASC8 impacted the proliferation, apoptosis and migration of PC cells. Furthermore, CASC8 was demonstrated to impact the expression of CD274 and several chemokines, and serve as a key indicator in tumor immune microenvironment characterization. In conclusion, the cuproptosis-related lncRNA signature could provide valuable indications for the prognosis of PC patients, and CASC8 was a candidate biomarker for not only predicting the progression of PC patients but also their antitumor immune responses.

Mechanisms of obesity- and diabetes mellitus-related pancreatic carcinogenesis: a comprehensive and systematic review

Research on obesity- and diabetes mellitus (DM)-related carcinogenesis has expanded exponentially since these two diseases were recognized as important risk factors for cancers. The growing interest in this area is prominently actuated by the increasing obesity and DM prevalence, which is partially responsible for the slight but constant increase in pancreatic cancer (PC) occurrence. PC is a highly lethal malignancy characterized by its insidious symptoms, delayed diagnosis, and devastating prognosis. The intricate process of obesity and DM promoting pancreatic carcinogenesis involves their local impact on the pancreas and concurrent whole-body systemic changes that are suitable for cancer initiation. The main mechanisms involved in this process include the excessive accumulation of various nutrients and metabolites promoting carcinogenesis directly while also aggravating mutagenic and carcinogenic metabolic disorders by affecting multiple pathways. Detrimental alterations in gastrointestinal and sex hormone levels and microbiome dysfunction further compromise immunometabolic regulation and contribute to the establishment of an immunosuppressive tumor microenvironment (TME) for carcinogenesis, which can be exacerbated by several crucial pathophysiological processes and TME components, such as autophagy, endoplasmic reticulum stress, oxidative stress, epithelial-mesenchymal transition, and exosome secretion. This review provides a comprehensive and critical analysis of the immunometabolic mechanisms of obesity- and DM-related pancreatic carcinogenesis and dissects how metabolic disorders impair anticancer immunity and influence pathophysiological processes to favor cancer initiation.

A new approach: Evaluation of necroptosis and immune status enables prediction of the tumor microenvironment and treatment targets in pancreatic cancer

Growing evidence indicates a potential correlation between necroptosis and pancreatic cancer, and the relationship between necroptosis, immune infiltration and the microenvironment in pancreatic cancer has drawn increasing attention. However, two-dimensional phenotype and prognostic assessment systems based on a combination of necroptosis and immunity have not been explored. In our present study, we explored the pancancer genomics signature of necroptosis-related molecules, identifying necroptosis-related molecule mutation profiles, expression profiles, and correlations between expression levels and methylation/CNV levels. We identified distinct necroptotic as well as immune statuses in pancreatic cancer, and a high necroptosis phenotype and high immunity phenotype both indicated better prognosis than a low necroptosis phenotype and low immunity phenotype. The two-dimensional phenotype we constructed has ideal discriminative effects on pancreatic cancer prognosis, inflammation, and the immune microenvironment. The "high-necroptosis and high-immunity (HNHI)" group exhibited the best prognosis and the highest proportion of infiltrating immune cells. The NI score can be used to predict patient prognosis and is correlated with the immune microenvironment score, chemotherapeutic drug IC50, and tumor mutational burden. In addition, it may be useful for predicting the effect of individualized chemotherapy and immunotherapy. Our study also revealed that SLC2A1 is associated with both necroptosis and immunity and acts as a potential oncogene in pancreatic cancer. In conclusion, the two-dimensional phenotype and NI score we developed are promising tools for clinical multiomics applications and prediction of chemotherapy and immunotherapy response and present benefits in terms of precision medicine and individualized treatment decision-making for pancreatic cancer patients.

