Simvastatin exerts neuroprotective effects post-stroke by ameliorating endoplasmic reticulum stress and regulating autophagy/apoptosis balance through pAMPK/LC3B/ LAMP2 axis

Statins have evident neuroprotective role in acute ischemic stroke(AIS). The pleiotropic effect by which statin exerts neuroprotective effects, needs to be explored for considering it as one of the future adjunctive therapies in AIS. Endoplasmic reticulum(ER) assists cellular survival by reducing protein aggregates during ischemic conditions. ER-stress mediated apoptosis and autophagy are predominant reasons for neuronal death in AIS. Statin exerts both anti-apoptotic and anti-autophagic effect in neurons under ischemic stress. Although the influence of statin on autophagic neuroprotection has been reported with contradictory results. Thus, in our study we have attempted to understand its influence on autophagic protection while inhibiting upregulation of autophagic death(autosis). Previously we reported, statin can alleviate apoptosis via modulating cardiolipin mediated mitochondrial dysfunction. However, the clearance of damaged mitochondria is essential for prolonged cell survival. In our study, we tried to decipher the mechanism by which statin leads to neuronal survival by the mitophagy mediated cellular clearance. Simvastatin was administered to Sprague Dawley(SD) rats both as prophylaxis and treatment. The safety and efficacy of the statin was validated by assessment of infarct size and functional outcome. A reduction in oxidative and ER-stress were observed in both the prophylactic and treatment groups. The influence of statin on autophagy/apoptosis balance was evaluated by molecular assessment of mitophagy and cellular apoptosis. Statin reduces the post-stroke ER-stress and predominantly upregulated autophagolysosome mediated mitophagy than apoptotic cell death by modulating pAMPK/LC3B/LAMP2 axis. Based on the above findings statin could be explored as an adjunctive therapy for AIS in future.

Potential of Neuroinflammation-Modulating Strategies in Tuberculous Meningitis: Targeting Microglia

Tuberculous meningitis (TBM) is the most severe complication of tuberculosis (TB) and is associated with high rates of disability and mortality. Mycobacterium tuberculosis (M. tb), the infectious agent of TB, disseminates from the respiratory epithelium, breaks through the blood-brain barrier, and establishes a primary infection in the meninges. Microglia are the core of the immune network in the central nervous system (CNS) and interact with glial cells and neurons to fight against harmful pathogens and maintain homeostasis in the brain through pleiotropic functions. However, M. tb directly infects microglia and resides in them as the primary host for bacillus infections. Largely, microglial activation slows disease progression. The non-productive inflammatory response that initiates the secretion of pro-inflammatory cytokines and chemokines may be neurotoxic and aggravate tissue injuries based on damages caused by M. tb. Host-directed therapy (HDT) is an emerging strategy for modulating host immune responses against diverse diseases. Recent studies have shown that HDT can control neuroinflammation in TBM and act as an adjunct therapy to antibiotic treatment. In this review, we discuss the diverse roles of microglia in TBM and potential host-directed TB therapies that target microglia to treat TBM. We also discuss the limitations of applying each HDT and suggest a course of action for the near future.

Pachyonychia Congenita: A Research Agenda Leading to New Therapeutic Approaches

Pachyonychia congenita (PC) is a dominantly inherited genetic disorder of cornification. PC stands out among other genodermatoses because despite its rarity, it has been the focus of a very large number of pioneering translational research efforts over the past 2 decades, mostly driven by a patient support organization, the Pachyonychia Congenita Project. These efforts have laid the ground for innovative strategies that may broadly impact approaches to the management of other inherited cutaneous and noncutaneous diseases. This article outlines current avenues of research in PC, expected outcomes, and potential hurdles.

Understanding exosomes: Part 2-Emerging leaders in regenerative medicine

Exosomes are the smallest subset of extracellular signaling vesicles secreted by most cells with the ability to communicate with other tissues and cell types over long distances. Their use in regenerative medicine has gained tremendous momentum recently due to their ability to be utilized as therapeutic options for a wide array of diseases/conditions. Over 5000 publications are currently being published yearly on this topic, and this number is only expected to dramatically increase as novel therapeutic strategies continue to be developed. Today exosomes have been applied in numerous contexts including neurodegenerative disorders (Alzheimer's disease, central nervous system, depression, multiple sclerosis, Parkinson's disease, post-traumatic stress disorders, traumatic brain injury, peripheral nerve injury), damaged organs (heart, kidney, liver, stroke, myocardial infarctions, myocardial infarctions, ovaries), degenerative processes (atherosclerosis, diabetes, hematology disorders, musculoskeletal degeneration, osteoradionecrosis, respiratory disease), infectious diseases (COVID-19, hepatitis), regenerative procedures (antiaging, bone regeneration, cartilage/joint regeneration, osteoarthritis, cutaneous wounds, dental regeneration, dermatology/skin regeneration, erectile dysfunction, hair regrowth, intervertebral disc repair, spinal cord injury, vascular regeneration), and cancer therapy (breast, colorectal, gastric cancer and osteosarcomas), immune function (allergy, autoimmune disorders, immune regulation, inflammatory diseases, lupus, rheumatoid arthritis). This scoping review is a first of its kind aimed at summarizing the extensive regenerative potential of exosomes over a broad range of diseases and disorders.

