Niacin alleviates TRAIL-mediated colon cancer cell death via autophagy flux activation

IL-8 and PI3K pathway influence the susceptibility of TRAIL-sensitive colorectal cancer cells to TRAIL-induced cell death

BACKGROUND

Tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is an apoptosis inducer that exhibits an ideal therapeutic safety profile with less adverse effects than conventional chemotherapy. However, the occurrence of TRAIL resistance has been reported in various cancers including colorectal cancer (CRC). Substantial efforts have been channelled towards managing TRAIL resistance including identifying molecular targets. Interleukins (ILs) have been recently shown to play critical roles in modulating TRAIL sensitivity in cancer cells.

METHODS AND RESULTS

This study investigated the roles of two ILs, IL-8 and IL⍺, in TRAIL resistance in CRC. TRAIL-resistant HT-29 and TRAIL-sensitive HCT 116 cells, were treated with human recombinant IL-8 and IL-1⍺. The results indicated that treatment with IL-8 (2.5 ng/mL) significantly protected TRAIL-sensitive HCT 116 cells from TRAIL-induced cell death (p < 0.05). However, IL-1⍺ did not play a role in modulating CRC cells' responses to TRAIL. Data from RT-qPCR and Western blotting revealed the molecular regulations of IL-8 on TRAIL decoy receptor genes (OPG) and autophagy-related genes (BECN1 and LC3B) expression. The activation of the phosphoinositide 3-kinase (PI3K) pathway was shown to counteract TRAIL-induced cell death. By inhibiting its activation with wortmannin, the protective role of IL-8 against TRAIL treatment was reversed, suggesting the involvement of the PI3K pathway.

CONCLUSION

Collectively, findings from this study identified the role of IL-8 and PI3K in modulating CRC cells' sensitivity to TRAIL. Further validation of these two potential molecular targets is warranted to overcome TRAIL resistance in CRC.

The Pleiotropic Effects of Lipid-Modifying Interventions: Exploring Traditional and Emerging Hypolipidemic Therapies

Atherosclerotic cardiovascular disease poses a significant global health issue, with dyslipidemia standing out as a major risk factor. In recent decades, lipid-lowering therapies have evolved significantly, with statins emerging as the cornerstone treatment. These interventions play a crucial role in both primary and secondary prevention by effectively reducing cardiovascular risk through lipid profile enhancements. Beyond their primary lipid-lowering effects, extensive research indicates that these therapies exhibit pleiotropic actions, offering additional health benefits. These include anti-inflammatory properties, improvements in vascular health and glucose metabolism, and potential implications in cancer management. While statins and ezetimibe have been extensively studied, newer lipid-lowering agents also demonstrate similar pleiotropic effects, even in the absence of direct cardiovascular benefits. This narrative review explores the diverse pleiotropic properties of lipid-modifying therapies, emphasizing their non-lipid effects that contribute to reducing cardiovascular burden and exploring emerging benefits for non-cardiovascular conditions. Mechanistic insights into these actions are discussed alongside their potential therapeutic implications.

Autophagy/ferroptosis in colorectal cancer: Carcinogenic view and nanoparticle-mediated cell death regulation

The cell death mechanisms have a long history of being evaluated in diseases and pathological events. The ability of triggering cell death is considered to be a promising strategy in cancer therapy, but some mechanisms have dual functions in cancer, requiring more elucidation of underlying factors. Colorectal cancer (CRC) is a disease and malignant condition of colon and rectal that causes high mortality and morbidity. The autophagy targeting in CRC is therapeutic importance and this cell death mechanism can interact with apoptosis in inhibiting or increasing apoptosis. Autophagy has interaction with ferroptosis as another cell death pathway in CRC and can accelerate ferroptosis in suppressing growth and invasion. The dysregulation of autophagy affects the drug resistance in CRC and pro-survival autophagy can induce drug resistance. Therefore, inhibition of protective autophagy enhances chemosensitivity in CRC cells. Moreover, autophagy displays interaction with metastasis and EMT as a potent regulator of invasion in CRC cells. The same is true for ferroptosis, but the difference is that function of ferroptosis is determined and it can reduce viability. The lack of ferroptosis can cause development of chemoresistance in CRC cells and this cell death mechanism is regulated by various pathways and mechanisms that autophagy is among them. Therefore, current review paper provides a state-of-art analysis of autophagy, ferroptosis and their crosstalk in CRC. The nanoparticle-mediated regulation of cell death mechanisms in CRC causes changes in progression. The stimulation of ferroptosis and control of autophagy (induction or inhibition) by nanoparticles can impair CRC progression. The engineering part of nanoparticle synthesis to control autophagy and ferroptosis in CRC still requires more attention.