Obesity and main urologic cancers: Current systematic evidence, novel biological mechanisms, perspectives and challenges

Urologic cancers (UC) account for 13.1% of all new cancer cases and 7.9% of all cancer-related deaths. A growing body of evidence has indicated a potential causal link between obesity and UC. The aim of the present review is to appraise in a critical and integrative manner evidence from meta-analyses and mechanistic studies on the role of obesity in four prevalent UC (kidney-KC, prostate-PC, urinary bladder-UBC, and testicular cancer-TC). Special emphasis is given on Mendelian Randomization Studies (MRS) corroborating a genetic causal association between obesity and UC, as well as on the role of classical and novel adipocytokines. Furthermore, the molecular pathways that link obesity to the development and progression of these cancers are reviewed. Available evidence indicates that obesity confers increased risk for KC, UBC, and advanced PC (20-82%, 10-19%, and 6-14%, respectively), whereas for TC adult height (5-cm increase) may increase the risk by 13%. Obese females tend to be more susceptible to UBC and KC than obese males. MRS have shown that a higher genetic-predicted BMI may be causally linked to KC and UBC but not PC and TC. Biological mechanisms that are involved in the association between excess body weight and UC include the Insulin-like Growth Factor axis, altered availability of sex hormones, chronic inflammation and oxidative stress, abnormal secretion of adipocytokines, ectopic fat deposition, dysbiosis of the gastrointestinal and urinary tract microbiomes and circadian rhythm dysregulation. Anti-hyperglycemic and non-steroidal anti-inflammatory drugs, statins, and adipokine receptor agonists/antagonists show potential as adjuvant cancer therapies. Identifying obesity as a modifiable risk factor for UC may have significant public health implications, allowing clinicians to tailor individualized prevention strategies for patients with excess body weight.

Obesity and endocrine-related cancer: The important role of IGF-1

Obesity is increasingly becoming a global epidemic of concern and is considered a risk factor for several endocrine-related cancers. Moreover, obesity is associated with cancer development and poor prognosis. As a metabolic abnormality, obesity leads to a series of changes in insulin, IGF-1, sex hormones, IGFBPs, and adipokines. Among these factors, IGF-1 plays an important role in obesity-related endocrine cancers. This review describes the role of obesity in endocrine-related cancers, such as prostate cancer, breast cancer and pancreatic cancer, focusing on the mechanism of IGF-1 and the crosstalk with estrogen and adipokines. In addition, this review briefly introduces the current status of IGF-1R inhibitors in clinical practice and shows the prospect of IGF-1R inhibitors in combination with other anticancer drugs.

Targeting Adiponectin in Breast Cancer

Obesity and breast cancer are two major health issues that could be categorized as sincere threats to human health. In the last few decades, the relationship between obesity and cancer has been well established and extensively investigated. There is strong evidence that overweight and obesity increase the risk of postmenopausal breast cancer, and adipokines are the central players in this relationship. Produced and secreted predominantly by white adipose tissue, adiponectin is a bioactive molecule that exhibits numerous protective effects and is considered the guardian angel of adipokine. In the obesity-cancer relationship, more and more evidence shows that adiponectin may prevent and protect individuals from developing breast cancer. Recently, several updates have been published on the implication of adiponectin in regulating tumor development, progression, and metastases. In this review, we provide an updated overview of the metabolic signaling linking adiponectin and breast cancer in all its stages. On the other hand, we critically summarize all the available promising candidates that may reactivate these pathways mainly by targeting adiponectin receptors. These molecules could be synthetic small molecules or plant-based proteins. Interestingly, the advances in genomics have made it possible to create peptide sequences that could specifically replace human adiponectin, activate its receptor, and mimic its function. Thus, the obvious anti-cancer activity of adiponectin on breast cancer should be better exploited, and adiponectin must be regarded as a serious biomarker that should be targeted in order to confront this threatening disease.

Necroptosis pathways in tumorigenesis

Necroptosis is a caspase-independent form of programmed cell death executed by the receptor interacting protein kinase 1 (RIPK1)-RIPK3-mixed lineage kinase domain-like protein (MLKL) signaling cascade, deregulation of which can cause various human diseases including cancer. Escape from programmed cell death is a hallmark of cancer, leading to uncontrolled growth and drug resistance. Therefore, it is crucial to further understand whether necroptosis plays a key role in therapeutic resistance. In this review, we summarize the recent findings of the link between necroptosis and cancer, and discuss that targeting necroptosis is a new strategy to overcome apoptosis resistance in tumor therapy.