Doxorubicin-mediated cardiac dysfunction: Revisiting molecular interactions, pharmacological compounds and (nano)theranostic platforms

Although chemotherapy drugs are extensively utilized in cancer therapy, their administration for treatment of patients has faced problems that regardless of chemoresistance, increasing evidence has shown concentration-related toxicity of drugs. Doxorubicin (DOX) is a drug used in treatment of solid and hematological tumors, and its function is based on topoisomerase suppression to impair cancer progression. However, DOX can also affect the other organs of body and after chemotherapy, life quality of cancer patients decreases due to the side effects. Heart is one of the vital organs of body that is significantly affected by DOX during cancer chemotherapy, and this can lead to cardiac dysfunction and predispose to development of cardiovascular diseases and atherosclerosis, among others. The exposure to DOX can stimulate apoptosis and sometimes, pro-survival autophagy stimulation can ameliorate this condition. Moreover, DOX-mediated ferroptosis impairs proper function of heart and by increasing oxidative stress and inflammation, DOX causes cardiac dysfunction. The function of DOX in mediating cardiac toxicity is mediated by several pathways that some of them demonstrate protective function including Nrf2. Therefore, if expression level of such protective mechanisms increases, they can alleviate DOX-mediated cardiac toxicity. For this purpose, pharmacological compounds and therapeutic drugs in preventing DOX-mediated cardiotoxicity have been utilized and they can reduce side effects of DOX to prevent development of cardiovascular diseases in patients underwent chemotherapy. Furthermore, (nano)platforms are used comprehensively in treatment of cardiovascular diseases and using them for DOX delivery can reduce side effects by decreasing concentration of drug. Moreover, when DOX is loaded on nanoparticles, it is delivered into cells in a targeted way and its accumulation in healthy organs is prevented to diminish its adverse impacts. Hence, current paper provides a comprehensive discussion of DOX-mediated toxicity and subsequent alleviation by drugs and nanotherapeutics in treatment of cardiovascular diseases.

Autosomal Dominant Polycystic Kidney Disease: Is There a Role for Autophagy?

Autosomal-Dominant Polycystic Kidney Disease (ADPKD) is a monogenic disorder initiated by mutations in either PKD1 or PKD2 genes, responsible for encoding polycystin 1 and polycystin 2, respectively. These proteins are primarily located within the primary cilia. The disease follows an inexorable progression, leading most patients to severe renal failure around the age of 50, and extra-renal complications are frequent. A cure for ADPKD remains elusive, but some measures can be employed to manage symptoms and slow cyst growth. Tolvaptan, a vasopressin V2 receptor antagonist, is the only drug that has been proven to attenuate ADPKD progression. Recently, autophagy, a cellular recycling system that facilitates the breakdown and reuse of aged or damaged cellular components, has emerged as a potential contributor to the pathogenesis of ADPKD. However, the precise role of autophagy in ADPKD remains a subject of investigation, displaying a potentially twofold impact. On the one hand, impaired autophagy may promote cyst formation by inducing apoptosis, while on the other hand, excessive autophagy may lead to fibrosis through epithelial to mesenchymal transition. Promising results of autophagy inducers have been observed in preclinical studies. Clinical trials are warranted to thoroughly assess the long-term safety and efficacy of a combination of autophagy inducers with metabolic and/or aquaferetic drugs. This research aims to shed light on the complex involvement of autophagy in ADPKD, explore the regulation of autophagy in disease progression, and highlight the potential of combination therapies as a promising avenue for future investigations.

Autophagy/Mitophagy in Airway Diseases: Impact of Oxidative Stress on Epithelial Cells

Autophagy is the key process by which the cell degrades parts of itself within the lysosomes. It maintains cell survival and homeostasis by removing molecules (particularly proteins), subcellular organelles, damaged cytoplasmic macromolecules, and by recycling the degradation products. The selective removal or degradation of mitochondria is a particular type of autophagy called mitophagy. Various forms of cellular stress (oxidative stress (OS), hypoxia, pathogen infections) affect autophagy by inducing free radicals and reactive oxygen species (ROS) formation to promote the antioxidant response. Dysfunctional mechanisms of autophagy have been found in different respiratory diseases such as chronic obstructive lung disease (COPD) and asthma, involving epithelial cells. Several existing clinically approved drugs may modulate autophagy to varying extents. However, these drugs are nonspecific and not currently utilized to manipulate autophagy in airway diseases. In this review, we provide an overview of different autophagic pathways with particular attention on the dysfunctional mechanisms of autophagy in the epithelial cells during asthma and COPD. Our aim is to further deepen and disclose the research in this direction to stimulate the develop of new and selective drugs to regulate autophagy for asthma and COPD treatment.

New insights into the therapeutic potentials of statins in cancer

The widespread clinical use of statins has contributed to significant reductions of cardiovascular morbidity and mortality. Increasing preclinical and epidemiological evidences have revealed that dyslipidemia is an important risk factor for carcinogenesis, invasion and metastasis, and that statins as powerful inhibitor of HMG-CoA reductase can exert prevention and intervention effects on cancers, and promote sensitivity to anti-cancer drugs. The anti-cancer mechanisms of statins include not only inhibition of cholesterol biosynthesis, but also their pleiotropic effects in modulating angiogenesis, apoptosis, autophagy, tumor metastasis, and tumor microenvironment. Moreover, recent clinical studies have provided growing insights into the therapeutic potentials of statins and the feasibility of combining statins with other anti-cancer agents. Here, we provide an updated review on the application potential of statins in cancer prevention and treatment and summarize the underneath mechanisms, with focuses on data from clinical studies.