The role of autophagy protein Atg5 in multiple sclerosis

Multiple sclerosis (MS) is a neurological disease which has a strong autoimmune component to its pathology. Although there are currently many approved immunomodulatory treatments that reduce the rate of relapse and slow down the progression of the disease, the cure is still elusive. This may be due to the underlying etiology still being unknown. Autophagy is the potential link between neurodegeneration and autoimmunity. Specifically, this review will focus on the autophagy protein Atg5 and examine the in vitro cell culture, animal and human studies that have examined its expression and effects in the context of MS. The findings of these investigations are summarized, and a model is proposed in which elevated Atg5 levels leads to dysfunctional autophagy, neurodegeneration, inflammation, and eventually clinical disability. While there are currently no drugs that specifically target Atg5, our review recommends that further investigations into the role that Atg5 plays in MS pathophysiology may eventually lead to the development of autophagy-specific treatments of MS.

The effects of FTO gene rs9939609 polymorphism on the association between colorectal cancer and dietary intake

Background

FTO gene is associated with obesity, dietary intake, and the risk of colorectal cancer (CRC). In this study, patients with colorectal cancer were assessed for the interactions between FTO gene polymorphisms and dietary intake.

Methods

This case-control study was carried out on 450 participants aged 35-70 years including 150 patients with colorectal cancer and 300 healthy controls. Blood samples were collected in order to extract DNA and genotyping of FTO gene for rs9939609 polymorphism. A validated 168-item food frequency questionnaire (FFQ) and the Nutritionist-IV software were used to assess dietary intake.

Results

In the participants with the TT genotype of FTO rs9939609 polymorphism, CRC risk was significantly associated with higher intake of dietary fat (OR:1.87 CI95%:1.76-1.99, p = 0.04), vitamin B3 (OR:1.20 CI95%:1.08-1.65, p = 0.04), and vitamin C (OR:1.06 CI95%:1.03-1.15, p = 0.04) and lower intake of β-carotene (OR:0.98 CI95%:0.97-0.99, p = 0.03), vitamin E (OR:0.77 CI95%:0.62-0.95, p = 0.02), vitamin B1 (OR:0.15 CI95%:0.04-0.50, p < 0.01), and biotin (OR:0.72 CI95%:0.0.57-0.92, p = 0.01). No significant association was found between CRC and dietary intake in carriers of AA/AT genotypes after adjustments for the confounders.

Conclusion

CRC risk may be decreased by β-carotene, vitamins E, B1, and biotin only in those without the risk allele of the FTO gene. The association of CRC and diet may be influenced by FTO genotype. Further studies are warranted.

Potential of curcumin and niacin-loaded targeted chitosan coated liposomes to activate autophagy in hepatocellular carcinoma cells: An in vitro evaluation in HePG2 cell line

The objective of this study is to activate autophagy in hepatocellular carcinoma for the enhancement of its cellular degradation. Liposomes incorporated chitosan in the core used to improve the stability of lecithin and increase the niacin loading efficiency. Additionally, curcumin as a hydrophobic molecule entrapped into liposomal layers and used as a face layer to minimize the release of niacin in physiological pH 7.2. Folic acid-conjugated chitosan was used to facilitate the delivery of liposomes into a specific location of cancer cells. TEM, UV Visible spectrophotometer, and FTIR confirmed the successful liposomal formation and good encapsulation efficiency. Based on the cellular proliferation of HePG2, the results revealed that there was a significant inhibition of growth rate of HePG2 after 48 h of incubation at a concentration of 100 μg/mL by 91 % ± 1 %, P ≤ 0.002 (pure niacin), 55 % ± 3 %, P ≤ 0.001 (pure curcumin), 83 % ± 1.5 %, P ≤ 0.001 (niacin NPs), and 51 % ± 1.5 % P ≤ 0.0001 (curcumin-niacin NPs) of relative to the control. Increasingly, The expression of mRNA of mTOR was significantly increased by 0.72 ± 0.08 P ≤ 0.001, 1 ± 0.1, 0. P ≤ 0.001, 5 ± 0.07 P ≤ 0.01, and 1.3 ± 0.02 P ≤ 0.001 folds) in pure niacin, pure curcumin, niacin NPs and curcumin -niacin NPs, respectively, relative to the control with an expression of 0.3 ± 0.08. Additionally, the expression of p62 mRNA was significantly increased by 0.92 ± 0.07 P ≤ 0.05, 1.7 ± 0.07 P ≤ 0.0001, 0.72 ± 0.08 P ≤ 0.5, and 2.1 ± 0.1 P ≤ 0.0001 folds relative to that of the control with an expression of 0.72 ± 0.08. The results highlight the efficient therapies of biomaterials derived from natural sources that can be used in cancer therapies instead of traditional chemotherapies.