Adiponectin Suppresses Metastasis of Nasopharyngeal Carcinoma through Blocking the Activation of NF-κB and STAT3 Signaling

Adiponectin is an adipocytokine with anti-inflammatory and anticancer properties. Our previous study has shown that blood adiponectin levels were inversely correlated to the risk of nasopharyngeal carcinoma (NPC), and that adiponectin could directly suppress the proliferation of NPC cells. However, the effect of adiponectin on NPC metastasis remains unknown. Here, we revealed in clinical studies that serum adiponectin level was inversely correlated with tumor stage, recurrence, and metastasis in NPC patients, and that low serum adiponectin level also correlates with poor metastasis-free survival. Coculture with recombinant adiponectin suppressed the migration and invasion of NPC cells as well as epithelial-mesenchymal transition (EMT). In addition, recombinant adiponectin dampened the activation of NF-κB and STAT3 signaling pathways induced by adipocyte-derived proinflammatory factors such as leptin, IL-6, and TNF-α. Pharmacological activation of adiponectin receptor through its specific agonist, AdipoRon, largely stalled the metastasis of NPC cells. Taken together, these findings demonstrated that adiponectin could not only regulate metabolism and inhibit cancer growth, but also suppress the metastasis of NPC. Pharmacological activation of adiponectin receptor may be a promising therapeutic strategy to stall NPC metastasis and extend patients' survival.

A panel of necroptosis-related genes predicts the prognosis of pancreatic adenocarcinoma

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The 5-NRGs signature can predict the prognosis of pancreatic adenocarcinoma.

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The 5-NRGs signature reflects the immune landscape of pancreatic adenocarcinoma.

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The 5-NRGs can be detected in exosomes of serum using RT-qPCR method.

Pancreatic adenocarcinoma (PAAD) has become one of the deadliest malignancies in the world. Since necroptosis plays a crucial role in regulating the immune system, it is necessary to develop novel prognostic biomarkers associated with necroptosis and explore its potential role in PAAD. The transcriptome RNA-seq data of PAAD were downloaded from the TCGA and GTEx databases. A prognostic signature was constructed by the least absolute shrinkage and selection operator (LASSO) Cox regression, and its prognostic value was evaluated by nomogram and validated in an independent GEO cohort. We identified a total of 24 differentially expressed NRGs in PAAD, and constructed a prognostic signature with 5 NRGs, which showed good performance in predicting the prognosis of PAAD patients. The ROC curves for 1-, 3-, and 5-year survival rate were 0.652, 0.778, and 0.817, respectively. This prognostic signature showed consistent prognosis prediction in an independent patient cohort. Furthermore, the correlations between 5-NRGs signature and TMB, MSI, histopathological classification, immune infiltration, immune types, and immunomodulators were all significant. Notably, the expression profiles of the five NRGs in exosomes of serum were consistent with their expression in tumor tissues. These data suggested that the 5-NRGs signature is a promising biomarker for predicting the prognosis of PAAD.

In Vitro and in Silico Analyses of the Adiponectin Receptor Agonistic Action of Soybean Tripeptides

The Tyr-Pro (YP) dipeptide can serve as an adiponectin receptor 1 (AdipoR1) agonist. We thus investigated the AdipoR1-agonistic potential of YP-related tripeptides in the soybean protein sequence. Among the 17 soybean candidate tripeptides, those elongated at the C-terminus of YP (0.1 μM YPG, 140 ± 16%; 0.1 μM YPE, 141 ± 22%; 0.1 μM YPP, 145 ± 19%; 0.1 μM YPQ, 143 ± 20%; p < 0.05) significantly promoted glucose uptake by L6 muscle myotubes, comparable to the effect of 0.1 μM AdipoRon (163 ± 52%, p < 0.05). The knockdown of AdipoR1 expression in L6 cells abrogated this effect of YPG and YPP, indicating that the two tripeptides had an AdipoR1 agonistic effect. CHARMM-GUI-aided molecular dynamics simulation in a virtual phospholipid membrane revealed that YPG and YPP were stably positioned at the binding pockets of AdipoR1 (binding free energy < -10 kcal/mol). These findings demonstrate that the tripeptides YPG and YPP, with AdipoR1 agonistic YP sequences, have alternative adiponectin-like potential via their preferential binding to AdipoR1.