Anti-inflammatory effect of simvastatin by impeding TNF-α and interleukin-1ß pathways: antiangiogenic activity of simvastatin and simvastatin-loaded silver nanoparticles

PURPOSE

The present study was carried out to evaluate anti-inflammatory and antiangiogenic attributes of simvastatin and its nanofilms containing silver nanoparticles.

METHODS

Silver nanoparticles and simvastatin-loaded nanocomposite (SNSN) films were formulated by using polymeric solution (pectin + sericin) through casting solution method. Different in vitro and in vivo anti-inflammatory assays were performed. In addition, chick chorioallantoic membrane assay (CAM) was also employed for angiogenesis activity.

RESULTS

FTIR spectra of the film depicted the presence of intact simvastatin. Differential scanning calorimetry exhibited no endothermic expression in F9 film thermogram. The simvastatin release from all films exhibited a burst effect. Cotton-pellet induced granuloma model study showed that high dose of simvastatin and indomethacin produced comparable (p < 0.05) anti-inflammatory effect. Noteworthy, RT-PCR showed dose-dependent, anti-oedematous effect of simvastatin through downregulation of serum TNF-α and interleukin-1ß levels. While results of CAM assay exhibited remarkable anti-angiogenic potential of SNSN films showing dissolved blood vessels network macroscopically.

CONCLUSION

To reiterate, simvastatin and its SNSN films can add significant contribution to the field of biomedicines due to their promising anti-inflammatory and antiangiogenic properties, however, clinical studies are required to validate their commercial use.

Resveratrol in breast cancer treatment: from cellular effects to molecular mechanisms of action

Breast cancer (BC) is one of the most common cancers in females and is responsible for the highest cancer-related deaths following lung cancer. The complex tumor microenvironment and the aggressive behavior, heterogenous nature, high proliferation rate, and ability to resist treatment are the most well-known features of BC. Accordingly, it is critical to find an effective therapeutic agent to overcome these deleterious features of BC. Resveratrol (RES) is a polyphenol and can be found in common foods, such as pistachios, peanuts, bilberries, blueberries, and grapes. It has been used as a therapeutic agent for various diseases, such as diabetes, cardiovascular diseases, inflammation, and cancer. The anticancer mechanisms of RES in regard to breast cancer include the inhibition of cell proliferation, and reduction of cell viability, invasion, and metastasis. In addition, the synergistic effects of RES in combination with other chemotherapeutic agents, such as docetaxel, paclitaxel, cisplatin, and/or doxorubicin may contribute to enhancing the anticancer properties of RES on BC cells. Although, it demonstrates promising therapeutic features, the low water solubility of RES limits its use, suggesting the use of delivery systems to improve its bioavailability. Several types of nano drug delivery systems have therefore been introduced as good candidates for RES delivery. Due to RES's promising potential as a chemopreventive and chemotherapeutic agent for BC, this review aims to explore the anticancer mechanisms of RES using the most up to date research and addresses the effects of using nanomaterials as delivery systems to improve the anticancer properties of RES.

LncRNA-miRNA axis in tumor progression and therapy response: An emphasis on molecular interactions and therapeutic interventions

Epigenetic factors are critical regulators of biological and pathological mechanisms and they could interact with different molecular pathways. Targeting epigenetic factors has been an idea approach in disease therapy, especially cancer. Accumulating evidence has highlighted function of long non-coding RNAs (lncRNAs) as epigenetic factors in cancer initiation and development and has focused on their association with downstream targets. microRNAs (miRNAs) are the most well-known targets of lncRNAs and present review focuses on lncRNA-miRNA axis in malignancy and therapy resistance of tumors. LncRNA-miRNA regulates cell death mechanisms such as apoptosis and autophagy in cancers. This axis affects tumor metastasis via regulating EMT and MMPs. Besides, lncRNA-miRNA axis determines sensitivity of tumor cells to chemotherapy, radiotherapy and immunotherapy. Based on the studies, lncRNAs can be affected by drugs and genetic tools in cancer therapy and this may affect expression level of miRNAs as their downstream targets, leading to cancer suppression/progression. LncRNAs have both tumor-promoting and tumor-suppressor functions in cancer and this unique function of lncRNAs has complicated their implication in tumor therapy. LncRNA-miRNA axis can also affect other signaling networks in cancer such as PI3K/Akt, STAT3, Wnt/β-catenin and EZH2 among others. Notably, lncRNA/miRNA axis can be considered as a signature for diagnosis and prognosis in cancers.

Autophagy in asthma and chronic obstructive pulmonary disease

Autophagy (or macroautophagy) is a key cellular process that removes damaged molecules (particularly proteins) and subcellular organelles to maintain cellular homeostasis. There is growing evidence that abnormalities in autophagy may contribute to the pathogenesis of many chronic diseases, including asthma and chronic obstructive pulmonary disease (COPD). In asthma, increased autophagy plays a role in promoting type 2 immune responses and eosinophilic inflammation, whereas decreased autophagy may be important in neutrophilic asthma. Acute exposure to cigarette smoke may activate autophagy, resulting in ciliary dysfunction and death of airway epithelial cells, whereas in stable COPD most studies have demonstrated an impairment in autophagy, with reduced autophagic flux and accumulation of abnormal mitochondria (defective mitophagy) and linked to cellular senescence. Autophagy may be increased or decreased in different cell types and depending on the cellular environment, making it difficult to target autophagy therapeutically. Several existing drugs may activate autophagy, including rapamycin, metformin, carbamazepine, cardiac glycosides and statins, whereas others, such as chloroquine, inhibit this process. However, these drugs are nonspecific and more selective drugs are now in development, which may prove useful as novel agents to treat asthma and COPD in the future.