Drug repositioning for esophageal squamous cell carcinoma

Esophageal cancer (EC) remains a significant challenge globally, having the 8th highest incidence and 6th highest mortality worldwide. Esophageal squamous cell carcinoma (ESCC) is the most common form of EC in Asia. Crucially, more than 90% of EC cases in China are ESCC. The high mortality rate of EC is likely due to the limited number of effective therapeutic options. To increase patient survival, novel therapeutic strategies for EC patients must be devised. Unfortunately, the development of novel drugs also presents its own significant challenges as most novel drugs do not make it to market due to lack of efficacy or safety concerns. A more time and cost-effective strategy is to identify existing drugs, that have already been approved for treatment of other diseases, which can be repurposed to treat EC patients, with drug repositioning. This can be achieved by comparing the gene expression profiles of disease-states with the effect on gene-expression by a given drug. In our analysis, we used previously published microarray data and identified 167 differentially expressed genes (DEGs). Using weighted key driver analysis, 39 key driver genes were then identified. These driver genes were then used in Overlap Analysis and Network Analysis in Pharmomics. By extracting drugs common to both analyses, 24 drugs are predicted to demonstrate therapeutic effect in EC patients. Several of which have already been shown to demonstrate a therapeutic effect in EC, most notably Doxorubicin, which is commonly used to treat EC patients, and Ixazomib, which was recently shown to induce apoptosis and supress growth of EC cell lines. Additionally, our analysis predicts multiple psychiatric drugs, including Venlafaxine, as repositioned drugs. This is in line with recent research which suggests that psychiatric drugs should be investigated for use in gastrointestinal cancers such as EC. Our study shows that a drug repositioning approach is a feasible strategy for identifying novel ESCC therapies and can also improve the understanding of the mechanisms underlying the drug targets.

Autophagy-inducing nutritional interventions in experimental and clinical oncology

Numerous pro-autophagic dietary interventions are being investigated for their potential cancer-preventive or therapeutic effects. This applies to different fasting regimens, methionine restriction and ketogenic diets. In addition, the supplementation of specific micronutrients such as nicotinamide (vitamin B3) or spermidine induces autophagy. In humans, leanness, plant-based diets (that may lead to partial methionine restriction) and high dietary uptake of spermidine are associated with a low incidence of cancers. Moreover, clinical trials have demonstrated the capacity of nicotinamide to prevent non-melanoma skin carcinogenesis. Multiple interventional trials are evaluating the capacity of autophagy-inducing regimens to improve the outcome of chemotherapy and immunotherapy. Here, we discuss the mechanistic underpinnings of autophagy induction by nutritional interventions, as well as the mechanisms through which autophagy induction in malignant or immune cells improves anticancer immunosurveillance.

Dietary methyl donor nutrients, DNA mismatch repair polymorphisms, and risk of colorectal cancer based on microsatellite instability status

PURPOSE

Colorectal cancer (CRC) is a heterogeneous disease caused by complex interplay among the diet, the environment, and genetics involving numerous molecules and pathological pathways. This study aimed to determine whether methyl donor nutrients are associated with CRC and how these associations are altered by DNA mismatch repair (MMR) genes.

METHODS

In total, 626 cases and 838 age- and sex-matched controls were recruited for this case-control study. A validated food frequency questionnaire was used to assess seven methyl donor nutrients (vitamin B₂, niacin, B₆, folate, B₁₂, methionine, and choline). MMR polymorphisms were genotyped using an Illumina MEGA-Expanded Array. For the 626 patients, the microsatellite instability status and immunohistochemical expression of MMR proteins were analyzed. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Among the methyl donor nutrients, B₂, niacin, B₆, folate, and methionine were inversely associated with CRC risk, while a high intake of choline increased CRC. Regarding MMR genes, three hMSH3 polymorphisms (rs32952 A > C, rs41097 A > G, and rs245404 C > G) reduced CRC risk. Regarding gene-diet interactions, a stronger interaction effect was observed in G allele carriers of hMSH3 rs41097 with high niacin intake than in AA carriers with low niacin intake (OR, 95% CI = 0.49, 0.33-0.72, P for interaction = 0.02) in subgroups of patients with distal colon cancer (P for interaction = 0.008) and MMR proficiency with microsatellite stability (P for interaction = 0.021).

CONCLUSIONS

Methyl donor nutrients may affect CRC risk leading to a balance in the MMR machinery.

Enhancing autophagy in Alzheimer's disease through drug repositioning

Alzheimer's disease (AD) is one of the biggest human health threats due to increases in aging of the global population. Unfortunately, drugs for treating AD have been largely ineffective. Interestingly, downregulation of macroautophagy (autophagy) plays an essential role in AD pathogenesis. Therefore, targeting autophagy has drawn considerable attention as a therapeutic approach for the treatment of AD. However, developing new therapeutics is time-consuming and requires huge investments. One of the strategies currently under consideration for many diseases is "drug repositioning" or "drug repurposing". In this comprehensive review, we have provided an overview of the impact of autophagy on AD pathophysiology, reviewed the therapeutics that upregulate autophagy and are currently used in the treatment of other diseases, including cancers, and evaluated their repurposing as a possible treatment option for AD. In addition, we discussed the potential of applying nano-drug delivery to neurodegenerative diseases, such as AD, to overcome the challenge of crossing the blood brain barrier and specifically target molecules/pathways of interest with minimal side effects.