AdipoRon and Pancreatic Ductal Adenocarcinoma: a future perspective in overcoming chemotherapy-induced resistance?

The latest scientific knowledge has provided additional insights accountable for the worst prognosis for pancreatic ductal adenocarcinoma (PDAC). Among the causative factors, the aptitude to develop resistance towards approved medications denotes the master key for understanding the lack of improvement in PDAC survival over the years. Even though several compounds have achieved encouraging results at preclinical stage, no new adjuvant agents have reached the bedside of PDAC patients lately. The adiponectin receptor agonist AdipoRon is emerging as a promising anticancer drug in different cancer models, particularly in PDAC. Building on the existing findings, we recently reinforced its candidacy in PDAC cells, proposing AdipoRon either as a suitable partner in gemcitabine-based treatment or as an effective drug in resistant cells. Crossing the current state-of-the-art, herein we provide a critical perspective on AdipoRon to figure out whether this receptor agonist can potentially be considered a future therapeutic choice in overcoming chemotherapy-induced resistance, expressly in PDAC.

Understanding Necroptosis in Pancreatic Diseases

Intermediate between apoptosis and necrosis, necroptosis is a regulated caspase-independent programmed cell death that induces an inflammatory response and mediates cancer development. As our understanding improves, its role in the physiopathology of numerous diseases, including pancreatic diseases, has been reconsidered, and especially in pancreatitis and pancreatic cancer. However, the exact pathogenesis remains elusive, even though some studies have been conducted on these diseases. Its unique mechanisms of action in diseases are expected to bring prospects for the treatment of pancreatic diseases. Therefore, it is imperative to further explore its molecular mechanism in pancreatic diseases in order to identify novel therapeutic options. This article introduces recent related research on necroptosis and pancreatic diseases, explores necroptosis-related molecular pathways, and provides a theoretical foundation for new therapeutic targets for pancreatic diseases.

Distribution of Adiponectin Receptors in the Brain of Adult Mouse: Effect of a Single Dose of the Adiponectin Receptor Agonist, AdipoRON, on Ischemic Stroke

Adiponectin exhibits pleiotropic effects, including anti-inflammatory, anti-apoptotic, anti-oxidant, and neuroprotective ones. Although some studies have documented brain expression in different rodent models of its receptors, AdipoR1 and AdipoR2, their global distribution remains incomplete. Here, we demonstrated that both AdipoR are widely distributed in the brains of adult mice. Furthermore, by double immunostaining studies, we showed that AdipoR1 and AdipoR2 are mainly expressed in neurons and blood vessels. Then, considering the wide distribution of both receptors and the neuroprotective effects of adiponectin, we tested the therapeutic effect of a single injection of the adiponectin receptor agonist, AdipoRON (5 mg.kg⁻¹), 24 h after stroke in a model of middle cerebral artery occlusion technique (MCAO). Under our experimental conditions, we demonstrated that AdipoRON did not modulate the infarct volume, cell death, neuroinflammatory parameters including microglia activation and oxidative stress. This study suggests that a protocol based on multiple injections of AdipoRON at a higher dose after MCAO could be considered to promote the therapeutic properties of AdipoRON on the brain repair mechanism and recovery.