Novel Effects of Statins on Cancer via Autophagy

Cancer is one of the main causes of death globally. Most of the molecular mechanisms underlying cancer are marked by complex aberrations that activate the critical cell-signaling pathways that play a pivotal role in cell metabolism, tumor development, cytoskeletal reorganization, and metastasis. The phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of the rapamycin (PI3K/AKT/mTOR) pathway is one of the main signaling pathways involved in carcinogenesis and metastasis. Autophagy, a cellular pathway that delivers cytoplasmic components to lysosomes for degradation, plays a dual role in cancer, as either a tumor promoter or a tumor suppressor, depending on the stage of the carcinogenesis. Statins are the group of drugs of choice to lower the level of low-density lipoprotein (LDL) cholesterol in the blood. Experimental and clinical data suggest the potential of statins in the treatment of cancer. In vitro and in vivo studies have demonstrated the molecular mechanisms through which statins inhibit the proliferation and metastasis of cancer cells in different types of cancer. The anticancer properties of statins have been shown to result in the suppression of tumor growth, the induction of apoptosis, and autophagy. This literature review shows the dual role of the autophagic process in cancer and the latest scientific evidence related to the inducing effect exerted by statins on autophagy, which could explain their anticancer potential.

Molecular Mechanisms Involving the Sonic Hedgehog Pathway in Lung Cancer Therapy: Recent Advances

According to the latest statistics from the International Agency for Research on Cancer (IARC), lung cancer is one of the most lethal malignancies in the world, accounting for approximately 18% of all cancer-associated deaths. Yet, even with aggressive interventions for advanced lung cancer, the five-year survival rate remains low, at around 15%. The hedgehog signaling pathway is highly conserved during embryonic development and is involved in tissue homeostasis as well as organ development. However, studies have documented an increasing prevalence of aberrant activation of HH signaling in lung cancer patients, promoting malignant lung cancer progression with poor prognostic outcomes. Inhibitors targeting the HH pathway have been widely used in tumor therapy, however, they still cannot avoid the occurrence of drug resistance. Interestingly, natural products, either alone or in combination with chemotherapy, have greatly improved overall survival outcomes for lung cancer patients by acting on the HH signaling pathway because of its unique and excellent pharmacological properties. In this review, we elucidate on the underlying molecular mechanisms through which the HH pathway promotes malignant biological behaviors in lung cancer, as well as the potential of inhibitors or natural compounds in targeting HH signaling for clinical applications in lung cancer therapy.

Negative Modulation of Macroautophagy by Stabilized HERPUD1 is Counteracted by an Increased ER-Lysosomal Network With Impact in Drug-Induced Stress Cell Survival

Macroautophagy and the ubiquitin proteasome system work as an interconnected network in the maintenance of cellular homeostasis. Indeed, efficient activation of macroautophagy upon nutritional deprivation is sustained by degradation of preexisting proteins by the proteasome. However, the specific substrates that are degraded by the proteasome in order to activate macroautophagy are currently unknown. By quantitative proteomic analysis we identified several proteins downregulated in response to starvation independently of ATG5 expression. Among them, the most significant was HERPUD1, an ER membrane protein with low expression and known to be degraded by the proteasome under normal conditions. Contrary, under ER stress, levels of HERPUD1 increased rapidly due to a blockage in its proteasomal degradation. Thus, we explored whether HERPUD1 stability could work as a negative regulator of autophagy. In this work, we expressed a version of HERPUD1 with its ubiquitin-like domain (UBL) deleted, which is known to be crucial for its proteasome degradation. In comparison to HERPUD1-WT, we found the UBL-deleted version caused a negative role on basal and induced macroautophagy. Unexpectedly, we found stabilized HERPUD1 promotes ER remodeling independent of unfolded protein response activation observing an increase in stacked-tubular structures resembling previously described tubular ER rearrangements. Importantly, a phosphomimetic S59D mutation within the UBL mimics the phenotype observed with the UBL-deleted version including an increase in HERPUD1 stability and ER remodeling together with a negative role on autophagy. Moreover, we found UBL-deleted version and HERPUD1-S59D trigger an increase in cellular size, whereas HERPUD1-S59D also causes an increased in nuclear size. Interestingly, ER remodeling by the deletion of the UBL and the phosphomimetic S59D version led to an increase in the number and function of lysosomes. In addition, the UBL-deleted version and phosphomimetic S59D version established a tight ER-lysosomal network with the presence of extended patches of ER-lysosomal membrane-contact sites condition that reveals an increase of cell survival under stress conditions. Altogether, we propose stabilized HERPUD1 downregulates macroautophagy favoring instead a closed interplay between the ER and lysosomes with consequences in drug-cell stress survival.