Novel Derivatives of Nicotinic Acid as Promising Anticancer Agents

BACKGROUND

Cancer has become the second leading cause of death worldwide. Despite of the availability of significant number of anticancer agents, cancer is still incurable especially at the last stages. Remarkable targets for anticancer research and drug discovery are heterocyclic compounds, and among them, superior effect has been shown by the nitrogen containing compounds than non-nitrogen containing compounds. Nicotinic acid, a nitrogen containing moiety and its derivatives have gained an immense importance in the development of anticancer drugs owing to the wide variety of biological properties displayed by them.

OBJECTIVE

The objective of this review is to provide researchers the information about various synthetic approaches used for the synthesis of anticancer drugs of nicotinic acid from 2001 onwards and to reveal their application and importance in the treatment of this dreadful disease.

CONCLUSION

As indicated by this review, considerable work has been done in terms of synthesis and investigation of anticancer potential of nicotinamide derivatives. The information provided in this article may be of great value for the researchers seeking to develop efficient anticancer drugs.

A systems pharmacology approach to identify the autophagy-inducing effects of Traditional Persian medicinal plants

Aging is correlated with several complex diseases, including type 2 diabetes, neurodegeneration diseases, and cancer. Identifying the nature of this correlation and treatment of age-related diseases has been a major subject of both modern and traditional medicine. Traditional Persian Medicine (TPM) embodies many prescriptions for the treatment of ARDs. Given that autophagy plays a critical role in antiaging processes, the present study aimed to examine whether the documented effect of plants used in TPM might be relevant to the induction of autophagy? To this end, the TPM-based medicinal herbs used in the treatment of the ARDs were identified from modern and traditional references. The known phytochemicals of these plants were then examined against literature for evidence of having autophagy inducing effects. As a result, several plants were identified to have multiple active ingredients, which indeed regulate the autophagy or its upstream pathways. In addition, gene set enrichment analysis of the identified targets confirmed the collective contribution of the identified targets in autophagy regulating processes. Also, the protein-protein interaction (PPI) network of the targets was reconstructed. Network centrality analysis of the PPI network identified mTOR as the key network hub. Given the well-documented role of mTOR in inhibiting autophagy, our results hence support the hypothesis that the antiaging mechanism of TPM-based medicines might involve autophagy induction. Chemoinformatics study of the phytochemicals using docking and molecular dynamics simulation identified, among other compounds, the cyclo-trijuglone of Juglans regia L. as a potential ATP-competitive inhibitor of mTOR. Our results hence, provide a basis for the study of TPM-based prescriptions using modern tools in the quest for developing synergistic therapies for ARDs.

Nicotinamide as a Foundation for Treating Neurodegenerative Disease and Metabolic Disorders

Neurodegenerative disorders impact more than one billion individuals worldwide and are intimately tied to metabolic disease that can affect another nine hundred individuals throughout the globe. Nicotinamide is a critical agent that may offer fruitful prospects for neurodegenerative diseases and metabolic disorders, such as diabetes mellitus. Nicotinamide protects against multiple toxic environments that include reactive oxygen species exposure, anoxia, excitotoxicity, ethanolinduced neuronal injury, amyloid (Aß) toxicity, age-related vascular disease, mitochondrial dysfunction, insulin resistance, excess lactate production, and loss of glucose homeostasis with pancreatic β-cell dysfunction. However, nicotinamide offers cellular protection in a specific concentration range, with dosing outside of this range leading to detrimental effects. The underlying biological pathways of nicotinamide that involve the silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), the mechanistic target of rapamycin (mTOR), AMP activated protein kinase (AMPK), and mammalian forkhead transcription factors (FoxOs) may offer insight for the clinical translation of nicotinamide into a safe and efficacious therapy through the modulation of oxidative stress, apoptosis, and autophagy. Nicotinamide is a highly promising target for the development of innovative strategies for neurodegenerative disorders and metabolic disease, but the benefits of this foundation depend greatly on gaining a further understanding of nicotinamide's complex biology.

Nicotinamide attenuates cyclophosphamide-induced hepatotoxicity in SD rats by reducing oxidative stress and apoptosis

Cyclophosphamide (CP) is a widely used anticancer and immunosuppressant drug. Nevertheless, clinical utilization of CP is limited due to considerable adverse effects and toxicities. Nicotinamide (NMD) is a micronutrient and the effect of NMD against CP-induced hepatotoxicity is yet unexplored. The present study was designed to evaluate the chemoprotective effect of NMD against CP-induced hepatic injury in Sprague-Dawley rats. Hepatotoxicity was induced by the administration of CP (30 mg/kg/day) for 10 consecutive days by intraperitoneal injection. The chemoprotective effect of NMD treatment (200 mg/kg) against CP-induced hepatotoxicity was evaluated by the oxidative stress, liver function, histopathological changes, and DNA damage. NMD cotreatment significantly reduced CP-induced oxidative stress, histological changes, and apoptosis in the liver. The present study demonstrated that NMD treatment ameliorated CP-induced hepatic damage by improving the antioxidant system and reducing DNA damage. The present findings revealed that NMD supplementation might be useful to reduce CP-associated hepatotoxicity, and thereby can increase the therapeutic utility of CP.