The Role of Nonapoptotic Programmed Cell Death — Ferroptosis, Necroptosis, and Pyroptosis — in Pancreatic Ductal Adenocarcinoma Treatment

Pancreatic ductal adenocarcinoma (PDAC) is the most lethal cancer, with a dismal 5-year survival rate of less than 10%. It is estimated that approximately 80% of pancreatic ductal carcinoma (PDAC) patients are diagnosed at an advanced or metastatic stage. Hence, most patients are not appropriate candidates for surgical resection and therefore require systemic chemotherapy. However, it has been reported that most patients develop chemoresistance within several months, partly because of antiapoptotic mechanisms. Hence, inducing alternative programmed cell death (PCD), including ferroptosis, necroptosis or pyroptosis, seems to be a promising strategy to overcome antiapoptosis-mediated chemoresistance. In this review, we shed light on the molecular mechanisms of ferroptosis, necroptosis and pyroptosis and suggest several potential strategies (e.g., compounds and nanoparticles [NPs]) that are capable of triggering nonapoptotic PCD to suppress PDAC progression. In conclusion, these strategies might serve as adjuvants in combination with clinical first-line chemotherapies to improve patient survival rates.

Integrating Gemcitabine-Based Therapy With AdipoRon Enhances Growth Inhibition in Human PDAC Cell Lines

Pancreatic ductal adenocarcinoma (PDAC) accounts for 90% of all pancreatic cancers. Albeit its incidence does not score among the highest in cancer, PDAC prognosis is tremendously fatal. As a result of either aggressiveness or metastatic stage at diagnosis, chemotherapy constitutes the only marginally effective therapeutic approach. As gemcitabine (Gem) is still the cornerstone for PDAC management, the low response rate and the onset of resistant mechanisms claim for additional therapeutic strategies. The first synthetic orally active adiponectin receptor agonist AdipoRon (AdipoR) has recently been proposed as an anticancer agent in several tumors, including PDAC. To further address the AdipoR therapeutic potential, herein we investigated its pharmacodynamic interaction with Gem in human PDAC cell lines. Surprisingly, their simultaneous administration revealed a more effective action in contrasting PDAC cell growth and limiting clonogenic potential than single ones. Moreover, the combination AdipoR plus Gem persisted in being effective even in Gem-resistant MIA PaCa-2 cells. While a different ability in braking cell cycle progression between AdipoR and Gem supported their cooperating features in PDAC, mechanistically, PD98059-mediated p44/42 MAPK ablation hindered combination effectiveness. Taken together, our findings propose AdipoR as a suitable partner in Gem-based therapy and recognize the p44/42 MAPK pathway as potentially involved in combination outcomes.

Adiponectin suppresses tumor growth of nasopharyngeal carcinoma through activating AMPK signaling pathway

BACKGROUND

Adiponectin is an adipocyte-secreted cytokine that enhances insulin sensitivity and attenuates inflammation. Although circulating adiponectin level is often inversely associated with several malignancies, its role in the development of nasopharyngeal carcinoma (NPC) remains unclear. Here, we investigated the clinical association between circulating adiponectin level and NPC, and examined the impact of adiponectin, as well as the underlying mechanisms, on NPC growth both in vitro and in vivo.

METHODS

The association between circulating adiponectin level and the risk of developing NPC was assessed in two different cohorts, including a hospital-based case-control study with 152 cases and 132 controls, and a nested case-control study with 71 cases and 142 controls within a community-based NPC screening cohort. Tumor xenograft model, cell proliferation and cycle assays were applied to confirm the effects of adiponectin on NPC growth in cultured cells and in xenograft models. We also investigated the underlying signaling mechanisms with various specific pharmacological inhibitors and biochemistry analysis.

RESULTS

High adiponectin levels were associated with a monotonic decreased trend of NPC risk among males in both the hospital-based case-control study and a nested case-control study. In vitro, recombinant human full-length adiponectin significantly inhibited NPC cell growth and arrested cell cycle, which were dependent on AMPK signaling pathway. The growth of xenograft of NPC tumor was sharply accelerated in the nude mice carrying genetic adiponectin deficiency. An adiponectin receptor agonist, AdipoRon, displayed strong anti-tumor activity in human xenograft models.