Exosomes as Promising Nanostructures in Diabetes Mellitus: From Insulin Sensitivity to Ameliorating Diabetic Complications

Diabetes mellitus (DM) is among the chronic metabolic disorders that its incidence rate has shown an increase in developed and wealthy countries due to lifestyle and obesity. The treatment of DM has always been of interest, and significant effort has been made in this field. Exosomes belong to extracellular vesicles with nanosized features (30-150 nm) that are involved in cell-to-cell communication and preserving homeostasis. The function of exosomes is different based on their cargo, and they may contain lipids, proteins, and nucleic acids. The present review focuses on the application of exosomes in the treatment of DM; both glucose and lipid levels are significantly affected by exosomes, and these nanostructures enhance lipid metabolism and decrease its deposition. Furthermore, exosomes promote glucose metabolism and affect the level of glycolytic enzymes and glucose transporters in DM. Type I DM results from the destruction of β cells in the pancreas, and exosomes can be employed to ameliorate apoptosis and endoplasmic reticulum (ER) stress in these cells. The exosomes have dual functions in mediating insulin resistance/sensitivity, and M1 macrophage-derived exosomes inhibit insulin secretion. The exosomes may contain miRNAs, and by transferring among cells, they can regulate various molecular pathways such as AMPK, PI3K/Akt, and β-catenin to affect DM progression. Noteworthy, exosomes are present in different body fluids such as blood circulation, and they can be employed as biomarkers for the diagnosis of diabetic patients. Future studies should focus on engineering exosomes derived from sources such as mesenchymal stem cells to treat DM as a novel strategy.

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.

Thymoquinone-Enriched Naringenin-Loaded Nanostructured Lipid Carrier for Brain Delivery via Nasal Route: In Vitro Prospect and In Vivo Therapeutic Efficacy for the Treatment of Depression

In the current research, a thymoquinone-enriched naringenin (NGN)-loaded nanostructured lipid carrier (NLC) was developed and delivered via the nasal route for depression. Thymoquinone (TQ) oil was used as the liquid lipid and provided synergistic effects. A TQ- and NGN-enriched NLC was developed via the ultrasonication technique and optimized using a central composite rotatable design (CCRD). The optimized NLC exhibited the following properties: droplet size, 84.17 to 86.71 nm; PDI, 0.258 to 0.271; zeta potential, −8.15 to −8.21 mV; and % EE, 87.58 to 88.21%. The in vitro drug release profile showed the supremacy of the TQ-NGN-NLC in comparison to the NGN suspension, with a cumulative drug release of 82.42 ± 1.88% from the NLC and 38.20 ± 0.82% from the drug suspension. Ex vivo permeation study displayed a 2.21-fold increase in nasal permeation of NGN from the NLC compared to the NGN suspension. DPPH study showed the better antioxidant potential of the TQ-NGN-NLC in comparison to NGN alone due to the synergistic effect of NGN and TQ oil. CLSM images revealed deeper permeation of the NGN-NLC (39.9 µm) through the nasal mucosa in comparison to the NGN suspension (20 µm). Pharmacodynamic studies, such as the forced swim test and the locomotor activity test, were assessed in the depressed rat model, which revealed the remarkable antidepressant effect of the TQ-NGN-NLC in comparison to the NGN suspension and the marketed formulation. The results signify the potential of the TQ-enriched NGN-NLC in enhancing brain delivery and the therapeutic effect of NGN for depression treatment.

The interplay between oxidative stress and autophagy: focus on the development of neurological diseases

Regarding the epidemiological studies, neurological dysfunctions caused by cerebral ischemia or neurodegenerative diseases (NDDs) have been considered a pointed matter. Mount-up shreds of evidence support that both autophagy and reactive oxygen species (ROS) are involved in the commencement and progression of neurological diseases. Remarkably, oxidative stress prompted by an increase of ROS threatens cerebral integrity and improves the severity of other pathogenic agents such as mitochondrial damage in neuronal disturbances. Autophagy is anticipated as a cellular defending mode to combat cytotoxic substances and damage. The recent document proposes that the interrelation of autophagy and ROS creates a crucial function in controlling neuronal homeostasis. This review aims to overview the cross-talk among autophagy and oxidative stress and its molecular mechanisms in various neurological diseases to prepare new perceptions into a new treatment for neurological disorders. Furthermore, natural/synthetic agents entailed in modulation/regulation of this ambitious cross-talk are described.

The Difference in Expression of Autophagy-Related Proteins in Lesional and Perilesional Skin in Adult Patients with Active and Stable Generalized Vitiligo-A Cross-Sectional Pilot Study

Background:

Autophagy plays an important role in maintaining intracellular homeostasis and is essential for cell survival and cell death. Dysfunction of autophagy has been described in many autoimmune diseases but data on vitiligo are scarce.

Aims:

The aim of this pilot study was to investigate the expression of autophagy-related proteins in patients with vitiligo.

Methods:

Western blotting was used to analyze the expression of microtubule-associated protein light chain 3 (LC3II/I), autophagy-related gene 5 (Agt5), mammalian target of rapamycin (mTOR) and p62 in lesional and perilesional vitiligo skin from seven patients with active generalized vitiligo and nine patients with stable generalized vitiligo compared to control skin from six healthy subjects.

Results:

Our data showed increased expression of the autophagy marker LC3II/I and decreased p62 protein expression in lesional skin of active and stable vitiligo compared to control skin (P < 0.01). No significant difference in the expression of LC3II/I and p62 was found in perilesional skin of active vitiligo patients (P > 0.05) compared to control skin. Expression of LC3II/I in stable vitiligo lesional skin was higher and p62 expression was lower compared to active vitiligo lesional skin (P < 0.01). Decreased p62 expression was shown in perilesional skin of stable vitiligo patients (P < 0.05). Agt5 protein in lesional and perilesional skin of both active and stable vitiligo patients were increased (P < 0.01 and P< 0.05) compared to control skin. The expression of mTOR protein in lesional and perilesional skin of active and stable vitiligo patients was significantly lower than in control skin (P < 0.01).