New Insights for nicotinamide: Metabolic disease, autophagy, and mTOR

Metabolic disorders, such as diabetes mellitus (DM), are increasingly becoming significant risk factors for the health of the global population and consume substantial portions of the gross domestic product of all nations. Although conventional therapies that include early diagnosis, nutritional modification of diet, and pharmacological treatments may limit disease progression, tight serum glucose control cannot prevent the onset of future disease complications. With these concerns, novel strategies for the treatment of metabolic disorders that involve the vitamin nicotinamide, the mechanistic target of rapamycin (mTOR), mTOR Complex 1 (mTORC1), mTOR Complex 2 (mTORC2), AMP activated protein kinase (AMPK), and the cellular pathways of autophagy and apoptosis offer exceptional promise to provide new avenues of treatment. Oversight of these pathways can promote cellular energy homeostasis, maintain mitochondrial function, improve glucose utilization, and preserve pancreatic beta-cell function. Yet, the interplay among mTOR, AMPK, and autophagy pathways can be complex and affect desired clinical outcomes, necessitating further investigations to provide efficacious treatment strategies for metabolic dysfunction and DM.

Neferine treatment enhances the TRAIL‑induced apoptosis of human prostate cancer cells via autophagic flux and the JNK pathway

Prostate cancer (PCa) is a common type of cancer among males, with a relatively high mortality rate. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a member of the tumor necrosis factor (TNF) family, initiates the apoptosis of certain cancer cells. Neferine, a primary ingredient of bisbenzylisoquinoline alkaloids, has various antitumor activities. The present study examined the effects of neferine treatment on human PCa cells. Human prostate cancer (DU145) cells were treated with neferine for 18 h, and subsequently treated with TRAIL for 2 h. Combined treatment with neferine and TRAIL significantly decreased cell viability compared to treatment with TRAIL alone. Furthermore, neferine treatment decreased the expression of p62 and increased LC3B-II expression, as assessed by western blot analysis and immunocytochemistry. It was alsp demonstrated that neferine and TRAIL act synergistically to trigger autophagy in PCa cells, as revealed by autophagosome formation, LC3B-II accumulation demonstrated by transmission electron microscopy (TEM) analysis and phosphorylated c-Jun N-terminal kinase (p-JNK) upregulation. When the autophagic flux was attenuated by the inhibitor, chloroquine, or by genetically modified ATG5 siRNA, the enhancement of TRAIL-induced autophagy by neferine-induced was also attenuated. Furthermore, treatment with the JNK inhibitor, SP600125, distinctly increased the viability of the cells treated with neferine and TRAIL. On the whole, the findings of the present study demonstrate that neferine treatment effectively promotes TRAIL-mediated cell death and this effect likely occurs via the autophagic flux and the JNK pathway.

Nicotinamide: Oversight of Metabolic Dysfunction Through SIRT1, mTOR, and Clock Genes

Metabolic disorders that include diabetes mellitus present significant challenges for maintaining the welfare of the global population. Metabolic diseases impact all systems of the body and despite current therapies that offer some protection through tight serum glucose control, ultimately such treatments cannot block the progression of disability and death realized with metabolic disorders. As a result, novel therapeutic avenues are critical for further development to address these concerns. An innovative strategy involves the vitamin nicotinamide and the pathways associated with the silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), the mechanistic target of rapamycin (mTOR), mTOR Complex 1 (mTORC1), mTOR Complex 2 (mTORC2), AMP activated protein kinase (AMPK), and clock genes. Nicotinamide maintains an intimate relationship with these pathways to oversee metabolic disease and improve glucose utilization, limit mitochondrial dysfunction, block oxidative stress, potentially function as antiviral therapy, and foster cellular survival through mechanisms involving autophagy. However, the pathways of nicotinamide, SIRT1, mTOR, AMPK, and clock genes are complex and involve feedback pathways as well as trophic factors such as erythropoietin that require a careful balance to ensure metabolic homeostasis. Future work is warranted to gain additional insight into these vital pathways that can oversee both normal metabolic physiology and metabolic disease.