CONCLUSIONS

These findings demonstrated for the first time that circulating adiponectin is not only inversely associated with NPC, but also controls the development of NPC via AMPK signaling pathway. Stimulation of adiponectin function may become a novel therapeutic modality for NPC.

Synthetic adiponectin-receptor agonist, AdipoRon, induces glycolytic dependence in pancreatic cancer cells

Obesity creates a localized inflammatory reaction in the adipose, altering secretion of adipocyte-derived factors that contribute to pathologies including cancer. We have previously shown that adiponectin inhibits pancreatic cancer by antagonizing leptin-induced STAT3 activation. Yet, the effects of adiponectin on pancreatic cancer cell metabolism have not been addressed. In these studies, we have uncovered a novel metabolic function for the synthetic adiponectin-receptor agonist, AdipoRon. Treatment of PDAC cells with AdipoRon led to mitochondrial uncoupling and loss of ATP production. Concomitantly, AdipoRon-treated cells increased glucose uptake and utilization. This metabolic switch further correlated with AMPK mediated inhibition of the prolipogenic factor acetyl coenzyme A carboxylase 1 (ACC1), which is known to initiate fatty acid catabolism. Yet, measurements of fatty acid oxidation failed to detect any alteration in response to AdipoRon treatment, suggesting a deficiency for compensation. Additional disruption of glycolytic dependence, using either a glycolysis inhibitor or low-glucose conditions, demonstrated an impairment of growth and survival of all pancreatic cancer cell lines tested. Collectively, these studies provide evidence that pancreatic cancer cells utilize metabolic plasticity to upregulate glycolysis in order to adapt to suppression of oxidative phosphorylation in the presence of AdipoRon.

Diacerein versus adipoRon as adiponectin modulators in experimentally-induced end-stage type 2 diabetes mellitus in rats

The objective of the present study is to evaluate and compare the possible anti-diabetic effects of adipoRon and diacerein in type 2 diabetes mellitus (T2DM) rats. T2DM is marked by impaired oxidative, inflammatory and metabolic signaling. Indeed, T2DM progression is associated with elevated HbA1C%, low adiponectin and insulin concentration. Moreover, in this study epididymal adipose tissue and soleus muscle MDA contents significantly escalated, while serum TAC and epididymal adipose Nrf2 significantly declined. Nevertheless, serum TNF-α, epididymal NLRP3, NF-κB, PPARγ and CD68 expression rose significantly with a parallel significant reduction in serum IL-10 and soleus muscle expression of IRS1. Both adipoRon and diacerein significantly improved adiponectin and insulin secretion with augmentation of anti-oxidant defenses and diminution of oxidative burden, with obvious anti-inflammatory consequences (p < 0.05). Thus, adipoRon and diacerein positively modulated adiponectin expression with down-regulation of NF-κB/NLRP3/PPARγ expression with subsequent improvement in glycemic control, inflammatory and oxidative signaling.

Nanoplatform-mediated calcium overload for cancer therapy

Mitochondria, as the "the plant of power" of cells, have been extensively highlighted with biological functions of offering energy and participating in signaling pathways. In parallel, calcium (Ca2+) plays a...

New Antagonists of the Membrane Androgen Receptor OXER1 from the ZINC Natural Product Database

OXER1 (oxoeicosanoid receptor 1) was deorphanized in 1993 and found to be the specific receptor for the arachidonic acid metabolite 5-oxo-ETE. Recently, we have reported that androgen binds to this receptor also, being a membrane androgen receptor, triggering a number of its membrane-mediated actions (cell migration, apoptosis, cell proliferation, Ca²⁺ movements). In addition, our previous work suggested that a number of natural monomeric and oligomeric polyphenols interact with OXER1, acting similar to testosterone. Here, we interrogated the natural product chemical space and identified nine polyphenolic molecules with interesting in silico pharmacological activities as putative OXER1 antagonists. The molecule with the best pharmacokinetic-pharmacodynamic properties (ZINC15959779) was purchased and tested on OXER1, in prostate cancer cell cultures. It showed that it has actions similar to those of testosterone in inhibiting cAMP, while it had no action in intracellular Ca²⁺ mobilization or actin cytoskeleton rearrangement/migration. These results are discussed under the prism of structure-activity relationships and in silico models of the OXER1 binding groove. We suggest that these compounds, together with the previously reported (poly)phenolic compounds, can be lead structures for the exploration of the anti-inflammatory and antiproliferative effects of OXER1 antagonists.