Conclusions:

The present study indicates increased autophagy in lesional skin in vitiligo patients. Stable vitiligo lesional skin showed increased autophagy compared to active vitiligo lesional skin. Missing activation of autophagy in active vitiligo perilesional skin suggests disturbed autophagy to be associated with vitiligo.

Targeting Cancer Stem Cells by Dietary Agents: An Important Therapeutic Strategy against Human Malignancies

As a multifactorial disease, treatment of cancer depends on understanding unique mechanisms involved in its progression. The cancer stem cells (CSCs) are responsible for tumor stemness and by enhancing colony formation, proliferation as well as metastasis, and these cells can also mediate resistance to therapy. Furthermore, the presence of CSCs leads to cancer recurrence and therefore their complete eradication can have immense therapeutic benefits. The present review focuses on targeting CSCs by natural products in cancer therapy. The growth and colony formation capacities of CSCs have been reported can be attenuated by the dietary agents. These compounds can induce apoptosis in CSCs and reduce tumor migration and invasion via EMT inhibition. A variety of molecular pathways including STAT3, Wnt/β-catenin, Sonic Hedgehog, Gli1 and NF-κB undergo down-regulation by dietary agents in suppressing CSC features. Upon exposure to natural agents, a significant decrease occurs in levels of CSC markers including CD44, CD133, ALDH1, Oct4 and Nanog to impair cancer stemness. Furthermore, CSC suppression by dietary agents can enhance sensitivity of tumors to chemotherapy and radiotherapy. In addition to in vitro studies, as well as experiments on the different preclinical models have shown capacity of natural products in suppressing cancer stemness. Furthermore, use of nanostructures for improving therapeutic impact of dietary agents is recommended to rapidly translate preclinical findings for clinical use.

Study of the Possible Alleviated Role of Atorvastatin on Irinotecan-Induced Lingual Mucosal Damage: Histological and Molecular Study

BACKGROUND

Oral mucositis is the most debilitating and troublesome adverse effect of irinotecan (CPT-11) treatment. It adversely affects the patient quality of life. The aim of this work was to study the histological, immunohistochemical, and molecular changes in the oral mucosa by CPT-11 and the possible alleviated role of atorvastatin.

METHODS

Rats were randomly divided into control, CPT-11-treated group, and CPT-11+ atorvastatin-treated group. At the end of the experiment, the anterior two-thirds of the tongue was dissected out and divided into two parts: one part for light microscopic examination and the second for molecular study.

RESULTS

CPT-11-treated group revealed loss of normal mucosal organization, areas of ulceration and inflammation, and loss of architecture of lingual papillae. A significant decrease in immunohistochemical and molecular gene expression of Ki-67 and antiapoptotic Bcl-2 levels was observed. A significant increase in NF-κB immunohistochemical and mRNA gene expression level and a nonsignificant increase in Nrf2 gene expression were detected. Coadministration of atorvastatin showed remarkable improvement in the histopathological picture with a significant increase in Ki-67 and Bcl-2, a significant decrease in NF-κB protein and gene expression, and a significant increase in Nrf2 gene expression.

CONCLUSION

Atorvastatin substantially attenuates CPT-11-induced oral mucositis through the initiation of the antiapoptotic gene, modulation of the inflammatory, and antioxidant gene expression.

Mitochondrial stress response in drug-induced liver injury

Drug-induced liver injury (DILI) caused by the ingestion of medications, herbs, chemicals or dietary supplements, is a clinically widespread health problem. The underlying mechanism of DILI is the formation of reactive metabolites, which trigger mitochondrial oxidative stress and the opening of mitochondrial permeability transition (MPT) pores through direct toxicity or immune response, leading to cell inflammation, apoptosis, and necrosis. Traditionally, mitochondria play an indispensable role in maintaining the physiological and biochemical functions of cells by producing ATP and mediating intracellular signal transduction; drugs can typically stimulate the mitochondria and, in the case of sustained stress, can eventually cause impairment of mitochondrial function and metabolic activity. Meanwhile, the mitochondrial stress response, as an adaptive protective mechanism, occurs when mitochondrial homeostasis is threatened. In this review, we summarize the relevant frontier researches of the protective effects of mitochondrial stress response in DILI as well as the potential related mechanisms, thus providing some thoughts for the clinical treatment of DILI.

Silica dust exposure induces pulmonary fibrosis through autophagy signaling

Silicosis is a well-acknowledged occupational lung disease caused by inhalation of a large amount of free silica dust during the production period and eventually a considerable negative impact on the patients' quality of life. Autophagy exerts a critical influence on immune and inflammatory responses during the pathogenesis of pulmonary fibrosis. In this study, we sought to determine whether autophagy is involved in silicosis's pathogenesis and how it may affect pulmonary cellular physiology. In the animal experiments, we found persistent activation of autophagy in the development of pulmonary fibrosis, which was also accompanied by tumor necrosis factor and transforming growth factor expression increased. Therefore, the autophagy signaling pathway may regulate the inflammatory response and affect the progression of fibrosis. Further, in vitro experiments, we used LY294002, RAPA, and N-acetylcysteine (NAC) intervened autophagy. Our results showed that PI3K/Akt/mTOR signaling pathway is involved in the autophagy changed mediated by SiO₂ exposed, and autophagy might play a protective role in the progression of pulmonary fibrosis. Additionally, NAC's effect is not apparent on SiO₂ -mediated autophagy through the PI3K/Akt/mTOR signaling pathway, but it can reduce the inflammatory response on NR8383 cells mediated by SiO2-exposed. Nevertheless, it's interesting that NAC can reduce the inflammatory response on NR8383 cells mediated by SiO₂ -exposed. Taken together, our data demonstrated that SiO₂ -exposed can induce pulmonary fibrosis along with autophagy both in vivo and in vitro, NAC could alleviate the inflammatory response NR8383 cells by SiO₂ -exposed through non PI3K/Akt/mTOR signaling pathway, and the specific mechanism of its action needs further studying.