A Combination Treatment Strategy for Hemorrhagic Shock in a Rat Model Modulates Autophagy

Hemorrhagic shock leads to whole body hypoxia and nutrient deprivation resulting in organ dysfunction and mortality. Previous studies demonstrated that resveratrol, dichloroacetate, and niacin improve organ function and survival in rats following hemorrhagic shock injury (HI). We hypothesized that a combinatorial formula that collectively promotes survival will decrease the dose of individual compounds toward effective therapy for HI. Sprague-Dawley rats were subjected to HI by withdrawing 60% blood volume. NiDaR (Niacin-Dichloroacetate-Resveratrol; 2 mg/kg dose of each) or vehicle was administered following the shock in the absence of fluid resuscitation, and survival monitored. In order to study alterations in molecular mediators, separate groups of rats were administered NiDaR or vehicle along with resuscitation fluid, following HI. We observed significant improvement (p < 0.05) in survival following HI in animals that received NiDaR, in the absence of fluid resuscitation. In NiDaR treated animals that received resuscitation fluid, MAP was significantly increased compared to Veh-treated rats. HI-induced increase in systemic IL-6 levels and tissue expression of IL-6, IL-10, IL-1β, and IL-18 genes in the heart were attenuated with NiDaR treatment. NiDaR promoted autophagy following HI as demonstrated by reduced p-mTOR, increased p-ULK1 and p-Beclin. The combinatorial formula, NiDaR, reduced inflammation, promoted autophagy, and reduced doses of individual compounds used, and may be more effective in genetically heterogeneous population. In conclusion our experiments demonstrated that the combinatorial drug treatment has salutary effect in rats following HI.

B Vitamins and Fatty Acids: What Do They Share with Small Vessel Disease-Related Dementia?

Many studies have been written on vitamin supplementation, fatty acid, and dementia, but results are still under debate, and no definite conclusion has yet been drawn. Nevertheless, a significant amount of lab evidence confirms that vitamins of the B group are tightly related to gene control for endothelium protection, act as antioxidants, play a co-enzymatic role in the most critical biochemical reactions inside the brain, and cooperate with many other elements, such as choline, for the synthesis of polyunsaturated phosphatidylcholine, through S-adenosyl-methionine (SAM) methyl donation. B-vitamins have anti-inflammatory properties and act in protective roles against neurodegenerative mechanisms, for example, through modulation of the glutamate currents and a reduction of the calcium currents. In addition, they also have extraordinary antioxidant properties. However, laboratory data are far from clinical practice. Many studies have tried to apply these results in everyday clinical activity, but results have been discouraging and far from a possible resolution of the associated mysteries, like those represented by Alzheimer's disease (AD) or small vessel disease dementia. Above all, two significant problems emerge from the research: No consensus exists on general diagnostic criteria-MCI or AD? Which diagnostic criteria should be applied for small vessel disease-related dementia? In addition, no general schema exists for determining a possible correct time of implementation to have effective results. Here we present an up-to-date review of the literature on such topics, shedding some light on the possible interaction of vitamins and phosphatidylcholine, and their role in brain metabolism and catabolism. Further studies should take into account all of these questions, with well-designed and world-homogeneous trials.

The Plasma NAD+ Metabolome Is Dysregulated in "Normal" Aging

Nicotinamide adenine dinucleotide (NAD⁺) is an essential pyridine nucleotide that serves as an electron carrier in cellular metabolism and plays a crucial role in the maintenance of balanced redox homeostasis. Quantification of NAD⁺:NADH and NADP⁺:NADPH ratios are pivotal to a wide variety of cellular processes, including intracellular secondary messenger signaling by CD38 glycohydrolases, DNA repair by poly(adenosine diphosphate ribose) polymerase (PARP), epigenetic regulation of gene expression by NAD-dependent histone deacetylase enzymes known as sirtuins, and regulation of the oxidative pentose phosphate pathway. We quantified changes in the NAD⁺ metabolome in plasma samples collected from consenting healthy human subjects across a wide age range (20-87 years) using liquid chromatography coupled to tandem mass spectrometry. Our data show a significant decline in the plasma levels of NAD⁺, NADP⁺, and other important metabolites such as nicotinic acid adenine dinucleotide (NAAD) with age. However, an age-related increase in the reduced form of NAD⁺ and NADP⁺-NADH and NADPH-and nicotinamide (NAM), N-methyl-nicotinamide (MeNAM), and the products of adenosine diphosphoribosylation, including adenosine diphosphate ribose (ADPR) was also reported. Whereas, plasma levels of nicotinic acid (NA), nicotinamide mononucleotide (NMN), and nicotinic acid mononucleotide (NAMN) showed no statistically significant changes across age groups. Taken together, our data cumulatively suggest that age-related impairments are associated with corresponding alterations in the extracellular plasma NAD⁺ metabolome. Our future research will seek to elucidate the role of modulating NAD⁺ metabolites in the treatment and prevention of age-related diseases.