Chlorpyrifos caused necroptosis via MAPK/NF-κB/TNF-α pathway in common carp (Cyprinus carpio L.) gills

Chlorpyrifos (CPF) is an organophosphate insecticide and can cause cell death of animals. In the study, the common carp were exposed to CPF at 0 μg/L (the control group), 1.16 μg/L (the low dose group), 11.6 μg/L (the medium dose group), and 116 μg/L (the high dose group), respectively. The carp were euthanized at the 30th day and gills were collected immediately. The ultrastructural and histopathological observations showed obvious necrosis characteristics and inflammatory injury in the CPF-treated groups. CPF exposure activated the MAPK pathway, in which the mRNA and protein expressions of extracellular signal-regulated (ERK), p38 MAP kinase (p38), and c-Jun N-terminal kinase (JNK) were increased; the mRNAs and proteins of NF-κB and TNF-α were activated; and the mRNAs and proteins of necroptosis related genes were changed (the mRNA and protein expression of RIPK1, RIPK3, MLKL, and FADD were increased and caspase-8 was decreased) with concentration dependency. Taken together, we concluded that CPF exposure activated the MAPK/NF-κB/TNF-α pathway, promoted inflammatory injure and evoked necroptosis in common carp gills. In addition, CPF-induced inflammation and necroptosis was concentration dependency. The toxic effects of CPF on gills provided data for both aquaculture and toxicological studies.

Cell death in pancreatic cancer: from pathogenesis to therapy

Pancreatic cancer is a devastating gastrointestinal cancer characterized by late diagnosis, limited treatment success and dismal prognosis. Exocrine tumours account for 95% of pancreatic cancers and the most common pathological type is pancreatic ductal adenocarcinoma (PDAC). The occurrence and progression of PDAC involve multiple factors, including internal genetic alterations and external inflammatory stimuli. The biology and therapeutic response of PDAC are further shaped by various forms of regulated cell death, such as apoptosis, necroptosis, ferroptosis, pyroptosis and alkaliptosis. Cell death induced by local or systemic treatments suppresses tumour proliferation, invasion and metastasis. However, unrestricted cell death or tissue damage might result in an inflammation-related immunosuppressive microenvironment, which is conducive to tumour progression or recurrence. The precise extent to which cell death affects PDAC is not yet well described. A growing body of preclinical and clinical studies document significant correlations between mutations (for example, in KRAS and TP53), stress responses (such as hypoxia and autophagy), metabolic reprogramming and chemotherapeutic responses. Here, we describe the molecular machinery of cell death, discuss the complexity and multifaceted nature of lethal signalling in PDAC cells, and highlight the challenges and opportunities for activating cell death pathways through precision oncology treatments.

Obesity and Pancreatic Cancer: Insight into Mechanisms

Simple Summary

Obesity is recognized as a chronic progressive disease and risk factor for many human diseases. The high and increasing number of obese people may underlie the expected increase in pancreatic cancer cases in the United States. There are several pathways discussed that link obesity with pancreatic cancer. Adipose tissue and adipose tissue-released factors may thereby play an important role. This review discusses selected mechanisms that may accelerate pancreatic cancer development in obesity.