Beyond Self-Recycling: Cell-Specific Role of Autophagy in Atherosclerosis

Atherosclerosis is a chronic inflammatory disease of the arterial vessel wall and underlies the development of cardiovascular diseases, such as myocardial infarction and ischemic stroke. As such, atherosclerosis stands as the leading cause of death and disability worldwide and intensive scientific efforts are made to investigate its complex pathophysiology, which involves the deregulation of crucial intracellular pathways and intricate interactions between diverse cell types. A growing body of evidence, including in vitro and in vivo studies involving cell-specific deletion of autophagy-related genes (ATGs), has unveiled the mechanistic relevance of cell-specific (endothelial, smooth-muscle, and myeloid cells) defective autophagy in the processes of atherogenesis. In this review, we underscore the recent insights on autophagy's cell-type-dependent role in atherosclerosis development and progression, featuring the relevance of canonical catabolic functions and emerging noncanonical mechanisms, and highlighting the potential therapeutic implications for prevention and treatment of atherosclerosis and its complications.

Recent advances in the field of caloric restriction mimetics and anti-aging molecules

Caloric restriction (CR) mimetics are molecules that produce beneficial effects on health and longevity in model organisms and humans, without the challenges of maintaining a CR diet. Conventional CR mimetics such as metformin, rapamycin and spermidine activate autophagy, leading to recycling of cellular components and improvement of physiological function. We review here novel CR mimetics and anti-aging compounds, such as 4,4'-dimethoxychalcone, fungal polysaccharides, inorganic nitrate, and trientine, highlighting their possible molecular targets and mechanisms of action. The activity of these compounds can be understood within the context of hormesis, a biphasic dose response that involves beneficial effects at low or moderate doses and toxic effects at high doses. The concept of hormesis has widespread implications for the identification of CR mimetics in experimental assays, testing in clinical trials, and use in healthy humans. We also discuss the promises and limitations of CR mimetics and anti-aging molecules for delaying aging and treating chronic diseases.

Towards precision nanomedicine for cerebrovascular diseases with emphasis on Cerebral Cavernous Malformation (CCM)

Introduction: Cerebrovascular diseases encompass various disorders of the brain vasculature, such as ischemic/hemorrhagic strokes, aneurysms, and vascular malformations, also affecting the central nervous system leading to a large variety of transient or permanent neurological disorders. They represent major causes of mortality and long-term disability worldwide, and some of them can be inherited, including Cerebral Cavernous Malformation (CCM), an autosomal dominant cerebrovascular disease linked to mutations in CCM1/KRIT1, CCM2, or CCM3/PDCD10 genes.Areas covered: Besides marked clinical and etiological heterogeneity, some commonalities are emerging among distinct cerebrovascular diseases, including key pathogenetic roles of oxidative stress and inflammation, which are increasingly recognized as major disease hallmarks and therapeutic targets. This review provides a comprehensive overview of the different clinical features and common pathogenetic determinants of cerebrovascular diseases, highlighting major challenges, including the pressing need for new diagnostic and therapeutic strategies, and focusing on emerging innovative features and promising benefits of nanomedicine strategies for early detection and targeted treatment of such diseases.Expert opinion: Specifically, we describe and discuss the multiple physico-chemical features and unique biological advantages of nanosystems, including nanodiagnostics, nanotherapeutics, and nanotheranostics, that may help improving diagnosis and treatment of cerebrovascular diseases and neurological comorbidities, with an emphasis on CCM disease.

Anti-tumor activity of resveratrol against gastric cancer: a review of recent advances with an emphasis on molecular pathways

Gastric cancer (GC) is one of the most common cancers with high malignancy. In spite of the great development in diagnostic tools and application of anti-tumor drugs, we have not witnessed a significant increase in the survival time of patients with GC. Multiple studies have revealed that Wnt, Nrf2, MAPK, and PI3K/Akt signaling pathways are involved in GC invasion. Besides, long non-coding RNAs and microRNAs function as upstream mediators in GC malignancy. GC cells have acquired resistance to currently applied anti-tumor drugs. Besides, combination therapy is associated with higher anti-tumor activity. Resveratrol (Res) is a non-flavonoid polyphenol with high anti-tumor activity used in treatment of various cancers. A number of studies have demonstrated the potential of Res in regulation of molecular pathways involved in cancer malignancy. At the present review, we show that Res targets a variety of signaling pathways to induce apoptotic cell death and simultaneously, to inhibit the migration and metastasis of GC cells.

Role of autophagy in regulating interleukin-10 and the responses to corticosteroids and statins in asthma

BACKGROUND

Interleukin (IL)-10 is a key anti-inflammatory cytokine that may be reduced in asthma but is enhanced by corticosteroids, especially when combined with a statin, although the mechanisms of these effects are uncertain.

OBJECTIVE

To study the role of autophagy in macrophages in promoting inflammation in asthma through reducing IL-10 secretion and how corticosteroids and statins may reverse this process.