Autophagy as a mechanism of Apo2L/TRAIL resistance

Apo2 ligand (Apo2L)/tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is unique to selectively induce apoptosis in tumor cells while sparing normal cells. Thus there is tremendous interest in Apo2L/TRAIL therapy; however, drug resistance is a serious limitation. Autophagy is a cellular housekeeping process that controls protein and organelle turnover, and is almost consistently activated in response to apoptosis-inducing stimuli, including Apo2L/TRAIL. Unlike apoptosis, autophagy leads to cell death or survival depending on the context. Various molecular mechanisms by which autophagy regulates Apo2L/TRAIL-induced apoptosis have been identified. Further, whether autophagy is completed (intact autophagic flux) or not could determine the fate of cancer cells, either cell survival or death. Thus, targeting autophagy is an attractive strategy to overcome Apo2L/TRAIL resistance. We present the current view of how these regulatory mechanisms of this interplay between autophagy and apoptosis may dictate cancer cell response to Apo2L/TRAIL therapy.

Azithromycin enhances anticancer activity of TRAIL by inhibiting autophagy and up-regulating the protein levels of DR4/5 in colon cancer cells in vitro and in vivo

Background

Azithromycin is a member of macrolide antibiotics, and has been reported to inhibit the proliferation of cancer cells. However, the underlying mechanisms are not been fully elucidated. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively targets tumor cells without damaging healthy cells. In the present study, we examined whether azithromycin is synergistic with TRAIL, and if so, the underlying mechanisms in colon cancers.

Methods

HCT-116, SW480, SW620 and DiFi cells were treated with azithromycin, purified TRAIL, or their combination. A sulforhoddamine B assay was used to examine cell survival. Apoptosis was examined using annexin V-FITC/PI staining, and autophagy was observed by acridine orange staining. Western blot analysis was used to detect protein expression levels. In mechanistic experiments, siRNAs were used to knockdown death receptors (DR4, DR5) and LC-3B. The anticancer effect of azithromycin and TRAIL was also examined in BALB/c nude mice carrying HCT-116 xenografts.

Results

Azithromycin decreased the proliferation of HCT-116 and SW480 cells in a dose-dependent manner. Combination of azithromycin and TRAIL inhibited tumor growth in a manner that could not be explained by additive effects. Azithromycin increased the expressions of DR4, DR5, p62 and LC-3B proteins and potentiated induction of apoptosis by TRAIL. Knockdown of DR4 and DR5 with siRNAs increased cell survival rate and decreased the expression of cleaved-PARP induced by the combination of azithromycin and TRAIL. LC-3B siRNA and CQ potentiated the anti-proliferation activity of TRAIL alone, and increased the expressions of DR4 and DR5.

Conclusion

The synergistic antitumor effect of azithromycin and TRAIL mainly relies on the up-regulations of DR4 and DR5, which in turn result from LC-3B-involved autophagy inhibition.

Electronic supplementary material

The online version of this article (10.1186/s40880-018-0309-9) contains supplementary material, which is available to authorized users.

CPNE1 Is a Useful Prognostic Marker and Is Associated with TNF Receptor-Associated Factor 2 (TRAF2) Expression in Prostate Cancer

Background

CPNE1 plays a vital role in regulating cell differentiation. The clinical and biological values of CPNE1 in prostate cancer are still unclear. The aim of this study was to investigate the clinicopathological value of CPNE1 and the association of CPNE1 with TRAF2 expression in patients with prostate cancer.

Material/Methods

CPNE1 expression in prostate cancer was analyzed using Gene Expression Omnibus (GEO) databases. The Cancer Genome Atlas (TCGA) dataset was used to investigate the association of CPNE1 expression with TRAF2 expression in prostate cancer. The association of CPNE1 expression with recurrence-free survival in patients was also analyzed using the TCGA dataset. Immunohistochemistry assay was performed to examine CPNE1 expression in 65 normal prostate samples and 114 prostate cancer samples. The recurrence-free survival in patients was evaluated using Kaplan-Meier curves and log-rank test. In addition, multivariate and univariate analyses of prognostic factors were investigated by Cox regression. The effect of CPNE1 on TRAF2 expression was explored in human prostate cancer DU-145 cells.

Results

Our results showed that expression level of CPNE1 is higher in prostate cancer than in normal prostate tissues (P=0.006). In the GSE35988 dataset, CPNE1 expression was found to be upregulated in castration-resistant prostate cancer compared with non-castration-resistant prostate cancer (P<0.001). Furthermore, we found that CPNE1 high expression was significantly related to tumor stage, Gleason score, and poorer biochemical recurrence-free survival in prostate cancer patients. Co-expression analysis of TCGA data showed that CPNE1 is significantly associated with TRAF2 expression. CPNE1 overexpression can upregulate TRAF2 expression in prostate cancer DU-145 cells as determined by Western blotting and immunofluorescence assays.

Conclusions

Overall, our findings suggest that CPNE1 is a valuable prognostic marker for evaluating recurrence-free survival and is positively related to TRAF2 expression in prostate cancer.