Abstract

The prevalence of obesity in adults and children has dramatically increased over the past decades. Obesity has been declared a chronic progressive disease and is a risk factor for a number of metabolic, inflammatory, and neoplastic diseases. There is clear epidemiologic and preclinical evidence that obesity is a risk factor for pancreatic cancer. Among various potential mechanisms linking obesity with pancreatic cancer, the adipose tissue and obesity-associated adipose tissue inflammation play a central role. The current review discusses selected topics and mechanisms that attracted recent interest and that may underlie the promoting effects of obesity in pancreatic cancer. These topics include the impact of obesity on KRAS activity, the role of visceral adipose tissue, intrapancreatic fat, adipose tissue inflammation, and adipokines on pancreatic cancer development. Current research on lipocalin-2, fibroblast growth factor 21, and Wnt5a is discussed. Furthermore, the significance of obesity-associated insulin resistance with hyperinsulinemia and obesity-induced gut dysbiosis with metabolic endotoxemia is reviewed. Given the central role that is occupied by the adipose tissue in obesity-promoted pancreatic cancer development, preventive and interceptive strategies should be aimed at attenuating obesity-associated adipose tissue inflammation and/or at targeting specific molecules that mechanistically link adipose tissue with pancreatic cancer in obese patients.

The adiponectin signalling pathway - A therapeutic target for the cardiac complications of type 2 diabetes?

Diabetes is associated with an increased risk of heart failure (HF). This is commonly termed diabetic cardiomyopathy and is often characterised by increased cardiac fibrosis, pathological hypertrophy, increased oxidative and endoplasmic reticulum stress as well as diastolic dysfunction. Adiponectin is a cardioprotective adipokine that is downregulated in settings of type 2 diabetes (T2D) and obesity. Furthermore, both adiponectin receptors (AdipoR1 and R2) are also downregulated in these settings which further results in impaired cardiac adiponectin signalling and reduced cardioprotection. In many cardiac pathologies, adiponectin signalling has been shown to protect against cardiac remodelling and lipotoxicity, however its cardioprotective actions in T2D-induced cardiomyopathy remain unresolved. Diabetic cardiomyopathy has historically lacked effective treatment options. In this review, we summarise the current evidence for links between the suppressed adiponectin signalling pathway and cardiac dysfunction, in diabetes. We describe adiponectin receptor-mediated signalling pathways that are normally associated with cardioprotection, as well as current and potential future therapeutic approaches that could target this pathway as possible interventions for diabetic cardiomyopathy.

Targeting Adipokines in Obesity-Related Tumors

Obesity, a global epidemic, is an independent risk factor for the occurrence and development of a variety of tumors, such as breast cancer, pancreatic cancer, ovarian cancer and colorectal cancer. Adipocytes are important endocrine cells in the tumor microenvironment of obesity-related tumors, which can secrete a variety of adipokines (such as leptin, adiponectin, estrogen, resistin, MIF and MCP-1, etc.), among which leptin, adiponectin and estrogen are the most in-depth and valuable ones. These adipokines are closely related to tumorigenesis and the progression of tumors. In recent years, more and more studies have shown that under chronic inflammatory conditions such as obesity, adipocytes secrete more adipokines to promote the tumorigenesis and development of tumors. However, it is worth noting that although adiponectin is also secreted by adipocytes, it has an anti-tumor effect, and can cross-talk with other adipokines (such as leptin and estrogen) and insulin to play an anti-tumor effect together. In addition, obesity is the main cause of insulin resistance, which can lead to the increase of the expression levels of insulin and insulin-like growth factor (IGF). As important regulators of blood glucose and lipid metabolism, insulin and IGF also play an important role in the progress of obesity related tumors. In view of the important role of adipokines secreted by adipocytes and insulin/IGF in tumors, this article not only elaborates leptin, adiponectin and estrogen secreted by adipocytes and their mechanism of action in the development of obesity- related tumors, but also introduces the relationship between insulin/IGF, a regulator of lipid metabolism, and obesity related tumors. At the same time, it briefly describes the cancer-promoting mechanism of resistin, MIF and MCP-1 in obesity-related tumors, and finally summarizes the specific treatment opinions and measures for various adipokines and insulin/insulin-like growth factors in recent years.