METHODS

We conducted a randomised double-blind placebo-controlled study in moderate to severe asthmatic patients (n = 44) to investigate the effect of an inhaled corticosteroid (budesonide 400 μg/day) and the combination of budesonide with an oral statin (simvastatin 10 mg/day) given for 8 weeks on autophagy protein expression in sputum cells by using immunocytochemistry and measurement of IL-10 release. In in vitro experiments, we studied cross-regulation between autophagy and IL-10 release by measuring the expression of autophagy proteins in M2-like macrophages and the effects of budesonide and simvastatin on these mechanisms.

RESULTS

In asthmatic patients, inhaled budesonide inhibited airway macrophage autophagy (beclin-1, LC3) as well as autophagic flux (p62), which was enhanced by simvastatin and was correlated with increased sputum IL-10 and reduced IL-4 concentrations. In macrophages in vitro, budesonide and simvastatin inhibited rapamycin-induced autophagy as well as autophagic flux, with reduced expression of beclin-1 and LC3, but enhanced the accumulation of p62 and increased expression of IL-10, which itself further inhibited autophagy in macrophages. With siRNA-mediated silencing, LC3-deficient macrophages also showed a maximal induction of IL-10 transcription. Neutralisation of IL-10 with recombinant specific blocking antibody and silencing IL-10 transcription reversed the inhibitory effects of budesonide and simvastatin on macrophage autophagy.

CONCLUSION AND CLINICAL RELEVANCE

Inhibition by corticosteroids and a statin of macrophage autophagy enhances IL-10 production, resulting in the control of asthmatic inflammation.

Statins: Could an old friend help in the fight against COVID-19?

The COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has overwhelmed healthcare systems requiring the rapid development of treatments, at least, to reduce COVID-19 severity. Drug repurposing offers a fast track. Here, we discuss the potential beneficial effects of statins in COVID-19 patients based on evidence that they may target virus receptors, replication, degradation, and downstream responses in infected cells, addressing both basic research and epidemiological information. Briefly, statins could modulate virus entry, acting on the SARS-CoV-2 receptors, ACE2 and CD147, and/or lipid rafts engagement. Statins, by inducing autophagy activation, could regulate virus replication or degradation, exerting protective effects. The well-known anti-inflammatory properties of statins, by blocking several molecular mechanisms, including NF-κB and NLRP3 inflammasomes, could limit the "cytokine storm" in severe COVID-19 patients which is linked to fatal outcome. Finally, statin moderation of coagulation response activation may also contribute to improving COVID-19 outcomes. LINKED ARTICLES: This article is part of a themed issue on The Pharmacology of COVID-19. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.21/issuetoc.

Ligustilide alleviates neurotoxicity in SH-SY5Y cells induced by Aβ25-35 via regulating endoplasmic reticulum stress and autophagy

Ligustilide is a phenolic compound isolated from Asian plants of Umbelliferae family. This study was aimed at exploring the neuroprotective effects of Ligustilide from the perspective of endoplasmic reticulum stress (ERS) and autophagy. The Alzheimer's disease (AD) cell models were constructed by SH-SY5Y cell line, which was exposed to 20 μM Aβ_25-35 . CCK-8 was used to evaluate the cell viability of Ligustilide on AD cell model. Hoechst staining and LysoTracker Red were used to test the cell apoptosis and Lysosome function, respectively. ERS in living cells were detected by Thioflavin T. The expression of autophagy-related proteins (LC3B-II/I, P62/SQSTM1, Beclin1, and Atg5), ERS marker proteins (PERK, GRP78, and CHOH), and apoptosis proteins (Bax, Bcl-2, and Caspase-12) were analyzed by Western blot analyses. Aβ_25-35 could induce ERS and autophagy in a time-dependent manner in SH-SY5Y cells. We demonstrated that Ligustilide significantly decreased the rate of apoptosis, and improved the viability of cells. Simultaneously, Ligustilide effectively modulated ERS via inhibiting the over-activation of GRP78/PERK/CHOP signaling pathway. In addition, Ligustilide alleviated the accumulation of autophagy vacuoles, reduced the ratio of LC3B-II/I and the level of P62/SQSTM1. Ligustilide significantly up-regulated lysosomal acidity and the expression of Cathepsin D (CTSD). Ligustilide could rescue lysosomal function to promote autophagy flux and inhibit the over-activation of ERS. This finding may contribute to the development of new therapeutic strategies for AD.

Back to Nucleus: Combating with Cadmium Toxicity Using Nrf2 Signaling Pathway as a Promising Therapeutic Target

There are concerns about the spread of heavy metals in the environment, and human activities are one of the most important factors in their spread. These agents have the high half-life resulting in their persistence in the environment. So, prevention of their spread is the first step. However, heavy metals are an inevitable part of modern and industrial life and they are applied in different fields. Cadmium is one of the heavy metals which has high carcinogenesis ability. Industrial waste, vehicle emissions, paints, and fertilizers are ways of exposing human to cadmium. This potentially toxic agent harmfully affects the various organs and systems of body such as the liver, kidney, brain, and cardiovascular system. Oxidative stress is one of the most important pathways of cadmium toxicity. So, improving the antioxidant defense system can be considered as a potential target. On the other hand, the Nrf2 signaling pathway involves improving the antioxidant capacity by promoting the activity of antioxidant enzymes such as catalase and superoxide dismutase. At the present review, we demonstrate how Nrf2 signaling pathway can be modulated to diminish the cadmium toxicity.