Enhancement of TRAIL-induced apoptosis by 5-fluorouracil requires activating Bax and p53 pathways in TRAIL-resistant lung cancers

Lung cancer, especially lung adenocarcinoma, is one of the main causes of death worldwide. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a primary anticancer agent and a member of the tumor necrosis factor family that selectively induces apoptosis in various tumor cells, but not in normal cells. Combination chemotherapy can be used for treating specific cancer types even at progressive stages. In the present study, we observed that 5-fluorouracil, which exerts anticancer effects by inhibiting tumor cell proliferation, enhanced TRAIL-induced apoptosis of TRAIL-resistant human adenocarcinoma A549 cells. Interestingly, 5-fluorouracil treatment markedly increased Bax and p53 levels and 5-fluorouracil and TRAIL cotreatment increased Ac-cas3 and Ac-cas8 levels compared with those in control cells. Taken together, the present study demonstrated that 5-fluorouracil enhances TRAIL-induced apoptosis in TRAIL-resistant lung adenocarcinoma cells by activating Bax and p53, and also suggest that TRAIL and 5-fluorouracil cotreatment can be used as an adequate therapeutic strategy for TRAIL-resistant human cancers.

TRAF2 is a Valuable Prognostic Biomarker in Patients with Prostate Cancer

BACKGROUND TRAF2 exerts important functions in regulating the development and progression of cancer. The aim of this study is to investigate whether TRAF2 is a valuable prognostic biomarker and to determine if it regulates TRAIL-induced apoptosis in prostate cancer. MATERIAL AND METHODS Microarray gene expression data from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were used to determine TRAF2 expression in prostate cancer. TRAF2 expression in prostate cancer was further investigated by immunohistochemistry assay. Kaplan-Meier curves and log-rank test were used to assess the recurrence-free rate. Cox regression was used to analyze prognostic factors. Effects of TRAF2 on regulating TRAIL-induced apoptosis in DU-145 cells were further investigated. RESULTS We found that TRAF2 was significantly upregulated in prostate cancer compared with normal prostate samples (P<0.001). In addition, compared with primary prostate cancer, TRAF2 was upregulated in metastatic prostate cancer (P=0.006). Furthermore, our results showed that high expression of TRAF2 was significantly associated with tumor stage of prostate cancer (P=0.035). TRAF2 high expression was associated with poorer recurrence-free survival in prostate cancer patients (P=0.013). TRAF2 was found to be a valuable independent prognostic factor for predicting recurrence-free survival (P=0.026). In addition, the present results indicate that TRAF2 affects TRAIL-induced apoptosis in prostate cancer DU-145 cells via regulating cleaved Caspase-8 and c-Flip expression. CONCLUSIONS TRAF2 could be a novel prognostic biomarker for predicting recurrence-free survival in patients with prostate cancer, which might be associated with the effects of TRAF2 in regulating TRAIL-induced apoptosis in prostate cancer cells via c-Flip/Caspase-8 signalling.

Interplay between apoptosis and autophagy in colorectal cancer

Autophagy and apoptosis are two pivotal mechanisms in mediating cell survival and death. Cross-talk of autophagy and apoptosis has been documented in the tumorigenesis and progression of cancer, while the interplay between the two pathways in colorectal cancer (CRC) has not yet been comprehensively summarized. In this study, we outlined the basis of apoptosis and autophagy machinery firstly, and then reviewed the recent evidence in cellular settings or animal studies regarding the interplay between them in CRC. In addition, several key factors that modulate the cross-talk between autophagy and apoptosis as well as its significance in clinical practice were discussed. Understanding of the interplay between the cell death mechanisms may benefit the translation of CRC treatment from basic research to clinical use.

Meat Intake and the Dose of Vitamin B3 - Nicotinamide: Cause of the Causes of Disease Transitions, Health Divides, and Health Futures?

Meat and vitamin B3 - nicotinamide - intake was high during hunter-gatherer times. Intake then fell and variances increased during and after the Neolithic agricultural revolution. Health, height, and IQ deteriorated. Low dietary doses are buffered by 'welcoming' gut symbionts and tuberculosis that can supply nicotinamide, but this co-evolved homeostatic metagenomic strategy risks dysbioses and impaired resistance to pathogens. Vitamin B3 deficiency may now be common among the poor billions on a low-meat diet. Disease transitions to non-communicable inflammatory disorders (but longer lives) may be driven by positive 'meat transitions'. High doses of nicotinamide lead to reduced regulatory T cells and immune intolerance. Loss of no longer needed symbiotic 'old friends' compounds immunological over-reactivity to cause allergic and auto-immune diseases. Inhibition of nicotinamide adenine dinucleotide consumers and loss of methyl groups or production of toxins may cause cancers, metabolic toxicity, or neurodegeneration. An optimal dosage of vitamin B3 could lead to better health, but such a preventive approach needs more equitable meat distribution. Some people may require personalised doses depending on genetic make-up or, temporarily, when under stress.